Motor-driven compressor

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to an electric compressor having a motor driven by receiving power supply from a battery or the like. This type of electric compressor can be used as a compressor for compressing a refrigerant in an in-vehicle air conditioner.

【0002】

[Conventional technology]

For example, Japanese Patent Application Laid-Open No. 8-105392 describes an electric compressor in which a gas compression unit, an electric motor, and a shaft for transmitting the driving force of the motor to the gas compression unit are built in a closed container. It is disclosed. In the electric compressor, a cylindrical boss portion for accommodating a bearing bearing one end of a shaft is provided in a closed container. As a result, the shaft bearings are arranged in a closed space.

【0003】

[Problems to be Solved by the Invention]

If the bearing of the shaft is arranged in the closed space as described above, the lubrication of the bearing may be insufficient.

【0004】

Therefore, an object of the present invention is to provide an electric compressor having improved lubricity of a shaft bearing.

【0005】

Another object of the present invention is to provide an electric compressor having improved heat dissipation when a heat radiating fin is provided adjacent to a tubular boss portion accommodating a shaft bearing.

【0006】

[Means for solving problems]

According to the present invention, a gas compression unit, an electric motor, and a shaft for transmitting the driving force of the motor to the gas compression unit are built in a closed container, and the closed container receives one end of the shaft. In an electric compressor having a tubular boss portion supported via the above, an electric compressor characterized by providing holes penetrating inside and outside on the peripheral wall of the tubular boss portion can be obtained.

【0007】

The closed container may have a suction port for sucking gas at a position radially opposed to the hole.

【0008】

The hole axis of the hole may extend diagonally with respect to the axial direction.

【0009】

A heat radiation fin may be provided adjacent to the tubular boss portion.

【0010】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

【0011】

FIG. 1 is a vertical cross-sectional view showing an electric compressor according to the first embodiment of the present invention. The electric compressor of FIG. 1 includes a discharge housing 11, an intermediate housing 12, and a suction housing 13. The discharge housing 11, the intermediate housing 12, and the suction housing 13 are all made of a metal material and are connected to each other by bolts 14a and 14b to form a closed container 15.

【0012】

The discharge housing 11 is provided with a discharge port 16 on the end surface. A fixed scroll member 17 fixed to the discharge housing 11 and a movable scroll member 18 facing the fixed scroll member 17 are arranged in the discharge housing 11, and the gas refrigerant is compressed by these fixed and movable scroll members 17, 18. The gas compression unit 19 is configured.

【0013】

The fixed scroll member 17 includes a bottom plate 21, a spiral body 22 provided on one surface of the bottom plate 21, and a fixing portion 23 provided on the other surface of the bottom plate 21. The fixing portion 23 is fixed to the end wall of the discharge housing 11 by a screw 24.

【0014】

The movable scroll member 18 includes a bottom plate 26, a spiral body 27 provided on one surface of the bottom plate 26, and a boss portion 28 cylindrically protruding from the other surface side of the bottom plate 27. A rotation blocking mechanism 29 composed of an EM coupling that prevents the movable scroll member 18 from rotating and enables turning motion is provided between the bottom plate 26 surface around the boss portion 28 and one end of the intermediate housing 12. There is.

【0015】

A shaft 31 extending from the inside of the intermediate housing 12 to the inside of the suction housing 13 is provided. One end 31a of the shaft 31 is supported inside a tubular boss portion 33 protruding from the end wall 32 of the suction housing 13 toward the compression portion 19 side via a rolling bearing 34.

【0016】

The motor (electric part) 35 is provided in the stator 36 provided on the inner wall portion of the intermediate housing 12 and the suction housing 13, the coil 37 provided around the stator 36, and the stator 36 provided around the shaft 31. It is provided with a rotor 38 fixed to the shaft 31.

【0017】

A large diameter portion 31b is provided at the other end of the shaft 31, and is supported in the intermediate housing 12 via a rolling bearing 39. An eccentric pin 31c is provided so as to project from the end of the large diameter portion 31b. The eccentric pin 31c is inserted into the eccentric bush 42 supported by the boss portion 28 via the bearing 41.

【0018】

The above configuration is almost the same as that of the electric compressor according to the prior art.

【0019】

In the electric compressor of FIG. 1, a suction port 43 for sucking the refrigerant gas into the closed container 15 is further provided on the peripheral wall 44 of the suction housing 13. On the other hand, on the peripheral wall of the tubular boss portion 33, a hole 45 penetrating inside and outside is formed at a position facing the suction port 43 in the radial direction. The formation of the hole 45 is easily possible by inserting a tool such as a drill through the suction port 43. The axial position of the hole 45 is selected closer to the root of the tubular boss portion 33 than to the rolling bearing 34.

