JP2011020458A - Capacitive load driving circuit, jetting apparatus, and printing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet printer capable of decreasing consumption of electric power. <P>SOLUTION: A charge origin electric potential preliminary adjustment waveform signal WCCOM for preliminarily adjusting an electric potential of a charge origin to a driving signal generating circuit 72 is formed, and a modulation signal CPWM for a charge origin electric potential pulse-modulated, is amplified in electric power by a pair of transistors 32 for a charge origin electric potential push-pull connected of a digital electric power amplifier 28 for the charge origin electric potential, and it is smoothed to output it to a collector of a transistor Tr1 for charging of the driving signal generating circuit 72. At the same time, a discharge origin electric potential preliminary adjustment waveform signal WDCOM for preliminarily adjusting an electric potential of a discharge origin from the driving signal generating circuit 72 is formed, and a modulation signal DPWM for a discharge origin electric potential pulse-modulated, is amplified in electric power by a pair of transistors 33 for discharge origin electric potential push-pull connected of a digital electric power amplifier 29 for the discharge origin electric potential, and it is smoothed to output it to a collector of a transistor Tr2 for discharging of the driving signal generating circuit 72. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  In the present invention, for example, a liquid discharge is made such that predetermined characters and images are drawn by discharging fine liquid droplets of a plurality of colors from a plurality of nozzles and forming fine particles (dots) on a print medium. It relates to the device.

Ink jet printers, which are examples of such liquid ejection devices, are generally inexpensive and can easily obtain high-quality color prints. Therefore, with the widespread use of personal computers and digital cameras, not only offices but also general users. It has become widespread.
In general, such an ink jet printer is configured such that a moving body called a carriage in which an ink cartridge and a print head are integrally provided reciprocates on a print medium in a direction intersecting the transport direction. By ejecting liquid ink droplets from the nozzles to form minute ink dots on the printing medium, a desired printed matter is created by drawing predetermined characters and images on the printing medium. The carriage is equipped with four color (yellow, magenta, cyan) ink cartridges including black (black) and a print head for each color, so that not only monochrome printing but also full-color printing combining each color is easy. (Furthermore, 6 colors, 7 colors, or 8 colors in which light cyan, light magenta, etc. are added to these colors are also put into practical use).

  Further, in this type of ink jet printer in which printing is executed while reciprocating the ink jet head on the carriage in a direction intersecting with the conveyance direction of the print medium, the ink jet head is set to 10 to cleanly print the entire page. It is necessary to reciprocate several times to several tens of times. In contrast, in an inkjet printer of a type in which a long inkjet head (not necessarily integrated) having the same dimensions as the width of the print medium is disposed and the carriage is not used, the inkjet head is moved in the width direction of the print medium. There is no need, and so-called one-pass printing is possible. The former inkjet printer is generally referred to as a “multi-pass (serial) inkjet printer”, and the latter inkjet printer is generally referred to as a “line head inkjet printer”.

  By the way, in this type of ink jet printer, higher gradation is required. The gradation is a state of density of each color included in a so-called pixel represented by ink dots, and the size of the ink dot corresponding to the color density of each pixel is called gradation, and can be expressed by ink dots. The number of furniture is called the number of gradations. High gradation means that the number of gradations is large. In order to change the gradation, for example, it is necessary to change the drive pulse to the actuator provided in the inkjet head. For example, when the actuator is a piezoelectric element, the displacement (distortion) of the piezoelectric element (exactly the diaphragm) increases as the voltage value applied to the piezoelectric element increases. The gradation can be changed.

  Therefore, in Patent Document 1 listed below, for example, a drive signal is generated by combining and connecting a plurality of drive pulses having different voltage peak values, and this is common to the piezoelectric elements of the same color nozzle provided in the inkjet head. From this drive signal, a drive pulse corresponding to the gradation of the ink dot to be formed is selected for each nozzle, and the selected drive pulse is supplied to the piezoelectric element of the corresponding nozzle to generate an ink droplet. The required gradation of ink dots is achieved by ejecting the ink.

A method of generating a drive signal (or drive pulse) is described in FIG. That is, the data is read from the memory in which the drive signal data is stored,
The analog data is converted by the / A converter, and the drive signal is supplied to the inkjet head through the current amplifier. Since the piezoelectric element is a charge / discharge actuator, the drive signal charges the charge / discharge actuator or discharges the charge from the charge / discharge actuator. As shown in FIG. 3, the circuit configuration of the current amplifier is composed of a charge transistor and a discharge transistor that are push-pull connected, and a drive signal is amplified by so-called linear drive using a high power supply potential. However, in the current amplifier having such a configuration, the potential difference between the power supply potential and the drive signal for charging the charge / discharge actuator and the potential difference between the drive signal discharged from the actuator and the ground potential are large, resulting in large power consumption. Since most of this power consumption is consumed as heat, a large transistor or a heat sink is required. In particular, the size of the heat sink is a major obstacle in layout.

  In order to overcome this drawback, in the ink jet printer described in Patent Document 3 below, a charging source potential adjusting transistor is interposed between a power source and a charging transistor, and the charging source potential adjusting transistor is used for adjustment. The charged source potential is supplied to the collector of the charging transistor via a smoothing filter, or a ground destination (discharge destination) potential adjusting transistor is interposed between the ground destination (discharge destination) and the discharge transistor. Then, by supplying the ground destination (discharge destination) potential adjusted by the ground destination (discharge destination) potential adjusting transistor to the collector of the discharge transistor through the smoothing filter, the charging source potential and the actuator are supplied. By reducing the potential difference between the drive signal to be charged or the ground destination (discharge destination) potential and the drive signal discharged from the actuator, the power consumption can be reduced. We are trying to decrease.

Japanese Patent Laid-Open No. 10-81013 JP 2004-306434 A JP 2006-272907 A

  However, in the inkjet printer described in Patent Document 3, a charging source potential adjusting transistor is interposed between the power source and the charging transistor, or between the ground destination (discharge destination) and the discharging transistor. Since only a ground destination (discharge destination) potential adjustment transistor is interposed between the charge source potential preliminary adjustment signal potential supplied to the charge transistor and the ground destination (discharge destination) supplied to the discharge transistor. ) The potential of the potential pre-adjustment signal cannot be made sufficiently close to the charge potential or discharge potential of the charge / discharge actuator. As a result, the potential difference between the charge source pre-adjustment signal and the drive signal for charging the actuator or the ground destination ( Discharge destination) The potential difference between the potential preliminary adjustment signal and the drive signal discharged from the actuator is not reduced, and the power consumption is sufficiently reduced. There is a problem that can not be.

  The present invention can reduce the potential difference between the charge source potential preliminary adjustment signal and the drive signal charged to the charge / discharge actuator or the potential difference between the discharge destination potential preliminary adjustment signal and the drive signal discharged from the charge / discharge actuator, An object of the present invention is to provide a liquid ejection device capable of reducing power consumption.

In order to solve the above problems, a liquid discharge apparatus according to the present invention includes a plurality of nozzles provided in a liquid discharge head, a charge / discharge actuator provided corresponding to each nozzle, and a nozzle to discharge liquid. In a liquid ejecting apparatus including a driving unit that applies a driving signal to a charge / discharge actuator, a driving waveform signal generating unit that generates a driving waveform signal serving as a reference of a signal for controlling the driving state of the actuator, and a push-pull connection Drive signal generation means for amplifying the drive waveform signal generated by the drive waveform signal generation means by the charged transistor and the discharge transistor and outputting a drive signal; and a potential of the charge source to the drive signal generation means Charge source potential preliminary adjustment waveform signal generating means for generating a charge source potential preliminary adjustment waveform signal for preliminary adjustment, and the drive signal generation means The charge source to the drive signal generating means is disposed between the charge source and the drive signal generating means and is generated by the charge source potential preliminary adjustment waveform signal generating means. Charging source potential preliminary adjustment means for preliminarily adjusting the potential, wherein the charging source potential preliminary adjustment means performs pulse modulation on the charging source potential preliminary adjustment waveform signal generated by the charging source potential preliminary adjustment waveform signal generation means. An original potential modulation means, and a charge source potential digital power amplifier that amplifies the charge source potential modulation signal pulse-modulated by the charge source potential modulation means by a push-pull connected charge source potential transistor pair; Charging for outputting the charging source potential preliminary adjustment signal amplified by the charging source potential digital power amplifier to the collector of the charging transistor of the drive signal generating means It is characterized in that a potential smoothing filter.

According to the liquid ejection device of the present invention, the potential difference between the charge source potential preliminary adjustment signal and the drive signal for charging the charge / discharge actuator can be reduced, and the power consumption can be reduced.
Further, in the liquid discharge apparatus of the present invention, the charging source potential preliminary adjustment waveform signal generating means is a charge for adjusting the potential of the charging source potential preliminary adjustment signal by adjusting the voltage value of the charging source potential preliminary adjustment signal. An original potential preliminary adjustment waveform signal is generated.

According to the liquid ejection apparatus of the present invention, it is possible to improve the accuracy of the drive signal and further reduce the power consumption.
Further, in the liquid ejection apparatus of the present invention, the charging source potential preliminary adjustment waveform signal generation unit adjusts the phase of the charging source potential preliminary adjustment signal to adjust the potential of the charging source potential preliminary adjustment signal. A potential pre-adjustment waveform signal is generated.

According to the liquid ejection apparatus of the present invention, it is possible to improve the accuracy of the drive signal and further reduce the power consumption.
The liquid ejection device of the present invention is driven by a plurality of nozzles provided in the liquid ejection head, a charge / discharge actuator provided corresponding to each nozzle, and a charge / discharge actuator of the nozzle that should eject the liquid. In a liquid ejection apparatus including a driving unit that applies a signal, a driving waveform signal generating unit that generates a driving waveform signal serving as a reference of a signal that controls a driving state of the actuator, a push-pull-connected charging transistor, Drive signal generating means for amplifying the drive waveform signal generated by the drive waveform signal generating means by a discharge transistor and outputting a drive signal; and a discharge destination for preliminarily adjusting the potential of the discharge destination of the drive signal generating means Discharge destination potential pre-adjustment waveform signal generating means for generating a potential pre-adjustment waveform signal, a discharge destination from the drive signal generating means and the drive Discharge disposed between the signal generating means and the discharge destination potential preliminary adjustment waveform signal generated by the discharge destination potential preliminary adjustment waveform signal generation means based on the discharge destination potential preliminary adjustment waveform signal. Pre-potential pre-adjusting means, wherein the pre-discharge destination potential pre-adjusting means pulse-modulates discharge destination potential pre-adjusted waveform signal generated by the discharge destination pre-potential adjustment waveform signal generating means; A discharge destination potential digital power amplifier that amplifies the power of the modulation signal for the discharge destination potential pulse-modulated by the discharge destination potential modulation means by the push-pull connected discharge destination potential transistor pair, and the discharge destination potential digital A smoothing fill for the discharge destination potential for outputting the discharge destination potential preliminary adjustment signal amplified by the power amplifier to the collector of the discharge transistor of the drive signal generating means It is characterized in that it comprises and.

