JP2016132192A - Pressure regulating valve, liquid spray head and liquid spray device - Google Patents

Abstract

A pressure regulating valve, a liquid ejecting head, and a liquid ejecting apparatus capable of suppressing liquid leakage by suppressing accumulation of liquid components.
A communication flow path 514 provided through a partition wall 513 separating a primary chamber 511 and a secondary chamber 512 in a housing 51, and the communication flow path on the primary chamber 511 side of the partition wall 513. The valve body 55 that opens and closes the communication flow path by abutting and separating from the valve seat, and the opening of the secondary chamber 512 is sealed and the valve body 55 is large. A pressure-receiving film body 517 that opens and closes on the basis of atmospheric pressure, and a spacer 52 made of a conductive material is provided on the valve seat.
[Selection] Figure 4

Description

  The present invention relates to a pressure adjusting valve provided in the middle of a flow path to open and close the flow path, a liquid ejecting head including the pressure adjusting valve, and a liquid ejecting apparatus.

  As a liquid ejecting apparatus that ejects a liquid onto an ejected medium, for example, an ink jet recording apparatus that ejects ink as a liquid and performs printing on a paper, a recording sheet, or the like as an ejected medium is known.

  In such an ink jet recording apparatus, ink is supplied from a liquid storage means such as an ink tank to an ink jet recording head via a supply pipe such as a tube, and the ink supplied from the ink tank is used as a nozzle of the ink jet recording head. Some ejected as ink droplets from the opening. Further, there has been proposed an apparatus in which a pressure adjusting valve is provided in the middle of the flow path so that ink supplied from the liquid storage means is supplied to the ink jet recording head at a predetermined pressure (for example, Patent Document 1). And 2).

  The pressure regulating valve includes a valve seat and a valve body, and closes the flow path when the valve body comes into contact with the valve seat, and opens the flow path when the valve body is separated from the valve seat. It is like that. Such opening and closing of the valve seat and the valve body is performed by the pressure in the downstream flow path.

JP 2010-208048 A JP2013-132894A

  However, when the valve body and the valve seat of the pressure regulating valve repeatedly come into contact with each other, a component contained in the liquid accumulates, and the problem of blockage due to poor contact between the valve body and the valve seat due to the deposit occurs. is there.

  In particular, in the liquid ejecting head, when the pressure regulating valve is closed badly, the liquid leaks to cause liquid dripping from the nozzle opening, which contaminates the ejected medium or the liquid ejecting apparatus. is there.

  Such a problem is not limited to a pressure regulating valve used in a liquid jet head typified by an ink jet recording head, and similarly exists in pressure regulating valves used in other devices.

  In view of such circumstances, it is an object of the present invention to provide a pressure adjusting valve, a liquid ejecting head, and a liquid ejecting apparatus that can suppress liquid leakage by suppressing deposition of liquid components.

An aspect of the present invention that solves the above-described problems includes a communication channel provided through a partition that separates a primary chamber and a secondary chamber in a housing, and the communication channel on the primary chamber side of the partition. The valve opening is used as a valve seat, and the valve body that opens and closes the communication passage by contacting and separating from the valve seat and the opening of the secondary chamber are sealed and the valve body is opened and closed based on atmospheric pressure. A pressure receiving valve body that is operated, and the valve seat is provided with a spacer formed of a conductive material.
In such an embodiment, by providing a spacer formed of a conductive material on the valve seat, the potential of the spacer is stabilized, and the pigment contained in the liquid is aggregated by repeatedly contacting the valve body and the valve seat. , It is possible to suppress adhesion and deposition of aggregates.

  Here, it is preferable that the pressure receiving film body is provided with a pressure receiving plate made of a conductive material, and the spacer and the pressure receiving plate are electrically connected. According to this, it is possible to further stabilize the potential of the spacer and suppress deposits.

  Moreover, it is preferable that the said spacer and the said pressure receiving plate are formed with the same material. According to this, the spacer and the pressure receiving plate can be set to the same potential, and the potential can be further stabilized.

  The spacer is preferably grounded. According to this, the potential of the spacer can be further stabilized.

  The spacer is preferably charged with the same polarity as the surface of the pigment contained in the liquid supplied to the primary chamber and the secondary chamber. According to this, the spacer and the pigment can be electrically repelled, and the pigment can be prevented from adhering and depositing on the spacer.

  Moreover, it is preferable that the contact member which contacts at least the valve seat of the valve body is formed of a conductive material. According to this, it is possible to stabilize the potential of the contact member and to prevent the aggregated pigment from adhering to the contact member.

  The contact member is preferably grounded. According to this, the potential of the contact member can be further stabilized.

  The contact member is preferably charged with the same polarity as the surface of the pigment contained in the liquid supplied to the primary chamber and the secondary chamber. According to this, the contact member and the pigment can be electrically repelled, and the pigment can be prevented from adhering and depositing on the contact member.

