CN118242471A - Pressure regulating valve - Google Patents

Abstract

The invention provides a pressure regulating valve capable of inhibiting jumping phenomenon. By providing the inner protruding portion (A1) on the valve seat portion (3), an intermediate pressure changing portion (B1) is formed, and the intermediate pressure changing portion (B1) becomes a buffer region in which the pressure changes gently. When fluid flows from the primary port (11A) side to the secondary port (12A) side through the intermediate pressure change portion (B1), first, the fluid flows from the primary port (11A) toward the intermediate pressure change portion (B1), and then, the fluid flows from the intermediate pressure change portion (B1) toward the secondary port (12A), whereby a pressure difference between the pressure in the intermediate pressure change portion (B1) and the secondary pressure acts on the valve element (4). By providing the intermediate pressure changing portion (B1), compared with a structure in which the pressure difference between the primary side pressure and the secondary side pressure directly acts on the valve element (4), the pressure difference can be suppressed from rapidly changing, and the pulsation phenomenon can be suppressed.

Description

Pressure regulating valve

Technical Field

The present invention relates to a pressure regulating valve.

Background

A pressure regulating valve having a pressure-sensitive bellows for biasing a valve portion of a valve needle has been proposed (for example, refer to patent document 1). In the pressure regulating valve described in patent document 1, the atmosphere is introduced into the internal space of the pressure-sensitive bellows, and the secondary pressure is introduced into the external space. The pressure difference between the inner space and the outer space changes the pressure of the pressure sensitive bellows, and the lift amount of the needle is determined by the pressure difference between the primary side pressure and the secondary side pressure, and the like.

Prior art literature

Patent literature

Patent document 1: japanese patent application laid-open No. 2022-134450

Disclosure of Invention

Problems to be solved by the invention

In the pressure regulating valve described in patent document 1, when the valve is opened under predetermined conditions, fluid flows from the primary side toward the secondary side. By such a flow of fluid, there is a case where the pressure difference between the primary side and the secondary side is reduced. In this case, the following operations may be repeated, that is, a jumping phenomenon may occur: for example, when the valve is opened, the fluid rapidly flows from the primary side toward the secondary side, the pressure difference is reduced in the vicinity of the valve element and the valve is closed, and when the pressure difference is increased by closing the valve, the valve is opened again, and when the fluid rapidly flows from the primary side toward the secondary side, the valve is closed again.

The invention aims to provide a pressure regulating valve capable of inhibiting a jumping phenomenon.

Means for solving the problems

The pressure regulating valve of the present invention is characterized by comprising: a valve housing having a first connection opening for connection of the first joint member and a second connection opening for connection of the second joint member; a valve seat portion provided in the valve housing and having a valve port communicating with the first joint member; a valve element that changes the opening degree of the valve port by moving toward the valve opening side or the valve closing side in the axial direction of the valve port; and a pressure-sensitive member which is housed in a housing portion of the valve housing and which communicates with the first joint member or the second joint member, wherein the valve housing is provided with a valve chamber communicating with the second joint member around the valve housing by applying a force in the axial direction corresponding to a pressure in the housing portion to the valve body, the valve body has a reduced diameter portion having an outer diameter which decreases toward the valve closing side, and a seat portion which is provided in the reduced diameter portion and is seated on the valve seat portion, and the valve seat portion has a contact portion which contacts the seat portion and has at least one of an inner protruding portion which protrudes toward the inner peripheral side than a first virtual surface extending from the contact portion in the axial direction, and a valve opening side protruding portion which protrudes toward the valve opening side than a second virtual surface extending from the contact portion in the radial direction.

According to the present invention described above, the intermediate pressure changing portion is formed between the inner protruding portion or the valve opening side protruding portion and the reduced diameter portion. That is, the intermediate pressure varying portion is a portion that makes a variation in the flow path cross-sectional area gentle on the primary side or the secondary side of the seating portion and the contact portion with respect to the valve seat portion, the configuration being formed by a surface extending from the contact portion along the first virtual surface and a surface extending along the second virtual surface. The intermediate pressure change portion serves as a buffer region in which the pressure changes gradually, and has a pressure intermediate between the primary side pressure and the secondary side pressure. When the fluid flows from the port side of the primary-side joint member to the port side of the secondary-side joint member via the intermediate pressure varying portion, first, the fluid flows from the primary side toward the intermediate pressure varying portion, and thereafter, the fluid flows from the intermediate pressure varying portion toward the secondary side, whereby a pressure difference between the pressure in the intermediate pressure varying portion and the primary-side pressure or the secondary-side pressure acts on the valve element. Therefore, by providing the intermediate pressure changing portion, compared with a structure in which the pressure difference between the primary side pressure and the secondary side pressure directly acts on the valve element, the pressure difference can be suppressed from rapidly changing, and the pulsation phenomenon can be suppressed.

