JP2013248860A - Inkjet recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent unnecessary replacement of a recording head because there is a possibility that recording heads are replaced even in an abnormal temperature increase caused by bubbles that can be removed by ink filling operation or recovery operation if recording heads are replaced whenever determination of the abnormal temperature increase is made without a cause for the abnormal temperature increase being specified.SOLUTION: When temperature of a recording element substrate is a threshold temperature or more determined to be an abnormal one, and an amount about an ejection port which is non-ejection is a predetermined one or less, unnecessary replacement of recording heads can be prevented by instructing a user to replace the recording heads.

Description

  The present invention relates to an ink jet recording apparatus.

  In a thermal inkjet recording apparatus, an image is formed by ejecting ink from a recording element substrate having an ejection port array composed of a plurality of ejection ports for ejecting ink. Specifically, film boiling occurs due to thermal energy generated by a heating resistor element (hereinafter also referred to as a heater) provided so as to correspond to the ejection port, and ink is ejected from the ejection port by the pressure of bubbles generated at this time. Then, an image is formed by landing on the recording medium.

  When a recording operation is performed for a long time using such a heater, heat is stored in the recording element substrate, and the temperature of the recording element substrate rises. If the ambient temperature of the heater becomes high, the viscosity of the ink may decrease, and the ink droplet ejection direction may be disturbed or ejection may not be possible. Then, it is known to suppress the recording for a certain time. Patent Document 1 discloses an ink jet recording apparatus that performs temperature rise suppression control by providing a temperature sensor on each recording element substrate in a recording head having a recording element substrate to detect the temperature of each chip.

  Further, when the temperature detected by such a temperature sensor is an abnormal temperature higher than expected, a failure or breakage of a circuit, wiring or the like occurs as disclosed in Patent Document 2. It is known to replace the recording head by judging that there is a possibility.

JP 2006-43923 A JP 2000-94653 A

  In order to increase the recording speed in the ink jet recording apparatus, for example, a full-line long recording head capable of completing an image by one recording scan can be used. Since such a full-line long head is relatively expensive, it is preferable in terms of cost to replace the recording head at a high frequency by judging only the temperature abnormality as disclosed in Patent Document 2. Absent. Therefore, determine whether the abnormal temperature rise of the printhead substrate is due to recoverable or unrecoverable causes, and replace the printhead only when it cannot be recovered. Is required.

  The present invention has been made in view of such a problem, and can determine the cause of the temperature rise of the recording element substrate, and can perform highly reliable ink jet recording that can instruct the user to replace the recording head at an appropriate timing. The object is to provide a device.

  Therefore, an ink jet recording apparatus according to the present invention includes a recording head including a recording element substrate having an ejection port array composed of a plurality of ejection ports, a temperature sensor that detects a substrate temperature of the recording element substrate, and a non-ejection among the ejection port arrays. Inspection means for determining the number of discharge failure outlets that are discharged, and the substrate temperature detected by the temperature sensor is equal to or higher than a threshold temperature at which the temperature of the recording element substrate is determined to be an abnormal temperature, and It has a control part which gives an instruction to a user to replace the recording head when the number of ejection failure outlets is less than a predetermined number.

  According to the present invention, since it is possible to determine whether or not the cause of the temperature rise of the recording element substrate can be recovered, a highly reliable ink jet recording apparatus that can issue a recording head replacement instruction at an accurate timing Can be provided.

1 is a perspective view schematically showing a recording apparatus according to the present invention. 1 is a perspective view of a recording head according to the present invention. FIG. 2 is an exploded perspective view of a recording head according to the present invention. FIG. 3 is an exploded perspective view of a recording element unit according to the present invention. 1A and 1B are a perspective view and a cross-sectional view of a recording element substrate according to the present invention. It is a figure explaining the position of a temperature sensor. It is a figure explaining the temperature detection method by a temperature sensor. FIG. 6 is a diagram illustrating a state in which bubbles are mixed in a recording element substrate. It is a figure explaining the detection temperature when a bubble mixes. It is a figure explaining undischarge detection operation. It is a flowchart explaining the control which isolates the cause of abnormal temperature rise.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the following description, a recording apparatus using an ink jet recording method will be described as an example. The recording apparatus may be, for example, a single function printer having only a recording function, or may be, for example, a multi-function printer having a plurality of functions such as a recording function, a FAX function, and a scanner function. In addition, for example, a manufacturing apparatus for manufacturing a color filter, an electronic device, an optical device, a minute structure, and the like by a predetermined recording method may be used.

