JP2004114703A - Ink drop ejector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance print quality by switching a printing waveform based on print data being fed sequentially in correspondence with one actuator and the temperature of an apparatus. <P>SOLUTION: The ink ejector comprises a print head having an ink chamber being filled with ink and an actuator for ejecting ink from the ink chamber, a plurality of means 42, 43 and 44 for storing print data being fed sequentially in correspondence with one actuator, and a transfer data generating means generating data signals for driving the actuator based on the print data delivered from respective storage means and the temperature of an apparatus. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to an ink droplet ejecting apparatus that ejects ink to form an image on a recording medium.

イ ン ク ジ ェ ッ ト Conventionally, there is an ink jet type as a recording apparatus which is easy to increase the number of gradations and color. Among these recording apparatuses, drop-on-demand type ink droplet ejecting apparatuses that eject ink for printing are becoming popular due to their good ejection efficiency and low running cost.

As a drop-on-demand type ink ejecting apparatus, for example, there is a shear mode type ink ejecting apparatus using a piezoelectric material described in Japanese Patent Application Laid-Open No. 63-247051 (Patent Document 1). FIGS. 23 and 24 show an example of this type of ink droplet ejecting apparatus.

The print head 600 constituting the ink droplet ejecting apparatus includes a bottom wall 601, a top wall 602, and a shear mode type actuator wall 603 sandwiched between the walls 601 and 602. The actuator wall 603 is bonded to the top wall 602 and is made of a piezoelectric material upper wall 605 polarized in the direction of arrow 609, and is bonded to the bottom wall 601 and is made of a piezoelectric material lower wall 607 polarized in the direction of arrow 611. Consists of Two adjacent actuator walls 603 form a pair, form an ink chamber 613 therebetween, and form an air chamber 615 between the adjacent actuator walls 603.

A nozzle plate 617 having a nozzle 618 is fixed to one end of each ink chamber 613, and an ink supply source (not shown) such as an ink cartridge is connected to the other end via a manifold 626. The manifold 626 includes a front wall 627 having an opening communicating with each of the ink chambers 613, and a rear wall 628 for sealing between the walls 601 and 602, and is provided between the ink supply source and the two walls 627 and 628. The supplied ink is distributed to each ink chamber 613.

(4) Electrodes 619 and 621 are provided on both side surfaces of each actuator wall 603. That is, the electrode 619 is provided on the actuator wall 603 on the ink chamber 613 side, and the electrode 621 is provided on the actuator wall 603 on the air chamber 615 side and the outer peripheral side of the print head 600. Each electrode 619 provided in each ink chamber 613 is connected to the drive circuit 21. The drive circuit 21 generates a drive signal, which will be described later, based on the control of the control circuit 22, and applies the drive signal to each electrode 619. The other electrode 621 is connected to the ground 623.

(4) When the drive circuit 21 applies a voltage to the electrode 619 of each ink chamber 613, each actuator wall 603 undergoes piezoelectric thickness shear deformation in a direction to increase the volume of the ink chamber 613. An example of this operation is shown in FIG. When a predetermined voltage E (V) is applied to the electrode 619 of one ink chamber 613, an electric field is generated on the actuator walls 603 and 603 on both sides of the ink chamber in the directions of arrows 631 and 631 perpendicular to the polarization direction. Then, the piezoelectric thickness shear deformation of the actuator walls 603 and 603 occurs in the direction in which the volume of the ink chamber 613 increases. At this time, the pressure in the ink chamber 613 including the vicinity of the nozzle 618 decreases.

(4) Then, the application of the voltage E (V) is maintained for the one-way propagation time T of the pressure wave in the ink chamber 613. In the meantime, ink is supplied from the aforementioned ink supply source. Note that the one-way propagation time T is a time in which the pressure wave of the ink in the ink chamber 613 propagates in one direction in the longitudinal direction of the ink chamber 613, and the length L of the ink chamber 613 and the time in the ink inside the ink chamber 613. It is calculated by the equation T = L / a based on the sound speed a.

According to the pressure wave propagation theory, when the one-way propagation time T elapses from the application of the voltage E, the pressure in the ink chamber 613 reverses and turns to a positive pressure. The applied voltage is returned to 0 (V). Then, the actuator walls 603 and 603 return to the state before deformation shown in FIG. 23, and pressure is applied to the ink. At this time, the pressure that has turned positive and the pressure generated by the return of the actuator walls 603 and 603 are added, and a relatively high pressure is generated in the vicinity of the nozzle 618 of the ink chamber 613, and the ink from the nozzle 618 Is injected. The ejected ink adheres to the surface of a recording medium such as printing paper, and an image is formed on the recording medium.

Patent Documents JP-A-9-29960 (Patent Document 2), JP-A-9-29961 (Patent Document 3) and JP-A-9-48112 (Patent Document 4) previously proposed by the present applicant. As described above, after the ejection operation in which the pressure wave vibration is generated in the ink in the ink chamber 613 and the ink is ejected from the nozzle 618 ends, the offset operation in which the residual pressure wave vibration of the ink in the ink chamber 613 almost cancels out. Execute Specifically, after the driving waveform for the main injection, one pulse is added accompanying the driving waveform. This canceling operation is performed by temporarily setting the voltage applied to the electrode 619 to a voltage E (V) at a predetermined timing, and then returning the voltage to 0 (V) to increase or decrease the volume of the ink chamber 613. By this canceling operation, the residual pressure wave vibration in the ink chamber 613 converges early, preventing the occurrence of an accidental drop in which ink is undesirably ejected from the nozzle 618 due to the residual pressure wave vibration, and the next print command. It is possible to shift to the processing for at an early stage. Therefore, a more accurate image can be formed on the recording medium, and the printing speed can be improved satisfactorily.

Japanese Patent Application Laid-Open No. H10-202858 (Patent Document 5) proposed by the present applicant discloses that after performing an ejection operation of ejecting ink from the nozzle 618 at a predetermined cycle timing, the predetermined period is used. If there is no print command at the next cycle timing corresponding to the timing, the cancel operation is executed, and if there is a print command at the next cycle timing, the cancel operation is not executed. In other words, if there is no print command at the next cycle timing corresponding to the predetermined cycle timing, there is a possibility that an accidental drop may occur, so that a canceling operation is performed, and a good image free from contamination due to ink scattering is formed. So that When a print command is issued at the next cycle timing, the residual pressure wave vibration in the ink chamber 613 is positively used, and the residual pressure wave vibration and the pressure generated by the print command at the next cycle timing are used. By generating a large pressure wave vibration by adding the wave vibration and ejecting a large ink droplet from the nozzle 618, the print density is increased so that a thick and clear image is formed.

JP-A-63-247051 JP-A-9-29960 JP-A-9-29961 JP-A-9-48112 JP-A-10-202858

By the way, the execution / non-execution of the above-described canceling operation is not only selectively switched between when there is no print command at the next (later) cycle timing corresponding to the predetermined cycle timing and when there is no print command, but also at the predetermined timing. By selectively switching between when there is no print command and when there is no print command at the cycle timing before the cycle timing, it is possible to effectively suppress meniscus vibration of ink, and the droplet ejection speed and ejection It is considered that ink droplets having a desired volume can be obtained stably, and the printing quality can be further improved.

Also, since the viscosity and other characteristics of the ink fluctuate according to the temperature conditions and use conditions of the apparatus, it is desired that the selective switching can be arbitrarily and easily performed even in response to the fluctuation. Furthermore, it is desired that a stop pulse for performing a canceling operation can be reliably generated with a simple configuration based on the history of print data before and after the printing operation, and that the restrictions on the print waveform when performing the canceling operation are relaxed. Was.

SUMMARY OF THE INVENTION The present invention has been made to satisfy the above-mentioned demands, and an object of the present invention is to switch a print waveform based on print data supplied before and after corresponding to one actuator and the temperature of the apparatus. Another object of the present invention is to improve the printing quality.

In order to achieve the above object, an ink droplet ejecting apparatus according to the present invention comprises: a print head having an ink chamber filled with ink and an actuator for ejecting ink from the ink chamber; A plurality of storage means for respectively storing the print data supplied as data, and a data signal for driving the actuator based on the print data output from each of the plurality of storage means and the temperature of the apparatus. Transfer data generating means for performing the transfer.

In the above configuration, preferably, the apparatus further comprises means for generating a plurality of pulse clocks corresponding to each printing cycle, and selectively transmitting the plurality of pulse clocks to the actuator by the data signal generated by the transfer data generating means. Output to drive the actuator.