In addition, the cross-sectional area of the flow path is minimized between the seating portion and the contact portion. If the flow path cross-sectional area is suddenly narrowed (the rate of change in the flow path cross-sectional area is large), the flow speed increases, and the fluid rapidly flows in, or the flow of the fluid tends to become unstable. By providing the intermediate pressure changing portion, the rate of change in the cross-sectional area of the flow path is reduced before and after the portion where the cross-sectional area of the flow path is smallest, and thus the sudden rise in flow velocity or the unstable flow velocity can be suppressed, and the pulsation phenomenon can be suppressed.

In this case, in the pressure regulating valve according to the present invention, the valve seat portion preferably has the inner protruding portion or the valve opening side protruding portion on the primary side with respect to the contact portion. According to this configuration, the region on which the pressure of the intermediate pressure varying portion acts is formed in the valve body on the primary side of the seating portion. The intermediate pressure change portion is lower than the primary pressure. Therefore, compared to a structure in which only the primary pressure acts on the valve body at a position on the primary side of the seating portion, the total pressure acting on the valve body can be reduced, and the force acting on the valve body can be reduced. Thus, even if the flow of fluid is unstable immediately after the valve is opened, the valve body can be prevented from being opened and closed with an excessive force, and the pulsation phenomenon can be prevented.

In the pressure regulating valve according to the present invention, it is preferable that the inner protruding portion includes an inclined surface whose inner diameter decreases from the contact portion toward the valve-closing side, or that the valve-opening side protruding portion includes an inclined surface whose inner diameter increases from the contact portion toward the valve-opening side. According to this configuration, since the inner protruding portion or the valve-opening side protruding portion includes the inclined surface, the change in the flow path cross-sectional area at the intermediate pressure changing portion becomes gentle, and the intermediate pressure between the primary side pressure and the secondary side pressure can be easily obtained.

In the pressure regulating valve according to the present invention, it is preferable that the valve seat portion has a stepped portion including a straight portion extending from the contact portion along the first virtual plane or the second virtual plane, and an extension portion extending continuously from the straight portion in the radial direction or the axial direction. According to such a configuration, for example, the inside protruding portion or the valve opening side protruding portion can be formed by forming a spot facing, and workability can be improved.

In the pressure regulating valve according to the present invention, it is preferable that the valve body is a needle valve body integrally having a rod-shaped portion and a needle-shaped distal end portion provided at one end of the rod-shaped portion and having the seat portion and the diameter-reduced portion. In the pressure regulating valve according to the present invention, it is preferable that the valve body has a spherical portion formed in a spherical shape and provided with the seating portion and the diameter-reduced portion. That is, the valve body may have a reduced diameter portion and a seating portion.

In the pressure regulating valve according to the present invention, it is preferable that the valve body is further provided with a seal member that guides the valve body in the axial direction, that partitions a space that is located on the valve opening side and communicates with the housing portion and a space that is located on the valve closing side and communicates with the second joint member side port, that the first joint member end port is a joint member of the primary side port and communicates with the housing portion, that the seal member applies pressure of the side port from the valve opening side and applies pressure of the first joint member end port from the valve closing side, and that the valve body applies pressure of the second joint member side port between the seal member and the contact portion, and that the seal member applies pressure of the first joint member end port at a position on the valve opening side and a position on the valve closing side than the contact portion.

According to this configuration, the valve body is guided by the seal member, so that the coaxiality of the seat portion and the contact portion can be ensured, and the operation can be stabilized. Further, the sealing member is configured to apply a primary side pressure from the valve opening side and a secondary side pressure from the valve closing side. The valve element and the valve seat portion are configured to apply a secondary side pressure from the valve opening side and a primary side pressure from the valve closing side. In this way, the force generated by the pressure from the valve opening side acting on the valve body, the sealing member, and the valve seat portion is made to be offset by the force generated by the pressure from the valve closing side, and the force acting on the valve body by the primary side pressure and the secondary side pressure can be reduced. Thus, the force acting on the valve body is mainly the force of the pressure sensitive member that changes according to the primary side pressure, and the valve can be opened according to the primary side pressure while suppressing the influence of the fluctuation of the secondary side pressure.

The effects of the invention are as follows.

According to the pressure regulating valve of the present invention, the pulsation phenomenon can be suppressed.

Drawings

Fig. 1 is a cross-sectional view showing a pressure regulating valve according to an embodiment of the present invention.

Fig. 2 is a cross-sectional view showing a main portion of the pressure regulating valve in a closed state.

Fig. 3 is a cross-sectional view showing a main portion of the pressure regulating valve in the valve-opened state.

Fig. 4 is a cross-sectional view showing a pressure regulating valve according to modification 1 of the present invention.

Fig. 5 is a cross-sectional view showing a main part of a pressure regulating valve according to modification 2 of the present invention.

Fig. 6 is a cross-sectional view showing a main part of the pressure regulating valve according to modification 3 of the present invention in a closed state.

Fig. 7 is a cross-sectional view showing a main part of the pressure regulating valve according to modification 3 of the present invention in an open state.

Fig. 8 is a cross-sectional view showing a main part of a pressure regulating valve according to modification 4 of the present invention.

Fig. 9 is a cross-sectional view showing a main part of a pressure regulating valve according to modification 5 of the present invention.

