JP2004050467A - Image forming device - Google Patents

Abstract

(1) In an image forming apparatus having a pit-in type ink supply device, the speed of ink supply is increased. (2) Reduce the running cost of the ink. (3) It is not necessary to change ink frequently. (4) Reduce the size of the ink supply device. (5) Improve printing accuracy.
In an image forming apparatus having a pit-in type ink supply device, an ink supply amount of each color is determined from a dot count value of image data of each color ejected for recording for recording, and an ink supply amount is set between print sheets. The ink is supplied from the replenishing container to the ink tank of the carriage at a high speed by a pump.
[Selection diagram] Fig. 1

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image forming apparatus that supplies ink to an ink storage chamber of an ink tank.
[0002]
In particular, the present invention relates to an ink jet printer that performs a pit-in type ink supply in which an ink supply container and an ink tank of a carriage are not connected by a tube but are directly connected only when the ink is supplied.
[0003]
[Prior art]
In a recording head provided in this type of ink jet recording apparatus, ink is consumed at the time of image formation. Therefore, it is necessary to always supply ink to the recording head. Conventionally, the following technology has been used.
[0004]
(1) There is an ink tank in which an ink tank for generating a negative pressure with respect to a recording head is detachably mounted on a carriage. One example is a method using a head cartridge in which a recording head and an ink tank can be integrated. The easiest way to generate a negative pressure in the ink tank in this way is to use a capillary force of a porous body (ink holding body).
[0005]
(2) As a method of supplying ink to the recording head, a method is known in which an ink tank is prepared at a position different from the position where the carriage is provided, and the ink tank is connected to the recording head via a tube. In this case, ink is supplied to the recording head using a water head difference between the ink tank and the recording head or a pump.
[0006]
(3) From the viewpoint of replenishment of liquid when mounted in a device having a relatively large recording amount, such a device is provided with a large-capacity tank (hereinafter, referred to as a "large tank") for holding ink. At the same time, a head cartridge in which the ink tank and the recording head are integrally mounted is mounted on the carriage. Then, the carriage is moved to a predetermined position, and an ink tank of the head cartridge (hereinafter, referred to as a “tank part”) is connected to the large tank, so that the ink is replenished to the tank part. This is known as a so-called pit-in type ink supply system.
[0007]
[Problems to be solved by the invention]
However, the above conventional example has the following disadvantages.
[0008]
(1) In an ink cartridge in which an ink tank is removably mounted on a carriage, a large-capacity ink cartridge is directly mounted on the carriage in order to increase the amount of ink mounted on the image forming apparatus. Becomes lower. For this reason, the amount of ink mounted on the image forming apparatus cannot be increased, and it is necessary to frequently replace the ink cartridge. Therefore, the running cost of the ink increases.
[0009]
(2) In an ink jet printer that supplies ink by a method of connecting an ink tank of a carriage and an ink replenishing container with a tube, (1) the entire apparatus becomes large. (2) Since the tube is connected, the load on the carriage is reduced. , The printing accuracy is reduced.
[0010]
(3) In the pit-in type ink supply method, it took time to supply the ink.
[0011]
The purpose of the present application is as follows.
[0012]
(1) In an image forming apparatus having a pit-in type ink supply device, the speed of ink supply is increased.
[0013]
(2) Reduce the running cost of the ink.
[0014]
(3) It is not necessary to change ink frequently.
[0015]
(4) Reduce the size of the ink supply device.
[0016]
(5) Improve printing accuracy.
[0017]
(6) The error in the method of determining the ink supply amount by dot counting the image data is corrected.
[0018]
[Means for Solving the Problems]
In order to achieve the object of the above (1), according to the present invention, the ink supply amount of each color is determined from the dot count value of the image data of each color ejected for recording, and the amount of ink supply between print sheets is determined. The ink is supplied from the replenishing container to the ink tank of the carriage at a high speed by a pump.
[0019]
By performing the ink supply between print sheets of a plurality of sheets, further high-speed ink supply is realized in the pit-in type ink supply system.
