JPH06185477A - Scroll compressor - Google Patents

Abstract

PURPOSE:To provide a scroll compressor having an eccentric structure suitable for a small machine. CONSTITUTION:A groove part 14 having such a shape as arranging a semicircle consecutively on one short side of a rectangle, is bored in an upper part of a driving shaft 10, and a guide groove 17 to guide a guide pin 16 is bored on the center line in a lengthwise direction on the bottom surface. A turning bearing 11 is formed in a cylindrical bushing 11c whose wall is made eccentric, and the guide pin 16 is implanted in the bottom surface on a diameter passing through the smallest wall thickness part. The smallest wall thickness part of the bushing 11c is fitted loosely in the groove part 14 so as to be opposed to a semicircular wall, and it is energized in a semicircular wall direction of the groove part 14 by a spring 15. A V shape groove 18 in parallel with a shaft is arranged on an outer wall on an opposite side of the smallest wall thickness part of the bushing 11c, and a cross sectional shape of the spring 15 is formed in an approximately isosceles triangle, and the top part is engaged with a groove 18.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor, and more particularly to an eccentric structure.

[0002]

2. Description of the Related Art As a scroll compressor of this type according to a conventional example, there is a compressor of a gas body such as Freon shown in FIG. In the figure, in a closed container 1 having a high-pressure chamber 2 inside, a fixed scroll 3 is formed by vertically arranging a spiral wrap 3b on a mirror plate 3a and forming a discharge hole 3c at substantially the center.
Is fixed, and a spiral wrap 4b is erected on one surface of the end plate 4a and a orbiting scroll 4 having an orbiting scroll shaft 4c on the other surface is eccentrically arranged by engaging the wraps. A suction chamber 6 and a discharge chamber 7 are provided at the outer periphery and the center of the compression chamber 5 formed between the wraps, respectively. On the other hand, the fixed scroll 3 is positioned below the orbiting scroll 4 and receives the thrust load thereof, and the fixed scroll 3
A drive bearing 9 is provided in the center of a frame 8 fixed to the drive shaft 10. A swing bearing 11 is provided at the upper end of a drive shaft 10 driven by a motor (not shown) supported by the bearing 9.
Are provided eccentrically, and the orbiting scroll shaft 4c is inserted into the coaxial shaft 11. 3A and 3B are cross-sectional views of the slewing bearing 11, in which FIG. 3A shows the drive shaft 10.
An eccentric circular recess is bored in the upper part of the shaft and a cylindrical bushing 11a having an eccentric thickness is loosely fitted therein, and the orbiting scroll shaft 4c is inserted therein. Further, in the structure shown in (B), a substantially rectangular groove is formed in the upper portion of the drive shaft 10, and a shaft hole is formed in the bushing 11b loosely fitted with a space 12 at one longitudinal end thereof. The orbiting scroll shaft 4c is inserted into this, and the spring 13 is inserted into the space 12 to urge the bushing 11b in the direction in which the amount of eccentricity increases.

Therefore, when the drive shaft 10 rotates, the orbiting scroll shaft 4c is eccentric, and therefore receives a centrifugal force. In the case of FIG. 3 (A), the bushing 11a is pressed to rotate, and as shown in FIG. 2), the outer wall of the wrap 4b is always in contact with the inner wall of the wrap 3b by moving in the direction of increasing the eccentricity in the longitudinal direction.

However, the centrifugal force is proportional to the rotational speed, the amount of eccentricity, and the mass of the orbiting scroll. Therefore, considering the normal rotational speed, the one shown in FIG. 3A is not suitable for a small compressor, and the one shown in FIG. Since the spring compensates for the lack of centrifugal force with a spring, it can be used in a compact compressor, but it has the drawback of poor workability.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the problems of the above-mentioned conventional example, and an object thereof is to provide an eccentric structure suitable for a compact compressor.

[0006]

In order to solve the above problems, according to the present invention, a fixed scroll having a spiral wrap standing on a mirror plate is fixed in a closed container having a high pressure chamber inside, and the mirror plate is also fixed. A spiral wrap is erected on one surface and an orbiting scroll with an orbiting scroll shaft on the other surface is eccentrically provided on the upper side of a drive shaft driven by a motor by eccentrically facing the wrap. In a scroll compressor in which the orbiting scroll shaft is inserted into the orbiting bearing, the orbiting bearing is formed into a cylindrical bushing having an uneven thickness, and a guide pin is planted on the bottom surface on the diameter passing through the minimum thickness portion, A groove having a shape in which a semicircle is continuously provided on one short side of a rectangle is formed on the upper part of the drive shaft, and a guide groove for guiding the guide pin is formed on the center line in the longitudinal direction of the bottom surface of the drive shaft. The minimum thickness of the grayed to face the semicircular wall is loosely fitted in the groove, and characterized by being biased in a semicircular wall direction of the groove is provided a spring.