  In the following description, “recording” is not limited to the case where significant information such as characters and figures is formed, and it does not matter whether it is significant. Further, it also represents a case where an image, a pattern, a pattern, a structure, or the like is widely formed on a recording medium or a medium is processed regardless of whether or not it is manifested so that a human can perceive it visually.

  “Recording medium” represents not only paper used in general recording apparatuses but also cloth, plastic film, metal plate, glass, ceramics, resin, wood, leather, and the like that can accept ink. .

  Further, “ink” should be interpreted widely as in the definition of “recording”. Therefore, by being applied on the recording medium, it can be used for forming an image, pattern, pattern, etc., processing the recording medium, or processing the ink (for example, coagulation or insolubilization of the colorant in the ink applied to the recording medium). Represents a liquid that can be provided.

  FIG. 1 is a diagram showing an example of the configuration of an ink jet recording apparatus (hereinafter referred to as a recording apparatus) 1 according to an embodiment of the present invention.

  The recording apparatus 1 is provided with a so-called full line type recording head 2 having a recording width corresponding to the width of the recording medium. A plurality of recording heads 2 are provided corresponding to each color (2Y, 2M, 2C, 2Bk). Specifically, a recording head 2Y that discharges yellow ink, a recording head 2M that discharges magenta ink, a recording head 2C that discharges cyan ink, and a recording head 2Bk that discharges black ink are provided. As shown in FIG. 2, each of these recording heads is provided so as to extend in a direction (nozzle arrangement direction: Y direction) orthogonal to the conveyance direction (scanning direction: X direction) of the recording medium P.

  Each recording head 2 is connected to four ink tanks 3Y, 3M, 3C, and 3Bk (hereinafter collectively referred to as ink tanks 3) that store yellow ink, magenta ink, cyan ink, and black ink, respectively. 4 is connected. Each ink tank 3 can be attached and detached independently.

  The recording head 2 is provided at a position facing the platen 6 with the conveying belt 5 interposed therebetween. The recording head 2 is moved up and down in the direction facing the platen 6 by the head moving unit 10. The operation of the head moving unit 10 is controlled by the control unit 9.

  The recording head 2 is provided with a plurality of recording element substrates H1100 each having an ejection port array composed of a plurality of ejection ports for ejecting ink. Such an ejection port is provided with a recording element that generates energy for ejecting ink. Specifically, an ink jet method is employed in which ink is ejected using thermal energy, and a heating resistor element (hereinafter also referred to as a heater) is provided to generate thermal energy.

  Here, the heater is electrically connected to the control unit 9 via the head driver 2a, and the heater is driven and stopped in accordance with an on / off signal (discharge / non-discharge signal) sent from the control unit 9. Is controlled.

  The control unit 9 performs overall control of various processes in the recording apparatus 1. The control unit 9 includes, for example, a CPU (Central Processing Unit), a memory such as a ROM and a RAM, an ASIC (Application Specific Integrated Circuit), and the like.

  On the side of the recording head 2, a preliminary discharge operation and a suction recovery operation performed to maintain and recover the discharge port state of the recording head 2 are performed. The cap 7 is arranged in a state. The operation of the cap moving unit 8 is controlled by the control unit 9 and controls the cap 7 to move the cap 7 directly below the recording head 2 so that the waste ink discharged from the ink discharge port is received by the cap 7. Further, by performing the suction operation in a state where the recording head 2 is covered with the cap 7, ink can be filled in the flow path of the recording element substrate.

  The transport belt 5 plays a role of transporting the recording medium P and is stretched around a driving roller connected to the belt driving motor 11. The operation of the conveyor belt 5 is switched by the motor driver 12.

