JPH0674855B2 - Combined relief and stop valve - Google Patents

Description

Detailed Description of the Invention a. Object of the Invention (Industrial field of application) The present invention is a relief-stop composite valve used in a fluid pressure circuit. Specifically, when the spring is held down by the adjusting screw, the valve body closes below the set pressure and acts as a relief valve that opens above the set pressure.When the spring case is pulled up, the valve body is forcibly opened and the pressure The present invention relates to a composite valve that acts as a stop valve that connects a system and a drain.

(Prior Art) Conventionally, a cylindrical mandrel to which a closing member is fixed, which is arranged to come into contact with an annular valve seat and close the valve boat surrounded by the valve seat, and to be screwed to the mandrel. A cylindrical sleeve, the sleeve and the closure member being guided to slide longitudinally within the valve housing in a direction toward and away from the valve seat to bring the closure member into contact with the valve seat. Including a spring arranged to propel the sleeve longitudinally such that rotation of the sleeve with respect to the mandrel changes the axial position of the sleeve with respect to the mandrel and therefore changes the spring pressure which propels the closure member toward the valve seat. A relief valve that is effective for is known from Japanese Utility Model Publication No. 45-27990.
This has a feature that the mandrel can be rotated by a grip to adjust the pressure of the spring from outside the housing.

(Problems to be solved by the invention) However, in the above-mentioned relief valve, a mandrel with a grip is inserted into a sleeve guided in a housing so as to slide in a longitudinal direction, and a screw at a lower portion thereof is screwed into the sleeve. It was made
Since there is no screwing relationship between the screw of the mandrel and the housing, no matter how many times the mandrel is turned by gripping, the sleeve and the annular washer are pulled up to compress the spring, and only the closing force applied to the closing member is increased. Cannot be separated from the valve seat to connect the pressure system with the drain to perform the function of a stop valve that enables maintenance.

The present invention has been made in view of this situation, and accommodates a spring case supporting a valve body, a compressed spring, and a spring retainer in a valve casing, and an adjusting screw screwed to the valve casing for the spring retainer. When the spring is suppressed by this adjusting screw by connecting the valve, the valve body is closed below the set pressure,
When the set pressure is exceeded, it acts as a relief valve, and when the adjustment screw raises the spring case, the valve element moves away from the valve seat and acts as a stop valve that connects the pressure system and the drain. The challenge is to provide.

B. Configuration of the Invention (Means for Solving the Problems) A relief-stop composite valve according to the present invention accommodates a spring case in a valve housing having a valve seat at one end, and is vertically movable, and the valve is provided at one end thereof. A valve body facing the seat is supported, and a spring retainer is supported on the other end, and a spring for pressing the valve body against the valve seat is compression-loaded between the two, and the end opposite to the valve seat of the valve casing is installed. A problem is solved by screwing an adjusting screw onto the spring and connecting the tip of the adjusting screw to the spring retainer, and adjusting the closing force of the valve body by this adjusting screw and forcibly opening the valve. Is.

(Operation) The relief stop combined valve configured as described above,
When the adjustment screw is turned in the forward direction by the handle, the adjustment screw suppresses the spring restraint and pressurizes the spring, and the spring presses the valve body against the valve seat, so that the pressure contact force affects the set pressure of the circuit that acts on the valve body. When balanced, stop the adjustment screw and stop with the stop nut and lock nut, and the valve body will be closed if the circuit pressure is below the set pressure.

However, when the circuit pressure rises abnormally due to the action of back pressure of the actuator connected to the circuit as shown in FIG. The pressure port and the drain port to communicate with each other to discharge a part of the pressure fluid and perform a safety action to prevent the pressure in the circuit from rising, and if the circuit pressure drops to the set value accordingly. The return of the spring causes the valve element to come into contact with the valve seat and close the valve, thus acting as a relief valve for maintaining the set pressure of the circuit.

Also, when maintaining the circuit, turn the screw in the direction to retract it by the handle, and the screw will pull the spring retainer,
When this engages with the spring case, the spring case is pulled up, so the valve element supported at the bottom of the spring case is separated from the valve seat, and the pressure port and the drain port communicate with each other to drain the drain in the circuit or It is now possible to perform maintenance such as allowing fluid to flow into the pipeline from the drain port through the pressure port, and when maintenance is complete, advance the adjusting screw until the stop nut hits the lid body, and the valve body will spring It is elastically pressed against the seat to close at the original set pressure, and acts as a relief valve for holding the circuit pressure.

The above-described operation is performed in the same manner in the compound valve for the accumulator circuit shown in FIG. 2, and the description thereof will be omitted.

