JP2001105613A - Ink jet recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording apparatus capable of performing a flashing operation by an optimized drive signal and capable of efficiently discharging unnecessary ink such as thickened ink or the like. SOLUTION: A piezoelectric vibrator 6 is contracted and extended by sending a drive signal COM from a printer controller 19 to the electric drive system of a recording head. Since the piezoelectric vibrator 6 displaces the surface of the vibration plate of a pressure chamber allowing ink to flow in the recording head, ink drops are ejected from nozzle orifices to print (record) an image or character on recording paper. When a flashing command is issued in a control part 194, a predetermined parameter is sent to a drive signal forming circuit 8 to form a first drive signal with a waveform capable of suppressing the lead-in of the meniscus of each nozzle orifice and a second drive signal with a waveform and a repeating cycle at a time of usual printing and these signals are successively sent to the electric drive system 44 to perform two-stage drive control.

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 apparatus for recording an image, a character or the like on a recording medium by a recording head which discharges ink droplets from nozzle openings, and in particular, a flushing operation for forcibly discharging ink droplets. About what to do.

[0002]

2. Description of the Related Art An ink jet printer, which is a typical ink jet recording apparatus, is already well known. This ink jet printer includes an ink jet type recording head that discharges ink droplets from nozzle openings, and is configured to record images, characters, and the like by landing ink droplets on a recording medium such as recording paper. .

The recording head is supported by a carriage with the nozzle surface having the nozzle openings formed facing the recording paper, and moves (main scan) in the width direction of the recording paper along a guide member. The ink droplets are ejected in synchronization with the main scanning.

In the above-described ink jet printer, a flushing operation for discharging ink droplets is performed regardless of a recording operation. For example, when the thickened or solidified ink is discharged out of the recording head near the nozzle opening, after the nozzle surface is wiped by the cleaning mechanism, or when the nozzle surface is sealed by the capping mechanism, the ink inside the recording head is sealed. Flushing operation is performed after forcibly sucking out.

In this flushing operation, for example, the recording head is moved to a position of the capping mechanism outside the recording range, and a flushing drive signal is supplied to the recording head.
This prevents the deterioration of the image quality due to the thickened ink and the solidified ink, and prevents the color mixture of the ink after the wiping by the cleaning mechanism or the suction of the ink.

[0006]

However, it has been found that in the above-mentioned conventional apparatus, a large amount of ink is required to sufficiently discharge the thickened ink and the solidified ink out of the recording head.

This is because the flushing drive signal is generated with the same waveform as the recording drive signal. That is, the flushing drive signal includes a drive pulse that rapidly expands and then contracts the pressure chamber rapidly, like the recording drive signal, and continuously supplies this drive pulse in a short repetition cycle. .

Therefore, when such a flushing drive signal is supplied in a state where the ink near the nozzle opening has thickened or solidified, rapid expansion and contraction of the pressure chamber are continuously performed. As a result, there is a possibility that the thickened ink or the like is diffused into the pressure chamber. When the thickened ink or the like is diffused, it is difficult to sufficiently discharge the thickened ink or the like diffused into the pressure chamber unless a large amount of ink is ejected.

The present invention has been made in view of such circumstances, and can reliably discharge unnecessary ink such as thickened ink and solidified ink, and can shorten the flushing operation time. An object of the present invention is to provide an ink jet recording apparatus.

[0010]

SUMMARY OF THE INVENTION The present invention has been proposed to achieve the above object. According to the first aspect of the present invention, a pressure in a pressure chamber communicating with a nozzle opening is changed according to a drive signal. A recording head that discharges ink droplets from nozzle openings by this pressure fluctuation, and a drive signal generating unit that can generate a flushing drive signal. In the ink jet recording apparatus for performing a flushing operation for forcibly discharging the recording medium, the drive signal generation means generates a series of flushing drive signals including a first drive signal and a second drive signal. This is an ink jet recording apparatus.

According to a second aspect of the present invention, the first drive signal includes a first filling element that fills the pressure chamber with ink while suppressing the meniscus from being drawn into the pressure chamber, and the first filling element supplies the ink with the first filling element. A first discharge element including a first discharge element for rapidly contracting the filled pressure chamber to discharge an ink droplet;
2. The ink jet recording apparatus according to claim 1, further comprising a flushing pulse, wherein the plurality of first flushing pulses are connected in series.

According to a third aspect of the present invention, the second drive signal includes a second filling element for rapidly expanding the pressure chamber and filling the pressure chamber with ink, and the second filling element is filled with ink. A plurality of second flushing pulses including a second ejection element for ejecting ink droplets by rapidly contracting the pressure chamber are provided, and the second flushing pulses adjacent to each other are connected in series so as to be close to each other. An ink jet recording apparatus according to claim 2.

According to a fourth aspect of the present invention, the ejection amount of the ink droplet by the first flushing pulse is set to be larger than the ejection amount of the ink droplet by the second flushing pulse. This is an ink jet recording apparatus.

According to a fifth aspect of the present invention, there is provided the ink jet type recording apparatus according to the third or fourth aspect, wherein the waveform of the second flushing pulse has the same shape as a print pulse. .

According to a sixth aspect of the present invention, the first drive signal includes a third filling element for rapidly inflating the pressure chamber to fill the pressure chamber with ink, and the third filling element filling the ink. A plurality of third flushing pulses including a third ejection element for ejecting ink droplets by rapidly contracting the pressure chamber are provided, and after the pressure fluctuation in the pressure chamber caused by the previous third flushing pulse converges, the next third flushing pulse is generated. 2. The ink jet recording apparatus according to claim 1, wherein the third flushing pulses adjacent to each other are connected in series so as to be supplied so as to be supplied.

According to a seventh aspect of the present invention, the second drive signal includes a fourth filling element for rapidly expanding the pressure chamber and filling the pressure chamber with ink, and the fourth filling element is filled with ink. A plurality of fourth flushing pulses including a fourth ejection element for ejecting ink droplets by rapidly contracting the pressure chamber are provided, and the fourth flushing pulses adjacent to each other are connected in series and brought close to each other. An ink jet recording apparatus according to claim 6, wherein

According to another aspect of the present invention, the waveform of the third flushing pulse and the waveform of the fourth flushing pulse have the same shape. Device.

According to a ninth aspect of the present invention, there is provided the ink jet recording apparatus according to the seventh aspect, wherein the drive voltage of the third flushing pulse is set higher than the drive voltage of the fourth flushing pulse. .

According to a tenth aspect of the present invention, the waveform of at least one of the third flushing pulse and the fourth flushing pulse has the same shape as a print pulse. An ink jet recording apparatus according to any one of claims 9 to 13.

According to the eleventh aspect of the present invention, the third
The ink jet recording apparatus according to any one of claims 6 to 10, wherein an interval between the flushing pulses is set short enough to be arranged on the rear side of the drive signal.