[0020]
In order to achieve the above objects (2) to (5), the present invention employs a pit-in type ink supply in which the ink supply container and the ink tank of the carriage are not connected by a tube but are directly connected only at the time of ink supply. Do.
[0021]
In order to achieve the object of (6), according to the present invention, after printing, when there is no next print, the ink is supplied from the ink replenishing container to the ink tank so that the ink tank has a predetermined amount of ink. Is supplied by a pump, thereby correcting an error in the method of determining the ink supply amount by dot-counting the image data.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
[First Embodiment]
Hereinafter, an image forming apparatus according to a first embodiment of the present invention will be described with reference to FIGS.
[0023]
FIG. 2 shows a schematic configuration of an ink jet printer including the ink supply device according to the present invention.
[0024]
In FIG. 2, the inkjet printer includes a transport device 6 provided in the casing 2 along the longitudinal direction and intermittently transporting a sheet 4 as a recording medium in a direction indicated by an arrow C shown in FIG. And a carriage driving unit 10 that reciprocates the carriage member 8a with the recording unit 8 in a reciprocating manner substantially parallel to the direction in which the paper 4 is transported. .
[0025]
The transport device 6 drives the pair of roller units 12a and 12b, which are disposed to face each other substantially in parallel, a pair of roller units 14a and 14b, and the drive units that drive these roller units 12a and 12b and the roller units 14a and 14b. And a section 16. Therefore, when the drive unit 16 is activated, the sheet 4 is conveyed by intermittent feeding while being nipped by the respective roller units 12a and 12b and the roller units 14a and 14b in the direction of arrow C shown in FIG. The Rukoto.
[0026]
The carriage driving unit 10 includes a belt 20 that is wound around pulleys 18a and 18b that are disposed on rotating shafts that are arranged at predetermined intervals and a carriage member of the recording unit 8 that is disposed substantially parallel to the roller units 12a and 12b. The recording unit 8 includes a guide shaft 22 that guides the movement of the recording unit 8a, and a motor 10m that drives the belt 20 connected to the carriage member 8a in the recording unit 8 in the forward and reverse directions.
[0027]
When the motor 10m is in the operating state, when the belt 20 is rotated in the direction shown by the arrow S in FIG. 2 together with the pulley 18a connected to the motor 10m, the carriage member 8a of the recording unit 8 is moved in the same direction. Is moved by the amount of movement. When the motor 10m is activated and the belt 20 is rotated in the direction opposite to the direction indicated by the arrow S in FIG. 2, the carriage member 8a of the recording unit 8 is opposite to the direction indicated by the arrow S in FIG. Is moved in the direction by a predetermined amount of movement.
[0028]
In the recording unit 8, ink tanks 8Y, 8M, 8C, and 8B are provided for each color ink, for example, yellow, magenta, cyan, and black inks. Each of the ink tanks 8Y to 8B has an inkjet head 28. Each of the inkjet heads 28 has a plurality of ink ejection ports formed at predetermined intervals along the transport direction of the paper 4. Each ink jet head 28 has a known structure having an electrothermal converter that heats and discharges ink at its ink discharge unit.
[0029]
The ink tanks 8 </ b> Y to 8 </ b> B that supply the respective color inks to the respective inkjet heads 28 are provided detachably with respect to the carriage member 8 a of the recording unit 8. Since each of the ink tanks 8Y to 8B has the same structure as shown in FIG. 1, only the ink tank 8B will be described, and the description of the other ink tanks will be omitted.
[0030]
FIG. 4 is a block diagram of the ink jet printer according to the first embodiment of the present invention.