Also, the ink droplet ejecting apparatus of the present invention outputs a print head having an ink chamber filled with ink and an actuator for ejecting ink from the ink chamber, and a plurality of pulse clocks corresponding to each printing cycle. Means, a plurality of storage means for respectively storing the print data supplied before and after corresponding to one of the actuators, and print data output from each of the plurality of storage means and the temperature of the apparatus. And a circuit for selectively outputting the plurality of pulse clocks to the actuator.

In the above configuration, preferably, the circuit that selectively outputs the pulse clock is a transfer data generating unit that outputs a data signal corresponding to the plurality of pulse clocks based on the logical operation, and the circuit that outputs the data signal based on the data signal. A gate circuit for selectively outputting a plurality of pulse clocks to the actuator.

Preferably, the storage means includes three storage means for storing predetermined print data, print data immediately before the print data, and print data immediately after the print data.

More preferably, the data signal includes additional pulse data added to the ejection pulse data, serially inputs the ejection pulse data and the additional pulse data, performs parallel conversion corresponding to the ink chamber, and performs each printing. And a drive circuit for selectively outputting a plurality of pulse clocks corresponding to a cycle to the actuator based on the ejection pulse data and the additional pulse data.

Alternatively, the data signal includes additional pulse data added to the ejection pulse data, and the circuit converts the ejection pulse data and the additional pulse data into parallel corresponding to the ink chambers, respectively. A switching circuit for selectively outputting pulse data, and a plurality of pulse clocks corresponding to each of the printing cycles with the ejection pulse data and the additional pulse data output from the switching circuit; A driving circuit including a gate circuit for outputting data may be further provided.

Further, the plurality of storage means respectively store the serially transferred print data and perform parallel conversion, and the circuit for selectively outputting the plurality of pulse clocks includes: Generating ejection pulse data based on the printing data and additional pulse data added to the ejection data based on the printing data output from the apparatus and the temperature of the apparatus. Thus, a plurality of pulse clocks corresponding to each printing cycle may be selectively output to the actuator.

According to the present invention, a data signal for driving the actuator is generated based on the print data output from each of the plurality of storage units and the temperature of the apparatus. For example, print data is lost during continuous printing. In such a case, the printing waveform can be appropriately switched according to the temperature of the apparatus, and the ejection can be stably performed.

In addition, a plurality of pulse clocks are generated corresponding to each printing cycle, and the plurality of pulse clocks are selectively output to the actuator based on the data signal generated by the transfer data generating unit, and the actuator is driven to perform comparison. Injection can be performed stably with a simple configuration.

Further, the storage means comprises three storage means for storing predetermined print data, print data immediately before and print data immediately after, so that print data immediately before and after one print data are stored together with the temperature of the apparatus. It can be used for generating a data signal, and the injection can be more appropriately stabilized.

Hereinafter, an ink ejecting apparatus according to an embodiment of the present invention will be described with reference to the drawings. The mechanical configuration of the print head 600 in the ink ejecting apparatus according to each embodiment is the same as that shown in FIGS.

FIG. 1 is a perspective view showing a schematic configuration of an ink jet printer common to each embodiment including the ink ejecting apparatus of the present invention. The guide rod 501 and the guide member 502 are bridged between the printer frame side plates 503. The carriage 504 is slidably supported by the guide rod 501 and the guide member 502, respectively, is fixed to the belt 505, and is driven by a carriage motor (CR motor) 506 to reciprocate. The belt 505 is wound around two pulleys 507 arranged near both ends of the guide rod 501 and the guide member 502. One pulley 507 is connected to the drive shaft of the CR motor 506.

The carriage 504 is provided with a print head unit 508 having a print head 600 and a drive circuit 21 composed of a one-chip IC described later. The drive circuit 21 is connected to a control circuit 22 (FIG. 2) of the printer main body via a flexible harness cable. At the rear of the print head unit 508, an ink cartridge 509 as an ink supply source for supplying ink to each nozzle 618 of the print head 600 is detachably mounted. At a position facing the print head 600, a transport mechanism LF that transports the print paper P is provided. The transport mechanism LF transports the printing paper P at right angles to the traveling direction of the carriage 504 by rotation of a platen roller 511 that is rotated by driving a transport motor (LF motor) 510. The roller shaft 512 of the platen roller 511 is rotatably supported by the printer frame side plate 503.

維持 A maintenance / recovery mechanism RM for maintaining / recovering the ink ejection operation of the print head 600 is provided on the side of the transport mechanism LF. The maintenance / recovery mechanism RM includes a suction mechanism 513 and a cap 514. The suction mechanism 513 is generated when ink is dried, bubbles are generated inside the print head 600, or ink droplets adhere to the outer surface of the nozzle plate 617 of the nozzle 618 during use of the print head 600. In order to eliminate the ejection failure, the cap 514 is brought into close contact with the nozzle plate 617 to suck ink from the nozzle 618. The cap 514 also has a function of covering the outer surface of the nozzle plate 617 and preventing drying of the ink when the inkjet printer is not used.

FIG. 2 is a block diagram illustrating an electrical configuration of an inkjet printer including the ink ejecting apparatus according to the first embodiment.

The control system of the inkjet printer includes a microcomputer 11, a ROM 12, and a RAM 13 each having one chip. The microcomputer 11 includes an operation panel 14 for a user to give a printing instruction, a motor driving circuit 15 for driving a CR motor 506, a motor driving circuit 16 for driving an LF motor 510, and a recording medium. The paper sensor 17 for detecting the leading end of the printing paper P, the origin sensor 18 for detecting the origin position of the carriage 504, the position sensor 19 for detecting the running position of the carriage 504, and the like are connected.

The print head 600 is driven by the drive circuit 21, and the drive circuit 21 is controlled by the control circuit 22. That is, as shown in FIG. 24, each electrode 619 provided in each ink chamber 613 of the print head 600 is connected to the drive circuit 21. The drive circuit 21 generates a drive signal suitable for the print head 600 based on the control of the control circuit 22, and applies the drive signal to each electrode 619.

The microcomputer 11, the ROM 12, the RAM 13, and the control circuit 22 are connected via an address bus 23 and a data bus 24. The microcomputer 11 generates a print timing signal TS and a control signal RS according to a program stored in the ROM 12 in advance, and transfers the signals TS and RS to the control circuit 22. The control circuit 22 and the drive circuit 21 constitute a control device described in claims.

The control circuit 22 includes a gate array, and is print data for forming the print data on a recording medium based on the print data stored in the image memory 25 in accordance with the print timing signal TS and the control signal RS. It generates transfer data DATA, a transfer clock TCK synchronized with the transfer data DATA, a strobe signal STB, and a print clock ICK, and transfers these signals DATA, TCK, STB, and ICK to the drive circuit 21. Further, the control circuit 22 causes the image memory 25 to store print data transferred from an external device such as a personal computer 26 via the Centronics interface 27. Then, the control circuit 22 generates a Centronics data reception interrupt signal WS based on the Centronics data transferred from the personal computer 26 or the like via the Centronics interface 27, and transfers the signal WS to the microcomputer 11. I do. The signals DATA, TCK, STB, and ICK are transferred via a harness cable 28 that connects the control circuit 22 of the printer main body and the drive circuit 21 on the carriage 504.

FIG. 3 is a block diagram showing the internal configuration of the drive circuit 21. Here, a drive circuit 21 for driving a 64-channel multi-nozzle head provided with 64 ink chambers 613 of the print head 600 will be exemplified. The drive circuit 21 includes a serial-parallel converter 31, a data latch 32, an AND gate 33, and an output circuit 34. The serial-parallel converter 31 is composed of a shift register having a length of 64 bits, receives the transfer data DATA serially transferred in synchronization with the transfer clock TCK from the control circuit 22, and transfers the transfer data DATA in accordance with the rise of the transfer clock TCK. By converting data DATA into parallel data PD0 to PD63, serial-parallel conversion of transfer data DATA is performed.

(4) The data latch 32 latches each of the parallel data PD0 to PD63 in accordance with the rise of the strobe signal STB transferred from the control circuit 22. The 64 AND gates 33 take the logical product of the parallel data PD0 to PD63 output from the data latch 32 and the print clock ICK transferred from the control circuit 22, respectively. , And generates the respective drive data A0 to A63 which are the result of the logical product of. The 64 output circuits 34 generate drive signals suitable for the print head based on the respective drive data A0 to A63, and output the respective drive signals to the electrodes 619 of the ink chambers 613 of the print head 600. Incidentally, when the print head 600 is not 64 channels, the bit length of the serial-parallel converter 31 and the respective numbers of the AND gates 33 and the output circuits 34 are set to be the same as the number of channels of the print head 600. Good.