In the figure:

1. 1B-pressure regulating valve, 2, 20-valve housing, 2A-first connection opening, 2B-second connection opening, 22-second cylinder portion (housing portion), 24-sealing member, 25-housing portion, 215-intermediate chamber (valve chamber), 3, 30A, 30B-valve seat portion, 3A-valve port, 31-contact portion, 33, 304-inclined surface, 301-straight portion, 302-radially extending portion, 4, 40-valve body, 41-rod portion, 42-needle-shaped front end portion, 421, 44-diameter reducing portion, 423, 441-seating portion, 40A-ball portion, 51-pressure sensitive bellows (pressure sensitive member), 11-end joint tube (first joint member), 12-side joint tube (second joint member), A1, A2-inner protruding portion, A3-valve opening side protruding portion, C1-step portion, S1-first imaginary plane, S2-second imaginary plane.

Detailed Description

Embodiments of the present invention will be described with reference to the accompanying drawings. As shown in fig. 1, the pressure regulating valve 1 of the present embodiment includes a valve housing 2, a valve seat portion 3, a valve body 4, a pressure sensitive unit 5, and an adjustment spring unit 6.

The valve housing 2 includes a first tube 21, a second tube 22 connected to one end of the first tube 21, and a connector 23 connected to the other end of the first tube 21 and having a first connection opening 2A, and is formed in a cylindrical shape as a whole. The valve housing 2 may be formed of a metal such as brass, iron, aluminum, or stainless steel, and joined by brazing or welding. The valve housing 2 may have a cylindrical shape other than the cylindrical shape. Hereinafter, the axial direction (i.e., the extending direction) of the cylindrical valve housing 2 is referred to as the Z direction, and a plane orthogonal to the Z direction is referred to as the XY plane. In the Z direction, the side (upper side in fig. 1) on which the second tube portion 22 is provided with respect to the first tube portion 21 is set as the valve-open side, and the side (lower side in fig. 1) on which the connector 23 is provided with respect to the first tube portion 21 is set as the valve-closed side.

The first tube 21 has a second connection opening 2B formed at a side surface of the curved surface portion and open to one side in the X direction, and the second connection opening 2B is connected to the side joint pipe 12 as a second joint member. The first tube 21 is formed in a double tube shape, and the inner tube is a guide tube 211. The first cylindrical portion 21 has a shape with both ends open.

The second tube portion 22 extends from the first tube portion 21 toward the valve opening side, so that the pressure-sensitive bellows 51 accommodating the pressure-sensitive unit 5 becomes an accommodating portion, and the pressure-sensitive unit 5 operates according to the pressure of the internal space 22R thereof, as described later. The second cylindrical portion 22 has a shape with both ends open.

The connector 23 is formed in an annular shape and has an inner surface serving as a first connection opening 2A, and is inserted into an opening of the first cylinder 21 on the valve opening side. An end joint pipe 11 as a first joint member is connected to the first connection opening 2A.

In the present embodiment, as described above, the valve housing 2 has the first tubular portion 21, the second tubular portion 22, and the connector 23 in a separate manner, but the above-described components may be integrally formed.

The valve seat portion 3 is a valve seat member formed separately from the valve housing 2, and is formed in an annular shape as a whole and is housed in the first cylinder portion 21. The inner peripheral surface of the valve seat portion 3 serves as a valve port 3A and is provided on the valve closing side of the guide tube portion 211. Thereby, the valve port 3A communicates with the end joint pipe 11. The valve seat portion 3 may be formed of, for example, a suitable metal, resin, or the like, or may be formed integrally with the valve housing. The axial direction of the valve port 3A (the direction in which the fluid passes) coincides with the axial direction of the valve housing 2, that is, the Z direction.

The valve body 4 is a needle-shaped valve body integrally having a columnar rod-shaped portion 41 and a needle-shaped tip portion 42 continuous with the valve-closing side of the rod-shaped portion 41. As shown in fig. 2 and 3, the needle-like tip 42 has a reduced diameter portion 421 whose outer diameter decreases toward the tip end side (valve-closing side) and a tip end surface 422 extending along the XY plane. The reduced diameter portion 421 is formed to have a linear cross section as shown in fig. 1. A seating portion 423 that seats on the valve seat portion 3 is provided midway in the reduced diameter portion 421. That is, portions inclined with respect to the Z direction are formed on both sides via the seating portion 423. The outer diameter of the rod-shaped portion 41 is equal to the maximum outer diameter of the needle-shaped tip portion 42, and the outer diameter of the rod-shaped portion 41 is larger than the outer diameter of the seating portion 423.

The rod-shaped portion 41 is inserted into the guide cylinder portion 211 and guided to move in the Z direction. A seal member 24 made of an elastic member such as rubber or resin is provided at the valve-opening side end of the guide tube 211. The outer diameter of the rod-shaped portion 41 may be slightly smaller than the inner diameter of the guide tube portion 211 or slightly larger than the inner diameter of the seal member 24 in a natural state (a state before attachment). Thereby, the rod-shaped portion 41 is in sliding contact with the sealing member 24, and the rod-shaped portion 41 is mainly guided by the sealing member 24.

