JPS62127580A - Double safety valve - Google Patents

Abstract

PURPOSE:To improve the responsiveness of detection, by providing a first restriction between an opening of a monitor channel and a fluid chamber, and also providing a second restriction between an outlet port and a supply opening portion. CONSTITUTION:In the event that a first valve stem 14 fails to operate because of any reasons, and a second valve stem 17 is operated, a fluid at an outlet port 3 is discharged through a second restriction 37 and a first discharge opening portion 10 to a discharge chamber 7. A fluid pressure supplied from a supply chamber 5 is reduced mainly at the first restriction 36. Therefore, a monitor channel 34 detects a pressure close to the pressure at an inlet port 2, and a monitor channel 33 detects a pressure close to the pressure at a discharge port 4. Accordingly, a monitor M detects a pressure differential to sense the abnormality.

Description

Detailed Description of the Invention: Back 11 colors The present invention relates to a double safety valve that has two valve stems inside and has a function to detect an abnormality when one valve does not operate or is delayed in operation. It is.

Prior Art As a safety valve that is connected between an actuator and a pressure source and drains the actuator's fluid except when the valve is operating normally to prevent excessive force from being applied to the actuator, it is used, for example, in a press operation. As a safety valve for the system, two sets of valves are arranged side by side in one main body, and the flow rate from the fluid chamber is higher than that of the six valves from the supply chamber connected to the supply port to the fluid chamber connected to the outlet port. The flow rate of the six valves connected to the port is set to a large value, and if one valve does not operate or has a delay in operation, fluid is discharged from the discharge chamber and pressure is applied to the outlet port. It is known to use sealed valves. In this conventional dual-type 3-port valve, a monitor detects the pressure difference near the openings of both valves in the fluid chamber due to the opening and closing of both valves, and recognizes it as an abnormality if a pressure difference occurs. .

Problems with the Prior Art In the prior art described above, when one valve in the main body does not operate or there is a delay in operation, the fluid flowing from the outlet to the discharge port is discharged without passing through the detection port detected by the monitor. Therefore, when the valve closes, the pressure difference between the two valves does not respond sensitively, resulting in a problem of poor responsiveness.

Means for Solving the Problems The present invention solves the above problems by providing a main body with a supply chamber connected to a supply port, a fluid chamber connected to an outlet port, and a discharge chamber connected to a discharge port. The fluid chamber has two
The supply openings communicate with the supply chamber and the two discharge openings communicate with the discharge chamber, and the supply openings and the discharge openings are each formed coaxially with each other, and each One individually pilot-operated valve stem passes through each of the two poppet discs and, when the one poppet disc is seated in the opening, the other poppet valve. The body is formed to open an opening, and a monitor channel is provided that opens toward the fluid chamber from the valve seat of the supply opening, and a first restrictor is provided between the monitor channel opening and the fluid chamber. and the fluid chamber is provided with a second throttle that partitions between the outlet port and the supply opening, and the first throttle has a larger throttle amount than the second throttle. The problem was solved by a double safety valve featuring

Embodiment The structure and operation of the present invention will be explained in detail based on the embodiment shown in the drawings.

In FIG. 1, the main body 1 has a supply port 2, an outlet port 3, and a discharge port 4. A supply chamber 5 is connected to the supply port 2, and a fluid chamber 6 is connected to the outlet port 3. A discharge chamber 7 is connected to the discharge port 4 .

The fluid chamber 6 is connected to the supply chamber 5 by a first supply opening 8 and a second supply opening 9, and to the discharge chamber 7 by a first discharge opening IIO and a second discharge opening 11. 1st supply opening +
18 and the second supply opening 9, the first discharge opening 10 and the second discharge opening 11 have a large opening area. The first supply opening 8 is formed coaxially with the first discharge opening lO, and the second supply opening 9 is formed coaxially with the second discharge opening 11.

First poppet valve body 1 seated on the valve seat of the first supply opening 8
2 and a second poppet valve body I3 seated on the valve seat of the first discharge opening 10 are formed on the first valve stem I4, and a third poppet valve body 15 seated on the valve seat of the second supply opening @9 A fourth poppet valve body 16 is formed on the second valve stem 17 to seat the valve seat of the second discharge opening 11 . No. I poppet valve body 1
2. When the third poppet valve body 15 is seated in the opening,
The second poppet valve body 13 and the fourth poppet valve body 1G open their respective openings, and conversely, when the second poppet valve body 13 and the fourth poppet valve body 16 are seated in the openings, the first poppet valve body 12 and the third poppet valve body +5 each open an opening.

