Electric compressor

Abstract

To suppress occurrence of resonance in an inverter case during operation of an electric compressor.SOLUTION: An electric compressor 1 includes an electric motor 4, a compression mechanism 5 driven by the electric motor 4, an inverter 6 for driving the electric motor 4, a motor housing 20 for housing the electric motor 4, an inverter case 7 for housing the inverter 6, and at least one first bolt 51 and at least one second bolt 52 for abutting and fixing the inverter case 7 to the motor housing 20. The motor housing 20 has a cylindrical body 24, and a flange 130 formed on a front end surface 24a (one end surface) of the body 24. The front end surface 24a of the body 24 and the flange 130 come into contact with the inverter case 7. The first bolt 51 fixes the inverter case 7 to the body 24. The second bolt 52 fixes the inverter case 7 to the flange 130.SELECTED DRAWING: Figure 20

Description

[Technical field]

[0001] The present invention relates to an electric compressor. [Background technology]

[0002] Many of the electric compressors used to compress refrigerant in vehicle air conditioners have an electric motor that drives a compression mechanism and an inverter. The electric motor is driven by controlling the power supply to the electric motor while converting DC power from an on-board battery or the like into AC power by the inverter. In this regard, Patent Document 1 discloses that a motor housing that houses the electric motor and an inverter case that houses the inverter are butted against each other in the axial direction of the electric compressor and fixed together. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-138248 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, the voltage of electric vehicles has been increasing. Accordingly, in order to secure the insulation distance at high voltage, the electronic circuit board of the inverter has been increasing in size, and as a result, the inverter case has also become larger. As a result, the inverter case protrudes significantly from the outline of the motor housing when viewed in the axial direction of the electric compressor. This protruding portion of the inverter case has low bending rigidity and a low natural frequency, so there is a risk of resonance occurring during operation of the electric compressor. Furthermore, this resonance may lead to damage to the inverter.

[0005] SUMMARY OF THE PRESENT EMBODIMENTS In view of the above, an object of the present invention is to suppress the occurrence of resonance in an inverter case during operation of an electric compressor. [Means for solving the problem]

[0006] According to one aspect of the present invention, there is provided an electric compressor. The electric compressor includes an electric motor, a compression mechanism driven by the electric motor, an inverter driving the electric motor, a motor housing accommodating the electric motor, an inverter case accommodating the inverter, and at least one first bolt and at least one second bolt for abutting and fixing the inverter case to the motor housing. The motor housing has a cylindrical main body and a flange portion formed on one end face of the main body. The end face of the main body and the flange portion abut against the inverter case. The first bolt fixes the inverter case to the main body. The second bolt fixes the inverter case to the flange portion. Effect of the Invention

[0007] According to the present invention, it is possible to suppress the occurrence of resonance in the inverter case during operation of the electric compressor. [Brief description of the drawings]

[0008] [Figure 1] 1 is a schematic vertical sectional view of an electric compressor according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a view taken along the line AA in FIG. [Diagram 3] FIG. 2 is a front view of the electric compressor according to the first embodiment. [Figure 4] FIG. 2 is a bottom view of the electric compressor according to the first embodiment. [Diagram 5] FIG. 2 is a front view of a motor housing in the first embodiment. [Figure 6] FIG. 4 is a perspective view of a connecting member in the first embodiment. [Figure 7] FIG. 11 is a perspective view of a connecting member according to a second embodiment of the present invention. [Figure 8] FIG. 11 is a perspective view of a connecting member according to a third embodiment of the present invention. [Figure 9]FIG. 13 is a perspective view of a connecting member according to a fourth embodiment of the present invention. [Figure 10] FIG. 13 is a diagram showing an attachment state of a connecting member in the fourth embodiment, as viewed from behind. [Figure 11] FIG. 13 is a diagram showing an attachment state of a connecting member as viewed from below in the fourth embodiment. [Figure 12] 13A to 13C are diagrams illustrating a rotation stop function of a connecting member in the fourth embodiment. [Figure 13] FIG. 11 is a schematic vertical sectional view of an electric compressor according to a fifth embodiment of the present invention. [Figure 14] FIG. 14 is a view taken along the arrow BB in FIG. [Figure 15] FIG. 13 is a bottom view of the electric compressor in the fifth embodiment. [Figure 16] FIG. 13 is a diagram showing a modified example of the electric compressor of the fifth embodiment. [Figure 17] FIG. 13 is a left side view of an electric compressor according to a sixth embodiment of the present invention. [Figure 18] FIG. 13 is a schematic vertical sectional view of the electric compressor according to the sixth embodiment. [Figure 19] FIG. 19 is a view taken along the arrow CC in FIGS. 17 and 18. [Figure 20] FIG. 13 is a front view of the electric compressor according to the sixth embodiment. [Figure 21] FIG. 23 is a front view of the motor housing in the sixth embodiment. [Figure 22] FIG. 13 is a diagram showing a modified example of the electric compressor of the sixth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0010] Fig. 1 is a schematic vertical cross-sectional view of an electric compressor 1 in a first embodiment of the present invention. Fig. 2 is a view taken along the line AA in Fig. 1. Figs. 3 and 4 are a front view and a bottom view, respectively, of the electric compressor 1. Fig. 5 is a front view of a motor housing 20. In Fig. 2, components inside the motor housing 20 are omitted for the sake of simplicity. In the following, the electric compressor 1 will be described with the front / rear, left / right, and top / bottom defined as shown in Figs. 1 and 2 for the sake of convenience.

[0011] The electric compressor 1 may be configured, for example, to be mounted on a vehicle to constitute a part of a refrigerant circuit of an air conditioner for a vehicle, and to compress and discharge a refrigerant (a gaseous refrigerant in this embodiment).

