JPH08319960A - Scroll compressor - Google Patents

Abstract

PURPOSE: To reliably prevent the generation of leak of refrigerant gas in the middle of compression by a scroll compression element during operation and to improve compression performance. CONSTITUTION: A scroll compression element 20 driven by a motor-driven element 10 contained in a closed container 1 comprises a fixed scroll 21 fixed at a main frame 5; a revolving scroll 31 slidably coupled to a thrust receiving part 51, formed at the main frame in such a manner that it is not rotated but revolved based on the fixed scroll, through an Oldham's coupling 6. Helical laps 23 and 33 formed facing the end plates 22 and 32, respectively, of the two scrolls are engaged with each other to form a compression chamber P comprising a plurality of compression spaces. A thrust bearing member 36 fitted in the drive shaft 13 of a motor-driven element is differently formed at the bearing part 34 of the revolving scroll 34. A back pressure space 8 is formed between the thrust bearing member and the back of the end plate of the revolving scroll and a back pressure passage 9 communicated with the compression chamber is formed in the back pressure space 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor mounted in, for example, an air conditioner or a refrigerator, and more particularly, by reducing the occurrence of refrigerant gas leakage during compression by a scroll compression element during operation. It is intended to improve performance characteristics such as volume efficiency and compression efficiency.

[0002]

2. Description of the Related Art Conventionally, in this type of scroll compressor, a scroll compression element driven by an electric element is formed of a fixed scroll and an orbiting scroll, and the scroll end plates of these scrolls are provided symmetrically to each other. The spiral wraps are engaged with each other to form a compression chamber consisting of a plurality of compression spaces, and the eccentric movement of the orbiting scroll in the thrust direction causes the refrigerant gas to be supplied to the low pressure chamber side in the closed container. The pressure is gradually reduced from the low pressure side outside the compression chamber toward the high pressure side inside, and compressed to be discharged to the high pressure chamber side.

[0003]

However, in such a scroll compressor having the conventional structure, the pressure of the refrigerant gas during compression during operation causes a force in the direction in which the orbiting scroll separates from the fixed scroll. In response to this, a gap is created between the sliding surface of the wrap tip of the orbiting scroll and the end plate of the fixed scroll, and refrigerant gas leaks during compression from this gap, resulting in performance characteristics such as volume efficiency and compression efficiency. There was a problem of lowering.

An object of the present invention is to provide a scroll compressor capable of reducing leakage of refrigerant gas during compression by a scroll compression element and improving performance characteristics such as volume efficiency and compression efficiency. To do.

[0005]

In order to solve the above problems, the present invention comprises an electric element and a scroll compression element which are housed in a closed container, and the scroll compression element is fixed to a main frame. Fixed scroll,
An orbiting scroll slidably connected to a thrust receiving portion formed on the main frame so as to revolve with respect to the fixed scroll through an Oldham coupling so that the fixed scroll and the orbiting scroll end plate. The spiral-shaped wraps formed so as to face each other are meshed with each other to form a compression chamber composed of a plurality of compression spaces, while the drive shaft of the electric element is formed on the back surface of the end plate of the orbiting scroll. The refrigerant gas supplied to the low pressure chamber side in the closed container by the eccentric motion in the thrust direction is gradually contracted from the low pressure side outside the compression chamber toward the high pressure side inside and compressed. In a scroll compressor configured to discharge to the high pressure chamber side in the closed container, the drive shaft of the electric element is fitted to the bearing portion of the orbiting scroll. A thrust bearing member is provided separately, and a back pressure space is formed between the thrust bearing member and the back surface of the end plate of the orbiting scroll, and a back pressure passage communicating with the compression chamber is provided in the back pressure space. It is configured as follows.

In this case, the Oldham coupling mounting portion is provided on the orbiting scroll side connected to the main frame.

[0007]

That is, according to the present invention, by adopting the above structure, a thrust bearing member to which the drive shaft of the electric element fits is separately provided in the bearing portion of the orbiting scroll, and the thrust bearing member and the orbiting scroll are provided. A back pressure space is formed between the back surface of the end plate and the back surface of the end plate, and a back pressure passage communicating with the compression chamber is provided in the back pressure space. It is possible to apply a back pressure to the end plate of the orbiting scroll at all times, whereby the wrap tip of the orbiting scroll is constantly pressed against the end plate of the fixed scroll, preventing the occurrence of a gap as before, The occurrence of refrigerant gas leakage during compression is reduced.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the invention will be described in detail below with reference to the drawings. FIG. 1 shows a scroll compressor according to the invention. In FIG. Is formed of a cylindrical case 2 and upper and lower end caps 3 and 4 capped on both upper and lower end portions of the case 2.

A main frame 5 is fixed to the upper part of the closed container 1, an electric element 10 is provided on the lower side of the main frame 5 on the side of the low pressure chamber 1A, and an electric element 10 is provided on the upper part thereof. Driven scroll compression elements 20 are each housed.

