Electric compressor

Abstract

Provided is a scroll compressor. A motor (50) for driving a scroll compression mechanism comprises a stator (51) and a rotor (52). The stator (51) has an outer peripheral portion (51b) and a plurality of teeth portions (51a). The outer peripheral portion (51b) has: a first cutout portion (51c1) formed at a first position; and a second cutout portion (51c2) formed at a second position and having a longer length in the circumferential direction (CD) than the first cutout portion (51c1). The first position where the first cutout portion (51c1) is formed is a position sandwiched between regions where the outer peripheral portion (51b) contacts an inner peripheral surface (30a) of a front housing (30). The second position where the second cutout portion (51c2) is formed is a position sandwiched between regions where the outer peripheral portion (51b) and the inner peripheral surface (30a) of the front housing (30) do not contact one other, and a position where a refrigerant flow path (10b) through which a refrigerant flows is formed on the inner peripheral surface (30a).

Description

Electric compressor

[0001] The present disclosure relates to an electric compressor.

[0002] Conventionally, there has been known an electric compressor in which a motor drives the compressor to compress a refrigerant (see, for example, Patent Document 1). In Patent Document 1, positioning portions are provided at a plurality of positions in the circumferential direction of the outer peripheral surface of a stator, and fastening bolts inserted into the positioning portions are fastened to the housing to fix the stator to the housing.

[0003] JP 2022-60787 A

[0004] A known method for fixing a stator to a housing that houses a motor without using fastening bolts is to perform a shrink fit, in which the housing is heated to expand it, the stator is inserted, and the outer periphery of the stator comes into contact with the inner periphery of the housing.

[0005] However, if the outer periphery of the stator is brought into contact with the inner periphery of the housing by shrink fitting, 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 contact each other becomes large, it becomes difficult to ensure a sufficient area for the refrigerant flow path to circulate the refrigerant that has flowed into the housing to the compressor.

[0006] The present disclosure has been made in consideration of the above 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.

[0007] 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 rotationally drives the compression section about the axis, the motor including a stator disposed inside the housing so as to extend along the axis, and a rotor disposed on an inner circumferential side of the stator, the stator having an outer circumferential portion and a plurality of teeth disposed at a plurality of positions circumferentially around the axis so as to protrude from the outer circumferential portion toward the axis, and around which a coil winding is wound, has a first notch formed at a first position included in the plurality of circumferential positions where the plurality of tooth portions are arranged, and a second notch formed at a second position included in the plurality of circumferential positions where the plurality of tooth portions are arranged and has a circumferential length longer than that of the first notch, wherein the first position where the first notch is formed is a position sandwiched between areas where the outer circumferential portion contacts the inner circumferential surface of the housing, and the second position where the second notch is formed is a position sandwiched between areas where the outer circumferential portion and the inner circumferential surface of the housing do not contact, and where a refrigerant flow path through which the refrigerant circulates is formed on the inner circumferential surface.

[0008] According to the present disclosure, it is possible to provide an electric compressor that can reduce 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 can ensure a sufficient area for the refrigerant flow path.

[0009] It is a longitudinal sectional view showing a schematic configuration of a scroll compressor according to an embodiment of the present disclosure.It is a sectional view of the scroll compressor shown in Figure 1 taken along the line AA.It is a sectional view of the stator shown in Figure 2.

[0010] A scroll compressor (electric compressor) 100 according to an embodiment of the present disclosure will be described with reference to the drawings. The scroll compressor 100 of this embodiment is used in, for example, a vehicle air conditioner.

[0011] Fig. 1 is a vertical cross-sectional view showing a schematic configuration of a scroll compressor 100 according to this embodiment. As shown in Fig. 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 unit) 40, a motor 50, a bearing unit 60, an inverter 70, and a gasket 80.

[0012] The bearing housing 10, the rear housing 20, and the 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 an axis X1 that is the center of rotation of the orbiting scroll 42. The bearing housing 10 has an internal space that accommodates a bearing portion 60 and the scroll compression mechanism 40.

[0013] 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 communicates with 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.

[0014] The front housing 30 is provided with a suction port 31 for drawing in a refrigerant. Refrigerant supplied from the outside is introduced into the internal space of the front housing 30 through the suction 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 through the suction port 31 is a mixed refrigerant (fluid) containing lubricating oil and refrigerant gas.

