JPH03247457A - Recording device - Google Patents

Abstract

PURPOSE:To prevent ununiformed temperature rise in each of recording heads and to make steady recording possible by providing driving codition-setting means that determine the driving conditions for each of the recording heads in accordance with positions of the recording heads. CONSTITUTION:Temperature signals outputted from temperature-detecting means 4 are inputted into a control device 9, and the control device 9 controls driving of a heater 5 and a blower 7 based on the above-mentioned signals to keep the temperature in each of the recording heads 3 within an appropriate set range. In the case where four recording heads 3 are installed being arranged sideways, the temperature in the recording heads 3B, 3C installed in the middle is controlled so that it becomes lower by 1 deg.C to 3 deg.C than the temperature of the recording heads 3A, 3D that are positioned on both outer sides of the heads 3B, 3C. The signals outputted from each of the temperature-detecting means 4 are taken into the control device 9 as digital data for the present-time temperature in each of the recording heads 3 through a conversion amplifier 8A and an A/D converter 8. In the case where heating is required because the temperature in the recording heads is low, a driving signal is outputted from the control device 9 through a heater-driving circuit 10, while in the case where cooling is required because of high temperature in the recording heads, a driving signal is outputted to the blower 7.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a recording device such as an inkjet recording device that performs recording by ejecting ink using thermal energy.

[Conventional technology]

2. Description of the Related Art Recording devices such as printers, copying machines, and facsimile machines are configured to record images consisting of dot patterns on recording materials such as paper and thin plastic plates based on image information.

The recording device may be an inkjet type,
It can be divided into wire dot type, thermal type, laser beam type, etc. Among these, inkjet type (inkjet recording device) records on the recording material by ejecting recording liquid (ink) droplets from the ejection opening of the inkjet recording head. It is configured as follows.

The thermal type can be divided into a thermal recording type and a thermal transfer recording type.

In addition, this inkjet recording device can be divided into a method using an electrothermal converter such as a heating element (bubble jet method) and a method using an electromechanical converter such as a piezoelectric element, depending on the ink ejection energy generating body used. .

Among these various recording methods, recording apparatuses having a recording head that performs recording using thermal energy, such as bubble chef recording, thermal recording, and thermal transfer recording, and the inkjet recording apparatus have simple configurations.
Moreover, it has the advantage that it can be easily colored.

In addition, inkjet recording devices, which perform recording by ejecting ink onto a recording material, have advantages such as being a non-impact system, making less noise, and making it easy to record color images using multicolored inks. have.

Therefore, printing apparatuses that perform printing using thermal energy and inkjet printing apparatuses may be equipped with a plurality of printing heads, particularly for the purpose of color printing or speeding up printing.

In this case, in a recording apparatus that uses a plurality of recording heads that perform recording using thermal energy, a temperature control means is provided to keep the temperature of each recording head constant in order to obtain a stable image without recording unevenness.

In addition, inkjet recording devices perform recording by ejecting ink directly from fine ejection ports in the recording head, so special considerations not seen with other types of recording devices are required to maintain a stable image condition. is required.

For example, when using a multi-line printhead or multiple printheads, water in the ejection ports and printheads that are not involved in printing during printing may evaporate, increasing the viscosity of the ink. In order to solve this problem, idle ejection is performed in which ink is ejected outside the recording area.

(Technical Problem to be Solved by the Invention) However, in a conventional recording apparatus having a plurality of recording heads that record using thermal energy, for example, four recording heads such as cyan, magenta, yellow and black are used for full color recording. case,
Since the two recording heads located in the center are surrounded by recording heads on both sides (recording heads that generate heat), normal control methods require highly accurate temperature control to make the temperature uniform. There was a technical problem in that the head temperature could become high.

Furthermore, in conventional inkjet recording apparatuses that use a plurality of recording heads, the conditions for idle ejection are either the same for each recording head or are varied depending on conditions such as ink color.

For this reason, especially when using thermal energy such as a bubble jet recording head, the heat dissipation or heat storage state is different between the recording heads located at both ends and the recording head located at the center, so the increase in viscosity of ink at the ejection section is caused. The extent of this difference varies depending on the position of the print head, and under the conventional dry ejection conditions as described above, there are technical issues such as insufficient recovery operation and increased wasteful consumption of ink depending on the print head. Ta.

