JP3779408B2 - Valve body retention mechanism - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a holding mechanism for a valve body, and more specifically, a recess that is a part of a fluid passage is formed at an end of a support, and is slidably fitted into the recess, and the bottom of the recess The valve body is provided with a valve body that can be attached to and detached from the valve seat, and a spring that has one end engaged with the valve body and the other end supported on the support side.
[0002]
[Prior art]
As this type of prior art, for example, Utility Model Registration No. 2504332 is cited. This publication describes a pressure regulator that is used in a compressed air supply system in an air brake device mounted on a large vehicle or the like and controls loading and unloading of a compressor. A valve body for communicating and blocking the flow of compressed air between the air tank and the compressor is provided at one end opening of the piston slidably inserted into the cylinder chamber of the pressure regulator. This will be described with reference to FIG.
[0003]
A recess 2 is formed at one end opening of the piston 1, and the bottom of the recess 2 serves as a valve seat 3 on which the valve body 4 can be seated. The valve body 3 is integrally provided with a guide portion 6 extending toward the peripheral wall of the recess 2 so that the valve body 4 can move along the peripheral wall of the recess 2. The valve body 4 has one end engaged with the guide portion 6 and the other end urged toward the valve seat 3 by a spring 5 supported on the piston 1 side, and compression of the air tank communicating with the recess 2 Until the air reaches a predetermined pressure, the valve is closed as shown in the figure. However, when the compressed air in the air tank exceeds a predetermined pressure, the piston 1 moves upward in the figure relative to the valve stem 8 fixed to the stationary portion (cylinder body), and the valve body 4 and the valve stem 8 Are brought into contact with each other, and the valve body 4 is separated from the valve seat 3 so that the recess 2 communicates with the communication passage 9 communicating with the compressor side. As a result, the air pressure of the air tank is supplied to the compressor, the built-in unloader valve is opened, and the compressor is unloaded.
[0004]
[Problems to be solved by the invention]
Regarding the holding mechanism for the valve body 4 according to the conventional example, the retainer 7 supported on the piston 1 side is attached to an annular groove 10 formed in the peripheral wall of the recess 2. Therefore, in this conventional example, it is necessary to form the annular groove 10 by machining after the piston 1 is molded. However, performing this machining takes time and leads to a decrease in productivity. Therefore, it is conceivable to eliminate the machining for forming the annular groove 10, and as a means thereof, the piston is molded from resin, and the outer peripheral end of the retainer is directly pressed and positioned and fixed to the peripheral wall of the recess, It is conceivable to engage the other end of the spring with this retainer.
[0005]
However, with this means, it is necessary to consider the draft angle of the mold for molding the piston. This draft increases as the inner diameter of the recess is the same as or close to the opening of the recess. Therefore, when the outer peripheral end of the retainer is directly pressed against the peripheral wall of the recess, the position of the retainer moves to the opening side of the recess over time, and there is a possibility that the retainer may fall out of the recess. Therefore, it is conceivable that the position of the retainer with respect to the piston changes, and the valve body engaged with the spring cannot be positioned.
[0006]
The present invention has been made in view of the above-mentioned problems, omits machining for supporting the retainer after forming a support such as a piston, and reliably positions the retainer over a long period of time, keeping the biasing force of the spring constant. It is an object to provide a holding mechanism for a valve body that can hold a body.
[0007]
[Means for Solving the Problems]
The above problem is that a recess which is a part of the fluid passage is formed at the end of the support, and is slidably fitted into the recess, and is attached to and detached from the valve seat formed at the bottom of the recess. In a valve body holding mechanism including a seatable valve body, and a spring having one end engaged with the valve body and the other end supported on the support body side, the opening end of the recess is opposed to the opening. A groove is provided that penetrates in the radial direction of the recess, and the width of the groove is formed such that the bottom side of the groove is larger than the opening side through the step portion and supports the other end side of the spring. The retainer has a main part that faces the recess and contacts the spring, and a protrusion that extends radially outward of the main part. Solved by a holding mechanism for a valve body, which has a claw portion that is fitted into a groove and engages with the stepped portion.