According to the liquid ejection apparatus of the present invention, the potential difference between the discharge destination potential preliminary adjustment signal and the drive signal discharged from the charge / discharge actuator can be reduced, and the power consumption can be reduced.
Further, in the liquid discharge apparatus of the present invention, the discharge destination potential preliminary adjustment waveform signal generating means adjusts the voltage value of the discharge destination potential preliminary adjustment signal to adjust the potential of the discharge destination potential preliminary adjustment signal. A pre-potential pre-adjustment waveform signal is generated.

According to the liquid ejection apparatus of the present invention, it is possible to improve the accuracy of the drive signal and further reduce the power consumption.
Further, in the liquid discharge apparatus of the present invention, the discharge destination potential preliminary adjustment waveform signal generating means adjusts the phase of the discharge destination potential preliminary adjustment signal to adjust the potential of the discharge destination potential preliminary adjustment signal. A potential pre-adjustment waveform signal is generated.

According to the liquid ejection apparatus of the present invention, it is possible to improve the accuracy of the drive signal and further reduce the power consumption.
The liquid ejection device of the present invention includes a plurality of nozzles provided in a liquid ejection head, a charge / discharge actuator provided corresponding to each nozzle, and a charge / discharge actuator of a nozzle that should eject ink droplets. In a liquid discharge apparatus including a driving unit that applies a driving signal, a driving waveform signal generating unit that generates a driving waveform signal serving as a reference of a signal that controls a driving state of the actuator, and a charge transistor that is push-pull connected And a driving signal generating means for amplifying the driving waveform signal generated by the driving waveform signal generating means by the discharging transistor and outputting a driving signal, and a pre-adjustment of the potential of the charging source to the driving signal generating means Charge source potential preliminary adjustment waveform signal generating means for generating a charge source potential preliminary adjustment waveform signal, a charge source to the drive signal generation means, and The charge source potential to the drive signal generating means is preliminarily adjusted based on the charge source potential preliminary adjustment waveform signal that is disposed between the dynamic signal generation means and generated by the charge source potential preliminary adjustment waveform signal generation means. Charge source potential preliminary adjustment means, discharge destination potential preliminary adjustment waveform signal generation means for generating a discharge destination potential preliminary adjustment waveform signal for preliminary adjustment of the discharge destination potential of the drive signal generation means, and the drive signal generation means The discharge from the drive signal generating means based on the discharge destination potential pre-adjusted waveform signal that is disposed between the discharge destination from the drive and the drive signal generating means and generated by the discharge destination potential pre-adjusted waveform signal generating means A discharge destination potential preliminary adjustment means for preliminarily adjusting the destination potential, wherein the charge source potential preliminary adjustment means is a charge source potential preliminary adjustment wave generated by the charge source potential preliminary adjustment waveform signal generation means. Charging source potential modulation means for pulse-modulating a signal and charging source potential for power amplification of a charging source potential modulation signal pulse-modulated by the charging source potential modulation means by a push-pull connected charging source potential transistor pair A power source potential smoothing filter that outputs a charge source potential preliminary adjustment signal amplified by the charge source potential digital power amplifier to a collector of a charge transistor of the drive signal generating means, The discharge destination potential preliminary adjustment means includes: a discharge destination potential modulation means for pulse-modulating the discharge destination potential preliminary adjustment waveform signal generated by the discharge destination potential preliminary adjustment waveform signal generation means; and a push destination connected discharge destination potential. A discharge destination potential deamplifier that amplifies the power of the discharge destination potential modulation signal pulse-modulated by the discharge destination potential modulation means by the transistor pair for discharge. A digital power amplifier, and a discharge destination potential smoothing filter that outputs the discharge destination potential preliminary adjustment signal amplified by the discharge destination potential digital power amplifier to the collector of the discharge transistor of the drive signal generating means. It is characterized by.

According to the liquid ejection apparatus of the present invention, the potential difference between the charge source potential preliminary adjustment signal and the drive signal for charging the charge / discharge actuator can be reduced, and the discharge destination potential preliminary adjustment signal and the charge / discharge actuator are discharged. The potential difference from the driving signal to be reduced can be reduced, and the power consumption can be reduced.
Further, in the liquid discharge apparatus of the present invention, the charging source potential preliminary adjustment waveform signal generating means is a charge for adjusting the potential of the charging source potential preliminary adjustment signal by adjusting the voltage value of the charging source potential preliminary adjustment signal. A discharge for generating an original potential preliminary adjustment waveform signal, and the discharge destination potential preliminary adjustment waveform signal generating means adjusts the voltage value of the discharge destination potential preliminary adjustment signal to adjust the potential of the discharge destination potential preliminary adjustment signal. A pre-potential pre-adjustment waveform signal is generated.

According to the liquid ejection apparatus of the present invention, it is possible to improve the accuracy of the drive signal and further reduce the power consumption.
Further, in the liquid ejection apparatus of the present invention, the charging source potential preliminary adjustment waveform signal generation unit adjusts the phase of the charging source potential preliminary adjustment signal to adjust the potential of the charging source potential preliminary adjustment signal. A discharge destination potential preliminary adjustment waveform signal is generated, and the discharge destination potential preliminary adjustment waveform signal generating means adjusts the phase of the discharge destination potential preliminary adjustment signal to adjust the potential of the discharge destination potential preliminary adjustment signal. A pre-adjusted waveform signal is generated.

According to the liquid ejection apparatus of the present invention, it is possible to improve the accuracy of the drive signal and further reduce the power consumption.
The liquid ejection device of the present invention includes a plurality of nozzles provided in a liquid ejection head, a charge / discharge actuator provided corresponding to each nozzle, and a charge / discharge actuator of a nozzle that should eject ink droplets. In a liquid discharge apparatus including a driving unit that applies a driving signal, a driving waveform signal generating unit that generates a driving waveform signal serving as a reference of a signal that controls a driving state of the actuator, and a charge transistor that is push-pull connected And a driving signal generating means for amplifying the driving waveform signal generated by the driving waveform signal generating means by the discharging transistor and outputting a driving signal, a potential of the charge source to the driving signal generating means, and the driving signal generating means Charge source and destination potential reserve for generating a charge source and discharge destination potential preliminary adjustment waveform signal for preconditioning the potential of the discharge destination from Preliminary waveform for adjusting the potential of the charging source and the destination of the charging, and arranged between the driving signal generating means, the charging source to the driving signal generating means, the power source from the driving signal generating means, and the driving signal generating means. A charge source and a discharge destination that preliminarily adjust a charge source potential to the drive signal generation unit and a discharge destination potential from the drive signal generation unit based on a charge source and discharge destination potential preliminary adjustment waveform signal generated by the signal generation unit Potential pre-adjustment means, and the charge source and discharge destination potential pre-adjustment means pulse modulate the charge source and discharge destination potential pre-adjustment waveform signal generated by the charge source and discharge destination potential pre-adjustment waveform signal generation means The charge source and discharge destination potential modulation means, and the charge source and discharge destination potential modulation means are pulse-modulated by a push-pull connected charge source and discharge destination potential transistor pair. Charging source and discharging destination potential digital power amplifier for power amplification of charging source and discharging destination potential modulation signal, and charging source and discharging destination potential preliminary adjustment signal amplified by the charging source and discharging destination potential digital power amplifier And a smoothing filter for a charging source and a discharging destination potential for outputting to the collector of the charging transistor and the collector of the discharging transistor of the drive signal generating means.

According to the liquid ejection apparatus of the present invention, the potential difference between the charge source / discharge destination potential preliminary adjustment signal and the drive signal for charging / discharging the charge / discharge actuator can be reduced, and the power consumption can be reduced. .
Further, in the liquid discharge apparatus of the present invention, the charging source and discharge destination potential preliminary adjustment waveform signal generating means adjusts the voltage value of the charging source and discharge destination potential preliminary adjustment signal, thereby adjusting the charging source and discharge destination potentials. A charge source and discharge destination potential preliminary adjustment waveform signal for adjusting the potential of the preliminary adjustment signal is generated.

According to the liquid ejection apparatus of the present invention, it is possible to improve the accuracy of the drive signal and further reduce the power consumption.
Further, in the liquid discharge apparatus of the present invention, the charging source and discharge destination potential preliminary adjustment waveform signal generating means adjusts the phase of the charging source and discharge destination potential preliminary adjustment signal to thereby adjust the charging source and discharge destination potential preliminary. A charge source and discharge destination potential preliminary adjustment waveform signal for adjusting the potential of the adjustment signal is generated.

  According to the liquid ejection apparatus of the present invention, it is possible to improve the accuracy of the drive signal and further reduce the power consumption.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram illustrating a first embodiment of an ink jet printer to which a liquid ejection apparatus of the present invention is applied, where (a) is a plan view and (b) is a front view. It is a block block diagram of the control apparatus of the inkjet printer of FIG. It is explanatory drawing of drive waveform signal generation. It is explanatory drawing of the drive waveform signal or drive signal connected in time series. It is a block block diagram of a drive signal generation system. It is a block diagram of the selection part which connects a drive signal to an actuator. FIG. 6 is a block diagram showing details of a drive signal generation circuit and a potential preliminary adjustment circuit of the drive signal generation system of FIG. 5. It is explanatory drawing of an effect | action of the digital power amplifier of the electric potential preliminary adjustment circuit of FIG. It is explanatory drawing of an effect | action of the drive signal generation system of FIG. It is a block diagram of a conventional drive signal generation system and an explanatory diagram of its operation. It is a block block diagram of the drive signal generation system which shows 2nd Embodiment of the inkjet printer to which the liquid discharge apparatus of this invention is applied. It is explanatory drawing of an effect | action of the drive signal generation system of FIG. It is a block block diagram of the drive signal generation system which shows 3rd Embodiment of the inkjet printer to which the liquid discharge apparatus of this invention is applied. It is explanatory drawing of an effect | action of the drive signal generation system of FIG. It is a block block diagram of the drive signal generation system which shows 4th Embodiment of the inkjet printer to which the liquid discharge apparatus of this invention is applied. It is explanatory drawing of an effect | action of the drive signal generation system of FIG.

