JPH0126941Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a switching valve used in a hydraulic circuit or the like.

(Conventional technology) Conventionally, the switching valve used in the hydraulic circuit is
As shown in the figure. In this figure, an outer cylindrical body 1 has a high pressure side port 2 and a low pressure side port 3, and a step surface is formed in the middle of the flow path from the high pressure side port 2 to the low pressure side port 3 inside the outer cylindrical body. A valve seat portion 4 is formed. The valve seat portion 4 divides the inside of the outer cylinder into a high pressure section and a low pressure section. A spring receiver 6 is attached to the end of the outer cylinder 1 on the high pressure side by a pin 5.
is fixed, and a coil spring 8 is disposed between a spherical body 7 serving as a valve body disposed on the valve seat portion 4 and a spring receiver 6. The coil spring 8
A stopper rod 9 for regulating the movement range of the sphere 7 is arranged inside the sphere. On the other hand, in the low pressure part of the outer cylinder body, there is a spool as an operating member for disengaging the sphere 7 from the valve seat part 4 in response to a mechanical operating force F from a rod 11 such as an external electromagnetic solenoid or electromagnetic valve. 10 are slidably fitted.

The switching valve as described above is used by being attached to a structure 15 such as a casing of a hydraulic pump.
Now, if there is no mechanical operating force F, the sphere 7 is pressed against the valve seat 4 by the spring force of the coil spring 8, and the flow path from the high pressure side port 2 to the low pressure side port 3 is blocked. There is. On the other hand, if a mechanical operating force F from an electromagnetic solenoid or the like is applied, the spool 10 moves to the left, causing the sphere 7 to separate from the valve seat portion 4. As a result, the high pressure side port 2 and the low pressure side port 3 communicate with each other.

(Problems to be Solved by the Invention) By the way, in the structure of the conventional switching valve shown in FIG. Due to this separation, oil suddenly flows from the high pressure side to the low pressure side, causing unnecessary vibrations in hydraulic piping and hydraulic equipment such as cylinders, and applying shock to the hydraulic piping, which may eventually cause damage to the hydraulic piping. There was a danger of doing so.

(Means for Solving the Problems) In view of the above points, the present invention makes the detachment movement of the valve body, which is pressed against the valve seat part by a spring force so as to block the flow path, gentle. It is an object of the present invention to provide a switching valve that can prevent the generation of vibration noise when communicating between a high pressure side and a low pressure side, and can alleviate the impact on hydraulic piping.

In the present invention, a high-pressure side port and a low-pressure side port are formed in the outer cylinder, and a valve seat is formed in the middle of the flow path from the high-pressure side port to the low-pressure side port inside the outer cylinder. The inside of the cylindrical body is divided into a high pressure part and a low pressure part, and a valve body is disposed in the valve seat part to be pressed against the flow path by a spring force, and the valve body is pressed against the valve seat by a mechanical operating force. In order to solve the above-mentioned conventional problems in a structure in which an actuation member is detached from the valve seat, a bottomed cylindrical body for a damper is fixed in the high pressure part, and A stopper rod for regulating the movement range of the valve body is slidably fitted therein. The spring force is applied to the valve body via the stopper rod.

(Function) In the configuration of the present invention, when the valve body is in pressure contact with the valve seat, a damper chamber containing fluid is formed inside the bottomed damper cylindrical body into which the stopper rod is fitted. There is. Therefore, when the valve body is removed, the stopper rod acts as a damper by moving while pushing out the fluid in the damper chamber, and the valve body is removed slowly.

(Example) Hereinafter, an example of the switching valve according to the present invention will be described with reference to the drawings.

In FIG. 1, a valve seat part 4 is formed by a stepped surface in the middle of the flow path from the high pressure side port 2 to the low pressure side port 3 inside the outer cylinder body 1, and this valve seat part 4 allows the outer cylinder body to The interior is divided into a high pressure section and a low pressure section. A bottomed cylindrical body 21 for a damper, which also serves as a spring receiver, is fixed to the end of the outer cylindrical body 1 on the high-pressure side side by a C-shaped retaining ring 20. The bottomed cylindrical body 2
A stopper rod 22 for regulating the movement range of the sphere 7 as a valve body is slidably fitted on the inner circumference of the valve body 1.
A coil spring 2 is installed between the ring 23 fitted to the tip of the rod 22 and the rear end of the bottomed cylindrical body 21.
4 is placed. As a result, the rod 22 is urged in the protruding direction by the spring force, and presses the sphere 7 against the valve seat 4. On the other hand, a spool 10 (operating member) is provided in the low-pressure part of the outer cylinder body for detaching the sphere 7 from the valve seat part 4 in response to a mechanical operating force F from a rod 11 such as an external electromagnetic solenoid or electromagnetic valve. ) are slidably fitted.

