JPH07259779A - Gas compressor - Google Patents

Abstract

PURPOSE:To prevent the generation of a high bearing at the tip of a vane during the restarting of operation as a reverse flow is prevented from occurring during the stop of operation. CONSTITUTION:A core case 51 having an oblong hole 55, a valve body 56, a spring 57 through the force of which the valve body 56 is pushed in an upward direction, a check valve 50 consisting of the stopper 60 of a valve body 51 are arranged in the suction chamber 19 of a gas compressor. A communication hole 71 with a diameter of 1-2mm to intercommunicate a suction port 21 and the suction chamber 19 is formed in the valve body 56. During operation of a gas compressor, the valve body 56 is pressed down by means of refrigerant gas, and the refrigerant gas is caused to flow through the oblong hole 55 to the suction hole 19 after the flow of it through the suction port 21. When operation is stopped, the valve body 56 is pushed up to a position above the oblong hole 55 through the force of the spring 57 to prevent the occurrence of the rapid reverse flow of high temperature high pressure refrigerant gas. Since a pressure difference between pressures in the suction port 21 and a high pressure chamber is decreased through gentle reverse flow generated by the presence of the communication hole 71, the bearing of a vane during restarting is lowered.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas compressor, for example, a volume-changeable gas compressor used in a cooling device or the like.

[0002]

2. Description of the Related Art FIG. 5 shows a system configuration of a refrigeration cycle using a gas compressor. As shown in this figure, the gas compressor 1 forms a refrigeration cycle 5 together with a condenser 2, an expansion valve 3 and an evaporator 4.

In the refrigeration cycle 5, the gas compressed by the gas compressor 1 is liquefied by releasing heat in the condenser 2 and supplied to the evaporator 4 via the expansion valve 3. This liquid is vaporized by absorbing heat in the evaporator 4, and is compressed again in the gas compressor 1.

In the gas compressor 1, for example, a vane rotary compressor, the rotor having the vanes rotates, and the gas sandwiched between the cylinder chamber containing the rotor and the vanes has its volume reduced, while the gas is reduced from the suction side to the discharge side. By being transferred to, compression work is performed.

FIG. 6 shows the structure of a gas compressor 1 for performing such a compression work. The gas compressor 1 includes a compressor body 10, a casing 11 that surrounds the compressor body 10, and a front head 12. One end of the casing 11 is open, and a flot head 12 is attached so as to seal the opening.

The compressor body 10 comprises a cylindrical cylinder block 13 having an inner peripheral surface with an elliptical cross section in the axial direction, and a front side block 14 and a rear side block 15 fixed in parallel to each other on both end surfaces thereof. The cylinder chamber 16 having an elliptic cylindrical shape is formed by these components.

Inside the cylinder chamber 16, the rotor shaft 1
A rotatable rotor 17 supported by 7a is provided. Five vanes 20 slidably held in the slit 18 are radially fitted to the rotor 17.
The end of the rotor shaft 17a is connected to a prime mover (not shown), and when the rotor 17 is driven to rotate, the five vanes 20 rotate while closely contacting the inner peripheral wall of the cylinder chamber 16 to compress the refrigerant gas. Is configured to.

A suction chamber 19 is formed on the upper side surface of the front head 12, and the evaporator 4 is provided in the suction chamber 19.
An intake port 21 for sucking the refrigerant gas to be compressed is formed. The cylinder block 13 and the front side block 14 are formed with an intake port 13a and a hole 14a for connecting the intake chamber 19 and the cylinder chamber 16 to each other. The refrigerant gas sucked into the intake port 21 is introduced into the cylinder chamber 16 through these holes 14a and the intake port 13a as shown by an arrow 23.

A discharge port (not shown) is formed in the cylinder block 13, and a hole 15b communicating with this discharge port is formed in the rear side block 15 as shown by a dotted line. A cylindrical filter 27 and a cyclone block 26 for separating lubricating oil by centrifugal force are attached to the rear side block 15.

A high pressure chamber 30 is formed between the compressor body 10 and the casing 11, and the refrigerant gas compressed in the cylinder chamber 16 has a hole 15b as shown by an arrow 28.
And is introduced into the high pressure chamber 30 through the conduction hole 26a. The discharge port 31 is provided in the casing 11 above the high-pressure chamber 30.
Is formed, the refrigerant gas in the high pressure chamber 30 is discharged to the outside through the discharge port 31 as shown by an arrow 29,
It is supplied to the capacitor 2.

In the gas compressor 1 thus constructed, when the compression operation is stopped, the high-temperature and high-pressure refrigerant gas in the high-pressure chamber 30 on the discharge side is compressed by the compressor body 10.
Through the gap between the low pressure side suction chamber 19 and the suction port 21
Will escape to the evaporator 4 side. Due to the reverse flow of the refrigerant gas, there is a problem in that the rotor 17 and the vane 20 rotate in reverse and a reverse sound is generated. Also,
The evaporator 4 is heated by the high-temperature refrigerant gas that flows backward, and the blowout temperature rises when the operation is restarted next.