According to a twelfth aspect of the present invention, when the ink in the pressure chamber is active, such as at the end of printing or after a cleaning operation, the driving signal generating means generates a flushing driving signal consisting of only the second driving signal. The ink jet recording apparatus according to any one of claims 1 to 11, wherein:

Here, "activity" means a state in which the ink is in a normal state without any trouble due to an increase in ink viscosity.

According to a thirteenth aspect of the present invention, the drive signal generating means includes output voltage information holding means for holding output voltage information for defining a shape of the drive signal, and change amount information for holding change amount information. Holding means, and adding means for adding the output voltage information and the change amount information to obtain additional voltage information, and switching the change amount information output from the change amount information holding means to the adding means, while updating the update timing. The drive signal of an arbitrary shape is generated by causing the output voltage information holding unit to hold the added voltage information as new output voltage information each time the signal arrives, thereby generating a drive signal of an arbitrary shape. This is an ink jet recording apparatus.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the ink jet recording apparatus of the present invention will be described below with reference to the accompanying drawings. 1 to 7 show a first embodiment of an ink jet recording apparatus according to the present invention, FIG. 1 is a perspective view of a printer which is a typical ink jet recording apparatus, and FIG. 2 shows a recording head. FIG. 3 is a block diagram showing a configuration of a control system, FIG. 4 is a block diagram showing a configuration of a drive signal generation circuit, and FIG. 5 shows a process of generating a waveform serving as a drive signal in the drive signal generation circuit. FIG. 6 is a timing chart showing a drive signal in the flushing operation,
FIG. 7 is an enlarged time chart of the first drive signal of FIG.

In the ink jet printer 1, a carriage 2 is movably mounted on a guide member 11, and the carriage 2 is connected to a timing belt 14 extending between a driving pulley 12 and an idle pulley 13. ing. The driving pulley 12 is joined to a rotation shaft of a pulse motor 15, and the carriage 2 is moved (main scanning) in the width direction of the recording paper 3 by driving the pulse motor 15.

A recording head 4 is mounted on a surface (lower surface) of the carriage 2 facing the recording paper 3. The recording head 4 discharges the ink supplied from the ink cartridge 5 as ink droplets from the nozzle openings 51 (see FIG. 2).

Accordingly, at the time of recording, the printer 1 ejects ink droplets from the recording head 4 in synchronization with the main scanning of the carriage 2, rotates the platen 16 in conjunction with the reciprocation of the carriage 2, and prints the recording paper 3. Move (sub-scan) in the paper feed direction. As a result, images, characters, and the like based on the print data are recorded on the recording paper 3.

A home position is set within the moving range of the carriage 2 and outside the recording area. At this home position, a cleaning mechanism 17 for cleaning the recording head 4 and a capping mechanism 18 for capping are provided side by side. ing. In addition, a printer controller 19 is provided on the rear side of the housing to control the operation of each unit constituting the printer 1 in an integrated manner.

The cleaning mechanism 17 includes a wiper blade 170 formed by laminating a rubber plate and a plate-like felt, a wiper holder 171 for holding the wiper blade 170, and a wiper elevating device for vertically moving the wiper holder 171. And a mechanism (not shown). Then, the nozzle plate 5 of the recording head 4
The cleaning of 0 is performed by pressing the wiper blade 170 against the nozzle plate 50 and then slightly moving the recording head 4 right and left to wipe the surface of the nozzle plate 50.

The capping mechanism 18 includes a tray-like cap member 180 having an open top, and a cap member 1.
A cap lifting mechanism (not shown) for vertically moving the cap 80, a suction tube communicating with the cup-shaped portion of the cap member 180, and a suction pump provided in the middle of the suction tube are provided. Not shown).

The cap member 180 is a member formed by molding an elastic member such as rubber into a substantially square tray shape, and has a moisturizing material such as felt attached inside. When the carriage 2 is located at the home position, the cap member 180 is moved upward by the cap elevating mechanism and pressed against the nozzle plate 50 in conjunction with the movement of the carriage 2. In this pressed state, the nozzle opening 51 is located in the opening region of the cap member 180 and is sealed. When the suction pump operates in this pressure contact state, the internal space of the cap member 180 becomes negative pressure, and ink is forcibly sucked from the recording head 4.

When a flushing drive signal (described later) is supplied to the recording head 4 in a state where the cap member 180 is pressed, the recording head 4 discharges ink droplets into the internal space of the cap member 180. This operation of forcibly discharging the ink droplets is called a flushing operation. For example, the thickening ink or the solidified ink near the nozzle opening 51 generated due to the evaporation of the ink solvent is discharged in advance, or the wiper blade 17 is used.
This is performed to prevent color mixing of ink after wiping with 0 or after forcible suction of ink, or to keep the inside of the cap member 180 moist.

As shown in FIG. 2, the recording head 4 is formed by joining a flow path unit 7 to a tip end surface of a base 40.
Then, the ink in the pressure chamber 71 is pressurized by the piezoelectric vibrator 6 housed in the base 40, and the ink droplet is ejected from the nozzle opening 51 formed in the nozzle plate 50.

The base 40 has a box shape in which a housing chamber 43 for housing the vibrator unit 46 is formed, and is made of, for example, a resin material. The storage chamber 43 extends from the opening on the side of the joint surface with the flow path unit 7 to the opposite surface.

The flow channel unit 7 has a configuration in which the nozzle plate 50 is bonded to one surface of the flow channel forming plate 55 and the vibration plate 60 is bonded to the other surface of the flow channel forming plate 55.

The flow path forming plate 55 is formed of a silicon wafer or the like, and is divided into a predetermined pattern by etching the silicon wafer or the like. The plurality of pressure chambers 71 communicating with the nozzle openings 51 and the common ink chamber A partition wall forming a plurality of ink supply paths 73 and the like from the common ink chamber 72 to each pressure chamber 71 is appropriately formed. The common ink chamber 72 is provided with a connection port connected to the ink supply pipe 48, and the ink stored in the ink cartridge 5 is supplied to the common ink chamber 72 through this connection port.

In the nozzle plate 50, a plurality of nozzle openings 51 are formed in rows at a pitch corresponding to the dot formation density.

The diaphragm 60 is made of a stainless steel plate 61 with PPS.
It has a double structure in which elastic films 62 such as films are stacked, and a portion corresponding to each pressure chamber 71 is formed by etching a stainless steel plate in a ring shape, and an island portion 70 is formed in the ring.

The vibrator unit 46 includes the piezoelectric vibrator 6 (a type of pressure generating element) and the fixed substrate 42. The piezoelectric vibrator 6 is formed in a comb-teeth shape by forming slit portions at a predetermined pitch corresponding to each of the pressure chambers 71 on a single piezoelectric vibrator plate in which piezoelectric bodies and electrode layers are alternately laminated. You. The fixed substrate 42 is provided with the comb-shaped vibrator 6.
Is fixed to the base end portion of

The vibrator unit 46 includes the piezoelectric vibrator 6
Of the base 40 in a posture in which the tip of
The fixed substrate 42 is housed by being fixed to the inner wall of the housing chamber 43. In this housed state, each end of the piezoelectric vibrator 6 comes into contact with the corresponding island 70 of the diaphragm 60.