Next, a first embodiment of an ink jet printer to which the liquid ejection apparatus of the present invention is applied will be described with reference to the drawings.
FIG. 1 is a schematic configuration diagram of the ink jet printer of the present embodiment, FIG. 1a is a plan view thereof, and FIG. 1b is a front view thereof. In FIG. 1, a print medium 1 is a line head type ink jet printer that is transported in the direction of the arrow in the figure from the right to the left in the figure, and is printed in a print area in the middle of the conveyance. However, the ink jet head of the present embodiment is arranged not only at one place but also at two places.

  Reference numeral 2 in the figure denotes a first inkjet head provided on the upstream side in the conveyance direction of the print medium 1, and reference numeral 3 denotes a second inkjet head provided on the downstream side, and below the first inkjet head 2. Is provided with a first transport unit 4 for transporting the print medium 1, and a second transport unit 5 is provided below the second inkjet head 3. The first transport unit 4 includes four first transport belts 6 arranged at predetermined intervals in a direction intersecting with the transport direction of the print medium 1 (hereinafter also referred to as nozzle row direction). Similarly, the second transport unit 5 includes four second transport belts 7 arranged at predetermined intervals in a direction (nozzle row direction) intersecting the transport direction of the print medium 1.

The four second conveyor belts 7 as well as the four first conveyor belts 6 are arranged alternately adjacent to each other. In the present embodiment, among these conveyor belts 6, 7, two first conveyor belts 6 and 2 on the right side in the nozzle row direction and two first conveyor belts 6 and second on the left side in the nozzle row direction. The conveyor belt 7 is separated. That is, the right driving roller 8R is disposed in the overlapping portion of the two first conveyance belts 6 and the second conveyance belt 7 on the right side in the nozzle row direction, and the two first conveyance belts 6 and the second conveyance belts on the left side in the nozzle row direction. 7 is provided with a left driving roller 8L, a right first driven roller 9R and a left first driven roller 9L on the upstream side, and a right second driven roller 10R and a second left side on the downstream side. A driven roller 10L is provided. These rollers appear as a series, but are substantially divided at the central portion of FIG. 1a. The two first conveying belts 6 on the right side in the nozzle row direction are wound around the right driving roller 8R and the first driven roller 9R on the right side, and the two first conveying belts 6 on the left side in the nozzle row direction are connected to the left driving roller 8L and the left side. The two second conveying belts 7 on the right side in the nozzle row direction are wound around the first driven roller 9L, and the two second conveying belts on the left side in the nozzle row direction are wound on the right driving roller 8R and the second right driven roller 10R. 7 is wound around the left driving roller 8L and the second left driven roller 10L. The right electric motor 11R is connected to the right driving roller 8R, and the left electric motor 11L is connected to the left driving roller 8L. Accordingly, when the right driving roller 8R is rotationally driven by the right electric motor 11R, the first conveying unit 4 composed of the two first conveying belts 6 on the right side in the nozzle row direction and the two second conveying belts on the right side in the nozzle row direction. The second conveyance unit 5 configured by 7 moves in synchronization with each other at the same speed, and is configured by two first conveyance belts 6 on the left side in the nozzle row direction when the left driving roller 8L is rotationally driven by the left electric motor 11L. The second transport unit 5 including the first transport unit 4 and the two second transport belts 7 on the left side in the nozzle row direction are synchronized with each other and move at the same speed. However, if the rotation speeds of the right electric motor 11R and the left electric motor 11L are different, the conveyance speed in the left and right directions in the nozzle row can be changed. Specifically, the rotation speed of the right electric motor 11R is set to When the rotational speed is higher than the rotation speed, the conveyance speed on the right side in the nozzle row direction can be made larger than that on the left side, and when the rotation speed of the left electric motor 11L is higher than the rotation speed of the right electric motor 11R. The speed can be greater than the right side.

  The first inkjet head 2 and the second inkjet head 3 are shifted in the transport direction of the printing medium 1 for each of four colors, for example, yellow (Y), magenta (M), cyan (C), and black (K). It is arranged. Ink is supplied to each inkjet head 2 and 3 from an ink tank of each color (not shown) via an ink supply tube. Each inkjet head 2, 3 is formed with a plurality of nozzles in the direction intersecting with the conveyance direction of the print medium 1 (that is, in the nozzle row direction), and a necessary amount of ink droplets are simultaneously applied from the nozzles to necessary locations. By discharging, minute ink dots are formed and output on the printing medium 1. By performing this for each color, it is possible to perform so-called one-pass printing by passing the print medium 1 conveyed by the first conveyance unit 4 and the second conveyance unit 5 once. That is, the area where the inkjet heads 2 and 3 are disposed corresponds to the printing area.

  As a method for discharging and outputting ink from each nozzle of the ink jet head, there are an electrostatic method, a piezo method, a film boiling ink jet method, and the like. In the electrostatic system, when a drive signal is given to the electrostatic gap, which is an actuator, the diaphragm in the cavity is displaced, causing a pressure change in the cavity, and ink drops are ejected from the nozzle by the pressure change. It is. In the piezo method, when a drive signal is given to a piezo element that is an actuator, the diaphragm in the cavity is displaced to cause a pressure change in the cavity, and ink droplets are ejected from the nozzle by the pressure change. . In the film boiling ink jet method, there is a minute heater in the cavity, the ink is instantaneously heated to 300 ° C. or more, the ink becomes a film boiling state, bubbles are generated, and ink droplets are ejected from the nozzle by the pressure change. That's it. The present invention can be applied to any ink output method, but is particularly suitable for a piezo element that can adjust the ejection amount of ink droplets by adjusting the peak value of the drive signal and the voltage increase / decrease slope. The piezo element is a so-called charge / discharge actuator having a capacity.

The ink droplet ejection nozzles of the first inkjet head 2 are formed only between the four first conveyance belts 6 of the first conveyance unit 4, and the ink droplet ejection nozzles of the second inkjet head 3 are the second conveyance. It is formed only between the four second conveyor belts 7 of the section 5. This is because the inkjet heads 2 and 3 are cleaned by a cleaning unit, which will be described later, but in this way, one-pass printing cannot be performed with only one of the inkjet heads. For this reason, the first ink jet head 2 and the second ink jet head 3 are arranged so as to be shifted in the transport direction of the print medium 1 in order to compensate for the portions that cannot be printed with each other.

  Disposed below the first inkjet head 2 is the first cleaning cap 12 for cleaning the first inkjet head 2, and disposed below the second inkjet head 3 is the second inkjet head. 2 is a second cleaning cap 13 that cleans 3. Each of the cleaning caps 12 and 13 has such a size that it can pass between the four first conveying belts 6 of the first conveying unit 4 and between the four second conveying belts 7 of the second conveying unit 5. It is formed. These cleaning caps 12 and 13 are, for example, a rectangular bottomed cap body that covers the nozzles formed on the lower surfaces of the ink jet heads 2 and 3, that is, the nozzle surfaces and can be in close contact with the nozzle surfaces, and is disposed at the bottom thereof. And a tube pump connected to the bottom of the cap body, and a lifting device that lifts and lowers the cap body. Therefore, the cap body is raised by the lifting device and is brought into close contact with the nozzle surfaces of the inkjet heads 2 and 3. In this state, when the cap body is made negative pressure by the tube pump, ink droplets and bubbles are sucked out from the nozzles established on the nozzle surfaces of the ink jet heads 2 and 3, and the ink jet heads 2 and 3 can be cleaned. . When the cleaning is completed, the cleaning caps 12 and 13 are lowered.

  On the upstream side of the first driven rollers 9R and 9L, there are two pairs of gate rollers 14 that adjust the paper feed timing of the printing medium 1 supplied from the paper feeding unit 15 and correct the skew of the printing medium 1. Is provided. The skew is a twist of the print medium 1 with respect to the transport direction. A pickup roller 16 for supplying the print medium 1 is provided above the paper supply unit 15. Reference numeral 17 in the drawing denotes a gate roller motor that drives the gate roller 14.

  A belt charging device 19 is disposed below the drive rollers 8R and 8L. The belt charging device 19 includes a charging roller 20 that is in contact with the first conveying belt 6 and the second conveying belt 7 with the driving rollers 8R and 8L interposed therebetween, and the charging roller 20 is connected to the first conveying belt 6 and the second conveying belt 7. It comprises a spring 21 to be pressed and a power source 18 for applying a charge to the charging roller 20, and charges the first conveying belt 6 and the second conveying belt 7 from the charging roller 20 to charge them. In general, these belts are formed of a medium / high resistance body or an insulator, and when charged by the belt charging device 19, the charge applied to the surface thereof is also composed of a high resistance body or an insulator. The print medium 1 can be caused to generate dielectric polarization, and the print medium 1 can be adsorbed to the belt by electrostatic force generated between the charge generated by the dielectric polarization and the charge on the belt surface. The belt charging device 19 may be a so-called corotron that drops the charge.

  Therefore, according to this ink jet printer, the belt charging device 19 charges the surfaces of the first conveyance belt 6 and the second conveyance belt 7, and in this state, the print medium 1 is fed from the gate roller 14, and a spur (not shown) When the printing medium 1 is pressed against the first conveying belt 6 by a paper pressing roller composed of a roller, the printing medium 1 is attracted to the surface of the first conveying belt 6 by the action of the dielectric polarization described above. In this state, when the driving rollers 8R and 8L are rotationally driven by the electric motors 11R and 11L, the rotational driving force is transmitted to the first driven rollers 9R and 9L via the first conveying belt 6.

In this way, the first conveyance belt 6 is moved downstream in the conveyance direction while the print medium 1 is adsorbed, and the print medium 1 is moved below the first inkjet head 2 to be formed on the first inkjet head 2. Printing is performed by ejecting ink droplets from the nozzles. When the printing by the first ink jet head 2 is completed, the print medium 1 is moved downstream in the transport direction and transferred onto the second transport belt 7 of the second transport unit 5. As described above, since the surface of the second transport belt 7 is also charged by the belt charging device 19, the print medium 1 is attracted to the surface of the second transport belt 7 by the action of the dielectric polarization described above.

