Electric drive unit and electric power steering unit

Abstract

To provide an electric driving device and an electric power steering device to reduce influence of prying force of swinging around an axis perpendicular to an insertion / removal direction of a connector.SOLUTION: An electric driving device includes a motor, an electronic control device including a circuit board, and a heat sink. A connector is inserted and removed in a radial direction of a shaft and provided on a side opposite to a load side of the heat sink. The connector also has a first recess portion on the load side. The heat sink has a mounting surface for mounting the connector and a protrusion portion for protruding from the mounting surface toward the connector and being fitted into the first recess portion.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present disclosure relates to an electric drive device and an electric power steering device that include an electronic control device that controls the rotation of a motor. [Background technology]

[0002] An electric power steering device that generates auxiliary steering torque using a motor is equipped with an electronic control device that controls the motor. For example, Patent Document 1 describes a drive device that allows electronic components to be densely mounted on a board. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-034204 [Patent Document 2] Japanese Patent Application Laid-Open No. 2017-092100 Summary of the Invention [Problem to be solved by the invention]

[0004] In the electric drive device of Patent Document 1, the motor, electronic control device, and connector are arranged in this order along the axial direction parallel to the motor shaft. In the electric drive device of Patent Document 1, the connector is inserted and removed in the axial direction, so the size increases in the axial direction.

[0005] In contrast, in the electric drive device of Patent Document 2, the insertion and removal direction into and from the connector is the radial direction of the motor shaft, which makes the electric drive device of Patent Document 2 smaller in axial size than the electric drive device of Patent Document 1.

[0006] In the electric drive device of Patent Document 2, the connector terminals are electrically connected to the circuit board. The connector has a protrusion on the outside, which abuts against the cover when the connector is pulled out. This suppresses the force on the connector terminals that accompanies the insertion / removal direction of the connector. Here, when the connector is inserted or removed, a twisting force is generated that swings around an axis perpendicular to the insertion / removal direction of the connector, in addition to the insertion / removal direction of the connector.

[0007] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide an electric drive device and an electric power steering device that reduce the effects of twisting forces that oscillate around an axis perpendicular to the insertion / removal direction of the connector. [Means for solving the problem]

[0008] In order to achieve the above-mentioned object, one embodiment of an electric drive device comprises: a motor including a shaft extending axially from a load side to an anti-load side, a motor rotor interlocking with the shaft, a motor stator having a stator core that rotates the motor rotor, and a housing that houses the motor rotor and the motor stator; an electronic control device including a magnet provided on the anti-load side of the shaft, a heat sink provided on the anti-load side of the motor, a circuit board arranged on the anti-load side of the heat sink, and a rotation angle sensor located on the axial extension of the magnet and attached to the circuit board; and a connector that is inserted and removed radially of the shaft and provided on the anti-load side of the heat sink, wherein the connector has a first recess on the load side, and the heat sink has a mounting surface on which the connector is placed and a protrusion that protrudes further on the anti-load side than the mounting surface and fits into the first recess.

[0009] This reduces the size of the motor in the axial direction parallel to the shaft, making the electric drive device smaller. When the connector is inserted or removed, a twisting force is generated, causing it to swing around an axis perpendicular to the insertion / removal direction. The twisting force is absorbed by the protrusions, suppressing the connector's swinging motion. As a result, stress on the connection between the circuit board and the connector is suppressed, improving the reliability of the electric drive device.

[0010] In a preferred embodiment, the heat sink has a second recess that surrounds the protrusion and is recessed toward the load side from the mounting surface, so that the corner of the connector remains in the second recess and is less likely to come into contact with the protrusion.

[0011] In a preferred embodiment, the heat sink has a third recess that accommodates the head of a first bolt that fastens the motor and is recessed toward the load side from the mounting surface, thereby fixing the heat sink to the motor so that it does not shift even when a force is applied to insert or remove the connector.

[0012] In a preferred embodiment, the connector is sandwiched between the heat sink and the circuit board, and the circuit board and the connector are fixed by a second bolt, so that the connector is fixed so as not to shift relative to the circuit board.

[0013] In a preferred embodiment, a third bolt is provided to fix the circuit board and the heat sink at a position adjacent to the second bolt, and the rotating base is fixed so as not to shift relative to the heat sink.

[0014] In a preferred embodiment, the heat sink further has a first surface on the anti-load side of the mounting surface and a second surface on the anti-load side of the first surface, the second surface facing the circuit board and serving as a heat dissipation surface for dissipating heat from the circuit board, and a part of the connector is inserted between a stepped surface between the first surface and the mounting surface and the protrusion. Since the twisting force is received by the protrusion and the stepped surface, oscillation of the connector is further suppressed.

[0015] In a preferred embodiment, the protrusion is a rectangular pillar, whereby each surface of the rectangular pillar applies a reaction force to the twisting force, thereby further suppressing the swinging of the connector.

[0016] In a preferred embodiment, the heat sink is made of a metal material and the connector is made of a resin material, so that the metal protrusion can support the connector even if it is small.

[0017] In a preferred embodiment, the first recess is provided midway between both ends of the connector in the radial direction of the shaft, thereby ensuring sufficient space for the conductors of the connector while minimizing the volume of the first recess.

[0018] In a preferred embodiment, the heat sink further includes a cover covering the non-load side of the circuit board, the heat sink including a base having the mounting surface and the protrusion, and the connector is sandwiched between the end of the cover and the base. This suppresses axial displacement of the connector. As a result, stress from the connector terminals to the circuit board is reduced, improving the reliability of the circuit board.

[0019] In a preferred embodiment, the end of the cover is disposed between the protrusion and the radially outer end of the base in the radial direction of the shaft, thereby suppressing axial displacement of the connector.

[0020] The connector has a plurality of ribs extending in the radial direction of the shaft, and the end of the lid is adjacent to the ribs, thereby stabilizing the position of the lid.

