Electric Actuator

Abstract

To provide an electric actuator which can suppress performance deterioration of a motor.SOLUTION: One embodiment of an electric actuator comprises: a motor part 20; a magnet 40; a bus bar 150; a bus bar holder 140 which holds the bus bar 150; a magnetic sensor 63 which is fixed to the bus bar holder 140, and can detect a magnetic field of the magnet 40; a conductive wire 64 electrically connected with the magnetic sensor 63; and a circuit board 70 electrically connected with the motor part 20. The magnetic sensor 63 is arranged opposite to one side in an axial direction of the magnet 40 via a gap, the conductive wire 64 penetrates the bus bar holder 140 from the inside of the bus bar holder 140, and is electrically connected with the circuit board 70.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an electric actuator. [Background technology]

[0002] It is known that in controlling the rotation of a motor in an electric actuator, a magnetic sensor is used to detect changes in the magnetic field. For example, Patent Document 1 discloses a configuration in which a magnet is attached to the motor shaft so that it is in phase with the magnetic poles of the rotor, using a magnetic sensor located on a circuit board. A commonly used method is to directly detect the magnetic poles of the rotor using a magnetic sensor without attaching a magnet to the motor shaft. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-198191 Summary of the Invention [Problem to be solved by the invention]

[0004] In the method of directly detecting the magnetic poles of the rotor using a magnetic sensor, a phase shift occurs between the rotor and the magnet, which is installed so that it is in phase with the magnetic poles of the rotor. This can result in a delay in the timing of current flow due to a shift in the detection timing by the sensor, which can degrade the performance of the motor.

[0005] The present invention has been made in consideration of the above points, and an object of the present invention is to provide an electric actuator that can suppress deterioration in motor performance. [Means for solving the problem]

[0006] One aspect of the electric actuator of the present invention comprises a motor unit having a rotor rotatable about a central axis extending in the axial direction and a stator radially facing the rotor with a gap therebetween, a magnet fixed to the rotor, a bus bar electrically connected to the motor unit, a bus bar holder arranged on one axial side of the rotor and holding the bus bar, a magnetic sensor fixed to the bus bar holder and capable of detecting the magnetic field of the magnet, a conductive wire electrically connected to the magnetic sensor, and a circuit board arranged on one axial side of the bus bar holder and electrically connected to the motor unit, wherein the magnetic sensor is arranged on one axial side of the magnet facing the magnet with a gap therebetween, and the conductive wire passes through the bus bar holder from inside the bus bar holder and is electrically connected to the circuit board. [Effects of the Invention]

[0007] According to one aspect of the present invention, it is possible to suppress a decrease in motor performance in an electric actuator. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a cross-sectional view showing an electric actuator according to a first embodiment. [Figure 2] FIG. 2 is a cross-sectional view showing the electric actuator of the first embodiment, taken along line II-II in FIG. [Figure 3] FIG. 3 is a schematic cross-sectional view showing a part of the electric actuator of the first embodiment. [Figure 4] FIG. 4 is a cross-sectional view showing a bus bar holder according to the second embodiment. [Figure 5] FIG. 5 is a cross-sectional view showing the bus bar holder of the second embodiment, taken along line VV in FIG. [Figure 6] FIG. 6 is a cross-sectional view showing a part of a procedure for fixing the bus bar holder and the magnetic sensor according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an electric actuator according to an embodiment of the present invention will be described with reference to the drawings. Note that the scope of the present invention is not limited to the following embodiments, and can be modified as desired within the scope of the technical concept of the present invention. In addition, in the following drawings, the scale and number of each structure may differ from the actual structure in order to make each configuration easier to understand.

[0010] In each figure, the Z-axis direction is the up-down direction with the positive side at the top and the negative side at the bottom. The axial direction of the central axis J1 shown appropriately in each figure is parallel to the Z-axis direction, i.e., the up-down direction. In the following description, unless otherwise specified, the direction parallel to the axial direction of the central axis J1 will simply be referred to as the "axial direction." Furthermore, unless otherwise specified, the radial direction centered on the central axis J1 will simply be referred to as the "radial direction," and the circumferential direction centered on the central axis J1 will simply be referred to as the "circumferential direction."

[0011] In the following embodiments, the upper side corresponds to one axial side, and the lower side corresponds to the other axial side. Note that the terms upper side and lower side are simply names used to describe the relative positional relationship of each part, and the actual positional relationship may be one other than the positional relationship indicated by these names.

[0012] First Embodiment 1 to 3, the electric actuator 10 of this embodiment is an electric actuator mounted on, for example, a vehicle. As shown in Fig. 1 and 3, the electric actuator 10 includes a case 11, a partition member 15, a motor unit 20 having a motor shaft 21 that rotates about a central axis J1, a first bearing 53, a second bearing 51, a third bearing 52, a speed reduction mechanism 30, an output shaft 41, a magnetic sensor 63, a circuit board 70, and a bus bar holder 140.

