JP2013068187A - Electric compressor - Google Patents

Abstract

A compact, lightweight, and efficient electric compressor is provided that prevents generation of a gap between an electric motor and a main casing and expansion of tact for cooling during shrink fitting.
A compression section, an electric motor for driving the compression section, and a main body casing including the compression section and the electric motor, the compression section and the stator of the electric motor being the main body casing. It is fixed to two adjacent cross-sectional portions of one inner wall, and the fixed portion of the compression portion to the main body casing and the fixed portion of the stator of the electric compressor are substantially orthogonal to each other. As a result, the main body casing is elastically deformed three-dimensionally to obtain a strong fastening force, and the main body casing is deformed into a cross shape to absorb the stress, so that the internal stress generated in the main body casing, the stator and the compression portion is relieved. . As a result, the main body casing is small and thin, and the reliability of the motor and the compression unit is improved without deteriorating the efficiency.
[Selection] Figure 1

Description

  The present invention relates to an electric compressor mainly used for a refrigerant compressor such as a vehicle air conditioner.

Conventionally, this type of electric compressor has been proposed in which an iron motor stator is directly shrink-fitted on an aluminum shell (see, for example, Patent Document 1).
In addition, there has been proposed one that fixes a motor by elastically deforming a motor housing (for example, see Patent Document 2). FIG. 13 shows a fixing method of the stator core and the motor housing in the electric compressor described in Patent Document 2. In a non-circular motor housing (shell) 115 having three bulged portions 115b, 115c, and 115d on the wall, external force is applied to the bulged portions 115b, 115c, and 115d to form fastening margins 115e, 115f, and 115g. After deforming outward and inserting the stator core (cylindrical motor stator) 32, the external force is released and fixed by fastening margins 115e, 115f, and 115g.
Furthermore, a structure in which a fixing member made of a material having a larger thermal expansion coefficient than that of the stator and the shell is engaged with the end face of the stator in the radial direction and is fixed by bolts by being sandwiched by the shell in the axial direction. . (For example, see Patent Document 3)
FIG. 14 shows a conventional electric compressor described in Patent Document 3. As shown in FIG. As shown in FIG. 14, a compressor body (shell) 101 formed in a hollow shape, a compression unit (not shown) that compresses fluid sucked into the compressor body 101, and a motor 102 that drives the compression unit, Through a fixing member 103 made of a material having a higher thermal expansion coefficient than the compressor main body 101 and the motor 102, and provided with an engaging portion that engages at least one of the motor 102 and the compressor main body 101 at a predetermined position in the circumferential direction. The motor 102 is fixed to the compressor main body 101. Specifically, the compressor main body 101 is divided into 101 a and 102 b, the fixing member 103 is sandwiched from the axial direction, and fixed with bolts 104.

JP-A-9-287585 Japanese Patent No. 4269907 JP 2003-343438 A

  However, in the case of shrink fitting shown in Patent Document 1, it is necessary to cool the housing after the housing is heated and the stator is inserted and fixed. There was a problem that efficiency and capital investment increased.

  Also, in the example shown in Patent Document 2, the stator core laminate plate may be deformed by the force generated by the external force deformation, and the motor efficiency may deteriorate, or the motor housing (shell) may be damaged. The problem was difficult to make small.

  Furthermore, in the case of Patent Document 3, since the fixing member 103 needs to be divided into two parts by sandwiching the compressor main body 101 and fastened with bolts, the fastening portion protrudes, and a sealing material and a plurality of bolts are required. It had a problem of having a harmful effect such as becoming.

The present invention solves the above-mentioned conventional problems, eliminates the need for an expansion of the compressor body (shell) and the need for a sealing material, and prevents deterioration of motor efficiency and increase in the thickness of the shell. An object is to provide an inexpensive electric compressor.

  In order to solve the above-described conventional problems, an electric compressor of the present invention includes a compression unit that performs suction, compression, and discharge of fluid, an electric motor that drives the compression unit, and a main body that includes the compression unit and the electric motor. A compressor, and the compressor and the stator of the electric motor are fixed to two adjacent cross-sections of the inner wall of the main casing, and the fixed portion of the compressing section to the main casing and the electric compressor It is set as the structure which exists in the position substantially orthogonal to the fixed part of the stator.

  As a result, the main casing is elastically deformed three-dimensionally to obtain a strong fastening force, and the main casing is deformed into a cross shape to absorb the stress, so that the main casing is thickened or excessively large in the stator and the compression section. It is possible to prevent the external force from being applied and deforming.

