JPH09209945A - Scroll type fluid machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify assembly, reduce machining cost, make precision and absorb thermal expansion simply, in the revolution mechanism of the pin crank of a scroll type fluid machine. SOLUTION: An O ring grooge is machined on the shaft part of a pin tank 8 and the O ring 13 is inserted and a pin crank shaft diameter is inserted with a clearance to a bearing inner race and thereby, the size change of a thermal expansion is absorbed by the elastic force of the O ring 13. Therefore, as the O ring is inserted on the pin crank shaft part and a groove size is machined on the shaft, the machining can be performed precisely at a low cost and a power excess by the unstability of a size maintenance by an inner diameter machining, the increase and generation of an operation sound can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of an orbiting scroll of a scroll type fluid machine using a pin crank as a rotation preventing mechanism.

[0002]

2. Description of the Related Art In a scroll type fluid machine composed of a fixed scroll, an orbiting scroll, a drive shaft and a casing, a fixed scroll is provided as a rotation preventing mechanism of the orbiting scroll, or between the casing fixing portion and the orbiting scroll. Many adopt pink rank. This pin crank cannot be revolved unless it is installed in two or more places. However, due to the stacking of dimensional differences in assembly and the thermal expansion of the scroll, the crank pin collapses and causes "gripping motion". Accuracy error occurs due to the installation of. In order to eliminate this factor, as shown in Japanese Patent Laid-Open No. 4-47121, an elastic body such as an O-ring is fitted on the outer ring and outer periphery of the bearing.

[0003]

In a conventional scroll type fluid machine using a pin crank, an elastic body such as an orbiting scroll, a fixed scroll, or an outer ring of a pin crank bearing of a casing fixing portion and an O ring on the outer circumference thereof. In order to fit the orbiting scroll, the fixed scroll, or the casing fixing portion, a hole for fitting the bearing must be fitted in the outer peripheral portion of the casing fixing portion with a high precision dimension, and then the inner diameter of the hole is further set. The O-ring fitting groove must also be machined with high precision. The O-ring fitting groove is located at a position where it is difficult to confirm the dimensions from the outside, and the groove dimensions are often difficult to measure. Therefore, the O-ring fitting groove cannot be machined to the required tolerance dimension, resulting in mounting failure. Abnormal power is generated, which causes vibration and noise.

[0004]

[Means for Solving the Problems] A fixed portion of a pin crank,
In order to solve the problems such as groove processing when inserting an elastic body such as an O-ring into the fitting hole of the bearing outer ring on both the turning side, in the present invention, the pin crank and the bearing fitting on one side are fitted. It is characterized in that a groove such as an O-ring is formed in the portion, an elastic body such as an O-ring is fitted therein, and a fitting tolerance between the pin crank and the bearing inner ring is a clearance fit with a large clearance.

[0005]

[Function] The pin crank and the bearing inner ring are fitted with a slight clearance, and a rubber elastic body such as an O-ring is interposed between the pin inner crank and the bearing inner ring, so that the orbiting scroll is fixed or fixed for some reason. Even if the scroll is eccentric by a predetermined eccentric amount or more, the gap between the pin crank and the bearing and the buffering force of the rubber elastic body cause the scroll to move in parallel, so that there is no inclination between the pin crank and the bearing. Further, since the pin crank does not have a defective mounting, it is possible to prevent abnormal power from being generated due to the mounting.

[0006]

EXAMPLES Examples of FIGS. 1 to 3 will be described. In FIG. 1, 1 is a fixed scroll which also serves as an outer lid. Reference numeral 2 denotes a casing, which has a fixed portion for 9 bearings, and supports 5 drive shafts via bearings 6 and 7. Reference numeral 4 is an orbiting scroll, and a bearing 7 is fitted to the crank portion 5a of the drive shaft 5. The wrap 3a meshes with the three fixed scroll wraps. Reference numeral 8 denotes a pin crank, which is a rotation preventing mechanism of a 4-orbiting scroll, and a plurality of places are arranged on the inner wall surface of 2 casings around the end plate. Reference numeral 9 is a bearing for the casing fixing portion, and 9'is a bearing for the orbiting scroll.

In FIG. 2, an 8-pin crank equipped with a 13 O-ring is fitted into the inner ring of a 9'bearing that fits into a 4-orbiting scroll. The 8-pin crank is supported with a slight eccentric movement possible. Reference numeral 9 is a fixed part bearing, which is fixedly fitted on the inner wall surface of the two casings. Fig. 3 shows a bearing that fits on the inner wall surface of 2 casings, and a bearing 13
Insert the pink rank. The 8-pin crank is supported with a slight eccentric movement possible. Reference numeral 9'denotes an orbiting scroll bearing which is fitted into the four orbiting scroll by a tight fit.