[0013] 1, case 11 houses partition member 15, motor section 20, motor shaft 21, speed reduction mechanism 30, output shaft 41, magnetic sensor 63, circuit board 70, and bus bar holder 140. Case 11 has lower case 11A that opens upward, and upper case 11B that is fixed to the opening of lower case 11A.

[0014] The lower case 11A has a cylindrical shape extending in the axial direction about the central axis J1. The lower case 11A has a board accommodating portion 13a, a case cylindrical portion 13b, an output portion accommodating portion 13c, and a bearing holding portion 13d. The board accommodating portion 13a is a portion that accommodates the circuit board 70 and the bus bar holder 140. The board accommodating portion 13a opens upward. The board accommodating portion 13a is configured radially inward of the upper portion of the lower case 11A. The bottom surface of the board accommodating portion 13a is a support surface 12 that supports and fixes the circuit board 70 and the bus bar holder 140. The support surface 12 faces upward.

[0015] The case cylindrical portion 13b surrounds the radial outside of the motor portion 20. The output portion accommodating portion 13c is a portion that accommodates the output portion 46, which will be described later. The bearing holding portion 13d holds the third bearing 52. The bearing holding portion 13d extends upward from the lower end of the case 11 around the central axis J1.

[0016] The upper case 11B is a container-shaped member having a recess 16a that opens downward. The upper case 11B and the lower case 11A are fastened together by a plurality of bolts that pass through the upper case 11B in the axial direction. In this embodiment, the upper case 11B corresponds to a lid that covers the opening of the lower case 11A from above. The upper case 11B has a bearing holder 16b. The bearing holder 16b holds the first bearing 53. The bearing holder 16b extends downward about the central axis J1.

[0017] The motor section 20 has a central axis J1. As shown in Fig. 1, the motor section 20 has a rotor 22 and a stator 23. The rotor 22 has a motor shaft 21, a rotor core 22a, and a magnet 40.

[0018] The motor shaft 21 includes a first shaft portion 21a, a second shaft portion 21b, and a through hole 25. The first shaft portion 21a extends axially and is located on the upper side of the motor shaft 21. The second shaft portion 21b extends axially and is located on the lower side of the motor shaft 21. The diameter of the second shaft portion 21b is larger than the diameter of the first shaft portion 21a. More specifically, the outer diameter of the second shaft portion 21b is larger than the outer diameter of the first shaft portion 21a. The second shaft portion 21b is an eccentric shaft portion centered on an eccentric axis J2 that is eccentric with respect to the central axis J1. The eccentric axis J2 is parallel to the central axis J1. The through hole 25 extends about the central axis J1. Therefore, the first shaft portion 21a is cylindrical and extends about the central axis J1. The second shaft portion 21b has an axial recess 26 on its lower side. The recessed portion 26 extends around the eccentric axis J2. Therefore, the second shaft portion 21b has a cylindrical shape that extends around the eccentric axis J2. The upper side of the recessed portion 26 is connected to the lower side of the through-hole 25. The second shaft portion 21b of the motor shaft 21 is supported by the third bearing 52 so as to be rotatable around the eccentric axis J2.

[0019] The rotation of the motor shaft 21 is transmitted to the output shaft 41 via the reduction mechanism 30 . The output shaft 41 has a shaft portion 41a and a connecting portion 42. The shaft portion 41a is located on the upper side, and the connecting portion 42 is located on the lower side. The shaft portion 41a is cylindrical and extends about the central axis J1. The upper side of the shaft portion 41a passes through the through hole 25 of the motor shaft 21. The upper end of the shaft portion 41a protrudes upward from the motor shaft 21. The upper end of the shaft portion 41a protruding upward from the motor shaft 21 is supported by a first bearing 53 so as to be rotatable around the central axis J1. The upper end of the motor shaft 21 is supported by the case 11 via the first bearing 53.

[0020] The lower end of the connecting portion 42 protrudes below the motor shaft 21. The lower end of the connecting portion 42 protruding below the motor shaft 21 is supported by the second bearing 51 so as to be rotatable about the central axis J1. The lower end of the motor shaft 21 is supported by the case 11 via the second bearing 51. The axial end of the output shaft 41 is supported by the first bearing 53 and the second bearing 51 so as to be rotatable about the central axis J1. Therefore, the motor shaft 21, with the shaft portion 41a of the output shaft 41 passing through the through hole 25, is supported by the shaft portion 41a so as to be rotatable about the central axis J1.

[0021] The first bearing 53, the second bearing 51, and the third bearing 52 are each a rolling bearing having an inner ring and an outer ring located radially outward of the inner ring. In this embodiment, the first bearing 53, the second bearing 51, and the third bearing 52 are, for example, ball bearings in which the inner ring and the outer ring are connected via a plurality of balls.

