JP2005048685A - Scroll compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a scroll compressor with a back pressure control mechanism, solving the problem on a back pressure control mechanism component when formed by press-fit, that the component accuracy of a fixed scroll is impaired by press-fit distortion to increase leakage loss and lower performance resulting in lower reliability due to contact pressure rise. <P>SOLUTION: A circumferential groove is provided in the fixed scroll 10 in which a back pressure pin 42 is pressed, at a given distance from the back pressure pin 42. Thereby, press-fit distortion which occurs in pressing the back pressure pin therein is absorbed. Otherwise, a counter boring or a slit is provided in the back pressure pin itself to avoid the press-fit distortion. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention is a compressor used for an air conditioner, a refrigeration apparatus, etc., and by suppressing deformation of a fixed scroll, it reduces leakage loss and assembly distortion of a machined surface processed with high accuracy. The present invention relates to a scroll compressor capable of improving performance and reliability.

  As a conventional scroll compressor, an arcuate compression chamber is formed by meshing a fixed scroll having a spiral scroll lap formed upright on an end plate and a turning scroll to form an arcuate compression chamber, and the rotating scroll is restrained from rotating with respect to the fixed scroll. In some cases, the compression operation is performed by reducing the volume while moving the compression chamber from the outer peripheral side toward the inner periphery by swirling in a state. This scroll compressor has a problem that the compressed gas leaks from the meshing portion of the orbiting scroll and the fixed scroll, causing a reduction in efficiency, and various countermeasures have been proposed (for example, patents). Reference 1). FIG. 8 shows a conventional hermetic scroll compressor described in Patent Document 1. In FIG.

In FIG. 8, 10 is a fixed scroll, 11 is a turning scroll, and 30 is a back pressure control mechanism provided in the fixed scroll. By operating so that the back pressure chamber 29 is maintained at a certain pressure or higher, The gap between the fixed scroll and the orbiting scroll is reduced, and leakage loss is reduced.
JP 2002-310076 A (pages 2 to 3, FIG. 1)

  However, the back pressure control valve in the back pressure control mechanism formed in the fixed scroll is configured to be press-fitted into the fixed scroll, and distortion may occur in the fixed scroll during the press-fitting. Originally in the design and manufacture of scroll compressors, the sliding surfaces of the fixed scroll and the orbiting scroll are designed so that there is no leak gap due to high precision machining. A gap is formed on the surface that is in close contact with the scroll end plate surface, and efficiency is reduced due to leakage loss, particularly under low speed and low load conditions. In addition, when the deformation of the fixed scroll top surface is greatly swelled, the strained portion on the top surface and the end plate surface of the orbiting scroll slide to cause pressure concentration, resulting in sliding marks, etc. In addition, there may be a problem in terms of reliability.

  An object of the present invention is to solve the above-mentioned conventional problems, and to provide a scroll compressor capable of realizing assembly without impairing the original high-precision machining, and at the same time improving performance and reliability. To do.

  In order to solve the above-described conventional problems, the scroll compressor according to the present invention is provided with a portion that absorbs press-fitting strain in either the back pressure control valve that press-fits the fixed scroll or the fixed scroll.

  With this configuration, it is possible to reduce the press-fitting distortion when assembling the back pressure control mechanism to the fixed scroll, and to obtain a sliding surface that does not impair the high-precision machining state during machining.

  According to the scroll compressor of the present invention, it is possible to provide a scroll compressor that prevents distortion of the fixed scroll that occurs when assembling the back pressure control mechanism and maintains a highly accurate machining state.

  Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1)
FIG. 1 is a cross-sectional view of a scroll-type hermetic compressor according to an embodiment of the present invention.

  In FIG. 1, 11 is a turning scroll, and 10 is a fixed scroll, which are meshed to form a compression chamber 32. 14 is a suction hole for sucking 14 refrigerant, 15 is a discharge hole for discharging compressed refrigerant, 12 is an Oldham joint for restraining the rotation of the orbiting scroll 11, and the swivel is driven by the rotation of the rotating shaft 6 driven by the electric motor 3. Compression is performed by the scroll 11 turning. Reference numeral 31 denotes a back pressure control mechanism provided in the fixed scroll 10, which includes 40 back pressure control valves, 41 control springs, and 42 back pressure pins, and 29 intermediate chambers provided on the back of the orbiting scroll 11. When the intermediate chamber 29 reaches a certain pressure or higher, the back pressure control valve 40 is opened and communicated with the compression chamber 30. As a result, the pressure in the intermediate chamber 29 is kept constant.

