JP2013068329A - Valve seat body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To match to usage when constituting a piston part and a base valve part in a hydraulic shock absorber, naturally and to prevent damping force from becoming high suddenly even when the piston speed exceeds 1 m/sec, in the hydraulic shock absorber.SOLUTION: Hydraulic fluid is permitted to flow toward an inflow part for opening an upstream side end in a one-way passage 1a from a radial opening which is emerged as an open-type valve seat part 1c for separating/seating a relief valve 3 while the upstream side end in the one-way passage 1a is opened causes the relief valve 3 to be seated on a valve seat surface, one end surface defining the inflow part is a flat surface 1g without a step, and meantime, a reference hole 1i is formed which has a diameter larger than the one-way passage 1a and is opened to the one end surface and the other end surface, an inner diameter adjusting body 5 is disposed which has a through hole 5a in place of the one-way passage in a shaft center in the reference hole 1i, a depressed part 1j is formed which has a step between an upper end of the inner diameter adjusting body 5 and the upstream side end in the reference hole 1i, and the through hole 5a is opened at a bottom of the recess 1j.

Description

The present invention relates to a valve seat body, and more particularly to an improvement of a valve seat body suitable for use in a piston body constituting a piston portion in a hydraulic shock absorber and a disk body constituting a base valve portion.

There have been various proposals for a valve seat body suitable for use in a piston body constituting a piston portion in a hydraulic shock absorber and a disk body constituting a base valve portion. In this proposal, the damping force generated by the valve facing the downstream end in the passage formed in the valve seat body is stabilized.

That is, the proposal disclosed in Patent Document 1 relates to a piston body that constitutes a piston portion in a hydraulic shock absorber, and this piston body is a rod that is on one side inside a cylinder body that is a container that contains hydraulic oil as a working fluid. A side chamber and a piston side chamber which is the other side are defined.

The piston body has an extension side port as one passage and a pressure side port as the other passage that open on one end surface facing the rod side chamber and open on the other end surface facing the piston side chamber. Has a leaf valve that closes the downstream side end of the pressure side port so that it can be opened, and has a leaf valve that closes the downstream side end of the extension side port so that it can be opened. It becomes.

Further, for example, the piston body is formed in a flower cross shape on one end surface which is an upper end surface in FIG. 4A and opens the downstream end of the pressure side port 1b as shown in FIG. 4B. The closed type is formed in a closed state by allowing the leaf valve 3 (see FIG. 4A) to be seated and forming an outflow portion that allows the hydraulic oil to flow out from the piston side chamber via the pressure side port 1b. Appearing between the valve seat 1d and the adjacent one of the closed type valve seat 1d to open the upstream end of the extension port 1a and to seat the leaf valve 3 (see FIG. 4A). And an open-type valve seat portion 1c that is defined in an open state having an opening in the radial direction and forms an inflow portion that allows inflow of hydraulic oil from the rod side chamber (not shown).

Incidentally, this open type valve seat portion 1c is shown in the figure, and is formed so that a valve seat surface (not shown) as a top end surface on which the leaf valve 3 is seated is substantially U-shaped in plan view. Therefore, when the leaf valve 3 is seated on the valve seat surface, the inflow portion where the upstream end of the extension port 1a is opened from the opening that opens radially toward the outer peripheral side of the piston body 1. Allow inflow of hydraulic oil toward

And the end surface in the piston body 1 which forms the inflow part in this open | release type valve seat part 1c has what is called the shallow entrance side part 1e and so-called deep back side which continue through the level | step difference d, as shown to FIG. 4 (A). And an upstream end of the extension side port 1a is opened in the back side portion 1f.

Therefore, when the hydraulic oil from the rod side chamber flows into the extension side port 1a, the hydraulic oil does not "contract" at the extension side port 1a and is generated by the leaf valve 2 which is an extension side damping valve. Damping force is stabilized.