According to another aspect of the invention, there is provided a liquid ejecting head including the pressure regulating valve according to the above aspect and a head body that ejects the liquid supplied from the pressure regulating valve.
According to this aspect, it is possible to suppress the liquid leakage by suppressing the deposition of the liquid component, and it is possible to realize a liquid ejecting head that suppresses the contamination by the liquid.

According to another aspect of the invention, there is provided a liquid ejecting apparatus including the pressure regulating valve according to the above aspect.
In such an aspect, it is possible to suppress the liquid leakage by suppressing the deposition of the liquid component, and it is possible to realize a liquid ejecting apparatus that suppresses the contamination by the liquid.

1 is a plan view of a recording apparatus according to Embodiment 1 of the invention. FIG. 3 is a cross-sectional view of the recording head according to the first embodiment of the invention. It is sectional drawing of the head main body which concerns on Embodiment 1 of this invention. It is principal part sectional drawing of the pressure control valve which concerns on Embodiment 1 of this invention. It is principal part sectional drawing of the pressure control valve which concerns on Embodiment 1 of this invention. It is principal part sectional drawing of the pressure control valve which concerns on Embodiment 2 of this invention. It is principal part sectional drawing of the pressure control valve which concerns on Embodiment 3 of this invention. It is principal part sectional drawing of the pressure control valve which concerns on Embodiment 4 of this invention.

Hereinafter, the present invention will be described in detail based on embodiments.
(Embodiment 1)
FIG. 1 is a plan view of an ink jet recording apparatus which is an example of a liquid ejecting apparatus according to Embodiment 1 of the invention.

  As shown in FIG. 1, the ink jet recording apparatus 1 includes a main body frame 2 having a rectangular shape in plan view. In the main body frame 2, a medium support member 3 that supports an ejected medium (not shown) extends along a first direction X that is a main scanning direction. A medium to be ejected such as paper is fed onto the medium support member 3 along a second direction Y orthogonal to the first direction X, which is the sub-scanning direction, by a paper feed mechanism (not shown). Yes. A rod-shaped guide shaft 4 extending in parallel with the first direction X of the medium support member 3 is installed above the medium support member 3 in the main body frame 2.

  A carriage 5 is supported on the guide shaft 4 so as to be capable of reciprocating in the first direction X along the guide shaft 4. The carriage 5 is connected to a carriage motor 7 provided on the main body frame 2 via an endless timing belt 6 that is hung between a pair of pulleys 6 a provided on the main body frame 2. Thus, the carriage 5 is reciprocated along the guide shaft 4 by driving the carriage motor 7.

  The carriage 5 holds an ink jet recording head 15 (hereinafter also simply referred to as a recording head 15), which is an example of the liquid ejecting head of the present embodiment. The recording head 15 of the present embodiment includes a head main body 20 and a pressure adjusting valve 50 that supplies ink from the ink tank 8 serving as a liquid storage unit to the head main body 20.

  As will be described in detail later, a plurality of nozzle openings are provided on the surface of the head main body 20 facing the medium support member 3, and by driving a pressure generating means (not shown) provided in the head main body 20. The ink droplets are ejected from the nozzle openings onto the ejection target medium fed onto the medium support member 3 so that the dots are landed by the ink droplets, that is, printing is performed.

  A tank holder 9 is provided on one end side in the first direction X of the main body frame 2, and a plurality of ink tanks 8 as liquid storage means are detachably mounted on the tank holder 9. In the present embodiment, two ink tanks 8 are provided. Each ink tank 8 contains different types (colors) of ink.

  Each ink tank 8 mounted on the tank holder 9 is connected to the pressure regulating valve 50 of the present embodiment via a supply pipe 10 such as a tube. The pressure adjusting valve 50 temporarily stores each color ink supplied from each ink tank 8 via each supply pipe 10, and individually supplies each color ink temporarily supplied to the head body 20. Is done.

  A maintenance unit 11 for performing maintenance such as cleaning of the head main body 20 is provided in a position near one end in the first direction X in the main body frame 2 and in the home position area of the carriage 5. The maintenance unit 11 includes a cap 12 for contacting the head body 20 so as to surround each nozzle opening of the head body 20 and receiving ink discharged from each nozzle opening by flushing. A suction pump (not shown) capable of suction.

  Then, with the cap 12 in contact with the head main body 20 so as to surround each nozzle opening of the head main body 20, the inside of the cap 12 is sucked by a suction pump (not shown), thereby increasing the viscosity of the ink from each nozzle opening. So-called cleaning is performed in which bubbles or the like are forcibly discharged into the cap 12.

  A recording head 15 mounted on such an ink jet recording apparatus 1 will be described with reference to FIGS. 2 is a cross-sectional view of an ink jet recording head that is an example of the liquid jet head according to the first embodiment of the present invention, and FIG. 3 is a cross-sectional view of a main part of the head main body.

