JP2004124830A - Scroll compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance efficiency of a compressor by reducing a suction pressure loss occurring due to a check valve arranged to a suction part of the compressor, and by ensuring sufficient suction passage area of a coolant gas. <P>SOLUTION: This compressor comprises a suction pipe 13 which is connected to a suction chamber 7 of a compression mechanism part comprised of a fixed scroll and a turning scroll, and supplies gas to be compressed to the suction chamber. Further, the check valve is provided which prevents compressed gas in the compression mechanism part from flowing back to a suction side. The check valve comprises: a valve element 18 arranged inside the suction chamber 7 to be capable of closing a suction port; a guide part 19 connected to the valve element through a support rod 20 and arranged to be capable of reciprocating motion inside the suction pipe 13; and a spring 17 arranged inside the suction pipe to urge the guide part such that the valve element closes the suction port. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a scroll compressor having a check valve on a suction side for preventing reverse rotation of an orbiting scroll, and is particularly suitable for a scroll compressor used for air conditioning or freezing.
[0002]
[Prior art]
2. Description of the Related Art As a conventional scroll compressor, for example, there is one described in Patent Document 1. This prior art device includes a compression mechanism portion disposed at an upper portion in a closed container and configured by a fixed scroll and a revolving scroll, an electric motor portion disposed at a lower portion in the closed container, a frame, and a power of the electric motor portion to a revolving scroll. Its main components are a transmission crankshaft and an Oldham ring (rotation prevention mechanism). A suction pipe (suction pipe) connected to the refrigeration cycle is press-fitted into a suction port of the fixed scroll.
[0003]
When the crankshaft is rotated by the rotation of the electric motor and the orbiting scroll orbits, the refrigerant gas is sucked from the suction pipe, gradually compressed in the compression chamber of the compression mechanism, and discharged from the discharge port into the closed container. The released refrigerant gas is supplied from the discharge pipe to the refrigeration cycle. When the compressor is operated, the refrigerant gas is sucked from the suction pipe, and the force of the sucked refrigerant gas causes the valve body of the check valve provided in the suction chamber to be pushed downward against the spring force of the spring. The refrigerant gas is drawn into the suction chamber of the compression mechanism and is compressed.
[0004]
When the compressor stops operating, the refrigerant gas being compressed in the compression chamber and the high-pressure refrigerant gas in the closed vessel try to flow back to the suction side, and a check valve is provided by a spring provided below the check valve body. The valve body is pushed upward, and the check valve body blocks the suction port, so that the backflow of the refrigerant gas is prevented. At the same time, the refrigerating machine oil in the closed container is prevented from being taken out of the compressor from the suction pipe.
[0005]
[Patent Document 1]
JP-A-7-77182
[Problems to be solved by the invention]
In the above-described conventional scroll compressor, the presence of the check valve itself installed in the suction chamber in the fixed scroll becomes a physical obstacle, and the pressure loss when sucking the refrigerant gas into the compression chamber increases because the suction passage is narrowed. Thus, there is a problem that the efficiency of the compressor is reduced. Further, in order to increase the passage area in the fixed scroll in which the check valve is installed, it is conceivable to make the suction chamber large, but in that case, the outer diameter and height of the compressor must be increased. However, there is a problem in that the scroll compressor becomes large in size, which deteriorates the mountability in an air conditioner and increases the cost.
[0007]
An object of the present invention is to provide a scroll compressor capable of ensuring a sufficient refrigerant gas suction passage area in a compressor suction chamber and reducing suction pressure loss without increasing the size of the compressor.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a compression mechanism having a fixed scroll and an orbiting scroll, in which spiral wraps formed upright on the base plate are meshed with each other to form a compression chamber. An electric motor that drives the orbiting scroll of the compression mechanism via a crankshaft, a frame including a bearing that supports the crankshaft, and a rotation prevention mechanism that prevents the orbiting scroll from rotating with respect to the frame, In a scroll compressor comprising: a sealed container accommodating each of the above-described elements; and a suction pipe connected to a suction chamber of the compression mechanism for supplying a gas to be compressed to the suction chamber. A check valve for preventing the compressed gas from flowing back to the suction side through the suction pipe and closing the suction port, the check valve closing the suction port of the compression mechanism suction chamber. A valve body provided to be capable of being provided and provided in the suction chamber, a guide portion connected to the valve body by a connecting member and provided so as to be reciprocally movable in the suction pipe, and the valve body provided in the suction pipe. And an urging means for urging the guide portion so as to close the suction port of the suction chamber.
[0009]
Here, it is preferable that the connecting member that connects the valve body and the guide portion is formed of a thin support rod. Further, it is preferable that the urging means is a coil spring arranged such that the support rod is located at the center thereof.