[0012] The electric compressor 1 has a housing 2, a rotating shaft 3, an electric motor 4 that rotates the rotating shaft 3, a compression mechanism 5 that is driven by the rotating shaft 3 and compresses a refrigerant, an inverter 6 that drives the electric motor 4, and an inverter case 7. The rotating shaft 3, the electric motor 4, and the compression mechanism 5 are housed in the housing 2. Here, the electric motor 4 and the compression mechanism 5 are arranged in series in the axial direction of the rotating shaft 3 (the axial direction of the electric compressor 1) within the housing 2. The inverter 6 is housed in the inverter case 7.

[0013] In this embodiment, the electric compressor 1 is an electric scroll compressor, and the compression mechanism 5 is a scroll compression mechanism. The compression mechanism 5 includes a fixed scroll 8 and an orbiting scroll (movable scroll) 9 that orbits relative to the fixed scroll 8. The fixed scroll 8 and the orbiting scroll 9 are disposed opposite to each other in the axial direction of the electric compressor 1.

[0014] The orbiting scroll 9 is driven by the rotating shaft 3 via a crank mechanism 10 and configured to perform orbital motion relative to the fixed scroll 8 , in other words, to revolve around the axis of the fixed scroll 8 .

[0015] The crank mechanism 10 connects the rotating shaft 3 and the orbiting scroll 9, and is configured to convert the rotational motion of the rotating shaft 3 into the orbiting motion of the orbiting scroll 9. The compression mechanism 5 is configured so that the orbiting scroll 9 orbits relative to the fixed scroll 8, thereby taking in and compressing a low-pressure refrigerant.

[0016] The housing 2 is made of, for example, metal. The housing 2 includes a motor housing 20, also referred to as a front housing, and a rear housing 21. The motor housing 20 (main body portion 24 described later) accommodates the rotating shaft 3 and the electric motor 4. The rear housing 21 (front tubular portion 25 described later) accommodates the compression mechanism 5. The housing 2 is configured by abutting a rear end surface of the motor housing 20 (rear end surface 24b described later) against a front end surface of the rear housing 21 (front end surface 25a described later) and fastening them together with a fastener (not shown) or the like.

[0017] The main body 24 of the motor housing 20 is tubular and extends in the front-rear direction (horizontal direction), and in this embodiment is cylindrical in particular. The main body 24 has a front end face (one end face) 24a that is closed and a rear end face (the other end face) 24b that is open.

[0018] The rear housing 21 is cylindrical with two sections, front and rear. The rear housing 21 has a cylindrical front tube portion 25 having an outer diameter equal to that of the main body portion 24 of the motor housing 20, and a cylindrical rear tube portion 26 having an outer diameter smaller than that of the front tube portion 25. A front end surface 25a of the front tube portion 25 is open. A rear end surface 26b of the rear tube portion 26 is closed. The front tube portion 25 and the rear tube portion 26 may be separate members.

[0019] The electric motor 4 is configured as, for example, a three-phase synchronous motor (brushless DC motor), and includes a stator core unit 13 and a rotor 14.

[0020] The stator core unit 13 is fixed to an inner circumferential surface of a main body 24 of the motor housing 20. A direct current from an in-vehicle battery (not shown) or the like is converted into a three-phase alternating current by an inverter 6 and supplied to the stator core unit 13.

[0021] The rotor 14 is disposed radially inside the stator core unit 13 with a predetermined gap therebetween. A permanent magnet (not shown) is incorporated in the rotor 14. The rotor 14 is formed in a cylindrical shape, and is fixed to the rotating shaft 3 with the rotating shaft 3 inserted into its hollow portion. In other words, the rotor 14 is integrated with the rotating shaft 3.

[0022] When a magnetic field is generated in the stator core unit 13 by the power supply from the inverter 6, a torque acts on the permanent magnet of the rotor 14, causing the rotor 14 to rotate, thereby rotating the rotating shaft 3.

[0023] A suction port P1 is formed adjacent to the front end surface 24a in an upper portion of the main body 24 of the motor housing 20. The suction port P1 is connected to the refrigerant circuit (the low pressure side) via a connecting pipe or the like (not shown).

[0024] As shown in FIG. 1, in this embodiment, the electric compressor 1 has a suction chamber H1 into which a low-pressure refrigerant flows, a compression chamber H2 that compresses the low-pressure refrigerant, and a discharge chamber H3 from which the refrigerant compressed in the compression chamber H2 is discharged.

[0025] The suction chamber H1 is defined by the main body 24 of the motor housing 20. Low-pressure refrigerant from the refrigerant circuit flows into the suction chamber H1 through the suction port P1. The low-pressure refrigerant in the suction chamber H1 passes through a refrigerant passage L1 and reaches a space H4 near the compression mechanism 5.

[0026] The compression chamber H2 is formed in the compression mechanism 5, i.e., between the fixed scroll 8 and the orbiting scroll 9. The compression mechanism 5 is configured to compress the low-pressure refrigerant by taking in the low-pressure refrigerant from the space H4 when the compression chamber H2 is formed.

[0027] The discharge chamber H3 is disposed in the rear cylindrical portion 26 of the rear housing 21. A discharge hole L2 that communicates the compression chamber H2 and the discharge chamber H3 is formed in the base plate 8a of the fixed scroll 8. Therefore, the refrigerant compressed in the compression chamber H2 of the compression mechanism 5 is discharged through the discharge hole L2 to the discharge chamber H3. A check valve 15, for example a reed valve, is attached to the surface of the base plate 8a of the fixed scroll 8 facing the discharge chamber H3. The check valve 15 allows the refrigerant to flow from the compression chamber H2 to the discharge chamber H3 but restricts the flow of the refrigerant from the discharge chamber H3 to the compression chamber H2.

