JP2008149646A - Fluid feeding apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid feeding apparatus which improves stability of pressure adjusting operation and is advantageous in miniaturization and assembly workability. <P>SOLUTION: The fluid feeding apparatus has a pressure reducing valve 20 for depressurizing a pressure room 15 which stores ink introduced from an inlet 17 and guides it to an outlet 18 to a specified pressure. The pressure reducing valve 20 includes a valve body 23 moving between a valve closing position for shutting introduction of the ink into the pressure room 15 and a valve opening position for introducing the ink into the pressure room 15, a displacing means for displacing the valve body 23 from the valve closing position to the valve opening position when the pressure in the pressure room 15 is depressurized to the specified pressure, and an O-ring 24 which comes into tight contact with the valve body 23 and the outer peripheral part of the inlet 17 to seal the inlet 17 when the valve body 23 is positioned at the valve closing position. By supporting the valve body 23 by a sheet spring 22 provided in a storing flow path 27 communicating with the inlet 17, the valve body 23 is held at the valve closing position until the pressure in the pressure room 15 is depressurized to the specified pressure. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention mainly relates to a fluid supply apparatus that improves the stability of a pressure adjustment operation that adjusts a fluid pressure.

  BACKGROUND ART A fluid supply device that adjusts a fluid outlet pressure is used in a liquid ejecting apparatus that ejects liquid onto a target. As such a liquid ejecting apparatus, an ink jet printer (hereinafter simply referred to as a printer) that ejects ink onto a recording sheet is known. The printer includes a recording head that ejects ink supplied from an ink cartridge as ink droplets, and a carriage that carries the recording head and reciprocates on recording paper. When an image signal created based on the image data is input to the printer, the recording head mounted on the carriage ejects ink droplets while reciprocating on the recording paper, and printing according to the image data is performed. Is supposed to do.

  In such a printer, when the ink cartridge is mounted on the carriage, a moving space for the ink cartridge is required as the carriage reciprocates, and the size of the printer is increased by the moving space. In view of this, printers that are reduced in size and thickness employ a so-called off-carriage type in which an ink cartridge is not mounted on a carriage.

  In the off-carriage type, the ink cartridge for storing ink is disposed at a position away from the carriage. For this reason, the ink stored in the ink cartridge is pressurized by the atmosphere or the like in the ink cartridge, and is pumped to a carriage disposed at a distant position. Here, when the pressure of the ink pumped to the carriage fluctuates, the size of the ink droplets ejected from the recording head becomes non-uniform, resulting in a problem of poor printing.

  Therefore, conventionally, in such carriages, proposals have been made to adjust the supply pressure of ink supplied to the recording head, and a pressure reducing valve for reducing the pressure of ink supplied to the recording head to a predetermined pressure has been provided. . The pressure reducing valve is provided with a valve body that reciprocates between a position for closing the ink flow path (valve closing position) and a position for opening the flow path (valve opening position). The valve body is always urged toward the valve closing position by the urging force of the coil spring, and is displaced to the valve opening position by the elastic force of the diaphragm relative to the ink supply pressure.

  That is, when the valve body is arranged at the valve closing position by the biasing force of the coil spring, the ink supply pressure is reduced relative to the amount of ink consumed on the downstream side (recording head) of the valve body. It has become. When the ink supply pressure is reduced to a predetermined pressure, the valve element arranged at the valve closing position is displaced to the valve opening position under the pressing force of the diaphragm, and the supply flow path is opened. When the supply flow path is opened and the ink supply pressure is increased to a predetermined pressure or higher, the pressing force by the diaphragm is released, and the valve element located at the valve open position is displaced to the valve close position, and the supply flow path Will come to close again. The pressure of the ink supplied to the recording head is adjusted by such reciprocation of the valve body.

  In the conventional pressure reducing valve, a cylindrical coil spring having a coil diameter substantially the same as the outer diameter of the valve body is employed. The cylindrical coil spring is disposed at a position opposite to the seal member (O-ring) having an outer diameter smaller than the coil diameter and the valve element. When the valve body that receives the urging force of the cylindrical coil spring comes into close contact with the O-ring, the ink flow path connected to the recording head is closed.

  However, in the conventional pressure reducing valve, since the outer diameter of the O-ring is formed smaller than the coil diameter, the urging force of the coil spring is given as the fulcrum (O-ring) on the center side of the outer periphery (power point) of the valve body. Will come to be. Therefore, when the biasing force of the coil spring is biased in the circumferential direction of the outer periphery of the valve body, the valve body comes into close contact with the O-ring only on the side where the bias is biased and is separated from the O-ring on the side opposite to the side where the bias is biased. In other words, if the biasing force of the coil spring is biased in the circumferential direction of the outer periphery of the valve body, the closing performance of the flow path by the valve body is impaired, and the supply pressure is reduced despite the valve body being located at the valve closing position. The pressure cannot be reduced to a predetermined pressure. As a result, the pressure adjustment of the ink supplied to the recording head is insufficient. Such problems can be mitigated, for example, by applying smoothing such as grinding to both ends of the coil spring. However, high accuracy is required for the smoothing and coil spring assembly, and the productivity of the pressure reducing valve is reduced. It will be seriously damaged.

Therefore, a pressure reducing valve disclosed in the following Patent Document 1 has been proposed as a pressure reducing valve capable of improving the stability of the pressure adjusting operation for adjusting the liquid outlet pressure. In the pressure reducing valve described in Patent Document 1, the valve body is always urged toward the valve closing position by a conical coil spring so that the upper side surface of the storage chamber and the flange portion are in close contact with the O-ring. When the ink in the pressure chamber is consumed and the pressure is reduced to a predetermined pressure, when the O-ring is separated from the upper surface by the operating force of the operating lever against the biasing force of the coil spring, the upper end of the coil spring is The valve body is urged toward the upper side surface at the center side of the O-ring facing each other through the collar portion.
JP-A-2005-343123

  However, in the pressure reducing valve described in Patent Document 1, the conical coil spring is used so that the inside of the seal surface can be urged, but the urging force is not necessarily applied to the center of the seal surface. Therefore, depending on the coil spring assembly state, the position where the urging force of the coil spring is applied deviates from the center of the seal surface, the load does not work evenly on the seal surface, and the seal performance becomes uneven, making it impossible to secure the seal performance. Or the pressure adjustment may vary and the stability of the pressure adjustment may be lacking. Further, the pressure chambers and the valve bodies are required for the number of types of ink, and so much time is required for the assembly process to assemble the coil spring with high accuracy. In addition, the smaller the pressure chamber, the smaller the coil spring that is required. However, there is a limit to the accuracy and miniaturization of the coil spring. There was a problem that would be necessary. In addition, as described above, in the pressure reducing valve using the coil spring in the flow path, bubbles attached to the coil spring are not completely removed during the initial ink filling, and the amount of ink consumed for the initial filling increases. There was also a risk of missing dots.