The present invention has been made in view of the above-mentioned conventional technical problems, and when a plurality of recording heads that record using thermal energy are used, the temperature rise occurs due to differences in heat radiation or heat storage depending on the position of each recording head. Non-uniformity can be prevented,
An object of the present invention is to provide a recording device that can perform stable recording.

Another aspect of the present invention is to reduce the temperature rise caused by the difference in heat radiation or heat accumulation depending on the position of each print head by changing the driving conditions for idle ejection of each print head in an inkjet printing apparatus using a plurality of print heads. It is an object of the present invention to provide a recording device that can prevent non-uniformity and perform stable recording.

[Means for solving problems]

The present invention provides, in a recording apparatus having a plurality of recording heads that perform recording on a recording material using thermal energy, a configuration that includes a drive condition setting means for determining recording head drive conditions based on the position of the recording head. It is an object of the present invention to provide a recording apparatus that can prevent non-uniformity in temperature rise of a recording head and perform stable recording.

In the above configuration, it is preferable to control the temperature so that the temperature of the middle print head among the plurality of print heads is lower than the temperature of the print heads on both sides.

Further, the present invention provides an inkjet recording apparatus having a plurality of recording heads that perform recording by discharging ink onto a recording material, which includes a dummy discharge condition setting means for determining a dummy discharge condition based on the position of the recording head. By doing so, it is possible to eliminate excess or deficiency of idle ejection from each recording head, prevent wasteful consumption of ink, and provide an inkjet recording apparatus that can perform efficient idle ejection with high reliability.

〔Example〕

Hereinafter, the present invention will be specifically described with reference to the drawings.

In addition, below, the case where this invention is applicable to the inkjet recording device of a bubble jet type is mentioned as an example, and is demonstrated.

(Embodiment 1) FIG. 1 is a perspective view showing a main part configuration of an embodiment of a recording apparatus according to the present invention.

In FIG. 1, reference numeral 1 denotes a recording unit mounted on a carriage 2, and the recording unit 1 has a plurality of (in the illustrated example, four) bubble jet recording heads 3 that perform recording using thermal energy. ing.

Each recording head 3 is configured to apply a pulse voltage according to recording information to an electrothermal transducer such as a heating element, and generate bubbles using thermal energy generated from the electrothermal transducer to eject ink. has been done.

That is, each recording head 3 is an inkjet recording head that discharges ink using thermal energy, and is equipped with an electrothermal converter for generating thermal energy.

Each of the inkjet recording heads 3 performs recording by ejecting ink from its ejection openings by the growth of bubbles due to film boiling caused by thermal energy applied by the electrothermal converter.

FIG. 2 is an enlarged perspective view of the recording unit 1, in which each recording head 3 is provided with a temperature detection means 4 and a heater 5.

In this embodiment, the recording unit 7 1 consists of four recording heads 3A, 3B, and 3C13D, each of which can correspond to, for example, yellow, magenta, cyan, and black.

As the temperature detection means 4, a temperature IC, a thermistor, a thermocouple, a varistor, etc. can be used.

Further, as the heater 5, for example, a power transistor or a heating element can be used.

In FIG. 1, 7 is the recording head 3A, 3B, 3C.
, 3D, 13 is a recording material transport motor, and 12 is a transport roller driven by the motor 13 to transport the recording material P in the direction of arrow f. and 14 is the roller 12
The recording material P is held flat in cooperation with the recording unit 1.
This is a roller for forming a recording surface for.

Further, 15 is a carriage drive belt connected to the carriage 2, 16 is a carriage motor for driving the heald 15 in the direction of arrow S, and 18 is a guide shaft for guiding and supporting the carriage 2.

That is, the carriage 2 reciprocates in the direction of arrow S along the guide shaft 18 in accordance with the rotation of the motor 16, and records on the recording surface by driving the recording unit 1 in synchronization with the movement. I can do it.

FIG. 3 is a block diagram illustrating the configuration of a temperature control system that equalizes the temperature of the recording head 3 that performs recording using a plurality of thermal energies of the recording apparatus of FIG. 1.

In FIG. 3, the detection signal of the temperature detection means 4 is input to a control device 9, and the control device 9 controls the driving of the heater 5 and the air blowing means 7 based on this temperature signal, thereby controlling each record. The temperature of the head 3 is controlled to fall within an appropriate set temperature range.