  In this state, the second conveying belt 7 is moved downstream in the conveying direction, the printing medium 1 is moved below the second inkjet head 3, and ink droplets are ejected from nozzles formed on the second inkjet head. Print. When printing by the second ink jet head is completed, the print medium 1 is further moved downstream in the transport direction, and discharged to the paper discharge unit while separating the print medium 1 from the surface of the second transport belt 7 by a separation device (not shown). To do.

  When the first and second inkjet heads 2 and 3 need to be cleaned, the first and second cleaning caps 12 and 13 are raised as described above to raise the nozzle surfaces of the first and second inkjet heads 2 and 3. In this state, the cap body is brought into a negative pressure so that ink drops and bubbles are sucked out from the nozzles of the first and second ink jet heads 2 and 3 and cleaned. 2 Lower the cleaning caps 12 and 13.

  A control device for controlling itself is provided in the ink jet printer. For example, as shown in FIG. 2, the control device prints on a print medium by controlling a printing device, a paper feeding device, and the like based on print data input from a host computer 60 such as a personal computer or a digital camera. The processing is performed. An input interface unit 61 that receives print data input from the host computer 60, a control unit 62 configured by, for example, a microcomputer that executes print processing based on the print data input from the input interface unit 61, A gate roller motor driver 63 for driving and controlling the gate roller motor 17, a pickup roller motor driver 64 for driving and controlling the pickup roller motor 51 for driving the pickup roller 16, and a head driver 65 for driving and controlling the inkjet heads 2 and 3. The right electric motor driver 66R for driving and controlling the right electric motor 11R, the left electric motor driver 66L for driving and controlling the left electric motor 11L, and the output signals of the drivers 63 to 65, 66R and 66L are externally gated. Ramota 17, the pickup roller motor 51, the inkjet heads 2 and 3, the right electric motor 11R, configured to include an interface 67 for converting the drive signal used in the left side electric motor 11L.

The control unit 62 is a CPU (Central Processing Unit) that executes various processes such as a printing process.
62a and a RAM (temporarily storing print data input via the input interface 61 or various data when executing the print data print processing, or temporarily expanding an application program such as print processing A random access memory (Random Access Memory) 62c and a ROM (Read-Only Memory) 62d composed of a non-volatile semiconductor memory storing a control program executed by the CPU 62a are provided. When the control unit 62 obtains print data (image data) from the host computer 60 via the interface unit 61, the CPU 62a performs a predetermined process on the print data and ejects ink droplets from any nozzle. Or print data (driving signal selection data SI & SP) indicating how much ink droplets are to be ejected, and the drivers 63 to 65, 66R, 66L are controlled based on the print data and input data from various sensors. Output a signal. When control signals are output from the drivers 63 to 65, 66R, and 66L, these are converted into drive signals by the interface unit 67, and actuators corresponding to a plurality of nozzles of the inkjet head, the gate roller motor 17, and the pickup roller motor 51. The right electric motor 11R and the left electric motor 11L are operated, respectively, to feed and convey the print medium 1, control the posture of the print medium 1, and print processing on the print medium 1. Each component in the control unit 62 is electrically connected through a bus (not shown).

  The head driver 65 includes a drive waveform signal generation circuit 70 that forms a drive waveform signal WCOM, and a potential preliminary adjustment waveform signal generation circuit 71 that forms a charge source potential preliminary adjustment waveform signal WCCOM and a discharge destination potential preliminary adjustment waveform signal WDCOM. I have. For example, as shown in FIG. 3, the drive waveform signal generation circuit 70 generates waveform data at the rise timing of the clock signal from the state where the drive waveform signal WCOM is raised to the intermediate potential (offset) during the time width T1. The drive waveform signal WCOM is added by + ΔV1, and then the drive waveform signal WCOM is held at a constant value during the time width T0 (waveform data 0). Then, during the time width T2, the waveform data at the rising timing of the clock signal − The drive waveform signal WCOM is subtracted by ΔV2. The drive waveform signal WCOM generated in this way is converted into an analog signal by, for example, the drive signal generation circuit 72 shown in FIG. 5, and the power is amplified and supplied to the inkjet heads 2 and 3 as the drive signal COM. An actuator such as a piezo element provided can be driven, and ink droplets can be ejected from each nozzle.

  The rising portion of the drive signal COM is a stage in which the volume of the cavity (pressure chamber) communicating with the nozzle is enlarged and ink is drawn in (it can be said that the meniscus is drawn in view of the ink discharge surface), and the fall of the drive signal COM The portion is a stage where the cavity volume is reduced and the ink is pushed out (which can be said to push out the meniscus in view of the ink discharge surface). As a result of the ink being pushed out, ink droplets are ejected from the nozzles. Incidentally, the waveform of the drive signal COM or the drive waveform signal WCOM can be adjusted by the waveform data 0, + ΔV1, −ΔV2, + ΔV3, and the clock signal for generating the drive waveform signal WCOM, as can be easily estimated from the foregoing. . In addition, since the piezo element is a capacitive load and is a so-called charge / discharge actuator, for example, in this embodiment, the charge / discharge actuator is charged at the rising portion of the drive signal COM and charged at the falling portion of the drive signal COM. Electric charges are discharged from the discharge actuator.

  By variously changing the voltage increase / decrease slope and peak value of the drive signal COM consisting of this voltage trapezoidal wave, the ink drawing amount and drawing speed, the ink pushing amount and the pushing speed can be changed. It is possible to obtain different ink dot sizes by changing the amount of ink discharged. Therefore, for example, as shown in FIG. 4, a plurality of drive pulses PCOM are connected in time series to generate a drive signal COM, from which a single drive pulse PCOM is selected and supplied to an actuator 22 such as a piezo element. Various ink dot sizes can be obtained by ejecting ink droplets, selecting a plurality of drive pulses PCOM, supplying them to the actuator 22 such as a piezo element, and ejecting ink droplets a plurality of times. . That is, if a plurality of ink droplets land on the same position before the ink is dried, it is substantially the same as ejecting a large ink droplet, and the size of the ink dot can be increased. It is possible to increase the number of gradations by combining such techniques. Note that the drive pulse PCOM1 at the left end in FIG. 4 is not pushed out but only drawn in ink. This is called microvibration and is used, for example, to suppress or prevent nozzle drying without discharging ink droplets.

  As a result, the inkjet heads 2 and 3 select the nozzle to be ejected based on the drive signal COM generated by the drive signal generation circuit 72 and the print data, and the connection timing to the drive signal COM of an actuator such as a piezo element. Drive signal selection data signal SI & SP for determining the drive signal, latch signal LAT and channel for connecting the drive signal COM and the actuators of the inkjet heads 2 and 3 based on the drive signal selection data SI & SP after nozzle selection data is input to all nozzles A clock signal SCK for transmitting the signal CH and the drive signal selection data signal SI & SP as serial signals to the inkjet heads 2 and 3 is input.

  Next, a configuration for connecting the drive signal COM output from the drive signal generation circuit and an actuator such as a piezoelectric element will be described. FIG. 6 is a block diagram of a selection unit that connects the drive signal COM and an actuator such as a piezo element. The selection unit includes a shift register 211 that stores drive signal selection data SI & SP for designating an actuator such as a piezo element corresponding to a nozzle that should eject ink droplets, and a latch that temporarily stores data in the shift register 211. The circuit 212, a level shifter 213 that converts the output of the latch circuit 212, and a selection switch 201 that connects the drive signal COM to the actuator 22 such as a piezo element in accordance with the output of the level shifter.

  The drive signal selection data signal SI & SP is sequentially input to the shift register 211, and the storage area is sequentially shifted from the first stage to the subsequent stage in accordance with the input pulse of the clock signal SCK. The latch circuit 212 latches each output signal of the shift register 211 by the input latch signal LAT after the drive signal selection data SI & SP for the number of nozzles is stored in the shift register 211. The signal stored in the latch circuit 212 is converted by the level shifter 213 to a voltage level at which the selection switch 201 at the next stage can be turned on / off. This is because the drive signal COM is higher than the output voltage of the latch circuit 212, and the operating voltage range of the selection switch 201 is set higher accordingly. Accordingly, an actuator such as a piezo element whose selection switch 201 is closed by the level shifter 213 is connected to the drive signal COM at the connection timing of the drive signal selection data SI & SP. In addition, after the drive signal selection data SI & SP of the shift register 211 is stored in the latch circuit 212, the next print information is input to the shift register 211, and the stored data in the latch circuit 212 is sequentially updated in accordance with the ink droplet ejection timing. To do. In addition, the code | symbol HGND in a figure is a ground end of actuators, such as a piezo element. Further, according to the selection switch 201, the input voltage of the actuator 22 is maintained at the voltage just before the disconnection even after the actuator such as the piezo element is disconnected from the drive signal COM.

  Returning to FIG. 5, in order to amplify the power of the drive signal COM as described above, a charge transistor and a discharge transistor that are push-pull connected as described later are disposed between the power source and the ground, and The push-pull connected transistor pair is linearly driven in accordance with the drive waveform signal WCOM. For example, a potential difference between a drive signal for charging a charge / discharge actuator such as a piezo element and a power supply potential (charge source potential), or a drive signal for discharging from a charge / discharge actuator and a ground potential (discharge destination potential). A product obtained by multiplying the potential difference by the current value is power consumption. As described above, the power consumption is almost consumed as heat. However, if the potential difference is large, the power consumption increases and the heat generation amount also increases. Therefore, in this embodiment, drive signal generation is performed in the potential preliminary adjustment circuits 26 and 27 based on the charge source potential preliminary adjustment waveform signal WCCOM and the discharge destination potential preliminary adjustment waveform signal WDCOM generated by the potential preliminary adjustment waveform signal generation circuit 71. By adjusting the charge source potential to the circuit 72 and the discharge destination potential from the drive signal generation circuit 72, the potential difference between the drive signal and the charge source potential for charging the charge / discharge actuator or the discharge from the charge / discharge actuator Therefore, the potential difference between the drive signal and the discharge destination potential is reduced, thereby reducing power consumption and heat generation. The drive signal generation circuit 72 and the potential preliminary adjustment circuits 26 and 27 are built in the interface unit 67.