  A charger 13 is provided on the upstream side of the conveying belt 5. The charger 13 charges the conveyance belt 5 to bring the recording medium P into close contact with the conveyance belt 5. The charger 13 is turned on / off by a charger driver 13a. The pair of feeding rollers 14 supplies the recording medium P onto the conveying belt 5. The feeding motor 15 drives and rotates the pair of feeding rollers 14. The operation of the feeding motor 15 is controlled by a motor driver 16.

  The inspection unit 26 is a unit that optically reads an inspection pattern or image recorded on a recording medium by the recording head 2 and inspects a nozzle state, a sheet conveyance state, an image position, and the like of the recording head. Specifically, the inspection unit 26 is a CCD line sensor, and the sensors are arranged in a direction perpendicular to the sheet conveyance direction. The control unit 9 performs image analysis on the image read by the inspection unit 26 as described above, so that the discharge port (undischarge discharge port) in the undischarge state can be specified.

  The above is the description of an example of the configuration of the recording apparatus 1. Note that the configuration of the recording apparatus 1 illustrated in FIG. 1 is merely an example, and is not necessarily limited to such a configuration. For example, in the configuration of FIG. 1, the recording medium P is transported with respect to the recording head 2, but any configuration in which the recording head 2 and the recording medium P move relative to each other may be used. It doesn't matter. For example, the recording head 2 may move with respect to the recording medium P.

  Next, an example of the configuration of the recording head 2 shown in FIG. 1 will be described with reference to FIGS.

  FIG. 2 is a perspective view of the recording head 2 as viewed from the side where the discharge ports are provided. In FIG. 2, four recording element substrates H1100a, H1100b, H1100c, and H1100d are arranged in a staggered pattern so that a wide area can be recorded at once. Here, the case where the number of the recording element substrates H1100 is four is shown, but by increasing the number, it is possible to provide a recording head according to the recording width. In addition, an area (L) overlapping in the Y direction is provided at the end of each recording element substrate H1100, thereby preventing a gap from being generated in recording by each recording element substrate H1100.

  FIG. 3 is a schematic diagram showing the recording head 2 disassembled into a recording element unit H1001 and an ink supply member H1500. The recording element unit H1001 is provided with a plurality of the recording element substrates H1100 described above. The ink supply member H1500 is formed by resin molding, for example, and includes a common liquid chamber H1501.

  FIG. 4 is an exploded schematic view of the recording element unit H1001. The recording element unit H1001 includes a plurality of recording element substrates H1100, a first plate H1200, an electric wiring substrate H1300, a second plate H1400, and a filter member H1600.

  The electrical wiring board H1300 is used to send an electrical signal or the like for ejecting ink to the recording element board H1100. An opening for incorporating the recording element substrate H1100 is formed in the electric wiring substrate H1300. The second plate H1400 is bonded and fixed to the back surface of the electrical wiring board H1300.

  The electrical wiring board H1300 is provided with an electrode terminal H1302 corresponding to an electrode (H1103 shown in FIG. 5A) of the recording element substrate H1100 and an external signal input terminal H1301 for receiving an electrical signal from the recording apparatus main body. .

  The electrical wiring substrate H1300 is electrically connected to the recording element substrate H1100. More specifically, the electrode (H1103 shown in FIG. 5A) of the recording element substrate H1100 and the electrode terminal H1302 of the electric wiring substrate H1300 are electrically connected by a wire bonding technique. As a material of the electric wiring board H1300, for example, a flexible wiring board having a two-layer structure is used, and the surface layer is covered with a polyimide film.

  The first plate H1200 is made of alumina having a thickness of 0.5 to 10 mm, for example. Note that the material of the first plate H1200 is not limited to alumina. For example, the first plate H1200 has a linear expansion coefficient equivalent to the linear expansion coefficient of the material of the recording element substrate H1100, and has a thermal conductivity equivalent to or exceeding the thermal conductivity of the material of the recording element substrate H1100. It may be made of materials. More specifically, the material of the first plate H1200 is, for example, silicon (Si), aluminum nitride (AlN), zirconia, silicon nitride (Si3N4), silicon carbide (SiC), molybdenum (Mo), tungsten (W ).

