JP2000283081A - Gas compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas comprespor to realize reduction in a power used during high speed operation. SOLUTION: A gas compressor sucks gas through a suction port 5 and compresses the gas and discharges the gas. A suction control valve 20 is provided to close the opening of the suction port 5 during a stop of the gas compressor, increase the opening area of the suction port 5 until an operation speed reaches a given value according to the operation speed of the gas and further, and decrease the opening area of the suction port 5 according to an operation speed increased to a high value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas compressor, and more particularly, to a gas compressor which can reduce the power used during high-speed operation.

[0002]

2. Description of the Related Art Conventionally, a gas compressor used for a car air conditioner or the like is shown in a sectional view in FIG.
An X sectional view is shown in FIG. In this gas compressor, an opening end of a casing 31 is closed by a front head 32, a compressor main body 33 is housed in the casing 31, and the compressor main body 33 is connected to an electromagnetic clutch 38.

[0003] The compressor body 33 has a cylinder 49 having a substantially elliptical cylindrical inner circumference between a front side block 35 and a rear side block 36.
A rotor 42 is provided in the cylinder chamber 41 formed by the rear side block 36 and the cylinder 49.
2a and 42b rotatably support the front side block 35 and the rear side block 36.

The front side block 35 has an inlet 3
4, the casing 31 and the rear side block 3
6 form a discharge chamber 47. Cylinder 49
The rotor 42 is rotatably provided in the cylinder chamber 41 having an inner peripheral elliptical cylinder provided therein. A vane 44 is mounted on the rotor 42 in a plurality of vane grooves 43 so as to be able to advance and retreat, respectively.

[0005] The vane 44 divides the cylinder chamber 41 into a plurality of compression chambers 45.
The change of the capacity is repeated by the rotation of 2, and the low-pressure refrigerant gas sucked from the suction port 34 is compressed by the change of the capacity. The compressed high-pressure refrigerant gas is supplied to the discharge port 4
6 and is discharged to the discharge chamber 47 via the discharge valve 40.

In this gas compressor, when there is no valve device at the suction port 34, the high-pressure gas may flow backward after the operation of the gas compressor is stopped. Although there is a degree of difference depending on the operation state, since the gas flowing backward has a high temperature, hot air may be blown out from the evaporator connected to the suction port side, or the gas compressor may be reversed, which may cause a problem of the reverse sound.

In order to solve such a problem, the suction port 34
Is provided with a valve device. This valve device is called a check valve, and FIG. 2 shows a cross-sectional view. As shown in FIG. 2, the check valve 10 is composed of four parts: a guide case 1, a valve body 2, a stopper 3 and a spring 4.

During the compression operation of the gas compressor, the valve body 2 slides along the guide case 1 and is urged to the bottom of the guide case 1 by the jet flow of the refrigerant gas flowing through the suction port 5.
When the valve element 2 is located at this position, the window 1 of the guide case 1
Refrigerant gas is sucked from the suction port 5 through a.

On the other hand, when the compression operation of the gas compressor is stopped, the jet of the refrigerant gas does not flow into the suction port 5, so that
The valve body 2 slides along the guide case 1 by the force of the spring 4 and contacts the stopper 3. In this position the valve 2
When there is, the suction port 5 is closed and the backflow of the refrigerant gas from the suction port 5 to the outside is prevented.

As described above, the check valve 10 is opened by the refrigerant gas from the suction port 5, and is closed by the force of the spring when the gas compressor is stopped.

[0011]

The conventional gas compressor described above has the following problems.

As described above, the conventional gas compressor is provided with the check valve 10 at the suction port, which closes the suction port when the operation of the gas compressor is stopped to prevent backflow, and becomes fully open immediately after the start of the gas compressor. The area is almost constant.

However, in general, when the gas compressor is operating at a high speed, the cooling capacity is too high, and there is a possibility that power for exerting excess cooling capacity is used. In a conventional gas compressor, the check valve 10 is fully opened during operation, and there is no means for solving such a problem, and reduction of excess power is strongly desired from the viewpoint of energy saving.

In order to solve this problem, it is conceivable to provide a throttle in the suction port 5. However, according to this, the throttle is always throttled, and the cooling capacity decreases when the gas compressor is operated at a low speed. There is a problem of passing.

The present invention has been made in view of the above, and an object of the present invention is to provide a gas compressor which reduces the power used during high-speed operation.

[0016]

SUMMARY OF THE INVENTION Accordingly, a gas compressor according to the present invention is a gas compressor which draws gas from a suction port, compresses the gas, and discharges the compressed gas. A suction control valve that closes and increases the opening area of the suction port until a predetermined operation speed is reached according to the operation speed of the gas compressor, and further decreases the opening area of the suction port as the operation speed increases. It is characterized by having.

The suction control valve has a cylindrical case having an opening on a side surface thereof, and is slidably mounted on the case according to a position at which the suction port and the opening slide the case. And a spool provided with a communication hole for communication.

Further, the suction control valve is characterized in that when the gas compressor is stopped, the opening of the case is closed by the spool and the opening of the suction port is closed.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a gas compressor according to the present invention will be described in detail with reference to FIG.

In FIG. 1, the same members as those of the conventional member shown in FIG. 2 are denoted by the same reference numerals.

This gas compressor has a suction control valve 20 as shown in FIG. The suction control valve 20 includes a spool 21, a case 24, a stopper 26, and a spring 27.

