JPH0413585B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a drain valve for a compressor.

[Conventional technology]

An air compressor pressurizes atmospheric air, stores it in a pressure storage tank, and sends this pressurized air from its discharge port to a device such as an air brake using air piping.

As mentioned above, when air is pressurized, water vapor in the air liquefies and accumulates as drain water in a pressure system such as a pressure storage tank or air piping. If the compressor continues to be used while this drain water is stored, the drain water will flow into each device through the piping and cause a malfunction of the device. Furthermore, the compressor itself may break down due to the influence of drain water in the pressure storage tank.

Therefore, conventional compressors are equipped with a drain outlet equipped with an on-off valve at the bottom of the pressure storage tank, and each time the compressor is stopped, this on-off valve is opened to discharge drain water from the pressure storage tank. I have to. In addition, a drain water outlet or a trap may be provided in the middle of the air piping.
Prevents drain water from being sent to the equipment through piping. This drain trap also stores drain water and is equipped with an on-off valve.
As with the pressure storage tank, the on-off valve was opened to drain the accumulated drain water.

[Problem that the invention seeks to solve]

However, the task of opening the on-off valve of the drain outlet every time the compressor is stopped is extremely troublesome and is easily forgotten. As a result, the compressor was restarted with drain water accumulated, and the drain water flowed in.
The device may malfunction and shut down.

In addition, if the equipment must be operated continuously for a long period of time, even if the on-off valve is always opened to drain the drain water when the equipment is stopped, the drain water will inevitably flow into the equipment through the air piping during operation. There is.

This invention aims to solve these problems.

[Means to solve the problem]

In order to achieve such an objective, the inventors have developed a drain valve that opens and closes a discharge passage for discharging drain water accumulated in the pressure system of a compressor, and a through-hole that forms part of the discharge passage. It is equipped with a cylindrical casing having a hole and a valve body built into the casing so as to be movable in the axial direction. It is always biased in the direction of the pressure system by a biasing means having a biasing force that is approximately equal to or slightly stronger than the lower limit pressure of the set pressure for use, and when the pressure within the pressure system is smaller than the biasing force. , closing the pressure system side mouth of the through hole;
When the biasing force becomes greater than the biasing force, the pressure is received by the surface of the valve body on the pressure system side and moved toward the discharge port, opening the port and closing the discharge port. When the outlet is closed, drain water flows into the flow path from the pressure system side, and when the valve body is moved again to the pressure system side, the drain water flows into the flow path from the pressure system side. The gist is a drain valve for a compressor, which is characterized by being adapted to discharge from an outlet.

[Effect]

With the above configuration, this drain valve allows the valve body to move between the upper and lower limits of the compressor's set pressure without releasing the pressure in the pressure system, allowing drain water to be drained while the compressor is operating. Can be discharged intermittently.

〔Example〕

Hereinafter, the present invention will be explained in detail with reference to the drawings showing one embodiment thereof.

FIG. 1 shows an embodiment of the drain valve according to the present invention, partially cut away and viewed diagonally from above. As shown in the figure, this drain valve A consists of a casing (body) 1 and a valve body (hereinafter referred to as a "first valve body (poppet)") that is movably built in the casing 1.
2). The casing 1 includes a through hole 11 serving as a drain water discharge path in its axial direction, and a partition wall 12 near one side of the middle portion of the through hole 11. The partition wall 12 is provided with a through hole 13 at its center. Female screw portions 14 and 15 are formed on the inner peripheral surface of both sides of the through hole 11 . One female threaded portion 14 is for attachment to a mounting portion on the pressure system side of the compressor. A first valve body 2 is housed between the other (discharge port side) female threaded portion 15 and the partition wall 12 so as to be movable in the axial direction of the through hole 11 . The first valve body 2 has a through hole 2 in the center.
It is a cylindrical body having a diameter of 1, and both edges thereof are chamfered into a tapered shape. These chamfered portions 21
O-rings 22, 22 are fitted into the bases of a, 21b, respectively. The first valve body 2 is held within the casing 1 by a bolt (body cap) 3 screwed into the other female threaded portion 15 and a partition wall 12 . The bolt 3 has the center part shown in Fig. 2a.
As shown in the figure, a screw hole 31 is formed. A portion of the screw hole 31 corresponding to the chamfered portion 21b has a tapered shape, and a tapered surface (sheet surface) 31a thereof is formed along the chamfered portion 21b. A cylindrical body 4 having a through hole 41 is screwed into the screw hole 31 . The cylindrical body 4 has an end portion of a through hole 41 serving as a drain water outlet 42, and a coil spring 5 is built therein. One end of the coil spring 5 is supported by a step 43 formed in the middle of the through hole 41, and the other end is wound around a spring winding part 24 formed at the end of the first valve body 2. . The first valve body 2 is always urged toward the partition wall 12 by the coil spring 5. The biasing force of the coil spring 5 is set to be approximately the same as or slightly larger than the lower limit pressure of the compressor's set pressure. The chamfered portion 21a of the first valve body 2 on the pressure system side is brought into close contact with the partition wall 12 unless pressure is applied from the pressure system side to overcome the biasing force. Chamfered portion 21a
An O-ring 22 is fitted to the base of the through hole 11, so that the through hole 11 is completely sealed and air and drain water do not leak out from the outlet 42. On the other hand, when the pressure on the pressure system side overcomes the biasing force due to the operation of the compressor, the first valve body 2 moves toward the discharge port 42 side, and the chamfered portion 21b on the discharge port 42 side changes from the taper surface 31a.
The O-ring 22 is placed in close contact with the base of the chamfered portion 21b, and is completely sealed. The biasing force of the coil spring 5 can be freely selected by changing the length of the cylindrical body 4 screwed into the screw hole 2.

