JP3247412B2 - Ink jet recording method, ink jet recording apparatus, and ink jet recording head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording head for recording by discharging ink using thermal energy, an ink jet recording method using the head, and an ink jet recording apparatus.

[0002]

2. Description of the Related Art Conventionally, in an ink jet recording apparatus or the like, in order to minimize the occurrence of density fluctuation and density unevenness in a recorded image or the like, in particular, the ejection direction (landing accuracy) and the ejection amount (hereinafter, referred to as ejection amount) of a recording head. This amount is referred to as Vd [p
1 / dot]).

[0003] The main technique employed in these controls is to adjust the temperature of the ink (hereinafter referred to as temperature control).
Some control the viscosity of the ink, which affects the ejection amount. In a method in which bubbles are generated in ink by thermal energy and the ink is discharged by the growth of the bubbles, there is a method in which the conditions for generating bubbles are controlled to stabilize the discharge amount. As a specific configuration for adjusting the ink temperature, a heater for heating the recording head holding the ink (also serving as a dedicated heater or a discharging heater), a temperature sensor for detecting the temperature related to the recording head, Is used to feed back the temperature detected by the temperature sensor to the amount of heating by the heater. There is also a configuration in which heating by a heater is simply adjusted without feedback of temperature.

In the above-described configuration, the heater and the temperature sensor may be provided in the vicinity of the print head, for example, on a member constituting the print head, or may be provided outside the print head.

As another method for controlling the discharge amount or the like, or as a method used together with the above method, an electrothermal converter (hereinafter also referred to as a discharge heater) for generating thermal energy in the above-described discharge method generates heat energy. Pulse (hereinafter, referred to as heat pulse)
In some cases, the amount of generated heat is controlled to stabilize the discharge amount by changing the pulse width of the pulse.

The following four modes are mainly used as the control modes described above.
Are distinguished into two aspects.

1) Always perform head temperature control (external / nearby).

[0008] With temperature feedback.

2) The head temperature is adjusted as needed (external / nearby).

[0010] With temperature feedback.

3) Perform high-temperature head temperature control (higher than ambient temperature). With feedback.

4) Pulse width modulation of a single heat pulse.

[0013]

SUMMARY OF THE INVENTION However, the above 1)
In the above method, the temperature of the print head is always adjusted,
The evaporation of the ink moisture accompanying the heating of the heater is promoted, so that the viscosity of the ink in the ejection openings in the recording head increases,
As a result of inducing sticking and increasing the amount of deflection or non-ejection that deflects in the ejection direction, or causing a change in density or uneven density due to the relative increase in the dye density of the ink, the recording image quality is reduced. I was invited. In addition, as a result of the continuous heating by the heater, a change in the structure of the head and the deterioration of members constituting the head are promoted, and the reliability and durability of the recording head are reduced. In addition, this method is generally susceptible to changes in environmental temperature and self-heating (heating by printing), which may cause fluctuations in the ejection amount, causing density changes and density unevenness.

The second method is a method for adjusting the temperature as required, and is an improvement of the first method. For example, since the temperature is adjusted after a print command is input, the method can be performed in a relatively short time. , It is necessary to reach a predetermined temperature, and a large amount of energy [for example, the calorific value (W) of the heater] must be given for heating. For this reason, in the temperature control, the width of the temperature ripple may increase and accurate temperature control may not be performed. In such a case, the discharge amount may fluctuate due to the temperature ripple, and density change or density unevenness may occur.
Conversely, if an accurate temperature control is to be performed, it is necessary to reduce the applied energy, the time required to reach the target temperature is increased, and the waiting time until the start of printing is increased.

In the third method, the temperature control temperature is set higher than the environmental temperature in order to reduce the influence of a change in the environmental temperature or a temperature change due to a self-heating (heating by printing).
This makes it possible to reduce the variation in the discharge amount during low-duty printing, but when high-duty printing, for example, when the temperature rise due to printing is large, such as in all solid printing, the effect of this temperature rise is reduced. It cannot be avoided.

As a method of controlling the temperature, the temperature control outside the recording head can generally reduce the influence of the environmental temperature, but has a poor response to the self-heating, and is affected by the self-heating. It can be said that it is easy.

If the temperature is controlled in the vicinity of the recording head (for example, a heater or a temperature sensor is provided on an aluminum plate as a substrate supporting a heater board on which a discharge heater is provided), the response is improved, and printing is performed. Although effective for raising the temperature, a temperature ripple may occur due to a large heat capacity of the aluminum plate serving as the substrate, and the discharge amount may fluctuate due to the temperature ripple.

Further, a single pulse of the above method 4 (hereinafter referred to as a single pulse)
The pulse width modulation method (also called single pulse)
In particular, in the above-described bubble-forming ink-jet method, when the control range of the discharge amount is small enough to absorb the change in the discharge amount corresponding to the temperature change, and when it is difficult to obtain a linear increase in the discharge amount with an increase in the pulse width. The present inventors have recognized that it is necessary to improve the reproducibility and perform more accurate ejection amount control in order to achieve high image quality.

Further, in addition to the above-mentioned problem of the discharge amount fluctuation,
The adverse effects caused by the self-heating of the recording head also cause changes in the discharge characteristics during printing due to changes in the ink temperature and changes in the control characteristics due to changes in the head structure, causing deflection, non-discharge, and a drop in the refill frequency. The image may be extremely deteriorated.

In the case of replaceable ink jet cartridges, since these are mass-produced, the area of a heater board (HB) on a silicon chip formed in a semiconductor manufacturing process for manufacturing a head and the like are not considered. Variations in the manufacturing process occur in the resistance value, the film structure, the diameter of each discharge port, and the like. For this reason, there may be variations in the discharge amount for each discharge port in one head, and variations in the performance for each head.

Further, the variation in the head discharge characteristics causes a change in the control characteristics during printing as well as the initial discharge amount. Among the head ejection characteristics, a variation in the ejection amount and the control characteristics of each head has a particularly great effect on image formation.

The above problem directly affects the image quality of a printed matter. In particular, for example, in the case of full-color recording formed by using four inks of cyan, magenta, yellow, and black, a recording head corresponding to each of these is used. If at least one ejection characteristic different from the standard state appears, this change in the ejection characteristic causes a difference in the ejection amount. As a result, a change in color tone and a decrease in color reproducibility (an increase in color difference) due to the collapse of the color balance are caused, and the image quality is reduced. Further, when a monochromatic image such as black, red, blue, or green is recorded, streaking and density fluctuation in solid printing become remarkable due to non-ejection. Further, there is a problem that the reproducibility of fine lines and the quality of characters are deteriorated due to the occurrence of deviation.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a discharge amount irrespective of a change in environmental temperature or a change in temperature caused by temperature rise (self-temperature rise) by printing. Is to stabilize.

Another object of the present invention is to provide an ink jet recording method and an ink jet recording apparatus which can reduce the influence of self-heating.

Further, another object of the present invention is to correct an initial discharge amount variation caused by a head manufacturing process, particularly in an ink jet recording apparatus using a detachably mounted ink jet recording head.
The purpose is to control the discharge amount appropriately. Further, as another object, an ink jet recording head capable of reducing the head cost by enabling the use of a head which has been difficult to use due to an excessive or insufficient ejection amount in the past and improving the yield of the head. And an ink jet recording apparatus and an ink jet recording method.

Still another object of the present invention is to provide an ink jet recording apparatus capable of stably changing the ejection amount over a wide range and further applicable to gradation recording.

[0027]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(Embodiment 1) FIG. 1 is a diagram for explaining a divided pulse according to an embodiment of the present invention.

In FIG. 1, V _OP is a drive voltage, P ₁ is a pulse width of a first pulse (hereinafter, referred to as a pre-heat pulse) of a plurality of divided heat pulses, P ₂ is an interval time, and P ₃ is a second pulse. It is a pulse width of a pulse (hereinafter, referred to as a main heat pulse). T ₁ , T ₂ , and T ₃ indicate times for determining P ₁ , P ₂ , and P ₃ . The drive voltage V _OP provides electric energy necessary for the electric heat converter to which the voltage is applied to generate heat energy in the ink in the ink liquid path formed by the heater board and the top plate. The value is determined by the area and resistance of the electrothermal transducer, the film structure, and the liquid path structure of the recording head. In the divided pulse width modulation driving method, a pulse is sequentially applied with a width of P ₁ , P ₂ , and P ₃ . The preheat pulse is a pulse for mainly controlling the temperature of the ink in the liquid path, and plays an important role in the ejection amount control of the present invention. The preheat pulse width is set to a value such that the foaming phenomenon does not occur in the ink due to the thermal energy generated by the electrothermal transducer when the preheat pulse width is applied.

The interval time is provided to provide a predetermined time interval so that the preheat pulse and the main heat pulse do not interfere with each other, and to make the temperature distribution of the ink in the ink liquid passage uniform. The main heat pulse is caused to foam in the ink in the liquid passage is for discharging ink from the discharge port, the area of the width P ₃ is an electrothermal transducer, resistance, film structure and the recording head It is determined by the structure of the ink liquid path.

For example, the operation of the preheat pulse in the recording head having the structure shown in FIGS. 2A and 2B will be described.

FIGS. 2A and 2B are a schematic longitudinal sectional view and a schematic front view, respectively, showing an example of the configuration of a recording head to which the present invention can be applied, along the ink liquid path.

2 (A) and 2 (B), reference numeral 1 denotes an electrothermal converter (discharge heater) which generates heat by applying the divided pulse, and the electrothermal converter 1 applies the divided pulse thereto. On the heater board 9 together with the electrode wiring and the like. The heater board 9 is formed of silicon Si, and is supported by an aluminum plate 11 forming a substrate of a recording head. Reference numeral 12 denotes a top plate on which a groove for forming an ink liquid path and the like is formed. The top plate 12 and the heater board 9 (the aluminum plate 11) are joined to supply the ink liquid path 3 and ink thereto. A common liquid chamber 5 is formed.
In addition, discharge ports 7 are formed in the top plate 12, and each of the discharge ports 7 communicates with the ink liquid path 3.

In the recording head shown in FIG. 2, the driving voltage V _OP = 18.0 (V) and the main heat pulse width P
₃ = 4.114 and [.mu.sec], when changing the preheat pulse width P ₁ in the range of 0~3.000 [μsec], the discharge amount as shown in FIG. 3 V _d [ng / dot] and the pre-heat pulse The relationship with the width P ₁ [μsec] is obtained.

FIG. 3 is a diagram showing the dependency of the ejection amount on the preheat pulse. In the figure, V ₀ is P ₁ = 0 [μsec
c], and this value is determined by the head structure shown in FIG. Incidentally, V ₀ in the present embodiment is V ₀ = 18.0 [ng / dot] when the environmental temperature T _R = 25 ° C.
Met.

[0036] As shown in curve a of Figure 3, in accordance with an increase in the pulse width P ₁ of the pre-heat pulse, the ejection amount V _d is the pulse width P ₁ is increased with a linearity from 0 to P _1LMT In the range where the pulse width P ₁ is larger than P _1LMT , the change loses linearity and saturates and becomes maximum at the pulse width P _1MAX .