An annular spring seat 43 is provided on the valve body 4. The valve opening spring 9 that applies a force to the valve body 4 toward the valve opening side is provided in the first cylinder portion 21, and the spring seat portion 43 is disposed on the valve opening side with respect to the valve opening spring 9 to receive the force. The first tube 21 is formed with a spring seat 212 which is a surface facing the valve opening side and is located outside the guide tube 211, and the valve opening spring 9 is arranged between the spring seat 212 and the spring seat 43.

The pressure-sensitive unit 5 includes a pressure-sensitive bellows 51 as a pressure-sensitive member, a bellows upper cover 52, and a connecting rod 53 extending in the Z direction, and is housed in the second tube portion 22. The bellows upper cover 52 has a through hole 521 through which the valve-opening-side end 531 of the connecting rod 53 is inserted, and is provided to close the valve-opening-side opening of the second tube portion 22. At this time, the outer peripheral surface of the bellows upper cover 52 is hermetically connected to the inner peripheral surface of the second tube portion 22. The connecting rod 53 has a large diameter portion 532 on the valve-closing side of the valve-opening side end portion 531, the outer diameter of the large diameter portion 532 being larger than the inner diameter of the through hole 521, and the outer diameter of the valve-opening side end portion 531 being smaller than the inner diameter of the through hole 521.

The pressure-sensitive bellows 51 is formed in a cylindrical shape extending in the Z direction, and an end on the valve opening side thereof is connected to the bellows upper cover 52, and an end on the valve closing side thereof is connected to an end on the valve closing side of the connecting rod 53. The elastic force of the pressure-sensitive bellows 51 itself biases the valve element 4 toward the valve closing side.

Since the pressure-sensitive bellows 51 is housed in the second tube portion 22 as the housing portion, the pressure in the second tube portion 22 acts as the outside pressure. In contrast, the atmosphere is always introduced into the internal space of the pressure-sensitive bellows 51 through the gap between the valve-opening side end 531 and the through hole 521 and the gap between the bellows upper cover 52 and the valve-opening side connecting member 7 described below. That is, the atmospheric pressure acts on the pressure-sensitive bellows 51 as the inside pressure. The pressure-sensitive bellows 51 deforms according to a pressure difference between the outside pressure and the inside pressure, and is configured such that the higher the outside pressure is, the lower the biasing force toward the valve-closing side is.

The adjustment spring unit 6 includes an adjustment spring 61, a spring housing 62, a spring seat member 63, and an adjustment screw member 64. The adjustment spring 61 may be, for example, a multi-coil wave spring or a coil spring having the Z direction as the axis direction, and applies a biasing force by compressing in the Z direction. The spring case 62 is connected to the valve-opening-side end of the second tube 22 by, for example, screw coupling, and houses the adjustment spring 61. The spring seat member 63 is provided on the valve closing side with respect to the adjustment spring 61, and the adjustment screw member 64 is provided on the valve opening side with respect to the adjustment spring 61. That is, the adjustment spring 61 is provided between the spring seat member 63 and the adjustment screw member 64 in the Z direction.

The outer peripheral surface of the adjustment screw member 64 is formed with a male screw portion 641, and the inner peripheral surface of the spring housing 62 is formed with a female screw portion 621, and the male screw portion 641 is screwed with the female screw portion 621. The adjustment screw member 64 has a recess for rotation operation on the valve opening side surface, and is moved in the Z direction by the screw feed mechanism by rotation, whereby the distance from the spring seat member 63 changes. Thereby, the compression amount of the adjustment spring 61 is changed, and the urging force can be adjusted. The inner space of the spring housing 62 communicates with the outer space and is introduced into the atmosphere.

A valve-opening-side connecting member 7 is provided between the pressure-sensitive unit 5 and the adjustment spring unit 6, and a valve-closing-side connecting member 8 is provided between the pressure-sensitive unit 5 and the valve body 4, thereby transmitting the force in the Z direction. The valve-opening-side connecting member 7 and the valve-closing-side connecting member 8 are spherical, and the valve-opening side and the valve-closing side of the pressure-sensitive unit 5, the valve-closing side of the adjustment spring unit 6, and the valve-opening side of the valve element 4 are each formed concave so that balls can be arranged. Between the pressure-sensitive unit 5 and the valve-opening side connection member 7, the atmosphere can pass between the bellows upper cover 52 and the valve-opening side connection member 7.

Here, the flow of the fluid in the pressure regulating valve 1 and the pressures of the respective portions will be described. First, in the pressure regulating valve 1, the end joint pipe 11 connected to the first connection opening 2A is a primary-side joint member, and the side joint pipe 12 connected to the second connection opening 2B is a secondary-side joint member. That is, the end joint pipe 11 has a primary side port 11A on the inner side thereof, and the side joint pipe 12 has a secondary side port 12A on the inner side thereof.

The first tube 21 has a pressure equalizing hole 213 extending in the Z direction so as to pass through a position at which the valve opening spring 9 is disposed outside the guide tube 211. The pressure equalizing hole 213 connects the valve-closing-side end and the valve-opening-side end of the first tube 21, that is, connects the primary-side port 11A of the end joint pipe 11 formed in the connector 23 to the internal space 22R of the second tube 22.

