JPH03603Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an improvement of an in-line type fluid flow rate regulating valve with pressure compensation.

(Prior Art) In-line type pressure-compensated flow rate regulating valves have been developed in order to make the shape compact, space-saving, lightweight, and inexpensive. A device as shown in FIG. 1 is known. This structure has a pressure compensation element 1 and a flow rate adjustment element 2 built into a check valve 3, and is a flow rate adjustment valve with pressure compensation aimed at downsizing and reducing pressure loss during free flow. . This device is extremely compact and small, but the processing of the check valve 3 with a step, the pressure compensation element 1 and the flow rate adjustment element 2 built therein, and the degree of circularity and fitting between these elements The problem was that the process required many man-hours.

A similar in-line type flow rate regulating valve with pressure compensation is, for example, as shown in Japanese Patent Publication No. 59-9795, in which a pressure compensating element and a flow rate compensating element are housed in-line facing each other in the valve body, and the pressure The compensation element has a small diameter part and a large diameter part connected to each other on the outer periphery, and a step part is formed as a pressure acting surface, and an axial through hole is provided inside for fluid to pass through, so that the flow rate can be adjusted to the pressure compensation spool, which is the pressure compensation element. Some valves have been designed to reduce the size of the valve by reducing the area of the pressure-receiving surface on which fluid pressure acts before and after the throttle valve, which is a compensating element, to reduce the generated axial acting force. However, since the area of the pressure-receiving surface of the pressure-compensating spool has been reduced, the pressure compensation accuracy for the set flow rate is poor, and especially when a large flow rate is flowing, the pressure loss due to the restriction is large, resulting in uneven pressure distribution within the pressure-compensating spool. As a result, the fluid force acts on the front and rear cross sections of the pressure compensation spool and the inner step surface, and the large pressure loss due to the large flow rate makes the movement of the pressure compensation spool unstable, making stable pressure compensation impossible. The outflow flow rate from the flow rate adjustment valve became variable. Furthermore, the pressure compensating spool has a small diameter part and a large diameter part on the outer periphery, and the outer periphery of the flow rate compensating element also has a larger diameter part than the small diameter part, so there are three sliding holes and three different diameter parts. It became necessary to process the outer periphery of the sliding contact of the diameter, which increased the number of processing steps and deteriorated accuracy, further deteriorating performance.

(Problem to be solved by the present invention) The problem to be solved by the present invention is to solve the above-mentioned drawbacks of conventional products by increasing the pressure-receiving area of the pressure compensating element.
It has sufficient responsiveness even for large controlled flow rates,
We provide a flow regulating valve with pressure compensation that provides stable and highly accurate pressure compensation, does not cause fluctuations in the flow rate outflow from the flow regulating valve, does not require machining man-hours, and allows for simple and highly accurate machining. It's about doing.

(Means for Solving the Problems) For this reason, the present invention has a pressure compensating element and a flow rate regulating element that are housed in a sliding contact hole of the same diameter formed in a housing so as to face each other in sliding contact with each other in a substantially straight line. The pressure compensation section of the pressure compensation element and the flow rate adjustment section of the flow rate adjustment element are communicated through hollow blind holes provided in each of the elements, and back pressure is formed on the side opposite to the hollow blind hole of the pressure compensation element. This is a flow regulating valve with pressure compensation, characterized in that the area of the pressure receiving surface that receives the pressure of the chamber is the same as the cross-sectional area of the sliding hole.

(Function and Effect) According to this configuration, it is only necessary to make one sliding contact hole of the same diameter, and both elements need be machined to have the same outer diameter, which reduces machining that requires precision and can be done efficiently. This eliminates the need for machining man-hours, and the sliding contact holes of the same diameter and the outer periphery of each element can be machined with a high degree of precision, making it easier to machine, allowing extremely high precision pressure compensation and flow rate adjustment. Now I can do it. In addition, the pressure-receiving surface of the pressure compensating element has the same area as the cross-section of the sliding hole, instead of a stepped part like in conventional products, so it has sufficient responsiveness even for large control flow rates and stable accuracy. High pressure compensation was obtained, and there was no longer any variation in the flow rate outflow from the flow rate adjustment valve.

