JP2008274966A - Motor driven compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor driven compressor integral with a driving circuit part such as an inverter, wherein a motor driving circuit is sufficiently cooled and is reduced in size. <P>SOLUTION: The motor driven compressor comprises a housing in which a compression part, a motor part 5, and an electric circuit part are arrayed in the longitudinal direction. A suction fluid passage through which fluid to be compressed by a compression mechanism passes is provided passing through a part where the electric circuit part exists, in the axial direction while deviating from the axis of the housing. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electric compressor, and more particularly to an electric compressor in which an electric circuit such as a compressor and a drive electric circuit unit is integrally formed.

  Some electric compressors used in air conditioners and the like have a motor and a compressor that are integrally housed in a housing to achieve compactness. In this type of electric compressor, it is necessary to cool both the compressor and the motor, but there are some which cool the motor with a refrigerant for compression. In addition, in a type in which a motor is driven by an inverter, there is an electric compressor that is further downsized by housing a motor drive circuit such as an inverter together in a housing of the compressor.

  As a conventional example of such an electric compressor, there is one in which a motor drive circuit unit such as an inverter is integrally formed on an axial side surface of a suction cooling motor housing of an electric compressor and a suction pipe is installed on the side surface of the motor housing. (For example, refer to Patent Document 1).

However, in the above configuration, the motor drive circuit section is cooled only on the side surface in the axial direction of the housing of the suction cooling type motor, so that the motor drive circuit is not sufficiently cooled, and the motor drive circuit cannot be sufficiently downsized. There is a problem.
JP 2002-70743 A

  The present invention has been made in view of the above-described circumstances, and in the case where a drive circuit unit such as an electric compressor and an inverter is integrally formed, the motor drive circuit is sufficiently cooled, and the motor drive circuit can be reduced in size. Accordingly, an object of the present invention is to provide an electric compressor in which the overall size of the inverter-integrated electric compressor is reduced, the mounting property is improved, and the weight is reduced.

  According to the first aspect of the present invention, a compression unit that sucks and compresses fluid from the suction port and discharges fluid from the discharge port, and a motor unit including a motor that is connected to the compression unit and drives the compression unit, A substantially cylindrical housing that houses at least the compression section and the motor, an electric circuit section related to the motor, and an intake fluid passage through which the fluid to be compressed is guided from the outside, and the electric circuit section; The motor part is partitioned by a partition, and the compression part, the motor part, and the electric circuit part are aligned in the longitudinal direction, and the electric circuit part is disposed at the most upstream end on the suction side in the longitudinal direction of the housing. The suction fluid passage is shifted from the axial center of the housing in the axial direction through the electrical circuit portion, and the fluid flows through the fluid passage into the motor portion and then reaches the suction port. To do.

  By configuring in this way, since the intake refrigerant passage passes through the electric circuit portion, the cooling performance of the electric circuit portion is improved, and the reliability of the electric circuit elements and the like included in the electric circuit portion is improved, The electric circuit part can be downsized.

  According to a second aspect of the present invention, in the electric compressor according to the first aspect, the partition walls are airtight.

  As a result, the electric circuit portion is partitioned from the other compartments in the housing in an airtight state by the partition wall, so that it is not affected by moisture or the like from the other compartments.

  According to a third aspect of the present invention, in the first or second aspect, a cooling wall that is thermally connected to at least one of a wall and a partition wall surrounding the suction fluid passage is further provided in the electric circuit portion. It is characterized by.

  According to the present embodiment, the cooling area is increased by providing the cooling wall in the electric circuit portion, and the cooling efficiency is improved by intensively cooling these components by installing the components requiring cooling on the cooling wall. And further miniaturization can be achieved.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the housing and the suction fluid passage are integrally formed.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, at least two of the housing, the partition wall, and the suction fluid passage are integrally formed. Features.

  According to a sixth aspect of the present invention, in the third aspect, at least two of the housing, the partition, the suction fluid passage, and the cooling wall are integrally formed.

  In the above-described aspects of the fourth to sixth aspects, since two or more components of the compressor are integrally formed, manufacturing and assembly can be simplified and cost reduction can be achieved.