The first valve body 2 has a through hole 28 formed in its center. The diameter of the through hole 28 is reduced in three steps from the pressure system side toward the discharge port 42 side.
The second valve body 7 is housed in the large diameter portion 28a so as to be movable in the axial direction of the through hole 28. The second valve body 7 includes a cylindrical portion 71 and a conical portion 72,
The cylindrical portion 71 is arranged on the pressure system side. The cylindrical portion 71 has six radial grooves 71a formed on its end surface, and vertical grooves 71b connected to the grooves 71a along the axial direction on its side peripheral surface. The groove 71a tapers from the center side of the columnar portion 71 toward the peripheral edge side. The conical portion 72 has a small diameter cylindrical spring winding portion 7 at its tip.
4 is formed. This spring winding part 74 has
A coil spring 9 is wound around the second valve body 7 to always urge the second valve body 7 toward the pressure diameter side. The coil spring 9 has a middle diameter portion 2
8b, and its end portion is supported by the edge of the small diameter portion 28c. The coil spring 9 is not particularly limited as long as its biasing force is smaller than the lower limit of the operating pressure of the compressor, but it is preferably one that can withstand a pressure of about 0.5 kg/cm ² . Note that a snap ring 29 is fitted into the mouth of the large diameter portion 28a to prevent the second valve body 7 from coming out of the through hole 28. An O-ring 75 is fitted into the base of the conical portion 72.

As described above, this drain valve A has the first valve body 2
can be easily removed from the casing by removing the bolts 3. Therefore,
Even if the valve body malfunctions due to dirt or organic matter in the drain water, it can be easily disassembled for cleaning and maintenance is easy. In Figure 2 a-c, 49
is a nut for fixing the cylindrical body 4.

Next, the operation of this drain valve A will be explained in detail with reference to FIGS. Note that the first valve body 2 is biased with 6.5Kg/cm ² and the second valve body 7 is biased with 0.5Kg/cm ² .
The operating pressure of the compressor is 6.5Kg/cm ² ~ 7.0
It is assumed that the setting is Kg/cm ² .

As shown in the figure, this drain valve A is installed by screwing the male threaded part 81a of a discharge part 81 provided in a part of the air piping 8 connected to the discharge port of the compressor into the female threaded part 14. . In this drain valve A, when the compressor is not in use, that is, when there is no pressure in the air piping 8, the first valve body 2 is pressed against the partition wall by the biasing force of the coil spring 4, as shown in FIG. 2a. The chamfered portion 21a is in close contact with 12. The second valve body 7 is brought into contact with the snap spring 29 by the biasing force of the coil spring 9. In this state, the air pipe 8
communicates with the outside via the through hole 28 of the valve body 7. When the compressor is turned on and the pressure inside the air pipe 8 becomes 0.5 kg/cm ² or more, the second valve body 7 receives the pressure at the end face of the cylindrical portion 71, as shown in FIG. 2b. , it is moved toward the discharge port 42 side. The moved second valve body 7 has an O-ring 74 fitted to the base of its conical portion 72.
is the tapered surface 31 formed on the end surface of the medium diameter portion 28b.
a, and closes the through hole 28 to prevent air from leaking from the exhaust port 42. When the pressure in the pressure system exceeds 6.5 kg/cm ² , the first valve body 2 is moved toward the discharge port 42 by the pressure, as shown in FIG. The discharge port 42 is closed by being brought into close contact with the surface 31a. While the first valve body 2 is moving, a small amount of the drain water and air in the air pipe 8 are discharged from the discharge port 42 through the groove 27 formed on the side surface of the first valve body 2. Ru. In the state shown in FIG. 2c, drain water flows into the gap between the first valve body 2 and the casing 1 and accumulates therein. That is, since the flow path to the discharge port 42 is sealed by the chamfered portion 21b, drain water and air are not discharged. The compressor pressure reaches 7.0Kg/ ^cm2 , the compressor stops operating, and the pressure gradually decreases.
When the weight reaches 6.5 kg/cm ² , the first valve body 2 returns to the state shown in FIG. 2b. Then, as described above, the drain water that has flowed into the gap between the first valve body 2 and the casing 1 and accumulated is discharged from the discharge port 42 together with the air. This drain valve A is designed to discharge the drain water accumulated in the air pipe 8 by intermittently repeating the states shown in FIG. 2b and FIG. 2c while the compressor is in operation.

