JP2025086366A - Electric Compressor - Google Patents

Abstract

To suppress transmission of vibration generated in a stator to an inner circumferential surface of a housing, and ensure a sufficient area of a refrigerant flow path.SOLUTION: Provided is a scroll compressor in which a motor 50 for driving a scroll compression mechanism includes a stator 51 and a rotor 52, the stator 51 has an outer circumference portion 51b and a plurality of tooth portions 51a, the outer circumference portion 51b has a first cut portion 51c1 formed in a first position and a second cut portion 51c2 formed in a second position and having a longer length in a circumferential direction CD than the first cut portion 51c1, the first position where the first cut portion 51c1 is formed is surrounded by a region where the outer circumference portion 51b is in contact with an inner circumferential surface 30a of a front housing 30, and the second position where the second cut portion 51c2 is formed is surrounded by a region where the outer circumference portion 51b is not contact with the inner circumferential surface 30a of the front housing 30 and a refrigerant flow path 10b for allowing a refrigerant to flow through the inner circumferential surface 30a is formed.SELECTED DRAWING: Figure 2

Description

This disclosure relates to an electric compressor.

Conventionally, there is known an electric compressor that compresses a refrigerant by driving the compressor with a motor (see, for example, Patent Document 1). In Patent Document 1, positioning portions are provided at multiple positions in the circumferential direction of the outer circumferential surface of the stator, and fastening bolts inserted into the positioning portions are fastened to the housing to fix the stator to the housing.

JP 2022-60787 A

One method known for fixing a stator to a housing that houses a motor without using fastening bolts is to heat the housing to expand it, insert the stator in that state, and perform shrink fitting so that the outer periphery of the stator comes into contact with the inner periphery of the housing.

However, if the outer periphery of the stator is brought into contact with the inner periphery of the housing by shrink fitting, the vibrations generated in the stator when the motor is driven are transmitted to the inner periphery of the housing via the outer periphery of the stator, causing large vibrations on the surface of the housing. Furthermore, if the area where the outer periphery of the stator and the inner periphery of the housing come into contact is large, it is not possible to ensure a sufficient area for the refrigerant flow path to circulate the refrigerant that has flowed into the housing to the compressor.

This disclosure has been made in consideration of these circumstances, and aims to provide an electric compressor that reduces the transmission of vibrations generated in the stator when the motor is driven to the inner surface of the housing via the outer periphery of the stator, and that can ensure a sufficient area for the refrigerant flow path.

A scroll compressor according to one aspect of the present disclosure includes a housing formed in a cylindrical shape extending along an axis, a compression section disposed inside the housing and rotating about the axis to compress a refrigerant, and a motor that drives the compression section to rotate about the axis. The motor includes a stator disposed inside the housing so as to extend along the axis, and a rotor disposed on the inner periphery of the stator. The stator has an outer periphery and a plurality of teeth disposed at a plurality of positions in the circumferential direction around the axis so as to protrude from the outer periphery toward the axis, and around which a coil winding is wound. The outer periphery has a first notch formed at a first position included in the multiple circumferential positions where the teeth are arranged, and a second notch formed at a second position included in the multiple circumferential positions where the teeth are arranged and has a longer circumferential length than the first notch, the first position where the first notch is formed is a position sandwiched between areas where the outer periphery is in contact with the inner periphery of the housing, and the second position where the second notch is formed is a position sandwiched between areas where the outer periphery is not in contact with the inner periphery of the housing, and a refrigerant flow path through which the refrigerant flows is formed on the inner periphery.

This disclosure makes it possible to provide an electric compressor that reduces the transmission of vibrations generated in the stator when the motor is driven to the inner surface of the housing via the outer periphery of the stator, and that can ensure a sufficient area for the refrigerant flow path.

1 is a vertical cross-sectional view showing a schematic configuration of a scroll compressor according to an embodiment of the present disclosure. 2 is a cross-sectional view of the scroll compressor shown in FIG. 1 taken along the line AA. FIG. 3 is a cross-sectional view of the stator shown in FIG. 2 .

A scroll compressor (electric compressor) 100 according to one embodiment of the present disclosure will be described with reference to the drawings. The scroll compressor 100 of this embodiment is used, for example, in a vehicle air conditioner.

Figure 1 is a vertical cross-sectional view showing the schematic configuration of a scroll compressor 100 according to this embodiment. As shown in Figure 1, the scroll compressor 100 includes a bearing housing (first housing) 10, a rear housing (second housing) 20, a front housing (third housing) 30, a scroll compression mechanism (compression section) 40, a motor 50, a bearing section 60, an inverter 70, and a gasket 80.