  According to a seventh aspect of the present invention, in any one of the first to sixth aspects, the electric compressor is for an air conditioner, and the fluid is a refrigerant. . According to this form, the form which actualizes the use etc. of this invention more is disclosed.

  An electric compressor according to an embodiment of the present invention described below includes a compression unit that sucks and compresses fluid from a suction port and discharges the fluid from a discharge port, and is connected to the compression unit to drive the compression unit. A motor portion including a motor to perform, a substantially cylindrical housing that accommodates at least the compression portion and the motor, an electric circuit portion related to the motor, and an intake through which the fluid to be compressed is guided and passed from the outside And a suction fluid passage through which the fluid reaches the suction port of the compression unit. The electric circuit portion is accommodated in the housing on the upstream side of the suction port of the compression portion, and the suction fluid passage passes through a portion where the electric circuit portion exists in the housing.

  By adopting this configuration, the electric circuit portion does not protrude in the circumferential direction from the housing of the electric compressor, and particularly in the case where the electric compressor is mounted horizontally, the center of gravity and the balance in the direction of gravity are better. Therefore, vibration and noise associated with high center of gravity and unbalance can be suppressed.

  In addition, since the sucked fluid flows smoothly and simply in the order of the electric circuit portion, the motor portion, and the compression portion, and the electric circuit portion is cooled by a lower temperature fluid, the cooling efficiency can be improved.

  In addition, the electric circuit part can be separated from other sections such as a motor part in the housing by the partition wall, and an electric circuit component can be mounted on the partition wall for cooling.

  Hereinafter, embodiments of an electric compressor according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic partial sectional side view of an electric compressor 1 (hereinafter referred to as a compressor 1) according to a first embodiment of the present invention. The compressor 1 of this Embodiment is a compressor of air conditioning apparatuses, for example for vehicles. The compressor 1 includes a cylindrical housing 11 that surrounds the entire compressor, and a front housing 12 (left side in FIG. 1) that is a lid at the front end, and the front housing 12 is sealed with bolts. Thus, the pressure vessel is formed. However, it may be fastened so as to be sealed by another method. In the housing 11, the motor unit 3 that is a driving unit is provided at the approximate center in the longitudinal direction, the compression unit 2 that compresses the refrigerant gas at the front (left side in FIG. 1), and the rear (right side in FIG. 1). The motor drive circuit unit 6 is provided.

  The motor unit 3 includes a motor 5 configured by a stator fixed to the housing 11 and a rotor configured by a plurality of permanent magnets therein. The rotor is fixedly supported on a rotating shaft 4 passing through the center on the inner side, and the rotating shaft 4 is rotatably supported by a housing 11 via a bearing. The end of the rotating shaft 4 is connected to the compression unit 2 and transmits the driving force of the motor unit 3 to the compression unit 2. In the present invention, the details of the compression unit 2 do not affect the present invention, and thus detailed description of the structure and the like is omitted.

  As shown in FIG. 1, an intake refrigerant passage 22 is provided at the rear portion of the housing 11, and the intake refrigerant passage 22 communicates with an external refrigerant circuit (not shown) via the intake port 16. The refrigerant gas compressed by the refrigerant flows through the external refrigerant circuit to the compressor 1 through the suction port 16 and the suction refrigerant passage 22. The flow of the refrigerant gas flows from the intake port 16 through the intake refrigerant passage 22 into the housing 11, and cools the motor unit 3 with the low-temperature intake refrigerant gas. Thereafter, the refrigerant flows through the refrigerant passage (not shown) of the motor unit 3 to the compression unit 2. The refrigerant is compressed in the compression unit 2 and discharged to the external refrigerant circuit through the discharge port 17 provided in the front housing 12. The flow of the refrigerant is as described above, and the motor portion in the housing 11 that is the pressure vessel of the compressor 1 is filled with the low-pressure refrigerant gas.

  In the present embodiment, as described above, the motor drive circuit unit 6 is provided at the rear portion (right side in FIG. 1) of the housing 11. A partition wall 21 is provided between the motor unit 3 and the motor drive circuit unit 6 to maintain airtightness between the motor unit 3 and the motor drive circuit unit 6. In the present embodiment, the motor drive circuit unit 6 includes an electric circuit component 33 such as an electric component related to driving of a motor such as an inverter. Electricity supplied to the motor unit 3 is supplied from the outside to the motor 5 through the motor drive circuit via the power supply terminal 31 installed in the housing 11 and through the hermetic terminal 32 having an airtight structure.