[0008]
First, align the protrusion of the retainer with the groove at the open end of the recess to bring the claw into contact with the step, and then elastically deform the claw and push the protrusion toward the bottom of the groove to groove the protrusion. The claw portion is engaged with the step portion. In this way, the step portion and the claw portion can be easily engaged, and the positional relationship between the retainer and the support, that is, the retainer and the open end of the recess is not changed, and the valve body is not changed. The setting of the biasing force of the spring can be made constant. In addition, since the groove penetrating in the radial direction of the recess with respect to the opening is formed integrally with the support body when the support body is formed, machining for retaining the retainer after the support body formation may be omitted. it can.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the support mechanism of the valve body by embodiment of this invention is demonstrated. Therefore, in the present embodiment, the flow of compressed air between the air tank and the unloader valve that controls the loading and unloading of the compressor is provided and blocked at the piston one end opening inside the pressure regulator as in the conventional example. A mechanism for holding the valve body for this purpose will be described.
[0010]
FIG. 1 shows a pressure regulator according to this embodiment. The piston 17 as a support is made of resin, and seal rings 26 and 27 are attached to the outer periphery of the piston 17 so as to be slidably inserted into the inner hole 16a of the main body 16, and the pressure chamber 40 and the communication chamber are inserted into the main body 16. 41 and the atmospheric chamber 42 are defined. The main body 16 is formed with a first port 18 that communicates with an air tank (not shown) and a second port 20 that communicates with a compressor (not shown). The first and second ports 18 and 20 are respectively connected to a filter unit 19. , 21 communicates with the pressure chamber 40 and the communication chamber 41. A precompressed spring 24 is disposed between the piston 17 and the opening side of the main body 16. One end of the spring 24 is supported by the spring receiving member 22 contacting the piston 17 and the other end is supported by the opening of the main body 16. The spring receiving member 23 that is in contact with the stopper member 25 is engaged with each other. As a result, the piston 17 is urged downward in the figure, but takes the air pressure of the air tank on the pressure chamber 40 side, and therefore takes the non-operating position shown in the figure.
[0011]
A through hole 44 is formed in the piston 17 in its axial direction, and a valve rod 28 is slidably inserted into the through hole 44 via a seal ring 29. The valve rod 28 is urged toward the atmosphere chamber 42 by the spring member 30, but is in a state illustrated by the bolt member 31 in which the head portion 31 a abuts the end of the valve rod 28 on the atmosphere chamber 42 side. ing. The bolt member 31 is screwed to the spring receiving member 23, and the nut member 32 is screwed to the screw portion 31b. That is, the urging force of the spring 24 is set by tightening the nut member 32. Furthermore, the opening of the main body 16 is covered with a lid member 33 that is screwed into the end portion of the screw portion 31 b of the bolt member 31.
[0012]
A recess 43 is formed at the end of the piston 17 on the pressure chamber 40 side as shown in detail in FIG. The recess 43 has a stepped shape whose bottom side is smaller in diameter than the opening end surface, and includes metal guide portions 35, 35, 35, 35 that are slidable with respect to the peripheral wall. A valve body 34 that can be seated and separated is fitted into an annular valve seat 39 formed at the bottom. As shown in FIG. 4, the guide portions 35, 35, 35, 35 are inserted into the side peripheral surface of the valve body 34 and extend in all directions. One end of a spring 36 that urges the valve body 34 toward the valve seat 39 is engaged with the guide portion 35, and the other end is fixed to the open end of the recess 43 as will be described later. The retainer 37 is supported.
[0013]
As shown in FIGS. 4 to 6, the retainer 37 has an annular main portion 37a having an outer shape substantially equal to the opening of the recess 43, and a pair of protrusions 37b and 37b extending radially outward of the main portion 37a. Have. The main portion 37a faces the recess 43 and supports the other end side of the spring 36. Further, claw portions 37c and 37c formed by bending the projection 37b with respect to the projection 37b are processed by pressing. On the other hand, as shown in FIG. 2 to FIG. 4, a pair of grooves 46, 46 penetrating in the radial direction of the recess 43 are provided on the opening side of the recess 43. The bottom 47 side is formed larger than the opening side through the stepped portion 48. These grooves 46, 46 are formed together with the piston 17 by a mold that is pulled out in the radial direction of the recess 43.