  In the first plate H1200, an ink supply portion H1201 for supplying ink to the recording element substrate H1100 is formed. The ink supply port (H1101 shown in FIG. 5B) of the recording element substrate H1100 corresponds to the ink supply unit H1201 of the first plate H1200.

  The second plate H1400 is formed of a plate having a thickness of 0.5 to 1 mm, for example. Specifically, a SUS material or the like can be used. Further, it may be made of a material having ink resistance and good flatness. The second plate H1400 has a recording element substrate H1100 bonded and fixed to the first plate H1200 and an opening for taking in the recording element substrate H1100, and is bonded and fixed to the first plate H1200.

  A sealant is filled between the opening of the second plate H1400 and the groove formed by the side surface of the recording element substrate H1100, and the electrical mounting portion of the electrical wiring substrate H1300 is sealed. Further, the electrodes (H1103 shown in FIG. 5A) of the recording element substrate H1100 are also sealed with a sealing agent, and the electrical connection portion is protected from ink corrosion and external impact.

  A filter member H1600 for removing foreign matter mixed in the ink is bonded and fixed to the back surface side ink supply port H1201 of the first plate H1200.

  Next, an example of the configuration of the recording element substrate H1100 will be described with reference to FIGS. 5 (a) and 5 (b). FIG. 5A is an example of an external configuration of the recording element substrate H1100, and FIG. 5B is a cut surface when the recording element substrate H1100 is cut along AA ′ in FIG. This state is schematically shown.

  The recording element substrate H1100 is formed of a silicon substrate H1108 provided with a plurality of heating resistance elements H1102, and a flow path member H1110 that forms a plurality of discharge ports H1105 and a flow path H1107. In addition, the recording element substrate H1100 is bonded so that the discharge port H1105 of the flow path member H1110 and the heating resistor element H1102 on the silicon substrate H1108 face each other.

  In the silicon substrate H1108, an ink supply port H1101 including a long groove-like through-hole for supplying ink discharged from the discharge port H1105 is formed. In addition, an electrode H1103 for receiving electric power or an electric signal from the outside is provided.

  That is, the ink supplied from the ink tank 3 is carried to the flow path H1107 via the connection pipe 4, the common liquid chamber H1501, the ink supply part H1201, and the ink supply port H1101. Then, by applying a voltage to the corresponding heating resistor element according to the recording signal, the ink in the flow channel boils and vaporizes due to the heat generated by the heating resistor element H1102, and the pressure generated at this time causes the ink to be ejected from the ejection port. A recording operation is performed by discharging from H1105.

(Regarding temperature sensor)
Each of the recording element substrates H1100 is provided with a temperature sensor as shown in FIG. In FIG. 6, four temperature sensors H1120a, H1120b, H1120c, and H1120d are provided on four recording element substrates H1100a, H1100b, H1100c, and H1100d, respectively.

  FIG. 7 is a diagram for explaining a temperature detection method.

  The output of the temperature sensor H1120 provided in the recording element substrate H1100 is sent to the control unit 9, and the temperature of each recording element substrate H1100 can be detected. Specifically, the output of the temperature sensor H1120 is extracted by the wiring 25 (25a to 25d) and input to the multiplexer 23. The multiplexer 23 selects the output of one of the temperature sensors H1120. The output of the selected temperature sensor H1120 is output via a terminal H1301 provided for electrically connecting the recording head 2 and the recording apparatus.

  By enabling the substrate temperature of each recording element substrate H1100 to be detected by such a temperature sensor, the recording apparatus 1 can determine the driving condition of the heater in order to control the discharge amount.

  Also, if the output result of the temperature sensor exceeds the specified value and an abnormal temperature of the printing element substrate is detected, printing is temporarily stopped with the applied voltage turned off to guarantee the safety of the device and the image quality. And protect control that notifies users of errors.