Each of the piezoelectric vibrators 6 expands and contracts in the element longitudinal direction orthogonal to the laminating direction by applying a potential difference between the opposing electrodes, and displaces the elastic film 62 defining the pressure chamber 71. That is, in the recording head 4, by extending the piezoelectric vibrator 6 in the element longitudinal direction, the island portion 7 is formed.
0 is pushed toward the nozzle plate 50 and the island 70
The peripheral elastic film 62 is deformed, and the volume of the pressure chamber 71 is reduced. When the piezoelectric vibrator 6 is contracted in the element longitudinal direction, the displacement of the elastic film 62 increases the volume of the pressure chamber 71. As the pressure chamber 71 expands or contracts, the pressure chamber 71
Fluctuation in pressure occurs in the ink filled in the inside, and ink droplets are ejected from the nozzle openings 51 of the flow path unit 7.

Next, the electrical configuration of the printer 1 will be described. As shown in FIG. 3, the printer 1 has an external interface 191 and a RAM for temporarily storing various data.
192, a ROM 193 storing a control program and the like,
A control unit 194 including a CPU and the like; an oscillation circuit 195 for generating a clock signal; a drive signal generation circuit 8 for generating a drive signal COM to be supplied to the recording head 4 and functioning as a drive signal generation unit of the present invention; An internal interface 196 for supplying various signals such as dot pattern data (bitmap data) developed based on signals and print data to a drive system side such as the recording head 4 is provided.

The external interface 191 receives print data such as character codes, graphic functions, and image data from a host computer (not shown). Further, a busy signal (BUSY) and an acknowledge signal (ACK) are transmitted through the external interface 191.
Is sent to a host computer or the like.

The RAM 192 is a work memory, and includes a reception buffer RB, an intermediate buffer MB, and an output buffer OB.
Function as etc. That is, the reception buffer RB temporarily stores the print data received via the external interface 191, the intermediate buffer MB stores the intermediate code data converted by the control unit 194, and the output buffer OB stores the dot pattern data. . The dot pattern data is print data obtained by decoding gradation data.

The ROM 193 stores font data, graphic functions, and the like in addition to a control program (control routine) for performing various data processing.

The control unit 194 performs various controls based on a control program read from the ROM 193, reads out print data in the reception buffer RB, and converts intermediate code data obtained by converting the print data into an intermediate buffer. Store in MB. Further, the intermediate code data read from the intermediate buffer MB is analyzed, developed into dot pattern data with reference to font data and graphic functions stored in the ROM 193, and after performing necessary decoration processing, this dot pattern data is Output buffer O
Store it in B.

When one line of dot pattern data that can be printed is obtained by one main scan of the print head 4, this one line of dot pattern data is output from the output buffer OB through the internal interface 196. The data is sequentially output to the recording head 4. When one line of dot pattern data is output from the output buffer OB, the expanded intermediate code data is deleted from the intermediate buffer MB, and the expansion processing for the next intermediate code data is performed.

The electric drive system 44 of the recording head 4 includes a shift register 94 (94A to 94N) and a latch circuit 95 (9
5A to 95N), a level shifter 96 which is a voltage amplifier
(96A-96N), switch 97 (97A-97
N), and the piezoelectric vibrators 6 (6A to 6N) are connected in order, and these are provided for each of the nozzle openings 51.

The operation of ejecting ink droplets by the recording head 4 is controlled by the control unit 194. In the ejection control, first, print data (SI) is serially transmitted from the output buffer OB in synchronization with the clock signal (CK) of the oscillation circuit 195, and the shift register elements 94A to 94N are sequentially transmitted.
To set. If the print data has been set in the shift register elements 94A to 94N for all the nozzle openings 51...
The latch signal (LAT) is output to 5N, and the print data set in the shift register elements 94A to 94N is latched by the latch elements 95A to 95N.

The latched print data is supplied to the level shifter elements 96A to 96N. Each of the level shifter elements 96A to 96N is configured to boost the print data to a voltage value at which the switches 97A to 97N can be driven, for example, several tens of volts, when the print data is, for example, "1". The print data whose pressure has been increased
7A-97N, which causes switches 97A-97N
97N is connected by the print data. When the print data is, for example, "0", the corresponding level shifter elements 96A to 96N do not perform boosting.

A drive signal COM from the drive signal generation circuit 8 is applied to each of the switches 97A to 97N. When the switches 97A to 97N are connected, the piezoelectric vibrators 6A to 6C connected to the switches 97A to 97N are connected. The drive signal COM is supplied to 6N.

The drive signal generation circuit 8 functions as the drive signal generation means of the present invention. The drive signal generation circuit 8 generates a drive signal for recording when printing a character or an image, and generates the drive signal for printing when performing a flushing operation. Generate a flushing drive signal.

As shown in the block diagram of FIG. 4, the drive signal generation circuit 8 is roughly composed of a waveform generation circuit 80 and a current amplification circuit 89.

The waveform generation circuit 80 includes a waveform memory 81,
A first waveform latch circuit 82 and a second waveform latch circuit 84
, An adder 83 and a digital / analog converter 86 (D /
A converter 86) and a voltage amplifying circuit 88.

The waveform memory 81 functions as change amount information storage means for individually storing a plurality of types of voltage change amount data (change amount information) output from the control unit 49 in association with addresses. This waveform memory 81 has a first waveform latch circuit 82 functioning as a change amount information holding means of the present invention.
Are electrically connected. This first waveform latch circuit 8
2 holds the data of the voltage change amount stored at a predetermined address of the waveform memory 81 in synchronization with the first timing signal. The adder 83 functions as the adding means of the present invention. The output of the first waveform latch circuit 82 and the second
The output of the waveform latch circuit 84 is input, and the second waveform latch circuit 84 is electrically connected to the output side of the adder 83. Then, the adder 83 adds the output signals to each other to obtain added voltage information.

The second waveform latch circuit 84 functions as the output voltage information holding means of the present invention, and the data (added voltage information) acquired by the adder 83 in synchronization with the second timing signal.
Is held as output voltage information for defining the shape of the drive signal COM. The D / A converter 86 is electrically connected to the output side of the second waveform latch circuit 84, and converts the data held by the second waveform latch circuit 84 into an analog signal. The voltage amplifying circuit 88 is electrically connected to the output side of the D / A converter 86, and amplifies the analog signal converted by the D / A converter 86 up to the voltage of the drive signal.

The current amplifying circuit 89 is electrically connected to the output side of the voltage amplifying circuit 88. The current amplifying circuit 89 amplifies the current of the signal whose voltage has been amplified by the voltage amplifying circuit 88 and outputs the amplified signal as a drive signal COM.