  The present invention has been made in view of such circumstances, and its object is to provide a fluid supply device that improves the stability of the pressure adjustment operation for adjusting the fluid discharge pressure and is advantageous in terms of downsizing and assembly. And

  In order to achieve the above object, a fluid supply apparatus according to the present invention is a fluid supply apparatus having a pressure reducing valve that stores a fluid introduced from an introduction port and depressurizes a pressure chamber that leads to a discharge port to a predetermined pressure. The pressure reducing valve includes a valve body that moves between a valve closing position for blocking the introduction of fluid into the pressure chamber and a valve opening position for introducing fluid into the pressure chamber, and the pressure in the pressure chamber is reduced to the predetermined pressure. Then, the displacement means for displacing the valve body from the valve closing position to the valve opening position, and when the valve body is located at the valve closing position, the introduction port is sealed in close contact with the outer periphery of the valve body and the introduction port. The valve body is supported by a plate-like urging member provided in a flow path having a sealing portion and communicating with the introduction port, whereby the pressure in the pressure chamber is reduced to the predetermined pressure. The gist is that the valve is held in the closed position until it is done.

  That is, according to the present invention, the valve body held in the valve closing position by the plate-like urging member is in close contact with the sealing portion that is in close contact with the outer peripheral portion of the inlet, thereby blocking the introduction of the fluid into the pressure chamber. . And if the fluid in a pressure chamber is derived | led-out and the pressure in the same pressure chamber becomes lower than predetermined pressure, a displacement means will displace and will move a valve body to a valve opening position. The valve element that moves between the valve closing position and the valve opening position is urged toward the valve closing position by the plate-like urging member provided in the flow path communicating with the introduction port.

  In this way, instead of using a conical coil spring as in the past, the valve body is supported by a plate-shaped biasing member provided in the flow path, so that the center of the sealing portion can be biased. By doing so, the valve body and the outer peripheral portion of the inlet port are securely in close contact with the sealing portion, and the sealing by the sealing portion is made uniform and the sealing performance is ensured, and the pressure adjustment varies. The stability and reliability of pressure adjustment can be improved by significantly reducing the pressure. Further, the plate-like urging member is not only easily downsized, but accuracy can be secured even if the plate-like urging member is downsized, and the cost does not increase so much. In addition, the ease of assembly is greatly improved, and the time required for assembly can be greatly reduced. In addition, since a plate-shaped biasing member that is extremely simple in shape exists in the flow path, bubbles are easily removed during the initial ink filling, and the amount of ink consumed for the initial filling is reduced, and the dot missing. Can greatly reduce the probability of.

  In the present invention, when the plate-like biasing member biases the valve body toward the valve closing position at a position substantially at the center of the sealing portion in the valve body, By energizing at the substantial center position, the outer periphery of the inlet port is securely in close contact with the sealing part, the sealing by the sealing part is made uniform to ensure the sealing performance, and the variation in pressure adjustment is greatly increased. The stability and reliability of the pressure adjustment can be improved by reducing the pressure to a small value.

  In the present invention, when a contact projection that contacts the plate-like biasing member is formed on the side of the valve body that is supported by the plate-like biasing member at a position that is substantially the center of the sealing portion. Makes it possible to urge the valve body at the substantial center position of the sealing portion by contact between the contact protrusion and the plate-like urging member, so that the valve body and the outer peripheral portion of the introduction port are securely attached to the sealing portion. It is possible to improve the stability and reliability of the pressure adjustment by making the sealing by the sealing portion uniform and ensuring the sealing performance, and reducing the pressure adjustment variation significantly.

  In the present invention, in the flow path in which the plate-like urging member is accommodated, the valve element is opened from the valve closing position between the surface of the plate-like urging member opposite to the valve element and the wall surface of the flow path. If the deformation-allowing space for the plate-like biasing member that can be displaced to the position is formed, the plate-like biasing member easily deforms within the deformation-allowing space due to the displacement of the displacement means, so that the valve The body can be moved from the valve closing position to the valve opening position, and pressure adjustment can be performed reliably and stably.

  In the present invention, the flow path in which the plate-like urging member is accommodated has a gap between the valve-side surface of the plate-like urging member and the flow wall surface in a state where the valve body is supported at the valve closing position. When the plate-like biasing member is deformed by the displacement of the displacement means, the plate-like force due to the surface tension of the fluid flowing into the gap between the channel wall surface and the plate-like biasing member is deformed. The deformation resistance of the biasing member is reduced. For this reason, pressure adjustment can be performed reliably and stably.

  In the present invention, when the sealing portion is an O-ring formed on the valve body and disposed on the introduction port side of the collar portion that closes the introduction port, on the side opposite to the introduction port of the collar portion. The abutting plate-like urging member urges the flange portion toward the introduction port side to closely contact the O-ring disposed on the introduction port side of the flange portion with the outer peripheral portion of the introduction port. Therefore, the collar portion can be urged toward the introduction port by using the O-ring and one end of the plate-like urging member abutting inside the O-ring as a fulcrum and a force point, respectively. As a result, the flange portion and the outer peripheral portion of the inlet can be reliably brought into close contact with the O-ring. Therefore, by disposing the valve body at the valve closing position, the introduction of the fluid into the pressure chamber can be reliably blocked, and as a result, the stability of the pressure adjustment operation by the pressure reducing valve can be improved.

