JP2010000730A - Inspection device for inkjet head, and inkjet recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inspection device for an inkjet head by which, concerning a simultaneous jetting number of a recording head which varies according to recorded data, an optimum correction amount can be set according to an individual difference among recording heads, an individual difference among recording devices and variation with passage of time, and to provide an inkjet recording device. <P>SOLUTION: In an inspection device for an inkjet head wherein a plurality of recording elements are arranged, the inspection device for the inkjet head is equipped with a drive energy measuring means for measuring minimum drive energy required for jetting, a simultaneous jetting number selecting means for selecting a simultaneous jetting number of recording elements connected to a common power wiring, and a correction amount calculating means for calculating an amount to correct drive energy required for jetting based on a result obtained by measuring the minimum drive energy. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to an ink jet head inspection method in which a plurality of recording elements are arranged, and an ink jet recording apparatus.

  An ink jet recording apparatus conventionally records on a recording medium (hereinafter, also simply referred to as “recording paper”) such as paper, cloth, plastic sheet, and OHP sheet, and can perform high-density and high-speed recording operations. Therefore, the ink jet recording apparatus is used as an output unit of an information processing system, for example, a printer as an output terminal of a copying machine, a facsimile, an electronic typewriter, a word processor, a workstation, or the like.

  Further, the ink jet recording apparatus is used and commercialized as a handy or portable printer provided in a personal computer, a host computer, an optical disc apparatus, a video apparatus or the like. In this case, the ink jet recording apparatus has a configuration corresponding to functions, usage patterns, and the like unique to these apparatuses.

  In general, an ink jet recording apparatus includes a carriage on which recording means (recording head) and an ink tank are mounted, a conveying means for conveying recording paper, and a control means for controlling these. A recording head that ejects ink droplets from a plurality of ejection ports is serially scanned in a direction (main scanning direction) substantially perpendicular to the conveyance direction (sub-scanning direction) of the recording paper. Recording is performed by intermittently conveying the recording paper by an amount equal to the recording width.

  This recording method is widely used as a quiet recording method in which ink is ejected onto a recording sheet in accordance with a recording signal and the running cost is low. In addition, a recording head in which a large number of nozzles that eject ink are linearly arranged in the sub-scanning direction is used, and the recording head scans the recording paper once, so that recording with a width corresponding to the number of nozzles is performed. Is done. For this reason, it is possible to increase the speed of the recording operation by increasing the number of nozzles of the recording head and increasing the scanning speed.

  Usually, the recording head is provided with ejection energy generating means such as heaters corresponding to each nozzle, and the electric power for driving these heaters is routed through wiring with relatively small capacity such as electrical contact pads from the printer body. Supplied. As a result, when the load of recorded data changes, the current value drawn from the line changes, and the voltage applied to each heater may change unexpectedly accordingly. For example, if many or all heaters are driven simultaneously, the voltage supplied to the printhead may drop due to parasitic effects, resulting in a lower voltage than when one or a few heaters are driven.

  In this way, in order to compensate for the drop in the voltage supplied to the recording head and to make the discharge energy constant regardless of the number of nozzles that discharge simultaneously (number of simultaneous discharges), the drive voltage or Adjust the drive pulse width.

  Usually, since the electrical characteristics are different for each print head, a drive pulse control table for determining a drive pulse using the number of simultaneous ejections and the characteristics of the print head as parameters is provided. An invention is known in which drive pulses are switched based on a drive pulse control table in accordance with the characteristics of the recording head and the number of simultaneous ejections (see, for example, Patent Document 1).

  However, when the drive pulse is controlled only by the characteristics of the recording head and the number of simultaneous ejections as described above, the following problem occurs.

  In general, in a long head having a large number of heaters, the heaters are grouped into several groups and are energized by one wiring in order to suppress the resistance value of the wiring and due to restrictions on the substrate area. In this case, even if the number of simultaneous discharges is the same, the amount of voltage drop in the current flow path varies depending on whether the heater to be driven is dispersed in each group or concentrated in a specific group. There is a problem that the voltage applied to each heater is different.

  Specifically, when the heaters to be driven are concentrated, the amount of voltage drop due to the in-head wiring portion increases, and the voltage applied to the heater further decreases. If such a phenomenon is not taken into account, there is a problem that the discharge energy by the heater cannot be obtained sufficiently, the discharge becomes unstable, and the discharge may not be performed.