The electric element 10 comprises a stator 11, a rotor 12 which is rotatably fitted in the stator 11, and a drive shaft 13 which forms a central shaft portion of the rotor 12. The scroll compression element 20 is a fixed scroll 2 fixed to the main frame 5 via bolts or the like.
1 and the orbiting scroll 31 slidably supported by the thrust receiving portion 51 formed on the upper surface of the main frame 5, and the spiral wrap 23 formed on the lower surface of the end plate 22 of the fixed scroll 21 Orbiting scroll 3
The spirally wrapped wrap 33 formed on the upper surface of the first end plate 32 is meshed with each other to form the compression chamber P including a plurality of compression spaces.

The orbiting scroll 31 has its end plate 32.
The main frame 5 through the Oldham's joint 6 attached to the attachment portion 34 formed of a groove or a protrusion formed on the
And a bearing portion 35 is formed in the center of the back surface of the end plate 32, and a thrust bearing member 36 is provided separately in this bearing portion 35. The bearing member 36 has a structure in which the eccentric shaft portion 14 of the drive shaft 13 of the electric element 10 is fitted into a boss portion 37 formed in the center of the lower surface of the bearing member 36.

Then, the end plate 3 of the orbiting scroll 31.
The back pressure space 8 sealed by the sealing member 7 is formed between the bearing portion 35 formed on the back surface of the second bearing 2 and the thrust bearing member 36 fitted into the bearing portion 35. 8 communicates with the compression chamber P via a back pressure passage 9.

That is, the scroll compression element 20.
Is a fixed scroll 21 driven by the electric element 10.
Orbiting scroll 31
Is eccentrically moved in the thrust direction, and the compression chamber P is gradually contracted from the outer low-pressure side compression space toward the inner high-pressure side compression space, and thus is supplied from the low-pressure chamber 1A side in the closed container 1. The refrigerant gas is compressed, and the compressed refrigerant gas is discharged from the discharge port 24 communicating with the high pressure side of the compression chamber P formed in the central portion of the fixed scroll 21, and the cover provided on the upper surface of the fixed scroll 21. It is led out to an external circuit (not shown) of the closed container 1 through a high pressure chamber 1B formed by the member 25.

At this time, the refrigerant gas which is being compressed in the compression chamber P is introduced into the back pressure space 8 through the back pressure passage 9 and is directed to the end plate 32 of the orbiting scroll 31 so that the back pressure is always directed upward. The wrap tip 33 of the orbiting scroll 31 is thereby provided.
a is constantly pressed against the end plate 22 of the fixed scroll 21, while the thrust bearing member 3
A downward force acts on 6 to be supported by the thrust surface 51a of the thrust receiving portion 51 of the main frame 5.

[0015]

As is clear from the above description, according to the present invention, the bearing portion of the orbiting scroll is provided with a thrust bearing member into which the drive shaft of the electric element is fitted separately, and the thrust bearing member and the orbiting scroll are provided. Since a back pressure space is formed between the back pressure space and the back surface of the end plate, a back pressure passage communicating with the compression chamber is provided in the back pressure space. The back pressure can be applied to the end plate of the orbiting scroll at all times, so that the tip of the wrap of the orbiting scroll can be constantly pressed against the end plate of the fixed scroll, preventing the occurrence of gaps as in the past. Therefore, the occurrence of refrigerant gas leakage during compression can be reduced, and performance characteristics such as volume efficiency and compression efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a scroll compressor according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Airtight container, 1A ... Low pressure chamber, 1B ... High pressure chamber, 5 ... Main frame, 51 ... Thrust receiving part, 51a ... Thrust surface, 6 ... Oldham joint, 7 ... Seal member, 8 ... Back pressure space, 9 ... Back pressure passage, 10 ... Electric element, 13 ... Drive shaft, 14 ... Eccentric shaft part, 20 ... Scroll Compression element, 21 ... Fixed scroll, 22 ... End plate, 23 ... Wrap, 24 ... Discharge port, 25 ... Cover member, 31 ... Orbiting scroll, 32 ... End plate, 33 ... Wrap, 33a ... Wrap tip, 34 ... Mounting part, 35 ... Bearing part, 36 ... Thrust bearing member, 37 ... Boss part.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuya Sato 2-5-5 Keihan Hondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd.

Claims (1)

[Claims] 1. An electric element and a scroll compression element housed in a hermetic container, the scroll compression element revolving without rotating with respect to a fixed scroll fixed to a main frame. And a revolving scroll slidably connected to the thrust receiving portion formed on the main frame via an Oldham coupling,
The fixed scroll and the orbiting scroll end plates are made to face each other, and the spiral wraps are meshed with each other to form a compression chamber consisting of a plurality of compression spaces, while the drive shaft of the electric element is connected to the orbiting scroll. The refrigerant gas fitted to the bearing formed on the back surface of the end plate and supplied to the low-pressure chamber side in the closed container by the eccentric motion in the thrust direction is used to transfer the refrigerant gas from the low-pressure side to the inner high-pressure side. In a scroll compressor that is gradually reduced toward and compressed toward the high-pressure chamber side in the closed container, a thrust bearing member to which the drive shaft of the electric element fits is separately provided in the bearing portion of the orbiting scroll. A back pressure space is provided between the thrust bearing member and the back surface of the end plate of the orbiting scroll, and is connected to the compression chamber in the back pressure space. A scroll compressor having a back pressure passage.