FIG. 7 shows specific circuit configurations of the potential preliminary adjustment circuit 26 and the drive signal generation circuit 72 of the present embodiment. In the present embodiment, only the charge source potential preliminary adjustment circuit 26 that preliminarily adjusts the charge source potential to the drive signal generation circuit 72 is provided. Among these, the drive signal generation circuit 72 is equivalent to that described in Patent Document 2 described above, and the push-pull connected charge transistor Tr1 and discharge transistor Tr2, and the drive waveform signal WCOM made up of digital signals. A D / A converter 701 that performs analog conversion and a base driver circuit 702 that controls the base voltages of the two transistors Tr1 and Tr2 in accordance with the analog-converted drive waveform signal WCOM are configured. N of one of the two transistors Tr1 and Tr2
A charging source potential preliminary adjustment signal CCOM is supplied from the charging source potential preliminary adjustment circuit 26 to the collector of the PN-type charging transistor Tr 1, the collector is connected to the input side of the selection switch 201, and the base is one of the base driver circuits 702. Connected to the output. The collector of the other PNP type discharge transistor Tr 2 is connected to the input side of the selection switch 201, the collector is grounded, and the base is connected to the other output of the base driver circuit 702. In this transistor pair, one charging transistor Tr1 supplies electric charge to the actuator 22 which is a capacitive load from the charging source potential preliminary adjustment signal CCOM through the selection switch 201 while accompanying a voltage waveform corresponding to the drive pulse COM. That is, charging is performed, and the other discharging transistor Tr2 discharges the electric charge of the actuator 22 which is a capacitive load through the selection switch 201 with a voltage waveform corresponding to the driving pulse COM.

  On the other hand, the charging source potential preliminary adjustment circuit 26 includes, for example, a charging source potential modulation circuit 24 that performs pulse modulation on the charging source potential preliminary adjustment waveform signal WCCOM generated in the same manner as the drive waveform signal WCOM described above, and the charging source potential. A charging source potential digital power amplifier that power-amplifies the charging source potential modulation signal CPWM pulse-modulated by the modulation circuit 24, so-called class D amplifier 28, and charging amplified by the charging source potential digital power amplifier 28 A charge source potential smoothing filter 30 that smoothes the source potential preliminary adjustment signal CCOM and outputs the smoothed output to the collector of the charge transistor Tr1 of the drive signal generation circuit 72 is provided.

  A general pulse width modulation (PWM) circuit is used as the charging source potential modulation circuit 24 that performs pulse modulation on the charging source potential preliminary adjustment waveform signal WCCOM. The charging source potential modulation circuit 24 of FIG. 7 includes a known triangular wave signal oscillator and a comparator that compares the triangular wave signal output from the triangular wave signal oscillator with the charging source potential preliminary adjustment waveform signal WCCOM. Composed. According to the charging source potential modulation circuit 24, for example, Hi when the charging source potential preliminary adjustment waveform signal WCCOM is greater than or equal to the triangular wave signal, and Lo when the charging source potential preliminary adjustment waveform signal WCCOM is less than the triangular wave signal. A modulation signal, a so-called PWM signal is output. In this embodiment, the pulse width modulation circuit is used as the pulse modulation circuit, but a pulse density modulation (PDM) circuit may be used instead.

  The charging source potential digital power amplifier, so-called class D amplifier 28, is composed of two MOSFETs TrP and TrN for substantially amplifying power, and is generally referred to as a charging source potential transistor pair 32; A gate driver circuit 34 for adjusting the gate-source signals GP and GN of the MOSFETs TrP and TrN based on the charging source potential modulation signal CPWM from the charging source potential modulation circuit 24; The source potential transistor pair 32 is a combination of a high-side MOSFET TrP and a low-side MOSFET TrN in a push-pull type. Among these, when the gate-source signal of the high-side MOSFET TrP is GP, the gate-source signal of the low-side MOSFET TrN is GN, and the output of the charging source potential transistor pair 32 is Va, these are the modulations for the charging source potential. FIG. 8 shows how it changes in accordance with the signal CPWM. This output characteristic is the same for the discharge destination potential transistor pair 33 that amplifies the power of a discharge destination potential modulation signal DPWM described later.

For example, in this embodiment, when the charging source potential modulation signal CPWM is at the Hi level, the gate-source signal GP of the high-side MOSFET TrP is at the Hi level, and the gate-source signal GN of the low-side MOSFET TrN is at the Lo level. Therefore, the high-side MOSFET TrP is turned on and the low-side MOSFET TrN is turned off. As a result, the output Va of the charge source potential transistor pair 32 becomes, for example, the charge source potential Vdd. On the other hand, when the charging source potential modulation signal CPWM is at the Lo level, the gate-source signal GP of the high-side MOSFET TrP is at the Lo level, and the gate-source signal GN of the low-side MOSFET TrN is at the Hi level. The side-side MOSFET TrP is turned off and the low-side MOSFET TrN is turned on. As a result, the output Va of the charge source potential transistor pair 32 becomes zero.

  The output Va of the charge source potential transistor pair 32 of the charge source potential digital power amplification circuit 28 is supplied to the collector of the charge transistor Tr1 of the drive signal generation circuit 72 via the charge source potential smoothing filter 30 and precharged. Supplied as signal CCOM. The charging source potential smoothing filter 30 is formed of, for example, an LC low-pass (low-pass) filter including a combination of one coil L and one capacitor C. The charge source potential smoothing filter 30 comprising a low-pass filter sufficiently attenuates the high-frequency component of the output Va of the charge source potential transistor pair 32 of the charge source potential digital power amplifier circuit 28, that is, the pulse modulation carrier signal component. Further, the charging source potential preliminary adjustment signal CCOM is designed not to attenuate.

  In this embodiment, the potential of the charging source potential preliminary adjustment signal CCOM supplied to the collector of the charging transistor Tr1 of the driving signal generation circuit 72 is driven by appropriately setting the charging source potential preliminary adjustment waveform signal WCCOM. Adjustment is made so as to be slightly higher than the potential of the signal COM. There are two kinds of methods for adjusting the potential of the charge source potential preliminary adjustment signal CCOM. For example, the one shown in FIG. 9a is a voltage value of the charge source potential preliminary adjustment signal CCOM that is slightly higher than the potential of the drive signal COM. In FIG. 9b, the phase of the charging source potential preliminary adjustment signal CCOM is made earlier than that of the driving signal COM so that the potential of the charging source potential preliminary adjustment signal CCOM is changed to the potential of the driving signal. It is adjusted to be slightly higher.

  In this embodiment, the shaded area in FIGS. 9a and 9b corresponds to power consumption. In this embodiment, since the discharge destination potential is not preliminarily adjusted, the power consumption due to the potential difference between the drive signal COM and the discharge destination potential, that is, the ground potential does not change, but the collector of the charging transistor Tr1 of the drive signal generation circuit 72 Is adjusted so that the potential of the charge source potential preliminary adjustment signal CCOM supplied to is slightly higher than the potential of the drive signal COM, so that the power consumption due to the potential difference between them is small. FIG. 10a shows a conventional inkjet printer described in Patent Document 2 in which the charging source potential preliminary adjustment circuit 26 is not provided and the charging source potential Vdd is supplied to the collector of the charging transistor Tr1 of the drive signal generation circuit 72 as it is. In FIG. 10b, the power consumption is indicated by the hatched portion as in FIG. For ease of understanding, the same reference numerals as those in the embodiment are used. In this power consumption diagram, the potential difference between the charging source potential Vdd and the drive signal COM is larger than that of the present embodiment in which the charging source potential is preliminarily adjusted, and the power consumption is naturally large. When the power consumption increases, the amount of heat generation increases, so the size of the transistor used must be increased to improve heat resistance, or a heat sink must be provided to actively dissipate heat. On the other hand, in this embodiment, power consumption can be reduced and the amount of heat generated can be reduced as compared with the conventional ink jet printer, so that such measures are not necessary. The charge source potential preliminary adjustment signal CCOM supplied to the collector of the charge transistor Tr1 of the drive signal generating circuit 72 is amplified by the charge source potential digital power amplifier 28 including the charge source potential transistor pair 32 for preliminary adjustment. By doing so, the potential of the charge source potential preliminary adjustment signal CCOM can be accurately adjusted.

Thus, according to the ink jet printer of the present embodiment, the drive waveform signal generation circuit 70 generates the drive waveform signal WCOM that serves as a reference for the signal for controlling the drive state of the actuator 22, and the generated drive waveform signal WCOM. Is amplified by the push-pull-connected charging transistor Tr1 and the discharging transistor Tr2 of the drive signal generation circuit 72 and the drive signal COM is output to preliminarily adjust the charge source potential to the drive signal generation circuit 72. A charging source potential preliminary adjustment waveform signal WCCOM is generated, the charging source potential preliminary adjustment waveform signal WCCOM is pulse-modulated by the charging source potential modulation circuit 24, and the pulse-modulated charging source potential modulation signal CPWM is used as the charging source potential. Source pair transistor 3 for push-pull connection of digital power amplifier 28 for power supply The charge source potential preliminary adjustment signal CCOM amplified by the power source is smoothed by the charge source potential smoothing filter 30 and output to the collector of the charge transistor Tr1 of the drive signal generation circuit 72. The potential difference between the potential preliminary adjustment signal CCOM and the drive signal COM for charging the charge / discharge actuator can be reduced, and the power consumption can be reduced.

Further, if the charging source potential preliminary adjustment waveform signal WCCOM for adjusting the potential of the charging source potential preliminary adjustment signal CCOM is generated by adjusting the voltage value of the charging source potential preliminary adjustment signal CCOM, the drive signal COM The accuracy can be improved and the power consumption can be further reduced.
If the charge source potential preliminary adjustment waveform signal WCCOM that adjusts the potential of the charge source potential preliminary adjustment signal CCOM by adjusting the phase of the charge source potential preliminary adjustment signal CCOM is generated, the accuracy of the drive signal COM It is possible to improve and further reduce power consumption.

  Next, a second embodiment of the inkjet printer of the present invention will be described with reference to FIG. The schematic configuration, control device, drive waveform signal and drive signal generation method, and actuator selection configuration of the ink jet printer of this embodiment are the same as those of the first embodiment. In this embodiment, a discharge destination potential preliminary adjustment circuit 27 is provided instead of the charge source potential preliminary adjustment circuit 26 of the first embodiment. This discharge destination potential preliminary adjustment circuit 27 is connected to the collector of the discharge transistor Tr2 of the drive signal generation circuit 72, and preliminarily adjusts the destination potential discharged from the discharge transistor Tr2. The collector of the charging transistor Tr1 of the drive signal generating circuit 72 is connected to the charging source potential Vdd.

