JP6870221B2 - Inkjet recording device and abnormality detection method for inkjet recording device - Google Patents

Description

The present invention relates to an inkjet recording device and a method for detecting an abnormality in an inkjet recording device.

Conventionally, there is an inkjet recording device that ejects ink from a nozzle and records an image or the like on a recording medium. In recent years, the speed and accuracy of images recorded by inkjet recording devices have been further increased in accordance with the miniaturization of nozzles and the increase in the number of nozzles.

The ink flow path in which a large number of parts are combined to distribute liquid ink has a problem that leakage may occur in the ink flow path due to defects in these parts or improper installation. On the other hand, there is a technique of detecting the presence or absence of ink leakage in the ink flow path by measuring the pressure in the ink flow path with a predetermined ink (fluid) flowing through the flow path. Patent Document 1).

Japanese Unexamined Patent Publication No. 2009-23379

However, once the ink leaks, there is a problem that labor and cost increase not only for the parts related to the leak but also for cleaning the dirt with the leaked ink and replacing the parts due to a short circuit of the circuit with the ink. is there.

An object of the present invention is to provide an inkjet recording device and a method for detecting an abnormality in an inkjet recording device, which can detect a sealing defect related to an ink flow path configuration more easily and easily.

In order to achieve the above object, the invention according to claim 1 has a path for supplying ink to the nozzle and a gas in the path different from the pressure outside the path without introducing ink into the path. A sealing defect detecting means for detecting a sealing defect in the path based on the pressure of the gas when the pressure is set to 1 and a gas in the path are subjected to the gas in the path by the pressure applying means without introducing ink into the path. A sealing defect detecting means for detecting a sealing defect in the path based on the measurement result of the gas pressure by the pressure measuring means when the first pressure is different from the pressure outside the path is provided. The pressure applying means is an inkjet recording apparatus including a liquid feeding means for feeding ink in an ink flow path through which ink flows in the path.

The invention according to claim 2 is the inkjet recording apparatus according to claim 1.
An opening / closing means that partially seals the path in predetermined ranges,
An opening / closing control means that controls the opening / closing operation of the opening / closing means,
With
The sealing defect detection means, said sealing failure at each within the predetermined range is characterized in a detecting child. Further, the invention according to claim 3 is the inkjet recording apparatus according to claim 1 or 2 , wherein the sealing defect detecting means changes the pressure after the gas in the path is set to the first pressure. It is characterized in that the sealing defect is detected based on the above.

The invention according to claim 4 is the inkjet recording apparatus according to any one of claims 1 to 3.
It is characterized by including a heating means for heating at least a part of the ink flow path through which ink flows in the above-mentioned path.

The invention according to claim 5 is the inkjet recording apparatus according to any one of claims 1 to 4.
The path includes an ink flow path through which ink flows and a gas flow path for adjusting the flow of ink in the ink flow path.

The invention according to claim 6 is the inkjet recording apparatus according to claim 5.
The pressure applying means is characterized in that it includes a means for adjusting the pressure of a gas in the gas flow path.

The invention according to claim 7 is the inkjet recording apparatus according to any one of claims 1 to 6.
The sealing defect detecting means measures the pressure when the ink in the path is set to a second pressure different from the first pressure by the pressure applying means in a state where the ink is introduced into the path. It is characterized in that a sealing defect in the path is detected based on the measurement result relating to the pressure of the ink by the means.

The invention according to claim 8 is the inkjet recording apparatus according to claim 7.
The sealing defect detecting means seals the seal based on different criteria depending on whether the gas in the path is the first pressure or the ink in the path is the second pressure. It is characterized by determining the presence or absence of defects.

The invention according to claim 9 is the inkjet recording apparatus according to claim 7 or 8.
A heating means for heating at least a part of the ink flow path through which ink flows in the above-mentioned path,
A heating control means that controls the operation of the heating means,
With
The heating control means is characterized in that the heating means is not operated when the sealing defect detecting means detects a sealing defect in a state where ink is not introduced into the path.

The invention according to claim 10 is the inkjet recording apparatus according to any one of claims 1 to 9.
It is characterized by including a display means for displaying the detection result by the sealing defect detecting means.

請Motomeko 11 the described invention, a path for supplying ink to the nozzle, a pressure applying means for applying a pressure to the fluid in said path, and a pressure measuring means for performing measurements according to the pressure in said path, A method for detecting an abnormality of an inkjet recording apparatus comprising the above, wherein the gas in the path is set to a first pressure different from the pressure outside the path by the pressure applying means in a state where ink is not introduced into the path. The pressure applying means includes an ink flow path through which ink flows in the pressure applying means, which includes a sealing defect detection step of detecting a sealing defect in the path based on a measurement result relating to a gas pressure by the pressure measuring means. It is characterized in that a liquid feeding means for feeding the ink is included in the above.

According to the present invention, there is an effect that the inkjet recording apparatus can detect a sealing defect related to the ink flow path configuration more easily and easily.

It is a schematic diagram which shows the structure of the inkjet recording apparatus of embodiment of this invention. It is a bottom view which shows the nozzle surface of a head unit. It is a figure explaining the structure which concerns on the ink flow path in the inkjet recording apparatus of this embodiment. It is a block diagram which shows the functional structure of the inkjet recording apparatus of this embodiment. It is a figure which shows the example of the time change of the air pressure measured by a sensor at the time of a leak inspection. It is a flowchart which shows the control procedure of the flow path leakage detection processing executed by the inkjet recording apparatus of this embodiment. It is a flowchart which shows the control procedure of the flow path leakage detection processing executed by the inkjet recording apparatus of this embodiment. It is a flowchart which shows the control procedure of the flow path monitoring process executed by an inkjet recording apparatus.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic view showing the configuration of the inkjet recording apparatus 100 according to the embodiment of the present invention.
FIG. 1 shows a case where the inkjet recording device 100 is viewed from the front.

The inkjet recording apparatus 100 has a line head, and is a one-pass method for forming a color image by ejecting inks of a plurality of colors, here, four colors at appropriate timings while moving a recording medium with respect to the line head. Printer.
The inkjet recording device 100 includes a medium supply unit 10, an image forming main body unit 20, a medium ejection unit 30, an ink supply unit 50 (see FIG. 3), a control unit 40 (see FIG. 4), and the like. In the inkjet recording device 100, based on the control by the control unit 40, the recording medium P stored in the medium supply unit 10 is conveyed to the image forming main body unit 20, and after the image is formed, it is discharged to the medium discharging unit 30. To.

The medium supply unit 10 sends the recording media P stored inside to the image forming main body 20 one by one.
As the recording medium P, in addition to printing paper having various thicknesses, various media such as cells, films, and cloths that can be curvedly supported on the outer peripheral surface of the image forming drum 22 are used.

