Rotating electrical machine

Abstract

A rotating electrical machine according to the present disclosure comprises: a motor comprising a rotary shaft, a rotor which is fixed to the rotary shaft, a stator which is disposed outside the rotor, a winding which is wound around the stator, and a motor case which houses the rotary shaft, the rotor, and the stator; a control unit which controls the motor; and a housing which is disposed between the stator and the control unit in an axial direction along the rotary shaft and has a shaft through-hole into which the rotary shaft is inserted. The control unit has a substrate on which a heat generation part is mounted, and the housing has a main body part and a case attachment part which protrudes from the main body part toward the stator side and is attached to the motor case. The housing has a heat transfer surface which faces the substrate and is disposed at a position overlapping with the heat generation part in the axial direction, a heat dissipation material which thermally connects the heat transfer surface and the heat generation part is disposed between the heat transfer surface and the heat generation part, and at least a portion of the heat transfer surface is disposed at a position overlapping with the case attachment part in the axial direction.

Description

rotating electrical machines

[0001] The present disclosure relates to a rotating electric machine.

[0002] A rotating electric machine having a motor and a control unit for controlling the motor has been known. The control unit has a heat-generating portion, such as a switching element of a power circuit, that generates heat when a current flows through it. Patent Document 1 discloses a structure in which a heat sink is provided above a substrate on which the power circuit is mounted in order to dissipate the heat generated in the heat-generating portion to the outside of the rotating electric machine.

[0003] International Publication No. 2022 / 230007

[0004] In the structure of Patent Document 1, an additional heat sink is provided to dissipate heat generated in the heat-generating portion to the outside of the rotating electric machine, which increases the size of the rotating electric machine and also increases the cost of the rotating electric machine due to the increased number of parts. There is a demand for effectively dissipating heat generated in the heat-generating portion to the outside of the rotating electric machine while suppressing an increase in the size of the rotating electric machine.

[0005] In consideration of the above circumstances, the present disclosure aims to provide a rotating electric machine that can effectively dissipate heat generated in heat-generating parts to the outside of the rotating electric machine while suppressing an increase in the size of the rotating electric machine.

[0006] One aspect of a rotating electric machine according to the present disclosure includes a motor including a rotating shaft, a rotor fixed to the rotating shaft, a stator arranged outside the rotor, windings wound on the stator, and a motor case accommodating the rotating shaft, the rotor, and the stator; a control unit for controlling the motor; and a housing arranged between the stator and the control unit in an axial direction along the rotating shaft and having a shaft through hole through which the rotating shaft is inserted, wherein the control unit has a board on which a heat generating portion is mounted, the housing having a main body and a case mounting portion that protrudes from the main body toward the stator and is attached to the motor case, the housing has a heat transfer surface that faces the board and is positioned so as to overlap with the heat generating portion in the axial direction, and a heat dissipation material is provided between the heat transfer surface and the heat generating portion to thermally connect the heat transfer surface and the heat generating portion, and at least a portion of the heat transfer surface is positioned so as to overlap with the case mounting portion in the axial direction.

[0007] According to the present disclosure, it is possible to provide a rotating electric machine that can effectively dissipate heat generated in a heat-generating portion to the outside of the rotating electric machine while suppressing an increase in the size of the rotating electric machine.

[0008] Fig. 1 is a cross-sectional view of a rotating electric machine according to embodiment 1. Fig. 2 is a cross-sectional view of a control unit according to embodiment 1. Fig. 3 is a plan view of a board according to embodiment 1. Fig. 4 is a plan view of a housing according to embodiment 1. Fig. 5 is a plan view of a board according to embodiment 2. Fig. 6 is a plan view of a housing according to embodiment 2. Fig. 7 is a diagram showing a connector according to embodiment 3. Fig. 8 is a partial cross-sectional view of a control unit according to embodiment 4. Fig. 9 is a partial cross-sectional view of a control unit according to embodiment 5.

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the scope of the present disclosure is not limited to the following embodiments and can be modified as desired within the scope of the technical concept of the present disclosure.

[0010] 1 is a cross-sectional view of a rotating electric machine 100 according to embodiment 1. The rotating electric machine 100 may be an inner rotor type generator or an electric motor, but in embodiment 1, an electric motor will be used as an example.

[0011] As shown in Fig. 1, the rotating electric machine 100 includes a motor 2 and a control unit 1 that controls the motor 2. The control unit 1 includes a circuit board 4, a connector 5, a cover 1a, etc. The motor 2 is a multi-phase winding motor. The motor 2 includes a rotating shaft 21 (output shaft), a rotor 22, a stator 23, a motor case 3, etc. A housing 6 is provided between the circuit board 4 and the stator 23.

[0012] In the following description, the direction along the central axis O of the rotating shaft 21 is referred to as the axial direction Z. The control unit 1 and the motor 2 are arranged side by side in the axial direction Z. In the axial direction Z, the side where the control unit 1 is located is referred to as the upper side, and the side where the motor 2 is located is referred to as the lower side. The view from the axial direction Z is referred to as a plan view. A view from the axial direction Z is referred to as a plan view. Note that the axial direction Z does not have to coincide with the vertical direction. A direction perpendicular to the axial direction Z is referred to as the first orthogonal direction X. A direction perpendicular to both the axial direction Z and the first orthogonal direction X is referred to as the second orthogonal direction Y.

[0013] The rotor 22 is fixed to the rotating shaft 21. Plural pairs of permanent magnets (not shown) are arranged on the outer circumferential surface of the rotor 22. The stator 23 is provided so as to surround the outer periphery of the rotor 22. The stator 23 is arranged radially outward of the rotor 22 with a gap therebetween. A plurality of windings 24a are wound around the stator 23. Specifically, bobbins 24b and 24c are fixed to the stator 23, and the plurality of windings 24a are wound around the bobbins 24b and 24c. The plurality of windings 24a include windings 24a corresponding to each phase of the motor 2. For example, if the motor 2 is a three-phase motor, the plurality of windings 24a may include a winding 24a corresponding to a U-phase, a winding 24a corresponding to a V-phase, and a winding 24a corresponding to a W-phase. A sensor rotor 25 is attached to the upper end of the rotating shaft 21.

[0014] An annular terminal 27 and a plurality of motor terminal portions 28 are provided above the stator 23. The annular terminal 27 is disposed near the winding 24a. The annular terminal 27 is connected to an end of the winding 24a. The plurality of motor terminal portions 28 extend upward (toward the control unit 1) from the annular terminal 27. The plurality of motor terminal portions 28 are electrically connected to the ends of the plurality of windings 24a via the annular terminal 27.

