WO2019022116A1 - Motor - Google Patents

Abstract

In an embodiment of a motor according to the present invention, an inverter housing part is located outside a stator housing part in the radial direction. A housing is a single member, and includes a cylindrical circumferential wall part that surrounds a rotor and a stator outside the rotor and the stator in the radial direction. The circumferential wall part includes: a plurality of cooling flow paths arranged side by side in the axial direction; a connection flow path part that connects the cooling flow paths adjacent to one another in the axial direction; and a partitioning wall part that separates the stator housing part and the inverter housing part. The cooling flow paths extend in the circumferential direction, and at least a portion thereof is provided in the partitioning wall part. In the cooling flow paths adjacent to one another in the axial direction, a refrigerant flowing inside one cooling flow path flows from one side in the circumferential direction toward the other side in the circumferential direction and flows into the other cooling flow path through the connection flow path part, and the refrigerant flowing inside the other cooling flow path flows from the other side in the circumferential direction toward the one side in the circumferential direction.

Description

motor

The present invention relates to a motor.

A motor is known in which a rotor and a stator and an inverter device are housed in a housing and integrated. For example, Patent Document 1 describes a configuration in which a rotor, a stator, and an inverter device are disposed on a central axis in a housing.

JP, 2015-104257, A

In the motor as described above, it is required that the stator and the inverter device can be efficiently cooled. As a method of cooling the stator and the inverter device, it is conceivable to provide a cooling flow passage through which the refrigerant flows in the housing. However, simply providing the cooling flow path in the housing may not provide sufficient cooling efficiency of the stator and the inverter device.

An object of the present invention is to provide a motor having a structure capable of improving the cooling efficiency of a stator and an inverter unit by a cooling flow channel in view of the above-mentioned circumstances.

According to one aspect of the motor of the present invention, there is provided a rotor having a motor shaft disposed along a central axis extending in one direction, a stator opposed to the rotor via a gap in the radial direction, and the stator electrically An inverter unit to be connected, and a housing having a stator accommodating unit for accommodating the stator and an inverter accommodating unit for accommodating the inverter unit, the inverter accommodating unit being located radially outward of the stator accommodating unit The housing has a cylindrical peripheral wall portion surrounding the rotor and the stator on the radially outer side of the rotor and the stator, and is a single member, and the peripheral wall portions are plurally arranged in the axial direction. The cooling passage, the connection passage connecting the cooling passages adjacent in the axial direction, the stator housing portion, and the inverter housing portion. And the cooling flow path extends in the circumferential direction, and at least a portion of the cooling flow path is provided in the partition wall, and one of the cooling flow paths is provided in the axially adjacent cooling flow path. The refrigerant flowing in the flow path flows from one side in the circumferential direction to the other side in the circumferential direction, flows into the other cooling flow path through the connection flow path portion, and flows in the other cooling flow path The flowing refrigerant flows from the other side in the circumferential direction toward one side in the circumferential direction.

According to one aspect of the present invention, a motor having a structure capable of improving the cooling efficiency of the stator and the inverter unit by the cooling flow passage is provided.

FIG. 1 is a perspective view showing a motor of the present embodiment. FIG. 2 is a view showing the motor of the present embodiment, and is a cross-sectional view taken along the line II-II in FIG. FIG. 3 is a view showing the motor of the present embodiment, and is a cross-sectional view taken along the line III-III in FIG. FIG. 4 is a view of the motor of the present embodiment as viewed from the upper side. FIG. 5 is a perspective view showing a cooling unit of the present embodiment. FIG. 6 is a cross-sectional view showing a part of the motor of the present embodiment. FIG. 7 is a cross-sectional view showing a part of a motor according to a modification of the present embodiment.

The Z-axis direction shown in each drawing is the vertical direction Z with the positive side as the upper side and the negative side as the lower side. The Y-axis direction is a direction parallel to the central axis J extending in one direction shown in each drawing and a direction orthogonal to the vertical direction Z. In the following description, a direction parallel to the central axis J, that is, the Y-axis direction is referred to as “axial direction Y”. Further, the positive side in the axial direction Y is referred to as “axial one side”, and the negative side in the axial direction Y is referred to as “axial other side”. The X-axis direction shown in each drawing is a direction orthogonal to both the axial direction Y and the vertical direction Z. In the following description, the X-axis direction is referred to as "width direction X". Further, the positive side in the width direction X is referred to as "one side in the width direction", and the negative side in the width direction X is referred to as the other side in the width direction. In the present embodiment, the vertical direction Z corresponds to the first direction. The width direction X corresponds to a second direction.

Further, a radial direction centered on the central axis J is simply referred to as “radial direction”, and a circumferential direction centered on the central axis J is simply referred to as “circumferential direction θ”. In addition, in the circumferential direction θ, the side advancing clockwise as viewed from the other side in the axial direction to the one side in the axial direction, that is, the side advancing the arrow indicating the circumferential direction θ in the figure is referred to as “one side in the circumferential direction” The side advancing in the counterclockwise direction, that is, the side opposite to the advancing side of the arrow indicating the circumferential direction θ in the drawing is called “the other side in the circumferential direction”.

Note that the vertical direction and the upper and lower sides are simply names for describing the relative positional relationship of each part, and the actual positional relationship etc. is a positional relationship other than the positional relationship etc indicated by these names. May be

As shown in FIGS. 1 and 2, the motor 1 according to this embodiment includes a housing 10, a lid 11, a cover member 12, a sensor cover 13, and a motor shaft 21 disposed along a central axis J. It has a rotor 20, a stator 30, an inverter unit 50, a connector portion 18, and a rotation detection portion 70.

As shown in FIG. 2, the housing 10 accommodates the rotor 20, the stator 30, the rotation detection unit 70, and the inverter unit 50. The housing 10 is a single member. The housing 10 is made, for example, by sand casting. The housing 10 has a peripheral wall portion 10b, a bottom wall portion 10a, a bearing holding portion 10c, and a rectangular tube portion 10e.

The peripheral wall portion 10 b has a cylindrical shape that surrounds the rotor 20 and the stator 30 on the radially outer side of the rotor 20 and the stator 30. In the present embodiment, the peripheral wall portion 10 b is substantially cylindrical with the central axis J as a center. The peripheral wall portion 10 b is open to one side in the axial direction. The peripheral wall portion 10 b has a cooling portion 60 that cools the stator 30 and the inverter unit 50.

