JP2012110174A - Stator housing structure of electromotor and electrically-driven type compressor using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stator housing structure of an electromotor, capable of assembling a ridge formed on the periphery of a laminate core so as not to interfere the housing without reducing the performance of the electromotor and increasing the size of the sheet steel plate.SOLUTION: The stator housing structure of an electromotor is configured to house a stator 31 formed by winding a coil around a laminate core 34 formed by laminating a plurality of sheet steel plates in a housing 2. A ridge 61 formed on the periphery of the laminate core is provided to a recess 62 formed on the inner peripheral surface of the housing 2 to house the stator 31 in the housing 2.

Description

  The present invention relates to a stator housing structure for housing a stator in a housing of an electric motor and an electric compressor using the same.

A stator used for an electric motor is formed by laminating a plurality of thin steel plates punched by pressing to form a laminated core, and winding a coil around the laminated core. It is formed by welding and fixing the side surfaces of the thin steel plates by spot irradiation with a laser beam along the laminating direction (axial direction of the electric motor). It is preferable that welding of such a laminated core is performed at a part where magnetic property change due to material change due to welding heat hardly occurs, for example, the outer peripheral part of a thin steel plate, but the welded part swells outward, In the spot irradiation as described above, a convex portion extending in the stacking direction is generated on the outer peripheral portion of the stacked core. Moreover, in order to weld, the convex part extended in the lamination direction of a thin steel plate may be previously formed in the outer peripheral part of a lamination | stacking core, and this convex part may be welded.
For this reason, if a raised portion is formed on the outer peripheral portion of the stator by the convex portion generated by welding or the welded convex portion, the raised portion interferes with the inner peripheral surface of the housing that houses the stator, and the stator Inconveniences such as being unable to be accommodated in a predetermined position of the housing.

  Therefore, conventionally, as shown in Patent Document 1 described below, in order to prevent interference between a convex portion (projection) generated by welding and a housing that houses the stator, welding is performed on a welded portion of a thin steel plate. It is proposed that a concave portion deeper than the convex portion (projection) generated by the above is formed in advance, and the convex portion does not protrude from the side surface of the thin steel plate by welding at the concave portion. .

JP 2000-209792 A

However, when a concave portion deeper than the convex portion (projection) generated by welding is formed in advance on the thin steel plate as described above, the area of the steel plate for forming the effective magnetic path is reduced. This makes it difficult to obtain the performance of the electric motor originally desired. For this reason, in order to ensure the performance of the electric motor, it is necessary to increase the area of the thin steel plate. However, if the area of the thin steel plate is increased, it is against the request for miniaturization of the electric motor.
In addition, when forming a recess in a thin steel plate, it is a normal design to provide a recess on the opposite side of the tooth that has little influence on the magnetic path, but depending on the specifications of the motor, a recess is provided at such a location. Sometimes you can't.

  The present invention has been made in view of such circumstances, and does not impair the performance of the electric motor, does not increase the thickness of the thin steel plate, and is formed on the outer peripheral portion of the laminated core (generated by welding). And a stator housing structure of an electric motor that can be assembled without interfering with the housing of the convex portion or the convex portion formed in advance for welding, and an electric compressor using this structure The main challenge is to provide

In order to achieve the above object, a stator housing structure according to the present invention houses a stator formed by winding a coil on a laminated core formed by laminating a plurality of thin steel plates and fixing them by welding. A stator housing structure for an electric motor configured as described above, wherein a raised portion formed on an outer peripheral portion of the laminated core is disposed in a recess formed on an inner peripheral surface of the housing, and the stator is accommodated in the housing. It is characterized by.
Here, as the raised portion formed on the outer peripheral portion of the laminated core, a portion obtained by welding convex portions formed in advance in the stacking direction in order to weld the outer peripheral portions of the plurality of thin steel plates, or a plurality of thin steel plates The convex part etc. which are produced | generated by the lamination direction by welding the outer peripheral part of this are assumed.

