JPH11182480A - Rotary compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce blow-back sounds, etc., generated in the body of a compressor by suppressing counter-flow of a compressed gas discharged from the compressor body to a tank when the compressing operation is stopped. SOLUTION: The discharge port 8 of the body 1 of a compressor is connected with an after-cooler 10 through a discharge piping 11, and the after-cooler 10 is connected with an air tank 12 through the discharge piping 11. The first check valve 14 is installed between the discharge port 8 and after-cooler 10, and a valve seal made of a resin material such as polyethylene tetrafluoride is installed on the valve element of this check valve 14. Further the second check valve 20 is installed between the after-cooler 10 and air tank 12, and a valve seal made of a metal material having excellent heat resistance is installed on the valve element of the second check valve 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rotary compressor suitable for use in, for example, an air compressor or a vacuum pump.

[0002]

2. Description of the Related Art Generally, scroll compressors, vane compressors, screw compressors and the like are known as rotary compressors. Among these, for example, a scroll compressor used for a scroll air compressor or the like includes a compressor body that defines a compression chamber between a fixed scroll and an orbiting scroll, and is sucked into the compression chamber from a suction port. The air is discharged as compressed air from the discharge port to an external air tank.

In this type of prior art, an aftercooler is provided between a compressor body and an air tank, and high-temperature compressed air discharged from the compressor body is cooled in advance by the aftercooler and stored in the air tank. Thus, the amount of compressed air stored in the air tank is increased.

[0004]

By the way, in the scroll type air compressor according to the prior art described above, the discharge pipe connecting between the discharge port of the compressor body and the air tank is provided with:
By providing a check valve near the air tank, compressed air in the air tank is prevented from flowing backward through the discharge pipe and leaking when the compression operation is stopped.

[0005] However, in this conventional technique, the compressed air remaining in the discharge pipe when the compression operation is stopped is
Since it flows backward from the discharge port toward the compression chamber of the compressor body,
The flow of the backflowed air (hereinafter referred to as "backflow air") causes the orbiting scroll to rotate at a high speed in a direction opposite to that during operation, thereby imposing an extra load on the compressor body and shortening the life of the device. Problem.
Further, as the orbiting scroll rotates in the reverse direction, the backflow air is blown back toward the outside from the suction port. There is a problem.

Therefore, in order to solve such a problem, the check valve is provided at a position near the discharge port of the compressor body so that the backflow of the compressed air in the air tank and the compression remaining in the discharge pipe are prevented. A method is known in which both the backflow of air and the backflow are suppressed by the check valve.

However, in this case, during the compression operation, the check valve is apt to be deteriorated due to the influence of the heat of compression by the compressed air from the discharge port. There is a problem that the function of the valve is impaired.

There is also known a method in which a throttle such as a mesh plate is provided at the suction port to reduce the flow velocity of the backflow air blown back from the suction port by the mesh plate.

However, if a throttle such as a mesh plate is provided at the suction port, the amount of suction air sucked into the compression chamber from the suction port during the compression operation is greatly reduced by the mesh plate. There is a problem that the performance is deteriorated and the mounting structure of the mesh plate to be mounted on the suction port is complicated.

The present invention has been made in view of the above-mentioned problems of the prior art. In the present invention, when the compression operation is stopped, the compressed air discharged from the compressor body toward the tank flows back into the compressor body. A check valve reduces the amount of excess load applied to the compressor body, improving the performance of the device, and reducing the sound of backflow air from the discharge port. It aims to provide a compressor.

[0011]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a compressor body for compressing a gas by a rotational motion, an aftercooler for cooling the compressed gas compressed by the compressor body, and The present invention is applied to a rotary compressor having a tank for storing a compressed gas cooled by an aftercooler.

A feature of the structure adopted by the first aspect of the present invention is that a compressed gas is allowed to flow between the compressor body and the aftercooler toward the aftercooler,
A first check valve for shutting off a reverse flow is provided, and between the aftercooler and the tank, cooled compressed gas from the aftercooler is allowed to flow toward the tank. A second check valve for shutting off the flow is provided.