  As shown in FIG. 2, the head main body 20 constituting the recording head 15 of the present embodiment includes a discharge unit 30 that ejects ink droplets and a flow path member 40 that supplies ink to the discharge unit 30.

  As shown in FIG. 3, the discharge unit 30 includes an actuator unit 31, a case 32 that can accommodate the actuator unit 31 therein, a flow path unit 33 joined to one surface of the case 32, and the other surface of the case 32. And a wiring board 34 fixed to the board.

  In the actuator unit 31 of the present embodiment, a piezoelectric actuator forming member 311 in which a plurality of piezoelectric actuators 310 are arranged in parallel along the direction in which the nozzle openings 334 are arranged, and the tip (one end) side of the piezoelectric actuator forming member 311 are free. The base plate (the other end) side has a fixed plate 312 joined as a fixed end so as to be an end.

  The piezoelectric actuator forming member 311 is formed by laminating the piezoelectric material 313 and the electrode forming materials 314 and 315 alternately.

  In the piezoelectric actuator forming member 311, a plurality of slits 316 are formed by, for example, a wire saw or the like, and the piezoelectric actuator 310 is arranged in parallel by cutting the tip end side into a comb-like shape. In the present embodiment, the direction in which the piezoelectric actuators 310 are juxtaposed is the direction in which the nozzle openings 334 are juxtaposed, and is arranged so as to be in the first direction X when mounted in the ink jet recording apparatus 1 described above. The Therefore, hereinafter, the direction in which the nozzle openings 334 are arranged side by side is referred to as a first direction X, and the direction orthogonal to the first direction X is referred to as a second direction Y as in the ink jet recording apparatus 1. Of course, when the head body 20 is mounted on the ink jet recording apparatus 1, the direction in which the nozzle openings 334 are arranged in parallel does not have to coincide with the first direction X, and is not particularly limited. In the present embodiment, a direction orthogonal to both the first direction X and the second direction Y is referred to as a third direction Z.

  Here, the region joined to the fixed plate 312 of the piezoelectric actuator 310 is an inactive region that does not contribute to vibration, and when a voltage is applied between the electrode forming materials 314 and 315 constituting the piezoelectric actuator 310, the fixed plate Only the region on the tip side that is not joined to 312 vibrates. And the front end surface of the piezoelectric actuator 310 is fixed to the diaphragm 331 mentioned later.

  Each piezoelectric actuator 310 of the actuator unit 31 is connected to a circuit board 318 such as a COF on which a drive circuit 317 such as a drive IC for driving the piezoelectric actuator 310 is mounted.

  The flow path unit 33 includes a flow path forming substrate 330, a vibration plate 331, and a nozzle plate 332.

  A plurality of pressure generation chambers 333 are arranged in parallel on the flow path forming substrate 330, and a nozzle plate 332 having a nozzle opening 334 corresponding to each pressure generation chamber 333 and a vibration plate 331 on both sides of the flow path forming substrate 330. And is sealed. In this embodiment, two rows in which the pressure generation chambers 333 are arranged in parallel are provided. The flow path forming substrate 330 is formed with a manifold 336 that communicates with each pressure generation chamber 333 via an ink supply path 335 and serves as a common ink chamber for the plurality of pressure generation chambers 333 for each column. . That is, in the present embodiment, a manifold 336 is formed for each row of pressure generation chambers 333.

  In addition, the tip of the piezoelectric actuator 310 is fixed to a region of the diaphragm of the flow path forming substrate 330 facing each pressure generation chamber 333.

  A compliance portion 337 is provided in a region corresponding to the manifold 336 of the vibration plate 331. The compliance portion 337 plays a role of absorbing the pressure change when the pressure change occurs in the manifold 336 and deforming the compliance portion 337 to keep the pressure in the manifold 336 constant.

  The case 32 is joined to the flow path unit 33 and provided with an ink introduction path 321 for supplying ink from the pressure regulating valve 50 connected to the ink tank 8 to the manifold 336. In the present embodiment, a total of two ink introduction paths 321 are provided, one for each manifold 336. The ink supplied from the ink tank 8 to the ink introduction path 321 via the pressure adjustment valve 50 is supplied to the manifold 336 and distributed to each pressure generation chamber 333 via the ink supply path 335.

  The case 32 is provided with accommodating portions 322 corresponding to the rows of pressure generating chambers 333. That is, in the present embodiment, two accommodating portions 322 are provided, and the actuator unit 31 is fixed in each accommodating portion 322.

  Further, a wiring board 34 is provided on the opposite side of the case 32 from the flow path unit 33, and the other end of the circuit board 318 having one end connected to the actuator unit 31 is connected to the wiring board 34. .

  In such a discharge unit 30, the volume of each pressure generation chamber 333 is changed by deformation of the piezoelectric actuator 310 and the vibration plate 331, and ink droplets are discharged from a predetermined nozzle opening 334.

