JPH0115963Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention introduces fluid into the pilot chamber and draws fluid out from the pilot chamber by switching the pilot switching valve. The present invention relates to a fluid control valve that is provided with a main valve so as to communicate and cut off communication between the fluid control valve and the main valve.

[Conventional technology]

Conventionally, in this type of fluid control valve, fluid is introduced into the pilot chamber formed at the back of the main valve by switching the pilot switching valve, and the main valve slides through the sliding hole by the acting force based on the pressure of the introduced fluid. The main valve separates from the valve seat due to the action force based on the fluid pressure in the inflow path, and the main valve separates from the inflow path and outflow by sitting on the valve seat and blocking the inflow and outflow paths, and drawing out the fluid in the pilot chamber. The passages are communicated with each other so that fluid from the inflow passage is led out to the outflow passage.

[Problem that the invention attempts to solve]

However, when the inflow path is connected to a fluid pressure source and the outflow path is connected to a fluid actuator, the main valve separates from the valve seat due to operation of the pilot switching valve and the fluid actuator is overloaded when the inflow path and outflow path are connected. If the fluid pressure in the outflow path becomes higher than the fluid pressure in the inflow path due to Therefore, a check valve is specially installed in the outflow passage, and this check valve is a large one that can control a large flow rate almost equivalent to that of the main valve, and the problem is that the overall valve structure is complicated and large. The point was hot.

The present invention solves these problems and provides a fluid control valve that is highly safe, compact, and can be manufactured at low cost without the need for a special check valve.

[Means for solving problems]

Therefore, the present invention consists of a small diameter part communicating with the inflow passage and a large diameter part communicating with the outflow passage, and a sliding hole in which a valve seat is formed in the stepped part of the connection, and a sliding hole in which a valve seat is formed in the stepped part. A main valve that is slidably inserted into a sliding hole so as to shut off communication between an inflow passage and an outflow passage by seating on or leaving the valve seat, and a pilot formed on the back of the main valve. It is equipped with a pilot switching valve that operates the main valve by introducing fluid into the pilot chamber or drawing out fluid from the pilot chamber, and the main valve is a piston member that is slidably inserted into the large diameter part of the sliding hole. and a valve member formed so that it can be slidably inserted into the piston member without sliding into the sliding hole and can be seated on the valve seat or removed from the valve seat, and the valve member is formed so that it can be seated on the valve seat or removed from the valve seat. By fitting a valve member into the piston member so as to prevent fluid flow, a fluid chamber defined as a partition is provided in communication with the outflow passage.

[Effect]

In this configuration of the present invention, the fluid in the pilot chamber at the back of the main valve is led out by the switching operation of the pilot switching valve, and when the main valve is disengaged from the valve seat and the inflow path and outflow path communicate with each other, the fluid pressure in the outflow path is increased. When the fluid pressure rises higher than the fluid pressure in the inflow channel, the fluid pressure in the fluid chamber communicating with the outflow channel rises, and the acting force based on the increased fluid pressure causes the valve member to slide relative to the piston member to open the fitting hole. It operates until the person is seated, cutting off the outflow path and inflow path. Therefore, a check valve action that prevents fluid flow from the outflow path to the inflow path can be obtained by the main valve, and a highly safe fluid control valve can be manufactured in a small size and at low cost.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