  In the electric compressor of the present invention, since the electric motor and the compression portion are fixed to the main casing only by the elastic deformation force of the main casing, the reduction in production efficiency and the increase in capital investment due to the necessity of the cooling time at the time of shrink fitting are mitigated. I can do it. In addition, the stress of the casing can be kept low, and the wall thickness can be reduced by design, so that the size and weight can be reduced. Furthermore, it is possible to provide a low-cost electric compressor because the number of parts such as shells and bolts is not increased.

Sectional view in the axial direction of the electric compressor according to the first embodiment of the present invention. Deformation explanatory drawing of the main body casing which fixes the stator of an electric motor in Embodiment 1 of this invention Fig. 3 is a cross-sectional view showing a state in which the stator of the electric motor is fixed to the main body casing in the first embodiment of the present invention. The longitudinal cross-sectional view which shows the fixed state of the stator and main body casing of the electric motor in Embodiment 1 of this invention The deformation | transformation state explanatory drawing of the main body casing which fixes a compression part (bearing holder) in Embodiment 1 of this invention The top view of the compression part (bearing holder) in Embodiment 1 of this invention The cross-sectional view which shows the fixed state to the main body casing of the compression part (bearing holder) in Embodiment 1 of this invention. The longitudinal cross-sectional view which shows the fixed state to the main body casing of the electric motor and compression part (bearing holder) in Embodiment 1 of this invention. Sectional drawing which shows the fixed state of the stator and main body casing of the electric motor in Embodiment 2 of this invention Deformation explanatory drawing of the main body casing which fixes a compression part (bearing holder) in Embodiment 2 of this invention The top view of the compression part (bearing holder) in Embodiment 2 of this invention Sectional drawing of the main body casing which fixes the stator of an electric motor in Embodiment 3 of this invention Cross-sectional view of a motor housing (main body casing) for fixing a stator core (motor stator) of a conventional electric compressor Sectional drawing which shows the fixed state of the motor (electric motor stator) and the compressor main body (main body casing) of the conventional electric compressor

  1st invention is equipped with the compression part which carries out the suction | inhalation of the fluid, compression, and discharge, the electric motor which drives the said compression part, the main body casing which incorporated the said compression part and the said electric motor, The said compression part and the said motor The stator is fixed to two adjacent cross sections of the inner wall of the main body casing, and the fixed portion of the compression portion to the main body casing is substantially perpendicular to the fixed portion of the stator of the electric compressor. The configuration is as follows. As a result, the main body casing is elastically deformed three-dimensionally to obtain a strong fastening force, and the main body casing is deformed into a cross shape to absorb the stress, so that the internal stress generated in the main body casing, the stator and the compression portion is relieved. It is possible to prevent the main casing from being thickened or from being deformed due to an excessive external force applied to the stator and the compression portion.

  A second invention includes a compression unit that performs suction, compression, and discharge of fluid, an electric motor that drives the compression unit, a main body casing that includes the compression unit and the electric motor, and the compression unit and the electric motor An electric compressor in which a stator is fixed to two adjacent cross-section portions of an inner wall of the main body casing, and the main body casing is elliptically shaped by two external forces facing from the outer wall side in one fixed cross section of the main body casing And then inserting one of the compression part or the stator of the electric motor and positioning in the axial direction, then releasing the external force and fixing it with a squeeze part configured in the radial direction, and the compression part or the stator of the electric motor The other part is fixed to the other cross section of the main casing in the same manner as described above, and acts on the other cross section with respect to the direction of the external force acting on the one cross section. There a direction substantially perpendicular configuration of external force. Thereby, the same effect as that of the first invention can be obtained.

  According to a third aspect of the present invention, the inner wall of the main body casing corresponding to the outer periphery of the stator of the motor is formed with a recess at least in the direction in which the external force acts, and the inner wall of the main body casing has a cross section to which the stator is fastened. Is an electric compressor in which a recess is formed at a location different from the direction in which the external force acts.

  According to a fourth aspect of the present invention, arc portions and D-cut concave portions are alternately formed on the outer periphery of the stator of the electric motor so as to correspond to the arc portions in the range of at least ± 45 degrees with respect to the direction in which the external force acts. The electric compressor has a recess formed in the inner wall of the main body casing.