[0015] The bearing housing 10 and the rear housing 20 are formed with insertion holes into which fastening bolts 90 are inserted. The end of the front housing 30 on the bearing housing 10 side is formed with fastening holes (not shown) into which male threads formed at the tip of the fastening bolts 90 are fastened. By fastening the fastening bolts 90 into the fastening holes formed in the front housing 30, 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.

[0016] The scroll compression mechanism 40 is a device that is disposed inside the bearing housing 10 and rotates about the axis X1 to compress the refrigerant gas. The scroll compression mechanism 40 has a fixed scroll 41 that is fixedly sandwiched 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 causing the orbiting scroll 42 to revolve relative to the fixed scroll 41 using the driving force of the motor 50.

[0017] The fixed scroll 41 has a spiral wrap (first wall) 41B that is a wall provided on one side of an 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.

[0018] The orbiting scroll 42 has a spiral wrap (second wall) 42B, which is a wall provided on one side of an end plate (second end plate) 42A. The orbiting scroll 42 is connected to an eccentric shaft (not shown) connected to a motor 50, and is supported so as to be capable of orbital rotation via a rotation-preventing mechanism (not shown). The orbiting scroll 42 is meshed with the spiral wrap 41B of the fixed scroll 41, and is supported so as to be capable of orbital rotation while being prevented from rotating.

[0019] 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 reaches or exceeds 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 then guided to the outside through a discharge port (not shown).

[0020] The motor 50 is a device that drives the orbiting scroll 42 of the scroll compression mechanism 40 to rotate about 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, details of the motor 50 will be described with reference to FIGS. 2 and 3. FIG. 2 is a cross-sectional view of the scroll compressor 100 shown in FIG. 1 taken along the line A-A. FIG. 3 is a cross-sectional view of the stator shown in FIG. 2. As shown in FIGS. 2 and 3, the motor 50 has a stator 51, a rotor 52 disposed on the inner circumferential side of the stator 51, and a drive shaft 53 connected to the rotor 52.

[0021] The stator 51 is formed by laminating a predetermined number of electromagnetic steel plates that have been stamped 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 FIGS. 2 and 3 , a plurality of teeth 51 a are provided on the inner periphery of the stator 51. A coil winding (not shown) is wound around each of the plurality of teeth 51 a via a bobbin (not shown).

[0022] As shown in Fig. 3, the stator 51 has a plurality of teeth 51a and an outer circumferential portion 51b to which the teeth 51a are connected. The outer circumferential portion 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 circumferential portion 51b toward the axis X1.

[0023] 2 and 3, the outer peripheral portion 51b has first notches 51c1 formed at positions P1, P2, P4, P5, P7, and P8 (first positions) included in the plurality of positions P1 to P9 in the circumferential direction CD where the plurality of teeth 51a are arranged, and second notches 51c2 formed at positions P3, P6, and P9 (second positions) included in the plurality of positions P1 to P9 in the circumferential direction CD where the plurality of teeth 51a are arranged. A length L2 (second length) of the second notch 51c2 in the circumferential direction CD is longer than a length L1 (first length) of the first notch 51c1 in the circumferential direction CD.

[0024] The first notches 51c1 and the second notches 51c2 are arranged at equal intervals along the circumferential direction CD at multiple positions where the teeth 51a are arranged (nine positions P1, P2, P3, P4, P5, P6, P7, and P8 shown in FIG. 2). The second notches 51c2 are arranged at three positions P3, P6, and P9 at intervals of 120 degrees.

[0025] 2 , in the circumferential direction CD, the region between position C1 and position C2, the region between position C3 and position C4, and the region between position C5 and position C6 are regions where the outer peripheral portion 51b of the stator 51 contacts the inner peripheral surface 30a of the front housing 30. Positions P1, P2, P4, P5, P7, and P8 where the first cutout portions 51c1 are formed are positions sandwiched between the regions where the outer peripheral portion 51b contacts the inner peripheral surface 30a of the front housing 30.

[0026] Positions P1 and P2 are located between the contact areas between positions C1 and C2 of the outer circumferential portion 51b of the stator 51 and the inner circumferential surface 30a of the front housing 30. Positions P4 and P5 are located between the contact areas between positions C3 and C4 of the outer circumferential portion 51b of the stator 51 and the inner circumferential surface 30a of the front housing 30. Positions P7 and P8 are located between the contact areas between positions C5 and C6 of the outer circumferential portion 51b of the stator 51 and the inner circumferential surface 30a of the front housing 30.

