JPH09177687A - Motor-driven fluid machinery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the accuracy of upper and lower bearings to reliability by fixing an upper housing in a sealed casing, fixing a stator of a motor in the motor housing through a spigot fitting part, and press-fitting and fixing a lower housing into the stator. SOLUTION: An upper housing 3 having an upper nearing 31 to support an upper part of a drive shaft 5 of a motor 4 is fixed to the inside of a sealed casing 1, a stator 41 of the motor 4 is fixed to the upper housing 3 through a spigot fitting part 32, and a lower housing 6 having a lower bearing 61 to support a lower part of the drive shaft 5 is press-fitted and fixed to the stator 41. The stator 41 can be integrated with the lower housing 6 without clearance through the press fit, the axis of the stator 41 can be aligned with the axis of the lower bearing 61 of the lower housing 6 without clearance, and the deviation in the alignment between the axis of the stator 41 and the axis of the lower bearing 61 of the lower housing 6 can be eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric fluid machine having a motor inside.

[0002]

2. Description of the Related Art Conventionally, a motor having a rotor and a stator having a drive shaft is housed in a closed casing, and the stator of the motor is fixed to the casing and an upper bearing for supporting the upper part of the drive shaft is provided. An upper housing with
An electric fluid machine in which a lower housing having a lower bearing for supporting a lower portion of the drive shaft is fitted with a spigot and fixed integrally by bolting is, for example, an actual open flat 1-1495.
No. 84 publication.

That is, as shown in FIG. 3, an electric fluid machine having a conventional motor has a motor C having a compression element B in an upper inner part of a hermetic casing A and a stator D and a rotor E in a lower inner part thereof. And an upper bearing G for supporting the upper part of the drive shaft F of the motor C in the casing A.
The upper housing H having a fixed shape, the upper housing H supporting the compression element B, and the motor C
A lower housing K having a lower bearing J for supporting the lower portion of the drive shaft F of the motor C is provided below the.

Then, the stator D of the motor C is fitted in the upper housing H and the lower housing K by spigot fitting, and the stator D is clamped between the upper housing H and the lower housing K by bolts L to be integrated. It is fixed to.

[0005]

However, in order to fit the stator D to the upper housing H and the lower housing K by the spigot fitting, that is, the lower housing K is fixed to the upper housing H via the stator D. Therefore, the axial center of the lower bearing J of the lower housing K is likely to deviate from the axial center of the upper bearing G of the upper housing H by the amount of the gap in each spigot portion, and this misalignment deteriorates the coaxiality. In order to reduce this deviation, it is necessary to make the gap in the spigot portion as small as possible, which makes the gap management complicated.

If the squareness of the abutment surface of the stator D and the bearing surfaces of the bearings G and J in each spigot portion is not accurate, the motor C and the lower housing K are inclined with respect to the upper bearing G, The drive shaft F and the lower bearing J are tilted in the axial center.

Further, since the upper housing H, the stator D, and the lower housing K are tightened through the bolts L in a penetrating manner, if there is a variation in tightening, the motor C and the lower housing K are tilted, and the drive shaft F is also. And lower bearing J
The axis of is tilted.

Moreover, as shown in FIG. 3, the air gap P of the motor C is passed through the suction passage N forming the fluid introduced from the suction pipe M into the casing A in the lower housing K.
When the shaft center deviation occurs when passing through the air passage, the size of the air gap P varies, and the flow resistance in the passage also varies, so that the passage cannot be designed accurately by controlling the suction flow rate. There is also.

The present invention was invented to solve the above problems, and one of the objects thereof is to provide an electric fluid machine which improves the accuracy of coaxiality between the upper bearing and the lower bearing to improve reliability. Another object of the present invention is to facilitate the design of the passage by controlling the suction flow rate.

[0010]

According to the first aspect of the present invention,
In the closed casing 1, an upper housing 3 having an upper bearing 31 that supports the upper portion of the drive shaft 5 of the motor 4 is fixed,
The stator 41 of the motor 4 is fixed to the upper housing 3 via the spigot fitting portion 32, and the lower housing 6 having the lower bearing 61 that supports the lower portion of the drive shaft 5 is press-fitted into the stator 41. It was fixed.