  In the present invention, the flange portion of the valve body is between a sliding contact surface that is slidably contacted along an inner peripheral surface of the valve body housing channel that houses the valve body, and an inner circumferential surface of the valve body housing channel. When a notch part that forms a gap is provided, the collar part can be guided along the inner peripheral surface of the valve body accommodating flow path, and displacement of the valve body can be avoided. Furthermore, the sliding load of the valve body can be reduced, and the flow path resistance of the fluid can be reduced. As a result, the reciprocation of the valve body can be made smoother.

  In the present invention, the displacement means includes a flexible film that forms a part of the pressure chamber and displaces inward of the pressure chamber when the pressure in the pressure chamber becomes lower than a predetermined pressure, and the flexibility In the case of comprising an operating lever for displacing the valve body to the valve opening position against the urging force of the plate-like urging member with an activating force obtained by multiplying the displacement force due to the displacement of the film, The actuating lever displaces the valve body to the valve opening position by the actuating force obtained by multiplying the displacement force of the flexible film. Therefore, the pressure receiving area of the flexible film can be reduced, and a small and light pressure reducing valve with improved stability of the pressure adjusting operation can be realized.

  Hereinafter, an embodiment in which the fluid supply apparatus of the present invention is applied to an ink jet recording apparatus as a fluid ejecting apparatus will be described.

  FIG. 1 is a schematic perspective view showing a printer 50 as an ink jet recording apparatus, and FIG. 2 is an explanatory view for explaining the ink flow path of the printer 50.

  A printer 50 as a fluid ejecting apparatus includes a frame 51, a paper feed tray 52, and a paper discharge tray 53. The frame 51 covers the entire apparatus of the printer 50. A paper feed tray 52 is provided on the upper side of the frame 51, and a paper discharge tray 53 is provided on the front side of the frame 51. The paper feed tray 52 guides the recording paper as a target into the printer 50, and the paper discharge tray 53 guides the printed recording paper to the outside of the printer 50 and discharges it.

  A guide member 54 is installed in the printer 50 along the longitudinal direction of the frame 51. The guide member 54 supports the carriage 10 so as to be movable. The carriage 10 is connected and driven by a carriage motor (not shown). When the carriage motor is driven to rotate, the carriage 10 receives the driving force to reciprocate along the direction along the guide member 54, that is, along the main scanning direction X.

  A first ink cartridge C1 (hereinafter simply referred to as a first cartridge C1) is connected to the carriage 10 via a tube T1. The first cartridge C1 contains liquid ink as a fluid, and contains an ink pack B that contains black ink. The ink pack B is formed in a bag shape by a flexible sheet or the like and encloses black ink so that it can be led out. The first cartridge C1 contains an ink absorbing material 55 that absorbs ink. The ink absorbing material 55 is made of, for example, a porous material that absorbs ink, such as a sheet-like sponge. The first cartridge C1 is provided with a tube T7 for introducing ink including air into the first cartridge C1.

  The inside of the first cartridge C1 is communicated with the inside of the second ink cartridge C2 (hereinafter simply referred to as the second cartridge C2) via the tube T2. In the second cartridge C2, as shown in FIG. 6, ink packs C, M, YL, LC, and LM for storing cyan, magenta, yellow, light cyan, and light magenta inks are stored. Like the ink pack B, the ink packs C, M, YL, LC, and LM are formed in a bag shape by a flexible sheet or the like and enclose various inks that are opposed to each other. These ink packs C, M, YL, LC, and LM are connected to the connection port 26 of the carriage 10 through the opposite tubes T3.

  Then, when ink including air is introduced into the first cartridge C1, only the ink is absorbed by the ink absorber 55. Then, only the atmosphere introduced into the first cartridge C1 is sent into the second cartridge C2 through the tube T2, and the insides of the first and second cartridges C1 and C2 are made to have the same pressure. As a result, the ink packs B, C, M, YL, LC, and LM of each color are pressurized to the same pressure, and the inks of each color are pumped into the carriage 10 via T1 and T3, respectively. Note that an opening device 56 is connected to the second ink cartridge C2 via a tube T4. The opening device 56 releases the pressure in the first and second cartridges C1, C2 as appropriate, and avoids excessive pressurization of the ink packs B, C, M, YL, LC, LM of each color. I have to.

  A platen 57 is disposed at a position in the printer 50 that is parallel to the guide member 54. The platen 57 is a support for supporting the recording paper, and a paper feed mechanism (not shown) is provided on the upper surface thereof. The paper feed mechanism feeds the recording paper inserted from the paper feed tray 52 along the direction orthogonal to the main scanning direction X, that is, the sub-scanning direction Y.

  A recording head 30 is mounted on the lower surface of the carriage 10 and facing the platen 57 (recording paper). A nozzle forming surface 59 is formed on the lower surface of the recording head 30. A large number of fluid ejection nozzles 60 (hereinafter simply referred to as nozzles 60) are formed on the nozzle forming surface 59. The ink of each color is supplied to the nozzle 60 via each storage chamber 21 of the carriage 10. A vibration plate 61 and a piezo element 62 are provided on the upper portion of the nozzle 60. In the present embodiment, the nozzle row composed of a large number of nozzles 60 per row is formed with 6 rows opposed to the ink of each color. However, the present invention is not limited to this, and the number of nozzle rows may be changed as appropriate.

  The diaphragm 61 is a plate material that enables vibration according to the expansion and contraction of the piezo element 62. The piezo element 62 expands and contracts its length along the ink ejection direction in accordance with an image signal generated based on the print image data. When an image signal is input to the piezo element 62, the diaphragm 61 vibrates in accordance with the expansion and contraction of the piezo element 62, and the volume in the nozzle 60 is enlarged or reduced. When the volume in the nozzle 60 is reduced, the ink in the nozzle 60 is ejected as ink droplets. On the other hand, when the volume in the nozzle 60 increases, a negative pressure is formed in the nozzle 60, and the ink of each color is supplied into the corresponding nozzle 60 by this negative pressure.