[0015] The motor case 3 has a cylindrical shape with a bottom. The motor case 3 houses the rotating shaft 21, rotor 22, and stator 23. The motor case 3 is made of metal. For example, the motor case 3 is made of a die-cast aluminum alloy. The stator 23 is fixed to the inner surface of the motor case 3. A through-hole 3a is formed in the center of the bottom of the motor case 3 in a plan view, penetrating the bottom of the motor case 3 in the axial direction Z. A fitting recess 3b into which the housing 6 is fitted is provided at the upper end of the motor case 3.

[0016] The housing 6 is provided above the stator 23. The housing 6 is fitted into the fitting recess 3b of the motor case 3. The housing 6 is a lid that closes the upper opening of the motor case 3. The housing 6 is made of metal. For example, the housing 6 is made of a die-cast aluminum alloy. The housing 6 forms the boundary between the motor 2 and the control unit 1. A shaft through-hole 61 that passes through the housing 6 in the axial direction Z is formed in the center of the housing 6 in a plan view. In a plan view, the shaft through-hole 61 has a circular shape centered on the central axis O.

[0017] The upper end of the rotating shaft 21 and the sensor rotor 25 are disposed inside the shaft through-hole 61. A first bearing 26a is provided in the shaft through-hole 61. The lower end of the rotating shaft 21 is inserted into the through-hole 3a. A second bearing 26b is provided in the through-hole 3a. The first bearing 26a and the second bearing 26b support the rotating shaft 21 rotatably.

[0018] The cover 1a covers the circuit board 4 and the housing 6 from above. The cover 1a is attached to the motor case 3. The circuit board 4 is disposed inside the cover 1a. The circuit board 4 and the cover 1a are disposed spaced apart from each other. The circuit board 4 is disposed above the housing 6. As shown in FIG. 2, the circuit board 4 has a first surface 4a facing the housing 6 and a second surface 4b on the opposite side. The first surface 4a faces downward, and the second surface 4b faces upward. The housing 6 has an opposing surface 6a facing the circuit board 4. The opposing surface 6a faces upward.

[0019] 1 , power from an external power supply and various signals from an external control device or the like are supplied to the substrate 4 via a connector 5. The connector 5 has a plurality of power connection terminals 5a for supplying power from an external power supply provided outside the rotating electric machine 100 to the substrate 4, and a plurality of signal connection terminals 5b for supplying various signals from a control device or the like provided outside the rotating electric machine 100 to the substrate 4. The connector 5 is disposed in a position that does not make contact with the motor 2. In the illustrated example, the connector 5 is disposed below the substrate 4. The plurality of power connection terminals 5a and the plurality of signal connection terminals 5b are connected to the substrate 4 from below.

[0020] The substrate 4 is disposed so as to be substantially perpendicular to the axial direction Z. That is, as shown in FIG.

[0021] A control circuit 41, a power circuit 42, a filter circuit 43, etc. are mounted on the substrate 4. The substrate 4 has a control circuit mounting region R1 where the control circuit 41 is mounted, a power circuit mounting region R2 where the power circuit 42 is mounted, and a filter circuit region R3 where the filter circuit 43 is mounted.

[0022] The substrate 4 is formed with a plurality of power connection holes 44a connected to the plurality of power connection terminals 5a, and a plurality of signal connection holes 44b connected to the plurality of signal connection terminals 5b. The plurality of power connection holes 44a are arranged at positions overlapping the plurality of power connection terminals 5a in the axial direction Z. The plurality of signal connection holes 44b are arranged at positions overlapping the plurality of signal connection terminals 5b in the axial direction Z. The plurality of power connection holes 44a and the plurality of signal connection holes 44b are arranged at one end of the substrate 4 in the first orthogonal direction X. The power connection terminals 5a are inserted into the power connection holes 44a, and the signal connection terminals 5b are inserted into the signal connection holes 44b. The power connection terminals 5a are electrically connected to a conductive layer formed on the inner surface of the power connection holes 44a, for example, by soldering. The signal connection terminals 5b are electrically connected to a conductive layer formed on the inner surface of the signal connection holes 44b, for example, by soldering.

[0023] The substrate 4 is formed with a plurality of motor connection holes 45 that are connected to the plurality of motor terminal portions 28. The plurality of motor connection holes 45 are arranged at positions corresponding to the plurality of motor terminal portions 28. For example, the plurality of motor connection holes 45 are arranged at positions that overlap with the tip ends of the plurality of motor terminal portions 28 in the axial direction Z. The plurality of motor connection holes 45 are arranged at the other end of the substrate 4 in the first orthogonal direction X. The motor terminal portions 28 are inserted through the motor connection holes 45. The motor terminal portions 28 are electrically connected to a conductive layer formed on the inner surface of the motor connection holes 45, for example, by soldering.

[0024] The substrate 4 has a plurality of mounting holes 46 through which screws 70 (see FIG. 2) are inserted to fix the substrate 4 to the housing 6. The mounting holes 46 are arranged on the outer edge of the substrate 4.

[0025] Various signals are input to the control circuit 41 from an external control device or the like via the signal connection terminals 5b. The control circuit 41 processes these signals. The control circuit 41 controls the power circuit 42 based on the processed signals. The control circuit 41 also processes information obtained from the substrate 4 and outputs the information to the external control device or the like. The control circuit 41 includes electronic components such as a CPU (Central Processing Unit) 41a and an IC (Integrated Circuit) 41b, as well as a wiring pattern 41c that connects these electronic components. The wiring pattern 41c is also connected to the signal connection holes 44b. Note that FIG. 3 shows a portion of the wiring pattern 41c. The CPU 41a and IC 41b are disposed on the first surface 4a of the substrate 4.

[0026] The power circuit 42 supplies current to the multiple windings 24a to drive the motor 2. The power circuit 42 includes electronic components such as a switching element 42a, a shunt resistor 42b, a capacitor 42c, and a choke coil (not shown), as well as a wiring pattern 42d that connects these electronic components. The wiring pattern 42d is also connected to the motor connection hole 45. Note that FIG. 3 shows a portion of the wiring pattern 42d. The switching element 42a is disposed on the second surface 4b of the substrate 4. The shunt resistor 42b and the capacitor 42c are disposed on the first surface 4a of the substrate 4.

[0027] The switching element 42a and the shunt resistor 42b of the power circuit 42 are heat-generating parts that generate heat when a current flows through them. The heat-generating parts may also include the wiring pattern 42d of the power circuit 42, the CPU 41a and the IC 41b of the control circuit 41, etc.

[0028] The filter circuit 43 performs noise filtering. The filter circuit 43 includes filter electronic components 43a such as noise filtering capacitors. The specifications of the filter electronic components 43a are determined according to EMC (Electromagnetic Compatibility) requirements. In the illustrated example, the filter electronic components 43a are disposed on the second surface 4b of the substrate 4. The filter electronic components 43a may also be disposed on the first surface 4a of the substrate 4.