In the drive signal generation circuit 8 having the above-described configuration, a plurality of change amount data indicating the voltage change amounts are individually stored in the storage area of the waveform memory 81 prior to the generation of the drive signal. For example, the control unit 194 outputs change amount data and address data corresponding to the change amount data to the waveform memory 81. Then, the waveform memory 81 stores the change amount data in a storage area specified by the address data. In this embodiment, the change amount data is composed of data including positive / negative information (increase / decrease information), and the address data is composed of a 4-bit address signal.

When a plurality of types of change amount data are stored in the waveform memory 81 in this manner, a drive signal can be generated.

The driving signal is generated by the first waveform latch circuit 8
2 while switching the change amount data output from the adder 83 to the adder 83 each time a predetermined update timing arrives.
Is performed by causing the second waveform latch circuit 84 to hold the acquired data as new output voltage information, thereby generating a drive signal of an arbitrary shape.

In this embodiment, the first waveform latch circuit 82
The set of the change amount data to the first waveform latch circuit 8 and the 4-bit address signal input to the waveform memory 81 are stored.
2 and the first timing signal input to the second timing signal. That is, the waveform memory 81 selects target change amount data based on the address signal. Then, when the first timing signal is input, the first waveform latch circuit 82 reads out the selected change amount data from the waveform memory 81 and holds it.

The change amount data held in the first waveform latch circuit 82 is input to the adder 83. Since the output voltage information held by the second waveform latch circuit 84 is also input to the adder 83, the output data from the adder 83 includes the change amount data held by the first waveform latch circuit 82 and the output data. It becomes a voltage value obtained by adding the output voltage information held by the two-waveform latch circuit 84. Here, since the change amount data includes positive and negative information, when the change amount data has a positive value, the output data from the adder 83 has a higher voltage value than the output voltage information (increase). Do). On the other hand, when the change amount data is a negative value, the output data from the adder 83 has a voltage value lower (decreases) than the output voltage information. When the change amount data has the value “0”, the output data from the adder 83 has the same voltage value as the output voltage information.

The output data from the adder 83 is
The second waveform latch circuit 84 is synchronized with the second timing signal.
Captured and retained. That is, the output voltage information from the second waveform latch circuit 84 is updated in synchronization with the second timing signal.

Here, the operation of generating the drive signal will be described based on a specific example of FIG. In this example, the waveform memory 8
The change amount data of “0” is stored in the address A of 1;
The address B stores the change amount data of + ΔV1, and the address C stores the change amount data of −ΔV2.

When the first timing signal is input in a state where the address signal indicating the address B is input to the waveform memory 81 (t1), the first waveform latch circuit 82 outputs the signal of + △ V1 stored in the address B. Change amount data in waveform memory 8
Read from 1 and hold. Thereafter, at the update timing defined by the second timing signal, for example, the second
At the rising timing of the timing signal, the second waveform latch circuit 84 captures and holds the output data from the adder 83 (t2). Here, at the first timing after the supply of the first timing signal, ΔV1 obtained by adding ΔV1 to the GND potential which is the output voltage up to that time is held as a new output voltage.

Thereafter, when the next update timing arrives after the period ΔT has elapsed, the second waveform latch circuit 84 adds 2 V, which is the sum of the output voltage ΔV1 and ΔV1.
1 (△ V1 + △ V1) is held as new output voltage data (t3).

When the next update timing arrives after the period ΔT has further elapsed, the second waveform latch circuit 84
(2 △ V1 + △ V1) is held as new output voltage data (t4).

With respect to the above address signal, when the change amount data corresponding to the address B is held in the first waveform latch circuit 82, then the content of the address signal is switched to the address A.

The address signal indicating the address A is referred to by the next input of the first timing signal (t5). That is, the first waveform latch circuit 82 reads out the change amount data of the value “0” stored in the address A from the waveform memory 81 and holds the data in accordance with the input of the first timing signal.

When the change amount data of the value “0” is held in the first waveform latch circuit 82, the output data from the adder 83 has the same voltage value as the output voltage from the second waveform latch circuit 84. Therefore, during a period in which the change amount data of the value “0” is held in the first waveform latch circuit 82, even if the update timing specified by the second timing signal arrives, the second waveform latch circuit 84 The output voltage maintains the previous voltage value V (t6, t7).

With the next input of the first timing signal, the change amount data of -ΔV2, which is the change amount data corresponding to the address C, is held in the first waveform latch circuit 82 (t
8).

When the change amount data is held, the output voltage from the second waveform latch circuit 84 decreases by ΔV2 every time the update timing comes (t9 to t1).
4).

As described above, the illustrated drive signal generation circuit 8
In this case, the waveform of the drive signal COM can be set to any shape only by outputting parameters such as an address signal and a clock signal from the control unit 194.

When the voltage value of the drive signal COM is increased, the piezoelectric vibrator 6 of the recording head 4 is charged and contracts in the element longitudinal direction, and the volume of the pressure chamber 71 is increased. Conversely, when the voltage value is reduced, the electric charge of the piezoelectric vibrator 6 is discharged and the piezoelectric vibrator 6 extends in the longitudinal direction of the element, and the volume of the pressure chamber 71 is reduced.

In the printer 1 having the above configuration, when the power is turned on, maintenance such as cleaning of the nozzle plate surface and flushing operation by the wiper blade 170 is performed so that the ink droplets can be satisfactorily ejected. Then, after maintenance is performed, characters, images, and the like on the recording paper 3 are recorded.

The flushing operation is performed during the execution period of the recording operation. For example, if a predetermined amount of printing has been performed, the printing operation is interrupted, the carriage 2 moves to the home position, and the print head 4 executes a flushing operation. Then, after the flushing operation is completed, the operation returns to the recording operation.

Further, this flushing operation is performed even after the recording is completed. After the recording, the carriage 2
Moves to the home position and stands by. In order to prevent the ink solvent from evaporating from the nozzle opening 51 during the standby, the ink is supplied to the cap member 18 at the end of recording.
Spray on the moisturizer inside 0.

When such a flushing operation is performed, the control unit 194 of the printer controller 19 functions as a flushing control unit, and when a flushing command is issued, the drive unit functions as a drive signal generation unit of the present invention. A control command is output to the signal generation circuit 8 to generate a series of flushing drive signals.

Here, in a flushing operation for discharging unnecessary ink such as thickened ink or solidified ink near the nozzle opening, such as a flushing operation immediately after turning on the power, the drive signal generating circuit 8 operates as described above. A series of flushing drive signals is generated in which a second drive signal having a large ink ejection amount per unit time is arranged on the rear side of the first drive signal capable of efficiently discharging unnecessary ink.

This flushing drive signal is, for example, as shown in FIG.
As shown in FIG. 2, the first drive signal COM1 that can efficiently discharge unnecessary ink such as thickened ink and solidified ink near the nozzle opening and the second drive signal with high ink discharge efficiency are included. The second drive signal COM2 is arranged after the first drive signal COM1. In accordance with the flushing drive signal, two-stage drive control is performed in which unnecessary ink is discharged in the first half of the flushing operation, and then ink is ejected by increasing the amount of ink discharged per unit time in the second half of the flushing operation. .