[0021] In a preferred embodiment, the electric power steering device includes an electric drive unit that generates an auxiliary steering torque, thereby reducing the size of the motor in the axial direction parallel to the shaft and in the radial direction of the shaft, thereby improving the degree of freedom in the arrangement of the electric power steering device. [Effects of the Invention]

[0022] According to the present disclosure, it is possible to provide an electric drive device and an electric power steering device that reduce the influence of twisting forces that swing around an axis perpendicular to the insertion / removal direction of the connector. [Brief explanation of the drawings]

[0023] [Figure 1]FIG. 1 is a perspective view that schematically shows a vehicle equipped with an electric power steering device according to the first embodiment. [Figure 2] FIG. 2 is a schematic diagram of the electric power steering device according to the first embodiment. [Figure 3] FIG. 3 is a cross-sectional view schematically showing a cross section of the motor according to the first embodiment. [Figure 4] FIG. 4 is a schematic diagram showing wiring of the motor according to the first embodiment. [Figure 5] FIG. 5 is a schematic diagram showing the relationship between the motor and the ECU according to the first embodiment. [Figure 6] FIG. 6 is a side view of the electric drive device according to the first embodiment. [Figure 7] FIG. 7 is a plan view of the electric drive device according to the first embodiment. [Figure 8] 8 is a cross-sectional view taken along the line VIII-VIII in FIG. [Figure 9] 9 is a cross-sectional view taken along the line IX-IX of FIG. [Figure 10] FIG. 10 is a cross-sectional view taken along the line XX in FIG. [Figure 11] 11 is a cross-sectional view taken along the line XII-XII in FIG. [Figure 12] FIG. 12 is a perspective view illustrating the electric drive device according to the first embodiment with the cover removed. [Figure 13] FIG. 13 is a plan view of FIG. [Figure 14] FIG. 14 is a perspective view illustrating the electric drive device according to the first embodiment with the cover and the circuit board removed. [Figure 15] FIG. 15 is a plan view of FIG. [Figure 16] 16 is a cross-sectional view showing another example of a cross section taken along the line IX-IX of FIG. 7 in the electric drive device according to the second embodiment. [Figure 17] FIG. 17 is a perspective view of the connector according to the second embodiment. [Figure 18]FIG. 18 is a schematic diagram of an electric power steering device according to the third embodiment. [Figure 19] FIG. 19 is a side view showing an example of the arrangement of ECUs according to the third embodiment. [Figure 20] FIG. 20 is a schematic diagram of an electric power steering device according to the fourth embodiment. [Figure 21] FIG. 21 is a schematic diagram of an electric power steering device according to the fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0024] Modes (embodiments) for carrying out the present disclosure will be described in detail with reference to the drawings. The present disclosure is not limited to the contents described in the following embodiments. Furthermore, the components described below include those that can be easily imagined by a person skilled in the art and those that are substantially identical. Furthermore, the components described below can be combined as appropriate.

[0025] (Embodiment 1) Fig. 1 is a perspective view that schematically shows a vehicle equipped with an electric power steering device according to embodiment 1. Fig. 2 is a schematic diagram of the electric power steering device according to embodiment 1. As shown in Fig. 1, a vehicle 101 is equipped with an electric power steering device 100. An overview of the electric power steering device 100 will be described with reference to Fig. 2.

[0026] The electric power steering device 100 includes, in the order in which a force applied by a driver (operator) is transmitted, a steering wheel 91, a steering shaft 92, a universal joint 96, an intermediate shaft 97, a universal joint 98, a first rack-and-pinion mechanism 99, and a tie rod 72. The electric power steering device 100 also includes a torque sensor 94 that detects the steering torque of the steering shaft 92, a motor 30, an electronic control unit (hereinafter referred to as an ECU (Electronic Control Unit)) 10 that controls the motor 30, a reduction gear 75, and a second rack-and-pinion mechanism 70. A vehicle speed sensor 82, a power supply device 83 (e.g., an on-board battery), and an ignition switch 84 are provided on the vehicle body. The vehicle speed sensor 82 detects the traveling speed of the vehicle 101. The vehicle speed sensor 82 outputs the detected vehicle speed signal SV to the ECU 10 via CAN (Controller Area Network) communication. The ECU 10 is supplied with power from a power supply device 83 when an ignition switch 84 is in the on state.

[0027] The electric drive device 1 includes a motor 30 and an ECU 10 fixed to the anti-load side of a shaft 31 of the motor 30. The electric drive device 1 may also include an adapter that connects the ECU 10 and the motor 30.

[0028] As shown in Fig. 2, the steering shaft 92 includes an input shaft 92A, an output shaft 92B, and a torsion bar 92C. One end of the input shaft 92A is connected to the steering wheel 91, and the other end is connected to the torsion bar 92C. One end of the output shaft 92B is connected to the torsion bar 92C, and the other end is connected to a universal joint 96. The torque sensor 94 detects the torsion of the torsion bar 92C to detect the steering torque applied to the steering shaft 92. The torque sensor 94 outputs a steering torque signal T corresponding to the detected steering torque to the ECU 10 via CAN communication. The steering shaft 92 rotates due to the steering force applied to the steering wheel 91.

[0029] The intermediate shaft 97 has an upper shaft 97A and a lower shaft 97B, and transmits the torque of the output shaft 92B. The upper shaft 97A is connected to the output shaft 92B via a universal joint 96. On the other hand, the lower shaft 97B is connected to a first pinion shaft 99A of a first rack and pinion mechanism 99 via a universal joint 98. The upper shaft 97A and the lower shaft 97B are connected, for example, by a spline.

[0030] The first rack and pinion mechanism 99 has a first pinion shaft 99A, a first pinion gear 99B, a rack shaft 99C, and a first rack 99D. One end of the first pinion shaft 99A is connected to the lower shaft 97B via a universal joint 98, and the other end is connected to the first pinion gear 99B. A first rack 99D formed on the rack shaft 99C meshes with the first pinion gear 99B. The rotational motion of the steering shaft 92 is transmitted to the first rack and pinion mechanism 99 via the intermediate shaft 97. This rotational motion is converted into linear motion of the rack shaft 99C by the first rack and pinion mechanism 99. The tie rods 72 are connected to both ends of the rack shaft 99C.

[0031] The motor 30 generates an auxiliary steering torque to assist the driver in steering, and may be a brushless motor or a brush motor having brushes and a commutator.

[0032] The ECU 10 includes a rotation angle sensor 23a. The rotation angle sensor 23a detects the rotation phase of the motor 30. The ECU 10 acquires a rotation phase signal of the motor 30 from the rotation angle sensor 23a, acquires a steering torque signal T from the torque sensor 94, and acquires a vehicle speed signal SV of the vehicle 101 from the vehicle speed sensor 82. The ECU 10 calculates an assist steering command value of the assist command based on the rotation phase signal, the steering torque signal T, and the vehicle speed signal SV. The ECU 10 supplies a current to the motor 30 based on the calculated assist steering command value.

[0033] The reduction gear 75 includes a worm shaft 75A that rotates integrally with the shaft 31 of the motor 30, and a worm wheel 75B that meshes with the worm shaft 75A. Therefore, the rotational motion of the shaft 31 is transmitted to the worm wheel 75B via the worm shaft 75A. In the first embodiment, the side of the shaft 31 that faces the reduction gear 75 is referred to as the load side end, and the side of the shaft 31 opposite the reduction gear 75 is referred to as the anti-load side end.