[0010]
Another feature of the present invention is a compression mechanism portion having a fixed scroll and an orbiting scroll, in which spiral wraps formed upright on the base plate are engaged with each other to form a compression chamber, and a compression mechanism. An electric motor for driving the orbiting scroll of the section via a crankshaft, a frame having a bearing for rotatably supporting the crankshaft, and a rotation for orbiting the orbiting scroll with respect to the frame while maintaining an angular positional relationship with the frame. A scroll compressor comprising: a prevention mechanism; a sealed container accommodating each of the above-described elements; and a suction pipe connected to a suction part of the compression mechanism part and supplying a refrigerant gas to be compressed to the suction part. A check valve for preventing the refrigerant gas and the refrigerating machine oil in the compression mechanism from flowing backward to the suction pipe and flowing out, and the check valve is provided with the compression mechanism A valve body provided reciprocally in the suction chamber and configured to close the suction port, a guide unit connected to the valve body by a support rod, and provided in the suction pipe so as to be able to reciprocate in the suction pipe; An elastic member that urges the guide portion upstream so that the valve element closes the suction port of the suction chamber, and the check valve is operated by the elastic member when the compressor is stopped. By closing the suction port, the compressed refrigerant gas flows backward to the suction side to reverse the orbiting scroll and to prevent the refrigerant gas and refrigeration oil from flowing back to the upstream side, and is sucked when the compressor is operating. The valve body is moved to the bottom of the suction chamber by the refrigerant gas, so that a sufficient suction passage area can be secured.
[0011]
Here, the elastic member may be a coil-shaped spring, and may be disposed so as to urge the guide portion upward. The support rod is located substantially on the center axis of the check valve and connects the valve body and the guide portion. The length of the support rod is determined by the reciprocating movement of the valve body in the suction chamber. It is good to decide so that it can be in close contact with both the suction chamber bottom and the suction port.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a view for explaining the overall configuration of a scroll compressor showing one embodiment of the present invention, and FIG. 2 is an enlarged sectional view of a main part around a check valve in FIG.
[0013]
A compression mechanism section including a fixed scroll 2 and an orbiting scroll 3 and the like are accommodated in an upper portion of the closed container 1, and an electric motor portion is accommodated in a lower portion. Reference numeral 4 denotes a frame, and 11 denotes an Oldham ring (rotation prevention mechanism). A suction pipe (suction pipe) 13 connected to a refrigeration cycle is press-fitted into the suction chamber 7 of the fixed scroll 2.
[0014]
Each of the fixed scroll 2 and the orbiting scroll 3 is formed with a spiral wrap standing upright on the base plate surface, and a compression chamber 6 is formed by engaging the wrap portions with each other inward. An eccentric portion 5a of the crankshaft 5 is rotatably engaged with the boss portion 3a of the orbiting scroll 3. A key groove 3b is formed on the opposite side of the base plate of the orbiting scroll 3 from the lap side, and a key groove 4a is also formed on the frame 4. The key part of the Oldham ring 11 is slidable in these key grooves 3b and 4a. Is engaged.
[0015]
The frame 4 has a seat surface for supporting the base plate of the orbiting scroll 3 and a surface on which the Oldham ring 11 slides, and a thrust surface 21 and a main bearing 22 for supporting the crankshaft 5 are provided. . The outer peripheral side surface of the frame 4 is fixed to the closed container 1 by spot welding, and the outer peripheral portion is fastened to the fixed scroll 2 by bolts. A rotor 10 constituting an electric motor is fitted to the crankshaft 5 by press-fitting or the like, and a stator 9 constituting the electric motor is fixed in the closed casing 1 by shrink fitting or the like.
[0016]
When the rotor 10 receives the rotational force, the crankshaft 5 rotates, and the orbiting scroll 3 orbits without rotating by the Oldham ring 11. The refrigerant gas is sucked from the suction pipe 13 into the suction chamber 7 of the fixed scroll 2 by the orbiting movement of the orbiting scroll 3, and the sucked refrigerant gas is gradually compressed in the compression chamber 6 and discharged from the discharge port 8 to the closed container 1. It is discharged into the chamber 23. The discharged refrigerant gas cools the motor unit and is supplied from the discharge pipe 14 to the refrigeration cycle.