Next, the operation will be described. In FIG. 2, the rotation of the five drive shafts causes the four-orbiting scroll to revolve around the drive shafts. As a result, the orbiting and fixed scroll wraps are engaged with each other, fluid is sucked through the suction port 11, and the scroll wraps sequentially compress the fluid.
Discharge the fluid from the discharge port. In this case, the four-orbit scroll tries to have an abnormal eccentricity due to the expansion due to the compression heat. At the same time, the fixed side of the 8-pin crank is firmly supported by bearings. Next, on the 4-orbit scroll side of the 8-pin crank, a clearance fit with a large clearance is fitted between the 9-bearing inner ring and the 8-pin crank.
Since the rubber O-ring is interposed, even if the four orbiting scroll causes an eccentricity of a predetermined amount or more due to the various reasons described above,
Allows eccentric movement, the 8-pin crank and 9 bearings do not tilt due to parallel movement, and the 13 O-ring can also absorb shock together with eccentric allowance, and can also prevent creep phenomenon by frictional force.
Although the above description is for the example of FIG. 2, the second example shown in FIG.
Even if the 13 O ring is fitted into the fixed scroll or the 8-pin crank of the fixed portion of the two casings as in the embodiment of FIG. 2 and the clearance fitting is performed, the operation is the same as that of the embodiment of FIG. Is to demonstrate.

[0009]

As the effect of the pin crank bearing cushioning mechanism according to the present invention, the O-ring groove is formed in the hole of the conventional orbiting scroll or the fixed scroll or the hole of the casing fixing portion to absorb the thermal expansion. Since the machining accuracy is extremely difficult and precise measurement dimensions are impossible, the dimension maintenance that absorbs the thermal expansion becomes unstable, which causes excessive power and movement noise. Had a buffering force that was not stable, and retained the drawbacks that the orbiting scroll collapsed and the rasping phenomenon easily occurred.

However, as in the present invention, the O-ring groove is machined in the pin crank so that the groove machining can be carried out precisely and easily, and the dimension can be precisely measured. It is easy to maintain and can absorb eccentric movement such as complete thermal expansion. Further, the present invention has a useful invention effect in that a fitting groove such as an O-ring is formed in the shaft portion of the pin crank and the like, and the cost can be remarkably reduced as compared with the conventional method.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of an embodiment according to the present invention.

FIG. 2 is an enlarged view of a main part in which a pin crank of an orbiting scroll is provided with the configuration of the present invention.

FIG. 3 is an enlarged view of a main part in which a pin crank of a fixed part has the configuration of the present invention.

[Explanation of symbols]

1 ... Fixed scroll 2 ... Casing 3 ... Fixed scroll 4 ... Orbiting scroll 5 ... Drive shaft 6. 7 ... Bearing 8 ... Pin crank 9 ... Casing fixed part bearing 9 '... Swirl scroll bearing 11 ... Suction port 12 ... Discharge port 13 ... O-ring

Claims (2)

[Claims] 1. A fixed scroll and a casing, an orbiting scroll, and a drive shaft, wherein the orbiting scroll constitutes a pin crank as a mechanism for revolving and revolving, and the pin crank is a fixed scroll or a casing fixing portion. The bearing that fits into the bearing is supported by a tight fit to maintain the verticality of the pin crank, and the fitting between the shaft fitting hole of the orbiting scroll side bearing and the pin crank has a large gap. In addition, the scroll type fluid machine is characterized in that an elastic body having a large frictional force such as rubber is interposed between and supported by the pin crank and the shaft fitting hole of the orbiting scroll bearing. 2. A fixed scroll and a casing, an orbiting scroll, and a drive shaft. The orbiting scroll has a pin crank as a mechanism for preventing rotation and revolving, and is fitted into the pin crank and the orbiting scroll. The pin crank fitting hole of the bearing holds the verticality of the pin crank as a fitting fit, and the shaft fitting hole of the bearing fitted into the fixed scroll or the casing fixing portion and the pin crank are fitted with each other. A clearance fit with a large gap should be made, and an elastic body with a large frictional force such as rubber should be interposed between the pin crank and the shaft fitting hole of the fixed scroll or the casing fixed part bearing to support it. Characteristic scroll type fluid machine.