JPH0260443A - Centering device for motor of electrically driven compressor - Google Patents

Abstract

PURPOSE:To make it possible to check center and alignment with high precision by contracting and expanding collets with slide sections moved in the condition where the collets are inserted between the inside diameter of a stator and the outside diameter of a rotating shaft. CONSTITUTION:A centering device 21 is inserted under the condition where there is a suitable void 28 between the internal surface 24a of an inside collet 24 and the external surface 1a of a rotating shaft 1 and between the internal surface 2a of a stator 2 and the external surface 25a of an outside collet 25. With a slide section 22 moved upwards the inside collet 24 is contracted and outside collet 25 is expanded. The slide section 22 is collet-shaped of which plural grooves are furrowed from a taper 28a formation side to upward and is furnished with elastic function. The slide section itself will actuate, following the taper section 22a of the collet and is of a structure allowing it to absorb the difference in void dimension between the inside and outside diameters. The concentric precision can thereby be improved between the shaft center of the rotating shaft 1 and that of the stator 2.

Description

[Detailed Description of the Invention] [Field of Application in Industry-1-] The present invention relates to a motor centering device for an electric compressor, and in particular, the present invention relates to a motor centering device for an electric compressor. The present invention relates to a centering device suitable for obtaining a uniform air gap between an electric motor rotor directly connected to a shaft and the stator.

[Conventional technology]

A conventional centering device will be explained with reference to FIGS. 3 and 4. 3M is a vertical cross-sectional view of the main part of the centering device with the sliding part's movement device omitted, and FIG. 4 is a perspective view of the collet. In the figure, the outer diameter of the rotating shaft 1 and the blade hole provided at the center of the centering device 11 are loosely connected, the sliding portion 12 of the centering device 11 is slid 1-, and the taper of the fixed portion 13 is Face 13
The collet 14 inserted between the tapered surface 12b of the slide portion 12 facing the a is expanded toward the inner diameter side of the stator 2, and by bringing the collet into close contact with the collet 14, the center of the rotating shaft 1 and the center of the stator 2 is aligned. It is. 3 is a frame, and 4 is a bolt. The left half of the broken line A-A in FIG. 3 shows the state before the collet is expanded, and the right half shows the collet in the expanded state.

Furthermore, as shown in FIG. 4, the shape of the collet 14 is thin as a whole in order to exhibit an elastic function, and has slits 14a, 14. b has been applied.

[Problem to be solved by the invention]

The conventional device described above does not take centering into consideration to obtain high centering accuracy. That is, a gap 1a necessary for smooth insertion is required between the outer diameter of the rotating shaft 1 and the guide hole 12a of the slide portion 12, and this gap 1a causes variations in centering accuracy. . In addition, since there is a gap between the fixed part 13 and the sliding part 12 within a sliding range,
This gap could also cause variations in centering accuracy. Furthermore, when the collet is expanded, the slit causes deformation as shown by the broken line, and there is a possibility that the surface of the collet 14 does not come into close contact with the entire inner diameter of the stator 2.

If they do not come into close contact, it will be impossible to position the stator 2 over its entire thickness, and there is a possibility that the collet will be damaged due to insufficient strength.

An object of the present invention is to provide a motor centering device for an electric compressor that is capable of highly accurate centering.

[Means for Solving the Problems] The above object includes: - a plurality of inner collets that are in contact with the outer diameter of a rotating shaft that constitutes a part of an electric compressor; a plurality of outer collets that contact the inner diameter of the stator disposed on the outer periphery; a locking portion that locks both of the collets to the device main body; a tapered portion formed on the outside and inside of the two collets I; and a sliding part provided with a tapered part and an inclined part that coincides with the collet, and the collets are inserted between the inner diameter of the stator and the outer diameter of the rotating shaft, and the collet is contracted by moving the sliding part. This is achieved by expanding.

[Effect]

In the centering device according to the present invention, the elastic part of the collet that grips the outer diameter of the two rotating shafts and the inner diameter of the stator is made of a spring steel plate in order to increase the flexibility range. A slide portion having an inclined portion that connects with the tapered surface of each of the collets is inserted between the inner collet that contacts the rotating shaft and the outer collet that contacts the motor stator.

A plurality of slits are formed in this sliding portion to add elasticity. As a result, by moving the slide part, the inner collet contracts due to the action of the inclined part.

In addition, the outer collet expands, and the gap difference between the collet contact surface and the contact surface (rotating shaft outer diameter, stator inner diameter) can be evenly adjusted by elastic deformation of the slide collet, ensuring reliable Highly accurate centering operation is possible.