  FIG. 2 is a view showing the shape of the fixed scroll 10 in FIG. 1 as viewed from above. In FIG. 2, a back pressure pin 42 is press-fitted into the fixed scroll 10. Further, by providing a circumferential groove such as 43 at a certain distance from the back pressure pin 42, the pressure distortion generated when the back pressure pin is pressed is absorbed, and the back pressure is not exerted on the sliding surface of the fixed scroll 10. The control mechanism can be assembled, and the performance and reliability can be improved.

(Embodiment 2)
FIG. 4 is a view showing the shape of the fixed scroll 10 in FIG. 1 as viewed from above. In FIG. 4, a back pressure pin 42 is press-fitted into the fixed scroll 2. Further, by providing counterbore 44 in the cross-sectional view of FIG. 5 on the upper surface of the back pressure pin 42, it is possible to assemble a back pressure control mechanism that absorbs press-fitting strain that occurs during press-fitting and does not exert strain on the sliding surface of the fixed scroll 10. It is possible to improve performance and reliability.

(Embodiment 3)
FIG. 6 is a diagram showing a shape of the fixed scroll 10 in FIG. 1 as viewed from above. In FIG. 6, a back pressure pin 42 is press-fitted into the fixed scroll 10. 7 is provided on the upper surface of the back pressure pin 42, it is possible to assemble a back pressure control mechanism that absorbs the press-fitting strain generated during press-fitting and does not exert a strain on the sliding surface of the fixed scroll 1. It is possible to improve performance and reliability.

Sectional drawing of the compressor in Embodiment 1 of this invention The figure which shows the shape which looked at the fixed scroll 10 in FIG. 1 from the upper surface Sectional drawing of the back pressure control part 40 in Embodiment 1 of this invention. The figure showing the shape which looked at the fixed scroll 10 in Embodiment 2 of this invention from the upper surface Sectional drawing of the back pressure pin 42 in Embodiment 2 of this invention The figure showing the shape which looked at the fixed scroll 10 in Embodiment 3 of this invention from the upper surface Sectional drawing of the back pressure pin 42 in Embodiment 3 of this invention Sectional view showing a conventional scroll compressor

Explanation of symbols

DESCRIPTION OF SYMBOLS 3 Electric motor 6 Rotating shaft 10 Fixed scroll 11 Orbiting scroll 12 Oldham coupling 14 Suction hole 15 Discharge hole 29 Intermediate chamber 30 Compression chamber 40 Back pressure control valve 41 Control spring 42 Back pressure pin 43 Circumferential groove 44 Back pressure pin Counterbore 45 Back Pressure pin Slit

Claims (4)

A fixed scroll in which a spiral scroll wrap is formed upright on the end plate, and a revolving scroll in which a spiral scroll wrap is also formed upright on the end plate, and the compressor and the compression chamber inside are opposite to the wrap portion of the orbiting scroll. Forming a back pressure chamber that is shut off in pressure, and using the differential pressure between the pressure in the compression chamber and the back pressure chamber to bring the fixed scroll and the end plate surface of the orbiting scroll into close contact with each other A scroll compressor that reduces leakage loss and achieves high efficiency even under low speed and low load conditions. The fixed scroll has a back pressure control mechanism for controlling the pressure in the back pressure chamber, and is controlled in the previous period. When the back pressure pin forming the mechanism is press-fitted into the fixed scroll, a relief is provided to reduce the press-fitting distortion caused thereby, and performance and reliability Scroll compressor, characterized in that to improve. The scroll compressor according to claim 1, wherein a recess is provided on an outer periphery so as to surround the back pressure pin on the back side of the fixed scroll, and the press-fitting strain generated when the back pressure control valve is press-fitted is reduced. A scroll compressor characterized by improving performance and reliability. 2. The scroll compressor according to claim 1, wherein when the back pressure control valve is press-fitted, the back pressure pin press-fitted into the back side of the fixed scroll is subjected to a counterbore process so as to reduce press-fitting distortion at the time of press-fitting. A scroll compressor characterized by reducing generated press-fitting distortion and improving performance and reliability. 2. The scroll compressor according to claim 1, wherein the back pressure pin is press-fitted into the back pressure pin by press-fitting the back pressure pin by subjecting the back pressure pin to slit processing to reduce press-fitting distortion during press-fitting. A scroll compressor characterized by reducing press-fitting distortion and improving performance and reliability.

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