[0014]
Therefore, when the retainer 37 is attached to the opening side of the recess 43, as shown in FIG. 7A (only one side), first, the protrusion 37b of the retainer 37 is aligned with the groove 46 and the claw portions 37c, 37c are stepped. It abuts on the part 48. Next, the claw portions 37 c and 37 c are elastically deformed, and the projecting portion 37 b is pushed toward the bottom portion 47 of the groove 46. 7B, the protrusion 37b of the retainer 37 is fitted into the groove 46, and the claw portions 37c and 37c are engaged with the stepped portion 48. Thereby, the retainer 37 is positioned and fixed to the opening end of the recess 43.
[0015]
As described above, according to the present embodiment, since the grooves 46 and 46 formed at the opening end of the recess 43 are formed together when the piston 17 is molded, in order to support the retainer 37 after the piston molding. Machining can be omitted, and the claw portion 37c of the retainer 37 and the stepped portion 48 of the groove 46 can be easily engaged, so that the retainer 37 can be assembled to the recess 43 very much. Can be easy. Further, since the positional relationship between the retainer 37 and the recess 43 can be reliably maintained, the urging force of the spring 36 can be kept constant to hold the valve body 34.
[0016]
According to the present embodiment, the retainer 37 can be easily formed because the claw portion 37c of the retainer 37 is simply bent with respect to the protrusion 37b by press working. Further, the recess 43 has a stepped shape in which the bottom side has a smaller diameter than the opening end surface, and the guide body 35, 35, 35, 35 extends to the valve body 34 from the side peripheral surface toward the peripheral wall of the recess 43. Therefore, the valve body 34 can be easily fitted into the recess 43, and the valve body 34 can be smoothly slid in the recess 43.
[0017]
Next, the operation of the pressure regulator 15 configured as described above will be described with reference to FIG. When the internal pressure of the air tank becomes equal to or higher than a predetermined pressure due to the loading action of the compressor (not shown), the internal pressure of the pressure chamber 40 also rises with reference to FIG. 1 and moves the piston upward against the urging force of the spring 24. The valve body 34 moves slightly upward with the movement of the piston 17, but its movement is restricted by contacting the valve rod 28 fixed to the main body 16 side. When the piston 17 further rises, the valve body 34 is separated from the valve seat 39, whereby the recess 43, that is, the pressure chamber 40 and the communication chamber 41 communicate with each other via the communication passage 38, and the air pressure in the pressure chamber 40 is increased. Is supplied to an unloader valve (not shown) for controlling the loading and unloading of the compressor through the second port 20. As a result, the compressor performs an unloading action, and the supply of compressed air to the air tank is stopped. Thereafter, the piston 17 descends to the non-operating position shown in the figure again by the urging force of the spring 24 due to a decrease in the internal pressure of the pressure chamber 40, and the pressure chamber 40 and the communication chamber 41 are disconnected to load the compressor again. Let it be done. Thereafter, in the same manner, the piston 17 repeatedly moves up and down due to fluctuations in the internal pressure of the pressure chamber 40, and the valve body 34 at this time is repeatedly attached to and detached from the valve seat 39 to keep the air pressure in the air tank at a predetermined pressure.
[0018]
Therefore, according to the present embodiment, a constant urging force of the spring 36 can be always applied to the valve body 34 without causing a change in the urging force of the spring 36 due to a change in the position of the retainer 37, so that a long-term Thus, the stable operation performance of the pressure regulator 15 can be maintained.
[0019]
The embodiment of the present invention has been described above. Of course, the present invention is not limited to this, and various modifications can be made based on the technical idea of the present invention.