  According to a fifth aspect of the invention, at least two arc portions are left on the outer periphery of the stator of the electric motor to form a concave portion in a polygonal shape, and the concave portion is positioned within a range of at least ± 45 degrees with respect to the direction in which the external force acts. As a form to do.

  According to a sixth aspect of the present invention, there is provided an electric compressor in which a concave portion is formed in at least ± 45 degrees with respect to a direction in which an external force acts on at least one of an inner wall of a main body casing having a cross section to which the compression portion is fixed or an outer periphery of the compression portion. is there.

  In a seventh aspect of the invention, the main body casing is an electric compressor formed of a metal material having a larger thermal expansion coefficient than the stator of the electric motor.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a longitudinal sectional view of an electric compressor according to a first embodiment of the present invention. The electric compressor shown in FIG. 1 has a main body casing 1 and a casing cover 1a sandwiching and fixing a compression portion 2 in the axial direction. The compression unit 2 has a scroll structure, and the orbiting scroll 4 performs a orbiting motion with respect to the fixed scroll 3 to compress the refrigerant gas from the outer periphery toward the center. The orbiting scroll 4 is driven by a shaft 6 a press-fitted into the rotor 6 of the electric motor 5. Electric motor 5
The stator 5a and the bearing holder 2a of the compression portion 2 are positioned and fixed in the radial direction to the main casing 1 by the method described below.

  FIG. 2 shows a cross-sectional shape to which the stator 5a of the electric motor 5 of the main body casing 1 is fastened. The inner wall of the main casing 1 has a substantially circular shape 14, but relief recesses A7a, 7b, 7c and 7d are formed at four locations. As shown in FIG. 2, when an external force is applied to the outer wall of the main casing 1 from above and below via a jig, the inner circular shape of the inner wall shortens the distance between the upper and lower inner walls as shown by the alternate long and short dash line in the figure, and between the left and right inner walls. It is deformed into an elliptical shape 15 with an increased distance, and the distances in the 45 ° and 135 ° directions do not change.

  FIG. 3 shows a state in which the stator 5 a of the electric motor 5 is inserted into the main body casing 1. In this embodiment, the stator 5a has six arcuate portions 9a, 9b, 9c, 9d, 9e, 9f on the outer periphery, leaving six equiangular portions, and D-shaped stator recesses 8a, 8b, 8c, 8d, 8e. 8f are alternately formed, and the pair of stator recesses 8a and 8d are arranged so as to be in the direction of opposing external forces acting on the main body casing 1. The four relief recesses 7a, 7b, 7c and 7d formed in the main casing 1 are escapes when the stator 5a is inserted into the stator 5a with the inner wall of the main casing being deformed into an elliptical shape. It will be. That is, the stator arc portions 9a, 9b, 9d, and 9e at both ends of the pair of stator recesses 8a and 8d of the stator 5a are formed to escape portions that interfere with the inner wall of the main body casing 1.

  In the form as described above, when the external force acting from above and below is released, the inner wall of the main body housing 1 tries to return to a perfect circle shape due to elasticity, but it is fixed at the two right and left shimeshiro portions 10a and 10b in the figure. Since the outer diameter dimension of the stator arc portion of the child 5a is set to be about 0.3 to 0.5 mm larger than the inner diameter dimension of the main body housing 1, the shimillo portions 10a and 10b are formed and the stator 5a is positioned and fixed.

  In this configuration, the stator 5a is temporarily fixed to the main body housing 1. However, since the squeezing portions 10a and 10b of the main body casing 1 are two on the left and right, the stator 5a remains on the main body even though an elliptical shape having a long axis on the left and right remains. Positioned and fixed to the casing 1.

  However, in the cross section AA, there is no physical restriction in the vertical direction. When the main body housing is an aluminum alloy, the allowable tension in the wall is reduced from that of iron in terms of material strength, so that the fastening force between the main body housing and the stator 5a is reduced. Even if the pressure and temperature increase, it becomes difficult to design at a sufficient level.

  Therefore, in the present invention, as shown in FIG. 4, the bearing holder 2 a of the compression portion 2 is then attached to the main body casing 1 in a different cross section BB next to the cross section AA where the stator 5 a of the same main body casing 1 is fixed. It is positioned and fixed by the same method using elastic deformation force. Hereinafter, the configuration will be described.

