Liquid delivery device and inkjet recording device

Abstract

The present application provides a liquid delivery device and an inkjet recording device. The liquid delivery device includes a flow path, a pump, a leakage detection unit, a pump power supply circuit, and a latch circuit. The leakage detection unit detects leakage of the liquid in the flow path and the pump, and outputs a leakage detection signal. The pump power supply circuit turns on / off the power supply of the pump. The latch circuit receives and holds the leakage detection signal, and sends the leakage detection signal to the pump power supply circuit to turn off the power supply of the pump.

Description

Technical Field

[0001] This invention relates to liquid delivery devices and inkjet recording devices. Background Technology

[0002] Inkjet recording devices, which record images by spraying ink onto thin recording media such as paper, such as printers and copiers, are widely used because they can record high-resolution images. In image forming apparatuses that include such inkjet recording devices, measures are taken to detect and monitor liquid leaks to prevent contamination inside and outside the apparatus caused by leaks of liquids such as ink and cleaning fluid. Summary of the Invention

[0003] The purpose of this invention is to provide a liquid delivery device and an inkjet recording device that can appropriately stop the delivery of liquid in the event of leakage.

[0004] The liquid delivery device of the first structure of the present invention includes a flow channel, a pump, a leakage detection unit, a pump power supply circuit, and a latching circuit. The flow channel allows liquid to flow through it. The pump is connected to the flow channel, causing the liquid to move within the flow channel. The leakage detection unit detects leakage of the liquid in the flow channel and the pump, and outputs a leakage detection signal. The pump power supply circuit switches the power supply to the pump on / off. The latching circuit receives and holds the leakage detection signal, and sends the leakage detection signal to the pump power supply circuit to disconnect the power supply to the pump.

[0005] According to the first structure of the present invention, in the event of a liquid leak, the power supply to the pump is disconnected by the latching circuit that receives the leak detection signal via the pump power supply circuit. That is, even if the detection state is deactivated due to an adverse situation occurring in the leak detection unit after the leak is detected, the initially detected leak state is maintained by the latching circuit. Therefore, the restart of the pump can be stopped, and the resumption of liquid delivery can be prevented. Thus, in the event of a leak, liquid delivery can be appropriately stopped. Attached Figure Description

[0006] Figure 1 This is a schematic front sectional view of an inkjet recording apparatus according to one embodiment of the present invention. Figure 2 yes Figure 1 A top view of the area surrounding the recording section of an inkjet recording device. Figure 3 It means Figure 1 A diagram illustrating the structure of the ink supply system and control system surrounding the recording section of an inkjet recording device. Figure 4 It means Figure 1A diagram illustrating the structure of the ink discharge system and control system surrounding the recording section of an inkjet recording device. Figure 5 It means Figure 1 A block diagram of the structure of an inkjet recording device related to leakage detection. Figure 6 It means Figure 1 A flowchart illustrating an example of leakage detection processing in an inkjet recording device. Detailed Implementation

[0007] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the present invention is not limited to the following descriptions.

[0008] Figure 1 This is a schematic front sectional view of the inkjet recording device 1 according to the embodiment. Figure 2 yes Figure 1 A top view of the periphery of the recording section 5 of the inkjet recording apparatus 1. The inkjet recording apparatus 1 is, for example, an inkjet recording printer. Figure 1 and Figure 2 As shown, the inkjet recording device 1 includes a device body 2, a sheet supply unit 3, a sheet transport unit 4, a recording unit 5, a drying unit 6, and a control unit 7.

[0009] The sheet supply unit 3 is, for example, located at the lower part of the device body 2. The sheet supply unit 3 contains multiple sheets (recording media) S, and separates and feeds out the sheets S one by one during recording.

[0010] The sheet transport unit 4 is positioned downstream of the sheet supply unit 3 in the sheet transport direction, transporting the sheet S sent from the sheet supply unit 3. The sheet transport unit 4 transports the sheet S to the recording unit 5 and the drying unit 6, and then discharges the recorded and dried sheet S to the sheet discharge unit 21. Furthermore, the sheet transport unit 4 includes, for example, a flip transport unit 4r. In the case of double-sided recording, the sheet transport unit 4 distributes the sheet S, after recording and drying on the first side, to the flip transport unit 4r, and then transports the sheet S, which has been flipped from side to side by changing the transport direction, back to the recording unit 5 and the drying unit 6.