[0034] The second rack and pinion mechanism 70 has a second pinion shaft 71A, a second pinion gear 71B, and a second rack 71C. One end of the second pinion shaft 71A is fixed coaxially with the worm wheel 75B and rotates integrally therewith. The other end of the second pinion shaft 71A is connected to the second pinion gear 71B. The second rack 71C formed on the rack shaft 99C meshes with the second pinion gear 71B. The rotational motion of the motor 30 is transmitted to the second rack and pinion mechanism 70 via the reduction gear 75. This rotational motion is converted into linear motion of the rack shaft 99C by the second rack and pinion mechanism 70.

[0035] The driver's steering force input to the steering wheel 91 is transmitted to the first rack and pinion mechanism 99 via the steering shaft 92 and the intermediate shaft 97. The first rack and pinion mechanism 99 transmits the transmitted steering force to the rack shaft 99C as a force applied in the axial direction of the rack shaft 99C. At this time, the ECU 10 acquires the steering torque signal T input to the steering shaft 92 from the torque sensor 94. The ECU 10 acquires the vehicle speed signal SV from the vehicle speed sensor 82. The ECU 10 acquires the rotation phase signal of the motor 30 from the rotation angle sensor 23a. The ECU 10 then outputs a control signal to control the operation of the motor 30. The assistive steering torque generated by the motor 30 is transmitted to the second rack and pinion mechanism 70 via the reduction gear 75. The second rack and pinion mechanism 70 transmits the assistive steering torque to the rack shaft 99C as a force applied in the axial direction of the rack shaft 99C. In this way, the electric power steering device 100 assists the driver in steering the steering wheel 91.

[0036] 2, the electric power steering device 100 is of a rack assist type in which an assist force is applied to the second rack and pinion mechanism 70, but is not limited to this. The electric power steering device 100 may be of a column assist type in which an assist force is applied to the steering shaft 92, or a pinion assist type in which an assist force is applied to the first pinion gear 99B, for example.

[0037] FIG. 3 is a cross-sectional view schematically illustrating a cross section of the motor according to the first embodiment. FIG. 4 is a schematic diagram illustrating wiring of the motor according to the first embodiment. In the first embodiment, the circumferential direction is a direction along a concentric circle centered on the shaft 31. The radial direction is a direction away from the shaft 31 in a plane perpendicular to the axial direction Ax. As shown in FIG. 3, the motor 30 includes a housing 930, a motor stator having a stator core 931, and a motor rotor 932. The motor stator includes the cylindrical stator core 931, a plurality of first coils 37, and a plurality of second coils 38. The stator core 931 includes an annular back yoke 931a and a plurality of teeth 931b protruding from the inner circumferential surface of the back yoke 931a. Twelve teeth 931b are arranged in the circumferential direction. The motor rotor 932 includes a rotor yoke 932a and a magnet 932b. The magnets 932b are provided on the outer peripheral surface of the rotor yoke 932a. The number of magnets 932b is, for example, 8. The rotation of the motor rotor 932 is linked to the rotation of the shaft 31.

[0038] As shown in FIG. 3, the first coils 37 are wound in a concentrated manner around each of the teeth 931b. The first coils 37 are wound in a concentrated manner around the outer periphery of the teeth 931b with an insulator interposed therebetween. All of the first coils 37 are included in a first coil system. The first coil system according to the first embodiment is supplied with current and excited by an inverter circuit 251 (see FIG. 5) included in the first power circuit 25A. The first coil system includes, for example, six first coils 37. The six first coils 37 are arranged so that two first coils 37 are adjacent to each other in the circumferential direction. Three first coil groups Gr1, each consisting of adjacent first coils 37, are arranged at equal intervals in the circumferential direction. That is, the first coil system includes three first coil groups Gr1 arranged at equal intervals in the circumferential direction. The number of first coil groups Gr1 does not necessarily have to be three; it is sufficient that 3n first coil groups Gr1 are arranged at equal intervals in the circumferential direction, where n is a natural number. It is also preferable that n is an odd number. As described above, in the first embodiment, there are a plurality of coil groups, which are divided into at least two systems, the first coil group gr1 and the second coil group Gr2, for each of the three phases, and the stator core is excited by three-phase AC.

[0039] As shown in FIG. 3, the second coil 38 is concentratedly wound around each of the multiple teeth 931b. The second coil 38 is concentratedly wound around the outer periphery of the tooth 931b with an insulator interposed therebetween. The teeth 931b around which the second coil 38 is concentratedly wound are different from the teeth 931b around which the first coil 37 is concentratedly wound. All of the second coils 38 are included in a second coil system. The second coil system is supplied with current and excited by an inverter circuit 251 (see FIG. 5) included in the second power circuit 25B. The second coil system includes, for example, six second coils 38. The six second coils 38 are arranged so that two second coils 38 are adjacent to each other in the circumferential direction. Three second coil groups Gr2, each consisting of adjacent second coils 38, are arranged at equal intervals in the circumferential direction. That is, the second coil system includes three second coil groups Gr2 arranged at equal intervals in the circumferential direction. The number of second coil groups Gr2 does not necessarily have to be three, but may be 3n, where n is a natural number, and it is preferable that n is an odd number.

[0040] 4, the six first coils 37 include two first U-phase coils 37Ua and 37Ub excited by a first U-phase current I1u, two first V-phase coils 37Va and 37Vb excited by a first V-phase current I1v, and two first W-phase coils 37Wa and 37Wb excited by a first W-phase current I1w. 1U-phase coil 37Ub is connected in series to 1U-phase coil 37Ua. 1V-phase coil 37Vb is connected in series to 1V-phase coil 37Va. 1W-phase coil 37Wb is connected in series to 1W-phase coil 37Wa. All of the first coils 37 are wound in the same direction around teeth 931b. Furthermore, first U-phase coil 37Ub, first V-phase coil 37Vb, and first W-phase coil 37Wb are joined together in a star connection (Y connection).

[0041] 4, the six second coils 38 include two second U-phase coils 38Ua and 38Ub excited by a second U-phase current I2u, two second V-phase coils 38Va and 38Vb excited by a second V-phase current I2v, and two second W-phase coils 38Wa and 38Wb excited by a second W-phase current I2w. 2U-phase coil 38Ub is connected in series to 2U-phase coil 38Ua. 2V-phase coil 38Vb is connected in series to 2V-phase coil 38Va. 2W-phase coil 38Wb is connected in series to 2W-phase coil 38Wa. The winding directions of all second coils 38 about teeth 931b are the same as the winding direction of first coil 37. Furthermore, the second U-phase coil 38Ub, the second V-phase coil 38Vb, and the second W-phase coil 38Wb are joined together in a star connection (Y connection).