  FIG. 5 shows that when the bearing holder 2a is positioned and fixed to the main body casing 1, an external force is applied from the left and right to the outer wall of the cross section BB for fixing the bearing holder 2a of the main body casing 1 to the inner wall of the perfect circle shape 14 of the main body casing 1. Is deformed into an elliptical shape 15 that shortens the distance between the left and right walls. In this case, relief recesses B11a and 11b are formed on the inner wall of the main body casing 1 on the left and right sides. As shown in FIG. 6, a bearing holder having a perfect circle shape and a diameter larger than the inner diameter of the true circle portion of the main body casing 1 2a has a shape that can be inserted into the body casing 1 that has been deformed into an elliptical shape by an external force.

FIG. 7 shows a state in which the bearing holder 2 a is positioned and fixed on the BB cross section of the main body casing 1. In this case, both ends 10a, 10b, 1 of the upper and lower inner wall circular arc portions 12a, 12b
At four points 0c and 10d, a squeezing portion is generated, and the main body casing 1 positions and fixes the bearing holder 2a to the main body casing 1 in a state in which the shape of the long-axis ellipse remains in the vertical direction.

  FIG. 8 is a longitudinal sectional view showing a state in which the bearing holder 2a of the compression unit 2 is positioned and fixed after the electric motor 5 is positioned and fixed to the main casing 1. Thus, by adopting a form in which the direction of the external force acting oppositely acts from a direction substantially perpendicular to the adjacent cross section, the adjacent main body casing 1 fixes the stator 5a to the adjacent cross section AA. Is also affected as an axial continuum, and the elliptical shape having a major axis in the left-right direction in the cross-section B-B, and the elliptical shape having a major axis in the vertical direction alone in the cross-section A-A is changed to a cross shape. Therefore, the fastening force of the stator 5a in the cross section AA is increased. Conversely, the deformed shape of the AA cross section similarly affects the BB cross section, and changes to a form in which a strong fastening force can be obtained by the interaction due to the difference in the deformation direction of the adjacent cross sections with respect to the tightening force of the single cross section. .

(Embodiment 2)
A second embodiment is shown in FIGS. In FIG. 9, among the six stator recesses 8a, 8b, 8c, 8d, 8e, and 8f provided on the outer periphery of the cylindrical stator 5a, there is an external force direction in the vertical direction that acts on the main body housing 1. The pair of recesses 8a and 8d is configured to be positioned and fixed at an inclination rather than orthogonal to the external force. Inner wall relief recesses B7a and 7c corresponding to the stator arc portions 9a and 9d in the stator 5a are formed in a cross section AA where the stator is positioned on the inner wall of the main body housing 1, and the outer wall of the main body housing 1 is vertically Therefore, even if the inner wall is deformed from a perfect circular shape 14 to an elliptical shape 15 having a long axis on the left and right, the stator 5a can be inserted without interference. In this embodiment, the shimoshiro portions are 10a, 10b, 10c, and 10d corresponding to the four arc portions 9b, 9c, 9d, and 9f.

  On the other hand, FIG. 10 shows a cross section BB of the main body casing 1 to which the bearing holder 2a of the compression section 2 is fixed, and FIG. 11 shows the shape of the bearing holder 2a. In FIG. 10, the inner wall of the main casing 1 has a perfect circle shape, and bearing holder recesses 13a and 13b are formed on the left and right sides of the outer periphery of the bearing holder 2a shown in FIG. That is, an external force that is opposed to the left and right direction acts on the BB cross section of the main body casing 1, and the BB cross section of the main body housing 1 has an elliptical shape 15 having a major axis in the vertical direction indicated by a one-dot chain line from the perfect circle shape 14. After the bearing holder 2a is inserted in a state of being elastically deformed, when the external force acting on the main body casing 1 is released from the left and right, the shimoshiro portions 10a, 10b, 10c, and 10d are formed and positioned and fixed.

  As in the first embodiment, the directions of the external forces in the cross-sections AA and BB are almost orthogonal to each other, and each other acts in the axial direction as in the first embodiment. It is done.

(Embodiment 3)
FIG. 12 shows the third embodiment. In this embodiment, in addition to the six stator recesses 9a, 9b, 9c, 9d, 9e, 9f provided on the outer periphery of the cylindrical stator 5a, the external force acting in the vertical direction acting on the main body housing 1 is used. A pair of stator second recesses 16a and 16b is newly formed at a place where the existing arc portion exists, and has a polygonal shape. In this case, the inner wall of the cross section AA of the main body housing 1 is elastically deformed from a perfect circle shape 14 to an elliptical shape 15 having a long axis in the left-right direction by an external force in the vertical direction, and the stator 5a described above is inserted, and the external force The state where the position is fixed by releasing is shown. In this embodiment, the scissors are formed at 10a, 10b, 10c, and 10d.