The bottom wall portion 10a is provided at the other end of the circumferential wall portion 10b in the axial direction. The bottom wall portion 10a closes the other side of the circumferential wall portion 10b in the axial direction. The bottom wall portion 10a has a sensor housing portion 10g penetrating the bottom wall portion 10a in the axial direction Y. The sensor storage portion 10 g has, for example, a circular shape centered on the central axis J when viewed along the axial direction Y. The bottom housing portion 10 a and the peripheral wall portion 10 b constitute a stator housing portion 14. That is, the housing 10 has a bottomed cylindrical stator housing portion 14 having a peripheral wall portion 10 b and a bottom wall portion 10 a.

The bearing holding portion 10c has a cylindrical shape that protrudes in the axial direction from the peripheral edge portion of the sensor accommodating portion 10g on the surface on the one side in the axial direction of the bottom wall portion 10a. The bearing holder 10 c holds a bearing that supports the motor shaft 21 on the other side in the axial direction with respect to the rotor core 22 described later.

As shown in FIGS. 1 to 4, the rectangular tube portion 10 e has a rectangular tube shape extending upward from the peripheral wall portion 10 b. The rectangular tube portion 10e opens upward. In the present embodiment, the rectangular tube portion 10 e has, for example, a square tube shape. As shown in FIG. 2, of the wall parts constituting the rectangular tube part 10 e, the wall part on the other side in the axial direction is connected to the upper end part of the bottom wall part 10 a. The square tube portion 10 e has a through hole 10 f penetrating in the axial direction Y a wall portion on one side in the axial direction among wall portions constituting the square tube portion 10 e. The lower end portion of the through hole 10 f is connected to the opening on one side in the axial direction of the peripheral wall portion 10 b. An inverter accommodating portion 15 is configured by the rectangular tube portion 10 e and the peripheral wall portion 10 b. That is, the housing 10 has an inverter accommodating portion 15.

The inverter accommodating portion 15 is located radially outside the stator accommodating portion 14. In the present embodiment, the inverter accommodating portion 15 is located above the stator accommodating portion 14 in the vertical direction Z orthogonal to the axial direction Y. The stator housing portion 14 and the inverter housing portion 15 are partitioned in the vertical direction Z by the partition wall portion 10 d. The partition wall portion 10d is an upper portion of the peripheral wall portion 10b. That is, the peripheral wall portion 10 b has a partition wall portion 10 d that divides the stator accommodation portion 14 and the inverter accommodation portion 15.

As shown in FIG. 3, the dimension in the vertical direction Z of the partition wall portion 10 d becomes larger as it goes away from the central axis J in the width direction X orthogonal to both the axial direction Y and the vertical direction Z. That is, the dimension in the vertical direction Z of the partition wall portion 10d is smallest at the central portion where the position in the width direction X is the same as the central axis J, and increases as moving away from the central portion on both sides in the width direction X.

The lid 11 shown in FIG. 2 has a plate shape whose plate surface is orthogonal to the vertical direction Z. The lid portion 11 is fixed to the upper end portion of the rectangular tube portion 10 e. The lid 11 closes the upper opening of the rectangular tube 10 e. In addition, illustration of the cover part 11 is abbreviate | omitted in FIG. As shown in FIGS. 1 and 2, the cover member 12 has a plate shape whose plate surface is orthogonal to the axial direction Y. The cover member 12 is fixed to a surface on one side in the axial direction of the peripheral wall portion 10b and the rectangular tube portion 10e. The cover member 12 closes the opening on one axial side of the peripheral wall portion 10b and the through hole 10f.

As shown in FIG. 2, the cover member 12 has an output shaft hole 12 a that penetrates the cover member 12 in the axial direction Y. The output shaft hole 12a has, for example, a circular shape passing through the central axis J. The cover member 12 has a bearing holding portion 12b projecting to the other axial side from the peripheral edge portion of the output shaft hole 12a in the surface on the other axial side of the cover member 12. The bearing holding portion 12 b holds a bearing that supports the motor shaft 21 on one side in the axial direction with respect to a rotor core 22 described later.

The sensor cover 13 is fixed to the other surface of the bottom wall portion 10 a in the axial direction. The sensor cover 13 covers and closes the opening on the other side in the axial direction of the sensor housing portion 10g. The sensor cover 13 covers the rotation detection unit 70 from the other side in the axial direction.

The rotor 20 has a motor shaft 21, a rotor core 22, a magnet 23, a first end plate 24 and a second end plate 25. The motor shaft 21 is rotatably supported by bearings at axially opposite portions. The end of the motor shaft 21 on the one side in the axial direction protrudes from the opening on the one side in the axial direction of the peripheral wall portion 10 b toward the one side in the axial direction. An end of the motor shaft 21 on one side in the axial direction passes through the output shaft hole 12 a and protrudes to one side in the axial direction with respect to the cover member 12. The other axial end of the motor shaft 21 is inserted into the sensor housing 10g.

The rotor core 22 is fixed to the outer peripheral surface of the motor shaft 21. The magnet 23 is inserted into a hole passing through the rotor core 22 provided in the rotor core 22 in the axial direction Y. The first end plate 24 and the second end plate 25 are in the form of a radially expanding annular plate. The first end plate 24 and the second end plate 25 sandwich the rotor core 22 in the axial direction Y while in contact with the rotor core 22. The first end plate 24 and the second end plate 25 press the magnet 23 inserted into the hole of the rotor core 22 from both sides in the axial direction.

The stator 30 faces the rotor 20 in the radial direction via a gap. The stator 30 has a stator core 31 and a plurality of coils 32 mounted on the stator core 31. The stator core 31 has an annular shape centered on the central axis J. The outer peripheral surface of the stator core 31 is fixed to the inner peripheral surface of the peripheral wall 10b. The stator core 31 faces the radially outer side of the rotor core 22 via a gap.

The inverter unit 50 controls the power supplied to the stator 30. The inverter unit 50 includes an inverter unit 51 and a capacitor unit 52. That is, the motor 1 includes an inverter unit 51 and a capacitor unit 52. The inverter unit 51 is accommodated in the inverter accommodation unit 15. The inverter unit 51 has a first circuit board 51a and a second circuit board 51b. The first circuit board 51 a and the second circuit board 51 b have a plate shape whose plate surface is orthogonal to the vertical direction Z. The second circuit board 51b is spaced apart above the first circuit board 51a. The first circuit board 51a and the second circuit board 51b are electrically connected. The coil wire 32 a is connected to the first circuit board 51 a via the connector terminal 53. Thus, the inverter unit 51 is electrically connected to the stator 30.

