CN102400915B - Vortex Compressor - Google Patents

Abstract

The present invention provides a scroll compressor. In the conventional scroll compressor, the top plate of the fixed scroll bears the force generated by the pressure in the closed space (compression chamber) formed by the two scrolls on the side of the scroll body. The opposite side of the roll receives the force generated by the pressure of the discharge pressure space, and is deformed into a downwardly convex shape by the resultant force. On the other hand, the orbiting scroll deforms into an upwardly convex shape according to the distribution of pressure acting on the back surface of the orbiting scroll. Due to this deformation, the addendums and dedendums at the centers of the wraps of the two scrolls may come into contact with each other, resulting in reduced performance due to increased sliding loss, and reduced reliability due to sintering or seizure on the sliding surfaces. An object of the present invention is to provide a scroll compressor with high reliability and high efficiency. In order to achieve the above object, the present invention provides a ceiling chamber on the top of the fixed scroll ceiling, and a communication path for communicating the ceiling chamber with the back pressure chamber.

Description

scroll compressor

technical field

The present invention relates to a refrigerant compressor for refrigeration and air conditioning, and a scroll compressor suitable as an air or other gas compressor, and more particularly, to an appropriate scroll compressor capable of achieving high performance and high reliability for various applications.

Background technique

The scroll compressor described in Patent Document 1 includes: a discharge pressure space in the center and a pressure (hereinafter referred to as "intermediate pressure") space between the suction pressure and the discharge pressure in the outer peripheral part as the space constituting the orbiting scroll. The space on the back side, and the discharge pressure and intermediate pressure act on the back of the orbiting scroll to press the orbiting scroll to the fixed scroll, so as to prevent the pressure in the closed space formed by the orbiting and fixed scrolls from causing the two scrolls to separate.

In addition, in the scroll compressor described in Patent Document 2, the fixed scroll top plate is covered with a cover, the space between the fixed scroll top plate and the cover communicates with the compression chamber, and the compressor is introduced into the space between the fixed scroll and the cover. Compress the gas on the way.

[Patent Document 1] Japanese Patent Laid-Open No. 2004-293531

[Patent Document 2] Japanese Patent Laid-Open No. 2003-028079

In the so-called high-pressure chamber type scroll compressor in which the discharge pressure is reached in the closed container during operation, the top plate of the fixed scroll receives pressure generated in the closed space (compression chamber) formed by the two scrolls on the side of the scroll body. force, and bear the force generated by the pressure of the ejection pressure space on the opposite side of the scroll body, and deform into a downward convex shape under the combined force of these forces. On the other hand, the orbiting scroll deforms into an upwardly convex shape due to the distribution of pressure acting on the back surface of the orbiting scroll. Due to this deformation, the addendums and dedendums at the center portions of the scroll bodies of the two scrolls come into contact, which may result in performance degradation due to increased sliding loss, or reliability may be reduced due to seizing or seizure on the sliding surfaces.

In addition, in order to prevent the above-mentioned degradation of performance and reliability, it is conceivable to preliminarily provide clearances between the addendums and dedendums of the wraps of the two scrolls in consideration of the deformation of the two scrolls during the operation of the scroll compressor. However, according to this configuration, in an operating state in which the deformation of both scrolls is small, compressed gas leaks from a gap provided in advance between the wraps of both scrolls, so it is difficult to prevent performance degradation over a wide operating range.

In addition, it is also conceivable to cover the fixed scroll top plate with a cover, and guide the compressed gas from the compression chamber to the space (ceiling chamber) between the fixed scroll top plate and the cover, so that the gas acting on the fixed scroll top plate The pressure on the side opposite to the scroll body is lower than the discharge pressure, and the force on the side opposite to the scroll body of the fixed scroll top plate is reduced, thereby reducing the deformation of the fixed scroll top plate. However, since the gas pressure in the compression chamber always fluctuates during the compression operation, when the compression chamber and the ceiling chamber directly communicate, the gas guided from the compression chamber to the ceiling chamber returns to the compression chamber through the communication path again. The re-expansion and re-compression of the compressed gas is caused by the gas entering and leaving the compression chamber and the roof chamber, resulting in performance degradation.

