JP2020162185A - motor - Google Patents

Abstract

To provide a motor having a structure in which efficiency of cooling a stator and an inverter part by a cooling passage can be improved.SOLUTION: An inverter housing part is positioned outside in a radial direction of a stator housing part. A housing has a peripheral wall part in a cylindrical shape surrounding a rotor and a stator at the outside in a radial direction of the rotor and the stator, and is a single member. The peripheral wall part has: a plurality of cooling flow passages arranged in an axial direction; a connection flow passage connecting the cooling flow passages adjacent to each other in the axial direction to each other; and a partition wall part partitioning the stator housing part and the inverter housing part. The cooling flow passages extend in a circumferential direction and are at least partially provided in the partition wall part. In the cooling flow passages adjacent to each other in the axial direction, refrigerants flowing through one cooling flow passage flow from one side in the circumferential direction toward the other side in the circumferential direction and flow through the connection flow passage part into the other cooling flow passage, and refrigerants flowing through the other cooling flow passage flow from the other side in the circumferential direction toward the one side in the circumferential direction.SELECTED DRAWING: Figure 5

Description

The present invention relates to a motor.

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

Japanese Unexamined Patent Publication No. 2015-104257

In the above-mentioned motor, it is required that the stator and the inverter device can be cooled efficiently. As a method of cooling the stator and the inverter device, it is conceivable to provide a cooling flow path through which the refrigerant flows in the housing. However, there are cases where sufficient cooling efficiency of the stator and the inverter device cannot be obtained simply by providing the cooling flow path in the housing.

In view of the above circumstances, one object of the present invention is to provide a motor having a structure capable of improving the cooling efficiency of the stator and the inverter portion by the cooling flow path.

One aspect of the motor of the present invention is a rotor having a motor shaft arranged along a central axis extending in one direction, a stator facing the rotor radially through a gap, and electrically the stator. The inverter accommodating portion includes a connected inverter portion, a stator accommodating portion accommodating the stator, and a housing having an inverter accommodating portion accommodating the inverter portion, and the inverter accommodating portion is located radially outside the stator accommodating portion. The housing has a tubular peripheral wall portion that surrounds the rotor and the stator on the radial outer side of the rotor and the inverter, and is a single member, and the peripheral wall portions are a plurality of arranged in the axial direction. The cooling flow path includes a connection flow path portion that connects the cooling flow paths adjacent to each other in the axial direction, and a partition wall portion that separates the stator accommodating portion and the inverter accommodating portion. In the cooling flow paths extending in the circumferential direction and at least partly provided on the partition wall portion and adjacent to each other in the axial direction, the refrigerant flowing in one of the cooling flow paths flows from one side in the circumferential direction to the circumferential direction. The refrigerant that flows toward the other side, flows into the other cooling flow path through the connection flow path portion, and flows in the other cooling flow path, flows from the other side in the circumferential direction to one side in the circumferential direction. It flows toward.

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

FIG. 1 is a perspective view showing the motor of the present embodiment. FIG. 2 is a diagram showing a motor of the present embodiment, and is a sectional view taken along line II-II in FIG. FIG. 3 is a diagram showing a motor of the present embodiment, and is a sectional view taken along line III-III in FIG. FIG. 4 is a view of the motor of the present embodiment as viewed from above. 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 the motor of the modified example in this embodiment.

The Z-axis direction shown in each figure 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 figure, and is a direction orthogonal to the vertical direction Z. In the following description, the 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 "one side in the axial direction", and the negative side in the axial direction Y is referred to as "the other side in the axial direction". The X-axis direction shown in each figure 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 called "one side in the width direction", and the negative side in the width direction X is called "the other side in the width direction". In this embodiment, the vertical direction Z corresponds to the first direction. The width direction X corresponds to the second direction.

Further, the radial direction centered on the central axis J is simply referred to as "diameter direction", and the circumferential direction centered on the central axis J is simply referred to as "circumferential direction θ". Further, in the circumferential direction θ, the side that advances clockwise when viewed from the other side in the axial direction toward one side in the axial direction, that is, the advancing side of the arrow indicating the circumferential direction θ in the figure is called “one side in the circumferential direction”. The side traveling counterclockwise, that is, the side opposite to the traveling side of the arrow indicating the circumferential direction θ in the figure is called "the other side in the circumferential direction".