  Also in this case, the same effect can be obtained by positioning and fixing the bearing holder by applying an external force from a direction substantially perpendicular to the cross section AA in the adjacent cross section BB as in the first and second embodiments. Is obtained.

  Each embodiment has been described above, but it goes without saying that the effect is the same if the opposing external forces acting on the cross section are substantially orthogonal to the direction of the external forces acting on different neighboring cross sections.

  Further, the outer diameter shape of the stator has been described in the case of a shape close to a regular hexagon of equiangular distribution with an arc portion remaining, but the pseudo-equal angle distribution shape with at least two arc portions left as shimeshiro portions. It may be a polygonal shape.

  As described above, the electric compressor according to the present invention is small, lightweight, efficient, reliable, and can be fixed to the main casing of the compressor and the compressor unit. It can be applied not only to compressors, but also to applications in the field of home appliances such as room air conditioners and water heaters that require small size and light weight.

1 Body casing 2 Compression part 2a Bearing holder (compression part)
5 Electric motor 5a Stator 6 Rotor 6a Shaft 7a, 7b, 7c, 7d Inner wall relief recess A (recess)
8a, 8b, 8c, 8d, 8e, 8f Stator arc part (arc part)
9a, 9b, 9c, 9d, 9e, 9f Stator recess (recess)
10a, 10b, 10c, 10d Shimeshiro portion 11a, 11b Inner wall relief recess B (recess)
12a, 12b Bearing holder arc part (arc part)
13a, 13b Bearing holder recess (recess)
14 Perfect circle shape 15 Ellipse shape 16a, 16b Stator second recess (recess)

Claims (7)

A compression section that sucks, compresses and discharges fluid; an electric motor that drives the compression section; and a main body casing that houses the compression section and the electric motor. The compression section and the stator of the electric motor are the main body. An electric motor that is fixed to two adjacent cross-sections of the inner wall of the casing, and that the compression portion of the compression portion to the main body casing is substantially perpendicular to the fixed portion of the stator of the electric compressor. Compressor. A compressor that performs suction, compression, and discharge of fluid; an electric motor that drives the compressor; and a main body casing that incorporates the compressor and the electric motor; and the main body includes the compressor and the stator of the motor. An electric compressor fixed to two adjacent cross sections of the inner wall of the casing, wherein the main casing is elastically deformed into an elliptical shape by two external forces facing from the outer wall side in one fixed cross section of the main casing. After inserting one of the compression part or the stator of the electric motor and positioning in the axial direction, the external force is released and fixed in the radial part constructed in the radial direction, and the other part of the compression part or the stator of the electric motor is Fixing to the other cross section of the main casing in the same way, and the direction of the external force acting on the other cross section with respect to the direction of the external force acting on the one cross section Configuration and the electric compressor but generally perpendicular. A recess is formed in the inner wall of the main body casing corresponding to the outer periphery of the stator of the electric motor at least in a direction in which the external force acts, and a direction in which the external force acts on the inner wall of the main body casing in a cross section to which the stator is fastened. The electric compressor according to claim 1 or 2, wherein recesses are formed at different locations. Arc portions and D-cut concave portions are alternately formed on the outer periphery of the stator of the electric motor, and concave portions are formed on the inner wall of the main body casing so as to correspond to the arc portions in a range of at least ± 45 degrees with respect to the direction in which the external force acts. The electric compressor according to claim 1 or 2. 4. A configuration in which at least two arc portions are left on the outer periphery of the stator of the electric motor to form a concave portion in a polygonal shape, and the concave portion is positioned in a range of at least ± 45 degrees with respect to a direction in which an external force acts. Or the electric compressor of 4. 5. The structure according to claim 3 or 4, wherein a recess is formed in at least one of an inner wall of the main body casing having a cross section to which the compression portion is fixed or an outer periphery of the compression portion in a range of at least ± 45 degrees with respect to a direction in which an external force acts. Electric compressor. 7. The electric compressor according to any one of claims 1 to 6, wherein the main body casing is made of a metal material having a larger coefficient of thermal expansion than the stator of the electric motor.