Contents of the invention

An object of the present invention is to provide a scroll compressor with high reliability and high efficiency.

In order to achieve the above object, the present invention provides a top plate chamber on the upper part of the fixed scroll top plate portion, and provides a communication passage connecting the top plate chamber and the back pressure chamber.

【Invention effect】

An object of the present invention is to provide a scroll compressor with high reliability and high efficiency.

Description of drawings

FIG. 1 is a longitudinal sectional view showing a scroll compressor of Embodiment 1. FIG.

FIG. 2 is an enlarged view showing a compression mechanism unit in Embodiment 1. FIG.

FIG. 3 is an enlarged view showing a compression mechanism unit in Embodiment 2. FIG.

Fig. 4 is a longitudinal sectional view showing a conventional scroll compressor.

Symbol Description

1 scroll compressor

2 Compression Mechanism Department

3 drive unit

4 motors

5 fixed scroll

5a fixed scroll outlet

5b fixed scroll top plate

5c fixed scroll scroll body

6 orbiting scroll

6a orbiting scroll scroll body

6b back pressure hole

6c vortex platen

6d back side of orbiting scroll

6e orbiting scroll bearing

7 suction pipe

8 cover

9 frames

10 Ohm connector

11 sliding bearing

12 axis of rotation

12a crank pin

12b spindle part

12c auxiliary bearing support part

13 sealing ring

16, 26 Rolling bearings

22 rotors

23 stator

24 frame

25 shell

28 fuel pump

30 airtight containers

31 ejection pipe

37 Oil storage department

39 suction port

40 oil supply hole

41 top cover

42～45 seals

46 ejection gas guide pipe

47 ejection flange

101 eject pressure space

102 orbiting scroll back pressure chamber

103 roof room

104 connecting holes

105 spout outlet fitting part

106 compression chamber

107 pair bearing department

108 motor upper space

109 frame fitting part

110 tube fitting part

111 fixed scroll through hole

112 frame through hole

Detailed ways

Hereinafter, several embodiments of the present invention will be described with reference to the drawings. The same code|symbol in the figure of each Example represents the same thing or a corresponding thing.

【Example 1】

A scroll compressor according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2 .

Fig. 1 is a longitudinal sectional view of a scroll compressor according to a first embodiment of the present invention, and Fig. 2 is an enlarged view of a compression mechanism part in Fig. 1 .

The scroll compressor 1 is configured by accommodating a compression mechanism unit 2 , a drive unit 3 , and a rotating shaft 12 in an airtight container 30 . In this embodiment, a vertical scroll compressor in which the compression mechanism part 2 is arranged above and the drive part 3 is arranged below is a so-called high-pressure chamber type compressor.

The compression mechanism unit 2 is configured with a fixed scroll 5 , an orbiting scroll 6 , and a frame 9 as basic components. The frame 9 is fixed to the airtight container 30 and constitutes a member in which the rolling bearing 16 is disposed. The fixed scroll 5 has a scroll body 5c, a top plate 5b, and a discharge 5a as basic components, and is fixed to the frame 9 by bolts. The scroll 5c (fixed scroll 5c) is vertically erected on one side of the top plate 5b. The orbiting scroll 6 is composed of a scroll body 6a, a base plate 6c, an orbiting scroll bearing portion 6e, and a back pressure hole 6b as basic components. The scroll body 6a (orbiting scroll body 6a) is erected on one side of the orbiting scroll platen 6c. The orbiting scroll bearing portion 6e is formed to protrude vertically on the other side (the side opposite to the scroll body) of the orbiting scroll base plate 6c. The orbiting scroll 6 is formed by processing each structural part from a casting made of cast iron or aluminum.

