JPH0979152A - Scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of part items and production cost, and improve processability and assembling workability by simplifying the constitution of a power saving mechanism of a scroll compressor. SOLUTION: A saving hole 51 to release a refrigerant in a compression space to the low pressure side is formed in a fixed scroll 43, and bellows 55 to open and close the saving hole 51 by extending and contracting by pressure applied to the inside and a back pressure passage 57 to apply pressure in this bellows 55, are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor that engages a fixed scroll and an orbiting scroll to perform compression.

[0002]

2. Description of the Related Art A conventional scroll compressor is disclosed, for example, in Japanese Patent Laid-Open No. 1214881 (F04C18 / 02). Next, the conventional structure shown in this publication is shown in FIG.
This will be described with reference to FIG. In FIG. 5, the compressor 61 includes a closed container 7, a scroll element compression 8 housed in the upper side of the container, and an electric element 9 housed in the lower side. Reference numeral 10 denotes a frame, and a bearing 12 for supporting a rotating shaft 11 is provided in the center of the frame.

The scroll compression element 8 is a fixed scroll 1.
3 and the orbiting scroll 14. The fixed scroll 13 is brought into pressure contact with the inner wall of the closed container 7 to partition the interior of the container into a high pressure chamber 15 and a low pressure chamber 16 which are disk-shaped end plates 17.
And an annular wall 18 protruding from the peripheral edge of one surface of the end plate.
And a spiral wrap 19 which is surrounded by the annular wall and is erected on the end plate 17 and which is involute or has a curved line approximate to this. The fixed scroll 13 has the annular wall 18 and the wrap 19 protruding downward.

The orbiting scroll 14 is a disk-shaped end plate 20.
And a spiral wrap 21 standing on one surface of the end plate 20 and formed of an involute shape or a curve approximate to this, and a pin 2 protruding in the center of the other surface of the end plate 20.
And 2. Then, the orbiting scroll 14 is configured such that the wrap 21 faces the wrap 19 of the fixed scroll 13 and engages with the wrap 21 in the upward direction, and a plurality of compression spaces 23 are formed therein. The compression space 23 gradually shrinks from the outside to the inside to compress the refrigerant.

Further, the end plate 17 of the fixed scroll 13 is provided with a discharge hole 24 at the center which communicates with the compression space 23.

Reference numeral 25 denotes a boss hole which is provided at the tip of the rotary shaft 11 and into which the pin 22 of the orbiting scroll 14 is inserted. The center of the boss hole is provided eccentrically with the axis of the rotary shaft 11. Reference numeral 26 is a joint means for revolving the orbiting scroll 14 with respect to the fixed scroll 13 on the circular orbit so as not to rotate. A suction passage 27 that guides the refrigerant to the scroll compression element 8 is provided on the outer periphery of the frame 10. Reference numeral 28 denotes a suction pipe attached to the closed container 7, and the suction pipe 28 communicates with the low pressure chamber 16 in the closed container 7 below the electric element 9. 29 is a discharge pipe attached to the upper part of the closed container 7,
The discharge pipe 29 communicates with the high pressure chamber 15 in the closed container 7.

The end plate 17 of the fixed scroll 13 is provided with a power save hole 30 for allowing the refrigerant in the compression space 23 to escape to the low pressure chamber. This power save hole is formed by pairing two holes. The power save hole 30 is formed by a first hole 31 communicating with the compression space 23 and a second hole 32 communicating with the low pressure chamber 16. The first and second holes 31 and 32 are formed so as to be inclined so that the openings on the surface opposite to the wrap 19 are close to each other.

Reference numeral 34 denotes a cover provided on the surface of the end plate 17 of the fixed scroll 13 on the side opposite to the wrap, and this cover has a recess 36 for accommodating a valve 35 for opening and closing the first hole 31 and the second hole 32, and The lead-out hole 37 is formed by cutting.
The valve 35 is always biased by a spring in the direction of being pushed up. The outlet hole 37 is connected to the high pressure guide pipe 5 communicating with the high pressure side of the refrigerant circuit, and the discharge hole 24 is opened and closed by the discharge valve 40.

During full-load operation, a solenoid valve (not shown) is opened to guide the high-pressure refrigerant from the high-pressure guide tube 5 into the recess 36 through the outlet hole 37 to press the valve 35 toward the fixed scroll 13 side. The communication between the hole 31 and the second hole 32 is blocked, and the refrigerant flowing into the compression space 23 is cooled by the low pressure chamber 16
I try not to go back to.