[0029] A rotation sensor 47 is mounted on the first surface 4a of the substrate 4. In a plan view, the rotation sensor 47 is disposed in the center of the substrate 4. The rotation sensor 47 is disposed in a position facing the sensor rotor 25 in the axial direction Z. The rotation sensor 47 detects a signal from the sensor rotor 25 and converts it into an electrical signal.

[0030] In plan view, the power circuit 42 is disposed around the rotation sensor 47. That is, the power circuit mounting region R2 is disposed around the rotation sensor 47. In plan view, a portion of the power circuit 42 (in the illustrated example, the switching element 42a and the shunt resistor 42b) is disposed between the rotation sensor 47 and the motor connection hole 45. The switching element 42a is disposed near the motor connection hole 45. This makes it possible to minimize the length of the portion of the wiring pattern 42d that connects the switching element 42a and the motor connection hole 45.

[0031] In plan view, the control circuit 41 is disposed between the power circuit 42 and the signal connection holes 44b. That is, the control circuit mounting region R1 is disposed between the power circuit mounting region R2 (power circuit 42) and the signal connection holes 44b. This allows the length of the portion of the wiring pattern 41c connecting the control circuit 41 and the signal connection holes 44b to be reduced. The wiring pattern 41c is affected by noise generated in the power circuit 42, but reducing the length of the wiring pattern 41c reduces the influence of this noise. Furthermore, because the influence of noise on the wiring pattern 41c can be reduced, the number and size of the filter electronic components 43a of the filter circuit 43 that performs noise filtering can be reduced.

[0032] Electric power from an external power source is supplied to the power circuit 42 via the power connection terminal 5a and the power connection hole 44a. The power circuit 42 outputs AC current by switching the ON / OFF state of the switching element 42a. The output current is supplied to the windings 24a via the motor connection hole 45 and the plurality of motor terminals 28, causing the rotating shaft 21 to rotate.

[0033] As shown in FIG. 2 , the housing 6 has a main body 60 and a case mounting portion 62 that protrudes downward (toward the stator 23) from the main body 60. In a plan view, the case mounting portion 62 has a circular shape centered on the central axis O. The case mounting portion 62 is fitted into the fitting recess 3b of the motor case 3 and mechanically fixed to the fitting recess 3b. For example, the case mounting portion 62 is fixed by being press-fitted into the fitting recess 3b. The case mounting portion 62 may also be fixed to the fitting recess 3b using a screw. To ensure the mechanical strength of the case mounting portion 62, the case mounting portion 62 is formed to have a large thickness. The case mounting portion 62 is also thermally connected to the fitting recess 3b.

[0034] As shown in FIG. 4, the housing 6 has a shaft through-hole 61, a capacitor storage hole 64, a plurality of motor terminal through-holes 65, a board mounting portion 66, and the like.

[0035] The multiple motor terminal through holes 65 are arranged at positions overlapping with the multiple motor connection holes 45 in the axial direction Z. The multiple motor terminal through holes 65 penetrate the housing 6 in the axial direction Z. The multiple motor terminal through holes 65 are arranged at the other end of the housing 6 in the first orthogonal direction X. In plan view, the multiple motor terminal through holes 65 are arranged between the shaft through hole 61 and the outer peripheral surface of the case mounting portion 62. The multiple motor terminal portions 28 are inserted into the multiple motor terminal through holes 65, respectively.

[0036] The capacitor storage hole 64 is disposed at a position facing the capacitor 42c in the axial direction Z. In this embodiment, the capacitor storage hole 64 is a cylindrical recess recessed downward from the opposing surface 6a of the housing 6. The capacitor storage hole 64 has a bottom 64a facing the board 4. The capacitor storage hole 64 is disposed at a position overlapping with the case mounting portion 62 in the axial direction Z. In a plan view, the capacitor storage hole 64 is disposed between the shaft through-hole 61 and the outer peripheral surface of the case mounting portion 62. When the board 4 is attached to the housing 6, at least a portion of the capacitor 42c is stored in the capacitor storage hole 64. At this time, a gap is formed between the capacitor storage hole 64 and the capacitor 42c.

[0037] The board mounting portion 66 protrudes from the opposing surface 6a toward the board 4. The upper surface of the board mounting portion 66 abuts against the first surface 4a of the board 4. The board mounting portion 66 has a fastening hole 66a into which a screw 70 is fastened. The fastening hole 66a is disposed at a position overlapping with the mounting hole 46 in the axial direction Z. The board 4 is fixed to the housing 6 by inserting the screw 70 into the mounting hole 46 and fastening it into the fastening hole 66a.

[0038] The rotating electric machine 100 has a heat dissipation structure that dissipates heat generated by a heat-generating portion mounted on the substrate 4 to the outside. More specifically, the housing 6 is positioned so as to overlap the heat-generating portion in the axial direction Z and has a heat transfer surface for transferring heat generated by the heat-generating portion to the housing 6. The heat transfer surface includes a surface 63a1 of the flat portion 63a, a surface 63b1 of the recessed portion 63b, and a surface 63c1 of the protruding portion 63c, which will be described later. A gap is formed between the heat transfer surface and the heat-generating portion, and a heat dissipation material 7 is provided in this gap. The heat dissipation material 7 thermally connects the heat-generating portion and the housing 6. The heat dissipation material 7 is insulating and has high thermal conductivity. The thermal conductivity of the heat dissipation material 7 is significantly greater than that of air. The heat dissipation material 7 is, for example, a silicone-based thermal grease.

[0039] The heat dissipation structure will now be described in detail. The housing 6 is formed with flat portions 63a, recessed portions 63b, and protruding portions 63c in accordance with the shape and arrangement of the heat generating portion. The formation of the flat portions 63a, recessed portions 63b, and protruding portions 63c adjusts the size of the gap between the heat transfer surface and the heat generating portion.

[0040] Specifically, a flat portion 63a that is flush with the opposing surface 6a is provided in a portion overlapping the switching element 42a in the axial direction Z. A gap is provided between the flat portion 63a and the switching element 42a, and a heat dissipation material 7 is provided in this gap. A surface 63a1 of the flat portion 63a constitutes the heat transfer surface. The surface 63a1 of the flat portion 63a is thermally connected to the switching element 42a via the heat dissipation material 7 and the substrate 4. A recess 63b recessed from the opposing surface 6a is provided in a portion overlapping the shunt resistor 42b in the axial direction Z. A gap is provided between the recess 63b and the shunt resistor 42b, and a heat dissipation material 7 is provided in this gap. A surface 63b1 of the recess 63b facing the substrate 4 constitutes the heat transfer surface. The surface 63b1 of the recess 63b is thermally connected to the shunt resistor 42b via the heat dissipation material 7. In addition, when the heat generating portion includes the wiring pattern 42d, the heat transfer surface may include a portion of the opposing surface 6a that overlaps with the wiring pattern 42d in the axial direction Z.

