JPH02248668A - Electric compressor - Google Patents

Abstract

PURPOSE:To reduce the cost, noise and vibration by pivotally supporting a ring mounted on the end ring outer circumference of a rotor or directly the end ring outer circumference of a rotor by an anti-machine part side bearing mounted on the core inner circumference of a stator. CONSTITUTION:A ring 14 mounted on the end ring outer circumference of a rotor 6 or the end ring outer circumference is pivotally supported by an anti-machine part side bearing 6 mounted on the core inner circumference of a stator 5. In the stator core, the laminated quantity of the core is increased in the thrust direction over the end surface of the rotor core by a necessary dimension, and this part is set as a bearing mounting part 5a in such a manner that the bearing 8 is faced to the ring 14. The materials of the bearing 8 and the ring 14 are selected in consideration with the reduction degree of electric motor performance by leakage of the electric motor magnetic flux and sliding performance. Hence, the whole length of the compressor can be shortened to reduce the number of parts, weight and the cost, and also the whirling of the rotor can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an electric compressor used in refrigeration and air conditioning equipment such as refrigerators, showcases, and air conditioners.

Conventional technology The conventional configuration will be explained using FIG. 3.

Reference numeral 1 denotes a hermetic casing, and 2 a mechanical part for compressing refrigerant. The mechanical part 2 is connected to an electric motor part 4 by a shaft 3.

6 and 6 are the stator and rotor of the electric motor section 4, and there is a rotor gap 7 between them, which is a minute space.

8 is a bearing that supports the shaft end 3a on the side opposite to the mechanical part;
Further, 9 is a housing in which the bearing 8 is mounted, and is fixed to the sealed casing 1.

1o and 11 are suction pipes and discharge pipes, and 12 is lubricating oil.

The operation of the electric compressor configured as above will be explained.

The low-pressure refrigerant gas introduced into the mechanical part 2 through the suction pipe 1o flows through the shaft 3 as the motor part 40 and the rotor 6 rotate.
When the mechanical part 2 performs a compression operation via the (not shown).

Further, the mechanical part 2 is lubricated by supplying lubricating oil /l/12 at the bottom of the closed casing 1 by an appropriate means (not shown).

Here, the size of the rotor gap 7 is a point that greatly affects motor performance, that is, compressor performance, and in a small capacity motor, it is necessary to set it to an extremely small gap.

However, due to processing accuracy and assembly accuracy, the stator 6
It is inevitable that there will be some degree of concentricity between the inner diameter of the rotor and the outer diameter of the rotor 6, and rotor gap discrepancies will occur as the shaft 3 and therefore the rotor 6 swing around due to compression action and centrifugal force. , and this rotor gap disparity is further enlarged by the magnetic attraction force.

As a result, noise, vibration, and input power due to rotor gap disparity increase, and furthermore, there are cases where the outer circumference of the rotor and the inner circumference of the stator come into contact.

Therefore, in view of the above, by supporting the shaft end 3a on the side opposite to the mechanical part with the bearing 8, the shaft 3 and the rotor 6
The structure was designed to prevent the rotor from wobbling and to prevent the rotor gap from widening.

Problems to be Solved by the Invention However, in the conventional configuration as described above, the space occupied by the bearing 8 on the side opposite to the mechanical part and the housing 9 is large, which increases the overall length of the compressor and increases the number of parts.
There were problems in that the weight increased and the cost also increased.

The present invention solves the above problems, and has a structure in which a ring attached to the outer circumference of the end ring of the rotor or the outer circumference of the end ring of the rotor is supported by a bearing on the side opposite to the mechanical part attached to the inner circumference of the core of the stator. The aim is to provide a compact, low-cost, and high-performance electric compressor.

Means for Solving the Problems The present invention has a structure in which a ring attached to the outer periphery of the end ring of the rotor or the outer periphery of the end ring is supported by a bearing on the side opposite to the mechanical part attached to the inner periphery of the core of the stator.

According to the above-described structure, the present invention has the bearing on the side opposite to the mechanical part built into the electric motor part, so there is no need for a housing for mounting the bearing and fixing it to the sealed casing as in the conventional case. The overall length of the compressor can be shortened, resulting in a compact structure that reduces the number of parts, weight, and cost. It also prevents the rotor from swinging around due to compression operation and centrifugal force, resulting in high performance with low noise and vibration. It is possible to provide an electric compressor.

Example Embodiments of the present invention will be described below with reference to FIG.

Note that the same parts as in the conventional example are given the same reference numerals, and detailed explanations are omitted.