  Such an abnormal temperature is higher than a temperature that does not reach as long as the substrate and circuit of the printhead / printer body operate normally and the temperature of the ink flowing into the printhead is controlled to perform normal printing. It is set to be. It is set so that the temperature is surely below the temperature at which other circuits and members are not damaged or failed due to the abnormal temperature of the recording head. Specifically, 70 ° C. is set as a threshold value, and it is determined that the temperature is abnormal when the print head temperature is 70 ° C. or higher (threshold temperature or higher). The reason why such an abnormal temperature rise occurs can be (1) caused by bubbles and (2) caused by defective wiring of the recording element substrate.

  First, the situation where the temperature rises due to bubbles will be described.

  Ink is supplied from the ink tank to the liquid chamber of the recording element substrate through the ink supply path of the connection pipe 4, the common liquid chamber H1501, the ink supply unit H1201, and the ink supply port H1101, and at this time, bubbles are also supplied. It can be considered. If bubbles are mixed into the liquid chamber, the heat of the heater cannot be transmitted to the ink, and the ink cannot be ejected. That is, since the heater is empty, the heat of the heater is not used for foaming and is not released to the outside together with the ejected ink. That is, in the case of non-ejection due to bubbles, the temperature of the recording element substrate rises because heat storage proceeds as compared with the case where ink can be ejected normally.

  In this embodiment, the case where non-ejection occurs due to air bubbles has been described. However, the present invention is not limited thereto, and the same applies to the case where non-ejection occurs due to the clogging of the ejection port due to the influence of the environment or the like.

  FIG. 8 schematically shows the state of the cut surface when the recording element substrate H1100 is cut along B-B ′ of FIG.

  FIG. 8A shows a state A in which the flow path H1107 and the supply port H1101 are sufficiently filled with ink. FIG. 8B shows a state B in which there are bubbles 60 in a part of the flow path H1107 and about 1/3 of the ejection port array is non-ejection. FIG. 8C shows a state C in which the flow path H1107 and the supply port H1101 are not filled with ink.

  FIG. 9 is a graph showing a change in temperature output detected by the temperature sensor when the recording element substrate H1100 in the state shown in FIG. 8 is driven for a predetermined time. At this time, an experiment was performed using ink having a temperature of 25 ° C. From here, the temperature of the head is about 60 ° C. in the state A, whereas the temperature of the head is increased to 70 ° C. or more in the state B, and 90 ° C. or more in the state C. It can be seen that the temperature has increased to.

  When the abnormality determination threshold is 70 ° C., the temperatures detected in the state B and the state C are abnormal temperatures, and it is determined that an abnormal state has occurred. However, when such bubbles are present, the recording head itself has not failed, so if the ink filling operation or recovery operation is performed into the liquid chamber to discharge the bubbles in the liquid chamber, the recording head It can be said that it can be used.

  Next, a situation in which a temperature rise due to a wiring defect of the recording element substrate will be described.

  The recording element substrate is provided with a driving circuit such as a logic circuit used for transmitting and receiving logic signals such as a clock signal and a print data signal and wiring for supplying a voltage in order to drive the recording element. Yes. In such a circuit, current leakage occurs due to, for example, the microphone used in the wiring, and the place where the current leakage occurs may generate heat. When the recording operation is performed in such a situation, the temperature of the recording element substrate rises abnormally even in the state A in which the flow path H1107 and the supply port H1101 are sufficiently filled with ink, and the recording head fails. This may lead to failure or damage to other circuits and components. Therefore, it can be said that it is necessary to notify the user of the printing stop and the replacement of the recording head from the viewpoint of maintaining the recording apparatus and maintaining the safety for the user. Note that a full-line type ink jet recording apparatus that performs a recording operation at a higher printing speed uses a larger current than an ordinary household ink jet recording apparatus that performs recording at about A4. It can be said that poor wiring is likely to occur. It should be noted that such a temperature rise due to the wiring defect of the recording element substrate cannot be recovered even if the ink filling operation or the recovery operation is performed, and thus it can be said that the recording head must be replaced.