[0037] Thus, the range of variation of the ejection amount V _d relative to the change in the pulse width P ₁ until the pulse width P _1LMT showing the linearity is easily control the discharge amount by changing the pulse width P ₁ It is effective as a range that can be performed. _Incidentally , in this embodiment shown by the curve a, P _1LMT = 1.87 (μs), and the discharge amount at this time is V _LMT = 24.0 [ng / do].
t]. The pulse width P _1MAX when the discharge amount V _d is saturated is P _1MAX = 2.1 [μs],
The discharge amount V _{MAX at} this time was 25.5 [ng / dot].

[0038] When the pulse width is greater than P _1MAX, the ejection amount V _d is smaller than V _MAX. This phenomenon is that when a preheat pulse having a pulse width in the above range is applied, fine bubbling (a state immediately before film boiling) occurs on the electrothermal transducer, and the next main heat pulse is generated before the bubble disappears. The ejection rate is reduced by the applied micro bubbles, which disturb the bubbling by the main heat pulse. This region is called a pre-foaming region, and in this region, it becomes difficult to control the discharge amount via a preheat pulse.

In FIG. 3, P ₁ = 0 to P _1LMT [μs]
If the slope of the straight line indicating the relationship between the discharge amount and the pulse width in the range of is defined as the preheat pulse dependence coefficient, the preheat pulse dependence coefficient is:

[0040]

(Equation 1)

## EQU1 ## This coefficient K _P is determined by the head structure, driving conditions, physical properties of the ink, and the like irrespective of the temperature. That is, curves b and c in FIG. 3 show the case of another print head, and it can be seen that the discharge characteristics change when the print head is different. As described above, since the upper limit value _P1LMT of the preheat pulse P1 is different when the printheads are different, the discharge amount control is performed by setting the upper limit value _P1LMT for each printhead as described later. In the print head and the ink indicated by the curve a in the present embodiment, K _P = 3.209 [ng / μs]
ec · dot].

Another factor that determines the ejection amount of the ink jet recording head is the recording head temperature (ink temperature).
There is.

FIG. 4 is a diagram showing the temperature dependence of the discharge amount. As shown in curve a of FIG. 4, the ejection amount V _d relative to the increase in environmental temperature T _R of the recording head (= head temperature T _H) increases linearly. If the slope of this line is defined as a temperature-dependent coefficient, the temperature-dependent coefficient:

[0044]

(Equation 2)

Is as follows. This coefficient K _T does not depend on the driving conditions, but is determined by the structure of the head, the physical properties of the ink, and the like. FIG.
Also, curves b and c show the cases of other recording heads.
In the recording head of this embodiment, K _T = 0.3 [ng / ng].
° C · dot].

As described above, the discharge amount control according to the present invention can be performed by using the relationships shown in FIGS.

Here, the principle of the discharge amount control method using double pulses according to the present invention will be described in detail.

FIG. 5 shows the relationship between the ink temperature: T (° C.) and the ink viscosity: η (T) (cp). From this graph, it can be seen that the ink viscosity decreases as the ink temperature increases. Therefore, if the ink temperature has a relationship of Ta <Tb, ηa> ηb.

[0049] FIG. 6 (A) and (B) is a constant energy required for foaming shows a foamed state when given by the main pulse P _3, especially if the ink temperature is different, that is, the ink The state of the foam growth boundary region when the viscosity is different is shown.

The ink shown in Fig (A) Temperature: ink against p _0, when you Osaeyo it: if Ta is low, the ink viscosity: .eta.a high, therefore, the pressure of air bubbles is to grow Element due to the viscosity of the material: Ra (η)
Since the portion is large, the foam growth area can reach only up to the one-dot chain line.

On the other hand, the ink temperature: Tb shown in FIG.
When the pressure is high, the ink viscosity: ηb is low, and therefore, the pressure _element for growing bubbles: p ₀ , and the resistance element due to the viscosity of the ink for suppressing the pressure: Rb
Since the (η) portion becomes smaller, the foam growth region can reach the two-dot chain line.

In the actual head, since the impedance is changed for each direction of the liquid path in order to stabilize the discharge characteristics and the refill, the actual foaming is not symmetric with respect to the heater.

As described above, in order to increase the foaming growth area, that is, the foaming volume in order to increase the amount of ejected ink, not only the ink temperature near the heater but also the ink temperature around the heater are increased. Therefore, the present invention has been made in view of such a point.

[0054] in FIG. 7 (A), cross-sectional view near the discharge ports of the ink jet head using heat energy, FIG. (B) to preheat pulse: how the time variation of the temperature distribution of the ink from giving P ₁ Indicated. FIG. 4C shows the relationship between the heat pulses P ₁ and P ₃ .

First, at the time t ₁ (μsec) immediately after the application of the pulse energy of P ₁ , the ink temperature near the heater (a, b, b ′) as shown by the solid line in FIG. Is high, but a little away from the heater (c,
The ink temperature in c ') is rapidly decreasing.

Next, at time t ₂ (μsec) about 1 microsecond has elapsed since the application of the pulse P ₁ , as shown by a dashed line in FIG.
b, b 'ink temperature) is spaced slightly although reduced (c, c') Inkuondo has risen compared to t ₁ in further distant (d, ink temperature d ') also It rises slightly.

[0057] Then, the elapsed before and after a few microseconds from giving P ₁ main heat pulse: t ₃ just before giving the P ₃
At (μsec), the ink temperature near the heater (a, b, b ′) further decreases as indicated by the two-dot chain line in FIG. The ink temperature further rises, and even the farther (d, d ') ink temperature approaches the ink temperature almost at the position near the heater.

As described above, in order to raise the temperature of the ink considerably far from the heater position, it is understood that a certain time (interval time P ₂ ) is required after applying a certain pulse energy.

Here, in the process in which the applied energy is thermally conducted with time and the ink temperature distribution changes, the total amount of energy in the adiabatic system is constant.

[0060] be applied to t ₂ at the main heat pulse P _3, a heater near (a, b, b ') the ink temperature heater periphery of high (c, c' of the ink temperature in) rises sufficiently Therefore, the bubble growth area is smaller than when the pulse P ₃ is applied at t ₃ , and thus the ink ejection amount is not large. Alternatively, even if the preheat pulse P ₁ is given,
When preheat pulse secured only interval time P ₂ required to sufficiently diffuse the energy of the P ₁ (long) and unless, since the ink temperature of the heater around which contribute to the growth of the foam does not rise, it bubbles foamed It does not grow significantly, and a desired ink discharge amount cannot be obtained.

That is, the interval time P ₂ has a function of conducting the energy of the preheat pulse P ₁ to the foam growth boundary area around the heater, in other words, a function of forming a desired ink temperature distribution around the heater. and is, this length similar to the pre-heat pulse P _1, is an important parameter for the ejection amount control.

As described above, according to the ejection amount control principle of the present invention, variable energy for raising the ink temperature is given by the variable preheat pulse P ₁ , and this energy is supplied to the bubble growth boundary region by the interval time P ₂ . by conduction, after forming a desired ink temperature distribution and to obtain a desired ink discharge amount by the main heat pulse P _3.

[0063] That is, a preheat pulse P ₁ of the double pulse, both by the interval time P ₂ until the main heat pulse P _3, by using both the course input energy and time, the foam growth boundary region of the heater around The distribution of the ink temperature T (x, y, z), that is, the ink viscosity distribution η (x, y, z) depending on the ink temperature is formed to control the foaming area, thereby enabling the discharge amount to be controlled.

[0064] Incidentally, as shown in FIG. 9, the above description and below, to convert the input energy of the pre-heat pulse P ₁ efficiently discharge energy, when the maximum neighboring ink discharge amount, i.e., the pre-heat pulse P ₁
In the case of the width of the longest even the length of the interval time P ₂ is required not shorter than the width of the preheat pulse P _1. Preheat pulse P input energy is increased by _one in the width by the longest, the ink temperature of the heater near the highest, the foam growth region Failure to sufficiently long interval time P ₂ is because not a maximum It is.

By increasing the temperature of the ink in the vicinity of and around the heater, the foam growth rate is increased, and the amount of ink to be vaporized is also increased. Contribute to the increase.

FIG. 8 is a diagram for explaining the discharge amount control according to an embodiment of the present invention. The control principle of the discharge amount will be described with reference to FIG.

As shown in FIG. 8, the discharge amount control is constituted by the following three modes. That is, according to the temperature T _H of the recording _{head, (1) T H ≦ T} 0 ... discharge amount control by the temperature control _{(2) T 0 <T H} ≦ T L ... discharge amount control by the divided pulse width modulation method (3 ) T _L uncontrolled where by _{<T H <T C ... P} 1 = 0, T H is T _C or more is an area that exceeds the foam limit of the ink jet recording head.

[0068] Thus, in the following head temperature T _H is relatively low T ₀ (for example 25 ° C.) performs the ejection amount by temperature control of the recording head described above, at T ₀ or more relatively high temperature, FIG. The discharge amount is controlled by changing the pulse width of the preheat pulse described in 3 (hereinafter, also referred to as PWM control).

As described above, the manner of controlling the ejection amount in accordance with the head temperature is such that in a relatively low temperature region, foaming when heat is applied to ink is unstable due to an increase in ink viscosity. In some cases, the ejection itself may not be performed properly, and therefore, it is difficult to control the ejection amount by pulse width modulation. Therefore, when the head temperature is low, the head temperature is previously set to a predetermined temperature (T ₀ ) by temperature control, whereby the ejection amount is controlled to a constant amount,
When the head temperature is high, the ejection amount is controlled by modulating the preheat pulse at the time of ejection.

The above-mentioned temperature T ₀ is the print head temperature targeted by the temperature control. When the print head is at this temperature, the target discharge amount V
_d0 (for example, 30 [ng / dot]) is obtained. The temperature T _{L at} which the discharge amount control shown in FIG.
Can be set as the temperature corresponding to the control limit discharge amount V _LMT shown in FIG. 3 in the relationship between the temperature and the discharge amount shown in FIG.

The mode (1) corresponds to the temperature control area shown in FIG. 8, and as described above, is mainly for securing a predetermined amount of discharge in a low-temperature environment. Is controlled to the target temperature T ₀ by temperature control. As a result, the ejection amount V _d0 when the print head temperature T _H = T ₀ is obtained.

In this embodiment, T ₀ is set to 25 ° C. in order to minimize the above-mentioned adverse effects due to temperature control (thickening, sticking, and temperature control ripples due to evaporation of ink water). This is because, for example, the room temperature is about 20
This is because the recording head temperature is maintained at about 25 ° C., and if the recording head temperature is kept substantially at this temperature, the above-mentioned adverse effects can be reduced. Also, the pulse width P ₁ of the preheat pulse at this time is
Is set to P ₁ = P _{1LMT so} that the maximum discharge amount V _LMT can be obtained at T _H = 25 ° C. Further, in the control mode of (1), that is, each pulse width and the like at the time of temperature control are P ₁ = 1.87 (μsec), as shown in FIG.
P ₂ = 2.618 (μsec), P ₃ = 4.114 (μ
sec). This state corresponds to 1 in a table shown in FIG. 10 described later.