The medium supply unit 10 has a supply tray 11 for storing the recording medium P, and a feeder board 12 for transporting the recording medium P from the supply tray 11 to the image forming main body 20. The supply tray 11 is a plate-shaped member provided on which one or a plurality of recording media P can be placed. The supply tray 11 is provided so as to move up and down according to the amount of the recording medium P placed on the supply tray 11, and the position where the highest recording medium P is conveyed by the feeder board 12 in the vertical movement direction. Is held at.
The feeder board 12 is mounted on a transport mechanism that drives a ring-shaped belt 123 supported by a plurality of (for example, two) rollers 121 and 122 on the inside to transport the recording medium P on the belt 123, or on a supply tray 11. It has a supply unit that delivers the highest mounted recording medium P onto the belt 123. The feeder board 12 conveys the recording medium P delivered on the belt 123 by the supply unit along the belt 123.

The image forming main body 20 includes a delivery unit 21, an image forming drum 22, a head unit 23, an irradiation unit 24, a delivery unit 25, and the like.

The delivery unit 21 delivers the recording medium P delivered from the medium supply unit 10 to the image forming drum 22. The transfer unit 21 has a swing arm portion 211 that supports one end of the recording medium P conveyed by the feeder board 12, and a cylindrical transfer drum that transfers the recording medium P supported on the swing arm portion 211 to the image forming drum 22. The recording medium P on the feeder board 12 is picked up by the swing arm portion 211 and delivered to the transfer drum 212, thereby guiding the recording medium P in a direction along the outer peripheral surface of the image forming drum 22 to form an image. Hand over to drum 22.

The image forming drum 22 has a cylindrical outer shape, supports a maximum of three recording media P on the outer peripheral surface of the cylindrical portion, and conveys the recording medium P according to a rotational operation with respect to the central axis of the cylinder. Perform the transport operation. A drum heater 221 for heating the outer peripheral surface and the recording medium P is provided in the vicinity of the outer peripheral surface of the image forming drum 22. Here, the drum heater 221 is set between the delivery position of the recording medium P to the image forming drum 22 by the delivery unit 21 and the image recording position to the recording medium P by the head unit 23 in the rotation direction of the image forming drum 22. It is provided. The heating operation time and intensity of the drum heater 221 are controlled so that the recording medium P to be supported has an appropriate temperature based on the measured temperature of the outer peripheral surface of the image forming drum 22 by the temperature measuring unit (not shown). As a result, when the ink lands on the recording medium P, the curing speed on the recording medium P and the like are appropriately maintained, and a stable and high-quality image is formed. For the drum heater 221, for example, an infrared heater or a heating wire that generates heat when energized is used. The drum heater 221 may be provided inside the image forming drum 22 to heat the outer peripheral surface by heat conduction.

The head unit 23 is provided on a surface (nozzle surface) of the recording medium P facing the recording target surface of the recording medium P in the head unit 23 with respect to one recording target surface of the recording medium P that moves according to the rotation of the image forming drum 22. An image is formed by ejecting a droplet of ink from a plurality of nozzle openings provided at an appropriate timing and landing it on the recording target surface of the recording medium P.

FIG. 2 is a bottom view showing the nozzle surface of the head unit 23.
The head unit 23 includes eight inkjet heads 230, and these inkjet heads 230 are arranged in a houndstooth pattern. The eight inkjet heads 230 are arranged with some overlap in the width direction so that the nozzle openings are arranged at a predetermined interval or less in the width direction perpendicular to the transport direction of the recording medium P. As a result, by moving the recording medium P in the transport direction while the head unit 23 is fixed, it is possible to record an image in a one-pass system in which an image is recorded over the recordable width of the recording medium P.

In the inkjet recording apparatus 100 of the present embodiment, a plurality of head units 23 are arranged at predetermined intervals in the transport direction of the recording medium P, and here, four head units are arranged according to each ink of four colors. The four head units 23 output C (cyan), M (magenta), Y (yellow), and K (black) inks, respectively. As these inks, various well-known inks are used here, in which the phase changes from a gel state to a sol state when heated from room temperature and is cured by irradiation with ultraviolet rays. Further, the ink supplied to the image forming main body 20 is heated and maintained at an appropriate temperature by the ink heater 732 (see FIG. 4) and maintained in a sol state.

The irradiation unit 24 irradiates an energy ray (electromagnetic wave) having a predetermined wavelength, here, ultraviolet rays in a near-ultraviolet region (wavelength is about 400 nm), ejects the ink from the head unit 23, and lands on the recording medium P (that is, the ink). , The image formed by the ink) is cured and fixed. The irradiation unit 24 has, for example, a light emitting diode (LED) that emits ultraviolet rays, and the irradiation driving unit 74 (see FIG. 4) applies a voltage to the LED to apply a current to cause the irradiation to emit ultraviolet rays. Irradiate. The irradiation unit 24 is located at a position after the ink is ejected from the head unit 23 onto the recording medium P conveyed by the rotation of the image forming drum 22 and before the recording medium P is delivered to the delivery unit 25. Ultraviolet rays can be irradiated on P. The irradiation unit 24 is provided with a light-shielding plate 241 so as to cover the LED and the set range in order to reduce the amount of ultraviolet rays leaking outside the set range for irradiating the recording medium P with the ultraviolet rays.

The configuration in which the irradiation unit 24 emits ultraviolet rays is not limited to the LED. The irradiation unit 24 may have, for example, a mercury lamp. When the ink has a property of receiving energy rays other than ultraviolet rays and curing, a well-known light source that emits energy rays having a wavelength that cures the ink is provided instead of the above-mentioned configuration that emits ultraviolet rays.

The delivery unit 25 conveys the recording medium P after the image formation is completed and the landed ink is cured to the medium discharge unit 30. The delivery unit 25 includes a cylindrical transfer roller 251, a plurality of (for example, two) rollers 252 and 253, and a ring-shaped belt 254 supported by the rollers 252 and 253 on the inner surface. The transfer roller 251 receives the recording medium P from the image forming drum 22 and guides it onto the belt 254. The delivery unit 25 conveys the recording medium P delivered from the delivery roller 251 onto the belt 254 by moving it together with the belt 254 that orbits as the rollers 252 and 253 rotate, and sends the recording medium P to the medium discharge unit 30.

The medium discharging unit 30 stores the recording medium P sent out from the image forming main body 20 by the delivery unit 25 until it is taken out by the user. The medium discharge unit 30 has a plate-shaped discharge tray 31 and the like, and the recording medium P after image formation is placed on the discharge tray 31.

The control unit 40 controls the operations of the medium supply unit 10, the image formation main body 20, the ink supply unit 50, and the medium discharge unit 30, and sets the data of the image to be formed and the image formation by the image formation command (job). An image is formed on the recording medium P accordingly.
Of the above configurations, the media supply unit 10, the image forming drum 22 in the image forming main body 20, the transfer unit 21, the delivery unit 25, and the medium discharging unit 30 constitute a transport unit, and the transport drive unit 71 (see FIG. 4). Driven by.

The ink supply unit 50 stores inks of each color used for recording an image, and supplies the inks to the head unit 23 (inkjet head 230) of the image forming main body 20. Each configuration of the ink supply unit 50 is not particularly limited, but is, for example, arranged in a dedicated rack or the like and connected to the image forming main body unit 20 via a tube material such as a tube.

Next, a configuration related to the flow of ink from the ink supply unit 50 to the image forming main body unit 20 in the inkjet recording apparatus 100 of the present embodiment will be described.
FIG. 3 is a diagram illustrating a configuration related to an ink flow path in the inkjet recording apparatus 100 of the present embodiment.