The first drive signal COM1 of the present embodiment is used for controlling the pressure chamber 71 while suppressing the meniscus (the free surface of the ink exposed at the nozzle opening 51) from being drawn into the pressure chamber 71 side.
And a first flushing pulse FP1 for rapidly contracting the pressure chamber 71 filled with the ink and ejecting ink droplets.
A plurality of P1s are connected so that P1 is supplied in a cycle T1 (see FIG. 7A).

The second drive signal COM2 is supplied to the pressure chamber 7
1 is rapidly expanded to fill the pressure chamber 71 with ink,
A plurality of second flushing pulses FP2 for rapidly contracting the pressure chamber 71 filled with ink to discharge ink droplets are provided, and adjacent second flushing pulses FP2 are connected in series in close proximity to each other. In the present embodiment, the period T
7 are connected in series at a period T2 (see FIG.

As shown in FIG. 7A, the first drive signal C
The first flushing pulse FP1 of OM1 includes an expansion element P1 that gradually increases the potential from the intermediate potential (bias level) Vm to the expansion potential VH1 at a constant gradient θ1 and an expansion that holds the expansion potential VH1 for a predetermined short time. A hold element P2 and an ejection element P3 for rapidly lowering the potential at a steep gradient θ2 from the expansion potential VH1 to the contraction potential Vm1.
And a contraction hold element P4 for holding the contraction potential Vm1 for a predetermined short period of time, and an expansion return element P5 for gradually returning the potential from the contraction potential Vm1 to the intermediate potential.

That is, the first flushing pulse FP
1 is a first amplitude W1 that is convex upward with the middle potential Vm as a boundary.
And a shape having a downwardly protruding second amplitude W2.
The voltage peak value VH2 of the second amplitude W2 is set to be smaller than the voltage peak value VH1 of No. 1.

In the first flushing pulse FP1,
The piezoelectric vibrator 6 of the recording head 4 is supplied by the supply of the expansion element P1.
Is charged, the piezoelectric vibrator 6 contracts in the element longitudinal direction, the pressure chamber 71 expands, and ink is filled. Expansion element P1
The first charging time C1 which is the supply period of the nozzle opening 51
Is preferably long enough to suppress the pull-in of the meniscus, for example, set to a value of 100 μs or more. When the first charging time C1 is set to be long as described above, the piezoelectric vibrator 6 contracts slowly and gradually.
The expansion of the pressure chamber 71 proceeds gently, and the pressure in the pressure chamber 71 is hardly reduced. As a result, the meniscus of the nozzle opening 51 can be kept calm. That is, the expansion element P1 functions as a first filling element in the present invention.

The nozzle opening 51 is formed by the expansion element P1.
In this way, it is possible to prevent the ink forming the meniscus from being greatly drawn into the pressure chamber 71, and it is possible to keep unnecessary ink such as thickened ink or solidified ink generated near the meniscus near the nozzle opening 51. .

Then, the pressure chamber 71 is rapidly contracted by the supply of the ejection element P3, and the pressure in the pressure chamber 71 is rapidly increased in accordance with the contraction, and the ink droplet is ejected. That is, the ejection element P3 functions as the first ejection element in the present invention, and rapidly contracts the pressure chamber 71 filled with ink by the expansion element P1 (first filling element) to eject ink droplets.

The nozzle element 51 is formed by the ejection element P3.
The unnecessary ink retained in the vicinity can be discharged to the outside of the recording head 4 without diffusing into the pressure chamber 71.

The first flushing pulse FP1
Then, the first charging time C1 is sufficiently long and the subsequent discharge element P
Since the supply time of No. 3 is relatively short, ink droplets are ejected by slowly expanding and contracting the pressure chamber 71 in a short time. For this reason, the trailing (satellite) of the ejected ink droplets is shorter than that of the recording drive signal at the time of normal recording in which a high frequency response is secured, and the peripheral portion of the apparatus is stained by satellite dots (mist). Less.

As shown in FIG. 7B, the second drive signal C
The second flushing pulse FP2 of OM2 includes an expansion element P6 for rapidly increasing the potential from the intermediate potential (bias level) Vm to the expansion potential VH1 at a steep gradient θ3, and an expansion hold element P7 for holding the expansion potential VH1 for a very short time.
And a steep gradient θ4 from the expansion potential VH1 to the contraction potential Vm1.
Discharge element P8 for rapidly lowering the electric potential with the contraction potential V
It comprises a contraction hold element P9 for holding m1 for a very short time and an expansion return element P10 for returning the potential from the contraction potential Vm1 to the intermediate potential.

Here, the gradient θ4 of the discharge element P8 forming a part of the second flushing pulse FP2 is steeper than the gradient θ2 of the discharge element P3 forming a part of the first flushing pulse FP1. Further, the second charging time C2, which is the supply period of the expansion element P6, is sufficiently shorter than the first charging time, and is set, for example, to several μs to several tens μs. Further, the repetition period T2 of the second flushing pulse FP2
Is the repetition period T1 of the first flushing pulse FP1
Shorter enough.

In the second flushing pulse FP2,
Due to the supply of the expansion element P6, the pressure chamber 71 expands relatively quickly, and a negative pressure is generated in the pressure chamber 71, whereby ink is rapidly filled. In other words, the expansion element P6 functions as a second filling element in the present invention, and rapidly expands the pressure chamber 71 to fill the pressure chamber 71 with ink. Expansion element P6
Immediately after the supply of the pressure chamber 71, the discharge element P8 is supplied and the pressure chamber 71 is supplied.
Are rapidly contracted and pressurized, and ink droplets are ejected from the nozzle openings 51. The ejection element P8 functions as a second ejection element of the present invention, and rapidly contracts the pressure chamber 71 filled with ink by the expansion element P6 to eject ink droplets. Further, after the supply of the expansion return element P10 is completed, the supply of the next second flushing pulse FP2 is started in a short time.

In the present embodiment, the second flushing pulse FP2 has the same shape as the print pulse constituting the recording drive signal, and the repetition period T2 of the second flushing pulse FP2 is changed to the print pulse in the recording drive signal. Is set to the same length as the repetition period. This is to reduce the amount of data for generating the drive signal.

That is, as described above, the flushing drive signal and the recording drive signal are supplied to the drive signal generation circuit 8 based on the parameters (address signals and the like) from the control unit 194.
Occurs. Therefore, it is necessary to store the supply pattern of the address signal for each shape of the drive waveform to be generated. Here, if the second flushing pulse FP2 has the same shape as the print pulse constituting the recording drive signal, and the repetition cycle is also set to the repetition cycle of the print pulse, the second drive signal COM2 uses the parameters for the recording drive signal. The amount of data for generating the drive signal can be reduced.

The first flushing pulse FP
1 and the amount of ink droplets ejected by the second flushing pulse FP2.
A large amount of ink droplets of the first flushing pulse FP1 is set.