[0022] The upper side of the connecting portion 42 is inserted into the recessed portion 26 of the motor shaft 21. By inserting the upper side of the connecting portion 42 into the recessed portion 26 of the motor shaft 21, the axial length of the output shaft 41 can be shortened. Therefore, the axial length of the electric actuator 10 can be shortened, and the size can be reduced.

[0023] The connecting portion 42 has a cylindrical tubular portion 44 extending about the central axis J1. A connecting recess 45 is provided on the inner diameter of the tubular portion 44. The connecting recess 45 is recessed upward from the lower end of the output shaft 41. When viewed along the axial direction, the connecting recess 45 has a substantially circular shape centered on the central axis J1. A plurality of spline grooves are provided on the inner peripheral surface of the connecting recess 45 along the circumferential direction. Another member to which the driving force of the electric actuator 10 is output is inserted and connected to the connecting recess 45. The other member is, for example, a manual shaft in a vehicle. The electric actuator 10 drives the manual shaft based on a shift operation by the driver to change gears of the vehicle.

[0024] Because the connecting portion 42 has the connecting recess 45 recessed upward, the axial length of the output shaft 41 can be shortened compared to when the connecting portion 42 is axially shaped and protrudes downward. Therefore, the axial length of the electric actuator 10 can be shortened, thereby making it more compact. The first bearing 53 is held by the bearing holder 16b provided on the case 11, and the second bearing 51 is held by the bearing holder 13d provided on the case 11, thereby improving the concentricity of the output shaft 41 with respect to the central axis J1. The first bearing 53 is held by the bearing holder 16b provided on the case 11, and the second bearing 51 is held by the bearing holder 13d provided on the case 11, thereby eliminating the need to provide separate holders for the first bearing 53 and the second bearing 51, which contributes to cost reduction and a more compact electric actuator 10.

[0025] The rotor core 22a is fixed to the outer peripheral surface of the motor shaft 21. More specifically, the rotor core 22a is fixed to the outer peripheral surface of the first shaft portion 21a. The peripheral edge of the rotor core 22a is supported from below by a partition member 15 (described later) that is supported from below by the lower case 11A. The partition member 15 is a support member that supports the rotor core 22a from below. The magnet 40 is fixed to the radial outside of the rotor core 22a. Multiple magnets 40 are arranged at intervals in the circumferential direction.

[0026] The stator 23 is located radially outside the rotor 22. The stator 23 has a stator core 23a and multiple coils 23b. The stator core 23a is annular and surrounds the radially outside of the rotor 22. An outer peripheral surface 24a of the stator core 23a is fixed to an inner peripheral surface of the cylindrical case portion 13b. The multiple coils 23b are attached to the teeth of the stator core 23a, for example, via insulators (not shown).

[0027] As shown in FIG. 2, the stator 23 has an outer peripheral surface 24b radially inward of the outer peripheral surface 24a. The outer peripheral surface 24b is arranged for each magnetic pole. When viewed in the axial direction, the outer peripheral surface 24b is perpendicular to the circumferential center of the magnetic pole. Grooves 27 recessed radially inward are provided in the outer peripheral surface 24b of the stator 23. The grooves 27 extend in the axial direction. The grooves 27 are arranged above and below the outer peripheral surface 24a of the stator core 23a. A plurality of grooves 27 are arranged at intervals in the circumferential direction.

[0028] The bus bar holder 140 is disposed above the rotor 22. The bus bar holder 140 has an annular plate shape. As shown in FIG. 1 , the bus bar holder 140 has a spacer 143. The spacer 143 has a cylindrical shape extending in the axial direction. The spacer 143 protrudes above the bus bar holder 140. The upper end of the spacer 143 contacts the lower side of the circuit board 70. The bus bar holder 140 and the circuit board 70 are screwed to the support surface 12 of the lower case 11A from above by bolts 144 that pass through the circuit board 70 and the spacer 143. For example, three bolts 144 are provided. The bus bar holder 140 and the circuit board 70 are screwed to each other from above by the bolts 144 at positions that overlap the spacer 143 when viewed in the axial direction. The screwed circuit board 70 is disposed above the bus bar holder 140 with a gap therebetween. The dimension of the gap between the circuit board 70 and the bus bar holder 140 is such that the spacer 143 protrudes upward from the bus bar holder 140 .

[0029] The bus bar holder 140 has a peripheral wall portion 141 extending downward. The peripheral wall portion 141 is located radially outward from the outer peripheral surface 24b of the stator 23. The peripheral wall portion 141 is located radially inward from the outer peripheral surface 24a of the stator 23. The lower end of the peripheral wall portion 141 comes into contact with the upper side of the stator 23 when the bus bar holder 140 is screwed to the support surface 12.