In the inkjet recording apparatus 100, ink is supplied from the ink supply unit 50 to the image forming main body unit 20 via the ink flow path. Further, the ink flow path is provided with a gas flow path for adjusting the pressure of ink or air in the ink flow path. The ink flow path and the gas flow path are combined to form a path for supplying ink to the inkjet head 230.
The ink supply unit 50 includes a main tank 51, a filter 511, a supply pump 512, and the like.

The ink in the main tank 51 is sent to the first sub tank 260 of the image forming main body 20 by the operation of the supply pump 512. The filter 511 prevents foreign substances such as dust and dirt, and contaminants from entering the main tank 51 that is open to the atmosphere. A valve for switching whether or not ink can be supplied by the supply pump 512 may be provided between the main tank 51 and the supply pump 512 or between the supply pump 512 and the first sub tank 260.

In addition to the inkjet head 230 described above, the image forming main body 20 includes a first sub-tank 260, a degassing section 29, a liquid feed pump 262, a second sub-tank 270, a reflux section 28, and the like. A plurality of these are provided for each of the plurality of ink types described above and for each of the plurality of inkjet heads 230 forming the line head, and ink is supplied from a common main tank 51 according to the ink type.
The ink supplied from the main tank 51 to the first sub tank 260 of the image forming main body 20 by the supply pump 512 is sent to the inkjet head 230. The ink that is not ejected or leaked from the inkjet head 230 is returned to the first sub tank 260 via the reflux unit 28.

The first sub-tank 260 is an ink tank having a smaller capacity than the main tank 51 here. A first sensor 261 is provided in the first sub tank 260.

The first sensor 261 detects the amount of ink in the first sub tank 260 and outputs a detection signal to the control unit 40 (see FIG. 4). The first sensor 261 detects, for example, the amount of ink in the tank by measuring the weight of the tank in consideration of the weight of the tank itself. Alternatively, the pressure of the ink on the bottom surface of the first sub tank 260 may be measured. In these cases, the weight and pressure of the air in the first sub tank 260 can be measured instead of the ink. Alternatively, the first sensor 261 may be provided with both a liquid level sensor that detects the liquid level in the first sub tank 260 and a pressure sensor that measures the pressure of the air applied to the liquid level. The operation or non-operation of the supply pump 512 is switched according to the detected amount of ink in the first sub-tank 260, and an appropriate amount of ink is maintained in the first sub-tank 260.
Further, the ink returned from the inkjet head 230 is stored in the first sub tank 260.

When the first atmospheric release valve 273 is opened, the inside of the first sub tank 260 is opened to the atmosphere, and the pressure is set to atmospheric pressure. When the first atmospheric release valve 273 is closed, the air pressure (ink pressure) in the first sub tank 260 is adjusted according to the operation of the pneumatic pump 272.

The degassing unit 29 removes air from the ink sent from the first sub tank 260 to the second sub tank 270. The degassing unit 29 includes a degassing module 291, a circulation pump 292, a check valve 293, a vacuum pump 294, a trap 295, a degassing atmosphere release valve 296, and the like.

The degassing module 291 removes air from the inside of the ink. The degassing module 291 has, for example, a large number of hollow fiber membranes, and the air in the ink is removed by bringing the ink into contact with the outer surface of the hollow fiber membrane while drawing the inside of the hollow fiber membrane into a vacuum by a vacuum pump 294. Suction inside the hollow fiber membrane.
The circulation pump 292 returns the ink that has passed through the degassing module 291 to the front side of the degassing module 291 so that the ink can pass through the degassing module 291 a plurality of times, so that the degassing is performed more reliably.

The trap 295 is a container for storing the ink components sucked together with the air from the degassing module 291 by the vacuum pump 294. The trap 295 is formed so that ink is dropped and stored on the bottom surface by gravity and air is sucked upward by the operation of the vacuum pump 294 to separate the ink and the air, and the ink is stored in the vacuum pump 294. It is designed so that it does not enter and cause a malfunction in the vacuum pump 294. The ink in the trap 295 is appropriately discharged by opening and closing a waste liquid valve (not shown).
The degassing air release valve 296 is a valve for opening the inside of the flow path between the degassing module 291 and the vacuum pump 294 to the atmosphere. Normally, the inside of this flow path is in a state of being greatly depressurized from the atmospheric pressure, but when the degassing module 291 breaks down and a large amount of ink leaks, the degassing atmosphere release valve 296 can be opened. The pressure is quickly raised to atmospheric pressure to stop the suction operation.

The liquid feed pump 262 feeds ink from the first sub tank 260 to the second sub tank 270 via the check valve 263. As the liquid feed pump 262, conventionally known ones can be used. When the second sub tank 270 is not in communication with the atmosphere or the air tank 277, the ink pressurized by the liquid feeding operation of the liquid feeding pump 262 is supplied to the inkjet head 230 via the second sub tank 270.

The check valve 263 causes the ink to flow from the degassing portion 29 to the second sub tank 270, and prevents the ink from flowing back from the second sub tank 270 to the degassing portion 29.

The second sub-tank 270 is provided with a second sensor 271, and the second sensor 271 operates in the same manner as the first sensor 261 in the first sub-tank 260 with respect to the amount of ink and the amount of air (air pressure) in the second sub-tank 270. I do. The second sensor 271 measures the pressure of the air in the second sub tank 270 used for adjusting the back pressure using the air tank 277 and outputs it to the control unit 40.
The pressure measuring means is composed of the first sensor 261 and the second sensor 271.

The second sub tank 270 communicates with the air tank 277 when the back pressure valve 276 is opened. When the back pressure valve 276 is open, the air pressure in the air tank 277 determined according to the operation of the back pressure pump 278 causes the pressure on the nozzle surface of the inkjet head 230 to be normal (that is, the pressure related to ink ejection, etc.). A pressure difference is created between the ink pressure (in the state where it is not applied) and the atmospheric pressure to prevent unnecessary leakage of ink from the nozzle, and it is appropriate according to the pressure pattern applied when the ink is ejected. The ink is adjusted to be ejected.
The pressure in the air tank 277 can be appropriately adjusted according to the operation of the back pressure pump 278 and the opening and closing of the back pressure valve 276.

When the second atmospheric release valve 275 is opened, the second sub tank 270 communicates with the pneumatic pump 272 and the common atmospheric release valve 274. By opening the second atmosphere release valve 275 and the common atmosphere release valve 274 at the same time, the second sub tank 270 is opened to the atmosphere. Further, in a state where the second atmospheric release valve 275 is opened and the common atmospheric release valve 274 is closed, an atmospheric pressure is generated between the first sub tank 260 and the second sub tank 270 according to the operation of the pneumatic pump 272. ..
In the inkjet recording device 100 of the present embodiment, when each pump (particularly, the supply pump 512 or the pneumatic pump 272) is not operating, air does not flow through the pump and the pump is closed. If the air is not sufficiently sealed by the pump, a valve may be provided in series with the pump.