The control mode (2) corresponds to the pulse width modulation area shown in FIG. This region is a region (for example, 26 ° C. to 44 ° C.) where the recording head temperature is relatively high at T ₀ or more due to self-heating by printing or a high environmental temperature, and this temperature is detected by a temperature sensor. changing the preheat pulse width P ₁ according to the table shown in FIG. FIG. 9 shows each state of the pulse width corresponding to each of the table numbers in FIG. FIG. 11 shows a pulse width modulation sequence at this time. In the case of the _print head of this example, the upper limit P _1LMT of the width of the pulse P ₁ is OA [Hex] indicated by the table number 1 in FIG. 10, that is, the value indicated by 1 in FIG. This upper limit is set by table pointer information as described later.

Hereinafter, the discharge amount control based on the pulse width modulation shown in FIG. 8 will be described with reference to the sequence of FIG.

The sequence shown in FIG.
The printhead temperature is started by interruption every second. First, in step S401, the printhead temperature is detected. Next, in step S402, in order to prevent erroneous temperature detection due to heat flux entering the temperature sensor and electrical noise,
Times of the average value of the head temperature and the head temperature detected in step S401 performs processing for the T _m. Next step S4
In 03 compares the average value T _m-1 of the head temperature and the average value was obtained T _m and the last. Here, the difference T _m −T _m−1 is a predetermined temperature step width ΔT, that is, a pulse width P ₁ ,
One unit pulse width (0.187 μsec) corresponding to the change width of the pulse width at each stage corresponding to the table number shown in FIG.
c) Within the temperature range in which the discharge rate is kept constant when changed (that is, ± ΔT is the temperature range ± 1 ° C. shown in FIG. 10).
(Corresponding to (2 ° C.)), step S405
In the pulse width P ₁ is kept unchanged, the difference process proceeds to step S406 if there is greater than + [Delta] T, by increasing one reference table number of the table of FIG. 10, P
₁ was reduced one lowered discharge amount, and if the difference is less than -ΔT proceeds to step S404, increases the discharge amount of the P ₁ one raised by lowering one table number, Control is performed such that the discharge amount always becomes a constant amount V _d0 . In the process, in order to prevent the occurrence of density jump reason for the change in the pulse width P ₁ for changing the one unit pulse width to prevent feedback malfunction (temperature sensors erroneous detection, etc.) depending on the temperature change is there. In this embodiment, the average value of the two left and right temperature sensors is used as the temperature of the recording head.

[0076] Although determines the pulse width P ₁ by comparing the head temperature T _m-1 of the previous and the head temperature T _m of a current in the step S403, or in other determination methods. For example, by comparing the current head temperature T _m belongs table number and the previous head temperature T _m-1 belongs table number, according to the difference of the table number, the step S404
It may determine the pulse width P ₁ in ~S406.

Further, the average value detected four times is used for temperature detection to prevent erroneous detection due to sensor noise or the like, smoothly perform feedback, minimize the density fluctuation by control, and use the serial printing method. This is to make the density change at the connection (connection streak) inconspicuous.

By performing the above-described control, the discharge amount can be controlled in the range of ± ΔV with respect to the target discharge amount V _{d0 in the} temperature range that can be managed by the table of FIG. The state of the change in the ejection amount changes, for example, as indicated by an arrow a in FIG.

If the variation in the discharge amount within this range falls within the range, the density variation occurring during printing of one sheet is suppressed to about ± 0.2 even in the case of 100% duty printing, which is remarkable in the serial printing method. The occurrence of density unevenness and connecting streaks does not matter. When the average number of temperature detections is increased, noise and the like are increased, resulting in a smoother change. On the other hand, in real-time control, detection accuracy is impaired and accurate control cannot be performed. In addition, when the average number of temperature detections is reduced, the temperature is weakened to noise and the like, and a rapid change occurs. On the other hand, in real-time control, the detection accuracy is increased and accurate control is possible.

The control mode (3) corresponds to the non-control area shown in FIG. 8, and this temperature range is outside the normal printing range of the recording head and is a range that is not often used. However, for example, when printing is performed at 100% duty, the temperature may rise to this temperature range. In such a case, P ₁ = 0 (μsec
As c), printing is performed only by a single main heat pulse to prevent self-heating as much as possible. T _C indicates the operating limit temperature of the head.

In this embodiment, the table shown in FIG.
By performing the sequence shown in FIG. 11, the ejection amount is controlled in a fluctuation range of ΔV = ± 0.3 [ng / dot] around V _d0 = 30 [ng / dot] until the head temperature T _H = 46 ° C. Became possible.

FIG. 12 shows a heater board of a recording head which can be used in the above embodiment. On the heater board, a temperature sensor, a temperature control heater, a discharge heater, and the like are arranged.

FIG. 12 is a schematic top view of a heater board. In the figure, temperature sensors 20A and 20B are Si
The plurality of discharge heaters 1 are arranged on the left and right sides of the array on the substrate 9. The discharge heater 1 and the temperature sensors 20A and 20B are arranged in a pattern together with the temperature control heaters 30A and 30B similarly arranged on the left and right sides of the heater board, and are collectively formed in a semiconductor process. In this example, as for the temperature detected by the temperature sensor, the average value of the temperatures detected by the temperature sensors 20A and 20B is set as the detected temperature.

FIG. 13 shows an ink jet recording apparatus employing the discharge amount control method of the present invention. This apparatus is a full-color serial type printer having replaceable recording heads corresponding to four color inks of black (Bk), cyan (C), magenta (M), and yellow (Y). The head used in this printer has a resolution of 400 dpi, a driving frequency of 4 KHz, and has 128 ejection ports.

In FIG. 13, reference numeral C denotes four recording head cartridges corresponding to the respective inks of Y, M, C, and Bk. The recording head and an ink tank for storing ink for supplying ink to the recording head are integrally formed. Is formed. Each recording head cartridge C is detachably mounted on the carriage by a configuration (not shown). The carriage 2 is slidably engaged along the guide shaft 11 and is connected to a part of a drive belt 52 that is moved by a main scanning motor (not shown). As a result, the recording head cartridge C can be moved for scanning along the guide shaft 11. 15,
Reference numerals 16, 17, and 18 denote conveying rollers that extend substantially parallel to the guide shaft 11 on the inner side and the lower side in the drawing of the recording area by scanning of the recording head cartridge C. The transport rollers 15, 16 and 17, 18 are driven by a sub-scanning motor (not shown) to transport the recording medium P. The conveyed recording medium P faces the surface of the recording head cartridge C on which the ejection port surface is provided, and forms a recording surface.

FIG. 14 shows Y,
The print timing of four colors of M, C, and Bk is shown. As described above, since the recording head cartridges of the respective colors are mounted on the carriage at predetermined intervals and scan while moving,
Printing of each color to correct the interval between heads of each color,
This is performed at staggered timing.

Next to the recording area of the recording head cartridge C and facing the movable area of the cartridge C,
A recovery system unit is provided. In the recovery unit, 300 is a plurality of cartridges C having a recording head.
The cap units are provided correspondingly to each other, and can be slid in the left and right directions in the figure as the carriage 2 moves, and can be moved up and down in the vertical direction. When the carriage 2 is at the home position,
This is joined to the recording head and capped. In the recovery unit, 401 and 402
First and second blades 403 as wiping members are blade cleaners made of, for example, an absorber for cleaning the first blade 401.

Further, 500 is a cap unit 300
And a pump unit for absorbing ink and the like from the ejection port of the recording head and the vicinity thereof through the recording head.

FIG. 15 is a block diagram showing a configuration example of a control system in the ink jet recording apparatus.

Here, reference numeral 800 denotes a controller constituting a main control unit, which executes, for example, a CPU 801 in the form of a microcomputer for executing the above-described sequence and the like in FIG. 11, programs corresponding to the procedure, tables shown in FIG. A ROM 803 stores pulse voltage values, pulse widths, and other fixed data, and a RAM 805 provided with an area for developing image data, a work area, and the like. Reference numeral 810 denotes a host device (may be a reader unit for image reading) serving as a source of image data, and image data and other commands and status signals are transmitted to and received from the controller via an interface (I / F) 812. .

Reference numeral 820 denotes a power switch 822, a copy switch 824 for instructing the start of recording (copying), and a large recovery switch 82 for instructing activation of a large recovery.
A switch group for receiving an instruction input by the operator, such as 6. Reference numeral 830 denotes a sensor group for detecting the state of the apparatus, such as a sensor 832 for detecting the position of the carriage 2 such as a home position and a start position, and a sensor 834 including a leaf switch 530 and used for detecting a pump position.

Reference numeral 840 denotes a head driver for driving an electrothermal transducer (heater) of a print head (here, only one color is shown) according to print data or the like. Also,
Part of the head driver is also used to drive the temperature heaters 30A and 30B. Further, the temperature sensor 20
The temperature detection values are input to the controller 800 from A and 20B. Reference numeral 850 is a main scanning motor for moving the carriage 2 in the main scanning direction (the left-right direction in FIG. 10), and 852 is its driver. A sub-scanning motor 860 is used to convey (sub-scan) a recording medium.

The recording head mounted on the apparatus shown in FIGS. 13 and 15 is shown below.

FIG. 16 shows an example of the configuration of a head cartridge mountable on the carriage of the ink jet recording apparatus shown in FIG. The cartridge according to the present embodiment has an ink tank unit IT and a head unit IJU integrally, and these are detachable from each other. A wiring connector 102 for receiving a signal and the like for driving the ink ejection unit 101 of the head unit and outputting an ink remaining amount detection signal is provided at a position aligned with the head unit IJU and the ink tank unit IT. . Therefore, in a posture which is taken when the cartridge is mounted on a carriage described later, the height H can be reduced and the thickness of the cartridge can be reduced. This makes it possible to make the carriage small when arranging the cartridges side by side as shown in FIG. When the head cartridge is mounted on the carriage, the knob 2 provided on the ink tank unit IT with the ejection unit 101 facing downward is provided.
01 can be gripped and placed on the carriage.
The knob 201 is engaged with a lever provided on a carriage described later for performing a mounting operation of the cartridge. Then, at the time of mounting, the pins provided on the carriage side engage with the pin engaging portions 103 of the head unit IJU, and the head unit IJU is positioned.

In the head cartridge according to the present embodiment, an absorber 104 for wiping the surface of the ink ejection section 101 and cleaning a member for cleaning the same is arranged in parallel with the ink ejection section 101. Further, an air communication port 203 for introducing air with consumption of ink is provided substantially at the center of the ink tank unit 200.

When various print patterns were printed by the above-described PWM control using the apparatus shown in FIGS. 13 and 15, the density variation in the scan line peculiar to the serial type was eliminated, and the density within the page or between the pages was eliminated. Fluctuations can also be suppressed. In particular, there is no change in the discharge amount caused by the change in the environmental temperature.
As shown in (A), when the pulse width modulation of the pre-heat pulse is performed, the gradation reproducibility of the density (γ curve) becomes constant irrespective of the temperature fluctuation due to the environment and the printing duty. The balance of the color reproducibility reproduced by the color mixture of each of the Y and Bk colors is stabilized, and it becomes possible to provide an excellent full-color image maintaining a constant color reproducibility. FIG. 17B shows a case where the pulse width modulation of the preheat pulse is not performed, and it can be clearly seen from this figure that the reproducibility varies depending on the temperature.