[0028] An oil separator 16 that separates lubricating oil contained in the refrigerant (gaseous refrigerant) is disposed in the discharge chamber H3. A discharge port P2 is formed in an upper portion of the rear cylindrical portion 26 of the rear housing 21 so as to communicate with the discharge chamber H3 (oil separator 16). The discharge port P2 is connected to the refrigerant circuit (the high pressure side) via a connecting pipe (not shown). Therefore, the lubricating oil is separated from the refrigerant that has flowed into the discharge chamber H3 by the oil separator 16, and then the refrigerant is discharged from the discharge port P2 to the high pressure side of the refrigerant circuit.

[0029] Therefore, low-pressure refrigerant from the refrigerant circuit flows into the suction chamber H1 through the suction port P1, passes through the gap of the electric motor 4, and is then guided to the space H4 near the compression mechanism 5 through the refrigerant passage L1. The low-pressure refrigerant guided to the space H4 is taken into the compression chamber H2 of the compression mechanism 5 as the orbiting scroll 9 orbits, and is compressed. The refrigerant compressed in the compression chamber H2 is discharged into the discharge chamber H3 through the discharge hole L2 (and the check valve 15), and then the lubricating oil is separated in the oil separator 16. The refrigerant from which the lubricating oil has been separated in the oil separator 16 is then discharged from the discharge port P2 to the refrigerant circuit.

[0030] Here, the front end surface 24a of the main body 24 of the motor housing 20 and the electric motor 4 (the stator core unit 13 and the rotor 14) can be cooled by the low-temperature, low-pressure refrigerant flowing into the suction chamber H1 via the suction port P1. The compression mechanism 5 driven by the electric motor 4 is configured to compress and discharge the refrigerant drawn into the main body 24 of the motor housing 20 (into the suction chamber H1) from the suction port P1.

[0031] In this embodiment, one or more protrusions 27 are provided on the upper part of the housing 2 (at least one of the upper part of the motor housing 20 and the upper part of the rear housing 21). The protrusions 27 can be used to fix the housing 2 to the vehicle. The protrusions 27 protrude upward from the upper part of the housing 2 (at least one of the upper part of the motor housing 20 and the upper part of the rear housing 21). The protrusions 27 can be, for example, rectangular parallelepiped (prism-shaped) or cylindrical.

[0032] The inverter case 7 is made of, for example, metal. The inverter case 7 is disposed in front of the main body portion 24 of the motor housing 20. The inverter case 7 is fixed to the main body portion 24 of the motor housing 20 by being in contact with the main body portion 24.

[0033] The inverter case 7 has an end wall (bottom wall) 30 and a peripheral wall 31 that rises from the periphery of the end wall 30 and defines an opening that faces the end wall 30. In this embodiment, the inverter case 7 is a rectangular box extending in the vertical direction, and the rear end of the inverter case 7 is formed by the end wall 30. An inverter cover 32 for closing the opening is detachably attached to the front end of the inverter case 7. A plurality of bolts 33 (12 in this embodiment) are used to fix the inverter cover 32 to the inverter case 7.

[0034] When viewed in the axial direction of the electric compressor 1, the inverter case 7 protrudes upward, downward, left, and right from the contour of the main body 24 of the motor housing 20. In particular, in this embodiment, when viewed in the axial direction of the electric compressor 1, the inverter case 7 protrudes significantly downward from the contour of the main body 24 of the motor housing 20.

[0035] The outer surface 30a of the end wall 30 of the inverter case 7 is made up of a contact portion 30a1 that contacts the front end surface 24a of the main body portion 24 of the motor housing 20, and an exposed portion 30a2 that is exposed to the outside.

[0036] The inverter 6 housed in the inverter case 7 has a plurality of switching elements (power switching elements) 35 (six in this embodiment) and a control board 36 on which a control circuit for controlling the switching elements 35 is mounted. The control board 36 is disposed in the inverter case 7 at a position away from the end wall 30 towards the opening. The control board 36 is attached to the inverter case 7 by a mounting member (not shown). The switching elements 35 are provided on a portion of the inner surface 30b of the end wall 30 of the inverter case 7 adjacent to the abutment portion 30a1 (in other words, adjacent to the front end surface 24a of the main body 24).

[0037] A plurality of (eight in this embodiment) first bolts 51 are used to fix the inverter case 7 to the main body 24 of the motor housing 20. For this purpose, a plurality of (eight in this embodiment) through holes 38 are formed in the end wall 30 of the inverter case 7 for inserting the male threads of the first bolts 51. In addition, a plurality of (eight in this embodiment) female threads 24c into which the male threads of the first bolts 51 are screwed are formed in the main body 24 (front end surface 24a) of the motor housing 20. Therefore, the first bolts 51 are screwed in from the inside of the inverter case 7. Here, the above-mentioned bolt 33 and the first bolts 51 are both screwed in from the front to the rear (i.e., in the same direction). In this embodiment, a plurality of (eight in this embodiment) first bolts 51 are arranged at intervals from each other along the circumferential direction of the main body 24.

[0038] In this embodiment, one or more protrusions 39 are provided on the upper part of the inverter case 7. The protrusions 39 can be used to fix the inverter case 7 to a vehicle. The protrusions 39 protrude upward from the upper part of the inverter case 7. The protrusions 39 can be, for example, rectangular or cylindrical.

[0039] In this embodiment, when viewed in the axial direction of the electric compressor 1, the inverter case 7 significantly protrudes downward from the contour of the main body 24 of the motor housing 20. This causes the inverter case 7 to be in a so-called cantilevered state. In order to reduce this cantilevered state, in this embodiment, the motor housing 20 and the inverter case 7 have a first protrusion 41 and a second protrusion 42, respectively.

[0040] The first protrusion 41 is provided at a lower end of the outer circumferential surface of the main body 24 of the motor housing 20, and protrudes downward from the lower end. That is, the first protrusion 41 protrudes radially outward from the outer circumferential surface of the main body 24 of the motor housing 20. The second protrusion 42 is provided at a height position lower than the first protrusion 41 in the exposed portion 30a2 of the outer surface 30a of the end wall 30 of the inverter case 7, and protrudes rearward from that position. In this embodiment, the first protrusion 41 and the second protrusion 42 are each rectangular parallelepiped-shaped, but may also be cylindrical.

