Motor with built-in inverter

Abstract

To provide a motor with a built-in inverter that can be further reduced in size.SOLUTION: A motor with a built-in inverter comprises: a motor case that has a motor housing in a double cylindrical shape; a motor body that is arranged inside the motor housing; and an inverter that is arranged inside the motor case and at an axial end of the motor housing. The motor housing has a cylindrical outer member and a cylindrical inner member, and both members are fastened to each other at the axial end by bolt members that are arranged at an interval on the periphery. The motor housing has an opening that opens in the radial direction of the motor housing between any two bolt members of the bolt members seen from the axial direction of the motor housing. A PN bus bar of the inverter connected to a power supply is arranged in the opening.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a motor with a built-in inverter, and more particularly to a motor with a built-in inverter that can be further downsized and is particularly applicable to a drive motor for a vehicle. [Background technology]

[0002] Patent Document 1 discloses an electric motor control device that can achieve miniaturization and improved heat dissipation. This electric motor control device includes a drive circuit that drives an electric motor, a control circuit that controls the drive circuit, a housing in which an electric motor is mounted, a cover that also serves as a heat sink, and an input / output connector that electrically connects an external device to the drive circuit or the control circuit, and the drive circuit and the control circuit are housed in a storage space formed by engaging the cover on the side of the housing opposite to the electric motor. The cover has a connection surface that thermally connects a heat-generating electronic component included in the drive circuit, an external fin that protrudes from an outer surface that does not face the housing, and a recessed insertion portion that is provided inside the external fin and opens to face the storage space. The connection surface is parallel to the rotation axis of the electric motor, and is an inner surface of the insertion portion that is parallel to the rotation axis of the electric motor. The input / output connector is provided on the outer surface of the housing in a protruding manner parallel to the external fin and at a predetermined interval. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-158390 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in an electric motor control device such as that disclosed in Patent Document 1, the connection surfaces and input / output connectors are parallel to the rotational shaft of the electric motor, which causes the cylindrical housing to become longer in the direction of the rotational shaft of the electric motor, making it difficult to further reduce the size.

[0005] The present invention has been made in consideration of the problems associated with the conventional techniques, and has an object to provide a motor with a built-in inverter that can be made even smaller in size. [Means for solving the problem]

[0006] As a result of extensive research into achieving the above-mentioned object, the inventors discovered that the above-mentioned object can be achieved by having a motor housing with an opening that opens in the radial direction between any one of specified bolt members when viewed from the axial direction, and by arranging a PN bus bar of an inverter connected to a power source in the opening, thereby completing the present invention.

[0007] That is, the inverter-equipped motor of the present invention comprises a motor case having a motor housing having a double cylindrical shape, a motor body arranged in the motor housing, and an inverter arranged inside the motor case and at the axial end of the motor housing. The motor housing has a cylindrical outer member and a cylindrical inner member, and these two members are fastened together at their axial ends by bolt members that are circumferentially spaced apart. The motor housing has an opening that opens in the radial direction between any one of the bolt members when viewed in the axial direction. The PN bus bar of the inverter that is connected to the power supply is placed in the opening. Effect of the Invention

[0008] According to the present invention, the motor housing has an opening that opens in the radial direction between any one of the bolt members described above when viewed from the axial direction, and the PN bus bar of the inverter connected to the power source is arranged in the opening, thereby providing a motor with an integrated inverter that can be made even smaller. [Brief description of the drawings]

[0009] [Figure 1]1 is a perspective view showing a schematic diagram of an embodiment of an inverter-equipped motor according to the present invention; [Diagram 2] 2 is a plan view showing the inverter-equipped motor shown in FIG. 1. [Diagram 3] 3 is a cross-sectional view of the inverter-equipped motor shown in FIG. 2, taken along line III-III shown in FIG. 2. [Figure 4] FIG. 2 is an explanatory diagram illustrating a schematic diagram of a heat flow in an inverter. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The inverter-equipped motor of the present invention will be described in detail below with reference to the drawings. Note that the dimensional ratios of the drawings cited below are exaggerated for the convenience of explanation and may differ from the actual ratios.