[0011] The sheet transport unit 4 includes a first belt transport unit 41 and a second belt transport unit 42. The first belt transport unit 41 has a first conveyor belt 411 formed in a ring shape. The second belt transport unit 42 has a second conveyor belt 421 formed in a ring shape. The first belt transport unit 41 and the second belt transport unit 42 transport the sheet S by adsorbing and holding it on the outer surface (upper surface) of the upper side of the first conveyor belt 411 and the second conveyor belt 421, respectively. The first belt transport unit 41 is disposed below the recording unit 5 and transports the sheet S. The second belt transport unit 42 is located downstream of the first belt transport unit 41 in the sheet transport direction and is disposed in the drying unit 6, and transports the sheet S.

[0012] The recording unit 5 is located downstream of the sheet body supply unit 3 in the sheet body conveying direction and is disposed opposite to the first belt conveying unit 41. The recording unit 5 is disposed above the first conveying belt 411 at a predetermined interval, opposite to the sheet body S that is adsorbed and held on the upper surface of the first conveying belt 411 for conveying. That is, the recording unit 5 is opposite to the sheet body S conveyed by the sheet body conveying unit 4.

[0013] like Figure 2 As shown, the recording unit 5 maintains head units 51B, 51C, 51M, and 51Y corresponding to the four colors: black, cyan, magenta, and yellow, respectively. Head units 51B, 51C, 51M, and 51Y are arranged along the sheet transport direction Dc with their long sides parallel to the sheet width direction Dw, wherein the sheet width direction Dw and the sheet transport direction Dc are orthogonal. Furthermore, the four head units 51B, 51C, 51M, and 51Y have the same basic structure; therefore, in the following description, unless specifically defined, the identification marks "B," "C," "M," and "Y" representing each color may be omitted.

[0014] Each color of the head unit 51 has a recording head 52 with a linear inkjet pattern. In each color of the head unit 51, multiple recording heads 52 are arranged in an alternating pattern along the width direction Dw of the sheet body (for example, 3 (52a, 52b, 52c)).

[0015] The recording head 52 has multiple ink ejection nozzles 521 at its bottom. These nozzles are arranged along the width direction Dw of the sheet body, enabling ink to be ejected onto the entire recording area of ​​the sheet body S. In other words, the recording head 52 has multiple ink ejection nozzles 521 that eject ink onto the sheet body S. The recording unit 5 sequentially ejects ink from the recording heads 52 of the four color head units 51B, 51C, 51M, and 51Y onto the sheet body S conveyed by the first conveyor belt 411, recording either a panchromatic image or a black-and-white image onto the sheet body S.

[0016] The drying section 6 is positioned downstream of the recording section 5 in the sheet transport direction and is equipped with a second conveyor belt 42. In the drying section 6, while the sheet S, on which the recording section 5 has recorded an ink image, is held and transported by the second conveyor belt 421, the ink on the recording surface is dried. The dried sheet S is then discharged to the sheet discharge section 21.

[0017] The control unit 7 includes a CPU, a storage unit, and other electronic circuits and components (not shown). Based on the control program and data stored in the storage unit, the CPU controls the operation of each component of the inkjet recording apparatus 1 and performs processing related to the function of the inkjet recording apparatus 1. The sheet supply unit 3, sheet transport unit 4, recording unit 5, and drying unit 6 each receive instructions individually from the control unit 7 and simultaneously record onto the sheet S. The storage unit is, for example, a combination of non-volatile storage devices such as program ROM (Read Only Memory) and data ROM, and volatile storage devices such as RAM (Random Access Memory).

[0018] Next, the structure of the ink supply system surrounding the recording section 5 will be explained. Figure 3 It means Figure 1 This is an explanatory diagram of the structure of the ink supply system and control system surrounding the recording unit 5 of the inkjet recording apparatus 1. The inkjet recording apparatus 1 includes an ink container 11, an ink supply device (liquid delivery device) 12, and a head drive board 53.

[0019] The ink container 11 is detachably mounted relative to the main body 2 of the device. The ink container 11 contains the ink supplied to the auxiliary cartridge 123, which will be described later, for the ink supply device 12. The ink (liquid) in the ink container 11 is transported to the recording head 52 via the auxiliary cartridge 123.

[0020] The ink supply device 12 supplies ink from the ink container 11 to the recording head 52. The ink supply device 12 includes a first flow channel 121, a first pump 122, an auxiliary cartridge 123, and a first leakage detection unit 124.