[0041] In this embodiment, the first protrusion 41 is indirectly fixed to the second protrusion 42 via a connecting member 100. Here, the connecting member 100 will be described with reference to FIG. 6 in addition to the above-mentioned FIGS. 1 to 5. FIG. 6 is a perspective view of the connecting member 100.

[0042] The connecting member 100 includes a main portion 101 having a rectangular plate shape extending in one direction, a first mounting portion 111 having a rectangular plate shape formed at one end of the main portion 101, and a second mounting portion 112 having a rectangular plate shape formed at the other end of the main portion 101. In this embodiment, the main portion 101, the first mounting portion 111, and the second mounting portion 112 can be formed by, for example, bending a single metal plate.

[0043] The first mounting portion 111 is in surface contact with the lower end surface of the first protruding portion 41. A bolt 121 is used to fix the first mounting portion 111 to the first protruding portion 41. For this purpose, a through hole 113 is formed in the first mounting portion 111 for inserting the male thread portion of the bolt 121. The first protruding portion 41 is formed with a female thread portion 43 into which the male thread portion of the bolt 121 screws.

[0044] The second mounting portion 112 is in surface contact with the rear end surface of the second protruding portion 42. A bolt 122 is used to fix the second mounting portion 112 to the second protruding portion 42. For this reason, the second mounting portion 112 is formed with a through hole 114 for inserting the male thread portion of the bolt 122. The second protruding portion 42 is formed with a female thread portion 44 into which the male thread portion of the bolt 122 screws.

[0045] In this embodiment, from the viewpoint of reducing the cantilevered state of the inverter case 7 described above, it is preferable that the second protrusion 42 is provided at a position as far downward as possible from the first protrusion 41. Furthermore, it goes without saying that in order to use a plurality of connecting members 100, the first protrusion 41 and the second protrusion 42 may be provided so as to correspond to each connecting member 100. In other words, the electric compressor 1 may include a plurality of connecting members 100, a plurality of first protrusions 41, and a plurality of second protrusions 42.

[0046] According to this embodiment, the electric compressor 1 includes an electric motor 4, a compression mechanism 5 driven by the electric motor 4, an inverter 6 that drives the electric motor 4, a motor housing 20 that houses the electric motor 4, and an inverter case 7 that is fixed in contact with the motor housing 20 and houses the inverter 6. The motor housing 20 has a cylindrical main body 24 and a first protrusion 41 provided on the outer circumferential surface of the main body 24. The inverter case 7 has an end wall 30, and the outer surface 30a of the end wall 30 includes an abutment portion 30a1 that abuts against the front end surface 24a (one end surface) of the main body 24, and an exposed portion 30a2 that is exposed to the outside. The exposed portion 30a2 of the outer surface 30a of the end wall 30 is provided with a second protrusion 42. The first protrusion 41 is indirectly fixed to the second protrusion 42 via a connecting member 100. This makes it possible to suppress the occurrence of resonance in the inverter case 7 during operation of the electric compressor 1. It is preferable that at least one of the first protrusion 41 and the second protrusion 42 has a rectangular parallelepiped or cylindrical shape.

[0047] Furthermore, according to the present embodiment, the connecting member 100 includes a first mounting portion 111 that is in surface contact with the first protruding portion 41, and a second mounting portion 112 that is in surface contact with the second protruding portion 42. The first mounting portion 111 is fixed to the first protruding portion 41. The second mounting portion 112 is fixed to the second protruding portion 42. This allows the connecting member 100 to be configured with a simple structure.

[0048] According to this embodiment, the main body 24 is formed with a suction port P1 adjacent to the front end surface 24a (one end surface). The compression mechanism 5 is configured to compress and discharge the refrigerant drawn into the main body 24 from the suction port P1. A switching element 35 constituting the inverter 6 is provided in a portion of the inner surface 30b of the end wall 30 adjacent to the abutting portion 30a1. Therefore, the switching element 35 can be cooled via the front end surface 24a of the main body 24 and the end wall 30 of the inverter case 7 by the low-temperature, low-pressure refrigerant flowing into the main body 24 via the suction port P1.

[0049] According to the present embodiment, the electric compressor 1 is mounted on a vehicle. The main body 24 extends horizontally. The inverter case 7 extends vertically. A protrusion 39 for fixing to the vehicle is provided on the upper part of the inverter case 7. The inverter case 7 protrudes downward from the main body 24. A first protrusion 41 is provided on the lower end of the outer circumferential surface of the main body 24. A second protrusion 42 is provided on the exposed portion 30a2 of the outer surface 30a of the end wall 30 at a height position lower than the first protrusion 41. This can reduce the cantilever state of the inverter case 7 described above. Here, the main body 24 is cylindrical, and the first protrusion 41 protrudes radially outward from the outer circumferential surface of the main body 24.

[0050] Next, a second embodiment of the present invention will be described with reference to Fig. 7. Fig. 7 is a perspective view of a connecting member 100 in this embodiment. Differences from the first embodiment described above will be described.

[0051] In this embodiment, the connecting member 100 further includes a pair of left and right reinforcing portions 102. Each reinforcing portion 102 is provided on the inner side of the bent connecting member 100 (main portion 101, first mounting portion 111, and second mounting portion 112) so as to suppress deformation of the bent connecting member 100 (main portion 101, first mounting portion 111, and second mounting portion 112). The reinforcing portions 102 are provided upright on both left and right edges of each of the main portion 101, first mounting portion 111, and second mounting portion 112 that constitute the connecting member 100.

[0052] Particularly, according to the present embodiment, the connecting member 100 further includes a pair of left and right reinforcing portions 102. This increases the rigidity of the connecting member 100, and further suppresses the occurrence of resonance in the inverter case 7 during operation of the electric compressor 1.