In order to prevent such a problem due to the backflow of the high-temperature and high-pressure refrigerant gas, the intake port 21 of the gas compressor 1 is provided with a check valve for preventing the backflow of the high-pressure refrigerant gas. .

[0013]

FIG. 7 shows a pressure state of each part in the gas compressor 1 when the gas compressor 1 is stopped and then restarted. As shown in FIG. 7A, in the case of a gas compressor having a check valve in the suction chamber 19,
The high-pressure refrigerant gas in the high-pressure chamber 30 flows back to the suction chamber 19. For this reason, the pressure in the suction chamber 19 having a small volume approaches the pressure in the high pressure chamber 30, but the pressure in the high pressure chamber 30 does not drop so much. Since the check valve is present, the pressure of the intake port 21, which is the low pressure side, hardly rises, and the pressure is low.

When the gas compressor 1 is restarted in such a state, a large pressure difference d1 is generated between the high pressure chamber 30 and the intake port 21, so that a large surface pressure is generated at the tip of the vane 20. To do. By the way, the lubrication of the cylinder block 13, the front side block 14, and the rear side block 15 in the compressor body 10 is ensured by supplying the lubricating oil by the rotation of the rotor 17 and the vane 20. Therefore, after the gas compressor 1 is stopped, the lubrication state inside the compressor body 10 is not so good.

As described above, when the gas compressor 1 is restarted and the vane 20 having a large surface pressure at its tip is rotated in a state where the lubrication inside the compressor body 10 is not so good, the vane 20 is rotated. There was a possibility of breaking the plating at the tip. On the other hand, as shown in FIG. 7B, when the check valve is not provided, the pressure difference between the high pressure chamber 30 and the suction chamber 19 and the intake port 21 becomes smaller with the passage of time, and therefore even when the operation is restarted. Since the tip does not generate too much surface pressure, the problem of plating damage at the tip of the vane 20 does not occur, but as described above, there is the problem of reversal at the time of stop and rise of the blowout temperature at the start of operation.

Therefore, the present invention has been made to solve the above problems, and prevents the backflow at the time of operation stop and prevents the occurrence of a large surface pressure at the tip of the vane when the operation is restarted. An object is to provide a gas compressor capable of

[0017]

According to a first aspect of the present invention, there is provided a compressor main body for compressing a refrigerant gas by a volume change associated with the rotary motion of a rotating body, and a suction arranged upstream of the compressor main body. A chamber, an intake port for supplying a refrigerant gas from an evaporator to the suction chamber, and a flow path of the refrigerant gas in the suction chamber, which is arranged to allow the refrigerant gas to flow from the suction port into the suction chamber. The above object is achieved by providing the gas compressor with a check valve for limiting the reverse flow and a communication means of a fine diameter for communicating the intake port with the intake chamber.

According to a second aspect of the invention, in the gas compressor according to the first or second aspect, the communicating means has a cross-sectional area corresponding to a hole having a diameter of 1 to 2 mm. According to a third aspect of the invention, in the gas compressor according to the first or second aspect, the communication means is a communication hole arranged in the valve body of the check valve.

According to a fourth aspect of the invention, in the gas compressor according to the first or second aspect, the communicating means is
A slit provided on the outer peripheral portion of the valve body of the check valve.
According to a fifth aspect of the present invention, in the gas compressor according to the first or second aspect, the communicating means is a slit provided in a stopper that prevents the valve body of the check valve from rising.

According to a fifth aspect of the invention, in the gas compressor according to the first or second aspect, the communicating means is
The suction chamber and the suction port are directly connected holes.

[0021]

In the operation of the gas compressor, the refrigerant gas flows from the intake port through the check valve into the suction chamber and is compressed by the compressor body. On the other hand, due to the operation stop, the refrigerant gas compressed to a high pressure flows back into the suction chamber through the compressor body,
The check valve restricts the backflow to the intake port side, and the communication means having a small diameter allows the backflow from the suction chamber to the intake port gently.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the gas compressor of the present invention will be described in detail below with reference to FIGS.
The gas compressor 1 of this embodiment has substantially the same configuration as that of the gas compressor 1 described in FIG. 6 except for the vicinity of the suction chamber 19, and therefore, the same parts are denoted by the same reference numerals and the description thereof is appropriately described. I will omit it.

