JPH05187376A - Completely closed electric compressor - Google Patents

Abstract

PURPOSE:To simplify the machining and assembly of a completely closed electric compressor for refrigerating and chilling equipment by providing a plane part which has a rotation shaft insertion hole in the middle, providing a support saddle whose radial outer side is formed as an annular wall which is welded to the inner peripheral face of a case, and centering and welding a sub-bearing for a rotation shaft to a flat face. CONSTITUTION:A support saddle for an annular sub-bearing 11 is molded by applying cold plastic working to a steel plate and the annular wall 12a of the support saddle 12 is welded and fixed to the inner face of a case 13a. The center of the support saddle 12 is a flat face 12c and a hole 12d into which a rotation shaft is inserted is formed thereon. A sub-bearing 11 is installed in the hole 12d. The sub-bearing comprises a spherical face bearing 11a having a spherical-surface-like outer face in which a sub-bearing 4c for a rotation shaft 4 is fitted in a manner that it can be oscillated, as well as an outer ring 11b and an inner ring 11e. The sub-bearing 11 is installed in the sub-bearing part 4c of the rotation shaft 4, adjusted in centering and then welded to the support saddle 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to a totally hermetic electric compressor used in refrigerating and cooling equipment, and more particularly to a two-bearing fully hermetic electric compressor for avoiding concentration of sliding load. Of the secondary bearing of.

[0002]

2. Description of the Related Art As a structure of a sub-bearing in a conventional two-bearing structure fully hermetic electric compressor, for example, Japanese Patent Application Laid-Open No. 1-17
As described in Japanese Patent No. 0774, there is an example in which a general ball bearing in which a spherical body is rollably fitted between an inner ring and an outer ring is press-fitted into a boss hole of a support leg formed by cast iron or forging.

[0003]

However, the conventional sub-bearing mounting structure for such a hermetically-sealed electric compressor has the following problems. That is, cast iron or forged material has poor forming accuracy, and if cast iron or forged material having such poor forming accuracy is used as a constituent material of the supporting leg, equipment and processing cost for machining them are required. Manufacturing costs will rise sharply.

Further, in order to secure the precision of the inner diameter of the case and the center of the auxiliary bearing which require precise centering at the time of assembly, the concentricity between the annular outer diameter of the support leg and the boss hole into which the ball bearing is press-fitted is secured. Needless to say, the case is inferior in rigidity and deforms when the stator of the electric motor is fitted, but even in this case, in order to improve the accuracy of the combination of the case and the supporting legs, the inner surface of the case is also machined. There are many disadvantages in terms of manufacturing cost including assembly, such as the necessity of processing.

Further, in the above-mentioned conventional fully hermetic electric compressor, a ball rolling bearing is used as an auxiliary bearing.
In products such as home room air conditioners that use such fully enclosed electric compressors, operating noise is a critical factor that determines its quality, and rolling bearings should avoid the occurrence of hitting noise due to rolling of balls. Can't
It is subject to complaints from customers who want to reduce noise.

The object of the present invention is to solve the above problems, to simplify the pre-processing and assembly, to use a low-priced and simple auxiliary bearing structure, and to use a simple centering technique together, thereby reducing the manufacturing cost. It is also to provide a fully enclosed electric compressor of excellent quality.

[0007]

In order to achieve the above object, the present invention comprises 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, which is cold. The flat bearing is made of a steel sheet formed by plastic working, and the flat bearing is used as a supporting portion of the rotary shaft auxiliary bearing,
After the centering adjustment with respect to the rotating shaft, it is assumed that the supporting leg is welded and fixed to the flat surface portion.

According to the present invention, the sub-bearing is a spherical bearing having an inner surface on which the rotary shaft is slidably fitted and a smooth spherical outer surface, and is slidable on the outer surface of the spherical bearing. An outer ring having a spherical inner surface facing each other and having an annular recess in a part of the inner surface, and being press-fitted into the recess of the outer ring to be in firm contact with the outer ring, An inner ring having a spherical inner surface slidably opposed to the outer surface is formed, and the spherical bearing is slidably included by the outer ring and the inner ring.