The bearing housing 10, rear housing 20, and front housing 30 form the outer shell of the scroll compressor 100 and are made of an aluminum alloy. The bearing housing 10 is formed in a cylindrical shape along the axis X1, which is the center around which the orbiting scroll 42 orbits. The bearing housing 10 has an internal space that houses the bearing portion 60 and the scroll compression mechanism 40.

The rear housing 20 seals one end of the bearing housing 10 along the axis X1, and is provided with a discharge port (not shown) for the refrigerant gas compressed by the scroll compression mechanism 40. The front housing 30 seals the other end of the bearing housing 10 along the axis X1, and is provided with an internal space that houses the motor 50 and the inverter 70. The internal space of the front housing 30 that houses the motor 50 is connected to the internal space of the bearing housing 10 that houses the bearing portion 60. The internal space that houses the motor 50 and the internal space that houses the inverter 70 are independent spaces that do not communicate with each other.

The front housing 30 is provided with an intake port 31 for drawing in the refrigerant. The refrigerant supplied from the outside is introduced into the internal space of the front housing 30 from the intake port 31. The refrigerant introduced into the front housing 30 passes through the motor 50 along the axis X1 and is guided toward the scroll compression mechanism 40. The refrigerant drawn in from the intake port 31 is a mixed refrigerant (fluid) containing lubricating oil and refrigerant gas.

The bearing housing 10 and the rear housing 20 have insertion holes into which the fastening bolts 90 are inserted. The end of the front housing 30 on the bearing housing 10 side has fastening holes (not shown) into which the male threads formed at the tip of the fastening bolts 90 are fastened. The bearing housing 10 is fixed in a state where it is sandwiched between the rear housing 20 and the front housing 30 along the axis X1 by fastening the fastening bolts 90 into the fastening holes formed in the front housing 30.

The scroll compression mechanism 40 is a device that is disposed inside the bearing housing 10 and rotates around the axis X1 to compress the refrigerant gas. The scroll compression mechanism 40 has a fixed scroll 41 that is sandwiched and fixed between the bearing housing 10 and the rear housing 20, and an orbiting scroll 42 that meshes with the fixed scroll 41. The scroll compression mechanism 40 compresses the refrigerant gas by revolving the orbiting scroll 42 relative to the fixed scroll 41 using the driving force of the motor 50.

The fixed scroll 41 has a spiral wrap (first wall) 41B, which is a wall erected on one side of the end plate (first end plate) 41A. The end plate 41A has a discharge port 41C formed therein through which the refrigerant gas compressed by the fixed scroll 41 and the orbiting scroll 42 is discharged.

The orbiting scroll 42 has a spiral wrap (second wall) 42B, which is a wall erected on one side of the end plate (second end plate) 42A. The orbiting scroll 42 is connected to an eccentric shaft (not shown) that is connected to the motor 50, and is supported so that it can freely rotate orbitally via a rotation prevention mechanism (not shown). The orbiting scroll 42 is supported so that it can rotate orbitally while being prevented from rotating by engaging with the spiral wrap 41B of the fixed scroll 41.

As shown in FIG. 1, the scroll compression mechanism 40 has a reed valve 43 attached to the fixed scroll 41 so as to close the discharge port 41C. The reed valve 43 opens when the pressure of the refrigerant gas in the compression chamber 40A is equal to or higher than a predetermined pressure, and guides the refrigerant gas discharged from the discharge port 41C to the discharge space 41D. The refrigerant gas guided to the discharge space 41D is guided to the outside from a discharge port (not shown).

The motor 50 is a device that drives the orbiting scroll 42 of the scroll compression mechanism 40 to rotate around the axis X1 relative to the fixed scroll 41. The motor 50 is connected to the orbiting scroll 42 via an eccentric shaft (not shown). Here, the details of the motor 50 will be described with reference to Figures 2 and 3. Figure 2 is a cross-sectional view of the scroll compressor 100 shown in Figure 1 taken along the line A-A. Figure 3 is a cross-sectional view of the stator shown in Figure 2. As shown in Figures 2 and 3, the motor 50 has a stator 51, a rotor 52 arranged on the inner periphery of the stator 51, and a drive shaft 53 connected to the rotor 52.

