JP2008200996A - Valve device, fluid feeder, and fluid ejection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve device which can prevent the dispersion of operating pressure due to difference in individual valve bodies, the dispersion being caused by fluctuation of a load applied to the valve body attributable to a change of a diaphragm deflecting direction, and to provide a fluid feeder, and a fluid ejection device. <P>SOLUTION: According to the structure of a valve unit 21, a valve hole 52 is formed in a partition 51 partitioning an ink feeding chamber 56 from a pressure chamber 43. A shaft portion 57b of the valve body 57 in the ink feeding chamber 56, energized toward the pressure chamber 43 by a compressive spring 59, is inserted into the valve hole 52, and abutted on a pressure receiver 65 secured to the internal surface of the diaphragm 42a. Further the pressure receiver 65 is energized outward by a negative pressure holding spring 66 arranged in the pressure chamber 43. In the state that the pressure chamber 43 is pressurized by the operating pressure, when the valve unit is closed, i.e. when a projection 60a of a sealing member 60 covering a plate portion 57a of the valve body 57 abuts on a valve seat 61, the diaphragm 42a is recessed from a welding position toward the pressure chamber 43 in the side surface of a frame 40 of a film member 42. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a valve device that includes a diaphragm and opens and closes based on a pressure difference (differential pressure) on both sides of the diaphragm, and a fluid supply device.

  Conventionally, as this type of valve device, for example, Patent Document 1 discloses a back pressure regulator, and the back pressure regulator includes a diaphragm, a diaphragm piston, a lever, a valve seat, and a nozzle. . When the back pressure in the print head falls below a predetermined value, a force is applied to the diaphragm piston, and the lever rotates. The valve seat provided on the lever is separated from the nozzle by the rotation of the lever, and the ink flows into the print head. Therefore, the ink is supplied to the print head at a uniform pressure by the back pressure regulator regardless of the pressure fluctuation in the supply tube, and the print quality can be improved.

  However, since the back pressure regulator has a plurality of parts interposed between the diaphragm and the valve seat, there is a problem that the configuration is complicated and it is difficult to reduce the size and power transmission loss is likely to occur. there were.

As a configuration that can solve this problem, for example, a valve device described in Patent Document 2 is known. That is, the valve device described in Patent Document 2 is a valve unit for ink supply provided on the carriage side in an ink jet printer, and receives ink from an ink cartridge disposed on the main body side of the ink jet printer. The pressure was adjusted and supplied to the recording head and had a self-sealing function. The valve unit includes an ink supply chamber and a pressure chamber, and ink supplied from the ink cartridge is supplied from the ink supply chamber to the recording head via the pressure chamber. A movable valve biased by a spring toward the pressure chamber side (valve closing direction) is provided between the ink supply chamber and the pressure chamber, and the ink supply chamber communicates with the pressure chamber by opening and closing the movable valve. It is configured to be out of communication. A pressure receiving plate provided on a film member (diaphragm) constituting a part of the pressure chamber is displaced due to a decrease in the amount of ink in the pressure chamber accompanying ink ejection of the recording head, and the displacement is directly applied to the movable valve. The movable valve is configured to operate by transmission.
Japanese Patent Laid-Open No. 9-11488 Japanese Unexamined Patent Application Publication No. 2004-142405 (for example, FIGS. 25 to 27, etc.)

  However, in the valve unit for supplying ink described in Patent Document 2, if the spring is weakened in response to a request to reduce the absolute value of the operating pressure (ink pressure in the pressure chamber), a part of the pressure chamber is formed. The influence of the reaction force of the film (diaphragm) came to appear, and there was a problem that the operating pressure greatly varied depending on the film posture.

  That is, if the angle at which the rod member of the movable valve hits the portion corresponding to the pressure receiving plate in the film member varies, the force transmitted from the film member to the rod member varies, and the fluid pressure variation in the pressure chamber when the valve unit opens and closes. This causes the problem that the operating pressure varies.

  By the way, in the valve unit closed state, the diaphragm is substantially flush with the side surface of the unit case (the surface on which the film member constituting the diaphragm is thermally welded). However, for example, the position of the diaphragm when it is at the operating pressure in the valve-closed state is outside the position of the welded part (air Side). In this case, when the diaphragm (film member) changes from a convex state inflating to the atmosphere side to a concave state to the pressure chamber side, the reaction force (film reaction force) to restore the diaphragm to its original shape without bending. The direction of the valve changes from the direction of the valve opening direction that works when the diaphragm expands outward to the direction of the valve closing direction that works when the diaphragm is recessed toward the pressure chamber. For this reason, the load applied to the valve body fluctuates before and after the direction in which the film reaction force acts is changed, and this causes variations in operating pressure due to individual differences. This variation in operating pressure due to individual differences appears as a variation in ink pressure within the recording head, resulting in variations in the mass of ink droplets ejected from the nozzles when an ejection drive element such as a piezoelectric vibrator is driven. There is a problem of making it.

  The present invention has been made in view of the above problems, and its purpose is to suppress variations in operating pressure due to individual differences due to fluctuations in the load acting on the valve body due to a change in the direction in which the diaphragm bends. Another object is to provide a valve device, a fluid supply device, and a liquid ejecting device.

  The present invention is a pressure adjusting valve device provided in the middle of a flow path for supplying fluid from a fluid supply source to a fluid ejecting means, the fluid supply chamber communicating with the flow path on the upstream side, and the flow path A pressure chamber that communicates with the downstream side of the pressure chamber, a diaphragm that constitutes a part of the wall surface of the pressure chamber and is deflected by a pressure difference between the inside and the outside of the pressure chamber, a pressure receiving member provided in the diaphragm, Based on the fluid pressure in the pressure chamber when the fluid is reduced, the valve opening direction is increased based on the force in the valve opening direction acting on the pressure receiving member, and the fluid flows into the pressure chamber from the fluid supply chamber by the valve opening. Valve means for closing the valve when the force in the valve opening direction acting on the pressure receiving member is weakened based on the fluid pressure in the pressure chamber at the time, and reducing the fluid pressure in the fluid supply chamber by opening and closing the valve means To maintain the pressure chamber at a predetermined operating pressure. The valve means is configured so that the diaphragm is held in a recessed state toward the pressure chamber even when the pressure chamber is in the operating pressure and is changed from the open state to the closed state. It is a summary.

  According to this, even when the valve means changes from the valve open state to the valve close state in a state where the pressure chamber of the valve device is at the operating pressure, the diaphragm is in a bent state in which it is recessed toward the pressure chamber. For this reason, after that, the fluid is ejected by the fluid ejecting means, the fluid in the pressure chamber is reduced, the pressure receiving member is displaced in the valve opening direction, and the valve means is changed from the valve closing state to the valve opening state. The direction of the dent is held in a state of being recessed toward the pressure chamber. That is, the direction of the diaphragm reaction force acting on the pressure receiving member does not change in the middle, and the diaphragm reaction force always works in the same direction. This is true even when there is a variation due to individual differences in the valve device, because the diaphragm is in a state of being depressed toward the pressure chamber side in anticipation of variation when the valve is closed. For this reason, variations due to individual differences in the operating force for opening and closing the valve means (the sum of forces such as the force acting on the pressure receiving member based on the fluid pressure in the pressure chamber and the reaction force of the diaphragm) are unlikely to occur. As a result, variations in operating pressure due to individual differences among valve devices can be suppressed.