[0041] A protrusion 63c protruding from the opposing surface 6a is provided in a portion overlapping with the CPU 41a and IC 41b in the axial direction Z. A gap is provided between the protrusion 63c and the CPU 41a and IC 41b, and a heat dissipation material 7 is provided in this gap. A surface 63c1 of the protrusion 63c facing the substrate 4 is thermally connected to the CPU 41a and IC 41b via the heat dissipation material 7. When the heat-generating portion includes the CPU 41a and IC 41b, the heat transfer surface may include the surface 63c1 of the protrusion 63c.

[0042] Heat generated by heat-generating components arranged on the first surface 4a of the substrate 4, such as the shunt resistor 42b, CPU 41a, and IC 41b, is transferred to the heat transfer surface (surface 63b1 and surface 63c1) via the heat dissipation material 7. Heat generated by heat-generating components arranged on the second surface 4b of the substrate 4, such as the switching element 42a, is transferred to the heat transfer surface (surface 63a1) via the substrate 4 and the heat dissipation material 7. In the following description, this is collectively referred to as "heat generated by the heat-generating components being transferred to the heat transfer surface via the heat dissipation material 7." The heat transferred to the heat transfer surface in this manner is transferred to the motor case 3 via the housing 6 and dissipated from the motor case 3 to the outside air. By providing the heat dissipation material 7, heat generated by the heat-generating components can be efficiently transferred to the heat transfer surface via the heat dissipation material 7.

[0043] Here, in a plan view, the heat transfer surface is positioned to overlap the case mounting portion 62 and its vicinity. In a plan view, most of the heat transfer surface, including portions of the surfaces 63a1, 63b1, and 63c1, is positioned to overlap the case mounting portion 62. That is, in a plan view, most of the heat transfer surface is positioned between the shaft through hole 61 and the outer peripheral surface of the case mounting portion 62. Here, the majority of the heat transfer surface refers to, for example, 70% or more of the entire heat transfer surface. Compared to portions of the housing 6 where the case mounting portion 62 is not formed, the portions of the housing 6 where the case mounting portion 62 is formed are thicker and have a larger volume, making it easier to absorb heat generated in the heat-generating portion. By arranging the heat transfer surface as described above, heat generated in the heat-generating portion can be more efficiently transferred to the motor case 3. Note that a portion of the heat transfer surface may be positioned near the motor terminal through hole 65.

[0044] An example of an assembly process for the rotating electric machine 100 will be described. The rotating shaft 21, rotor 22, stator 23, etc. are assembled into the motor case 3. At this time, the sensor rotor 25 attached to the upper end of the rotating shaft 21 and the multiple motor terminal portions 28 extending from the annular terminal 27 can be seen through the upper opening of the motor case 3. In this state, the case mounting portion 62 of the housing 6 is attached to the fitting recess 3b of the motor case 3. At this time, the upper end of the rotating shaft 21, to which the sensor rotor 25 is attached, is inserted into the shaft through-hole 61 of the housing 6. The multiple motor terminal portions 28 are inserted into the multiple motor terminal through-holes 65 of the housing 6.

[0045] Next, the heat dissipation material 7 is applied to the heat transfer surface of the housing 6. Thereafter, the substrate 4 is attached to the housing 6. Specifically, the first surface 4a of the substrate 4 is abutted against the upper surface of the substrate attachment portion 66, and screws 70 are inserted into the attachment holes 46 and fastened to the fastening holes 66a, thereby fixing the substrate 4 to the housing 6. At this time, the rotation sensor 47 and the sensor rotor 25 face each other in the axial direction Z with a gap therebetween. In addition, the multiple motor terminal portions 28 are inserted into the multiple motor connection holes 45 of the substrate 4. The heat dissipation material 7 is spread between the heat-generating portion and the heat transfer surface, and the heat-generating portion and the heat transfer surface are thermally connected via the heat dissipation material 7.

[0046] As described above, the rotating electric machine 100 according to this embodiment includes the motor 2, the control unit 1 that controls the motor 2, and the housing 6 that is disposed between the stator 23 and the control unit 1 in the axial direction Z and has a shaft through-hole 61 through which the rotating shaft 21 is inserted. The control unit 1 has a substrate 4 on which a heat-generating portion is mounted. The housing 6 has a main body 60 and a case attachment portion 62 that protrudes from the main body 60 toward the stator 23 and is attached to the motor case 3. The housing 6 has a heat transfer surface that faces the substrate 4 and is positioned so as to overlap the heat-generating portion in the axial direction Z. A heat dissipation material 7 that thermally connects the heat transfer surface and the heat-generating portion is provided between the heat transfer surface and the heat-generating portion. At least a portion of the heat transfer surface is positioned so as to overlap the case attachment portion 62 in the axial direction Z.

[0047] Heat generated by the heat-generating portion can be transferred to the heat transfer surface via the heat dissipation material 7. The heat transferred to the heat transfer surface is transferred to the motor case 3 via the housing 6 and then dissipated from the motor case 3 to the outside of the rotating electric machine 100. Therefore, heat generated in the heat-generating portion can be dissipated to the outside of the rotating electric machine 100. Furthermore, at least a portion of the heat transfer surface is positioned so as to overlap with the case mounting portion 62 in the axial direction Z. Compared to a portion of the housing 6 where the case mounting portion 62 is not formed, the portion of the housing 6 where the case mounting portion 62 is formed is thicker, making it easier to absorb heat generated in the heat-generating portion. By arranging the heat transfer surface as described above, the heat transfer path from the heat-generating portion to the case mounting portion 62 can be shortened. Therefore, without providing an additional heat sink or the like, heat generated in the heat-generating portion can be effectively transferred to the motor case 3 via the housing 6 and efficiently dissipated to the outside of the rotating electric machine 100. Therefore, the rotating electric machine 100 can be made smaller in size than when a heat sink or the like is provided. That is, according to the rotating electric machine 100 according to this embodiment, it is possible to effectively dissipate heat generated in the heat-generating portion to the outside of the rotating electric machine 100 while suppressing an increase in the size of the rotating electric machine 100. In particular, by arranging most of the heat transfer surface at a position overlapping with the case mounting portion 62 in the axial direction Z, it is possible to more efficiently transfer heat generated in the heat-generating portion to the motor case 3.