That is, although not shown, the one end surface of the piston body 1 that forms the inflow portion in the above-described open type valve seat portion 1c does not have the shallow entrance side portion 1e, and is the same as the deep level of the back side portion 1f. In the case of shaping, the opening area is increased so as to allow the inflow of hydraulic oil from the rod side chamber by the amount that does not have the entrance side 1e.

Therefore, for example, when the piston speed is as high as 1 m / sec, the hydraulic oil stays at a high speed and flows into the expansion side port 1a. In the expansion side port 1a, the flow of the hydraulic oil is disturbed. The flow is expressed, and the amount of hydraulic fluid passing through the leaf valve 2 is not stabilized by this “contracted flow”, and the generated damping force is made unstable.

Effective in preventing the occurrence of this “constricted flow” is the proposal disclosed in the above-mentioned Patent Document 1, that is, one end surface of the piston body 1 forming the inflow portion of the open type valve seat portion 1c is continuous through the step d. It has a shallow entrance side part 1e and a deep back side part 1f, so that high-speed hydraulic oil from the entrance side part 1e that reduces the opening area is allowed to flow out to the back side part 1f that increases the opening area. It is to reduce the oil flow rate.

JP 2005-36886 (Abstract, see paragraph 0018 in the specification, FIG. 1 and FIG. 2)

However, in the proposal disclosed in Patent Document 1 described above, basically, there is no problem as long as the piston speed is in a region not exceeding 1 m / sec. Considering the fact that it is used in a vehicle, there are concerns about minor problems.

That is, the proposal disclosed in Patent Document 1 described above is effective based on the assumption that the piston speed in a hydraulic shock absorber mounted on a vehicle does not exceed 1 m / sec.

In other words, as long as a vehicle on the assumption of paved good road travels normally on a good road, it is not easily assumed that the piston speed exceeds 1 m / sec in the hydraulic shock absorber mounted on the vehicle. However, even if the vehicle travels on a bad road at high speed, or even on a good road, if the vehicle climbs on a curb or climbs over a speed breaker, the piston speed will exceed 1 m / sec. 1.5 to 2.0 m / sec.

At this time, according to the proposal disclosed in Patent Document 1 described above, the shallow inlet side portion 1e in which one end surface of the piston body 1 forming the inflow portion of the open type valve seat portion 1c is continuous through the step d. And the deep back side 1f, so that the high-speed hydraulic oil flows out from the entrance side 1e, which reduces the opening area, to the back side 1f, which increases the opening area. Although this mitigates, this becomes a problem that expresses vehicle body vibration due to high-speed damping.

That is, when high-speed hydraulic oil flows into the expansion side port 1a, the hydraulic oil is once squeezed at the shallow inlet side 1e on the upstream side of the expansion side port 1a. It is feared that the damping force of the port characteristic due to the above does not occur as it is, that is, the damping force of the orifice characteristic is generated, and that the damping force is rapidly increased in the region where the piston speed exceeds 1 m / sec.

The present invention was devised in view of the above-described circumstances, and the object of the present invention is, of course, suitable for use in configuring a piston portion and a base valve portion in a hydraulic shock absorber. Even if the piston speed exceeds 1 m / sec in the shock absorber, the damping force at that time is not increased rapidly, for example, to improve the riding comfort in a vehicle equipped with the hydraulic shock absorber. An object of the present invention is to provide a valve seat body that is optimal for maintaining and expecting improvement in versatility of the hydraulic shock absorber.