The first tube 21 has a communication path 214 formed therein for communicating the secondary port 12A of the side joint tube 12 with the inside of the guide tube 211. Thereby, the pressure in the intermediate chamber 215 formed between the guide cylinder portion 211 and the valve seat portion 3 is equal to the pressure of the secondary port 12A. The intermediate chamber 215 communicates with the secondary port 12A of the side joint pipe 12, and is formed around the valve body 4, and functions as a valve chamber.

The seal member 24 is provided to divide a space on both sides in the Z direction. The space on the valve opening side of the seal member 24 is a space that communicates with the internal space 22R of the second cylinder 22 that is the housing portion, and the pressure (primary side pressure) of the primary port 11A acts. The space on the valve-closing side of the seal member 24 is a space that communicates with the intermediate chamber 215 (i.e., a space that communicates with the secondary-side port 12A), and the pressure of the secondary-side port 12A (secondary-side pressure) acts. In this way, the seal member 24 hermetically divides the space of the primary side pressure and the space of the secondary side pressure.

The valve element 4 is configured to apply a primary side pressure to a position on the valve opening side of the seal member 24, apply a secondary side pressure between the seal member 24 and the valve seat portion 3, and apply a primary side pressure to a position on the valve closing side of the valve seat portion 3. Further, the pressure acting on the needle-like front end portion 42 of the valve element 4 will be described in more detail below.

The valve body 4, the sealing member 24, and the valve seat portion 3 are arranged as described above, and the primary side pressure and the secondary side pressure are applied to the respective components. That is, the sealing member 24 is operated with the primary side pressure from the valve opening side and the secondary side pressure from the valve closing side. The valve element 4 and the valve seat portion 3 are subjected to a secondary side pressure from the valve opening side and a primary side pressure from the valve closing side. In this way, the force generated by the pressure from the valve opening side acting on the valve body 4, the sealing member 24, and the valve seat portion 3 is offset by the force generated by the pressure from the valve closing side. The term "offset" here includes not only the case where the forces are completely offset from each other and the resultant force is 0, but also the case where the resultant force remains slightly although the forces are offset from each other.

As described above, the force of the pressure-sensitive unit 5 and the adjustment spring unit 6 toward the valve-closing side and the force of the valve-opening spring 9 toward the valve-opening side mainly act on the valve body 4. The force generated by the pressure difference between the primary side pressure and the secondary side pressure also slightly acts, but the force generated by the pressure from the valve opening side and the force generated by the pressure from the valve closing side are offset, so that the force is sufficiently small here. When the primary pressure increases, the outside pressure of the pressure sensitive unit 5 increases and the biasing force toward the valve-closing side decreases. When the resultant force of the pressure sensitive unit 5 and the adjustment spring unit 6 toward the valve closing side is lower than the force of the valve opening spring 9 toward the valve opening side, the valve element 4 starts the valve opening operation. By adjusting the biasing force of the adjustment spring unit 6, the primary side pressure at the time of starting valve opening can be adjusted.

Next, a detailed structure of the valve seat portion 3 will be described with reference to fig. 2 and 3. First, the valve seat portion 3 has a contact portion 31 as a corner portion that contacts the seating portion 423 of the valve body 4. The valve seat portion 3 has an upper surface 32 extending from the contact portion 31 toward the outer peripheral side along the XY plane and toward the valve opening side, an inclined surface 33 having an inner diameter that decreases from the contact portion 31 toward the valve closing side, and an inner surface 34 extending from the valve closing side end of the inclined surface 33 in the Z direction. That is, a corner (contact portion 31) is formed between the upper surface 32 and the inclined surface 33, and a corner 35 is also formed between the inclined surface 33 and the inner surface 34. In the valve seat portion 3, the inner diameters of the inner surface 34 and the corner portion 35 are valve port diameters, and the inner diameters of the upper surface 32 and the contact portion 31 are seal diameters, which are larger than the inner diameters. The outer diameter of the rod-shaped portion 41 (i.e., the inner diameter of the deformed seal member 24) is slightly larger than the seal diameter. Since the outer diameter of the rod-shaped portion 41 (i.e., the inner diameter of the deformed seal member 24) is slightly larger than the seal diameter, the force generated by the pressure from the valve opening side is offset with the force generated by the pressure from the valve closing side as described above.

The inclined surface 33 extends toward the inner peripheral side with respect to a first virtual surface S1 extending in the Z direction from the contact portion 31. That is, the portion of the valve seat portion 3 constituted by the inclined surface 33 and the inner surface 34 is an inner protruding portion A1 protruding inward from the first virtual surface S1. The upper surface 32 extends so as to overlap with a second imaginary plane S2 extending in the radial direction from the contact portion 31.