[0007]

The centrifugal force acting on the orbiting scroll and the biasing force of the spring act on the bushing that is loosely fitted to adjust the amount of eccentricity, and the wrap of the orbiting scroll is always in contact with the wrap of the fixed scroll.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of an eccentric structure of an orbiting scroll according to the present invention will be described below with reference to FIG. 1 which is a cross sectional view of a orbiting bearing 11 and FIG. explain. As shown in the drawing, the slewing bearing 11 is formed in a cylindrical bushing 11c having an uneven thickness, and a guide pin 16 is installed so as to face a diametrical bottom surface that passes through the minimum thickness portion. A groove 14 having a shape in which a semicircle is continuously formed on one short side of a rectangle is formed in the guide groove, and a guide groove 17 for guiding the guide pin 16 is formed on the center line of the bottom surface in the longitudinal direction.
The bushing 11c is provided with a minimum thickness portion so as to face the semicircular wall so as to be loosely fitted in the groove portion 14, and a spring 15 is provided to urge the groove portion 14 in the semicircular wall direction. that time,
The semi-circular wall is located slightly outside the required eccentric position, and the spring pressure is designed to sufficiently press the orbiting scroll shaft 4c against the semi-circular wall when the compressor does not oppose the wrap even if the compressor operates at the minimum rotation speed. Has been done. Further, a V-shaped groove 18 parallel to the axis is formed on the outer wall of the bushing 11c on the side opposite to the minimum thickness portion.
When the cross-sectional shape of the spring 15 is formed into a substantially isosceles triangle and the top portion thereof is engaged with the groove 18, the centrifugal force and the line of action of the spring match, so that the inner wall of the groove portion 14 and the outside of the bushing 11c, or Side wall of guide groove 17 and guide pin 1
Since the sliding of 6 is reduced, it is effective in reducing these abrasions.

Accordingly, when the compressor is operated and the drive shaft 10 is rotated, the orbiting scroll shaft 4c is eccentric, so that the bushing 11c loosely fitted receives the centrifugal force and the groove portion 1 is inserted.
4 in the direction of the semicircular wall to wrap the outer wall of wrap 4b with wrap 3
Always make contact with the inner wall of b to eliminate compression leakage. When operating at low speed rotation, the centrifugal force is reduced, but the contact is continued by the urging force of the spring 15.

[0010]

The orbiting bearing for supporting the orbiting scroll shaft is used as a bushing which is loosely fitted in the eccentric position in the groove provided on the upper part of the drive shaft and is urged by the spring in the direction of increasing the eccentricity. Even if the compressor is installed in the compressor, the orbiting scroll wrap is always in contact with the fixed scroll wrap to prevent compression leakage, and the bushing has a thin wall on the semicircular wall side. The drive shaft can be miniaturized without impairing the force, and the V-shaped groove on the outside of the bushing is pressed by a spring with an isosceles triangular cross section, so the centrifugal force and the action line of the spring match and the sliding of each part is prevented. As a result, wear can be reduced, and a long life can be achieved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part of a scroll compressor according to the present invention.

FIG. 2 is a vertical cross-sectional view of a main part of the scroll compressor according to the present invention.

FIG. 3A is a cross-sectional view of a main part of a scroll compressor according to a conventional example. (B) is a cross-sectional view of a main part of another conventional scroll compressor.

FIG. 4 is a vertical sectional view of a scroll compressor compression unit according to the present invention and a conventional example.

[Explanation of symbols]

 1 Closed Container 3 Fixed Scroll 3b Wrap 4 Orbiting Scroll 4b Wrap 4c Orbiting Scroll Shaft 10 Drive Shaft 11 Orbiting Bearing 11a Bushing 11b Bushing 11c Bushing 14 Groove 15 Spring 16 Guide Pin 17 Guide Groove 18 V-shaped Groove

Claims (2)

[Claims] 1. A fixed scroll in which a spiral wrap is erected on a mirror plate is fixed in a closed container having a high pressure chamber inside,
Similarly, a spiral wrap is erected on one surface of the end plate, and an orbiting scroll having an orbiting scroll shaft on the other surface is eccentrically opposed by engaging the wraps, and is eccentrically located above the drive shaft driven by the motor. In a scroll compressor in which the orbiting scroll shaft is inserted into a provided orbiting bearing, the orbiting bearing is formed into a cylindrical bushing with uneven thickness, and a guide pin is planted on the bottom surface on the diameter passing through the minimum thickness portion. Then, a groove portion having a shape in which a semicircle is continuously provided on one short side of a rectangle is formed on the upper portion of the drive shaft, and a guide groove for guiding the guide pin is formed on the center line in the longitudinal direction of the bottom surface thereof. A scroll compressor characterized in that a minimum thickness portion of the bushing is opposed to a semicircular wall so as to be loosely fitted in the groove portion, and a spring is provided to urge the bushing portion in the semicircular wall direction. 2. A V-shaped groove parallel to the shaft is provided on the outer wall of the bushing on the side opposite to the minimum wall thickness portion, the cross-sectional shape of the spring is formed into an approximately isosceles triangle, and the top portion thereof is engaged with the groove. The scroll compressor according to claim 1, wherein the scroll compressor is provided.