  In the valve device of the present invention, the valve means includes a valve body partially accommodated in the fluid supply chamber, and an urging means for urging the valve body in a valve closing direction, and the valve body is the fluid. It is preferable that a shaft portion inserted through a valve hole communicating with the supply chamber and the pressure chamber is provided, and the shaft portion is in direct or indirect contact with the pressure receiving member.

  According to this, the valve body is urged in the valve closing direction, and the force acting on the pressure receiving member based on the fluid pressure in the pressure chamber is controlled via the shaft portion that is in direct or indirect contact with the pressure receiving member. Transmitted to the body. When the fluid in the pressure chamber decreases due to consumption or the like and the force in the valve opening direction acting on the pressure receiving member increases, the valve body that receives the force in the valve opening direction from the pressure receiving member resists the biasing force of the biasing means. And the valve device is opened. When the valve device opens, the fluid flows from the fluid supply chamber to the pressure chamber.

  In the valve device of the present invention, the pressure receiving member is fixed to the inner surface of the diaphragm on the pressure chamber side, and the shaft portion of the valve body is in contact with the pressure receiving member when the pressure chamber is at an operating pressure. It is preferable. According to this, the shaft portion of the valve body is in direct contact with the pressure receiving member. For this reason, a diaphragm is hard to be damaged compared with the structure which the axial part is contact | abutting indirectly to the pressure receiving member via the diaphragm.

The valve device according to the present invention preferably includes a fluid pressure setting spring provided in the pressure chamber and biasing the pressure receiving member in a valve closing direction or a valve opening direction of the valve means.
According to this, when the biasing force of the fluid pressure setting spring is in the valve closing direction, it is necessary to move against the biasing force of the fluid pressure setting spring when the pressure receiving member is displaced in the valve opening direction. The fluid pressure (operating pressure) of the pressure chamber can be set to the lower side by the amount corresponding to the urging force of the fluid pressure setting spring. On the other hand, when the biasing force of the fluid pressure setting spring is in the valve opening direction, the biasing force of the fluid pressure setting spring promotes the displacement of the pressure receiving member in the valve opening direction. The fluid pressure (working pressure) of the pressure chamber can be set on the higher side. Therefore, the fluid pressure (operating pressure) in the pressure chamber can be adjusted by the presence of the fluid pressure setting spring.

  In the valve device of the present invention, the fluid pressure setting spring is a coil spring, and the pressure receiving member has a first cylindrical portion that supports one end of the fluid pressure setting spring, and the fluid supply chamber, the pressure chamber, A second cylindrical portion that supports one end portion of the fluid pressure setting spring is formed on the surface of the partition wall that partitions the fluid chamber so as to surround the valve hole. The valve device according to claim 3, wherein a notch penetrating in a radial direction is formed.

  According to this, when the diaphragm is displaced to the pressure chamber side and the valve device is opened, the gap between the first tubular portion and the second tubular portion that are close to each other as the fluid pressure setting spring is compressed. Even if becomes narrower, the fluid flowing in from the fluid supply chamber through the valve hole can be sent to the outer peripheral side of the pressure chamber through the notch of the second cylindrical portion.

  The present invention is a fluid supply apparatus according to the above invention, which is provided on a fluid supply source, fluid ejection means for ejecting fluid, and a flow path for supplying fluid from the fluid supply source to the fluid ejection means. The gist is provided with a valve device. According to this fluid supply apparatus, the effect of the valve apparatus of the said invention can be acquired.

  The gist of the present invention is a fluid ejecting apparatus including the fluid supply apparatus according to the present invention. According to this fluid ejecting apparatus, it is possible to obtain the same effect as that of the fluid supply apparatus of the present invention.

Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS.
FIG. 1 is a plan view of the ink jet recording apparatus with the outer case removed.
An ink jet recording apparatus (hereinafter simply referred to as a recording apparatus 11) as a fluid ejecting apparatus has a main body case 12 formed of a substantially rectangular parallelepiped box having an upper side (the front side in FIG. 1) opened. A platen 13 is arranged in the main body case 12 so as to extend in the main scanning direction (left-right direction in FIG. 1), and a recording medium (not shown) as a target is supported by the platen 13 in a paper It is conveyed in the sub-scanning direction (vertical direction in FIG. 1) by a feeding means (not shown).

  Further, a rod-shaped guide shaft 14 is installed in the main body case 12 so as to extend in parallel with the platen 13. A carriage 15 is supported on the guide shaft 14 so as to be reciprocally movable along the axial direction. The carriage 15 is fixed at a timing belt 17 wound around a pair of pulleys 16a and 16b pivotally supported at the rear part (upper part in FIG. 1) of the main body case 12 and a back side (upper part in FIG. 1). ing. In FIG. 1, the carriage 15 reciprocates along the main scanning direction via a timing belt 17 that rotates forward and backward when a carriage motor 18 disposed near the right end of the back surface of the main body case 12 is driven forward and backward. .

  A recording head 20 serving as a fluid ejecting unit that ejects ink serving as a fluid is provided below the carriage 15. A plurality of pressure adjusting valve units 21 are mounted on the carriage 15. Each valve unit 21 adjusts (decreases) the pressure of black, yellow, magenta, and cyan inks and supplies them to the recording head 20. At the time of printing, based on the image data, a printing operation for ejecting ink from the nozzles of the recording head 20 while moving the carriage 15 in the main scanning direction (left-right direction in FIG. 1) and a recording medium (not shown) by a paper feeding means (not shown). The recording medium is printed by alternately performing a paper feeding operation for moving the recording paper) in the sub-scanning direction.

  The cartridge holder 24 provided at one end (the right end in FIG. 1) of the main body case 12 is detachably loaded with four ink supply sources (fluid storage means) corresponding to the ink color. ing. Each cartridge holder 24 is connected to each valve unit 21 through an ink supply tube 35.

  As shown in FIG. 1, a pressurizing pump 25 is provided above the loading position of the ink cartridge 23 while being supported by the main body case 12. The pressurizing pump 25 can suck the atmosphere and discharge it as pressurized air. The discharged pressurized air is supplied to the atmosphere release valve 38 through the pressure detector 36 through the pressure tube 37. The

  The pressure detector 36 detects the pressure of the air supplied from the pressurizing pump 25. Based on the detected pressure of the pressure detector 36, the driving of the pressurizing pump 25 is controlled. The air release valve 38 is connected to the cartridge holder 24 through four air supply tubes 39, and pressurized air is introduced into the ink cartridge 23. The air release valve 38 is a valve that is switched between a valve open state that opens the internal chamber to the atmosphere and a valve closed state that blocks communication with the air in the chamber. When the pressurizing pump 25 is driven, The valve is closed.