The inkjet head 230 draws ink from the inlet 231 and distributes the ink to a plurality of nozzles that eject the ink, and also discharges the not ejected ink from the outlets 232 and 233. The inlet 231 is connected to the second sub tank 270, and the outlets 232 and 233 are connected to the first sub tank 260 via the reflux portion 28, respectively. The outlets 232 and 233 are connected to the upstream side and the downstream side of a filter (not shown) provided in the ink flow path in the inkjet head 230, respectively.

The recirculation section 28 connects the outlets 232 and 233 and the first sub tank 260 with individual ink flow paths (circulation flow paths), and the circulation flow paths have the first recirculation valve 281 and the second recirculation valve 281 and the second, respectively. A recirculation valve 282 is provided to switch whether or not the ink can be circulated (whether or not the ink can be discharged).

Supply pump 512, liquid feed pump 262, circulation pump 292, vacuum pump 294, back pressure pump 278 and pneumatic pump 272 (collectively referred to as each pump, etc.) pressurize ink and / or air to flow ink, respectively. Of these, the supply pump 512, the liquid feed pump, and the circulation pump 292 constitute the liquid feed means for feeding ink during normal operation. The vacuum pump 294, the back pressure pump 278, and the pneumatic pump 272 adjust the flow of ink by adjusting the pressure of air.

The above-mentioned first recirculation valve 281, second recirculation valve 282, degassing atmosphere opening valve 296, first atmosphere opening valve 273, common atmosphere opening valve 274, second atmosphere opening valve 275, back pressure valve 276 and back pressure atmosphere opening valve. Reference numeral 279 (collectively referred to as each valve) is an electromagnetic valve whose opening / closing operation is performed electromagnetically based on the control of the control unit 40. Of these, the back pressure valve 276, the common air release valve 274, and the first air release valve 273 are normally open valves that are normally opened and closed by the supply of a predetermined drive voltage from the control unit 40. The other valves are normally closed valves that are normally closed and opened by the supply of a predetermined drive voltage from the control unit 40.
Each of these valves and each pump constitutes a means for opening and closing the path.

FIG. 4 is a block diagram showing a functional configuration of the inkjet recording device 100 of the present embodiment.

As described above, the inkjet recording apparatus 100 includes a supply pump 512, a liquid feed pump 262, a circulation pump 292, a vacuum pump 294, a back pressure pump 278, a pneumatic pump 272, and a degassing atmosphere release valve 296. , 1st air opening valve 273, common air opening valve 274, 2nd air opening valve 275, back pressure valve 276, back pressure air opening valve 279, 1st recirculation valve 281 and 2nd recirculation valve 282. A first sensor 261 and a second sensor 271 and a drum heater 72 and the like are provided. Further, the inkjet recording device 100 includes a control unit 40 (sealing defect detecting means, open / close control means, heating control means), a transport drive unit 71, a head drive unit 731, an ink heater 732 (heating means), and irradiation. It includes a drive unit 74, a communication unit 61, an operation display unit 62, a bus 69, and the like.

The control unit 40 controls the overall operation of the inkjet recording device 100 in an integrated manner. The control unit 40 includes a CPU 41 (Central Processing Unit), a RAM 42 (Random Access Memory), a ROM 43 (Read Only Memory), a memory 44, and the like.

The CPU 41 performs various arithmetic processes to control the transfer of the recording medium in the inkjet recording apparatus 100, the opening / closing operation of each valve, the liquid feeding operation of each pump, the ink ejection operation, the maintenance operation, and the like. This maintenance operation includes a flow path leakage detection process for detecting sealing defects (leakage) in various places such as an ink flow path. Further, the CPU 41 performs various processes related to image recording based on the image data, the status signal of each part, the clock signal, and the like according to the program read from the ROM 43.

The RAM 42 provides the CPU 41 with a working memory space and stores temporary data.
The ROM 43 stores a control program, initial setting data, and the like. The control program includes a program related to the above-mentioned flow path leakage detection process. Further, the ROM 43 includes a non-volatile memory that can be overwritten and updated, and can store setting data and the like that are set and maintained at any time. The memory 44 includes a RAM for temporarily storing image data to be recorded.

The transport drive unit 71 transmits a drive signal for rotating the rotation motor of the image forming drum 22 and the motor for rotating any of the rollers of the feeder board 12 and the delivery unit 25 in appropriate directions and speeds. Generate and output. The transport drive unit 71 outputs a drive signal according to the rotation direction and rotation speed of each of the motors based on the control signal from the control unit 40.

The head drive unit 731 generates and outputs a drive voltage signal that deforms (drives) the pressure chamber (piezoelectric element) in order to properly eject ink from each nozzle of the inkjet head 230. The head drive unit 731 selects a voltage waveform pattern stored in advance based on the control signal from the control unit 40 to generate a power-amplified drive voltage signal, and each of the head drive units 731 is generated according to the image data input from the memory 44. Whether or not the drive voltage signal can be output to the piezoelectric element is switched.
The wiring related to the head drive unit 731 is formed together with the ink flow path in the inkjet head 230, and is partially formed separately.

The ink heater 732 keeps the ink in a sol state by heating the ink to an appropriate temperature in the image forming main body 20 such as in the head unit 23, and keeps the viscosity in an appropriate state at the time of ejection. The ink temperature is estimated from the temperature measured by the temperature measuring unit (not shown) near the nozzle of the inkjet head 230, and the operating state of the ink heater 732 is determined by the control unit 40 (heating control means) based on the temperature. Be controlled.

The irradiation drive unit 74 applies a predetermined voltage to the LED of the irradiation unit 24 in response to a control signal from the control unit 40 to cause a current to flow through the LED to emit ultraviolet rays.

The communication unit 61 is a communication interface that controls the communication operation with the external device. The communication interface includes one or a plurality of communication interfaces corresponding to various communication protocols, such as a LAN board and a LAN card. The communication unit 61 acquires the image data to be recorded and the setting data (job data) related to the image recording from the external device based on the control of the control unit 40, and also transmits the status information and the like to the external device. Can be done.

The operation display unit 62 displays the status of the inkjet recording device 100, the operation menu, and the like in response to the control signal from the control unit 40, and also receives an input operation from the outside such as a user and outputs it to the control unit 40. The operation display unit 62 includes, for example, a liquid crystal display unit in which a touch sensor as an operation receiving means is provided so as to overlap with a display screen as a display means. The control unit 40 displays the status, various menus for receiving commands by the touch sensor, and the like on the liquid crystal display unit, and provides information on the contents and position of the displayed menu and the user's touch operation detected by the touch sensor. A control operation is performed in which each part of the inkjet recording apparatus 100 performs the corresponding processing.

The bus 69 is a path for electrically connecting each of the above configurations to exchange signals.

In addition to these configurations, the inkjet recording device 100 detects an image quality abnormality (defectiveness) of an image formed on a notification operation unit such as an LED lamp and / or a beep sound generation unit used for the notification operation and a recording medium. It may be provided with a reading unit such as a line sensor or a mounting abnormality detection sensor that detects that the supplied recording medium is not normally mounted on the transport surface.