The stator 51 is formed by stacking a predetermined number of electromagnetic steel sheets that have been punched into an annular shape. The stator 51 is disposed inside the front housing 30 so as to extend along the axis X1. As shown in Figures 2 and 3, a plurality of teeth 51a are provided on the inner periphery of the stator 51. A coil winding (not shown) is wound around each of the plurality of teeth 51a of the stator 51 via a bobbin (not shown).

As shown in FIG. 3, the stator 51 has a plurality of teeth 51a and an outer periphery 51b to which the teeth 51a are connected. The outer periphery 51b is formed in an annular shape around the axis X1 and has a first outer diameter D1 centered on the axis X1. The teeth 51a are arranged at a plurality of positions (nine positions P1, P2, P3, P4, P5, P6, P7, and P8 shown in FIG. 2) in the circumferential direction CD around the axis X1 so as to protrude from the outer periphery 51b toward the axis X1.

2 and 3, the outer peripheral portion 51b has a first notch 51c1 formed at positions P1, P2, P4, P5, P7, and P8 (first positions) included in the multiple positions P1 to P9 in the circumferential direction CD where the multiple teeth portions 51a are arranged, and a second notch 51c2 formed at positions P3, P6, and P9 (second positions) included in the multiple positions P1 to P9 in the circumferential direction CD where the multiple teeth portions 51a are arranged. The length (second length) L2 of the second notch 51c2 in the circumferential direction CD is longer than the length (first length) L1 of the first notch 51c1 in the circumferential direction CD.

The first notch 51c1 and the second notch 51c2 are arranged at equal intervals along the circumferential direction CD at multiple positions where the teeth 51a are arranged (9 positions P1, P2, P3, P4, P5, P6, P7, and P8 shown in FIG. 2). The second notch 51c2 are arranged at three positions, positions P3, P6, and P9, at intervals of 120 degrees.

As shown in FIG. 2, in the circumferential direction CD, the regions between positions C1 and C2, between positions C3 and C4, and between positions C5 and C6 are regions where the outer circumferential portion 51b of the stator 51 contacts the inner circumferential surface 30a of the front housing 30. Positions P1, P2, P4, P5, P7, and P8 where the first cutout portion 51c1 is formed are positions sandwiched between the regions where the outer circumferential portion 51b contacts the inner circumferential surface 30a of the front housing 30.

Positions P1 and P2 are located between the contact area between position C1 and position C2 of the outer periphery 51b of the stator 51 and the inner periphery 30a of the front housing 30. Positions P4 and P5 are located between the contact area between position C3 and position C4 of the outer periphery 51b of the stator 51 and the inner periphery 30a of the front housing 30. Positions P7 and P8 are located between the contact area between position C5 and position C6 of the outer periphery 51b of the stator 51 and the inner periphery 30a of the front housing 30.

Position P3 is a position sandwiched between the area where the outer peripheral portion 51b and the inner peripheral surface 30a of the front housing 30 do not contact each other (area from position C2 to position C3), and a refrigerant flow path 10b through which refrigerant gas flows is formed on the inner peripheral surface 30a. Position P6 is a position sandwiched between the area where the outer peripheral portion 51b and the inner peripheral surface 30a of the front housing 30 do not contact each other (area from position C4 to position C5), and a refrigerant flow path 30b through which refrigerant gas flows is formed on the inner peripheral surface 30a. Position P9 is a position sandwiched between the area where the outer peripheral portion 51b and the inner peripheral surface 30a of the front housing 30 do not contact each other (area from position C6 to position C1), and a refrigerant flow path 10b through which refrigerant gas flows is formed on the inner peripheral surface 30a.

As shown in FIG. 3, the length L1 of the first cutout 51c1 in the circumferential direction CD is shorter than the length L3 (third length) of the inner end of the tooth 51a in the circumferential direction CD. The second length L2 of the second cutout 51c2 in the circumferential direction CD is longer than the length L3 of the inner end of the tooth 51a in the circumferential direction CD.

The bearing unit 60 is a member that supports a rotating shaft (not shown) that rotates around the axis X1 by the motor 50. An eccentric shaft that is eccentrically disposed with respect to the axis X1 is provided at the end of the rotating shaft on the scroll compression mechanism 40 side.

The inverter 70 is a device that generates a drive voltage to drive the motor 50 and controls the rotation speed of the motor 50.

The gasket 80 is a member that is disposed between the end face 20a of the bearing housing 10 on the rear housing 20 side and the end face of the rear housing 20 on the bearing housing 10 side, and forms a seal area to prevent refrigerant from leaking out from between the end face 10a and the end face 20a.