[0011] Fig. 1 is a perspective view showing an embodiment of an inverter-equipped motor of the present invention, with a motor cover at the axial end of a motor housing in which an inverter is disposed removed. Fig. 2 is a plan view showing the inverter-equipped motor shown in Fig. 1 as seen from the axial end of the motor housing. Fig. 3 is a cross-sectional view of the inverter-equipped motor shown in Fig. 2, taken along line III-III in Fig. 2.

[0012] As shown in Figures 1 to 3, the inverter-integrated motor 1 of this embodiment includes a motor case 10 having a motor housing 11 having a double cylindrical shape, a motor main body 20 arranged in the motor housing 11, and an inverter 30 arranged inside the motor case 10 and at the axial end 11a of the motor housing 11.

[0013] Here, the motor body 20 has, for example, a rotor shaft, a rotor, and a stator. The rotor is integrally provided on the outer periphery of the rotor shaft, and the stator is annular and is disposed on the outer periphery of the rotor with a gap (not shown).

[0014] In addition, the motor case 10 (or the motor housing 11) rotatably supports a rotor shaft via a ball bearing (not shown).

[0015] Furthermore, in the illustrated example, the inverter 30 has a semiconductor power module 31, a PN bus bar 32, a PN connector 33 having positive and negative terminal blocks 33A, 33B, a smoothing capacitor 34, and a discharge resistor 35. The inverter controls the power from a power source such as a vehicle drive battery (not shown) to drive the motor body.

[0016] The motor housing 11 has a cylindrical outer member 11A and a cylindrical inner member 11B, and these two members 11A, 11B are fastened together at their axial ends 11a by bolt members 11C arranged circumferentially at intervals 11b. In the illustrated example, the bolt members 11C are arranged at six even positions.

[0017] The motor housing 11 has an opening 11c that opens in the radial direction between any one of the bolt members 11C when viewed from the axial direction (the axial end side in FIG. 2). Note that the opening 11c opens to the left in FIG. 1 and to the lower side in FIGS. 2 and 3.

[0018] Furthermore, a PN bus bar 32 of an inverter 30 that is connected to a power source such as a vehicle driving battery (not shown) is disposed in the opening 11c.

[0019] As shown in the illustrated example, the discharge resistor 35 of the inverter 30 is preferably disposed outside the opening 11c in the radial direction of the motor housing 11.

[0020] Furthermore, as in the illustrated example, it is preferable that the PN connector 33 of the inverter 30 is disposed at a position offset toward the center of the motor housing 11 in the axial direction relative to the discharge resistor 35.

[0021] Furthermore, as shown in the illustrated example, it is preferable that the motor housing 11 has a refrigerant flow path 11d between the cylindrical outer member 11A and the cylindrical inner member 11B, the refrigerant flow path 11d has a refrigerant flow path extension 11e at the axial end 11a, and a discharge resistor 35 or a PN bus bar 32 connected from the discharge resistor 35 is arranged at or near the refrigerant flow path extension 11e.

[0022] In the illustrated example, seal members 11D are disposed at both axial ends of the refrigerant flow path 11d, and the cylindrical outer member 11A and cylindrical inner member 11B forming the refrigerant flow path extension 11e are cooled by the refrigerant. However, the refrigerant does not flow through the refrigerant flow path extension 11e itself. Of course, if the insulation properties of the discharge resistor 35 and the PN bus bar 32 can be ensured, it is also possible to make the refrigerant flow through the refrigerant flow path extension 11e itself.

[0023] Next, advantages of this embodiment will be described. According to this embodiment, the motor housing 11 has an opening 11c that opens in the radial direction between any one of the bolt members 11C described above when viewed from the axial direction, and the PN bus bar 32 of the inverter 30 connected to the power source is disposed in the opening 11c, so that the PN connector provided on the PN bus bar of the inverter can be provided on the radial outside of the motor housing, and the axial length of the motor housing can be shortened, thereby achieving further miniaturization.