With the above construction, in the invention according to claim 1, since the stator 41 and the lower housing 6 are integrated by press fitting without a gap, the axial center of the stator 41 and the lower bearing 61 of the lower housing 6 are integrated. Since the axes can be aligned with each other without a gap, and the axis deviation between the axis of the stator 41 and the axis of the lower bearing 61 of the lower housing 6 can be eliminated, and as a result, the upper housing 3 The shaft bearing of the upper bearing 31 and the lower bearing 61 of the lower housing 6
The accuracy of coaxiality with the shaft center of is improved and reliability is improved.

Further, since the lower housing 6 is only fixed to the stator 41 by press fitting, it is possible to form the lower housing 6 with a light-weight sheet metal, which facilitates weight reduction design.

Further, since the deviation of the axial center is reduced, the variation in the air gap of the motor 4 is reduced, and the axial center as in the case of the conventional spigot fitting is obtained by press fitting between the lower housing 6 and the stator 41. Since there is no gap that causes deviation, passage design can be easily performed by controlling the suction flow rate.

According to a second aspect of the invention, in the first aspect of the invention, the stator 41 of the motor 4 is fixed to the upper housing 3 with bolts 33.

According to the second aspect of the present invention, the stator 41, to which the lower housing 6 is fixed by press-fitting, can be firmly fixed to the upper housing 3 by the above structure.
The coaxial accuracy between the axis of the upper bearing 31 of the upper housing 3 and the axis of the lower bearing 61 of the lower housing 6 is improved.

According to a third aspect of the present invention, in the first or second aspect of the invention, the stator 4 of the motor 4 is
The working fluid passage 44 is formed between 1 and the lower housing 6.

The working fluid passage 44 has a core cut portion formed on the outer peripheral portion of the stator 41, and when the lower housing 6 is press-fitted into the stator 41, the core cut surface and the inner peripheral surface of the lower housing 6 are separated from each other. It can be formed by the gap formed in.

With the above structure, in the invention according to the third aspect, the working fluid passage 44 having a desired passage resistance can be easily formed by press-fitting it into the stator 41 of the lower housing 6, and always has a constant passage area. Since the working fluid passage 44 can be formed, it is possible to suppress the variation in passage resistance due to the deviation of the axis as in the conventional case, and it is possible to easily design the passage by controlling the suction flow rate.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of an electric fluid machine according to the present invention will be described below with reference to FIGS. The embodiment is a scroll-type electric fluid machine, in which a fixed scroll 2 is provided above an inside of an airtight closed casing 1.
1 and a scroll element 22 composed of a movable scroll 22
The movable scroll 22 is supported by the upper housing 3, and a motor 4 including a stator 41 and a rotor 42 is disposed below the upper housing 3.

The stator 41 of the motor 4 is fitted into the spigot fitting portion 32 of the upper housing 3 and is fitted with a bolt 33.
The upper part of the drive shaft 5 of the motor 4 is supported by the upper bearing 31 of the upper housing 3, and the lower part of the drive shaft 5 is supported by the lower bearing 61 of the lower housing 6 fixed to the stator 41. I am letting you.

Further, the inside of the closed casing 1 is partitioned by the fixed scroll 21 into a discharge chamber 11 above the fixed scroll 21 and a low-pressure side chamber 12 below the fixed scroll 21, and the fixed scroll 21 is provided in the discharge chamber 11. The discharge port 23 and the external discharge pipe 7 are opened, while the suction pipe 8 is opened in the low pressure side chamber 12.

The upper portion of the drive shaft 5 is connected to the movable scroll 22, and the drive shaft 5 driven by the motor 4 is connected.
The movable scroll 22 is revolved with respect to the fixed scroll 21 by the rotational driving, and the refrigerant in the low-pressure side chamber 12 is introduced into the compression chamber between the fixed scroll 21 and the movable scroll 22 for compression, and the discharge port 23 Is discharged from the discharge chamber 11.

Further, an oil supply passage 51 extending in the axial direction is formed inside the drive shaft 5, and the oil supply passage 51 is formed.
An oil pump 52 is attached to the lower portion of the casing 1, the oil pump 52 is exposed to the bottom oil sump 13 provided at the bottom of the casing 1, and the lubricating oil pumped up from the bottom oil sump 13 via the oil supply passage 51 is The drive shaft 5 such as each bearing 31, 61
It is designed to lubricate the sliding parts of.