Reference numeral 1 designates the valve body of the fluid control valve, which includes an inlet P that is connected to a fluid pressure source to allow fluid to flow in, an outlet R that allows fluid to flow out, a pair of load ports A and B that are connected to a fluid actuator C, and a fluid outlet. It has an outlet DR, and four fluid control valves 2, 3, 4, 5 (hereinafter referred to as
(referred to as a valve). 2 shows a valve of the present invention, in which the main valve 43 is configured to cut off communication between the inlet passage 9 communicating with the inlet port P and the outlet passage 10 communicating with the load port A.
is slidably inserted into the sliding hole 6. Sliding hole 6
is composed of a small diameter part communicating with the inflow passage 9 and a large diameter part communicating with the outflow passage 10 via the annular groove 7,
A valve seat 37 is formed in the continuous stepped portion. The main valve 43 includes a piston member 12 that is slidably inserted into the large diameter portion of the sliding hole 6 and has a recessed surface facing the valve seat 37 to form a bottomed insertion hole 45; The valve member 13 is formed into a poppet shape so that it can be slidably inserted into the insertion hole 45 of the piston member 12 without sliding and can be seated on the valve seat 37 and detached from the valve seat 37. There is. Reference numeral 8 denotes a pilot chamber formed at the back of the main valve 43, in which fluid from the pilot passage 34 branched from the inlet passage 9 is introduced by switching the pilot switching valve 36 communicating via the pilot passage 11, and the pressure of the introduced fluid is adjusted. Based on the acting force and spring 1
The main valve 43 is seated on the valve seat 37 by the force 5,
The introduced fluid is discharged from the pilot passage 11 to the discharge passage 35.
By flowing and leading out to the discharge port DR, the main valve 43 is separated from the valve seat 37 against the force of the spring 15 due to the acting force based on the fluid pressure in the inflow path 9. 14 connects the valve member 13 to the piston member 12
By fitting into the fitting hole 45 of the valve member 13, the fluid chamber is partitioned and communicated with the outflow path 10 through the communication path 46 provided in the valve member 13, and the acting force based on the fluid pressure introduced from the outflow path 10 is applied to the valve member. 13 in the direction of seating on the valve seat 37. The valve 3 is constructed by slidably inserting the poppet valve 22 into the sliding hole 16, and by switching the pilot switching valve 36 to the pilot chamber 18 formed at the back of the poppet valve 22.
When the fluid is introduced, the poppet valve 22 is seated on the valve seat 38 due to the acting force based on the pressure of the introduced fluid and the force of the spring 23, and the inflow passage 19 communicating with the supply port P and the load port B are connected. In addition, by switching the pilot switching valve 36, the fluid in the pilot chamber 18 is shut off from the pilot passage 21.
By flowing through and leading to the outlet DR, the inflow path 1
Poppet valve 2 due to the acting force based on the fluid pressure of 9
2 separates from the valve seat 38 against the force of the spring 23, thereby establishing communication between the inlet passage 19 and the outlet passage 20. When the valve 4 is switched, the poppet valve 27 is seated on the valve seat 39 due to the acting force based on the pressure of the fluid flowing through the pilot passage 26 and introduced into the pilot chamber 41 and the force of the spring 28. The inlet passage 24 communicating with the outlet R and the outlet passage 25 communicating with the outlet R are cut off, and the pilot chamber 4
By drawing out the first fluid, the poppet valve 27 is separated from the valve seat 39, and the inflow passage 24 and the outflow passage 25 are communicated with each other. The valve 5 is operated by the switching operation of the pilot switching valve 36, and the poppet valve 32 is seated on the valve seat 40 due to the acting force based on the pressure of the fluid flowing through the pilot passage 31 and introduced into the pilot chamber 42 and the force of the spring 33, and the poppet valve 32 is seated on the valve seat 40, and the poppet valve 32 is opened to the load port B. Inflow channel 29 communicating with
The poppet valve 32 is separated from the valve seat 40 by blocking the outflow path 30 communicating with the outflow port R, and by drawing out the fluid from the pilot chamber 42, the poppet valve 32 is separated from the valve seat 40 and the inflow path 3 is opened.
It is designed to communicate between 0 and 0.

Next, the operation will be explained. In the neutral position of the pilot switching valve 36 in the illustrated state, the four valves 2, 3, 4,
Fluid is introduced into the pilot chambers 8, 18, 41, and 42 of the main valve 43, the poppet valve 22, and
27, 32 are pilot compartments 8, 18, 41, 42
The acting force based on the fluid pressure of the springs 15, 23, 2
8, 33 force and valve seats 37, 38, 39, 40
The fluid actuator C is stopped by sitting on the seat, blocking the inflow passages 9, 19, 24, 29 and the outflow passages 10, 20, 25, 30. From this, when the pilot switching valve 36 is operated to the right position, valves 2 and 5
Only the pilot chambers 8 and 42 are communicated with the discharge port DR via the discharge path 35, and the fluid flowing from the fluid generation source into the inflow port P is transferred from the inflow path 9 to the piston constituting the main valve 43 by an acting force based on pressure. Part 1
2. Both the valve members 13 are slid against the force of the spring 15, and the fluid is led out to the outflow path 10, flows through the load port A, and flows into the fluid actuator C. The fluid actuator C moves upward and flows out from the fluid actuator C. The fluid flows through the load port B and the inflow path 29, acts on the poppet valve 32, causes the poppet valve 32 to slide against the force of the spring 33, and is led out to the outflow path 30 and flows through the outflow port R.
is discharged to the low pressure section. Then, by returning the pilot switching valve 36 to the neutral position, fluid is also introduced into the pilot chambers 8, 42 of the valves 2, 5, and the main valve 43 and poppet valve 32 are moved to the valve seats 37, 40.
The fluid actuator C is seated in the upper position and blocks the inflow passages 9, 29 and the outflow passages 10, 30, and the fluid actuator C stops at the raised position. From this, when the pilot switching valve 36 is switched to the left position, the pilot chamber 1 of the valves 3 and 4 is opened.
8 and 41 are communicated with the discharge port DR via the discharge path 35, and the fluid in the inlet P is led out from the inflow path 19 by sliding the poppet valve body 22 to the outflow path 20, and flows through the load port B to the fluid actuator. flows into C,
The fluid actuator C operates downward, and the fluid flowing out from the fluid actuator C flows through the load port A and the inflow path 24, slides the poppet valve 27, and then flows into the outflow path 2.
5 and is discharged from the outlet R to the low pressure section.
Then, the fluid actuator C descends to the lowered position shown in the figure and returns the pilot switching valve 36 to the neutral position, thereby opening the poppet valves 22, 27.
are seated on the valve seats 38 and 39, and the fluid actuator C stops in the state shown.