  Next, this phenomenon will be described in detail.

  FIG. 7 is a schematic view showing an example of the electrical configuration of a conventional inkjet recording head PH1.

  The ink jet recording head PH1 of the conventional example has connection pads 1 and 2, a heater H, and a transistor T.

  The connection pad 1 is a pad connected to the power line of the printer main body. The connection pad 2 is a pad connected to the ground line of the printer body. The transistor T is turned on and off by a signal from a controller (not shown) to control the current to the heater.

  In the conventional example shown in FIG. 7, 256 heaters H are provided, and the heaters H are classified into drive segments SEG1 to SEG16. Each of the drive segments SEG1 to SEG16 is a group connected to a common wiring line every 16 segments.

  The four drive segments constitute a segment block. This segment block is a group of the four drive segments, and is a group connected to a common wiring line. Then, four segment blocks are gathered and connected to the connection pad 1 and the connection pad 2 through a common wiring line.

  Further, in the conventional example shown in FIG. 7, the symbols A, B, C are assigned in order from the connection pads at the intersections of the wirings, and the numbers 1, 2, 3,. ing. That is, common wiring lines C1 to C16 are connected to 16 heaters in the same drive segment, and common wiring lines B1 to B4 are connected to four drive segments in the same segment block. A common wiring line A is connected to the connection pads of the four segment blocks. Since the connection to the connection pad 2 is the same as the connection to the connection pad 1, the illustration is omitted.

  FIG. 8 is a timing chart in the case of driving the conventional ink jet recording head PH1.

  In FIG. 8, blocks 1 to 16 are time-divided groups that define heaters that are driven simultaneously in one column. Note that the one column is a unit for recording one column in the heater arrangement direction.

  Normally, in the multi-nozzle head configured as described above, in consideration of the capacity of the drive power supply on the main body side, within the same block, each drive segment is limited to drive only one heater, Only a maximum of 16 heaters are driven.

  Then, distributed driving and concentrated driving can be considered. For example, when the number of simultaneous ejections is 4, the distributed drive is to drive one heater in each drive segment of the four segment blocks B1 to B4. That is, one heater is driven by one block. The concentrated drive is to simultaneously drive four drive segments in one segment block.

  In this case, four lines between the intersections A and B are used in parallel during distributed driving, and only one line is used during centralized driving. Higher than voltage drop in distributed drive.

  Therefore, in the conventional driving pulse control method in which the pulse width (or voltage) is controlled by the number of simultaneous ejections, the ejection energy generated by the concentrated driving with a large voltage drop is smaller than the ejection energy generated by the distributed driving. Occurs.

  In order to solve the problem caused by the difference in applied energy caused by dispersion / concentration of driving, it is conceivable to provide a separate power line for each group and control based on the number of simultaneous ejections in the group. However, if this is implemented, the power supply wiring between the recording head and the apparatus main body becomes complicated, the size of the entire apparatus increases, and the cost increases.

  Further, if the drive pulse is set large in advance, sufficient ejection energy can be secured when the drive is concentrated. However, in this case, another problem arises in that an excessive voltage is applied to the heater driven when the number of simultaneous ejections is small, and the heater is damaged.

Based on the recording data, in the recording elements that are driven at a predetermined timing, the driving concentration to each group connected to the common power supply wiring is calculated, and according to the driving concentration, the parameter of the driving signal of the recording element Is known (see, for example, Patent Document 2).
Japanese Patent Laid-Open No. 9-11463 JP 2003-285442 A

  However, in the above-described conventional example, the correction amount for the simultaneous ejection number fluctuation is set using only the print head characteristics (characteristics mainly determined by the heater resistance value) as a parameter. Therefore, since the resistance value of each wiring part is not taken into account, the maximum amount in the design is used to calculate the amount of correction for fluctuations in the simultaneous discharge number so that discharge failure does not occur when the simultaneous discharge number increases. is doing.

  In the case where there are few recording elements that share a power source, the influence of the wiring resistance variation is relatively small. However, in recent years, as the length / density increases, and the number of recording elements increases, the head due to excess energy due to the difference between the resistance value serving as the base for the correction value calculation and the actual resistance value is increased. There is a problem that the life of the recording head is reduced due to the load.