  The discharge destination potential preliminary adjustment circuit 27 includes, for example, a discharge destination potential modulation circuit 25 that performs pulse modulation on the discharge destination potential preliminary adjustment waveform signal WDCOM generated in the same manner as the drive waveform signal WCOM described above. A discharge destination potential digital power amplifier, so-called class D amplifier 29, which amplifies the power of the discharge destination potential modulation signal DPWM pulse-modulated by the modulation circuit 25, and a discharge destination whose power is amplified by the discharge destination potential digital power amplifier 29. A discharge destination potential smoothing filter 31 that smoothes the potential preliminary adjustment signal DCOM and outputs it to the collector of the discharge transistor Tr2 of the drive signal generation circuit 72 is provided.

  The discharge destination potential modulation circuit 25 that performs pulse modulation of the discharge destination potential preliminary adjustment waveform signal WDCOM is similar to the charge source potential modulation circuit 24 of the first embodiment in that it is a general pulse width modulation (PWM) circuit. Was used. In addition, the discharge destination potential digital power amplifier, so-called class D amplifier 29, is similar to the charge source potential digital power amplifier 28 of the first embodiment from two MOSFETs TrP and TrN for substantially amplifying power. And a gate for adjusting the gate-source signals GP and GN of the MOSFETs TrP and TrN on the basis of the discharge destination potential modulation signal DPWM from the discharge destination potential modulation circuit 25. The driver circuit 34 is provided. Similarly to the charge source potential smoothing filter 30 of the first embodiment, the discharge destination potential smoothing filter 31 is also an LC low-pass (low-pass) filter comprising a combination of one coil L and one capacitor C, for example. Consists of.

  In this embodiment, the potential of the discharge destination potential preliminary adjustment signal DCOM supplied to the collector of the discharge transistor Tr2 of the drive signal generation circuit 72 is driven by appropriately setting the discharge destination potential preliminary adjustment waveform signal WDCOM. Adjustment is made so that it is slightly lower than the potential of the signal COM. There are two kinds of methods for adjusting the potential of the discharge destination potential preliminary adjustment signal DCOM. For example, the one shown in FIG. 12A has a voltage value of the discharge destination potential preliminary adjustment signal DCOM that is slightly lower than the potential of the drive signal COM. In FIG. 12b, the potential of the discharge destination potential preliminary adjustment signal DCOM is set to the potential of the drive signal by making the phase of the discharge destination potential preliminary adjustment signal DCOM earlier than that of the drive signal COM. It is adjusted to be slightly lower.

  In the present embodiment, the shaded area in FIGS. 12a and 12b corresponds to power consumption. In this embodiment, since the charge source potential is not preliminarily adjusted, the power consumption due to the potential difference between the drive signal COM and the discharge source potential Vdd does not change, but is supplied to the collector of the discharge transistor Tr2 of the drive signal generation circuit 72. Since the potential of the discharge destination potential preliminary adjustment signal DCOM is adjusted to be slightly lower than the potential of the drive signal COM, power consumption due to the potential difference between the two is small. Therefore, in this embodiment, since power consumption can be reduced and the amount of heat generated can be reduced as compared with the conventional ink jet printer, no countermeasure is required. In addition, the discharge destination potential preliminary adjustment signal DCOM supplied to the collector of the discharge transistor Tr2 of the drive signal generation circuit 72 is amplified by the discharge destination potential digital power amplifier 29 including the discharge destination potential transistor pair 33 for preliminary adjustment. By doing so, the potential of the discharge destination potential preliminary adjustment signal DCOM can be accurately adjusted.

  Thus, according to the ink jet printer of the present embodiment, the drive waveform signal generation circuit 70 generates the drive waveform signal WCOM that serves as a reference for the signal for controlling the drive state of the actuator 22, and the generated drive waveform signal WCOM. Is amplified by the push-pull-connected charging transistor Tr1 and the discharging transistor Tr2 of the drive signal generating circuit 72 and the drive signal COM is output to preliminarily adjust the discharge destination potential from the drive signal generating circuit 72. A discharge destination potential preliminary adjustment waveform signal WDCOM is generated, the discharge destination potential preliminary adjustment waveform signal WDCOM is pulse-modulated by the discharge destination potential modulation circuit 25, and the pulse-modulated discharge destination potential modulation signal DPWM is discharged to the discharge destination potential. Pair of discharge destination potentials connected to the push-pull of the digital power amplifier 29 3, the power-amplified discharge destination potential preliminary adjustment signal DCOM is smoothed by the discharge destination potential smoothing filter 31 and output to the collector of the discharge transistor Tr 2 of the drive signal generation circuit 72. The potential difference between the pre-potential preliminary adjustment signal DCOM and the drive signal COM discharged from the charge / discharge actuator 22 can be reduced, and the power consumption can be reduced.

Further, if the discharge destination potential preliminary adjustment waveform signal WDCOM that adjusts the potential of the discharge destination potential preliminary adjustment signal DCOM by adjusting the voltage value of the discharge destination potential preliminary adjustment signal DCOM is generated, The accuracy can be improved and the power consumption can be further reduced.
If the discharge destination potential preliminary adjustment waveform signal WDCOM for adjusting the potential of the discharge destination potential preliminary adjustment signal DCOM is generated by adjusting the phase of the discharge destination potential preliminary adjustment signal DCOM, the accuracy of the drive signal COM It is possible to improve and further reduce power consumption.

  Next, a third embodiment of the ink jet printer of the present invention will be described with reference to FIG. The schematic configuration, control device, drive waveform signal and drive signal generation method, and actuator selection configuration of the ink jet printer of this embodiment are the same as those of the first embodiment. In the present embodiment, in addition to the charge source potential preliminary adjustment circuit 26 of the first embodiment, the discharge destination potential preliminary adjustment circuit 27 of the second embodiment is also provided. In addition, since those structures and functions are the same as those of the first embodiment and the second embodiment, respectively, the same reference numerals are given to the same structures, and the detailed description thereof is omitted.

In this embodiment, the potential of the charging source potential preliminary adjustment signal CCOM supplied to the collector of the charging transistor Tr1 of the driving signal generation circuit 72 is driven by appropriately setting the charging source potential preliminary adjustment waveform signal WCCOM. The discharge destination potential supplied to the collector of the discharge transistor Tr2 of the drive signal generation circuit 72 is adjusted by setting the discharge destination potential preliminary adjustment waveform signal WDCOM to be slightly higher than the potential of the signal COM. Adjustment is made so that the potential of the preliminary adjustment signal DCOM is slightly lower than the potential of the drive signal COM. Among them, there are two methods for adjusting the potential of the charging source potential preliminary adjustment signal CCOM. For example, the one shown in FIG. 14a is a method in which the voltage value of the charging source potential preliminary adjustment signal CCOM is slightly lower than the potential of the drive signal COM. FIG. 14b shows that the potential of the charging source potential preliminary adjustment signal CCOM is changed to the driving signal by making the phase of the charging source potential preliminary adjustment signal CCOM earlier than that of the driving signal COM. It was adjusted so as to be slightly higher than the potential. There are also two methods for adjusting the potential of the discharge destination potential preliminary adjustment signal DCOM. For example, the one shown in FIG. 14a is that the voltage value of the discharge destination potential preliminary adjustment signal DCOM is slightly smaller than the potential of the drive signal COM. In FIG. 14b, the potential of the discharge destination potential preliminary adjustment signal DCOM is made earlier than that of the drive signal COM, so that the potential of the discharge destination potential preliminary adjustment signal DCOM is changed to that of the drive signal. It is adjusted to be slightly lower than the potential.

  In this embodiment, the shaded area in FIGS. 14a and 14b corresponds to power consumption. In the present embodiment, the potential of the charge source potential preliminary adjustment signal CCOM supplied to the collector of the charging transistor Tr1 of the drive signal generation circuit 72 is adjusted to be slightly higher than the potential of the drive signal COM. Is adjusted so that the potential of the discharge destination potential preliminary adjustment signal DCOM supplied to the collector of the discharge transistor Tr2 of the drive signal generation circuit 72 is slightly lower than the potential of the drive signal COM. Therefore, power consumption due to the potential difference between the two is small. Therefore, in this embodiment, since power consumption can be reduced and the amount of heat generated can be reduced as compared with the conventional ink jet printer, no countermeasure is required. The charge source potential preliminary adjustment signal CCOM supplied to the collector of the charge transistor Tr1 of the drive signal generating circuit 72 is amplified by the charge source potential digital power amplifier 28 including the charge source potential transistor pair 32 for preliminary adjustment. As a result, the potential of the charge source potential preliminary adjustment signal CCOM can be accurately adjusted, and the discharge destination potential preliminary adjustment signal DCOM supplied to the collector of the discharge transistor Tr2 of the drive signal generation circuit 72 is changed to the discharge destination potential. The potential of the discharge destination potential preliminary adjustment signal DCOM can be accurately adjusted by amplifying the power with the discharge destination potential digital power amplifier 29 including the transistor pair 33 and performing preliminary adjustment.

  Thus, according to the ink jet printer of the present embodiment, the drive waveform signal generation circuit 70 generates the drive waveform signal WCOM that serves as a reference for the signal for controlling the drive state of the actuator 22, and the generated drive waveform signal WCOM. Is amplified by the push-pull-connected charging transistor Tr1 and the discharging transistor Tr2 of the drive signal generation circuit 72 and the drive signal COM is output to preliminarily adjust the charge source potential to the drive signal generation circuit 72. A charging source potential preliminary adjustment waveform signal WCCOM is generated, the charging source potential preliminary adjustment waveform signal WCCOM is pulse-modulated by the charging source potential modulation means 24, and the pulse-modulated charging source potential modulation signal CPWM is used as the charging source potential. Source pair transistor 3 for push-pull connection of digital power amplifier 28 for power supply The charge source potential preliminary adjustment signal CCOM amplified by the power source is smoothed by the charge source potential smoothing filter 30 and output to the collector of the charge transistor Tr1 of the drive signal generation circuit 72, and the drive signal generation circuit 72, a discharge destination potential preliminary adjustment waveform signal WDCOM for preliminarily adjusting the potential of the discharge destination from 72 is generated, and this discharge destination potential preliminary adjustment waveform signal WDCOM is pulse-modulated by the discharge destination potential modulation circuit 25. The modulated discharge destination potential modulation signal DPWM is power-amplified by the push-pull connected discharge destination potential transistor pair 33 of the discharge destination potential digital power amplifier 29, and the power-amplified discharge destination potential preliminary adjustment signal DCOM is obtained. The collector of the discharge transistor Tr2 of the drive signal generation circuit 72 is smoothed by the discharge destination potential smoothing filter 31. Therefore, the potential difference between the charge source potential preliminary adjustment signal CCOM and the drive signal COM that charges the charge / discharge actuator 22 can be reduced, and the discharge destination potential preliminary adjustment signal DCOM and the charge / discharge actuator 22 The potential difference with the drive signal COM to be discharged can be reduced, and the power consumption can be reduced.