The spool 21 has a cylindrical shape, is slidably mounted on the case 24, and is urged by a spring 27 to the position of a stopper 26 in a non-operating state (when the gas compressor is stopped). An annular gap 22 is provided in a portion where the outer diameter of the spool 21 is reduced. A communication hole 23 is provided on a side surface of the gap 22 so that the suction port 5 communicates with the gap 22. A cylindrical groove 21a that can hold and accommodate a spring 27 is provided at the bottom of the spool 21.
Is provided.

The case 24 has a spool 21 slidably mounted thereon, and an opening 25 provided on a side surface. The opening 25 includes, for example, a circular opening 25a and an opening 25b.
These openings 25a and 25b are positioned so as to communicate with the suction port 5 when the spool 21 is pushed down during operation.

Next, the operation of the suction control valve 20 from the stop of the gas compressor constructed as described above to the time of high-speed operation will be described with reference to FIG.
A description will be given using (C) during high-speed operation.

When the gas compressor is stopped, the jet of the refrigerant gas indicated by the arrow PS does not flow, and the spool 21
7 presses against the stopper 26. At the position of the spool 21, the communication hole 23 is closed by the case 24, and the opening 25 a and the opening 25 b are also closed by the spool 21. Has been prevented.

When the gas compressor is operated, the spool 21 is pushed down against the spring force of the spring 27 in accordance with an increase in the flow rate of the jet of the refrigerant gas indicated by the arrow PM. When the spool 21 is pushed down, first, the refrigerant gas flows from the opening 25a, and when the spool 21 is further pushed down, the opening 25b and the communication hole 23 are connected and the refrigerant gas flows, and the opening 25a and the opening 25b are eventually formed. It becomes fully open, and the refrigerant gas flows from both the opening 25a and the opening 25b as shown by arrows P1 and P2. At this time,
The opening area of the suction port 5 is maximized.

Further, the gas compressor operates at a high speed, and the spool 21 is further depressed against the spring force of the spring 27 in accordance with the increase in the inflow speed of the jet of the refrigerant gas indicated by the arrow PH. As the spool 21 is pushed down, the communication hole 23 is closed by the case 24, and the refrigerant gas flows only from the opening 25b as shown by the arrow P1. Thus, power reduction is performed by the throttle effect in the high-speed operation region.

In the above embodiment, the opening 25 has the opening 25a and the opening 25b.
Without being limited to this, the opening 25 is formed with the communication hole 23.
May be provided arbitrarily, and a plurality may be provided in accordance with the number of the communication holes 23, or at least one opening 25 communicating with the communication hole 23 may be provided.

Further, the gas compressor of the above-described embodiment has been described with respect to an example using a refrigerant gas. However, the present invention is not limited to this, and may be used for any compressor that compresses other gases.

As described above, it is possible to secure a desired compression capacity during low to medium speed operation of the gas compressor, and to reduce the power used during high speed operation during high speed operation.

Also, the spring can have one extremely simple structure, and the valve can be opened simultaneously with the movement of the spool so that there is no delay in valve opening.

Further, the function of the check valve can be provided without adding any parts, and the prevention of the backflow immediately after the stop of the gas compressor can be easily realized at the same time.

[0033]

According to the gas compressor of the present invention, there is provided a gas compressor for sucking gas from a suction port and compressing and discharging the gas.
When the gas compressor is stopped, close the opening of the suction port,
Up to a predetermined operating speed according to the operating speed of the gas compressor, to increase the opening area of the suction port, further provided with a suction control valve to reduce the opening area of the suction port as the operation speed becomes higher, It is possible to secure a desired compression capacity during low to medium speed operation of the gas compressor, and to reduce the power used during high speed operation during high speed operation.

The suction control valve has a cylindrical case provided with an opening on a side surface, and is slidably mounted on the case according to a position at which the suction port and the opening slide the case. Since it has a spool with a communicating hole for communication, it has an extremely simple structure and accurately secures the desired compression capacity at low to medium speed operation of the gas compressor, and reduces the power used at high speed operation at high speed operation. Can be realized.

Further, when the gas compressor is stopped, the spool closes the opening of the case and closes the opening of the suction port when the gas compressor is stopped. And backflow prevention immediately after the gas compressor is stopped can be easily realized at the same time.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a suction control valve provided in a gas compressor of the present invention. FIG.
(B) shows each operation state of the suction control valve at the time of low to medium speed operation of the gas compressor, and (C) shows the operation state of the suction control valve at the time of high speed operation of the gas compressor.

FIG. 2 is a sectional view of a check valve of a conventional gas compressor.

FIG. 3 is a sectional view of a conventional gas compressor.

FIG. 4 is a sectional view taken along line XX of FIG. 3;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 guide case 2 valve element 3 stopper 4 spring 5 suction port 10 check valve 20 suction control valve 21 spool 22 gap 23 communication hole 24 case 25 opening 26 stopper 27 spring

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F04C 29/00 F04C 29/00 J

Claims (3)

[Claims] 1. A gas compressor that draws gas from an inlet, compresses the gas, and discharges the compressed gas. A suction control valve for increasing the opening area of the suction port until the operation speed is increased, and decreasing the opening area of the suction port as the operation speed increases. 2. The suction control valve according to claim 1, wherein the suction control valve is slidably mounted on the case, and the suction port and the opening slide in the case. The gas compressor according to claim 1, further comprising a spool provided with a communication hole for communication. 3. The suction control valve according to claim 1, wherein the opening of the case is closed by the spool when the gas compressor is stopped, and the opening of the suction port is closed. Gas compressor.