[0031]
The ink jet printer 300 includes a CPU 62 that controls the entire printer 300, a ROM 302 of the CPU 62, a RAM 303 of the CPU 62, an A / D converter 305 of the CPU 62, an I / F 306 for inputting print image data from the HOST PC 200, and an H- The gate array 307 for V-converting and outputting the generated print data to the print head 28 that ejects ink, and the gate array 307 is (1) a buffer when the print image data is subjected to HV conversion. 2) The DRAM 308, which is a buffer for storing print data to be output to the print head 28, the print head 28 that discharges ink by the HV converted print data, and the A / D converter 305 Individual difference data of value LICC 311, operation panel 304, main power switch 316, printer power soft switch 330, low voltage power supply 317, and auxiliary power supply 331, which are ICs that send the “rank data” and “temperature data of print head 28” to CPU 62 of printer 300. Be composed. The number of dots for ejecting ink of each color for each sheet is counted by a counter 309 in the GA 307.
[0032]
[Printing Operation of Printer 300]
When a print job is received from the HOST PC 2 via the I / F 306, the gate array 307 notifies the CPU 62 of the reception of the print job.
[0033]
The CPU 62 switches the roll paper to be used by the clutches 322 and 323 and drives the roll paper drive motor 314 to convey the roll paper. The gate array 307 performs HV conversion of the print image data received via the I / F 306, and outputs print data generated thereby to the head 28 that ejects ink. The gate array 307 uses the DRAM 308 as a buffer for performing HV conversion of print image data and as a buffer for storing print data to be output to the head 28. The CPU 62 counts the number of dots for ejecting ink of each color for each sheet with a counter 309 in the GA 307.
[0034]
The head 28 prints by ejecting ink to a medium (paper or the like) according to the print data. At this time, the LICC 311 sends, via the A / D converter 305, “rank data that is individual difference data of the resistance value of the head 28” and “temperature data of the head 28” to the CPU 62. After printing the ink, the medium (paper or the like) is discharged.
[0035]
FIG. 1 is a configuration diagram for explaining an ink supply path in the first embodiment of the ink supply device of the image forming apparatus according to the present invention. The interior of the case 30 of the ink tank 8B formed of a resin material is divided into a first room 30A for accommodating the ink absorber 32 by a partition wall 30W and a second room 30B for storing a predetermined amount of the ink IN. The first room 30A and the second room 30B are separated from each other by a communication passage 30T.
[0036]
The ink absorber 32 of the first room 30A is made of, for example, a porous material such as urethane foam. A communication hole 30a for communicating outside air with the inside of the first room 30A is provided above the first room 30A. The other end of the inkjet head 28 is connected to the first room 30A.
[0037]
Therefore, the ink contained in the ink absorber 32 is sequentially supplied to the ink ejection unit in accordance with the ink ejection operation of the inkjet head 28.
[0038]
The ink IN stored in the second chamber 30B is filled in the initial state so that a liquid level is formed in the second chamber 30B by a predetermined amount, for example, a position indicated by a two-dot chain line in FIG. . Further, septums 34A and 34B into which the tips of needles 31A and 31B of the ink supply device 26 described later are respectively pierced are provided on the wall surface facing the partition wall 30W in the second room 30B at a predetermined interval. The septums 34A and 34B are made of, for example, a rubber material, and seal the outer peripheral portions of the needles 31A and 31B when the tips of the needles 31A and 31B are pierced, respectively. The septums 34A and 34B automatically close the holes formed by the tips of the needles 31A and 31B when the tips of the needles 31A and 31B are withdrawn.
[0039]
The connection between the second chamber 30B and the tubes (needle 31A and 31B) described later is not limited to the one using the septums 34A and 34B, and the tube and the second chamber 30B are connected by a self-sealing connector. Of course. Further, at one end side of the roller units 12a and 12b, as shown in FIG. 2, a recovery unit 24 for performing a discharge recovery process of the recording unit 8 is provided at a position to be a home position of the carriage member 8a. Eight ink ejection port arrangements are provided. The recovery unit 24 includes capping members 36Y, 36M, 36C, and 36B corresponding to the respective inkjet heads 28.