In FIG. 17, the density data of 0 to 255 corresponds to 17 gradation data of gradations 1 to 16.

Further, in this embodiment, the range in which the discharge amount can be modulated by the pulse width modulation corresponds to the temperature range considered to be often used in actual printing, the temperature is controlled by a heater in a low temperature range, and the temperature is controlled in a high temperature range. By using a single pulse that reduces the temperature rise, the discharge amount can be stabilized in a wide usage environment, and the image quality can be stabilized.

(Modification 1) A case where the above-described PWM control is applied to a monochrome serial printer using only a Bk1 color ink with a permanent type recording head will be described below.

The recording head has a resolution of 360 dpi, a driving frequency of 3 KHz, and 64 ejection ports. One temperature sensor is an apparatus using a simplified discharge amount control method that does not perform temperature control. The sequence of pulse width modulation, in which so as to vary the pulse width P ₁ to pulse width P ₁ to detect the average temperature of one scanning line by line.

Even if the control is simplified in this way, since the printer is a monochrome printer using Bk1 color ink, the occurrence of unevenness due to the density difference between lines and the occurrence of streaks at the joints between lines are suppressed, which is effective as simple control. It was confirmed to act on.

(Modification 2) A case in which PWM control is applied to a high-speed printing monochrome printer using a permanent type full multi-nozzle type recording head will be described below.

The recording head has a resolution of 200 dpi, a driving frequency of 2 KHz, and 1600 ejection ports. In accordance with the driving method, one temperature sensor is provided for each block composed of 16 ejection ports of the print head, and a total of 100 temperature sensors are provided. The temperature of each of these temperature sensors is divided into regions for each block, and the pulse width modulation sequence can be controlled independently for each block. As a result, even if a temperature distribution occurs in the recording head due to the existence of the ejection section / non-ejection section peculiar to the full multi, independent ejection amount control can be performed for each block, thereby enabling excellent high-speed printing without density unevenness. became.

Next, the effect of reducing the self-heating of the recording head by printing based on the PWM control of this embodiment will be described below.

FIG. 18 shows the relationship between the preheat pulse width P ₁ and the self-heating temperature T _UP of the recording head by printing. The printing duty is changed from 25% to 100% every 25%. Also, the values of the self-heating T _UP indicate data in the case of printing one line. Self heating T _UP by the print recording head, as the preheat pulse P ₁ is large, also, (number of discharges per number ejection nozzle or unit time) printing duty it can be seen that is increasingly higher. That is, it is sufficient so as not to self warm to shorten actively pulse width of the preheat pulse P ₁ when the printing duty is high. Therefore, in this example, the print duty is high, and since the temperature of the head increases at the same time as the print time increases, the print head temperature is detected near the discharge heater of the print head,
Controlling the preheating pulses P ₁ on the basis of the temperature.
As described above, by using the PWM control, the self-heating can be efficiently reduced.

FIG. 19 shows each printing duty (1 in FIG. 19).
(25%, 2 corresponds to 50%, 3 corresponds to 75%, and 4 corresponds to 100%). Further, in FIG. 19, a shows the case in which printing is performed with a pulse width fixed mode, b is the pre-heat pulse P ₁ PW
This is a mode when printing is performed by giving an optimum pulse according to the head temperature by M control. From this figure, it can be seen that performing the PWM control has the effect of effectively lowering the self-heating of the head particularly during high-duty printing and at high temperatures.

This is because, for example, when printing is performed at each duty shown in FIG.
By PWM control, there by preheating pulses P ₁ was reduced thermal energy applied per unit time by reducing in the direction of arrow a in FIG. 18 self heating rate due to the printing head is lowered.

(Modification 3) Next, an example in which the present invention is applied to a color printer using a permanent recording head will be described below, particularly with respect to self-heating suppression.

In this embodiment, the pulse table is not divided into a fixed temperature range as shown in FIG. 10 of the first embodiment, but the higher the temperature of the recording head, the faster the pulse switching. It is something that can be done. That is, when the recording head is at a relatively low temperature, the temperature step width of pulse switching ± ΔT, that is, the temperature width of the preheat table as shown in FIG. 10 is increased, and the pulse switching is performed as the recording head temperature increases. By narrowing the temperature step width. +-.. DELTA.T, the self-heating rate by printing on the high temperature side can be more effectively reduced.

This control is performed in the PWM range shown in FIG. 8 when the head temperature T _H is between 26.0 ° C. and 44.0 ° C. The temperature is detected as a temperature, and based on the temperature, a temperature step width ± ΔT4.0 according to a table condition shown in FIG.
The preheat pulse width P1 is changed from 1.0 ° C. to 1.0 ° C. This control follows the sequence shown in FIG.

As the recording head, the low temperature side (from room temperature to 40
(Up to about ℃), but due to its nature at high temperatures, it is structurally sensitive to heat and can be said to be the fate of heating-type inkjet (foaming stability) In this temperature range, it is preferable to avoid use as much as possible because the characteristics and refill frequency characteristics have a large effect. Therefore, it is desirable to control so as not to reach the high temperature side as much as possible.

According to the control table shown in FIG. 20, as the head temperature becomes higher, the preheat pulse P ₁ becomes higher.
Can be switched, it is possible to further suppress the self-heating caused by printing on the high temperature side.

This state is shown in FIG. In the drawing, a shows a self-heating curve when the third modification is applied, and b shows a self-heating curve when the temperature width at which the preheat pulse width P1 is switched is made constant.

As can be seen from the figure, according to the third modification, the self-temperature rise by printing is large when the head temperature is relatively low (less than 40 ° C.), but after the intersection C, the tendency reverses. The head temperature further rises and the high temperature side (40 ° C
Upon reaching the above) are of the pulse pre-heat pulse P _1, the self Atsushi Nobori is suppressed to you have devised to dampen self temperature Yutakaritsu by rapid switching.

In this example, the temperature range is changed as shown in FIG. 10, but it is desirable to change the temperature range appropriately according to each use condition.

(Modification 4) An example in which the present invention is applied to a monochrome printer will be described below in particular with respect to self-heating suppression.

This printer uses an exchangeable recording head, and it is desirable to set optimum discharge amount control conditions (control temperature width / control pulse width) for the recording head every time the recording head is replaced. In this case, since the printer is a monochrome printer, a relatively coarse discharge amount control is possible. Therefore, by increasing the decreasing rate of the value of the preheat pulse width P1 as the temperature becomes higher, the self-heating of the recording head can be suppressed.

[0118] That is, as is clear from the control table shown in FIG. 22, according to this table, the high temperature side because the head temperature was increased pulse variation of the pre-heat pulse P ₁ at the time the more pulse switching if a high temperature It has become possible to further suppress the self-heating caused by printing in the. This situation is qualitatively the same as that shown in FIG.

As is apparent from the above description, according to the present invention, for example, when the heating element of the recording head is driven by a plurality of pulses of two pulses, the first pulse is generated according to the temperature of the recording head. By performing a pulse energy change such as width modulation, the ejection amount is controlled, and the temperature rise of the recording head is prevented.

As a result, the thermal energy applied to the heating elements is minimized, the self-heating of the head, which occurs during printing, is reduced, the discharge amount can be controlled, and the density fluctuation and the color balance can be stabilized.

In addition, variations in the ejection amount as adverse effects caused by the self-heating of the head, changes in the ejection characteristics during printing due to changes in the ink temperature, and control characteristics due to changes in the structure of the head result in deflection, non-ejection, and a decrease in the refill frequency. It has become possible to eliminate various phenomena that have extremely deteriorated the image.

As a secondary effect due to the decrease in the head temperature, the life of the head can be drastically increased.

As the recording head temperature detecting means, the following can be applied to the present invention. That is, means for directly detecting the temperature of the recording head, which may use an abutting or non-contacting sensor from the outside, may preferably be formed integrally with a substrate having a heating element of the recording head. good. Alternatively, a means for indirectly estimating the printhead temperature, for example, a means for estimating the temperature related to the drive of the printhead from detection of the temperature of a control (CPU, capacitor, etc.) device or the like. The advantage of this estimating means is that there is no variation in temperature detection, and stability can be obtained because the same temperature sensor is normally used by the main unit.

As means for selecting (changing or changing) the waveform of the drive signal, the following can be applied to the present invention.

As the basic waveforms, those represented in FIG. 9 can be cited. The leading portion P _{1 of} the drive signal and the drive pause period P _1
2, when the main drive portion P _3, the selection of the waveform, changes, as the changes, changed in accordance with the preceding portion P ₁ of the pulse width (application time) the one that changes according to temperature and dwell time P ₂ temperature one which and include those changing the ratio of the preceding portion P ₁ and the driving pause time P ₂ in the time constant drive signal.

In the present invention, the main drive pulse P ₃ is fixed,
Leading pulse is P ₁ a is preferably what gives 0 and a predetermined time is also intended to be within the spirit of the present invention is that by changing the main drive pulse P _3.

[0127] In the above description, a driving pause time P ₂ are listed the most preferred form as the period of zero voltage, may be used as the constant voltage supply periods of low level from P _1, P _3, also, the pulse The voltage may be supplied by switching the waveforms of P ₁ and P ₃ as a sine waveform.

In terms of circuit, a combination of a preceding pulse layer generator and a main drive pulse P ₃ generator, or a method of partially selecting a signal from a constant pulse generator and supplying it to a heating element or an electrothermal conversion element Alternatively, various types of devices can be used, such as those for selecting or designating the supply timing of the preceding pulse P ₁ and the main drive pulse P ₃ and supplying them to the electrothermal converter or the like.

The driving signal means an entire signal that causes an on-demand bubble formation effect on the electrothermal transducer.
When this drive signal has a plurality of pulse components as described above, expressions of a preceding pulse and a main pulse will be taken. The preceding pulse may be a plurality of preceding pulses. When there are a plurality of preceding pulses, they may be expressed as a plurality of drive signals. When there are a plurality of preceding pulses, the pause period refers to an interval between the last preceding pulse and the main pulse.

(Embodiment 2) Next, a description will be given of a method of correcting variations in the ejection amount of each head, which are caused by the head manufacturing process. FIG. 23, FIG. 24, and FIG. 25 are flowcharts showing main control of the ink jet recording apparatus according to one embodiment of the present invention. First, the outline of the main control will be described using a flowchart.

In the figure, the power is turned on, and the apparatus performs an initial check of the apparatus in step S1. This check is to check the ROM and RAM of the apparatus, that is, check programs and data to confirm whether the apparatus can operate normally. In step S2, a correction value of the temperature sensor circuit is read. In step S3, an initial jam check is performed. In this embodiment, even when the front door is closed, an initial jam check is performed in step S3.
In step S4, a check on the device side necessary for reading the information of the recording head in the next step is performed. In step S5, data in a ROM built in the recording head is read. Next, initial data is set in step S6.

In step S7, the initial temperature control at 20 ° C. is started, and in step S8, a recovery operation determination [1] (determination of whether or not to perform a suction recovery operation when the power is turned on) is performed.

FIG. 26A shows the flow of the initial temperature control routine at 20 ° C. After setting the timer counter for 30 seconds in step S2001, if the temperature is higher than 20 ° C., the routine ends (step S2002). If the temperature is lower than 20 ° C., the heater of the head is turned on in step S2003. In step S2004, it is checked whether the timer has expired for 30 seconds. If 30 seconds have elapsed, the operation is abnormally stopped in step S2005. If not, the process returns to step S2002.