The first valve stem I4 is formed with a first piston 18 having a larger pressure receiving area than the first valve body 12, and a first valve stem guide rod 19 having a smaller pressure receiving area than the first piston 18. The piston 18 is slidingly guided in a first cylinder part 20 of the body 1 and the guide rod I9 of the first valve stem is slidingly guided in a second cylinder part 21 of the body 1. Similarly, the second valve stem 17 has a larger pressure receiving area than the third poppet valve body 15.

Large second piston 22 and second valve stem guide rod 23
and the second piston 22 is slidably guided in the third cylinder part 24 of the main body l, and the second piston 22 is slidably guided in the third cylinder part 24 of the second valve stem.
3 is slidably guided by the fourth cylinder 1 25 of the main body I.

The first cylinder portion 20 is connected to the first cylinder by a pilot passage 26.
A third valve connected to the outlet port of the pilot solenoid valve 27
The cylinder portion 24 is connected by a pilot passage 28 to the outlet boat of a second pilot solenoid valve 29. The artificial port of each pilot solenoid valve 27, 29 is connected to the supply chamber 5 via a channel 30, the second cylinder part 21 via a channel 31, and the fourth cylinder part 25 via a channel 32. It will be communicated to. A first monitor flow path 33 extends 1 m closer to the fluid chamber 6 than the valve seat of the first supply opening 8 , and a second monitor flow path 34 extends 1 m closer to the fluid chamber 6 than the valve seat of the second supply opening 9 . Open your mouth. The first monitor channel 33 and the second monitor channel 34
are each connected to a monitor (not shown).

From the first monitor channel 33 of the first supply opening 8 to the fluid chamber 6
A first throttle 35 is disposed on the side of the fluid chamber 6, for example, near the boundary with the fluid chamber 6, and similarly, a first throttle 35 is disposed on the side of the fluid chamber 6 from the second monitor channel 34 of the second supply opening 9, for example, near the boundary with the fluid chamber 6. A first diaphragm 36 is arranged near the boundary. The fluid chamber 6 is provided with a second restriction 3 delimiting between the outlet 3 and the respective supply opening 8.9.
7 and 38 are formed.

One or more second apertures 37 and 38 may be formed.

The first aperture 35 and the second aperture 37 may be integrated, or the first aperture 35 and the second aperture 37 may be integrated.
The aperture 36 and the second aperture 38 may be integrated to form a ring body 39 as shown in FIG. 2, and the ring body 39 may be attached to the fluid chamber 6. The ring body 39 has a discharge opening 10.1
The structure may have an annular wall with a diameter approximately corresponding to 1.

FIG. 3 schematically shows this device based on JIS symbols. In FIG. 3, symbol M indicates a monitor.

The operation of this device will be explained below.

Normally, the pilot valves 27, 29 are in an inoperative state;
1st. The fluid in the third cylinder part 20.24 is discharged to the outside, and the fluid in the third cylinder part 20.24 is discharged to the outside. Since the fourth cylinder part 21.25 is under fluid pressure, the first supply opening 8 and the second supply opening 9 are closed and the first discharge opening 10 and the second discharge opening 11 are open. Ru.

Therefore, the fluid supply to the fluid chamber 6 is stopped, and the fluid chamber 6 communicates with the discharge chamber 7, so that the fluid of the actuator connected to the outlet port 3 is discharged from the discharge port 4. Fluid, for example air, is discharged from the fluid chamber 6 through the second restriction 37,38 into the discharge chamber 7 and into the discharge port 4. The pressure of the fluid is detected by the monitor flow path 33.34 from the second calibration point 7.38 through the first restriction 35.36. The fluid pressure mainly drops at the second restrictor 37, 38, and the detected pressure becomes close to the pressure at the discharge port 4.

When the pilot valve 27.29 is actuated, the piston 18
．． 22 has a larger pressure receiving area than the poppet valve bodies 12 and 15, so it is moved from the position shown in the figure and the discharge opening 10.11
is closed and the supply opening 8.9 is opened. Therefore, the supply chamber 5
communicates with the fluid chamber 6, and the fluid flows from the supply chamber 5 to the supply opening 8.
．． 9, the first aperture 35.36 and the second aperture 37.3
8 to the fluid chamber 6 and from the outlet port 3 to the actuator. The pressure drop of the fluid is mainly caused by the first restriction 35
．． 36, the pressure of which is close to that of the inlet port 2. Therefore, both valve stems [4,17
The pressure in both monitor channels 33, 34 is the same when they are activated and when they are not activated at the same time.

Looking at the case where the metal part 1 valve stem 4 does not operate for some reason and the second valve stem 17 operates, the second supply opening 9
, the first discharge opening 10h<opens, and the first supply opening 8
Then, the second discharge opening 11 is closed, and the fluid in the outlet port 3 passes through the second restriction 37, passes through the first discharge opening 10, and is discharged into the discharge chamber 7.