In the present embodiment, since the end joint pipe 11 is a primary-side joint member, in the valve-opened state shown in fig. 3, after the fluid passes through the inner side of the inner surface 34 toward the upper side, the fluid changes its path toward the outer peripheral side in the vicinity of the seating portion 423 and the contact portion 31, and then flows toward the outer peripheral side. At this time, the cross-sectional area of the fluid passage is constant inside the inner surface 34 until reaching the needle-like tip end 42, gradually decreases between the reduced diameter portion 421 and the inner surface 34 according to the inclination angle of the reduced diameter portion 421, gradually decreases between the reduced diameter portion 421 and the inclined surface 33 according to the inclination angles of the reduced diameter portion 421 and the inclined surface 33, becomes minimum between the contact portion 31 and the seating portion 423, and then gradually increases according to the inclination angle of the reduced diameter portion 421.

The angle between the reduced diameter portion 421 and the inclined surface 33 is smaller than the angle between the reduced diameter portion 421 and the inner surface 34. That is, the amount of change in the cross-sectional area of the flow path between the reduced diameter portion 421 and the inclined surface 33 is smaller, that is, the change is gentle, when the flow path advances a predetermined distance in the Z direction, than between the reduced diameter portion 421 and the inner surface 34. Thus, a throttle portion in which the pressure is gently changed (the flow path is gently narrowed) is formed at the primary side between the contact portion 31 having the smallest cross-sectional area of the flow path and the seating portion 423. The pressure at the throttle portion in this way becomes a value intermediate between the primary side pressure and the secondary side pressure in the valve-open state. An intermediate pressure changing portion B1 as such a throttle portion is formed between the reduced diameter portion 421 and the inclined surface 33. Further, the region of the needle tip portion 42 where the intermediate pressure changing portion B1 is formed can be changed according to the valve opening degree.

The pressure applied to the needle tip portion 42 in the valve-opened state is as follows. That is, the primary pressure is applied to the region of the front end surface 422 and the reduced diameter portion 421 located inside the inner surface 34, the pressure of the intermediate pressure changing portion B1 is applied to the region of the reduced diameter portion 421 facing the inclined surface 33, and the secondary pressure is applied to the region of the reduced diameter portion 421 on the outer peripheral side of the position facing the contact portion 31. In contrast, in the configuration in which the inner protruding portion A1 and the intermediate pressure varying portion B1 are not formed, the primary side pressure is applied to the reduced diameter portion at a position on the inner peripheral side than the position facing the contact portion, and the secondary side pressure is applied to the outer peripheral side thereof. The intermediate pressure change portion B1 is lower than the primary pressure. Therefore, by forming the inner protruding portion A1 and the intermediate pressure varying portion B1, the pressure acting on the reduced diameter portion 421 from the valve closing side is reduced, and the force acting on the valve element 4 toward the valve opening side is reduced.

According to the present embodiment described above, the intermediate pressure changing portion B1 is formed by providing the inner protruding portion A1, and the intermediate pressure changing portion B1 becomes a buffer region in which the pressure changes gently. When the fluid flows from the primary port 11A side to the secondary port 12A side via the intermediate pressure varying portion B1, first, the fluid flows from the primary port 11A toward the intermediate pressure varying portion B1, and then, the fluid flows from the intermediate pressure varying portion B1 toward the secondary port 12A, so that a pressure difference between the pressure in the intermediate pressure varying portion B1 and the secondary pressure acts on the valve element 4. Therefore, by providing the intermediate pressure changing portion B1, compared with a configuration in which the pressure difference between the primary side pressure and the secondary side pressure is directly applied to the valve element 4, the pressure difference can be suppressed from rapidly changing, and the pulsation phenomenon can be suppressed.

Further, by providing the intermediate pressure changing portion B1, the rate of change in the cross-sectional area of the flow path is reduced before and after the portion (the contact portion 31 and the seating portion 423) where the cross-sectional area of the flow path is smallest, and the sudden rise in the flow velocity or the unstable flow velocity is suppressed, so that the pulsation phenomenon can be suppressed.

Further, by providing the inner protruding portion A1 on the primary side (i.e., the end joint pipe 11 and the first connection opening 2A side) with respect to the contact portion 31, a region on which the pressure of the intermediate pressure changing portion B1 acts is formed in the valve body 4 on the primary side of the seating portion 423. The intermediate pressure change portion B1 is lower than the primary pressure. Therefore, compared to a structure in which only the primary pressure acts on the valve body at a position on the primary side of the seating portion, the pressure acting on the valve body 4 can be reduced, and the force acting on the valve body 4 can be reduced. Thus, even if the flow of fluid is unstable immediately after the valve is opened, the valve body 4 can be prevented from being opened and closed with an excessive force, and the pulsation phenomenon can be prevented.

Further, since the inner protruding portion A1 includes the inclined surface 33, the change in the flow path cross-sectional area at the intermediate pressure changing portion B1 becomes gentle, and the pressure intermediate between the primary side pressure and the secondary side pressure is easily obtained.

Further, by providing the seal member 24 for guiding the valve body 4 in the Z direction, the coaxiality between the seat portion 423 and the contact portion 31 can be ensured, and the operation can be stabilized. The force generated by the pressure from the valve opening side acting on the valve element 4, the sealing member 24, and the valve seat portion 3 is offset with the force generated by the pressure from the valve closing side, and the force acting on the valve element 4 by the primary side pressure and the secondary side pressure is reduced, so that the force acting on the valve element 4 mainly becomes the acting force of the pressure sensitive bellows 51 that changes according to the primary side pressure, and the valve can be opened according to the primary side pressure while suppressing the influence of the fluctuation of the secondary side pressure.

