JP2848271B2 - Check valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a check valve using a ball.

[0002]

2. Description of the Related Art A general check valve comprises a first chamber and a second chamber.
A seat having an opening formed at a position for partitioning between the chambers, and a valve body disposed at a position detachable from the opening of the seat.

The valve body includes a poppet type one,
There is a ball type. Among these, the poppet type is configured to accommodate a poppet provided with an internal flow path on the inner periphery of a cylindrical guide member, and to allow fluid to flow in and out through the internal flow path of the poppet when the sheet is opened. Is done.
On the other hand, in the ball type, even if the internal flow path is provided in the ball and accommodated in the inner periphery of the cylindrical guide member, the direction of the internal flow path changes depending on the rolling direction of the ball, and the inflow and outflow of the fluid are changed. Since it cannot be performed accurately, a different structure is adopted. Specifically, as illustrated in FIG. 5, the ball a is press-fitted and fixed to the tip of a rod-shaped ball retainer b, and the ball retainer b is guided by a guide member c in a mounting / removing direction with respect to the sheet d. It is usual that the fluid passage when detached from the seat d is configured to be secured on the outer periphery of the ball a or the ball retainer b.

[0004]

However, with such a structure, it takes time and effort to press the ball a into the tip of the ball retainer b, and the use of the guide member c is indispensable. There is a problem that there is no room to reduce the number of points and the number of manufacturing steps.

An object of the present invention is to provide a check valve which effectively solves such a problem.

[0006]

In order to achieve the above object, the present invention employs the following configuration.

That is, the check valve according to the present invention is interposed between the first chamber and the second chamber, and allows the fluid to flow from the first chamber to the second chamber. A sheet having an opening disposed at a position separating the first chamber and the second chamber, wherein the sheet has an opening disposed at a position separating the first chamber and the second chamber. A ball disposed at a position that can be attached to and detached from the seat, and a fluid flow hole disposed at a position offset from the center of the bottom, the ball being disposed movably within the seat with the opening end thereof facing the seat. And a ball retainer.

[0008]

In the check valve of the present invention, the first chamber is the second chamber.
When the pressure is higher than that of the chamber, the ball separates from the seat and moves to the bottom side of the ball retainer. At this time,
Since the fluid flow hole is opened at a position deviated from the center of the bottom, the fluid flowing from the first chamber through the opening of the sheet flows out to the second chamber through the fluid flow hole. . Conversely, when the pressure in the second chamber is higher than that in the first chamber, the ball sits on the seat and closes the opening.
Therefore, the flow of the fluid from the second chamber to the first chamber is prohibited.

[0009] As described above, this device can properly function as a check valve. According to such a configuration, since the ball itself does not need to be fixed and the mounting / removing operation of the ball with respect to the sheet is guided by the ball retainer itself, the ball retainer is guided unless it is necessary to press the ball into the ball retainer. Therefore, it is not necessary to use a special guide member.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 shows an example in which the check valve 2 of the present embodiment is applied to a flow divider. This flow divider opens an inlet port P into which a high pressure is introduced, an outlet port PF to which a load or the like is connected, and a tank port T which communicates with a low pressure region in a valve body. A sliding hole 1a is provided, and a spool 1 incorporating a check valve 2 according to the present invention is slidably fitted in the spool sliding hole 1a.
Is obtained form the chamber S ₁ and the second chamber S ₂ on the downstream side and the secondary district. The spool 1 is normally offset to the right by a spring 3. That is, the first of this shunt
When high pressure fluid flows from the chamber S ₁ inlet port P,
Second chamber S ₂ and the hole 1b provided in the peripheral wall of the spool 1 as indicated by arrows the fluid in the drawing the check valve 2 is opened
To the outlet port PF through the second chamber S ₂
There when it is first pressure higher than the chamber S ₁ closes the check valve 2 consists of a second chamber S ₂ so as to prohibit the reverse flow of the first to the chamber S _1. That is, it has a function of preventing the pressure of the outlet port PF from decreasing even when the pressure of the inlet port P decreases. Further, when the hydraulic pressure introduced into the first chamber S ₁ is becomes abnormally high, the spool 1
It also has a function of diverting part of the fluid to the tank port T by moving leftward against the spring 3, and this function prevents introduction of an excessively high pressure fluid into the outlet port PT. Is done. Note that such a flow dividing function is generally realized by setting a balanced state of the hydraulic pressure acting on both ends of the spool 1 to a predetermined state.

In this embodiment, in this embodiment, the check valve 2 includes a seat 21, a ball 22, and a ball retainer 23.