On the other hand, at the time of light load operation, the solenoid valve is closed to prevent high-pressure refrigerant from being introduced from the high-pressure guide tube 5 into the recess 36 through the outlet hole 37. As a result, the spring pushes up the valve 35, so that the compression space 2
The refrigerant flowing into the valve 3 flows into the first hole 31 and the valve 3
5 was further pushed up, flowed from the recess 36 through the second hole 32, and leaked from the second hole 32 to the low pressure chamber 16, so that the refrigerating capacity became a capacity commensurate with the load.

[0011]

However, in such a power save mechanism, the high-pressure refrigerant guided from the high-pressure guide tube 5 to the concave portion 36 is the first from the contact surface (sliding surface) between the valve 35 and the inner wall of the concave portion 36. In order to prevent the valve 35 from leaking into the hole 31 and the second hole 32 and prevent the valve 35 from being caught on the inner wall of the recess 36 and causing malfunction.
The clearance between the valve 35 and the recess 36 must be strictly adjusted, which increases the processing cost.

Further, the high-pressure refrigerant is guided from the high-pressure guide tube 5 into the recess 36 through the outlet hole 37 to press the valve 35 toward the fixed scroll 13 side, whereby the first hole 31 and the second hole 32 are formed. Since it has a structure for blocking the communication between the first hole 31 and the second hole 32, the degree of freedom in the positions of the first hole 31 and the second hole 32 is small.

Further, as described above, when the valve 35 is pushed up, an auxiliary component such as a spring is required, so that there is a problem that the processing becomes difficult and the cost further rises.

The present invention has been made to solve the above-mentioned conventional technical problems, and simplifies the structure of the power save mechanism to reduce the number of parts and the production cost.
Another object of the present invention is to provide a scroll compressor that can improve workability and assembly workability.

[0015]

According to another aspect of the present invention, there is provided a scroll compressor in which a hermetically sealed container houses an electric element having a rotary shaft and a scroll compression element driven by the electric element. The elements are a frame that has a bearing for the rotating shaft in the center, a fixed scroll with a spiral wrap standing on the end plate, and an orbiting scroll with a spiral wrap standing on the end plate that engages with the fixed scroll. Drive means for orbiting the orbiting scroll with respect to the fixed scroll so that the plurality of compression spaces formed by the orbiting scroll and the fixed scroll are gradually reduced from the outside to the inside to perform compression. The fixed scroll is provided with a joint means for revolving the fixed scroll so as not to rotate with respect to the fixed scroll. The fixed scroll has a discharge hole that discharges the refrigerant into the closed container.The fixed scroll has a power save passage for letting the refrigerant in the compression space escape to the low pressure side, and the fixed scroll expands and contracts according to the pressure applied to the power The bellows for opening and closing the save passage and the back pressure passage for applying pressure to the bellows are provided.

A scroll compressor according to a second aspect of the present invention houses an electric element having a rotating shaft in a closed container and a scroll compressing element driven by the electric element, the scroll compressing element being the rotating shaft. A frame having a bearing in the center, a fixed scroll with a spiral wrap standing on the end plate, and an orbiting scroll with a spiral wrap standing on the end plate that engages with the fixed scroll. Driving means for orbiting the orbiting scroll with respect to the fixed scroll so as to perform compression by gradually reducing a plurality of compression spaces formed by the scroll and the fixed scroll from the outside to the inside, and the orbiting scroll. And a coupling means for revolving the fixed scroll so as not to rotate about the fixed scroll, and the fixed scroll is filled with a refrigerant compressed in a compression space. A discharge hole for discharging in the container is provided, and the save hole and the return hole formed in the fixed scroll in communication with the compression space and the low-pressure side of the closed container, and the wrap of the end plate of the fixed scroll A communication passage formed on the opposite side and connecting the save hole and the return hole,
The bellows, which is located in the communication passage, opens and closes the save hole by expanding and contracting due to the pressure applied to the inside, and a back pressure passage for applying pressure to the bellows.

