JPH05272652A - Pressure regulating valve - Google Patents

Abstract

PURPOSE:To provide a pressure regulating valve which can suppress the displace ment in the radial direction of a bellows or valve piece by the action of an inflow fluid, without suppressing the smooth extension/contraction operation of the bellows. CONSTITUTION:A bellows 3 is extended/contracted in the axial direction, i.e., in the valve opening/closing direction by the pressure difference between the inside and outside of the bellows 3, and the valve opening 21 on a fixed valve seat 2 is opened and closed by the spherical valve (valve piece 4) at the top edge of the bellows 3. When the valve opening 21 is opened, the fluid inside a valve piece 1 flows outside through a flow-out hole 16 from the valve opening 21, and the fluid flows in from the outside fluid space through an inflow hole 15. Since the inflow hole 15 is opened in the deflected direction for the centrifugal direction directing to the center axis of the bellows 3, also the direction of the energizing force generated in the case when the fluid which flows from the inflow hole 15 collides with the bellows 3 or spherical valve 4 deflects, and the vibration and curvature in the radial direction of the bellows 3 and spherical valve 4 are suppressed.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a pressure regulating valve.

[0002]

2. Description of the Related Art FIG. 5 shows a bellows type pressure regulating valve disclosed in Japanese Utility Model Laid-Open No. 63-87377. In this valve, a fixed valve seat 2a is fixed in a tubular valve body 1a.
A bellows 3a is arranged above a. Bellows 3
A ball valve holding cylinder (retainer) 9 is fitted to the tip portion 32a of a, and the ball valve holding cylinder 9 holds the ball valve 4a. A spring 6a is arranged in the bellows 3a, and the spring 6a presses the ball valve 4a against the fixed valve seat 2a via the tip portion 32a of the bellows 3a.

In this valve, when the pressure difference acting on the bellows 3a exceeds the urging force of the spring 6a, the valve opens, and when the pressure difference falls below the urging force, the valve closes and the pressure in the valve body 1a is maintained at a predetermined value. To be done.

[0004]

However, in the above bellows type pressure regulating valve, since the inflow pipe 90 is disposed in the centripetal direction with respect to the axial center of the valve body 1a, the inflow pipe 90 moves from the valve body 1a. The fluid flowing into the internal space S collides with the bellows 3a and the ball valve 4a to urge them in the radial direction, that is, in the direction orthogonal to the expansion / contraction direction, to vibrate and bend. If the inflow pipe 90 is arranged further below the positions of the bellows 3a and the ball valve 4a, the fluid urging force can be reduced, but this increases the overall length of the valve body 1a.

In the valve of FIG. 5, the ball valve holding cylinder 9 is slidably brought into close contact with the inner peripheral surface of the valve body 1a to prevent the vibration and bending of the bellows 3a. In order to smoothly open and close the valve, the clearance between the ball valve holding cylinder 9 and the valve body 1a must be secured to some extent, and radial displacement and vibration of the ball valve 4a by this clearance can be prevented. This is not possible, and such displacement and vibration of the ball valve 4a adversely affects the opening and closing of the valve.

The present invention has been made in view of the above problems, and an object thereof is to provide a pressure regulating valve capable of suppressing radial displacement of the bellows and the valve body without inhibiting smooth expansion and contraction of the bellows. There is.

[0007]

The pressure regulating valve of the present invention comprises:
A tubular valve body having an inflow hole, an outflow hole, and an internal space communicating these two holes, a fixed valve seat having a valve hole communicating the both holes and fixed in the valve body, and a base end portion. Is a bellows that is fixed to the valve body and has a tip portion facing the fixed valve seat and a central portion that expands and contracts; and a bellows that is held by the tip end portion of the bellows and that moves toward and away from the fixed valve seat and the valve hole. And a valve body for opening and closing the inflow hole, wherein the inflow hole is formed in the peripheral wall of the valve body at a position close to at least one of the bellows and the valve body,
The inflow hole is opened in a direction deflected with respect to a centripetal direction toward the central axis of the bellows.