The sheet 21 is a partition wall formed at a position where the first chamber S ₁ and the second chamber S ₂ can be defined inside the spool 1 described above. The opening 21a extends through the opening 21a. The through portion 21a communicates with the inlet port P via a hole 1c provided in the peripheral wall of the piston 1. The ball 22 is made of steel, is disposed at a position where it can be attached to and detached from the seat 21, and has an opening 21a of the seat 21 when seated.
Is set to a size that can be closed in a liquid-tight manner. As shown in FIGS. 2 to 4, the ball retainer 23 has a bottom portion 23 a whose diameter is increased in a flange shape, an inner diameter capable of movably accommodating the ball 22, and an outer diameter capable of being fitted on the inner periphery of the spool 1. It has a bottomed cylindrical shape composed of a peripheral wall portion 23b having a diameter, and fluid flow holes 23c are penetrated at four equiangular positions offset from the center of the bottom portion 23a. Then, the ball 22 is provided on the inner periphery of the peripheral wall portion 23b of the ball retainer 23.
Is inserted into the inner periphery of the spool 1 from the opening end side, and the opening end is arranged to face the above-mentioned sheet 21, and the bottom 23 a is formed at the position at the inner periphery of the spool 1. Abut on the bottom 1d
The distal end of the spring 3 whose base end is supported by the inner end surface of the valve body is elastically contacted from behind the end of the spring 3. That is, in this embodiment, the spring 3, which is a means for offsetting the spool 1 to the right-hand position, is also used as a means for fixing the ball retainer 23.

Even with such a check valve 2 having a structure different from the conventional one, the functions required as a check valve can be properly exhibited. That is, when the pressure of the first chamber S ₁ is higher than that of the second chamber S ₂ , the ball 22 can move in the ball retainer 23, and the ball 22 is biased toward the bottom 23 a to open the seat 21. The part 21a is opened. At this time, even if the ball 22 is completely in contact with the bottom portion 23a, the fluid flow hole 23c is opened at a position deviated from the center of the bottom portion 23a, so that the first chamber is opened via the opening portion 21a of the seat 21. fluid flowing from S ₁ may flow out the second to the chamber S ₂ without problem through such fluid flow hole 23c. Conversely, when the than the first chamber S ₁ is towards the second chamber S ₂ becomes relatively high pressure, and biased to the open end side ball 22 in the retainer 23, seated in the seat 21 in this position Then, the opening 21a is closed. Therefore, the flow of fluid is reliably inhibited from the second chamber S ₂ to the first chamber S _1. In particular, since the ball 22 is loosely fitted to the ball retainer 23 with a certain amount of play, the ball 22
The operation of sitting on the seat 21 is smoothly performed without difficulty.

The check valve 2 having such a structure is used.
The ball retainer 23 itself allows the ball 22 to move freely and guides the mounting / removal operation of the ball 22 with respect to the seat 21. Therefore, it is unnecessary to press the ball into the ball retainer as in the related art. There is no need to guide the ball retainer at all. This eliminates the need for cumbersome and inefficient ball press-fitting work, and at the same time eliminates the need for a guide member for the ball retainer, which was a conventional essential part, thereby reducing the number of parts.
As a result, it is possible to reduce the cost and size of the entire check valve.

The specific configuration of each part, particularly the cross-sectional shape of the ball retainer, is not limited to the illustrated embodiment, but can be variously modified without departing from the spirit of the present invention.

[0017]

As described above, according to the check valve of the present invention, the ball retainer is formed in a cylindrical shape with a bottom, and the ball is provided on the inner periphery of the ball retainer in a range which does not hinder the operation of attaching and detaching the ball to the seat. It is housed movably and a sufficient flow passage cross-sectional area when the valve is opened is secured by the fluid flow hole. For this reason, the press-fitting structure of the ball into the ball retainer and the guide member for guiding the ball retainer, which are indispensable in the conventional check valve, are unnecessary, and the check valve is practically used as a compact, simple, and easily manufactured check valve. be able to.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a flow divider incorporating a check valve according to an embodiment of the present invention.

FIG. 2 is a perspective view showing the check valve according to the embodiment with a part cut away.

FIG. 3 is a front sectional view of the check valve.

FIG. 4 is a plan view of the check valve.

FIG. 5 is a cross-sectional view of a device incorporating a conventional check valve.

[Explanation of symbols]

S ₁ ... first chamber S ₂ ... second chamber 2 ... check valve 21 ... seat 21a ... opening 22 ... ball 23 ... ball retainer 23a ... bottom 23c ... fluid flow hole

Claims (1)

(57) [Claims] An intervening fluid is provided between a first chamber and a second chamber to permit fluid to flow from the first chamber to the second chamber, and to allow fluid to flow in the opposite direction. A valve having an opening disposed at a position separating the first chamber and the second chamber, and a check valve disposed at a position detachable from the opening of the seat. And a ball retainer which is disposed on the seat with the opening end thereof facing, accommodates the ball movably therein, and has a fluid circulation hole opened at a position offset from the center of the bottom. Check valve characterized by the following.