[0020]
For example, in the above embodiment, the main portion 37a of the retainer 37 is formed in an annular shape. Instead, as shown in FIG. 8, the main portion 57a of the retainer 57 has an outer shape substantially equal to the opening of the recess 43. While forming in the shape of a disk having a shape, a plurality of large and small holes 58, 59, 60 that serve as a passage for fluid such as compressed air may be formed in the main portion 57a. The protrusions 57b and the claw portions 57c are formed in the same manner as described above. Further, the main part of the retainer is not necessarily limited to a circular shape, and the present invention can be applied to a shape that crosses the opening of the recess 43, for example, a rod shape or a strip shape.
[0021]
In the above embodiment, the application example to the pressure regulator has been described. Of course, the present invention is not limited to this, and the present invention can be applied to various fluid pressure devices, and various shapes of valve bodies. It is also applicable to. For example, it can be applied to the center valve holding mechanism of the center valve type master cylinder, the holding mechanism of the valve body in the flow path switching valve, and the poppet type valve body holding mechanism of the hydraulic pressure control valve that controls the brake fluid pressure It is.
[0022]
【The invention's effect】
As described above, according to the valve body holding mechanism of the present invention, machining for supporting the retainer in the recess of the support body can be omitted, and the claw portion of the retainer and the recess opening end can be omitted. Since the engagement with the step portion of the groove can be easily performed, the assembly of the retainer to the recess can be made very easy. Further, since the positional relationship between the retainer and the recess can be reliably maintained, the urging force of the spring can be kept constant and the valve body can be held.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view in which a valve body holding mechanism according to an embodiment of the present invention is applied to a pressure regulator.
FIG. 2 is an enlarged view of a main part in FIG.
3 is a half sectional side view in the direction of line [3]-[3] in FIG. 2;
4 is an arrow view in the direction [4]-[4] in FIG. 2;
FIG. 5 is a front view of the retainer in the embodiment of the present invention.
FIG. 6 is a side view of the same.
FIGS. 7A and 7B are side views for explaining the operation, in which A shows a state immediately before the retainer is assembled, and B shows a state after the assembly.
FIG. 8 is a front view showing the modification.
FIG. 9 is a cross-sectional view of a main part showing a conventional valve body holding mechanism.
[Explanation of symbols]
15 Pressure regulator 16 Body 17 Piston (support)
24 Spring 34 Valve body 35 Guide part 36 Spring 37 Retainer 37a Main part 37b Projection part 37c Claw part 39 Valve seat 43 Recess 46 Groove 47 Bottom part 48 Step part

Claims (4)

A recess that is part of the fluid passage is formed at the end of the support, and is slidably fitted into the recess, and can be separated from and seated on a valve seat formed at the bottom of the recess. And a holding mechanism for the valve body including a spring that has one end engaged with the valve body and the other end supported on the support side.
A groove that penetrates the opening in the radial direction of the recess is provided at the opening end of the recess, and the groove width is formed such that the bottom side of the groove is larger than the opening side through the stepped portion. And a retainer for supporting the other end of the spring. The retainer has a main part that faces the recess and abuts the spring, and a protrusion that extends radially outward of the main part. The valve body holding mechanism is characterized in that the protrusion has a claw portion that is fitted into the groove by elastic deformation and engages with the stepped portion. The retainer has an outer shape substantially equal to the opening of the recess, or a shape that crosses the opening, and a shape in which the claw is bent with respect to the protrusion, and a press The valve body holding mechanism according to claim 1, wherein the valve body holding mechanism is processed by processing. The recess has a stepped shape whose bottom side has a smaller diameter than the opening end surface, and the valve body extends from the valve body toward the peripheral wall of the recess and is guided to the peripheral wall on the bottom small diameter side. The valve body holding mechanism according to claim 1, wherein a guide portion is formed. The support body is a piston slidably inserted into the main body, and receives fluid pressure at one end side of the piston where the recess is formed, and urges the piston to the non-operating position at the other end side. When the piston is in the non-operating position in response to the force of the spring acting on the valve body, the passage of the fluid is blocked by the seating of the valve body on the valve seat, and the piston is moved against the urging force of the spring. The valve body according to any one of claims 1 to 3, wherein the valve body is applied to a pressure regulator that opens the fluid passage when the valve body is separated from the valve seat. Retention mechanism.

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