The vertical direction, the upper side, and the lower side are names for simply explaining the relative positional relationship of each part, and the actual arrangement relationship, etc. is an arrangement relationship, etc. other than the arrangement relationship, etc. indicated by these names. You may.

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

As shown in FIG. 2, the housing 10 houses 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 square tube portion 10e.

The peripheral wall portion 10b has a tubular shape that surrounds the rotor 20 and the stator 30 on the radial outer side of the rotor 20 and the stator 30. In the present embodiment, the peripheral wall portion 10b has a substantially cylindrical shape centered on the central axis J. The peripheral wall portion 10b opens on one side in the axial direction. The peripheral wall portion 10b has a cooling portion 60 for cooling the stator 30 and the inverter unit 50.

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

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

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

The inverter accommodating portion 15 is located on the radial outer side of 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 accommodating portion 14 and the inverter accommodating portion 15 are partitioned in the vertical direction Z by the partition wall portion 10d. The partition wall portion 10d is an upper portion of the peripheral wall portion 10b. That is, the peripheral wall portion 10b has a partition wall portion 10d that partitions the stator accommodating portion 14 and the inverter accommodating portion 15.

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

The lid portion 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 square cylinder portion 10e. The lid portion 11 closes the opening on the upper side of the square cylinder portion 10e. In FIG. 4, the lid portion 11 is not shown. 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 the surface of the peripheral wall portion 10b and the square tube portion 10e on one side in the axial direction. The cover member 12 closes the opening on one side in the axial direction 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 12a 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 protruding from the peripheral edge portion of the output shaft hole 12a on the other side surface in the axial direction of the cover member 12 to the other side in the axial direction. The bearing holding portion 12b holds a bearing that supports the motor shaft 21 on one side in the axial direction with respect to the rotor core 22 described later.

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

The rotor 20 includes 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 on both sides in the axial direction. The end portion of the motor shaft 21 on one side in the axial direction projects from the opening on one side in the axial direction of the peripheral wall portion 10b toward one side in the axial direction. The end portion of the motor shaft 21 on one side in the axial direction passes through the output shaft hole 12a and projects toward one side in the axial direction from the cover member 12. The end of the motor shaft 21 on the other side in the axial direction is inserted into the sensor housing portion 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 provided in the rotor core 22 that penetrates the rotor core 22 in the axial direction Y. The first end plate 24 and the second end plate 25 have an annular plate shape that extends in the radial direction. The first end plate 24 and the second end plate 25 sandwich the rotor core 22 in the axial direction Y in a state of being in contact with the rotor core 22. The first end plate 24 and the second end plate 25 press the magnet 23 inserted in 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 with 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 portion 10b. The stator core 31 faces the outer side of the rotor core 22 in the radial direction with a gap.

The inverter unit 50 controls the electric 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 section 51 is housed in the inverter accommodating section 15. The inverter section 51 includes a first circuit board 51a and a second circuit board 51b. The first circuit board 51a and the second circuit board 51b have a plate shape whose plate surface is orthogonal to the vertical direction Z. The second circuit board 51b is arranged apart from the upper side of the first circuit board 51a. The first circuit board 51a and the second circuit board 51b are electrically connected. A coil wire 32a is connected to the first circuit board 51a via the connector terminal 53. As a result, the inverter section 51 is electrically connected to the stator 30.

As shown in FIGS. 2 and 4, the capacitor portion 52 has a rectangular parallelepiped shape that is long in the width direction X. The capacitor section 52 is housed in the inverter accommodating section 15. The capacitor portion 52 is arranged on the other side in the axial direction of the inverter portion 51. 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 section 52 is electrically connected to the inverter section 51. As shown in FIG. 2, the capacitor portion 52 is fixed to the upper surface of the partition wall portion 10d. The capacitor portion 52 comes into contact with the partition wall portion 10d.