  That is, the printer 50 feeds the recording paper along the sub-scanning direction Y and reciprocates the carriage 10 along the main scanning direction X. At the same time, the printer 50 drives the piezo element 62 with an image signal generated based on the print image data to eject ink droplets from the recording head 30. Accordingly, the printer 50 performs printing based on the print data on the recording paper.

  A non-printable area (home position) in which the carriage 10 is disposed when the printer 50 is in a print pause state is provided on one side of the frame 51. A cap holder 63 is provided in the non-printing area.

  The cap holder 63 is formed in a box having an upper surface opened, and is supported by an elevating unit (not shown) attached to the frame 51 so as to be movable up and down. In the cap holder 63, a cap 64 as a sealing means is disposed. The cap 64 is a box having an upper surface opened, and an upper edge thereof is formed of a flexible member made of synthetic resin or the like, and is supported and fixed to the cap holder 63.

  An absorbing material 65 that absorbs ink or the like is fixed inside the cap 64. The absorbent material 65 is, for example, a sheet-like sponge or the like, and is formed of a porous material. On the bottom surface of the cap 64, through holes 66 a and 66 b that penetrate from the inside of the cap 64 to the bottom surface of the cap holder 63 are formed. The through hole 66a communicates with the suction side of the gear pump GP via the tube T5. The gear pump GP is a pump that transmits the rotational driving force of a pump motor (not shown) to the gears G1 and G2, and sucks and discharges ink, air, and the like in the cap 64 connected to the suction side. The through hole 66b is connected to the open valve V1 through the tube T6. The release valve V1 is a valve that is opened to the atmosphere in the cap 64 by opening the valve.

  When the carriage 10 (recording head 30) is in the non-printing area, when the cap holder 63 is moved upward, the upper edge of the cap 64 contacts the nozzle forming surface 59 to seal each nozzle 60. At this time, when the gears G1 and G2 are driven to rotate by driving the pump motor, the gear pump GP sucks the atmosphere in the cap 64 and forms a negative pressure in the cap 64.

  Due to this negative pressure, thickened ink, bubbles, and the like in the recording head 30 are discharged into the cap 64 through the nozzles 60, and cleaning is performed. Then, the ink discharged into the cap 64 is sucked by the gear pump GP, and the release valve V1 is opened. Thereby, the ink in the cap 64 is sucked and the negative pressure is released. Further, since the negative pressure in the cap 64 is released, the cap 64 can be separated from the nozzle forming surface 59 while avoiding vibrations due to a pressure difference or the like even if the elevating part is moved downward.

  An adjusting device 67 is connected to the discharge side of the gear pump GP via a tube T6. The adjusting device 67 adjusts the flow rate and flow velocity of ink discharged from the gear pump GP, and is connected to the inside of the first cartridge C1 (ink absorbing material 55) via the tube T7.

  Then, when the pump motor is driven to rotate the gears G1 and G2, the ink sucked from the cap 64 is introduced into the first cartridge C1 (ink absorbing material 55). At this time, the flow rate and flow rate of the ink to be introduced are adjusted by the adjusting device 67 so that the flow rate and flow rate can be absorbed by the ink absorbing material 55.

  That is, the ink or the like sucked from the cap 64 by the gear pump GP is sequentially fed into the first cartridge C1 after passing through the cap 64, the gear pump GP, and the adjusting device 67. In the ink or the like fed into the first cartridge C1, only the ink is absorbed by the ink absorbing material 55, and only the atmosphere sucked by the gear pump GP flows. Then, the air flows from the first cartridge C1 into the second cartridge C2 through the tube T2, and pressurizes the ink packs B, C, M, YL, LC, and LM to the same pressure. As a result, the ink stored in the ink packs B, C, M, YL, LC, and LM is pressure-fed to the carriage 10, respectively.

  Next, the carriage 10 will be described in detail.

  FIG. 3 is a cross-sectional view showing a carriage 10 to which the fluid supply apparatus of the present invention is applied, and FIG. 4 is a plan view showing an essential part thereof.

  The carriage 10 has a carriage body 11 formed of a substantially rectangular plate member as shown in FIG. On one side surface (upper surface) of the carriage body 11, six groove-like channels 12 are recessed. Each groove-like channel 12 is a channel for ink as a fluid, and is formed in a rectangular shape when viewed from the plane.

  On the opening side (upper side) of the groove-like channel 12, the valve body 23 described later is displaced from the valve closing position to the valve opening position when the pressure in the pressure chamber 15 is reduced to a predetermined pressure. An operating lever 13 that constitutes a displacement means is provided. The actuating lever 13 is a cantilever where a support portion 13 a at one end is supported and fixed to the carriage body 11. The actuating lever 13 is a thin plate member made of metal or the like, and supports its own weight by the support portion 13a. The pressing part 13b which is a part other than the support part 13a of the operating lever 13 is formed of a plate member having higher rigidity than the support part 13a. And when the stress of the bottom face side (lower side) direction of the groove-shaped flow path 12 is applied to the operating lever 13, the operating lever 13 will move down the press part 13b by using the support part 13a as a fulcrum.

  On the upper side of the operation lever 13, a film 14 as a flexible film constituting the displacement means is disposed. The film 14 is heat-sealed to the upper outer edge of each groove-like channel 12. When the film 14 is heat-sealed, the opening of each channel 12 is sealed, and six pressure chambers 15 are formed in the carriage body 11. That is, each rectangular portion of the film 14 that seals each groove-like channel 12 independently forms a pressure receiving portion 14 a of each pressure chamber 15. When the pressure in each pressure chamber 15 decreases, each pressure receiving portion 14 a is displaced toward the lower side in each pressure chamber 15. The operating lever 13 receives the displacement force due to the displacement of the pressure receiving portion 14a and moves down the pressing portion 13b.