[0021] The first flow channel 121 extends from the ink container 11 to the recording head 52. That is, the first flow channel 121 is positioned on the ink (liquid) supply side relative to the recording head 52. Ink flows within the first flow channel 121. Midway through the first flow channel 121, a first pump 122 and an auxiliary cartridge 123 are sequentially arranged from the upstream side in the ink delivery direction.

[0022] The first pump 122 is connected to the first flow channel 121 and is positioned downstream of the ink container 11 in the ink delivery direction. The first pump 122 moves the ink within the first flow channel 121. Specifically, the first pump 122 draws ink from the ink container 11 and ejects the ink into the auxiliary cartridge 123. The operation of the first pump 122 is controlled by the control unit 7.

[0023] The auxiliary cartridge 123 stores the ink supplied to the recording head 52. An ink level sensor (not shown) is provided in the auxiliary cartridge 123. The control unit 7 controls the first pump 122, controlling the amount of ink supplied from the ink container 11 to the auxiliary cartridge 123 by controlling the driving time of the first pump 122. If, even after a certain period of time has elapsed since the first pump 122 began driving, the ink level in the auxiliary cartridge 123, detected by the ink level sensor, is not higher than a predetermined value, the control unit 7 determines that the ink container 11 is empty. Furthermore, the ink level in the auxiliary cartridge 123 is managed in a manner that maintains a fixed head difference with the recording head 52.

[0024] The first leakage detection unit 124 includes a liquid receiving dish 124t and a leakage detection sensor 124s.

[0025] The liquid receiving dish 124t is configured to cover the entire lower part of the first flow channel 121, the first pump 122, and the auxiliary box 123, or to cover areas where leakage is possible. The liquid receiving dish 124t, for example, receives ink (liquid) leaking from the connection of the first flow channel 121, the first pump 122 itself, and the auxiliary box 123 itself.

[0026] A leak detection sensor 124s detects ink (liquid) that has fallen into and been stored in a liquid receiving dish 124t. The leak detection sensor 124s has two electrodes 124b that protrude or extend into the liquid receiving dish 124t. If liquid comes into contact with the two electrodes 124b, an electric current flows through the liquid, thereby the leak detection sensor 124s detects leakage in the ink supply system that supplies ink to the recording head 52.

[0027] As described above, the leakage detection sensor 124s detects leakage of ink (liquid) in the first flow channel 121 and the first pump 122. If the leakage detection sensor 124s detects ink (liquid) leakage, it outputs a leakage detection signal to the control unit 7.

[0028] The head drive board 53 is disposed adjacent to the recording head 52 and sends a drive signal to the recording head 52. The recording head 52 has a drive element (not shown) for an ink ejection nozzle 521. The head drive board 53 sends a drive signal having a predetermined drive waveform and drive voltage to the drive element of the ink ejection nozzle 521. The drive waveform of the drive element of the ink ejection nozzle 521 is prepared in advance based on the grayscale value of the pixels (dots) of the image recorded by the ejected ink droplets.

[0029] The control unit 7 can control the head drive substrate 53 to change the ejection speed of the ink ejected from the recording head 52. In this way, the control unit 7 controls the operation of the recording head 52 to record an image onto the thin film S.

[0030] In addition, such as Figure 1 As shown, the inkjet recording device 1 includes a maintenance unit 13. The maintenance unit 13 performs maintenance on the ink ejection surface of the recording head 52, where ink ejection nozzles 521 are arranged. The maintenance unit 13 is supported by a unit moving mechanism 14 and is capable of moving horizontally along the sheet body transport direction. When not performing maintenance on the recording head 52, the maintenance unit 13 can... Figure 1 As shown, it is positioned at the first position below the second belt conveyor section 42.

[0031] In the inkjet recording apparatus 1, maintenance of the recording head 52 is performed at predetermined times. For example, maintenance of the recording head 52 is performed at the start of recording after a long period of inactivity or during an interval of recording operation. When maintenance of the recording head 52 is performed, the control unit 7 moves the maintenance unit 13 to a second position below the recording unit 5 via the unit moving mechanism 14.