  Accordingly, the raised portion formed on the outer peripheral portion of the laminated core is disposed and accommodated in the concave portion formed on the inner peripheral surface of the housing. Therefore, when the stator is accommodated in the housing, the raised portion becomes the inner circumference of the housing. There is no interference with the surface, and there is no need to form a recess for forming the raised portion in the thin steel plate, so there is no inconvenience affecting the performance of the motor.

  Here, in consideration of the ease of assembly of the stator to the housing, when a plurality of the raised portions are formed at intervals on the outer peripheral portion of the stator, they are axisymmetric with respect to the central axis of the stator. You may make it form in a position.

  In addition, as an electric compressor using such a stator housing structure of an electric motor, the housing is further provided with a compression mechanism, and the compression mechanism is driven by the electric motor, and is formed on the inner peripheral surface of the housing. The recessed portion formed may be constituted by a working fluid circulation recess formed on the inner peripheral surface of the housing in order to guide the working fluid introduced into the housing to the compression mechanism.

According to such a configuration, since the working fluid circulation recess for guiding the working fluid introduced into the housing to the compression mechanism is also used as the recess in which the raised portion is disposed, each recess is provided independently. This eliminates the necessity (no need to newly form a concave portion for disposing the raised portion on the inner peripheral surface of the housing separately from the concave portion for circulating the working fluid), and makes it possible to avoid an increase in the size of the compressor, and the raised portion. This eliminates the need to newly process and form a recess for placing the.
Further, since the raised portion is disposed in the recess, heat exchange with the working fluid (intake refrigerant gas) is relatively increased, and cooling of the stator of the electric motor can be promoted.

  As described above, according to the present invention, the raised portion formed on the outer peripheral portion of the laminated core of the stator (the convex portion generated by welding or the convex portion previously formed for welding is welded. In this case, it is not necessary to provide a recess in the stator in order to avoid interference with the housing. For this reason, it becomes possible to provide a raised portion at an arbitrary position on the outer periphery of the laminated core without affecting the effective magnetic path of the laminated core, and avoiding an increase in size of the electric motor while maintaining the performance of the electric motor. It becomes possible.

  In addition, since the raised portion generated on the outer peripheral portion of the laminated core is disposed in the concave portion formed on the inner peripheral surface of the housing, it is not necessary to cut the raised portion in order to avoid interference with the housing. Thus, it is possible to reduce the manufacturing process. Moreover, since the raised portion is disposed in the concave portion of the housing and functions as a stopper that restricts movement of the stator in the circumferential direction, rotation of the stator can be prevented.

  In addition, if the plurality of raised portions generated at intervals on the outer peripheral portion of the stator are generated at positions that are line-symmetric with respect to the central axis of the stator, the stator can be assembled to the housing in the operation of assembling the stator. It is possible to increase the degree of freedom of assembly.

  If the concave portion formed in the inner peripheral surface of the housing is constituted by the concave portion for circulating the working fluid formed in the inner peripheral surface of the housing in order to guide the working fluid introduced into the housing to the compression mechanism, It is no longer necessary to newly form a recess for arranging the portion on the inner peripheral surface of the housing separately from the recess for circulating the working fluid, and it is possible to avoid an increase in the size of the compressor, and a new recess for arranging the raised portion is provided. Therefore, the work of forming and forming is unnecessary. Further, since the raised portion (convex portion) is arranged in the concave portion for circulating the working fluid, the contact area between the surface of the stator and the working fluid (suction refrigerant gas) increases, and the stator and the working fluid (suction refrigerant) It is possible to relatively increase the heat exchange with the gas), so that it is possible to promote the cooling of the stator of the electric motor.

FIG. 1 is a cross-sectional view illustrating a configuration example of an electric compressor. FIG. 2 is a view showing a laminated core formed by laminating a plurality of thin steel plates and welding an outer peripheral portion, (a) is a view of the laminated core as viewed from the axial direction, and (b) is It is a perspective view of a lamination core. FIG. 3 is a perspective view showing a housing (motor housing member) that houses the stator. FIG. 4A is a diagram (a diagram viewed from line AA in FIG. 1) of a housing (motor housing housing member) that houses the stator as seen from the inverter housing member, and FIG. It is a figure which shows the state which accommodated the stator in this housing (electric motor accommodation housing member). FIG. 5 is a perspective view showing another configuration example of the laminated core.