Here, when a plurality (4) of recording heads 3 are mounted side by side as shown in FIGS. 1 and 2, the temperature of the intermediate recording heads 3B and 3C is higher than the temperature of the recording heads 3A and 3D on both sides. The temperature is controlled to be 1°C to 3°C lower.

The output signal of the temperature detection means 4 of each recording head 3 is transmitted to each recording head 3 via a conversion amplifier 8A and an A/D converter 8.
The current temperature of the temperature is taken into the control device 9 as digital data.

On the other hand, the control device 9 issues a drive signal to the heater 5 via the heater drive circuit 10 when the recording head portion is at a low temperature and requires heating, and to the blower means 7 when the recording head portion is at a high temperature and requires cooling.

Figure 4 shows an algorithm for the control operation of the temperature control system in Figure 3. In the figure, T, , T, and T are the upper limit value and lower limit value of the center value temperature, respectively, of the set temperature range. be.

As is clear from Figure 4, when the head temperature changes from low to high temperature, and when it changes from high temperature to low temperature,
Hysteresis is provided by changing the on/off set temperatures of the heater 5 and the blower means 7.

This is because it is difficult to control the center temperature of the recording head 3 so that it is always T2, so an upper limit 4rLTl and a lower limit T3 are set according to the set temperature range, and the head temperature is set within that set temperature range. This is to control.

When using a plurality of recording heads 3 (for example, three or more), during recording, the recording heads 3B and 3C located in the middle store heat and rise in temperature more easily than the recording heads 3A and 3D on both sides.
In the above temperature control system, the set temperature of the middle recording heads 3B and 3C is 1 higher than the set temperature of the recording heads 3A and 3D on both sides.
℃~3℃ low (selected.

By changing the set temperature depending on the position of the recording head 3 in this way, it was possible to eliminate non-uniformity in the temperature of each recording head 3 as a result.

Further, in the present invention, by changing the driving conditions of the plurality of recording heads 3 that use thermal energy depending on the position of each of the recording heads 3, the temperature resulting from the difference in heat radiation or heat storage depending on the position of each recording head 3 can be reduced. Provided is a recording device that can prevent non-uniformity and perform stable recording.

FIG. 5 shows a bubble jet inkjet recording head having an ejection orifice density of 400 dpi and 128 ejection orifices, using four recording nodules, and using ink with a dye concentration of 3 evt%. 3 is a graph showing the temperature change of each recording head 3 when recording is performed at a recording ratio of 75% under temperature control control at a set temperature of 35° C. while driving with a pulse width of 30 V and a pulse width of 15 μsec.

As shown in FIG. 5, the recording heads 3A and 3D on both sides have four
It is saturated at 0'C, and the recording heads 3B and 3C at the intermediate position are 4
Saturated at 2°C.

Therefore, by making the head drive pulse width of the intermediate recording heads 3B and 3C small in advance (by making
The temperature increase was controlled to be lower than that in A and 3D.

In order to eliminate non-uniformity in the temperature of each recording head 3, the pulse width at this time must be equal to the pulse width of the heads 3A and 3D on both sides! It was appropriate to set the pulse width of the intermediate heads 3B and 3C to 12 μsec compared to 5 μsec.

Multiple recording nodes using thermal energy (for example,
4) In the installed recording device, it is possible to eliminate temperature non-uniformity caused by differences in heat radiation or heat storage depending on the position of each recording head 3 by changing the head drive voltage of each recording head 3. can.

As mentioned above, in a bubble jet inkjet recording head having an ejection orifice density of 400 dpi and 128 ejection orifices, four recording heads were used, an ink with a dye concentration of 3 wt% was used, and a 30V When recording with a recording ratio of 75% under temperature control control at a set temperature of 35°C with a pulse width of 15 μsec, by suppressing the driving voltage of the intermediate recording heads 3B and 3C from 30V to 28V. By compensating for the difference in saturation temperature as shown in FIG. 5, it was possible to eliminate temperature non-uniformity among the recording heads 3.

Furthermore, as another driving condition setting means for eliminating temperature non-uniformity among the four recording heads 3, there is a means for applying a voltage and/or a pulse width that does not record when not recording, depending on the position of the recording head 3. can also be adopted.