  Further, as shown in FIG. 2, the flow path member 40 has a pressure regulating valve 50 fixed on one side and supplies ink from the pressure regulating valve 50 to the ejection unit 30 fixed on the other side. .

  Specifically, the flow path member 40 is provided with an ink communication path 41, and a filter 42 that removes foreign matters such as dust and bubbles contained in the ink is formed on one surface where the ink communication path 41 opens. A supply needle 43 provided on the filter 42 is provided.

  The supply needle 43 is inserted into a pressure adjusting valve 50 described later in detail. Ink from the pressure adjusting valve 50 passes through the inside of the supply needle 43 and is removed from the foreign matter by the filter 42, and then supplied to the ejection unit 30 via the ink communication path 41.

  The pressure adjustment valve 50 connected to the flow path member 40 and supplying ink from the ink tank to the recording head will be further described with reference to FIGS. 4 and 5 are enlarged cross-sectional views of the main part of the pressure regulating valve.

  In the present embodiment, as shown in FIG. 2, since two different types of ink are supplied to one head body 20, two pressure regulating valves 50 are fixed to the flow path member 40. .

  As shown in FIGS. 2, 4, and 5, each pressure regulating valve 50 is a valve that is provided in the middle of the flow path of ink and opens and closes the flow path. Specifically, the pressure regulating valve 50 of this embodiment includes a housing 51 and a valve body 55 provided in the housing 51.

  The housing 51 communicates with an ink tank 8 serving as a liquid storage unit via a supply pipe 10 and a primary chamber 511 to which ink is supplied from the ink tank 8 and an ink communication path 41 of the head body 20. A secondary chamber 512 is provided. The primary chamber 511 and the secondary chamber 512 are separated by a partition wall 513. The primary chamber 511 and the secondary chamber 512 communicate with each other via a communication channel 514 provided through the partition wall 513.

  The primary chamber 511 is formed by sealing a recess formed on one surface of the housing 51 with a lid member 515. In addition, one end of an inflow passage 516 is provided in the primary chamber 511 so as to communicate therewith. The ink tank 8 is connected to the other end of the inflow path 516 through the supply pipe 10.

  The secondary chamber 512 has a concave shape that opens on the side surface of the housing 51 opposite to the primary chamber 511. In addition, a film 517 that is a pressure-receiving film body is attached to a surface of the housing 51 where the secondary chamber 512 opens, and the opening of the secondary chamber 512 is sealed with the film 517. Further, one end of the outflow passage 518 communicates with the secondary chamber 512, and a seal member 519 is provided at the other end of the outflow passage 518 opposite to the one end communicating with the secondary chamber 512. Yes. The supply needle 43 of the flow path member 40 is inserted into the seal member 519 and connected to the outflow path 518.

  Here, the film 517 which is a pressure receiving film body can use a flexible material having resistance to the liquid (ink) supplied to the secondary chamber 512. In addition, as the film 517, it is preferable to use a material having a low moisture permeability, a gas permeability such as liquid oxygen or nitrogen. Examples of the material of the film 517 include a configuration in which a nylon film coated with vinylidene chloride (saran) is bonded and laminated to a high-density polyethylene film or a polypropylene (PP) film. Moreover, you may use a polyethylene terephthalate (PET) etc. as another material. The bonding method of the film 517 is not particularly limited, and heat welding, vibration welding, adhesion with an adhesive, or the like can be used.

  The part which comprises a part of wall surface of the secondary chamber 512 of such a film 517 becomes the diaphragm 517a. A pressure receiving plate 520 is provided on the surface of the diaphragm 517a on the secondary chamber 512 side. The pressure receiving plate 520 of the present embodiment has a disk shape having an outer shape smaller than that of the diaphragm 517a, and one end is extended from the diaphragm 517a and is fixed between the housing 51 and the film 517. Such a pressure receiving plate 520 is provided in order to prevent the valve body 55 that opens and closes the communication flow path 514 from directly contacting the film 517, and is made of a material having higher rigidity than the film 517, such as resin or Metal or the like can be used. In this embodiment, the pressure receiving plate 520 has an outer shape smaller than that of the diaphragm 517 a, but is not particularly limited thereto, and one end of the pressure receiving plate 520 is fixed between the film 517 and the housing 51 outside the secondary chamber 512. May be.

  The secondary chamber 512 penetrates in the bottom surface of the secondary chamber 512, that is, in the partition wall 513 facing the diaphragm 517 a of the housing 51 in the thickness direction that is the direction in which the primary chamber 511 and the secondary chamber 512 are partitioned. A communication channel 514 that communicates with the primary chamber 511 is provided. Ink from the primary chamber 511 flows into the secondary chamber 512 via the communication channel 514.