As shown in FIG. 2 and FIG. 4, the capacitor portion 52 is in the shape of a rectangular solid long in the width direction X. Capacitor portion 52 is accommodated in inverter accommodating portion 15. The capacitor unit 52 is disposed on the other side of the inverter unit 51 in the axial direction. That is, in the inverter accommodating portion 15, the inverter portion 51 and the capacitor portion 52 are arranged side by side in the axial direction Y. The capacitor unit 52 is electrically connected to the inverter unit 51. As shown in FIG. 2, the capacitor portion 52 is fixed to the upper surface of the partition wall portion 10 d. Condenser part 52 contacts partition wall part 10d.

As shown in FIG. 1, the connector portion 18 is provided on the other surface of the rectangular tube portion 10 e in the width direction. An external power supply (not shown) is connected to the connector portion 18. Power is supplied to the inverter unit 50 from an external power supply connected to the connector unit 18.

The rotation detection unit 70 detects the rotation of the rotor 20. In the present embodiment, the rotation detection unit 70 is, for example, a VR (Variable Reluctance) resolver. As shown in FIG. 2, the rotation detection unit 70 is accommodated in the sensor accommodation unit 10 g. That is, the rotation detection unit 70 is disposed on the bottom wall portion 10a. The rotation detection unit 70 includes a detection target unit 71 and a sensor unit 72.

The to-be-detected part 71 is annular shaped extended in the circumferential direction θ. The to-be-detected part 71 is fitted and fixed to the motor shaft 21. The to-be-detected part 71 is made of magnetic material. The sensor unit 72 has an annular shape surrounding the outside in the radial direction of the detection target 71. The sensor unit 72 is fitted to the sensor storage unit 10g. The sensor unit 72 is supported by the sensor cover 13 from the other side in the axial direction. That is, the sensor cover 13 supports the rotation detection unit 70 from the other side in the axial direction. The sensor unit 72 has a plurality of coils along the circumferential direction θ.

Although not shown, the motor 1 further includes a sensor wire that electrically connects the rotation detection unit 70 and the inverter unit 51. One end of the sensor wiring is connected to the detected portion 71. The sensor wiring is routed from the detected portion 71 to the inside of the inverter accommodating portion 15 through a through hole which penetrates the inside of the bottom wall portion 10a and the partition wall portion 10d in the radial direction. The other end of the sensor wiring is connected to, for example, the first circuit board 51a.

When the detected portion 71 rotates with the motor shaft 21, an induced voltage is generated in the coil of the sensor portion 72 according to the circumferential position of the detected portion 71. The sensor unit 72 detects the induced voltage to detect the rotation of the detection target unit 71. Thus, the rotation detection unit 70 detects the rotation of the motor shaft 21 and detects the rotation of the rotor 20. The rotation information of the rotor 20 detected by the rotation detection unit 70 is sent to the inverter unit 51 via the sensor wiring.

As shown in FIG. 5, the cooling unit 60 includes an upstream cooling flow channel 61 and a downstream cooling flow channel 62 as a plurality of cooling flow channels, and a connection flow channel section 63. That is, the peripheral wall portion 10 b includes the upstream side cooling flow path 61 and the downstream side cooling flow path 62 as the plurality of cooling flow paths, and the connection flow path portion 63. In the present embodiment, the upstream cooling passage 61 corresponds to a first cooling passage. The downstream side cooling flow passage 62 corresponds to a second cooling flow passage. In FIG. 5, the internal space of the cooling unit 60 is shown as a three-dimensional shape.

The plurality of cooling channels, that is, the upstream cooling channel 61 and the downstream cooling channel 62 in the present embodiment are aligned in the axial direction Y. The upstream cooling flow channel 61 and the downstream cooling flow channel 62 are two cooling flow channels adjacent to each other in the axial direction Y. In the present embodiment, the upstream cooling passage 61 is one of the two cooling passages adjacent in the axial direction Y, which is one cooling passage positioned on one side in the axial direction. The downstream side cooling flow passage 62 is the other cooling flow passage positioned on the other axial direction side of the two cooling flow passages adjacent in the axial direction Y.

The refrigerant flows through the upstream side cooling flow passage 61 and the downstream side cooling flow passage 62. The refrigerant is not particularly limited as long as it is a fluid that can cool the stator 30 and the inverter unit 51. The refrigerant may be water, a liquid other than water, or a gas.

The upstream cooling channel 61 extends in the circumferential direction θ. The upstream cooling flow passage 61 includes an upstream flow passage main portion 61 a, an inflow portion 61 b, and an inflow port 61 c. The upstream-side flow passage main portion 61a has an arc shape that is wide in the axial direction Y and extends in the circumferential direction θ. As shown in FIG. 3, the upstream side flow passage main portion 61 a extends from the portion on the other side in the width direction of the peripheral wall portion 10 b to the other side in the circumferential direction through the lower end portion of the peripheral wall portion 10 b Extend to The central angle φ of the upstream side channel body 61a is larger than 180 °. Thus, the upstream cooling flow passage 61 has an arc shape with a central angle larger than 180 °.

The inflow part 61b is connected with the upstream flow-path main-body part 61a. In more detail, the inflow part 61b is connected with the edge part of the circumferential direction one side of the upstream flow-path main-body part 61a. The inflow portion 61 b extends upward from an end portion on one side in the circumferential direction of the upstream side flow path main portion 61 a. As shown in FIG. 5, the dimension in the axial direction Y of the inflow portion 61 b is the same as the dimension in the axial direction Y of the upstream side flow passage main portion 61 a. The dimension in the width direction X of the inflow portion 61 b is larger than the dimension in the radial direction of the upstream-side flow passage main portion 61 a. As shown in FIG. 3, the upper end portion of the inflow portion 61 b is located lower than the upper end portion of the upstream flow passage main portion 61 a. The inflow portion 61 b is an end portion on one circumferential side of the upstream cooling flow passage 61.