That is, in yet another embodiment, a voltage pulse is applied to the recording heads 3A and 3D on both sides, where the head/nod temperature tends to be low, to the extent that no recording is performed when not recording (ink is not ejected in the case of a bubble jet recording head). By applying , it is possible to raise the temperature to the same level as the middle recording heads 3B and 3C, and by performing such temperature control, it is possible to reduce the temperature caused by differences in heat radiation or heat storage depending on the position of each recording head. A multi-head thermal recording device capable of preventing inconsistencies and performing stable recording has been obtained.

According to each embodiment described above, a plurality of recording heads 3
Depending on the position, the driving conditions, i.e., the driving voltage and/or driving pulse width during recording operation, the voltage and/or pulse width applied during non-recording to the extent that no recording is applied,
By controlling the temperature of each recording head itself during recording operation according to individually set conditions, non-uniformity in temperature caused by differences in heat radiation or heat storage depending on the position of each recording head 3 can be eliminated. Thus, a recording device capable of performing stable recording was obtained.

FIG. 6 is a perspective view schematically showing the configuration of essential parts of an embodiment of an inkjet recording apparatus according to the present invention.

In the following, a case where the present invention is applied to a bubble jet type inkjet recording apparatus will be described as an example.

In FIG. 6, reference numeral 1 denotes a recording unit mounted on a carriage 2, and the recording unit 1 has a plurality of (in the illustrated example, four) bubble jet recording nozzles 3 that perform recording using thermal energy. are doing.

Each of the recording heads 3 is an inkjet recording head that discharges ink using thermal energy, and is equipped with an electrothermal converter for generating thermal energy.

Each of the inkjet recording heads 3 performs recording by ejecting ink from its ejection openings by the growth of bubbles due to film boiling caused by thermal energy applied by the electrothermal converter.

In this embodiment, the recording unit 1 includes four recording heads 3.
It consists of A, 3B, 3C13D, and each can correspond to, for example, yellow, magenta, cyan, and black.

13 is a recording material conveyance motor; 12 is the motor 1;
A transport roller 14 is driven by 3 to transport the recording material P in the direction of arrow f, and 14 cooperates with the roller 12 to hold the recording material P flat to form a recording surface for the recording unit 1. It is a roller for

During recording, the recording material P is conveyed by a predetermined pitch in the direction of arrow f every time recording for one line is completed.

Further, 15 is a carriage drive belt connected to the carriage 2, 16 is a carriage motor for driving the belt 15 in the direction of arrow S, and 18 is a guide shaft for guiding and supporting the carriage 2.

That is, the carriage 2 reciprocates in the direction of arrow S along the guide shaft 18 in accordance with the rotation of the motor 16, and records on the recording surface by driving the recording unit l-1 in synchronization with the movement. be able to.

FIG. 7 is a perspective view schematically showing the arrangement of the plurality of recording heads 3A to 3D mounted on the carriage 2.

In FIGS. 6 and 7, 21 indicates each recording head 3A.
22 is a return pipe that returns ink from each recording head 3A to 3D to an ink tank 23, and 24 is a recovery device for restoring the ejection state of each recording head 3. be.

The recovery device 24 is disposed at a position where the recording head 3 faces the recording head 3 when the carriage 2 comes to the home position H, and performs a recovery operation by discharging or emptying ink from the discharge ports of the recording head 3. will be carried out.

However, the inkjet recording apparatus according to the present invention has a recording head 3 that performs recording by ejecting ink onto the recording material P.
In an inkjet recording apparatus having a plurality of (four in the illustrated example), the position of each recording head 3 (for example,
A dry discharge condition setting means is provided for individually determining the dry discharge condition depending on whether the discharge condition is located on both sides or in the middle.

FIG. 8 is a flowchart showing the sequence of control operations of this idle discharge condition setting means.

In FIG. 8, first, recording is started in step 5101, and in step 5102, the carriage 2 is driven to start a recording scan operation on the recording surface of the recording material P.

Then, in step 5103, it is determined whether a certain period of time has elapsed during recording and it is time to perform dry ejection. When it is determined that the time has come to perform dry ejection, step 5104 determines whether the scan has ended or not. After determining (whether or not the recording of the corresponding line has been completed) and finishing recording of that line, step 5
At step 105, the carriage 7 is returned to the home position H, and at step 5106, a drive pulse for proper idle ejection is applied to each recording head 3.