In order to achieve the above-described object, the configuration of the valve seat body according to the present invention is basically accommodated in a container that contains a working fluid to define one side and the other side. And having one passage and the other passage that open to the other end surface facing the other side and allow communication between the one side and the other side. A valve seat body constituting a piston body in a piston portion or a disc body in a base valve portion having a leaf valve for releasably closing each downstream side end of the other passage, wherein the one end face is downstream of the other passage. By opening the side end and seating the leaf valve, a closed state is defined to form an outflow portion that allows the working fluid to flow out from the other side through the other passage. Appearing next to each other and opening the upstream end of the one passage and making the leaf valve seated to appear in the radial direction. A valve seat body having an open type valve seat portion that is defined by an opening and that forms an inflow portion that allows inflow of a working fluid from one side, and the inflow in the open type valve seat portion. While the one end surface defining the portion is a flat surface having no step, a reference hole that opens to the one end surface and the other end surface is formed while being larger in diameter than the one passage. In addition, an inner diameter adjusting body having a through hole in place of the one passage is disposed in the reference hole in the reference hole, and a step is formed between the upper end of the inner diameter adjusting body and the upstream end of the reference hole. This recess forms a concave The bottom parts is opened the through hole, characterized by comprising.

Therefore, in the present invention, since the end surface defining the inflow portion is a flat surface having no step in the inflow portion of the open type valve seat portion, the inflow portion has a step. Therefore, as compared with the situation where the flow rate of the working fluid is reduced, the situation where the flow rate of the working fluid flowing into the inflow portion is reduced is not generated, and there is no need to worry about the generation of a high damping force.

And in this invention, while making the diameter larger than said one channel | path, it forms the reference hole opened to said one end surface and said other end surface, and it is said one side to an axial center part in this reference hole An inner diameter adjusting body having a through hole in place of the passage is disposed, a concave portion having a step is formed between the upper end of the inner diameter adjusting body and the upstream end of the reference hole, and the bottom of the concave portion When the hydraulic fluid that has flowed into the inflow portion of the open type valve seat portion flows into the one passage, the hydraulic fluid does not flow into the one passage while maintaining its flow rate, but is recessed. Since the fluid flows into the through-holes through the section, the flow rate of the hydraulic oil in the one passage is relaxed. Therefore, the contracted flow is not expressed in the one passage where the working fluid in which the flow velocity is relaxed flows, and the downstream side of the one passage Leaf bar that closes the end to open and close To stabilize the damping force caused by blanking.

As a result, in this valve seat body, not only when the piston speed is in a region not exceeding 1 m / sec, but also in the region where the piston speed exceeds 1 m / sec, a desired damping force is generated. For example, the ride comfort in a vehicle equipped with a hydraulic shock absorber using the valve seat body is properly maintained.

Further, the inner diameter adjuster disposed in the reference hole basically has a through hole in the shaft core, and the length can be freely selected as long as it does not hinder the generation of port characteristics.

The piston body by one Embodiment of this invention is shown, (A) is a half hook longitudinal cross-sectional view, (B) is a half hook top view. It is a semi-rotary longitudinal cross-sectional view which shows the piston body by other Embodiment of this invention. It is a figure which shows the piston body concerning another reference example of this invention similarly to FIG. It is a figure which shows the piston body of a prior art example similarly to FIG.

Hereinafter, the present invention will be described based on the illustrated embodiment. The valve seat body according to the present invention is not illustrated in detail in the illustrated embodiment, but is similar to the proposal disclosed in Patent Document 1 described above. The piston body 1 is configured to be slidable in a cylinder body serving as a container for accommodating hydraulic oil as a working fluid in the hydraulic shock absorber.

At this time, the piston body 1 is held at the tip of a rod body 4 that is inserted into the cylinder body so as to be able to appear and retract, and the cylinder body is provided with a rod side chamber (not shown) on one side which is the upper side in FIG. 1) and a piston side chamber (not shown) which is the other side which is the lower side in FIG. 1 (A).

As shown in FIG. 1, the piston body 1 opens to the other end surface which is the lower end surface in FIG. 1A and the one end surface which is the upper end surface in FIG. The rod-side chamber and the piston-side chamber have an extension side port 1a that allows communication between the rod side chamber and a piston side chamber, and a pressure side port 1b that serves as the other passage (see (B) in FIG. 1).