  Since the housing 51 has a complicated shape including the primary chamber 511, the secondary chamber 512, the communication channel 514, and the like, the resin material can be easily formed at low cost by molding. Of course, the material of the housing 51 is not limited to a resin material, and for example, a metal material, a ceramic material, or the like can be used. The housing 51 is formed of a material having higher rigidity than the film 517. Incidentally, if the rigidity of the housing 51 is low, for example, the shape of the secondary chamber 512 is not stable, the pressure difference between the ink pressure in the secondary chamber 512 and the atmospheric pressure outside the film 517 is not stable, and the valve body There is a possibility that the opening and closing operation of the communication channel 514 by 55 cannot be performed stably. Further, the shape of the communication channel 514 may not be stable, and the communication channel 514 may not be normally closed. Therefore, the housing 51 is preferably formed of a material having a certain degree of rigidity.

  A spacer 52 serving as a valve seat that contacts the valve body 55 is provided around the opening on the primary chamber 511 side of the communication channel 514 of the housing 51. Here, the spacer 52 is a material different from that of the housing 51 and is formed of a conductive material. Specifically, the housing 51 can be formed at a low cost by molding a resin material, for example. In contrast, the spacer 52 is formed of a conductive material such as a conductive resin or metal. In the present embodiment, the spacer 52 is made of a plate-like member provided with a communication port 521 that communicates with the communication channel 514.

  The method for fixing the spacer 52 to the housing 51 is not particularly limited. For example, the housing 51 may be molded (outsert molding) so as to be integrated with the spacer 52, and the spacer 52 may be formed on the housing 51. You may make it fix by welding by a heat | fever or vibration, adhesion | attachment by an adhesive agent, etc. The spacer 52 may be formed by forming a film on the housing 51 by sputtering or the like.

  The communication port 521 formed in such a spacer 52 has substantially the same inner diameter as the communication channel 514 of the housing 51. A valve body 55 is inserted through the communication channel 514 of the housing 51 and the communication port 521 of the spacer 52.

  The valve body 55 includes a valve body 550 having a shaft portion 551 inserted through the communication flow path 514 and the communication port 521, and a flange portion 552 provided at an end portion of the shaft portion 551 in the primary chamber 511, and a valve body And a contact member 560 fixed to the flange portion 552 of the main body 550.

  The shaft portion 551 of the valve body 550 has an outer diameter slightly smaller than the communication channel 514 and the communication port 521 of the spacer 52, and one end portion in the secondary chamber 512 is in contact with the central portion of the pressure receiving plate 520. Further, the other end of the shaft portion 551 opposite to the one end that contacts the pressure receiving plate 520 is disposed in the primary chamber 511, and the flange portion 552 is disposed at the other end in the primary chamber 511. Are integrally formed.

  The flange portion 552 is made of a circular plate member. Further, a contact member 560 made of an elastic material such as rubber or elastomer is fixed to the flange portion 552. The contact member 560 has an annular shape, and has a shape with a tip protruding toward the spacer 52. Specifically, the contact member 560 is continuously provided on the surface of the flange portion 552 on the side of the spacer 52 over the periphery of the shaft portion 551, and the thickness of the contact member 560 in the radial direction of the shaft portion 551. The taper has a shape that gradually decreases toward the spacer 52 side. In other words, the radial cross section of the contact member 560 has a substantially triangular shape, and the apex of the triangular shape is provided opposite to the spacer 52. In this embodiment, the contact member 560 is fixed to the spacer 52 side of the flange portion 552. However, the present invention is not limited to this. For example, the contact member 560 is formed in a shape that covers the flange portion 552. Then, the flange portion 552 may be fitted. Further, the valve body 550 and the contact member 560 may be integrated by, for example, integral molding. Thus, by integrating the valve body main body 550 and the contact member 560 by integral molding, it is possible to attach the contact member 560 in a state of being displaced or biased when the contact member 560 is attached to the valve body main body 550. While being able to suppress, the position shift by the contact member 560 contacting the spacer 52 repeatedly can be suppressed. Accordingly, the contact member 560 and the spacer 52 can be stably brought into contact with each other to improve the sealing performance.

  As shown in FIG. 5, such a contact member 560 is formed by abutting the protruding tip of the contact member 560 against the spacer 52 and elastically deforming the contact member 560, To close the communication channel 514 and the communication port 521.

  Here, the pigment particles contained in the ink ensure the dispersion stability in the solvent by electrically repelling the pigment particles by charging the surface. Such ink pigment accumulates in a minute space formed when the valve body and the valve seat come into contact with each other, and is condensed by compression and dehydration, and the aggregated ink adheres to and accumulates on the valve body and the valve seat. As a result, the valve is not reliably closed and ink leakage occurs. Since the contact member 560 of the valve body is formed of an elastic material, it is difficult to deposit and the deposit is easily peeled off due to elastic deformation of the valve seat.