  In the present embodiment, the housing 11 is formed of an aluminum alloy having good thermal conductivity, but other materials may be used. As described above, the electric compressor 1 includes the housing 11 made of aluminum alloy or the like, and the compression portion 3, the motor 5, and the motor drive circuit portion 6 are built and fixed. In the motor drive circuit portion 6, an intake refrigerant passage 22 connected to the intake port 16 is formed integrally with the housing 11 in the axial direction, and the intake refrigerant passage 22 is connected to the motor portion 3. In the motor drive circuit unit 6, a cooling wall 23 that connects the partition wall 21 to the motor unit, the suction refrigerant passage 22, and the housing 11 is integrally formed.

  In the present embodiment, a flat plate-like cooling wall 23 is provided so as to connect the wall forming the suction refrigerant passage 22 and the housing 11 and to cross the substantially center of the housing 11. Further, various electric circuit components 33, hermetic terminals 32, and the like are appropriately arranged in the motor drive circuit unit 6. The cooling wall 23 formed integrally with the partition wall 21 and the suction refrigerant passage 22 between the motor unit 3 and the motor drive circuit unit 6 is provided with an electric circuit component 33 that particularly requires cooling in the motor drive circuit unit 6. An electric circuit component 33 (such as a power element or a capacitor) that can be miniaturized by cooling is fixed with a screw or the like. Further, the motor drive circuit unit 6 is isolated from the outside by a cover 24 as shown in FIG. 1, and has a waterproof function. As described above, confidentiality is maintained in the motor unit 3, and the motor unit 3 is cooled by the suction refrigerant.

  The cooling of the motor drive circuit by the low-pressure and low-temperature suction refrigerant will be described.

  As described above, the low-pressure and low-temperature intake refrigerant introduced from the intake port 16 passes through the intake refrigerant passage 22 and enters the motor unit 3, cools the motor 5, and is then compressed by the compression unit 2. It is discharged from. With this configuration, the motor drive circuit is cooled by heat conduction by the suction refrigerant. The cooling heat by the refrigerant is transmitted to the electric circuit component 33 provided in the motor drive circuit unit 6 through the wall of the suction refrigerant passage 22, the partition wall 21, and the cooling wall 23, and cools these electric circuit components 33. In particular, as described above, the electric circuit component 33 installed on the partition wall 21 or the cooling wall 23 can be effectively cooled.

  Next, a reference example of the present invention will be described with reference to FIG. FIG. 2 is a schematic partial cross-sectional side view similar to FIG. 1 of the electric compressor 50 of the present reference example. Referring now to FIG. 2, the element parts of FIG. 2 that are the same as or similar to the element parts of the first embodiment disclosed in FIG. 1 described above are designated by the same reference numerals.

  In the present reference example, an intake refrigerant passage 22 connected to the intake port 16 is formed substantially at the center of the shaft of the motor drive circuit unit 6 with the housing 11, and the intake refrigerant passage 22 is formed at the end of the rotating shaft 4. The refrigerant passage 51 communicates with the motor unit 3. The refrigerant flows into the motor unit 3 from the suction refrigerant passage 22 through the refrigerant passage 51.

  FIG. 3 is a cross-sectional view taken along the line AA when the compressor 50 according to the second embodiment in FIG. 2 is viewed from the rear. According to FIG. 3, the suction refrigerant passage 22 passes through substantially the center of the cylindrical housing 11, and a flat cooling wall 23 is provided so as to connect the wall forming the suction refrigerant passage 22 and the housing 11. Yes. Further, various electric circuit components 33, hermetic terminals 32, and the like are appropriately arranged in the motor drive circuit unit 6. According to the present reference example, the suction refrigerant passage 22 is substantially at the center of the axis of the housing 11, so that the cooling efficiency and the overall balance of the motor drive circuit unit 6 are better than those of the first embodiment. May be better.