Further, by adjusting the voltage value of the charging source potential preliminary adjustment signal CCOM, a charging source potential preliminary adjustment waveform signal WCCOM for adjusting the potential of the charging source potential preliminary adjustment signal CCOM is generated, and the discharge destination potential preliminary adjustment signal DCOM. By generating the discharge destination potential preliminary adjustment waveform signal WDCOM that adjusts the potential of the discharge destination potential preliminary adjustment signal DCOM by adjusting the voltage value of the drive signal COM, the accuracy of the drive signal COM can be improved and further power consumption can be reduced. Reduction is possible.

  Further, by adjusting the phase of the charging source potential preliminary adjustment signal CCOM, a charging source potential preliminary adjustment waveform signal WCCOM for adjusting the potential of the charging source potential preliminary adjustment signal CCOM is generated, and the discharge destination potential preliminary adjustment signal DCOM If the discharge destination potential preliminary adjustment waveform signal WDCOM for adjusting the potential of the discharge destination potential preliminary adjustment signal DCOM is generated by adjusting the phase, the accuracy of the drive signal COM can be improved and the power consumption can be further reduced. It becomes possible.

  Next, a fourth embodiment of the ink jet printer of the present invention will be described with reference to FIG. The schematic configuration, control device, drive waveform signal and drive signal generation method, and actuator selection configuration of the ink jet printer of this embodiment are the same as those of the first embodiment. In the present embodiment, a charge source and discharge destination potential preliminary adjustment circuit 23 is provided in place of the charge source potential preliminary adjustment circuit 26 of the first embodiment. The charge source and discharge destination potential preliminary adjustment circuit 23 is connected to the collector of the charge transistor Tr1 of the drive signal generation circuit 72 via the first rectifier D1, and preliminarily adjusts the original potential charged in the charge transistor Tr1. At the same time, it is also connected to the collector of the discharge transistor Tr2 of the drive signal generation circuit 72 via the second rectifier D2, and preliminarily adjusts the potential to be discharged from the discharge transistor Tr2.

  For example, the charge source and discharge destination potential preliminary adjustment circuit 23 performs pulse modulation on the charge source and discharge destination potential preliminary adjustment waveform signal WCDCOM generated by the potential preliminary adjustment waveform signal generation circuit 71 in the same manner as the drive waveform signal WCOM described above. A charge source and discharge destination potential modulation circuit 35 that performs power amplification of the charge source and discharge destination potential modulation signal CDPWM pulse-modulated by the charge source and discharge destination potential modulation circuit 35. For charging the drive signal generation circuit 72 by smoothing the digital power amplifier, so-called class D amplifier 36, and the charge source and discharge destination potential preliminary adjustment signal CDCOM amplified by the charge source and discharge destination potential digital power amplifier 36. Smoothing filter for charging source and discharging destination potential output to collector of transistor Tr1 and collector of discharging transistor Tr2 Configured with 8.

  The charge source and discharge destination potential modulation circuit 35 that performs pulse modulation of the charge source and discharge destination potential preliminary adjustment waveform signal WCDCOM, as in the case of the charge source potential modulation circuit 24 of the first embodiment, A width modulation (PWM) circuit was used. In addition, the charging source and discharging destination potential digital power amplifier, so-called class D amplifier 36, is similar to the charging source potential digital power amplifier 29 of the first embodiment, and includes two MOSFETs TrP for substantially amplifying power. Based on the charge source and discharge destination potential modulation circuit 35 from the charge source and discharge destination potential modulation circuit 35, the gates of the MOSFETs TrP and TrN And a gate driver circuit 34 for adjusting the inter-source signals GP and GN. Similarly to the charge source potential smoothing filter 30 of the first embodiment, the charge source and discharge destination potential smoothing filter 38 is, for example, a primary LC low-pass (low level) composed of a combination of one coil L and one capacitor C. It consists of a bandpass filter.

In the present embodiment, by appropriately setting the charge source and discharge destination potential preliminary adjustment waveform signal WCDCOM, the charge source supplied to the collector of the charge transistor Tr1 of the drive signal generation circuit 72 when charging the actuator and The potential of the discharge destination potential preliminary adjustment signal CDCOM is adjusted to be slightly higher than the potential of the drive signal COM, and the charge source supplied to the collector of the discharge transistor Tr2 of the drive signal generation circuit 72 when discharging from the actuator and The potential of the discharge destination potential preliminary adjustment signal CDCOM is adjusted to be slightly lower than the potential of the drive signal COM. There are two kinds of methods for adjusting the potentials of the charge source and discharge destination potential preliminary adjustment signal CDCOM. For example, the one shown in FIG. 14A uses the voltage value itself of the charge source and discharge destination potential preliminary adjustment signal CDCOM as the drive signal COM. 14b is adjusted by making the phase of the charging source and discharging destination preliminary adjustment signal CDCOM earlier than that of the driving signal COM. The source and destination potential preliminary adjustment signal CDCOM is adjusted so that it is slightly higher or lower than the potential of the drive signal.

  In this embodiment, the shaded area in FIGS. 14a and 14b corresponds to power consumption. In the present embodiment, the potential of the charge source and discharge destination potential preliminary adjustment signal CDCOM supplied to the collector of the charging transistor Tr1 of the drive signal generation circuit 72 is adjusted to be slightly higher than the potential of the drive signal COM. Therefore, the power consumption due to the potential difference between the two is small, and at the same time, the potential of the charge source and destination potential preliminary adjustment signal CDCOM supplied to the collector of the discharge transistor Tr2 of the drive signal generation circuit 72 is slightly lower than the potential of the drive signal COM. Therefore, the power consumption due to the potential difference between the two is small. Therefore, in this embodiment, since power consumption can be reduced and the amount of heat generated can be reduced as compared with the conventional ink jet printer, no countermeasure is required. The charge source and discharge destination potential preliminary adjustment signal CDCOM supplied to the collector of the charge transistor Tr1 and the collector of the discharge transistor Tr2 of the drive signal generation circuit 72 is a charge source composed of a charge source and discharge destination potential transistor pair 37. Further, the potential of the charge source and discharge destination potential preliminary adjustment signal CDCOM can be adjusted accurately by performing power amplification and preliminary adjustment by the discharge destination potential digital power amplifier 36.

  Thus, according to the ink jet printer of the present embodiment, the drive waveform signal generation circuit 70 generates the drive waveform signal WCOM that serves as a reference for the signal for controlling the drive state of the actuator 22, and the generated drive waveform signal WCOM. Is amplified by the push-pull-connected charging transistor Tr1 and discharging transistor Tr2 of the driving signal generating circuit 72 and the driving signal COM is output, the charging source potential and the discharging destination potential to the driving signal generating circuit 72 are A charge source and discharge destination potential preliminary adjustment waveform signal WCDCOM for preliminary adjustment is generated, and the charge source and discharge destination potential preliminary adjustment waveform signal WCDCOM is pulse-modulated by the charge source and discharge destination potential modulation circuit 35, and this pulse The modulated charge source and discharge destination potential modulation signal CDPWM is used as the charge source and discharge destination potential data. The power source is amplified by the push-pull connected charge source and discharge destination potential transistor pair 37 of the power amplifier 36, and the power amplified charge source and discharge destination potential preliminary adjustment signal CDCOM is supplied to the charge source and discharge destination potential smoothing filter. Since the output is supplied to the collector of the charging transistor Tr1 and the collector of the discharging transistor Tr2 of the drive signal generation circuit 72 after being smoothed by 38, the charge source / discharge destination potential preliminary adjustment signal CDCOM and the charge / discharge actuator 22 are charged / discharged. The potential difference from the drive signal COM to be reduced can be reduced, and the power consumption can be reduced.

Further, by adjusting the voltage value of the charge source and discharge destination potential preliminary adjustment signal CDCOM, a charge source and discharge destination potential preliminary adjustment waveform signal WCDCOM for adjusting the potential of the charge source and discharge destination potential preliminary adjustment signal CDCOM is generated. As a result, it is possible to improve the accuracy of the drive signal COM and further reduce power consumption.
In addition, by adjusting the phase of the charge source and discharge destination potential preliminary adjustment signal CDCOM, a charge source and discharge destination potential preliminary adjustment waveform signal WCDCOM for adjusting the potential of the charge source and discharge destination potential preliminary adjustment signal CDCOM is generated. Then, the accuracy of the drive signal COM can be improved and the power consumption can be further reduced.

In the above embodiment, only the example in which the liquid ejection apparatus of the present invention is applied to a so-called line head type ink jet printer has been described in detail. However, the liquid ejection apparatus of the present invention can be of any type including a multi-pass type printer. It can be applied to an inkjet printer.
Moreover, in the said embodiment, although the liquid discharge apparatus of this invention was actualized to the inkjet-type printing apparatus, it is not restricted to this, The liquid of other liquids other than ink (The particle | grains of a functional material are disperse | distributed besides a liquid) It is also possible to embody the present invention in a liquid ejecting apparatus that ejects or ejects a fluid other than a liquid (including a fluid such as a liquid or gel) or a fluid other than a liquid (such as a solid that can be ejected as a fluid). For example, a liquid material ejecting apparatus that ejects a liquid material that contains materials such as electrode materials and color materials used in the manufacture of liquid crystal displays, EL (electroluminescence) displays, surface-emitting displays, and color filters in a dispersed or dissolved form. Further, it may be a liquid ejecting apparatus for ejecting a bio-organic material used for biochip manufacturing, or a liquid ejecting apparatus for ejecting a liquid as a sample used as a precision pipette. In addition, a transparent resin liquid such as UV curable resin for forming a liquid ejecting device that ejects lubricating oil pinpoint to precision machines such as watches and cameras, and a micro hemispherical lens (optical lens) used for optical communication elements. For example, a liquid discharge device that discharges a liquid onto a substrate, a liquid discharge device that discharges an etching solution such as acid or alkali to etch the substrate, a fluid discharge device that discharges gel, and a powder such as toner It may be a fluid discharge type recording apparatus that discharges a solid. The present invention can be applied to any one of these discharge devices.