[0042] 3, the three first coil groups Gr1 are comprised of a first UV coil group Gr1UV, a first VW coil group Gr1VW, and a first UW coil group Gr1UW. The first UV coil group Gr1UV includes a first U-phase coil 37Ub and a first V-phase coil 37Va that are adjacent to each other in the circumferential direction. The first VW coil group Gr1VW includes a first V-phase coil 37Vb and a first W-phase coil 37Wa that are adjacent to each other in the circumferential direction. The first UW coil group Gr1UW includes a first U-phase coil 37Ua and a first W-phase coil 37Wb that are adjacent to each other in the circumferential direction.

[0043] 3, the three second coil groups Gr2 are composed of a second UV coil group Gr2UV, a second VW coil group Gr2VW, and a second UW coil group Gr2UW. The second UV coil group Gr2UV includes a second U-phase coil 38Ub and a second V-phase coil 38Va that are adjacent to each other in the circumferential direction. The second VW coil group Gr2VW includes a second V-phase coil 38Vb and a second W-phase coil 38Wa that are adjacent to each other in the circumferential direction. The second UW coil group Gr2UW includes a second U-phase coil 38Ua and a second W-phase coil 38Wb that are adjacent to each other in the circumferential direction.

[0044] First coil 37, which is excited by first U-phase current I1u, faces second coil 38, which is excited by second U-phase current I2u, in the radial direction of stator core 931. In the following description, the radial direction of stator core 931 will be simply referred to as the radial direction. For example, as shown in FIG. 3, first U-phase coil 37Ua faces second U-phase coil 38Ua, and first U-phase coil 37Ub faces second U-phase coil 38Ub in the radial direction.

[0045] First coil 37, excited by first V-phase current I1v, faces, in the radial direction, second coil 38, excited by second V-phase current I2v. For example, as shown in Fig. 3, first V-phase coil 37Va faces, in the radial direction, second V-phase coil 38Va, and first V-phase coil 37Vb faces, in the radial direction, second V-phase coil 38Vb.

[0046] First coil 37, which is excited by first W-phase current I1w, faces, in the radial direction, second coil 38, which is excited by second W-phase current I2w. For example, as shown in Fig. 3, first W-phase coil 37Wa faces, in the radial direction, second W-phase coil 38Wa, and first W-phase coil 37Wb faces, in the radial direction, second W-phase coil 38Wb.

[0047] FIG. 5 is a schematic diagram showing the relationship between the motor and the ECU according to the first embodiment. As shown in FIG. 5, the ECU 10 includes a detection circuit 23, a control circuit 24, a first power circuit 25A, and a second power circuit 25B. The detection circuit 23 includes a rotation angle sensor 23a and a motor rotation speed calculation unit 23b. The control circuit 24 includes a control calculation unit 241, a gate drive circuit 242, and a cutoff drive circuit 243. The first power circuit 25A includes an inverter circuit 251 and a current cutoff circuit 255. The second power circuit 25B includes the inverter circuit 251 and the current cutoff circuit 255. The inverter circuit 251 also includes a plurality of switching elements 252 and a current detection circuit 254 for detecting a current value. Note that circuits that do not require description are omitted in FIG. 5 as appropriate.

[0048] Control calculation unit 241 calculates a motor current command value. Motor rotation speed calculation unit 23b calculates a motor electrical angle θm and outputs it to control calculation unit 241. Gate drive circuit 242 receives the motor current command value output from control calculation unit 241. Gate drive circuit 242 controls first power circuit 25A and second power circuit 25B based on the motor current command value.

[0049] 5, the ECU 10 includes a rotation angle sensor 23a. The rotation angle sensor 23a is, for example, a magnetic sensor. A detection value of the rotation angle sensor 23a is supplied to a motor rotation speed calculation unit 23b. The motor rotation speed calculation unit 23b calculates a motor electrical angle θm based on the detection value of the rotation angle sensor 23a, and outputs the calculated value to a control calculation unit 241.

[0050] The control calculation unit 241 receives as input the steering torque signal T detected by the torque sensor 94, the vehicle speed signal SV detected by the vehicle speed sensor 82, and the motor electrical angle θm output from the motor rotation speed calculation unit 23b. The control calculation unit 241 calculates a motor current command value based on the steering torque signal T, the vehicle speed signal SV, and the motor electrical angle θm, and outputs the motor current command value to the gate drive circuit 242.

[0051] Gate drive circuit 242 calculates a first pulse width modulation signal based on the motor current command value and outputs it to inverter circuit 251 of first power circuit 25A. Inverter circuit 251 switches switching elements 252 to obtain three-phase current values ​​according to the duty ratio of the first pulse width modulation signal, thereby generating a three-phase AC current including a first U-phase current I1u, a first V-phase current I1v, and a first W-phase current I1w. The first U-phase current I1u excites first U-phase coil 37Ua and first U-phase coil 37Ub, the first V-phase current I1v excites first V-phase coil 37Va and first V-phase coil 37Vb, and the first W-phase current I1w excites first W-phase coil 37Wa and first W-phase coil 37Wb.

[0052] Gate drive circuit 242 calculates a second pulse-width modulated signal based on the motor current command value and outputs it to inverter circuit 251 of second power circuit 25B. Inverter circuit 251 switches switching elements 252 to obtain three-phase current values ​​according to the duty ratio of the second pulse-width modulated signal, thereby generating a three-phase AC current including a second U-phase current I2u, a second V-phase current I2v, and a second W-phase current I2w. The second U-phase current I2u excites second U-phase coil 38Ua and second U-phase coil 38Ub, the second V-phase current I2v excites second V-phase coil 38Va and second V-phase coil 38Vb, and the second W-phase current I2w excites second W-phase coil 38Wa and second W-phase coil 38Wb.

[0053] The inverter circuit 251 is a power conversion circuit that converts DC power into AC power. As described above, the inverter circuit 251 has a plurality of switching elements 252. The switching elements 252 are, for example, field effect transistors. A smoothing capacitor 253 is connected in parallel to the inverter circuit 251. The smoothing capacitor 253 is, for example, an electrolytic capacitor. The circuit board 20 includes a plurality of smoothing capacitors connected in parallel as the smoothing capacitor 253.

[0054] As described above, the inverter circuit 251 also includes a current detection circuit 254. The current detection circuit 254 includes, for example, a shunt resistor. The current value detected by the current detection circuit 254 is sent to the control calculation unit 241. The current detection circuit 254 may be connected to detect the current value of each phase of the motor 30.