[0017]
The lubrication mechanism employs a differential pressure lubrication system, in which the refrigerating machine oil 15 at the lower part of the compressor is supplied to the main bearing 22 and the orbiting scroll bearing by a differential pressure between the pressure of the intermediate pressure chamber 12 and the discharge pressure in the closed container. 24, supply to sliding parts such as thrust surface 21. The intermediate pressure chamber 12 is controlled at an intermediate pressure between the suction pressure and the discharge pressure by an intermediate pressure hole (not shown) communicating with the compression chamber 6 formed on the base plate of the orbiting scroll 3. The refrigerating oil 15 is supplied to each sliding portion through the through hole 5b inside the crankshaft due to the pressure difference. The refrigerating machine oil that has entered the intermediate pressure chamber 12 is supplied to the compression chamber 6 from the intermediate pressure holes of the orbiting scroll 3 and the outer periphery of the base plate, and is discharged into the closed casing 1 together with the refrigerant gas from the discharge port 8.
[0018]
FIG. 3 is a detailed diagram illustrating only the check valve shown in FIGS. 1 and 2 in an enlarged manner. In FIG. 3, FIG. 3B is a view taken along the line bb in FIG. 3A, and FIG. 3C is a view taken along the line cc in FIG.
[0019]
The check valve includes a valve body (stopper surface) 18, a guide portion 19, and a support rod (connecting member) 20 for connecting the valve body and the guide portion. The guide portion 19 is reciprocally inserted and installed in the suction pipe 13 connected to the suction chamber 7 and is a ring-shaped member parallel to the flow direction of the refrigerant gas so as to hardly reduce the refrigerant gas passage area of the suction pipe. 19a and a rib 19b for coupling to the support rod 20. The outer diameter of the ring-shaped member 19a is adjusted so that the outer peripheral portion can move on the inner wall of the suction pipe.
[0020]
The valve element 18 is formed of a disc-shaped member, and closes the suction port of the suction chamber 7 so as to prevent the refrigerant gas and the refrigeration oil from the compression chamber from flowing back to the suction side when the operation of the compressor is stopped. Is completely shut off. In this embodiment, the end of the suction pipe 13 on the suction chamber side is inserted into the suction port of the suction chamber, and the valve body has a diameter larger than the inner diameter of the suction pipe end to close the suction pipe end. The valve element 18 is formed as thin as possible so as not to be a physical obstacle in the suction chamber, and a spring (coil) is pressed so that the lower part (bottom part) of the suction chamber is pressed by the flowing refrigerant gas pressure during operation of the compressor. The spring force of the spring 17 is adjusted.
[0021]
The support rod 20 is located substantially on the central axis of the check valve, and connects the valve element 18 and the guide portion 19. The length of the support rod 20 is determined so that the valve body 18 moves up and down in the suction chamber 7 and can be in close contact with both the bottom of the suction chamber and the suction port (end face of the suction pipe).
[0022]
Next, the operation of the check valve provided on the suction side of the scroll compressor will be described with reference to FIGS. FIG. 2 shows the operation of the check valve during compressor operation. The pressure of the refrigerant gas causes the valve element 18 of the check valve to compress the spring 17 provided below the guide portion 19 and suck the fixed scroll 2. It is pressed against the bottom of the chamber 7. As a result, the suction pipe side communicates with the compression chamber side, and the refrigerant gas is supplied to the compression chamber 6 and compressed.
[0023]
FIG. 4 shows the operation of the check valve when the compressor is stopped. When the operation of the compressor is stopped, the suction of the refrigerant gas is stopped, so that there is no gas pressure to push down the valve element 18, and the refrigerant gas being compressed in the compression chamber and the high-pressure refrigerant gas in the closed vessel 1 are going to flow backward. I do. As a result, the valve element 18 closes the lower end surface (suction port) of the suction pipe 13 due to the force for pushing the valve element 18 upward by the spring 17 and the gas pressure for the reverse flow, so that the refrigerant gas flows backward. Is prevented. Therefore, the refrigerating machine oil at the lower part of the compressor can be prevented from being taken out of the compressor from the suction pipe through the through-hole of the crankshaft, the bearing, and the like.
[0024]
As described above, the guide portion, which is a part of the check valve, and the spring (biasing means) for urging the guide portion upward are installed in the suction pipe, and only the thin valve body and the support rod for closing the suction port are provided. Since it is provided in the suction chamber, it does not become a physical obstacle in the suction chamber of the fixed scroll while maintaining the function of preventing the reversal of the orbiting scroll when the compressor is stopped and the function of preventing the refrigerating machine oil from being taken out of the compressor. The refrigerant gas suction passage area is hardly reduced, the pressure loss when the refrigerant gas is sucked into the compression chamber is reduced, and a decrease in the efficiency of the compressor can be prevented.
[0025]
【The invention's effect】
As described above, according to the present invention, a sufficient suction gas passage area for the refrigerant gas in the suction portion of the compressor can be ensured, so that the suction pressure loss can be reduced and the compressor efficiency can be improved.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an overall configuration of a scroll compressor according to an embodiment of the present invention.