[0048] A sensor rotor 25 is attached to the rotating shaft 21, and a rotation sensor 47 is mounted on the substrate 4 so as to face the sensor rotor 25 in the axial direction Z. A motor connection hole 45 is formed in the substrate 4 and connected to a motor terminal portion 28 extending from the winding 24a. A power circuit 42 including a capacitor 42c, a shunt resistor 42b serving as a heat-generating portion, and a switching element 42a is mounted on the substrate 4. When viewed from the axial direction Z, at least a portion of the power circuit 42 is disposed between the motor connection hole 45 and the rotation sensor 47. By arranging the power circuit 42 as described above, the length of the wiring pattern 42d, which is the path from the power circuit 42 to the motor connection hole 45, can be shortened. Because the wiring pattern 42d generates heat when the motor 2 is driven, shortening the length of the wiring pattern 42d can reduce the amount of heat generated by the entire substrate 4. In particular, for example, when the switching element 42a is disposed near the motor connection hole 45, the length of the portion of the wiring pattern 42d that connects the switching element 42a and the motor connection hole 45 can be minimized. Therefore, heat generation in the wiring pattern 42d can be more effectively suppressed, and the amount of heat generated by the entire substrate 4 can be more effectively reduced.

[0049] The capacitor 42c and the shunt resistor 42b are disposed on the first surface 4a of the substrate 4, and the switching element 42a is disposed on the second surface 4b of the substrate 4. The housing 6 is provided with a capacitor storage hole 64 that is disposed at a position overlapping the case mounting portion 62 in the axial direction Z and that stores at least a portion of the capacitor 42c. For example, if the capacitor 42c is disposed on the second surface 4b of the substrate 4 or if the housing 6 does not have the capacitor storage hole 64, the capacitor 42c protrudes from the substrate 4, increasing the size of the rotating electric machine 100 by the height of the capacitor 42c. By disposing the capacitor 42c on the first surface 4a of the substrate 4 and storing the capacitor 42c in the capacitor storage hole 64, the increase in size of the rotating electric machine 100 due to the capacitor 42c protruding from the substrate 4 can be suppressed. The capacitor storage hole 64 is disposed at a position overlapping the case mounting portion 62 in the axial direction Z. The portion of the housing 6 where the case mounting portion 62 is formed is thicker than the portion of the housing 6 where the case mounting portion 62 is not formed, so the height (depth) of the capacitor storage hole 64 can be ensured and the capacitors 42c can be reliably accommodated in the capacitor storage hole 64. Furthermore, capacitors with a greater height can be used as the capacitors 42c, and the capacitance per capacitor can be increased, so the mounting area of ​​the capacitors 42c on the board 4 can be reduced.

[0050] The housing 6 also has a recess 63b recessed from the opposing surface 6a of the housing 6 at a position overlapping the shunt resistor 42b in the axial direction Z. A surface 63b1 of the recess 63b facing the substrate 4 is included in the heat transfer surface. The recess 63b formed in the housing 6 makes it possible to adjust the distance between the heat transfer surface and the heat generating portion. Therefore, heat generated by the heat generating portion can be transferred more efficiently to the heat transfer surface via the heat dissipation material 7.

[0051] The control unit 1 also includes a connector 5 having a power connection terminal 5a for receiving power from an external source and a signal connection terminal 5b for receiving signals from an external source. The board 4 is formed with power connection holes 44a for connecting with the power connection terminal 5a and signal connection holes 44b for connecting with the signal connection terminal 5b, and is also mounted with a control circuit 41 for controlling the power circuit 42. When viewed from the axial direction Z, the control circuit 41 is disposed between the signal connection holes 44b and the power circuit 42. By arranging the control circuit 41 as described above, the length of the wiring pattern 41c, which is the path from the control circuit 41 to the signal connection holes 44b, can be minimized. The wiring pattern 41c is affected by noise generated in the power circuit 42, but reducing the length of the wiring pattern 41c can reduce the influence of this noise. Furthermore, because the influence of noise on the wiring pattern 41c is reduced, even if a filter circuit 43 for performing noise filtering is mounted on the board 4, the number and size of the filter electronic components 43a of the filter circuit 43 can be reduced. Therefore, the mounting area of ​​the control circuit 41 and the filter circuit 43 on the substrate 4 can be reduced. As a result, the substrate 4 can be made smaller, and the rotating electric machine 100 can be made smaller. Note that, for example, when a power circuit is disposed between a signal connection hole and the control circuit, the wiring pattern that is the path from the control circuit to the signal connection hole must pass around the power circuit, and the length of the wiring pattern also becomes long, making the wiring pattern susceptible to noise generated in the power circuit. As a result, the number and size of the mounted components of the filter circuit must also be increased, which increases the size of the substrate and the rotating electric machine.

[0052] Furthermore, the capacitor storage hole 64 has a bottom 64a facing the circuit board 4. The bottom 64a separates the internal space of the capacitor storage hole 64 from the internal space of the motor 2. Therefore, even if foreign matter such as dust is generated on the capacitor 42c side, the foreign matter can be prevented from entering the motor 2. Furthermore, since the portion of the housing 6 where the case mounting portion 62 is formed is thicker than the portion of the housing 6 where the case mounting portion 62 is not formed, the capacitor storage hole 64 with the bottom 64a can be easily formed.

[0053] Second Embodiment Next, a rotating electric machine according to a second embodiment will be described. The rotating electric machine according to this embodiment has the same basic configuration as the rotating electric machine according to the first embodiment, and therefore the following description will focus on the differences.

[0054] Fig. 5 is a plan view of the substrate 4 according to the second embodiment. Fig. 6 is a plan view of the housing 6 according to the second embodiment.

[0055] As shown in Figures 5 and 6, in this embodiment, the control unit 1 has two power circuits 42A, 42B (hereinafter also referred to as the first power circuit 42A and the second power circuit 42B). Although not shown, the plurality of windings 24a also has two winding systems (hereinafter also referred to as the first plurality of windings and the second plurality of windings). The first power circuit 42A supplies current to the first plurality of windings to drive the motor 2. The second power circuit 42B supplies current to the second plurality of windings to drive the motor 2. By configuring the two power circuits 42A, 42B to be able to drive the motor 2 independently of each other, system redundancy is ensured.

[0056] The substrate 4 is formed with a plurality of first motor connection holes 45A connected to a plurality of motor terminal portions 28 extending from the first plurality of windings, and a plurality of second motor connection holes 45B connected to a plurality of motor terminal portions 28 extending from the second plurality of windings. The plurality of first motor connection holes 45A are arranged at positions corresponding to the plurality of motor terminal portions 28 extending from the first plurality of windings. The plurality of second motor connection holes 45B are arranged at positions corresponding to the plurality of motor terminal portions 28 extending from the second plurality of windings. For example, the plurality of first motor connection holes 45A are arranged at one end of the substrate 4 in the second orthogonal direction Y. The plurality of second motor connection holes 45B are arranged at the other end of the substrate 4 in the second orthogonal direction Y.

