Liquid supply apparatus and ink jet recording apparatus

Abstract

The invention provides a liquid supply apparatus and an ink jet recording apparatus. The liquid supply device includes a diaphragm pump, a suction unit, a discharge unit, and an optional unit. The suction unit and the discharge unit sandwich at least one of the optional units therebetween, and are disposed so as to overlap each other such that the inflow chamber of the suction unit and the outflow chamber of the discharge unit continuously face the diaphragm on one side in the reciprocating direction of the diaphragm. The suction unit, the ejection unit, and the selectable unit are detachable from each other.

Description

Technical Field

[0001] The present invention relates to a liquid supply device and an inkjet recording device. Background Art

[0002] As a recording device such as a printer or a copier, an inkjet recording device that records an image by ejecting ink onto a recording medium such as paper is widely used because it can record high-definition images. In such an inkjet recording device, the ink is transported by a pump from an ink container containing the ink to a recording head that ejects the ink onto the recording medium. As such a pump, a diaphragm pump is known. Summary of the invention

[0003] An object of the present invention is to provide a liquid supply device and an inkjet recording device, which can suppress the deterioration of the quality of the liquid discharged from a diaphragm pump or achieve the improvement of the quality of the liquid.

[0004] The liquid supply device of the first structure of the present invention comprises a diaphragm pump, a suction unit, a discharge unit and an optional unit. The diaphragm pump transports liquid by the reciprocating movement of the diaphragm. The suction unit has a suction check valve that allows the liquid to flow relative to the diaphragm only in the suction direction and an inflow chamber for the liquid to flow in through the suction check valve. The discharge unit has a discharge check valve that allows the liquid to flow relative to the diaphragm only in the discharge direction and an outflow chamber for the liquid flowing in from the inflow chamber to flow out toward the discharge check valve. The optional unit is arranged between the suction unit and the discharge unit. The suction unit and the discharge unit sandwich at least one of the optional units, and are arranged in an overlapping manner so that the inflow chamber and the outflow chamber are opposite to the diaphragm on one side of the reciprocating direction of the diaphragm. The suction unit, the discharge unit and the optional unit can be installed and removed from each other.

[0005] According to the first structure of the present invention, an optional unit is arranged on the upstream side of the liquid flow direction of the ejection unit located on the liquid ejection side relative to the diaphragm. The optional unit can be set as a structure that performs various treatments on the circulating liquid. Therefore, for the liquid ejected from the diaphragm pump, it is possible to suppress the low quality of the liquid or achieve high quality of the liquid. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 It is a schematic cross-sectional front view of an inkjet recording device according to one embodiment of the present invention. Figure 2 yes Figure 1 A plan view of the periphery of a recording unit of an inkjet recording device. Figure 3 Yes means Figure 1 An explanatory diagram of the structure of a control system and an ink supply system around a recording unit of an inkjet recording device. Figure 4 yes Figure 3 Front view of the ink supply device. Figure 5 yes Figure 3 A top view of an ink supply device. Figure 6 yes Figure 3 A side view of an ink supply device. Figure 7 yes Figure 3 A three-dimensional view of an ink supply device. Figure 8 yes Figure 6 A vertical sectional side view of an ink supply device. Fig. 9 yes Figure 8 The present invention is a vertical sectional side view of the ink supply device, and is a diagram showing a state in which the constituent elements are disassembled. Fig.10 yes Figure 8 A vertical sectional side view of an ejection unit of an ink supply device. Fig.11 yes Figure 8 A vertical sectional side view of the suction unit of the ink supply device. Fig.12 yes Figure 8 A vertical sectional side view of a filter unit of an ink supply device. Fig.13 yes Fig.12 Top view of the filter unit. Fig.14 yes Fig.12 1 is a top view of the filter unit, and is a diagram showing a state in which the filter is removed. Fig.15 It is a top view of the optional unit of modification example 1. Fig.16 It is a top view of the optional unit of modification example 2. Fig.17 yes Figure 6 A stereoscopic view of a plate-like component of an ink supply device. DETAILED DESCRIPTION

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

[0008] Figure 1 It is a schematic cross-sectional front view of the inkjet recording device 1 according to the embodiment. Figure 2 yes Figure 1 1 is a plan view of the vicinity of a recording unit 5 of an inkjet recording device 1. The inkjet recording device 1 is, for example, an inkjet recording printer. Figure 1and Figure 2 As shown, the inkjet recording apparatus 1 includes an apparatus main body 2 , a paper supply unit 3 , a paper conveying unit 4 , a recording unit 5 , a drying unit 6 , a paper discharge unit 7 , and a control unit 8 .

[0009] The paper supply unit 3 is disposed, for example, at the lower portion of the apparatus body 2. The paper supply unit 3 stores a plurality of sheets of paper (recording media) S, and separates and feeds the sheets of paper S one by one during recording.

[0010] The paper conveying unit 4 is arranged on the downstream side of the paper conveying direction of the paper supply unit 3, and conveys the paper S fed from the paper supply unit 3. The paper conveying unit 4 conveys the paper S to the recording unit 5 and the drying unit 6, and discharges the recorded and dried paper S to the paper discharge unit 7. The paper conveying unit 4 has, for example, a reversing conveying unit 4r. In the case of double-sided recording, the paper conveying unit 4 distributes the paper S after recording and drying on the first side to the reversing conveying unit 4r, switches the conveying direction, and conveys the paper S after reversing the front and back sides again to the recording unit 5 and the drying unit 6.

[0011] The paper conveying section 4 includes a first belt conveying section 41 and a second belt conveying section 42. The first belt conveying section 41 includes a first conveying belt 411 formed in an endless shape. The second belt conveying section 42 includes a second conveying belt 421 formed in an endless shape. The first belt conveying section 41 and the second belt conveying section 42 adsorb and hold the paper S on the outer surface (upper surface) of the upper side of each of the first conveying belt 411 and the second conveying belt 421 for conveying. The first belt conveying section 41 is arranged below the recording section 5 and conveys the paper S. The second belt conveying section 42 is located on the downstream side of the paper conveying direction relative to the first belt conveying section 41 and is arranged in the drying section 6 and conveys the paper S.

[0012] The recording unit 5 is located on the downstream side of the paper feeding unit 3 in the paper conveying direction, and is arranged opposite to the first belt conveying unit 41. The recording unit 5 is arranged opposite to the paper S that is sucked and held on the upper surface of the first conveying belt 411 for conveying, and is arranged above the first conveying belt 411 with a predetermined interval. That is, the recording unit 5 is opposite to the paper S conveyed by the paper conveying unit 4.

[0013] like Figure 2 As shown, the recording unit 5 holds head units 51B, 51C, 51M, and 51Y corresponding to four colors of black, cyan, magenta, and yellow, respectively. The head units 51B, 51C, 51M, and 51Y are arranged along the paper conveying direction Dc in such a manner that the long side direction is parallel to the paper width direction Dw, and the paper width direction Dw is orthogonal to the paper conveying direction Dc. In addition, the basic structure of the four head units 51B, 51C, 51M, and 51Y is the same, so in the following description, the identification marks "B", "C", "M", and "Y" representing various colors are sometimes omitted except for cases that require special limitation.