Further, the lower housing 6 has a bottomed cylindrical shape, and the lower housing 6 is arranged so that the inner peripheral surface of the cylindrical portion of the lower housing 6 is in pressure contact with the outer peripheral surface of the stator 41 of the motor 4. It is fixed to the stator 41 by press fitting, and a motor lower space 14 in the low pressure side chamber 12 is formed between the motor 4 and the lower housing 6,
The lower space 14 is defined by the lower housing 6 with respect to the bottom oil sump 13.

The lower housing 6 may be press-fitted into the stator 41 such that the entire inner surface of the cylindrical portion of the lower housing 6 is pressed against the outer peripheral surface of the stator 41, or only the opening side of the cylindrical portion. It may be press-fitted, or only the bottom of the tubular portion may be press-fitted.

A concave portion 62 whose upper end is opened is formed in a part of the inner peripheral side of the cylindrical portion of the lower housing 6 and is one of a plurality of core cut portions 43 formed in the stator 41. When the lower housing 6 is press-fitted and fixed to the stator 41 by facing one to the recess 62,
The recess 62 is formed to communicate with the motor lower space 14 through the core cut portion 43, and the suction pipe 8 penetrates the casing 1 to open in the recess 62 of the lower housing 6. The opening 81 of the suction pipe 8 is communicated with the space 14 and the low-pressure side chamber 12 above the motor 4, and the refrigerant sucked from the opening 81 is discharged from the recess 62 to the lower space 14 and the motor 4.
Is guided to the low-pressure side chamber 12 above, and the bottomed tubular lower housing 6 prevents the suction surface from disturbing the oil surface of the bottom oil reservoir 13.

Further, one of the core cut portions 43 formed on the stator 41 faces the concave portion 62 as described above, and the remaining three core cut portions 43 are formed on the stator 41 as shown in FIG. When the lower housing 6 is press-fitted and fixed, at each core cut portion 43, the stator 4
1 and the lower housing 6 to form a working fluid passage 44 that communicates the lower space 14 and the low-pressure side chamber 12 above the motor 4 with the refrigerant gas introduced into the lower space 14, The working fluid passage 44 and the air gap 4 formed between the stator 41 and the rotor 42.
5, the suction gas is guided to the upper side of the motor 4 while cooling the motor 4 with the suction gas.

As described above, in this embodiment, since the stator 41 and the lower housing 6 are integrated by press fitting without a gap, the shaft center of the stator 41 and the shaft of the lower bearing 61 of the lower housing 6 are integrated. Since the axes can be aligned with each other without any gap between the cores and the axial center between the axial center of the stator 41 and the axial center of the lower bearing 61 of the lower housing 6 can be eliminated, as a result, the upper portion of the upper housing 3 can be prevented. The coaxial accuracy of the shaft center of the bearing 31 and the shaft center of the lower bearing 61 of the lower housing 6 is improved, and reliability is improved.

Further, since the lower housing 6 is fixed to the stator 41 by press fitting, it is possible to form the lower housing 6 with a light metal plate, which facilitates the weight reduction design.

Further, since the axial center deviation is reduced, the variation in the air gap of the motor 4 is reduced, and the gap between the lower housing 6 and the stator 41 which causes the axial center deviation due to the press fit can be eliminated. Therefore, the passage design can be easily performed by controlling the suction flow rate.

Moreover, the stator 41 of the motor 4 is
Since the lower housing 6 is fixed to the upper housing 3 with the bolts 33, the stator 41, to which the lower housing 6 is fixed by press fitting, can be firmly fixed to the upper housing 3, while the axial center of the upper bearing 31 of the upper housing 3 and the lower part The coaxial accuracy between the housing 6 and the shaft center of the lower bearing 61 can be improved.

Further, since the working fluid passage 44 is formed between the core cut portion 43 of the stator 41 of the motor 4 and the lower housing 6, the working fluid passage 44 having a desired passage resistance is formed in the stator of the lower housing 6. Four
Since the working fluid passage 44 having a constant passage area can be formed easily by press-fitting into 1, the variation of the passage resistance due to the misalignment of the axis can be suppressed and the passage design by controlling the suction flow rate can be achieved. Can be done easily.