The present invention is not limited to the above-described embodiments, and other configurations, etc. that can achieve the objects of the present invention are included, and modifications, etc. shown below are also included in the present invention. For example, in the above embodiment, the pressure adjustment valve 1 is configured such that the end joint pipe 11 connected to the first connection opening 2A on the end side is used as the joint member on the primary side, and the side joint pipe 12 connected to the second connection opening 2B on the side is used as the joint member on the secondary side, but the pressure adjustment valve may be configured such that the joint member on the secondary side is connected to the end side and the joint member on the primary side is connected to the side. As an example of the pressure adjustment valve used in this way, fig. 4 shows a pressure adjustment valve 1B of modification 1.

The pressure regulating valve 1B includes a valve housing 20, a valve seat portion 30, a valve body 40, a pressure sensitive unit 5, and an adjustment spring unit 6, and differs from the above-described embodiment in the main valve housing 20, the valve seat portion 30, and the valve body 40, and the differences are described below.

The valve housing 20 is formed of one member having the first connection opening 2A and the second connection opening 2B formed therein. The valve housing 20 has a housing portion 25 housing the pressure-sensitive bellows 51 of the pressure-sensitive unit 5, and the housing portion 25 communicates with a port 12B of the side joint pipe 12, which is a primary side joint member connected to the second connection opening 2B, and is introduced into the primary side pressure.

The valve seat portion 30 has a guide tube 300 for guiding the rod-like portion of the valve body 40, and no sealing member is provided in the guide tube 300. The size, shape, etc. of each portion of the valve body 40 are slightly different from those of the valve body 4 of the above embodiment, but have the same reduced diameter portion 421 as the valve body 4. A spring seat member 300A is attached to the outside of the guide tube 300, and the spring seat member 300A is positioned on the valve closing side with respect to the valve opening spring 9 to receive a force.

In modification 1, the valve seat portion 30 also has the inner protruding portion A1 and the intermediate pressure changing portion B1 similar to those in the above embodiment. In the above embodiment, the valve-closing side is the primary side with respect to the contact portion 31 and the seating portion 423, whereas in modification 1, the valve-closing side is the secondary side with respect to the contact portion 31 and the seating portion 423. That is, the intermediate pressure changing portion B1 is provided on the secondary side with respect to the portion where the cross-sectional area of the flow path is smallest.

In the above embodiment, the inner protruding portion A1 is formed by the inclined surface 33 and the inner surface 34, but the shape of the inner inclined surface is not limited thereto. For example, as modification 2, the stepped portion C1 may be formed by the inner protruding portion A2 as shown in fig. 5. That is, in modification 2, the valve seat portion 30A has the contact portion 31, the upper surface 32, the straight portion 301 extending in the Z direction from the contact portion 31 toward the valve-closing side, the radially extending portion 302 extending radially from the end portion of the straight portion 301 on the valve-closing side toward the inner peripheral side, and the inner surface 34 extending in the Z direction from the inner peripheral side end portion of the radially extending portion 302 toward the valve-closing side. The straight portion 301 extends along the first virtual plane S1, and a portion of the valve seat portion 30A including the radially extending portion 302 and the inner surface 34 is an inner protruding portion A2 protruding inward from the first virtual plane S1. The flat portion 301 and the inner protruding portion A2 constitute a stepped portion C1.

The cross-sectional area of the flow path between the contact portion 31 and the seating portion 423 becomes minimum, and between the corner portion between the radially extending portion 302 and the inner surface 34 and the reduced diameter portion 421, the cross-sectional area of the flow path becomes extremely small, thereby forming the intermediate pressure varying portion B2. The intermediate pressure changing portion B2 can suppress the hunting phenomenon in the same manner as in the above embodiment.

In the above embodiment, the valve seat portion 3 has the inner protruding portion A1, but the valve seat portion may be configured to have the valve opening side protruding portion. For example, as modification 3, as shown in fig. 6 and 7, the valve seat portion 30B may be configured to have a contact portion 31, an inner surface 303 extending in the Z direction from the contact portion 31 toward the valve-closing side, an inclined surface 304 having an inner diameter that increases from the contact portion 31 toward the valve-opening side, and an upper surface 305 extending from an outer peripheral side end portion of the inclined surface 304 toward the outer peripheral side along the XY plane. The portion of the valve seat portion 30B of modification 3, which is composed of the inclined surface 304 and the upper surface 305, is a valve-opening-side protruding portion A3 that protrudes toward the valve opening side from the second virtual surface S2. The inner surface 303 extends so as to overlap with a first virtual plane S1 extending in the Z direction from the contact portion 31. With such valve-opening-side protruding portion A3, an intermediate pressure changing portion B3 is formed between the reduced diameter portion 421 and the inclined surface 304 on the outer peripheral side of the contact portion 31 and the seating portion 423.