Here, the appropriate drive pulse is determined by taking into account the temperature rise depending on the position of each recording head 3.

FIG. 4 is a table showing an example of setting the idle ejection conditions according to the positions of the four illustrated recording heads 3A to 3D.

The table in FIG. 4 shows that bubble jet recording heads with a density of 400 dpi and 128 ink ejection ports are used as the recording heads 3A to 3D for each color, and the frequency of all four recording heads 3 is 1.0 KHz. while simultaneously driving the
The saturation temperature is shown when recording is performed at a recording ratio of 25% in an atmosphere of room temperature 25°C.

As seen in the table of FIG. 4, the saturation temperature of the recording head 3 is 30°C for the recording heads 3A and 3D on both sides.
The temperature was 32°C in the intermediate recording heads 3B and 3C.

That is, the saturation temperature of the print heads 3A and 3D located at the ends is the same as that of the print head 3B located in the middle between the other print heads.
, lower than the saturation temperature of 3C.

Therefore, when performing dry ejection with these four print heads at the same time during the recovery operation due to dry ejection, the print heads 3A and 3D on both sides, which have lower temperatures, will
00 pulses of dry ejection is performed to set the applied heating energy to a large amount, and for the middle recording heads 3B and 3C where the temperature is high, 70 pulses of dry ejection are performed for each dry ejection to lower the amount of applied heating energy. When idle ejection driving was performed with the setting set to , it was possible to eliminate non-uniformity in temperature of each of the recording heads 3A to 3D during recording operation.

In another embodiment, a drive voltage and/or pulse width that does not actually eject ink is applied to each print head 3 during each empty ejection, and this drive condition is set to the position of the print head 3. Also by changing the temperature by changing the temperature, it was possible to eliminate non-uniformity in temperature caused by differences in heat radiation or heat storage among the recording heads 3A to 3D.

In other words, internal heating is applied during each discharge,
By changing the amount of internal heating depending on the position of each recording head 3, it was possible to solve the problem of non-uniformity in temperature of each recording head 3A to 3D, as in the case described above.

Furthermore, the same effect as in the above case could be obtained by changing the frequency of blank ejection depending on the position of each of the plurality of recording rads 3.

For example, if the home position I in FIG.
For A and 3D, 50 pulses of idle ejection are performed during each scan, and if the middle recording heads 3B and 3C, which have higher temperatures, are controlled to perform 50 pulses of idle ejection every 2 scans, then the same number of pulses of idle ejection will be Even if there is such a difference, the total thermal energy can be changed, and therefore, as in the case described above, non-uniformity in temperature of each of the recording heads 3A to 3D can be eliminated.

According to each of the embodiments described above, in an inkjet recording apparatus having a plurality of inkjet recording heads 3A to 3D that eject ink using an electrothermal transducer, the idle ejection conditions are determined based on the position of each recording head. Since the dry ejection condition setting means is provided to change the dry ejection conditions in consideration of the temperature rise of each print head, non-uniformity in temperature caused by differences in heat radiation or heat accumulation depending on the position of each print head 3 can be avoided. Thus, an inkjet recording apparatus capable of performing stable recording without recording unevenness etc. was obtained.

In each of the above embodiments, the present invention has been explained by taking as an example a case in which the present invention is applied to a serial type recording apparatus that is mounted on a carriage and moves over a recording material. It was also possible to carry out the same procedure in a recording apparatus using a recording head of 1, and obtain the same effect.

INDUSTRIAL APPLICABILITY The present invention brings about excellent effects particularly in inkjet recording heads of the bubble jet type among inkjet recording systems and inkjet recording apparatuses using the recording heads.

As for typical configurations and principles thereof, it is preferable to use the basic principles disclosed in, for example, US Pat. No. 4,723,129 and US Pat. No. 4,740,796.

This method can be applied to both the so-called on-demand type and the continuous type, but especially in the case of the on-demand type, it is necessary to place the liquid (ink) on the sheet or liquid path where it is held. By applying at least one drive signal that corresponds to recorded information and causes a rapid temperature rise exceeding nucleate boiling to the electrothermal transducer, the electrothermal transducer generates thermal energy, and the recording head This is effective because it causes film boiling on the heat acting surface of the liquid (ink), resulting in the formation of bubbles in the liquid (ink) in one-to-one correspondence with this drive signal.