[0030] When the busbar holder 140 is screwed to the support surface 12 of the lower case 11A, the lower end of the peripheral wall portion 141 comes into contact with the upper side of the stator 23, and the stator 23, which is supported from below by the partition member 15, is positioned and fixed axially to the lower case 11A.

[0031] As shown in FIG. 2 , peripheral wall portion 141 of busbar holder 140 has protrusions 142 that protrude radially inward. Protrusions 142 extend in the axial direction. The circumferential position of protrusions 142 is the same as the circumferential position of grooves 27 of stator 23. Protrusions 142 face grooves 27 in the radial direction. Protrusions 142 that protrude radially inward from peripheral wall portion 141 are inserted into grooves 27. Busbar holder 140 with protrusions 142 inserted into grooves 27 is positioned circumferentially with respect to stator 23. When busbar holder 140 is accommodated in board accommodating portion 13a while protrusions 142 are inserted from above into grooves 27 that open upward, busbar holder 140 can be positioned circumferentially with respect to stator 23 and lower case 11A. Therefore, when bus bar holder 140 is screwed to support surface 12 of lower case 11A, bus bar holder 140, stator 23, and lower case 11A can be positioned relative to each other in the circumferential and axial directions.

[0032] The bus bar holder 140 holds the magnetic sensor 63, the conductive wires 64, and the plurality of bus bars 150. In this embodiment, the bus bar holder 140, the magnetic sensor 63, the conductive wires 64, the spacer 143, and the plurality of bus bars 150 are molded from resin into an integrated molded body. More specifically, the bus bar holder 140 is made by insert molding, with the magnetic sensor 63, the conductive wires 64, the spacer 143, and the bus bars 150 as insert members.

[0033] The magnetic sensor 63 can detect the magnetic field of the magnet 40. The magnetic sensor 63 is, for example, a Hall element. The magnetic sensor 63 is fixed to the lower side of the bus bar holder 140. The magnetic sensor 63 is arranged above the magnet, facing it with a gap between them. As shown in FIG. 2, three magnetic sensors 63 are arranged at intervals in the circumferential direction. The circumferential intervals between the magnetic sensors 63 are the same as the circumferential intervals between the magnetic poles. The magnetic sensor 63 detects the magnetic field of the magnet 40 to detect the rotational position of the magnet 40 and thereby detect the rotation of the motor shaft 21.

[0034] According to the electric actuator 10 of this embodiment, the magnetic sensor 63, which is disposed below the bus bar holder 140 so as to be able to face the magnet 40, directly detects the magnetic field of the magnet 40, so that there is little deviation in the detection timing by the magnetic sensor 63. Therefore, according to the electric actuator 10 of this embodiment, it is possible to suppress a phase shift between the magnet 40 and the rotor 22. By suppressing the phase shift between the magnet 40 and the rotor 22, it is possible to suppress a delay in the energization timing caused by a deviation in the detection timing by the magnetic sensor 63, and it is possible to suppress a deterioration in motor performance. According to the electric actuator 10 of this embodiment, because the magnetic sensor 63 is provided on the bus bar holder 140, there is no need for a separate extra circuit board for mounting the magnetic sensor. According to the electric actuator 10 of this embodiment, the magnetic sensor 63 and the bus bar holder 140 are molded from resin and are an integrated molded body. When the bus bar holder 140 is assembled by screwing it to the support surface 12 of the lower case 11A, it can be positioned circumferentially and axially with respect to the stator 23. According to the electric actuator 10 of this embodiment, it is possible to prevent a decrease in the accuracy of motor rotation control due to an advance angle deviation that occurs depending on assembly accuracy.

[0035] One end of the conductive wire 64 is electrically connected to the magnetic sensor 63. The conductive wire 64 may be a terminal extending from the magnetic sensor 63, or may be a bus bar having one end connected to the magnetic sensor 63. The conductive wire 64 passes through the bus bar holder 140 from inside the bus bar holder 140, and the other end is electrically connected to the circuit board 70 by a connection method such as soldering, welding, or press fitting.

[0036] The circuit board 70 has a plate shape extending in a plane perpendicular to the axial direction. The circuit board 70 is housed in the lower case 11A. More specifically, the circuit board 70 is housed in the board housing portion 13a. The circuit board 70 is a board that is electrically connected to the motor unit 20. The circuit board 70 controls, for example, the current supplied to the motor unit 20. That is, the circuit board 70 has, for example, an inverter circuit mounted thereon.

[0037] As shown in FIG. 3 , one end 150a of the bus bar 150 grips a coil lead wire drawn from the coil 23b of the stator 23 and is connected to the coil 23b by soldering or welding. The other end 150b of the bus bar 150 protrudes upward from the upper surface of the bus bar holder 140. In this embodiment, the other end 150b of the bus bar 150 penetrates the circuit board 70 from bottom to top. The end 150b is electrically connected to the circuit board 70 at a position where it penetrates the circuit board 70 by a connection method such as soldering, welding, or press-fitting. As a result, the circuit board 70 is electrically connected to the motor unit 20 via the bus bar 150.