[0055] The current interruption circuit 255 is disposed between the inverter circuit 251 and the first coil 37 or the second coil 38. When the current value detected by the current detection circuit 254 is determined to be abnormal, the control calculation unit 241 drives the current interruption circuit 255 via the interruption drive circuit 243 to interrupt the current flowing from the inverter circuit 251 to the first coil 37. The control calculation unit 241 also drives the current interruption circuit 255 via the interruption drive circuit 243 to interrupt the current flowing from the inverter circuit 251 to the second coil 38. In this way, the current flowing to the first coil 37 and the current flowing to the second coil 38 are independently controlled by the control calculation unit 241. Input / output signals such as a steering torque signal T and a vehicle speed signal SV are transmitted to the control calculation unit 241 via a connector CNT.

[0056] FIG. 6 is a side view of the electric drive device according to the first embodiment. FIG. 7 is a plan view of the electric drive device according to the first embodiment. FIG. 8 is a cross-sectional view taken along the line VIII-VIII in FIG. 6. FIG. 9 is a cross-sectional view taken along the line IX-IX in FIG. 7. FIG. 10 is a cross-sectional view taken along the line XI-XI in FIG. 7. FIG. 11 is a cross-sectional view taken along the line XII-XII in FIG. 6. FIG. 12 is a perspective view of the electric drive device according to the first embodiment with the cover removed. FIG. 13 is a plan view of FIG. 12. FIG. 14 is a perspective view of the electric drive device according to the first embodiment with the cover and the circuit board removed. FIG. 15 is a plan view of FIG. 14. As shown in FIGS. 6 and 7, the electric drive device 1 includes a motor 30 and an ECU 10 disposed on the anti-load side of the motor 30.

[0057] As shown in FIGS. 6 and 7, the ECU 10 includes a heat sink 40 and a lid 50 that covers the anti-load side of the heat sink 40. As shown in FIG. 8, the heat sink 40 supports the circuit board 20, and the lid 50 covers the circuit board 20. As shown in FIG. 9, the circuit board 20 and a connector CNT are attached to the heat sink 40. When viewed from the axial direction Ax, the connector CNT is arranged in a direction F1 that allows a connector terminal of a wire harness to be inserted and removed from the radial outside of the shaft 31 of the motor 30. As described above, the ECU 10 includes the circuit board 20, the heat sink 40 that supports the circuit board 20, the connector CNT, and the lid 50.

[0058] As shown in Figure 8, the motor 30 includes a housing 930. The motor rotor 932 includes a rotor yoke 932a and a magnet 932b. The magnet 932b is provided on the outer peripheral surface of the rotor yoke 932a. The housing 930 is cylindrical and accommodates therein the motor rotor 932, a stator including a plurality of coil groups divided into two systems for each three phase, for example, a first coil group Gr1 and a second coil group Gr2 (see Figure 3), and the shaft 31.

[0059] As shown in Fig. 8, the circuit board 20 has a board body 21 and a plurality of electronic components mounted on the board body 21. The board body 21 is, for example, a printed circuit board made of resin or the like. The plurality of electronic components mounted on one board body 21 include, for example, a central processing unit (CPU), an application specific integrated circuit (ASIC), a field effect transistor (FET), a magnetic sensor, an electrolytic capacitor, a resistive element, a diode, a thermistor, and the like. The plurality of electronic components configure the detection circuit 23, the control circuit 24, the first power circuit 25A, and the second power circuit 25B shown in Fig. 5.

[0060] 8 and 9, the heat sink 40 supports the circuit board 20. The circuit board 20 is fixed to one surface (anti-load side) of the heat sink 40. The heat sink 40 is made of a metal material with high heat dissipation properties, such as aluminum or copper, and efficiently dissipates heat generated by the circuit board 20 to the outside.

[0061] As shown in Figure 8, shaft 31 is rotatably supported by bearings 33 and 34. Bearing 33 is interposed between heat sink 40 and shaft 31. A bearing support portion 411 is provided on the load side of heat sink 40, and there is a hollow portion 45H in heat sink 40 through which shaft 31 passes. Bearing 33 is disposed inside 35 of hollow portion 45H surrounded by bearing support portion 411. Bearing 34 is interposed between housing 930 and shaft 31.

[0062] As shown in Figures 8 and 9, a magnet 32 ​​is attached to one end of the shaft 31 via a magnet holder 32A. Half of the magnet 32 ​​is magnetized as a south pole when viewed in the axial direction Ax, and the other half is magnetized as a north pole. Alternatively, the magnet 32 ​​may have south and north poles arranged alternately on its outer surface when viewed in the circumferential direction. Because the bearing 33 has high component precision, the position of the magnet 32, which is located on the anti-load side of the heat sink 40, in the axial direction Ax is constant. The end where the magnet 32 ​​is located is the anti-load side end of the shaft 31.

[0063] A motor gear 31G that transmits rotation to a worm shaft 75A (see FIG. 1) is provided at the other end of the shaft 31. The end where the motor gear 31G is provided is the end of the shaft 31 on the load side.

[0064] The substrate body 21 has a first surface 21b and a second surface 21a located on the opposite side of the first surface 21b. The detection circuit 23, the control circuit 24, the first power circuit 25A, and the second power circuit 25B shown in Fig. 5 are configured with one or more electronic components mounted on the first surface 21b or the second surface 21a. For example, the rotation angle sensor 23a is configured with one electronic component mounted on the first surface 21b of the substrate body 21.

[0065] 5 is configured with a plurality of electronic components mounted on the second surface 21a of the board body 21. The circuit board 20 also includes a smoothing capacitor 253 mounted on the second surface 21a of the board body 21.

[0066] The rotation angle sensor 23a is disposed on the anti-load side of the shaft 31, on an extension of the axial direction Ax of the magnet 32. The board body 21 has a plane perpendicular to the axial direction Ax as its mounting surface for the rotation angle sensor 23a. The rotation angle sensor 23a is mounted on the board body 21 so as to be able to sense changes in the magnetic field of the magnet 32. It is desirable that the magnet 32 ​​and the rotation angle sensor 23a face each other in the axial direction Ax. The rotation angle sensor 23a may be disposed on the second surface 21a instead of the first surface 21b of the board body 21, or on both the first surface 21b and the second surface 21a of the board body 21.

[0067] The rotation angle sensor 23a is, for example, a spin valve sensor. A spin valve sensor is an element in which a non-magnetic layer is sandwiched between a pinned layer of a ferromagnetic material, the magnetization direction of which is fixed by an antiferromagnetic layer or the like, and a free layer of a ferromagnetic material, and is a sensor that can detect changes in the direction of magnetic flux. Spin valve sensors include GMR (Giant Magneto Resistance) sensors and TMR (Tunnel Magneto Resistance) sensors. Note that the rotation angle sensor 23a may be any sensor that can detect the rotation of the magnet 32. The rotation angle sensor 23a may be, for example, an AMR (Anisotropic Magneto Resistance) sensor or a Hall sensor.