As shown in FIG. 1, the connector portion 18 is provided on the surface of the square cylinder portion 10e on the other side in the width direction. An external power supply (not shown) is connected to the connector unit 18. Power is supplied to the inverter unit 50 from an external power source 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) type resolver. As shown in FIG. 2, the rotation detection unit 70 is housed in the sensor housing unit 10g. That is, the rotation detection unit 70 is arranged on the bottom wall portion 10a. The rotation detection unit 70 includes a detected unit 71 and a sensor unit 72.

The detected portion 71 is an annular shape extending in the circumferential direction θ. The detected portion 71 is fitted and fixed to the motor shaft 21. The detected portion 71 is made of a magnetic material. The sensor unit 72 is an annular shape that surrounds the radially outer side of the detected unit 71. The sensor unit 72 is fitted into the sensor housing unit 10 g. 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 sensor wiring 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 into the inverter accommodating portion 15 through the through hole that 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.

As the detected unit 71 rotates together with the motor shaft 21, an induced voltage is generated in the coil of the sensor unit 72 according to the circumferential position of the detected unit 71. The sensor unit 72 detects the rotation of the detected unit 71 by detecting the induced voltage. As a result, 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 side cooling flow path 61, a downstream side cooling flow path 62, and a connection flow path unit 63 as a plurality of cooling flow paths. That is, the peripheral wall portion 10b has an upstream side cooling flow path 61, a downstream side cooling flow path 62, and a connection flow path portion 63 as a plurality of cooling flow paths. In the present embodiment, the upstream cooling flow path 61 corresponds to the first cooling flow path. The downstream cooling flow path 62 corresponds to the second cooling flow path. 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 arranged in the axial direction Y. The upstream cooling flow path 61 and the downstream cooling flow path 62 are two cooling flow paths adjacent to each other in the axial direction Y. In the present embodiment, the upstream cooling flow path 61 is one of the two cooling flow paths adjacent to each other in the axial direction Y, which is located on one side in the axial direction. The downstream cooling flow path 62 is the other cooling flow path located on the other side in the axial direction of the two cooling flow paths adjacent to each other in the axial direction Y.

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

The upstream cooling flow path 61 extends in the circumferential direction θ. The upstream cooling flow path 61 has an upstream side flow path main body portion 61a, an inflow portion 61b, and an inflow port 61c. The upstream flow path main body 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 path main body 61a extends from the other side in the width direction of the peripheral wall portion 10b through the lower end portion of the peripheral wall portion 10b to the other side in the circumferential direction, and the upper end portion of the peripheral wall portion 10b. Extends to. The central angle φ of the upstream flow path main body 61a is larger than 180 °. As a result, the upstream cooling flow path 61 has an arc shape having a central angle larger than 180 °.

The inflow portion 61b is connected to the upstream side flow path main body portion 61a. More specifically, the inflow portion 61b is connected to the end portion on one side in the circumferential direction of the upstream side flow path main body portion 61a. The inflow portion 61b extends upward from one end in the circumferential direction of the upstream side flow path main body portion 61a. As shown in FIG. 5, the dimension of the inflow portion 61b in the axial direction Y is the same as the dimension of the upstream side flow path main body portion 61a in the axial direction Y. The dimension of the inflow portion 61b in the width direction X is larger than the dimension of the upstream side flow path main body portion 61a in the radial direction. As shown in FIG. 3, the upper end portion of the inflow portion 61b is located below the upper end portion of the upstream side flow path main body portion 61a. The inflow portion 61b is an end portion on one side in the circumferential direction of the upstream cooling flow path 61.

The inflow port 61c is provided in the inflow portion 61b. That is, the inflow port 61c 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 projects from the central portion of the inflow portion 61b in the axial direction Y and the vertical direction Z to the other side in the width direction. Refrigerant flows into the inflow port 61c. The cross-sectional shape of the inflow port 61c orthogonal to the width direction X is, for example, a circular shape. As shown in FIG. 3, an inflow pipe 16 is connected to the inflow port 61c. The inflow pipe 16 is inserted into a hole provided in the housing 10. The inflow pipe 16 projects from the housing 10 to the other side in the width direction.