(Description of Embodiments) An embodiment of the present invention will be described with reference to the drawings. FIG. 2 is a cross-sectional view showing an embodiment of the present invention.
The housing consists of a main body housing 15 and a lid housing 17, and a sliding hole 30 of the same diameter is bored in the axial direction. A pressure compensating element 12 and a flow rate adjusting element 11 are accommodated in the sliding contact hole 30 so as to face each other and to be in sliding contact with each other in a substantially straight line. Furthermore, the pressure compensating section 19 and the flow rate regulating section 24 are communicated through hollow blind holes 31 and 32 provided in the pressure compensating element 12 and the flow rate regulating element 11, respectively. The pressure compensating element 12 includes a piston 13 that is slidably fitted into the sliding contact hole 30 and has a hollow blind hole 31, a spring 16, a back pressure chamber 18, and a pilot line 33 led from the inlet port 23 to the back pressure chamber 18. , and a pressure compensator 1 consisting of a port hole edge 21 of an outlet port 22 and a small hole 20 overlapping with it.
9. The small hole 20 allows the outer peripheral surface of the piston 13 facing the outlet port 22 and the hollow hole 31 to communicate with each other. The other flow rate adjusting element 11 includes a sleeve 14 that is fitted and fixed in the sliding hole 30 and has a hollow through hole, and a rod member 27 that is fitted in the hollow with a screw 28 so as to be slidable in the axial direction. include. The hollow hole becomes a hollow blind hole 32 by the rod member.
Furthermore, the flow compensation element 11 includes a flow adjustment portion 24 consisting of a rod member 27, an outer peripheral edge 26, and a small hole 25. The small hole 25 allows the outer peripheral surface of the sleeve 14 facing the inlet port 23 to communicate with the hollow blind hole 32 .

In operation, pressurized oil enters through inlet port 23 and passes through pilot line 33 to backpressure chamber 18.
As soon as it enters the (primary pressure chamber), it passes through the small hole 25, that is, it is throttled by the flow rate adjustment part 24, and the hollow blind holes 32, 31
It flows into the secondary pressure chamber 29 containing the air, passes through the small hole 20 of the piston 13, that is, is throttled by the pressure adjustment part 19, and flows out to the outlet port 22. These operations are well known, and the piston 13 has a back pressure chamber 18 which is a primary pressure chamber.
The pressure difference between the pressure P ₁ in the secondary pressure chamber 29 and the pressure P ₂ in the secondary pressure chamber 29 is
It will be clear that the spring 16 provides a pressure compensation effect to achieve the set differential pressure.

As described above, the pressure compensating element 12 and the flow rate adjusting element 11 share the housings 15 and 17, and are accommodated in the sliding contact hole 30 of the same diameter facing each other in sliding contact in a substantially straight line, thereby improving accuracy. Required sliding contact hole 3
It is only necessary to process 0 and 1 elements 11 and 12 on the outer periphery of the same diameter, and the number of processing steps is greatly reduced, resulting in low cost. Furthermore, the hole 30 and the outer peripheral surfaces of the pressure compensation element 12 and the flow rate adjustment element 11, which have the same diameter and can be easily machined together, can now be machined with high precision.
The result is a valve that can perform pressure compensation and flow rate adjustment with extremely high precision. Furthermore, the pressure receiving surface of the pressure compensating element 12 that receives the pressure of the back pressure chamber 18 has the same area as the cross-sectional area of the sliding contact hole 30, so the area of the pressure receiving surface is larger than that of the step part of the conventional product. It has sufficient responsiveness to the controlled flow rate, provides stable and highly accurate pressure compensation, and eliminates fluctuations in the outflow flow rate of the flow rate regulating valve. In FIG. 2, the large diameter portion 6 at the right end of the piston 13 is a spring receiver and does not come into sliding contact with the large diameter hole 5 into which the spring 16 is inserted.

The pilot line 33 to the back pressure chamber 18 is preferably led from a port where the pressure is stable, and the valve shown in FIG. 2 is therefore suitable for use in applications where the pressure at the inlet port 23 is stable. On the other hand, FIG. 3 shows a flow regulating valve with pressure compensation suitable for use in applications where the pressure at the outlet port 22 is stable, in which the pilot line 34 is led from the outlet port 22 to the back pressure chamber 18, and This is the same as in FIG. 2 except that the flow rate adjusting section 24 faces the outlet port 22 and the pressure compensating section 19 faces the inlet port 23, and the explanation thereof will be omitted.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a conventional product, and FIGS. 2 and 3 are cross-sectional views showing different embodiments of the present invention. 11...Flow rate adjustment element, 12...Pressure compensation element, 15, 17...Housing, 18...Back pressure chamber, 19...Pressure compensation section, 22...Outlet port,
23...Inlet port, 24...Flow rate adjustment section, 30
...Sliding contact hole, 31, 32...Hollow blind hole, 33, 3
4...Pilot line.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A pressure compensating element and a flow rate regulating element are opposed and slid in sequence in a substantially straight line in a sliding contact hole of the same diameter drilled into a housing having an inlet port and an outlet port. The pressure compensation part of the pressure compensation element and the flow rate adjustment part of the flow rate adjustment element are communicated with each other through a hollow blind hole provided in each of the elements, and a A flow rate regulating valve with pressure compensation, characterized in that the area of the pressure receiving surface that receives the pressure of the formed back pressure chamber is the same as the cross-sectional area of the sliding contact hole. (2) The pressure compensated flow regulating valve according to claim 1 or 2, wherein the pilot line leading to the pressure compensating element back pressure chamber is led from the inlet port. (3) The pressure compensated flow regulating valve according to claim 1 or 2, wherein the pilot line leading to the pressure compensating element back pressure chamber is led from the outlet port.