With this configuration, when the compression operation is stopped, the first problem is that the compressed gas remaining between the compressor body and the tank leaks to the compressor body side and flows backward.
Can be blocked by the check valve. The second check valve can prevent the compressed gas in the tank from leaking to the compressor body and flowing backward.

Here, even if the compressed gas remaining between the compressor body and the tank slightly leaks to the compressor body side via the first check valve and flows backward, at this time, the compressor body The flow rate of the compressed gas flowing back to the side can be reduced by the first check valve.

Further, since the compressed gas cooled by the aftercooler flows through the second check valve, the second check valve can always be maintained at a low temperature. Can be prevented from being deteriorated under the influence of compression heat due to the compressed gas discharged from the compressor body.

According to the second aspect of the present invention, the first check valve includes a valve case formed of a metal material and having a valve seat, and a valve body separated from and seated on the valve seat of the valve case. The valve seal of the valve body is formed of a metal material integral with or separate from the valve body.

With this configuration, it is possible to prevent the valve seal of the first check valve from being deteriorated during compression operation due to the influence of the heat of compression by the compressed gas discharged from the compressor body.

Further, in the invention according to claim 3, the second check valve includes a valve case formed of a metal material and having a valve seat, and a valve body separated from and seated on the valve seat of the valve case. The valve seal of the valve body is formed of a resin material or a rubber material.

Thus, when the second check valve is closed, the valve seal made of a resin material or a rubber material is seated on the valve seat of the valve case, thereby providing a seal between the valve seal and the valve seat surface. Can be enhanced.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a rotary compressor according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings, taking as an example a case where the rotary compressor is applied to a scroll air compressor. Here, FIGS. 1 to 3 show a first embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a scroll-type compressor main body. As shown in FIG.
A, a casing 2 having a closed cylindrical shape, a drive shaft 3 rotatably provided on a bearing portion 2A of the casing 2 with a distal end serving as a crank 3A, and rotatably supported by the crank 3A of the drive shaft 3. The orbiting scroll 4 and a fixed scroll 6 provided integrally with the opening end of the casing 2 and defining a plurality of compression chambers 5, 5,. .

The fixed scroll 6 is provided with a suction port 7 opening to the compression chamber 5 on the outer peripheral side and a discharge port 8 opening to the compression chamber 5 on the inner peripheral side (center side). Is provided with a suction filter 9. And the compressor body 1
Is to discharge compressed air toward the discharge port 8 while compressing the air sucked from the suction port 7 in each compression chamber 5 by the revolving (rotating) movement of the orbiting scroll 4.

Reference numeral 10 denotes a compressor body 1 through a discharge pipe 11.
The aftercooler 10 is connected to the discharge port 8 side, and the aftercooler 10 is for cooling the high-temperature compressed air discharged from the discharge port 8.

Reference numeral 12 denotes a pipe 1 on the discharge side of the aftercooler 10.
3 through the air tank 12
Is for storing the compressed air cooled from the aftercooler 10.

A first check valve 14 is provided between the discharge port 8 of the compressor body 1 and the aftercooler 10 and provided in the discharge pipe 11. The check valve 14 is, as shown in FIG. It is disposed near the discharge port 8.

The check valve 14 is made of a metal material, and is provided with an inlet port 15A, an outlet port 15B and a screw hole 15C.
5, a partition 16 provided with a valve seat 16A and an opening 16B, and a screw 17 screwed into a screw hole 15C of a valve case 15 and having a guide hole 17A formed in the axial direction.
And a valve body 18 integrally formed as a stepped cylindrical body from the cylindrical portion 18A and the disk portion 18B, and the cylindrical portion 18A side is slidably inserted into the guide hole 17A of the screw 17. I have. The check valve 14 has an inflow port 15A connected to the discharge port 8 side, and an outflow port 15B connected to the aftercooler 10 side.