[0014] Each color head unit 51 includes a line inkjet recording head 52. In each color head unit 51, a plurality of recording heads 52 (eg, three (52a, 52b, 52c)) are arranged in a staggered pattern along the paper width direction Dw.

[0015] The recording head 52 has a plurality of ink ejection nozzles 521 at the bottom. The plurality of ink ejection nozzles 521 are arranged in a row along the paper width direction Dw, and can eject ink to the entire recording area on the paper S. That is, the recording head 52 has a plurality of ink ejection nozzles 521 that eject ink onto the paper S. The recording unit 5 ejects ink from the respective recording heads 52 of the four color head units 51B, 51C, 51M, and 51Y in sequence toward the paper S transported by the first transport belt 411, and records a full-color image or a black-and-white image on the paper S.

[0016] The drying section 6 is arranged on the downstream side of the recording section 5 in the paper conveying direction, and is provided with a second belt conveying section 42. In the drying section 6, the ink is dried while the paper S on which the ink image is recorded by the recording section 5 is held by suction on the second conveying belt 421 for conveyance. The dried paper S is discharged to the paper discharge section 7.

[0017] The control unit 8 includes a CPU, a storage unit, and other electronic circuits and electronic components (all not shown). The CPU controls the operation of each component provided in the inkjet recording device 1 according to the control program and data stored in the storage unit, and performs processing related to the function of the inkjet recording device 1. The paper supply unit 3, the paper conveying unit 4, the recording unit 5, and the drying unit 6 receive instructions from the control unit 8 separately, and record on the paper S in a linked manner. The storage unit is composed of a combination of a non-volatile storage device such as a program ROM (Read Only Memory) and a data ROM, and a volatile storage device such as a RAM (Random Access Memory).

[0018] Next, use Figure 3 The structure around the recording unit 5 will be described. Figure 3 Yes means Figure 1 1 and 2. The inkjet recording device 1 is an explanatory diagram of the structure of a control system and an ink supply system around a recording unit 5 of the inkjet recording device 1. The inkjet recording device 1 includes an ink container 10, an ink supply device (liquid supply device) 20, an auxiliary cartridge 30, and a head driving substrate 53.

[0019] The ink container 10 is detachably provided in the apparatus main body 2. The ink container 10 stores ink to be supplied to the auxiliary cartridge 30. The ink (liquid) in the ink container 10 is transported to the recording head 52 via the auxiliary cartridge 30.

[0020] The ink supply device 20 is arranged on the downstream side of the ink delivery direction relative to the ink container 10. The ink supply device 20 includes a diaphragm pump 21, which sucks the ink in the ink container 10 and ejects the ink toward the auxiliary box 30. The operation of the diaphragm pump 21 is controlled by the control unit 8. The detailed structure of the ink supply device 20 will be described later.

[0021] The auxiliary cartridge 30 stores ink to be supplied to the recording head 52. An ink level sensor (not shown) is provided in the auxiliary cartridge 30. The control unit 8 controls the diaphragm pump 21, and controls the supply amount of ink supplied from the ink container 10 to the auxiliary cartridge 30 by the driving time of the diaphragm pump 21. When the ink level in the auxiliary cartridge 30 detected by the ink level sensor is not higher than a predetermined value even after a certain period of time has passed since the driving time of the diaphragm pump 21, the control unit 8 determines that the ink level in the ink container 10 is empty. In addition, the ink level of the auxiliary cartridge 30 is managed in such a way that the head difference with the recording head 52 is fixed.

[0022] The head driving substrate 53 is arranged adjacent to the recording head 52, and sends a driving signal to the recording head 52. The recording head 52 has a driving element (not shown) for the ink ejection nozzle 521. The head driving substrate 53 sends a driving signal having a predetermined driving waveform and driving voltage to the driving element of the ink ejection nozzle 521. The driving waveform of the driving element of the ink ejection nozzle 521 is prepared in advance according to the grayscale value of the pixel (dot) of the image recorded by the ejected ink droplets. The control unit 8 can control the head driving substrate 53 to change the ejection speed of the ink ejected from the recording head 52. In this way, the control unit 8 controls the operation of the recording head 52 to record the image on the paper S.

[0023] Next, use Figures 4 to 8 The outline of the structure of the ink supply device (liquid supply device) 20 will be described. Figure 4 , Figure 5 , Figure 6 and Figure 7 yes Figure 3 The front view, top view, side view and stereoscopic view of the ink supply device 20. Figure 8 yes Figure 6 A vertical sectional side view of the ink supply device 20.

[0024] In the following figures, arrow lines indicating the radial direction Dr of the motor 211 (output shaft 211x) corresponding to the reciprocating direction of the diaphragm 213 described later are appropriately drawn. In the suction unit 22, the discharge unit 23, and the filter units (optional units) 24A and 24B, the direction away from the diaphragm 213 along the radial direction Dr ( Figure 8Specifically, with respect to the suction unit 22, the ejection unit 23 and the filter units (optional units) 24A and 24B, Figure 8 The lower side in the ink flow direction is the upstream side. Figure 8 The upper side in the figure is the downstream side in the ink flow direction.

[0025] The ink supply device 20 includes a diaphragm pump 21 , a suction unit 22 , a discharge unit 23 , and filter units (optional units) 24A and 24B.

[0026] The diaphragm pump 21 includes a motor 211 and a diaphragm mechanism 212. The diaphragm mechanism 212 accommodates a diaphragm 213. The diaphragm pump 21 reciprocates the diaphragm 213 by the motor 211, and transports ink (liquid) by the reciprocating movement of the diaphragm 213.

[0027] The suction unit 22 is connected to the diaphragm mechanism portion 212 of the diaphragm pump 21 in a manner adjacent to the diaphragm 213. The suction unit 22 includes an inflow chamber 222 and a suction check valve 223 provided in the suction housing 221. The inflow chamber 222 is communicated with the interior of the diaphragm mechanism portion 212. Ink is caused to flow from the outside into the inflow chamber 222 through the suction check valve 223. The suction check valve 223 allows ink to flow relative to the diaphragm 213 only in the suction direction, that is, the direction of flowing from the outside into the inflow chamber 222.

[0028] The discharge unit 23 is connected to the suction unit 22. In other words, the discharge unit 23 is arranged with respect to the diaphragm mechanism portion 212 of the diaphragm pump 21 via the suction unit 22 and the filter units 24A and 24B. The discharge unit 23 includes an outflow chamber 232 and a discharge check valve 233 provided in a discharge housing 231. The outflow chamber 232 is connected to the inflow chamber 222 through the filter units 24A and 24B. The outflow chamber 232 allows the ink flowing in from the inflow chamber 222 to flow out toward the discharge check valve 233. The discharge check valve 233 allows the ink to flow relative to the diaphragm 213 only in the discharge direction, that is, the direction of outflow from the outflow chamber 232 to the outside.