[0008]

The bellows expands and contracts in the axial direction, that is, the valve opening and closing direction due to the pressure difference between the inside and outside of the bellows, and the valve body at the tip of the bellows opens and closes the valve hole of the fixed valve seat. That is, when the fluid pressure in the inner space of the valve body increases, the bellows 3 contracts, the valve body opens the valve hole, and the fluid in the inner space flows out from the valve hole to the outside through the outflow hole, whereby the outside fluid flows through the inflow hole. Fluid flows in from the space.

Since the inflow hole is opened in a direction deflected with respect to the centripetal direction toward the central axis of the bellows, the direction of the urging force generated when the fluid flowing from the inflow hole collides with the bellows or the valve body. To deflect. As a result, the radial component force, which is a problem in the radial vibration and bending of the bellows and the valve body, is reduced by the amount of deflection.

[0010]

As described above, in the pressure regulating valve of the present invention, the inflow hole formed in the peripheral wall of the valve body in the vicinity of the bellows or the valve body is deflected with respect to the centripetal direction toward the central axis of the bellows. Since it is opened in the radial direction, the radial component force of the urging force acting on these bellows and valve body due to the fluid flowing in from this inflow hole is reduced, which causes vibration and bending in the radial direction of these bellows and valve body. Can be reduced.

[0011]

【Example】

(Embodiment 1) An embodiment applied to a fuel valve of an ignition type internal combustion engine will be described below with reference to FIG. This fuel valve includes a valve body 1, a fixed valve seat 2 fixed in the valve body 1, a bellows 3 reciprocally housed in the valve body 1, and a ball held by a tip portion 32 of the bellows 3. Valve (disc in the present invention)
4, a claw 5 protruding toward the fixed valve seat 2 along the outer periphery of the ball valve 4 at the tip 32 of the bellows 3 to irremovably surround the ball valve 4, and a bellows 3 disposed in the bellows 3 And a spring 6 for urging the valve in the valve closing direction.

The valve body 1 has a main cylinder 11 having a stepped cylindrical shape with openings at both ends, and a substantially ring-shaped end plate that closes the opening at the large-diameter end (upper end in FIG. 1) of the main cylinder 11. 12 and end plate 12
The pressure introducing cylinder 13 is inserted into the central hole of the pressure introducing cylinder 13. The upper end of the main cylinder 11 is the largest diameter base end cylinder, and the center of the main cylinder 11 is the middle diameter center cylinder.
The lower part of is the smallest tip cylinder part. Further, a fuel inlet (inflow hole in the present invention) 15 is opened in the central tubular portion, while a tip opening of the tip tubular portion serves as a fuel outlet 16.

FIG. 2 is a sectional view taken along the line AA of FIG.
Four fuel inlets 15 are provided in the central cylinder portion of the main cylinder 11.
The inner peripheral surface of No. 1 is pierced in the tangential direction. A fixed valve seat 2 having a valve hole 21 vertically formed in the center thereof is press-fitted in the upper portion of the above-mentioned tip cylindrical portion of the valve body 1. Bellows 3
Both ends open a short axis cylindrical base end portion 31, and a bellows-shaped stretchable portion 33 that hangs downward from the lower end of the base end portion 31 in FIG.
The distal end portion 32 is formed at the lower end of the stretchable portion 33 and shields the lower end opening of the stretchable portion 33. The base end portion 31 is fitted to the lower end portion of the pressure introducing cylinder 13, while the upper end surface of the base end portion 31 is in contact with the lower surface of the end plate 12. An upper portion of the base end portion 31 is a large-diameter flange portion, and the seal ring 14 is arranged between the flange portion and the base end cylinder portion of the main cylinder 11 surrounding the flange portion.