This is because, when discharging the thickened ink or the solidified ink, the discharge of the thickened ink or the solidified ink can be performed more efficiently by discharging many ink droplets in one discharge operation. On the other hand, after the thickened ink or the solidified ink is discharged, since the ink is in an active state, that is, the ink viscosity is in a normal state, it is more preferable to continuously discharge ink droplets in a short cycle. This is because the discharge amount of the ink droplet per time can be increased.

In the illustrated flushing drive signal, the drive voltage of the first flushing pulse FP1 and the drive voltage of the second flushing pulse FP2 are both the potential difference from VH1 to Vm1 and have the same value. The drive voltage of FP1 may be set higher than the drive voltage of the second flushing pulse FP2. Thus, the amount of ink droplets ejected by the first flushing pulse FP1 can be easily increased.

When the above-mentioned flushing drive signal is supplied to the recording head 4 (piezoelectric vibrator 6), the first drive signal COM1 is supplied in the first half of the flushing operation, and unnecessary ink such as thickened ink and solidified ink is discharged. And in the second half of the flushing operation, the second drive signal COM
2 is supplied, and ink droplets are continuously discharged in a short cycle. That is, after the unnecessary ink is discharged out of the recording head 4, ink droplets are continuously discharged in a short cycle.

As described above, since the amount of ink discharged per unit time is increased after the unnecessary ink is discharged,
Even if the ink discharge amount is increased, it is possible to reliably prevent the problem that the thickened ink or the like is dispersed in the pressure chamber 71.
For this reason, the ink ejection operation performed in the latter half of the flushing with improved discharge efficiency can be completed in a short time.

As a result, unnecessary ink such as thickened ink and solidified ink can be reliably discharged, and the flushing operation time can be shortened. Further, since unnecessary ink near the nozzle opening 51 is unlikely to diffuse into the pressure chamber 71, the amount of ink consumed during the flushing operation can be reduced.

Further, since the first drive signal COM1 and the second drive signal COM2 are generated by giving parameters to the drive signal generation circuit 8, the first drive signal COM1 and the second drive signal COM2 have different waveforms by the same drive signal generation circuit 8. 1 drive signal C
OM1 and the second drive signal COM2 can be generated. As a result, the configuration of the apparatus can be simplified, and conditions such as the shape of the flushing pulse and its repetition period can be easily changed. That is, the flushing drive signal can be easily optimized.

In the flushing operation during the recording operation or the flushing operation immediately after the end of the recording operation, the ink in the pressure chamber 71 is active. That is, the ink in the pressure chamber 71 is in a good state without any troubles such as thickening and solidification. In such a case, it is convenient to perform the flushing operation only with the second drive signal COM2.

That is, since the second flushing pulse FP2 has a high frequency response, the flushing operation can be completed in a short time by performing the flushing operation only with the second drive signal COM2. Further, the amount of ink consumed during the flushing operation can be reduced.

Incidentally, the first drive signal COM1 in the first embodiment described above includes the expansion element P1 (first filling element), the expansion hold element P2, the discharge element P3 (first discharge element), the contraction hold element P4, , Expansion return element P
Although the first flushing pulse FP1 having the number 5 is connected in series, the invention is not limited to this.

For example, the first drive signal COM1 can be configured as in the second embodiment of FIG.

In the second embodiment, the expansion element P1 'for gradually increasing the potential at a constant gradient θ1 from the intermediate potential (bias level) Vm to the expansion potential VH1 and the expansion potential VH1 are held for a predetermined short time The first flushing pulse FP1 'is composed of an expansion hold element P2' that performs the first flushing pulse FP1 'and a discharge element P3 that rapidly lowers the potential at a steep gradient θ2 from the expansion potential VH1 to the intermediate potential Vm. Connect in series.

In the first flushing pulse FP1 ', the pressure chamber 71 is slowly expanded by the supply of the expansion element P1' (first filling element of the present invention), and the meniscus is suppressed from being drawn into the pressure chamber 71 side. The pressure chamber 71 is filled with ink. Also, the ink forming the meniscus at the nozzle opening 51 can be prevented from being greatly drawn into the pressure chamber 71 by the expansion element P1 ′, and the ink such as the thickened ink and the solidified ink generated near the meniscus can be prevented. Unnecessary ink can be kept near the nozzle opening 51.

Thereafter, the ejection element P3 '(first ejection element of the present invention) is supplied. Due to the supply of the ejection element P3 ', the pressure chamber 71 contracts rapidly, and the pressure in the pressure chamber 71 increases rapidly with the contraction, thereby ejecting ink droplets.
By the ejection element P3 ', unnecessary ink retained near the nozzle opening 51 can be discharged to the outside of the recording head 4 without diffusing into the pressure chamber 71.

Therefore, the first flushing pulse FP
Even if the first drive signal COM1 is constituted by 1 ', the thickened ink and the solidified ink in the vicinity of the nozzle opening 51 can be efficiently and reliably discharged.

By the way, the first flushing pulses FP1 and FP1 'of the first and second embodiments are as follows.
Both include an element that fills the pressure chamber 71 with ink while suppressing the meniscus from being drawn into the pressure chamber 71 side, and an element that ejects ink droplets by rapidly contracting the pressure chamber 71 filled with ink. However, the present invention is not limited to this configuration.

For example, an element for rapidly expanding the pressure chamber 71 to fill the pressure chamber 71 with ink and an element for rapidly contracting the pressure chamber 71 filled with ink to eject ink droplets are included. A flushing pulse may be configured to supply the next flushing pulse after the pressure fluctuation in the pressure chamber 71 due to the previous flushing pulse has converged.

Hereinafter, another embodiment configured as described above will be described.

FIG. 9 is a time chart showing a drive signal in a flushing operation according to the third embodiment of the present invention. In the third embodiment, the configuration of the device and the like are the same as those in the first embodiment. In the third embodiment,
The waveforms of the first drive signal COM1 and the second drive signal COM2 are changed by changing the parameters given to the drive signal generation circuit 8.

The third flushing pulse FP3 of the first drive signal COM1 includes an expansion element P11 for rapidly increasing the potential at a steep gradient from the intermediate potential Vm to the expansion potential VH1, and an expansion hold for holding the expansion potential VH1 for a very short time. Element P
12, an ejection element P13 for rapidly decreasing the potential from the expansion potential VH1 to the contraction potential Vm1 with a steep gradient, and a contraction hold element P14 for holding the contraction potential Vm1 for a very short time.
And an expansion return element P15 for returning the potential from the contraction potential Vm1 to the intermediate potential.

The fourth flushing pulse FP4 of the second drive signal COM2 includes an expansion element P16 for rapidly increasing the potential at a steep gradient from the intermediate potential Vm to the expansion potential VH1, and an expansion hold for holding the expansion potential VH1 for a very short time. Element P
17, an ejection element P18 for rapidly decreasing the potential from the expansion potential VH1 to the contraction potential Vm1 with a steep gradient, and a contraction hold element P19 for holding the contraction potential Vm1 for a very short time.
And an expansion return element P20 for returning the potential from the contraction potential Vm1 to the intermediate potential.