The operation and effects of the scroll compressor 100 of the present embodiment described above will be described.
According to the scroll compressor 100 of this embodiment, the positions P1, P2, P4, P5, P7, and P8 of the first notch 51c1 formed in the outer circumferential portion 51b of the stator 51 are positions sandwiched between the regions where the outer circumferential portion 51b of the stator 51 contacts the inner circumferential surface 30a of the front housing 30. Therefore, the vibration of the teeth portion 51a arranged at the positions P1, P2, P4, P5, P7, and P8 is transmitted to the inner circumferential surface 30a of the front housing 30 via the outer circumferential portion 51b. On the other hand, since the first notch 51c1 is arranged at the positions P1, P2, P4, P5, P7, and P8 in the circumferential direction CD where the teeth portion 51a is arranged, the vibration directly transmitted from the teeth portion 51a to the inner circumferential surface 30a of the front housing 30 can be reduced compared to the case where the first notch 51c1 is not arranged.

In addition, according to the scroll compressor 100 of this embodiment, the positions P3, P6, and P9 of the second cutout portion 51c2 formed in the outer circumferential portion 51b of the stator 51 are sandwiched between the regions where the outer circumferential portion 51b of the stator 51 and the inner circumferential surface 30a of the front housing 30 do not contact each other, and are positions where the refrigerant flow passage 30b through which the refrigerant flows is formed on the inner circumferential surface 30a. Since the second cutout portion 51c2 is positioned at the positions P3, P6, and P9 in the circumferential direction CD where the teeth portion 51a is positioned, the area of the refrigerant flow passage can be sufficiently secured compared to the case where the second cutout portion 51c2 is not positioned.

According to the scroll compressor 100 of this embodiment, the length L1 in the circumferential direction CD of the first cutout portion 51c1 is shorter than the length L3 in the circumferential direction CD of the inner peripheral end portion of the teeth portion 51a. Therefore, the contact area between the outer peripheral portion 51b of the stator 51 and the inner peripheral surface 30a of the front housing 30 can be sufficiently secured, and the holding force with which the inner peripheral surface 30a of the front housing 30 holds the stator 51 can be sufficiently secured.

In addition, according to the scroll compressor 100 of this embodiment, the length L2 in the circumferential direction CD of the second cutout portion 51c2 is longer than the length L3 in the circumferential direction CD of the inner end portion of the teeth portion 51a. Therefore, in the region where the outer circumferential portion 51b of the stator 51 and the inner circumferential surface 30a of the front housing 30 do not contact each other, the area of the refrigerant flow path 30b can be sufficiently secured.

In addition, according to the scroll compressor 100 of this embodiment, the first notch 51c1 and the second notch 51c2 formed on the outer periphery 51b of the stator 51 are arranged in a balanced manner with equal pitch on the radial outside of the teeth 51a, so that the vibration of the teeth 51a can be averaged and reduced compared to when they are arranged in an unbalanced manner.

The electric compressor according to the present embodiment described above can be understood, for example, as follows.
An electric compressor (100) according to a first aspect of the present disclosure includes a housing (10, 20, 30) formed in a cylindrical shape extending along an axis (X1), a compression section (40) disposed inside the housing and rotating about the axis to compress a refrigerant, and a motor (50) that rotationally drives the compression section about the axis, the motor including a stator (51) disposed inside the housing so as to extend along the axis, and a rotor (52) disposed on an inner peripheral side of the stator, the stator having an outer circumferential portion (51b) and a plurality of teeth portions (51a) disposed at a plurality of positions in a circumferential direction (CD) around the axis so as to protrude from the outer circumferential portion toward the axis, and around which a coil winding is wound, The portion has a first notch (51c1) formed at a first position (P1, P2, P4, P5, P7, P8) included in the multiple circumferential positions where the multiple teeth portions are arranged, and a second notch (51c2) formed at a second position (P3, P6, P9) included in the multiple circumferential positions where the multiple teeth portions are arranged and has a longer circumferential length than the first notch, the first position where the first notch is formed is a position sandwiched between an area where the outer circumferential portion contacts an inner circumferential surface of the housing, and the second position where the second notch is formed is a position sandwiched between an area where the outer circumferential portion and the inner circumferential surface of the housing do not contact, and a refrigerant flow path (10b) through which the refrigerant flows is formed on the inner circumferential surface.

According to the electric compressor according to the first aspect of the present disclosure, the first position of the first notch formed on the outer periphery of the stator is a position sandwiched between the areas where the outer periphery of the stator contacts the inner periphery of the housing. Therefore, vibrations of the teeth located at the first position are transmitted to the inner periphery of the housing via the outer periphery. Meanwhile, because the first notch is located at the first circumferential position where the teeth are located, it is possible to reduce vibrations transmitted directly from the teeth to the inner periphery of the housing compared to a case where the first notch is not located.