FIG. 4 is a block diagram showing a main configuration inside the control circuit 22 (gate array). Here, as in the case of the drive circuit 21, an example in which the print head 600 is a 64-channel multi-nozzle head is illustrated. The control circuit 22 includes a data setting circuit 41, a serial-parallel converter (conversion unit) 42, a first shift register 43, and a second shift register 44, which constitute three data storage units, and a transfer data generation unit 45. (Additional pulse data generating means) and a controller circuit 47. The data setting circuit 41 reads the print data stored in the image memory 25 in parallel, and outputs the print data to a 64-bit serial-parallel conversion circuit 42 in accordance with a setting command MS.

The serial-parallel conversion circuit 42 parallel-inputs and holds print data Ch0 to Ch63 of each channel of the data setting circuit 41 in accordance with a serial-parallel conversion control signal SPC, and in accordance with the rise of a shift clock (not shown). The data is serially output from the serial output terminal OUT one bit at a time starting from the leading print data Ch0. As a result, the print data is subjected to parallel-serial conversion, and at the same time, the print data sequentially output from the serial output terminal OUT is output (A) to the transfer data generation unit 45, and the first shift register 43 having a 64-bit length is used. To the serial input terminal IN1.

The first shift register 43 serially inputs and holds the respective print data Ch0 to Ch63 serially output from the serial-parallel conversion circuit 42 in accordance with the first shift register control signal SRC1, and, in accordance with the rising edge of the shift clock, The respective print data are serially output one bit at a time from the leading data Ch0 from the serial output terminal OUT and output (B) to the transfer data generator 45. The data is output by switching the first shift register control signal SRC1. Is input to the serial input terminal IN2 again.

The second shift register 44 serially inputs and holds the print data Ch0 to Ch63 serially output from the first shift register 43 in accordance with the second shift register control signal SRC2, and holds the print data in accordance with the rise of the shift clock. Each print data is serially output (C) to the transfer data generation unit 45 from the serial output terminal OUT one bit at a time starting from the leading data Ch0.

The transfer data generation unit 45 functions as additional pulse data generation means, and print data Ch0 to Ch0 serially output from the serial-parallel conversion circuit 42, the first shift register 43, and the second shift register 44, respectively. Ch63 is input, and the logical product of the above three print data is calculated according to the transfer data control signal PAT [7-0]. That is, the output (A) of the serial-parallel conversion circuit 42 becomes ejection data immediately after the one dot, the output (B) of the first shift register 43 becomes ejection data of the dot, and the second shift register 44 Is the ejection data immediately before the dot, and a predetermined logical operation is performed based on these three ejection data. The transfer data control signal PAT [7-0] may be appropriately determined according to the temperature condition and the use condition. The transfer data generation unit 45 outputs the transfer data DATA (D) to the drive circuit 21.

As shown in FIG. 6, the transfer data DATA (D) cancels the ejection pulse data FD for the ejection operation for ejecting ink from the nozzles 618 of the print head 600 and the residual pressure wave vibration in the ink chamber 613. The stop pulse data SD for the offset operation is included. Further, the controller circuit 47 generates signals MS, SPC, SPC1, SPC2 for controlling the circuits 41 to 44, 45 according to the print timing signal TS and the control signal RS transferred from the microcomputer 11. At the same time, it generates a transfer data control signal PAT [7-0], a strobe signal STB synchronized with the transfer data DATA, a transfer clock TCK, and a print clock ICK.

When the print head 600 does not have 64 channels (the number of ink chambers), the bit length of each serial-parallel conversion circuit 42 and shift registers 43 and 44 may be the same as the number of channels of the print head 600. In the drive circuit 21, the parallel data PD0 to PD63 output from the serial-parallel converter 31 that performs serial-parallel conversion of the transfer data DATA correspond to the respective ink chambers 613 of the print head 600. . Therefore, in the control circuit 22, each bit of the transfer data DATA and each print data Ch0 to Ch63 correspond to each ink chamber 613 of the print head 600. That is, a drive signal to be applied to the electrode 619 of each ink chamber 613 is generated according to each bit of the transfer data DATA and each print data Ch0 to Ch63, and the ejection of the ink from the nozzle 618 in the ejection operation and the offset operation is controlled. Is done.

FIG. 5 shows an example of a logic circuit constituting the transfer data generation unit 45. This logic circuit is composed of eight AND circuits and one OR circuit which receives an output of the AND circuit as an input. A transfer data control signal PAT [ 7-0] and the data A, B, and C (B is the one-dot data, A is the data immediately after the dot, and C is the data immediately before the dot) to the transfer data generation unit 45 described above. Is done. Each of the AND circuits is supplied with the data A, B, and C via an inverting input terminal or not so as to generate all combinations of the data A, B, and C. One of [7-0] is input. Therefore, by appropriately selecting the contents of the transfer data control signals PAT7 to PAT0, any one of the print data A, B, and C can be output or any combination of the print data A, B, and C can be output. Signal can be output. FIG. 5B shows all combinations of the print data A, B, and C and the transfer data control signal PAT [7-0] indicating the combination. For example, by setting the PAT 7 to “1”, an additional pulse (stop pulse) signal is generated only when the print data A, B, C is a combination of “1, 1, 1”, and the transfer data is output from the output terminal of the OR circuit. Output as DATA (D). “1” indicates the presence of the ejection dot, and “0” indicates the absence of the ejection dot. In PAT0 to PAT7, the logic level “H” is indicated by “1” and the logic level “L” is indicated by “0”.

Next, the operation of the ink ejecting apparatus according to the present embodiment configured as described above will be described. FIG. 6 is a time chart of the print clock ICK, the strobe signal STB, and the transfer data DATA. The transfer data DATA includes stop pulse data SD and ejection pulse data FD, and one stop pulse data SD and one ejection pulse data FD are transferred at each timing of a predetermined printing cycle. The strobe signal STB and the print clock ICK are transferred at predetermined print cycle timings in correspondence with the stop pulse data SD and the ejection pulse data FD of the transfer data DATA.

(4) At the timing of each printing cycle, the offset operation can be performed after the end of the ejection operation. That is, as shown in FIG. 6, when the (n-1) th printing is performed at a certain printing cycle Tm-1 and the nth printing is performed at the next printing cycle Tm, each printing cycle Tm-1,. At Tm, as the print clock ICK, after the ejection pulse clock ICKf corresponding to the ejection pulse data FD is transferred, the stop pulse clock ICKs corresponding to the stop pulse data SD is transferred.

In the print cycle Tm-1, the transfer data DATA is such that after the stop pulse data SDn-1 for the (n-1) th print is transferred, the ejection pulse data FDn for the nth print is transferred. . Then, in the print cycle Tm, the transfer pulse DATA is transmitted after the stop pulse data SDn for the n-th print and then the ejection pulse data FDn + 1 for the (n + 1) -th print. Further, in the printing cycle Tm-1, the strobe signal STB becomes n-1 after the strobe signal STBfn-1 corresponding to the ejection pulse data FDn-1 (not shown) for the (n-1) th printing is transferred. The strobe signal STBsn-1 corresponding to the stop pulse data SDn-1 for the second printing is transferred. In the printing cycle Tm, the strobe signal STB is the strobe signal STBfn corresponding to the ejection pulse data FDn for the n-th printing, and then the strobe signal STB corresponding to the stop pulse data SDn for the n-th printing. Signal STBsn is transferred.

In other words, in the printing cycle Tm-1, the printing clock ICK becomes n-th after the firing pulse clock ICKfn-1 corresponding to the firing pulse data FDn-1 (not shown) for the (n-1) th printing is transferred. The stop pulse clock ICKsn-1 corresponding to the stop pulse data SDn-1 for the first printing is transferred. Then, in the printing cycle Tm, the printing clock ICK corresponds to the stop pulse data SDn for the n-th printing after the firing pulse clock ICKfn corresponding to the firing pulse data FDn for the n-th printing is transferred. The stop pulse clock ICKsn is transferred.