Next, the leak detection operation in the inkjet recording apparatus 100 of the present embodiment will be described.
The inkjet recording device is provided with a large number of ink flow paths and gas flow paths (paths), and if a defect (sealing defect) occurs in itself or the connection portion of a plurality of routes, ink or air leaks out. Ink and air are not sent normally, and pressure is not applied properly, which leads to waste of ink, dirt on the peripheral part, and failure. These defects include late ones and early ones at the time of manufacturing and assembling, and in particular, initial defects need to be surely eliminated.

In the inkjet recording device 100 of the present embodiment, when the inkjet recording device 100 is assembled, an inspection related to detection of leaks in these paths is performed using air before introducing ink into the ink flow path. Here, the path is partially sealed by a predetermined range, and the air inside the sealed path is changed to a set pressure P0 (first pressure) positive or negative with respect to the atmospheric pressure to obtain a pressure. The presence or absence of a leak is detected depending on whether or not the set pressure is normally reached and whether or not the pressure after reaching the set pressure does not change significantly (pressure change) in the direction of returning to the atmospheric pressure within the reference time.

A pump (pressure applying means) for supplying ink is used as it is for setting the air pressure of these airs, and a first sensor 261 and a second sensor 271 (pressure measuring means) are used for measuring the air pressure. Be done. Based on the measurement results of these pressure measuring means, the control unit 40 (sealing defect detecting means) determines the presence or absence of a leak (sealing defect, leak).

FIG. 5 is a diagram showing an example of the time change of the air pressure measured by the first sensor 261 and the second sensor 271 at the time of leak inspection.

After the predetermined path range (predetermined range) is sealed in the atmospheric pressure state, when the pump that sends air to the sealed portion is operated, the air pressure rises, and as shown in FIG. 5 (a), Here, the pressure is raised to the set atmospheric pressure P0. When the operation of the pump is stopped at that stage, if there is no leak, the air pressure does not drop significantly during the reference time Δt (r1), but if there is a leak, the air pressure decreases. (Approaching atmospheric pressure: r2). Here, if there is an atmospheric pressure change (here, a decrease in atmospheric pressure) of the threshold value ΔP or more during the reference time Δt, it is determined that there is a leak in the path in the sealing section.
Similarly, when the air pressure in the sealing section is sucked by a pump to reduce the pressure, the presence or absence of a leak is determined by detecting an increase in air pressure equal to or higher than the threshold value ΔP within the reference time Δt. This threshold value ΔP is set to a magnitude of change that does not occur due to fluctuations in atmospheric pressure due to vibration of air in the path or the like. Further, it is appropriately set for each path portion based on the difference between the set pressure P0 of the sealing portion and the atmospheric pressure.
If the location where air leakage occurs is large, it may not be possible to raise the air pressure to the set air pressure P0. In this case, as shown in FIG. 5 (b), the maximum operating time Tsmax of the pump is set, and if the set atmospheric pressure P0 is not reached by the time when the maximum operating time Tsmax elapses (r3). , It is determined that a leak has occurred in the path within the sealing section.

In the inkjet recording device 100, air easily flows in and out from each nozzle opening of the inkjet head 230, and it is difficult to seal the ink jet head 230. Therefore, this inspection is performed by temporarily providing a bypass path connecting the second sub-tank 270 and the reflux portion 28 at the stage before mounting the inkjet head 230.

6 and 7 are flowcharts showing a control procedure by the control unit 40 of the flow path leakage detection process executed by the inkjet recording apparatus 100 of the present embodiment.

This flow path leakage detection process is started based on a predetermined input operation to the operation display unit 62, for example, an activation command for the flow path leakage detection process further selected from the maintenance menu.
When the flow path leakage detection process is started, first, as shown in FIG. 7, the control unit 40 closes the first atmosphere release valve 273, the first return valve 281 and the second return valve 282, and the common atmosphere release valve 274 is opened (step S101).

The control unit 40 operates the pneumatic pump 272, and while checking the measurement data of the first sensor 261, the liquid feed pump 262 (check valve 263) passes from the main tank 51 through the first sub tank 260 and the degassing unit 29. The air in the path to (referred to as section A) is sucked (step S102). The control unit 40 determines whether or not the atmospheric pressure in the path has reached the set atmospheric pressure P01 based on the measurement data of the first sensor 261 (step S103), and if it is determined that the atmospheric pressure has reached the set atmospheric pressure P01 (step S103, “” YES ”), the process proceeds to step S107. If it is determined that the pump has not reached (“NO” in step S103), the control unit 40 determines whether or not the predetermined maximum operating time of the pneumatic pump 272 has elapsed from the start of the operation of the pneumatic pump 272. Is determined (step S104). If it is determined that the elapse has not occurred (“NO” in step S104), the process of the control unit 40 returns to step S103. If it is determined that the elapse has passed (“YES” in step S104), the control unit 40 stops the operation of the pneumatic pump 272 (step S105), determines that there is a leak in the section A (step S105). S106), the process is shifted to step S131 (A, FIG. 7).

When the process proceeds to step S107, the control unit 40 stops the operation of the pneumatic pump 272 (step S107). The control unit 40 acquires the pressure (atmospheric pressure) measured by the first sensor 261 and determines whether or not the measured atmospheric pressure rises from the set atmospheric pressure P01 by a threshold value ΔP1 or more (or whether the atmospheric pressure becomes P01 + ΔP1 or more). ) Is determined (step S108). If it is determined that the height has increased (“YES” in step S108), the process of the control unit 40 shifts to step S106.

When it is determined that the atmospheric pressure has not risen by the threshold value ΔP1 or more (the atmospheric pressure is not P01 + ΔP1 or more) (“NO” in step S108), the control unit 40 stops the operation of the pneumatic pump 272. It is determined whether or not the elapsed time exceeds the predetermined reference time Δt (step S109). If it is determined that the reference time Δt has not been exceeded (“NO” in step S109), the processing of the control unit 40 returns to step S108.

When it is determined that the elapsed time exceeds the predetermined reference time Δt (“YES” in step S109), the control unit 40 determines that there is no leak in the section A (step S110).

The control unit 40 closes the back pressure valve 276 and the second atmosphere release valve 275 (step S111). Further, at this time, the first reflux valve 281 and the second reflux valve 282 remain closed.

The control unit 40 operates the liquid feed pump 262, and while checking the measurement data of the second sensor 271, the first return valve 281 passes from the check valve 263 to the second sub tank 270 and the bypass path instead of the inkjet head 230. Air is supplied and pressurized in the path (referred to as section B) to the second return valve 282 (step S112). The control unit 40 determines whether or not the atmospheric pressure in the path has reached the set atmospheric pressure P02 based on the measurement data of the second sensor 271 (step S113), and if it is determined that the atmospheric pressure has reached the set atmospheric pressure P02 (step S113, “” YES ”), the process shifts to step S117. If it is determined that the liquid has not been reached (“NO” in step S113), the control unit 40 determines whether or not the predetermined maximum operating time of the liquid feeding pump 262 has elapsed from the start of the operation of the liquid feeding pump 262. (Step S114). If it is determined that the elapse has not occurred (“NO” in step S114), the process of the control unit 40 returns to step S113. If it is determined that the elapse has passed (“YES” in step S114), the control unit 40 stops the operation of the liquid feed pump 262 (step S115), determines that there is a leak in the section B (step S115). S116), and then the process shifts to step S131 (A, FIG. 7).