The compression chamber 106 configured by meshing the fixed scroll 5 and the orbiting scroll 6 performs a compression operation, and the compression operation reduces the volume of the compression chamber by the orbiting scroll 6 relative to the fixed scroll 5 . In this compression operation, along with the orbiting motion of the orbiting scroll 6, the working fluid is sucked into the compression chamber 106 through the suction pipe 7 and the suction port 39, and the sucked working fluid is discharged from the discharge port of the fixed scroll 5 through the compression stroke. 5 a is discharged into the airtight container 30 , and then is discharged from the airtight container 30 through the discharge pipe 31 . Thus, the space in the airtight container 30 is maintained at the discharge pressure. A high-pressure refrigerant such as R410A, which is environmentally friendly to the global environment, is used as the working fluid compressed by the compression mechanism.

The driving unit 3 that drives the orbiting scroll 6 to orbit is composed of the following basic elements, that is, the motor 4 composed of the stator 23 and the rotor 22, the rotating shaft 12, the oil supply pump 28, and the main part of the rotation preventing mechanism of the orbiting scroll 6, that is, the O. The connector 10, the frame 9, the rolling bearings 16, 26, the orbiting scroll bearing part 6e, and the sliding bearing 11 arranged on the orbiting scroll bearing part 6e.

The rotary shaft 12 is configured integrally with a main shaft portion 12b, a crank pin 12a, and a sub-bearing support portion 12c. The main shaft part 12b and the sub bearing support part 12c are formed on the same axis and constitute a main shaft part. Furthermore, an oil supply pump 28 is fitted to the lower end portion of the rotary shaft 12 . The rolling bearings 16 and 26 constitute a rotary shaft support portion that rotatably engages the main shaft portion 12 b of the rotary shaft 12 and the sub-bearing support portion 12 c. The orbiting scroll bearing portion 6e is provided on the orbiting scroll 6 in such a manner that the sliding bearing 11 is press-fitted into the inner diameter thereof, and the crank pin 12a of the rotating shaft 12 is engaged so as to be movable in the direction of the rotating shaft, that is, in the thrust direction. Rotate freely.

The rolling bearing 16 is arranged on the upper side of the electric motor 4 , and the rolling bearing 26 constituting the main part of the sub-bearing portion 107 is arranged on the lower side of the electric motor 4 . The rolling bearings 16 and 26 constitute bearings for a main shaft that support the main shaft on both sides of the motor 4 . In this embodiment, since the main shaft portion is supported by the rolling bearings 16, 26 on both sides of the motor 4, it is possible to suppress power loss of the main shaft bearing and prevent inclination of the main shaft portion of the rotating shaft.

The rolling bearing 26 constitutes a main part of the sub-bearing portion 107 . The casing 25 is fixed on the lower frame 24 by bolts, and the lower frame 24 is fixed on the airtight container 30 . The rolling bearing 26 is inserted into the housing 25 from above, and a housing cover 27 is further attached from above.

The oil supply pump 28 is a positive displacement pump installed at the lower end of the rotating shaft 12, and is arranged so that the lubricating oil accumulated in the oil storage part 37 is forced to pass through the oil supply hole 40 to the rolling bearing 26, the orbiting scroll bearing part 6e and then the rolling bearing 16. Supply and lubricate. In addition, the oil supplied to the oil supply hole 40 is also supplied to the sliding part of the orbiting scroll 6 and the fixed scroll 5 . The oil supply hole 40 is provided so as to penetrate longitudinally concentrically with respect to the axis of the rotary shaft 12 . A horizontal oil supply hole communicating with the lower oil supply hole is provided to supply oil to the rolling bearing 26 .

The Oldham connector 10 is arranged on the back surface of the base plate 6 c of the orbiting scroll 6 . One set of the two sets of orthogonal key portions formed on the Oldham connector 10 slides in the key groove as a receiving portion of the Oldham connector 10 formed on the frame 9, and the remaining set slides in the key groove formed on the swirling vortex. The disk scroll body 6a slides in the key groove on the back side. As a result, the orbiting scroll 6 orbits without autorotating with respect to the fixed scroll 5 in a plane perpendicular to the axial direction in which the scroll body 6 a is erected.