  Next, effects and operations of the above embodiment will be described.

The following effects can be expected from the compressor 1 according to the first embodiment of the present invention.
-Since the intake refrigerant passage 22 passes through the motor drive circuit unit 6 and the cooling performance inside the motor drive circuit unit 6 is improved, only the electric circuit component 33 installed on the surface of the partition wall 21 with the motor unit 3 Instead, the reliability of the electric circuit elements inside the motor drive circuit unit 6 is improved, and the motor drive circuit unit 6 can be reduced in size.
・ Furthermore, by configuring the drive circuit unit integrally on the outer surface in the axial direction of the electric compressor, it is possible to make the outer shape of the electric compressor while maintaining the substantially cylindrical shape. When mounted on the, there are no problems such as no overhang in the circumferential direction, high center of gravity, or poor balance in the direction of gravity, and suppression of vibration and noise associated with high center of gravity and unbalance. it can.

In addition to the effects of the first embodiment, the following effects can be expected from the compressor 50 of the reference example of the present invention.
・ Because there is a cooling part almost at the center of the motor drive circuit part, the inside of the motor drive circuit part can be cooled more uniformly and efficiently than in the first embodiment, improving the reliability of the entire motor drive circuit part and further downsizing. Can be planned.

  Although the embodiments and reference examples described above show the electric compressor driven only by the electric motor, the invention can also be applied to a hybrid compressor driven by either the electric motor or the belt.

  Moreover, although the above-mentioned Example and reference example showed the vehicle electric compressor for engine mounting, it is not limited to engine mounting or vehicle use.

  The above-described embodiment is an example of the present invention, and the present invention is not limited by the embodiment, but is defined only by matters described in the claims, and other embodiments than the above are also possible. It can be implemented.

FIG. 1 shows a schematic partial sectional side view of an electric compressor 1 according to a first embodiment of the present invention. FIG. 2 is a schematic partial cross-sectional side view similar to FIG. 1 of an electric compressor 50 according to a reference example of the present invention. FIG. 3 shows an AA cross-sectional view of the compressor 50 according to the second embodiment of FIG. 2 as viewed from the rear.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,50 ... Electric compressor, 2 ... Compression part, 3 ... Motor part, 4 ... Rotary shaft, 5 ... Motor, 6 ... Motor drive circuit part, 11 ... Housing 12: Front housing 16 ... Suction port 21 ... Partition wall 22 ... Suction refrigerant passage 23 ... Cooling wall 24 ... Cover 31 ... Power supply terminal 32 ... Hermetic terminals, 33 ... Electrical circuit components.

Claims (7)

A compression unit that sucks and compresses fluid from the suction port and discharges the fluid from the discharge port;
A motor unit including a motor coupled to the compression unit and driving the compression unit;
A substantially cylindrical housing that houses at least the compression section and the motor;
An electrical circuit section associated with the motor;
A suction fluid passage through which the fluid to be compressed is guided and passed from outside,
The electric circuit portion and the motor portion are partitioned by a partition wall,
The compression section, the motor section, and the electric circuit section are aligned in the longitudinal direction, and the electric circuit section is disposed at the most upstream end on the suction side in the longitudinal direction of the housing,
The suction fluid passage is axially displaced from the axial center of the housing through the electric circuit portion,
The electric compressor according to claim 1, wherein the fluid passes through the fluid passage and flows into the motor unit, and then reaches the suction port.   The electric compressor according to claim 1, wherein the partition wall is airtight.   3. The electric motor according to claim 1, further comprising a cooling wall in the electric circuit portion, which is thermally connected to at least one of a wall surrounding the suction fluid passage and the partition wall. Compressor.   The electric compressor according to any one of claims 1 to 3, wherein the housing and the suction fluid passage are integrally formed.   5. The electric compressor according to claim 1, wherein at least two of the housing, the partition wall, and the suction fluid passage are integrally formed. 6.   The electric compressor according to claim 3, wherein at least two of the housing, the partition, the suction fluid passage, and the cooling wall are integrally formed.   The electric compressor according to any one of claims 1 to 6, wherein the electric compressor is for an air conditioner, and the fluid is a refrigerant.

Images