  A protective plate 16 is disposed on the upper side of the film 14. As shown in FIG. 1, the protection plate 16 is a rectangular plate member having an outer shape slightly larger than the film 14, and the outer periphery of the film 14 is attached to the carriage body 11. A concave portion 16a is provided at a position on the lower surface of the protective plate 16 and facing the pressure receiving portion 14a. The concave portion 16a is a concave portion that is formed in a rectangular shape when viewed from above, and communicates with the atmosphere via the atmosphere opening port 19 to allow the film 14 to be displaced upward. 4 shows the internal structure of the pressure chamber 15, the description of the protective plate 16 is omitted for convenience of explanation.

  An inlet 17 and an outlet 18 are formed on the bottom surface of each channel 12 and on both sides in the longitudinal direction. The introduction port 17 is a circular hole extending downward from the bottom surface of the pressure chamber 15 and is a flow path for introducing ink as a fluid into the pressure chamber 15. Below the introduction port 17, a pressure reducing valve 20 that stores the ink introduced from the introduction port 17 and depressurizes the inside of the pressure chamber 15 leading to the discharge port 18 to a predetermined pressure is disposed.

  That is, in the carriage body 11, six pressure reducing valves 20 that are opposed to the pressure chambers 15 are disposed below the introduction ports 17. The outlet port 18 is a circular hole that penetrates from the bottom surface of the pressure chamber 15 to the lower surface of the carriage body 11, and is a flow path for leading ink stored in the pressure chamber 15. A recording head 30 as a fluid ejecting head is disposed below the outlet 18. The recording head 30 ejects ink derived from the pressure chamber 15 as ink droplets, and prints on the recording paper as a target as described above.

  Next, the pressure reducing valve 20 disposed on the carriage 10 will be described in detail.

  FIG. 5 is a sectional view showing the pressure reducing valve 20, FIG. 6 is a bottom sectional view showing the carriage 10, and FIG.

  The pressure reducing valve 20 includes a storage chamber 21 as a valve body storage flow path, a plate spring 22 as a plate-like urging member that constitutes a holding means, a storage flow path 27 that stores the plate spring 22, and the pressure chamber 15. A valve body 23 that moves between a valve closing position for blocking the introduction of ink and a valve opening position for introducing ink into the pressure chamber 15, and the valve body 23 and the valve body 23 when the valve body 23 is located at the valve closing position. An O-ring 24 serving as a sealing portion that seals the introduction port 17 in close contact with the outer peripheral portion of the port 17 is provided.

  The accommodation chamber 21 is a circular hole in which the lower side of the introduction port 17 is expanded. On the inner peripheral surface 21 a of the storage chamber 21, a storage flow path 27 formed so as to extend in parallel with the operation lever 13 is opened. The accommodation flow path 27 communicates with a communication path 25 that is an ink flow path formed in the carriage body 11 on the opposite side of the valve body 23, that is, on the fixed end side of the leaf spring 22, and the communication path 25 is connected to the carriage body. 11 is connected to a connection port 26 provided on one side surface.

  The connection port 26 connects the carriage body 11 and the ink cartridges C1 and C2 as fluid supply means. When ink is pumped from the ink cartridges C1 and C2, the ink is sequentially fed into the connection port 26, the communication path 25, the storage flow path 27, and the storage chamber 21, respectively. The carriage body 11 is formed with the opposing quantity of pressure reducing valves 20, that is, six communication passages 25, connection ports 26, an accommodation passage 27, and an accommodation chamber 21.

  In the accommodation flow path 27, the leaf spring 22 is accommodated in a cantilever shape with one end 22a fixed thereto. As the leaf spring 22, in this example, a stainless steel plate formed in an elongated strip shape is used. And the valve body 23 is arrange | positioned between the upper surface of the front-end | tip part at the free end side of the said leaf | plate spring 22, and the ceiling surface 21c (outer peripheral part of the inlet 17) of the storage chamber 21. As shown in FIG.

  The valve body 23 is formed on the flange 23b accommodated in the storage chamber 21 so as to be vertically movable, a cylindrical upper shaft portion 23a formed on the upper surface of the flange 23b, and a lower surface of the flange 23b. And a substantially hemispherical lower shaft portion 23e.

  The upper shaft portion 23 a of the valve body 23 is formed such that its outer diameter is smaller than the inner diameter of the introduction port 17, and its upper end is inserted through the introduction port 17. Then, the ink in the storage chamber 21 is introduced into the pressure chamber 15 through the gap between the upper shaft portion 23 a and the introduction port 17.

  The flange 23b of the valve body 23 is formed in a substantially square shape in a plan view direction. The flange portion 23 b is formed to extend in a direction perpendicular to the upper shaft portion 23 a and is disposed between the upper surface of the leaf spring 22 and the ceiling surface 21 c of the storage chamber 21. On the outer peripheral surface of the flange 23b, a slidable contact surface 23c slidably contacting the inner peripheral surface 21a of the storage chamber 21 and a part of the slidable contact surface 23c are notched at equal angular intervals to be separated from the inner peripheral surface 21a. And a notch portion 23d formed.

  The flange 23b of the valve body 23 receives the elastic force of the leaf spring 22 that contacts the lower flange 23e, and always biases the valve body 23 toward the ceiling surface 21c. At this time, the flange portion 23b allows the sliding contact surface 23c to slide in contact with the inner peripheral surface 21a and allows only the movement of the valve body 23 along the vertical direction of the inner peripheral surface 21a. In the valve body 23, the ink below the flange portion 23b is introduced to the introduction port 17 side through a gap between the notch portion 23d and the inner peripheral surface 21a.

  An O-ring 24 is arranged and fixed on the upper surface (surface on the ceiling surface 21c side) of the flange 23b of the valve body 23. The O-ring 24 is set closer to the center of the upper shaft portion 23a than the notch portion 23d and has a larger diameter than the upper shaft portion 23a. A locking step portion 23f is formed on the upper surface of the flange 23b of the valve body 23 for locking the O-ring 24 in a state where the O-ring 24 is positioned at a predetermined position.