  Hereinafter, an example in which the stator housing structure of the present invention is employed in an electric compressor will be described with reference to the drawings.

  FIG. 1 shows an electric compressor 1 suitable for a refrigeration cycle using a refrigerant as a working fluid. This electric compressor 1 is provided with a compression mechanism 3 on the left side in the figure in a housing 2 made of an aluminum alloy, and an electric motor 4 for driving the compression mechanism on the right side in the figure. Yes. In FIG. 1, the right side in the figure is the front of the compressor, and the left side in the figure is the rear of the compressor.

  The housing 2 includes an inverter circuit including a compression mechanism housing member 2 a that houses the compression mechanism 3, an electric motor housing member 2 b that houses the electric motor 4 that drives the compression mechanism 3, and an inverter circuit 5 that drives and controls the electric motor 4. The inverter housing member 2c that houses the substrate 6 is positioned by the positioning pin 38 in the axial direction and fastened by the fastening bolt 39 in the axial direction.

A partition wall 49 formed integrally with a shaft support portion 8a is provided on the side of the motor housing housing member 2b that faces the compression mechanism housing housing member 2a, and is opposed to the motor housing housing member 2b of the inverter housing housing member 2c. A partition wall 50 in which the shaft support portion 8b is integrally formed is provided on the side to be driven, and the drive shaft 10 is rotatably supported by the shaft support portions 8a and 8b of the partition walls 49 and 50 via bearings 11 and 12, respectively. Yes. Due to the partition walls 49 and 50 formed in the motor housing housing member 2b and the inverter housing housing member 2c, the inside of the housing 2 houses the compression mechanism housing portion 9a for housing the compression mechanism 3 from the rear, and the motor housing portion for housing the motor 4. 9b and an inverter accommodating portion 9c that accommodates the inverter circuit board 6.
In this example, the inverter accommodating portion 9c that accommodates the inverter circuit board 6 is closed by attaching the lid 7 to the inverter accommodating housing member 2c.

  The compression mechanism 3 is of a scroll type having a fixed scroll member 13 and an orbiting scroll member 14 disposed opposite thereto, and the fixed scroll member 13 is a disc-shaped end plate fixed inside the rear portion of the housing 2. 13a, a cylindrical outer peripheral wall 13b that is provided over the entire periphery along the outer edge of the end plate 13a and is erected forward, and forward from the end plate 13a inside the outer peripheral wall 13b. It is comprised from the spiral-shaped spiral wall 13c extended toward the direction.

  The orbiting scroll member 14 is composed of a disk-shaped end plate 14a and a spiral spiral wall 14c erected rearward from the end plate 14a, and is formed on the back surface of the end plate 14a. An eccentric shaft 10a that is provided at the rear end portion of the drive shaft 10 and is eccentric with respect to the shaft center of the drive shaft 10 is connected to the boss portion 14b via a bush 15 and a bearing 16, and the shaft center of the drive shaft 10 is centered. As supported by revolving motion.

  The fixed scroll member 13 and the orbiting scroll member 14 are meshed with each other with their respective spiral walls 13c and 14c, and the ends of the spiral walls 13c and 14c of the respective scroll members 13 and 14 are end plates 14a of the mating scroll member. Therefore, a compression chamber 17 is defined in a space surrounded by the end plate 13a and the spiral wall 13c of the fixed scroll member 13 and the end plate 14a and the spiral wall 14c of the orbiting scroll member 14. Has been.

  Further, a thin plate-shaped annular thrust trace 18 is sandwiched between the outer peripheral wall 13b of the fixed scroll member 13 and the end face of the partition wall 49, and the fixed scroll member 13 and the partition wall 49 connect the thrust trace 18 to each other. It is faced through.