[0032] Furthermore, during maintenance of the recording head 52, the first belt conveyor 41, which is positioned opposite the lower surface of the recording section 5, is retracted to a position relative to the lower surface of the recording section 5 using a moving mechanism (not shown). Figure 1 The position shown is closer to the sheet supply section 3, which is located lower down. Then, the maintenance unit 13 moves to a second position below the recording section 5 using the unit moving mechanism 14, approaching the ink ejection surface of the recording head 52.

[0033] Next, the structure of the ink discharge system around the recording section 5 will be explained. Figure 4 It means Figure 1 This is an explanatory diagram of the structure of the ink discharge system and control system surrounding the recording unit 5 of the inkjet recording device 1. The inkjet recording device 1 includes a wiper blade 131 and a waste liquid tray 132 installed in the maintenance unit 13, as well as an ink discharge device (liquid delivery device) 15.

[0034] The scraper 131 is held in a bracket (not shown), with its tip protruding upwards. The scraper 131 is, for example, a rubber product such as EPDM (ethylene propylene diene monomer), and is an elastic member with a tip extending generally in the sheet conveying direction at its upper end. During maintenance of the recording head 52, if the maintenance unit 13 approaches the ink ejection surface 52F of the recording head 52, the scraper 131 contacts the ink ejection surface 52F from below with a predetermined pressure, and moves along the sheet width direction Dw together with the movement of the bracket holding the scraper 131.

[0035] Furthermore, the recording head 52 has a cleaning fluid supply section 54 at one end of the ink ejection surface 52F in the width direction Dw of the sheet body. During maintenance of the recording head 52, cleaning fluid Fc flows out to the lower surface of the cleaning fluid supply section 54. The cleaning fluid Fc is maintained by its surface tension in a state of diffusion throughout the entire area of ​​the lower surface of the cleaning fluid supply section 54.

[0036] Then, ink Fi is ejected from ink ejection nozzle 521 to ink ejection surface 52F. Ink Fi may contain, for example, ink with increased viscosity, foreign matter, air bubbles, etc. within ink ejection nozzle 521, and is forcibly ejected from ink ejection nozzle 521. Ink Fi is maintained in a state of diffusion throughout the entire area under the ink ejection surface 52F due to its surface tension.

[0037] Furthermore, the scraper 131 contacts the lower surface of the cleaning fluid supply section 54 from below with a predetermined pressure. Then, the scraper 131 wipes away the cleaning fluid Fc on the lower surface of the cleaning fluid supply section 54, thereby transporting the cleaning fluid Fc to the ink ejection surface 52F. When the cleaning fluid Fc is transported to the ink ejection surface 52F by the scraper 131, it mixes with the ink Fi held by the ink ejection surface 52F and is wiped away.

[0038] Below the ink ejection surface 52F of the recording head 52, a waste liquid tray 132 is disposed opposite to the ink ejection surface 52F in the vertical direction. The waste liquid tray 132 is formed into a cuboid shape that is rectangular in plan view, extending horizontally along the sheet body transport direction and the sheet body width direction Dw. The waste liquid tray 132 has a recess 132d formed on its upper surface and recessed downward. During maintenance of the recording head 52, the ink Fi and cleaning fluid Fc wiped off from the ink ejection surface 52F by the scraper 131 fall into the recess 132d and are recovered.

[0039] The ink discharge device 15 discharges ink (waste liquid) from the waste liquid tray 132 ejected from the recording head 52. The ink discharge device 15 includes a second flow channel 151, a second pump 152, a waste liquid box 153, and a second leakage detection unit 154.

[0040] The second flow channel 151 extends from the waste liquid tray 132 to the waste liquid container 153. That is, the second flow channel 151 is positioned on the ink (liquid) discharge side relative to the recording head 52. The ink (waste liquid) flows within the second flow channel 151. A second pump 152 is disposed midway through the second flow channel 151.

[0041] The second pump 152 is connected to the second flow channel 151 and is positioned downstream of the waste liquid tray 132 in the ink delivery direction. The second pump 152 causes ink to move within the second flow channel 151. Specifically, the second pump 152 draws ink from the waste liquid tray 132 and ejects the ink into the waste liquid container 153. The operation of the second pump 152 is controlled by the control unit 7.

[0042] The waste liquid container 153 contains ink Fi and cleaning fluid Fc wiped off from the ink ejection surface 52F by the scraper 131, which are recycled into the waste liquid tray 132 during the maintenance of the recording head 52.

[0043] The second leakage detection unit 154 includes a liquid receiving dish 154t and a leakage detection sensor 154s.