The inlet 61 c is provided at the inlet 61 b. That is, the inflow port 61 c is located at one end of the upstream cooling flow path 61 in the circumferential direction. As shown in FIG. 5, the inflow port 61c protrudes from the central portion in the axial direction Y and the vertical direction Z in the inflow portion 61b to the other side in the width direction. The refrigerant flows into the inflow port 61c. The cross-sectional shape orthogonal to the width direction X of the inflow port 61c is, for example, a circular shape. As shown in FIG. 3, the inflow pipe 16 is connected to the inflow port 61 c. The inflow pipe 16 is inserted into a hole provided in the housing 10. The inflow pipe 16 protrudes from the housing 10 to the other side in the width direction.

At least a part of the upstream side cooling flow passage 61 is provided in the partition wall portion 10d. Therefore, the stator housing portion 14 and the inverter housing portion 15 partitioned by the partition wall portion 10d can be cooled by the refrigerant flowing through the upstream cooling flow passage 61, and the stator 30 and the inverter housing housed in the stator housing portion 14 The inverter unit 51 accommodated in the unit 15 can be cooled.

In the present embodiment, the upper portion and the inflow portion 61b of the upstream side flow path main portion 61a are provided in the partition wall portion 10d. As viewed along the vertical direction Z, the portion of the upstream cooling flow passage 61 provided on the partition wall portion 10 d has a portion overlapping the inverter portion 51. Accordingly, the inverter unit 51 can be more easily cooled by the upstream cooling flow passage 61. In the present embodiment, among the portions of the upstream cooling flow passage 61 provided in the partition wall portion 10 d, the upper portion of the upstream flow passage main portion 61 a overlaps the inverter portion 51 as viewed in the vertical direction Z.

In the present embodiment, a portion provided on the partition wall portion 10 d of the upstream side cooling flow passage 61 is a single layer flow passage between the stator accommodation portion 14 and the inverter portion 51 in the radial direction. Therefore, the configuration of the upstream side cooling flow passage 61 can be simplified as compared to the case where the flow passages of a plurality of layers are provided side by side in the radial direction. Further, the dimension in the radial direction of the partition wall portion 10d can be easily reduced, and the motor 1 can be easily miniaturized.

In the present specification, "a channel is a channel in a single layer in a part" includes that only one continuous channel is provided in a part. For example, even if the same flow path is continuous as a whole, in the case where two portions that are discontinuous in a certain portion are provided, a plurality of layers of flow paths are provided in a certain portion. In the present embodiment, the portion of the upstream cooling flow passage 61 provided between the stator accommodation portion 14 and the inverter portion 51 in the radial direction is only one continuous portion.

As shown in FIG. 4, the maximum dimension in the width direction X of the upstream cooling flow passage 61 is larger than the dimension in the width direction X of the second circuit board 51 b and the dimension in the width direction X of the capacitor portion 52. Moreover, although illustration is abbreviate | omitted, the largest dimension of the width direction X of the upstream cooling flow path 61 is larger than the dimension of the width direction X of the 1st circuit board 51a. Therefore, it is easier to cool the inverter unit 51 by the upstream cooling flow passage 61. The maximum dimension in the width direction X of the upstream cooling flow passage 61 refers to the portion of the upstream cooling flow passage 61 located most on the one side in the width direction and the region located on the upstream cooling flow path 61 on the other side in the width direction And the distance in the width direction X between. In the present embodiment, the maximum dimension in the width direction X of the upstream cooling flow passage 61 corresponds to the outer diameter of the arc-shaped upstream cooling flow passage 61.

As shown in FIG. 5, the downstream cooling channel 62 is disposed on the other axial side of the upstream cooling channel 61. The shape of the downstream side cooling flow passage 62 is the same as the shape of the upstream side cooling flow passage 61. The downstream side cooling flow passage 62 has a downstream side flow passage main portion 62a, an outflow portion 62b, and an outflow port 62c. The shape of the downstream side flow passage main portion 62a is the same as the shape of the upstream side flow passage main portion 61a.

The outflow portion 62b is connected to the downstream flow path main body 62a. In more detail, the outflow part 62b is connected with the edge part of the circumferential direction one side of the downstream flow-path main-body part 62a. The outflow portion 62 b extends upward from an end on one circumferential side of the downstream side flow path main portion 62 a. The dimension in the axial direction Y of the outflow portion 62b is the same as the dimension in the axial direction Y of the downstream side flow passage main portion 62a. The dimension in the width direction X of the outflow portion 62b is larger than the dimension in the radial direction of the downstream side flow passage main portion 62a. The upper end portion of the outflow portion 62b is located below the upper end portion of the downstream flow passage main portion 62a. The shape of the outflow portion 62b is the same as the shape of the inflow portion 61b. The outflow portion 62 b is an end on one circumferential side of the downstream side cooling flow passage 62.

The outlet 62c is provided at the outlet 62b. That is, the outlet 62 c is located at one end of the downstream cooling channel 62 in the circumferential direction. The outlet 62c protrudes from the central portion in the axial direction Y and the vertical direction Z in the outlet portion 62b to the other side in the width direction. The refrigerant flows out from the outlet 62c. The cross-sectional shape orthogonal to the width direction X of the outflow port 62c is, for example, a circular shape. The shape of the outlet 62c is similar to the shape of the inlet 61c. The inlet 61 c and the outlet 62 c are disposed at the same position in the vertical direction Z. The inlet 61 c and the outlet 62 c are spaced apart in the axial direction Y.

The outflow pipe 17 shown in FIG. 1 is connected to the outflow port 62c. The outflow pipe 17 is inserted into a hole provided in the housing 10. The outflow pipe 17 projects from the housing 10 to the other side in the width direction. The inflow pipe 16 and the outflow pipe 17 are disposed at the same position in the vertical direction Z. The inflow pipe 16 and the outflow pipe 17 are spaced apart in the axial direction Y.

As shown in FIG. 2, at least a part of the downstream side cooling flow passage 62 is provided in the partition wall portion 10 d. Therefore, the stator housing portion 14 and the inverter housing portion 15 partitioned by the partition wall portion 10d can be cooled by the refrigerant flowing through the downstream side cooling flow passage 62, and the stator 30 and the inverter housing housed in the stator housing portion 14 The inverter unit 51 accommodated in the unit 15 can be cooled.