In the compression mechanism part 2, when the crank pin 12a is eccentrically rotated by the rotation of the rotating shaft 12 connected to the electric motor 4, the orbiting scroll 6 is prevented from rotating relative to the fixed scroll 5 by the rotation preventing mechanism of the Oldham joint 10. The orbiting motion is performed, and the gas is sucked into the compression chamber 106 formed by the scroll wraps 5 c and 6 a through the suction pipe 7 and the suction port 39 . Utilizing the orbiting motion of the orbiting scroll 6 , the volume of the compression chamber 106 is reduced while moving toward the center to compress the gas, and the compressed gas is ejected from the fixed scroll ejection port 5 a into the ejection pressure space 101 . The gas injected into the discharge pressure space 101 circulates around the compression mechanism unit 2 and the motor 4, and then is released from the discharge pipe to the outside of the compressor.

It should be noted that the back pressure hole 6b connecting the compression chamber 106 and the orbiting scroll back pressure chamber 102 at the back of the orbiting scroll is provided on the base plate 6c of the orbiting scroll 6, and the orbiting scroll back pressure chamber 102 The pressure is maintained at the middle pressure (intermediate pressure) between the suction pressure and the discharge pressure. The orbiting scroll back pressure chamber 102 formed on the back side of the orbiting scroll 6 is a space surrounded by the orbiting scroll 6 , the frame 9 , and the fixed scroll 5 .

The top plate chamber 103 of this embodiment is constituted by fixing the top plate cover 41 on the fixed scroll top plate portion 5b, that is, on the opposite side of the fixed scroll body with respect to the top plate portion, with bolts so that the fixed scroll discharge port 5a and the discharge pressure space 101 are not communicated with the ceiling chamber 103, and the discharge port fitting part 105 using the seal 42 is provided. The top plate chamber and the orbiting scroll back pressure chamber 102 are communicated through the communication hole 104 to introduce back pressure into the top plate chamber 103 .

Next, the operation of the scroll compressor 1 will be described. When the rotating shaft 12 is rotated by the motor 4, the orbiting scroll 6 orbits without rotating due to the rotating motion of the crank pin 12a of the rotating shaft 12 and the rotation prevention of the Oldham coupling 10. As a result, the space (compression chamber 106) formed by the two scroll wraps 5c, 6a of the orbiting scroll 6 and the fixed scroll 5 decreases its volume while moving toward the center, thereby compressing the air sucked in from the suction pipe 7. The gas is ejected from the fixed scroll outlet 5a. The gas of the ejected refrigerant and lubricating oil collides with the inner wall of the upper cover 8, and the separated lubricating oil flows to the oil reservoir 37 below the airtight container 30, and the gas passes through the passage formed on the frame 9 to cool the motor 4. , to be discharged out of the compressor through the discharge pipe 31 of the airtight container.

Here, a part of the gas whose volume is reduced in the compression chamber 106 and has an intermediate pressure is guided to the orbiting scroll back pressure chamber 102 through the back pressure hole 6b formed in the orbiting scroll base plate 6c. The orbiting scroll 6 is pressed against the fixed scroll 5 by the resultant force of the intermediate pressure acting on the back pressure chamber 102 of the orbiting scroll back portion 6 d and the discharge pressure acting on the inner side of the seal ring 13 . In addition, the orbiting scroll 6 bears the force of pulling the orbiting scroll 6 and the fixed scroll 5 apart under the pressure of the compression chamber 106. By setting the intermediate pressure so that the pressing force is greater than the pulling force, an appropriate force is applied to the orbiting scroll 6. The fixed scroll 5 presses the orbiting scroll 6 .

The fixed scroll 5 receives the downward force generated by the pressure of the top plate chamber 103 communicated with the orbiting scroll back pressure chamber 102 at the fixed scroll top plate portion 5b, and the compression chamber 106 composed of the fixed scroll 5 and the orbiting scroll 6 The upward force produced by the pressure.

