JPS62127585A - Three-port valve - Google Patents

Abstract

PURPOSE:To improve the safety in operation, by providing for each valve a monitor device for detecting a pressure differential of fluid in a detection channel having one end opening into a fluid chamber and the other end opening into an end portion of the valve. CONSTITUTION:When a first valve 15 is out of operation to maintain a first supply opening portion 9 open, or to late close the first supply opening portion 9, one end of a detection channel 47 is closed by a valve member 39, and a fluid pressure at an inlet port 2 is transmitted to a monitor M through a first detection channel 35. On the other hand, as soon as a second valve stem 24 of a second valve 16 starts moving, a valve member of a second selector valve device 38 is brought into abutment against a valve seat. As a result, a supply channel 5 is isolated from a second detection channel 36, and a fluid pressure at an exhaust port 4 is detected, and is transmitted to the second detection channel 36. Thus, the monitor M detects abnormality from a pressure differential between the first and second detection channels.

Description

[Detailed description of the invention] The present invention has two valves arranged side by side in one main body, and when the two valves are operated together, the inlet port and the outlet port are communicated with each other, and the discharge port is opened. is blocked and at least 1
The present invention relates to a three-port valve in which an inlet port and an outlet port are cut off when one valve is inactive, and an outlet port and a discharge port are communicated with each other to maintain a discharge state.

Conventionally, when the blood suction valve is not operating normally, it is used as a safety valve to discharge fluid from the actuator and prevent excessive force from being applied to the actuator.For example, as a safety valve in a press operation system, it is used between the actuator and the pressure source. The use of a three-port valve in which two valves are arranged side by side in one connected main body is known, for example, from Japanese Patent Laid-Open No. 56-46170.

■This known 3-port valve has a complicated flow path inside the main body,
There was a problem in that processing the main body required time and money.

Furthermore, the known valve has a problem in that a monitor connected to the valve detects the pressure of the fluid sealed between the supply valve body and the spool valve and operates in a state different from the actual flow path pressure.

The present invention solves the above-mentioned problems by providing a structure between a fluid chamber connected to an outlet port and a supply chamber connected to an inlet port via one supply channel, and a connection between the fluid chamber and a discharge port. Two openings are provided in the middle of the supply flow path, and the two openings and the opening and closing ports are arranged side by side. The two opening/closing ports provided in one supply channel can be opened and closed individually by the two valves, and when at least one of the valves is in the non-operating position, the supply channel is opened and closed. being closed to prevent fluid supply from the inlet port to the fluid chamber; and forming a detection channel in the valve with one end opening into the fluid chamber and the other end opening into an end of the valve; This was achieved by a three-port valve characterized in that it is connected to a monitoring device that detects the difference in fluid pressure in the rain detection channel.

According to the present invention, under normal conditions, both valves are operated simultaneously by the pilot valve, and the two opening/closing ports of one supply flow path are simultaneously opened, thereby communicating between the inlet port and the outlet port.

Pressure fluid is supplied to the actuator from a pressure source. At this time, each part closes the opening between the outlet port and the discharge port.

When both valves are inactive, the two openings provided in the supply flow path and the two openings between the fluid chamber and the supply chamber are both closed, and the fluid is connected to the pressure source. There is no flow from the inlet port to the outlet port. At this time, the opening between the discharge chamber and the fluid chamber is opened, and the pressure fluid of the actuator is discharged through the discharge port.

In the case of an abnormal condition in which one valve does not actually operate even when both valves are operated, the valve that does not operate closes the supply flow path and opens the opening between the discharge chamber and the fluid chamber. So,
Even though the other valve opens the supply channel and opens the opening between the supply chamber and the fluid chamber, no fluid can reach the supply chamber. Therefore, fluid does not flow from the inlet port to the outlet port.

The actuator fluid is discharged from the discharge port because the discharge chamber is opened by the stationary valve. As a result, in an abnormal state, fluid does not flow into the fluid chamber, and unreasonable fluid pressure does not act on the actuator.

If both valves open and close the supply opening at the same time, the pressure transmitted to the monitoring device via the detection path formed in both valves is the same, and it is possible to determine whether one valve is stuck or not. , in the case of an abnormal condition where movement is delayed, whether the supply opening is opened or closed, one side sensitively detects the fluid pressure at the artificial port and the other side sensitively detects the fluid pressure at the discharge port, so it can be monitored. Different pressures act on both sides of the device,
Detects abnormalities by detecting pressure differences.