【0020】

During operation of this electric compressor, the refrigerant gas flows into the suction housing 13 through the suction port 43. At that time, since the refrigerant gas actively flows into the tubular boss portion 33 through the hole 45 facing the suction port 43, the lubricating oil contained in the refrigerant gas is supplied to the rolling bearing 34, which is preferably lubricated. To do. The refrigerant gas that has flowed into the suction housing 13 further flows into the intermediate housing 12 through a gap between the stator 36 and the rotor 38 of the motor 35 and a gas passage (not shown) provided on the outer peripheral portion of the stator 36. Further, the refrigerant gas flows into the inside of the discharge housing 11 through the gap of the rolling bearing 39, reaches the periphery of the gas compression unit 19 through the gap of the rotation blocking mechanism 29, and is taken into the gas compression unit 19. When the refrigerant gas passes through the rolling bearing 39 and the rotation blocking mechanism 29, the lubricating oil contained in the refrigerant gas is supplied to the rolling bearing 39 and the rotation blocking mechanism 29 to lubricate them.

【0021】

FIG. 2 is a vertical sectional view showing an electric compressor according to a second embodiment of the present invention. Similar parts are designated by the same reference numerals and the description thereof will be omitted.

【0022】

In the electric compressor of FIG. 2, the hole shaft of the hole 45 formed in the tubular boss portion 33 extends obliquely in the direction of the axial center of the shaft 31, that is, in the axial direction. Moreover, the inclination angle of the hole shaft with respect to the axial direction is selected so that the hole shaft of the hole 45 does not come into contact with the edge portion 13a of the suction housing 13. The inclined hole 45 can be easily formed by applying a tool such as a drill without touching the edge portion 13a of the suction housing 13.

【0023】

Also in this electric compressor, during operation, the refrigerant gas flows into the suction housing 13 through the suction port 43, and further flows into the tubular boss portion 33 through the hole 45, so that the lubricating oil contained in the refrigerant gas Is supplied to the rolling bearing 34, which is preferably lubricated.

【0024】

Although the holes 45 are formed on the lower surface of the tubular boss portion 33, they may be formed on the upper surface or the lateral surface, and the number thereof can be arbitrarily changed.

【0025】

FIG. 3 is a vertical sectional view showing an electric compressor according to a second embodiment of the present invention. Similar parts are designated by the same reference numerals and the description thereof will be omitted.

【0026】

The electric compressor of FIG. 3 is provided with a drive circuit 46 on the side of the end wall 32 of the suction housing 13 opposite to the tubular boss portion 33. This drive circuit 46 drives the motor 35 and generates heat. Therefore, in order to promote heat dissipation by the suction refrigerant gas having a relatively low temperature, the end wall 32 is provided with a plurality of heat radiation fins 47 adjacent to the tubular boss portion 33. In the illustrated example, one (or a plurality) of the heat radiation fins 47 is also provided inside the tubular boss portion 33. The hole shaft of the hole 45 formed in the tubular boss portion 33 extends obliquely with respect to the axial direction so as not to hit the edge portion 13a of the suction housing 13 or the heat radiation fin 47.

【0027】

Also in this electric compressor, during operation, the refrigerant gas flows into the suction housing 13 through the suction port 43, and further flows into the tubular boss portion 33 through the hole 45, so that the lubricating oil contained in the refrigerant gas Is supplied to the rolling bearing 34, which is preferably lubricated. Further, since the heat dissipation of the heat radiating fins 47 provided inside the tubular boss portion 33 is also promoted by the refrigerant gas, the heat transfer area can be widened and the cooling capacity can be improved.

【0028】

Although the holes 45 are formed on the lower surface of the tubular boss portion 33, they may be formed on the upper surface or the lateral surface, and the number thereof can be arbitrarily changed.

【0029】

[Effect of the invention]

As described above, according to the present invention, it is possible to provide an electric compressor having improved lubricity of a shaft bearing. In addition, heat dissipation is also improved when heat dissipation fins are provided adjacent to the tubular boss portion accommodating the shaft bearing.

[Simple explanation of drawings]

[Figure 1]

It is a vertical sectional view which shows the electric compressor which concerns on 1st Embodiment of this invention.

[Figure 2]

It is a vertical sectional view which shows the electric compressor which concerns on 2nd Embodiment of this invention.

[Fig. 3]

It is a vertical sectional view which shows the electric compressor which concerns on 3rd Embodiment of this invention.

[Explanation of symbols]

11 Discharge housing 12 Intermediate housing 13 Inhalation housing 15 Closed container 16 Discharge port 17 Fixed scroll member 18 Movable scroll member 19 Gas compression unit 29 Rotation blocking mechanism 31 shaft 32 end wall 33 Cylindrical boss 34 Rolling bearing 35 motor (electric part) 36 stator 37 coil 38 rotor 39 Rolling bearing 41 Bearing 42 Eccentric bush 43 Inhalation port 44 perimeter wall 45 holes 46 Drive circuit 47 Heat dissipation fins