Hereinafter, the operation of the drive circuit 21 will be described with reference to FIG. When the logic level of the print clock ICK is “H”, the output of each AND gate 33 of the drive circuit 21 is determined according to the output state of the data latch 32, that is, the content of the transfer data DATA. Further, when the logic level of the print clock ICK is “L”, the output of each AND gate 33 of the drive circuit 21 is in a disabled state and the logic level is “L” regardless of the output state of the data latch 32. That is, the print clock ICK functions as an enable signal when each AND gate 33 generates each of the drive data A0 to A63.

Therefore, when the logic level of the print clock ICK is "H" and the transfer data DATA output from the data latch 32, that is, the logic level of the parallel data PD0 to PD63 is "H", the AND data to which the parallel data is input is set. The logic level of the drive data generated by the gate 33 also becomes “H”, and the output circuit 34 to which the drive data is input generates a drive signal and outputs it to the electrode 619 of the corresponding ink chamber 613 of the print head 600. When the logical level of the transfer data DATA output from the data latch 32, that is, the parallel data PD0 to PD63 is "L", even if the logical level of the print clock ICK is "H", the parallel data is input. The logic level of the drive data generated by the AND gate 33 becomes “L”, and the output circuit 34 to which the drive data is input does not generate a drive signal.

Therefore, as shown in FIG. 6, when the ejection pulse clock ICKfn of the print clock rises at the timing t1 in the print cycle Tm in the presence of the transfer data DATA, as described with reference to FIG. An electric field is generated, the volume of the ink chamber 613 increases, and the pressure in the ink chamber 613 including the vicinity of the nozzle 618 decreases. After that, while the ink flows into the ink chamber 613, the pressure due to the pressure wave vibration generated by the increase in the volume increases and turns to a positive pressure, and reaches a peak near the time when the one-way propagation time T elapses. .

The pulse width of the ejection pulse clock ICKfn is set to be the same as the one-way propagation time T. Therefore, the ejection pulse clock ICKfn falls at the timing t2 after the one-way propagation time T has elapsed. Then, the volume of the ink chamber 613 decreases, and the pressure generated thereby and the above-mentioned positive pressure are added, and a relatively high pressure is generated near the nozzle 618 of the ink chamber 613, and the ink from the nozzle 618 Is performed, an ink ejection operation is performed. The ejected ink adheres to the surface of the printing paper P, and an image is formed on the printing paper P.

(4) Thereafter, when the stop pulse clock ICKsn rises in the presence of the transfer data DATA at timing t3 before the pressure of the ink chamber 613 changes from positive to negative, the pressure, which is still positive, rapidly decreases. Then, when the stop pulse clock ICKsn falls at the timing t4 after the pressure has turned negative, the pressure that has turned negative suddenly increases. For this reason, the vibration of the pressure wave is cancelled, and the canceling operation in which the vibration rapidly converges is executed. When the pressure wave vibration is canceled in this way, undesired ejection of the ink from the nozzle 618 is prevented, and the process can be shifted to the process for the next print command at an early stage. Therefore, a more accurate image can be formed on the printing paper P, and the printing cycle can be shortened and the printing speed can be improved satisfactorily.

The pulse width W of the stop pulse clock ICKsn is set to 0.5 times the one-way propagation time T. The stop pulse clock ICKsn cancels the pressure wave vibration as described above, and the pulse width W is set to a short value that is significantly different from the odd multiple of the one-way propagation time T. Does not eject ink from the nozzle 618. The time d from the timing t2 at which the ejection pulse clock ICKfn falls to a timing tM intermediate between the timing t3 at which the stop pulse clock ICKsn rises and the timing t4 at which it falls is set to 2.5 times the one-way propagation time T. ing. In the ink ejection operation and the cancel operation, the voltage of the drive signal generated by the output circuit 34 is the same.

FIG. 7 is a time chart of a section in which the stop pulse data SDn-1 is transferred as the transfer data DATA at the timing of the printing cycle Tm-1 shown in FIG. FIG. 8 is a time chart of a section in which the ejection pulse data FDn is transferred as the transfer data DATA at the timing of the printing cycle Tm-1 shown in FIG.

Hereinafter, the operation of the control circuit 22 in the stop pulse data transfer section will be described with reference to FIG. In the same transfer section, the serial-parallel conversion circuit 42 inputs the print data Ch0n + 1 to Ch63n + 1 for the (n + 1) th print in parallel from the data setting circuit 41, and sequentially starts with the leading print data Ch0n + 1 according to the rise of the shift clock. Serial output is performed from the serial output terminal OUT bit by bit. The first shift register 43 stores print data Ch0n to Ch63n for the n-th printing. The first shift register 43 serially outputs one bit at a time from the serial output terminal OUT from the top print data Ch0n in accordance with the rise of the shift clock. The second shift register 44 stores print data Ch0n-1 to Ch63n-1 for the (n-1) th printing. The second shift register 44 serially outputs one bit at a time from the serial output terminal OUT sequentially from the leading print data Ch0n-1 according to the rise of the shift clock. Here, the first shift register 43 inputs the print data Ch0n + 1 to Ch63n + 1 serially output from the serial-parallel conversion circuit 42 to the serial input terminal IN1. Further, the second shift register 44 inputs the print data Ch0n to Ch63n serially output from the first shift register 43 to the serial input terminal IN.

The transfer data generator 45 receives the three serial outputs and the transfer data control signal, and performs a predetermined logical operation. Now, the transfer data control signal PAT [7-0] = [0,0,0,0,1,0,0,0] (where each data corresponds to the input terminal in the figure in order from the top) By setting only PAT3 to “1”, “1” is output from the AND gate corresponding to PAT3 only when A = 0, B = 1, and C = 1. In other words, the transfer data DATA (D) becomes "1" with respect to the dot (B) having an ejection dot before (C) and no ejection dot after (A), and a stop pulse can be added.

Next, the operation of the control circuit 22 in the ejection pulse data transfer section will be described with reference to FIG. In the transfer section, when the transfer of the stop pulse data is completed, the first shift register 43 stores the print data Ch0n + 1 to Ch63n + 1, and the print data is stored according to the rising edge of the shift clock. The data is serially output from the serial output terminal OUT one bit at a time starting from the first print data Ch0n + 1. The print data Chn + 1 serially output from the serial output terminal OUT is input again to the serial input terminal IN2. By setting the transfer data control signal PAT [7-0] = [1,1,0,0,1,1,0,0], PAT7 and PAT6 shown in FIG. , PAT3, and PAT2 output data corresponding to B from one of the AND gates. As a result, the serial output (B) is output as the ejection pulse data as the transfer data DATA (D).

As described in detail above, in the control circuit 22 of the ink ejecting apparatus according to the present embodiment, for the n-th printing in the printing cycle Tm, the printing for the (n + 1) -th printing data in the corresponding next printing cycle is performed. When there is no command and a print command is issued for print data for the (n-1) th print in the previous print cycle, stop pulse data is generated and a cancel operation is executed. With respect to the n-th printing, stop pulse data is not generated and the canceling operation is not executed in other combinations of the printing commands of the printing data before and after the n-th printing.

Thus, according to the present embodiment, the execution / non-execution of the offset operation can be reliably switched between before and after the predetermined cycle timing and when there is no print command at the next cycle timing, and When the execution and non-execution of the offset operation are selectively switched, the control circuit 22 can accurately control the voltage application operation of the drive circuit 21 to the electrodes 619c of the ink chambers 613 of the print head 600. . Note that the switching between the execution and non-execution of the canceling operation, that is, the condition for adding the stop pulse is not limited to the above combination, and can be arbitrarily changed. In particular, according to the present invention, the content of the transfer data control signal PAT [7-0] is appropriately changed according to the temperature condition and the use condition of the device, and, similarly to the one described in JP-A-9-48112, A stop pulse signal can be added or omitted. This change of the logical operation expression can be dealt with by changing the logic circuit of the control circuit 22 or by storing a desired transfer data control signal pattern in the ROM 12 and the RAM 13. The transfer data control signal stored in the RAM 13 can be rewritten from an external device 26 such as a personal computer.

Further, according to the present embodiment, the ink ejection that can selectively switch between execution and non-execution of the offset operation by configuring the control circuit 22 as described above while the drive circuit 21 is the same as the conventional one. A device can be obtained. As described above, the drive circuit 21 composed of a one-chip IC constitutes a print head unit 508 together with the print head 600, and the print head unit 508 is attached to the carriage 504. It is connected to the drive circuit 21 via a cable 28. Therefore, by replacing only the control circuit 22 without changing the print head unit 508, the present embodiment can be realized, and the cost required for remodeling can be reduced.