The lower portion of the base end portion 31 is press fitted into the upper end portion of the main cylinder 11 as shown in FIG. The expandable part 33 is the main cylinder 11
It is accommodated in the central tubular portion of the above so as to be vertically movable. The elastic portion 33 has a wall thickness of about 0.2 mm, and the outermost portion of the elastic portion 33 has an outer diameter of about 12 mm.
The clearance between 3 and the inner peripheral surface of the valve body 1 is set to several tens to several hundreds of μm. The tip portion 32 has a short-axis cylindrical shape having a concave portion, and a ball receiving chamber b for receiving the ball valve 4 is recessed upward in FIG. A spring chamber is recessed further upward from the center. The ball valve 4 is housed in the ball receiving chamber b so as to be rotatable, and the spring 51 is housed in the spring chamber. The spring 51 urges the ball valve 4 downward in FIG. 1, that is, in the valve closing direction.

On the lower end surface of the tip portion 32, a tapered half-cylinder shaped claw 5 is provided so as to surround the opening of the ball receiving chamber b, that is, the ball valve 4. The height of the nail 5 is about 1 to 2 mm,
The tip of the pawl 5 is gradually formed to have a smaller diameter to prevent the ball valve 4 from coming off. A spring 6 is accommodated in the bellows 3, the base end of the spring 6 is locked to the pressure introducing cylinder 13, and the tip of the spring 6 is below the tip 32 of the bellows 3 via the receiving plate 61, that is, in the valve closing direction. Is urged to.

FIG. 3 shows the mounted state of this pressure regulating valve. A stepped pressure regulating valve insertion hole 82 is vertically opened at the end of the fuel pipe 8 having a horizontal fuel hole 81 therein, an O-ring is fitted thereinto, the pressure regulating valve is inserted, and the pressure regulating valve is held by a pressing plate 8.
Fix at 3. Intake pressure from an intake manifold (not shown) of the engine is introduced into the pressure introducing cylinder 13. Fuel is supplied to the lateral fuel hole 81 from a fuel pump (not shown). When the pressure regulating valve is opened, the fuel is sucked from the lateral fuel hole 81 into the pressure regulating valve through the fuel inlet port 15, and the fuel is not injected from the pressure regulating valve. It is discharged to the illustrated fuel tank.

Of the above-mentioned components, the pressure introducing cylinder 1
3, the fixed valve seat 2 and the ball valve 4 are made of stainless steel, the bellows 3 are made of PTFE (polytetrafluoroethylene) resin, the seal ring 14 is made of fluororubber, and the other members are made of carbon steel. The order of assembling the valves will be described. First, the ball valve 4 is pushed into the pawl 5 by utilizing the elastic deformation of the pawl 5. Next, the support plate 61 is placed in the bellows 3.
After accommodating the spring 6 and the spring 6, the lower end of the pressure introducing cylinder 13 is press-fitted into the base end 31 of the bellows 3 to form a ball valve side assembly. In addition, the pressure introducing cylinder 13 is previously attached to the end plate portion 12
Has been inserted into.

Next, the fixed valve seat 2 is pressed into the valve body 1.
Next, after inserting the seal ring 14 into the main cylinder 11, the above-mentioned assembly is fitted into the main cylinder 11 and the end portion of the large diameter cylinder portion of the main cylinder 11 is caulked to the outer periphery of the end plate portion 12. Pressure introducing tube 13
Is further fitted into the end plate portion 12 to adjust the set pressure. After that, the pressure introducing cylinder 13 and the end plate 12 are fixed by welding to complete the assembly.

Next, the production of the bellows 3 will be described. The bellows 3 is formed by preparing a cylindrical body made of PTFE resin, first cutting the outer peripheral surface with a lathe, then clamping the outer peripheral surface with a split cylindrical chuck and cutting the inner peripheral surface. To do. Of course, bellows 3
May be formed by resin molding technology instead of cutting.
As the material of the bellows 3, the PTFE resin is adopted in the above-mentioned embodiment, but other fluororesin having the same characteristics as that and excellent in moldability, for example, ETFE (polyethylene tetrafluoroethylene) may be adopted. When the bellows 3 with the claws 5 is manufactured by such die molding, since the tip of the claws 5 has a small diameter, the die member inserted into the claws 5 is axially oriented. It is forced.