The above is the recording standby state (wait state).
This is the sequence flow description up to this point.

Next, a sequence flow in the standby state will be described. In step S9, the temperature is controlled at 20 ° C., and in step S10, standby idle discharge is performed. In step S11, it is checked whether there is no paper feed. If there is no paper feed, the process proceeds to step S21. It is checked in step S12 whether the cleaning button has been pressed, and if so, the cleaning operation is performed in step S13. If the RHS button has been pressed in step S14, the RHS mode flag is set in step S15. Here, RHS refers to a head shading process for correcting density unevenness of a recording head. The density unevenness of a printed pattern is read by a reading unit (reader) to correct the density unevenness.

If manual paper is fed in step S16, a manual feed flag is set in step S17, and the flow advances to step S22, which is a copy start sequence. If the OHP button is turned on in step S18, step S1
In step 9, the OHP mode flag is set, and if not turned on, the OHP mode flag is reset in step S20. If the copy button is pressed in step S21, the process proceeds to step S22, which is a copy start sequence. On the other hand, if it has not been pressed, the process returns to step S9. When the cleaning operation is completed in step S13, the process returns to step S9.

Next, the copy sequence will be described. In step S22, the fan for suppressing the temperature rise in the apparatus is rotated, and in step S23, the temperature control at 25 ° C. is started. Step S
At 24, it is checked whether or not the paper is fed.
Performs idle discharge [1] (N = 100) in step S29.
Proceed to. Here, N indicates the number of times of idle discharge. Step S
At 26, a recovery operation determination [2] (determination of whether or not to perform a suction recovery operation before paper feeding) is performed, and paper feeding is performed at the next step S27. In step S28, a paper width and paper type detection operation is performed. In step S29, it is checked whether to move the image. If an image bequest is to be performed, the sub-scanning movement (paper movement) is performed in step S30. If the image is not to be moved, the process proceeds to step S31. In step S31, it is checked whether the temperature of the write head has reached 25 ° C. or higher. If the temperature is equal to or higher than 25 ° C., a recovery operation determination [3] (a determination as to whether or not to perform the recovery operation based on the amount of ink evaporation in the non-capping state) is made in step S32, and a one-line portion is determined in step S33. Perform the recording operation. Then, in step S34, the recovery operation is determined [6].
(Determining whether to perform a recovery operation based on the wiping timing) is performed, and the sheet is conveyed in step S35.

In the step S36, it is checked whether or not the recording operation has been completed. If completed, data such as the number of prints is written into the ROM of the head, and then the process proceeds to step S37. If not, the process returns to step S31. In step S37, it is checked whether or not to shift to the standby state.

[0139] From step S38, the paper discharging operation and 1
This is a routine for performing recovery operation determination [4] (removal of print bubbles, removal of bubbles in the liquid chamber, cooling and recovery at abnormally high temperatures) after printing of one sheet. In step S38, it is checked whether or not there is a sheet discharging operation.
If there is no paper discharging operation, steps S39, S40, S41
Then, wait for the temperature to drop to 45 ° C. or less, and if the temperature does not drop within 2 minutes, stop the abnormality in step S42. If the temperature falls below 45 ° C., the wiping operation is performed in step S50, the idle discharge operation (N = 50) is performed in step S43, and the capping is performed in the next step S48. If there is a paper discharging operation, the paper discharging operation is performed in step S44. In step S45, it is checked whether continuous printing is performed. If continuous printing is performed, the process returns to step S24 after the recovery operation determination [4] in step S47. If it is not continuous printing, recovery operation determination [4] in step S46 is performed, and after the determination, capping is performed in step S48 as in the case where there is no paper ejection. Then, in step S49, the fan is stopped, the process returns to step S9, and the copy operation ends.

FIGS. 26B and 26C are flow charts of the 20 ° C. temperature control and 25 ° C. temperature control routines. Step S21
At 01, it is checked whether the head temperature is higher or lower than 20 ° C. If it is higher than 20 ° C., the heater of the head is turned off in step S2102, and if it is lower than 20 ° C., the heater of the head is turned on in step S2103, and the 20 ° C. temperature control routine ends. Steps S2104 to S2106 in the 25 ° C. temperature control routine are also
Steps S2101 to S210 in the ° C temperature control routine
3, the description is omitted.

FIG. 27 is a flowchart showing details of the initial jam check routine in step S3. This routine is a jam detection immediately after the power is turned on. In steps S201 to S204, a paper feed sensor, a paper discharge sensor, a paper float detection sensor, and a paper width sensor are used to check whether recording paper or the like is in the transport path or near the carriage. If so, it is determined to be a jam and a warning is issued; otherwise, the process returns to the main flow.

FIG. 28 is a flowchart showing details of the head information reading routine of step S5. In step S301, the serial No. unique to the head of the writing head is set. And read the serial No. Is checked whether the value is FFFFH (step S302). Serial N
o. Is not FFFFH, it is determined in step S304 that there is no head and an error occurs. Serial No. Is FF
If it is not FFH, the color information of the head is read in step S303. In step S305, it is checked from the color information whether the head is mounted at a regular position designated for each color.
To 06, if it is incorrectly attached, the process proceeds to step S307.

In step S306, the remaining head information (print pulse width, temperature sensor correction value, number of prints, number of wiping, etc.) is read and stored. Step S308
Then, the serial No. of the head determines whether the attached write head is new. Find out by comparing. Serial No. of the head Is always backup RAM
And can be compared with the data read from the head. If the values are different, a new head is mounted, and if the values are equal, it can be determined that the head has not been replaced. In this embodiment, the processing is performed for each of Bk, C, M, and Y colors. If the head is not a new head, the head information reading routine ends. If it is a new head, the new head information (serial No., color information, print pulse width, PWM pointer No., temperature sensor correction item, number of prints, number of wipings, etc.) is stored in the memory of the apparatus in step S309. Then, a flag (or data) indicating that a new head is mounted is set in the memory. Next, in step S310, the HS data (shading information) of the write head is read, and in step S311.
Then, the time when the use of the new head is started is written from the clock in the apparatus to the non-volatile memory in the head, and the head information reading routine ends.

Here, a ROM serving as information storage means of the head
How to use is explained in detail.

(Drive Setting) The apparatus used in this embodiment uses a recording head (cartridge type) which can be exchangeably mounted, and has an advantage that the user can exchange the recording head at any time. Further, since this head is supplied by mass production, individual heads have different characteristics due to variations in the manufacturing process. Therefore, in order to more stably obtain high image quality, it is necessary to correct variations in the above characteristics.

As a method of correcting such a difference in the setting of the driving conditions for each head, correction by reading the driving conditions for each head stored in the ROM of the head, and correction for one head due to the distribution of the ejection hole diameter of the head. Head shading (HS), which is a method for correcting the density unevenness due to the variation in the ejection amount in the above, is performed.

When such correction is not performed for each head, among the discharge characteristics, the discharge speed, the discharge direction (landing accuracy), the discharge amount (density), the discharge stability (refill frequency, unevenness, sliminess), etc. Is not optimized. For this reason, not only is it difficult to obtain a stable high-quality image, but there is a fear that non-discharge or remarkable image disturbance may occur during printing.

In particular, full-color images are C, M,
Since the image is formed by the four heads Y and Bk, printing with a head having a discharge amount and control characteristics different from those in the standard state even for one color may cause an image trouble. Above all, the variation in the discharge amount causes a change in color tone and color reproducibility (increase in color difference) due to the collapse of the overall color balance, thereby deteriorating the image quality. In a monochromatic image such as black, red, blue, or green, a density fluctuation occurs. In addition, the variation in the control characteristics changes the halftone reproducibility. In the present embodiment, these variations in the ejection characteristics are corrected.

The head driving of this embodiment uses the divided pulse width modulation driving method described in the first embodiment. The head structure is the same as the head used in the first embodiment. The head in this embodiment is a ROM in which characteristics of each head are recorded.
(EEPROM), and by reading this information into the main body, variations in the characteristics of individual heads are corrected.

A method for obtaining an optimal and high-definition image by correcting the variation in the ejection characteristics of each head will be described below. As described above, when power is applied to the main body on which the head is mounted, information (ROM information) stored in the head ROM at the time of manufacturing the head is read into the main body. At this time, the head ID number, color information, T _A1 (header driving condition table pointer corresponding to the print pulse width), T _A3 (P
Information such as a WM table pointer), a temperature sensor correction value, the number of printed sheets, and the number of times of wiping are read. According to the table pointer T _A1 read here, the main body calculates the value of the main heat pulse width (P ₃ ) in the divided pulse width modulation drive control method described later. The details are shown below.

[0151] (1) T _A1 determined: at the time of manufacture of the head, in advance standard driving condition (head temperature discharge characteristic measurement of each head; T _H = 25.0 (environment in driving voltage ° C.); V _OP =
At 18.0 (V), P ₁ = 1.87 (μsec) and P ₃
= 4.114 (μsec) pulse), and the optimal drive conditions for each head are determined, and the RO of the head is determined.
The information is stored in M as information.

(2) Driving condition setting: On the main unit side, each pulse width at the time of divided pulse width driving Preheat pulse width; P ₁ , interval time width; P ₂ , main heat pulse width;
_In order to set ₃ , the time from the rise of the preheat pulse is set to T ₁ , T ₂ , and T _{3 as} shown in FIG. 1, and the value of T ₃ (T ₃ = 8.602 μsec) is initially set on the main body. From the fixed. Pulse width condition T ₂ given by the pointer read from the head; T _A1 (for example, T 1
According to the value of _A1 = 4.488 μsec, P ₃ (P ₃ = T
₃ −T ₂ = 4.114 μsec).

FIG. 29 shows table pointers; T _A1 and T _A1.
The relationship with the main heat pulse width (P ₃ ) obtained from FIG.

(Method of Correction by PWM) Here, a method of using a PWM control method for correcting variations in the discharge amount of each head and performing optimum image formation in the present invention will be described. The PWM control conditions are read into the main body on which the head is mounted when the power is turned on, along with the ID number, color, driving conditions, and HS data as ROM information of the head.

In this embodiment, a table pointer: T _A3 is read as a PWM control condition. As will be described later, the number T _A3 is assigned a number corresponding to the discharge amount (V _DM ) of the head, and the main body side sets the upper limit value of the PWM preheat pulse width: P ₁ according to the read T _A3. Decide. Next, a correction method using PWM will be described in order.

(1) Determination of the table pointer T _A3 : The discharge amount of each head is measured in advance in the process of manufacturing the head during the manufacturing process under a standard driving condition (head temperature; T _H = 25.0 (° C.)). Voltage; P ₁ = when V _OP = 18.0 (V)
P ₃ = 4.114 (μsec) at 1.87 (μsec)
The pulse is applied), and the value is defined as a measured discharge; _VDM . Next, the standard discharge amount; V _OP = 30.0 (ng / do)
The difference from t) is determined as ΔV = V _DO −V _DM . This ΔV
From the value of ΔV and the table pointer as shown in FIG.
We asked for a relationship with _A3 . In this way, the ranks are classified according to the amount of the ejection amount, and the T _A3 for each head is stored as information in each ROM.