When the process shifts to the process of step S117, the control unit 40 stops the operation of the liquid feed pump 262 (step S117). The control unit 40 acquires the pressure (atmospheric pressure) measured by the second sensor 271 and determines whether or not the measured atmospheric pressure has dropped from the set atmospheric pressure P02 by the threshold value ΔP2 or more (or whether the atmospheric pressure has become P02 + ΔP2 or less). ) Is determined (step S118). If it is determined that the height has risen (“YES” in step S118), the process of the control unit 40 shifts to step S116.

When it is determined that the atmospheric pressure has not decreased by the threshold value ΔP2 or more (the atmospheric pressure is not P02 + ΔP2 or less) (“NO” in step S118), the control unit 40 stops the operation of the liquid feed pump 262. It is determined whether or not the elapsed time exceeds the predetermined reference time Δt (step S119). If it is determined that the reference time Δt has not been exceeded (“NO” in step S119), the process of the control unit 40 returns to step S118.

When it is determined that the elapsed time exceeds the predetermined reference time Δt (“YES” in step S119), the control unit 40 determines that there is no leak in the section B (step S120).

Entering FIG. 7, the control unit 40 closes the common atmosphere release valve 274 and opens the second atmosphere release valve 275 (step S121). The control unit 40 operates the pneumatic pump 272 to acquire the pressure (atmospheric pressure) measured by the second sensor 271 and covers the range from the pneumatic pump 272 to the second sub tank 270 (referred to as section C). In addition to the previous section B, air is supplied by including it in the pressurized supply range of air (step S122).

The control unit 40 determines whether or not the value of the atmospheric pressure measured by the second sensor 271 has reached the set atmospheric pressure P03 (step S123), and if it is determined that the value has reached (“YES” in step S123). , The process shifts to step S127. If it is determined that the pump has not reached (“NO” in step S123), the control unit 40 determines whether or not the predetermined maximum operating time of the pneumatic pump 272 has elapsed from the start of the operation of the pneumatic pump 272. (Step S124). If it is determined that the elapse has not occurred (“NO” in step S124), the process of the control unit 40 returns to step S123. If it is determined that the elapse has passed (“YES” in step S124), the control unit 40 stops the operation of the pneumatic pump 272 (step S125), and determines that there is a leak in the section C (step S126). ). Then, the process of the control unit 40 shifts to step S131.

When the process shifts to the process of step S127, the control unit 40 stops the operation of the pneumatic pump 272 (step S127). The control unit 40 acquires the pressure (atmospheric pressure) measured by the second sensor 271 and determines whether or not the measured atmospheric pressure has dropped from the set atmospheric pressure P03 by the threshold value ΔP3 or more (or whether the atmospheric pressure has become P03 + ΔP3 or less). ) Is determined (step S128). If it is determined that the height has increased (“YES” in step S128), the process of the control unit 40 shifts to step S126.

When it is determined that the atmospheric pressure has not decreased by the threshold value ΔP3 or more (the atmospheric pressure is not P03 + ΔP3 or less) (“NO” in step S128), the control unit 40 stops the operation of the pneumatic pump 272. It is determined whether or not the elapsed time exceeds the predetermined reference time Δt (step S129). If it is determined that the reference time Δt has not been exceeded (“NO” in step S129), the process of the control unit 40 returns to step S128.

When it is determined that the elapsed time exceeds the predetermined reference time Δt (“YES” in step S129), the control unit 40 determines that there is no leak in the section C (step S130). Then, the process of the control unit 40 shifts to step S131.

When the process shifts to the process of step S131, the control unit 40 causes the operation display unit 62 to display the detection result relating to the presence or absence of a leak in each section (step S131), and the control unit 40 ends the flow path leakage detection process. ..

By the above flow path leakage detection process, the leak of the path portion (including the path for air by adjusting the back pressure) related to the flow of ink in the ink supply section 50 and the image forming main body section 20 is divided into three blocks. It will be detected. Defects on the degassing side of the inkjet head 230 and the degassing section 29 are individually and independently inspected by a well-known method. Further, when inspecting the route from the second sub tank 270 to the back pressure pump 278 in the same manner, the back pressure valve 276 is opened, the back pressure air release valve 279 is closed, and the back pressure atmosphere release valve 279 is closed during the inspection of the section B. The back pressure pump 278 may be stopped so that air leakage from the back pressure pump 278 does not occur.
Each process of steps S101 to S130 constitutes a discharge defect detection step.

FIG. 8 is a flowchart showing a control procedure by the control unit 40 of the flow path monitoring process executed by the inkjet recording device 100.
This flow path monitoring process is continuously or periodically executed during the operation of the inkjet recording apparatus 100 after the user starts using the ink flow path and the ink is introduced into the ink flow path.

When the flow path monitoring process is started, the control unit 40 acquires the measured values of the first sensor 261 and the second sensor 271 (step S201), and obtains an abnormal value whose atmospheric pressure value is not within the preset range. It is determined whether or not it is shown or whether or not it shows an abnormal change with respect to the history of the atmospheric pressure change so far (step S202). The preset range at this time may be selected from a plurality of types according to the operating state of the inkjet recording device 100. Further, the abnormal change may be an absolute value of the amount of change, or may be discriminated based on a predetermined standard in consideration of the rate of change, the degree of change in the latest predetermined number of times, and the like.

When it is determined that the atmospheric pressure value is not an abnormal value and there is no abnormality in the atmospheric pressure change (“NO” in step S202), the control unit 40 waits for a predetermined time and starts from the acquisition of the previous measured value. It is determined whether or not the predetermined time has elapsed (step S203). If it is determined that the predetermined time has not elapsed (“NO” in step S203), the control unit 40 repeats the process of step S203. During this standby, the control unit 40 may store the previously acquired measured value as historical data, and may calculate the latest average value (moving average, etc.), the rate of change in pressure, and the like. If it is determined that the predetermined time has elapsed (“YES” in step S201), the process of the control unit 40 returns to step S201.

If it is determined in the determination process of step S202 that the atmospheric pressure value is an abnormal value or that there is an abnormality in the atmospheric pressure change (“YES” in step S202), the control unit 40 performs a predetermined notification operation. Let it be done (step S211). The notification operation may be a predetermined display on the operation display unit 62, or may be one that causes the operation display unit 62 to perform a predetermined operation when the LED for voice output or notification is provided.

The control unit 40 determines whether or not it is necessary to stop the currently executing operation such as image recording or ink supply operation (step S212), and if it is determined that it is not necessary to stop the operation, the control unit 40 determines. (“NO” in step S212), the process of the control unit 40 shifts to step S203. When it is determined that it is necessary to stop the operation (“YES” in step S212), the control unit 40 stops the operation (step S213) and ends the flow path monitoring process.