In the top view, an inlet port 2, an outlet port 3, and a discharge port 4 are formed in the main body 1, and the inlet port 1-2 is connected to the supply chamber 6 via the supply channel 5, and the outlet port 3 is connected to the supply chamber 6 through the supply channel 5. is connected to the fluid chamber 7, and the discharge port 4 is connected to the discharge chamber 8. The supply chamber 6 has a fluid chamber 7, a first supply opening 9 and a second supply opening 9.
The two openings of the supply opening 10 communicate with each other. The discharge chamber 8 communicates with the fluid chamber 7 through two openings, a first discharge opening 11 and a second discharge opening 12. Supply channel 5
is provided with two opening/closing openings, a first opening/closing opening I3 and a second opening/closing opening 14.

Inside the main body 1, two valves, a first valve 15 and a second valve 16, are arranged side by side. The first valve 15 has a first supply opening 9
a first supply valve body 17 seatable in the first supply valve body 17 and a first discharge opening 11;
The first valve stem 20 has a first discharge valve body 18 that can be seated on the valve stem 20 and a first auxiliary valve body 19 that opens and closes the first opening/closing port 13 . The second valve 16 includes a second supply valve body 21 that can be seated in the second supply opening 10 , a second discharge valve body 22 that can be seated in the second discharge opening 12 , and a second valve body 22 that can be seated in the second discharge opening 12 . It consists of a second valve stem 24 having two auxiliary valve bodies 23.

When the first discharge valve body 18 is seated in the first discharge opening 11, the first supply valve body I7 and the first auxiliary valve body 19 are spaced apart from the first supply opening 9 and the first opening/closing port 13, respectively. The first supply valve body 17 and the first auxiliary valve body 9 are respectively opened.
The relative positions of the respective valve bodies are selected such that when seated in the supply opening 9 and the first opening/closing port 13, the first discharge valve body 18 separates from the first discharge opening 11 and opens the opening. .

Similarly, when the second discharge valve body 22 is seated in the second discharge opening 12, the second supply valve body 21 and the second auxiliary valve body 23 are removed from the second supply opening 10 and the second opening/closing port 14, respectively. The second supply valve body 21 and the second auxiliary valve body 23 are separated and open their respective openings.
The relative positions of the respective valve bodies are such that when the valves are seated in the second supply opening 10 and the second opening/closing opening 14, the second discharge valve body 22 moves away from the second discharge opening 12 and opens the opening. Selected.

In the illustrated example, the first supply valve body 17 is designed as a poppet valve for the first supply opening 9, and the first auxiliary valve body 19 is designed as a spool valve. At the same time, the first supply valve body 17 is formed to slide sealingly through the opening of the partition wall 45 between the supply chamber 6 and the supply channel 5.
The portion 7 that passes through the partition wall may be a small diameter portion of the valve stem. The second supply valve body 21 is the second supply opening 10
The second auxiliary valve body 23 is formed as a poppet valve for
is designed as a spool valve. Second auxiliary valve body 23
At the same time, it is formed to slide in a sealing manner through the opening of the partition wall 46 between the supply channel 5 and the chamber 25 following the supply channel 5.

The first valve 15 has a first piston 26 , and the first piston 26 has a first cylinder chamber 27 formed inside the main body 1 .
The second valve 16 has a second piston 28 , which is slidably guided in the body 1 , and the second valve 16 has a second piston 28 formed inside the body 1 .
It is guided by sliding motion into the cylinder chamber 29. First piston 26
has a pressure receiving area larger than the pressure receiving area of the first auxiliary valve body 19, and the second piston is formed so as to have a larger pressure receiving area than the second auxiliary valve body 23.

The main body 1 is provided with two pilot valves 30 and 31, either integrally or separately. The first pilot valve 30 and the second
The inlet port of the pilot valve 31 is connected to the supply channel 5 by a channel 32, and the outlet port of the first pilot valve 30 is connected to the supply channel 5 by a channel 32.
13 into the first cylinder chamber 27, and the outlet port of the second pilot valve 31 into the second cylinder chamber 2 through a flow path 34.
9 is connected.

Two detection paths 35 and 36 are formed in the main body 1 and are connected to a monitoring device (monitor device M shown schematically in FIG. 2), and the first detection path 35 is supplied via a first switching valve device 37. In the flow path 5, the second detection path 36 is connected to the supply flow path 5 via a second switching valve device 38.

The first switching valve device 37 has a valve body 39 that seats on a valve seat of an opening formed in the first detection path 35 and a spring 40 that presses the valve body 39 against the valve seat. is the detection path 36
a valve body 41 seated on a valve seat of an opening formed in the valve body 4;
1 to the valve seat. First detection path 3
5 is a first stem chamber 43 that slides and guides the end of the first valve stem 20 on the side closer to the monitor device than the first switching valve device 37;
The second detection path 36 communicates with a second stem chamber 44 that slides and guides the end of the second valve stem 24 on the side closer to the monitor device than the second switching valve device 38 .

A first stem chamber 43 and a second stem chamber 44 are formed in the main body 1 .