[0157] When creating a table from [Delta] V is 1 table of variation of the controllable preheat pulse width P ₁ in the divided pulse width modulation driving method to be described later; should be the same as the [Delta] V _P. That is because doing the ejection amount correction of the head by the pre-heat pulse width P ₁ as described later.

(2) Reading the table pointer: The head having the information stored in the ROM of the head is mounted on the main body of the ink jet recording apparatus as shown in (1) above, and when the power is turned on, as shown in FIG. The information stored in the head ROM is stored in the S
Store in RAM.

(3) Determination of table for PWM control: A head having a large discharge amount (for example, V _DM = 31.2 [ng]
/ Dot]), the environmental temperature (head temperature) is 25.0.
The value of the pre-heat pulse width P ₁ when the ℃ made shorter than the standard driving condition (P ₁ = 1.867μsec) (e.g. P
₁ = 1.496 μsec) The discharge amount is reduced to approach the standard discharge amount V _DO = 30.0 [ng / dot].

2. A head with a small discharge amount (for example, V _DM =
28.8 [ng / dot]), the value of the preheat pulse width P ₁ when the environmental temperature (head temperature) is 25.0 ° C. is made longer than the standard driving condition (P ₁ = 1.867 μsec) (for example, 2.244 μsec) Increase the discharge amount to approach the standard discharge amount V _DO .

[0161] 3. As shown in FIG. 30, the above operation is performed according to the table pointer T _A3 according to the ejection amount of each head.
And are determined in relation preheat pulse width P ₁ is Aru always set to be the standard ejection amount V _DO.

4. According to such a method, the main body side performs PWM with respect to the standard discharge amount V _DO (30.0 ng / dot).
Since it is possible to have 16 tables, the width of the ejection amount for adjusting one pointer is set to 0.6 (ng) as shown in FIG.
/ Dot), it is possible in principle to correct the ejection amount variation of ± 4.8 (ng / dot) as a whole, but actually, the ejection amount control method described above is used. In order to effectively use the above, it is preferable to correct the variation in the ejection amount of about ± 1.8 (ng / dot).

[0163] This means, will then generate up foam when the preheat pulse P ₁ as shown in FIG. 3 too large,
This is because if P ₁ is too small, the temperature range of the discharge amount control by PWM becomes narrow, which is not preferable.

In this embodiment, the density and the color reproduction range of the image design
From the viewpoint of P, as shown in FIG. ₁ Changes in 5 stages
I am holding it down. Therefore, the ink ejection amount and white streak
Standard ejection amount: V as a regular head in terms of image quality_DO
= 30.0 ± 2.0 (ng / dot)
Although this correction method was not used,_DO'=
Available up to 30.0 ± 3.8 (ng / dot)
It became.

As described above, by reading the PWM control table pointer T _A3 as the head ROM information and changing the set conditions (drive conditions) on the main body side, it is possible to absorb the variation in the discharge amount of each head. In addition, the color chamber can be easily stabilized even in a main body using a recording head mounted so as to be exchangeable. Further, since the yield of the head can be improved, the cost of the cartridge head can be reduced.

The preheat pulse width P ₁ may be changed by changing the value of P ₁ for each appropriate range of the head temperature T _H as shown in FIG. 31 or by following the sequence shown in FIG.

[0167] Note that in FIG. 31 (A), and the reference value of the P ₁ shows the case of the P ₁ = 0A, the pre-heat pulse width P ₁ 1 step (1H) is increments vary 2.0 ° C. I have. The figure (B), (C) is the reference value of the P ₁ P
_{The case where 1} = 0B or P ₁ = 09 is shown. Note that these reference values may be stored in the ROM of the head and read out by the apparatus main body to create a table, or the head may be stored in a table having different reference values stored in the apparatus main body. May be selected based on the ROM information.

FIG. 32A is a diagram showing the appearance of the ink jet cartridge of this embodiment. FIG. 2B is a diagram showing details of the printed board 85 of FIG. 1A. In FIG. 8B, reference numeral 851 denotes a printed circuit board;
52 is an aluminum heat radiating plate, 853 is a heater board composed of a heating element and a diode matrix, 854 is an EEPROM (non-volatile memory) storing density unevenness information and the like in advance, and 855 is a contact electrode serving as a joint with the main body. is there. Here, the discharge port group of the line is not shown.

Thus, the ink jet recording head 8
An EEPROM 854 for storing density unevenness information and the like unique to each recording head is mounted on a printed circuit board 851 including a heating element b and a drive control unit. In this way, when the recording head 8b is mounted on the main unit, the main unit reads out information on recording head characteristics such as density unevenness from the recording head 8b, and performs predetermined control for improving recording characteristics based on this information. I do. This makes it possible to ensure high quality image quality.

FIGS. 33 (A) and (B) are diagrams showing the main circuit configuration on the printed board 851 of FIG. here,
The circuit configuration inside the heater board 853 is indicated by a dashed-dotted line. The heater board 853 has a N × M (here, 16 × 8) circuit of a series connection circuit of a heating element 857 and a diode 856 for preventing current from flowing around. It has a matrix structure. That is, these heating elements 857 are
As shown in FIG. 34, each block is driven in a time-division manner,
The control of the supply amount of the driving energy is performed by the segment (se
This is realized by changing and controlling the pulse width (T) applied to the g) side.

FIG. 33 (B) shows the EEPROM of FIG. 32 (B).
FIG. 8 is a diagram illustrating an example of M854, in which information on density unevenness and the like according to the present embodiment is stored. These information are output to the main device by serial communication in response to a request signal (address signal) D ₁ from the main body device side.

In addition, it has been described that the information of each head is stored in the ROM and the variation of the ejection characteristics of each head is corrected. However, a means for transmitting the information to the main body may be used.

FIGS. 35A and 35B are diagrams showing examples of other heads. In this head, as a means for changing the information to the main body side as described in the above example, a plurality of concave and convex shapes are provided on the head chip instead of the ROM of the head so that the information can be transmitted in this combination. . FIG. 35 (A) shows information transmitting means using a combination of projection shapes, and FIG. 35 (B) shows information transmitting means using a combination of hole shapes. With such a head shape, information can be transmitted in a simple and low-cost manner. When the head is mounted on the main body, the main body reads information such as a table pointer or a table based on the uneven shape provided on the head mechanically, electrically, or optically to change the control condition.
In this printer, a replaceable recording head is used, and it is desirable to set an optimum control condition for the head every time the head is replaced. Note that these configurations are not limited to the configuration in FIG. 35, and may be notches or the like, and needless to say, any configuration may be used as long as they perform the same function.

The heads shown in FIGS. 3 and 4 are different from each other because there are differences in the discharge characteristics that occur during the manufacturing process. That is, the head temperature (T _H) preheat pulse under certain conditions; P ₁ and the discharge amount: relationship between V _D is, b in FIG. 3
(Or c) foaming the main heat pulse P ₃ is the prefoaming phenomenon P _1LMT until the slope is large (small slope) linearly increased later with increasing pulse width P _1, as shown in When _P1MAXb ( _P1MAXc ) is disturbed, the ejection amount tends to decrease. Preheat pulse; P
₁ head temperature under certain conditions; T _H (environmental temperature) and the ejection amount; relationship between V _D, the slope increases with increasing head temperature T _H as shown in b (or c) in FIG. 4 It shows a tendency to (small) increase linearly. The coefficients of the regions showing the linearity are the preheat pulse dependence coefficient of the ejection amount: K _{P ′} = ΔV _DP / ΔP ₁ (ng / us · dot) The head temperature dependence coefficient of the ejection amount: K _TH = ΔV _DT / ΔT _H (ng
/ C · dot). Even with the head structure shown in FIG. 2, K _P = 3.5 for a head like b in FIG.
3 (ng / μsec · dot) · K _TH = 0.35 (ng
/ Μsec · dot). In the head as shown in FIG. 4C, K _P = 3.01 (ng / μsec · dot) ·
K _{TH was} 0.25 (ng / μsec · dot).

As described above, in order to effectively perform the discharge amount control based on these two relations, since the relation shown in FIG. 8 differs in the case of b or c, the temperature width and the pulse width of the control must be changed. Need to optimize. As described above, the main unit reads and sets the optimized control conditions, so that when the head is replaced, the initial ejection amount is corrected and the control during printing is changed. Therefore, even if the head temperature changes due to various factors such as a change in environmental temperature or a change due to self-heating caused by printing, a discharge amount control method capable of keeping the ink discharge amount of the head constant at all times becomes possible. In this embodiment, the head chip is provided with a discriminating function. However, the same configuration may be used for the ink tank for discrimination.

When the permanent head is applied to a color printer, adjustments are made at the time of shipment of the main body, so that all adjustments must be completed easily and in a short time. Conventionally, since the difference in recording density with respect to the input signal differs for each head, the gamma correction for correcting this difference is changed for each of the C, M, Y, and Bk heads.
By adjusting the color balance, a reduction in color reproducibility due to variations in the ejection amount was suppressed. By this method, it was possible to adjust the halftone color balance, but it was not possible to perform basic ejection amount correction in the solid printing state. Further, if the correction is performed by changing the gamma correction, the density is reduced.

By applying the present invention, the ejection amount can be corrected by automatically reading the correction data from the head at the time of assembly, so that it is not necessary to change the gamma correction forcibly. In addition, since the permanent head has the same life as the main body of the ink jet recording apparatus, if a change in the discharge amount occurs while using this apparatus, the head has conventionally been replaced by replacing the head. By using it, it became easy to adjust.

As described above, according to the present embodiment,
In an ink jet recording apparatus using a particularly replaceable head among the ink jet recording heads, some type of information transmission means is provided in the head, and the recording apparatus main body receives information stored in the information transmission means of the head and performs divided pulse width modulation driving. by changing the PWM of the pointer or table used by law preheat pulse width; by changing the value of P _1, changing the discharge amount of the head to correct the ejection amount variation of each head, generated in the manufacturing process of the head initial It has become possible to absorb variations in the discharge amount. As a result, it is possible to improve the image quality by eliminating the variation in the ejection amount of each head and eliminating the change in color and the decrease in color reproducibility (increase in color difference) due to the disturbance of the color balance that occurred in the full-color image. . Further, by changing the control characteristics, the halftone reproducibility of color can be improved, and the density fluctuation can be eliminated in a monochrome image such as Bk, red, blue, or green. Also, by adopting this method, it is possible to sufficiently use a head which has been difficult to use because of an excessive or insufficient discharge amount, and it is possible to significantly improve the yield of the head and reduce the head cost. It has become possible.

In each of the embodiments described above, the method of controlling the discharge amount to be stable in accordance with the output of the temperature sensor has been described.
However, the present invention is not limited to this. For example, the ejection amount may be changed by a gradation signal for instructing the gradation of the recording dot. Furthermore, based on the temperature change detected by the sensor, the ejection amount may be changed in accordance with the gradation signal to stably change over a wide range.