  Further, the lower shaft portion 23e of the valve body 23 is formed in a substantially hemispherical shape at the center of the lower surface of the flange portion 23b. And the lower top part which is the center CT of the said lower collar part 23e is arrange | positioned so that it may become the center of the O-ring 24 positioned by the latching step part 23f. Thus, the O-ring 24 is positioned by the locking step portion 23f formed on the valve body 23, and the lower top portion, which is the center of the lower shaft portion 23e formed on the valve body 23, is supported by the leaf spring 22. Therefore, the support point by the leaf spring 22 can be accurately set to the center position with respect to the O-ring 24 as the sealing portion.

  As a result, the lower shaft portion 23e is formed on the side of the valve body 23 that is supported by the leaf spring 22, and is in contact with the leaf spring 22 at a position substantially at the center of the O-ring 24 as the sealing portion. Functions as a contact protrusion. The leaf spring 22 urges the valve body 23 toward the valve closing position at a position substantially at the center of the O-ring 24 in the valve body 23.

  On the other hand, in the accommodating flow path 27 in which the leaf spring 22 is accommodated, the valve element 23 is moved from the valve closing position to the valve opening position between the surface of the leaf spring 22 opposite to the valve element 23 and the flow path wall surface. A lower space 27b is formed as a deformation allowable space of the leaf spring 22 that can be displaced.

  Further, in the accommodation flow path 27 in which the leaf spring 22 is accommodated, there is a gap between the face of the leaf spring 22 on the valve body 23 side and the flow path wall surface while the valve body 23 is supported at the closed position. An upper space 27a is formed so as to be formed.

  Further, in the accommodation flow path 27 in which the leaf spring 22 is accommodated, elongated ink circulation spaces 27 c along the longitudinal direction of the leaf spring 22 are secured on both sides of the leaf spring 22. Thereby, the reciprocating motion of the valve body 23 can be made smoother without causing any trouble in the flow of ink in the accommodating flow path 27 and the deformation operation of the leaf spring 22.

  The valve body 23 is supported by a leaf spring 22 provided in the accommodating flow path 27 communicating with the introduction port 17, whereby the pressure in the pressure chamber 15 is reduced to a predetermined pressure. Until the valve is closed.

  That is, in the valve body 23 urged toward the ceiling surface 21 c by the leaf spring 22, the flange portion 23 b and the ceiling surface 21 c are in close contact with the O-ring 24 unless subjected to stress against the elastic force of the leaf spring 22. It is held in the position (valve closing position). In other words, the valve element 23 is held in the valve closing position and blocks the introduction of ink into the pressure chamber 15 unless it receives a stress against the elastic force of the leaf spring 22. At this time, the valve body 23 held at the valve closing position always projects the upper end of the upper shaft portion 23 a from the bottom surface of the groove-like flow path 12 into the upper pressure chamber 15.

  When the introduction of the ink is blocked by the valve body 23, the pressure in the pressure chamber 15 is set to a predetermined pressure (for example, the minimum pressure at which the recording head 30 does not cause the ink ejection failure) due to the consumption of the ink by the recording head 30. ) Until the pressure is reduced. When the pressure in the pressure chamber 15 is reduced to a predetermined pressure, the pressure receiving portion 14a is displaced toward the lower side of the pressure chamber 15 and moves down the pressing portion 13b. At this time, the pressing portion 13b that moves downward boosts the pressing force of the pressing portion 13b that faces the upper shaft portion 23a by the principle of the lever that uses the tip of the pressing portion 13b as a power point.

  And the press part 13b facing the upper shaft part 23a moves down the upper end of the upper shaft part 23a with the operating force which doubled the pressing force. That is, when the pressure in the pressure chamber 15 is reduced to a predetermined pressure, the valve body 23 located at the valve closing position is displaced to a position (valve opening position) that separates the O-ring 24 from the ceiling surface 21c. Ink is allowed to be introduced into the pressure chamber 15.

  When ink is introduced into the pressure chamber 15, the pressure in the pressure chamber 15 is increased from a predetermined pressure. When the pressure in the pressure chamber 15 is increased, the pressure receiving portion 14a is displaced toward the upper side of the pressure chamber 15 and moves up the pressing portion 13b. Then, the pressing portion 13b facing the upper shaft portion 23a is separated from the upper end of the upper shaft portion 23a to release the operating force. In other words, when ink is introduced into the pressure chamber 15, the valve body 23 located at the valve opening position is again displaced to the valve closing position, thereby blocking the introduction of ink into the pressure chamber 15.

  At this time, the leaf spring 22 supports the valve body 23 at the lower top portion (that is, the center CT) of the lower shaft portion 23e, which is the center of the O-ring 24, and biases it toward the ceiling surface 21c. That is, the elastic force of the leaf spring 22 is applied to the valve body 23 located at the valve closing position with the center side (in this example, the center CT) from the O-ring 24 serving as a fulcrum. As a result, the valve body 23 brings its flange 23 b into close contact with the entire circumference of the O-ring 24.

  Ink of each color that is pressure-fed from the ink packs B, C, M, YL, LC, and LM of the first cartridge C1 and the second cartridge C2 to the carriage 10 is connected to the connection port 26 and the communication path provided in the carriage 10, respectively. 25, supplied to the storage chamber 21. The ink supplied to the storage chamber 21 is stored in the storage chamber 21 until the pressure reducing valve 20 is opened, that is, the pressure in the pressure chamber 15 is a predetermined pressure.

  When the recording head 30 consumes ink by driving the piezo element 62, the pressure in the pressure chamber 15 is reduced to a predetermined pressure, and the pressing portion 13b moves down the upper end of the upper shaft portion 23a. As a result, the valve body 23 moves to the valve opening position, and the ink supplied into the storage chamber 21 is introduced into the pressure chamber 15. When ink is introduced into the pressure chamber 15, the pressure in the pressure chamber 15 is increased, and the pressure receiving portion 14a moves up the pressing portion 13b. When the pressing portion 13b moves upward, the valve body 23 is again displaced to the valve closing position, shuts off the introduction of ink into the pressure chamber 15, and stops the pressure increase in the pressure chamber 15.

  In this way, the pressure reducing valve 20 reduces the pressure of ink supplied from the carriage 10 to the recording head 30 to a predetermined pressure by reciprocation between the valve closing position and the valve opening position of the valve body 23, and ejects ink. Avoid excessive boosting that can cause failures.