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

In the present embodiment, the upper portion of the upstream flow path main body portion 61a and the inflow portion 61b are provided on the partition wall portion 10d. When viewed along the vertical direction Z, the portion of the upstream cooling flow path 61 provided on the partition wall portion 10d has a portion that overlaps with the inverter portion 51. As a result, the inverter section 51 can be more easily cooled by the upstream cooling flow path 61. In the present embodiment, of the portions of the upstream cooling flow path 61 provided in the partition wall portion 10d, the upper portion of the upstream side flow path main body 61a overlaps with the inverter portion 51 when viewed along the vertical direction Z.

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

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

As shown in FIG. 4, the maximum dimension of the upstream cooling flow path 61 in the width direction X is larger than the dimension of the width direction X of the second circuit board 51b and the dimension of the capacitor portion 52 in the width direction X. Although not shown, the maximum dimension of the upstream cooling flow path 61 in the width direction X is larger than the dimension of the first circuit board 51a in the width direction X. Therefore, it is easier to cool the inverter section 51 by the upstream cooling flow path 61. The maximum dimension of the upstream cooling flow path 61 in the width direction X is a portion located on one side in the width direction of the upstream cooling flow path 61 and a portion located on the other side in the width direction of the upstream cooling flow path 61. Is the distance between and in the width direction X. In the present embodiment, the maximum dimension of the upstream cooling flow path 61 in the width direction X corresponds to the outer diameter of the arc-shaped upstream cooling flow path 61.

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

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

The outflow port 62c is provided in the outflow portion 62b. That is, the outlet 62c is located at one end of the downstream cooling flow path 62 in the circumferential direction. The outflow port 62c projects from the central portion of the outflow portion 62b in the axial direction Y and the vertical direction Z to the other side in the width direction. Refrigerant flows out from the outflow port 62c. The cross-sectional shape of the outlet 62c orthogonal to the width direction X is, for example, a circular shape. The shape of the outflow port 62c is the same as the shape of the inflow port 61c. The inflow port 61c and the outflow port 62c are arranged at the same position in the vertical direction Z. The inflow port 61c and the outflow port 62c are arranged at intervals 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 arranged at the same position in the vertical direction Z. The inflow pipe 16 and the outflow pipe 17 are arranged at intervals in the axial direction Y.

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

In the present embodiment, the upper portion of the downstream flow path main body portion 62a and the outflow portion 62b are provided on the partition wall portion 10d. When viewed along the vertical direction Z, the portion of the downstream cooling flow path 62 provided on the partition wall portion 10d has a portion overlapping the inverter portion 51 and a portion overlapping the condenser portion 52. Therefore, the stator 30, the inverter section 51, and the condenser section 52 can be cooled by the refrigerant flowing in the downstream cooling flow path 62. Therefore, three portions can be cooled at the same time by one downstream cooling flow path 62, and cooling can be efficiently performed while reducing the number of cooling flow paths. Therefore, according to the present embodiment, the motor 1 having a structure capable of improving the cooling efficiency of the stator 30, the inverter section 51, and the capacitor section 52 by the cooling flow path can be obtained.

Further, as described above, in the present embodiment, the capacitor portion 52 comes into contact with the partition wall portion 10d. Therefore, the heat of the condenser portion 52 is likely to be released to the refrigerant in the downstream cooling flow path 62 through the partition wall portion 10d. Therefore, it is easier to cool the condenser portion 52 by the downstream cooling flow path 62.