Here, a valve seal 19 is provided integrally with the disc portion 18B of the valve body 18 at a position facing the valve seat 16A. The valve seal 19 is formed as an annular body from a metal material or the like having excellent heat resistance, and closes the opening 16B by sitting on the valve seat 16A.

When the compressed air from the discharge port 8 flows into the inflow port 15A, the check valve 14 holds the valve element 18 at the valve open position as shown by a dashed line in FIG. The configuration allows the compressed air to flow in the discharge pipe 11 in the direction of arrow A from the inflow port 15A side to the outflow port 15B side. When the compressed air flows through the discharge pipe 11 in the direction indicated by the arrow B in the direction opposite to the direction indicated by the arrow A, the valve element 18 is set to the valve closing position as shown by the solid line in FIG. The configuration is such that the flow of the compressed air in the direction of arrow B is blocked.

Reference numeral 20 denotes an aftercooler 10 and an air tank 12
The check valve 20 is disposed in the vicinity of the air tank 12 as shown in FIG.

The check valve 20 is formed of a metal material in substantially the same manner as the check valve 14, and is formed of an inflow port 21A,
A valve case 21 provided with an outflow port 21B and a screw hole 21C, and a part of the valve case 21;
A, a partition wall 22 having an opening 22B formed therein, a screw 23 screwed into a screw hole 21C of the valve case 21 and having a guide hole 23A formed therein, a cylindrical portion 24A and a disk portion 24B.
And a valve element 24 having

Here, a valve seal 25 is provided integrally with the disc portion 24B of the valve body 24 at a position facing the valve seat 22A. The valve seal 25 is formed as an annular body from a heat-resistant resin material, for example, a tetrafluoroethylene-based polymer material, and closes the opening 22B by sitting on the valve seat 22A. Note that the valve seal 25 may be formed from a rubber material.

The check valve 20 is connected to the aftercooler 10.
When the compressed air cooled from the air flows into the inflow port 21A, the compressed air flows out of the inflow port 21A by holding the valve body 24 at the valve opening position as shown by the dashed line in FIG. Discharge pipe 1 to port 21B
1 is allowed to flow in the direction of arrow A.
When the compressed air flows in the discharge pipe 11 in the direction indicated by the arrow B in the direction opposite to the direction indicated by the arrow A, the valve element 24 is turned off as shown in FIG.
By setting the valve at the valve closing position as shown by the solid line therein, the configuration is such that the flow of the compressed air in the direction of arrow B is blocked.

The scroll type air compressor according to the present embodiment is constructed as described above, and its operation will be described next.

First, when the drive shaft 3 is rotationally driven by a drive source (not shown) such as a motor, the rotation is transmitted from the crank 3A of the drive shaft 3 to the orbiting scroll 4 to have a constant turning radius. Perform a swivel motion. The compression chambers 5, 5,... Defined between the orbiting scroll 4 and the fixed scroll 6 by this orbiting motion are continuously reduced toward the center side, and the air sucked through the suction port 7 is sequentially compressed. The compressed air is discharged toward the discharge port 8 and stored in the air tank 12 via the first check valve 14, the aftercooler 10, and the second check valve 20.

When the compression operation is stopped, the second check valve 20 provided between the aftercooler 10 and the air tank 12 is closed, so that the compressed air in the air tank 12 is released from the compressor body 1. Can be prevented by the check valve 20 and the compressor body 1
Compressed air from the storage can be kept. Here, in the check valve 20, since the valve seal 25 is formed of a resin material or the like, the sealing property between the valve seal 25 and the valve seat 22A can be improved when the valve is closed.

Further, when the compression operation is stopped,
When the check valve 14 provided between the discharge port 8 of the compressor main body 1 and the aftercooler 10 is closed together with the check valve 20, the compressed air remaining in the discharge pipe 11 is released from the compressor main body 1
It can be prevented from leaking to the side.