  INDUSTRIAL APPLICABILITY The present invention relates to an ink jet head inspection apparatus and an ink jet which can set an optimum correction amount according to individual print head differences, individual print apparatus differences, and temporal variations with respect to the number of simultaneous discharges of a print head that changes according to print data. An object is to provide a recording apparatus.

The individual difference between the recording heads is a variation in the voltage drop in the wiring in the head, and the individual difference among the recording devices is a variation in the power supply and a variation in the voltage drop in the wiring between the power supply and the head.

According to the present invention, in a recording head inspection apparatus in which a plurality of recording elements are arranged, the driving energy measuring means for measuring the minimum driving energy required for ejection and the recording elements connected to a common power supply line are simultaneously used. An inspection apparatus for an inkjet head, comprising: a simultaneous discharge number selection unit that selects a discharge number; and a correction amount calculation unit that calculates an amount for correcting drive energy necessary for discharge based on a result of measuring a minimum drive energy. .

  According to the present invention, it is possible to set an optimal correction amount with respect to individual print head individual differences, individual print apparatus differences, and temporal changes with respect to the simultaneous ejection number of the print head that changes according to print data. There is an effect.

According to the present invention, it is possible to provide stable ejection and increase the life of a recording head for various recording data in which the number of simultaneous ejections sequentially varies.

  The best mode for carrying out the invention is the following embodiment.

  First, in this specification, “recording” is not limited to forming significant information such as characters and graphics. In other words, “recording” forms images, patterns, patterns, etc. on a wide range of recording media, regardless of whether they are significant or insignificant, and whether they are manifested so that humans can perceive them visually. Or processing of the medium. Note that the above recording may be referred to as printing.

  The “recording medium” is not limited to paper used in general recording apparatuses, but is widely capable of receiving ink, such as cloth, plastic film, metal plate, glass, ceramics, wood, and leather.

  Furthermore, “ink” is applied onto the recording medium, thereby forming an image, pattern, pattern, etc., processing the recording medium, or processing the ink (for example, coagulation of the colorant in the ink applied to the recording medium). Or a liquid that can be subjected to insolubilization. The “ink” is sometimes referred to as “liquid” and should be interpreted widely as in the definition of “recording”.

<Outline of recording device>
FIG. 1 is a schematic diagram showing the entirety of an ink jet recording apparatus R1 that is Embodiment 1 of the present invention.

  The ink jet recording apparatus R1 includes a paper feed roller 1, a main scanning guide 3, a carriage 4, a recording head 5, and a platen 6.

  The paper feed roller 1 sandwiches the recording medium 2 with a pair of rollers and rotates to move the recording medium 2 in the sub-scanning direction.

  The recording head 5 includes an ejection port on the surface facing the platen 6. The recording head 5 is detachably attached to the carriage 4, and the carriage moves along the main scanning guide 3 by carriage driving means (not shown), thereby scanning the recording medium 2 (hereinafter, “ Ink droplets are ejected while “main scanning”. The recording head 5 is coupled to an ink supply device (not shown) and is supplied with ink.

  The platen 6 is provided below the recording head 5, and the recording medium 2 is positioned between the platen and the recording head 5 during recording. Further, by being held by the platen 6, the gap between the recording medium 2 and the recording head 5 is held so as to be appropriate.

  Although not shown in FIG. 1, the ink jet recording apparatus R1 includes a recording medium supply unit that supplies the recording medium 2 to the paper feed roller, a recovery unit that appropriately maintains the state around the ejection port of the recording head 5, Recording medium discharge means for taking out the recording medium 2 after recording.

  In addition, it is preferable to add a recovery means for recovering the recording head 5, a preliminary auxiliary means, and the like as the ink jet recording apparatus R1, since the effects of the invention are further stabilized. Specific examples of these auxiliary means include a capping means for the recording head 5, a cleaning means, a pressurizing / suctioning means, and a preliminary discharge mode in which discharge is performed separately from recording.

  Next, a recording operation in the inkjet recording apparatus R1 will be described.