[0040]
Each of the capping members 36Y to 36B is set to a position where the capping members 36Y to 36B are sealed close to the ink discharge port forming surface of each ink jet head 28 by an elevating mechanism (not shown), or at a position separated therefrom. Further, when each of the capping members 36Y to 36B is positioned close to the ink ejection port forming surface of each of the ink jet heads 28, when each of the ink jet heads 28 performs preliminary ejection of ink as an ejection recovery process, each of the ejected inks Is supplied to a waste liquid tank (not shown) through the capping members 36Y to 36B. Further, an ink supply device 26 is provided facing the recovery unit 24 with the guide shaft 22 interposed therebetween.
[0041]
As shown in FIG. 1, the ink supply devices 26 correspond to the ink tanks 8Y to 8B, respectively, and include ink supply units 38Y to 38B for storing the ink of each color to be supplied, and ink supply units 38Y to 38Y, respectively. And an injection mechanism 31 provided for each of the 38B. Since each of the ink supply units 38Y to 38B and each of the injection mechanism units 31 have the same structure, the ink supply unit 38B and the injection mechanism unit 31 provided for the ink tank 8B will be described. The description of the ink supply unit and the injection mechanism provided as described above will be omitted.
[0042]
A predetermined amount of black ink IN is stored inside the ink supply unit 38B. At an upper portion of the ink supply section 38B, an atmosphere communication port 38b for communicating the internal space with the outside air is provided. In addition, the lead-out / introduction path 42 of the ink supply unit 38B supplies the ink IN to the ink tank 8B side and supplies a predetermined amount of the ink IN stored in the second room 30B of the ink tank 8B to the ink supply unit 38B. A pump 40 for returning to the inside is provided. The pump 40 is, for example, an infusion pump and is configured to send ink by squeezing an outer peripheral portion of the tube by revolving a plurality of rollers around a rotation axis. The rotating shaft is connected to an output shaft of a driving motor. Therefore, when the output shaft of the motor is rotated in the forward or reverse direction, the plurality of rollers revolve in the forward or reverse direction while rotating. The drive of the motor is controlled based on a control signal from a CPU 62 described later.
[0043]
One end of a tube 44 made of a flexible material is connected to the inlet / outlet channel 42. The other end of the tube 44 is connected to a needle 34 </ b> B having a hole at the end communicating with the inside of the tube 44.
[0044]
The needle 34B is connected with the needle 31A by a support member 58.
[0045]
The needles 34A and 34B are supported so as to be parallel to each other and substantially perpendicular to the surfaces of the septums 34A and 34B on the rear wall surface of the ink tank 8B. The length of the needle 34B is longer by a predetermined dimension L than the length of the needle 34A. Needle 34A has a through hole at its tip that communicates with the atmosphere through its interior.
[0046]
One end of the ball screw shaft 50 of the connecting member 56 provided between the needle 34A and the needle 34B in the support member 58 is fitted to the female screw portion.
[0047]
The ball screw shaft 50 is rotatably supported by a bearing member 52 provided on the upper surface of the base 48. The other end of the ball screw shaft 50 is connected to an output shaft of the motor 46 via a joint member 54. The motor 46 is, for example, a stepping motor, and is driven and controlled based on a control signal from a CPU 62 described later.
[0048]
When the motor 46 is activated and its output shaft is rotated in the forward direction, the support member 58 is moved in the direction approaching the ink tank 8B with the needles 34A and 34B. When the output shaft is rotated in the opposite direction, the support member 58 is moved in the direction away from the ink tank 8B with the needles 34A and 34B. Therefore, when the support member 58 is moved a predetermined distance in the direction approaching the ink tank 8B with the needles 34A and 34B, the needles 34A and 34B are pierced against the surfaces of the septums 34A and 34B, respectively. It will be.
[0049]
The ink supply device 26 is further provided with a CPU 62 that controls the operation of the pump 40 and the motor 46 as shown in FIG.
[0050]
In the CPU 62, the detection signal Sp indicating that the carriage member 8a on which the ink tanks 8B to 8Y are mounted has reached a predetermined home position, and the remaining amount of ink in each of the ink tanks 8B to 8Y has become a predetermined value or less. A detection output signal group SR is supplied from the ink remaining amount detection unit 64 for detecting the fact. The remaining ink detector 64 is, for example, a liquid level sensor provided in each of the ink tanks 8B to 8Y to optically detect the remaining ink.