Further, a scroll compressor according to a third aspect of the present invention houses an electric element having a rotating shaft in a closed container, and a scroll compressing element driven by the electric element, and the scroll compressing element has the rotating shaft. A frame having a bearing in the center, a fixed scroll with a spiral wrap standing on the end plate, and an orbiting scroll with a spiral wrap standing on the end plate that engages with the fixed scroll. Driving means for orbiting the orbiting scroll with respect to the fixed scroll so as to perform compression by gradually reducing a plurality of compression spaces formed by the scroll and the fixed scroll from the outside to the inside, and the orbiting scroll. And a coupling means for revolving the fixed scroll so as not to rotate about the fixed scroll, and the fixed scroll is filled with a refrigerant compressed in a compression space. A discharge hole for discharging in the container is provided, and the save hole and the return hole formed in the fixed scroll in communication with the compression space and the low-pressure side of the closed container, and the wrap of the end plate of the fixed scroll It is composed of a cover attached on the opposite side, and this cover is located in the communication passage that connects the save hole and the return hole, and the bellows that expands and contracts by the pressure applied inside to open and close the save hole. And a back pressure passage for applying pressure inside the bellows.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a refrigerant circuit diagram of a refrigeration cycle using the scroll compressor 1 of the present invention, FIG. 2 is a vertical sectional side view of the scroll compressor 1 of the present invention, and FIG. 3 is a scroll compression element of the scroll compressor 1 of the present invention. FIG. 4 is an enlarged vertical side view, and FIG. 4 is another enlarged vertical side view of the scroll compression element of the scroll compressor 1 of the present invention.

In each figure, the same symbols as those in FIG. 5 have the same or the same functions.

In the refrigerant circuit of FIG. 1, 1 is a scroll compressor of the present invention, 2 is a condenser, 3 is a pressure reducing device, and 4 is an evaporator, and these are connected by piping to form a refrigeration cycle. Reference numeral 58 denotes a back pressure guide pipe provided on the inlet side of the condenser 2 and the outlet side of the evaporator 4 and the compressor 1.
And a pipe 58B communicating with the outlet side of the evaporator 4 join together and are connected to the compressor 1. The pipes 58A and 58B are connected to the solenoid valves 39A and 58B, respectively. 39B is provided.

The compressor 1 comprises a closed container 7, a scroll compression element 68 housed in the upper part of the container 7, and an electric element 9 housed in the lower part. Reference numeral 10 denotes a frame, and a bearing 12 for supporting a rotating shaft 11 is provided at the center of the frame 10. Scroll compression element 68
Is composed of a fixed scroll 43 and an orbiting scroll 14. The fixed scroll 43 is pressed against the inner wall of the closed container 7 to partition the inside of the container into a high pressure chamber 15 and a low pressure chamber 16, and a disk-shaped mirror plate 47, and an annular wall 48 protruding from one end of the mirror plate 47. And an involute wrap 49 which is surrounded by the annular wall 48 and is erected on the end plate 47, or a spiral wrap 49 having a curved line similar to this. The fixed scroll 43 has the annular wall 48 and the wrap 49 protruding downward.

The orbiting scroll 14 is a disk-shaped end plate 20.
And a spiral wrap 21 standing on one surface of the end plate 20 and formed of an involute shape or a curve approximate to this, and a pin 2 protruding in the center of the other surface of the end plate 20.
And 2. Further, the orbiting scroll 14 is configured such that the wrap 21 faces the lap 49 of the fixed scroll 43 so as to be engaged with the wrap 21 with the protruding direction upward, and a plurality of compression spaces 23 are formed inside. The compression space 23 gradually shrinks from the outside to the inside to compress the refrigerant.

The end plate 47 of the fixed scroll 43 is provided with a discharge hole 24 at the center which communicates with the compression space 23.
The discharge hole 24 is opened and closed by a discharge valve 40.

A boss hole 25 is provided at the tip of the rotary shaft 11 and into which the pin 22 of the orbiting scroll 14 is inserted. The center of the boss hole 25 is eccentric to the axis of the rotary shaft 11. Reference numeral 26 is a joint means for revolving the orbiting scroll 14 with respect to the fixed scroll 13 on the circular orbit so as not to rotate. A suction passage 27 that guides the refrigerant to the scroll compression element 68 is provided on the outer periphery of the frame 10. 28
Is a suction pipe attached to the closed container 7, and the suction pipe 28
Communicates with the low pressure chamber 16 in the closed container 7 below the electric element 9. 29 is a discharge pipe attached to the upper part of the closed container 7, and this discharge pipe communicates with the high pressure chamber 15 in the closed container 7.

The end plate 47 of the fixed scroll 43 is provided with a power save hole 50 which constitutes a power save passage for allowing the refrigerant in the compression space 23 to escape to the low pressure chamber 16. This power save hole 50 is a save hole 5 communicating with the compression space 23.
1 and a return hole 52 communicating with the low pressure chamber 16.