[0024] In particular, by providing the above-mentioned openings 11c between the bolt members 11C, there is no need to change the bolt pitch, so the axial length of the motor housing can be shortened without adversely affecting the sealing properties and rigidity of the motor housing, thereby achieving further miniaturization.

[0025] Furthermore, according to a preferred embodiment of the present invention, the discharge resistor 35 of the inverter 30 is disposed outside the radial opening 11c of the motor housing 11, so that the discharge resistor provided in the PN bus bar of the inverter can be provided on the radial outside of the motor housing, thereby further shortening the axial length of the motor housing and achieving further miniaturization.

[0026] Furthermore, according to a preferred embodiment of the present invention, the PN connector 33 of the inverter 30 is positioned offset toward the center of the motor housing 11 in the axial direction relative to the discharge resistor 35, thereby not only making it possible to further shorten the axial length of the motor housing, but also making it possible to further shorten the radial length of the motor housing, thereby achieving further miniaturization.

[0027] Furthermore, according to a preferred embodiment of the present invention, the motor housing 11 has a refrigerant flow path 11d between the cylindrical outer member 11A and the cylindrical inner member 11B, the refrigerant flow path 11d has a refrigerant flow path extension 11e at the axial end 11a, and the discharge resistor 35 and the PN bus bar 32 connected to the discharge resistor 35 are arranged at or near the refrigerant flow path extension 11e, thereby providing the advantage of being able to extract heat generated in the discharge resistor and the PN bus bar.

[0028] Here, the PN bus bar 32 connected from the discharge resistor 35 means a PN bus bar connected to the semiconductor power module 31 or the smoothing capacitor 34.

[0029] 4, the inverter 30 has, for example, a semiconductor power module 31, a PN bus bar 32, a PN connector 33 having positive and negative terminal blocks 33A, 33B, a smoothing capacitor 34, and a discharge resistor 35, and when heat is generated in the PN connector 33 or the discharge resistor 35, the heat can be removed via the PN bus bar or directly from the discharge resistor 35. In addition, 11e (11d) in the figure indicates a refrigerant flow path extension part (refrigerant flow path).

[0030] Although the present invention has been described above with reference to some embodiments, the present invention is not limited to these, and various modifications are possible within the scope of the gist of the present invention. [Explanation of symbols]

[0031] 1. Motor with built-in inverter 10 Motor case 11 Motor housing 11A Cylindrical outer member 11B Cylindrical inner member 11C Bolt parts 11D Sealing material 11a Axial end 11b spacing 11c opening 11d Coolant flow path 11e Refrigerant flow passage extension 20 Motor body 30 Inverter 31 Semiconductor power module 32PN busbar 33PN connector 33A,33B terminal block 34 Smoothing capacitor 35 Discharge resistor

Claims

1. The motor includes a motor case having a motor housing having a double cylindrical shape, a motor body disposed in the motor housing, and an inverter disposed in the motor case and at an axial end of the motor housing, the motor housing has a cylindrical outer member and a cylindrical inner member, and these members are fastened together at the axial end portions by bolt members arranged circumferentially at intervals, the motor housing has an opening portion that opens in a radial direction between any one of the bolt members when viewed from an axial direction of the motor housing, A PN bus bar of the inverter connected to a power source is disposed in the opening. A motor with a built-in inverter.

2. 2. The motor with a built-in inverter according to claim 1, wherein a discharge resistor of the inverter is disposed outside the opening in the radial direction of the motor housing.

3. 3. The motor with a built-in inverter according to claim 2, wherein a PN connector of the inverter is disposed at a position offset toward the center of the motor housing in the axial direction from the discharge resistor.

4. the motor housing has a refrigerant flow path between the cylindrical outer member and the cylindrical inner member, The coolant flow passage has a coolant flow passage extension portion at the axial end portion, and the discharge resistor or the PN bus bar connected from the discharge resistor is disposed at or near the coolant flow passage extension portion.

4. The inverter-equipped motor according to claim 2 or 3.

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