Next, an ink ejecting apparatus according to a second embodiment of the present invention will be described with reference to the drawings.

FIG. 9 is a block diagram illustrating an electrical configuration of an ink jet printer including the ink ejecting apparatus according to the present embodiment. The basic configuration including a microcomputer 11, a control circuit 22, a drive circuit 21, and the like is the same as that of the above embodiment. Is the same as The main difference between the present embodiment and the first embodiment is that, in the present embodiment, the control circuit 22 is stored in the image memory 25 in accordance with the print timing signal TS and the control signal RS. When forming the print data on the recording medium based on the print data, the ejection pulse data FD for the ejection operation for ejecting the ink from the nozzle 618 of the print head 600 and the residual pressure wave vibration in the ink chamber 613 described above are used. Stop pulse data SD for canceling operation to cancel out, and a switching signal KS for switching each data FD and SD are generated and output to the drive circuit 21. The microcomputer 11 outputs to the control circuit 22 a transfer data control signal PAT [7-0] that can be changed as necessary to control the data FD and SD. The switching is performed by the drive circuit 21.

FIG. 10 is a block diagram showing the internal configuration of the drive circuit 21. In this embodiment, two serial-to-parallel converters 31A and 31B are provided. One serial-parallel converter 31A is constituted by a shift register having a length of 64 bits, receives the injection pulse data FD serially transferred from the control circuit 22 in synchronization with the transfer clock TCK, and receives the rising edge of the transfer clock TCK. Therefore, serial-parallel conversion of the ejection pulse data FD is performed by converting the ejection pulse data FD into the parallel data FPD0 to FPD63. The other serial-parallel converter 34 is composed of a shift register having a length of 64 bits, receives stop pulse data SD serially transferred from the control circuit 22 in synchronization with the transfer clock TCK, and receives the rising edge of the transfer clock TCK. Therefore, by converting the stop pulse data SD into the parallel data SPD0 to SPD63, serial-parallel conversion of the stop pulse data SD is performed.

Each of the 64 switching circuits 35 is switched to one of the nodes A and B according to the switching signal KS transferred from the control circuit 22, and when the switching is performed to the node A, the serial-parallel converter 33 The output (parallel data FPD0 to FPD63 of the ejection pulse data) is selected. When the output is switched to the node B, the output of the serial-parallel converter 34 (parallel data SPD0 to SPD63 of the stop pulse data) is selected and the selected one is selected. The output is output to the data latch 32. The configurations of the data latch 32, the AND gate 33, and the output circuit 34 are the same as those in the above embodiment.

FIG. 11 is a block diagram showing a main configuration inside the control circuit 22. The data setting circuit 41, the serial-parallel conversion circuit 42, the first shift register 43, the second shift register 44, the transfer data generation unit 45, and the controller circuit The basic configuration consisting of 47 is the same as that of the above embodiment. The difference from the above-described embodiment is that, in the present embodiment, the serial-parallel conversion circuit 42 outputs print data sequentially output from the serial output terminal OUT to the serial-parallel converter 31A of the drive circuit 21. (FD). Further, the first shift register 43 inputs the print data from its serial output terminal OUT to the transfer data generation unit 45 and the second shift register 44 without inputting it to its own serial input terminal IN2.

The transfer data generation unit 45 is based on the output (A, B, C) from the serial-parallel conversion circuit 42, the first shift register 43, and the second shift register 44, and the transfer data control signal PAT [7-0]. Generate stop pulse data (SD). The transfer data control signal PAT [7-0] may be input from the controller circuit 47 as in the above-described embodiment, but is input from the microcomputer 11 in the present embodiment. The internal configuration of the transfer data generation unit 45 is the same as that in FIG.

(4) The controller circuit 47 generates a switching signal KS in addition to the strobe signal STB, the transfer clock TCK and the print clock ICK, and outputs the same to the drive circuit 21 as in the above-described embodiment.

Next, the operation of the ink ejecting apparatus according to the second embodiment configured as described above will be described with reference to FIG. The print clock ICK and the strobe signal STB are the same as in the above embodiment.

In the present embodiment, in the printing cycle Tm-1, the ejection pulse data FDn for the n-th printing and the stop pulse data SDn-1 for the (n-1) -th printing are simultaneously transferred. Then, in the printing cycle Tm, the ejection pulse data FDn + 1 for the (n + 1) th printing and the stop pulse data SDn for the nth printing are simultaneously transferred.

In other words, in the printing cycle Tm-1, the printing clock ICK becomes n-th after the firing pulse clock ICKfn-1 corresponding to the firing pulse data FDn-1 (not shown) for the (n-1) th printing is transferred. The stop pulse clock ICKsn-1 corresponding to the stop pulse data SDn-1 for the first printing is transferred. Then, in the printing cycle Tm, the printing clock ICK corresponds to the stop pulse data SDn for the n-th printing after the firing pulse clock ICKfn corresponding to the firing pulse data FDn for the n-th printing is transferred. The stop pulse clock ICKsn is transferred.

(4) The switching signal KS is transferred corresponding to the strobe signal STB. In each of the printing cycles Tm-1, Tm, the switching signal KS causes each switching circuit 35 of the drive circuit 21 to transfer each strobe signal STBsn-1, STBsn corresponding to each of the stop pulse data SDn-1, SDn. Switch to the node B side, otherwise switch each switching circuit 35 to the node A side. Therefore, when each switching circuit 35 is switched to the node A side according to the switching signal KS, the data latch 32 outputs the output of the serial-parallel converter 31A (the parallel data FPD0 to FPD63 obtained by parallel-converting the ejection pulse data FD). ), And when each switching circuit 35 is switched to the node B side, the output of the serial-parallel converter 31B (each parallel data SPD0 to SPD63 obtained by parallel-converting the stop pulse data SD) is latched. Therefore, when the ejection pulse data FDn-1 (not shown) for the (n-1) th printing is latched in the data latch 32, the serial-parallel converter 34 supplies the data for the (n-1) th printing. , And the serial-parallel converter 33 stores the ejection pulse data FDn for the n-th printing. After the (n-1) th ejection pulse data FDn-1 is output, the corresponding stop pulse data SDn-1 is output, and then the n-th ejection pulse data FDn is output.

The data latched by the data latch 32 is output to the print head 600 in synchronization with the print clock ICK, and the ejection operation and the cancel operation are performed as in the above-described embodiment.

FIG. 7 is a time chart of the control circuit 22, which is similar to FIG. In this case, a time chart of a section in which the ejection pulse data FDn + 1 and the stop pulse data SDn are transferred as transfer data at the timing of the printing cycle Tm shown in FIG.

FIGS. 13 and 14 show a third embodiment. This embodiment is a slightly modified version of the second embodiment, in which two data latches 32A and 32B are provided corresponding to two serial-parallel converters 31A and 31B, and a switching circuit 35 is provided. One of the two data latches 32A and 32B is selectively output to the AND gate 33.

FIG. 14 is a time chart of the print clock ICK, the strobe signal STB, the ejection pulse data FD, the stop pulse data SD, and the switching signal KS in the third embodiment. In the printing cycle Tm-1, the ejection pulse data FDn for the n-th printing and the stop pulse data SDn for the n-th printing are simultaneously transferred. Then, in the printing cycle Tm, the ejection pulse data FDn + 1 for the (n + 1) th printing and the stop pulse data SDn + 1 for the (n + 1) th printing are simultaneously transferred. In this embodiment, the ejection pulse data FDn is an output (B) of the first shift register 43 of the control circuit 22 as shown by a broken line in FIG.

In the printing cycle Tm-1, the strobe signal STB is a strobe signal STBn corresponding to the ejection pulse data FDn-1 (not shown) and the stop pulse data SDn-1 (not shown) for the (n-1) th printing. -1 is transferred. In the printing cycle Tm, the strobe signal STB is a strobe signal STBn corresponding to the ejection pulse data FDn and the stop pulse data SDn for the n-th printing. Further, the switching signal KS is transferred corresponding to the print clock ICK.