In the present embodiment, the portion of the downstream cooling flow path 62 provided on the partition wall portion 10d is a single-layer flow path between the stator accommodating portion 14 and the inverter portion 51 in the radial direction, and is a stator accommodating portion. It is a single-layer flow path between the 14 and the capacitor portion 52 in the radial direction. That is, the portion of the downstream cooling flow path 62 provided between the stator accommodating portion 14 and the inverter portion 51 in the radial direction is only one continuous portion. Further, the portion of the downstream cooling flow path 62 provided between the stator accommodating portion 14 and the condenser portion 52 in the radial direction is only one continuous portion. Therefore, the configuration of the downstream cooling flow path 62 can be simplified as compared with the case where the flow paths of a plurality of layers are provided side by side in the radial direction. Further, the radial dimension 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 of the downstream cooling flow path 62 in the width direction X is larger than the dimension of the width direction X of the second circuit board 51b and the dimension of the capacitor portion 52 in the width direction X. Although not shown, the maximum dimension of the downstream cooling flow path 62 in the width direction X is larger than the dimension of the first circuit board 51a in the width direction X. Therefore, the inverter section 51 and the capacitor section 52 can be more easily cooled by the downstream cooling flow path 62. The maximum dimension of the downstream cooling flow path 62 in the width direction X is a portion located on one side in the width direction in the downstream cooling flow path 62 and a portion located on the other side in the width direction in the downstream cooling flow path 62. Is the distance between and in the width direction X. In the present embodiment, the maximum dimension of the downstream cooling flow path 62 in the width direction X corresponds to the outer diameter of the arc-shaped downstream cooling flow path 62. The maximum dimension of the downstream cooling flow path 62 in the width direction X is, for example, the same as the maximum dimension of the upstream cooling flow path 61 in the width direction X.

The axial direction Y dimension of the upstream cooling flow path 61 and the axial direction Y dimension of the downstream cooling flow path 62 are the same as each other. That is, the dimensions of the plurality of cooling channels in the axial direction Y are the same as each other. The radial dimension of the upstream cooling flow path 61 and the radial dimension of the downstream cooling flow path 62 are the same as each other. That is, the radial dimensions of the plurality of cooling channels are the same as each other.

The comparison of the axial direction Y dimension and the radial dimension of each cooling flow path includes, for example, a comparison between the main body portions of each flow path. That is, the dimension of the upstream flow path main body 61a in the axial direction Y and the dimension of the downstream flow path main body 62a in the axial direction Y are the same. The radial dimension of the upstream flow path main body 61a and the radial dimension of the downstream flow path main body 62a are the same as each other.

As shown in FIG. 6, in the portion 10j of the partition wall portion 10d located between the cooling flow path and the inverter accommodating portion 15 in the radial direction, the partition wall portion 10d is located between the cooling flow path and the inverter portion 51 in the radial direction. The portion 10i has a smaller radial dimension than the portion 10h located between the cooling flow path 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. As a result, the cooling flow path can be brought closer to the inverter section 51, and the inverter section 51 can be cooled more easily.

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

The portion 10j of the partition wall portion 10d located between the cooling flow path and the inverter accommodating portion 15 in the radial direction is located between the cooling flow path and the stator accommodating portion 14 of the partition wall portion 10d in the radial direction. 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 flow path can be brought closer to the inverter accommodating portion 15 than the stator accommodating portion 14, and the inverter accommodating portion 15 can be cooled more easily. Further, since the dimension L2 can be relatively increased, the radial dimension of the peripheral wall portion 10b in contact with the stator core 31 can be easily increased. As a result, the strength of holding the stator core 31 in the peripheral wall portion 10b can be relatively increased. As described above, the dimension L1, the dimension L2, and the dimension L3 satisfy the relationship of L1 <L3 <L2.

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

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 path portion 63 connects the upstream side cooling flow path 61 and the downstream side cooling flow path 62. More specifically, the connecting flow path portion 63 connects the end on the other side in the circumferential direction of the upstream cooling flow path 61 and the end on the other side in the circumferential direction of the downstream cooling flow path 62.

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

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

According to this embodiment, since a plurality of cooling channels are provided, the amount of refrigerant flowing in the cooling channels can be increased. This makes it easier to cool the stator 30 and the inverter section 51. Further, since a plurality of cooling flow paths are connected by the connection flow path portion 63, it is possible to flow the refrigerant through the plurality of cooling flow paths by providing one inflow port 61c and one outflow port 62c, which is convenient. is there. Further, since the cooling flow paths extending in the circumferential direction θ are arranged and connected in the axial direction Y, for example, as compared with the case where the cooling flow paths extending in the axial direction Y are arranged and connected in the circumferential direction θ, each cooling flow path and connection are connected. It is easy to manufacture the flow path portion 63.