Here, since the check valve 14 has the valve seal 19 formed of a metal material, the discharge pipe 11 is closed when the check valve 14 is closed.
The compressed air remaining inside may leak slightly from the space between the valve seat 16A and the valve seal 19 to the compressor main body 1 side and flow backward. However, even if the compressed air remaining in the discharge pipe 11 flows back to the compressor body 1 in this manner, the flow rate of the compressed air flowing back can be sufficiently reduced by the check valve 14.

Therefore, according to the present embodiment, when the compression operation is stopped, it is possible to prevent the orbiting scroll 4 from rotating in the reverse direction at a high speed as described in the related art.
The extra load applied to the device can be minimized, and the life of the device can be extended. Then, it is possible to reduce noise such as a blowback sound generated from the suction port 7.

Further, it is not necessary to provide a mesh plate or the like on the suction port 7 side as described in the prior art, and the amount of intake air sucked into the compression chamber 5 from the suction port 7 during the compression operation can be increased. Thus, the compression performance of the apparatus can be improved. Further, an attaching means for attaching a mesh plate or the like becomes unnecessary, and the overall configuration of the apparatus can be simplified.

Further, since the valve element 18 of the first check valve 14 is provided with a valve seal 19 made of a metal material, the valve seal 19 is capable of generating high-temperature compression heat generated by compressed air from the discharge port 8. Deterioration due to the influence can be prevented, whereby the reliability of the check valve 14 as a backflow prevention means for preventing backflow of the compressed air can be improved.

On the other hand, in the second check valve 20, the valve seal 25 is made of a resin material having relatively low heat resistance such as ethylene tetrafluoride. However, since the high-temperature compressed air from the discharge port 8 flows through the check valve 20 in a state cooled in advance by the aftercooler 10, the valve seal 25
Can be maintained at a low temperature. As a result, the valve seal 25 can be prevented from being deteriorated under the influence of the heat of compression, similarly to the valve seal 19, and the reliability of the check valve 20 as a backflow prevention means for preventing backflow of compressed air can be improved. Can be.

Next, FIG. 4 shows a second embodiment according to the present invention. The feature of the present embodiment is that the first body is provided between the discharge port 8 of the compressor body 1 and the aftercooler 10. The first check valve 3 is replaced with the first check valve 14 described in the embodiment.
1 is provided, and the entire valve body 32 of the check valve 31 is formed of a metal material.

Here, the check valve 31 is constructed in substantially the same manner as the first check valve 14 according to the first embodiment, and the valve element 32 used for the check valve 31 is a cylindrical member 32A. It is formed as a stepped cylinder from the disc portion 32B.

However, the entire valve body 32 including the cylindrical portion 32A and the disk portion 32B is formed of a heat-resistant metal material or the like, similarly to the valve seal 19 according to the first embodiment. This is different from the first embodiment in the point. As a result, the valve body 32 is
End face is directly separated and seated on the valve seat 16A of the valve case 15,
It is configured as a valve seal that seals between the valve seat 16A.

Thus, also in the present embodiment configured as described above, it is possible to obtain substantially the same operation and effect as in the first embodiment.

Next, FIG. 5 shows a third embodiment according to the present invention. The feature of this embodiment is that the first cooler is provided between the discharge port 8 of the compressor body 1 and the aftercooler 10. The first check valve 4 is replaced with the first check valve 14 described in the embodiment.
1 is provided so that the entire valve body 42 of the check valve 41 is formed in a flat plate shape from a metal material.

Here, the check valve 41 has substantially the same configuration as the first check valve 14 according to the first embodiment, but the valve element 42 used for the check valve 41 is It is formed as a thin plate made of a metal material having excellent heat resistance, and one end thereof is fixed to a valve seat 16A of the valve case 15. As a result, the valve body 42 is configured as a valve seal that separates and seats on the valve seat 16A with the other end side being a free end, and seals between the valve seat 16A. Further, the guide hole 17A described in the first embodiment is eliminated from the screw 43 used for the check valve 41.