Further, even after the ink is introduced, the leak can be inspected by changing the pressure of the ink in the same manner as the above-mentioned flow path leakage detection process. In this case, it is necessary to appropriately heat and inspect the ink so that it is kept in a sol state in the flow path.
Further, in the section A, when it is difficult to prevent the ink of the first sub tank 260 from being sucked together with the air when the pressure is reduced by the suction operation of the pneumatic pump 272, the liquid feed pump 262 and the pneumatic pump 272 are used. Leakage may be detected by operating the supply pump 512 in the stopped state and pressurizing the ink in the section from the supply pump 512 to the liquid feed pump 262.
Further, since the inkjet head 230 is attached after the introduction of the ink, leakage from the nozzle opening occurs. In this case, the viscosity of the ink is higher than that of air, and it is possible to detect the presence or absence of leakage in section B even if ink leakage is taken into consideration. It is preferable to reduce it. Further, when ink leaks from the nozzle opening, it is preferable to provide a waste liquid tray or the like for receiving the leaked ink.

In these cases, the ink pressure P0L (second pressure) at the time of pressurization / depressurization is set to a value different from the set atmospheric pressure P0 (P01 to P03) in consideration of the difference between the viscosity of the ink and the viscosity of the air. The reference time ΔtL and the threshold value ΔPL are set to different values (different standards) from the reference time Δt and the threshold value ΔP (ΔP1 to ΔP3), respectively. Therefore, when started in response to a user command operation, an appropriate inspection is selected depending on whether or not ink has been introduced. In addition to the case where the user (operator) makes this selection, the control unit 40 may automatically determine the case where it is possible to confirm that the ink is not introduced in the path.

As described above, the inkjet recording apparatus 100 of the present embodiment has a path for supplying ink to the nozzle, each pump for applying pressure to the fluid in the path, and a first measurement for measuring the pressure in the path. The first sensor 261 and the second sensor 271 and the first sensor 261 and the second sensor 271 when the gas in the path is set to a set pressure P0 (P01 to P03) different from the pressure outside the path by each pump in a state where ink is not introduced into the path. / Or a control unit 40 as a sealing defect detecting means for detecting a sealing defect in the path based on the measurement result relating to the gas pressure by the second sensor 271.
In this way, since air is used to detect the sealing defect of the path related to the ink supply before the ink is introduced, even if there is a sealing defect, the ink does not actually leak. Therefore, post-treatment of the leaked ink becomes unnecessary, and it is possible to significantly reduce the time and effort. In particular, since it is possible to avoid a situation in which the circuit board is short-circuited due to ink leakage and needs to be replaced, the cost and labor increase such as wasting a normally manufactured circuit board due to an initial failure. It can be avoided. That is, it is possible to detect a sealing defect related to the ink flow path configuration in the inkjet recording device with simple and easy labor.

Further, each valve and each pump for partially sealing the path in a predetermined range are provided, and the control unit 40 operates as an opening / closing control means for controlling the opening / closing operation of each of these valves and each pump, resulting in poor sealing. The control unit 40 as a detection means detects a sealing defect within a predetermined range. As a result, the location of the detection omission can be narrowed down within the predetermined range, so that the identification of the leak location when a leak is detected becomes easier and easier, and the replacement or repair of the leak location becomes easier. Can be done.

Further, the control unit 40 as the sealing defect detecting means detects the sealing defect based on the pressure change after the gas in the path is set to the set atmospheric pressure P0 (P01 to P03). That is, since a large amount of gas does not flow out immediately due to a minute sealing leak, etc., by detecting the pressure change within the reference time Δt, the sealing can be performed easily and more reliably without complicating the processing and the judgment criteria. It is possible to detect a stop failure.

In addition, each pump includes a liquid feed pump 262 that feeds ink in an ink flow path through which ink flows in the path. That is, since the pump used for inking the ink can be used as it is for applying the pressure of air, no additional configuration for inspection is required, and additional cost and additional space can be eliminated.

In addition, the inkjet recording device 100 includes an ink heater 732 that heats at least a part of the ink flow path through which ink flows. In this way, even in the inkjet recording apparatus 100 that requires heating of the ink, it is possible to inspect the sealing defect by using gas (air) without the need for heating the ink or adjusting the temperature. The inspection can be simplified.

Further, the path includes an ink flow path through which ink flows and a gas flow path for adjusting the flow of ink in the ink flow path. That is, by inspecting the sealing defect using gas (air), not only the part where the ink is introduced but also the sealing defect of the gas flow path for adjusting the pressure of the ink can be easily detected. Therefore, it is possible to further simplify the inspection of sealing defects.

Each pump also includes a pneumatic pump 272 that regulates the pressure of the gas in the gas flow path. That is, not only the pump for sending ink but also the pump for adjusting the pressure of air can be used as it is to detect the sealing failure of the ink flow path in addition to the gas flow path. The detection operation is simplified.

Further, the control unit 40 as a sealing defect detecting means sets the ink in the path to a set pressure (P0L) different from the set atmospheric pressure P0 (P01 to P03) by each pump in a state where the ink is introduced into the path. In this case, a sealing defect in the path is detected based on the measurement result relating to the ink pressure by the first sensor 261 and / or the second sensor 271. That is, after the ink is introduced, it is possible to detect an ink leakage defect due to timekeeping deterioration or the like as usual. Further, in this case, since the sealing defect is detected at a pressure setting different from the detection of the sealing defect due to the gas, a state in which the ink leakage cannot be detected as compared with the conventional case does not occur. In addition, by performing the inspection under appropriate conditions and standards for each inspection, an unnecessary load is not applied to the route, and the inspection does not require a great deal of labor.

Further, the control unit 40 as the sealing defect detecting means is based on different criteria depending on whether the gas in the path is set to the set atmospheric pressure P0 (P01 to P03) and the ink in the path is set to the pressure P0L. To determine if there is a sealing defect. That is, since the sealing defect is detected by an appropriate standard in consideration of the difference in viscosity between the air and the ink, the sealing defect can be appropriately detected in any case.

Further, an ink heater 732 for heating at least a part of the ink flow path through which ink flows is provided, and the control unit 40 operates as a heating control means for controlling the operation of the ink heater 732, and controls as a heating control means. The unit 40 does not operate the ink heater 732 when detecting a sealing defect in a state where ink is not introduced into the path.
As a result, even in an inkjet recording device that uses a type of ink that requires heating for flow and ejection, it is easy and quick to inspect for sealing defects, especially in the initial state, without the need for such heating. Can be done.

Further, an operation display unit 62 (display means) for displaying the detection result by the control unit 40 as a sealing defect detecting means is provided. As a result, the inspection result can be easily and appropriately shown to the person who executes the inspection and the manager at the time of the inspection.

Further, by using the above-mentioned abnormality detection method of the inkjet recording device, ink does not actually leak even if there is a sealing defect due to an initial defect or the like, so that post-treatment of the leaked ink becomes unnecessary. It is possible to significantly reduce the time and effort. In particular, since it is possible to avoid a situation in which the circuit board is short-circuited due to ink leakage and needs to be replaced, the cost and labor increase such as wasting a normally manufactured circuit board due to an initial failure. It can be avoided. That is, it is possible to detect a sealing defect related to the ink flow path configuration in the inkjet recording device with simple and easy labor.

The present invention is not limited to the above embodiment, and various modifications can be made.
For example, in the above embodiment, the inspection has been described as the inspection at the time of manufacturing and assembling the inkjet recording device 100, but the same inspection is performed when the ink is discharged at the time of exchanging the flow path component or the inkjet head 230. Can be done.