[0051]
The CPU 62 counts the number of dots for ejecting ink of each color for each sheet with a counter 309 in the GA 307. The CPU 62 pierces the tips of the needles 31A and 31B of the injection mechanism 31 corresponding to each of the ink tanks 8B to 8Y that require ink replenishment based on the detection signal Sp into the septums 34A and 34B, respectively, for each prescribed number of sheets. To this end, a control signal group Cmf is formed and supplied to the drive circuit unit 68. The drive circuit section 68 forms a drive control pulse signal group CMF based on the control signal group Cmf and supplies them to the motor 46. Thereby, each support member 58 is advanced by a predetermined distance toward each of the ink tanks 8B to 8Y, and the tips of the needles 31A and 31B penetrate the septums 34A and 34B, respectively, as shown in FIG. It is made to reach the inside of the second room 30B. At that time, the capping members 36 </ b> B to 36 </ b> Y are raised to cover the ink ejection port forming surface of the inkjet head 28.
[0052]
The CPU 62 forms a control signal group Chp so that each ink calculated from the number of dots of each color is supplied to each of the ink tanks 8B to 8Y, and supplies them to the drive circuit unit 66. FIGS. 3A, 3B, and 3C are diagrams that are used for describing the ink supply operation according to the first embodiment. The drive circuit section 66 forms a drive pulse control signal group CHP based on the control signal group Chp, and supplies them to each pump 40.
[0053]
As a result, a predetermined amount of ink IN is supplied to the second chamber 30B through the tube 44 and the needle 31B, and, for example, from the position near the communication path 30T to the position L shown in FIG. ₀ The liquid level will be raised up to that point. At this time, the air in the space above the ink IN in the second room 30B is discharged through the hole of the needle 31A.
[0054]
Subsequently, the control unit 62 moves the tips of the needles 31A and 31B to the positions L shown in FIG. ₀ From the position L shown in FIG. ₁ A control signal group Cmr is formed and the control signal group Cmr is supplied to the drive circuit unit 68 in order to move back. The drive circuit section 68 forms a drive control pulse signal group CMR based on the control signal group Cmr and supplies them to the motor 46. Thereby, the tip of the needle 31A is pulled out of the septum 34A.
[0055]
Subsequently, the control unit 62 returns a predetermined amount of each ink from each of the ink tanks 8B to 8Y to the ink supply units 38B to 38Y so as to set the internal pressure of the ink tanks 8B to 8Y to a predetermined negative pressure. To form a control signal group Chr and supply them to the drive circuit section 66. The drive circuit section 66 forms a drive pulse control signal group CHR based on the control signal group Chr, and supplies them to each pump 40. Thereby, for example, the liquid level of the ink IN in the second chamber 30B of the ink tank 8B is set at the position L shown in FIG. ₀ From the position L shown in FIG. ₁ The ink IN is returned to the ink supply unit 38B by a predetermined amount so as to descend by Δh. At this time, a part of the air introduced through the atmosphere communication port 30a becomes a bubble A and is taken into the second room 30B through the communication path 30T.
[0056]
Then, the control unit 62 forms a control signal group Cmr so as to further retract the tips of the needles 31A and 31B to the initial positions shown in FIG. 3C, and supplies them to the drive circuit unit 68. The drive circuit section 68 forms a drive control pulse signal group CMR based on the control signal group Cmr, and supplies them to each motor 46. As a result, the tips of the needles 31A and 31B are returned to positions separated by a predetermined distance from the ink tanks 8B to 8Y.
[0057]
As described above, the effects of the present embodiment are as follows.
[0058]
(1) The ink supply amount of each color is determined from the dot count value of the image data of each color ejected for recording, and the ink is supplied from the ink supply container to the ink tank of the carriage at high speed between print sheets. .