  According to the present embodiment, the valve body 23 held at the valve closing position by the leaf spring 22 is in close contact with the O-ring 24 that is in close contact with the outer peripheral portion of the introduction port 17 to block the introduction of ink into the pressure chamber 15. To do. When the ink in the pressure chamber 15 is led out and the pressure in the pressure chamber 15 becomes lower than a predetermined pressure, the displacement means is displaced to move the valve body 23 to the valve open position. The valve body 23 that moves between the valve closing position and the valve opening position is urged toward the valve closing position by the leaf spring 22 provided in the accommodating flow path 27 that communicates with the introduction port 17. In addition, since the leaf spring 22 having a very simple shape is present in the flow path, bubbles are easily removed during the initial ink filling, the amount of ink consumed for the initial filling is reduced, and the probability of missing dots is achieved. Can be greatly reduced.

  Thus, instead of using a conical coil spring as in the prior art, the valve spring 23 is supported by the leaf spring 22 provided in the accommodation flow path 27, so that the urging force at the center of the O-ring 24 is increased. By doing so, the valve body 23 and the outer peripheral portion of the introduction port 17 are securely brought into close contact with the O-ring 24, the sealing by the O-ring 24 is made uniform, and the sealing performance is ensured and the pressure is adjusted. It is possible to improve the stability and reliability of the pressure adjustment by greatly reducing the variation of the pressure. In addition, the leaf spring is not only easily downsized, but accuracy can be ensured even if the leaf spring is downsized, and the cost is not increased significantly. In addition, the ease of assembly is greatly improved, and the time required for assembly can be greatly reduced.

  Further, the leaf spring 22 biases the valve body 23 toward the valve closing position at a position substantially at the center of the O-ring 24 in the valve body 23, so that the valve body 23 is substantially at the center of the O-ring 24. By urging at the position, the outer peripheral portion of the inlet 17 is securely brought into close contact with the O-ring 24, the sealing by the O-ring 24 is made uniform to ensure the sealing performance, and the variation in pressure adjustment is greatly reduced. Thus, the stability and reliability of pressure adjustment can be improved.

  Further, a lower shaft portion 23e is formed on the side supported by the leaf spring of the valve body 23 as a contact protrusion that contacts the leaf spring 22 at a position substantially at the center of the O-ring 24. The contact between the contact protrusion and the leaf spring 22 enables the valve body 23 to be urged at the substantial center position of the O-ring 24, so that the valve body 23 and the outer peripheral portion of the introduction port 17 are securely attached to the O-ring 24. It is possible to make the sealing by the O-ring 24 uniform to ensure the sealing performance, and to greatly reduce the pressure adjustment variation, thereby improving the stability and reliability of the pressure adjustment.

  Further, in the accommodating flow path 27 in which the leaf spring 22 is accommodated, the valve body 23 is moved from the valve closing position to the valve opening position between the surface of the leaf spring 22 opposite to the valve element 23 and the flow path wall surface. Since the lower space 27b is formed as a deformation-permitting space for the leaf spring 22 that can be displaced, the leaf spring 22 is easily deformed in the lower space 27b by the displacement of the displacing means. Can be moved from the valve closing position to the valve opening position, and the pressure can be adjusted reliably and stably.

  Further, in the flow path in which the leaf spring 22 is accommodated, a gap is formed between the face of the leaf spring 22 on the valve body 23 side and the flow path wall surface with the valve body 23 supported at the valve closing position. Thus, when the leaf spring 22 is deformed by the displacement of the displacement means, the leaf spring 22 due to the surface tension of the ink flowing into the upper space 27a, which is the gap between the flow path wall surface and the leaf spring 22, is formed. The deformation resistance of becomes smaller. For this reason, pressure adjustment can be performed reliably and stably.

  Further, since the sealing portion is an O-ring 24 formed on the valve body 23 and disposed on the introduction port 17 side of the flange portion 23b that closes the introduction port 17, the introduction portion 17 of the flange portion 23b The leaf spring 22 that abuts on the opposite side urges the flange 23b toward the introduction port 17 so that the O-ring 24 disposed on the introduction port 17 side of the flange 23b closely contacts the outer periphery of the introduction port 17. Accordingly, the flange portion 23b can be urged toward the introduction port 17 with the O-ring 24 and one end of the leaf spring 22 contacting the inner side of the O-ring 24 as a fulcrum and a power point, respectively. As a result, the flange portion 23b and the outer peripheral portion of the introduction port 17 can be reliably brought into close contact with the O-ring 24, respectively. Therefore, by disposing the valve body 23 at the valve closing position, the introduction of the fluid into the pressure chamber 15 can be reliably blocked, and as a result, the stability of the pressure adjustment operation by the pressure reducing valve 20 can be improved.

  The flange 23b of the valve body 23 includes a sliding contact surface 23c that slides along the inner peripheral surface 21a of the storage chamber 21 serving as a valve body storage flow path for storing the valve body 23, and the storage chamber 21. Since the notch portion 23d that forms a gap with the inner peripheral surface 21a is provided, the flange portion 23b can be guided along the inner peripheral surface of the valve body accommodating flow path, and displacement of the valve body 23 is avoided. can do. Furthermore, the sliding load of the valve body 23 can be reduced, and the ink flow path resistance can be reduced. As a result, the reciprocation of the valve body 23 can be made smoother.

  The displacing means includes a flexible film 14 that forms a part of the pressure chamber 15 and is displaced inward of the pressure chamber 15 when the pressure in the pressure chamber 15 becomes lower than a predetermined pressure. Since it is configured to include an operating lever 13 that displaces the valve body 23 to the valve opening position against the biasing force of the leaf spring 22 by an operating force obtained by multiplying the displacement force due to the displacement of the flexible film 14. The actuating lever 13 displaces the valve element 23 to the valve opening position by the actuating force obtained by multiplying the displacement force of the flexible film 14. Therefore, the pressure receiving area of the flexible film 14 can be reduced, and a small and lightweight pressure reducing valve 20 with improved stability of the pressure adjusting operation can be realized.