Due to the growth and contraction of these bubbles, liquid (
ink) to form at least one droplet.

If this drive signal is in the form of a pulse, bubble growth and contraction will occur immediately and appropriately, so liquids with particularly excellent responsiveness (
Ink) can be ejected, which is more preferable. As this pulse-shaped drive signal, those described in US Pat. No. 4,463,359 and US Pat. No. 4,345,262 are suitable.

Further, if the conditions described in US Pat. No. 4,313,124 concerning the temperature increase rate of the heat acting surface are adopted, even more excellent recording can be achieved.

The configuration of the recording head includes, in addition to the combined configuration of ejection ports, liquid paths, and electrothermal converters (straight liquid flow path or right-angled liquid flow path) as disclosed in the above-mentioned specifications, a heat acting section. US Pat. No. 4,558,333 and US Pat. No. 4,459,600 disclose a configuration in which the
The present invention also includes a configuration using the specification of the above specification.

In addition, Japanese Patent Application Laid-open No. 123670 of 1982 discloses a configuration in which a common slit is used as a discharge part for a plurality of electrothermal converters, and a hole that absorbs pressure waves of thermal energy is disclosed. The present invention is also effective as a configuration based on Japanese Patent Application Laid-Open No. 138461 of 1981, which discloses a configuration in which a discharge portion corresponds to a discharge portion.

Furthermore, as a full-line type recording head having a length corresponding to the width of the maximum recording medium that can be recorded by the recording apparatus, the length can be increased by combining multiple recording heads as disclosed in the above-mentioned specification. Either a configuration that satisfies the above requirements or a configuration as a single recording head formed integrally may be used, but the present invention can more effectively exhibit the above-mentioned effects.

In addition, a replaceable chip-type recording head that is attached to the device body enables electrical connection to the device body and ink supply from the device body, or a chip-type recording head that is installed integrally with the recording head itself. The present invention is also effective when a cartridge type recording head is used.

Further, it is preferable to add recovery means, preliminary auxiliary means, etc. for the recording head, which are provided as a configuration of the recording apparatus of the present invention, because the effects of the present invention can be further stabilized.

Specifically, these include capping means, cleaning means, pressure or suction means, preheating means for the recording head using an electrothermal transducer or another heating element, or a combination thereof. It is also effective to perform a preliminary ejection mode in which ejection is performed separately from printing in order to perform stable printing.

Furthermore, the recording mode of the recording device is not limited to only the mainstream color such as black (although the recording head may be configured integrally or by a combination of multiple colors, it may also be possible to record multiple colors of different colors or mixed colors). The present invention is also extremely effective for devices equipped with at least one full color image.

In the embodiments of the present invention described above, the ink is explained as a liquid, but it is an ink that solidifies at room temperature or lower, and is softened or liquid at room temperature, or in the above-mentioned inkjet, the ink itself is heated at 30°C or higher. Since the temperature is generally controlled within a range of 70° C. or less so that the viscosity of the ink is within the stable ejection range, it is sufficient that the ink is in a liquid state when the recording signal is applied.

In addition, it is possible to actively prevent temperature rise due to thermal energy by using it as energy to transform the ink from a solid state to a liquid state, or to prevent ink from evaporating when it is left to solidify. In any case, the ink may be liquefied by applying thermal energy in accordance with the recording signal and ejected as liquid ink, or it may already begin to solidify when it reaches the recording material. It is also applicable to the present invention to use ink that is liquefied only by thermal energy.

In such a case, as in Japanese Patent Application Laid-open No. 54-56847, the ink is held as a liquid or solid in the recesses or through holes of the porous sheet and is placed facing the electrothermal transducer. It may be in any form.

In the present invention, the most effective method for the above-mentioned ink is the one that implements the above-mentioned film boiling method.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, in a recording apparatus having a plurality of recording heads that perform recording on a recording material using thermal energy, drive condition setting that determines recording head driving conditions based on the position of the recording head is provided. Since the configuration includes the means, it is possible to prevent non-uniformity in temperature caused by differences in heat radiation or heat accumulation depending on the position of each recording head, and to provide a recording apparatus that can perform stable recording.