  FIG. 2 shows a basic configuration of an ink supply system in the recording apparatus. Here, the ink supply system shown in FIG. 2 is an air pressure supply type. FIG. 2 shows only the ink supply system for one color.

  The pressurizing pump 25 includes an electric motor 25a and a pump 25b. On the pressurizing tube 37 that connects the discharge port of the pump 25b and the ink cartridge 23, the pressure detector 36 and the air release valve 38 are provided in series.

  The ink cartridge 23 has an outer case 23a formed in an airtight state, and ink is sealed and an ink pack 23b made of a flexible material is accommodated in the outer case 23a. When the ink cartridge 23 is loaded, the pressurizing tube 37 is configured to communicate with the air chamber 34 between the outer case 23a and the ink pack 23b, and the pressurized air sent from the pressurizing pump 25 is The air chamber 34 is introduced.

  As shown in FIG. 2, the ink outlet 23 c of the ink pack 23 b is connected to the ink supply tube 35 when the ink cartridge 23 is loaded. The ink pack 23 b is pressurized from outside by the pressurized air introduced into the air chamber 34 in the ink cartridge 23, and the pressurized ink is supplied from the ink pack 23 b to the valve unit 21 through the ink supply tube 35. The pressurized ink supplied to the valve unit 21 is reduced to a predetermined operating pressure (negative pressure) slightly lower than the atmospheric pressure, and the ink reduced to the operating pressure is supplied to the recording head 20. The recording head 20 includes an ink chamber and an ejection drive element (both not shown) for each nozzle, and the ejection force (ejection pressure) when the ejection drive element is driven reaches the ink in the ink chamber. Ink is ejected from the nozzles. Note that the ejection drive element uses a piezoelectric vibration element or electrostatic drive element that ejects ink droplets with vibration-induced ejection pressure, or the growth / contraction of bubbles generated by boiling the film locally by applying heat to the ink. Thus, an electrothermal conversion element that ejects ink droplets can be employed. Further, the ink supply system of the water head difference type that supplies ink from the ink cartridge 23 by the water head difference can be adopted. The ink supply system constitutes a fluid supply device.

FIG. 3 is a perspective view showing the valve unit 21 and the recording head 20.
As shown in FIG. 3, the four valve units 21 are mounted on the upper part of a head support 46 (which constitutes a part of the carriage 15) that supports the recording head 20 at the lower part. The valve unit 21 includes a synthetic resin frame 40 having a flat shape, and a tube 35 is connected to a connecting pipe portion 41 provided at one end thereof. A flexible film member 42 is thermally welded to one side surface of the frame 40, and a pressure chamber 43 and an ink outlet path 44 are formed inside the valve unit 21 so as to form a part of the wall surface with the film member 42. Is partitioned.

  The film member 42 is made of a material that is soft so that a negative pressure state can be sensed efficiently, has no chemical effect on the ink, and has a low moisture permeability and gas permeability such as oxygen and nitrogen. used. For example, a high-density polyethylene film or a polypropylene (PP) film may be laminated with a nylon film coated with vinylidene chloride (saran). Moreover, you may use a polyethylene terephthalate (PET) etc. as another material. In addition to heat welding, the film member 42 may be fixed using vibration welding or an adhesive.

  The pressure chamber 43 is a reservoir chamber for the ink that has been decompressed in the valve unit 21, and the ink having the decompressed operating pressure passes downward from the pressure chamber 43 to the lower right side of the valve unit 21 in FIG. It is led out to the connection part 45 of the substantially cylindrical shape protruding to A plurality of annular connected portions 47 (four in this example) are provided on the upper portion of the head support 46, and the valve unit 21 is connected to the corresponding connecting portion 45 and the connected portion 47 of ink color. In the state, it is attached to the head support 46. The ink decompressed by the valve unit 21 is sent to an ink flow path (not shown) in the head support 46 via the connection between the connecting portion 45 and the connected portion 47, and the recording head 20 is supplied from this ink flow path. The ink is supplied to the ink chamber for each nozzle through the ink flow path. The ink supply tube 35 and the ink flow path in the head support 46 constitute a flow path that connects the fluid supply source and the fluid ejecting means.

  A diaphragm 42 a is configured by a part of the film member 42 that constitutes a part of the wall surface of the pressure chamber 43. The valve unit 21 incorporates a differential pressure type pressure regulating valve 21A (pressure reducing valve) having a diaphragm 42a as a valve device. In the present embodiment, the valve unit 21 includes only the pressure regulating valve 21A, but a configuration including other valves may also be employed.

<Valve unit>
Next, the detailed configuration of the valve unit 21 will be described with reference to FIG. FIG. 5 shows a cross section of the valve unit 21 taken along line AA in FIG. FIG. 5A shows a closed valve state, and FIG. 5B shows a valve opened state. The left side surface in FIG. 5 of the valve unit 21 is referred to as the left side surface, and the right side surface in FIG. 5 is referred to as the right side surface. As shown in FIG. 5, the frame 40 (base material) has a small volume cylindrical recess 40 a formed on the left side surface, and the right side surface has a larger diameter than the recess 40 a and the peripheral edge expands outward. And a concave portion 40b having a predetermined depth in the shape of a truncated cone. Both the concave portions 40a and 40b communicate with each other through a valve hole 52 formed in the central portion of the partition wall 51 that substantially divides both the concave portions 40a and 40b. Further, a groove 40c that communicates with the recess 40a is formed on the left side surface of the frame 40, and a groove 40d that communicates with the recess 40b is formed on the right side surface.

  On the left side surface of the frame 40, a film member 54 is thermally welded to substantially the entire surface including the outer side surface (bottom surface) of the lid 53 fitted in the recess 40a. An ink introduction path 55 is formed by being divided into a film member 54 and a groove 40c, and the ink introduction path 55 communicates with the connecting pipe portion 41 (see FIG. 3) on the upstream side (lower side in FIG. 5). On the downstream side (upper side in FIG. 5), the ink supply chamber 56 communicates as a fluid supply chamber defined by the lid 53 and the recess 40a. On the other hand, the pressure chamber 43 is partitioned by the film member 42 and the recess 40 b as described above, and communicates with the ink supply chamber 56 through the valve hole 52.

  As shown in FIG. 5, a valve body 57 is accommodated in the ink supply chamber 56 (valve chamber). The valve body 57 includes a disk-shaped plate-like portion 57a, a shaft portion 57b that protrudes vertically from the center of one surface of the plate-like portion 57a toward the pressure chamber 43, and the bottom surface of the plate-like portion 57a (the left surface in FIG. 5). And a convex portion 57c formed at the center. The shaft portion 57 b has an outer diameter slightly smaller than the diameter of the valve hole 52, and is inserted through the valve hole 52. A compression spring 59 (coil spring) as an urging means is interposed between the valve body 57 and the lid body 53. The urging force of the compression spring 59 causes the valve body 57 to be attached to the pressure chamber 43 side. It is energized. The compression spring 59 is held in a state where one end is extrapolated to the convex portion of the lid 53, and the other end is held in a state extrapolated to the convex portion 57 c of the valve body 57.