The third flushing pulse FP3 and the fourth flushing pulse FP4 have the same waveform. In the present embodiment, similarly to the second flushing pulse FP2, it has the same shape as the print pulse constituting the recording drive signal. This is to reduce the amount of data for generating the drive signal.

The first drive signal COM1 and the second drive signal COM2 correspond to the flushing pulses FP3, FP4
Are different.

That is, in the first drive signal COM1, after the pressure fluctuation in the pressure chamber 71 due to the previous third flushing pulse FP3 has converged, the next third flushing pulse FP3
Are supplied and the third flushing pulses FP3 adjacent to each other are connected in series so as to be separated from each other.

More specifically, a period T3 from the start of the supply of the first third flushing pulse FP3 to the start of the supply of the second third flushing pulse FP3, and the third period from the start of the supply of the second third flushing pulse FP3. The period T4 up to the start of the supply of the third flushing pulse FP3 is set to a time when the pressure fluctuation in the pressure chamber 71 can converge. Similarly, the time period T5 from the start of the supply of the third third flushing pulse FP3 to the start of the supply of the fourth flushing pulse FP4 is set to a time that the pressure fluctuation in the pressure chamber 71 can converge.

Further, regarding the intervals T3 and T4 between the adjacent third flushing pulses FP3,
T4 is set to be short enough to be arranged on the rear side of the first drive signal COM1. That is, the interval T4 is set shorter than the interval T3. This is the third flushing pulse FP
This is because unnecessary ink remaining near the nozzle opening 51 decreases each time 3 is supplied. That is, when the amount of unnecessary ink near the nozzle opening 51 decreases, the amount of diffusion of the unnecessary ink also decreases. Therefore, the third flushing pulse FP3
Unnecessary ink can be reliably discharged to the outside of the recording head 4 even if the supply cycle is shorter than the previous cycle. By shortening the supply cycle, the time required for the flushing operation can be shortened, and the efficiency of the flushing operation can be increased.

On the other hand, the fourth drive signal COM2
Regarding the repetition period of the flushing pulse FP4,
The cycle T2 is set to the same cycle as the print pulse repetition cycle in the recording drive signal, and the amount of ink ejected per unit time is increased.

When such a flushing drive signal is supplied, in the first half of the flushing operation, the supply of the third flushing pulse FP3 causes the ejection of ink droplets, and the ejection of unnecessary ink is accompanied by the ejection of the ink droplets. Here, since the third flushing pulse FP3 is arranged in a so-called thinned state and its repetition cycle is long, there is a time margin for the pulled-in meniscus to return to the original state. Further, since the meniscus return time is longer (the meniscus oscillation period is longer) in the thickened ink than in the ink in the better state, the longer the repetition period is, the higher the stability of the ejection operation of the thickened ink is. . As a result, the meniscus of the nozzle opening 51 can be kept calm, and the thickened ink in the meniscus portion can be prevented from diffusing to the back side,
This can be ejected.

In the latter half of the flushing operation, the first
As in the embodiment, the amount of ink discharged per unit time is increased.

Therefore, in this embodiment, too much ink need not be ejected during flushing, the amount of ink consumed by ejection can be reduced, and the effective ink amount that can be used for printing increases. Excellent.

By the way, in the third embodiment, the third
Although the waveform shape of the flushing pulse FP3 and the waveform shape of the fourth flushing pulse FP4 are made the same, the drive voltage of the third flushing pulse FP3 is changed to the fourth.
The driving voltage FP4 of the flushing pulse may be set higher.

FIG. 10 shows the third flushing pulse FP3.
13 is a time chart showing a drive signal in a flushing operation, showing a fourth embodiment in which the drive voltage of the fourth embodiment is set higher than the drive voltage of the fourth flushing pulse FP4.

In the fourth embodiment, the configuration of the device is the same as that of the above-described first embodiment.
The waveform of the flushing drive signal is changed by changing the parameters given to the flash drive signal.

The second drive signal COM2 in the present embodiment
Is the same as that of the first embodiment, and has a fourth flushing pulse FP having the same shape as the print pulse of the recording drive signal.
4 and a plurality of fourth flushing pulses FP4 are connected in series at the same repetition period T2 as during recording.

On the other hand, the first drive signal COM1 includes the expansion element P11 ', the expansion hold element P12', and the discharge element P11.
13 ', a deflation hold element P14', and an expansion return element P15 '
3 'are connected in series. Here, the third flushing pulse FP3 'and the third flushing pulse FP3 in the third embodiment have different expansion potentials. That is, the expansion potential VH2 of the third flushing pulse FP3 'is set slightly higher than the expansion potential VH1 of the third flushing pulse FP3. As a result, the drive voltage (peak value) of the third flushing pulse FP3 'becomes slightly higher, and the amount of ink ejected per pulse increases.

Then, the third flushing pulse FP
3 'are connected to each other at intervals T6 such that the pressure fluctuation in the pressure chamber 71 caused by the supply of the previous pulse can converge.

When unnecessary ink such as thickened ink is discharged by the first drive signal COM1, the ejection force of the ink droplet by the third flushing pulse FP3 'is increased, so that the thickened ink or the like is reliably discharged to the recording head 4. Can be pushed out. Further, since the adjacent third flushing pulses FP3 'are sufficiently separated from each other, the next pulse can be supplied after the pressure fluctuation in the pressure chamber 71 due to the supply of the previous pulse converges. Diffusion of the thickened ink and the like due to the pressure fluctuation can be prevented. As a result, the thickened ink can be more reliably discharged.

The flushing drive signal can be configured by combining the third and fourth embodiments. FIG. 11 is a time chart showing a drive signal in a flushing operation, showing the fifth embodiment configured as described above.

Also in the fifth embodiment, the second drive signal COM
2 includes a plurality of fourth flushing pulses FP4 having the same shape as the print pulse of the recording drive signal, and the fourth flushing pulses FP4 are connected in series at the same repetition period T2 as during recording.

On the other hand, the first drive signal COM1 is a third flushing pulse FP3 ′ in which the initially supplied pulse has a higher drive voltage than usual, and the next supplied pulse is the normal drive voltage VH1. 3 flushing pulses FP3. Further, the period T3, which is the interval between the initially supplied pulses, is set to be the longest, and the period T4, which is the interval between the subsequently supplied pulses, is set to be a period slightly shorter than the period T3. That is, the interval between the third flushing pulses (FP3, FP3 ') is set to be short enough to be arranged on the rear side of the drive signal.

When unnecessary ink is discharged by the above-described drive signal, ink is discharged by the pulse of the third flushing pulse FP3 'having an increased drive voltage at the beginning of the flushing operation, so that the amount of discharged ink increases and the viscosity of the ink increases. Can be more reliably discharged. Thereafter, the unnecessary ink is discharged in accordance with the progress of the discharge, so that wasteful ink discharge can be suppressed.