[0053] Next, a third embodiment of the present invention will be described with reference to Fig. 8. Fig. 8 is a perspective view of a connecting member 100' in this embodiment. Differences from the first embodiment described above will be described.

[0054] In the connecting member 100' in this embodiment, the main portion 101 described above is omitted, and the first mounting portion 111 and the second mounting portion 112 are formed, for example, by bending a single metal plate at a right angle. A pair of left and right reinforcing portions 102' are provided at the corners which are the connecting portions between the first mounting portion 111 and the second mounting portion 112. Each reinforcing portion 102' is fixed to the corners by welding or the like so as to suppress deformation of the connecting member 100 (the first mounting portion 111 and the second mounting portion 112) which is bent at a right angle.

[0055] Particularly, according to the present embodiment, the connecting member 100' further includes a pair of left and right reinforcing portions 102'. This increases the rigidity of the connecting member 100', and further suppresses the occurrence of resonance in the inverter case 7 during operation of the electric compressor 1.

[0056] Next, a fourth embodiment of the present invention will be described with reference to Figs. 9 to 12. Fig. 9 is a perspective view of a connecting member 100" in this embodiment. Fig. 10 is a diagram showing an attachment state of the connecting member 100" in this embodiment, viewed from behind. Fig. 11 is a diagram showing an attachment state of the connecting member 100" in this embodiment, viewed from below. Fig. 12 is a diagram for explaining the rotation stop function of the connecting member 100" in this embodiment. Here, Fig. 10 corresponds to the above-mentioned Fig. 2. Differences from the above-mentioned first embodiment will be described.

[0057] In connecting member 100" of the present embodiment, first mounting portion 111 in connecting member 100 described above is provided with a rectangular plate-shaped extension portion 111a that comes into surface contact with the left side surface of first protrusion 41. A through hole 113' is formed in extension portion 111a of first mounting portion 111, into which the male threaded portion of bolt 121 is inserted. Incidentally, first protrusion 41 is formed with a female threaded portion (not shown) into which the male threaded portion of bolt 121 screws.

[0058] In this embodiment, the bolt 121 is screwed in from left to right. Meanwhile, the bolt 122 is screwed in from rear to front. In this regard, Fig. 12 illustrates a screwing direction D1 of the bolt 121, a rotation direction R1 of the bolt 121 when the bolt 121 is screwed in, a screwing direction D2 of the bolt 122, and a rotation direction R2 of the bolt 122 when the bolt 122 is screwed in.

[0059] When the bolt 121 is screwed in the screwing direction D1 (i.e., from left to right), the bolt 121 rotates clockwise (along the rotation direction R1). Accordingly, the connecting member 100" also attempts to rotate clockwise (along the rotation direction R1), but this rotation is prevented by the second mounting portion 112, which is in surface contact with the second protrusion 42. In other words, the second mounting portion 112 functions as a rotation stopper that prevents the connecting member 100" from rotating relative to the first protrusion 41 when the bolt 121 is tightened.

[0060] On the other hand, when the bolt 122 is screwed in the screwing direction D2 (i.e., from rear to front), the bolt 122 rotates clockwise (along the rotation direction R2). Accordingly, the connecting member 100" also attempts to rotate clockwise (along the rotation direction R2), but this rotation is prevented by the extension 111a of the first mounting portion 111, which is in surface contact with the first protrusion 41. In other words, the extension 111a of the first mounting portion 111 functions as a rotation stopper that prevents the connecting member 100" from rotating relative to the second protrusion 42 when the bolt 122 is tightened.

[0061] In particular, according to this embodiment, the first mounting portion 111 (extension portion 111a) is fixed to the first protrusion 41, and the second mounting portion 112 is fixed to the second protrusion 42 by bolt fastening with bolts 121, 122, respectively. Each of the first mounting portion 111 (extension portion 111a) and the second mounting portion 112 is configured to function as a rotation stopper that suppresses rotation of the connecting member 100" relative to the first protrusion 41 and the second protrusion 42 when the bolts 121, 122 are tightened. This allows the assembly work of the connecting member 100" to be performed efficiently.

[0062] Next, a fifth embodiment of the present invention will be described with reference to Figs. 13 to 15. Fig. 13 is a schematic vertical cross-sectional view of the electric compressor 1 in this embodiment. Fig. 14 is a view taken along the arrow BB in Fig. 13. Fig. 15 is a bottom view of the electric compressor 1 in this embodiment. In Fig. 13, similar to Fig. 2, components inside the motor housing 20 are omitted for the sake of simplicity. Differences from the first embodiment described above will be described.

[0063] In this embodiment, the second protrusion 42 is provided at a height position equivalent to that of the first protrusion 41 in the exposed portion 30a2 of the outer surface 30a of the end wall 30 of the inverter case 7, and protrudes rearward from that position. The first protrusion 41 is directly fixed to the second protrusion 42 by the bolt 123 with the front end surface of the first protrusion 41 abutting against the rear end surface of the second protrusion 42. For this reason, the first protrusion 41 is formed with a through hole 115 for inserting the male threaded portion of the bolt 123. The second protrusion 42 is formed with a female threaded portion 116 into which the male threaded portion of the bolt 123 is screwed. Therefore, the bolt 123 is screwed from the rear to the front.

[0064] Particularly, according to this embodiment, the first protrusion 41 abuts against the second protrusion 42. The first protrusion 41 is directly fixed to the second protrusion 42 by the bolt 123. This makes it possible to omit the above-mentioned connecting members 100, 100', 100".

[0065] FIG. 16 is a diagram showing a modified example of the electric compressor 1 of the present embodiment. In this modified example, a through hole 115' for inserting the male threaded portion of the bolt 123 is formed in the end wall 30 and the second protruding portion 42 of the inverter case 7. In addition, a female threaded portion 116' into which the male threaded portion of the bolt 123 is screwed is formed in the first protruding portion 41. Therefore, the bolt 123 is screwed from the inside of the inverter case 7. As described above, the first bolt 51 is also screwed from the inside of the inverter case 7. Furthermore, both the bolt 123 and the first bolt 51 are screwed from the front to the rear (i.e., in the same direction). Therefore, the operation of screwing the bolt 123 and the operation of screwing the first bolt 51 can be performed in a series of operations.