  The thrust trace 18 is formed of a material having excellent wear resistance, and a central hole is formed in the center through which a boss portion 14b of the orbiting scroll member 14 and an Oldham ring 24 described later are inserted. The fixed scroll member 13, the thrust trace 18, and the motor housing housing member 2 b are positioned and fixed by positioning pins 19 that are inserted into pin insertion holes formed in the thrust trace 18.

  The shaft support portion 8a formed integrally with the partition wall 49 of the electric motor housing member 2b has a through hole in the center, and its inner surface is formed in a stepwise manner in diameter toward the thrust trace 18, From the front side farthest from the thrust trace 18, a bearing portion accommodating portion 21 that accommodates the bearing 11, and a weight accommodating portion that accommodates the balance weight 22 that is integrated with the bush 15 and rotates as the drive shaft 10 rotates. 23, an Oldham housing portion 25 for housing an Oldham ring 24 formed from an end surface of the partition wall 49 and preventing the orbiting scroll member 14 from rotating with the orbiting scroll member 14 is formed.

  Therefore, the orbiting scroll member 14 is rotated by the rotation of the drive shaft 10, but revolves around the axis of the drive shaft 10 while the rotation is restricted by the Oldham ring 24.

  Between the outer peripheral wall 13b of the fixed scroll member 13 and the outermost peripheral portion of the spiral wall 14c of the orbiting scroll member 14, the suction chamber for sucking the refrigerant introduced from the suction port 40 described later through the suction passage 41. 26, and the refrigerant gas compressed in the compression chamber 17 is discharged behind a fixed scroll member 13 in the housing through a discharge hole 27 formed substantially at the center of the fixed scroll member 13. A chamber 28 is defined between the rear end wall of the compression mechanism housing member 2a. The refrigerant gas discharged into the discharge chamber 28 is pumped to the external refrigerant circuit through the discharge port 29.

  On the other hand, the stator 31 and the rotor 32 which comprise the electric motor 4 are provided in the electric motor accommodating part 9b formed in the part ahead of the axial support part 8a in the housing 2. As shown in FIG. The stator 31 includes a cylindrical laminated core 34 and a coil 35 wound around the cylindrical core 34, and is fixed to the inner surface of the housing 2 (electric motor housing member 2b). The drive shaft 10 is fixed with a rotor 32 made of a magnet rotatably accommodated inside the stator 31, and the rotor 32 is rotated by a rotating magnetic force formed by the stator 31. Is designed to rotate. The stator 31 and the rotor 32 constitute an electric motor 4 composed of a brushless DC motor.

  A suction port 40 for sucking refrigerant gas is formed on the side surface of the housing 2 (motor housing member 2b) facing the motor housing portion 9b, and between the stator 31 and the housing 2 (motor housing housing member 2b). The electric motor from the suction port 40 is formed through a gap formed later, a hole formed in the partition wall 49, and a gap formed between the fixed scroll member 13 and the housing 2 (compression mechanism housing member 2a). A suction path 41 that guides the refrigerant flowing into the storage portion 9b to the suction chamber 26 is configured.

  In addition, 51 is an inverter side cluster connected to the inverter circuit 5 mounted on the inverter circuit board 6 via the cable 53, and 52 is connected to the coil 35 of the stator 31 via the cable 54. It is a motor side cluster, and the inverter side cluster 51 is attached from the side (right side in the figure) to a portion protruding from the inverter accommodating portion 9c of the relay terminal (airtight terminal) 55 attached to the inverter accommodating housing member 2c. In addition, by attaching the motor-side cluster 52 to the portion of the relay terminal (airtight terminal) 55 protruding from the motor housing portion 9b from the side surface (left side in the figure), the inverter circuit 5 and the stator 31 are connected to the relay terminal 55. The inverter circuit 5 supplies power to the motor 4 through electrical connection.

  Accordingly, when the rotor 32 rotates and the drive shaft 10 rotates, the orbiting scroll member 14 is rotated about the eccentric shaft 10 a in the compression mechanism 3, so that the orbiting scroll member 14 has the axis of the fixed scroll member 13. Revolve around. At this time, since the orbiting scroll member 14 is prevented from rotating by the rotation preventing mechanism including the Oldham ring 24, only the revolving motion is allowed.