  Further, a sealing member 60 made of dome-shaped rubber or elastomer having a hole in the center is attached to the plate-like portion 57a. An annular valve seat 61 is formed on the surface of the partition wall 51 on the ink supply chamber 56 side so as to surround the valve hole 52. Further, an annular convex portion 60 a is formed on the outer peripheral surface of the seal member 60 at a position facing the valve seat 61.

  A bottomed cylindrical pressure receiving member 65 is fixed to the center of the inner surface of the diaphragm 42a by heat welding. The pressure receiving member 65 is positioned substantially coaxial with the valve body 57. In the pressure chamber 43, a negative pressure holding spring 66 as a fluid pressure setting spring is interposed between the pressure receiving member 65 and the partition wall 51, and the pressure receiving member 65 is moved to the atmosphere side (outside) by the negative pressure holding spring 66. It is pressed. In this embodiment, a coil spring is used as the negative pressure holding spring 66.

  The pressure receiving member 65 is fixed to the central portion of the inner surface of the diaphragm 42a in order to prevent the shaft portion 57b of the valve body 57 from directly contacting the diaphragm 42a. The pressure receiving member 65 is arranged such that its axis coincides with the axis of the diaphragm 42a.

  The pressure receiving member 65 has a cylindrical portion 65a that protrudes vertically toward the partition wall 51 side. The cylindrical portion 65a is formed to have an inner diameter slightly larger than the outer diameter (spring diameter) of the negative pressure holding spring 66, and one end portion of the negative pressure holding spring 66 is held in a state of being inserted into the cylindrical portion 65a. Yes. Further, a cylindrical portion 40e that substantially surrounds the valve hole 52 projects vertically on the surface of the partition wall 51 on the pressure chamber 43 side. The tubular portion 40e is formed with a notch 40f that penetrates in the radial direction. The negative pressure holding spring 66 abuts against the partition wall 51 with one end thereof being extrapolated to the tubular portion 40e, and the other end abuts against the inner bottom surface of the tubular portion 65a.

  In the power-on state of the recording apparatus 11, the pressurized ink is supplied from the ink cartridge 23 through the ink supply tube 35 into the ink supply chamber 56 by the pressure applied by driving the pressure pump 25, and the ink in the ink supply chamber 56 is It is in a state of being pressurized to a predetermined ink pressure (ink supply pressure Pis). The ink pressure Pink in the pressure chamber 43 positioned across the ink supply chamber 56 and the valve body 57 is held at a predetermined negative pressure (operating pressure) lower than the atmospheric pressure. In the valve-closed state shown in FIG. 5 (a), the diaphragm 42a has a valve more than the position C in FIG. In the body movement direction (left and right direction in FIG. 5), the body is slightly depressed toward the pressure chamber 43 side.

  Here, the force relationship when the pressure regulating valve 21A opens and closes will be described. The force acting on the valve body 57 includes a film reaction force Ffilm, a force Fi-a acting on the pressure receiving member 65 based on the differential pressure between the ink pressure and the atmospheric pressure, an urging force Fsp1 of the compression spring 59, and a negative pressure holding spring. 66 and a force Fs-i acting on the valve body 57 based on the differential pressure between the ink supply chamber 56 and the pressure chamber 43.

  Here, the film reaction force Ffilm is a force with which the deformed diaphragm 42a attempts to restore the original shape. The larger the deformation amount (deflection amount) of the diaphragm 42a, the larger the film reaction force Ffilm. The film reaction force Ffilm is transmitted to the shaft portion 57b (valve element 57) via the pressure receiving member 65.

  The force Fi-a acting on the pressure receiving member 65 based on the pressure difference between the ink pressure and the atmospheric pressure is applied to the pressure receiving member 65 based on the pressure difference between the ink pressure Pink in the pressure chamber 43 and the atmospheric pressure Pa outside the diaphragm 42a. It is the power to work. When ink is consumed by the recording head 20 and the ink in the pressure chamber 43 decreases, the differential pressure between the ink pressure Pink and the atmospheric pressure increases, and the force Fi-a increases. The force Fi-a acting on the pressure receiving member 65 acts on the valve body 57 as a force in the valve closing direction via the shaft portion 57b.

  Next, the biasing force Fsp1 of the compression spring 59 is a force by which the compression spring 59 biases the valve body 57 in the valve closing direction. The biasing force Fsp1 that the valve body 57 receives from the compression spring 59 is determined according to the compression amount of the compression spring 59. When the urging force Fsp1 at the compression amount when the valve body 57 is in the valve closing position is set to Fo, a displacement amount (compression amount) in the valve opening direction is determined based on the valve closing position, and the spring of the compression spring 59 When the constant is K1 and the displacement amount (compression amount) from the valve closing position is Δy, the urging force Fsp1 is expressed by Fsp1 = Fo + K1 · Δy.

  Further, the urging force Fsp2 of the negative pressure holding spring 66 is a force by which the negative pressure holding spring 66 presses the pressure receiving member 65 to the atmosphere side. The biasing force Fsp2 applies a force opposite to the force Fi-a acting on the pressure receiving member 65 to the pressure receiving member 65. Therefore, in order to displace the pressure receiving member 65 until the valve body 57 reaches the valve opening position, a negative pressure is applied. It is necessary to reduce the pressure chamber 43 to a lower ink pressure by an amount corresponding to the urging force Fsp2 of the holding spring 66. That is, the negative pressure holding spring 66 has a function of setting the ink pressure Pink of the pressure chamber 43 required for opening the valve low. Of course, the same effect can be obtained by eliminating the negative pressure holding spring 66 and increasing the biasing force of the compression spring 59 by the biasing force. However, even if the shaft portion 57b pushes the position deviated from the axis of the pressure receiving member 65 due to play of the valve hole 52 or the like, the negative pressure holding spring 66 arranged so as to surround the shaft portion 57b is not connected to the shaft portion 57b and the pressure receiving member 65. Since the pressure receiving member 65 is pushed around the contact point, the posture of the pressure receiving member 65 is difficult to tilt. In addition, the spring for setting the operating pressure is divided into the compression spring 59 and the negative pressure holding spring 66 and each is accommodated in separate chambers 43 and 56 so that the spring is accommodated only in the ink supply chamber 56. Compared to the above, the valve unit 21 is made thinner.

  The reason why the ink pressure Pink (working pressure) in the pressure chamber 43 is set to a negative pressure is to prevent the ink from leaking from the nozzles of the recording head 20 due to its own weight or capillary action. This is also because the ink pressure Pink needs to be maintained at a substantially constant operating pressure so that the mass (volume) of the ink droplets ejected from the nozzles by the driving of the ejection drive element is maintained substantially constant. The spring constants of the compression spring 59 and the negative pressure holding spring 66 are selected so that the pressure chamber 43 is set to a predetermined operating pressure (negative pressure).