  First, when a recording start command signal is input to the inkjet recording apparatus R1, the leading end of the recording medium 2 is moved from the upper right direction in FIG. 1 to the position of the paper feed roller 1 by a recording medium supply unit (not shown). Supplied until it comes. Thereafter, the paper feed roller 1 feeds the recording medium 2 according to the recording signal so that the recording head 5 is positioned at the printing start position on the recording medium 2. Subsequently, printing is performed by spraying ink droplets onto the recording medium 2 while the carriage 4 and the recording head 5 perform main scanning.

  Thereafter, the paper feed roller 1 feeds the recording medium 2 by a predetermined amount (hereinafter, this operation is referred to as “sub-scanning”), and the carriage 4 and the recording head 5 perform main scanning again, while the ink is transferred onto the recording medium 2. Spray the drops. After recording on the recording medium 2 by repeating the sub-scanning and main scanning, the recording medium 2 is discharged in the lower left direction in FIG. Note that paper is often used as the recording medium 2, but other materials may be used. Further, in the case of an OHP sheet, a compact disk, and a DNA chip manufacturing apparatus and a display manufacturing apparatus using ink jet, a material made of a material suitable for each is used as the recording medium 2.

<Description of control configuration>
Next, a control configuration for controlling the recording of the inkjet recording apparatus R1 will be described.

  FIG. 2 is a block diagram illustrating a configuration of the control circuit 10 of the inkjet recording apparatus R1.

  The control circuit 10 includes an MPU 11, a ROM 12, a DRAM 13, and a gate array 14.

  The interface 20 inputs a recording signal. The ROM 12 stores a control program executed by the MPU 11. The DRAM 13 stores various data (such as the recording signal and recording data supplied to the head).

  The gate array 14 controls supply of recording data to the recording head 5 and also controls data transfer with the interface 20, MPU 11, and DRAM 13.

  The transport motor 32 is a motor for transporting the recording medium 2. The carrier motor 33 is a motor for transporting the recording head 5.

  The head driver D1 drives the recording head 5. The motor driver D <b> 2 is a driver that drives the transport motor 32. The motor driver D3 is a driver that drives the carrier motor 33.

  The MPU 11 is an example of a driving energy measuring unit that measures the minimum driving energy necessary for ejection, and is an example of a simultaneous ejection number selection unit that selects the number of simultaneous ejections of the recording elements connected to the common power supply wiring. . The MPU 11 is an example of a correction amount calculation unit that calculates an amount for correcting the drive energy required for discharge based on the result of measuring the minimum drive energy by changing the number of simultaneous discharges by the simultaneous discharge number selection unit. is there. Furthermore, the MPU 11 is an example of a control unit that controls the amount of drive energy applied to the recording element based on the correction amount.

  Next, the operation of the control circuit 10 will be described.

  When a recording signal enters the interface 20, the recording signal is converted into recording data for printing between the gate array 14 and the MPU 11. Then, the motor drivers D2 and D3 are driven, and the recording head 5 is driven according to the recording data sent to the head driver D1 to perform recording.

  Here, the control program executed by the MPU 11 is stored in the ROM 12, but an erasable / writable storage medium such as an EEPROM is added so that the control program can be changed from a host computer connected to the inkjet recording apparatus R1. It may be.

<Method for Detecting Drive Energy Threshold in Example 1>
FIG. 3 is an enlarged perspective view showing the ejection state detection unit 40 in the inkjet recording apparatus R1.

  The photosensor is a transmissive photointerrupter that is installed at a position facing the nozzle row of the recording head 5 and directly optically detects ink droplets ejected by the nozzles of the recording head 5. The photosensor includes a light emitting element 45 and a light receiving element 46. The light emitting element 45 uses an infrared LED, and has a light emitting portion that integrally projects a lens on its light emitting surface and can project approximately parallel light toward the light receiving element 46. The light receiving element 46 is formed by a light receiving portion using a phototransistor.

  By passing the ink droplet through this detection range, the ink droplet blocks the light from the light emitting element 45 and reduces the amount of light to the light receiving element 46, and the output of the phototransistor provided in the light receiving portion changes. Note that as the number of nozzles provided in the recording head 5 increases, it is necessary to detect ink droplets relatively stably over a long distance. It is advantageous to use an easy light source.

  Therefore, in addition to the LED, a semiconductor laser or other laser light source may be used. Further, it is desirable to use a photosensor having excellent light speed response such as a PIN silicon photodiode.