[0038] The reduction mechanism 30 is disposed radially outside the second shaft portion 21b of the motor shaft 21 and radially outside the connecting portion 42 of the output shaft 41. The reduction mechanism 30 is disposed below the motor portion 20. The partition member 15 is disposed axially between the stator 23 and the reduction mechanism 30. The reduction mechanism 30 has an external gear 31, an internal gear 32, an output portion 46, and a plurality of protrusions 43.

[0039] The external gear 31 is annular and has a plate shape that extends radially about the eccentric axis J2 of the second shaft portion 21b. A gear portion is provided on the radially outer surface of the external gear 31. The gear portion of the external gear 31 has a plurality of teeth arranged along the outer periphery of the external gear 31.

[0040] The external gear 31 is connected to the motor shaft 21. More specifically, the external gear 31 is connected to the second shaft portion 21b of the motor shaft 21 via the third bearing 52. In this way, the motor shaft 21 is connected to the reduction gear mechanism 30. The external gear 31 is fitted into the outer ring of the third bearing 52 from the outside in the radial direction. The second shaft portion 21b is fitted into the inner ring of the third bearing 52 from the outside in the radial direction. In this way, the third bearing 52 connects the motor shaft 21 and the external gear 31 to be relatively rotatable around the eccentric axis J2.

[0041] In this embodiment, the external gear 31 has a plurality of holes 31a. In this embodiment, the holes 31a penetrate the external gear 31 in the axial direction. The plurality of holes 31a are arranged along the circumferential direction. More specifically, the plurality of holes 31a are arranged at equal intervals around one circumference along the circumferential direction centered on the eccentric axis J2. The holes 31a are circular when viewed in the axial direction. The inner diameter of the hole 31a is larger than the outer diameter of the protrusion 43. Note that the hole 31a may be a hole having a bottom.

[0042] The internal gear 32 is located radially outside the external gear 31 and has an annular shape surrounding the external gear 31. In this embodiment, the internal gear 32 has an annular shape centered on the central axis J1. The radially outer edge of the internal gear 32 is disposed and fixed to a stepped portion 13e recessed radially inward on the inner circumferential surface of the case cylindrical portion 13b. This allows the reduction mechanism 30 to be held in the lower case 11A. The internal gear 32 meshes with the external gear 31. A gear portion is provided on the radially inner surface of the internal gear 32. The gear portion of the internal gear 32 has a plurality of teeth aligned along the inner circumference of the internal gear 32. In this embodiment, the gear portion of the internal gear 32 meshes with the gear portion of the external gear 31 only partially in the circumferential direction.

[0043] The output portion 46 has an annular plate shape that expands radially around the central axis J1. The output portion 46 is located below the external gear 31. The output portion 46 is fixed to the outer circumferential surface of the output shaft 41. More specifically, the output portion 46 is fixed to the outer circumferential surface of the connecting portion 42 of the output shaft 41.

[0044] The multiple protrusions 43 are fixed to the output portion 46 by, for example, welding. The multiple protrusions 43 protrude upward from the output portion 46. That is, the multiple protrusions 43 protrude from the output portion 46 toward the external gear 31. The multiple protrusions 43 are cylindrical. The multiple protrusions 43 are arranged along the circumferential direction. More specifically, the multiple protrusions 43 are arranged at equal intervals around one circumference along the circumferential direction centered on the central axis J1. The number of protrusions 43 is, for example, eight.

[0045] The multiple protrusions 43 are inserted into the multiple hole portions 31a, respectively. The outer peripheral surfaces of the protrusions 43 are inscribed in the inner peripheral surfaces of the hole portions 31a. As a result, the multiple protrusions 43 support the external gear 31 via the inner surfaces of the hole portions 31a so that the external gear 31 can swing around the central axis J1.

[0046] In this embodiment, the hole 31a and the protrusion 43 overlap with the third bearing 52 and the second shaft portion 21b when viewed in the radial direction. In other words, the hole 31a, the protrusion 43, the third bearing 52, and the second shaft portion 21b each have portions that are located at the same positions as each other in the axial direction.

[0047] When the motor shaft 21 rotates around the central axis J1, the second shaft portion 21b, which is an eccentric shaft portion, revolves in the circumferential direction around the central axis J1. The revolution of the second shaft portion 21b is transmitted to the external gear 31 via the third bearing 52, and the external gear 31 oscillates while changing the position at which the inner circumferential surface of the hole 31a and the outer circumferential surface of the protrusion 43 are inscribed. As a result, the position at which the gear portion of the external gear 31 and the gear portion of the internal gear 32 mesh changes in the circumferential direction. Therefore, the rotational force of the motor shaft 21 is transmitted to the internal gear 32 via the external gear 31.