(Others) The present invention includes a means (for example, an electrothermal converter, a laser beam, or the like) for generating thermal energy as energy used for performing ink ejection, particularly in an ink jet recording system. An excellent effect is obtained in a recording head and a recording apparatus of a type in which the state of ink is changed by the thermal energy. This is because according to such a method, it is possible to achieve higher density and higher definition of recording.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method is a so-called on-demand type,
Although it can be applied to any type of continuous type, in particular, in the case of the on-demand type, it can be applied to a sheet holding liquid (ink) or an electrothermal converter arranged corresponding to the liquid path. By applying at least one drive signal corresponding to the recorded information and giving a rapid temperature rise exceeding the nucleate boiling, heat energy is generated in the electrothermal transducer, and film boiling occurs on the heat acting surface of the recording head. Liquid (ink) corresponding to this drive signal on a one-to-one basis.
This is effective because air bubbles inside can be formed. The liquid (ink) is ejected through the ejection opening by the growth and contraction of the bubble to form at least one droplet. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further, if the conditions described in US Pat. No. 4,313,124 relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination of the discharge port, the liquid path, and the electrothermal converter (linear liquid flow path or right-angled liquid flow path) as disclosed in the above-mentioned specifications, U.S. Pat. No. 4,558,333 and U.S. Pat. No. 44,558 which disclose a configuration in which a heat acting portion is arranged in a bending region.
A configuration using the specification of Japanese Patent No. 59600 is also included in the present invention. In addition, Japanese Unexamined Patent Application Publication No. 59-123670 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal transducer for a plurality of electrothermal transducers, and an aperture for absorbing a pressure wave of thermal energy is provided. The effect of the present invention is effective even if the configuration is based on JP-A-59-138461, which discloses a configuration corresponding to a discharge unit. That is, according to the present invention, recording can be reliably and efficiently performed regardless of the form of the recording head.

Further, the present invention can be effectively applied to a full-line type recording head having a length corresponding to the maximum width of a recording medium on which a recording apparatus can record. Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads, or a configuration as one integrally formed recording head.

In addition, even in the case of the serial type as described above, a recording head fixed to the apparatus main body, or an electric connection with the apparatus main body or ink from the apparatus main body is mounted on the apparatus main body. The present invention is also effective when a replaceable chip-type recording head that can be supplied or a cartridge-type recording head in which an ink tank is provided integrally with the recording head itself is used.

It is preferable to add ejection recovery means for the recording head, preliminary auxiliary means, and the like as the configuration of the recording apparatus of the present invention since the effects of the present invention can be further stabilized. If these are specifically mentioned, the recording head is heated using capping means, cleaning means, pressurizing or suction means, an electrothermal transducer, another heating element or a combination thereof. Pre-heating means for performing the pre-heating and pre-discharging means for performing the discharging other than the recording can be used.

The types and the number of recording heads to be mounted are not limited to those provided only for one color ink, for example, and for a plurality of inks having different recording colors and densities. A plurality may be provided. That is, for example, the printing mode of the printing apparatus is not limited to a printing mode of only a mainstream color such as black, but may be any of integrally forming a printing head or a combination of a plurality of printing heads. The present invention is also very effective for an apparatus provided with at least one of the recording modes of full color by color mixture.

In addition, in the embodiments of the present invention described above, the ink is described as a liquid. However, an ink which solidifies at room temperature or lower and which softens or liquefies at room temperature may be used. In general, the ink jet method generally controls the temperature of the ink itself within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. Sometimes, the ink may be in a liquid state. In addition, in order to positively prevent temperature rise due to thermal energy by using it as energy for changing the state of the ink from a solid state to a liquid state, or to prevent evaporation of the ink, the ink is solidified in a standing state and heated. May be used. In any case, the application of heat energy causes the ink to be liquefied by the application of the heat energy according to the recording signal and the liquid ink to be ejected, or to start solidifying when it reaches the recording medium. The present invention is also applicable to a case where an ink having a property of liquefying for the first time is used. In such a case, the ink
JP-A-54-56847 or JP-A-60-7
As described in Japanese Patent Publication No. 1260, it is also possible to adopt a form in which the sheet is opposed to the electrothermal converter in a state where it is held as a liquid or solid substance in the concave portion or through hole of the porous sheet. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, the form of the ink jet recording apparatus of the present invention is not only used as an image output terminal of an information processing apparatus such as a computer, but also for a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmission / reception function. It may take a form.

[0189]

As is clear from the above description, according to the present invention, the discharge amount can be stabilized irrespective of a change in environmental temperature or a change in temperature due to a rise in temperature (self-heating) due to printing.

[Brief description of the drawings]

FIG. 1 is a view showing a pulse waveform of a pulse width modulation driving method of a divided pulse according to an embodiment of the present invention.

FIGS. 2A and 2B are a cross-sectional view and a front view, respectively, of a recording head used in Examples.

FIG. 3 is a diagram showing a relationship between a discharge amount and a pulse width according to the present invention.

FIG. 4 is a diagram showing a relationship between a discharge amount and a head temperature.

FIG. 5 is a diagram for explaining the principle of the divided pulse width modulation driving method according to the present invention.

FIG. 6 is a diagram for explaining the principle of the divided pulse width modulation driving method according to the present invention.

FIG. 7 is a diagram for explaining the principle of the divided pulse width modulation driving method according to the present invention.

FIG. 8 is an explanatory diagram of a discharge amount control method according to one embodiment of the present invention.

FIG. 9 is a waveform diagram of pulses set in a table according to one embodiment of the present invention.

FIG. 10 is a diagram showing a head temperature and a preheat pulse modulation control table corresponding to the head temperature according to the embodiment of the present invention.

FIG. 11 is a flowchart of a pulse width modulation sequence according to one embodiment of the present invention.

FIG. 12 is a schematic top view of a heater board used in one example of the present invention.

FIG. 13 is a perspective view of a color printer according to one embodiment of the present invention.

FIG. 14 is a diagram illustrating printing timing of each color when performing full-color printing.

FIG. 15 is a block diagram showing a control structure of the printer according to one embodiment of the present invention.

FIG. 16 is a perspective view of a recording head cartridge mounted on the printer.

17 (A) and (B) are diagrams showing an example of the present invention and a conventional example, respectively, showing gradation reproducibility.

FIG. 18 is a diagram showing the relationship between the preheat pulse width and the self-heating of the recording head for each print duty according to one embodiment of the present invention.

FIG. 19 is a diagram similarly showing a relationship between a printing time and a self-heating.

FIG. 20 is an explanatory diagram showing a preheat pulse modulation control table according to another embodiment of the present invention.

FIG. 21 is a diagram showing the relationship between the print time and the self-heating of the head when the table is used.

FIG. 22 is a diagram showing a preheat pulse modulation control table according to still another embodiment of the present invention.

FIG. 23 is a flowchart showing main control of the ink jet recording apparatus according to one embodiment of the present invention.

FIG. 24 is a flowchart showing main control of the ink jet recording apparatus according to one embodiment of the present invention.

FIG. 25 is a flowchart showing main control of the ink jet recording apparatus according to one embodiment of the present invention.

FIGS. 26A, 26B, and 26C are flowcharts illustrating initial temperature control at 20 ° C., temperature control at 20 ° C., and temperature control at 25 ° C., respectively, according to an embodiment of the present invention.

FIG. 27 is a flowchart showing details of an initial jam check routine in step S4 in the above flowchart.

FIG. 28 is a flowchart showing details of a head information reading routine of step S5 in the above flowchart.

29 is a diagram showing the relationship between the main heat pulse width P ₃ obtained from the table pointer T _A1 and T _A2.

30 is a diagram showing the relationship between the table pointer T _A3 and the pre-heat pulse width P _1.

[31] (A), (B) and (C) are diagrams showing the relationship between the head temperature T _H and the pre-heat pulse width P _1.

FIGS. 32A and 32B are perspective views illustrating an ink jet cartridge according to another embodiment of the present invention.

FIGS. 33A and 33B show the printed circuit board 8;
FIG. 5 is a diagram for explaining a main circuit configuration on 51.

FIG. 34 is a timing chart for driving the heating element 857 in a time-division manner for each block.

FIGS. 35A and 35B are perspective views for explaining still another example of a recording head.

[Explanation of symbols]

 1,856 Electrothermal transducer (discharge heater) 2 Carriage 3 Ink liquid path 7 Discharge port 9,853 Heater board (Si substrate) 11 Aluminum plate 20A, 20B Temperature sensor 30A, 30B Temperature control heater 801 CPU 803 ROM 805 RAM

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Jin Sugimoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Miyuki Matsubara 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inside (72) Inventor Yoshiaki Takayanagi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Sohei 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. ( 58) Fields surveyed (Int.Cl. ⁷ , DB name) B41J 2/05 B41J 2/125

Claims (36)