[0059]
By performing the ink supply between print sheets of a plurality of sheets, further high-speed ink supply is realized in an image forming apparatus having a pit-in type ink supply device.
[0060]
(2) The following is realized by performing pit-in type ink supply in which the ink supply container and the ink tank of the carriage are not connected by a tube but are directly connected only at the time of ink supply.
[0061]
{Circle around (1)} Reduce the running cost of ink.
[0062]
{Circle around (2)} Avoid replacing ink frequently.
[0063]
(3) Reduce the size of the ink supply device.
[0064]
{Circle around (4)} Improving printing accuracy.
[0065]
[Second embodiment]
Hereinafter, an image forming apparatus according to a second embodiment of the present invention will be described with reference to FIGS. 1, 2, 4, and 5. FIG.
[0066]
1, 2, and 4 are the same as those of the ink jet printer of the first embodiment. Except for the ink supply, the same operation is performed.
[0067]
FIGS. 5A, 5B, and 5C are diagrams provided for describing the ink supply operation according to the second embodiment.
[0068]
The method of determining the ink supply amount by dot counting the image data shown in the first embodiment is a very excellent and effective ink supply method because ink can be supplied at high speed. However, there is a slight difference between the ink supply amount determined by dot counting the image data and the actually used ink consumption amount. Therefore, claim 3 of the present invention for correcting this is shown in this embodiment.
[0069]
After printing, the CPU 62 forms a control signal group Chp so that a predetermined amount of each ink is supplied to each of the ink tanks 8B to 8Y when there is no next print. Supply. The drive circuit section 66 forms a drive pulse control signal group CHP based on the control signal group Chp, and supplies them to each pump 40.
[0070]
As a result, a predetermined amount of the ink IN is supplied to the second chamber 30B through the tube 44 and the needle 31B, and for example, the liquid level is raised from a position near the communication path 30T to a position shown in FIG. Become. At this time, the air in the space above the ink IN in the second room 30B is discharged through the hole of the needle 31A.
[0071]
Subsequently, the control unit 62 forms a control signal group Cmr so as to retract the tips of the needles 31A and 31B from the position shown in FIG. 5A to the position shown in FIG. These are supplied to the drive circuit unit 68. The drive circuit section 68 forms a drive control pulse signal group CMR based on the control signal group Cmr and supplies them to the motor 46. Thereby, the tip of the needle 31A is pulled out of the septum 34A.
[0072]
Subsequently, the control unit 62 returns a predetermined amount of each ink from each of the ink tanks 8B to 8Y to the ink supply units 38B to 38Y so as to set the internal pressure of the ink tanks 8B to 8Y to a predetermined negative pressure. To form a control signal group Chr and supply them to the drive circuit section 66. The drive circuit section 66 forms a drive pulse control signal group CHR based on the control signal group Chr, and supplies them to each pump 40. Thereby, for example, the ink IN in the second chamber 30B of the ink tank 8B is lowered by Δh from the position shown in FIG. 5A to the position shown in FIG. Is returned to the ink supply unit 38B by a predetermined amount. At this time, a part of the air introduced through the atmosphere communication port 30a becomes a bubble A and is taken into the second room 30B through the communication path 30T.
[0073]
Then, the control unit 62 forms a control signal group Cmr so as to further retract the tips of the needles 31A and 31B to the initial positions shown in FIG. 5C, and supplies them to the drive circuit unit 68. The drive circuit section 68 forms a drive control pulse signal group CMR based on the control signal group Cmr, and supplies them to each motor 46. As a result, the tips of the needles 31A and 31B are returned to positions separated by a predetermined distance from the ink tanks 8B to 8Y.
[0074]
As described above, the effects of the present embodiment are as follows.
[0075]
After printing, when there is no next print, the ink is supplied from the ink supply container to the ink tank by pumping the ink so that the ink tank has a predetermined amount of ink. Correct for errors in the method of determining the amount.
[0076]
【The invention's effect】
As described above, the effects of the invention according to the present application are as follows.