In the present embodiment, the upper side portion of the downstream side flow path main portion 62a and the outflow portion 62b are provided in the partition wall portion 10d. As viewed along the vertical direction Z, the portion provided on the partition wall portion 10d of the downstream side cooling flow passage 62 has a portion overlapping with the inverter portion 51 and a portion overlapping with the capacitor portion 52. Therefore, the stator 30, the inverter unit 51, and the capacitor unit 52 can be cooled by the refrigerant flowing in the downstream side cooling flow passage 62. Therefore, three parts can be simultaneously cooled by one downstream cooling channel 62, and cooling can be performed efficiently while reducing the number of cooling channels. Therefore, according to this embodiment, the motor 1 having a structure capable of improving the cooling efficiency of the stator 30, the inverter unit 51, and the capacitor unit 52 by the cooling flow passage can be obtained.

Further, as described above, in the present embodiment, the capacitor portion 52 contacts the partition wall portion 10d. Therefore, the heat of the condenser portion 52 is easily released to the refrigerant in the downstream side cooling flow path 62 along the partition wall portion 10d. Therefore, the condenser portion 52 can be more easily cooled by the downstream side cooling flow path 62.

In the present embodiment, the portion provided in the partition wall portion 10d of the downstream side cooling flow passage 62 is a single layer flow passage between the stator accommodation portion 14 and the inverter portion 51 in the radial direction, and the stator accommodation portion A single layer flow path is provided between the radial direction of the capacitor 14 and the capacitor portion 52. That is, the portion of the downstream side cooling flow passage 62 provided between the stator accommodation portion 14 and the inverter portion 51 in the radial direction is only one continuous portion. Further, the portion of the downstream side cooling flow passage 62 provided between the stator accommodation portion 14 and the capacitor portion 52 in the radial direction is only one continuous portion. Therefore, the configuration of the downstream side cooling flow passage 62 can be simplified as compared with the case where the flow passages of a plurality of layers are provided side by side in the radial direction. Further, the dimension in the radial direction of the partition wall portion 10d can be easily reduced, and the motor 1 can be easily miniaturized.

As shown in FIG. 4, the maximum dimension in the width direction X of the downstream side cooling flow passage 62 is larger than the dimension in the width direction X of the second circuit board 51 b and the dimension in the width direction X of the capacitor portion 52. Although not shown, the maximum dimension in the width direction X of the downstream side cooling flow passage 62 is larger than the dimension in the width direction X of the first circuit board 51a. Therefore, it is easier to cool the inverter unit 51 and the capacitor unit 52 by the downstream side cooling flow passage 62. The largest dimension in the width direction X of the downstream side cooling flow passage 62 refers to the portion located on the one side in the width direction in the downstream cooling flow passage 62 and the portion located on the other side in the width direction on the downstream cooling passage 62 And the distance in the width direction X between. In the present embodiment, the maximum dimension in the width direction X of the downstream cooling flow passage 62 corresponds to the outer diameter of the arc-shaped downstream cooling flow passage 62. The maximum dimension in the width direction X of the downstream cooling channel 62 is, for example, the same as the maximum dimension in the width direction X of the upstream cooling channel 61.

The dimension of the upstream cooling passage 61 in the axial direction Y and the dimension of the downstream cooling passage 62 in the axial direction Y are the same. That is, the dimensions in the axial direction Y of the plurality of cooling channels are the same as one another. The radial dimension of the upstream cooling channel 61 and the radial dimension of the downstream cooling channel 62 are the same. That is, the dimensions in the radial direction of the plurality of cooling channels are the same.

In addition, comparison of the dimension of the axial direction Y of each cooling flow path and the dimension of radial direction includes the comparison of each flow-path main-body part, for example. That is, the dimension in the axial direction Y of the upstream side flow passage main portion 61a and the dimension in the axial direction Y of the downstream side flow passage main portion 62a are the same. The radial dimension of the upstream side flow passage main portion 61a and the radial dimension of the downstream side flow passage main portion 62a are the same.

As shown in FIG. 6, the partition wall portion 10d is positioned between the cooling flow passage and the inverter portion 51 in the portion 10j located between the cooling flow passage and the radial direction of the inverter accommodating portion 15 The portion 10i has a smaller radial dimension than the portion 10h located between the cooling flow passage and the condenser portion 52 in the radial direction. That is, the radial dimension L1 of the portion 10i is smaller than the radial dimension L3 of the portion 10h. Thus, the cooling flow path can be brought close to the inverter unit 51, and the inverter unit 51 can be cooled more easily.

In the present embodiment, the portion 10i is a portion of the partition wall portion 10d located between the upstream side cooling flow passage 61 and the inverter portion 51 in the radial direction, and the downstream side cooling flow passage 62 and the inverter of the partition wall portion 10d. And a portion positioned between the portion 51 and the radial direction. The portion 10 h includes a portion of the partition wall portion 10 d located between the downstream side cooling flow passage 62 and the condenser portion 52 in the radial direction.

The portion 10 j of the partition wall portion 10 d located between the cooling flow path and the inverter housing portion 15 in the radial direction is located between the cooling flow path and the stator housing portion 14 in the partition wall portion 10 d. The radial dimension is smaller than that of the portion 10k. That is, the radial dimension L1 of the portion 10i and the radial dimension L3 of the portion 10h are smaller than the radial dimension L2 of the portion 10k. As a result, the cooling passage can be made closer to the inverter accommodating portion 15 than the stator accommodating portion 14, and the inverter accommodating portion 15 can be more easily cooled. Further, since the dimension L2 can be relatively easily increased, the dimension in the radial direction of the portion of the circumferential wall portion 10b in contact with the stator core 31 can be easily increased. Thereby, the intensity | strength holding the stator core 31 in the surrounding wall part 10b can be comparatively enlarged. As described above, the dimension L1, the dimension L2, and the dimension L3 satisfy the relationship of L1 <L3 <L2.

Note that the above-described magnitude relationship between the dimension L1, the dimension L2, and the dimension L3 may be established at least between the minimum values of the respective dimensions. For example, in the present embodiment, although the dimension L1 and the dimension L2 differ depending on the position in the circumferential direction θ, when the minimum value of the dimension L1 and the minimum value of the dimension L2 are compared with the dimension L3, L1 <L3 <L2 described above It suffices to satisfy the relationship. In the present embodiment, the magnitude relationship among the dimensions L1, L2, and L3 satisfies the relationship of L1 <L3 <L2 at the central portion in the width direction X of the partition wall 10d.