[0068] The lid 50 is made of metal or resin and prevents foreign matter and moisture from entering the inside of the electric drive device 1. As shown in Fig. 8, the lid 50 is fixed by being sandwiched between a support post 451 protruding on the anti-load side of the heat sink 40 and a bolt CT, which is a fixing member.

[0069] 9, 10, and 11, the heat sink 40 includes a pedestal 44 that supports the connector CNT. The pedestal 44 protrudes radially outward beyond the inner wall of the housing 930. The connector CNT is disposed on the anti-load side of the pedestal 44.

[0070] The connector CNT has terminals CNTP of the connector CNT, including a power supply terminal, a communication terminal for performing CAN communication, and an input / output terminal for inputting and outputting data by a method other than CAN communication. The resin material of the connector CNT is, for example, polybutylene terephthalate (PBT). The terminals CNTP of the connector CNT are electrically connected to the circuit board 20.

[0071] As shown in FIGS. 12 and 13, the circuit board 20 is disposed on the anti-load side of the heat sink 40.

[0072] 14 and 15, the heat sink 40 has a step between a first surface 41 and a second surface 42 on the anti-load side of the heat sink body. The first surface 41 does not have to be flat as long as it is lower than the second surface 42 in the axial direction Ax. The mounting surface 441 is located closer to the load side than the first surface, and the second surface 42 is located closer to the anti-load side than the first surface.

[0073] As shown in FIG. 14, the heat sink 40 has support columns 451 and 452 that protrude from the first surface 41 toward the anti-load side. The support columns 451 and 452 each have a female thread that is threaded in the axial direction Ax from the top surface on the anti-load side. As shown in FIG. 12, the support column 451 protrudes beyond the circuit board 20. As shown in FIG. 8, the cover 50 is fixed to the heat sink 40 by fastening a bolt CT that passes through the cover 50 to the female thread of the support column 451.

[0074] 12, a bolt BT1 that passes through the circuit board 20 is fastened to the female thread of the support column 452. This fixes the circuit board 20 to the heat sink 40 so that it does not shift.

[0075] 12, the connector CNT is sandwiched between the heat sink 40 and the circuit board 20, and the circuit board 20 and the connector CNT are fixed with a bolt BT2. This fixes the connector CNT to the circuit board 20 so that it does not shift.

[0076] A bolt BT1 that fixes the heat sink 40 to the circuit board 20 is disposed at a position adjacent to the bolt BT2. Since the bolt BT1 (second bolt) and the bolt BT2 (third bolt) are close to each other, even if the connector CNT swings, the swing of the connector CNT can be suppressed by the fastening force of the bolt BT1 in addition to the fastening force of the bolt BT2.

[0077] 12, the electric drive device 1 includes a first coil wiring 321 that connects the first coil group Gr1 to the circuit board 20, and a second coil wiring 322 that connects the second coil group Gr2 to the circuit board 20. The first coil wiring 321 and the second coil wiring 322 may be included in the ECU 10 or the motor 30.

[0078] As shown in FIG. 12, first coil wiring 321 and second coil wiring 322 are inserted into the through holes of circuit board 20, and circuit board 20 and first coil wiring 321 and second coil wiring 322 are electrically connected to each other.

[0079] 12 and 13, the second surface 42 faces the circuit board 20 in order to dissipate heat generated by the circuit board 20. A heat dissipation material is applied between the circuit board 20 and the second surface 42 of the heat sink 40. The heat dissipation material is, for example, a material in which a thermally conductive filler is mixed with a silicone polymer, and is called a TIM (Thermal Interface Material). The heat dissipation material may be any material other than the above materials, as long as it has a higher thermal conductivity than the board body 21 of the circuit board 20.

[0080] As shown in Figures 11, 14 and 15, on the anti-load side of the base portion 44 there is a mounting surface 441 on which the connector CNT is mounted, a protrusion 442 that protrudes further toward the anti-load side than the mounting surface 441, a recess 443 at the base of the protrusion 442 that is recessed toward the load side than the mounting surface 441, and a recess 444 that is recessed toward the load side than the mounting surface 441 and accommodates the head of the bolt BBT, which is a fixing member.

[0081] 9 and 11, the connector CNT has a recess CNTR on the load side. A protrusion 442 is fitted into the recess CNTR. When viewed in the radial direction of the shaft 31, the recess CNTR is provided midway between both ends of the connector CNT. This allows the recess CNTR to have a minimum volume, ensuring sufficient conductor space for the connector.

[0082] 14, the shape of the protrusion 442 is a rectangular pillar. As a result, each surface of the rectangular pillar applies a reaction force to the twisting forces F2 and F3, further suppressing the swinging of the connector CNT. Because the protrusion 442 is made of metal, it can support the connector CNT even though it is small.

[0083] As shown in FIGS. 10 and 14, the bolts BBT that pass through the base portion 44 are fastened to the female threads of the flange 933 of the motor 30, thereby fixing the heat sink 40 to the motor 30.

[0084] As described above, the electric drive device 1 according to the first embodiment includes the motor 30, the ECU 10 provided on the anti-load side of the shaft 31 for driving and controlling the motor 30, and the connector CNT. The ECU 10 includes the magnet 32 ​​at the end of the shaft 31 on the anti-load side, and the circuit board 20 arranged on the anti-load side of the shaft 31, on an extension line in the axial direction of the shaft 31 (for example, the axial direction Ax). The circuit board 20 has a detection circuit 23 including a rotation angle sensor 23a that detects rotation of the magnet 32. The rotation angle sensor 23a is a magnetic sensor that detects rotation of the magnet 32.

[0085] The connector CNT is inserted and removed radially from the shaft 31, and is provided on the anti-load side of the heat sink 40. The connector CNT has a recess CNTR (first recess) on the load side. The heat sink 40 has a mounting surface 441 on which the connector CNT is placed, and a protrusion 442 that protrudes further toward the connector CNT than the mounting surface 441 and fits into the recess CNTR.

[0086] This reduces the size of the axial direction Ax parallel to the shaft 31 of the motor 30, making the electric drive device 1 smaller. When the connector CNT is inserted or removed, twisting forces F2 and F3 are generated, causing the connector CNT to swing about an axis perpendicular to the insertion or removal direction. The twisting forces F2 and F3 are received by the protrusion 442, so the swinging of the connector CNT is suppressed. As a result, stress applied to the connection between the circuit board 20 and the connector CNT is suppressed, improving the reliability of the electric drive device 1.