FIG. 1 shows the configuration around the suction chamber 19 in which a check valve is mounted in the gas compressor 1 of this embodiment. As shown in FIG. 1, a check valve 50 is arranged in the suction chamber 19 of the gas compressor 1. The check valve 50 includes a core case 51 having an open upper end, and the upper end of the core case 51 is fitted in the intake port 21. On the other hand, a support recess 52 is formed in the portion of the front head 12 that forms a part of the lower side of the suction chamber 19.
The lower end of the core case 51 is placed in the support recess 52.

An elongated hole 55 is provided near the center of the side wall of the core case 51, and the intake port 21 communicates with the intake chamber 19 through the elongated hole 55. Further, a stopper 60 is arranged on the inner wall of the intake port 21. The lower end of the stopper 60 has a notched outer periphery,
A pressing portion 61 that comes into contact with the upper end portion of the core case 51 and a valve seat portion 62 that stops the lifting of the valve body 56 are formed. The upper end of the stopper 60 is in contact with the connection member 67 for connecting the pipe from the evaporator 4 to the intake port 21. As the connecting member 67, an elbow is used in this embodiment as shown in FIG.

By attaching the connecting member 67 to the intake port 21, the stopper 60 is pushed downward and the core case 51
Is pressed by the holding portion 61 and fixed in the support recess 52. Inside the core case 51 is a valve body 56.
Is slidably arranged and a spring 57 is housed therein. The spring 57 is arranged between the inside of the valve body 56 and the bottom surface inside the core case 51, and biases the valve body 56 toward the valve seat portion 62.

The diameter of the valve body 56 varies depending on the device, but is 10 mm in the gas compressor of the illustrated embodiment, and the intake port 21 and the suction chamber 19 communicate with each other at the center thereof.
A communication hole 71 is formed as a communication means. As the communication hole 71, a hole having a diameter of about 1 mm to about 2 mm is formed.

Further, an O-ring 63, which comes into contact with the outer circumferences of the connecting member 67 and the stopper 60, is provided as a seal member on the outer circumference of the upper end portion 21a of the intake port 21. The O-ring 63 prevents the refrigerant gas from flowing out of the intake port 21 through the space between the front head 12 and the connecting member 67.

Next, the operation of the embodiment with the check valve 50 thus constructed will be described. According to the check valve 50, the valve body 56 moves downward against the force of the spring 57 due to the pressure of the refrigerant gas flowing into the intake port 21 from the connecting member 67 side during the compression operation of the gas compressor 10. To do. When the valve body 56 moves below the elongated hole 55 of the core case 51, the refrigerant gas in the intake port 21 flows into the intake chamber 19 through the elongated hole 55, and the intake port 13 a and the hole 14 are formed.
It is supplied to the cylinder chamber 16 via a. After the refrigerant gas is compressed in the cylinder chamber 16, the lubricating oil is separated by the centrifugal force in the cyclone block 26, and the condenser 2 connected to the outside from the discharge port 31 of the high pressure chamber 30.
Is supplied to.

On the other hand, when the gas compressor 1 stops the compression operation, the flow of the refrigerant gas from the intake port 21 side to the intake hole 19 side is stopped, so that the valve body 56 is pushed by the force of the spring 57. The stopper 60 moves upward from the long hole 55.
The valve seat 42 is stopped while it is in contact with the valve seat 42.

In this state where the compression operation of the gas compressor 1 is stopped, there is a high pressure difference between the high pressure chamber 30 side and the intake port 21. Therefore, the refrigerant gas in the high pressure chamber 30 flows back into the suction chamber 19 through the suction port 13a and the hole 14a. Furthermore, the refrigerant gas gradually moves from the suction chamber 19 into the core case 51 through the long hole 55 of the check valve 50 and through the communication hole 71 of the valve body 56 toward the intake port 21 side. Therefore, the pressures in the high pressure chamber 30 and the suction chamber 19 gradually decrease, and the pressures at the intake port 21 gradually increase.

In the case of the conventional check valve, as shown in FIG. 7A, when the gas compressor 1 is stopped and restarted, the high pressure chamber 3
A large pressure difference d1 occurs between 0 and the intake port 21. On the other hand, when the check valve 51 of this embodiment in which the valve body 56 is provided with the communication hole 71 is used, the pressure difference between the high pressure chamber 30 and the intake port 21 is as shown in FIG. It is as small as d2. Therefore, the surface pressure generated at the tip of the vane 20 is comparatively small, and even if the compressor main body 10 is restarted in a poorly lubricated state, the plating at the tip of the vane 20 is not damaged.

Further, since the surface pressure is suppressed when the lubrication condition is not so good, the wear of the tip of the vane 20 can be reduced. Furthermore, surge can be prevented. Further, when the check valve is not attached, the pressure of each part changes rapidly as shown in FIG. 7 (b). On the other hand, in the present embodiment, the pressure of each part changes gently, and after the gas compressor 1 is stopped, the high-pressure and high-temperature refrigerant gas does not suddenly flow back to the intake port 21 side and the evaporator 4 side.
Therefore, the rotor 17 and the vanes 20 do not rotate in reverse and a reverse sound is generated, and the evaporator 4 is not heated by the high temperature refrigerant gas flowing backward.