As shown in FIG. 5, the connection flow path portion 63 connects the cooling flow paths adjacent to each other in the axial direction Y. That is, in the present embodiment, the connection flow channel portion 63 connects the upstream cooling flow channel 61 and the downstream cooling flow channel 62. More specifically, the connection flow path portion 63 connects the other end of the upstream cooling flow path 61 in the circumferential direction and the other end of the downstream cooling flow path 62 in the circumferential direction.

Accordingly, the refrigerant in the upstream cooling flow passage 61 flows into the downstream cooling flow passage 62 via the connection flow passage portion 63. More specifically, the refrigerant flowing from the inflow pipe 16 into the upstream cooling flow passage 61 via the inflow port 61 c is cooled downstream from the inflow portion 61 b via the upstream flow passage main portion 61 a and the connection flow passage portion 63. It flows into the flow path 62. That is, the refrigerant flowing in the upstream side cooling flow passage 61 flows from one side in the circumferential direction to the other side in the circumferential direction, and flows into the downstream side cooling flow passage 62 via the connection passage portion 63. The refrigerant flowing in the connection flow path portion 63 flows from the other side in the axial direction toward the one side in the axial direction.

The refrigerant flowing in the downstream side cooling flow passage 62 flows from the other side in the circumferential direction toward the one side in the circumferential direction via the downstream side flow passage main portion 62a, the outflow portion 62b and the outflow port 62c in this order. As described above, in the cooling channels adjacent to each other in the axial direction Y, the directions of the circumferential direction θ in which the refrigerant flows are opposite to each other. The refrigerant in the downstream side cooling flow passage 62 flows out of the outlet 62 c to the outside of the housing 10 through the outlet pipe 17.

According to the present embodiment, since a plurality of cooling channels are provided, the amount of refrigerant flowing in the cooling channels can be increased. Thereby, the stator 30 and the inverter unit 51 can be more easily cooled. Further, since the plurality of cooling flow paths are connected by the connection flow path portion 63, the refrigerant can flow in the plurality of cooling flow paths by providing the inlet 61c and the outlet 62c one by one, which is simple is there. Further, in order to connect the cooling channels extending in the circumferential direction θ in the axial direction Y and connect them, for example, the cooling channels extending in the axial direction Y are connected in the circumferential direction θ and connected, respectively. The flow path portion 63 can be easily manufactured.

Further, by arranging the plurality of cooling channels in the axial direction Y, the dimensions of the respective cooling channels in the axial direction Y can be reduced to reduce the cross-sectional area of each cooling channel, and the plurality of cooling flows can be obtained. As a whole, the dimension in the axial direction Y can be secured. Thus, the flow rates of the refrigerant flowing in the respective cooling flow paths can be relatively increased, and the cooling efficiency of the stator 30 and the inverter unit 51 by the refrigerant can be improved. Further, since the dimensions in the axial direction Y can be secured for the plurality of cooling channels as a whole, the relatively wide range of the stator housing portion 14 and the inverter housing portion 15 can be cooled, and the stator 30 and the inverter portion 51 can be cooled more.

Moreover, since the dimension of the axial direction Y of each cooling flow path can be made comparatively small, it can suppress that the flow of a refrigerant | coolant stops in each cooling flow path. Accordingly, it is possible to suppress the change in the flow velocity of the refrigerant in each cooling channel depending on the position in the circumferential direction θ, and it is easy to make the degree of cooling by the refrigerant uniform in the circumferential direction θ. Therefore, the cooling efficiency of stator 30 and inverter unit 51 can be further improved.

As described above, according to the present embodiment, the motor 1 having a structure capable of improving the cooling efficiency of the stator 30 and the inverter unit 51 by the cooling flow passage can be obtained.

Further, according to the present embodiment, the connection flow path portion 63 connects the end portion on the other side in the circumferential direction of the upstream side cooling flow path 61 and the end portion on the one side in the circumferential direction of the downstream side cooling flow path 62 . Therefore, in the upstream side cooling flow passage 61 and the downstream side cooling flow passage 62, generation of a portion in which the refrigerant stagnates can be suppressed. Accordingly, stagnation of the flow of the refrigerant in each cooling channel can be further suppressed, and the cooling efficiency can be further improved.

Further, according to the present embodiment, two cooling flow paths, ie, the upstream cooling flow path 61 and the downstream cooling flow path 62, are provided, and the inflow port 61c is provided at one circumferential end of each cooling flow path. And the outlet 62 c are located respectively. That is, in each of the upstream cooling flow channel 61 and the downstream cooling flow channel 62, the inflow port 61c or the outflow port 62c is provided at the same end of the circumferential direction θ. Therefore, the inflow pipe 16 and the outflow pipe 17 can be provided on the same side of the housing 10, and it is easy to connect a pump or the like for circulating the refrigerant to the motor 1. In addition, by setting the number of cooling channels to two, it is possible to easily make a plurality of cooling channels, as compared to the case where the number of cooling channels is relatively large.

Further, according to the present embodiment, the portion provided on the partition wall portion 10d of the upstream cooling flow passage 61 has a portion overlapping the inverter portion 51 when viewed along the vertical direction Z, and is also downstream A portion of the cooling flow passage 62 provided in the partition wall portion 10 d has a portion overlapping the capacitor portion 52. Then, the refrigerant that has flowed in from the inflow port 61 c flows in the upstream side cooling flow path 61 earlier than the downstream side cooling flow path 62. Therefore, the inverter unit 51 can be cooled by the relatively low temperature refrigerant introduced from the inflow port 61c. This makes it easier to cool the inverter unit 51. The heat generation of the inverter unit 51 is particularly likely to be large, and thus the motor 1 can be cooled more preferably by cooling the inverter unit 51 easily.

Further, according to the present embodiment, each cooling channel is in the shape of a circular arc having a central angle φ larger than 180 °. Therefore, it is easy to surround the stator 30 by the cooling flow path, and the stator 30 can be cooled more.

Further, according to the present embodiment, the dimensions in the axial direction Y of the plurality of cooling channels are the same as one another. Therefore, it is easy to produce a plurality of cooling channels. In addition, it is easy to make the cross-sectional area of each cooling channel the same. This makes it easy to equalize the flow velocity of the refrigerant in each cooling channel, and to easily make the degree of cooling by each cooling channel uniform. In the present embodiment, the dimension in the axial direction Y of the upstream cooling flow passage 61 and the dimension in the axial direction Y of the downstream cooling flow passage 62 are the same as each other. Therefore, the upstream cooling passage 61 and the downstream cooling passage 62 can be easily manufactured, and the degree of cooling by the upstream cooling passage 61 and the degree of cooling by the downstream cooling passage 62 can be easily made the same.