  On the other hand, in this embodiment, by providing the spacer 52 on the valve seat with which the contact member 560 contacts, the charge is dispersed throughout the spacer 52 and the potential of the spacer 52 is stabilized. Therefore, it is possible to suppress the aggregated ink from adhering to and depositing on the spacer 52. That is, when the housing 51 made of a resin material is used as the valve seat without providing the spacer 52, the housing 51 is easily charged, and the aggregated ink adheres to and accumulates on the valve seat of the housing 51.

  The spacer 52 suppresses the accumulation of the aggregated ink in the region that contacts the contact member 560. Accordingly, it is only necessary that the spacer 52 has at least a surface that contacts the contact member 560 formed of a conductive material. That is, the spacer 52 is formed of a conductive material. The spacer 52 is formed entirely of a conductive material even when only a part of the surface that contacts the contact member 560 is formed of a conductive material. Including things. However, it is preferable to provide the spacer 52 having a relatively large area in order to disperse the charge throughout the spacer 52 and stabilize the potential.

  Thus, by providing the spacer 52 formed of a conductive material as the valve seat, deposits on the spacer 52 are suppressed, and the contact between the spacer 52 and the contact member 560 that is the valve seat is poor due to the deposit. It is possible to suppress the occurrence of blockage failure due to the ink and to prevent ink leakage.

  Further, a coil spring 56 is interposed between the flange portion 552 of the valve body 55 and the lid member 515 that defines the primary chamber 511, and the valve body 55 is pivoted by the biasing force of the coil spring 56. The axial direction of the portion 551 is biased toward the secondary chamber 512 with the moving axis direction as the moving axis direction.

  Here, the force acting on the valve body 55 includes the reaction force of the film 517, the force acting on the pressure receiving plate 520 and the diaphragm 517a upon receiving the ink pressure in the secondary chamber 512, the biasing force of the coil spring 56, and the supply of ink. There is a force acting on the valve body 55 under pressure.

  The reaction force of the film 517 is a force that the diaphragm 517a that has been bent and deformed tries to restore the original shape. The reaction force of the film 517 increases as the deformation amount of the diaphragm 517a, that is, the deflection amount increases. Such reaction force of the film 517 is transmitted to the shaft portion 551 through the pressure receiving plate 520.

  The force acting on the pressure receiving plate 520 and the diaphragm 517a upon receiving the ink pressure in the secondary chamber 512 is expressed by the product of the pressure receiving area of the pressure receiving plate 520 and the diaphragm 517a receiving the ink pressure and the ink pressure. When the liquid in the secondary chamber 512 is caused to flow downstream from the outflow passage 518 and the ink in the secondary chamber 512 decreases, the differential pressure between the ink pressure and the atmospheric pressure increases, and the pressure receiving plate 520 and the diaphragm 517a The power to work increases. The force acting on the pressure receiving plate 520 and the diaphragm 517a acts as a force in the valve opening direction on the valve body 55 via the shaft portion 551.

  The biasing force of the coil spring 56 is a force that biases the valve body 55 in the valve closing direction. As described above, in this embodiment, the valve body 55 applies a force to the pressure receiving plate 520 opposite to the force acting on the pressure receiving plate 520 and the diaphragm 517 a by the coil spring 56 due to the pressure of the ink in the secondary chamber 512. In order to displace the pressure receiving plate 520 until the valve body 55 reaches the valve opening position, it is necessary to reduce the ink in the secondary chamber 512 to a lower pressure by an amount corresponding to the urging force of the coil spring 56 ( Operating pressure).

  In such a pressure regulating valve 50, as shown in FIG. 4, the ink in the secondary chamber 512 is caused to flow downstream, and the pressure in the secondary chamber 512 is reduced to a negative pressure rather than the atmospheric pressure. The diaphragm 517a moves to the bottom surface side of the secondary chamber 512, and the pressure receiving plate 520 presses the valve element 55 against the urging force of the coil spring 56, so that the contact member 560 of the valve element 55 is interposed between the spacer 52 and the spacer 52. A gap is generated, and the communication channel 514 and the communication port 521 are opened, that is, opened. In addition, when ink is supplied from the primary chamber 511 to the secondary chamber 512 by this valve opening, and the decompression in the secondary chamber 512 is eliminated, the diaphragm 517a is moved to its original position by the biasing force of the coil spring 56. Then, the valve is closed (see FIG. 5).

(Embodiment 2)
FIG. 6 is an enlarged cross-sectional view of a main part of the pressure regulating valve according to the second embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the member similar to embodiment mentioned above, and the overlapping description is abbreviate | omitted.

  As shown in FIG. 6, the housing 51 of the pressure regulating valve 50 is provided with a spacer 52 at a portion where the contact member 560 of the valve body 55 contacts. In addition, the spacer 52 and the pressure receiving plate 520 are electrically connected via a wiring 53 provided in the housing 51. Incidentally, the pressure receiving plate 520 of the present embodiment is made of a conductive material. For example, the pressure receiving plate 520 and the spacer 52 are made of the same material, so that the spacer 52 and the pressure receiving plate 520 have the same potential. Can do.