FIG. 2 is an enlarged cross-sectional view of a main part around a check valve shown in FIG. 1, illustrating a state of the check valve during compressor operation.
FIG. 3 is an enlarged detailed view illustrating only the check valve shown in FIGS. 1 and 2;
FIG. 4 is an enlarged sectional view of a main part around the check valve shown in FIG. 1, illustrating a state of the check valve when the compressor is stopped.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Closed container, 2 ... Fixed scroll, 3 ... Orbiting scroll, 4 ... Frame, 5 ... Crankshaft, 6 ... Compression chamber, 7 ... Suction chamber, 8 ... Discharge port, 9 ... Stator, 10 ... Rotor, 11, ... Oldham ring, 12: intermediate pressure chamber, 13: suction pipe (suction pipe), 14: discharge pipe, 15: refrigerating machine oil, 17: spring (biasing means, coil spring, elastic member), 18: valve body (stopper surface) ), 19: guide portion, 19a: ring-shaped member, 19b: rib, 20: support rod (connection member).

Claims (8)

A compression mechanism section having a fixed scroll and an orbiting scroll, and engaging a spiral wrap formed upright on the base plate with each other to form a compression chamber; and using the orbiting scroll of the compression mechanism section as a crankshaft. And a frame including a bearing that supports the crankshaft, a rotation prevention mechanism that prevents the orbiting scroll from rotating with respect to the frame, and a sealed container that accommodates each of the above elements. A scroll compressor having a suction pipe connected to a suction chamber of the compression mechanism and supplying compressed gas to the suction chamber;
A check valve is provided for preventing the compressed gas in the compression mechanism from flowing back to the suction side through the suction pipe and flowing out, and the check valve is provided with:
A valve body provided so as to be able to close the suction port of the compression mechanism suction chamber, and provided in the suction chamber;
A guide portion connected to the valve body by a connecting member and provided reciprocally in the suction pipe;
And a biasing means provided in the suction pipe for biasing the guide portion so as to close the suction port of the suction chamber with the valve body. In Claim 1, the said connection member which connects the said valve body and the said guide part is a thin support rod, and the said urging means is a coil spring arrange | positioned so that the said support rod may be located in the center. Features scroll compressor. A compression mechanism section having a fixed scroll and an orbiting scroll, and engaging a spiral wrap formed upright on the base plate with each other to form a compression chamber; and using the orbiting scroll of the compression mechanism section as a crankshaft. An electric motor driven through a shaft, a frame having a bearing for rotatably supporting the crankshaft, a rotation preventing mechanism for causing the orbiting scroll to orbit while maintaining an angular positional relationship with the frame, and each of these elements And a scroll compressor having a suction pipe connected to a suction part of the compression mechanism part and supplying a compressed refrigerant gas to the suction part.
A check valve is provided to prevent the refrigerant gas and the refrigerating machine oil in the compression mechanism from flowing backward and flowing back to the suction pipe side, and the check valve is provided with a check valve,
A valve body provided reciprocally in the suction chamber of the compression mechanism so as to close the suction port,
A guide portion connected to the valve body by a support rod and provided so as to be able to reciprocate in the suction pipe;
An elastic member provided in the suction pipe, for urging the guide portion upstream so that the valve element closes a suction port of the suction chamber;
When the compressor is stopped, the check valve closes the suction port by the action of the elastic member, so that the compressed refrigerant gas flows backward to the suction side to reverse the orbiting scroll and to move the refrigerant gas and the refrigerating machine oil to the upstream side. Scroll compression wherein backflow is prevented, and a sufficient suction passage area is secured by moving the valve body to the bottom of the suction chamber by refrigerant gas sucked when the compressor is operated. Machine. 4. The scroll compressor according to claim 3, wherein the elastic member is a coil-shaped spring, and is arranged to urge the guide portion upward. 5. 5. The refrigerant gas flow according to claim 1, wherein the guide portion is reciprocally inserted and installed in a suction pipe connected to a suction chamber and hardly reduces a refrigerant gas passage area of the suction pipe. A scroll compressor comprising a ring member parallel to the direction and a rib for connecting to a support rod. The valve body according to any one of claims 1 to 5, wherein the valve body is formed of a thin disk-shaped member. A scroll compressor configured to be pressed against the bottom of a chamber. In claim 6, the suction pipe side end of the suction pipe is inserted into the suction port of the suction chamber, and the valve body is configured to close the suction pipe end face with a diameter larger than the suction pipe end face inner diameter. A scroll compressor, characterized in that: In any one of claims 2 to 7, the support rod is located substantially on the center axis of the check valve, and connects the valve body and the guide portion. A scroll compressor characterized in that it is determined so as to be able to contact both the bottom of the suction chamber and the suction port by reciprocating in the suction chamber.

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