  Finally, the force Fs-i acting on the valve element 57 based on the differential pressure between the ink supply chamber 56 and the pressure chamber 43 is the valve closing force Fclose acting on the valve element 57 upon receiving the ink supply pressure Pis, and the ink. This is a force represented by a difference from a force Fopen in the valve opening direction that acts on the valve body 57 upon receiving the pressure Pink. The force Fclose in the valve closing direction is represented by the product of the pressure receiving area S1 of the valve body 57 that receives the ink supply pressure Pis and the ink supply pressure Pis. The force Fopen in the valve opening direction is represented by the product of the pressure receiving area S2 of the valve body 57 that receives the ink pressure Pink and the ink pressure Pink. In the present embodiment, the pressure receiving area S1 where the valve body 57 receives the ink supply pressure Pis is equal to the area of the area surrounded by the outer periphery of the convex portion 60a of the seal member 60, and the pressure receiving area S2 receiving the ink pressure Pink is the seal. It is equal to the area of the region surrounded by the inner periphery of the convex portion 60a of the member 60. The force Fs-i acting on the valve element 57 based on the pressure difference between the ink pressures of the two chambers 43 and 56 is always the valve because the ink supply pressure Pis is negative while the ink supply pressure Pis is positive. It works in the valve closing direction of the body 57.

  Here, the working direction of the film reaction force Ffilm is determined by the bending direction of the diaphragm 42a. That is, when the diaphragm 42a bends in a direction that is convex toward the atmosphere side, the film reaction force Ffilm acts in the valve opening direction, while when the diaphragm 42a is bent in a direction that is recessed toward the pressure chamber 43, The film reaction force Ffilm works in the valve closing direction.

  In the present embodiment, the pressure regulating valve 21A is set to be used in a state where the diaphragm 42a is always recessed toward the pressure chamber 43 side. For this setting, the diaphragm 42a is held in a state of being recessed toward the pressure chamber 43 in a closed state in which the seal member 60 is in contact with the valve seat 61 and in a state in which the shaft portion 57b is in contact with the pressure receiving member 65. As described above, the axial length of the shaft portion 57b of the valve body 57 and the thickness of the pressure receiving member 65 are set. Even when the pressure regulating valve 21A changes from the open state to the closed state, that is, when the pressure receiving member 65 is located on the most atmospheric side in the usage range, the diaphragm 42a is recessed to the pressure chamber 43 side. Has been. For this reason, even if there is variation due to individual differences in the valve units 21, the film reaction force Ffilm always works in the valve closing direction in any operating range of any valve unit 21 (pressure adjusting valve 21A).

For this reason, the force acting on the valve body 57 is that the force in the valve closing direction is the urging force Fsp1 of the compression spring 59, the urging force Fsp2 of the negative pressure holding spring 66, the force Fs-i based on the ink pressure differential pressure, The force F film is a force Fi-a that acts on the pressure receiving member 65 based on the differential pressure. When the total force in the valve opening direction is greater than the total force in the valve closing direction, the valve element 57 moves in the valve opening direction. Here, since Fsp1 is expressed as a function having the displacement (compression amount) Δy1 as a variable, it can be expressed as Fsp1 (Δy1) (= Fo + k1 · Δy1). Further, Fsp2 is expressed as a function having the displacement amount Δy2 as a variable when the compression amount (displacement amount) from the natural length of the negative pressure holding spring 66 is Δy2 and the spring constant is K2, and therefore Fsp2 (Δy2) ( = K2 · Δy2). Further, Fs-i is expressed as a function Fs-i (Pink) having the ink pressure Pink as a variable when the ink supply pressure Pis is regarded as constant (constant). Further, Fi-a is expressed as a function Fi-a (Pink) with the ink pressure Pink as a variable when the atmospheric pressure Pa is regarded as constant (constant). F film is expressed as a function F film (ΔB) having a deflection amount ΔB from the position C as a variable. Therefore, the valve element 57 is displaced in the valve opening direction when the following conditional expression is satisfied.
Fsp1 (Δy1) + Fsp2 (Δy2) + Fs−i (Pink) + Ffilm (ΔB) <Fi−a (Pink) (1)
When the condition of the above expression (1) is satisfied and the valve element 57 moves in the valve opening direction, the springs 59 and 66 are compressed by the amount of movement of the valve element 57, respectively, so that Δy1 and Δy2 increase, and the diaphragm Since 42a is further recessed, ΔB increases. For this reason, Fsp1 (Δy1), Fsp2 (Δy2), and Ffilm (ΔB) all increase. Therefore, the valve body 57 stops at a position where the sum of the forces in the valve opening direction and the sum of the forces in the valve closing direction are balanced. Further, since the volume of the pressure chamber 43 decreases due to the displacement of the diaphragm 42a in the valve opening direction, the ink pressure Pink once decreased returns to the operating pressure. Since this proceeds in a very short time, the ink pressure Pink is actually maintained at the operating pressure. Thereafter, as the ink in the pressure chamber 43 decreases, the valve element 57 moves in the valve opening direction so as to maintain a balance between the total force in the valve opening direction and the total force in the valve closing direction. Then, when the convex portion 60a that has been pressed against the valve seat 61 is restored from the compressed state and the convex portion 60a is eventually separated from the valve seat 61, the pressure regulating valve 21A is opened.

  The timing of opening the valve is determined by the area of the compression spring 59, the negative pressure holding spring 66, the pressure receiving member 65, and the like. In the present embodiment, since the spring force of the springs 59 and 66 is weakened, the pressure receiving area which is the area of the portion where the pressure receiving member 65 is fixed to the diaphragm 42a is set to 1/3 of the diaphragm area, for example. It is as follows.

After the valve is opened, the valve body 57 moves in the valve closing direction when the following condition is satisfied.
Fsp1 (Δy1) + Fsp2 (Δy2) + Fs−i (Pink) + Ffilm (ΔB)> Fi−a (Pink) (2)
That is, when the sum of the forces in the valve closing direction exceeds the sum of the forces in the valve opening direction, the valve element 57 moves in the valve closing direction. When the pressure regulating valve 21A is opened, ink flows from the ink supply chamber 56 to the pressure chamber 43 through the valve hole 52 based on the differential pressure between the ink supply pressure Pis and the ink pressure Pink. When ink flows into the pressure chamber 43, the ink pressure Pink in the pressure chamber 43 increases. When the ink pressure Pink increases, the force Fi-a (Pink) acting on the pressure receiving member 65 based on the differential pressure decreases. Therefore, the condition of the above expression (2) is satisfied, and the valve body 57 moves in the valve closing direction.

