JPH0244070Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field The present invention relates to a spool-type oil gate valve formed to open and close an oil passage by sliding due to compressor pressure, and is particularly suitable for improving the reliability of valve opening and closing. This relates to a spool-type oil gate valve for a compressor.

BACKGROUND ART FIG. 2 shows the structure of a spool-type oil gate valve that has been commonly used in the past.

The body main body 1 is provided with a cylinder hole 1A that slidably supports the spool valve 2, and an oil inlet 10 and an oil outlet 11 that can communicate with the cylinder hole 1A are formed perpendicular to the cylinder hole 1A. An oil supply source is connected to the oil inlet 10 via an oil filter (not shown). A plug 7 and a plug 8 are screwed into the open end portions of the body main body 1 .

The plugs 7 and 8 are each provided with a passageway through which the cylinder hole 1A communicates. The spool valve 2 consists of a first piston 3, a second piston 4, and a small diameter rod 5 that connects them.
is inserted. Further, a bottomed hole 4A is bored in the second piston 4, and a spring 9 is interposed between the bottomed hole 4A and the plug 8. The spring 9 is biased to constantly press the pool valve 2 toward the plug 7,
With the first piston 3 in contact with the plug 7, the second piston 4 of the spool valve 2 is connected to the oil inlet 10.
and is formed to block communication between the oil outlet 11 and the cylinder hole 1A. That is, the valve is held in the closed state.

A discharge port 22 of a compressor (not shown) is connected to the plug 7, and the plug 8 is connected through a small hole 23 to the cylinder side of a capacity regulator 24 connected to the compressor.

With the above structure, when the compressor is in operation, the discharge air pressure acts on the plug 7 side from the discharge port 22 as described above, so the spool valve 2 moves to the right side in the figure against the spring 9, and the small diameter rod 5 connects it to the oil inlet 10. It communicates with an oil outlet 11, and oil is sent to a predetermined oil supply section of the compressor. On the other hand, when the compressor is stopped, the discharge air pressure decreases, so the spool valve 2 moves to the left in the figure due to the reaction force of the spring 9, thereby closing the oil inlet 10. Since the closing operation of the spool valve 2 relies solely on the reaction force of the spring 9, the amount of movement of the spool valve 2 changes due to variations in the spring constant, dimensions, etc. of the spring 9, and in some cases, the valve does not close completely. Defects arise. Therefore, since oil leaks to the plug 8 side, as described above, the plug 8 and the capacity regulator 24 are connected, and the leaked oil is forced to be sucked into the cylinder of the compressor through the capacity regulator 24. That will happen. For this reason, excess oil is supplied into the cylinder when the compressor is stopped, resulting in a drawback that smooth startup of the compressor is prevented.

Problems that the invention aims to solve This invention solves the above-mentioned drawbacks, etc. It allows the spool valve to open and close smoothly, prevents oil leakage to the compressor side when closed, and reduces the starting load on the compressor. An object of the present invention is to provide a spool-type oil gate valve for a compressor that can be used in a compressor.

Means for Solving the Problems To solve this problem, the present invention uses the air pressure released when the compressor is stopped as the restoring force of the spool valve, which opens due to the discharge pressure of the compressor, to ensure the movement of the spool valve in the closing direction. The means for this purpose is a spool-type oil gate valve of the compressor, which is formed as shown in FIG.

Function: When the compressor is stopped, the compressor's discharge air pressure and spring reaction force are applied to the spool valve to reliably move the spool valve in the closing direction. This ensures complete valve closure and prevents oil leakage.

Embodiments Hereinafter, embodiments of the present invention will be described based on the drawings.

In FIG. 1, the cylinder hole 1 of the pump body 1
As described above, the spool valve 2 is slidably inserted into A, and the spool valve 2 is connected to the first piston 3 and the second piston.
The first piston 3 is formed of a piston 4, a small diameter rod 5, etc., and an O-ring 6 is fitted into the first piston 3. A bottomed hole 4A of the second piston 4 is formed. Furthermore, plugs 7 and 8 are screwed onto both sides of the cylinder hole 1A. A spring 9 is interposed between the bottom surface of the bottomed hole 4A of the second piston 4 and the plug 8. Also, the second piston 4 is connected to the oil inlet 1
0, engages with the oil outlet 11 and opens and closes these and the cylinder hole 1A. Further, an O-ring 12 that contacts the cylinder hole 1A is fitted into the second piston 4.