The extension side port 1a closes the downstream end, which is the lower end in FIG. 1 (A), so that it can be opened and closed by a leaf valve 2 shown in phantom in the drawing, and the compression side port 1b The downstream end shown is closed so as to be openable and closable by a leaf valve 3 shown by a virtual diagram in FIG.

Incidentally, in the place shown in the figure, the leaf valve 2 is an extension side damping valve, the leaf valve 3 is a compression side valve, and the extension side damping valve is at the time of the extension side operation in which the piston part rises in the cylinder body. A predetermined extension side damping force is generated when the hydraulic oil passes, and the pressure side valve allows the hydraulic oil to pass during the pressure side operation in which the piston portion descends in the cylinder body and accommodates the hydraulic oil in the rod side chamber.

Each leaf valve 2, 3 is formed in an annular shape and is arranged in a manner that the inner peripheral end is fixed and the outer peripheral end is free, and a gap that appears between the valve seat surface described later when each outer peripheral end is bent Allows hydraulic oil to pass through.

Further, when the leaf valve 2 functions as an extension side damping valve, the leaf valve 3 functions as a check valve, and when the leaf valve 3 functions as a pressure side valve, the leaf valve 2 functions as a check valve.

On the other hand, the piston body 1 is formed in a flower cross shape on one end surface which is the upper end surface in FIG. 1A and opens the downstream end of the pressure side port 1b as shown in FIG. 1B. It has a closed valve seat portion 1d that is formed in a closed state by seating the leaf valve 3 and forms an outflow portion that allows outflow of hydraulic oil from the piston side chamber through the pressure side port 1b.

In addition, the piston body 1 appears so as to be sandwiched between the closed valve seat portions 1d, opens the upstream end of the extension port 1a, and seats the leaf valve 3 on the piston body 1. It has an open valve seat portion 1c that is defined in an open state having an opening in the radial direction and forms an inflow portion that allows inflow of hydraulic oil from the rod side chamber (not shown).

As described above, the closed valve seat portion 1d and the open valve seat portion 1c allow the leaf valve 3 to be seated on the valve seat surface, which is the top end face, in a manner in which the outer peripheral end is free by fixing the inner peripheral end.

At this time, the above-described open type valve seat portion 1c is involved in the realization of the present invention, and this open type valve seat portion 1c is shown in the drawing and is a valve seat as a top end surface on which the leaf valve 3 is seated. The surface (not shown) is formed to have a substantially U-shape in plan view. Therefore, when the leaf valve 3 is seated on the valve seat surface, the surface is radially directed toward the outer peripheral side of the piston body 1. Opening (see FIG. 1 (B)) The hydraulic oil from the rod side chamber is allowed to flow into the inflow portion that opens the upstream end of the extension side port 1a through the opening.

That is, in the open type valve seat portion 1c, as shown by an arrow a in FIG. 1A, the hydraulic oil from the rod side chamber opens the upstream end of the expansion side port 1a through the radial opening. It is allowed to flow toward the inflow portion and continue to flow into the extension side port 1a.

The inflow portion in the open valve seat portion 1c is defined by one end surface of the piston body 1, that is, a flat surface having no step d, and this flat surface is used as a reference surface 1g. The upstream end of the extension port 1a is opened.

At this time, the reference surface 1g does not narrow the distance from the lower end surface of the leaf valve 3 that is disposed above and defines the inflow portion, that is, the back side portion 1f shown in FIG. The distance from the lower end surface of the leaf valve 3 in FIG.

That is, the entrance side 1e shown in FIG. 4A has a narrower interval with respect to the lower end surface of the leaf valve 3 than the back side 1f continuous through the step d, that is, the back side 1f. Therefore, when the high-speed hydraulic oil from the rod side chamber flows into this inflow portion, the opening area is once reduced, and therefore the piston speed is 1 m. As described above, high damping force is generated when exceeding / sec.