  Conventionally, the cause of the two abnormal temperature rises as described above has not been separated, so that the recording head may be replaced even in the case of an abnormal temperature rise caused by recoverable bubbles. Necessary recording head replacement occurred.

  The present invention combines the detection of abnormal temperature and the undischarge detection operation for detecting the ink discharge state, so that recovery is possible due to abnormal recoverable temperature rise caused by bubbles and the like, and wiring failure of the printing element substrate. It is separated from abnormal temperature rise.

(Undischarge detection operation)
FIG. 10A is a schematic diagram showing the positional relationship between the recording head 2, the inspection unit 26, the image 201 on the recording medium P, and the inspection pattern 200 for performing the discharge failure detection operation. The recording medium P is conveyed from the left direction (upstream side) to the right direction (downstream side) in FIG. 10, and the image 201 and the inspection pattern 200 are recorded by the recording head 2 during that time. The inspection pattern 200 can be recorded at an arbitrary interval between images.

  FIG. 10B shows the relationship between the ejection openings of one recording element substrate H1100 and the inspection pattern for detecting undischarge recorded on the recording medium. Here, an example is shown in which four ejection port arrays are provided on the recording element substrate H1100. The discharge ports are counted as 0 Seg and 1 Seg from the left side of the drawing.

  As shown in FIG. 10B, when the recording element substrate H1100 has a plurality of ejection port arrays A to D, the inspection pattern is recorded separately for each ejection port array. In addition, the accuracy of ejection determination can be improved by using an inspection pattern that is ejected in order from adjacent ejection ports in the direction intersecting with the conveyance direction of the recording medium in each region.

  By reading such an inspection pattern with the inspection unit 26 and analyzing the image with the control unit 9, it is possible to specify the ejection port in the non-discharge state. Specifically, the inspection unit 26 detects a low luminance value at a position where ejection is normally performed, and detects a higher luminance value than a normal position at a position where ejection is not performed. That is, by specifying a position where the value of the luminance difference ΔP of the inspection pattern is large, it is possible to count the positions of the ejection ports that are not ejecting and the number of ejection ports that are not ejecting.

(Separation sequence of temperature rise due to air bubbles and abnormal temperature rise due to wiring failure)
FIG. 11 is a flowchart showing a separation sequence of a temperature rise due to bubbles and an abnormal temperature rise due to wiring failure. This control is periodically performed during the printing operation.

  First, at a predetermined timing during printing, it is detected by the temperature sensor of the recording element substrate whether the detected temperature of each recording element substrate is equal to or higher than the threshold value of 70 ° C. (S1). If the detected temperature is less than 70.0 ° C., it is determined that the temperature is normal and the printing operation is continued.

  If the detected temperature is 70 ° C. or higher in S1, it is determined that the temperature is abnormal, the recording operation is stopped, and the voltage applied to the recording head is turned off (S2).

  Next, the discharge failure detection operation is performed using the inspection pattern printed immediately before the stop of printing. Specifically, the inspection pattern is read by the inspection unit 26, and the number N of ejection ports that are not ejected is obtained (S3). Then, it is determined whether or not the number N of ejection ports that are not ejecting is less than 1/3 of the total number of ejection ports of one ejection port array (S4).

  When the number of ejection ports that are not ejecting is less than a predetermined number, specifically, less than 1/3 of the total number of ejection ports, the temperature of the recording element substrate is abnormal despite the presence of ink near the heater. It can be said that it is temperature. Therefore, it is determined that there is a high possibility that a printhead wiring failure or the like has occurred, and a printhead replacement notification is made (S5).

  On the other hand, when the number of ejection ports that are not ejecting is a predetermined number or more, specifically, 1/3 or more of the total number of ejection ports, there is a high possibility that an ejection failure due to air bubbles has occurred. The ink filling / recovery operation sequence is performed (S6). Then, the voltage applied to the recording element substrate is turned ON (S7), and it is detected again by the temperature sensor of the recording element substrate whether the detected temperature of each recording element substrate is equal to or higher than the threshold value of 70.0 ° C. (S8). ). At this time, when the detected temperature is lower than 70.0 ° C., the normal standby state is restored (S10).