[0044] The liquid receiving dish 154t is configured to cover the entire lower part of the second flow channel 151, the second pump 152, and the waste liquid box 153, or to cover areas where leakage is possible. The liquid receiving dish 154t, for example, receives ink (liquid) leaking from the connection of the second flow channel 151, the second pump 152 itself, and the waste liquid box 153 itself.

[0045] The leakage detection sensor 154s detects ink (liquid) that has fallen into and been stored in the liquid receiving dish 154t. The leakage detection sensor 154s has two electrodes 154b that protrude or extend into the liquid receiving dish 154t. If liquid comes into contact with the two electrodes 154b, an electric current flows through the liquid, thereby the leakage detection sensor 154s detects leakage in the ink discharge system from the recording head 52.

[0046] As described above, the leakage detection sensor 154s detects leakage of ink (liquid) in the second flow channel 151 and the second pump 152. If the leakage detection sensor 154s detects ink (liquid) leakage, it outputs a leakage detection signal to the control unit 7.

[0047] Next, the signal transmission in leakage detection will be explained. Figure 5 It means Figure 1 A block diagram of the structure of the inkjet recording device 1 related to leakage detection.

[0048] The control unit 7 includes a leak detection control unit 71 and a pump control unit 72 as its functions. In this embodiment, the various functions of the control unit 7 are implemented by the CPU performing calculations according to the programs related to leak detection and pump control stored in the storage unit.

[0049] Furthermore, the ink supply device 12 includes a first pump power supply circuit 125 and a first latching circuit 126. The ink discharge device 15 includes a second pump power supply circuit 155 and a second latching circuit 156.

[0050] The leakage detection control unit 71 performs various controls related to leakage detection based on leakage detection signals received from the first leakage detection unit 124 (leakage detection sensor 124s) of the ink supply device 12 and the second leakage detection unit 154 (leakage detection sensor 154s) of the ink discharge device 15. For example, the leakage detection control unit 71 sends leakage detection information from the ink supply device 12 and the ink discharge device 15 to the pump control unit 72.

[0051] Furthermore, upon receiving a leak detection signal, the leak detection control unit 71 controls either the first leak detection unit 124 or the second leak detection unit 154. Specifically, upon receiving a leak detection signal, the leak detection control unit 71 disconnects the power supply to either the first leak detection unit 124 or the second leak detection unit 154. Additionally, upon receiving a leak detection signal, the leak detection control unit 71 displays leak detection information on the operation panel 2c located on the upper part of the device body 2 and notifies the user that there is an abnormality in the ink supply system or ink discharge system.

[0052] The pump control unit 72 controls the operation of the first pump 122 and the second pump 152. Specifically, the pump control unit 72 controls the switching on / off of the power supply to the first pump 122 and the second pump 152 via the first pump power supply circuit 125 and the second pump power supply circuit 155. Furthermore, the pump control unit 72 can also control the rotational speed, drive time, and other parameters of the first pump 122 and the second pump 152.

[0053] The first pump power supply circuit 125 and the second pump power supply circuit 155 send control signals related to the power supply of each pump to the first pump 122 and the second pump 152. For example, the first pump power supply circuit 125 sends a power-on signal and a power-off signal to the first pump 122 to turn the power on / off of the first pump 122. Similarly, the second pump power supply circuit 155 sends a power-on signal and a power-off signal to the second pump 152 to turn the power on / off of the second pump 152.

[0054] The first latch circuit 126 and the second latch circuit 156 are self-locking circuits that maintain the input state of the signals. The input side of the first latch circuit 126 is wired to receive the output signals of the first leak detection unit 124 and the second leak detection unit 154, and the output side of the first latch circuit 126 is wired to output a signal to the first pump power supply circuit 125. The input side of the second latch circuit 156 is wired to receive the output signal of the second leak detection unit 154, and the output side of the second latch circuit 156 is wired to output a signal to the second pump power supply circuit 155.

[0055] The first latching circuit 126 receives and holds the leakage detection signals from the first leakage detection unit 124 and the second leakage detection unit 154. Then, the first latching circuit 126 sends the leakage detection signals held by the first leakage detection unit 124 and the second leakage detection unit 154 to the first pump power supply circuit 125. Furthermore, based on the leakage detection signals, the first latching circuit 126 causes the first pump power supply circuit 125 to disconnect the power supply to the first pump 122. That is, the first pump power supply circuit 125 disconnects the power supply to the first pump 122 upon receiving the leakage detection signals from the first leaking detection unit 124 and the second leakage detection unit 154 from the first latching circuit 126.