Therefore, in this invention, in the present invention, the reference surface 1g in the inflow portion that opens the upstream end of the extension side port 1a is at the same level as the above-mentioned back side portion 1f, that is, the reference surface 1g and the leaf The distance between the lower end surface of the valve 3 is set to be the same as the distance between the above-mentioned rear side portion 1 f and the lower end surface of the leaf valve 3.

Therefore, when the piston body 1 is formed, the above-described step d and the entrance side portion continuous through the step d are formed on one end surface of the piston body 1 that defines the inflow portion of the open valve seat portion 1c. 1e and the back side portion 1f are formed as a flat surface, so that, for example, the die removal at the time of molding using a mold is improved, and the finish of the reference surface 1g when the piston body 1 is sintered is improved. To improve.

And since the inflow part in the open type valve seat part 1c which has said reference surface 1g does not have the level | step difference d, when the high-speed hydraulic fluid from a rod side chamber flows in into this inflow part, this inflow part is formed. Therefore, it is possible to realize the generation of the damping force of the port characteristics by the extension side port 1a after the dredging, and suddenly the damping force in the region where the piston speed exceeds 1 m / sec. In other words, the damping force of the orifice characteristic is not generated.

Here, in order to increase the distance between the reference surface 1g and the lower end surface of the upper leaf valve 3, it is assumed that the distance is adjusted to the level of the back side portion 1f shown in FIG. However, instead of this, although not shown, it can be said that the boss 1h (see FIG. 1A) of the piston body 1 can be realized by raising the height.

However, when the boss portion 1h in the piston body 1 is raised to increase the distance between the reference surface 1g and the lower end surface of the leaf valve 3, the piston body 1 in FIG. The length in the axial direction is increased, and accordingly, the length in the axial direction of the piston portion is increased to cause a decrease in effective stroke in the cylinder body.

Therefore, in view of this, as described above, the distance between the reference surface 1g and the lower end surface of the leaf valve 3 is increased in accordance with the level of the rear side portion 1f shown in FIG. In this case, the intended dimensions of the present invention can be embodied with the same dimensions as the piston body 1 that is generally used.

Next, with regard to the expansion side port 1a, in the present invention, the piston body 1 is formed in the piston body 1 and is opened to one end face and the other end face of the piston body 1, that is, the extension. A reference hole 1i having a larger diameter than that of the side port 1a is provided, and the extended side port 1a is formed again in the reference hole 1i.

That is, the conventional expansion side port 1a and the compression side port 1b shown in FIG. 4 described above are formed directly on the piston body 1. At this time, the compression side port 1b is formed to have a large diameter, so However, for the extended side port 1a, precise management of the diameter is required due to the occurrence of port characteristics.

Further, when observing the extended side port 1a, specifically, the diameter dimension changes in units of 0.2 mm, and moreover, it changes in multiple stages of about six stages, and therefore the inventory management of the piston body 1 is not easy.

On the other hand, in the present invention, since the piston body 1 has the reference hole 1i for forming the extended side port 1a after the heeling, when the reference hole 1i is formed, this is larger than the extended side port 1a. In view of the fact that it is formed in the diameter, compared with the case where the above-described conventional extension side port 1a is directly formed in the piston 1, so-called hole formation is made extremely easy and the hole for the piston body 1 is formed. Opening is a one-time operation.

In addition, the piston body 1 of almost all kinds is sintered, but conventionally, it is sintered before forming the expansion side port 1a on the piston body 1, so that the expansion side port 1a is opened. In consideration of the fact that the piercing operation is not easy, the piston body 1 of the present invention can be subjected to a sintering process for the piston body 1 after the large-diameter reference hole 1i is formed. The inconvenience of forming the extended side port 1a in the body 1 can be avoided.

In the present invention, the expansion side port 1a is formed by the inner diameter adjusting body that is lightly press-fitted into the reference hole 1i, i.e., the cylindrical body 5. It has a through hole 5a instead of the extended side port 1a, and is made of, for example, a resin material rich in swelling property.