〔Example〕

Two embodiments of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 is a vertical cross-sectional view of the main part of the centering device, omitting the immediate action device for driving the pulling section, and FIG. 2 is a cross-sectional view taken along the line CC in FIG. 1. In the figure, 1 is the rotating shaft, 2 is the stator of the electric motor, and 3 is the frame.

4 is a bolt. The rotating shaft 1 is inserted into the inner diameter of the main bearing portion a of the frame 3. The stator 2 is fixed to the mounting surface 3b of the frame 3 by the poles 1-4 after centering by the centering device 21.

21 is the above-mentioned centering device. In FIG. 1, the left half of the broken line BB shows the inserted state of the centering device, and the right half shows the contracted and expanded states of each collet. The centering device 21
has a slide part 22 in the center, and the slide part 2
Opposing tapered surfaces 22a are formed on the lower side of the slider 2, and the upper portion thereof is fixed to the slide pull-up portion 23. 24 is an inner collet, and 25 is an outer cholera l~. The collets 24 and 25 are connected to the pulling section 2 through steel plates 26, respectively.
3 is elastically supported by a fixing part 27 that includes the holder 3.

The centering device 21 consists of two parts, as shown on the left half of the dashed line B-B, between the inner diameter 24a of the inner collet 24 and the outer diameter 18 of the rotating shaft 1, and between the inner diameter 2a of the stator 2 and the outer collet 25. It is inserted with an appropriate gap 28 between the outer diameters 25a of the two. Such a centering device 21 is indicated by the broken line B-B in FIG.
As shown in the right half of the figure, as the slide portion 22 moves upward, the inner collet 24 contracts and the outer collet 25 expands. Therefore, the outer diameter 1a of the rotating shaft 1 and the inner diameter 2a of the stator 2 are held. At this time, it is impossible to make the gaps 28 uniform on both the inner and outer diameter sides, so the slide stops rising when one of the gaps 28 disappears, and the other gap remains, making it impossible to securely grip the slide. Can not. Therefore, as shown in FIG. 2 showing a cross-sectional view of the centering device, the taper 22 of the slide portion 22
Collen 1 with a plurality of grooves 22a carved upward from the a-forming side
The sliding part 22 itself is a centering device that operates while following the collet's taper part 22a, and has a structure that can absorb the gap dimension difference between the inner and outer diameters.

〔Effect of the invention〕

According to the present invention, the play gap between the two rotating shafts and the inner diameter of the slide part and the gap between the fixed part and the slide each caused variations in centering accuracy.

By moving the tapered parts of the outer collet and the slide part, the inner and outer diameters can be tracked with high precision, and the inner and outer diameters can be reliably gripped. I can figure it out.

Also, the inner and outer collets are divided into multiple pieces.

It is supported by a highly flexible spring steel plate, compared to the one-piece collet used in conventional centering devices.

Instability in centering accuracy due to unbalanced deformation is eliminated, and important factors leading to breakage are completely eliminated.

As mentioned above, the centering device according to the present invention corrects the drawbacks of accuracy and strength, stabilizes the centering of individual stators of electric compressors assembled in mass production, and finally improves the stability of the stators. The air gap between the rotor and the rotor (not shown) directly connected to the rotating shaft is made uniform, leading to improved performance.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a main part of a centering device according to an embodiment of the present invention;
FIG. 2 is a sectional view taken along the line C-C in FIG. 1, FIG. 3 is a vertical sectional view of a main part of a conventional centering device, and FIG. 4 is a perspective view of a collet used in the centering device shown in FIG. 3. . 1. Rotating shaft, la...Rotating shaft outer diameter, 2. Motor stator,
2a: Inner diameter of stator, 3: Frame, 3a: Main bearing of frame, 3b Stator mounting surface of frame,
4... Bolt, 21 Centering device, 22 Slide part, 22
a...Tapered part of the slide part. 23. Slide pulling part, 24. Inner collet. 24a... Inner diameter of the inner collet, 25... Outer collet, 25a - Outer diameter of the outer collet, 26 - Spring steel plate,
27・Fixed part.

Claims (1)

[Claims] 1. A plurality of inner collets in contact with the outer diameter of a rotating shaft forming a part of an electric compressor and forming a part of the electric motor,
a plurality of outer collets that contact the inner diameter of the stator disposed on the outer periphery of the rotating shaft; a locking portion that locks both the collets to the device main body; and a tapered portion formed on the outside and inside of the collets. , and a sliding part provided with an inclined part that coincides with the tapered part, and both collets are inserted between the inner diameter of the stator and the outer diameter of the rotating shaft, and the collets are moved by moving the sliding part. A motor centering device for an electric compressor that is characterized by contraction and expansion.