Further, by arranging a plurality of cooling flow paths side by side in the axial direction Y, the dimension of the axial direction Y of each cooling flow path is reduced to reduce the flow path cross-sectional area of each cooling flow path, and a plurality of cooling flows. The dimension of the axial direction Y can be secured for the entire road. As a result, the flow velocity of the refrigerant flowing in each cooling flow path can be made relatively large, and the cooling efficiency of the stator 30 and the inverter section 51 by the refrigerant can be improved. Further, since the dimension of the axial direction Y can be secured for the entire plurality of cooling channels, a relatively wide range of the stator accommodating portion 14 and the inverter accommodating portion 15 can be cooled, and the stator 30 and the inverter portion 51 can be further cooled.

Further, since the dimension of the axial direction Y of each cooling flow path can be made relatively small, it is possible to suppress the flow of the refrigerant from stagnation in each cooling flow path. As a result, it is possible to suppress the change in the flow velocity of the refrigerant in each cooling flow path 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 the stator 30 and the inverter section 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 section 51 by the cooling flow path 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, it is possible to suppress the occurrence of a portion where the refrigerant stays in the upstream cooling flow path 61 and the downstream cooling flow path 62. As a result, it is possible to further suppress the flow of the refrigerant in each cooling flow path and further improve the cooling efficiency.

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

Further, according to the present embodiment, when viewed along the vertical direction Z, the portion of the upstream cooling flow path 61 provided on the partition wall portion 10d has a portion overlapping with the inverter portion 51 and is on the downstream side. The portion of the cooling flow path 62 provided on the partition wall portion 10d has a portion that overlaps with the condenser portion 52. Then, the refrigerant flowing in from the inflow port 61c flows through the upstream cooling flow path 61 before the downstream cooling flow path 62. Therefore, the inverter section 51 can be cooled by the refrigerant having a relatively low temperature flowing in from the inflow port 61c. This makes it easier to cool the inverter section 51. Since the inverter section 51 tends to generate a large amount of heat, it is easy to cool the inverter section 51, so that the motor 1 can be cooled more preferably.

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

Further, according to the present embodiment, the dimensions of the plurality of cooling channels in the axial direction Y are the same as each other. Therefore, it is easy to fabricate a plurality of cooling channels. In addition, it is easy to make the cross section of each cooling flow path the same. As a result, it is easy to make the flow velocity of the refrigerant the same in each cooling flow path, and it is easy to make the degree of cooling by each cooling flow path uniform. In the present embodiment, the axial direction Y dimension of the upstream cooling flow path 61 and the axial Y dimension of the downstream cooling flow path 62 are the same as each other. Therefore, the upstream cooling flow path 61 and the downstream cooling flow path 62 can be easily produced, and the degree of cooling by the upstream side cooling flow path 61 and the degree of cooling by the downstream side cooling flow path 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 as each other. Therefore, it is easy to fabricate a plurality of cooling channels. In addition, it is easy to make the cross section of each cooling flow path the same. As a result, it is easy to make the flow velocity of the refrigerant the same in each cooling flow path, and it is easy to make the degree of cooling by each cooling flow path more uniform.

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

As shown in FIG. 3, the radial dimension of the connecting flow path portion 63 is the radial dimension of the cooling flow path, that is, the radial dimension of the upstream cooling flow path 61 and the radial dimension of the downstream cooling flow path 62. Is larger than the size of. Therefore, the cross-sectional area of the flow path in the connecting flow path portion 63 is likely to be larger than the cross-section of the flow path of the upstream cooling flow path 61 and the cross-section of the flow path of the downstream cooling flow path 62. As a result, when the refrigerant flows from the connecting flow path portion 63 to the downstream cooling flow path 62, the flow path cross section becomes smaller, so that the flow velocity of the refrigerant can be improved. As a result, the flow velocity of the refrigerant in the downstream cooling flow path 62 can be easily increased, and the cooling efficiency of the downstream cooling flow path 62 can be further improved. Further, the pressure loss of the refrigerant flowing from the upstream cooling flow path 61 into the connection flow path portion 63 can be reduced.

As shown in FIG. 5, the radial dimension of the connecting flow path portion 63 is the axial direction Y dimension of the cooling flow path, that is, the axial direction Y dimension of the upstream side cooling flow path 61 and the downstream side cooling flow path 62. It is smaller than the dimension of the axial direction Y of. As a result, it is possible to prevent the connection flow path portion 63 from becoming too large in the radial direction. Therefore, it is possible to prevent the flow of the refrigerant from stagnation in the connection flow path portion 63.