[0048] In this embodiment, the internal gear 32 is fixed and therefore does not rotate. Therefore, the external gear 31 rotates around the eccentric axis J2 due to a reaction force of the rotational force transmitted to the internal gear 32. At this time, the direction of rotation of the external gear 31 is opposite to the direction of rotation of the motor shaft 21. The rotation of the external gear 31 around the eccentric axis J2 is transmitted to the output portion 46 via the hole portion 31a and the protrusion portion 43. As a result, the output shaft 41 rotates around the central axis J1. In this way, the rotation of the motor shaft 21 is transmitted to the output shaft 41 via the reduction mechanism 30.

[0049] The rotation of the output shaft 41 is reduced relative to the rotation of the motor shaft 21 by the reduction gear mechanism 30. Specifically, in the configuration of the reduction gear mechanism 30 of this embodiment, the reduction ratio R of the rotation of the output shaft 41 relative to the rotation of the motor shaft 21 is expressed as R = -(N2 - N1) / N2. The minus sign at the beginning of the equation expressing the reduction ratio R indicates that the direction of rotation of the reduced output shaft 41 is opposite to the direction of rotation of the motor shaft 21. N1 is the number of teeth of the external gear 31, and N2 is the number of teeth of the internal gear 32. As an example, if the number of teeth N1 of the external gear 31 is 59 and the number of teeth N2 of the internal gear 32 is 60, the reduction ratio R is -1 / 60.

[0050] Thus, according to the reduction gear mechanism 30 of this embodiment, it is possible to make the reduction ratio R of the rotation of the output shaft 41 relative to the rotation of the motor shaft 21 relatively large. Therefore, it is possible to make the rotation torque of the output shaft 41 relatively large.

[0051] Second Embodiment 4 to 6, the X-axis direction is a direction orthogonal to the axial direction. A direction parallel to the X-axis direction is called the orthogonal direction. The side of the orthogonal direction toward which the X-axis arrow points is called one orthogonal direction side. The orthogonal direction is a direction defined for each magnetic sensor 263. In this embodiment, the orthogonal direction in each magnetic sensor 263 is a direction orthogonal to both the axial direction and the radial direction passing through each magnetic sensor 263. In other words, in FIGS. 4 to 6, the direction orthogonal to both the X-axis direction and the Z-axis direction is the radial direction.

[0052] As shown in FIGS. 4 and 5 , in the electric actuator 210 of this embodiment, the bus bar holder 240 holds a magnetic sensor 263 and a plurality of bus bars 150. Although not shown, in this embodiment, the bus bar holder 240 and the plurality of bus bars 150 are molded into an integrated body by resin molding. More specifically, the bus bar holder 240 is formed by insert molding using a spacer 143 and the bus bar 150 as insert members. In this embodiment, unlike the first embodiment, the magnetic sensor 263 and conductive wires 264, 265, and 266 are attached to the bus bar holder 240 after insert molding. In this embodiment, the bus bar holder 240 has a magnetic sensor accommodating hole 240d, a first through hole 240a, a second through hole 240b, and a third through hole 240c.

[0053] The magnetic sensor accommodating hole 240d opens downward and accommodates the magnetic sensor 263. The magnetic sensor accommodating hole 240d is recessed upward from the lower surface of the bus bar holder 240. The magnetic sensor accommodating hole 240d is a hole with a bottom on the upper side. When viewed in the axial direction, the magnetic sensor accommodating hole 240d is approximately rectangular. Two of the inner surfaces of the magnetic sensor accommodating hole 240d face in the radial direction. The upper part of the magnetic sensor 263 is accommodated inside the magnetic sensor accommodating hole 240d. The orthogonal dimension of the magnetic sensor accommodating hole 240d is larger than the orthogonal dimension of the magnetic sensor 263. The radial dimension of the magnetic sensor accommodating hole 240d is approximately the same as the radial dimension of the magnetic sensor 263. Although not shown in the drawings, in this embodiment, three magnetic sensor accommodating holes 240d are arranged at intervals in the circumferential direction. The inner surface of the magnetic sensor receiving hole 240d is provided with a first inclined surface 240e, a second inclined surface 240f, a first support surface 240g, and a second support surface 240h.

[0054] As shown in FIG. 4, the first inclined surface 240e and the second inclined surface 240f are provided on the upper inner surface of the magnetic sensor housing hole 240d. The first inclined surface 240e and the second inclined surface 240f are surfaces facing downward and inclined with respect to a plane perpendicular to the axial direction. The first inclined surface 240e and the second inclined surface 240f are arranged with a gap in between in the perpendicular direction. In this embodiment, the first inclined surface 240e and the second inclined surface 240f are arranged with a third through-hole 240c (described later) sandwiched therebetween in the perpendicular direction. The first inclined surface 240e and the second inclined surface 240f are arranged symmetrically with each other in the perpendicular direction. The first inclined surface 240e is located on the other side (-X side) of the second inclined surface 240f in the perpendicular direction.