Since the cylindrical body 5 is made of a resin material having a high swelling property, when the cylindrical body 5 lightly press-fitted into the reference hole 1i comes into contact with the hydraulic oil, the cylindrical body 5 infiltrates the hydraulic oil. The outer periphery is brought into close contact with the inner periphery of the reference hole 1i, and the press-fitted state is maintained in the reference hole 1i.

In addition, the cylindrical body 5 has the same outer diameter and changes the diameter of the through hole 5a formed in the shaft core portion in multiple stages such as the above six stages, and the diameter in the through hole 5a at that time It is assumed that the difference depends on, for example, the coloring difference that appears in the resin material used.

Incidentally, when the through hole 5a is formed in the shaft core portion of the cylindrical body 5, in most cases, molding or use of a drill will be selected. Compared with the case where the piston body 1 is directly formed, it is possible to reduce the manufacturing cost of the parts. Also, the piston body 1 itself can be prepared by one kind, and the inventory management of the piston body 1 is easy. To.

On the other hand, although it is the cylindrical body 5 formed as mentioned above, when this is arrange | positioned at the reference hole 1i, the piston body 1 which the upper end forms the inflow part in the above-mentioned open | release type valve seat part 1c. In FIG. 1 (A), it is a position that is recessed with a step d from the reference surface 1g that is the end surface of the surface.

Accordingly, the reference surface 1g exposes the end of the reference hole 1i having a diameter larger than that of the expansion side port 1a, and the depth based on the step d between the upstream side end of the expansion side port 1a. The circular concave portion 1j (see FIG. 1A) appears.

Therefore, when the hydraulic oil that has flowed into the inflow portion in the open valve seat portion 1c flows into the expansion side port 1a, the hydraulic oil does not flow into the expansion side port 1a while maintaining its flow rate. Since the fluid flows into the expansion side port 1a through the recessed portion 1j having d, the flow rate of the hydraulic oil in the expansion side port 1a is relaxed, and the above-mentioned "constriction flow" is not expressed in the expansion side port 1a. The generated damping force by the leaf valve 2 that closes the downstream end of the side port 1a so as to be openable and closable is stabilized.

As described above, according to the present invention, the upstream end of the extended side port 1a that opens to the inflow portion is located at the downstream side of the extended side port 1a. The rod side chamber is provided with a recessed portion 1j having a step d between the opening end expanded to a larger diameter and the opening end at the downstream side extension port 1a. Since the flow velocity of the working fluid flowing into the inflow portion at a high speed is relaxed by the recessed portion 1j, it flows into the downstream side of the extension side port 1a.

And since the working fluid flows into the downstream side of the expansion side port 1a with the flow velocity reduced, the hydraulic oil does not flow downstream on the expansion side port 1a, and the downstream end of the expansion side port 1a The damping force generated by the leaf valve 2 that is closed so as to be opened and closed is stabilized.

Moreover, since the inflow part in the open type valve seat part 1c which opens the said upstream end by which diameter was expanded does not have the level | step difference d as shown in FIG. 4, the level | step difference d is formed in this inflow part. Thus, a situation in which the flow velocity of the high-speed hydraulic oil flowing into the inflow portion from the rod side chamber is reduced is not expressed.

And since the flow velocity in the high-speed hydraulic fluid which flows into the inflow part in this open | release type valve seat part 1c from a rod side chamber is not restrict | squeezed by this inflow part, the setting by the expansion side port 1a which opens an upstream end to this inflow part Does not hinder the generation of damping force.

As a result, a desired damping force can be generated even when the piston speed exceeds 1 m / sec, as well as when the piston speed does not exceed 1 m / sec. Riding comfort in a vehicle equipped with a hydraulic shock absorber using the vehicle is properly maintained.

In view of the above, the cylindrical body 5 disposed in the reference hole 1i in the piston body 1 basically has a through hole 5a in place of the expansion side port 1a in the shaft core portion. As long as the generation of the characteristics is not hindered, the length is freely selected, and the shape of the downstream side end which is the lower end in FIG. 1A is expanded in a trumpet shape as shown in FIG. It may be formed freely as long as it does not interfere with the predetermined operation of the leaf valve 2, such as being opened.