In the conventional structure in which the top plate chamber 103 is not provided, the pressure of the ejection pressure space 101 acts on the fixed scroll top plate portion 5b. In the so-called high pressure ratio operation where the suction pressure is low and the discharge pressure is high, since the force generated by the pressure of the discharge pressure space 101 is too large compared with the force generated by the pressure of the compression chamber 106, in the existing structure , the fixed scroll top plate portion 5b is largely deformed in a downwardly convex shape.

In this embodiment, since the force generated by the pressure of the top plate chamber 103 is not too large relative to the force generated by the pressure of the compression chamber 106, deformation of the fixed scroll top plate portion 5b can be reduced even in high pressure ratio operation.

By reducing the deformation of the fixed scroll top plate portion 5b, the contact between the sliding parts of the two scroll wraps that occurs during the operation of the scroll compressor 1 is reduced, and performance degradation at high loads can be prevented, thereby preventing occurrence of sintering or stuck to ensure reliability. In addition, since the preset gap between the addendum or dedendum of the two scroll wraps is reduced or made zero, the leakage of gas compressed in the compression chamber can be reduced even at low load, thereby improving performance. .

The top plate chamber is communicated with the back pressure chamber to maintain the pressure of the top plate chamber. The reason for this is to reduce the re-expansion and re-compression of the refrigerant gas by relatively stabilizing the pressure in the back-pressure chamber. When the ceiling chamber and the compression chamber are communicated, since the pressure of the compression chamber changes, the entry and exit of refrigerant gas between the ceiling chamber and the compression chamber increases, resulting in performance degradation due to re-expansion and recompression.

According to this embodiment, performance can be improved over a wide operating range from low load to high load, and a highly reliable scroll compressor can be obtained even under high load.

In this embodiment, rolling bearings are used as the main shaft portion 12b and the sub-bearing support portion 12c of the rotary shaft 12, but one or both of the bearing support portions may be used as sliding bearings.

In this way, by disposing the top plate cover on the fixed scroll top plate portion, providing a top plate chamber between the top plate cover and the fixed scroll top plate portion, and providing a seal using a seal so that the top plate chamber and the fixed scroll discharge port do not communicate with each other. The fitting portion is provided, and the orbiting scroll back pressure chamber communicates with the top plate chamber, thereby providing a highly reliable and efficient scroll compressor.

[Example 2]

A scroll compressor according to a second embodiment of the present invention will be described using FIG. 3 .

Use the space between the fixed scroll top plate 5b and the upper cover 8 as the top plate chamber 103, use the discharge flange 47 to fit one end of the discharge gas guide pipe 46 into the fixed scroll discharge port 5a, and make the discharge gas guide pipe The other end of 46 is guided to the motor upper space 108 through the through holes 111 and 112 provided in the fixed scroll 5 and the frame 9 , so that the fixed scroll discharge port 5 a communicates with the motor upper space 108 . Here, the outer diameter of the frame 9 and the inner wall of the airtight container 30 and the discharge gas guide pipe 46 and the through-hole 112 of the frame 9 are fitted with the sealing members 43 and 45 so that the ceiling chamber 103 does not communicate with the upper space 108 of the motor. combine. Furthermore, the orbiting scroll back pressure chamber 102 and the top plate chamber 103 are configured to communicate with each other.

According to this structure, the space between the fixed scroll top plate portion 5b and the upper cover 8 is formed as a whole as the top plate chamber 103, and the pressure of the top plate chamber 103 acts on the whole of the side opposite to the scroll body of the fixed scroll 5. Also, deformation of the fixed scroll top plate portion 5b can be reduced.

As described above, according to the structure disclosed in each of the above-mentioned embodiments, the intermediate pressure acts on the side opposite to the scroll body of the fixed scroll top plate portion, reducing the load on the fixed scroll top plate portion from the opposite scroll body side and the scroll body side. The resultant force of the force can reduce the deformation of the top plate of the fixed scroll.