[0057] The substrate 4 has a control circuit mounting region R1 where the control circuit 41 is mounted, a first power circuit mounting region R21 where the first power circuit 42A is mounted, a second power circuit mounting region R22 where the second power circuit 42B is mounted, and a filter circuit region R3 where the filter circuit 43 is mounted.

[0058] Each of the power circuits 42A and 42B has a configuration similar to that of the power circuit 42 described in the first embodiment. Specifically, each of the power circuits 42A and 42B includes electronic components such as a switching element 42a, a shunt resistor 42b, a capacitor 42c, and a choke coil (not shown), as well as a wiring pattern 42d connecting these electronic components. The wiring pattern 42d of the first power circuit 42A is also connected to the first motor connection hole 45A, and the wiring pattern 42d of the second power circuit 42B is also connected to the second motor connection hole 45B. The switching elements 42a of the power circuits 42A and 42B are disposed on the second surface 4b of the substrate 4. The shunt resistors 42b and capacitors 42c of the power circuits 42A and 42B are disposed on the first surface 4a of the substrate 4.

[0059] In a plan view, the first power circuit 42A is disposed around the rotation sensor 47. That is, the first power circuit mounting region R21 is disposed around the rotation sensor 47. A portion of the first power circuit 42A is disposed between the rotation sensor 47 and the first motor connection hole 45A. The switching element 42a of the first power circuit 42A is disposed near the first motor connection hole 45A.

[0060] In a plan view, the second power circuit 42B is disposed around the rotation sensor 47. That is, the second power circuit mounting region R22 is disposed around the rotation sensor 47. A portion of the second power circuit 42B is disposed between the rotation sensor 47 and the second motor connection hole 45B. The switching element 42a of the second power circuit 42B is disposed near the second motor connection hole 45B.

[0061] The first power circuit 42A and the first motor connection hole 45A are disposed on one side of the rotation sensor 47 in the second orthogonal direction Y, and the second power circuit 42B and the second motor connection hole 45B are disposed on the other side of the rotation sensor 47 in the second orthogonal direction Y. In a plan view, the first power circuit 42A and the second power circuit 42B are disposed symmetrically with respect to a reference line L1 that passes through the central axis O and extends in the first orthogonal direction X. This arrangement prevents differences in electrical characteristics between the first power circuit 42A and the second power circuit 42B, eliminates the need for additional components to compensate for the differences in electrical characteristics, and improves the mounting efficiency of the board 4. Note that the arrangement of the first power circuit 42A, the first motor connection hole 45A, the second power circuit 42B, and the second motor connection hole 45B is not limited to this.

[0062] The housing 6 is formed with a plurality of first motor terminal through holes 65A through which the plurality of motor terminal portions 28 extending from the first plurality of windings are inserted, and a plurality of second motor terminal through holes 65B through which the plurality of motor terminal portions 28 extending from the second plurality of windings are inserted. The plurality of first motor terminal through holes 65A are arranged at one end of the housing 6 in the second orthogonal direction Y. The plurality of second motor terminal through holes 65B are arranged at the other end of the housing 6 in the second orthogonal direction Y. The plurality of first motor terminal through holes 65A and the plurality of second motor terminal through holes 65B are arranged on either side of the shaft through hole 61.

[0063] In this embodiment, the switching element 42 a and the shunt resistor 42 b of the first power circuit 42 A and the switching element 42 a and the shunt resistor 42 b of the second power circuit 42 B are heat-generating parts that generate heat when a current flows through them. The heat-generating parts may also include the wiring patterns 42 d of the power circuits 42 A and 42 B, the CPU 41 a and the IC 41 b of the control circuit 41, etc.

[0064] The housing 6 is disposed at a position overlapping the heat-generating portion in the axial direction Z and has a heat-transfer surface for transferring heat generated by the heat-generating portion to the housing 6. In the present embodiment, the heat-transfer surface includes a surface 63a1 of the flat portion 63a provided in a portion overlapping the switching elements 42a of the power circuits 42A, 42B in the axial direction Z, and a surface 63b1 of the recessed portion 63b provided in a portion overlapping the shunt resistors 42b of the power circuits 42A, 42B in the axial direction Z. Note that if the heat-generating portion includes the wiring patterns 42d of the power circuits 42A, 42B, the heat-transfer surface may include a portion of the opposing surface 6a overlapping the wiring patterns 42d of the power circuits 42A, 42B in the axial direction Z. If the heat-generating portion includes a CPU 41a or an IC 41b, the heat-transfer surface may include a surface 63c1 of the protruding portion 63c.

[0065] In this embodiment as well, the heat transfer surface is positioned so as to overlap the case mounting portion 62 and its vicinity in the axial direction Z. Most of the heat transfer surface is positioned so as to overlap the case mounting portion 62 in the axial direction Z. That is, in a plan view, most of the heat transfer surface is positioned between the shaft through hole 61 and the outer peripheral surface of the case mounting portion 62. Here, most of the heat transfer surface means, for example, 70% or more of the entire heat transfer surface. By arranging the heat transfer surface as described above, heat generated in the heat-generating portion can be more efficiently transferred to the motor case 3. Note that part of the heat transfer surface may be positioned near the motor terminal through holes 65A, 65B.

[0066] As described above, in the rotating electric machine 100 according to this embodiment, the winding 24a includes a first winding and a second winding. The sensor rotor 25 is attached to the rotating shaft 21, and the rotation sensor 47 is mounted on the substrate 4 so as to face the sensor rotor 25 in the axial direction Z. The substrate 4 is formed with a first motor connection hole 45A connected to the motor terminal 28 extending from the first winding and a second motor connection hole 45B connected to the motor terminal 28 extending from the second winding. The substrate 4 is also mounted with a first power circuit 42A including a shunt resistor 42b and a switching element 42a as a heat-generating portion and supplying current to the first winding, and a second power circuit 42B including a shunt resistor 42b and a switching element 42a as a heat-generating portion and supplying current to the second winding. When viewed from the axial direction Z, the first power circuit 42A and the first motor connection hole 45A are disposed on one side of the reference line L1, and the second power circuit 42B and the second motor connection hole 45B are disposed on the other side of the reference line L1. When viewed from the axial direction Z, at least a portion of the first power circuit 42A is disposed between the first motor connection hole 45A and the rotation sensor 47, and at least a portion of the second power circuit 42B is disposed between the second motor connection hole 45B and the rotation sensor 47. Providing two power circuits 42A and 42B ensures system redundancy. Furthermore, because two power circuits 42A and 42B are used to supply current to the winding 24a, the current supplied by each power circuit can be reduced, thereby reducing the amount of heat generated by each power circuit. Furthermore, when viewed from the axial direction Z, the first power circuit 42A and the first motor connection hole 45A are disposed on one side of the reference line L1, and the second power circuit 42B and the second motor connection hole 45B are disposed on the other side of the reference line L1, so that the heat-generating parts are dispersed and the heat transfer surfaces are also dispersed. This makes it possible to suppress localized heat generation caused by the heat-generating parts being concentrated, and also enables the heat generated by the heat-generating parts to be transferred to the housing 6 more efficiently.