[0056] The second latching circuit 156 receives and holds the leakage detection signal from the second leakage detection unit 154. Then, the second latching circuit 156 sends the leakage detection signal held by the second leakage detection unit 154 to the second pump power supply circuit 155. Furthermore, based on the leakage detection signal, the second latching circuit 156 causes the second pump power supply circuit 155 to disconnect the power supply to the second pump 152. That is, the second pump power supply circuit 155 disconnects the power supply to the second pump 152 upon receiving the leakage detection signal from the second leakage detection unit 154 from the second latching circuit 156.

[0057] According to the above structure, upon detecting ink (liquid) leakage, the first latching circuit 126 and the second latching circuit 156, which receive the leakage detection signal, disconnect the power supply to the first pump 122 and the second pump 152 via the first pump power supply circuit 125 and the second pump power supply circuit 155. That is, even if an adverse situation occurs in the first leakage detection unit 124 or the second leakage detection unit 154 due to the leakage after it is detected, and the detection state is deactivated, the initially detected leakage state is maintained by the first latching circuit 126 and the second latching circuit 156. Therefore, the restart of the first pump 122 and the second pump 152 can be stopped, and the restart of ink delivery can be prevented. Thus, in the event of leakage detection, ink delivery can be appropriately stopped.

[0058] Furthermore, upon receiving a leak detection signal, the control unit 7 disconnects the power supply to either the first leak detection unit 124 or the second leak detection unit 154. According to this structure, the power supply to the first leak detection unit 124 and the second leak detection unit 154 is immediately disconnected after a leak occurs. That is, if the first leak detection unit 124 and the second leak detection unit 154 are kept energized after a leak occurs, impurities will continue to accumulate on the electrodes 124b and 154b, potentially causing adverse effects on the sensors. However, this structure can suppress such adverse effects. Therefore, damage to the leak detection sensors 124s and 154s can be prevented.

[0059] Furthermore, the inkjet recording apparatus 1 includes an ink supply device 12 for supplying ink to the recording head 52 and an ink discharge device 15 for discharging ink from the recording head 52 as liquid transport devices. According to this structure, in both the ink supply system supplying ink to the recording head 52 and the ink discharge system discharging ink from the recording head 52, the detected leakage state can be maintained separately, and the restart of the pump can be prevented. Therefore, the location of the ink leakage can be clearly identified, and the parts requiring maintenance can be easily determined.

[0060] Next, an example of the leakage detection process in the inkjet recording device 1 will be described. Figure 6 It means Figure 1 A flowchart of an example of leakage detection processing in inkjet recording device 1.

[0061] If the inkjet recording device 1 is powered on ( Figure 6 If the "start" is not specified, then in step S101, the control unit 7 turns on the power of the leakage detection sensor 124s of the first leakage detection unit 124, detects leakage in the ink supply system that supplies ink to the recording head 52, and proceeds to step S102.

[0062] In step S102, the control unit 7 determines whether there is any leakage in the ink supply system that supplies ink to the recording head 52. If there is no leakage (yes in step S102), the control unit 7 proceeds to step S103 and turns on the power to the first pump 122.

[0063] In step S104, the control unit 7 turns on the power supply of the leakage detection sensor 154s of the second leakage detection unit 154, detects leakage in the ink discharge system from the recording head 52, and proceeds to step S105.

[0064] In step S105, the control unit 7 determines whether there is any leakage in the ink ejection system from the recording head 52. If there is no leakage (Yes in step S105), the control unit 7 proceeds to step S106 and turns on the power to the second pump 152. Then, the control unit 7 normally ends the processing related to leakage detection. Figure 6 (The "normal ending").

[0065] Furthermore, if there is leakage in the ink supply system that supplies ink to the recording head 52 (No in step S102), the control unit 7 proceeds to step S109.

[0066] In step S109, the control unit 7 disconnects the power supply to the first pump 122, disconnects the power supply to the second pump 152, disconnects the power supply to the leakage detection sensor 124s of the first leakage detection unit 124, and then proceeds to step S110.

[0067] In step S110, the control unit 7 turns on the power supply of the leakage detection sensor 154s of the second leakage detection unit 154, detects leakage in the ink discharge system from the recording head 52, and then proceeds to step S111.