  When detecting the ejection state, a carriage drive unit is controlled from a recording control unit (not shown) so that the first detection chip nozzle row in the recording head 5 is positioned on the optical axis 47 of the photosensor. .

  Subsequently, the recording controller sequentially sends drive pulses to the predetermined nozzles of the chip to eject ink, and the ejected ink droplet crosses the optical axis 47. By monitoring the output of the phototransistor at this time, the recording control unit can know the timing at which the ejected ink droplet crosses the optical axis.

  That is, the ejection state of each nozzle is detected by measuring the drive pulse application time and the time until the ink droplet ejected by the drive signal crosses the optical axis. When performing the above detection, the drive energy to be supplied can be gradually decreased, and the drive energy threshold necessary for ink ejection can be determined by finally reaching the non-ejection state.

  In the above detection, in order to avoid an initial ejection failure of the head, it is desirable to perform preliminary ejection with a reliably ejected pulse immediately before the pulse when ejection is stopped. When the drive energy to be supplied is switched, the present invention is not limited to the above, and the drive energy may be gradually increased so as to reach the discharge from the non-discharge state.

  In the above embodiment, when detecting in a short time without bothering the user, the driving energy threshold value detection by the optical detection means is adopted, but it is not necessary to be limited to this. For example, a method may be employed in which a recording medium for detection is prepared, the drive energy to be supplied is gradually switched, the ink is actually discharged onto the medium, and the print result is detected by a sensor.

<Control method for simultaneous discharge number fluctuation>
The recording data input from the host computer is received, and the received recording data is stored in the data buffer by the recording device. Since this example is a serial type printing apparatus, data is received in units of one scanning line. Next, the recording data stored in the data buffer is expanded in the expansion RAM. Then, the number of simultaneous ejections (referred to as the number of individual simultaneous ejections) is counted in a printing element having a common power source, and a drive pulse width is determined based on a preset correction table to drive.

  Next, a basic operation for calculating the drive energy correction amount in the first embodiment will be described.

  FIG. 4 is a flowchart illustrating a basic operation for calculating a drive energy correction amount in the first embodiment.

  Here, since the resistance difference (between B1 and B4) for each divided wiring shown in FIG. 7 is not taken into consideration, it is necessary to consider the margin when designing the drive energy for actual recording.

  The basic operation for calculating the drive energy correction amount is roughly divided into the following two steps. The first step is a step of measuring the minimum drive energy Pth1 when heated for each single nozzle, and the latter half step is a step of measuring the minimum drive energy Pth2 during simultaneous heating of all nozzles.

  In S1, a drive energy measurement voltage is set as the drive voltage. The set drive voltage is not particularly limited, but is converted for recording by setting the drive voltage Vop at the time of recording to a value V (Vop / K) divided by a margin (K) at the time of designing the drive energy. This is desirable because it does not require a process to be performed. When the recording is performed on the recording apparatus, the recording may be performed with the driving voltage Vop during recording, and the recording may be corrected by the driving energy design margin during recording.

  In S2, the initial drive pulse width is set, and in subsequent S3 to S5, the drive energy to discharge for each individual nozzle is calculated while sequentially decreasing the drive pulse width. In step S6, when all the nozzles are completed, the nozzle that is most likely to be ejected and the minimum drive energy Pth1 are calculated in the head.

  From S7, the process proceeds to the latter half of the inspection, and in the state where all the nozzles of the recording head 5 are heated, the minimum drive energy is measured again while decreasing the drive pulse width sequentially (S6 to S11). At this time, paying attention to the most easily ejected nozzle determined in S6, the minimum drive energy Pth2 of the nozzle is measured.

  After completing the measurement of Pth1 / Pth2, in S12, the drive energy correction amount between single nozzle discharge / all nozzle discharge (maximum correction amount with respect to fluctuations in the number of simultaneous discharges) “Pth1-Pth2” is calculated based on the measurement result. To do.

  After inspecting the correction amount, the inspected correction amount is written in the recording head recording memory unit, and a correction amount table is created based on the written correction amount when the recording apparatus is mounted. In the recording apparatus, it is desirable to operate while regularly inspecting and updating the recording apparatus in order to optimize the correction amount in consideration of the individual difference / change over time.