The valve-opening-side protruding portion is not limited to include an inclined surface, and may be formed as a stepped portion as in modification 2.

In the above embodiment, the valve body 4 is a needle valve body, but the valve body may have a reduced diameter portion and a seating portion, and may be a ball valve having a spherical portion at the tip end portion, for example. For example, as modification 4, a valve body having a spherical portion 40A may be used as shown in fig. 8. A half area of the spherical portion 40A on the valve closing side is a reduced diameter portion 44 whose outer diameter decreases toward the valve closing side, and a seating portion 441 is provided in the reduced diameter portion 44. In modification 6, the same valve seat portion 3 as in the above embodiment is used.

In the valve body 4 of the above embodiment, the reduced diameter portion 421 has a straight cross section, whereas the reduced diameter portion 44 of the spherical portion 40A of the modification 4 has a convex cross section on the outside and the valve closing side. Even when the reduced diameter portion 44 has such a cross-sectional shape, the jumping phenomenon can be suppressed by forming the inner protruding portion A1 and the intermediate pressure changing portion B1 in the same manner as in the above-described embodiment.

As modification 5, as shown in fig. 9, a spherical portion 40A and a valve seat portion 30A similar to modification 2 may be combined.

The respective configurations (whether or not there is a sealing member, the setting of the primary side and secondary side ports, which of the inner side protruding portion and the valve opening side protruding portion is provided, the shape of the inner side protruding portion or the valve opening side protruding portion, the shape of the valve body, and the like) shown in the above embodiments and modifications 1 to 5 can be appropriately combined. Further, both the inner protruding portion and the valve opening side protruding portion may be provided. In this case, the valve body and the valve seat portion can be in surface contact, but any position of the surface contact becomes the contact portion and the seating portion.

In the above embodiment, the first connection opening 2A for connecting the end joint pipe 11 as the first joint member is provided at the end in the Z direction of the valve housing 2, and the second connection opening 2B for connecting the side joint pipe 12 as the second joint member is provided at the side surface of the valve housing 2.

The embodiments of the present invention have been described in detail above with reference to the drawings, but the specific configuration is not limited to the above embodiments, and design changes and the like within the scope of the gist of the present invention are also included in the present invention.

Claims (7)

1. A pressure regulating valve is characterized by comprising:

a valve housing having a first connection opening for connection of the first joint member and a second connection opening for connection of the second joint member;

a valve seat portion provided in the valve housing and having a valve port communicating with the first joint member;

a valve element that changes the opening degree of the valve port by moving toward the valve opening side or the valve closing side in the axial direction of the valve port; and

A pressure-sensitive member which is housed in a housing portion of the valve housing and which communicates with the first joint member or the second joint member, and which applies a force in the axial direction to the valve element in accordance with a pressure in the housing portion,

A valve chamber communicating with the second joint member is formed around the valve housing and the valve body,

The valve body has a reduced diameter portion having an outer diameter that decreases toward the valve closing side, and a seating portion provided in the reduced diameter portion and seated on the valve seat portion,

The valve seat portion has a contact portion that contacts the seating portion, and has at least one of an inner protruding portion that protrudes toward an inner peripheral side than a first virtual surface extending from the contact portion in the axial direction, and a valve opening side protruding portion that protrudes toward the valve opening side than a second virtual surface extending from the contact portion in the radial direction.

2. The pressure regulating valve of claim 1, wherein,

The valve seat portion has the inner protruding portion or the valve opening side protruding portion on the primary side with respect to the contact portion.

3. The pressure regulating valve according to claim 1 or 2, wherein,

The inner protruding portion includes an inclined surface whose inner diameter decreases from the contact portion toward the valve-closing side, or the valve-opening side protruding portion includes an inclined surface whose inner diameter increases from the contact portion toward the valve-opening side.

4. The pressure regulating valve according to claim 1 or 2, wherein,

The valve seat portion has a stepped portion formed of a straight portion extending from the contact portion along the first virtual plane or the second virtual plane, and an extension portion extending continuously from the straight portion in the radial direction or the axial direction.

5. The pressure regulating valve according to claim 1 or 2, wherein,

The valve body is a needle valve body integrally having a rod-shaped portion and a needle tip portion provided at one end of the rod-shaped portion and having the seat portion and the diameter-reduced portion.

6. The pressure regulating valve according to claim 1 or 2, wherein,

The valve body has a spherical portion formed in a spherical shape and provided with the seating portion and the diameter-reduced portion.

7. The pressure regulating valve according to claim 1 or 2, wherein,

And a sealing member that guides the valve body in the axial direction and that divides a space that is located on the valve opening side and communicates with the housing portion and a space that is located on the valve closing side and communicates with the second joint member,

The first joint member is a primary-side joint member and communicates with the housing portion,

The sealing member is configured to apply pressure from the valve opening side to the second joint member and from the valve closing side to the first joint member,

In the valve body, the pressure of the second joint member acts between the seal member and the contact portion, and the pressure of the first joint member acts at a position closer to the valve opening side than the seal member and a position closer to the valve closing side than the contact portion.