In each printing cycle Tm-1, Tm, each switching circuit 35 of the drive circuit 21 switches the switching signal KS when the respective stop pulse clocks ICKsn-1, ICKsn corresponding to the respective stop pulse data SDn-1, SDn are transferred. Is switched to the node B side, and at other times, it is switched to the node A side according to the switching signal KS. When each switching circuit 35 is switched to the node A side, the output of the serial-parallel converter 31A latched by the data latch 32A (in which the injection pulse data FD is parallel-converted) is supplied to each AND gate 33 of the drive circuit 21. Each of the parallel data FPD0 to FPD63) is input. Further, when each switching circuit 35 is switched to the node B side, each AND gate 33 outputs the output of the serial-parallel converter 31B latched by the data latch 32B (each parallel-converted stop-pulse data SD). Data SPD0 to SPD63) are input.

Therefore, the data latched by the data latches 32A and 32B is output to the print head 600 in synchronization with the print clock ICK, and the ejection operation and the cancel operation are performed as in the above-described embodiment. The time chart of the section in which the injection pulse data FDn and the stop pulse data SDn are transferred is the same as that described above, and the description is omitted.

As described above, in the control circuit 22 of the present embodiment, the ejection pulse data FDn for the n-th printing and the stop pulse data SDn for the n-th printing are simultaneously generated. The data FDn and SDn are simultaneously transferred to the drive circuit 21, and the serial-parallel converters 31A and 31B simultaneously generate parallel data FPD0 to FPD63 and SPD0 to SPD63 obtained by serial-parallel-converting the data FDn and SDn. You. The parallel data FPD0 to FPD63 and SPD0 to SPD63 are output to the data latches 32A and 32B, respectively, and are simultaneously latched according to the strobe signal STB. Then, each of the parallel data FPD0 to FPD63, SPD0 to SPD63 once latched in each of the data latches 32A and 32B by each of the switching circuits 35 switched according to the switching signal KS corresponding to the print clock ICK is ANDed. The driving data A0 to A63 are output to the gate 33 and generated in accordance with the print clock ICK.

Therefore, as shown in FIG. 14, the time interval between the timing t5 at which the stop pulse clock ICKsn-1 corresponding to the stop pulse data SDn-1 falls and the timing t1 at which the injection pulse clock ICKfn corresponding to the injection pulse data FDn rises Can be shortened. Further, the time interval between the timing t2 at which the ejection pulse clock ICKfn corresponding to the ejection pulse data FDn falls and the timing t3 at which the stop pulse clock ICKsn corresponding to the stop pulse data SDn rises can be shortened. Therefore, according to the present embodiment, it is possible to further shorten the timing of each printing cycle Tm-1, Tm as compared with the second embodiment, and it is possible to improve the printing speed more favorably.

FIG. 15 is a block diagram showing an electrical configuration of an ink jet printer provided with an ink ejecting apparatus according to the fourth embodiment. The basic configuration including a microcomputer 11, a control circuit 22, a drive circuit 21, and the like is the same as that of the first embodiment. This is the same as the first embodiment. The main difference between the present embodiment and the first embodiment is that, in the present embodiment, an additional pulse for the canceling operation is generated by the control circuit 22 and transferred to the drive circuit 21. Instead, the control circuit 22 generates a switching signal for switching the combination of print data from the control circuit 22 instead of the transfer data control signal that determines the condition for performing the canceling operation. Is to be output.

That is, in FIG. 15, the difference from FIG. 2 is that the switching signal KS (combination instruction signal) for switching the combination of print data as a condition for adding a canceling operation from the control circuit 22 to the drive circuit 21. Output. The generation of the additional pulse for the canceling operation is performed by the drive circuit 21 as described below in detail. Others are the same as those described above, and description thereof will be omitted.

FIG. 16 is a block diagram showing the internal configuration of the drive circuit 21. The drive circuit 21 includes an AND gate 33, an output circuit 34, a data latch 32, three serial-parallel converters 31A, 31B, 31C, and 64 pulse data generation circuits 36.

The first serial-parallel converter 31A is constituted by a shift register having a length of 64 bits, receives transfer data DATA serially transferred in synchronization with the transfer clock TCK from the control circuit 22, and receives the rising edge of the transfer clock TCK. By converting the transfer data DATA into parallel data, serial-parallel conversion of the transfer data DATA is performed. The second serial-to-parallel converter 31B is composed of a 64-bit shift register, and sequentially transfers the transfer data DATA input from the first serial-to-parallel converter 31A from the leading data in accordance with the rise of the transfer clock TCK. Serial output bit by bit. The third serial-to-parallel converter 31C is composed of a shift register having a length of 64 bits, and serially inputs the transfer data DATA serially output from the second serial-to-parallel converter 31B according to the rise of the transfer clock TCK. By converting data DATA into parallel data, serial-parallel conversion of transfer data DATA is performed.

The 64 pulse data generating circuits 36 are composed of logic circuits and function as additional pulse data generating means, and each of the serial-parallel converters 31A according to the switching signal KS transferred from the control circuit 22. By performing a logical operation from the outputs (each parallel data) of .about.31C, injection pulse data for the injection operation and stop pulse data for the offset operation are generated. The switching signal is a condition for generating a stop pulse, that is, a signal for instructing a combination of data before and after a print pulse, and may be appropriately determined according to a temperature condition and a use condition.

The data latch 32 latches each stop pulse data or each ejection pulse data in accordance with the rise of the strobe signal STB transferred from the control circuit 22, and outputs each latched data to each AND gate 33. Each of the 64 AND gates 33 calculates the logical product of each stop pulse data or each ejection pulse data and the print clock ICK transferred from the control circuit 22, and calculates each stop pulse data or each ejection pulse data. Each drive data as a result of the logical product is generated.

Each of the # 64 output circuits 34 generates a drive signal suitable for the print head based on each drive data, and outputs each drive signal to the electrode 619 of each ink chamber 613 of the print head 600.

By the way, each parallel data output from each of the serial-parallel converters 31A to 31C corresponds to each ink chamber 613 of the print head 600.
Therefore, each stop pulse data or each ejection pulse data output from each pulse data generation circuit 36 also corresponds to each ink chamber 613 of the print head 600.

(5) The internal configuration of each pulse data generation circuit 36 is the same as that in FIG. A switching signal KS having an equivalent function is input to the pulse data generation circuit 36 instead of the transfer data control signal as a signal for instructing a combination of print data for determining a condition for executing the canceling operation. . The AND circuit of FIG. 5 inputs the data corresponding to the same ink chamber 613 among the parallel data output from the serial-parallel converters 31A to 31C, respectively, and as in the first embodiment, And a switching signal KS (this is indicated by PAT [7-0]). The output terminal of the OR circuit outputs stop pulse data and ejection pulse data. That is, each pulse data generation circuit 36 outputs each stop pulse data or each ejection pulse data according to the switching signal KS. The switching signal PAT [7-0] outputs an arbitrary one of the data A, B, and C by appropriately selecting the respective contents as in the first embodiment, and outputs the data A, A signal based on any combination of B and C can be output.

Next, the operation of the ink ejecting apparatus according to the fourth embodiment configured as described above will be described. FIG. 17 is a time chart of the print clock ICK, the strobe signal STB, the transfer data DATA, and the switching signal PAT [7-0]. The transfer data DATA is transferred at each timing of a predetermined printing cycle. The stop pulse data and the ejection pulse data generated by each generation circuit 36 are transferred at predetermined print cycle timings in accordance with the strobe signal STB and the print clock ICK, respectively.

(4) At the timing of each printing cycle, the transfer data DATA is serially transferred between the serial-parallel converters 31A to 31C according to the rise of the transfer clock, and is shifted one bit at a time in each serial-parallel converter. That is, assuming that after the transfer of the transfer data of one printing cycle, each parallel data output from the second serial-parallel converter 31B is the ejection pulse data for the n-th printing, the first serial-parallel Each parallel data output from the converter 31A is ejection pulse data for the (n + 1) th printing, and each parallel data output from the third serial-parallel converter 31C is an ejection pulse data for the (n-1) th printing. Data. The switching signal PAT [7-0] is transferred in response to the strobe signal. Then, in one printing cycle, after the ejection pulse clock ICKf corresponding to the ejection pulse data for printing one dot is transferred, the printing clock is a stop clock corresponding to the stop pulse data for printing the dot. The pulse clock ICKs is transferred. As the strobe signal, STBf for the ejection pulse data and STBs for the stop pulse data are successively transferred.