[0087] The heat sink 40 has a recess 443 (second recess) that surrounds the protrusion 442 and is recessed toward the load side from the mounting surface 441. This allows the corner CNTQ (see FIG. 11) of the connector to remain in the recess 443 and is less likely to come into contact with the protrusion 442.

[0088] The heat sink 40 has a recess 444 (third recess) that accommodates the head of a bolt BBT (first bolt) that fastens to the flange 933 of the motor 30 and is recessed toward the load side from the mounting surface 441. Because the protrusion 442 and the recess 444 are adjacent to each other, the heat sink 40 is fixed so as not to shift relative to the motor 30 even if an insertion / removal force is applied to the connector CNT.

[0089] The heat sink 40 further has a first surface 41 located on the anti-load side of the mounting surface 441, and a second surface located on the anti-load side of the first surface 41. The second surface faces the circuit board and is a heat dissipation surface that dissipates heat from the circuit board, and a part of the connector is inserted between the protrusion and a stepped surface between the first surface and the mounting surface. Since the twisting force is received by the protrusion and the stepped surface, the connector is further suppressed from swinging.

[0090] The electric power steering device 100 includes the electric drive device 1 described above, and the electric drive device 1 generates an auxiliary steering torque. This reduces the size of the axial direction Ax parallel to the shaft 31 of the motor 30 and the radial direction of the shaft 31, improving the degree of freedom in the arrangement of the electric power steering device 100.

[0091] (Embodiment 2) Fig. 16 is a cross-sectional view showing another example of a cross section taken along the line IX-IX in Fig. 7 in the electric drive device according to embodiment 2. Fig. 17 is a perspective view of a connector according to embodiment 2. Note that the same components as those described in embodiment 1 above are given the same reference numerals, and redundant description will be omitted. In embodiment 2, the base portion 44 protrudes radially outward more than in embodiment 1.

[0092] As shown in FIG. 16 , the connector CNT penetrates the circuit board 20 from the load side to the anti-load side and is joined by soldering or the like. The protrusion 442 reduces the twisting forces F2 and F3 applied to the connector CNT. Here, the circuit board 20 and the connector CNT are connected via the terminal CNTP of the connector CNT. Static force applied to the connector CNT via the harness may lead to displacement of the connector CNT with the protrusion 442 as a fulcrum. Furthermore, axial displacement of the connector CNT may be transmitted to the circuit board 20 via the terminal CNTP of the connector CNT. Stress applied to the circuit board 20 by the terminal CNTP of the connector CNT may lead to distortion of the circuit board 20, potentially damaging the reliability of the circuit board 20. Therefore, it is desirable to suppress the stress on the circuit board 20 due to the displacement of the connector CNT.

[0093] For this reason, in the electric drive device 1 of the second embodiment, position P2 of the lid body 50 that is closest to the connector CNT is located radially outward from position P1 of the radial center of the protrusion 442. The base 44 is made larger than in the first embodiment, and position P3 of the radial outer end of the pedestal 44 is located radially outward from position P2 of the lid body 50. As a result, the connector CNT, which is located radially outward from the recess CNTR that fits into the protrusion 442, is sandwiched between the lid body 50 and the base 44, thereby suppressing axial displacement of the connector CNT.

[0094] When viewed in the radial direction of the shaft 31, position P3 is disposed between positions P1 and P3, so that connector CNT is less likely to be displaced in the axial direction.

[0095] 17, the connector CNT is provided with a water blocking wall CNTW and a plurality of ribs CNTB extending radially outward from the water blocking wall CNTW at a position inside the lid body 50. For example, three ribs CNTB are spaced apart and axially face and are close to the end 50F of the lid body 50 at position P2 (see FIG. 16). The three ribs CNTB can reduce the distance to the end 50F of the lid body 50 and support the end 50F of the lid body 50 at multiple points, making it easier to stabilize the posture of the lid body 50.

[0096] The water blocking wall CNTW and the lid body 50 face each other in the radial direction of the shaft. The smaller the distance between the water blocking wall CNTW and the end 50F of the lid body 50, the more the displacement of the connector CNT can be suppressed. The distance between the water blocking wall CNTW and the end 50F of the lid body 50 is, for example, in the range of 0.1 mm or more and 0.3 mm or less. The water blocking wall CNTW is integrated with the lid body 50, suppressing the displacement of the connector CNT in the axial direction.

[0097] (Embodiment 3) Fig. 18 is a schematic diagram of an electric power steering device according to embodiment 3. Fig. 19 is a side view showing an example of the arrangement of an ECU according to embodiment 3. Note that the same components as those described in the above-mentioned embodiments 1 and 2 are denoted by the same reference numerals, and duplicated descriptions will be omitted.

[0098] As shown in FIG. 18, the electric power steering device 100A is of a column assist type, and the electric drive device 1 applies an assist force to the steering shaft 92 and the output shaft 92B via the reduction gear device 75.

[0099] As shown in FIG. 19, the electric drive device 1 including the ECU 10 and the motor 30 is disposed in a reduction gear transmission 75. In this embodiment, the axial direction Ax refers to a direction parallel to the extension direction of the shaft 31 (see FIG. 3) of the motor 30. The axial direction Ax is often inclined with respect to the vertical direction VD. This is because the axial direction Ax is determined based on the space available in the vehicle 101 (see FIG. 1). For example, if the connector CNT is designed to be inserted and removed from a diagonally downward direction in the vertical direction VD, the opening 463A may face downward in the vertical direction VD.

[0100] (Embodiment 4) Fig. 20 is a schematic diagram of an electric power steering device according to a fourth embodiment. Note that the same components as those described in the first to third embodiments are assigned the same reference numerals, and redundant description will be omitted. A steering device 100B shown in Fig. 20 is of a pinion assist type that applies an assist steering torque to a first pinion shaft 99A. In the steering device 100B, a torque sensor 94 is connected to the first pinion shaft 99A.

[0101] The motor 30 rotates the worm shaft reduction gear 75. The worm wheel of the reduction gear 75 rotates integrally with the first pinion shaft 99A. This allows the motor 30 to rotate the first pinion gear 99B. The first pinion gear 99B meshes with the first rack 99D. As a result, the electric drive unit 1 applies an assist force to the first rack 99D via the reduction gear 75. The first pinion gear 99B may be disposed orthogonal to the first rack 99D, or may be disposed obliquely away from the orthogonal orientation. As described above, the steering device 100B of the fourth embodiment is of a single pinion assist type.