[0009]

[Function] Since the support legs are formed by high-precision cold plastic working of steel plates, machining is required in the post-process compared to the support legs made by casting or forging with inferior precision that was required in conventional compressors. Not. Therefore, the supporting leg to be used is manufactured with high precision in a short time and is inexpensive. Further, even if the center of the case and the center of the rotary shaft are misaligned, the sub bearing enables the smooth sliding bearing of the rotary shaft.

Not only is the inner surface of the spherical bearing slidable with respect to the rotary shaft, but the outer surface of the spherical bearing is slidable with the outer ring and the inner ring. The smooth sliding bearing action is realized.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical cross-sectional view showing an embodiment of a totally hermetic electric compressor according to the present invention, in which 1 is a compressor body, 1a is a compression chamber, 2 is a frame, 3 is a main bearing, 4 is a rotary shaft, 4a is a main shaft portion, 4b is an eccentric portion, 4c is an auxiliary shaft portion, 5 is an orbiting scroll, 5a is a boss portion, 5b is a wrap, 6 is a fixed scroll, 6a is a wrap, 6b is a discharge port, 7 is a suction pipe, 8 is an Oldham ring, 9 is a bolt, 10 is an electric motor, 10a is a rotor, 10b is a stator, 11 is a sub-bearing, 11a is a spherical bearing, 11b is an outer ring, 12 is a support leg of the sub-bearing, and 13 is a closed container. , 13a is a case, 13b is a lid chamber, 13
c is a bottom chamber and 14 is a lubricating oil.

In the figure, the closed container 13 is formed by welding a lid chamber 13b to one side of a cylindrical case 13a and a bottom chamber 13c to the other side. This closed container 13
An electric motor 10 and a compressor main body 1 are provided inside by being connected by a rotary shaft 4. The rotating shaft 4 is composed of a main shaft portion 4a and an eccentric portion 4b. The central portion of the main shaft portion 4a is press-fitted or shrink-fitted into the rotor 10a of the electric motor 10, and the stator 10b of the electric motor 10 is shrink-fitted to the inner surface of the case 13a. It is joined by. In addition, the main shaft portion 4a of the rotating shaft 4 is
0 is slidably supported by a main bearing 3 which is integrated with a frame 2 provided above 0, and a sub shaft portion 4c of the rotary shaft 4 is press-fitted and welded to a case 13a below the electric motor 10. The auxiliary bearing 11 is welded to the auxiliary bearing support leg 12 in a state where it is slidably supported.

The bearing 11 includes a spherical bearing 11a having a cylindrical inner diameter into which the sub bearing 4c of the rotary shaft 4 is slidably fitted.
An outer ring 11b having an inner spherical surface that freely slides on the outer spherical surface of the spherical bearing 11a and an annular protruding portion on the outer diameter side, and an inner ring having an outer diameter portion press-fitted into the inner diameter of the annular protruding portion and an inner spherical surface. It consists of a ring 11c.

The compressor body 1 is mounted above the frame 2 and is mainly composed of an orbiting scroll 5 and a fixed scroll 6. A boss portion 5a is formed at the center of the lower surface of the orbiting scroll 5.
The eccentric portion 4b at the upper part of the rotary shaft 4 is provided in the hollow portion provided in a.
Has been inserted. As a result, the orbiting scroll 5 rotates eccentrically with the rotation of the rotating shaft 4, but the Ordham ring 8 provided on the upper surface of the frame 2 causes the orbiting scroll 5 to rotate.
Is prevented from rotating and moves on a circular orbit centered on the center of the rotating shaft 4. However, in the following description, this movement of the orbiting scroll 5 is referred to as the revolution. The fixed scroll 6 is fixed to the frame 2 with bolts 9.

A wrap 5b is spirally provided on the upper surface of the orbiting scroll 5, and a spiral wrap 6a is also provided on the lower surface of the fixed scroll 6 disposed on the upper part of the orbiting scroll 5, so that the orbiting scroll 5 is wrapped. 5b and the wrap 6a of the fixed scroll 6 are fitted into each other. The spiral shapes of the wraps 5b and 6a are different, and the tip end portions of the spirals of the wraps 5b and 6a and the wraps 5b and 6a are different from each other.
The walls of a are in contact with each other at two points. These wraps 5
The compression chamber 1a is formed by the wall surfaces of b and 6a, their tips, and the contact points of these wall surfaces. When the orbiting scroll 5 revolves, these contact points on the wall surfaces of the laps 5b and 6a move along the spiral trajectory, and the contact of the tip ends of the laps 5b and 6a does not change, so that the compression chamber 1a becomes narrow. To go.