[0029] The filter units 24A and 24B are arranged between the suction unit 22 and the ejection unit 23 in the radial direction Dr (the reciprocating direction of the diaphragm 213) of the output shaft 211x of the motor 211. The filter units 24A and 24B respectively have filters 241A and 241B covering the flow cross section of the ink. The filter units 24A and 24B remove foreign matter contained in the ink flowing from the suction unit 22 to the ejection unit 23 through the filters 241A and 241B.

[0030] Next, use Figures 9 to 12 The detailed structure of the ink supply device 20 will be described. Fig. 9 yes Figure 81 is a vertical sectional side view of the ink supply device 20, and is a diagram showing a state in which the constituent elements are disassembled. Fig.10 yes Figure 8 2 is a vertical sectional side view of the ejection unit 23 of the ink supply device 20. Fig.11 yes Figure 8 2 is a vertical sectional side view of the suction unit 22 of the ink supply device 20. Fig.12 yes Figure 8 A vertical cross-sectional side view of the filter unit 24 of the ink supply device 20. Fig.12 In FIG. 1 , identification symbols “A” and “B” of the filter unit 24 are omitted.

[0031] The diaphragm mechanism 212 of the diaphragm pump 21 is connected to a portion of the output shaft 211x of the motor 211 that protrudes. The diaphragm mechanism 212 includes an eccentric cam 214 and a connecting member 215 in addition to the diaphragm 213.

[0032] The eccentric cam 214 is fixed to the output shaft 211x of the motor 211. The eccentric cam 214 is formed into a circle extending outward in the radial direction Dr when viewed from the axial direction of the output shaft 211x, for example. The eccentric cam 214 is fixed to the output shaft 211x at a position eccentric from the center of the radial direction Dr relative to the outer periphery of the circle. The motor 211 rotates the eccentric cam 214 around the axis of the output shaft 211x.

[0033] The connecting member 215 extends toward the diaphragm 213 from the outside in the radial direction Dr of the output shaft 211x. The connecting member 215 is connected to the eccentric cam 214 and the diaphragm 213. A hole 215h is formed at one end of the connecting member 215, through which the outer peripheral portion of the eccentric cam 214 passes in the axial direction of the output shaft 211x. The hole 215h of the connecting member 215 is connected to the outer peripheral portion of the eccentric cam 214 in a manner that allows smooth sliding. When the eccentric cam 214 is rotated by the motor 211, the connecting member 215 moves back and forth along the radial direction Dr of the output shaft 211x.

[0034] In addition, the diaphragm mechanism portion 212 has a diaphragm housing portion 216. The diaphragm housing portion 216 is located outside the connecting member 215 in the radial direction Dr of the output shaft 211x. The diaphragm housing portion 216 is formed into a rectangular cuboid shape when viewed from the radial direction Dr of the output shaft 211x. The diaphragm housing portion 216 is open on one side facing the suction unit 22 and the discharge unit 23.

[0035] The diaphragm housing portion 216 houses the diaphragm 213. The diaphragm 213 is fixed inside the diaphragm housing portion 216. The diaphragm 213 is arranged to face the suction unit 22 and the discharge unit 23 through the opening of the diaphragm housing portion 216.

[0036] The diaphragm 213 is an elastically deformable sheet-like member. The diaphragm 213 is formed, for example, in a circular shape extending in a direction orthogonal to the radial direction Dr of the output shaft 211x. The outer periphery of the diaphragm 213 is fixed to the diaphragm housing portion 216. An eccentric cam 214 is connected to one end of the connecting member 215, and the other end of the connecting member 215 on the opposite side of the one end is connected to the center of the diaphragm 213.

[0037] When the eccentric cam 214 is rotated by the motor 211, the diaphragm 213 reciprocates along the radial direction Dr of the output shaft 211x via the connecting member 215. As a result, the volume of the inflow chamber 222 of the suction unit 22 and the outflow chamber 232 of the discharge unit 23 increases or decreases. The diaphragm pump 21 delivers ink by the reciprocating movement of the diaphragm 213.

[0038] The suction unit 22 is connected to the diaphragm housing portion 216 so as to be adjacent to the diaphragm 213. The suction unit 22 includes a suction case 221, an inflow chamber 222, and a suction check valve 223.

[0039] The suction box 221 is formed in a rectangular parallelepiped shape when viewed from the radial direction Dr of the output shaft 211x of the motor 211. The size and shape of the outer shape (rectangular) of the suction box 221 when viewed from the radial direction Dr are the same as the size and shape of the outer shape (rectangular) of the diaphragm housing portion 216 when viewed from the radial direction Dr. The suction box 221 is connected to the diaphragm housing portion 216 in a sealed state to seal the ink inside.

[0040] The inflow chamber 222 is formed as the internal space of the suction box 221. The inflow chamber 222 is formed in a cylindrical shape extending along the radial direction Dr of the output shaft 211x. The inflow chamber 222 is opened on one side of each of the one end and the other end in the radial direction Dr of the output shaft 211x, and has openings 222a and 222b. The inflow chamber 222 is connected to the diaphragm accommodating portion 216 through the opening 222a, and is opposite to the diaphragm 213. In addition, the inflow chamber 222 is connected to the filter unit 24A through the opening 222b. The ink is allowed to flow into the inflow chamber 222 from the outside through the suction check valve 223.

[0041] Furthermore, a filter 225 , an inner cylinder portion 2222 , a partition wall 2223 , a filter holding portion 2224 , a filter facing portion 2225 , a plurality of flow holes 2226 , and a plurality of protrusions 2227 are provided in the inflow chamber 222 .

[0042] The inner cylinder 2222 is arranged at the radial inner side and the radial center of the inflow chamber 222. In addition, the inner cylinder 2222 is arranged in the inflow chamber 222 at the downstream side of the ink circulation direction relative to the arrangement position of the suction check valve 223. The inner cylinder 2222 is formed into a cylindrical shape extending along the radial direction Dr (the reciprocating direction of the diaphragm 213) of the output shaft 211x of the motor 211. The ink circulates in the inner cylinder 2222 along the radial direction Dr.

[0043] The partition wall 2223 is arranged at the upstream portion of the ink flow direction of the inner cylinder 2222. The partition wall 2223 is formed into a circular flat plate shape that expands in a flange shape toward the outside of the inner cylinder 2222 in a direction orthogonal to the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213). The inner edge of the partition wall 2223 is connected to the upstream portion of the ink flow direction of the outer peripheral surface of the inner cylinder 2222. The outer edge of the partition wall 2223 is connected to the inner peripheral surface of the inflow chamber 222.

[0044] The filter holding portion 2224 is formed at the downstream end of the inner cylinder portion 2222 in the direction of ink circulation. The filter holding portion 2224 is configured as an annular plane facing the downstream side of the direction of ink circulation. The outer periphery of the ink circulation path of the filter 225 is attached to the filter holding portion 2224. Thus, the filter holding portion 2224 holds the outer periphery of the ink circulation path of the filter 225.