The first valve stem 20 has a detection flow path 4 whose one end is in constant open communication with the fluid chamber 6 near the first supply valve body 17 and whose other end is open to the first stem chamber 43 at the end of the first valve stem.
7 is formed, and the second valve stem 24 has one end in constant open communication with the fluid chamber 6 near the second supply valve body 21 and the other end open in the second stem chamber 44 at the end of the second valve stem. A detection channel 48 is formed.

If this device is simply represented by symbols using JIS symbols, it can be represented as shown in FIG.

The operation of the above three-port valve will be explained.

When the normal pilot valve 30.31 is in the inoperative state, the fluid pressure in the supply channel 5 acting on the first and second auxiliary valve bodies 19.23 causes the first and second valves 15.16 to operate as shown in the figure. It is held in the position shown. In an inoperative pilot valve, the outlet port communicates with the discharge port and the inlet port is blocked.

When the pilot valves 30 and 31 are actuated, the inlet port and the outlet port communicate with each other, fluid is supplied from the supply channel 5 to the first cylinder chamber 27 and the second cylinder chamber 29 via the channel 32, and the first Since the pressure receiving area of the piston 27 is larger than that of the first auxiliary valve body 19, the second piston 27 also has a larger pressure receiving area than the first auxiliary valve body 19.
Since the pressure receiving area of 8 is larger than the pressure receiving area of the second auxiliary valve body 23, the first valve 15 and the second valve 16 are moved downward in the figure, and the first and second supply openings 9.10 and The first and second opening/closing ports 13.14 are opened, and the first and second discharge openings 1
1.12 will be closed. This allows the pressure fluid to flow through the supply channel 5.
to the supply chamber 6 through two further openings and ports 9.10 to the fluid chamber 7 and to the outlet port 3. When the pilot valve 30.31 is deactivated, it is moved to the position shown in the figure by the fluid pressure acting on the first and second auxiliary valve bodies 19.23.

The pilot valves 30, 31 are always actuated at the same time, but if an abnormal condition occurs in which one of the pilot valves or one of the two valves 15, 16 does not operate, the first valve 15 is not actuated. , the first opening/closing port 13 remains closed by the first auxiliary valve body 19, and the supply flow path 5 remains closed by the first auxiliary valve body 1.
Since it is blocked by 9, fluid does not flow into the fluid chamber 6. Therefore, even if the second #-16 is activated, the second supply opening 10 is opened, and the supply chamber 6 and the fluid chamber 7 communicate with each other, no fluid is supplied to the outlet port. The fluid chamber 7 communicates with the discharge chamber 8 by means of a first discharge opening 11, so that the outlet port 3 communicates with the discharge port 4.

When the second valve 16 is inactive, the second opening/closing port 14
? Since the second auxiliary valve body 23 remains closed and the supply flow path 5 is blocked by the second auxiliary valve body 23, fluid does not flow into the fluid chamber 6. Therefore, the first valve 15 operates,
Even when the first supply opening 9 is opened and the supply chamber 6 and the fluid chamber 7 are in communication, no fluid is supplied to the outlet port. The fluid chamber 7 communicates with the discharge chamber 8 by means of the second discharge opening 12, so that the outlet port 3 communicates with the discharge port 4.

When both valves 15,16 are actuated simultaneously, the supply openings are opened or closed simultaneously. in this case,
First and second detection channels 47 formed in both valve stems
．． 48 transmits the same pressure to the monitor via detection paths 35,36. When the supply opening 9 , 10 is closed, the detection channels 47 , 48 open into the fluid chamber 7 and therefore transmit the pressure of the fluid chamber 7 communicating with the discharge port 4 . When the supply opening 9.10 is opened, the end of the valve stem abuts against the valve body 39.41 of the first and second switching valve devices 37.38, removing the valve body 39.41 from the valve seat. Therefore, the detection channel 47.4 is closed and the pressure in the fluid chamber 7 is not transmitted, and the detection channel 35.36 is simultaneously communicated with the supply channel 5, so that the fluid pressure in the inlet port 2 is monitored. communicated. In either case, since the transmitted pressures of both detection paths 35 and 36 are the same, the monitor does not detect any abnormality.

When the first valve I5 is inactive and leaves the first supply opening 9 closed, or when it moves slowly and delays opening the first supply opening 9, a Since the first detection channel 47 opens into a fluid chamber connected to the discharge port, the fluid pressure at the discharge port is detected. Since the first detection channel 47 opens into the first stem chamber 43, the fluid pressure of the discharge port is transmitted to the monitor via the detection channel 35. On the other hand, the second valve 16 is activated, and immediately after opening the second supply opening 10, the end of the second valve stem 24 comes into contact with the valve body 41 of the second switching valve device 38, and the second detection flow path 48 is opened. One end is closed by the valve body 41, and the valve body 41 is separated from the valve seat. The second detection path 36 thus communicates with the supply channel 5 and the fluid pressure in the inlet port 2 is transmitted to the monitor via the second detection path 36 . At this time, since there is a difference between the pressure transmitted by the first detection path 35 and the pressure transmitted by the second detection path 36, the monitor detects and alerts the occurrence of an abnormality.