[0066] Examples of clauses that can be understood from the above-mentioned first to fifth embodiments and their modifications are described below.

[0067] [Clause 1] An electric motor; a compression mechanism driven by the electric motor; an inverter that drives the electric motor; a motor housing that accommodates the electric motor; an inverter case that is fixed to the motor housing in abutment therewith and that houses the inverter; An electric compressor comprising: The motor housing has a cylindrical main body and a first protrusion provided on an outer circumferential surface of the main body, the inverter case has an end wall, and an outer surface of the end wall includes a contact portion that contacts one end surface of the main body portion and an exposed portion that is exposed to the outside, the exposed portion of the outer surface of the end wall is provided with a second protrusion; The first protrusion is directly or indirectly fixed to the second protrusion. Electric compressor.

[0068] [Clause 2] The first protrusion abuts against the second protrusion, Item 2. The electric compressor of item 1, wherein the first protrusion is directly fixed to the second protrusion by a bolt.

[0069] [Clause 3] The electric compressor described in clause 1, wherein the first protrusion is indirectly fixed to the second protrusion via a connecting member.

[0070] [Article 4] the connecting member includes a first mounting portion in surface contact with the first protruding portion and a second mounting portion in surface contact with the second protruding portion, the first mounting portion is fixed to the first protrusion, 4. The electric compressor of claim 3, wherein the second mounting portion is fixed to the second protrusion.

[0071] [Article 5] the first mounting portion is fixed to the first protruding portion and the second mounting portion is fixed to the second protruding portion by bolt fastening, The electric compressor described in clause 4, wherein each of the first mounting portion and the second mounting portion is configured to function as a rotation stopper to suppress rotation of the connecting member relative to the first protrusion portion and the second protrusion portion when the bolt is tightened.

[0072] [Article 6] The electric compressor according to claim 4 or 5, wherein the connecting member further includes a reinforcing portion.

[0073] [Article 7] The main body has a suction port formed adjacent to the end surface, The compression mechanism is configured to compress and discharge a refrigerant drawn into the main body through the suction port, The electric compressor according to any one of clauses 1 to 6, wherein a switching element constituting the inverter is provided on a portion of the inner surface of the end wall adjacent to the contact portion.

[0074] [Article 8] The electric compressor is mounted on a vehicle, The body portion extends horizontally, The inverter case extends in a vertical direction, a protrusion for fixing the inverter case to the vehicle is provided on an upper portion of the inverter case, The electric compressor according to any one of clauses 1 to 7, wherein the inverter case protrudes downward beyond the main body portion.

[0075] [Article 9] The first protrusion is provided at a lower end of an outer circumferential surface of the main body, Clause 9. The electric compressor as described in clause 8, wherein the second protrusion is provided at a height position equal to or lower than the first protrusion on the exposed portion of the outer surface of the end wall.

[0076] [Article 10] The body portion is cylindrical, The electric compressor according to any one of clauses 1 to 9, wherein the first protrusion protrudes radially outward from an outer circumferential surface of the main body.

[0077] [Article 11] 11. The electric compressor according to any one of clauses 1 to 10, wherein at least one of the first protrusion and the second protrusion is rectangular parallelepiped-shaped or cylindrical-shaped.

[0078] Next, a sixth embodiment of the present invention will be described with reference to Figs. 17 to 21. Fig. 17 is a left side view of the electric compressor 1 in this embodiment. Fig. 18 is a schematic vertical cross-sectional view of the electric compressor 1 in this embodiment. Fig. 19 is a view taken along the CC arrow in Figs. 17 and 18. Fig. 20 is a front view of the electric compressor 1 in this embodiment. Fig. 21 is a front view of the motor housing 20 in this embodiment. Fig. 17 also shows a partial cross-section at a mounting location of a second bolt 52, which will be described later. In Fig. 19, similar to Fig. 2, components inside the motor housing 20 are omitted for the sake of simplicity. Differences from the first embodiment will be described.

[0079] In this embodiment, the first protrusion 41 and the second protrusion 42 are omitted. The motor housing 20 has a flange portion 130 in addition to the main body portion 24. The flange portion 130 is formed on the front end surface (one end surface) 24a of the main body portion 24. The flange portion 130 protrudes radially outward from the front end surface 24a of the main body portion 24. When viewed in the axial direction of the electric compressor 1, the flange portion 130 has a square outline that surrounds the outer circumferential surface of the main body portion 24 from the outside. When viewed in the axial direction of the electric compressor 1, it is preferable that the outer circumferential surface of the main body portion 24 is inscribed in the square outline of the flange portion 130. This makes it possible to keep the protrusion of the flange portion 130 from the outer circumferential surface of the main body portion 24 to a minimum.

[0080] In this embodiment, the front end surface 24a of the main body 24 of the motor housing 20 and the flange portion 130 abut against the outer surface 30a of the end wall 30 of the inverter case 7. In this embodiment, the inverter case 7 protrudes in all directions from the outline of the flange portion 130 of the motor housing 20 when viewed in the axial direction of the electric compressor 1.

[0081] In this embodiment, a plurality of (four in this embodiment) second bolts 52 are used to fix the inverter case 7 to the flange portion 130 of the motor housing 20. For this reason, a plurality of (four in this embodiment) through holes 38' are formed in the end wall 30 of the inverter case 7 for inserting the male threads of the second bolts 52. In addition, a plurality of (four in this embodiment) female threads 131 into which the male threads of the second bolts 52 are screwed are formed in the flange portion 130 of the motor housing 20. Therefore, the second bolt 52 is screwed from the inside of the inverter case 7. As described above, the first bolt 51 is also screwed from the inside of the inverter case 7. Furthermore, both the first bolt 51 and the second bolt 52 are screwed from the front to the rear (i.e., in the same direction). Therefore, the screwing operation of the first bolt 51 and the screwing operation of the second bolt 52 can be performed in a series of operations. In this embodiment, the second bolts 52 are disposed at the four corners of the flange portion 130 having a square outline.