[0045] The filter-opposing portion 2225 is located inside the inner cylinder 2222, further inside the ink flow path than the filter holding portion 2224. The filter-opposing portion 2225 is arranged separately from the filter 225 on the upstream side relative to the downstream end of the inner cylinder 2222 in the ink flow direction. The filter-opposing portion 2225 is formed into a circular flat plate shape extending along the ink flow cross section in a direction orthogonal to the radial direction Dr (the reciprocating direction of the diaphragm 213) of the output shaft 211x. The filter-opposing portion 2225 is opposite to the filter 225 in the ink flow direction.

[0046] A plurality of flow holes 2226 are formed in the filter opposing portion 2225. The plurality of flow holes 2226 are arranged at predetermined positions in a direction orthogonal to the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213). The plurality of flow holes 2226 penetrate the filter opposing portion 2225 along the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213). The plurality of flow holes 2226 allow ink to circulate. That is, for example, ink that flows into the inflow chamber 222 through the suction check valve 223 flows toward the filter 225 through the plurality of flow holes 2226.

[0047] A plurality of protrusions 2227 are formed on the filter-opposing portion 2225. Specifically, the plurality of protrusions 2227 are formed on the opposing surface of the filter-opposing portion 2225 that is opposed to the filter 225 in the ink circulation direction. The plurality of protrusions 2227 are arranged at predetermined positions in a direction orthogonal to the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213). The plurality of protrusions 2227 protrude toward the filter 225 in the ink circulation direction along the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213). The protruding length of the protrusion 2227 is preferably a length that just contacts the filter 225, but may be shorter than the length that contacts the filter 225.

[0048] The suction check valve 223 is mounted on the suction housing 221. The suction check valve 223 is a ball check valve whose valve element is a ball. The suction check valve 223 includes a suction portion 2231, a valve element accommodating portion 2232, a liquid guide tube 2233, a sealing member 2234, a valve element 2235, and a biasing member 2236.

[0049] The suction unit 2231 protrudes toward the outside of the suction box 221. The suction unit 2231 is formed in a cylindrical shape and is connected to a liquid delivery pipe (not shown) for delivering ink. The suction unit 22 is connected to the ink container 10 (see Figure 3 )connect.

[0050] The valve core housing portion 2232 is continuously arranged with the suction portion 2231 on the downstream side of the ink flow direction of the suction portion 2231. The liquid guide tube 2233 is continuously arranged with the valve core housing portion 2232 on the downstream side of the ink flow direction of the valve core housing portion 2232. The valve core housing portion 2232 and the liquid guide tube 2233 are formed into a cylindrical shape extending in the ink flow direction. The liquid guide tube 2233 is connected to the inflow chamber 222.

[0051] The valve element housing portion 2232 houses a sealing member 2234 , a valve element 2235 , and a biasing member 2236 .

[0052] The sealing member 2234 is arranged adjacent to the inner peripheral wall of the valve core housing portion 2232 on the upstream side (the suction portion 2231 side) of the valve core 2235 in the ink circulation direction. The sealing member 2234 is, for example, an O-ring made of an elastic body such as rubber, and its outer peripheral portion is closely fitted to the inner peripheral wall of the valve core housing portion 2232. The outer diameter of the sealing member 2234 is larger than the inner diameter of the suction portion 2231. The inner diameter of the sealing member 2234 is smaller than the outer diameter of the valve core 2235.

[0053] The valve core 2235 is composed of a ball (spherical shape) and can move in the valve core housing portion 2232 along the ink flow direction. If the valve core 2235 moves to the upstream side of the ink flow direction, it contacts the inner peripheral portion of the sealing member 2234 and closes the suction portion 2231. Thus, the suction check valve 223 allows the ink to flow relative to the diaphragm 213 only in the suction direction, preventing the backflow of the ink.

[0054] The urging member 2236 is disposed on the downstream side (on the liquid guide tube 2233 side) in the ink flow direction of the valve body 2235. The urging member 2236 is composed of, for example, a compression coil spring, and the axis of the coil extends along the central axis of the valve body housing portion 2232.

[0055] The upstream end of the force member 2236 in the ink flow direction contacts the valve core 2235 which is a ball. The downstream end of the force member 2236 in the ink flow direction contacts the wall surface of the valve core housing 2232 at the downstream end in the ink flow direction opposite to the valve core 2235. Thus, the force member 2236 applies force to the valve core 2235 in the direction of contact with the sealing member 2234, that is, in the upstream side of the ink flow direction. The suction check valve 223 prevents the backflow of ink by making the valve core 2235 contact with the inner peripheral portion of the sealing member 2234 through the force member 2236, so that the ink flows only in the suction direction relative to the diaphragm 213.

[0056] In addition, when the diaphragm pump 21 is operated, the valve core 2235 overcomes the force of the biasing member 2236 by its suction force and moves to the downstream side of the ink flow direction, and the ink flows from the outside of the suction unit 22 through the suction check valve 223 into the inflow chamber 222. When the diaphragm pump 21 is stopped, the valve core 2235 moves to the upstream side of the ink flow direction by the force of the biasing member 2236 and contacts the sealing member 2234, thereby preventing the backflow of the ink.

[0057] The discharge unit 23 is connected to the filter unit 24B. As described above, the discharge unit 23 includes the discharge box 231, the outflow chamber 232, and the discharge check valve 233.

[0058] The ejection box 231 is formed into a substantially rectangular parallelepiped shape when viewed from the radial direction Dr of the output shaft 211x of the motor 211. The size and shape of the outer shape (rectangular) of the ejection box 231 when viewed from the radial direction Dr are the same as the size and shape of the outer shape (rectangular) of the diaphragm housing 216, the suction box 221, and the filter units 24A and 24B when viewed from the radial direction Dr. The ejection box 231 is connected to a filter housing 242B of the filter unit 24B described later in a sealed state in which ink is sealed inside.

[0059] The outflow chamber 232 is formed as the internal space of the ejection box 231. The outflow chamber 232 is formed in a cylindrical shape extending along the radial direction Dr of the output shaft 211x. The outflow chamber 232 is opened on one side of one end portion in the radial direction Dr of the output shaft 211x, and an opening portion 232a is formed. The outflow chamber 232 is connected to the filter unit 24B through the opening portion 232a. The ink flowing in from the inflow chamber 222 of the suction unit 22 flows out from the outflow chamber 232 toward the ejection check valve 233 through the filter unit 24B.

[0060] In addition, a plurality of protrusions 2327 are provided in the outflow chamber 232. The plurality of protrusions 2327 are arranged in the outflow chamber 232 at the upstream side of the ink circulation direction relative to the arrangement position of the ejection check valve 233. Specifically, the plurality of protrusions 2327 are formed on the end wall facing the upstream side of the ink circulation direction in the outflow chamber 232. The plurality of protrusions 2327 are arranged at predetermined positions in a direction orthogonal to the radial direction Dr (the reciprocating direction of the diaphragm 213) of the output shaft 211x.