[0077]
(1) The ink supply amount of each color is determined from the dot count value of the image data of each color ejected for recording, and the ink is supplied from the ink supply container to the ink tank of the carriage at high speed between print sheets. .
[0078]
By performing the ink supply between print sheets of a plurality of sheets, further high-speed ink supply is realized in an image forming apparatus having a pit-in type ink supply device.
[0079]
(2) The following is realized by performing pit-in type ink supply in which the ink supply container and the ink tank of the carriage are not connected by a tube but are directly connected only at the time of ink supply.
[0080]
(5) Reduce the running cost of the ink.
[0081]
{Circle around (6)} Avoid changing ink frequently.
[0082]
{Circle around (7)} Reduce the size of the ink supply device.
[0083]
(8) Improve printing accuracy.
[0084]
(3) After printing, when there is no next print, the image data is dot-counted by supplying ink from the ink replenishing container to the ink tank by a pump so that the ink tank has a predetermined amount of ink. Error in the method for determining the ink supply amount.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing a schematic configuration of first and second embodiments of an ink supply device according to the present invention together with an ink tank.
FIG. 2 is a perspective view showing an example of an ink jet recording apparatus provided with the ink supply device according to the present invention.
FIGS. 3A, 3B, and 3C are diagrams provided for describing an ink supply operation according to the first embodiment; FIGS.
FIG. 4 is a block diagram of the ink jet printer according to the first and second embodiments.
FIGS. 5A, 5B, and 5C are diagrams provided for describing an ink supply operation according to a second embodiment; FIGS.
[Explanation of symbols]
8a Carriage member
8B, 8C, 8M, 8Y ink tank
26 Ink supply device
28 Inkjet head
28 Print head of inkjet printer
32 ink absorber
40 pump
44 tubes
62 Inkjet Printer CPU
200 HOST PC
300 inkjet printer
302 Inkjet printer ROM
303 RAM of inkjet printer
304 Operation panel of inkjet printer
305 A / D converter of CPU62 of inkjet printer
306 Printer I / F for inputting inkjet printer image data from HOST PC 200
307 Gate array of inkjet printer
308 Gate Array DRAM
311 Sends “rank data as individual difference data of the resistance value of the head 28” and “temperature data of the head 315” to the CPU 62 of the printer IC: LICC

Claims (4)

An ink tank that holds ink, a recording head that discharges ink supplied from the ink tank based on image data to perform recording on a recording medium, and a replenishing container that holds ink to be replenished in the ink tank. An image forming apparatus having
A first chamber that houses the negative pressure generating member and has a supply port and an air communication port for supplying ink to the recording head;
A second chamber having a communication part communicating with the first chamber and substantially forming a closed space except for the communication part,
The second chamber and the replenishing container have a first path for communicating the gas in the second chamber with the gas in the replenishing container, and a first path for moving the ink in the replenishing container to the second chamber. While conducting by a second path different from the first path,
A pump capable of promoting the movement of ink from the replenishing container to the second chamber and from the second chamber to the replenishing container,
Means for counting the number of dots of image data for ejecting ink to the recording medium, from recording on the recording medium until recording on the next recording medium, from the number of dots; An image forming apparatus, wherein a determined supply amount of ink is supplied from the replenishing container to the ink tank. For each of a plurality of recording media, the image data for ejecting ink is counted, and after the recording is performed on the plurality of recording media, the recording is performed on the next plurality of recording media. 2. The image forming apparatus according to claim 1, wherein a supply amount of ink determined from the number of dots is supplied from the replenishing container to the ink tank. After recording on a recording medium, when there is no recording on the next recording medium, supplying ink from the replenishing container to the ink tank so that the ink tank has a predetermined amount of ink. The image forming apparatus according to claim 1, wherein: The image forming apparatus further includes a carriage capable of mounting the ink tank, a scanning unit configured to relatively move the carriage along a recording surface of the recording medium, and a transport unit configured to transport the recording medium. The image forming apparatus according to claim 1, wherein:

Images