Furthermore, when the compressor is stopped and the pressure inside the air pipe 8 becomes 0.5 kg/cm ² or less, the drain valve A moves until the second valve body 7 comes into contact with the snap ring 29 again, as shown in Fig. 2a. I am made to do so. Therefore, this movement of the drain valve A allows the through hole 28 of the first valve body 2 to communicate with the air pipe 8 and the discharge port 42, making it possible to discharge drain water even when the compressor is stopped. ing.

The drain valve according to the present invention is not limited to the above embodiments. For example, in the embodiments described above, the first valve body was provided with the second valve body, but it may be omitted. Although a vertical groove is formed on the side circumferential surface of the cylindrical portion of the second valve body to serve as a passage for drain water, it may be formed in a spiral shape from the end surface of the cylindrical portion along the side circumferential surface. Alternatively, a small hole may be provided that penetrates from the end surface of the cylindrical portion to the conical portion. In the above embodiment, the first and second valve bodies are biased by coil springs, but a rubber-like elastic material or the like may be used as the biasing means. In the above embodiment, the drain valve is attached to the air piping, but it may also be attached directly to the underside of the pressure storage tank of the compressor or to a drain trap provided in the air piping.

〔Effect of the invention〕

As described above, the drain valve according to the present invention has the following features:
A drain valve that opens and closes a discharge passage for discharging drain water accumulated in the pressure system of a compressor,
It is equipped with a cylindrical casing having a through hole that constitutes a part of the discharge passage, and a valve body built into the casing so as to be movable in the axial direction. The compressor is always biased in the direction of the pressure system by a biasing means having a flow path and having a biasing force that is approximately the same as or slightly stronger than the lower limit pressure of the set operating pressure of the compressor. When the pressure is smaller than the biasing force, the opening on the pressure system side of the through hole is closed, and when the pressure becomes larger than the biasing force, the pressure is received by the pressure system side surface of the valve body and flows to the discharge port side. is moved to open the port and close the discharge port, and in a state where the discharge port is closed, drain water flows into the flow path from the pressure system side. , since this drain water is discharged from the discharge port when the valve body is moved to the pressure system side again,
Even if the compressor is operated continuously for a long period of time, drain water is intermittently discharged during operation, and it is possible to eliminate failures of the device or failure of the compressor itself due to the inflow of drain water during operation.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway perspective view of one embodiment of the drain valve according to the present invention, and FIGS. 2 a to c
1 is a side sectional view explaining the operation in one usage example, in which figure a shows the state when the compressor is stopped, and figure b shows the state when the pressure of the pressure system is below the lower limit of the operating setting pressure of the compressor. The figure c shows the state in which the pressure of the pressure system ranges from the lower limit to the upper limit of the operating pressure of the compressor. A... Drain valve, 1... Casing, 2... Valve body (first valve body), 7... Second valve body, 11, 28...
...Through hole, 42...Discharge port.

Claims (1)

[Claims] 1. A drain valve that opens and closes a discharge passage for discharging drain water accumulated in the pressure system of a compressor, which comprises a cylindrical casing having a through hole forming a part of the discharge passage; and a valve body built into the casing so as to be movable in the axial direction, and the valve body has a flow path for the drain water along the axial direction, and has a pressure that is approximately the same as the lower limit of the operating pressure of the compressor. The pressure system side of the through hole is always biased in the pressure system direction by a biasing means having a rather strong biasing force, and when the pressure within the pressure system is smaller than the biasing force. When the opening of the valve body is closed and the urging force becomes greater than the biasing force, the pressure is received by the pressure system side surface of the valve body and moved to the discharge port side, opening the mouth and closing the discharge port. When the discharge port is closed, drain water flows into the flow path from the pressure system side, and the valve body moves this drain water back to the pressure system side. A drain valve for a compressor, wherein the drain valve is configured to discharge water from the discharge port when the compressor is drained. 2. The valve body has a through hole that penetrates in the axial direction,
A second valve body is built into the through hole so as to be movable in the axial direction, and the second valve body is actuated by a biasing means having a bias force weaker than the lower limit pressure of the operating design pressure of the compressor. , is always biased towards the pressure system side of the small hole to open the through hole, and when the pressure in the pressure tank becomes greater than the biasing force, it is moved to the discharge port side of the through hole. A drain valve for a compressor according to claim 1, wherein said drain valve is adapted to close said through hole.