[0061] The plurality of protrusions 2327 protrude toward the upstream side of the ink circulation direction along the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213). Specifically, the plurality of protrusions 2327 protrude toward the upstream side of the ink circulation direction toward the filter 241 provided in the filter unit 24 adjacent to the radial direction Dr of the output shaft 211x. The protruding length of the protrusion 2327 is preferably the length just in contact with the filter 241, but may be shorter than the length in contact with the filter 241.

[0062] The discharge check valve 233 is mounted on the discharge box 231. The discharge check valve 233 is a ball check valve whose valve element is a ball. The discharge check valve 233 includes a discharge portion 2331, a valve element accommodating portion 2332, a liquid guide tube 2333, a sealing member 2334, a valve element 2335, and a biasing member 2336.

[0063] The ejection unit 2331 protrudes toward the outside of the ejection box 231. The ejection unit 2331 is formed in a cylindrical shape and is connected to a liquid delivery pipe (not shown) for delivering ink. The ejection unit 23 is connected to the auxiliary box 30 (see Figure 3 )connect.

[0064] The valve core housing portion 2332 is continuously arranged with the ejection portion 2331 on the upstream side of the ink flow direction of the ejection portion 2331. The liquid guide tube 2333 is continuously arranged with the valve core housing portion 2332 on the upstream side of the ink flow direction of the valve core housing portion 2332. The valve core housing portion 2332 and the liquid guide tube 2333 are formed into a cylindrical shape extending in the ink flow direction. The liquid guide tube 2333 is communicated with the outflow chamber 232.

[0065] The valve element housing portion 2332 houses a sealing member 2334 , a valve element 2335 , and a biasing member 2336 .

[0066] The sealing member 2334 is arranged adjacent to the inner peripheral wall of the valve core housing portion 2332 on the upstream side (the liquid guide tube 2333 side) of the valve core 2335 in the ink flow direction. The sealing member 2334 is, for example, an O-ring made of an elastic body such as rubber, and its outer peripheral portion is in close contact with the inner peripheral wall of the valve core housing portion 2332. The outer diameter of the sealing member 2334 is larger than the inner diameter of the liquid guide tube 2333. The inner diameter of the sealing member 2334 is smaller than the outer diameter of the valve core 2335.

[0067] The valve core 2335 is composed of a ball (spherical shape) and can move in the valve core housing portion 2332 along the ink flow direction. If the valve core 2335 moves to the upstream side of the ink flow direction, it contacts the inner circumference of the sealing member 2334 and closes the liquid guide tube 2333. Thus, the ejection check valve 233 allows the ink to flow relative to the diaphragm 213 only in the ejection direction, preventing the backflow of the ink.

[0068] The urging member 2336 is disposed on the downstream side (discharging portion 2331 side) in the ink flow direction relative to the valve body 2335. The urging member 2336 is composed of, for example, a compression coil spring, and the coil axis thereof extends along the central axis of the valve body housing portion 2332.

[0069] The upstream end of the force member 2336 in the ink flow direction contacts the valve core 2335 which is a ball. The downstream end of the force member 2336 in the ink flow direction contacts the wall surface of the valve core housing 2332 at the downstream end in the ink flow direction opposite to the valve core 2335. Thus, the force member 2336 applies force to the valve core 2335 in the direction of contact with the sealing member 2334, that is, in the upstream side of the ink flow direction. The ejection check valve 233 prevents the backflow of ink by making the valve core 2335 contact with the inner peripheral portion of the sealing member 2334 through the force member 2336, so that the ink flows only in the ejection direction relative to the diaphragm 213.

[0070] In addition, when the diaphragm pump 21 is operated, the valve core 2335 overcomes the force of the biasing member 2336 by the ejection force thereof and moves to the downstream side in the ink flow direction, and the ink flows out from the outflow chamber 232 through the ejection check valve 233 to the outside of the ejection unit 23. When the diaphragm pump 21 is stopped, the valve core 2335 moves to the upstream side in the ink flow direction by the force of the biasing member 2336 and contacts the sealing member 2334, thereby preventing the backflow of the ink.

[0071] By using a spherical check valve whose valve core is formed of a ball as the suction check valve 223 and the discharge check valve 233, it is possible to prevent the backflow of ink with high accuracy. Therefore, the ink conveying performance of the ink supply device 20 can be improved.

[0072] In addition, the suction check valve 223 can be installed and removed relative to the suction box 221 of the suction unit 22. In addition, the discharge check valve 233 can be installed and removed relative to the discharge box 231 of the discharge unit 23. According to these structures, the structure of the check valve can be easily changed. For example, if the risk of foreign matter mixing into the ink is low, an umbrella valve or a duckbill valve can also be used instead of the ball check valve. In this way, the ink supply device 20 can be made low-cost.

[0073] In addition, if Figure 8 As shown, the suction unit 22 and the discharge unit 23 sandwich the filter units 24A and 24B, and on one side of the reciprocating direction of the diaphragm 213 ( Figure 8 The suction unit 22 and the discharge unit 23 are arranged to overlap with the diaphragm pump 21 in such a manner that the inflow chamber 222 and the outflow chamber 232 are opposite to the diaphragm 213 on one side of the reciprocating direction of the diaphragm 213, sandwiching the filter units 24A and 24B and overlapping each other. Moreover, the suction unit 22, the discharge unit 23, and the filter units 24A and 24B are detachable from each other.

[0074] In addition, in the present embodiment, although the diaphragm pump 21 (diaphragm housing 216), the suction unit 22, the filter units 24A and 24B, and the discharge unit 23 are connected in this order, the suction unit 22 and the discharge unit 23 may be exchanged. In this case, the outer shapes of the suction box 221 and the discharge box 231 are changed so that the diaphragm pump 21 (diaphragm housing 216), the discharge unit 23, and the suction unit 22 can be connected in this order. Alternatively, the suction check valve 223 and the discharge check valve 233 may be exchanged.

[0075] In addition, at least one of the filter units 24A and 24B as optional units needs only to be provided.

[0076] According to the above structure, an optional unit (filter unit 24A, 24B) is arranged on the upstream side of the ink flow direction of the ejection unit 23 located on the ink ejection side relative to the diaphragm 213. The optional unit can be set as a structure that performs various treatments on the circulating ink. Therefore, for the ink ejected from the diaphragm pump 21, it is possible to suppress the deterioration of the ink quality or achieve the high quality of the ink.

[0077] In addition, the optional unit is a filter unit 24A, 24B having filters 241A, 241B covering the flow cross section of the ink. According to this structure, foreign matter contained in the ink flowing into the suction unit 22 can be removed by the filters 241A, 241B. As a result, the ink ejected from the ejection unit 23, that is, the ink supply device 20, can be made free of foreign matter, and damage to the recording head 52 and the like and a decrease in image quality can be suppressed.

[0078] In addition, one of the suction unit 22 and the ejection unit 23 as the ejection unit is arranged adjacent to the diaphragm 213 in a manner facing each other, and the other is arranged overlapping the one. Moreover, either the suction unit 22 or the ejection unit 23 can be arranged adjacent to the diaphragm 213. That is, the configuration of the ink suction unit and the ejection unit relative to the diaphragm pump 21 can be arbitrarily changed, and the freedom of the structure of the ink flow path can be increased. As a result, the ink supply device 20 can efficiently transport ink in accordance with the various structures of the inkjet recording device 1 at the installation destination.

