JPH06221280A - Scroll compressor - Google Patents

Abstract

(57) [Summary] [Object] The present invention, in a scroll compressor with a two-bearing structure, improves the mountability of the sub-bearing and keeps the clearance of the sub-bearing part constant, so that it is locally attached to the main bearing. An object of the present invention is to provide a scroll compressor which can prevent one-sided contact and also can prevent generation of noise in a low frequency region due to a large clearance, which is inexpensive, has high performance, and has high reliability. In order to achieve the above object, the present invention is formed by cold working plastic working including an annular wall for joining a support leg to an inner surface of a case and a flat portion extending from the annular wall to an inner diameter side of the case. It is assumed that it is made of a steel plate, and the flat bearing is used as a support portion of the secondary bearing, and after the secondary bearing is centered and adjusted with respect to the crankshaft, it is welded and fixed to the flat portion of the support leg.

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 a scroll compressor suitable for use in an air conditioner, a refrigerator, etc., which is suitable for improving reliability by an inexpensive means.

[0002]

2. Description of the Related Art The structure and fixing method of a sub-bearing in a conventional scroll compressor having a two-bearing structure are as follows.

As shown in FIG. 2, the sub-bearing 9 comprises a spherical bearing 9A slidably provided on the shaft 6 and a sub-bearing housing 9B for press-fitting and supporting the spherical bearing 9A.
The auxiliary bearing housing is provided with a hole into which the bolt 21 can be inserted, and the support leg 13 supports the bolt 2 to support the auxiliary bearing 9.
It is fixed by 1.

[0004]

The method of mounting the auxiliary bearing as in the above prior art has the following problems.

As shown in FIG. 2, since the auxiliary bearing 9 provided at the lower portion of the electric motor 10 is fixed to the supporting leg for supporting the electric motor 10 with bolts, the number of parts is small, the assembly time is long, and the auxiliary bearing 9 is also small. When installing the bearing, the electric motor 1
In order to secure an air gap between the stator 11 and the rotor 12 of 0, and to ensure smooth rotation of the crankshaft 6, it is necessary to make the axes of the auxiliary bearing housings 9b of the auxiliary bearings 9 substantially coincide. Therefore, the pitch diameter of the auxiliary bearing mounting screw hole of the support leg welded and fixed to the inner diameter of the closed case 1 and the pitch diameter of the bolt hole of the auxiliary bearing are formed to be substantially the same, and a screw for mounting the auxiliary bearing is formed. There was a problem that it was necessary to ensure smooth rotational movement between the spherical bearing and the crankshaft when tightening.

The present invention has been made to solve the above-mentioned problems of the prior art. Since the auxiliary bearing is welded and fixed to the support leg, the installation time can be shortened and the number of parts can be reduced.
By using this low-priced and simple auxiliary bearing structure and by using the simple centering technique together, it is possible to provide a scroll compressor excellent in quality as well as being reduced in manufacturing cost.

When fixing the auxiliary bearing to the support leg by welding, the residual stress due to welding is applied to the welded portion due to the heating by welding, the auxiliary bearing housing is deformed, and the circularity of the inner diameter of the housing may change. There is a nature. The deformation causes a change in the clearance between the spherical bearing outer diameter and the sub bearing housing inner diameter, which causes the following problems.

When the clearance is reduced, the centering property of the sub bearing is lost, a large load is applied to the main bearing, and the local contact with the crank shaft in the main bearing becomes a problem. Further, when the clearance becomes large, there is a problem that whirling of the spherical bearing increases and noise in the low frequency band becomes large.

The present invention has been made to solve the above-mentioned problems, and has a simple structure and can reduce deformation due to welding.
It is possible to provide an inexpensive, high-performance, highly reliable scroll compressor.

[0010]

In order to achieve the above object, the present invention comprises a cold plastic material which comprises an annular wall for joining a support leg to the inner surface of a case and a flat portion extending from the annular wall to the inner diameter side of the case. It is assumed that it is made of a steel plate formed by working, and the flat portion is used as a support portion of the auxiliary bearing and the auxiliary bearing is centered and adjusted with respect to the crankshaft and then fixed to the flat portion of the support leg by welding.

Further, the sub-bearing is a spherical bearing having an inner surface on which the crankshaft is slidably fitted and a smooth spherical outer surface, and a spherical bearing slidably opposed to the outer surface of the spherical bearing. The auxiliary bearing housing has an inner surface and has an annular recess in a part of the inner surface, and the spherical bearing is slidably included. An annular groove is provided on both end surfaces of the mounting surface or the mounting surface and the non-mounting surface.

[0012]

The function of the above technical means is as follows.

Since the auxiliary bearing is fixed to the support leg by welding, the number of parts such as mounting screws can be reduced and the mounting time can be shortened.

Further, when the auxiliary bearing that supports the lower end of the crankshaft is fastened by welding, deformation is absorbed and suppressed by the groove provided on the auxiliary bearing housing mounting surface, and the inner diameter of the housing in which the auxiliary bearing inner ball slides is You can maintain a perfect circle shape with accuracy, there is no change in the increase or decrease of clearance due to welding, the automatic centering function of the auxiliary bearing is not lost, and abnormal partial contact with the crankshaft or local contact with the crankshaft in the main bearing part There is an action that can prevent.

[0015]

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

In FIG. 1, 1 is a closed case, 2 is a compression mechanism portion housed in the upper part of the closed case 1, 3 is a fixed scroll in which a spiral wrap 3b is upright on an end plate 3a, and 4 is a fixed scroll. , A spiral wrap 4b is vertically erected on the end plate 4a, and the fixed scroll 3 and the rotary scroll 4 form a compression chamber 5 by meshing the respective laps 3b, 4b inward. .