The pulse data generation circuit 36 receives the three outputs A, B, and C and the switching signal PAT [7-0], and performs a logical operation. By setting the switching control signal PAT [7-0] = [1,1,1,1,0,0,0,0] and setting PAT7,6,5,4 to “1”, the state of B and C Irrespective of the above, the data corresponding to A, that is, the same data stored in the first serial-parallel converter 31A is output from one of the PATs 7, 6, 5, and 4 as ejection pulse data from the OR circuit. Is done. After the strobe signal STBf corresponding to the ejection pulse rises and the ejection pulse data is latched in the data latch 32, the contents of the first to third serial-parallel converters 31A to 31C are shifted, and the contents of the previous A are changed to B and B, respectively. Is changed to C and the new transfer data is changed to A, the switching control signal PAT [7-0] = [0,0,0,0,1,0,0,0] and only PAT3 is set to "1". Thus, only when A = 0, B = 1, and C = 1, “1” is output from the AND gate corresponding to PAT3. In other words, the transfer data DATA (D) becomes "1" with respect to the dot (B) having an ejection dot before (C) and no ejection dot after (A), and a stop pulse can be added. The stop pulse data synthesized by the pulse data generation circuit 36 is latched by the data latch 32 at the rise of the strobe signal STBs.

Each AND gate 33 of the drive circuit 21 outputs a drive signal to the print head 600 according to the state of the data latch 32 and the print clock ICK, as in the above embodiment.

According to the present embodiment, an ink ejecting apparatus capable of selectively switching between execution and non-execution of a canceling operation by configuring only the driving circuit 21 as described above while keeping the control circuit 22 as it is in the related art. Obtainable.

FIG. 18 shows a fifth embodiment, which is a slightly modified version of the fourth embodiment. In the present embodiment, three data latches 32A, 32B, 32C are provided corresponding to the three serial-parallel converters 31A, 31B, 31C. Each of the data latches 32A, 32B, and 32C latches each parallel data output of each of the serial-parallel converters 31A, 31B, and 31C according to the rise of the strobe signal (STB) transferred from the control circuit 22. Each of the 64 pulse data generation circuits 36 obtains the logical product of the switching signal KS transferred from the control circuit 22 and each parallel data output of each of the data latches 32A, 32B, 32C, and performs the injection for the injection operation. The pulse data and the stop pulse data for the cancel operation are generated and output to the AND gate 33. The pulse data generation circuit 36 is the same as that shown in FIG.

Hereinafter, the operation of the drive circuit 21 will be described with reference to FIG.

Each of the serial-parallel converters 31A to 31C performs the same operation as in the above-described embodiment, and the data latches 32A to 32C output the print data output from the serial-parallel converters 31A to 31C at the rising edge of the strobe signal. Latch. Each pulse data generation circuit 36 sets the switching signal to PAT [7-0] = [1,1,0,0,1,1,0,0] so that the data corresponding to B becomes ejection pulse data. Is output. The AND gate 33 performs a logical operation on the ejection pulse clock of the print clock ICK and outputs the result to the print head 600.

Subsequently, the switching signal is switched to PAT [7-0] = [0,0,0,0,1,0,0,0] while the contents of the data latches 32A to 32C are maintained as they are, and the above embodiment is described. By setting only PAT3 to “1” in the same manner as in the above, “1” is output from the AND gate corresponding to PAT3 only when A = 0, B = 1, and C = 1. The AND gate 33 performs a logical operation on the stop pulse clock of the print clock ICK and outputs the result to the print head 600.

As described above, according to the ink jet apparatus of the fifth embodiment, each parallel data output from the serial-parallel converters 31A to 31C is temporarily latched by the data latches 32A to 32C. Then, in accordance with a switching signal corresponding to the print clock, the pulse data generation circuit 36 switches between the ejection pulse data and the stop pulse data to be sent to the AND circuit 31. Therefore, the time interval between the timing at which the stop pulse falls and the timing at which the ejection pulse rises in the print clock ICK, and the time interval between the timing at which the ejection pulse falls and the timing at which the stop pulse rises can be shortened. The timing of each printing cycle can be made shorter than in the fourth embodiment, and the printing speed can be improved more favorably.

Next, a sixth embodiment of the present invention will be described. The schematic electrical configuration of the ink jet printer of the sixth embodiment is the same as that of FIG. 2, and the drive circuit 21 is the same as that of FIG.

FIG. 20 shows a main configuration inside the control circuit 22 (gate array). The control circuit 22 receives a serial output from the first register 52, the second register 53, and the third register 54, which form three data storage units, and receives a stop pulse (SP) for canceling operation. A) an SP data generating section 56 (additional pulse data generating means) for generating data, a data transfer section 55, and a controller circuit 57. The print data stored in the print data area 25a of the image memory 25 is sequentially read out by the registers 52 to 54 in units of one byte in the print direction, and the print data n (B), The third register 54 receives the print data n-1 (C), and the first register 52 receives the print data n + 1 (A). Here, the print data n is data of the one dot at a predetermined timing, the print data n + 1 is ejection data immediately after the one dot, and the print data n-1 is ejection data immediately before the one dot. . Each of the registers 52, 53, and 54 outputs (A, B, and C) the print data to the SP data generation unit 56 according to the register control signal.

The SP data generation unit 56 has the same configuration as that of FIG. 5 of the first embodiment, is composed of a logic circuit, and has print data n (B) from the second register 53 and print data from the third register 54. n-1 (C) and print data n + 1 (A) from the first register 52 are taken in, logically operated together with the SP data control signal PAT [7-0] from the controller unit 57, and the stop pulse (SP) is generated. Generate. The SP data n (D) generated by the SP data generator 56 is stored in the SP data area 25b of the image memory 25.

The data transfer unit 55 alternately reads the print data stored in the print data area 25a of the image memory 25 and the SP data stored in the SP data area 25b, and serially outputs the transfer data DATA. The transfer data DATA includes ejection pulse data for an ejection operation for ejecting ink from the nozzles 618 of the print head 600, and stop pulse data for an offset operation for canceling the residual pressure wave vibration in the ink chamber 613. It is. Further, the controller circuit 57 controls the registers 52 to 54, the SP data generation unit 56, the data transfer unit 55, and the image memory 25 according to the print timing signal TS and the control signal RS transferred from the microcomputer 11. It generates a register control signal, an SP data control signal, a data transfer control signal, and a memory address signal, and generates a transfer data control signal, a strobe signal STB synchronized with the transfer data DATA, a transfer clock TCK, and a print clock ICK.

Next, an operation of the ink ejecting apparatus according to the sixth embodiment configured as described above will be described. The time charts of the print clock ICK, the strobe signal STB, and the transfer data DATA are the same as those in FIG. 6 of the first embodiment, and a description thereof will be omitted.
FIG. 21 shows an example of an image map of the print data area 25a of the image memory 25, and FIG. 22 shows an example of an image map of the SP data area 25b of the image memory 25. In the figure, black indicates ejection dots, and white indicates no ejection dots. Eight columns (0 to 7) of print data are simultaneously processed in byte units. A case will be described in which the immediately preceding dot data n-1 (C) and the immediately succeeding dot data n + 1 (A) are used for one byte of print dot data n (B) in the vertical direction.

Now, the SP data control signal PAT [7-0] is set to [0,0,0,0,1,0,0,0].
By setting only PAT3 to “1”, “1” is output from the AND gate corresponding to PAT3 only when A = 0, B = 1, and C = 1. In other words, stop pulse data (SP data) to be added is created for a dot (B) having an ejection dot immediately before (C) and no ejection dot immediately after (A), and is stored in the SP data area 25b. . Otherwise, no stop pulse data is stored in the same area. The SP data created in the case of the print data in FIG. 21 is as shown in FIG. The data transfer unit 55 reads the print data and the SP data from the image memory 25 based on the data transfer control signal, and outputs the read data and the SP data to the drive circuit 21 as transfer data DATA.

As shown in FIGS. 3 and 6 of the first embodiment, the drive circuit 21 inputs print data to the serial-parallel converter 31 for the number of ink chambers of the print head in accordance with the transfer clock TCK, and outputs a strobe signal STB. In accordance with the above, the data is latched by the data latch 32, the logical product is taken with the print clock ICK, and the result is output to the print head. Similarly, stop pulse (SP) data is input and output to the print head.

As described above, according to the sixth embodiment, the drive circuit 21 is not changed from the conventional one, and only the control circuit 22 is configured as described above to selectively switch between execution and non-execution of the cancel operation. Can be obtained.

The present invention is not limited to the above embodiments, and various modifications are possible as follows.