  As the valve body 57 moves, the diaphragm 42a also moves in the valve closing direction, and the volume of the pressure chamber 43 increases, so that the ink pressure Pink that has once increased returns. Since this proceeds in a very short time, the ink pressure Pink is actually maintained at the operating pressure. Thereafter, as the ink flows into the pressure chamber 43, the valve element 57 moves in the valve closing direction so as to maintain a balance between the total force in the valve closing direction and the total force in the valve opening direction. As the valve element 57 moves in the valve closing direction, the gap between the convex portion 60a and the valve seat 61 is gradually narrowed, and the ink inflow speed is gradually decreased.

When the pressure regulating valve 21A is closed, the shaft portion 57b is in contact with the pressure receiving member 65. The opening / closing position of the valve element 57 is expressed by a displacement amount Δy1 when Δy1 = 0. Further, when the valve is opened (or closed), when the displacement amount Δy2 = Δy2o, the ink pressure Pink = Pinko, and the diaphragm displacement amount ΔB = ΔBo, the diaphragm 42a when the valve is opened is closed. The position of is indicated by a value of ΔBo that satisfies the following equation.
Fsp1 (0) + Fsp2 (Δy2o) + Fs−i (Pinko) + Ffilm (ΔBo) = Fi−a (Pinko)
By the way, in order to reduce the operating pressure of the valve unit 21 (pressure adjusting valve 21A) and to reduce the size, in the present embodiment, the compression spring 59 and the negative pressure holding spring 66 are small components having a weak spring force. . The reason why the operating pressure of the pressure regulating valve 21A is reduced is that the conventional high operating pressure may cause the ejection driving element in the recording head 20 to be driven and cause the mass of ink droplets ejected from the nozzles to fluctuate. Because there is. However, if the compression spring 59 and the negative pressure holding spring 66 are small components having a weak spring force in order to lower the operating pressure, the film reaction force Ffilm cannot be ignored, and this affects the operating pressure.

  Here, the state in which the diaphragm 42a is recessed toward the pressure chamber 43 is used as the use range of the pressure regulating valve 21A for the following reason. Consider a configuration in which the state in which the diaphragm 42a is convex toward the atmosphere side and the state in which the diaphragm 42a is recessed toward the pressure chamber 43 side coexist in the usage range of the pressure regulating valve 21A. In this case, the film reaction force Ffilm works in the valve opening direction when the diaphragm 42a is convex toward the atmosphere, and works in the valve closing direction when the diaphragm 42a is recessed toward the pressure chamber 43. That is, when the bending state of the diaphragm 42a is switched from convex to concave, the film reaction force Ffilm reduces the ink pressure Pink from the force in the direction in which the ink pressure Pink is increased (the valve opening direction) (the valve closing direction). ). For this reason, in the configuration in which the film reaction force Ffilm cannot be ignored, there is a variation in the load acting on the valve element 57 when the diaphragm shape is switched from convex to concave (corresponding to position C in FIG. 5A). appear.

  In the present embodiment, when the pressure regulating valve 21A is in the closed state, the pressure receiving member 65 welded to the film member 42 is in a state of being recessed toward the pressure chamber 43 side from the frame end surface. By doing so, it is possible to make the diaphragm 42a always be recessed toward the pressure chamber 43 immediately before reaching the opening / closing position Xo (see FIG. 4) when the valve body 57 opens and closes.

  When the film member 42 changes from a convex state on the outer side of the frame to a concave state on the inner side of the frame, the change in the film reaction force Ffilm acting on the shaft portion 57b becomes the largest. When the shape change of the film member 42 from the convex to the concave is at a position close to the opening timing of the valve body 57, a slight difference in the shape of the film member 42 causes the inside of the pressure chamber 43 when the valve body 57 is opened. Since the negative pressure becomes a variation factor, the above-described shape change is performed to shift this timing. In particular, when the spring load is reduced by the pressure adjusting valve 21A having a specification for setting the operating pressure low, the influence of the film reaction force Ffilm appears remarkably in the operating pressure, so that the above configuration is effective.

  Incidentally, the shaft portion 57b of the valve body 57 is set so as to abut on the surface of the pressure receiving member 65 at a right angle, but in reality, the angle at which the shaft portion 57b abuts on the surface of the pressure receiving member 65 varies between products. This is due to the dimensional tolerance of the parts, the assembly tolerance, the backlash due to the gap between the valve hole 52 and the shaft portion 57b, and the like, the inclination of the posture of the pressure receiving member 65, the inclination of the posture of the shaft portion 57b, This is because, for example, a deviation from the center (center of gravity) of the pressure receiving member 65 is brought about at the contact point. Due to variations in the angle at which the shaft portion 57b contacts the surface of the pressure receiving member 65, the force that the shaft reaction portion Fb receives the film reaction force Ffilm and the force that the shaft portion 57b receives the force Fi-a (Pink) of the pressure receiving member 65 It varies. In the configuration in which the change in the film reaction force Ffilm is the largest, the timing at which the valve is opened is the same as the valve opening timing. When the force Ffilm is transmitted to the shaft portion 57b, the force Ffilm is dispersed, which promotes the variation of the operating pressure due to individual differences of the valve units 21.

  On the other hand, the pressure regulating valve 21A of the present embodiment is used in a state where the diaphragm 42a is recessed toward the pressure chamber 43 in the usage range. For this reason, even if the film reaction force Ffilm cannot be ignored, the direction of the film reaction force Ffilm does not change in the range of use, and therefore the operating pressure is unlikely to vary due to individual differences.

  FIG. 4 is a graph showing how the diaphragm position changes during printing. In this graph, the horizontal axis is the diaphragm position X, and the vertical axis is the time T. Here, the diaphragm position X in the graph shows how the center position on the outer surface (right side surface in FIG. 5) of the diaphragm 42a changes in the valve body movement direction (left and right direction in FIG. 5). The position C is a diaphragm position that is flush with the outer surface of the portion where the film member 42 is joined to the frame 40, and is a position when the diaphragm 42a is in a flat state without bending.

  In the example of this graph, the pressure adjustment valve 21A is in a closed state before printing is started. When printing is started from this state (time To), ink droplets are ejected from the nozzles of the recording head 20, thereby reducing the ink in the pressure chamber 43. When the ink pressure Pink decreases as the ink decreases, the condition of the above equation (1) is satisfied, and the diaphragm position X () is maintained so as to maintain a balance between the total force in the valve opening direction and the total force in the valve closing direction. That is, the valve body 57) moves in the valve opening direction (left direction in the graph of FIG. 4).

  And when the diaphragm position X determined according to the position of the valve body 57 reaches the position Xo, the pressure regulating valve 21A is switched from the closed state to the opened state. While the opening is small and the amount of ink flowing into the pressure chamber 43 is less than the ink consumption, the condition of the above equation (1) is satisfied, the diaphragm position X is displaced in the valve opening direction, and the opening gradually increases. Become. When the ink inflow amount into the pressure chamber 43 exceeds the ink consumption amount, the volume of the pressure chamber 43 switches from decrease to increase, the condition of the above equation (2) is satisfied, and the direction in which the diaphragm position X is displaced is changed. It reverses in the valve closing direction (rightward in FIG. 4) at the position Xm (for example, the valve open state in FIG. 5B). When the diaphragm position X moves in the valve closing direction and reaches the position Xo, the pressure regulating valve 21A is closed. Thereafter, the diaphragm position X is displaced to, for example, a position Xc shown in FIG. 4 by compression of the convex portion 60a. The state in which the diaphragm position X is at the position Xc corresponds to the valve closing state shown in FIG.