With this operation, the main valve 43, which is composed of the piston member 12 and the valve member 13 of the valve 2, draws out the fluid in the pilot chamber 8 by switching the pilot switching valve 36, separates it from the valve seat 37, and connects it to the inflow path 9. Outflow channel 1
0, when an overload acts on the fluid actuator C and the fluid pressure in the outflow path 10 rises higher than the fluid pressure in the inflow path 9, the valve member 13 is inserted into the insertion hole 45 of the piston member 12. As a result, the fluid pressure in the fluid chamber 14 that is partitioned and communicates with the outflow path 10 through the communication passage 46 increases, and the valve member 13 is moved toward the piston member 1 by the acting force based on the increased fluid pressure.
2 and operates until the fitting hole 45 is seated on the valve seat 37 to shut off the outflow path 10 and inflow path 9. Therefore, the main valve 43 prevents fluid flow from the outflow path 10 to the inflow path 9. A fluid control valve with high safety can be manufactured in a small size and at low cost.

[Effect of idea]

As described above, the present invention has a sliding hole configured by connecting a small diameter part communicating with the inflow passage and a large diameter part communicating with the outflow passage, and forming a valve seat in the connected step part, and A main valve that is slidably inserted into a sliding hole so as to shut off communication between an inflow passage and an outflow passage by seating on a valve seat formed on the valve seat and separating from the valve seat, and a main valve formed on the back of the main valve. It is equipped with a pilot switching valve that operates the main valve by introducing fluid into the pilot chamber or drawing out fluid from the pilot chamber, and the main valve has a piston that is slidably inserted into the large diameter part of the sliding hole. and a valve member that is formed so that it can be slidably inserted into the piston member without sliding in the sliding hole and can be seated on the valve seat or removed from the valve seat. By inserting a valve member into the piston member so as to prevent fluid from flowing into the piston member, a partitioned fluid chamber is provided in communication with the outflow path, thereby preventing fluid flow from the outflow path to the inflow path. A stop valve action can be obtained by the main valve, and a highly safe fluid control valve can be manufactured in a small size and at low cost.

In addition, the main valve can be operated by inserting a valve member that is configured to be able to sit on or detach from a valve seat into a piston member that is slidably inserted into a sliding hole without sliding on the sliding hole. Because of the structure, the valve member is formed so that it can be slidably inserted into the sliding hole and seated on the valve seat, and can be detached from the valve seat.The valve member is fitted into the piston member that is slidably inserted into the sliding hole. Although the problems of the present invention can be solved by inserting the main valve into the main valve, the sliding parts of the main valve that must be manufactured with high precision can be reduced compared to this method, making it easier to manufacture. have an effect.

[Brief explanation of the drawing]

The drawing shows an embodiment of the fluid control valve of the present invention,
It is a diagram in which circuit symbols are added to a partial longitudinal section. 6...Sliding hole, 8...Pilot chamber, 9...Inflow path, 10...Outflow path, 12...Piston member,
13... Valve member, 14... Fluid chamber, 36... Pilot switching valve, 37... Valve seat, 43... Main valve.

Claims (1)

[Scope of utility model registration request] It consists of a small diameter part that communicates with the inflow passage and a large diameter part that communicates with the outflow passage, and has a sliding hole with a valve seat formed in the connected stepped part, and a valve seat that is seated in the sliding hole. A main valve that is slidably inserted into a sliding hole so as to cut off communication between an inflow path and an outflow path by separating from the valve seat and introducing fluid into a pilot chamber formed on the back of the main valve. It is equipped with a pilot switching valve that operates the main valve by drawing out the fluid in the pilot chamber, and the main valve has a piston member that is slidably inserted into the large diameter part of the sliding hole, and a piston member that is slidably inserted into the large diameter part of the sliding hole. It consists of a valve member that can be slidably inserted into the piston member without movement and can be seated on or removed from the valve seat, making it possible to prevent fluid flow from the outflow path to the inflow path. A fluid control valve in which a fluid chamber defined by a partition is communicated with an outflow path by fitting a valve member into a piston member.