[0079] The filter unit 24A includes a filter 241A and a filter case 242A. The filter unit 24B includes a filter 241B and a filter case 242B. The filter unit 24A is arranged on the upstream side of the filter unit 24B in the ink flow direction.

[0080] The filter units 24A and 24B have the same basic structure except for the mesh size of the filters 241A and 241B. Therefore, in the following description, the identification symbols "A" and "B" may be omitted unless otherwise specified.

[0081] The filter 241 is a sheet-like member extending in a direction orthogonal to the radial direction Dr (reciprocating direction of the diaphragm 213) of the output shaft 211x of the motor 211 and parallel to the diaphragm 213. The filter 241 is composed of, for example, a metal mesh filter. The filter 241 is held by a filter housing 242 and covers the flow cross section of the ink.

[0082] The mesh size (opening size, opening rate) of the filters 241A and 241B is different from each other. For example, the mesh size of the filter 241B is finer (opening size, opening rate is small) than the filter 241A located upstream in the ink flow direction. That is, the mesh size of the filters 241A and 241B becomes finer as the two filter units 24A and 24B move from the suction unit 22 side to the discharge unit 23 side.

[0083] According to the above structure, foreign matters of different sizes contained in the ink can be removed in sequence by the two filter units 24A and 24B. In this way, by adjusting the size of the mesh of the filters 241A and 241B, foreign matters contained in the ink can be removed more effectively. In addition, the mesh clogging of the filters 241A and 241B can be suppressed.

[0084] Specifically, the filter 241A has finer mesh (smaller opening size and opening ratio) than the filter 225 of the suction unit 22 located upstream in the ink flow direction. That is, the meshes of the three filters 225, 241A, and 241B become finer from the suction unit 22 side toward the discharge unit 23 side.

[0085] According to the above structure, foreign matters of different sizes contained in the ink can be removed in sequence by the three filters 225, 241A, and 241B. In this way, by adjusting the size of the mesh of the filters 225, 241A, and 241B, foreign matters contained in the ink can be further effectively removed. In addition, the mesh clogging of the filters 225, 241A, and 241B can be suppressed.

[0086] Furthermore, in addition to Fig.12 , also use Fig.13 and Fig.14 The detailed structure of the filter unit 24 will be described. Fig.13 yes Fig.12 24 is a top view of the filter unit 24. Fig.14 yes Fig.12 2 is a top view of the filter unit 24, and is a diagram showing a state where the filter 241 is removed. Fig.13 and Fig.14 In FIG. 1 , identification symbols “A” and “B” of the filter unit 24 are omitted.

[0087] The filter case 242 of the filter unit 24 has an outer cylinder portion 2421 , an inner cylinder portion 2422 , a flat plate portion 2423 , a filter holding portion 2424 , a filter facing portion 2425 , a plurality of flow holes 2426 , and a plurality of protrusions 2427 .

[0088] The outer cylinder portion 2421 is arranged at the central part of the filter housing 242. The inner cylinder portion 2422 is arranged on the radial inner side of the outer cylinder portion 2421. The outer cylinder portion 2421 and the inner cylinder portion 2422 are formed into a cylindrical shape extending along the radial direction Dr (the reciprocating direction of the diaphragm 213) of the output shaft 211x of the motor 211. In the ink flow direction in the filter unit 24, the inner cylinder portion 2422 is arranged at the upstream part, and the outer cylinder portion 2421 is arranged at the downstream part. The interiors of the outer cylinder portion 2421 and the inner cylinder portion 2422 are connected at the approximately central part of the ink flow direction. The downstream part of the ink flow direction of the inner cylinder portion 2422 protrudes to the downstream side in the outer cylinder portion 2421. The ink flows along the radial direction Dr in the order of the inner cylinder portion 2422 and the outer cylinder portion 2421.

[0089] The flat plate portion 2423 extends in a flange shape toward the outside of the outer cylinder portion 2421 in a direction orthogonal to the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213). The outer shape of the flat plate portion 2423 is rectangular when viewed from the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213). The size and shape of the outer shape (rectangular) of the flat plate portion 2423 when viewed from the radial direction Dr are the same as the size and shape of the outer shape (rectangular) of the suction box 221 and the discharge box 231 when viewed from the radial direction Dr. The flat plate portion 2423 is opposite to and in contact with the flat plate portion 2423 of the other filter unit 24, the suction box 221, or the discharge box 231 in the ink flow direction.

[0090] The filter holding portion 2424 is formed in the outer cylinder portion 2421 at the downstream end of the inner cylinder portion 2422 protruding toward the downstream side of the ink circulation direction. The filter holding portion 2424 is configured as an annular plane facing the downstream side of the ink circulation direction. The outer periphery of the ink circulation path of the filter 241 is attached to the filter holding portion 2424. Thus, the filter holding portion 2424 holds the outer periphery of the ink circulation path of the filter 241.

[0091] The filter opposing portion 2425 is located inside the inner cylinder 2422, further inside the ink flow path than the filter holding portion 2424. The filter opposing portion 2425 is arranged separately from the filter 241 on the upstream side relative to the downstream end of the inner cylinder 2422 in the ink flow direction. The filter opposing portion 2425 is formed into a circular flat plate shape extending along the flow cross section of the ink in a direction orthogonal to the radial direction Dr (the reciprocating direction of the diaphragm 213) of the output shaft 211x. The filter opposing portion 2425 is opposite to the filter 241 in the ink flow direction.

[0092] A plurality of flow holes 2426 are formed in the filter opposing portion 2425. The plurality of flow holes 2426 are arranged at predetermined positions in a direction orthogonal to the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213). The plurality of flow holes 2426 penetrate the filter opposing portion 2425 along the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213). The plurality of flow holes 2426 allow ink to circulate. That is, for example, the ink reaching the filter unit 24 from the inflow chamber 222 of the suction unit 22 flows toward the filter 241 through the plurality of flow holes 2426.

[0093] A plurality of protrusions 2427 are formed on the filter-opposing portion 2425. Specifically, the plurality of protrusions 2427 are formed on the opposing surface of the filter-opposing portion 2425 that is opposed to the filter 241 in the ink flow direction, and on the surface on the opposite side thereof. The plurality of protrusions 2427 are arranged at predetermined positions in a direction orthogonal to the radial direction Dr (the reciprocating direction of the diaphragm 213) of the output shaft 211x.

[0094] The plurality of protrusions 2427 protrude in the ink flow direction toward the filter 241 along the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213). Specifically, the plurality of protrusions 2427 formed on the opposing surface of the filter opposing portion 2425 that is opposed to the filter 241 protrude toward the filter 241. On the other hand, the plurality of protrusions 2427 formed on a surface opposite to the opposing surface of the filter opposing portion 2425 that is opposed to the filter 241 protrude toward the filter 241 provided in the other filter unit 24 adjacent to the radial direction Dr of the output shaft 211x or the filter 225 provided in the suction unit 22. The protruding length of the protrusion 2427 is preferably a length that just contacts the filters 241 and 225, but may be shorter than the length that contacts the filters 241 and 225.