  By the revolving motion of the orbiting scroll member 14, the compression chamber 17 moves from the outer peripheral side of the scroll walls 13c, 14c of both scroll members to the center side while gradually reducing the volume, so that the suction chamber 26 sucks into the compression chamber 17. The compressed refrigerant gas is compressed, and the compressed refrigerant gas is discharged into the discharge chamber 28 through the discharge hole 27 formed in the end plate 13 a of the fixed scroll member 13. Then, it is sent to the external refrigerant circuit via the discharge port 29.

In FIG. 2, details of the laminated core 34 of the stator 31 are shown. The laminated core 34 of the stator 31 is formed by laminating and laminating a plurality of thin steel plates 60 punched by a press punching die, and irradiating the outer peripheral portion with a laser beam, so that the outer peripheral portion of the laminated thin steel plates 60 is formed. It is melted and joined.
In this example, when the projection 61a for welding is formed in the outer periphery of each thin steel plate, and the laminated core 34 is formed by laminating a plurality of thin steel plates 60, it is shown in FIG. Thus, a projection 61a for welding extending along the lamination direction of the thin steel plate 60 is formed on the outer peripheral portion of the laminated core 34 by the projection 61a of each thin steel plate 34. Welding is performed by irradiating light rays. The welded convex portion 61 constitutes a raised portion extending in the stacking direction on the outer peripheral portion of the stacked core 34.

As shown in FIGS. 3 and 4, the gap between the stator 31 and the housing 2 (the motor housing housing member 2 b) constituting a part of the suction path 41 is formed in the housing 2 (the motor housing housing member 2 b). The concave portions 62 and the convex portions 63 extending in the axial direction are alternately formed on the inner peripheral surface in the circumferential direction, and the outer peripheral portion of the laminated core 34 is brought into contact with the convex portion 63, thereby forming the concave portion 62. It is formed by a gap between the outer peripheral portion of the laminated core 34 and the inner wall of the electric motor housing member 2b.
In this example, the recesses 62 are formed with a width of about 50 degrees as the central angle, and are formed at four locations in the circumferential direction with a phase difference of 90 degrees. A portion where 62 is not formed is a convex portion 63 having a width of about 40 degrees with a phase difference of 90 degrees.

  The convex portion 61 is formed on the outer peripheral portion of the laminated core 34 in accordance with the formation position of the concave portion 62 of the housing 2 (electric motor housing member 2b). The convex portions are formed at eight locations on the outer peripheral portion of the laminated core 34 so that two pairs of convex portions 61 are accommodated in the circumferential direction (the two convex portions 61 that form a pair are approximately It is formed in four places with a phase difference of 90 degrees).

  Here, the convex portion 61 does not need to be formed on the opposite side of the tooth 60a, and is in an appropriate position according to the position of the concave portion 62 formed on the inner peripheral surface of the housing 2 (the motor housing member 2b). In the above-described example, the recess 62 is formed in a position that is line-symmetric with respect to the central axis of the housing 2 (the motor housing member 2b) (with a 90 ° phase shift). Accordingly, the convex portion 61 is also formed at a position that is line-symmetric with respect to the central axis of the stator 31.

  The outer diameter of the portion of the laminated core 34 ((thin steel plate 60) where the convex portion 61 is not formed is substantially equal to the inner diameter of the convex portion 63 of the motor housing housing member 2b, and the convex portion 61 of the laminated core 34 is formed. The stator 31 is fixed to the inner surface of the convex portion 63 of the housing 2 (electric motor housing member 2b) by means such as press-fitting a laminated core.

  Therefore, according to the above configuration, the convex portion 61 of the laminated core 34 is disposed in the concave portion 62 that constitutes a part of the suction path 41 formed on the inner peripheral surface of the housing 2 (the motor housing member 2b). If the stator 31 is accommodated in the housing 2 (the motor accommodating housing member 2b), the convex portion 61 does not interfere with the housing 2 (the electric motor accommodating housing member 2b), and the convex portion is formed on the thin steel plate as in the prior art. There is no need to form a recess for forming. For this reason, there is no inconvenience affecting the performance of the electric motor 4, and it is possible to avoid an increase in the size of the electric motor 4.