In each of the above embodiments, the pressure chamber 71
Although the pressure generating element that generates the pressure fluctuation in the inside is exemplified by the piezoelectric vibrator 6, the pressure generating element may be any element that can generate the pressure fluctuation in the pressure chamber 71.

[0137]

As described above, the present invention has the following effects.

That is, since the drive signal generation means generates a series of flushing drive signals including the first drive signal and the second drive signal, the flushing operation by the first drive signal and the flushing operation by the second drive signal are performed. Thus, the characteristics of the flushing operation can be made different.

For this reason, depending on how the first drive signal and the second drive signal are applied, unnecessary ink near the nozzle opening can be discharged first, and thereafter a large amount of ink can be discharged in a short time.

As a result, unnecessary ink such as thickened ink and solidified ink can be reliably discharged, and the flushing operation time can be shortened as a whole.

[Brief description of the drawings]

FIG. 1 is a perspective view of an ink jet recording apparatus according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a recording head.

FIG. 3 is a block diagram illustrating a configuration of a control system.

FIG. 4 is a block diagram illustrating a configuration of a drive signal generation circuit.

5 is a timing chart showing a process of generating a drive signal waveform in the drive signal generation circuit of FIG.

FIG. 6 is a time chart showing drive signals in a flushing operation.

FIG. 7 is an enlarged time chart of the first drive signal of FIG. 6;

FIG. 8 is a time chart showing a first drive signal in a flushing operation according to the second embodiment of the present invention.

FIG. 9 is a time chart showing a driving signal in a flushing operation according to the third embodiment of the present invention.

FIG. 10 is a time chart showing a drive signal in a flushing operation according to the fourth embodiment of the present invention.

FIG. 11 is a time chart showing a driving signal in a flushing operation according to the fifth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink jet recording apparatus 2 Carriage 3 Recording paper 4 Recording head 5 Ink cartridge 6 Piezoelectric vibrator 7 Flow path unit 8 Drive signal generation circuit (drive signal generation means) 11 Guide member 12 Drive pulley 13 Idle pulley 14 Timing belt 15 Pulse Motor 16 Platen 17 Cleaning mechanism 18 Capping mechanism 19 Printer controller 40 Base 42 Fixed substrate 43 Storage chamber 44 Electric drive system of recording head 46 Vibrator unit 48 Ink supply pipe 50 Nozzle plate 51 Nozzle opening 55 Flow path forming plate 60 Vibration plate Reference Signs List 61 stainless steel plate 62 elastic film 70 island portion 71 pressure chamber 72 common ink chamber 73 ink supply path 80 wave forming circuit 81 waveform memory 82 first waveform latch circuit 83 adder 84 second waveform latch circuit 86 Digital-to-analog converter 88 Voltage amplifier circuit 89 Current amplifier circuit 94 Shift register 95 Latch circuit 96 Level shifter 97 Switch 170 Wiper blade 171 Wiper holder 180 Cap member 191 External interface 192 RAM 193 ROM 194 Control unit 195 Oscillator circuit 196 Internal interface COM1 First Drive signal COM2 Second drive signal

Claims (13)

[Claims] 1. A print head for changing a pressure in a pressure chamber communicating with a nozzle opening in accordance with a driving signal, and ejecting ink droplets from the nozzle opening by the pressure change, and a driving signal generating means capable of generating a flushing driving signal. With
In an ink jet recording apparatus for performing a flushing operation of forcibly discharging ink in a pressure chamber by supplying a flushing drive signal to a printhead, the drive signal generation unit converts a first drive signal and a second drive signal into two. An ink jet recording apparatus for generating a series of flushing drive signals provided. 2. The first drive signal includes: a first filling element for filling the pressure chamber with ink while suppressing the meniscus from being drawn into the pressure chamber; and a pressure chamber filled with ink by the first filling element. 2. The method according to claim 1, further comprising a first flushing pulse including a first ejection element for ejecting an ink droplet by contracting the first flushing pulse, and connecting the plurality of first flushing pulses in series. Ink jet recording device. 3. The second drive signal includes a second filling element for rapidly expanding the pressure chamber and filling the pressure chamber with ink, and rapidly contracting the pressure chamber filled with ink by the second filling element. A plurality of second flushing pulses including second ejection elements for ejecting ink droplets by
3. The ink jet type recording apparatus according to claim 2, wherein the flushing pulses are arranged close to each other and connected in series. 4. The ink jet recording apparatus according to claim 3, wherein the ejection amount of the ink droplet by the first flushing pulse is set to be larger than the ejection amount of the ink droplet by the second flushing pulse. 5. The ink jet recording apparatus according to claim 3, wherein the waveform of the second flushing pulse has the same shape as a print pulse. 6. The first driving signal includes a third filling element for rapidly expanding the pressure chamber and filling the pressure chamber with ink, and rapidly contracting the pressure chamber filled with ink by the third filling element. A plurality of third flushing pulses including a third ejection element for ejecting ink droplets through the second flushing pulse, so that the next third flushing pulse is supplied after the pressure fluctuation in the pressure chamber caused by the previous third flushing pulse converges. 2. The ink jet recording apparatus according to claim 1, wherein the matching third flushing pulses are separated from each other and connected in series. 7. The second drive signal causes a pressure chamber to expand rapidly to fill the pressure chamber with ink, and causes the pressure chamber filled with ink to contract rapidly by the fourth filling element. A plurality of fourth flushing pulses including a fourth ejection element for ejecting an ink droplet by
7. The ink jet recording apparatus according to claim 6, wherein the flushing pulses are arranged close to each other and connected in series. 8. The ink jet recording apparatus according to claim 7, wherein the waveform shape of the third flushing pulse and the waveform shape of the fourth flushing pulse are the same. 9. The ink jet recording apparatus according to claim 7, wherein the drive voltage of the third flushing pulse is set higher than the drive voltage of the fourth flushing pulse. 10. The method according to claim 6, wherein a waveform of at least one of the third flushing pulse and the fourth flushing pulse has the same shape as a print pulse. Ink jet recording device. 11. The ink-jet type according to claim 6, wherein an interval between adjacent third flushing pulses is set short enough to be arranged on the rear side of the drive signal. Recording device. 12. When the ink in the pressure chamber is active, such as at the end of printing or after a cleaning operation, the driving signal generating means generates a flushing driving signal consisting of only the second driving signal. Item 1 to Item 11
An ink jet recording apparatus according to any one of the above. 13. The driving signal generating unit includes: an output voltage information holding unit that holds output voltage information for defining a shape of a driving signal; a change amount information holding unit that holds change amount information; And addition means for adding the change amount information to obtain the addition voltage information. The switching means outputs the change amount information output from the change amount information holding means to the addition means while adding the addition voltage information each time the update timing arrives. 13. The ink jet recording apparatus according to claim 1, wherein a drive signal of an arbitrary shape is generated by causing the output voltage information holding means to hold the drive signal as new output voltage information.