Further, according to the present embodiment, the radial dimensions of the plurality of cooling channels are the same. Therefore, it is easy to produce a plurality of cooling channels. In addition, it is easy to make the cross-sectional area of each cooling channel the same. This makes it easier to make the flow velocity of the refrigerant the same in each cooling channel, and to make the degree of cooling by each cooling channel more uniform.

As shown in FIG. 5, the connection passage portion 63 extends in the axial direction Y. The end on one axial side of the connection flow channel portion 63 is at the same position in the axial direction Y as the end on one axial side of the upstream cooling flow passage 61. The other axial end of the connection flow passage portion 63 is at the same position in the axial direction Y as the axial other end of the downstream cooling flow passage 62.

As shown in FIG. 3, the radial dimension of the connection flow channel portion 63 is the radial dimension of the cooling flow channel, that is, the radial dimension of the upstream cooling flow channel 61 and the radial dimension of the downstream cooling flow channel 62 Larger than the size of. Therefore, it is easy to make the flow passage cross-sectional area in the connection flow passage portion 63 larger than the flow passage cross-sectional area of the upstream cooling flow passage 61 and the flow passage cross-sectional area of the downstream cooling flow passage 62. As a result, when the refrigerant flows from the connection flow passage portion 63 to the downstream side cooling flow passage 62, the flow passage cross-sectional area is reduced, whereby the flow velocity of the refrigerant can be improved. Accordingly, the flow velocity of the refrigerant can be easily increased in the downstream side cooling flow passage 62, and the cooling efficiency by the downstream side cooling flow passage 62 can be further improved. Further, the pressure loss of the refrigerant flowing from the upstream cooling flow passage 61 into the connection flow passage portion 63 can be reduced.

As shown in FIG. 5, the radial dimension of the connection flow channel portion 63 is the dimension of the cooling flow channel in the axial direction Y, that is, the dimension of the upstream cooling flow channel 61 in the axial direction Y and the downstream cooling flow channel 62 Smaller than the dimension in the axial direction Y of Thereby, it can suppress that the dimension of the radial direction of the connection flow-path part 63 becomes large too much. Therefore, stagnation of the flow of the refrigerant in the connection flow path portion 63 can be suppressed.

The dimension in the radial direction of the connection passage portion 63 differs depending on the position in the circumferential direction θ. The dimension of the connection flow path portion 63 in the radial direction is the largest at the central portion of the connection flow path portion 63 in the circumferential direction θ, and becomes smaller as the distance from the central portion to both sides in the circumferential direction θ. The central portion in the circumferential direction θ of the connection flow passage portion 63 and the end portion on the other circumferential direction side of the connection flow passage portion 63 are rounded.

As shown in FIG. 3, the connection flow channel portion 63 is provided in the partition wall portion 10 d. Therefore, the stator 30 and the inverter unit 51 can be cooled also by the refrigerant flowing through the connection flow passage portion 63. Therefore, the stator 30 and the inverter unit 51 can be cooled more. When the flow passage cross-sectional area of the connection flow passage 63 is larger than the flow passage cross-sectional area of the upstream cooling flow passage 61 and the flow passage cross-sectional area of the downstream cooling flow passage 62 as in the present embodiment, the connection flow The amount of refrigerant flowing through the passage portion 63 can be increased, and the stator 30 and the inverter portion 51 can be more easily cooled.

In the present embodiment, the connection flow path portion 63 is provided in a portion of the partition wall portion 10d near the other side in the width direction. Here, as described above, the dimension in the vertical direction Z of the partition wall portion 10d becomes larger as the distance from the central axis J in the width direction X increases. Therefore, the part of the partition wall 10d closer to the other side in the width direction has a larger dimension in the vertical direction Z than the central portion in the width direction X of the partition wall 10d. Therefore, even if the dimension in the radial direction of the connection flow passage 63 is larger than the dimension in the radial direction of the cooling flow passage as in the present embodiment, the connection flow passage 63 can be easily provided in the partition wall 10d.

In the present embodiment, the cooling unit 60 is formed by a portion of the sand mold having the shape of the cooling unit 60 when the housing 10 is manufactured by sand casting. As shown in FIGS. 1 and 2, the housing 10 has a plurality of discharge holes 19 for discharging a sand mold for forming the cooling unit 60. After the housing 10 is manufactured by sand casting, the sand mold for forming the cooling unit 60 is discharged from the discharge hole 19. The discharge hole 19 is connected to the cooling unit 60. The plug 80 is pressed into the discharge hole 19. The discharge hole 19 is closed by the plug 80, and the refrigerant in the cooling unit 60 can be prevented from leaking to the outside of the housing 10.

(Modification)
As shown in FIG. 7, in the housing 110 of the present modification, the cooling flow passage and the capacitor portion 52 are provided in the portion 110 j of the partition wall portion 110 d located between the cooling flow passage and the radial direction of the inverter accommodating portion 15. The portion 110 h located between the radial directions of the radial direction has a smaller dimension in the radial direction than the portion 110 i located between the cooling flow path and the radial direction of the inverter portion 51. That is, the radial dimension L6 of the portion 110h is smaller than the radial dimension L4 of the portion 110i. As a result, the cooling flow path can be easily brought close to the condenser portion 52, and the condenser portion 52 can be cooled more easily.

In the present modification, the portion 110i is a portion of the partition wall portion 110d located in the radial direction between the upstream side cooling flow passage 161 and the inverter portion 51, and the downstream side cooling flow passage 162 and the inverter of the partition wall portion 110d. And a portion positioned between the portion 51 and the radial direction. The portion 110 h includes a portion of the partition wall portion 110 d located between the downstream side cooling flow passage 162 and the condenser portion 52 in the radial direction. In the present modification, the upper surface of the partition wall portion 110d in contact with the capacitor portion 52 is located lower than the upper surface of the partition wall portion 110d on which the inverter portion 51 is installed.