  If the detected temperature is 70.0 ° C. or higher in S8 even though the ink filling / recovery operation sequence is performed, it can be said that the discharge is not caused by bubbles. In this case, it can be said that there is a high possibility that a printing element substrate wiring failure has occurred so that the ink ejection operation cannot be continued. Therefore, the voltage applied to the recording element substrate is turned OFF (S9), Exchange notification is performed (S5).

  By making the determination as described above, it is possible to distinguish between an abnormal temperature rise caused by recoverable bubbles and an abnormal temperature rise due to wiring failure of the recording element substrate that cannot be recovered. As a result, in the case of an abnormal temperature rise due to recoverable bubbles, replacement of the recording head is not instructed, and unnecessary recording head replacement does not occur. That is, it is possible to provide a highly reliable ink jet recording apparatus that can issue a recording head replacement instruction at an appropriate timing.

  In S3, the ratio of the non-ejection outlets of all the ejection outlets in the ejection orifice array may be obtained without determining the number of ejection outlets in the ejection outlet row in detail. In this case, when the detected temperature of the recording element substrate is equal to or higher than the threshold value and the non-ejection ratio is less than the predetermined amount, it is determined that the temperature cannot be recovered, and the user is instructed to replace the recording head. Can be controlled. Even when the detected temperature of the printing element substrate is equal to or higher than the threshold value, the recovery operation can be performed by determining that the temperature can be recovered when the non-ejection ratio is equal to or higher than a predetermined amount. In the sequence shown in FIG. 11, the predetermined number is described as 1/3 of all the ejection ports included in the ejection port array, but these predetermined numbers are appropriately set in consideration of the thermal conductivity of the recording element substrate. Is possible.

DESCRIPTION OF SYMBOLS 1 Recording device 2 Recording head 26 Inspection part H1100 Recording element board | substrate H1105 Discharge port H1120 Temperature sensor

Claims (10)

A recording head including a recording element substrate having an ejection port array composed of a plurality of ejection ports;
A temperature sensor for detecting a substrate temperature of the recording element substrate;
An inspection means for obtaining an amount related to a discharge failure discharge port that has failed discharge in the discharge port row;
When the substrate temperature detected by the temperature sensor is equal to or higher than a threshold temperature at which the temperature of the recording element substrate is determined to be an abnormal temperature, and the amount related to the discharge failure outlet is less than a predetermined amount, the recording An ink jet recording apparatus, comprising: a control unit that instructs a user to replace a head. A recovery means for recovering the ejection state of the recording head;
The inkjet recording apparatus according to claim 1, wherein the control unit performs control so that a recovery operation by the recovery unit is performed when an amount related to the discharge failure discharge port is equal to or greater than the predetermined amount.   3. The control unit according to claim 2, wherein when the substrate temperature detected after performing the recovery operation is equal to or higher than the threshold temperature, the control unit issues an instruction to the user to replace the recording head. Inkjet recording apparatus.   The said test | inspection means calculates | requires the quantity regarding the said discharge failure discharge port by test | inspecting the test | inspection pattern recorded on the recording medium with the said recording head. Inkjet recording apparatus.   The inkjet recording apparatus according to claim 1, wherein the recording element substrate has a supply port that supplies ink to a plurality of ejection ports.   The inkjet recording apparatus according to claim 1, wherein the temperature sensor is provided on the recording element substrate.   The ink jet recording apparatus according to claim 1, wherein the recording head is a full-line type recording head.   2. The recording element substrate according to claim 1, wherein a plurality of heating resistance elements that generate thermal energy for ejecting ink are provided so as to correspond to the plurality of ejection openings, respectively. 8. The ink jet recording apparatus according to any one of 7 above.   The inkjet recording apparatus according to claim 1, wherein the amount related to the discharge failure outlet is the number of discharge failure discharge ports.   The ink jet recording apparatus according to claim 1, wherein the amount related to the discharge failure outlet is a ratio of discharge failure outlets to all discharge ports.

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