The basic configuration and operation of the compressor are the same as before, but
The present invention has a structure in which a ring 14 attached to the outer circumference of the end ring of the rotor 6 or the outer circumference of the end ring is supported by a bearing 8 on the side opposite to the mechanical part attached to the inner circumference of the core of the stator 6.

In FIG. 1, after the winding process is completed, the bearing 8 is attached to a bearing attachment portion 6a on the inner circumference of the stator by means such as press-fitting or gluing.

At this time, the amount of stacked cores in the stator core is increased in the thrust direction by the required dimension on the end face of the rotor core, and the inner periphery of the stator in this area is used as the bearing mounting part 6a, and the bearing 8 is mounted on the outer periphery of the end ring 13. The ring 14 is set at a position opposite to the ring 14 that is formed.

Moreover, the core of the bearing mounting part 6a of the stator core is
The core may be punched out to have a slightly larger inner diameter than the core of the other portion, and may be formed by clamping it integrally with the core of the other portion to determine the installation space and thrust direction position of the bearing 8.

In addition, the core of the bearing mounting portion 6a may be made of a thicker iron plate than the core of other portions to increase the strength of the core against the bearing load.

On the other hand, a ring 14 is attached to the outer periphery of the end ring 13 by shrink fitting, press fitting, adhesive, or the like, and the outer periphery is supported by the bearing 8.

Here, materials for the bearing 8 and the ring 14 may be appropriately selected in consideration of the degree of deterioration of motor performance due to leakage of motor magnetic flux, sliding performance, etc.

Furthermore, since the bearing 8 on the non-mechanical part side is built into the electric motor part 4, the span between the bearing 8 on the non-mechanical part side and the bearing part (not shown) in the mechanical part 2 is shorter than in the past. Therefore, the concentricity between the inner circumference of the stator and the outer circumference of the rotor is improved, and the amount of deflection due to the compression operation and centrifugal force of the shaft 3 is also reduced, so it is possible to reduce the setting of the rotor gap 7 and improve the motor performance. Moreover, it is possible to compensate for a decrease in motor performance due to the bearing 8 being built into the motor section 4.

In order to lubricate the bearing 8, a refrigerant passage is formed to intensively pass the refrigerant gas containing oil compressed and discharged from the mechanical part 2 into the rotor gap 7, and the oil mist is transferred to the bearing 8.
This is done by guiding it to the sliding part of the

Next, FIG. 2 shows another embodiment, in which the ring 14 in FIG. 1 is omitted and the outer periphery of the end ring 13 is brought into direct contact with the inner periphery of the bearing 8.

It is also possible to adopt a method of applying

By arranging the bearing support section on the side opposite to the mechanical section configured as described above, it is possible to achieve a structure that is more compact and lower cost than the conventional structure, and also reduces the swinging of the rotor due to compression action and centrifugal force action. It is possible to provide a high-performance electric compressor with low noise and low vibration.

Effects of the Invention As is clear from the above description, the present invention provides a ring attached to the outer periphery of the end ring of the rotor, or the outer periphery of the end ring of the rotor is directly supported by a bearing on the side opposite to the mechanical part attached to the inner periphery of the core of the stator. Compact and low cost,
Furthermore, it is possible to provide a high-performance electric compressor with low noise and low vibration.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of an electric compressor showing an embodiment of the present invention;
FIG. 2 is a longitudinal sectional view showing another embodiment corresponding to FIG. 1, and FIG. 3 is a longitudinal sectional view of a conventional electric compressor. 1... Sealed casing, 2... Mechanical part, 3... Shaft, 4... Electric motor part,
6... Stator, 6... Rotor, 8...
...Bearing on the side opposite to the mechanical part, 13 ... End ring, 14 ... Ring. Name of agent: Patent attorney Shigetaka Awano and one other figure! --- 2-・ 4-・ 5-・- 6-・ 8-・- Rebuttal to the mechanical department shaft electric vlh capital stator loader? 11 ffi 111 Mri I4-...Link diagram d

Claims (2)

[Claims] (1) A mechanical part and an electric motor part connected to this with a shaft are built into a sealed casing, and the ring attached to the outer periphery of the rotor end ring of the motor part is attached to the inner periphery of the stator core on the opposite side of the mechanical part. An electric compressor supported by bearings. (2) A mechanical part and an electric motor part connected to the mechanical part by a shaft are built into the sealed casing, and the outer periphery of the end ring of the electric compressor rotor is supported by a bearing on the side opposite to the mechanical part attached to the inner periphery of the stator core. Electric compressor.