[0067] Third Embodiment Next, a rotating electric machine according to a third embodiment will be described. The rotating electric machine according to this embodiment has the same basic configuration as the rotating electric machine according to the first embodiment, and therefore the following description will focus on the differences.

[0068] 7, in this embodiment, the power connection terminals 5 a and the signal connection terminals 5 b are press-fit terminals that are press-fit into the power connection holes 44 a and the signal connection holes 44 b, thereby contacting and electrically connecting with the conductive layers formed on the inner surfaces of the power connection holes 44 a and the signal connection holes 44 b.

[0069] As described above, in the rotating electric machine 100 according to this embodiment, the power connection terminals 5 a and the signal connection terminals 5 b are press-fit terminals. This allows the board 4 and the connector 5 to be easily electrically connected without soldering or the like, facilitating the assembly of the rotating electric machine 100. Furthermore, for example, if the power connection terminals 5 a and the signal connection terminals 5 b and the motor terminal 28 are both attached to the board 4 by soldering, if the extending direction of the power connection terminals 5 a and the signal connection terminals 5 b differs from the extending direction of the motor terminal 28, the soldering of the power connection terminals 5 a and the signal connection terminals 5 b and the soldering of the motor terminal 28 must be performed from different directions, making the assembly process more complicated. Therefore, when the power connection terminals 5a and the signal connection terminals 5b and the motor terminal portion 28 are both attached to the board 4 by soldering, it is preferable to position the connector 5 so that the power connection terminals 5a and the signal connection terminals 5b and the motor terminal portion 28 extend in the same direction. However, in this embodiment, the power connection terminals 5a and the signal connection terminals 5b are attached to the board 4 by press-fitting, so that the power connection terminals 5a and the signal connection terminals 5b can be easily attached to the board 4 even if the extending direction of the power connection terminals 5a and the signal connection terminals 5b differs from the extending direction of the motor terminal portion 28.

[0070] Embodiment 4 Next, a rotating electric machine according to embodiment 4 will be described. The rotating electric machine according to this embodiment has the same basic configuration as the rotating electric machine according to embodiment 1, and therefore the following description will focus on the differences.

[0071] 8 , in this embodiment, the capacitor storage holes 64 penetrate the housing 6 in the axial direction Z. Even in this case, at least a portion of the capacitor 42c is stored in the capacitor storage holes 64. Therefore, it is possible to suppress an increase in the size of the rotating electric machine 100 due to the capacitor 42c protruding from the substrate 4. Furthermore, since the capacitor storage holes 64 are formed as through holes, the capacitor storage holes 64 are easy to form.

[0072] Embodiment 5 Next, a rotating electric machine according to embodiment 5 will be described. The rotating electric machine according to this embodiment has the same basic configuration as the rotating electric machine according to embodiment 4, and therefore the following description will focus on the differences.

[0073] 9, in this embodiment, a second heat dissipation material 67 is provided between the capacitor housing hole 64 and the capacitor 42c. The capacitor 42c is thermally connected to the capacitor housing hole 64 via the second heat dissipation material 67. The second heat dissipation material 67 may be the same as or different from the heat dissipation material 7 provided between the heat transfer surface and the heat generating portion.

[0074] As described above, in this embodiment, the second heat dissipation material 67 is provided between the capacitor housing hole 64 and the capacitor 42c, thermally connecting the capacitor housing hole 64 and the capacitor 42c. This allows heat generated in the capacitor 42c to be transferred to the capacitor housing hole 64 via the second heat dissipation material 67, thereby suppressing temperature increases in the capacitor 42c and reducing deterioration due to heat generated by the capacitor 42c. Generally, the type and number of capacitors used in a control unit are determined taking into account deterioration due to heat generated. For example, if it is expected that the degree of deterioration due to heat generated by the capacitors is high, capacitors with larger capacities (i.e., larger sizes) are selected or the number of capacitors is increased. In this embodiment, suppressing deterioration due to heat generated by the capacitors 42c prevents an increase in the size and number of the capacitors 42c, thereby reducing an increase in the size of the rotating electric machine 100.

[0075] The technical scope of the present disclosure is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present disclosure.

[0076] For example, while the configuration in which the housing 6 has the flat portion 63a, the convex portion 63c, and the concave portion 63b has been described, this is not limiting. For example, the flat portion 63a may not be formed on the housing 6, and a convex portion protruding from the opposing surface 6a may be provided on the portion of the housing 6 that overlaps with the switching element 42a in the axial direction Z. The concave portion 63b may not be formed on the housing 6, and the portion of the housing 6 that overlaps with the shunt resistor 42b in the axial direction Z may be flush with the opposing surface 6a. That is, all heat transfer surfaces may be flush with the opposing surface 6a of the housing 6, all heat transfer surfaces may be formed on the surfaces of the convex portions protruding from the opposing surface 6a that face the substrate 4, all heat transfer surfaces may be formed on the surfaces of the concave portions recessed from the opposing surface 6a that face the substrate 4, or the heat transfer surfaces may be a combination of these. Furthermore, the heat dissipation material 7 may be disposed in a portion other than between the heat-generating portion and the heat transfer surface. Furthermore, heat transfer surfaces may not be provided on portions of the heat-generating portion that do not require heat transfer to the housing 6 (such as electronic components or wiring patterns).

[0077] Furthermore, the shunt resistor 42b, the CPU 41a, the IC 41b, or the like may be disposed on the second surface 4b of the substrate 4. In this case, heat generated by the shunt resistor 42b, the CPU 41a, or the IC 41b is transferred to the heat transfer surface via the substrate 4 and the heat dissipation material 7. Furthermore, in this case, the housing 6 may be formed with a protrusion that is provided at a position overlapping with the shunt resistor 42b, the CPU 41a, or the IC 41b in the axial direction Z and protrudes from the opposing surface 6a of the housing 6.

[0078] Furthermore, if the control circuit 41 includes a capacitor, the housing 6 may be provided with a capacitor storage hole for storing the capacitor of the control circuit 41 .

[0079] Furthermore, a second heat dissipation material 67 may be provided between the capacitor housing hole 64 having the bottom portion 64a in the first embodiment and the capacitor 42c.