In addition, according to the electric compressor according to the first aspect of the present disclosure, the second position of the second notch formed in the outer periphery of the stator is a position that is sandwiched between an area where the outer periphery of the stator and the inner periphery of the housing do not contact, and where a refrigerant flow path is formed on the inner periphery. Since the second notch is positioned at the second circumferential position where the teeth are positioned, the area of the refrigerant flow path can be sufficiently secured compared to the case where the second notch is not positioned.

The electric compressor according to the second aspect of the present disclosure is the first aspect, and further includes the following configuration. That is, the first circumferential length (L1) of the first notch is shorter than the circumferential length (L3) of the inner circumferential end of the teeth, and the second circumferential length (L2) of the second notch is longer than the circumferential length of the inner circumferential end of the teeth.

According to the electric compressor according to the second aspect of the present disclosure, the first circumferential length of the first notch is shorter than the circumferential length of the inner circumferential end of the teeth. This ensures a sufficient area of contact between the outer circumferential portion of the stator and the inner circumferential surface of the housing, thereby ensuring sufficient holding force of the inner circumferential surface of the housing to hold the stator.

In addition, in the electric compressor according to the second aspect of the present disclosure, the second circumferential length of the second notch is longer than the circumferential length of the inner end of the teeth. Therefore, a sufficient area of the refrigerant flow path can be secured in the region where the outer periphery of the stator does not contact the inner periphery of the housing.

The electric compressor according to the third aspect of the present disclosure is the first or second aspect, and further includes the following configuration. That is, the multiple first notches and the multiple second notches are arranged at equal intervals along the circumferential direction.

In the electric compressor according to the third aspect of the present disclosure, the multiple first notches and second notches are arranged in a balanced manner at equal intervals along the circumferential direction on the radial outside of the teeth, so that the vibration of the teeth can be averaged and reduced compared to when they are arranged in an unbalanced manner.

10 Bearing housing 10a End surface 10b Refrigerant flow path 20 Rear housing 20a End surface 30 Front housing 30a Inner peripheral surface 30b Refrigerant flow path 31 Suction port 40 Scroll compression mechanism (compression section)
Reference Signs List 40A Compression chamber 41 Fixed scroll 41A End plate 41B Spiral wrap 41C Discharge port 41D Discharge space 42 Orbiting scroll 43 Reed valve 50 Motor 51 Stator 51a Teeth portion 51b Outer periphery 51c1 First notch portion 51c2 Second notch portion 52 Rotor 53 Drive shaft 60 Bearing portion 70 Inverter 80 Gasket 90 Fastening bolt 100 Scroll compressor (electric compressor)
CD Circumferential direction D1 First outer diameter X1 Axis

Claims (3)

A housing formed in a cylindrical shape extending along an axis;
a compression section disposed inside the housing and rotating about the axis to compress a refrigerant;
a motor that rotates the compression unit about the axis;
The motor is
a stator disposed inside the housing and extending along the axis;
a rotor disposed on an inner circumferential side of the stator,
The stator has an outer periphery and
a plurality of teeth portions arranged at a plurality of positions in a circumferential direction around the axis line so as to protrude from the outer circumferential portion toward the axis line, and around which a coil winding is wound,
the outer circumferential portion has a first notch portion formed at a first position included in the plurality of positions in the circumferential direction where the plurality of teeth portions are arranged, and a second notch portion formed at a second position included in the plurality of positions in the circumferential direction where the plurality of teeth portions are arranged and has a length in the circumferential direction longer than that of the first notch portion,
the first position where the first notch is formed is a position between an area where the outer circumferential portion is in contact with an inner circumferential surface of the housing,
The second position where the second notch is formed is a position that is sandwiched between an area where the outer circumferential portion and the inner circumferential surface of the housing do not contact each other, and where a refrigerant flow path through which the refrigerant flows is formed on the inner circumferential surface. a first length of the first cutout portion in the circumferential direction is shorter than a length of an inner peripheral side end of the tooth portion in the circumferential direction;
The electric compressor according to claim 1 , wherein a second circumferential length of the second cutout portion is longer than a circumferential length of an inner peripheral side end of the tooth portion. The electric compressor according to claim 1 , wherein the first cutouts and the second cutouts are disposed at equal intervals along the circumferential direction.