[0068] In step S111, the control unit 7 determines whether there is any leakage in the ink discharge system from the recording head 52. If there is no leakage (Yes in step S111), the control unit 7 proceeds to step S112, displays the leakage detection information on the operation panel 2c located on the upper part of the device body 2, and notifies the user that there is an abnormality in the ink supply system. Then, the control unit 7 stores the abnormality in the processing related to the leakage detection and ends the processing. Figure 6 (abnormal termination).

[0069] Furthermore, if there is leakage in the ink discharge system from the recording head 52 (No in step S111), the control unit 7 proceeds to step S113, disconnects the power supply to the leakage detection sensor 154s of the second leakage detection unit 154, and proceeds to step S114.

[0070] In step S114, the control unit 7 displays the leakage detection information on the operation panel 2c located on the upper part of the device body 2, notifying the user that there are abnormalities in both the ink supply system and the ink discharge system. Then, the control unit 7 stores the information regarding the abnormality in the leakage detection process and terminates the process. Figure 6 (abnormal termination).

[0071] in addition, Figure 6 The leakage detection process shown is repeatedly performed during the operation of the inkjet recording device 1.

[0072] Based on the above structure, in addition to maintaining the leakage detection signal through hardware such as the first latch circuit 126 and the second latch circuit 156, and sending the leakage detection signal to the first pump power supply circuit 125 and the second pump power supply circuit 155, the driving of the first pump 122 and the second pump 152 can also be controlled by the software of the control unit 7. Therefore, in the event of leakage, the ink delivery can be appropriately stopped.

[0073] The embodiments of the present invention have been described above, but the scope of the present invention is not limited thereto.

[0074] For example, in the above embodiment, the inkjet recording apparatus 1 includes an ink supply device 12 and an ink discharge device 15 as a liquid delivery device for leak detection, but it is not limited to this structure. The inkjet recording apparatus 1 may also be configured to include either the ink supply device 12 or the ink discharge device 15, and may further include a liquid delivery device for leak detection.

Claims

1. A liquid conveying device, wherein, The liquid conveying device includes: Flow channels allow for the flow of liquids; A pump, connected to the flow channel, moves the liquid within the flow channel; The leakage detection unit detects leakage of the liquid in the flow channel and the pump, and outputs a leakage detection signal; The pump power supply circuit is used to connect / disconnect the power supply to the pump. as well as A latching circuit receives and holds the leakage detection signal, and sends the leakage detection signal to the pump power supply circuit to disconnect the power supply to the pump.

2. The liquid conveying device according to claim 1, wherein, The liquid delivery device includes a control unit for controlling the leakage detection unit. Upon receiving the leakage detection signal, the control unit disconnects the power supply to the leakage detection unit.

3. The liquid conveying device according to claim 2, wherein, The flow channel includes: A first flow channel is disposed on the supply side of the liquid; and The second flow channel is located on the liquid discharge side. The liquid delivery device has: A first pump moves the liquid within the first flow channel; The first leakage detection unit detects leakage of the liquid in the first flow channel and the first pump, and outputs a leakage detection signal; The second pump moves the liquid within the second flow channel; as well as The second leakage detection unit detects leakage of the liquid in the second flow channel and the second pump, and outputs a leakage detection signal. The control unit sequentially detects whether it receives leakage detection signals from the first leakage detection unit and the second leakage detection unit. Upon receiving the leakage detection signal from the first leakage detection unit, the power supply to the first pump and the power supply to the second pump are disconnected. Upon receiving the leakage detection signal from the second leakage detection unit, the power supply to the second pump is disconnected.

4. An inkjet recording device, wherein, The inkjet recording device includes: The recording head ejects ink onto the recording medium; and The liquid delivery device according to claim 1 or 2 supplies the ink as the liquid to the recording head.

5. An inkjet recording device, wherein, The inkjet recording device includes: The recording head ejects ink onto the recording medium; and The liquid delivery device of claim 3 supplies the ink as the liquid to the recording head and discharges the ink ejected from the recording head. The liquid delivery device includes: An ink supply device, comprising a first flow channel, a first pump, and a first leakage detection unit, supplies ink to the recording head; and An ink discharge device, comprising a second flow channel, a second pump, and a second leakage detection unit, discharges the ink from the recording head.

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