In the embodiment described above, the valve body 56 is provided with the communication hole 71 as a communication means for communicating the suction chamber 19 and the intake port 21 with each other, whereby the high pressure chamber 30 and the intake air when the gas compressor 1 is stopped. Although the pressure difference with the mouth 21 is made small, the present invention is not limited to this configuration, and various modifications are possible.

For example, as shown in FIG. 2, as a communicating means, a slit 72 may be provided on the outer peripheral surface of the valve body 56 for communicating the suction chamber 19 and the suction port 21. The slit 72 in this case also has a diameter of about 1 mm to 2 mm. As a result, when the gas compressor 1 is stopped, the refrigerant gas on the high pressure chamber 30 side enters the core case 51 of the check valve 51 from the suction chamber 19 and gradually passes through the slits 72. By moving to the suction hole 21 side,
The pressure difference becomes small.

Further, as shown in FIG. 3, a communicating means may be provided in the stopper 60 that holds down the core case 51 of the check valve 50 and prevents the valve body 56 from rising. Note that FIG.
In the above, the slit 73 provided at the lower end of the stopper 60 is used as the communicating means, but the slit may be provided at the upper end, and the hole provided in the stopper 60 allows the intake chamber 2 to be connected.
1 and the suction chamber 19 may be directly provided with a communication hole. Further, the hole provided at the side of the stopper 60 and the suction chamber 1 may be provided.
A communication means may be formed by a slit connecting 9 and 9.

Further, as shown in FIG. 4, the stopper 60 is provided with a direct connection hole 74 that directly connects the suction chamber 19 and the suction port 21.
Alternatively, it may be provided on the front head 12.

[0037]

As described above, according to the present invention,
Since the communication means having a fine diameter that connects the intake port and the suction chamber is provided, it is possible to prevent a backflow when the operation is stopped and prevent a large surface pressure from being generated at the tip of the vane when the operation is restarted.

[Brief description of drawings]

FIG. 1 is a cross-sectional configuration diagram around a suction chamber to which a check valve of a gas compressor according to an embodiment of the present invention is attached.

FIG. 2 is a cross-sectional configuration diagram of the vicinity of an intake chamber to which a check valve is attached in another embodiment of the gas compressor of the above.

FIG. 3 is the same as the above, in yet another embodiment of the gas compressor,
FIG. 3 is a cross-sectional configuration diagram around a suction chamber to which a check valve is attached.

FIG. 4 is the same as above, in yet another embodiment of the gas compressor,
FIG. 3 is a cross-sectional configuration diagram around a suction chamber to which a check valve is attached.

FIG. 5 is an explanatory diagram illustrating a refrigeration cycle.

FIG. 6 is an overall configuration diagram of a gas compressor.

FIG. 7 is an explanatory diagram showing a pressure state of each part after the gas compressor is stopped and restarted.

[Explanation of symbols]

 1 Gas Compressor 10 Compressor Main Body 11 Casing 12 Front Head 13 Cylinder Block 14 Flot Side Block 15 Rear Side Block 16 Cylinder Chamber 17 Rotor 19 Suction Chamber 20 Vanes 21 Suction Port 30 High Pressure Chamber 51 Core Case 55 Long Hole 56 Valve Body 57 Spring 60 Stopper 61 Presser part 62 Valve seat part 63 O-ring 67 Connection member 71 Communication hole 72, 73 Slot 74 Direct connection hole

Claims (6)

[Claims] 1. A compressor main body for compressing a refrigerant gas by a volume change accompanying the rotational movement of a rotating body, a suction chamber arranged upstream of the compressor main body, and a refrigerant gas from an evaporator in the suction chamber. And an intake port for supplying, and arranged on the flow path of the refrigerant gas in the suction chamber,
A check valve that allows the refrigerant gas to flow from the intake port into the intake chamber and restricts the reverse flow thereof; and a communication means having a fine diameter that connects the intake port and the intake chamber. Gas compressor 2. The gas compressor according to claim 1, wherein the communicating means has a cross-sectional area corresponding to a hole having a diameter of 1 to 2 mm. 3. The gas compressor according to claim 1, wherein the communication means is a communication hole provided in the valve body of the check valve. 4. The gas compressor according to claim 1 or 2, wherein the communicating means is a slit provided on an outer peripheral portion of a valve body of the check valve. 5. The gas compressor according to claim 1, wherein the communication means is a slit provided in a stopper that suppresses the rise of the valve body of the check valve. 6. The gas compressor according to claim 1, wherein the communication means is a direct connection hole that directly connects the suction chamber and the suction port.