[0027] Position P3 is a position sandwiched between regions where the outer peripheral portion 51b and the inner peripheral surface 30a of the front housing 30 do not contact each other (region from position C2 to position C3), and where refrigerant flow path 10b through which refrigerant gas flows is formed on the inner peripheral surface 30a. Position P6 is a position sandwiched between regions where the outer peripheral portion 51b and the inner peripheral surface 30a of the front housing 30 do not contact each other (region from position C4 to position C5), and where refrigerant flow path 30b through which refrigerant gas flows is formed on the inner peripheral surface 30a. Position P9 is a position sandwiched between regions where the outer peripheral portion 51b and the inner peripheral surface 30a of the front housing 30 do not contact each other (region from position C6 to position C1), and where refrigerant flow path 10b through which refrigerant gas flows is formed on the inner peripheral surface 30a.

[0028] 3, the length L1 of the first notch 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 notch 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.

[0029] The bearing 60 is a member that supports a rotating shaft (not shown) that rotates about the axis X1 by the motor 50. An eccentric shaft that is disposed eccentrically with respect to the axis X1 is provided at the end of the rotating shaft on the scroll compression mechanism 40 side.

[0030] The inverter 70 is a device that generates a drive voltage for driving the motor 50 and controls the rotation speed of the motor 50 .

[0031] The gasket 80 is a member that is arranged 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 sealing area to prevent refrigerant from leaking out from between the end face 10a and the end face 20a.

[0032] The following describes the operation and effects of the scroll compressor 100 of the present embodiment. According to the scroll compressor 100 of the present embodiment, positions P1, P2, P4, P5, P7, and P8 of the first notches 51c1 formed in the outer circumferential portion 51b of the stator 51 are located between regions where the outer circumferential portion 51b of the stator 51 contacts the inner circumferential surface 30a of the front housing 30. Therefore, vibrations of the teeth 51a located at positions P1, P2, P4, P5, P7, and P8 are transmitted to the inner circumferential surface 30a of the front housing 30 via the outer circumferential portion 51b. Meanwhile, because the first notches 51c1 are located at positions P1, P2, P4, P5, P7, and P8 in the circumferential direction CD where the teeth 51a are located, vibrations transmitted directly from the teeth 51a to the inner circumferential surface 30a of the front housing 30 can be reduced compared to a case where the first notches 51c1 are not located.

[0033] Furthermore, in the scroll compressor 100 of this embodiment, the positions P3, P6, and P9 of the second cutouts 51c2 formed in the outer circumferential portion 51b of the stator 51 are sandwiched between regions where the outer circumferential portion 51b of the stator 51 does not contact the inner circumferential surface 30a of the front housing 30, and are positions where the refrigerant flow paths 30b through which the refrigerant flows are formed on the inner circumferential surface 30a. Because the second cutouts 51c2 are located at the positions P3, P6, and P9 in the circumferential direction CD where the teeth 51a are located, a sufficient area of ​​the refrigerant flow path can be secured compared to a case where the second cutouts 51c2 are not located.

[0034] In the scroll compressor 100 of this embodiment, the length L1 of the first cutout portion 51c1 in the circumferential direction CD is shorter than the length L3 of the inner peripheral end portion of the tooth portion 51a in the circumferential direction CD. This ensures a sufficient area for contact between the outer peripheral portion 51b of the stator 51 and the inner peripheral surface 30a of the front housing 30, thereby ensuring a sufficient holding force for the inner peripheral surface 30a of the front housing 30 to hold the stator 51.

[0035] Furthermore, in the scroll compressor 100 of this embodiment, the length L2 of the second cutout portion 51c2 in the circumferential direction CD is longer than the length L3 of the inner peripheral end portion of the tooth portion 51a in the circumferential direction CD. Therefore, a sufficient area of ​​the refrigerant flow path 30b can be secured in the region where the outer peripheral portion 51b of the stator 51 does not contact the inner peripheral surface 30a of the front housing 30.

[0036] Furthermore, 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 at equal intervals and in a balanced manner radially outside the tooth portion 51a, and therefore, the vibration of the tooth portion 51a can be averaged and reduced compared to when they are arranged in an unbalanced manner.