  In addition, this invention is not limited to said each embodiment, It is the meaning including the following modifications.

  In the above embodiment, the material of the leaf spring 22 is made of stainless steel. However, the material is not limited to this, and the material is not limited as long as the plate-like urging member can be formed.

  In the above embodiment, the valve body 23 is formed with the substantially semispherical lower shaft portion 23e, and the valve body 23 is supported by the lower apex of the substantially hemispherical lower shaft portion 23e. 23e may be formed, or at least the tip of the cylindrical lower shaft portion 23e may be hemispherical or conical.

  In the above embodiment, four notches 23d are formed at equiangular intervals. However, for example, one may be provided, and the valve body 23 only needs to have a surface spaced from the inner peripheral surface 21a.

  In the above embodiment, the notch 23d is formed on the outer peripheral surface of the flange 23b. However, for example, a notch may be provided along the vertical direction of the inner peripheral surface 21a, and the inner peripheral surface 21a and the flange 23b What is necessary is just to form the clearance gap used as the ink flow path between them.

  In the above-described embodiment, an example in which the gear pump GP is used as a pump has been described. However, various pumps such as a tube pump, a piston pump, and a diaphragm pump can be employed in addition to the gear pump GP.

  In the above embodiment, the pressure generating mechanism that uses the piezo element 62 as the pressure generating mechanism for ejecting ink from the nozzle 60 of the recording head 30 has been described. However, the ink is ejected at a pressure generated by generating bubbles by the heating element. Can also be applied.

  Moreover, the fluid targeted by the fluid ejecting apparatus of the present invention is not limited to the above-described fluid such as ink, but targets various fluids such as metal paste, powder, liquid crystal, and other high viscosity materials. It is the purpose. As a typical example of the fluid ejecting apparatus, there is an ink jet recording apparatus provided with the ink jet recording head for image recording as described above, but the fluid supply apparatus of the present invention is, for example, Devices equipped with color material ejection heads used in the manufacture of color filters such as liquid crystal displays, devices equipped with electrode material (conductive paste) ejection heads used in electrode formation such as organic EL displays and surface emitting displays (FEDs), bio The present invention can be applied to various fluid ejecting apparatuses such as an apparatus having a bio-organic matter ejecting head used for chip manufacture and an apparatus having a sample ejecting head as a precision pipette.

1 is a perspective view showing an ink jet printer that embodies the present invention. Explanatory drawing explaining the ink flow path of the said ink jet type printer. 1 is a side sectional view showing a carriage embodying the present invention. The principal part top view which shows the said carriage. The principal part side sectional view which shows the pressure-reduction valve which actualized this invention. FIG. 3 is a bottom sectional view showing the carriage. The principal part bottom sectional view showing the above-mentioned decompression valve.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Carriage, 11 Carriage body, 12 Groove flow path, 13 Actuation lever, 13a Support part, 13b Press part, 14 Film, 14a Pressure receiving part, 15 Pressure chamber, 16 Protection plate, 16a Recessed part, 17 Inlet, 18 Outlet , 19 Atmospheric opening, 20 Pressure reducing valve, 21 Accommodating chamber, 21a Inner circumferential surface, 21c Ceiling surface, 22 Leaf spring, 22a One end, 23 Valve body, 23a Upper shaft portion, 23b Saddle portion, 23c Sliding surface, 23d Notch portion, 23e lower shaft portion, 23f locking step portion, 24 O-ring, 25 communication path, 26 connection port, 27 receiving flow path, 27a upper space, 27b lower space, 27c distribution space, 30 recording head, 50 printer , 51 frame, 52 paper feed tray, 53 paper discharge tray, 54 guide member, 55 ink absorber, 56 opening device, 57 platen, 9 Nozzle forming surface, 60 Fluid injection nozzle (nozzle), 61 Diaphragm, 62 Piezo element, 63 Cap holder, 64 Cap, 65 Absorbent, 66a, 66b Through hole, 67 Adjusting device, B, C, M, YL, LC, LM ink pack, C1 first cartridge, C2 second cartridge, G1, G2 gear, GP gear pump, T1, T2, T3, T4, T5, T6, T7 tube, V1 release valve, X main scanning direction, Y sub Scan direction

Claims (5)

A fluid supply apparatus having a pressure reducing valve for reducing a pressure chamber that stores fluid introduced from an inlet and leads to a outlet to a predetermined pressure,
The pressure reducing valve includes a valve body that moves between a valve closing position for blocking the introduction of fluid into the pressure chamber and a valve opening position for introducing fluid into the pressure chamber, and the pressure in the pressure chamber is reduced to the predetermined pressure. Then, the displacement means for displacing the valve body from the valve closing position to the valve opening position, and when the valve body is located at the valve closing position, the introduction port is sealed in close contact with the outer periphery of the valve body and the introduction port. Having a sealing part,
The valve body is supported by a plate-like urging member provided in the flow path communicating with the introduction port, so that the valve body is held in the closed position until the pressure in the pressure chamber is reduced to the predetermined pressure. A fluid supply device.   The fluid supply device according to claim 1, wherein the plate-like urging member urges the valve body toward the valve closing position at a position substantially at the center of the sealing portion of the valve body.   3. The fluid according to claim 2, wherein a contact protrusion is formed on the side of the valve body that is supported by the plate-like urging member so as to come into contact with the plate-like urging member at a position substantially at the center of the sealing portion. Feeding device.   In the flow path in which the plate-shaped urging member is accommodated, the valve element is displaced from the valve-closing position to the valve-opening position between the surface of the plate-shaped urging member opposite to the valve element and the wall surface of the flow path. The fluid supply apparatus according to any one of claims 1 to 3, wherein a deformable space for the plate-shaped urging member as much as possible is formed.   The flow path in which the plate-like urging member is accommodated is formed such that a gap is formed between the valve-side surface of the plate-like urging member and the flow wall surface in a state where the valve body is supported at the valve closing position. The fluid supply device according to any one of claims 1 to 4, wherein the fluid supply device is formed.

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