Reference numeral 6 denotes a crankshaft, the eccentric portion 6a of which is fitted into the boss portion of the orbiting scroll 4 to transmit the rotational force of the electric motor 10 to revolve the orbiting scroll 4. The orbiting scroll 4 is an Oldham ring (not shown).
The action prevents rotation.

Reference numeral 7 denotes a frame which is welded and fixed to a closed case which houses the orbiting scroll 4 and fastens the fixed scroll 3, 8 is a main bearing which is provided on the frame 7 and rotatably supports the crankshaft 6, and 9 is The auxiliary bearing 9 is located on the side opposite to the electric motor (lower side of the electric motor 10) with respect to the main bearing 8, and the auxiliary bearing support 13 is a bearing holder of the auxiliary bearing 9.

The electric motor 10 includes a stator 11 and a rotor 12.
And the crankshaft 6 connected to the rotor 12 is
It is configured to be supported by a main bearing 8 and a sub bearing 9 provided on both sides of the electric motor 10.

The main bearing 8 is a plain slide bearing having a generally inner diameter surface, and the sub bearing disposed below the electric motor 10 is a spherical bearing 9A and a sub bearing housing having a spherical inner diameter. 9B is a self-aligning bearing. The shape of the auxiliary bearing housing 9B is shown in FIGS.
As shown in FIG. The sub bearing housing is provided with annular grooves 9C and 9D to prevent deformation due to welding.

Next, the assembling of the auxiliary bearing 9 and the support leg 13 in FIG. 1 which characterizes this embodiment will be described in detail with reference to FIG.

The support leg 13 includes an annular wall 13a which is press-fitted into the case 1 and welded to it, a flat surface portion continuous with the annular wall 13a, and an inner diameter side flat surface portion 13b having a stepped recess in the central portion. And a hole having a diameter larger than the outer diameter of the sub-bearing portion of the crankshaft 6 and smaller than the outer diameter of the bearing housing 9B of the sub-bearing 9 is provided in the center of the inner diameter flat surface portion 13b. The auxiliary bearing portion of the shaft 6 is passed through. The support leg 13 is made of a steel plate and is formed by high-precision cold plastic working of a steel plate, and can be formed in a short time. To attach the support legs 13 to the inner surface of the case 1, the support legs 13 are welded to the inner surface of the case 1. Since the support leg 13 is thus provided with the annular wall 13a that abuts the inner surface of the case 1 with a large area, it is easy to press the support leg 13 into the case 1 and attach it in a stable state. Further, in contrast to the case where the auxiliary bearing 9 is supported on the back side electric motor side of the case 1, the portion to be welded to the case 1 can be on the front oil reservoir side of the case 1, and the welding work is facilitated.

In the state shown in FIG. 3, the auxiliary bearing 9 drawn in as described above is attached to the auxiliary bearing portion of the crankshaft 6 and mounted on the inner diameter side flat surface portion 13b of the support leg 13. After that,
The constituent members of the sub bearing 9 are centered, and the sub bearing 9 is fixed to the support leg 13 by welding.

[0024]

As described in detail above, according to the first aspect of the present invention, since the auxiliary bearing is centered with respect to the crankshaft and is welded and fixed to the support leg, the compressor main body in the case, Even if there is a gap between the axis of the closed case and the axis of the crankshaft due to a combination of complicated related parts such as mounting of support legs, the auxiliary bearing acts as a smooth sliding bearing with respect to the crankshaft. Noise generated from the auxiliary bearing can be prevented.

According to the second aspect of the present invention, the deformation of the auxiliary bearing housing to the support leg due to welding can be reduced, and a highly reliable compressor with a small number of parts can be provided.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a scroll compressor according to an embodiment of the present invention.

FIG. 2 is a vertical sectional view of a conventional scroll compressor.

FIG. 3 is a plan view of an auxiliary bearing housing according to an embodiment of the present invention.

FIG. 4 is a sectional view taken along the line AA of FIG.

5 is a sectional view taken along the line AA of FIG. 3 according to another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Sealed case, 2 ... Compression mechanism part, 3 ... Fixed scroll, 4 ... Orbiting scroll, 3a, 4a ... End plate, 3b, 4
b ... Wrap, 4c ... Orbiting scroll bearing, 5 ... Compression chamber,
6 ... Crank shaft, 7 ... Frame, 8 ... Main bearing, 9 ... Sub bearing, 9A ... Spherical bearing, 9B ... Sub bearing housing, 9
C, 9D ... Annular groove, 10 ... Electric motor, 18 ... Intermediate pressure chamber, 1
9 ... oil sump.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koichi Inaba 800 Tomita, Ohira-cho, Shimotsuga-gun, Tochigi Prefecture Living Equipment Division, Hitachi Ltd.

Claims (2)

[Claims] 1. A orbiting and fixed scroll having an end plate and a spiral wrap portion standing upright on the end plate, a crankshaft and an electric motor unit for driving the orbiting scroll, and a rotation preventing mechanism for the orbiting scroll and supporting the rotation preventing mechanism. Has a frame part,
In a scroll compressor in which a sub-bearing portion is provided on the side opposite to the frame with the electric motor portion as a boundary, the sub-bearing portion is slidable on both sides of the crankshaft and the inner diameter of the sub-bearing housing, and the sub-bearing housing is welded. A scroll compressor characterized by being fixed. 2. A scroll compressor according to claim 1, wherein an annular groove is provided between the outer peripheral welding portion and the inner diameter sliding portion on the end surface of the sub bearing housing.