[0037] The electric compressor according to the present embodiment described above can be understood as follows, for example. 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 circumferential side of the stator, the stator having an outer circumferential portion (51 b) and a plurality of teeth (51 a) disposed at a plurality of positions in a circumferential direction (CD) about 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 plurality of circumferential positions where the plurality of tooth portions are arranged, and a second notch (51c2) formed at a second position (P3, P6, P9) included in the plurality of circumferential positions where the plurality of tooth 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 areas where the outer circumferential portion contacts the inner circumferential surface of the housing, and the second position where the second notch is formed is a position sandwiched between areas where the outer circumferential portion and the inner circumferential surface of the housing do not contact, and where a refrigerant flow path (10b) through which the refrigerant flows is formed on the inner circumferential surface.

[0038] In the electric compressor according to the first aspect of the present disclosure, the first positions of the first notches formed in the outer peripheral portion of the stator are located between the regions where the outer peripheral portion of the stator contacts the inner peripheral surface of the housing. Therefore, vibrations of the teeth located at the first positions are transmitted to the inner peripheral surface of the housing via the outer peripheral portion. Meanwhile, because the first notches are located at the first circumferential positions where the teeth are located, vibrations transmitted directly from the teeth to the inner peripheral surface of the housing can be reduced compared to when the first notches are not located.

[0039] In the electric compressor according to the first aspect of the present disclosure, the second position of the second notch formed in the outer circumferential portion of the stator is located between areas where the outer circumferential portion of the stator and the inner circumferential surface of the housing do not contact each other, and is a position where a refrigerant flow path through which the refrigerant flows is formed on the inner circumferential surface. Because the second notch is located at the second circumferential position where the teeth are located, it is possible to ensure a sufficient area of ​​the refrigerant flow path compared to when the second notch is not located.

[0040] According to a second aspect of the present disclosure, the electric compressor of the first aspect further includes the following configuration: a first circumferential length (L1) of the first notch portion is shorter than a circumferential length (L3) of an inner peripheral end of the tooth portion, and a second circumferential length (L2) of the second notch portion is longer than the circumferential length of the inner peripheral end of the tooth portion.

[0041] In 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 peripheral end of the tooth, thereby ensuring a sufficient area for contact between the outer circumferential portion of the stator and the inner circumferential surface of the housing, thereby ensuring a sufficient holding force between the inner circumferential surface of the housing and the stator.

[0042] 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 peripheral end of the tooth, thereby ensuring a sufficient area for the refrigerant flow path in the region where the outer circumferential portion of the stator does not contact the inner circumferential surface of the housing.

[0043] According to a third aspect of the present disclosure, in the electric compressor of the first or second aspect, the plurality of first notches and the plurality of second notches are arranged at equal intervals along the circumferential direction.

[0044] According to the electric compressor of the third aspect of the present disclosure, the multiple first notches and second notches are each arranged in a balanced manner at equal intervals along the circumferential direction radially outside the tooth portion, thereby making it possible to average out and reduce vibrations of the tooth portion compared to when they are arranged unbalanced.

[0045] REFRIGERATED SYMBOLS 10 Bearing housing 10a End face 10b Refrigerant flow path 20 Rear housing 20a End face 30 Front housing 30a Inner peripheral surface 30b Refrigerant flow path 31 Intake port 40 Scroll compression mechanism (compression section) 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

1. A compressor comprising: 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 for driving the compression section to rotate about the axis, wherein the motor comprises: a stator disposed inside the housing so as to extend along the axis; and a rotor disposed on the inner peripheral side of the stator, wherein the stator has an outer circumferential portion, and a plurality of teeth sections disposed at a plurality of positions in the circumferential direction about the axis so as to protrude from the outer circumferential portion towards the axis, and around which a coil winding is wound, wherein the outer circumferential portion has: a first notch formed at a first position included in the plurality of circumferential positions where the plurality of teeth sections are disposed; and a second notch formed at a second position included in the plurality of circumferential positions where the plurality of teeth sections are disposed, the second notch having a longer length in the circumferential direction than the first notch, wherein the first position at which 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, 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.

2. An electric compressor as described in claim 1, wherein a first circumferential length of the first notch is shorter than the circumferential length of the inner circumferential end of the tooth, and a second circumferential length of the second notch is longer than the circumferential length of the inner circumferential end of the tooth.

3. An electric compressor according to claim 1 or 2, wherein the plurality of first cutouts and the plurality of second cutouts are disposed at equal intervals along the circumferential direction.

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