[0055] The first inclined surface 240e is positioned upward as it approaches the other orthogonal side (-X side). An end of the first inclined surface 240e that is farther from the second inclined surface 240f in the orthogonal direction is connected to a lower end of the first through-hole 240a. An end of the first inclined surface 240e that is closer to the second inclined surface 240f in the orthogonal direction is positioned closer to the second inclined surface 240f (+X side) in the orthogonal direction than a first connecting portion 264a (described later). In this embodiment, the end of the first inclined surface 240e that is closer to the second inclined surface 240f in the orthogonal direction is positioned between the first connecting portion 264a and a third connecting portion 266a (described later) in the orthogonal direction.

[0056] In this embodiment, the end of the first inclined surface 240e farthest from the second inclined surface 240f in the orthogonal direction is the end of the first inclined surface 240e on the other orthogonal direction side (-X side) and is the uppermost part of the first inclined surface 240e. The end of the first inclined surface 240e closer to the second inclined surface 240f in the orthogonal direction is the end of the first inclined surface 240e on one orthogonal direction side (+X side) and is the lowermost part of the first inclined surface 240e.

[0057] The second inclined surface 240f is positioned higher as it moves toward one side (+X side) in the orthogonal direction. That is, the first inclined surface 240e and the second inclined surface 240f are positioned higher as they move away from each other in the orthogonal direction. The end of the second inclined surface 240f farther from the first inclined surface 240e in the orthogonal direction is connected to the lower end of the second through-hole 240b. The end of the second inclined surface 240f closer to the first inclined surface 240e in the orthogonal direction is positioned closer to the first inclined surface 240e (-X side) in the orthogonal direction than the second connecting portion 265a described later. In this embodiment, the end of the second inclined surface 240f closer to the first inclined surface 240e in the orthogonal direction is positioned between the second connecting portion 265a and the third connecting portion 266a described later in the orthogonal direction.

[0058] In this embodiment, the end of the second inclined surface 240f farthest from the first inclined surface 240e in the orthogonal direction is the end of the second inclined surface 240f on one side (+X side) of the orthogonal direction, which is the uppermost portion of the second inclined surface 240f. The end of the second inclined surface 240f closer to the first inclined surface 240e in the orthogonal direction is the end of the second inclined surface 240f on the other side (-X side) of the orthogonal direction, which is the lowermost portion of the second inclined surface 240f.

[0059] As shown in FIG. 5, the first support surface 240g and the second support surface 240h are each part of the upper inner surface of the magnetic sensor accommodating hole 240d. The first support surface 240g is located at the radially inner end of the magnetic sensor accommodating hole 240d. The second support surface 240h is located at the radially outer end of the magnetic sensor accommodating hole 240d. The first support surface 240g and the second support surface 240h each face downward. The first support surface 240g and the second support surface 240h each contact the upward-facing surface of the magnetic sensor 263.

[0060] As shown in FIG. 4, the first through hole 240a, the second through hole 240b, and the third through hole 240c are holes that extend upward from the magnetic sensor accommodating hole 240d and open to the upper side of the bus bar holder 240. The first through hole 240a, the second through hole 240b, and the third through hole 240c are, for example, circular holes. In this embodiment, the first through hole 240a, the second through hole 240b, and the third through hole 240c are arranged at intervals in the perpendicular direction. In this embodiment, the first through hole 240a and the second through hole 240b are arranged so that the third through hole 240c is sandwiched between them in the perpendicular direction.

[0061] The first through hole 240a extends upward from the end of the magnetic sensor accommodating hole 240d on the other orthogonal side (-X side). The second through hole 240b extends upward from the end of the magnetic sensor accommodating hole 240d on one orthogonal side (+X side). The third through hole 240c extends upward from the center of the magnetic sensor accommodating hole 240d in the orthogonal direction. The lower end of the third through hole 240c opens into a portion of the upper inner surface of the magnetic sensor accommodating hole 240d that is located between the first inclined surface 240e and the second inclined surface 240f in the orthogonal direction. The lower end of the first through hole 240a and the lower end of the second through hole 240b are located above the lower end of the third through hole 240c.

[0062] The orthogonal distance between the first through hole 240a and the second through hole 240b is larger than the orthogonal distance between the first connection portion 264a and the second connection portion 265a (described later). The orthogonal distance between the first through hole 240a and the third through hole 240c is larger than the orthogonal distance between the first connection portion 264a and the third connection portion 266a (described later). The orthogonal distance between the second through hole 240b and the third through hole 240c is larger than the orthogonal distance between the second connection portion 265a and the third connection portion 266a (described later). A first conductive wire 264, a second conductive wire 265, and a third conductive wire 266 (described later) are respectively passed through the first through hole 240a, the second through hole 240b, and the third through hole 240c. The other configurations of the bus bar holder 240 are similar to those of the bus bar holder 140 of the first embodiment.