[0082] Particularly, according to this embodiment, the electric compressor 1 includes an electric motor 4, a compression mechanism 5 driven by the electric motor 4, an inverter 6 that drives the electric motor 4, a motor housing 20 that accommodates the electric motor 4, an inverter case 7 that accommodates the inverter 6, and at least one first bolt 51 and at least one second bolt 52 for abutting and fixing the inverter case 7 to the motor housing 20. The motor housing 20 has a cylindrical main body 24 and a flange portion 130 formed on a front end surface 24a (one end surface) of the main body 24. The front end surface 24a of the main body 24 and the flange portion 130 abut against the inverter case 7. The first bolt 51 fixes the inverter case 7 to the main body 24. The second bolt 52 fixes the inverter case 7 to the flange portion 130. This makes it possible to suppress the occurrence of resonance in the inverter case 7 during operation of the electric compressor 1.

[0083] Furthermore, according to this embodiment, the main body 24 is cylindrical, and the flange portion 130 protrudes radially outward from the front end surface 24a (one end surface) of the main body 24. This increases the contact area of ​​the motor housing 20 with the inverter case 7 with a simple configuration, and allows them to be fastened together with bolts at multiple points.

[0084] According to this embodiment, the inverter case 7 has an end wall 30, and an outer surface 30a of the end wall 30 abuts against the front end surface 24a (one end surface) of the main body 24 and the flange portion 130. At least one through hole 38 is formed in the end wall 30. At least one female thread portion 24c is formed in the main body 24 (front end surface 24a). The male thread portion of the first bolt 51 is inserted into the through hole 38 of the end wall 30 and is screwed into the female thread portion 24c. This allows the first bolt 51 to be screwed in from inside the inverter case 7.

[0085] According to this embodiment, the inverter case 7 has an end wall 30, and an outer surface 30a of the end wall 30 abuts against the front end surface 24a (one end surface) of the main body 24 and the flange portion 130. At least one through hole 38' is formed in the end wall 30. At least one female thread portion 131 is formed in the flange portion 130. The male thread portion of the second bolt 52 is inserted into the through hole 38' of the end wall 30 and is screwed into the female thread portion 131 of the flange portion 130. This allows the second bolt 52 to be screwed in from inside the inverter case 7.

[0086] According to this embodiment, the main body 24 has a suction port P1 formed adjacent to the front end surface 24a (one end surface). The compression mechanism 5 is configured to compress and discharge the refrigerant sucked into the main body 24 from the suction port P1. The inverter case 7 has an end wall 30, and an outer surface 30a of the end wall 30 abuts against the front end surface 24a of the main body 24 and the flange portion 130. A switching element 35 constituting the inverter 6 is provided on a portion of the inner surface 30b of the end wall 30 adjacent to the front end surface 24a of the main body 24. Therefore, the switching element 35 can be cooled via the front end surface 24a of the main body 24 and the end wall 30 of the inverter case 7 by the low-temperature, low-pressure refrigerant flowing into the main body 24 via the suction port P1.

[0087] Furthermore, according to this embodiment, the electric compressor 1 is mounted on a vehicle. The main body 24 extends horizontally. The inverter case 7 extends vertically. A protrusion 39 for fixing the inverter case 7 to the vehicle is provided on the upper part of the inverter case 7. The inverter case 7 protrudes downward beyond the main body 24. In an electric compressor 1 having this configuration, it is possible to suppress the occurrence of resonance in the inverter case 7 when the electric compressor 1 is operating.

[0088] Fig. 22 is a diagram showing a modified example of the electric compressor 1 of this embodiment, and corresponds to Fig. 19 described above. In this modified example, a plurality of (four in this modified example) through holes (not shown) are formed in the flange portion 130. In addition, a plurality of (four in this modified example) female threaded portions (not shown) are formed in the end wall 30 of the inverter case 7. The male threaded portion of the second bolt 52 is inserted into the through hole of the flange portion 130 and is screwed into the female threaded portion of the end wall 30 of the inverter case 7. Therefore, the second bolt 52 is screwed from the rear to the front.

[0089] Examples of clauses that can be understood from the above-mentioned sixth embodiment and its modified examples are described below.

[0090] [Article 12] An electric motor; a compression mechanism driven by the electric motor; an inverter that drives the electric motor; a motor housing that accommodates the electric motor; an inverter case that houses the inverter; at least one first bolt and at least one second bolt for abutting and fixing the inverter case to the motor housing; An electric compressor comprising: The motor housing has a cylindrical main body and a flange portion formed on one end surface of the main body, the end surface of the main body and the flange portion are in contact with the inverter case, the first bolt fixes the inverter case to the main body; The second bolt fixes the inverter case to the flange portion. Electric compressor.

[0091] [Article 13] The body portion is cylindrical, 13. The electric compressor according to claim 12, wherein the flange portion protrudes radially outward from the end surface of the main body portion.

[0092] [Article 14] the inverter case has an end wall, and an outer surface of the end wall abuts against the end surface of the main body and the flange portion; The end wall has at least one through hole formed therein, At least one female thread portion is formed in the flange portion, Item 14. The electric compressor according to item 12 or 13, wherein a male thread portion of the second bolt is inserted into the through hole of the end wall and is screwed into the female thread portion of the flange portion.