(57) [Claims] 1. Thermal energy is generated by applying a driving signal.
Using a recording head having a heat generating element for generating an ink jet recording method for serial <br/> recording by ejecting ink from the recording head by the heat energy, the driving signal, thermal energy without ejecting ink To
A pulse P ₁ to generate, Pal after pulse P ₁
And ejecting the ink to be applied at a scan pause interval P ₂
The signal comprising a plurality of pulses including a pulse P ₃ of the order, according to the temperature of the recording head, the plurality of pulses
Tomo Changing the waveform of the pulse P ₁ to relatively preceding Chi
In the case where the temperature of the recording head is above the predetermined temperature, the ink jet recording method characterized by a constant the pulse P ₁ of the waveform of the drive signal. 2. The method according to claim 1, wherein the temperature of the recording head is higher than a predetermined temperature.
At this time, the driving signal is set to a relatively preceding pulse P ₁
2. The signal according to claim 1, wherein
On-board inkjet recording method. 3. Thermal energy is generated by applying a driving signal.
In an ink jet recording method for performing recording by ejecting ink from the recording head using the thermal energy by using a recording head having a heating element that generates heat, the driving signal is converted to thermal energy without ejecting ink. To
A pulse P ₁ to generate, Pal after pulse P ₁
And ejecting the ink to be applied at a scan pause interval P ₂
The signal comprising a plurality of pulses including a pulse P ₃ of the order, according to the temperature of the recording head, the plurality of pulses
Tomo Changing the waveform of the pulse P ₁ to relatively preceding Chi
, If the temperature is relatively high, when the temperature is relatively low
In comparison, the interval of temperature to change the waveform of the pulse P ₁
An ink jet recording method characterized by being shortened . 4. Thermal energy is generated by applying a drive signal.
Using a recording head having a heating element to generate heat,
The ink is ejected from the recording head by energy to record.
In the ink jet recording method for performing recording, the drive signal is converted into heat energy without discharging ink.
A pulse P ₁ to generate, Pal after pulse P ₁
And ejecting the ink to be applied at a scan pause interval P ₂
The signal comprising a plurality of pulses including a pulse P ₃ of the order, according to the temperature of the recording head, the plurality of pulses
Tomo Changing the waveform of the pulse P ₁ to relatively preceding Chi
, If the temperature is relatively high, when the temperature is relatively low
Of the pulse P ₁ with respect to the temperature change amount
Ink cartridge characterized by increasing the amount of shape change
Jet recording method. 5. Thermal energy is generated by applying a driving signal.
Using a recording head having a heating element to generate heat,
The ink is ejected from the recording head by energy to record.
In the ink jet recording method for performing recording, the drive signal is converted into heat energy without discharging ink.
A pulse P ₁ to generate, Pal after pulse P ₁
And ejecting the ink to be applied at a scan pause interval P ₂
The signal comprising a plurality of pulses including a pulse P ₃ of fit, when said temperature of the recording head is lower than a predetermined first temperature, the discharge amount by the temperature control of at least including heating of the recording head the recording head controls, second temperature is predetermined at the first temperature or more of said recording head
When lower temperatures are relatively preceding one of the plurality of pulses of said plurality driving signal according to the temperature pulse P
_1. The inkjet recording method according to claim ₁ , wherein the waveform of the pulse P1 is changed and the waveform of the pulse P1 is kept constant when the temperature of the recording head is equal to or higher than the second temperature. 6. Change the pulse P ₁ of the waveform, the temperature
If the temperature is relatively high, the temperature is relatively low.
Base, shorter interval of temperature to change the waveform of the pulse P ₁
Inkjet <br/> recording method according to claim 5, characterized in that the. 7. Change the pulse P ₁ of the waveform, the temperature
If the temperature is relatively high, the temperature is relatively low.
Base, the pulse P ₁ of the waveform corresponding to the change in the temperature
6. The ink jet recording method according to claim 5 , wherein the amount to be changed is increased . 8. Changes of the pulse P ₁ of the waveform, the inkjet recording method according to any one of claims 1 to 7, characterized in that by changing the pulse width. 9. The recording head according to claim 1, wherein the thermal energy generated by the heating element causes film boiling in the ink, and discharges the ink with the growth of bubbles due to the film boiling. through according to any one of the 8
Ink jet recording method. 10. Thermal energy by applying a drive signal
And a heat generating element for generating heat.
In an ink jet recording apparatus that performs recording by discharging ink using a recording head that discharges ink, it is necessary to generate thermal energy without discharging ink.
A pulse _{P 1,} the pulse pause interval _{P 2} after the pulse _{P 1}
The pulse P ₃ for discharging ink to be applied apart
Drive signal comprising a plurality of pulses including
Feeding to a head driving means for driving the recording head, a temperature detecting means for detecting the temperature of the recording head, in accordance with the temperature of the recording head, the path of the driving signal
A driving signal modulating means for changing the waveform of the pulse P _1, the when the temperature of the recording head is above the predetermined temperature, the driving
Constant the pulse P ₁ having a waveform relatively preceding motion signal
An ink jet recording apparatus, characterized in that it comprises a modulation control means to. 11. The recording head according to claim 11 , wherein:
When the temperature is equal to or higher than a predetermined temperature, the drive signal is
That the foregoing of the signal without applying the pulse P ₁ to
The ink jet recording apparatus according to claim 10, wherein
Place. 12. The recording apparatus according to claim 12, wherein
If the temperature of the pad is relatively high,
Compared to case, the interval of temperature to change the waveform of the pulse P ₁
The inkjet recording apparatus according to claim 10 , wherein the distance is shortened . 13. The recording device according to claim 1, wherein
If the temperature of the pad is relatively high,
In comparison with the case, the pulse P ₁ with respect to the temperature change amount
The amount of changing the waveform is increased.
An ink jet recording apparatus according to claim 10 . 14. Thermal energy by applying a drive signal.
Having a heating element that generates
The heating element is driven by a driving signal given from the recording apparatus.
An ink jet recording head for performing recording by ejecting ink by the thermal energy generated by the thermal energy generating means for generating thermal energy without ejecting the ink.
A pulse _{P 1,} the pulse pause interval _{P 2} after the pulse _{P 1}
The pulse P ₃ for discharging ink to be applied apart
Out of the drive signals consisting of a plurality of pulses including
Attached to the pulse P ₁ and is subject to change depending on the temperature of the head
Te, to store the information of the pulse P ₁ corresponding to a predetermined temperature
Inkjet, characterized in that it comprises a that information storage means
Doo recording head. 15. The information stored in said information storage means, said information corresponding to a case where a recording head is at a predetermined temperature.
An ink jet recording head according to claim 14, characterized in that the information about the pulse width of the pulse P _1. 16. The information storage unit, an ink jet recording head according to claim 14 or 15, characterized in that a non-volatile memory. 17. The pulse P constituting the drive signal
_1, an ink jet recording head according to claim 14, characterized in that a pulse for adjusting the temperature of the head. 18. The pulse P _3, the heating element emitting
Bubbles for ejecting ink with generated thermal energy
15. The ink jet recording head according to claim 14 , wherein the pulse is a pulse for generating in the ink . 19. The heating element according to claim 1, further comprising :
Inkuji of claim 14 or 15, characterized in this <br/> and a electro-thermal transducer for generating thermal energy Ri
Jet recording head. 20. Thermal energy by applying a drive signal
And a heat generating element for generating heat.
Using a printhead that discharges ink
In an ink jet recording apparatus that performs recording by means of
A pulse _{P 1,} the pulse pause interval _{P 2} after the pulse P ₁
The pulse P ₃ for discharging ink to be applied apart
Drive signal comprising a plurality of pulses including
Head driving means for feeding and driving the recording head, and temperature detecting means for detecting the temperature of the recording head
The drive signal according to the temperature of the recording head.
Driving signal modulating means for changing the waveform of the pulse P ₁
When have the driving signal modulating means, the pulse P corresponding to a predetermined temperature from the information storage means for the recording head having
Get information _first width, the ink jet recording apparatus characterized by changing the width of the pulse P ₁ to be supplied to the heating elements of the recording head. 21. The information , wherein the temperature of the recording head is
A <br/> information related to the pulse P ₁ having a width corresponding to the case of the predetermined temperature, the driving signal modulating means based on the information
Te, In of claim 20, wherein determining said <br/> width of the pulse P ₁ corresponding to the temperature of said recording head
Jet recording device. 22. The driving signal modulating means reads the information corresponding to the width of the pulse P ₁ determined for each temperature range of the recording head from the recording head, it is detected
The pulse P ₁ having a width which corresponds to the temperature of said recording head
The ink according to claim 20 , wherein the ink is changed to:
Jet recording device. 23. The method of claim, wherein the pulse P ₁ is a signal for adjusting the temperature of said recording head
23. The ink jet recording apparatus according to any one of 20 to 22 . 24. The pulse P ₃ ejects ink
In according to any one of claims 20 to 22, wherein a bubble that a is a signal generated in the ink for
Jet recording device. 25. The heating element is an electrothermal transducer der
Ri, ink jet recording apparatus according to any one of claims 20, characterized in that the thermal energy that is generated by the electrothermal transducer to generate bubbles in ink to eject ink 24. 26. An ink jet recording apparatus according to claim 20 which <br/> stone 25, wherein said information storage means for the recording head is <br/> nonvolatile memory. 27. A heating element for generating heat energy.
Using a recording head,
Inkjet for recording by ejecting ink from the recording head
In the recording method, the driving signal is transmitted from an information storage unit of the recording head.
Reading the information relating to the recording head; detecting the head temperature of the recording head; and a first pulse for increasing the ink temperature in the vicinity of the heater without ejecting the ink that was applied in advance to the ejection of one ink droplet. And changing the width of the first pulse based on the temperature of the recording head by using a drive signal including a second pulse that is applied after a signal pause period after applying the first pulse and ejects ink. And a driving step for performing driving. The driving step includes reading from the recording head.
The temperature of the recording head is determined based on the
Determining the width of the first pulse corresponding to the temperature;
And the inkjet recording method characterized by changing the width of the first pulse. 28. Information read from said information storage means
28. The ink jet recording method according to claim 27 , wherein information corresponding to a case where the temperature of the recording head is a predetermined temperature corresponds to a width of the first pulse . 29. A print head having a heater,
An ink jet that supplies heat energy according to a drive signal applied to the heater to the ink to form bubbles in the ink, and discharges the ink from a recording head onto a recording medium based on the formation of the bubbles to perform recording. in the recording apparatus, the ink droplet 1 ejected, the ink is applied prior to ejection
A first pulse for raising the temperature of the ink near the heater without being output, and a second pulse for discharging the ink after a signal pause period after the application of the first pulse are applied .
A driving means, detecting means for detecting the temperature of the recording head, the temperature of the recording head detected by said detecting means
Depending on, among pulses applied by the driving signal, to change the width of the first pulse applied prior to, and changing means for enabling the ejection amount of ink ejected, which has a range to change the width of the first pulse by said changing means
Even when the width of the first pulse is near the longest,
An ink jet recording apparatus in which at least the signal idle period is characterized by not shorter than a width of the first pulse. 30. A collector of the second pulse and the first pulse
30. The ink of claim 29 , wherein the pressures are equal.
Jet recording device. 31. The width of the first pulse b of claim 29 being shorter than the width of the second pulse <br/>
Liquid jet recording device. 32. A print head having a heater,
Heat energy according to the drive signal applied to the heater
To the ink to form bubbles in the ink,
Ejects ink from the recording head onto the recording medium based on the formation
In an ink jet recording apparatus which performs recording by ejecting ink , the ink applied in advance is ejected with respect to ejection of one ink droplet.
Without increasing the temperature of the ink near the heater.
One pulse and a signal pause after applying the first pulse
And a second pulse for ejecting ink is applied
A driving unit, a generating unit that generates a grayscale signal indicating a grayscale , and a driving unit that is applied by the driving signal in accordance with the grayscale signal.
Of the first pulse applied earlier
Change to allow adjustment of the amount of ink ejected.
Further means, which has a range of changing the width of the first pulse by said changing means
Even when the width of the first pulse is near the longest,
At least the signal pause period is longer than the width of the first pulse.
An ink jet recording apparatus characterized by being not short . 33. A heater for generating heat energy
A recording head using the thermal energy.
An ink jet recording method for performing recording by discharging ink from a head , wherein the step of detecting a temperature of the recording head and the step of detecting a temperature of the recording head without discharging ink applied in advance with respect to one ink droplet discharge. A driving step of applying a first pulse for raising the temperature of the ink near the heater and a second pulse for applying the first pulse to the heater and applying a second pulse for ejecting ink after a signal pause period, and driving the heater. In driving the heater, the amount of the ink to be ejected is adjusted by changing the width of the first pulse in accordance with the temperature of the recording head, and at least the signal pause period is set to The width of the first pulse
Near the longest width of the first pulse in the range to be changed
Jet recording method comprising at also was to not shorter than a width of the first pulse when. 34. Electrodeposition of the second pulse and the first pulse
34. The ink of claim 33 , wherein the pressures are equal.
Jet recording method. 35. The signal width of the first pulse is the second path
34. The ink jet recording method according to claim 33 , wherein the signal width is shorter than the signal width of the loose . 36. A heater for generating heat energy
A recording head using the thermal energy.
In an ink jet recording method in which recording is performed by discharging ink from a head, a step of generating a gradation signal indicating a gradation, and a step of generating an ink droplet 1 without applying ink applied in advance. Driving a heater by applying a first pulse for raising the temperature of ink near the heater to the heater and applying a second pulse for applying ink to the heater at a signal pause after applying the first pulse and discharging ink. And adjusting the amount of the ink to be ejected by changing the width of the first pulse in accordance with the gradation signal in driving the heater . The width of the first pulse
Near the longest width of the first pulse in the range to be changed
Jet recording method comprising at also was to not shorter than a width of the first pulse when.