  In the first embodiment, the correction amount is calculated based on the difference between the driving energy of the single nozzle and the driving energy of all the nozzles. However, the present invention is not limited to this. The correction amount may be measured by setting a step.

  In the first embodiment, the nozzle that is most likely to be ejected is specified as the correction amount calculation target nozzle. However, the present invention is not limited to this, and an average of a plurality of nozzles may be used. In this case, however, attention must be paid to the detection method.

According to the optical detection method of the first embodiment, when a plurality of nozzles discharge, it is not possible to determine which nozzle is discharging. Therefore, when performing the detection method described above, it is necessary to turn off the heat of the nozzle that discharges with driving energy lower than that of the measurement target. In addition, it is necessary to employ another detection method that can determine the presence or absence of ejection for individual nozzles.

  The second embodiment of the present invention is an embodiment in which the driving energy correction amount is calculated including the resistance difference (between B1 and B4) for each conventional divided wiring shown in FIG.

  FIG. 5 is a flowchart showing the operation of the second embodiment of the present invention.

  This flowchart is roughly divided into a flowchart (basic portion A shown in FIG. 4) showing a basic operation for calculating a correction amount and a divided wiring group selection unit measured in the flowchart.

  In S22, the divided wiring group Gr1 is selected. Subsequently, in S23, the correction amount of the recording element belonging to the B1 group is calculated. In S24 / S25, the group selection is switched, and the correction amount for each group is sequentially calculated.

  When the measurement of all groups is completed, the maximum correction amount value in all groups is set as the correction value of the recording head 5 in S26.

  According to the second embodiment, it can be considerably optimized according to the wiring resistance value of the recording head 5. However, the difference between the maximum correction value and the correction value for each group remains as an error.

A case where drive control can be performed for each divided wiring will be described in a third embodiment.

  The third embodiment of the present invention is the same as the second embodiment until the correction amount is measured for each group. Finally, individual drive control is performed for each divided wiring section (B1 to B4 in FIG. 7). It is the Example which added the operation | movement which measures the correction amount for this.

  FIG. 6 is a flowchart showing the operation of the third embodiment of the present invention.

  S31 to S35 are the same as S21 to S25 of the second embodiment, and measure the correction amount for each group. After S36, the voltage drop contribution between the wirings A / B shown in FIG. 7 is calculated in order to enable individual control for each group.

  In S36, for example, the nozzle X that is the most easily ejected nozzle belonging to B1 is selected. In S38, the minimum drive energy Pth3 related to the selected nozzle X is measured while heating all the printing elements belonging to a group different from B1.

  By comparing the nozzle with Pth1 (minimum drive energy with a single nozzle) measured in S32 to S35, the voltage drop contribution of the portion corresponding to the wiring A shown in FIG. 7 is calculated. Further, the correction amount (voltage drop) contribution degree of the wiring B to which the nozzle belongs is calculated by comparing Pth2 (total discharge within the same group) and Pth3.

  Thereby, it is possible to perform optimal control in consideration of the resistance difference of the divided wiring B with respect to the simultaneous ejection number variation.

  In the first to third embodiments, when the supply drive energy is switched, the drive voltage V is fixed and the pulse width of the drive pulse applied to the recording element is changed (gradually decreased). It may be fixed and the drive voltage V may be changed.

In the third embodiment, when the minimum discharge energy is measured, the energy is gradually decreased from the initial driving energy and measured. However, the present invention is not limited to this, and the energy may be gradually increased and measured. Good.

  The above embodiment is a serial type ink jet recording apparatus R1.

  Embodiment 4 of the present invention is an embodiment applied to any type of recording apparatus that performs recording using a recording head 5 in which a plurality of recording elements are arranged.

The configuration of the recording element and its driving method are not particularly limited.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram illustrating the entirety of an inkjet recording apparatus R1 that is Embodiment 1 of the present invention. It is a block diagram which shows the structure of the control circuit 10 of inkjet recording device R1. It is a perspective view which expands and shows the discharge state detection part 40 in inkjet recording device R1. 5 is a flowchart illustrating a basic operation for calculating a drive energy correction amount in the first embodiment. It is a flowchart which shows operation | movement of Example 2 of this invention. It is a flowchart which shows operation | movement of Example 3 of this invention. It is the schematic which shows the example of the electrical structure of the inkjet recording head PH1 of a prior art example. It is a timing diagram in the case of driving the inkjet recording head PH1 of the conventional example.