(1) In the above embodiments, only one print pulse corresponding to the ejection pulse data is generated at each print cycle timing, but a plurality of print pulses may be generated. In this case, the number of print pulses corresponding to the ejection pulse data is equal to the number of ink droplets ejected from the nozzle 618. Therefore, as the number of printing pulses corresponding to the ejection pulse data is increased, the number of ink droplets to be ejected is also increased, and the printing density is increased, so that a thick and clear image can be obtained.

(2) In each of the above embodiments, the width of the ejection pulse clock in the print clock corresponding to the ejection pulse data is set to be the same as the one-way propagation time T, but is set to be approximately an odd multiple of the one-way propagation time T. Is also good.

(3) In the above embodiments, the width of the stop pulse clock in the print clock corresponding to the stop pulse data is set to 0.5 times the one-way propagation time T, but ink is ejected from the nozzle 618 by the print clock. Any value may be set as long as the pulse width is not set and the pulse width ensures that the canceling operation is executed.

(4) In each of the above embodiments, the time from the falling timing of the ejection pulse clock to the intermediate timing between the rising timing and the falling timing of the stop pulse clock is set to 2.5 times the one-way propagation time T. However, any value may be set as long as the canceling operation is performed reliably.

(5) In the above embodiments, the voltage of the drive signal generated by the output circuit 34 is the same in the ink ejection operation and the offset operation, but the voltage of the drive signal generated by the output circuit 34 in the offset operation is The voltage may be lower than that in the ink ejection operation, or may be a negative voltage. Further, in each of the above embodiments, the ink is ejected by changing the volume of the ink chamber 613 by the piezoelectric deformation of the lower wall 607 and the upper wall 605 of the actuator wall 603, but one of the lower wall 607 and the upper wall 605. May be formed from a material that does not undergo piezoelectric deformation, and the other may be deformed in conjunction with the piezoelectric deformation to eject ink. In each of the above embodiments, the air chambers 615 are provided on both sides of the ink chambers 613. However, the air chambers 613 may not be provided, and the ink chambers 613 may be adjacent to each other.

(6) In the above embodiments, the print head 600 is applied to a printer in which the print head 600 reciprocates together with the carriage 504, but may be applied to a so-called line printer in which the print head 600 is fixed to the printer body.

(7) In each of the above embodiments, the present invention is applied to a printer which receives data from a personal computer and performs a printing operation. However, the present invention may be applied to a word processor or a facsimile in which an ink droplet ejecting device is incorporated as a printing mechanism.

FIG. 1 is a perspective view illustrating a schematic configuration of an inkjet printer including an ink ejecting apparatus according to an embodiment. FIG. 1 is a block diagram illustrating an electrical configuration of an inkjet printer including an ink ejecting apparatus according to a first embodiment of the present invention. FIG. 3 is a block diagram showing a configuration of a drive circuit 21 in FIG. 2. FIG. 3 is a block diagram illustrating a configuration of a control circuit 22 in FIG. 2. FIG. 5 is a circuit diagram of a transfer data generation unit 45 in FIG. 4. 5 is a time chart for explaining the operation of the ink ejection device of the present embodiment. 5 is a time chart for explaining the operation of the ink ejection device of the present embodiment. 5 is a time chart for explaining the operation of the ink ejection device of the present embodiment. FIG. 9 is a block diagram illustrating an electrical configuration of an inkjet printer including the ink ejecting apparatus according to the second embodiment. FIG. 10 is a block diagram showing a configuration of the drive circuit 21 in FIG. 9. FIG. 10 is a block diagram showing a configuration of a control circuit 22 in FIG. 9. 9 is a time chart for explaining the operation of the ink ejection device according to the second embodiment. FIG. 9 is a block diagram illustrating a configuration of a drive circuit of an ink ejection device according to a third embodiment. 9 is a time chart for explaining the operation of the ink ejecting apparatus according to the third embodiment. FIG. 13 is a block diagram illustrating an electrical configuration of an inkjet printer including an ink ejecting apparatus according to a fourth embodiment. FIG. 17 is a block diagram showing the configuration of the drive circuit 21 of FIG. 9 is a time chart for explaining the operation of the ink ejection device according to the fourth embodiment. FIG. 13 is a block diagram illustrating a configuration of a drive circuit of an ink ejecting apparatus according to a fifth embodiment. 13 is a time chart for explaining the operation of the ink ejection device according to the fifth embodiment. FIG. 13 is a block diagram illustrating a configuration of a control circuit 22 according to a sixth embodiment. FIG. 14 is a diagram illustrating an image map of a print data area of an image memory according to a sixth embodiment. FIG. 18 is a diagram illustrating an image map of an SP data area of an image memory according to a sixth embodiment. FIG. 25 is a cross-sectional view showing a configuration of a print head of the ink ejecting apparatus according to the conventional embodiment and the embodiment of the present invention, and is a cross-sectional view taken along line XX of FIG. 24. FIG. 24 is a sectional view taken along line YY of FIG. 23. FIG. 24 is a sectional view for explaining the operation of the print head of FIG. 23.

Explanation of reference numerals

613: Ink chamber 603: Actuator wall 21: Drive circuit 22: Control circuit 25: Image memory 31, 31A, 31B, 31C: Serial-parallel converter (storage means)
36 ... Pulse data generation circuit (transfer data generation means)
42 ... Serial-parallel converter (storage means)
43, 44... Shift registers (storage means)
45 transfer data generation unit (transfer data generation means)
52, 53, 54 ... register (storage means)
56: SP data generation unit (transfer data generation means)

Claims (8)

A print head having an ink chamber filled with ink and an actuator for ejecting ink from the ink chamber,
A plurality of storage means for respectively storing the print data supplied before and after corresponding to one of the actuators;
An ink droplet ejecting apparatus comprising: transfer data generating means for generating a data signal for driving the actuator based on print data output from each of the plurality of storage means and the temperature of the apparatus. Further, a means for generating a plurality of pulse clocks corresponding to each printing cycle is provided,
2. The ink droplet ejection device according to claim 1, wherein the plurality of pulse clocks are selectively output to the actuator based on the data signal generated by the transfer data generation unit, and the actuator is driven. A print head having an ink chamber filled with ink and an actuator for ejecting ink from the ink chamber,
Means for outputting a plurality of pulse clocks corresponding to each printing cycle;
A plurality of storage means for respectively storing the print data supplied before and after corresponding to one of the actuators;
An ink droplet ejecting apparatus comprising: a circuit for selectively outputting the plurality of pulse clocks to the actuator based on print data output from each of the plurality of storage units and the temperature of the apparatus. A circuit that selectively outputs the pulse clock, a transfer data generating unit that outputs a data signal corresponding to the plurality of pulse clocks based on the logical operation, and selects the plurality of pulse clocks based on the data signal 4. The ink droplet ejecting apparatus according to claim 3, further comprising a gate circuit for outputting to the actuator. (5) The ink droplet ejecting apparatus according to any one of (1) to (4), wherein the storage unit includes three storage units for storing predetermined print data, print data immediately before the print data, and print data immediately after the print data. The data signal includes additional pulse data added to the ejection pulse data,
The ejection pulse data and the additional pulse data are serially input and subjected to parallel conversion corresponding to the ink chambers, and a plurality of pulse clocks corresponding to each of the printing cycles are selectively selected by the ejection pulse data and the additional pulse data. The ink droplet ejecting apparatus according to claim 2, further comprising a driving circuit that outputs to the actuator. The data signal includes additional pulse data added to the ejection pulse data,
A circuit for parallel-converting the ejection pulse data and the additional pulse data respectively corresponding to the ink chambers, a switching circuit for selectively outputting the ejection pulse data and the additional pulse data, and the switching circuit output from the switching circuit. The ink droplet ejection according to claim 2, further comprising a driving circuit including a gate circuit that selectively outputs a plurality of pulse clocks corresponding to each of the printing cycles to the actuator using ejection pulse data and additional pulse data. apparatus. The plurality of storage units store the serially transferred print data, respectively, and perform parallel conversion,
The circuit for selectively outputting the plurality of pulse clocks includes ejection pulse data based on the print data based on print data output from each of the plurality of storage units and the temperature of the apparatus, and the ejection data for the ejection data. 4. An additional pulse data to be added to the actuator is generated, and a plurality of pulse clocks corresponding to each printing cycle are selectively output to the actuator by the ejection pulse data and the additional pulse data. The ink droplet ejecting apparatus according to claim 1.

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