The switching valve of the above embodiment is used by being attached to a structure 15 such as a casing of a hydraulic pump.
Now, if there is no mechanical operating force F, the stopper rod 22 will protrude due to the spring force of the coil spring 24, and the sphere 7 will be in pressure contact with the valve seat 4, and the low pressure side port 3 will be lower than the high pressure side port 2. The flow path leading to is blocked. At this time, the inside of the damper bottomed cylindrical body 21 is a damper chamber D in which oil is collected.

On the other hand, if a mechanical operating force F from an electromagnetic solenoid or the like is applied, the spool 10 moves to the left, causing the sphere 7 to separate from the valve seat portion 4. At this time, the stopper rod 22 moves backward while pushing out the oil in the damper chamber D, which prevents the ball 7 from moving rapidly and moves the ball 7 slowly (for example, 0.2
It can be set to about 0.3 seconds to about several seconds if necessary. )break away. As a result, oil is relatively gently supplied from the high-pressure side port 2 to the low-pressure side port 3, so that vibration of the hydraulic piping and hydraulic equipment can be prevented, and damage to the hydraulic piping can be prevented.

Note that a minute gap must exist between the inner circumferential surface of the damper bottomed cylindrical body 21 and the outer circumferential surface of the stopper rod 22, but this minute gap is inevitably generated due to processing accuracy. No special processing is required. In addition, if the sphere 7 and the rod 22 are integrally constructed, the movement of the sphere 7 from its detached state to its return to its pressed state against the valve seat portion 4 can be made slow. Furthermore, a conical valve body may be used instead of the integral structure of sphere and rod.

FIG. 2 is an application example showing the application of the switching valve of the present invention. When oil in an oil tank 30 is supplied to a hydraulic cylinder 32 by a hydraulic pump 31, the tank 30
It is used as a return valve to reflux the water. In this way, it is possible to prevent vibration of the cylinder 32 and vibration and damage to the piping when the switching valve 40 is opened.

FIG. 3 shows another application example in which, when oil in an oil tank 30 is supplied to a hydraulic motor 33 by a hydraulic pump 31, the switching valve 40 of the present invention is used to return the oil in the motor 33 to the tank 30. It is used as a return valve. In this way, it is possible to prevent vibration of the motor 33 and vibration and damage to the piping when the switching valve 40 is opened, and in addition, when the oil in the motor is refluxed,
The motor side can be operated manually.

(Effect of the invention) As explained above, according to the switching valve of the invention, a high pressure side port and a low pressure side port are formed in the outer cylinder, and the low pressure side port is lower than the high pressure side port inside the outer cylinder. A valve is formed with a valve seat part in the middle of the flow path toward the outer cylindrical body to divide the inside of the outer cylinder into a high pressure part and a low pressure part, and is pressed against the valve seat part by a spring force so as to block the flow path. In the structure, a bottomed cylindrical body for a damper is fixed in the high pressure part, and a bottomed cylindrical body for a damper is fixed in the high pressure part. A stopper rod that restricts the movement range of the valve body is slidably fitted on the inner periphery of the valve body, and the spring force is applied to the valve body through the stopper rod, so that the valve body does not come off. By slowing down the operation, it is possible to prevent the generation of vibration noise during communication between the high pressure side and the low pressure side, and to reduce the impact on the hydraulic piping. Furthermore, there is no need to make any major structural changes to conventional products, and the product can be manufactured at low cost.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the switching valve according to the present invention, FIG. 2 is a hydraulic circuit diagram showing an application example of the switching valve according to the invention, and FIG. 3 is a hydraulic circuit diagram showing another application example. FIG. 4 is a sectional view showing a conventional switching valve. DESCRIPTION OF SYMBOLS 1... Outer cylinder body, 2... High pressure side port, 3... Low pressure side port, 4... Valve seat part, 7... Sphere, 10...
... Spool, 21 ... Bottomed cylindrical body for damper, 2
2... Rod for stopper, 24... Coil spring, D... Damper chamber.

Claims (1)

[Claims for Utility Model Registration] (1) A high-pressure side port and a low-pressure side port are formed in the outer cylinder, and a valve seat is provided in the middle of the flow path from the high-pressure side port to the low-pressure side port inside the outer cylinder. The inside of the outer cylindrical body is divided into a high pressure part and a low pressure part by forming a section, and a valve body that is pressed against the valve seat part by a spring force so as to block the flow path is arranged, and a mechanical In the switching valve, which is provided with an actuating member that detaches the valve body from the valve seat portion by operating force, a bottomed cylindrical body for a damper is fixed in the high pressure part, and the bottomed cylindrical body is fixed to the inner periphery of the bottomed cylindrical body. A switching valve characterized in that a stopper rod for regulating the movement range of a valve body is slidably fitted, and the spring force is applied to the valve body via the stopper rod. (2) The switching valve according to claim 1, wherein the valve body and the stopper rod have an integral structure.