  Thereafter, similarly, as the ink is consumed, the diaphragm position X repeatedly moves between the position Xc and the position Xm, and the ink pressure Pink in the pressure chamber 43 is equal to the ink pressure Pink (when the diaphragm position X is the position Xo). Operating pressure).

  When the pressure regulating valve 21A is changed from the open state to the closed state and the diaphragm position X is located on the outermost side (atmosphere side), the diaphragm 42a is positioned relative to the position C as shown in FIG. Thus, it is at a position Xc displaced by ΔBo toward the pressure chamber 43 side. Therefore, when the diaphragm position X is displaced to the outermost side (atmosphere side), the diaphragm 42a is recessed to the pressure chamber 43 side. For this reason, in the usage range (Xm ≦ X ≦ Xc) of the pressure regulating valve 21A, the direction of the film reaction force Ffilm does not change midway, so the ink pressure Pink in the pressure chamber 43 is in the direction of the film reaction force Ffilm. Does not fluctuate due to changes. As a result, the ink pressure in the ink chamber in the recording head 20 is stabilized, and the mass of the ink droplet ejected from the nozzle is stabilized by driving the ejection driving element.

As described above, according to the present embodiment, the following effects can be obtained.
(1) The valve unit 21 (pressure regulating valve 21A) is configured so that the diaphragm 42a is held in a recessed state toward the pressure chamber 43 even when the diaphragm 42a is changed from the open state to the closed state. Therefore, even if the position of the diaphragm 42a varies among products due to variations in the parts dimensions and parts assembly position of the valve unit 21, the diaphragm 42a at the outermost position in the usage range of the valve unit 21 It is held in a state of being recessed toward the chamber 43 side. As a result, it is possible to prevent fluctuations in the ink pressure Pink (operating pressure) due to the change in the direction of the film reaction force Ffilm in the use range regardless of individual differences of the valve units 21. For this reason, the mass of the ink droplet ejected from the nozzle of the recording head 20 can be stabilized.

  (2) When the pressure regulating valve 21A is opened as shown in FIG. 5B, the cylindrical portion 65a and the cylindrical portion 40e that hold both ends of the negative pressure holding spring 66 come close to each other. The gap becomes narrower. However, since the cylindrical portion 40e has the notch 40f, a flow path for the ink flowing through the valve hole 52 to flow into the pressure chamber 43 is secured. As a result, even if the gap between the cylindrical portions 65a and 40e that hold the negative pressure holding spring 66 becomes narrow when the valve is opened, ink can be smoothly supplied to the pressure chamber 43 without causing a large pressure loss when the valve is opened. .

  (3) Since the pressure receiving member 65 is fixed to the inner surface of the diaphragm 42a, the shaft portion 57b of the valve body 57 does not directly contact the diaphragm 42a. For this reason, the lifetime reduction of 21 A of pressure regulation valves resulting from damage etc. of the diaphragm 42a can be suppressed.

  (4) Since the negative pressure holding spring 66 disposed so as to surround the shaft portion 57b presses the pressure receiving member 65 around the contact portion of the shaft portion 57b, the pressure receiving member 65 is not easily tilted. Therefore, the variation in the angle at which the shaft portion 57b contacts the pressure receiving member 65 can be reduced. Further, since the urging spring for determining the ink pressure Pink is divided into the compression spring 59 and the negative pressure holding spring 66, the valving element 57 (shaft portion) is compared with the configuration in which the valving element 57 is urged by one spring. 57b) can be weakened, and the contact pressure of the shaft portion 57b based on the urging force of the compression spring 59 can be reduced.

In addition, embodiment is not limited above, You may change as follows.
(Modification 1) The surface (outer surface) opposite to the pressure chamber of the diaphragm faces is not limited to atmospheric pressure. It may be negative pressure. Furthermore, a positive pressure may be used. For example, the negative pressure chamber or the positive pressure chamber may be provided outside the diaphragm. For example, for example, a configuration shown in FIG. 13 in Patent Document 2, that is, a configuration in which a chamber disposed outside the diaphragm communicates with the outside (atmosphere) via a meandering groove can be employed.

  (Modification 2) The valve unit may have a single casing common to a plurality of ink colors, and a single casing may include a plurality of pressure regulating valves. Furthermore, the valve unit 21 may be configured to incorporate a valve (for example, a differential pressure valve) other than the pressure regulating valve 21A.

(Modification 3) A pressure regulating valve 21A as a valve device may be provided in the ink cartridge 23. In the case of an air pressurization type ink cartridge configuration, it is preferable that the outer surface of the diaphragm 42a be provided in a state open to the atmosphere. For example, an airtight chamber and an air release chamber in which the ink pack 23b is housed in the outer case 23a are provided, and the ink supply unit of the ink pack 23b is disposed in the air release chamber and connected to the ink supply unit in a communicating state. A pressure control valve is also placed in the open air chamber. Further, a configuration in which the pressure adjusting valve 21A is built in the ink outlet portion of the ink cartridge can be employed. Of course, the pressure regulating valve 21A as a valve device can be provided in an ink cartridge other than the ink pack type. For example, a configuration in which the pressure adjustment valve 21A is assembled in an outer case of an ink cartridge having an ink chamber in which ink is stored or an ink cartridge containing a porous body filled with ink can be employed.
(Modification 4) As the fluid pressure setting spring, a spring for urging the diaphragm in the valve opening direction may be provided instead of the negative pressure holding spring 66 for urging the diaphragm in the valve closing direction. For example, when a spring is provided in the pressure chamber 43, both ends of the spring are bonded to the partition wall side and the diaphragm side, respectively, so that the diaphragm is biased toward the pressure chamber side. A spring may be provided to urge the diaphragm from the outside (atmosphere side) in the valve opening direction. According to these configurations, the fluid pressure in the pressure chamber can be set to a value equal to or higher than the atmospheric pressure.

  (Modification 5) In the above-described embodiment, the recording apparatus 11 has a carriage. However, a fluid ejecting apparatus (for example, a line printer) having a full line head in which a plurality of fluid ejecting heads are fixed in a line without a carriage. The maintenance device of the present invention can also be employed.