  1 is a print medium, 2 is a first inkjet head, 3 is a second inkjet head, 4 is a first transport unit, 5 is a second transport unit, 6 is a first transport belt, 7 is a second transport belt, and 8R and 8L. Is a driving roller, 9R and 9L are first driven rollers, 10R and 10L are second driven rollers, 11R and 11L are electric motors, 22 is an actuator, 23 is a charging source and discharging destination potential preliminary adjustment circuit, and 24 is a charging source potential. Modulation circuit, 25 is a discharge destination potential modulation circuit, 26 is a charge source potential preliminary adjustment circuit, 27 is a discharge destination potential preliminary adjustment circuit, 28 is a charge source potential digital power amplifier, 29 is a discharge destination potential digital power amplifier, 30 Is a charge source potential smoothing filter, 31 is a discharge destination potential smoothing filter, 32 is a charge source potential transistor pair, 33 is a discharge destination potential transistor pair, 34 is a gate driver circuit, 5 is a modulation circuit for charging source and discharging destination potential, 36 is a digital power amplifier for charging source and discharging destination potential, 37 is a transistor pair for charging source and discharging destination potential, 38 is a smoothing filter for charging source and discharging destination potential, 62 Is a control unit, 70 is a drive waveform signal generating circuit, 71 is a potential preliminary adjustment waveform signal generating circuit, Tr1 is a charging transistor, and Tr2 is a discharging transistor.

Claims (12)

  A plurality of nozzles provided in the liquid discharge head, a charge / discharge actuator provided corresponding to each nozzle, and a drive unit that applies a drive signal to the charge / discharge actuator of the nozzle that should discharge the liquid In the liquid ejecting apparatus, the drive waveform signal generating means for generating a drive waveform signal serving as a reference for a signal for controlling the drive state of the actuator, and the drive waveform signal generating means by a charge transistor and a discharge transistor connected in a push-pull manner A drive signal generating means for amplifying the drive waveform signal generated in step (a) and outputting a drive signal; and charging for generating a charge source potential preliminary adjustment waveform signal for preliminarily adjusting the charge source potential to the drive signal generating means An original potential pre-adjustment waveform signal generating means, and a charge source for the drive signal generating means and the drive signal generating means; and Charging source potential preliminary adjusting means for preliminarily adjusting the charging source potential to the drive signal generating means based on the charging source potential preliminary adjusting waveform signal generated by the charging source potential preliminary adjusting waveform signal generating means, and the charging The source potential preliminary adjustment means includes a charge source potential modulation means for pulse-modulating the charge source potential preliminary adjustment waveform signal generated by the charge source potential preliminary adjustment waveform signal generation means, and a charge source potential transistor connected in a push-pull manner. A charging source potential digital power amplifier that amplifies the power of the charging source potential modulation signal pulse-modulated by the charging source potential modulation means by a pair, and a charging source potential reserve amplified by the charging source potential digital power amplifier A liquid having a charging source potential smoothing filter for outputting an adjustment signal to a collector of a charging transistor of the driving signal generating means; Detection device.   The charging source potential preliminary adjustment waveform signal generating means generates a charging source potential preliminary adjustment waveform signal for adjusting the potential of the charging source potential preliminary adjustment signal by adjusting a voltage value of the charging source potential preliminary adjustment signal. The liquid ejecting apparatus according to claim 1, wherein:   The charging source potential preliminary adjustment waveform signal generating means generates a charging source potential preliminary adjustment waveform signal for adjusting the potential of the charging source potential preliminary adjustment signal by adjusting the phase of the charging source potential preliminary adjustment signal. The liquid ejection apparatus according to claim 1, wherein the liquid ejection apparatus is a liquid ejection device.   A plurality of nozzles provided in the liquid discharge head, a charge / discharge actuator provided corresponding to each nozzle, and a drive unit that applies a drive signal to the charge / discharge actuator of the nozzle that should discharge the liquid In the liquid ejecting apparatus, the drive waveform signal generating means for generating a drive waveform signal serving as a reference for a signal for controlling the drive state of the actuator, and the drive waveform signal generating means by a charge transistor and a discharge transistor connected in a push-pull manner Drive signal generation means for amplifying the drive waveform signal generated in step (a) and outputting a drive signal; and a discharge destination for generating a discharge destination potential preliminary adjustment waveform signal for preliminarily adjusting the potential of the discharge destination of the drive signal generation means A potential pre-adjustment waveform signal generating means, and a discharge destination from the drive signal generating means and the drive signal generating means; A discharge destination potential preliminary adjustment means for preliminarily adjusting a discharge destination potential from the drive signal generation means based on a discharge destination potential preliminary adjustment waveform signal generated by the discharge destination potential preliminary adjustment waveform signal generation means; The pre-potential pre-adjusting means includes a discharge pre-potential modulation means for pulse-modulating the discharge pre-potential pre-adjustment waveform signal generated by the discharge pre-potential pre-adjustment waveform signal generating means, and a push-pull connected discharge destination potential transistor A discharge destination potential digital power amplifier that amplifies the power of the modulation signal for discharge destination potential pulse-modulated by the discharge destination potential modulation means by a pair, and a discharge destination potential reserve amplified by the digital power amplifier for discharge destination potential A liquid having a discharge destination potential smoothing filter for outputting an adjustment signal to a collector of a discharge transistor of the drive signal generating means Ejection device.   The discharge destination potential preliminary adjustment waveform signal generating means generates a discharge destination potential preliminary adjustment waveform signal for adjusting a potential of the discharge destination potential preliminary adjustment signal by adjusting a voltage value of the discharge destination potential preliminary adjustment signal. The liquid discharge apparatus according to claim 4, wherein:   The discharge destination potential preliminary adjustment waveform signal generation means generates a discharge destination potential preliminary adjustment waveform signal that adjusts the potential of the discharge destination potential preliminary adjustment signal by adjusting the phase of the discharge destination potential preliminary adjustment signal. The liquid ejection device according to claim 4, wherein the liquid ejection device is a liquid ejection device.   A discharge destination potential preliminary adjustment waveform signal generating means for generating a discharge destination potential preliminary adjustment waveform signal for preliminarily adjusting the potential of the discharge destination of the drive signal generation means; a discharge destination from the drive signal generation means and the drive signal; A discharge destination that is disposed between the discharge means and the discharge destination potential preliminary adjustment waveform signal generated by the discharge destination potential preliminary adjustment waveform signal generation means and that preliminarily adjusts the discharge destination potential from the drive signal generation means. A potential pre-adjustment unit, the discharge destination potential pre-adjustment unit, the discharge destination potential pre-adjustment waveform signal generated by the discharge destination potential pre-adjustment waveform signal generation unit, a discharge destination potential modulation unit, Discharge destination potential digital that amplifies the power of the modulation signal for the discharge destination potential pulse-modulated by the discharge destination potential modulation means by the push-pull connected pair of discharge destination potential transistors. And a discharge destination potential smoothing filter that outputs a discharge destination potential preliminary adjustment signal amplified by the discharge destination potential digital power amplifier to the collector of the discharge transistor of the drive signal generating means. The liquid ejection apparatus according to claim 1, wherein the liquid ejection apparatus is a liquid ejection device.   The charging source potential preliminary adjustment waveform signal generating means generates a charging source potential preliminary adjustment waveform signal for adjusting the potential of the charging source potential preliminary adjustment signal by adjusting a voltage value of the charging source potential preliminary adjustment signal, The discharge destination potential preliminary adjustment waveform signal generating means generates a discharge destination potential preliminary adjustment waveform signal for adjusting a potential of the discharge destination potential preliminary adjustment signal by adjusting a voltage value of the discharge destination potential preliminary adjustment signal. The liquid discharge apparatus according to claim 7.   The charging source potential preliminary adjustment waveform signal generating means generates a charging source potential preliminary adjustment waveform signal for adjusting the potential of the charging source potential preliminary adjustment signal by adjusting the phase of the charging source potential preliminary adjustment signal, The discharge destination potential preliminary adjustment waveform signal generation means generates a discharge destination potential preliminary adjustment waveform signal that adjusts the potential of the discharge destination potential preliminary adjustment signal by adjusting the phase of the discharge destination potential preliminary adjustment signal. The liquid ejection device according to claim 7.   A plurality of nozzles provided in the liquid discharge head, a charge / discharge actuator provided corresponding to each nozzle, and a drive unit that applies a drive signal to the charge / discharge actuator of the nozzle that should discharge the liquid In the liquid ejecting apparatus, the drive waveform signal generating means for generating a drive waveform signal serving as a reference for a signal for controlling the drive state of the actuator, and the drive waveform signal generating means by a charge transistor and a discharge transistor connected in a push-pull manner A drive signal generating means for amplifying the drive waveform signal generated in step (a) to output a drive signal, and a charge source potential to the drive signal generating means and a discharge destination potential from the drive signal generating means Charging source and destination potential preliminary adjustment waveform signal generating means for generating a charging source and discharge destination potential preliminary adjustment waveform signal, and the drive signal A charging source that is disposed between a charging source to the generating unit and a discharging destination from the driving signal generating unit and the driving signal generating unit, and generated by the charging source and discharging destination potential pre-adjustment waveform signal generating unit, and A charge source and a discharge destination potential preliminary adjustment unit for preliminarily adjusting a charge source potential to the drive signal generation unit and a discharge destination potential from the drive signal generation unit based on a discharge destination potential preliminary adjustment waveform signal; The source and discharge destination potential preliminary adjustment means is a charge source and discharge destination potential modulation means for pulse-modulating the charge source and discharge destination potential preliminary adjustment waveform signal generated by the charge source and discharge destination potential preliminary adjustment waveform signal generation means. A charge source and discharge destination potential modulation signal pulse-modulated by the charge source and discharge destination potential modulation means by a push-pull connected charge source and discharge destination potential transistor pair Charge source and discharge destination potential digital power amplifiers for power amplification, and charge source and discharge destination potential preliminary adjustment signals amplified by the charge source and discharge destination potential digital power amplifiers as charging transistors of the drive signal generating means And a smoothing filter for a charge source and a discharge destination output to the collector of the discharge transistor and the collector of the discharge transistor.   The charging source and discharge destination potential preliminary adjustment waveform signal generating means adjusts the voltage value of the charging source and discharge destination potential preliminary adjustment signal to adjust the potential of the charging source and discharge destination potential preliminary adjustment signal. And a discharge destination potential pre-adjustment waveform signal.   The charging source and discharge destination potential preliminary adjustment waveform signal generating means adjusts the phase of the charging source and discharge destination potential preliminary adjustment signal to adjust the potential of the charging source and discharge destination potential preliminary adjustment signal, and The liquid discharge apparatus according to claim 10, wherein a discharge destination potential preliminary adjustment waveform signal is generated.

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