  In this way, by electrically connecting the spacer 52 to the pressure receiving plate 520, electric charges are dispersed by the spacer 52 and the pressure receiving plate 520, and the potential of the spacer 52 can be further stabilized. In other words, by releasing the potential of the spacer 52 through the pressure receiving plate 520 that is a conductor having a large area, it is possible to prevent the spacer 52 from having a potential for adsorbing and depositing the pigment particles. Therefore, the accumulation of the aggregated ink on the spacer 52 can be further suppressed.

  In the present embodiment, the wiring 53 is provided inside the housing 51. However, the present invention is not particularly limited thereto. For example, the wiring 53 is provided on the inner wall surface of the housing 51, that is, the primary chamber 511 or the secondary chamber 512. It may be provided on the inner surface or the outer peripheral surface.

(Embodiment 3)
FIG. 7 is an enlarged cross-sectional view of a main part of a pressure regulating valve according to Embodiment 3 of the present invention. In addition, the same code | symbol is attached | subjected to the member similar to embodiment mentioned above, and the overlapping description is abbreviate | omitted.

  As shown in FIG. 7, the housing 51 of the pressure regulating valve 50 is provided with a spacer 52 at a portion where the contact member 560 of the valve body 55 contacts. In the present embodiment, the spacer 52 is grounded by the wiring 53 provided in the housing 51. Of course, the spacer 52 may be connected to the ground by the wiring 53. In the present embodiment, the wiring 53 is provided inside the housing 51, but is not particularly limited thereto. For example, the wiring 53 is provided on the inner wall of the primary chamber 511, and the lid member 515 and the housing 51 are provided. It may be derived to the outside from between.

  Thus, by connecting the spacer 52 to the ground or the ground, the electric charge of the spacer 52 can be dispersed and the potential of the spacer 52 can be further stabilized. Therefore, the accumulation of the aggregated ink on the spacer 52 can be further suppressed.

(Embodiment 4)
FIG. 8 is an enlarged cross-sectional view of a main part of a pressure regulating valve according to Embodiment 4 of the present invention. In addition, the same code | symbol is attached | subjected to the member similar to embodiment mentioned above, and the overlapping description is abbreviate | omitted.

  As shown in FIG. 8, a spacer 52 is provided in the housing 51 of the pressure regulating valve 50 at a portion where the contact member 560 of the valve body 55 contacts. In the present embodiment, the spacer 52 is connected to a wiring 53 provided in the housing 51. A constant voltage source 54 is connected to the wiring 53, and a voltage is supplied to the spacer 52 from the constant voltage source 54. Thus, the spacer 52 is charged by supplying the voltage from the constant voltage source 54. The spacer 52 is charged by the constant voltage source 54 so as to have the same polarity as the charging of the pigment particles contained in the ink. As a result, the ink aggregated on the charged spacer 52 is electrically repelled, and adhesion and deposition of the aggregated ink on the spacer 52 can be suppressed.

  In the present embodiment, the wiring 53 is provided inside the housing 51, but is not particularly limited thereto. For example, the wiring 53 is provided on the inner wall of the primary chamber 511, and the lid member 515 and the housing 51 are provided. It may be led to the outside from between the terminals and connected to the constant voltage source 54.

(Other embodiments)
As mentioned above, although each embodiment of this invention was described, the fundamental structure of this invention is not limited to what was mentioned above.

  For example, in each of the above-described embodiments, the spacer 52 is formed of a conductive material, but in addition to this, the contact member 560 of the valve body 55 may be formed of a conductive material. That is, if, for example, conductive rubber or the like imparted with conductivity by carbon fine powder is used as the contact member 560, the electric charge of the contact member 560 is dispersed to stabilize the potential of the contact member. Further, the agglomerated ink can be prevented from adhering and accumulating on the contact member 560. In the case where the contact member 560 is formed of a conductive material, the contact member 560 may be electrically connected to the pressure receiving plate 520 as in the above-described second to fourth embodiments. It may be connected to the ground. Alternatively, the contact member 560 may be connected to the constant voltage source 54 so that the contact member 560 is charged with the same polarity as the surface of the pigment contained in the ink. Regardless of the configuration, it is possible to further suppress the adhesion and accumulation of the ink aggregated on the surface of the contact member 560.