A discharge port 6b is provided in the vicinity of the center of the fixed scroll 6, and a suction pipe 7 communicates with a compression chamber 1a formed by the wrap 5b of the orbiting scroll 5 and the wrap 6a of the fixed scroll 6. ..

The compressor body 1 is constructed as described above. The compressor body 1 is inserted into the case 13a in which the bottom chamber 13c is attached, and the center of the compressor body 1 and the inner diameter of the case 13a are inserted. After aligning, the outer peripheral surface of the frame 2 and the inner surface of the case 13a are fixed by spot welding.

When the rotating shaft 4 is rotated by the electric motor 10, the orbiting scroll 5 revolves as described above, and the volume of the compression chamber 1a gradually decreases with each revolution. In such an operation, the refrigerant gas from the evaporator (not shown) of the refrigeration cycle is supplied to the compression chamber 1a through the suction pipe 7, is gradually compressed, and is discharged from the discharge port 6a into the closed container 13. Thereafter, this refrigerant gas is sent from a discharge pipe (not shown) to a condenser (not shown) of the refrigeration cycle.

On the other hand, a lubricating oil 14 is provided on the bottom of the closed container 13.
When the rotating shaft 4 rotates, the lubricating oil 14 rises inside the oil supply hole provided along the central axis of the rotating shaft 4, and the inner surface of the main bearing 3 and the sub bearing 11 and the rotating shaft are rotated. Axis 4
Is supplied between the eccentric portion 4b and the boss portion 5a of the orbiting scroll 5, whereby the hermetic electric compressor is smoothly operated.

The auxiliary bearing 1 in FIG. 1 which characterizes this embodiment
1, as shown in FIG. 2, a spherical bearing 11a of the sub bearing portion 4c of the rotary shaft 4 (FIG. 1) has an outer surface 11a ₂ of the inner surface 11a ₁ and the spherical shape which fits slidably, the spherical Bearing 1
A spherical inner surface 11 that slides freely with the outer surface 11a _{2 of} 1a
b ₁ a recess 11b ₂ provided annularly to the inner surface 11b ₁
An outer ring 11b with a, and a inner ring 11c having a spherical inner surface 11c ₁ to slide freely between the outer surface 11a ₂ of the recessed portion 11b ₂ on the indented by spherical bearing 11a. According to the case of assembling the sub-bearing 11, inserts a spherical bearing 11a as the outer surface 11a ₂ spherical to the inner surface 11b ₁ of the outer ring 11b strikes in the outer ring 11b, and thereafter, the recessed portion 11b of the outer ring 11b Inner ring 1 to ₂
Press in 1c. As a result, the auxiliary bearing 11 is configured as shown in FIG. 1, but in this case, the outer surface 11a ₂ of the spherical bearing 11a is the inner surface 11b ₁ of the outer ring 11b, and the inner ring 1b.
It is slidable with the inner surface 11c _{1 of} 1c, so that the spherical bearings 11a are slidably included in the respective rings 11b, 11c. The spherical bearing 11a and the rings 11b and 11c are made of steel plate or steel material and are formed by plastic working or cutting.

Next, the assembly of the sub-bearing 11 and the support leg 12 in FIG. 1 which characterizes this embodiment will be described in more detail with reference to FIG. However, in the figure, 12a is an annular wall, 12b is an outer diameter side flat surface portion, 12c is an inner diameter side flat surface portion,
12d is a hole, and the portions corresponding to those in FIG.

The support leg 12 is press-fitted into the case 13a and joined thereto, an annular wall 12a, an outer diameter side flat surface portion 12b continuous with the annular wall 12a, and a recess continuously formed in the outer diameter side flat surface portion 12b. And the outer diameter of the outer ring 11b of the sub-bearing 11 is larger than the outer diameter of the sub-bearing portion 4c of the rotary shaft 4 at the center of the inner-diameter side flat portion 12c. A hole 12d having a smaller diameter is provided, and the auxiliary bearing portion 4c of the rotary shaft 4 is passed through the hole 12d. The support leg 12 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 leg 12 to the inner surface of the case 13a, the annular wall 12a of the support leg 12 is attached to the case 1.
3a is press-fitted into the inner surface of the case 13a, and then the annular wall 12a is welded to the inner surface of the case 13a. Thus, the support leg 12 is provided with the annular wall 12a that abuts the inner surface of the case 13a with a large area. Support leg 12 to case 13
It is easy to press fit into a and stably attach, and the auxiliary bearing 11 is supported in the inner part of the case 13a, whereas the part to be welded to the case 13a is located on the front side of the case 13a. And welding work becomes easy.