[0093] [Article 15] The main body has a suction port formed adjacent to the end surface, The compression mechanism is configured to compress and discharge a refrigerant drawn into the main body through the suction port, the inverter case has an end wall, and an outer surface of the end wall abuts against the end surface of the main body and the flange portion; The electric compressor according to any one of clauses 12 to 14, wherein a switching element constituting the inverter is provided on a portion of the inner surface of the end wall adjacent to the end surface of the main body.

[0094] [Article 16] The electric compressor is mounted on a vehicle, The body portion extends horizontally, The inverter case extends in a vertical direction, a protrusion for fixing the inverter case to the vehicle is provided on an upper portion of the inverter case, 16. The electric compressor according to any one of claims 12 to 15, wherein the inverter case protrudes downward beyond the main body portion.

[0095] It goes without saying that the method of fixing the inverter case 7 and the flange portion 130 of the motor housing 20 using at least one second bolt 52, as described in the above-mentioned sixth embodiment and its modified examples, can be applied to the electric compressor 1 described in the above-mentioned first to fifth embodiments and their modified examples.

[0096] In the first to sixth embodiments and their modifications described above, a plurality of first bolts 51 are used to fasten the inverter case 7 to the main body 24 of the motor housing 20. In this regard, some of the plurality of first bolts 51 may be long bolts to collectively fasten the inverter cover 32, the inverter case 7, and the main body 24 of the motor housing 20. This makes it possible to omit some of the plurality of bolts 33.

[0097] In the sixth embodiment and its modified example described above, the multiple second bolts 52 are used to fasten the inverter case 7 to the flange portion 130 of the motor housing 20. In this regard, some of the multiple second bolts 52 may be long bolts to collectively fasten the inverter cover 32, the inverter case 7, and the flange portion 130 of the motor housing 20. This makes it possible to omit some of the multiple bolts 33.

[0098] In the first to sixth embodiments and their modifications described above, for the sake of convenience, the front-rear, left-right, and up-down directions are defined for the electric compressor 1. However, this is not intended to limit the orientation of the electric compressor 1. In other words, in the first to sixth embodiments and their modifications described above, the electric compressor 1 is a horizontally-mounted electric compressor in which the electric motor 4 and the compression mechanism 5 are arranged in series in the horizontal direction within the housing 2, but it may also be a vertically-mounted electric compressor in which the electric motor 4 and the compression mechanism 5 are arranged in series in the vertical direction within the housing 2.

[0099] In the first to sixth embodiments and their modifications described above, the electric compressor 1 is a scroll compressor, but the electric compressor 1 is not limited to a scroll compressor. For example, the electric compressor 1 may be a so-called swash plate compressor.

[0100] Although the embodiments and modifications of the present invention have been described above, the present invention is not limited to the above-described embodiments and modifications, and it goes without saying that further modifications are possible based on the technical concept of the present invention. [Explanation of symbols]

[0101] 1...electric compressor, 2...housing, 3...rotating shaft, 4...electric motor, 5...compression mechanism, 6...inverter, 7...inverter case, 8...fixed scroll, 8a...board, 9...orbiting scroll, 10...crank mechanism, 13...stator core unit, 14...rotor, 15...check valve, 16...oil separator, 20...motor housing, 21...rear housing, 24...main body, 24a...front end surface, 24b...rear end surface, 24c...female thread portion, 25...front tubular portion, 25a...front end surface, 26...rear tubular portion, 26b...rear end surface, 27...projection portion, 30...end wall, 30a...outer surface, 30a1...contact portion, 30a2...exposed portion, 30b...inner surface, 31...circumferential wall, 32...inverter cover, 33...bolt, 35...switching element, 36 ...control board, 38, 38'...through hole, 39...projection, 41...first protruding portion, 42...second protruding portion, 43, 44...female thread portion, 51...first bolt, 52...second bolt, 100, 100', 100"...connecting member, 101...main portion, 102, 102'...reinforcing portion, 111...first mounting portion, 111a...extension portion, 112...second mounting portion, 113, 11 3', 114, 115, 115'...through hole, 116, 116'...female thread, 121, 122, 123...bolt, 130...flange, 131...female thread, D1, D2...screw-in direction, H1...suction chamber, H2...compression chamber, H3...discharge chamber, H4...space, L1...refrigerant passage, L2...discharge hole, P1...suction port, P2...discharge port, R1, R2...rotation direction

Claims

1. An electric motor; a compression mechanism driven by the electric motor; an inverter that drives the electric motor; a motor housing that accommodates the electric motor; an inverter case that houses the inverter; at least one first bolt and at least one second bolt for abutting and fixing the inverter case to the motor housing; An electric compressor comprising: The motor housing has a cylindrical main body and a flange portion formed on one end surface of the main body, the end surface of the main body and the flange portion are in contact with the inverter case, the first bolt fixes the inverter case to the main body; The second bolt fixes the inverter case to the flange portion. Electric compressor.

2. The body portion is cylindrical, The electric compressor according to claim 1 , wherein the flange portion projects radially outward from the end surface of the main body.

3. the inverter case has an end wall, and an outer surface of the end wall abuts against the end surface of the main body and the flange portion; The end wall has at least one through hole formed therein, At least one female thread is formed in the flange portion, The electric compressor according to claim 1 , wherein the male thread portion of the second bolt is inserted into the through hole of the end wall and is screwed into the female thread portion of the flange portion.

4. The main body has a suction port formed adjacent to the end surface, The compression mechanism is configured to compress and discharge a refrigerant drawn into the main body through the suction port, the inverter case has an end wall, and an outer surface of the end wall abuts against the end surface of the main body and the flange portion; The electric compressor according to claim 1 , wherein a switching element constituting the inverter is provided on an inner surface of the end wall adjacent to the end surface of the main body.

5. The electric compressor is mounted on a vehicle, The body portion extends horizontally, The inverter case extends in a vertical direction, a protrusion for fixing the inverter case to the vehicle is provided on an upper portion of the inverter case, The electric compressor according to claim 1 , wherein the inverter case protrudes downward from the main body portion.

Images