[0095] According to the above structure, the filter 241 that attempts to displace in the ink flow direction due to the pressure when the ink flows can be supported by the plurality of protrusions 2427. This can suppress the positional displacement and deformation of the filter 241. Therefore, appropriate ink conveying performance can be achieved.

[0096] In addition, the plurality of protrusions 2427 formed on one side of the filter opposing portion 2425 in the ink circulation direction and the plurality of protrusions 2427 formed on the other side are respectively arranged at the same position in the direction orthogonal to the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213). In addition, the plurality of protrusions 2227 formed on the suction unit 22 and the plurality of protrusions 2327 formed on the ejection unit 23 are also respectively arranged at the same position in the direction orthogonal to the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213) as the plurality of protrusions 2427 formed on the filter unit 24. That is, the top ends of the protruding directions of the plurality of protrusions 2427, 2227, and 2327 are respectively opposite to each other in the ink circulation direction.

[0097] According to the above structure, the filters 241 and 225 can be sandwiched in the ink flow direction by the top ends of the plurality of protrusions 2427, 2227, and 2327. This can improve the effect of suppressing the positional deviation and deformation of the filters 241 and 225. Therefore, it is possible to maintain appropriate ink conveying performance.

[0098] Next, a modification of the ink supply device 20 will be described. Fig.15 It is a top view of the optional unit (heater unit 24C) of Modification 1. Fig.16 FIG. 2 is a top view of an optional unit (heater unit 24D) of variant example 2. Figures 1 to 14The embodiments to be described are the same, and therefore common components are denoted by the same reference numerals or names as before, and description thereof may be omitted.

[0099] The ink supply device 20 may also include Fig.15 or Fig.16 Heater units 24C, 24D are shown as optional units.

[0100] like Fig.15 As shown, the heater unit 24C has a heating portion 246, for example, inside the inner cylinder portion 2422. The heating portion 246 is composed of a coil arranged in a direction orthogonal to the radial direction Dr of the output shaft 211x of the motor 211 in the inner cylinder portion 2422. The ink passing through the inner cylinder portion 2422 of the heater unit 24C is heated by the heating portion 246.

[0101] like Fig.16 As shown, the heater unit 24D has a heating portion 247 inside the inner cylinder portion 2422. The heating portion 247 is composed of a ceramic heater mounted on the filter opposing portion 2425 in the inner cylinder portion 2422. The ink in the inner cylinder portion 2422 passing through the heater unit 24D is heated by the heating portion 247.

[0102] As described above, the optional unit may be the heater units 24C and 24D having the heating units 246 and 247 for heating the ink. According to this structure, the ink flowing into the suction unit 22 can be heated by the heating units 246 and 247. Thus, the temperature of the ink ejected from the ejection unit 23, that is, the ink supply device 20 can be appropriately managed, and the image quality can be improved.

[0103] In addition, if Figure 8 and Fig. 9 As shown in FIG. 1 , the ink supply device 20 includes three outer sealing members 25A, 25B, and 25C. The three outer sealing members 25A, 25B, and 25C are O-rings made of an elastic body such as rubber.

[0104] The outer seal member 25A is disposed between the suction unit 22 and the filter unit 24A. Specifically, the outer seal member 25A is disposed between the inner edge of the opening 222b of the suction unit 22 and the outer edge of the upstream portion of the inner cylinder 2422 of the filter unit 24A in the ink flow direction.

[0105] The outer seal member 25B is disposed between the filter unit 24A and the filter unit 24B. Specifically, the outer seal member 25B is disposed between the inner edge of the downstream portion of the outer cylinder 2421 of the filter unit 24A in the ink flow direction and the outer edge of the upstream portion of the inner cylinder 2422 of the filter unit 24B in the ink flow direction.

[0106] The outer seal member 25C is disposed between the filter unit 24B and the ejection unit 23. Specifically, the outer seal member 25C is disposed between the inner edge of the downstream portion of the outer cylinder 2421 of the filter unit 24B in the ink flow direction and the outer edge of the opening 232a of the ejection unit 23.

[0107] The three outer sealing members 25A, 25B, and 25C are respectively disposed between the suction unit 22, the ejection unit 23, and the filter units 24A and 24B to prevent ink from leaking to the outside. According to this structure, the ink conveying performance can be suppressed from decreasing, and the ink contamination in the inkjet recording device 1 can be prevented.

[0108] In addition, if Figure 6 , Figure 7 and Fig.10 As shown, the ejection unit 23 has a plurality of unit positioning shafts 234. The unit positioning shafts 234 are arranged at the four corners of the ejection box 231 which is rectangular when viewed from the radial direction Dr of the output shaft 211x of the motor 211 (see Figure 7 ). That is, the ejection unit 23 has four unit positioning shafts 234.

[0109] The four unit positioning shafts 234 extend toward the filter unit 24, the suction unit 22, and the diaphragm pump 21. In other words, the four unit positioning shafts 234 extend along the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213). The unit positioning shafts 234 have external threads formed on their top peripheral portions.

[0110] In addition, if Fig.12 and Fig.13 As shown, the filter unit 24 has a plurality of unit positioning holes 245. The plurality of unit positioning holes 245 are arranged at four corners of the filter unit 24 which is rectangular when viewed from the radial direction Dr of the output shaft 211x of the motor 211. That is, the filter unit 24 has four unit positioning holes 245.

[0111] The four unit positioning holes 245 extend toward the discharge unit 23, the suction unit 22, and the diaphragm pump 21. In other words, the four unit positioning holes 245 extend along the radial direction Dr (the reciprocating direction of the diaphragm 213) of the output shaft 211x and penetrate the filter unit 24. Specifically, the four unit positioning holes 245 penetrate the flat plate portion 2423 of the filter housing 242. In addition, the unit positioning holes 245 are not connected to the inside of the outer cylinder 2421 and the inside of the inner cylinder 2422. The four unit positioning shafts 234 are respectively inserted into the four unit positioning holes 245.

[0112] In addition, if Figure 6 and Fig.11As shown, the suction unit 22 has a plurality of unit positioning holes 224. The unit positioning holes 224 are arranged at four corners of the suction housing 221 which is rectangular when viewed from the radial direction Dr of the output shaft 211x of the motor 211. That is, the suction unit 22 has four unit positioning holes 224.

[0113] The four unit positioning holes 224 extend toward the filter unit 24, the discharge unit 23, and the diaphragm pump 21. In other words, the four unit positioning holes 224 extend along the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213) and penetrate the suction box 221. In addition, the unit positioning holes 224 are not connected to the inflow chamber 222. The four unit positioning shafts 234 are respectively inserted into the four unit positioning holes 224.