In the state shown in FIG. 3, the auxiliary bearing 11 assembled as described above is attached to the auxiliary bearing portion 4c of the rotary shaft 4,
The support leg 12 is mounted on the flat surface portion 12b on the inner diameter side. After that, the constituent members of the auxiliary bearing 11 are centered and welded to fix the auxiliary bearing 11 to the support leg 12, which will be described with reference to FIG. However, in FIG. 3, 15 is a centering device, 16 is a welding torch, 17 is a secondary bearing temporary fixing jig, and the same reference numerals are given to the parts corresponding to the above drawings.

The sub-bearing 11 is mounted on the sub-bearing portion 4c so that the inner surface 11a ₁ (FIG. 2) of the spherical bearing 11a is slidable with the sub-bearing portion 4c of the rotary shaft 4, and the supporting leg 1 is attached.
2 is installed on the inner surface side flat surface portion 12c of the auxiliary bearing portion 4c and the spherical bearing 11a of the auxiliary bearing portion 4c by rotating the rotating shaft 4 at a low speed by using the centering device 15 that also has a rotational torque measuring function and the like.
Centering the clearance with the inner surface 11a ₁ of the sub-bearing 11 while adjusting the position of the sub-bearing 11, and when the centering is completed, the sub-bearing temporary fixing jig 17 supports the sub-bearing 11 The inner surface side flat part 12c of 12 is pressed and temporarily fixed. Then, the supporting legs 12 are formed by the plurality of welding torches 16.
A plurality of overlapping points of the auxiliary bearing 11 are spot-welded. At this time, welding uses a non-consumable electrode without filler,
By attaching them together, a normal welded state with relatively little spatter can be obtained.

In this way, the sub-bearing 11 supports the support leg 12
2, the auxiliary bearing 11 has the auxiliary shaft portion 4c of the rotary shaft 4 slidable on the inner surface 11a ₁ of the spherical bearing 11a and the outer surface 11 of the spherical bearing 11a as described in FIG.
a ₂ is the inner surface 11b _{1 of the} outer ring 11b and the inner ring 11c
Since it is slidable with respect to the inner surface 11c ₁ of the rotary shaft 4, even if the straightness of the rotary shaft 4 is slightly low and there is bending deformation, the eccentricity of the rotary shaft 4 due to this bending deformation is absorbed by these sliding parts. can do. Therefore, the sub bearing 11 serves as a sliding bearing that smoothly moves with respect to the sub shaft portion 4c of the rotary shaft 4, and the friction between them can be reduced, and the generation of friction noise can be prevented.

Further, since the case 13a is produced by the steel plate plastic working in terms of cost, the accuracy is inferior, and the compressor body 1, the electric motor 10, the rotary shaft 4 and the like are mounted in the case 13a and the support legs 12 are attached. When fixed by welding, it is difficult to obtain concentricity between the compressor body 1 and the case 13a.
A deviation occurs between the center of a and the center of the rotary shaft 4.
However, in the above embodiment, the inner surface side flat surface portion 1 of the support leg 12 is
2c is provided with a hole 12d into which the auxiliary shaft portion 4c of the rotary shaft 4 is fitted with a margin even if the center of the case 13a and the center of the rotary shaft 4 are misaligned, and the auxiliary shaft portion passing through this hole 12d is provided. 4c, the auxiliary bearing 11 is centered as described above and is welded and fixed to the support leg 12.
It enables smooth bearings.

[0027]

As described above, according to the present invention,
The support legs that support the sub-bearings are made of steel plate by cold plastic working, so they are obtained with high accuracy and in a short time, and are made of cast forging used in conventional fully hermetic electric compressors. Compared to the support leg that is inferior in material accuracy, machining can be omitted, expensive machining equipment and processing costs can be eliminated, and the mounting accuracy of the auxiliary bearing can be improved and the cost can be reduced.