(Example) Below, the Example of the relief stop combined valve which concerns on this invention is described.

FIG. 1 shows an embodiment of a composite valve suitable for a main circuit C ₁ partitioned from an actuator A side by an opening / closing valve V ₁ as shown in the conduit diagram of FIG. The valve chamber 2 is provided in the center from above, and the upper end of the valve chamber 2 is closed by the lid 3. The pressure port 4 is opened at the center of the bottom of the valve chamber 2 and the valve seat 5 is provided at the inner end.
And a drain port 6 is opened on the side surface of the deformed portion.

Reference numeral 7 is a spring case that is housed in the valve chamber 2 so as to be able to move up and down. One end of the spring case supports a valve body 8 that comes in contact with and separates from the valve seat 5 described above, and a collar 9 provided in the middle thereof. To the bottom of the spring case 7, and a spring retainer 11 is supported on the other end, that is, on the upper side in the figure, and a spring 10 is compression-loaded between the spring retainer 11 and the collar 9. A joint shaft 12 is continuously provided above the spring retainer 11.

Reference numeral 13 is an adjusting screw screwed into the lid body 3 described above. A handle 14 is attached to the upper end, a rotary joint 15 is provided at the lower end, and the adjusting shaft 13 is connected to the upper end of the joint shaft 12 to move the screw 13 in the forward direction. When turned, the valve body 8 is pressed against the valve seat 5 by the spring 10 and closes at a set pressure or less, and when abnormal pressure occurs, it acts as a relief valve that opens, and the screw 13 is turned in the retreating direction. Then, the spring case 7 is pulled up by the spring retainer 11, the valve body 8 is separated from the valve seat 5 and opened, and the pressure port 4 and the drain port 6 are communicated with each other to discharge the drain from the pressure system. It acts as a stop valve that allows the reverse flow of fluid into the pressure system.

Reference numerals 16 and 17 denote a stop nut and a lock nut screwed to the screw 13 described above. When the spring 10 pressurized by the screw 13 gives a force to the valve body 8 in equilibrium with the set pressure of the fluid, the stop nut 16 is The screw 13 is prevented from moving further against the lid body 3, and the lock nut 17 fixes the stop nut 17 so as not to move.

The composite valve shown in the above-mentioned example was able to reliably perform the action as shown in the above-mentioned action column.

FIG. 2 shows the on-off valve V ₂ as shown in the fluid pressure circuit diagram of FIG.
An example of a composite valve suitable for the circuit C ₂ of the accumulator B partitioned by is shown. The configuration is the same as that of the example of FIG. 1 described above, but in the example of FIG. 1 is different in that the pressure port 4 and the drain port 6 which are provided in opposite directions to each other are provided on the same side so as to be vertically aligned. This embodiment also performs the same operation as that of the above-mentioned embodiment. It is a thing.

C. As described above, the relief stop combined valve of the present invention is a relief valve in which when the spring is compressed by the operation of the adjusting screw, the valve body is pressed against the valve seat and closed below the set pressure, and opens above the set pressure. However, when the spring case is pulled up by the adjusting screw, the valve element separates from the valve seat and communicates the pressure system with the drain, thus acting as a stop valve that enables maintenance, and thus two conventional valves are required. Only one valve is needed, and the equipment and installation costs can be significantly reduced.

The valve body is elastically pressed against the valve seat by the spring, and an excessive tightening force cannot be applied unlike a screw-fastened stop valve, so that the valve body and the valve seat are not damaged.

Since the valve body, the compressed spring, and the spring case containing the spring retainer are only housed in the valve housing, the valve can be formed into a price, size, and shape that are almost the same as those of a normal relief valve.

It has unique effects such as.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view showing an embodiment suitable for a main circuit of a relief / stop combined valve according to the present invention. FIG. 2 is a vertical sectional front view showing an embodiment suitable for the accumulator circuit of the above. FIG. 3 is a circuit diagram of a fluid pressure circuit using the same composite valve. 1 …… Valve element 5 …… Valve seat 7 …… Spring case 10 …… Spring 11 …… Spring retainer 13 …… Adjustment screw

Claims (1)

[Claims] 1. A valve housing having a valve seat at one end, and a vertically movable spring case is housed therein, one end of which supports a valve body facing the valve seat, and the other end of which supports a spring retainer. Then, a spring for pressing the valve body against the valve seat is compression-loaded between the two,
An adjusting screw is screwed onto the end of the valve casing opposite to the valve seat, and the tip of the adjusting screw is connected to the spring retainer. The adjusting screw adjusts the closing force of the valve element and forcibly opens the valve. Relief stop combined valve characterized by that.