In addition, the present invention intends to avoid the generation of a high damping force when the piston speed exceeds 1 m / sec, and the leaf valve 2 when the piston speed does not exceed 1 m / sec. Therefore, it is possible to generate a stable damping force.

And as a means for realizing that, the reference surface 1g as the end face of the piston body 1 that defines the inflow portion in the open type valve seat portion 1c does not have the step d, and the flow of hydraulic oil is possible without stagnation. From the viewpoint of reducing the flow rate of the hydraulic oil by providing a recessed portion 1j having a step d at the upstream end of the extension side port 1a, as shown in the reference example of FIG. While having the reference surface 1g which is not a flat surface, it has the concave portion 1j which causes the step d at the upstream end of the extension side port 1a even without the cylindrical body 5 as described above. It is possible to avoid generation of high damping force and stable generation of damping force by the leaf valve 2.

In the above description, the valve seat body according to the present invention is composed of the piston body 1. However, from the intention of the present invention, the valve seat body is not shown, but the valve seat body is a disc body, that is, the bottom of the cylinder body in the hydraulic shock absorber. It may be a disk body that constitutes a base valve portion that is fixedly housed in the end portion and defines a piston side chamber inside the cylinder body and a reservoir outside the cylinder body.

Although not shown in the figure, in this case, instead of the rod body 4, the center rod passes through the shaft core portion of the disk body, and one passage is formed in the disk body so that the compression side damping valve is separated from the downstream end. It is a compression side port to be seated.

It is suitable for use in configuring a piston part and a base valve part in a hydraulic shock absorber that is mounted on a vehicle and absorbs road surface vibrations input to wheels.

DESCRIPTION OF SYMBOLS 1 Piston body 1a which is a valve seat body Expansion side port 1b which is one passage Other pressure side port 1c which is the other passage Open type valve seat part 1d Closed type valve seat part 1g Reference surface 1i which is a flat surface Reference hole 1j Recessed part 2, 3 Leaf valve 4 Rod body 5 Cylindrical body 5a which is an inner diameter adjusting body A through hole instead of the extension side port

Claims (3)

  It is housed in a container that contains the working fluid, defines one side and the other side, opens to one end surface facing the one side and opens to the other end surface facing the other side and A piston body in a piston part having a one-passage and a second-passage that allow communication between one side of the first-passage and the other-side and a leaf valve that closes each downstream end of the one-passage and the other-passage so as to be openable A valve seat body that constitutes a disc body in a base valve portion, wherein the downstream end of the other passage is opened on the one end surface and the leaf valve is seated to define a closed state. A closed-type valve seat portion that forms an outflow portion that allows the working fluid to flow out from the other side through the other passage of the closed-type valve seat portion. On the other hand, the upstream end of the passage is opened, and the leaf valve is seated to define an opening that appears in the radial direction, thereby forming an inflow portion that allows the inflow of the working fluid from the one side. In the valve seat body having the open valve seat portion, the one end surface defining the inflow portion in the open valve seat portion is a flat surface having no step, and the one passage A reference hole that opens on the one end surface and the other end surface while having a larger diameter is formed, and an inner diameter adjuster having a through hole in place of the one passage is provided in the shaft hole in the reference hole. And the valve seat body which forms the recessed part which has a level | step difference between the upper end of this internal diameter adjustment body and the upstream end in said reference | standard hole, and makes said through-hole open to the bottom part of this recessed part.   The valve seat body according to claim 1, wherein the inner diameter adjuster is a suitably thick cylindrical body made of a synthetic resin material rich in swelling, and the cylindrical body is arbitrarily colored.   The valve seat body according to claim 1 or 2, wherein the downstream end portion of the one passage is formed in a trumpet shape.

Images