The radial dimension of the connecting flow path portion 63 differs depending on the position in the circumferential direction θ. The radial dimension of the connecting flow path portion 63 is the largest in the central portion of the connecting flow path portion 63 in the circumferential direction θ, and decreases as the distance from the central portion on both sides in the circumferential direction θ increases. The central portion of the connecting flow path portion 63 in the circumferential direction θ and the end portion of the connecting flow path portion 63 on the other side in the circumferential direction are rounded.

As shown in FIG. 3, the connection flow path portion 63 is provided in the partition wall portion 10d. Therefore, the stator 30 and the inverter section 51 can be cooled by the refrigerant flowing through the connection flow path section 63. Therefore, the stator 30 and the inverter section 51 can be further cooled. Further, when the flow path cross section of the connecting flow path portion 63 is larger than the flow path cross section of the upstream cooling flow path 61 and the flow path cross section of the downstream cooling flow path 62 as in the present embodiment, the connecting flow The amount of the refrigerant flowing through the road 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 closer to the other side in the width direction. Here, as described above, the dimension of the partition wall portion 10d in the vertical direction Z increases as the distance from the central axis J in the width direction X increases. Therefore, the portion of the partition wall portion 10d closer to the other side in the width direction has a larger dimension in the vertical direction Z than the central portion of the partition wall portion 10d in the width direction X. Therefore, even when the radial dimension of the connecting flow path portion 63 is larger than the radial dimension of the cooling flow path as in the present embodiment, the connecting flow path portion 63 can be easily provided on the partition wall portion 10d.

In the present embodiment, the cooling unit 60 is formed by a sand mold portion 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 the sand mold forming the cooling portion 60. After the housing 10 is manufactured by sand casting, the sand mold for forming the cooling portion 60 is discharged from the discharge hole portion 19. The discharge hole portion 19 is connected to the cooling portion 60. The plug 80 is press-fitted into the discharge hole 19. The discharge hole portion 19 is closed by the plug body 80, and the refrigerant in the cooling portion 60 can be prevented from leaking to the outside of the housing 10.

(Modification example)
As shown in FIG. 7, in the housing 110 of the present modification, the cooling flow path and the condenser portion 52 are formed in the portion 110j of the partition wall portion 110d located between the cooling flow path and the inverter accommodating portion 15 in the radial direction. The portion 110h located between the radial directions is smaller in radial dimension than the portion 110i located between the cooling flow path and the inverter portion 51 in the radial direction. 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 closer to the condenser portion 52, and the condenser portion 52 can be more easily cooled.

In this modification, the portion 110i is a portion of the partition wall portion 110d located between the upstream cooling flow path 161 and the inverter portion 51 in the radial direction, and the downstream side cooling flow path 162 and the inverter of the partition wall portion 110d. A portion located between the portion 51 and the radial direction is included. The portion 110h includes a portion of the partition wall portion 110d located between the downstream cooling flow path 162 and the condenser portion 52 in the radial direction. In this modification, the upper surface of the partition wall portion 110d with which the capacitor portion 52 contacts is located below the upper surface of the partition wall portion 110d in which the inverter portion 51 is installed.

The portion 110k of the partition wall portion 110d located between the cooling flow path and the stator accommodating portion 14 in the radial direction is located between the cooling flow path and the inverter accommodating portion 15 of the partition wall portion 110d in the radial direction. The radial dimension is smaller than that of the portion 110j. 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 brought closer to the stator accommodating portion 14 than the inverter accommodating portion 15, and the stator accommodating portion 14 can be cooled more easily. As described above, 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 may be adopted. The cooling flow path 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 cooling channels may be provided. The radial dimensions of the plurality of cooling channels may differ from each other. The axial Y dimensions of the plurality of cooling channels may differ from each other. The shapes of the plurality of cooling channels may be different from each other. The portion of the cooling flow path provided on the partition wall portion may not overlap with the inverter portion or may not overlap with the condenser portion when viewed along the vertical direction Z.