The fluid in the supply chamber 5 is supplied to the second supply opening 9, the second! It flows into the fluid chamber 6 through the throttle 36 and the second throttle 38. Since the flow rate discharged from the first discharge opening 10 is larger than the flow rate flowing in through the second supply opening 9, the fluid supplied to the fluid chamber 6 further passes through the second restriction 37 and then enters the first discharge opening. 10 and is not supplied to outlet port 3.

Since the pressure of the fluid supplied from the supply chamber 5 mainly decreases at the first throttle 36, the monitor flow path 34 detects a pressure close to the pressure of the artificial port 2, and the monitor flow path 33 detects the pressure close to the pressure of the discharge port 4. Detects pressure close to . Therefore, the monitor M detects the pressure difference and senses an abnormality.

The first valve stem 14 operates, and the second valve stem! The case in which valve 7 is inoperative is exactly the same as the case in which the first valve stem is inoperative, so a description thereof will be omitted.

When movement of one of the two valve stems does not occur or is delayed, the valve stem opens the supply opening (in the case of movement in the direction, the conventional valve also responds quickly, but in the case of movement in the direction of closing) However, in the example of Figure 1, in the closing direction, the normally moving valve stem opens the discharge opening.A second restriction is provided between the discharge opening and the fluid chamber. Therefore, a pressure close to the pressure at the discharge port immediately acts on the monitor flow path.A pressure close to the pressure at the inlet port acts on the other monitor flow path, so the valve stem moves in both monitor flow paths. As soon as it starts, a pressure difference is created and the monitor detects an abnormality.Therefore, the response is quick.

In contrast to the example shown in FIG. 1, the first throttle is connected to the valve stem 14 as shown in FIG. It can be formed by a ring 40, 41 fixed at +7 and a main body. That is, the first diaphragm 35 corresponds to the diaphragm 42 formed by the ring 4o and the main body 1, and the first diaphragm 36 corresponds to the diaphragm 43 formed by the ring 41 and the main body 1. Furthermore, in FIG. 4, the fluid chamber communicating with the first supply opening 8 and the fluid chamber communicating with the second supply opening 9 are separated into a first fluid chamber 44 and a second fluid chamber, respectively.
A fluid chamber 45 is formed. The first fluid chamber 44 is the second throttle 3
7' and the second fluid chamber 45 is connected to the outlet port 3 via a second restriction 38'. 2nd aperture 37°,
38' may have a simple aperture structure different from the example shown in FIG.

In the example shown in FIG. 4, other structures are the same as those in the example shown in FIG. 1, so corresponding parts are given the same reference numerals and explanations will be omitted.

Since the operation is exactly the same as the example shown in FIG. 1, the explanation will be omitted.

The present invention makes it possible to construct a double valve with a simple structure, which is capable of sensitively sensing pressure fluctuations in both the opening and closing movements of the valve stem relative to the supply and discharge openings. did it.

Since the second diaphragm can be formed as a ring, it can be easily replaced, and the detection response can be easily adjusted.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a double safety valve according to the present invention, FIG. 2 is a perspective view of a ring body integrally forming a first throttle and a second throttle,
FIG. 3 is a schematic illustration of the structure of the double safety valve according to the present invention, and FIG. 4 is a sectional view of a modification of the example shown in FIG. ■...Body 2...Supply port 3...
・Outlet port 4...Discharge port 5...Supply chamber 6, 44.45...Fluid chamber 7...Discharge chamber 8.9...Supply opening 10.11...Discharge opening 12 .13,15.16...Poppet valve body 14.17
...valve stem

Claims (1)

[Claims] (1) In a double safety valve that has two valve stems inside the main body and can detect an abnormality when one valve does not operate or is delayed in operation, a supply chamber connected to the supply port in the main body. and a fluid chamber connected to the outlet port and a discharge chamber connected to the discharge port, the fluid chamber being connected to the supply chamber by two supply openings and to the discharge chamber by two discharge openings. the supply opening and the discharge opening are each pierced by a valve stem which is coaxially formed and each individually actuated by a pilot valve; poppet valve bodies, the other poppet valve body being configured to open the valve seat of the opening when one poppet valve is seated in the valve seat of the opening; A monitor flow path is provided that opens toward the fluid chamber from the valve seat, a first restrictor is disposed between the monitor flow path opening and the fluid chamber, and the fluid chamber has a connection between the outlet port and the supply opening. A double safety valve characterized in that a second throttle is provided to partition the space between the two, and the first throttle has a larger throttle amount than the second throttle.