Further, in the above-described configuration, the concave portion 62 on the inner peripheral surface of the housing used as the refrigerant passage is used as a concave portion in which the convex portion 61 formed on the outer peripheral portion of the laminated core 34 of the stator 31 is disposed (stored). Therefore, it is not necessary to newly process a concave portion for accommodating the convex portion 61 without changing the shape of the housing 2 (electric motor housing member 2b).
And since it is not necessary to form a recessed part in the thin steel plate 60, since the performance of the electric motor 4 does not depend on the production | generation position of the convex part 61, the convex part 61 is made arbitrary in the outer peripheral part of the thin steel plate 60. It can be generated at the position, and can be appropriately changed according to the position of the recess 62 formed on the inner peripheral surface of the housing.

Furthermore, since the convex portion 61 is accommodated in the concave portion 62 of the housing, the convex portion 61 can function as a stopper that restricts the rotation of the laminated core 34 in the circumferential direction. It becomes possible to prevent. In addition, since the convex portion 61 is disposed in the concave portion 62 (suction passage 41) of the housing, the contact area between the surface of the laminated core 34 of the stator 31 and the suction refrigerant gas increases, and the stator 31 and the suction refrigerant. Heat exchange with gas can be relatively increased, and cooling of the stator 31 of the electric motor 4 can be promoted.
Further, in the above-described configuration, the convex portion 61 is formed at a position that is point-symmetric with respect to the center of the stator 31, so that the circumferential direction between the stator 31 and the housing 2 (the motor housing member 2b) is increased. The fixing position can be adjusted, and the degree of freedom in assembling the stator 31 can be increased.

  In the above configuration, the protruding portion 61 extending in the stacking direction formed in advance on the outer peripheral portion of the laminated core 34 in order to weld a plurality of thin steel plates is used as the raised portion formed on the outer peripheral portion of the laminated core. Although comprised by the welded part, as FIG. 5 shows, the convex part 65 produced | generated by welding to the outer peripheral part of a laminated core may be sufficient as the protruding part formed in the outer peripheral part of a laminated core. Even in the case where such a convex portion 65 is formed, it is possible to obtain the same function and effect as in the above configuration example by accommodating in the concave portion 62 formed in the housing.

DESCRIPTION OF SYMBOLS 1 Electric type compressor 2 Housing 2b Motor accommodation housing member 3 Compression mechanism 4 Electric motor 31 Stator 34 Laminated core 35 Coil 60 Sheet steel plate 61 Convex part 62 Concave part 63 Convex part 65 Convex part

Claims (4)

A stator housing structure for an electric motor configured by housing a stator formed by winding a coil on a laminated core formed by laminating a plurality of thin steel plates and welding and fixing,
A stator housing structure for an electric motor, wherein the stator is housed in the housing by disposing a raised portion formed on an outer circumferential portion of the laminated core in a recess formed on an inner circumferential surface of the housing.   The raised portion is formed by welding a convex portion formed in advance in the laminating direction in order to weld the outer peripheral portions of the plurality of thin steel plates, or by laminating the outer peripheral portions of the plurality of thin steel plates. The stator accommodating structure for an electric motor according to claim 1, wherein the stator accommodating structure is a convex portion generated in a step.   3. The plurality of raised portions are formed on the outer peripheral portion of the stator with a space therebetween, and are formed at positions that are line symmetric with respect to the central axis of the stator. Motor stator housing structure. An electric compressor using the stator housing structure for an electric motor according to claim 1,
The housing is further provided with a compression mechanism, and the compression mechanism is driven by the electric motor. The recess formed in the inner peripheral surface of the housing is used as the working fluid introduced into the housing. An electric compressor characterized by comprising a working fluid circulation recess formed in the inner peripheral surface of the housing for guiding.

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