  Further, in each of the above-described embodiments, the piezoelectric actuator 310 that extends and contracts in the axial direction by alternately stacking the piezoelectric materials 313 and the electrode forming materials 314 and 315 as pressure generating means for causing a pressure change in the pressure generating chamber 333 is provided. As described above, the pressure generating means is not particularly limited. For example, the pressure generating means is formed by a method of forming a thin film type in which an electrode and a piezoelectric material are laminated by a lithography method and attaching a green sheet. A flexural vibration type piezoelectric actuator such as a thick film type can be used. Also, as a pressure generating means, a heating element is arranged in the pressure generating chamber, and droplets are discharged from the nozzle opening by bubbles generated by the heat generated by the heating element, or static electricity is generated between the diaphragm and the electrode. Thus, a so-called electrostatic actuator that discharges liquid droplets from the nozzle openings by deforming the diaphragm by electrostatic force can be used.

  In the ink jet recording apparatus 1 described above, the recording head 15 is mounted on the carriage 5 and moves in the first direction X. However, the present invention is not particularly limited thereto, and for example, the recording head 15 is fixed. Thus, the present invention can also be applied to a so-called line type recording apparatus that performs printing only by moving the ejection target medium in the second direction Y.

  In the above-described example, the ink jet recording apparatus 1 has a configuration in which the ink tank 8 which is a liquid storage unit is mounted on the tank holder 9 of the main body frame 2, but is not particularly limited thereto. A certain ink cartridge may be mounted on the carriage 5. The pressure adjustment valve 50 is not limited to the one mounted on the carriage 5, and the pressure adjustment valve 50 and the recording head 15 may be connected via a supply pipe such as a tube.

  Furthermore, the present invention is intended for a wide range of liquid ejecting apparatuses having a wide liquid ejecting head. For example, recording heads such as various ink jet recording heads used in image recording apparatuses such as printers, liquid crystal displays, and the like Liquid comprising a color material ejecting head used for manufacturing a color filter, an electrode material ejecting head used for forming an electrode such as an organic EL display and an FED (field emission display), a bioorganic matter ejecting head used for biochip manufacturing, etc. It can be used for an injection device.

  Further, the present invention is not limited to the pressure regulating valve used for the liquid ejecting head and the liquid ejecting apparatus, and can be used for a pressure regulating valve used for other devices.

  DESCRIPTION OF SYMBOLS 1 Inkjet recording apparatus (liquid ejecting apparatus), 2 Main body frame, 3 Medium support member, 4 Guide shaft, 5 Carriage, 6 Timing belt, 7 Carriage motor, 8 Ink tank (liquid storage means), 9 Tank holder, 10 Supply Tube, 11 maintenance unit, 12 cap, 15 ink jet recording head (liquid ejecting head), 20 head body, 30 discharge section, 31 actuator unit, 32 case, 33 flow path unit, 34 wiring board, 40 flow path member, 50 Pressure regulating valve, 51 housing, 52 spacer, 53 wiring, 54 constant voltage source, 55 valve body, 56 coil spring, 310 piezoelectric actuator (pressure generating means), 321 ink introduction path, 331 diaphragm, 332 Nozzle plate, 333 Pressure generating chamber, 334 Nozzle opening, 335 Ink supply path, 336 Manifold, 511 Primary chamber, 512 Secondary chamber, 513 Bulkhead, 514 Communication channel, 515 Lid member, 516 Inflow path, 517 Film ( Pressure receiving membrane body), 517a diaphragm, 518 outflow passage, 519 seal member, 520 pressure receiving plate, 550 valve body main body, 551 shaft portion, 552 flange portion, 560 contact member

Claims (10)

A communication passage provided through a partition wall that separates the primary chamber and the secondary chamber in the housing, and a surface of the partition wall on the primary chamber side where the communication passage opens, as a valve seat. A valve body that opens and closes the communication flow path in contact with and away from a seat; and a pressure receiving film body that seals the opening of the secondary chamber and opens and closes the valve body on the basis of atmospheric pressure,
The pressure regulating valve, wherein the valve seat is provided with a spacer made of a conductive material. The pressure receiving film body is provided with a pressure receiving plate made of a conductive material,
The pressure regulating valve according to claim 1, wherein the spacer and the pressure receiving plate are electrically connected.   The pressure regulating valve according to claim 2, wherein the spacer and the pressure receiving plate are formed of the same material.   The pressure regulating valve according to claim 1, wherein the spacer is grounded.   The said spacer is electrically charged by the same polarity as the surface of the pigment contained in the liquid supplied to the said primary chamber and the said secondary chamber, The Claim 1 characterized by the above-mentioned. Pressure regulating valve.   The pressure regulating valve according to any one of claims 1 to 5, wherein a contact member that contacts at least the valve seat of the valve body is formed of a conductive material.   The pressure regulating valve according to claim 6, wherein the contact member is grounded.   The pressure adjusting valve according to claim 6, wherein the contact member is charged with the same polarity as the surface of the pigment contained in the liquid supplied to the primary chamber and the secondary chamber.   A liquid ejecting head comprising: the pressure regulating valve according to claim 1; and a head main body that ejects liquid supplied from the pressure regulating valve.   A liquid ejecting apparatus comprising the pressure regulating valve according to claim 1.

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