Although the scroll type electric fluid machine has been described in the above embodiments, the present invention is not limited to the scroll type compressor, but may be a rotary compressor or the like as long as the upper and lower bearing housings for supporting the motor are provided. The present invention can be applied to other electric fluid machines, and is not limited to the low-pressure dome type compressor as in the embodiment, and can be applied to a high-pressure dome type electric fluid machine or an expander. .

[0034]

According to the invention of claim 1, the upper housing 3 having the upper bearing 31 for supporting the upper portion of the drive shaft 5 of the motor 4 is fixed in the closed casing 1, and the upper housing 3 is provided with The stator 41 of the motor 4 is fixed via the spigot fitting portion 32, and the lower housing 6 having the lower bearing 61 for supporting the lower portion of the drive shaft 5 is press-fitted and fixed to the stator 41. 41 and the lower housing 6 can be integrated by press fitting without a gap, and the axial center of the stator 41 and the axial center of the lower bearing 61 of the lower housing 6 can be aligned without a gap. Since the axial misalignment between the lower housing 6 and the lower bearing 61 can be eliminated, as a result, the axial center of the upper bearing 31 of the upper housing 3 and the lower housing 6 can be reduced. It is improved axial alignment with the axis of the parts bearing 61 can improve the reliability.

Further, since the lower housing 6 is fixed to the stator 41 by press fitting, it is possible to form the lower housing 6 with a lightweight sheet metal, which facilitates a lightweight design.

Further, since the deviation of the shaft center is reduced, the variation of the clearance of the air gap of the motor 4 is reduced, and the clearance between the lower housing 6 and the stator 41 which causes the shaft center deviation due to the press fit can be eliminated. Therefore, the passage design can be easily performed by controlling the suction flow rate.

According to the second aspect of the present invention, since the stator 41 of the motor 4 is fixed to the upper housing 3 by the bolts 33, the lower housing 6 is fixed to the upper housing 3 by press fitting. It is possible to improve the coaxial accuracy between the axial center of the upper bearing 31 of the upper housing 3 and the axial center of the lower bearing 61 of the lower housing 6 while firmly fixing.

According to the third aspect of the invention, since the working fluid passage 44 is formed between the stator 41 of the motor 4 and the lower housing 6, the working fluid passage 44 having a desired passage resistance is formed in the lower housing. 6 can be easily formed by press-fitting it into the stator 41, and the working fluid passage 44 having a constant passage area can be formed at all times, so that the variation of the passage resistance due to the axial misalignment can be suppressed and the suction flow rate can be controlled. The passage can be easily designed by.

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional view (cross-sectional view taken along line BB in FIG. 2) showing an embodiment of an electric fluid machine of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1 in the embodiment.

FIG. 3 is a vertical sectional view of a conventional electric fluid machine.

[Explanation of symbols]

 1 ... Casing 5 ... Drive shaft 3 ... Upper housing 6 ... Lower housing 31 ... Upper bearing 61 ... Lower bearing 32 ... Inlay fitting 33 ... Bolt 4 ... Motor 41 ... Stator 44 ... ... Working fluid passage

Front page continued (72) Inventor Kazuhiko Matsukawa 3-12, Chikko Shinmachi, Sakai City, Osaka Prefecture Daikin Industrial Co., Ltd. Sakai Manufacturing Co., Ltd. Inside the seaside factory (72) Inventor Toshio Ikeda 1304, Kanaokacho, Sakai City, Osaka Daikin Industry Co., Ltd. Kanaoka Factory

Claims (3)

[Claims] 1. A motor (4) in a closed casing (1).
An upper housing (3) having an upper bearing (31) for supporting an upper part of a drive shaft (5) of the motor, and the stator (41) of the motor (4) is fixed to the upper housing (3) with a spigot fitting portion. A lower housing (6) having a lower bearing (61) for supporting the lower portion of the drive shaft (5) is press-fitted into the stator (41) to be fixed. An electric fluid machine. 2. The electric fluid machine according to claim 1, wherein the stator (41) of the motor (4) is fixed to the upper housing (3) by bolts (33). 3. The electric fluid machine according to claim 1, wherein a working fluid passage (44) is formed between the stator (41) of the motor (4) and the lower housing (6).