Further, in the above embodiment, the bypass path is temporarily attached before the inkjet head 230 is attached to perform the inspection, but the nozzle opening of the inkjet head 230 is sealed as in the inspection after the ink is introduced. The inspection may be performed after the inkjet head 230 is attached.
Alternatively, a solenoid valve is further provided adjacent to the inlet 231 so that only the portion from the second sub tank 270 to the front of the inlet 231 is included in the section B, and the first recirculation valve 281 and the second recirculation valve 282 are included in the outlet 232. By forming in the immediate vicinity of 233, the section A may include almost all of the reflux portion 28.

Further, the arrangement and number of each valve are not limited to the above-described embodiment. It may be appropriately changed depending on the arrangement and presence / absence of the filter, the degassing portion 29, and the like. Further, in an inkjet recording device in which a flexible ink storage member is used as a configuration for generating back pressure, a bypass flow path of the ink storage member and ink or air to the ink storage member and the bypass flow path are used. A valve for switching whether or not to distribute the ink may be provided, and the inside of the ink storage member may be excluded from the pressurization / depressurization target (that is, the inspection target) to inspect for leakage.

Further, in the above embodiment, leaks are detected by dividing into sections A to C, but when valves and pumps are arranged so that the entire ink flow path can be inspected at once, they are inspected collectively. May be done.

Further, in the above embodiment, the case of using an ink whose phase changes between the sol state and the gel state depending on the temperature has been described, but the ink jet recording apparatus using not only such ink but also various other inks has been described. The present invention can also be applied. In such a case, it is not always necessary to provide a configuration for heating the entire ink flow path, and a configuration for heating only a part (at least a part) around the nozzle may be used. Alternatively, an inkjet recording device having a configuration that does not include any heating means may be used.

Further, in the above embodiment, it has been described that it is not necessary to heat the path when detecting a leak due to air, but in consideration of the influence of the heat of the path itself (expansion, strain, etc.), the path is heated. Leakage detection by air may be performed.

Further, in the above embodiment, the leak is detected by using ordinary air, but by detecting the leak by using a colored gas, it is possible to make it easier to identify the leaked part. good.

Further, in the above-described embodiment, the control unit 40 performs all the control operations related to the inspection, but it is also possible for the user (operator) to switch the operation of each valve or the operation of each pump by himself / herself. Further, only the pressure measurement value may be simply displayed on the operation display unit 62, and the operator may make a judgment regarding the leakage state, and the operator may further set the pressure for such a judgment. It may be possible to perform an input operation of a switching command.
In addition, specific contents such as the configuration, structure, control contents and procedures shown in the above-described embodiment can be appropriately changed without departing from the spirit of the present invention.

10 Medium supply unit 11 Supply tray 12 Feeder board 121, 122 Roller 123 Belt 20 Image forming main body 21 Delivery unit 211 Swing arm 212 Delivery drum 22 Image forming drum 221 Drum heater 23 Head unit 230 Inkjet head 231 Inlet 232, 233 Outlet 24 Irradiation unit 241 Light-shielding plate 25 Delivery unit 251 Delivery roller 252, 253 Roller 254 Belt 28 Refrigeration unit 281 First recirculation valve 282 Second recirculation valve 29 Degassing unit 291 Degassing module 292 Circulation pump 293 Check valve 294 Vacuum pump 295 Trap 296 Degassing air release valve 30 Medium discharge unit 31 Discharge tray 40 Control unit 41 CPU
42 RAM
43 ROM
44 Memory 50 Ink supply unit 51 Main tank 511 Filter 512 Supply pump 61 Communication unit 62 Operation display unit 69 Bus 71 Conveyance drive unit 72 Drum heater 731 Head drive unit 732 Ink heater 74 Irradiation drive unit 100 Inkjet recording device 260 1st sub tank 261 1st sensor 262 Liquid feed pump 263 Check valve 270 2nd sub tank 271 2nd sensor 272 Pneumatic pump 273 1st atmosphere release valve 274 Common atmosphere release valve 275 2nd atmosphere release valve 276 Back pressure valve 277 Air tank 278 Back pressure pump 279 Back pressure air release valve P Recording medium

Claims (11)

A path for supplying ink to the nozzle, a pressure applying means for applying pressure to the fluid in the path, a pressure measuring means for measuring the pressure in the path, and a state in which no ink is introduced into the path. , When the pressure applying means sets the gas in the path to a first pressure different from the pressure outside the path, the sealing failure in the path is determined based on the measurement result relating to the pressure of the gas by the pressure measuring means. An inkjet recording apparatus comprising: a sealing defect detecting means for detecting, and the pressure applying means includes a liquid feeding means for feeding an ink in an ink flow path through which an ink flows in the path. An opening / closing means that partially seals the path in predetermined ranges,
An opening / closing control means that controls the opening / closing operation of the opening / closing means,
With
The inkjet recording apparatus according to claim 1, wherein the sealing defect detecting means detects the sealing defect within the predetermined range. The inkjet according to claim 1 or 2 , wherein the sealing defect detecting means detects the sealing defect based on a pressure change after the gas in the path is set to the first pressure. Recording device. The inkjet recording apparatus according to any one of claims 1 to 3 , further comprising a heating means for heating at least a part of an ink flow path through which ink flows. The passage according to any one of claims 1 to 4 , wherein the path includes an ink flow path through which ink flows and a gas flow path for adjusting the flow of ink in the ink flow path. Inkjet recording device. The inkjet recording apparatus according to claim 5, wherein the pressure applying means includes a device for adjusting the pressure of a gas in the gas flow path. The sealing defect detecting means measures the pressure when the ink in the path is set to a second pressure different from the first pressure by the pressure applying means in a state where the ink is introduced into the path. The inkjet recording apparatus according to any one of claims 1 to 6 , wherein a sealing defect in the path is detected based on a measurement result relating to an ink pressure by means. The sealing defect detecting means seals the seal based on different criteria depending on whether the gas in the path is the first pressure or the ink in the path is the second pressure. The inkjet recording apparatus according to claim 7 , wherein the presence or absence of defects is determined. A heating means for heating at least a part of the ink flow path through which ink flows in the path and a heating control means for controlling the operation of the heating means are provided, and the heating control means does not introduce ink into the path. The inkjet recording apparatus according to claim 7 or 8 , wherein the heating means is not operated when the sealing defect is detected by the sealing defect detecting means in the state. The inkjet recording apparatus according to any one of claims 1 to 9 , further comprising a display means for displaying the detection result by the sealing defect detecting means. A method for detecting an abnormality in an inkjet recording apparatus including a path for supplying ink to a nozzle, a pressure applying means for applying pressure to a fluid in the path, and a pressure measuring means for measuring the pressure in the path. In the state where the ink is not introduced into the path, the pressure of the gas by the pressure measuring means is set to a first pressure different from the pressure outside the path by the pressure applying means. The pressure applying means includes a sealing defect detecting step of detecting a sealing defect in the path based on the measurement result, and the pressure applying means is a liquid feeding means for feeding ink in the ink flow path through which the ink flows in the path. A method for detecting anomalies in an inkjet recording apparatus, which comprises.

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