[0114] In addition, if Figure 6 As shown, the diaphragm housing portion 216 has a plurality of unit positioning holes 2161. The unit positioning holes 2161 are arranged at four corners of the diaphragm housing portion 216 which is rectangular when viewed from the radial direction Dr of the output shaft 211x of the motor 211. That is, the diaphragm housing portion 216 has four unit positioning holes 2161.

[0115] The four unit positioning holes 2161 extend toward the suction unit 22, the filter unit 24, and the ejection unit 23. In other words, the four unit positioning holes 2161 extend along the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213) and penetrate the diaphragm housing portion 216. In addition, the unit positioning holes 2161 are not connected to the ink flow area in the diaphragm housing portion 216. The four unit positioning shafts 234 are respectively inserted into the four unit positioning holes 2161.

[0116] The top ends of the four unit positioning shafts 234 are connected from the side of the diaphragm housing portion 216 opposite to the suction unit 22, the filter unit 24 and the discharge unit 23 ( Figure 6 The four unit positioning shafts 234 are inserted into four nuts 26 to fasten the suction unit 22, the filter unit 24, the discharge unit 23 and the diaphragm receiving portion 216. The four nuts 26 are arranged on the opposite side of the diaphragm receiving portion 216 from the suction unit 22, the filter unit 24 and the discharge unit 23.

[0117] According to the above-mentioned structure, the suction unit 22, the filter unit (optional unit) 24, and the discharge unit 23 can be appropriately positioned relative to the diaphragm pump 21 (diaphragm housing portion 216). In addition, it is possible to suppress ink leakage from the connection portions between the suction unit 22, the filter unit (optional unit) 24, the discharge unit 23, and the diaphragm housing portion 216.

[0118] In addition, if Figure 6 and Figure 7As shown, on the side of the diaphragm housing portion 216 opposite to the suction unit 22, the filter unit 24 and the discharge unit 23 ( Figure 6 A plate-shaped member 27 is disposed on one side of the diaphragm housing 216 and the four nuts 26. Fig.17 yes Figure 6 A three-dimensional view of the plate-like member 27 of the ink supply device 20.

[0119] The plate-like member 27 is formed into a C-shape when viewed from the radial direction Dr (reciprocating direction of the diaphragm 213) of the output shaft 211x of the motor 211. The outer shape of the plate-like member 27 is substantially rectangular when viewed from the radial direction Dr of the output shaft 211x, and is substantially the same in size and shape as the outer shape (rectangular) of the diaphragm housing portion 216 when viewed from the radial direction Dr. The plate-like member 27 is installed along the diaphragm housing portion 216 by inserting the open portion of the C-shape in plan view into the diaphragm mechanism portion 212.

[0120] The plate-like member 27 has a plurality of plate-like member positioning holes 271. The plate-like member positioning holes 271 are arranged at the four corners of the plate-like member 27 whose outer shape is substantially rectangular when viewed from the radial direction Dr of the output shaft 211x. That is, the plate-like member 27 has four plate-like member positioning holes 271. The four plate-like member positioning holes 271 penetrate the plate-like member 27 in the radial direction Dr of the output shaft 211x (the reciprocating direction of the diaphragm 213). The four unit positioning shafts 234 are respectively inserted into the four plate-like member positioning holes 271.

[0121] By providing the plate-like member 27 adjacent to the diaphragm housing portion 216, it is possible to improve the fastening strength of the suction unit 22, the filter unit 24, the ejection unit 23, and the diaphragm housing portion 216 by the unit positioning shaft 234. Therefore, it is possible to effectively suppress ink leakage from the connection portions between the suction unit 22, the filter unit 24, the ejection unit 23, and the diaphragm housing portion 216.

[0122] As mentioned above, although embodiment of this invention was described, the scope of this invention is not limited to this, Various changes can be made and it can be implemented without departing from the scope of this invention.

[0123] For example, in the above embodiment, the ink supply device 20 includes two filter units 24A and 24B as optional units, but the present invention is not limited to this structure. The optional units may be three or more. For example, the ink supply device 20 may include any one of the heater units 24C and 24D in addition to the two filter units 24A and 24B.

Claims

1. A liquid supply device, characterized in that: have: Diaphragm pumps, which transport liquids through the reciprocating movement of a diaphragm; a suction unit having a suction check valve for allowing the liquid to flow relative to the diaphragm only in a suction direction and an inflow chamber for the liquid to flow in through the suction check valve; a discharge unit including a discharge check valve for allowing the liquid to flow relative to the diaphragm only in a discharge direction, and an outflow chamber for allowing the liquid flowing in from the inflow chamber to flow out toward the discharge check valve; as well as An optional unit is arranged between the suction unit and the ejection unit, The suction unit and the discharge unit sandwich at least one of the optional units, and are arranged to overlap each other in such a manner that the inflow chamber and the outflow chamber are continuously opposed to the diaphragm on one side of the reciprocating direction of the diaphragm. The suction unit, the ejection unit, and the optional unit are detachable from each other.

2. The liquid supply device according to claim 1, characterized in that: The optional unit is a filter unit having a filter covering a flow cross section of the liquid.

3. The liquid supply device according to claim 2, characterized in that: A plurality of the filter units are arranged between the suction unit and the discharge unit, and the plurality of the filter units include filters having mesh sizes different from each other. The plurality of filter units have meshes of the filters that become finer as they move from the suction unit side toward the discharge unit side.

4. The liquid supply device according to claim 2, characterized in that: The filter unit has: the filter; a filter holding portion that holds an outer peripheral portion of a liquid flow path of the filter; a filter-opposing portion, which is located inside the liquid flow path than the filter holding portion, is separated from the filter in the liquid flow direction, and is opposed to the filter in the liquid flow direction; A plurality of flow holes are formed in the filter opposing portion for allowing the liquid to flow; as well as A plurality of protrusions are formed on the filter-facing portion and protrude toward the filter.

5. The liquid supply device according to claim 1, characterized in that: The optional unit is a heater unit having a heating portion that heats the liquid.

6. The liquid supply device according to claim 1, characterized in that: One of the suction unit and the ejection unit has a plurality of unit positioning shafts, and the plurality of unit positioning shafts are inserted into a plurality of unit positioning holes of the other of the suction unit and the ejection unit and the optional unit. The diaphragm pump includes a diaphragm housing portion for housing the diaphragm. The liquid supply device includes a plate-shaped member, which is arranged on the opposite side of the diaphragm accommodating portion from the suction unit, the discharge unit, and the optional unit, and is formed into a C shape when viewed from the reciprocating direction of the diaphragm. The plate-like member has a plurality of plate-like member positioning holes into which the plurality of unit positioning shafts are inserted.

7. The liquid supply device according to claim 1, characterized in that: The ejection check valve is a spherical check valve whose valve core is composed of a ball.

8. The liquid supply device according to claim 1, characterized in that: The suction check valve is attachable to and detachable from a casing of the suction unit.

9. The liquid supply device according to claim 1, characterized in that: The discharge check valve is attachable to and detachable from a casing of the discharge unit.

10. An inkjet recording device, characterized in that: have: a recording head that ejects ink to record an image; and The liquid supply device according to claim 1 supplies ink to the recording head.

Images