Reference numeral 54 denotes a cover attached to the surface of the end plate 47 of the fixed scroll 43 on the side opposite to the wrap side.
On the lower surface of 4, there is formed a communication passage 56 that connects the upper ends of the save hole 51 and the return hole 52. This communication path 56
At the position corresponding to above the save hole 51 in the bellows 5,
5 is attached. The bellows 55 is made of a thin metal plate, has a flat lower surface, and has a bellows-shaped periphery, and expands and contracts by the pressure applied inside to open and close the save hole 51.

In the cover 54, the back pressure guide tube 5 is provided.
8 is formed with a back pressure passage 57, and the insides of the bellows 55, 55 are communicated with the back pressure passage 57 at the upper end and sealed. The back pressure passage 57 applies back pressure to the bellows 55. The solenoid valve 39A is opened during full load operation and the solenoid valve 39B is closed to apply high pressure to the bellows 55, and the solenoid valve 39A is operated during light load operation.
Is closed and the solenoid valve 39B is opened to apply a low pressure to the bellows 55.

The scroll compressor 1 configured as described above
At, when the electric element 9 is rotated, the rotational force is transmitted to the orbiting scroll 14 via the rotary shaft 11. That is, the orbiting scroll 14 has the boss hole 25 of the rotary shaft 11.
The pin 22 that is inserted eccentrically with respect to the axis of this rotating shaft.
The joint means 26 revolves around a circular orbit so as not to rotate with respect to the fixed scroll 43.

The fixed scroll 43 and the orbiting scroll 14 gradually reduce the compression space 23 formed by these scrolls from the outside to the inside, and from the suction pipe 28 to the low pressure chamber 16 in the closed container 7. To compress the refrigerant flowing into the suction passage 27 on the outer periphery of the frame 10 through the electric element 9.

This compressed refrigerant is the fixed scroll 43.
The discharge valve 40 is opened from the discharge hole 24 to be discharged into the high pressure chamber 15, and is discharged from the discharge pipe 29 to the outside of the closed container 7 to be condensed and liquefied in the condenser 2. This liquid refrigerant is decompressed by the decompression device 3 and vaporized in the evaporator 4 to perform a cooling action.
Return to.

During full load operation, the solenoid valve 39A is opened and the solenoid valve 39B is closed as described above, and the high pressure refrigerant before flowing into the condenser 2 is passed from the back pressure guide pipe 58 to the back pressure passage 57.
The bellows 55 is extended through the above to extend the bellows 55 and press the bottom surface thereof toward the fixed scroll 43 to close the save hole 51. This prevents the refrigerant flowing into the compression space 23 from returning to the low pressure chamber 16 (FIG. 3).

During light load operation, the solenoid valve 39A is closed and the solenoid valve 39B is opened so that the low pressure on the outlet side of the evaporator 4 is added to the bellows 55. As a result, the bellows 55 contracts and its bottom surface rises, and the save hole 51
The refrigerant flowing into the compression space 23 exits from the save hole 51, passes through the communication passage 56, and leaks from the return hole 52 to the low-pressure chamber 16, so that the refrigerating capacity becomes a capacity commensurate with the load (Fig. 4).

[0033]

As described above in detail, according to the invention of claim 1, a bellows which expands and contracts due to the pressure applied to the inside thereof in order to open and close the power save passage for releasing the refrigerant in the compression space to the low pressure side. Since it is used, it is not necessary to strictly control the processing accuracy as in the case of using the conventional valve, and the workability is improved. Further, since it is not necessary to attach auxiliary parts such as springs as in the conventional case, the number of parts and the production cost can be reduced.

According to the invention of claim 2, in addition to the above, a save hole and a return hole formed in the fixed scroll in communication with the compression space and the low-pressure side of the closed container, respectively.
By the communication passage that is formed on the side opposite to the wrap of the end plate of the fixed scroll and that communicates these save hole and return hole, the refrigerant in the compression space is allowed to escape to the low pressure side, so the structure is simplified, The degree of freedom in design increases.

Further, according to the invention of claim 3, in addition to the above, in the cover attached to the side of the fixed scroll opposite the wrap of the end plate, a communication passage for communicating the save hole and the return hole and a save hole are provided. Since the bellows to be opened and closed and the back pressure passage for applying back pressure to the bellows are provided, the assembling workability is further improved.