The blow-off valve body 14, which is arranged to hold the diaphragm valve 13, has a hole 15 that communicates with the discharge port 22 of the compressor and one side of the diaphragm valve 13, and a hole 15 that communicates with the discharge air valve 16 side of the receiver tank of the compressor. A hole 17 communicating with the other side of the diaphragm valve 13 is provided facing the hole 15, and the hole 17 is provided in a state where the hole 15 and the diaphragm valve 13 are in contact (that is, a state where the hole 15 is closed). A passageway 18 is bored through the blow-off valve body 14 that can communicate with the blow-off valve body 14 . A tee 19 is connected to the passage 18, and a tee 1 is connected to the passage 18.
A silencer 21 is connected to one outlet of 9 through a nozzle 20. Another outlet of the tee 19 communicates with the plug 8.

Next, the operation of this embodiment will be explained in more detail.

When the compressor is in operation, compressed air is introduced into the plug 7 and the hole 15 from the discharge port 22 of the compressor. As a result, the spool valve 2 is moved to communicate the oil inlet 10 and the oil outlet 11 as described above, and the diaphragm valve 13 is moved to the hole 1.
7. Move to the side where the passage 18 is closed.

When the compressor stops, the supply of compressed air to the hole 15 stops, so the diaphragm valve 13
moves to the side that closes the hole 15 and closes the hole 17 and the passage 1.
8 communicates with each other. At the same time, air from the discharge air valve 16 of the receiver tank of the compressor is introduced into the hole 17, and is sent to the plug 8 side through the passage 18 and the tee 19. As a result, the spool valve 2 is forcibly moved in the direction of closing the oil inlet 10. Of course, at this time, the reaction force of the spring 9 also acts to move the spool valve 2 in the same direction. Due to the restoring forces of both of the above, the spool valve 2 is reliably returned to the plug 7 side, and the oil supply is completely stopped. The O-ring 12 prevents oil from leaking from the small gap between the cylinder hole 4A and the spool valve 2, thereby achieving more complete oil leakage prevention. Note that a part of the emitted air sent from the tee 19 to the nozzle 20 side is silenced and emitted via the silencer 21. This ensures that unnecessary air is discharged to the outside after the spool valve 2 is returned, and unnecessary force is not applied to the spool valve 2.

As a result of the above, the spool valve 2 is smoothly reciprocated and the oil is reliably opened and closed.

In this embodiment, the blow-off valve as described above is used as a means for sending the air discharged from the receiver tank to the plug 8 side, but the invention is of course not limited to this, and compressed air is reliably supplied to the plug 8 side when the compressor is stopped. It is fine as long as it is possible.
Furthermore, although the O-ring 12 is used as the oil leakage means of the spool valve 2, it is of course not limited to the O-ring.

Effects of the invention As is clear from the above explanation, according to the present invention, the spool valve can be opened and closed smoothly, and oil leakage can be reliably prevented when the valve is closed.
It is possible to prevent oil from being introduced into the cylinder side, thereby reducing the load upon starting the compressor.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of an embodiment of the present invention, and FIG. 2 is a sectional view showing a conventional gate valve structure. 1...Body main body, 1A...Cylinder hole, 2...
Spool valve, 3...first piston, 4...second
piston, 5...small diameter rod, 6, 12...O
Ring, 7, 8...Plug, 9...Spring,
10...Oil inlet, 11...Oil outlet, 13
... diaphragm valve, 14 ... blow-off valve body, 15, 17 ... hole, 18 ... passage, 1
9...Tay, 20...Nozzle, 21...Silencer, 22...Discharge port, 23...Small hole, 24...
...capacity regulator.

Claims (1)

[Scope of utility model registration request] A spool-type oil gate valve for a compressor, characterized in that the air pressure released when the compressor is stopped is used as the restoring force of the spool valve that moves to open an oil passage due to the discharge pressure of the compressor.