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

The application of the motor of the above-described embodiment is not particularly limited. The motor of the above-described embodiment is mounted on a vehicle, for example. In addition, the above-mentioned configurations can be appropriately combined within a range that does not contradict each other.

1 ... motor, 10,110 ... housing, 10b ... peripheral wall part, 10d, 110d ... partition wall part, 14 ... stator housing part, 15 ... inverter housing part, 20 ... rotor, 21 ... motor shaft, 30 ... stator, 51 ... Inverter section, 52 ... Condenser section, 61, 161 ... Upstream cooling flow path (first cooling flow path), 61c ... Inflow port, 62, 162 ... Downstream side cooling flow path (second cooling flow path), 62c ... Flow Outlet, 63 ... Connection flow path, 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 with a motor shaft arranged along a central axis extending in one direction,
A stator facing the rotor in the radial direction through a gap,
An inverter unit that is electrically connected to the stator,
A housing having a stator accommodating portion for accommodating the stator and an inverter accommodating portion for accommodating the inverter portion,
With
The inverter accommodating portion is located on the radial outer side of the stator accommodating portion.
The housing has a tubular peripheral wall portion that surrounds the rotor and the stator on the radial outer side of the rotor and the stator, and is a single member.
The peripheral wall portion
With multiple cooling channels lined up in the axial direction,
A connecting flow path portion that connects the cooling flow paths adjacent to each other in the axial direction,
A partition wall portion that separates the stator accommodating portion and the inverter accommodating portion,
Have,
The cooling flow path extends in the circumferential direction, and at least a part thereof is provided on the partition wall portion.
In the cooling flow path adjacent to each other in the axial direction
The refrigerant flowing in one of the cooling flow paths 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 portion.
A motor in which the refrigerant flowing in the other cooling flow path flows from the other side in the circumferential direction toward one side in the circumferential direction. The motor according to claim 1, wherein the connecting flow path portion connects an end portion on the other side in the circumferential direction of the one cooling flow path and an end portion on one side in the circumferential direction of the other cooling flow path. Two cooling channels are provided.
The first cooling flow path, which is the cooling flow path located on one side in the axial direction of the two cooling flow paths, has an inflow port into which the refrigerant flows.
The second cooling flow path, which is the cooling flow path located on the other side in the axial direction of the two cooling flow paths, has an outlet through which the refrigerant flows out.
The inflow port is located at one end of the first cooling flow path in the circumferential direction.
The motor according to claim 1 or 2, wherein the outlet is located at one end of the second cooling flow path in the circumferential direction. Further provided with a capacitor section electrically connected to the inverter section
The capacitor portion is housed in the inverter accommodating portion and is arranged 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.
When viewed along the first direction, the portion of the first cooling flow path provided on the partition wall portion has a portion that overlaps with 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 portion has a portion that overlaps with the capacitor portion. In the portion of the partition wall portion located between the cooling flow path and the inverter accommodating portion in the radial direction, the 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 the dimension in the radial direction is smaller than the portion located between the path and the capacitor portion in the radial direction. The motor according to any one of claims 1 to 5, wherein the cooling flow path has an arc shape having a central angle larger than 180 °. The motor according to any one of claims 1 to 6, wherein the radial dimension of the connecting flow path portion is larger than the radial dimension of the cooling flow path. The motor according to claim 7, wherein the radial dimension of the connecting flow path portion is smaller than the axial dimension of the cooling flow path. The motor according to any one of claims 1 to 8, wherein the connection flow path portion is provided on 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 portion in the first direction increases as the distance from the central axis increases in the second direction orthogonal to both the axial direction and the first direction. The portion of the partition wall portion located between the cooling flow path and the inverter accommodating portion in the radial direction is located between the cooling flow path and the stator accommodating portion in the radial direction of the partition wall portion. The motor according to any one of claims 1 to 10, wherein the size in the radial direction is smaller than that of the portion. The motor according to any one of claims 1 to 11, wherein the dimensions of the plurality of cooling channels in the axial direction are the same as each other. The motor according to any one of claims 1 to 12, wherein the plurality of cooling flow paths have the same radial dimensions.

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