  (Modification 6) In the above-described embodiment, the fluid ejecting apparatus is embodied as an ink jet recording apparatus. However, the present invention is not limited to this, and other fluids (liquid or functional material particles other than ink are dispersed or mixed in the liquid). And a fluid ejecting apparatus that ejects or discharges a liquid, a fluid such as a gel, and a solid that can be ejected by flowing as a fluid. For example, a liquid material ejecting apparatus that ejects a liquid material that is dispersed or dissolved in materials such as electrode materials and color materials (pixel materials) used in the manufacture of liquid crystal displays, EL (electroluminescence) displays, and surface-emitting displays. Further, a liquid ejecting apparatus that ejects a bio-organic matter used for biochip manufacturing, or a liquid ejecting apparatus that ejects a liquid that is used as a precision pipette and serves as a sample may be used. In addition, transparent resin liquids such as UV curable resin to form liquid injection devices that pinpoint lubricant oil onto precision machines such as watches and cameras, and micro hemispherical lenses (optical lenses) used in optical communication elements. A liquid ejecting apparatus that ejects a liquid onto the substrate, a liquid ejecting apparatus that ejects an etching solution such as acid or alkali to etch the substrate, and a fluid ejecting apparatus that ejects a fluid such as a gel (for example, a physical gel) It may be. And this invention is applicable to the maintenance apparatus of any one of these fluid ejecting apparatuses. In the present specification, the term “fluid” is a concept that does not include a fluid consisting only of gas. Examples of the fluid include liquid (inorganic solvent, organic solvent, solution, liquid resin, liquid metal (metal melt), etc. ), Liquids, fluids, and the like. Furthermore, the fluid may be a gas such as air or nitrogen.

Hereinafter, the technical idea grasped | ascertained from the said embodiment and each modification is described.
(1) The fluid is temporarily stored on the fluid supply path (35) for supplying the fluid from the fluid storing means (23) for storing the fluid to the fluid ejecting head (20) for ejecting the fluid. A pressure chamber in which the temporarily stored fluid decreases as the fluid is ejected from the head, and a negative pressure due to the decrease in the fluid in the pressure chamber (43) is detected to detect the pressure from the fluid supply path. In a valve device having an on-off valve (57, 59, 60, 66) for switching between supply and non-supply of fluid to a chamber, a diaphragm (42a) constituting a part of a wall surface of the pressure chamber, and a diaphragm provided on the diaphragm The pressure receiving member is displaced based on a differential pressure between the fluid pressure in the pressure chamber and the pressure on the opposite side of the pressure chamber across the diaphragm, and the pressure receiving member To displacement The on-off valve is configured to open and close, and the diaphragm is configured to be recessed toward the pressure chamber in a range from the open state to the closed state. apparatus.

  (2) The biasing means includes a first spring (59) that biases the valve body in the valve closing direction, and a second spring (66) that is provided in the pressure chamber and biases the pressure receiving member in the valve closing direction. The valve device according to claim 2, further comprising: The second spring corresponds to the fluid pressure setting spring in claims 3 and 4.

  (3) The gist of the present invention is a fluid storage container that is used by being detachably attached to the fluid ejecting apparatus, and includes the valve device according to the invention described above. According to this, by attaching the fluid container to the fluid ejection device, the valve device is attached to the fluid ejection device, and the same effect as the invention of the valve device can be obtained by the valve device.

FIG. 2 is a plan view illustrating a schematic configuration of a recording apparatus according to the present embodiment. FIG. 3 is a schematic diagram illustrating an ink supply system. The perspective view which shows a valve unit and a recording head. The graph which shows the relationship between the elapsed time at the time of printing, and a diaphragm position. (A) (b) AA line sectional view in Drawing 3 of a valve unit.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Recording apparatus as fluid ejecting apparatus, 15 ... Carriage, 20 ... Recording head as fluid ejecting means, 21 ... Valve unit, 21A ... Pressure regulating valve as valve apparatus, 23 ... As fluid supply source (fluid storage means) Ink cartridge, 25 ... Pressure pump, 35 ... Ink supply tube constituting flow path, 40 ... Frame, 40e ... Cylindrical part as second cylindrical part, 40f ... Notch, 42 ... Film member, 42a ... Diaphragm , 43 ... Pressure chamber, 51 ... Partition, 52 ... Valve hole, 53 ... Lid, 56 ... Ink supply chamber as fluid supply chamber, 57 ... Valve body constituting valve means, 57b ... Shaft, 59 ... Valve means And a compression spring as a biasing means, 60 ... a seal member constituting a valve means, 60a ... a convex part, 61 ... a valve seat, 65 ... a pressure receiving member, 65a ... a cylindrical part as a first cylindrical part, 6 ... negative pressure holding spring as the fluid pressure setting spring.

Claims (7)

A valve device for pressure adjustment provided in the middle of a flow path for supplying fluid from a fluid supply source to fluid ejecting means,
A fluid supply chamber communicating with the flow path on the upstream side;
A pressure chamber communicating with the flow path on the downstream side;
A diaphragm that constitutes a part of the wall surface of the pressure chamber and bends due to a pressure difference inside and outside the pressure chamber;
A pressure receiving member provided on the diaphragm;
Based on the fluid pressure in the pressure chamber when the fluid in the pressure chamber decreases, the valve-opening force that acts on the pressure receiving member increases, and the valve opens the fluid from the fluid supply chamber. Valve means for closing the valve based on the fact that the force in the valve opening direction acting on the pressure receiving member is weakened based on the fluid pressure of the pressure chamber when flowing into the chamber,
Configured to reduce the fluid pressure in the fluid supply chamber by opening and closing the valve means to maintain the pressure chamber at a predetermined operating pressure;
The valve means is configured to be held in a state where the diaphragm is recessed toward the pressure chamber even when the pressure chamber is in the operating pressure and is changed from the open state to the closed state. A valve device characterized by. The valve means includes a valve body partially accommodated in the fluid supply chamber, and an urging means for urging the valve body in a valve closing direction,
The valve body has a shaft portion inserted through a valve hole communicating with the fluid supply chamber and the pressure chamber, and the shaft portion is in direct or indirect contact with the pressure receiving member. The valve device according to claim 1. The pressure receiving member is fixed to an inner surface of the diaphragm on the pressure chamber side, and a shaft portion of the valve body is in contact with the pressure receiving member when the pressure chamber is at an operating pressure. 2. The valve device according to 2. 4. A fluid pressure setting spring provided in the pressure chamber and biasing the pressure receiving member in a valve closing direction or a valve opening direction of the valve means. Valve device. The fluid pressure setting spring is a coil spring, and the pressure receiving member has a first cylindrical portion that supports one end of the fluid pressure setting spring, and the pressure in a partition that partitions the fluid supply chamber and the pressure chamber. A second cylindrical portion that supports one end of the fluid pressure setting spring is formed on the chamber-side surface so as to surround the valve hole, and the second cylindrical portion has a notch penetrating in the radial direction. The valve device according to claim 4, wherein the valve device is formed. The valve according to any one of claims 1 to 5, wherein the valve is provided on a fluid supply source, a fluid ejection unit that ejects fluid, and a flow path for supplying the fluid of the fluid supply source to the fluid ejection unit. And a fluid supply device. A fluid ejecting apparatus comprising the fluid supply apparatus according to claim 6.

Images