When the first valve 15 is inactive and leaves the first supply opening 9 open, or when it moves slowly and delays closing the first supply opening 9, the end of the first valve stem 20 contacts the valve element 39 of the first switching valve device 37, one end of the detection flow path 47 is closed by the valve element 39, and the valve element 39 is separated from the valve seat, so the first I★ outlet path 35 is a supply flow. The fluid pressure in the inlet port 2 is maintained in communication with the first sensing path 35 to the monitor. Second valve 16 that operates on one side
Then, as soon as the second valve stem 24 starts to move, it seats the valve body of the second switching valve device 38 on the valve seat and leaves the valve body 41, so that there is no space between the supply flow path 5 and the second detection path 36. is blocked, and the second detection flow path 48 is connected to the discharge port in the vicinity of the second supply opening 10, i.e., the pressure in the fluid chamber 7 connected to the discharge port 4.
The fluid pressure is detected and transmitted to the second detection path 36. At this time, the pressure transmitted by the first detection path 35 and the second detection path 36
This causes a difference in the transmitted pressure, so the monitor detects and alerts you to the occurrence of an abnormality.

The case where the second valve 16 is in the non-operating state is also completely similar to the above, so the explanation will be omitted.

According to the present invention, when one of the two valves does not actuate or is delayed in actuation, the actuating valve is sensitive to the beginning of its movement, whether the actuating valve opens or closes the supply opening. Since it is now possible to react, the problem of poor responsiveness when closing, which was the case in the past, has been resolved.

According to the present invention, a 3-port valve as a double safety valve with a simple structure and reliable operation has been obtained.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a double safety valve according to the invention, and FIG. 2 is a schematic diagram expressed symbolically.

Claims (2)

[Claims] (1) A valve body having a supply chamber connected to an inlet port via one supply flow path, a fluid chamber connected to an outlet port, and a discharge chamber connected to a discharge port, and a valve body provided side by side within the valve body. the supply chamber and the fluid chamber are cut off when at least one of the two valves is inactive; In the three-port valve in which the fluid chamber and the discharge chamber communicate with each other, two supply openings communicate between the fluid chamber and the supply chamber, and between the fluid chamber and the discharge chamber. two discharge openings that communicate with each other, and two opening/closing ports formed in the middle of the supply flow path, the first valve of the two valves opening and closing the first discharge opening. 1 discharge valve body, a first supply valve body that opens and closes the first supply opening, and a first supply valve body that opens and closes the first opening and closing port.
The second valve includes a first valve stem provided with an auxiliary valve body, a second discharge valve body that opens and closes a second discharge opening, a second supply valve body that opens and closes a second supply opening, and a second opening/closing opening. and a second auxiliary valve body that opens and closes, and when the first and second discharge valve bodies are respectively seated in the discharge openings, the first and second supply valve bodies and the first and second supply valve bodies are arranged. The second auxiliary valve bodies each open an opening, and when the first and second supply valve bodies and the first and second auxiliary valve bodies are respectively seated in the openings, the first and second discharge valve bodies open. the first to open the respective discharge openings.
and a second valve stem is formed, and one end of each of the valve stems opens toward the fluid chamber near the valve seat contact surface of the supply valve body, and the other end opens near the end on the opposite side from the discharge valve body. A detection flow path is formed that opens to the detection flow path, and the other ends of the detection flow path are respectively connected to a monitor device that detects a difference in fluid pressure between the two detection flow paths, and both of the two valves are connected to the A three-port valve, characterized in that a pilot valve holds a discharge valve body in a position where an opening is opened when the valve is not operated, and a supply valve body and an auxiliary valve body are held in a position where the opening is closed. (2) the monitoring device is connected to the supply flow path by two detection paths with a switching valve device interposed therebetween, and the switching valve device has a valve body that normally shuts off the detection path by spring pressure;
The other end of the valve stem is arranged as a push rod of the valve body, the other end opening of the detection flow path communicates with the detection path on the monitor device side of the switching valve device, and the other end of the valve stem When activated, the valve element of the switching valve device is pressed to the open position to connect the supply flow path and the monitoring device, and at the same time close the detection flow path opening, and when it is not activated, it moves away from the valve element and connects the supply flow path and the monitoring device. The three-port valve according to claim 1, wherein the three-port valve communicates with the monitoring device and the fluid chamber by blocking the connection between the monitoring device and the fluid chamber and simultaneously opening the detection flow path opening.