Explanation of symbols

R1 ... inkjet recording apparatus,
5 ... Recording head,
10: control circuit,
11 ... MPU,
12 ... ROM,
13 ... DRAM,
14 ... Gate array,
45. Light emitting element,
46: Light receiving element.

Claims (13)

In a recording head inspection apparatus in which a plurality of recording elements are arranged,
Driving energy measuring means for measuring the minimum driving energy required for discharge;
Simultaneous discharge number selection means for selecting the number of simultaneous discharges of the recording elements connected to the common power supply wiring;
A correction amount calculating means for calculating an amount for correcting drive energy required for discharge based on a result of measuring the minimum drive energy by changing the number of simultaneous discharges by the simultaneous discharge number selecting means;
An inspection apparatus for an ink jet head, comprising: In claim 1,
An ink jet head characterized in that the recording elements connected to the common power supply wiring are bundled into a plurality of groups in the recording head, and the drive energy is measured and the correction amount is calculated for each group. Inspection equipment. In claim 1 or claim 2,
An inspection apparatus for an ink jet head, wherein the correction amount is stored in a memory section of the recording head. In any one of Claims 1-3,
An inspection apparatus for an ink jet head, wherein the drive energy measuring means is means having optical detection means having a light emitting element and a light receiving element. In any one of Claims 1-4,
An inspection apparatus for an ink jet head, wherein the drive energy measuring means is means for measuring energy of a recording element ejected with the lowest driving energy among the recording elements connected to a common power supply wiring. In a recording apparatus for recording by a recording head in which a plurality of recording elements are arranged,
Driving energy measuring means for measuring the minimum driving energy required for discharge;
Simultaneous discharge number selection means for selecting the number of simultaneous discharges of the recording elements connected to the common power supply wiring;
A correction amount calculating means for calculating a drive energy correction amount based on a result of measuring the minimum drive energy by the simultaneous discharge number selecting means changing the simultaneous discharge number;
Control means for controlling the amount of drive energy applied to the recording element based on the correction amount;
An ink jet recording apparatus comprising: In claim 6,
Recording elements connected to the common power supply wiring are bundled into a plurality of groups in a recording head, and the drive energy measurement and the correction amount calculation are performed for each group. apparatus. In claim 6 or claim 7,
The ink jet recording apparatus according to claim 1, wherein the driving energy measuring means is a means for measuring using an optical detecting means having a light emitting element and a light receiving element. In any one of Claims 6-8,
The ink jet recording apparatus, wherein the driving energy measuring means is means for measuring energy of a recording element ejected with the lowest driving energy among the recording elements connected to a common power supply wiring. In any one of Claims 6-9,
The ink jet recording apparatus, wherein the control means is means for controlling a driving energy amount applied to the recording element by a driving pulse. In any one of Claims 6-9,
The ink jet recording apparatus, wherein the control means is means for controlling the amount of energy applied to the recording element by a driving voltage. In a control method of an inspection apparatus for a recording head in which a plurality of recording elements are arranged,
A driving energy measurement process for measuring the minimum driving energy required for discharge;
A simultaneous discharge number selection step of selecting the simultaneous discharge number of the recording elements connected to the common power supply wiring;
A correction amount calculating step of calculating an amount for correcting drive energy necessary for discharge based on a result of measuring the minimum drive energy by changing the number of simultaneous discharges in the simultaneous discharge number selection step;
A method for controlling an inspection apparatus for an ink jet head, comprising: In a control method of a recording apparatus that performs recording by a recording head in which a plurality of recording elements are arranged,
A driving energy measurement process for measuring the minimum driving energy required for discharge;
A simultaneous discharge number selection step of selecting the simultaneous discharge number of the recording elements connected to the common power supply wiring;
A correction amount calculation step of calculating a drive energy correction amount based on a result of measuring the minimum drive energy by changing the number of simultaneous discharges in the simultaneous discharge number selection step;
A control step of controlling the amount of drive energy applied to the recording element based on the correction amount;
A method for controlling an ink jet recording apparatus, comprising:

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