By reducing the deformation of the fixed scroll, the contact between the scroll body sliding parts of the two scrolls can be reduced, and in the so-called high pressure ratio operation where the suction pressure is low and the discharge pressure is high, performance degradation can be prevented, and sintering can be prevented more reliably. or get stuck.

In addition, since the preset gap between the addendum and dedendum of the two scroll wraps can be reduced or made zero, the leakage of gas compressed in the compression chamber can be reduced even at low load, thereby enabling Improve performance. Therefore, it is possible to provide a scroll compressor having high reliability even at high loads in addition to improving performance over a wide operating range.

Furthermore, the pressure in the back chamber of the orbiting scroll does not fluctuate during the compression operation, and is a substantially constant pressure. Since the top chamber communicates with the orbiting scroll back chamber, the pressure in the top chamber is kept constant during the compression operation, so that the gas in the top chamber and the orbiting scroll back pressure chamber does not return to the compression chamber. Therefore, the gas guided from the compression chamber to the back chamber of the orbiting scroll and the ceiling chamber does not return to the compression chamber, and re-expansion and re-compression of the compressed gas do not occur. Therefore, there is no fear of performance degradation due to this embodiment.

Claims (3)

1. A scroll compressor, which utilizes a fixed scroll body erected on the top plate of the fixed scroll and an orbiting scroll body erected on the mirror plate of the orbiting scroll to form a compression chamber, and by making the The fixed scroll and the orbiting scroll relatively rotate to compress the high-pressure chamber type scroll compressor of the refrigerant, which is characterized in that, The scroll compressor has: a back pressure chamber formed on the back side of the orbiting scroll and maintained at a pressure intermediate between a suction pressure and a discharge pressure; a top plate chamber disposed on an opposite side of the fixed scroll with respect to the top plate of the fixed scroll; A communication path communicates the top plate chamber with the back pressure chamber. 2. A scroll compressor, comprising: a compression mechanism part having a fixed scroll, an orbiting scroll, and a frame; a drive part for driving the compression mechanism part, and the compression mechanism part and the drive part are accommodated in an airtight container; In the container, a back pressure chamber is provided on the back side of the orbiting scroll, and the refrigerant gas pressure passing through the back pressure chamber presses the orbiting scroll against the fixed scroll, and the scroll compressor characterized in that, A top plate cover is disposed on the top plate portion of the fixed scroll, and a top plate chamber is provided between the top plate cover and the top plate portion of the fixed scroll so that the top plate chamber and the discharge port of the fixed scroll A non-communicating system is provided with a fitting portion using a seal, the back pressure chamber is maintained at an intermediate pressure between the suction pressure and the discharge pressure, and the back pressure chamber communicates with the top plate chamber. 3. A scroll compressor, comprising: a compression mechanism part having a fixed scroll, an orbiting scroll, and a frame; a drive part for driving the compression mechanism part, and the compression mechanism part and the drive part are accommodated in an airtight container; In the container, a back pressure chamber is provided on the back side of the orbiting scroll, and the refrigerant gas pressure passing through the back pressure chamber presses the orbiting scroll against the fixed scroll, and the scroll compressor characterized in that, One end of the discharge gas guide pipe communicates with the discharge port of the fixed scroll, and the other end of the discharge gas guide pipe communicates with the upper space of the motor through through holes provided on the fixed scroll and the frame. , so that the discharge port of the fixed scroll communicates with the upper space of the motor, The space between the top plate portion of the fixed scroll and the upper cover is used as a top plate chamber, and the outer diameter of the frame and the inner wall of the airtight container are fitted with seals, and the ejection gas guide pipe is fitted with the inner wall of the airtight container. the through hole of the frame so that the top plate chamber is not communicated with the upper space of the motor, The back pressure chamber is maintained at an intermediate pressure between the suction pressure and the discharge pressure, and the back pressure chamber communicates with the top plate chamber.