Further, since the auxiliary bearing is centered with respect to the rotary shaft and is welded and fixed to the support leg, the case is formed by a combination of complicated related parts such as mounting the compressor body, the support leg and the like in the case. Even if the center of the rotary shaft is deviated from the center of the rotary shaft, the sub bearing acts as a smooth sliding bearing with respect to the rotary shaft, and noise from the sub bearing can be prevented.

Further, since the auxiliary bearing has a separate structure and not only slides on the rotating shaft but also a slidable portion is provided inside the auxiliary bearing, the rotating shaft is bent and deformed or the above-mentioned core is formed. Even if there is a slight error in the output, these can be absorbed by the respective sliding parts, and noise can be eliminated as a smooth slide bearing.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an embodiment of a totally hermetic electric compressor according to the present invention.

FIG. 2 is an exploded perspective view showing a specific example of a sub bearing in FIG.

FIG. 3 is a vertical cross-sectional view showing a specific example of an assembled state of the auxiliary bearing and its supporting leg in FIG.

FIG. 4 is a vertical cross-sectional view showing a specific example of a method of attaching the auxiliary bearing to the support leg in FIG.

[Explanation of symbols]

 1 Compressor Main Body 3 Main Bearing 4 Rotating Shaft 4c Secondary Shaft 5 Orbiting Scroll 6 Fixed Scroll 10 Electric Motor 11 Secondary Bearing 11a Spherical Bearing 11b Outer Ring 11c Inner Ring 12 Support Leg 12a Annular Wall 12a 12b Outer Diameter Side Flat 12c Inner Diameter Side Flat part 12d Hole 13 Airtight container 13a Case 15 Centering device 16 Welding torch 17 Temporary fixing jig

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Masanori Wakaizumi 800 Tomita, Ohira-cho, Shimotsuga-gun, Tochigi Hitachi Tochigi Plant (72) Inventor Mitsuaki Haneda 502 Kintate-cho, Tsuchiura-shi, Ibaraki Hitsuritsu Co., Ltd. (72) Inventor Keiji Taguchi 502, Kamidate-cho, Tsuchiura, Ibaraki Prefecture

Claims (4)

[Claims] 1. A compression mechanism part and an electric motor part are connected and stored by a rotary shaft in an airtight container formed by welding lids to the upper and lower sides of a cylindrical case, and the rotation is provided near the compression mechanism part. In a fully sealed electric compressor having a two-bearing structure, in which a main bearing of a shaft is arranged, and a sub-bearing of the rotary shaft is arranged so as to sandwich an electric motor part with the main bearing, an annular wall joined to an inner surface of the case. And a support plate made of a steel plate by plastic working, which has a flat portion extending from the annular wall to the inner diameter side of the case and having a hole through which the rotary shaft passes, and the support leg is The auxiliary bearing is fixed to the inner surface of the case by being press-fitted into the case and welded, and the flat portion of the support leg serves as a supporting portion of the auxiliary bearing, and the auxiliary bearing is centered and adjusted with respect to the rotating shaft. Fully sealed electric motor characterized by being welded and fixed to the flat portion of the supporting leg. Compressor. 2. The spherical bearing according to claim 1, wherein the sub bearing has an inner surface on which the rotary shaft is slidably fitted and a smooth spherical outer surface, and the outer surface of the spherical bearing slides on the spherical bearing. An outer ring having spherical inner surfaces that freely oppose each other, and an annular recess in a part of the inner surface, and a press-fit into the recess of the outer ring to slide on the outer surface of the spherical bearing. A hermetically sealed electric compressor comprising an inner ring having a spherical inner surface that freely opposes and slidably enclosing the spherical bearing by the outer ring and the inner ring. .. 3. The sub-bearing according to claim 1, wherein after the centering of the sub-bearing is adjusted, the annular wall of the support leg is fixed to the inner surface of the case, and the sub-bearing is fixed to the flat portion of the support leg by welding. A fully enclosed electric compressor characterized by: 4. The welding according to claim 3, wherein the case and the annular wall of the support leg are welded, and the flat portion of the support leg and the auxiliary bearing are provided with a plurality of dots using non-consumable electrodes. A fully hermetic electric compressor that is welded by welding.