[0080] Although the switching element 42a and shunt resistor 42b of the power circuit 42 and the CPU 41a and IC 41b of the control circuit 41 are illustrated as examples of heat-generating components, the heat-generating components are not limited to these. For example, if a motor relay element and a power supply relay element are mounted on the power circuit 42, these electronic components may be included in the heat-generating components. On the circuit board 4, the motor relay element may be disposed between the switching element 42a and the motor connection hole 45 (in the second embodiment, between the switching element 42a and the first motor connection hole 45A or the second motor connection hole 45B), and the power supply relay element may be disposed between the multiple power connection holes 44a and the capacitor 42c. Furthermore, if the filter electronic component 43a of the filter circuit 43 includes a filter coil, the filter coil may be included in the heat-generating components.

[0081] In addition, the above-described embodiments and modifications may be combined as appropriate.

[0082] DESCRIPTION OF SYMBOLS 1...Control unit 2...Motor 3...Motor case 4...Circuit board 4a...First surface 4b...Second surface 5...Connector 5a...Power connection terminal 5b...Signal connection terminal 6...Housing 6a...Opposite surface 7...Heat dissipation material 21...Rotating shaft 22...Rotor 23...Stator 24a...Winding 25...Sensor rotor 28...Motor terminal section 41...Control circuit 41a...CPU 41b...IC 42, 42A, 42B...Power circuit 42a...Switching element 42b...Shunt resistor 42c...Capacitor 44a...Power connection hole 44b...Signal connection hole 45, 45A, 45B...Motor connection hole 47...Rotation sensor 60...Main body section 61...Shaft through hole 62...Case mounting section 63a...Flat surface 63a1...Surface (heat transfer surface) 63b...Recess 63b1... surface (heat transfer surface) 64... capacitor storage hole 64a... bottom 67... second heat dissipation material 100... rotating electrical machine L1... reference straight line O... central axis X... first orthogonal direction (orthogonal direction) Y... second orthogonal direction Z... axial direction

Claims

1. a motor including a rotating shaft, a rotor fixed to the rotating shaft, a stator disposed on the outside of the rotor, a winding wound around the stator, and a motor case accommodating the rotating shaft, the rotor, and the stator; a control unit for controlling the motor; a housing disposed between the stator and the control unit in an axial direction along the rotation shaft, the housing having a shaft through-hole through which the rotation shaft is inserted; Equipped with the control unit has a substrate on which a heat generating portion is mounted, the housing has a main body portion and a case attachment portion that protrudes from the main body portion toward the stator and is attached to the motor case, the housing has a heat transfer surface facing the substrate and positioned to overlap the heat generating portion in the axial direction; a heat dissipation material is provided between the heat transfer surface and the heat generating portion, the heat dissipation material thermally connecting the heat transfer surface and the heat generating portion; At least a portion of the heat transfer surface is disposed at a position overlapping with the case mounting portion in the axial direction, a sensor rotor is attached to the rotating shaft, and a rotation sensor is mounted on the substrate so as to face the sensor rotor in the axial direction; a motor connection hole is formed in the substrate to be connected to a motor terminal portion extending from the winding; a power circuit including a capacitor, a shunt resistor as the heat generating portion, and a switching element is mounted on the substrate; When viewed from the axial direction, at least a portion of the power circuit is disposed between the motor connection hole and the rotation sensor, and is disposed closer to the motor connection hole than the rotation sensor. Rotating electric motor.

2. the control unit has a connector having a power connection terminal to which power is input from an external device and a signal connection terminal to which a signal is input from an external device, power connection holes connected to the power connection terminals and signal connection holes connected to the signal connection terminals are formed on the substrate, and a control circuit for controlling the power circuit is mounted on the substrate; When viewed from the axial direction, the control circuit is disposed between the signal connection hole and the power circuit. The rotating electric machine according to claim 1 .

3. the winding includes a first winding and a second winding; the substrate is formed with a first motor connection hole connected to a motor terminal portion extending from the first winding and a second motor connection hole connected to a motor terminal portion extending from the second winding; a first power circuit that supplies a current to the first winding and a second power circuit that supplies a current to the second winding are mounted on the substrate; the power circuit includes the first power circuit and a second power circuit; the first power circuit and the second power circuit each include a capacitor, a shunt resistor as the heat generating portion, and a switching element; when viewed from the axial direction, the first power circuit and the first motor connection hole are disposed on one side of a reference line that passes through a central axis of the rotating shaft and extends in a direction perpendicular to the axial direction, and the second power circuit and the second motor connection hole are disposed on the other side of the reference line; when viewed from the axial direction, at least a portion of the first power circuit is disposed between the first motor connection hole and the rotation sensor, and is disposed closer to the first motor connection hole than the rotation sensor; At least a portion of the second power circuit is disposed between the second motor connection hole and the rotation sensor, and is disposed closer to the second motor connection hole than the rotation sensor. The rotating electric machine according to claim 1 .

4. the control unit has a connector having a power connection terminal to which power is input from an external device and a signal connection terminal to which a signal is input from an external device, the substrate is formed with power connection holes connected to the power connection terminals and signal connection holes connected to the signal connection terminals, and is also mounted with a control circuit that controls the first power circuit and the second power circuit; When viewed from the axial direction, the control circuit is disposed between the signal connection hole and the first power circuit and the second power circuit. The rotating electric machine according to claim 3 .

5. the substrate has a first surface facing the housing and a second surface opposite the first surface; the capacitor and the shunt resistor are disposed on the first surface, and the switching element is disposed on the second surface; The housing has a capacitor storage hole that is arranged at a position overlapping the case mounting portion in the axial direction and that stores at least a portion of the capacitor. The rotating electric machine according to claim 1 or 2.

6. the housing is provided with a recessed portion that is provided at a position overlapping with the shunt resistor in the axial direction and recessed from a surface of the housing that faces the substrate, a surface of the recess facing the substrate is included in the heat transfer surface; The rotating electric machine according to claim 1 or 2.

7. the housing is provided with a protrusion that is provided at a position overlapping with the switching element in the axial direction and that protrudes from a surface of the housing that faces the board, a surface of the protrusion facing the substrate is included in the heat transfer surface; The rotating electric machine according to claim 1 or 2.

8. the control unit has a connector having a power connection terminal to which power is input from an external device and a signal connection terminal to which a signal is input from an external device, The substrate is formed with power connection holes connected to the power connection terminals and signal connection holes connected to the signal connection terminals, The power connection terminal and the signal connection terminal are press-fit terminals. The rotating electric machine according to claim 1 or 2.

9. The capacitor storage hole has a bottom facing the substrate. The rotating electric machine according to claim 5 .

10. The capacitor storage hole penetrates the housing in the axial direction. The rotating electric machine according to claim 5 .

11. A second heat dissipation material is provided between the capacitor storage hole and the capacitor, thermally connecting the capacitor storage hole and the capacitor. The rotating electric machine according to claim 5 .