[0102] (Embodiment 5) FIG. 21 is a schematic diagram of an electric power steering device according to a fifth embodiment. Note that the same components as those described in the first to fourth embodiments are assigned the same reference numerals, and redundant description will be omitted. A steering device 100C includes an output shaft 92B and a second pinion gear 71B in addition to a first pinion shaft 99A and a first pinion gear 99B. A steering device 680 is of a dual pinion assist type. A torque sensor 94 detects the torque between a pinion shaft 95 and the first pinion gear 99B.

[0103] The motor 30 rotates the reduction gear 75 of the worm shaft. The worm wheel of the reduction gear 75 rotates integrally with the output shaft 92B. This allows the motor 30 to rotate the second pinion gear 71B. The second pinion gear 71B meshes with the second rack 71C. As a result, the electric drive unit 1 applies an assist force to the second rack 71C via the reduction gear 75. The second pinion gear 71B may be disposed orthogonal to the second rack 71C, or may be disposed obliquely away from the orthogonal orientation. The steering device 100C of the fifth embodiment is of a dual pinion assist type. [Explanation of symbols]

[0104] 1 Electric drive unit 10 ECU 20 Circuit Board 21 Board body 21a 2nd side 21b 1st page 23 Detection circuit 23a Rotation angle sensor 24 Control circuit 25A 1st power circuit 25B Second power circuit 30 motor 31 Shaft 31G Motor Gear 32 Magnet 33, 34 Bearings 40 Heatsink 41 Page 1 42 Side 2 44 Base 45H Hollow part 50 Lid 100 Electric power steering device 101 vehicles 930 Housing 931 stator core 931a Back Yoke 931b Teeth 932 Motor rotor 932a Rotor Yoke 932b Magnet 933 flange Ax axis direction BBT, BT1, BT2, CT bolts CNT Connector CNTQ corner CNTR recess

Claims

1. a shaft extending in an axial direction from a load side to a non-load side; a motor rotor coupled to the shaft; a motor stator including a stator core that rotates the motor rotor; a motor including a housing that accommodates the motor rotor and the motor stator therein; a magnet provided on the anti-load side of the shaft; a heat sink provided on the anti-load side of the motor; an electronic control device including a circuit board arranged on the anti-load side of the heat sink, and a rotation angle sensor located on an extension line of the axial direction of the magnet and attached to the circuit board; a connector that is inserted and removed radially from the shaft and is provided on the anti-load side of the heat sink, The connector has a first recess on a load side, the heat sink has a mounting surface on which the connector is mounted, and a protrusion that protrudes toward the anti-load side beyond the mounting surface and is fitted into the first recess, The heat sink has a second recess that surrounds the protrusion and is recessed toward the load side relative to the mounting surface.

2. a shaft extending in an axial direction from a load side to a non-load side; a motor rotor coupled to the shaft; a motor stator including a stator core that rotates the motor rotor; a motor including a housing that accommodates the motor rotor and the motor stator therein; a magnet provided on the anti-load side of the shaft; a heat sink provided on the anti-load side of the motor; an electronic control device including a circuit board arranged on the anti-load side of the heat sink, and a rotation angle sensor located on an extension line of the axial direction of the magnet and attached to the circuit board; a connector that is inserted and removed radially from the shaft and is provided on the anti-load side of the heat sink, The connector has a first recess on a load side, the heat sink has a mounting surface on which the connector is mounted, and a protrusion that protrudes toward the anti-load side beyond the mounting surface and is fitted into the first recess, the heat sink further has a first surface located on the anti-load side of the mounting surface and a second surface located on the anti-load side of the first surface, the second surface facing the circuit board and serving as a heat dissipation surface for dissipating heat from the circuit board; a step surface between the first surface and the mounting surface, and a portion of the connector is inserted between the protrusion.

3. a shaft extending in an axial direction from a load side to a non-load side; a motor rotor coupled to the shaft; a motor stator including a stator core that rotates the motor rotor; a motor including a housing that accommodates the motor rotor and the motor stator therein; a magnet provided on the anti-load side of the shaft; a heat sink provided on the anti-load side of the motor; an electronic control device including a circuit board arranged on the anti-load side of the heat sink, and a rotation angle sensor located on an extension line of the axial direction of the magnet and attached to the circuit board; a connector that is inserted and removed radially from the shaft and is provided on the anti-load side of the heat sink, The connector has a first recess on a load side, the heat sink has a mounting surface on which the connector is mounted, and a protrusion that protrudes toward the anti-load side beyond the mounting surface and is fitted into the first recess, The electric drive device, wherein the protrusion is a prism.

4. a shaft extending in an axial direction from a load side to a non-load side; a motor rotor coupled to the shaft; a motor stator including a stator core that rotates the motor rotor; a motor including a housing that accommodates the motor rotor and the motor stator therein; a magnet provided on the anti-load side of the shaft; a heat sink provided on the anti-load side of the motor; an electronic control device including a circuit board arranged on the anti-load side of the heat sink, and a rotation angle sensor located on an extension line of the axial direction of the magnet and attached to the circuit board; a connector that is inserted and removed radially from the shaft and is provided on the anti-load side of the heat sink, The connector has a first recess on a load side, the heat sink has a mounting surface on which the connector is mounted, and a protrusion that protrudes toward the anti-load side beyond the mounting surface and is fitted into the first recess, An electric drive device, wherein the first recess is provided midway between both ends of the connector in the radial direction of the shaft.

5. A cover is further provided to cover the anti-load side of the circuit board. the heat sink includes a base having the mounting surface and the protrusion, The electric drive device according to claim 1 , wherein the connector is sandwiched between an end of the cover and the base.

6. The electric drive device according to claim 5 , wherein an end of the cover is disposed between the protrusion and a radially outer end of the base as viewed in the radial direction of the shaft.

7. The electric drive device according to claim 5 or 6, wherein the connector includes a plurality of ribs extending in a radial direction of the shaft, and the end of the cover is adjacent to the ribs.

8. The electric drive device according to claim 1 , wherein the heat sink has a third recess that accommodates a head of a first bolt that fastens the motor and is recessed toward the load side relative to the mounting surface.

9. The electric drive device according to claim 1 , wherein the connector is sandwiched between the heat sink and the circuit board, and the circuit board and the connector are fixed together by a second bolt.

10. The electric drive device according to claim 9 , further comprising a third bolt that fastens the circuit board and the heat sink to a position adjacent to the second bolt.

11. The electric drive device according to claim 1 , wherein the heat sink is made of a metal material, and the connector is made of a resin material.

12. The electric drive device according to any one of claims 1 to 11, An electric power steering device in which the electric drive device generates an auxiliary steering torque.

Images