According to another aspect of the present invention, in a recording apparatus having a plurality of recording heads that perform recording on a recording material using thermal energy, the temperature of the intermediate recording head among the plurality of recording heads is lower than the temperature of the recording heads on both sides. Since the configuration has a temperature control means that adjusts the temperature to lower the temperature, it is possible to prevent temperature non-uniformity caused by differences in heat radiation or heat storage depending on the position of each recording head, and a recording device that can perform stable recording is now available. be done.

According to still another aspect of the present invention, in an inkjet recording apparatus having a plurality of recording heads that perform recording by discharging ink onto a recording material, idle ejection condition setting is configured to determine the idle ejection condition based on the position of the recording head. Since the configuration includes the means, it is possible to prevent non-uniformity in temperature caused by differences in heat radiation or heat storage depending on the position of each recording head, and to provide a recording apparatus that can perform stable recording.

[Brief explanation of drawings]

The first part is a schematic perspective view showing the main part configuration of an embodiment of the recording apparatus according to the present invention, FIG. 2 is a schematic perspective view of the recording hand unit shown in FIG. 1, and FIG. A block diagram showing the temperature control system of the recording head of the apparatus, FIG. 4 is the same as that of FIG. 3! FIG. 5 is a graph showing the difference in saturation temperature depending on the position of the print head; FIG. 6 is a schematic diagram showing the main part configuration of an inkjet printing apparatus according to the present invention. 7 is a schematic perspective view showing the recording head unit in FIG. 6, FIG. 8 is a flowchart showing the sequence of the idle ejection operation in the recording apparatus shown in FIG. 6, and FIG. 2 is a table showing temperature differences and idle ejection conditions depending on the position of each print head. Below, symbols representing main components in the drawings are listed. 1.----recording head unit, 2.--11---
Carriage, 3 (3A to 3D) --1-- Recording head, 4-- Temperature detection means, 5...
. . . heater, 7 . . . 1-- cooling means (blow fan), 9 . P--Recording material, S--Carriage movement direction (scanning direction)
, r--- Recording material conveyance direction. Figure 4 Figure 8 Figure 9

Claims (12)

[Claims] (1) A recording apparatus having a plurality of recording heads that perform recording on a recording material using thermal energy, characterized in that the recording apparatus has a driving condition setting means for determining recording head driving conditions based on the position of the recording head. (2) The printing apparatus according to claim 1, wherein the drive condition setting means is a means for determining a drive voltage and/or a drive pulse width of the printhead based on the position of the printhead. (3) The driving condition setting means is a means for applying a voltage and/or a pulse width that does not cause recording during non-recording depending on the position of the recording head.
The recording device described in . (4) Claim 1 characterized in that it has a temperature control means that adjusts the temperature so that the temperature of the middle recording head among the plurality of recording heads is 1° C. to 3° C. lower than the temperature of the recording heads on both sides. The recording device described in . (5) A claim characterized in that the recording head is an inkjet recording head that ejects ink using thermal energy and is equipped with an electrothermal converter for generating thermal energy. The recording device according to item 1. (6) The recording apparatus according to claim 5, wherein the ink is ejected from the ejection port by the growth of bubbles due to film boiling caused by the thermal energy applied by the electrothermal converter. (7) An inkjet recording apparatus having a plurality of recording heads for performing recording by discharging ink onto a recording material, characterized in that the inkjet recording apparatus includes a blank discharge condition setting means for determining a blank discharge condition based on the position of the recording head. Inkjet recording device. (8) The inkjet recording apparatus according to claim 7, wherein the idle ejection condition setting means is a means for determining the number of idle ejection pulses based on the position of the recording head. (9) The inkjet recording apparatus according to claim 7, wherein the idle ejection condition setting means is a means for determining the number of scans between idle ejections based on the position of the recording head. (10) The dry ejection condition setting means is a means for determining a drive voltage and/or a drive pulse width for dry ejection based on the position of the recording head.
The inkjet recording device described in . (11) A claim characterized in that the recording head is an inkjet recording head that ejects ink using thermal energy and is equipped with an electrothermal converter for generating thermal energy. Item 7. The inkjet recording device according to item 7. (12) Ink is ejected from the ejection port by the growth of bubbles due to film boiling caused by the thermal energy applied by the electrothermal converter.
1. The inkjet recording device according to 1.