Next, the operation of this fuel valve will be described. When the intake pressure of the engine introduced from the intake manifold to the pressure introducing cylinder 13 is high, the sum of the intake pressure acting on the bellows 3 and the biasing force of the spring 6 is introduced from the fuel inlet 15 to the bellows 3. As the fuel pressure in the acting fuel piping system becomes larger, the bellows 3 expands, the ball valve 4 is pressed against the fixed valve seat 2, and the valve hole 21 is closed.
Due to this closing, fuel leakage from the valve body 1 to the fuel tank (not shown) is prohibited, and the pressure of the fuel piping system rises corresponding to the intake pressure of the engine.

Pressure introducing cylinder 13 from intake manifold
When the intake pressure of the engine introduced into the engine becomes low and the sum of the intake pressure acting on the bellows 3 and the urging force of the spring 6 becomes smaller than the fuel pressure acting on the bellows 3, the bellows 3 contracts and the ball valve 3 4, the valve hole 21 is opened away from the fixed valve seat 2, and this valve opening causes the fuel to escape from the valve body 1 to a fuel tank (not shown). As a result, the pressure of the fuel piping system becomes the intake pressure of the engine. Correspondingly decreases.

In the pressure regulating valve of this embodiment described above, the fuel inlet 15 is pierced in the tangential direction of the inner peripheral surface of the valve body 1 (in particular, the main cylinder 11 thereof). Although the inflowing fuel forms a swirl (vortex) inside the main cylinder 11, the component force that urges the bellows 3 or the ball valve 4 in the radial direction thereof is significantly reduced. Therefore, problems such as the bellows 3 or the ball valve 4 being displaced, vibrating, and curving in the radial direction to hinder the expansion and contraction of the bellows 3 and the contact surface position between the ball valve 4 and the fixed valve seat 2 being displaced are eliminated. be able to.

Further, in this embodiment, as shown in FIG. 4, since the base end portion 31 of the bellows 3 is press-fitted into the upper end portion of the main cylinder 11, the axis of the bellows 3 and the axis of the main cylinder 11 can be easily arranged. The fixed valve seat 2 and the ball valve 4 which are press-fitted into the main cylinder 11 can be easily matched with each other. That is, if the base end 3 of the bellows 3 as in this embodiment
When 1 is not press-fitted into the main cylinder 11, the centering of the bellows 3 is determined by the pressure introducing cylinder 13, and the pressure introducing cylinder 13 is accurately aligned with the separate valve body 1. It will increase the effort.

It is of course possible to integrate the fixed valve seat 2 with the valve body 1.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a fuel pressure regulating valve to which the present invention is applied,

2 is a sectional view taken along the line AA of FIG.

3 is a partial cross-sectional view showing the mounting of the pressure regulating valve of FIG. 1,

FIG. 4 is a partially enlarged sectional view of FIG.

FIG. 5 is a sectional view of a conventional pressure control valve.

[Explanation of symbols]

Reference numeral 15 is an inflow port, 16 is an outflow port, 1 is a valve body, 21 is a valve hole, 2 is a fixed valve seat, 32 is a tip portion of the bellows 3, 4 is a ball valve (valve body), and 5 is a claw.

Claims (1)

[Claims] 1. A fixed valve seat having a tubular valve body having an inflow hole, an outflow hole, and an internal space communicating with both of these holes, and a valve hole communicating with the both holes, and being fixed in the valve body. A bellows having a base end fixed to the valve body and a tip end facing the fixed valve seat, and a central portion expanding and contracting; and a bellows held by the tip end of the bellows and contacting the fixed valve seat by expansion and contraction of the bellows. A valve body that separates and opens the valve hole, wherein the inflow hole penetrates the peripheral wall of the valve body at a position close to at least one of the bellows and the valve body, The pressure regulating valve, wherein the inflow hole is opened in a direction deflected with respect to a centripetal direction toward the central axis of the bellows.