[Brief description of drawings]

FIG. 1 is a refrigerant circuit diagram of a refrigeration cycle to which a scroll compressor of the present invention is applied.

FIG. 2 is a vertical cross-sectional side view of the scroll compressor of the present invention.

FIG. 3 is an enlarged vertical side view of a scroll compression element of the scroll compressor of the present invention.

FIG. 4 is another enlarged vertical side view of the scroll compression element of the scroll compressor of the present invention.

FIG. 5 is a vertical sectional side view of a conventional scroll compressor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 2 Condenser 3 Decompressor 4 Evaporator 7 Airtight container 9 Electric element 10 Frame 11 Rotating shaft 12 Bearing 14 Oscillating scroll 15 High pressure chamber 16 Low pressure chamber 20, 47 End plate 21, 49 Wrap 22 pin 23 Compression space 24 Discharge Hole 25 Boss hole 26 Coupling means 27 Suction path 28 Suction pipe 29 Discharge pipe 39A, 39B Solenoid valve 43 Fixed scroll 50 Power save hole 51 Save hole 52 Return hole 54 Cover 55 Bellows 56 Communication passage 57 Back pressure passage 58 Back pressure guide pipe

Claims (3)

[Claims] 1. An electric element having a rotary shaft and a scroll compression element driven by the electric element are housed in a closed container, and the scroll compression element includes a frame having a bearing of the rotary shaft in the center and an end plate. A fixed scroll in which a spiral wrap is erected, a swing scroll in which a spiral wrap is erected on an end plate that faces and faces the fixed scroll, and a plurality of swing scrolls and a fixed scroll are formed. Drive means for orbiting the orbiting scroll with respect to the fixed scroll so as to perform compression by gradually reducing the compression space from the outside to the inside, and revolving the orbiting scroll so as not to rotate with respect to the fixed scroll. And a discharge hole for discharging the refrigerant compressed in the compression space into the closed container in the fixed scroll. In the cooling compressor, the fixed scroll includes a power save passage for letting the refrigerant in the compression space escape to the low pressure side, a bellows that expands and contracts by the pressure applied inside to open and close the power save passage, and the bellows. A scroll compressor having a back pressure passage for applying pressure therein. 2. An electric element having a rotary shaft and a scroll compression element driven by the electric element are housed in a closed container, and the scroll compression element includes a frame having a bearing of the rotary shaft in the center and an end plate. A fixed scroll in which a spiral wrap is erected, a swing scroll in which a spiral wrap is erected on an end plate that faces the fixed scroll and engages with each other, and a plurality of swing scrolls and a fixed scroll are formed. Drive means for orbiting the orbiting scroll with respect to the fixed scroll so as to perform compression by gradually reducing the compression space from the outside to the inside, and revolving the orbiting scroll so as not to rotate with respect to the fixed scroll. And a discharge means for discharging the refrigerant compressed in the compression space into the closed container in the fixed scroll. In a compressor, a save hole and a return hole, which are formed in the fixed scroll and communicate with the compression space and the low-pressure side of the closed container, respectively, and the wrap of the end plate of the fixed scroll are formed on the opposite side, A communication passage that connects the save hole and the return hole,
A scroll compressor, characterized in that it comprises a bellows located in the communication passage, which expands and contracts by the pressure applied to the inside to open and close the save hole, and a back pressure passage for applying pressure to the bellows. . 3. An electric element having a rotary shaft and a scroll compression element driven by the electric element are housed in a hermetic container, and the scroll compression element includes a frame having a bearing for the rotary shaft in the center and an end plate. A fixed scroll in which a spiral wrap is erected, a swing scroll in which a spiral wrap is erected on an end plate that faces the fixed scroll and engages with each other, and a plurality of swing scrolls and a fixed scroll are formed. Drive means for orbiting the orbiting scroll with respect to the fixed scroll so as to perform compression by gradually reducing the compression space from the outside to the inside, and revolving the orbiting scroll so as not to rotate with respect to the fixed scroll. And a discharge means for discharging the refrigerant compressed in the compression space into the closed container in the fixed scroll. In a compressor, a save hole and a return hole, which are formed in the fixed scroll and communicate with the compression space and the low-pressure side of the closed container, respectively, and a cover attached to the opposite side of the fixed scroll end plate wrap. The cover includes: a communication passage that communicates the save hole and the return hole; a bellows that is located in the communication passage and that expands and contracts by the pressure applied to the inside to open and close the save hole; A scroll compressor having a back pressure passage for applying pressure therein.