Thus, also in the present embodiment having such a configuration, it is possible to obtain substantially the same operation and effect as in the first embodiment.

In the first embodiment, the valve 1
Although the valve seals 19 and 25 are provided on the sides 8 and 24, respectively, the valve seals 19 and 25 are replaced with the valve seals 19 and 25, for example.
25 may be provided on the valve seats 16A, 22A side of the valve cases 15, 21, and the valve bodies 18, 24 may be separated and seated with respect to this valve seal.

In each of the above embodiments, a scroll type air compressor has been described as an example of a rotary type compressor. However, the present invention is not limited to this, and may be applied to a vane type compressor, a screw type compressor and the like. The present invention may be applied to a compressor for compressing a gas other than air, and may also be applied to a vacuum pump or the like.

[0051]

As described above, according to the first aspect of the present invention, the first check valve is provided between the compressor body and the aftercooler, and the second check valve is provided between the aftercooler and the tank. Since the stop valve is provided, the second check valve can always be maintained at a low temperature during the compression operation, and the second check valve is affected by the heat of compression by the compressed gas discharged from the compressor body. It can be prevented from being deteriorated by receiving.

Therefore, when the compression operation is stopped and the first and second check valves are closed, the compressed gas remaining between the compressor body and the tank passes through the first check valve. Even if the gas leaks slightly to the compressor body and flows backward, the flow rate of the gas flowing back to the compressor body at this time can be sufficiently reduced by the first check valve. As a result, it is possible to prevent the compressor body from rotating backward at a high speed as described in the related art, and to minimize the extra load applied to the compressor body, thereby extending the life of the compressor. And
Noise such as blowback noise generated from the compressor body can be reduced.

According to the second aspect of the present invention, the check valve has a structure in which the valve seal of the valve body is formed of a metal material integral with or separate from the valve body. Deterioration due to the influence of compression heat can be prevented, and the reliability of the check valve as a backflow prevention means for preventing backflow of the compressed gas can be improved.

Further, in the third aspect of the present invention, the second check valve has a structure in which the valve seal of the valve body is formed of a resin material. The sealing performance can be improved, and the reliability of the second check valve as the backflow prevention means can be improved in the same manner as the third aspect of the present invention.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a scroll type air compressor according to a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing a first check valve in FIG. 1;

FIG. 3 is an enlarged sectional view showing a second check valve in FIG. 1;

FIG. 4 is a cross-sectional view showing a first check valve of a scroll air compressor according to a second embodiment of the present invention.

FIG. 5 is a cross-sectional view illustrating a first check valve of a scroll air compressor according to a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor main body 4 Orbiting scroll 5 Compression chamber 10 Aftercooler 12 Air tank 14,31,41 First check valve 15,21 Valve case 16A, 22A Valve seat 18,24,32,42 Valve body 19,25 Valve seal 20 Second check valve

Claims (3)

[Claims] A compressor for compressing gas by a rotary motion; an aftercooler for cooling the compressed gas compressed by the compressor body; and a tank for storing the compressed gas cooled by the aftercooler. In the rotary compressor, a first check valve that allows a compressed gas to flow toward the aftercooler and blocks a reverse flow is provided between the compressor body and the aftercooler, Between the aftercooler and the tank, a configuration is provided in which a second check valve for allowing the compressed gas cooled from the aftercooler to flow toward the tank and blocking the flow in the opposite direction is provided. Features a rotary compressor. 2. The valve according to claim 1, wherein the first check valve includes a valve case formed of a metal material and having a valve seat, and a valve body separated from and seated on the valve seat of the valve case. 2. The rotary compressor according to claim 1, wherein the rotary compressor is formed of a metal material integral with or separate from the valve body. 3. The second check valve includes a valve case formed of a metal material and having a valve seat, and a valve body separated from and seated on the valve seat of the valve case. 2. The rotary compressor according to claim 1, wherein the rotary compressor is formed of a resin material or a rubber material.