The portion 110k of the partition wall portion 110d located between the cooling flow passage and the stator accommodation portion 14 in the radial direction is located between the cooling flow passage and the inverter accommodation portion 15 in the partition wall portion 110d. The radial dimension is smaller than that of the portion 110 j. That is, the radial dimension L5 of the portion 110k is smaller than the radial dimension L4 of the portion 110i and the radial dimension L6 of the portion 110h. As a result, the cooling flow path can be made closer to the stator accommodation portion 14 than the inverter accommodation portion 15, and the stator accommodation portion 14 can be more easily cooled. Thus, the dimension L4, the dimension L5, and the dimension L6 satisfy the relationship of L5 <L6 <L4.

The present invention is not limited to the above-described embodiment, and other configurations can be adopted. The cooling channel may have an arc shape with a central angle φ of 180 ° or less. If a plurality of cooling channels are provided, three or more may be provided. The radial dimensions of the plurality of cooling channels may be different from one another. The dimensions in the axial direction Y of the plurality of cooling channels may be different from one another. The shapes of the plurality of cooling channels may be different from one another. The portion provided in the partition wall portion in the cooling flow path may not overlap with the inverter portion or may not overlap with the capacitor portion as viewed along the vertical direction Z.

The connection flow path portion is not particularly limited as long as the cooling flow paths adjacent in the axial direction Y are connected. The radial dimension of the connection channel portion may be the same as the radial dimension of the cooling channel, or may be smaller than the radial dimension of the cooling channel. The connection flow path portion may connect intermediate portions in the circumferential direction θ in the cooling flow path. The connection channel portion may be provided in a portion other than the partition wall portion in the peripheral wall portion. A plurality of connection channel parts may be provided.

The application of the motor of the embodiment described above is not particularly limited. The motor of the embodiment described above is mounted on, for example, a vehicle. Moreover, each structure mentioned above can be combined suitably in the range which does not contradiction mutually.

This application claims priority based on Japanese Patent Application No. 201-147112, which is a Japanese patent application filed on July 28, 2017, and incorporates the entire contents described in the Japanese patent application.

DESCRIPTION OF SYMBOLS 1 ... Motor, 10, 110 ... Housing, 10b ... Peripheral wall part, 10d, 110d ... Partition wall part 14 ... Stator accommodating part, 15 ... Inverter accommodating part, 20 ... Rotor, 21 ... Motor shaft, 30 ... Stator, 51 ... Inverter unit, 52: capacitor unit, 61, 161: upstream cooling flow passage (first cooling flow passage), 61c: inlet, 62, 162: downstream cooling flow passage (second cooling flow passage), 62c: flow Outlet, 63: connection flow path portion, J: central axis, X: width direction (second direction), Y: axial direction, Z: vertical direction (first direction), θ: circumferential direction, φ: central angle

Claims (13)

A rotor having a motor shaft disposed along a central axis extending in one direction;
A stator that faces the rotor in the radial direction via a gap;
An inverter unit electrically connected to the stator;
A housing having a stator housing portion for housing the stator and an inverter housing portion for housing the inverter portion;
Equipped with
The inverter accommodating portion is located radially outward of the stator accommodating portion.
The housing has a cylindrical peripheral wall portion surrounding the rotor and the stator on the radially outer side of the rotor and the stator, and is a single member.
The peripheral wall portion is
A plurality of cooling channels aligned in the axial direction;
A connecting flow passage portion connecting the cooling flow passages adjacent in the axial direction;
A partition wall which partitions the stator housing portion and the inverter housing portion;
Have
The cooling channel extends in the circumferential direction, and at least a portion of the cooling channel is provided in the partition wall portion.
In the axially adjacent cooling channels,
The refrigerant flowing in one of the cooling flow paths flows from one circumferential side to the other circumferential side, and flows into the other cooling flow path through the connection flow path portion.
The motor, in which the refrigerant flowing in the other cooling flow channel flows from the other side in the circumferential direction toward one side in the circumferential direction. 2. The motor according to claim 1, wherein the connection passage section connects an end on the other side in the circumferential direction of the one cooling passage and an end on the one side in the circumferential direction of the other cooling passage. Two cooling channels are provided,
Of the two cooling channels, the first cooling channel, which is the cooling channel positioned on one side in the axial direction, has an inlet through which the refrigerant flows.
Of the two cooling channels, the second cooling channel, which is the cooling channel positioned on the other side in the axial direction, has an outlet through which the refrigerant flows out,
The inlet is located at one end of the first cooling channel in the circumferential direction,
The motor according to claim 1, wherein the outlet is located at one circumferential end of the second cooling channel. It further comprises a capacitor unit electrically connected to the inverter unit,
The capacitor portion is accommodated in the inverter accommodating portion and disposed on the other side in the axial direction of the inverter portion.
The inverter accommodating portion is located on one side of the stator accommodating portion in a first direction orthogonal to the axial direction.
As viewed along the first direction, a portion of the first cooling flow path provided on the partition wall portion has a portion overlapping the inverter portion, and the partition of the second cooling flow path The motor according to claim 3, wherein the portion provided on the wall has a portion overlapping with the capacitor portion. In a portion of the partition wall portion located in the radial direction between the cooling flow path and the inverter accommodating portion, a portion located between the cooling flow path and the inverter portion in the radial direction is the cooling flow The motor according to claim 4, wherein a dimension in a radial direction is smaller than a portion positioned between the passage and the capacitor portion in the radial direction. The motor according to any one of claims 1 to 5, wherein the cooling channel is an arc having a central angle larger than 180 °. The motor according to any one of claims 1 to 6, wherein a radial dimension of the connection channel portion is larger than a radial dimension of the cooling channel. The motor according to claim 7, wherein a radial dimension of the connection channel portion is smaller than an axial dimension of the cooling channel. The motor according to any one of claims 1 to 8, wherein the connection channel portion is provided in the partition wall portion. The inverter accommodating portion is located on one side of the stator accommodating portion in a first direction orthogonal to the axial direction.
The motor according to claim 9, wherein the dimension of the partition wall in the first direction is larger as it is separated from the central axis in a second direction orthogonal to both the axial direction and the first direction. The portion of the partition wall portion located between the cooling flow passage and the inverter accommodation portion in the radial direction is located between the cooling flow passage and the stator accommodation portion in the partition wall portion. The motor according to any one of claims 1 to 10, wherein the dimension in the radial direction is smaller than that of the portion. A motor according to any one of the preceding claims, wherein the axial dimensions of the plurality of cooling channels are identical to one another. The motor according to any one of claims 1 to 12, wherein the radial dimensions of the plurality of cooling channels are the same.

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