JPH03194186A - Rotary compressor - Google Patents

Abstract

PURPOSE:To suppress vibration by making a rotary compressor in such a construction that the rotary shaft of a motor for driving the compressing device accommodated in a sealed case is borne by an upper and a lower bearing of the compressing device, and therein furnishing the stator of the motor with a ring-shaped bearing bracket, and supporting the bracket with a third bearing. CONSTITUTION:A motor 2 installed in the upper part of a sealed case 1 is composed of a stator 3 fixed to the inner wall of the sealed case 1 and a rotor 5 accommodated inside of the stator with a gas reserved and rotating as in a single piece with a rotary shaft 4, and a compressing device 8 is driven with rotation of the rotary shaft 4. This rotary shaft 4 is supported rotatably by No.1 and No.2 bearing 9, 10 at an upper and a lower point of the compressing chamber of the compressing device 8. Therein the top of the rotary shaft 4 is protruded up above the oversurface of the rotor 5, and the top is supported rotatably by a third bearing 11. This third bearing 11 is formed dividedly consisting of a ring-shaped bearing bracket 12 fixed to the stator 3 and a bearing 13 fixed to this bearing bracket 12.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a rotary compressor used in an air conditioner, etc.
More specifically, the present invention relates to a structure for further reducing vibrations generated during high-speed rotation.

[Prior Art] As shown in FIG. 3, a rotary compressor has a motor 22 disposed in the upper part of a sealed case 21, and a compression device in the lower part that compresses refrigerant as the motor 22 rotates. A device 23 is provided, and the rotating shaft 24 of the motor 22 is rotatably supported by a first bearing 25 and a second bearing 26 provided at the upper and lower portions of the compression device 23. In order to cancel the unbalance of the shaft piston part (not shown) in the compression device 23, the rotating shaft 2
An upper balancer 28 and a lower balancer 29 are attached to a rotor 27 fixed to the rotor 4.

However, during high-speed rotation under inverter control, the centrifugal force of the upper balancer 28 increases, bending and deforming the rotating shaft 24, causing a problem in which the rotor 27 comes into contact with the stator 30.

As a countermeasure, the weight of the upper balancer 28 is made lighter than necessary for balance to reduce bending and deformation of the rotating shaft 24.

[Problem to be solved by the invention]

However, as mentioned above, in order to reduce the bending deformation of the rotating shaft during high-speed rotation, if the weight of the upper balancer is made lighter than the weight necessary for balance, the rotation of the rotating shaft becomes unbalanced, causing vibration. Become the source.

Further, in order to ensure mechanical safety even if the above-mentioned bending deformation occurs, it is necessary to use a highly rigid and expensive material for the rotating shaft.

Therefore, an object of the present invention is to solve these problems and provide a rotary compressor that can further reduce bending and deformation of the rotating shaft even during high-speed rotation.

[Means to solve the problem]

The present invention has been made to solve the above-mentioned problems, and includes a motor disposed in the upper part of a sealed case, a compression device for compressing refrigerant as the motor rotates in the lower part, and the motor In a rotary compressor, a rotary shaft of the motor is rotatably supported by first and second bearings formed at an upper and a lower portion of the compression device, the rotary shaft of the motor is
A ring-shaped bearing bracket that protrudes from the upper surface of the rotor fixed to the rotary shaft, is fixed to the stator of the motor, and is parallel to the upper surface of the stator, and a bearing fixed to the same bearing bracket. A third bearing is provided, and the protruding rotating shaft is rotatably supported by the third bearing.

[Effect]

With the above configuration, the upper end of the rotating shaft can be rotatably supported by the third bearing, so that wobbling of the rotating shaft can be suppressed and bending deformation of the rotating shaft can be prevented.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on FIGS. 1 and 2.

FIG. 1 is a vertical side view schematically showing the internal structure of a rotary compressor, in which 1 is a closed case, 2 is a motor disposed in the upper part of the closed case 1, and a stator 3 that constitutes the motor 2. is fixed to the inner wall of the sealed case 1, and an upper balancer 6 and a lower balancer 7 are attached to a rotor 5 fixed to a rotating shaft 4.

Reference numeral 8 denotes a compression device disposed at the lower part of the sealed case 1. The outer periphery of the compression device 8 is fixed to the inner wall of the sealed case 1, and a compressor is provided inside to compress the refrigerant as the motor 2 rotates. A first bearing 9 rotatably supports the rotating shaft 4 of the motor 2 above and below the compression chamber.
and a second bearing 10.

Incidentally, the upper end of the rotating shaft 4 is provided to protrude higher than the upper surface of the rotor 5 fixed to the rotating shaft 4, and the protruding rotating shaft 4 is rotatably supported by a third bearing 11. ing.

As shown in FIG. 2, the third bearing 11 is divided into a bearing bracket 12 fixed to the stator 3 of the motor 2 and a bearing 13 fixed to the bearing bracket 12.

The bearing bracket I2 is made of iron or the like, and has a plurality of mounting feet 12a fixed to the stator 3 on the outer periphery of a ring-shaped disc, screw holes 12b on the inner periphery of the disc, and screw holes 12b on the outer periphery. A plurality of holes 1.2c are provided for passing compressed refrigerant gas, etc., and the mounting legs 12a are fixed to cutouts 3a formed on the outer peripheral surface of the stator 3 by welding or the like.

On the other hand, the bearing 13 is cast from iron (sintered alloy, etc.), has a bearing part 13a in the center of the disc, and has a plurality of screw holes provided near the inner periphery of the bearing bracket 12 near the outer periphery. A hole 13b corresponding to the hole 12b and a hole 13c for passing compressed refrigerant gas etc. are provided, and a screw 14 is inserted into the hole 13b,
A rotating shaft 4 of the motor 2 is fixed so as to be rotatable.

[Effects of the Invention] As described above, if the compressor is equipped with the third bearing, vibration of the rotating shaft is suppressed and bending deformation of the rotating shaft is reduced, so even during high-speed rotation. Large vibrations are no longer generated, and as the above-mentioned point deformation is reduced, there is no need to use highly rigid and expensive materials, and since the above-mentioned bearing has a two-piece structure, Assembly is easy, and mechanical precision can be easily improved.

[Brief explanation of drawings]

Fig. 1 is a vertical side view of a rotary compressor showing an embodiment of the present invention, Fig. 2 is a perspective view of essential parts of the same embodiment, and Fig. 3 is a longitudinal side view of a rotary compressor showing a conventional example. It is. In the figure, ], - closed case, 2 - motor, 3 - stator, 3
a - notch, 4 - rotating shaft, 5 - rotor, 6 - upper balancer, 7 - lower balancer, 8 - compression device, 9 - first bearing, 10 - second bearing, 11 - third bearing , 12-Bearing bracket, 12a-Mounting foot, 12b-Screw hole, 12c
M hole, 13-bearing, 13a-bearing @ 13b---hole,
13c - hole, 14 - screw.

Claims (1)

[Claims] A motor is disposed in the upper part of the airtight case, a compression device is disposed in the lower part that compresses the refrigerant as the motor rotates, and the rotating shaft of the motor is connected to a first motor formed at the upper and lower parts of the compressor. and a rotary compressor rotatably supported by a second bearing, the rotary shaft of the motor protruding from the upper surface of the rotor fixed to the rotary shaft;
A third bearing is provided, which is fixed to the stator of the motor and includes a ring-shaped bearing bracket parallel to the upper surface of the stator, and a bearing fixed to the bearing bracket.
A rotary compressor, characterized in that the protruding rotating shaft is rotatably supported by a bearing.