[0063] As shown in FIG. 4, in the electric actuator 210 of this embodiment, an upper portion of the magnetic sensor 263 is accommodated inside the magnetic sensor accommodating hole 240d. More specifically, the entire magnetic sensor 263, except for its lower end, is accommodated inside the magnetic sensor accommodating hole 240d. As shown in FIG. 5, in this embodiment, the radially inward and radially outward surfaces of the magnetic sensor 263 are in contact with and fixed to the inner surface of the magnetic sensor accommodating hole 240d. As described above, the upward surface of the magnetic sensor 263 is in contact with the first support surface 240g and the second support surface 240h. This determines the position of the magnetic sensor 263 relative to the bus bar holder 240 in the axial direction. Although not shown, in this embodiment, as in the first embodiment, three magnetic sensors 263 are arranged at intervals in the circumferential direction. The other configuration of the magnetic sensor 263 is the same as that of the magnetic sensor 63 of the first embodiment.

[0064] As shown in FIG. 4 , in the electric actuator 210 of this embodiment, three conductive wires, a first conductive wire 264, a second conductive wire 265, and a third conductive wire 266, are connected to each magnetic sensor 263. In this embodiment, the lower ends of the first conductive wire 264, the second conductive wire 265, and the third conductive wire 266 are terminals electrically connected to the magnetic sensor 263. The first conductive wire 264, the second conductive wire 265, and the third conductive wire 266 each extend upward from the magnetic sensor 263. The first conductive wire 264, the second conductive wire 265, and the third conductive wire 266 are arranged at intervals in the orthogonal direction. In this embodiment, the first conductive wire 264 and the second conductive wire 265 are arranged with the third conductive wire 266 sandwiched between them in the orthogonal direction. The first conductive wire 264 is arranged on the other orthogonal side (−X side) of the third conductive wire 266. The second conductive wire 265 is disposed on one side in the orthogonal direction (+X side) of the third conductive wire 266. An upper end of the first conductive wire 264, an upper end of the second conductive wire 265, and an upper end of the third conductive wire 266 each pass through the bus bar holder 240 from the magnetic sensor accommodating hole 240d and are electrically connected to the circuit board 270 by solder 280.

[0065] In the present embodiment, the first conductive wire 264 is formed by bending a portion of a conductive wire extending linearly in the axial direction toward the other orthogonal direction side (-X side). In the present embodiment, when the magnetic sensor 263 is attached to the bus bar holder 240, a portion of the first conductive wire 264 is bent toward the other orthogonal direction side (-X side). The first conductive wire 264 has a first connection portion 264a, a first inclined portion 264b, and a first terminal portion 264c. The first connection portion 264a is a portion connected to the magnetic sensor 263. The first connection portion 264a is located inside the magnetic sensor accommodating hole 240d. The first connection portion 264a extends upward from the magnetic sensor 263. A lower end of the first connection portion 264a is connected to the magnetic sensor 263 and is electrically connected to the magnetic sensor 263. An upper end of the first connecting portion 264a is located between the magnetic sensor 263 and the first inclined surface 240e in the axial direction. The first connecting portion 264a is disposed so as to overlap with the first inclined surface 240e when viewed in the axial direction.

[0066] The first inclined portion 264b extends upward from the upper end of the first connecting portion 264a toward the other diagonal orthogonal direction side (-X side). The first inclined portion 264b is positioned upward as it extends toward the other orthogonal direction side. The end of the first inclined portion 264b on the other orthogonal direction side is positioned below the first through-hole 240a.

[0067] The first terminal portion 264c extends upward from an end portion of the first inclined portion 264b on the other orthogonal direction side (-X side). The first terminal portion 264c is located on the other orthogonal direction side of the first connecting portion 264a. The first terminal portion 264c is axially passed through the first through hole 240a. The first terminal portion 264c protrudes upward from the bus bar holder 240 through the first through hole 240a. An upper end portion of the first terminal portion 264c protrudes upward from the circuit board 270 through a first opening 270a provided in the circuit board 270. The portion of the first terminal portion 264c that passes through the first opening 270a of the circuit board 270 is electrically connected to the circuit board 270 by solder 280.

[0068] In this embodiment, the second conductive wire 265 is formed by bending a portion of a conductive wire extending linearly in the axial direction to one side in the orthogonal direction (the +X side). In this embodiment, when the magnetic sensor 263 is attached to the bus bar holder 240, the portion of the second conductive wire 265 is bent to one side in the orthogonal direction (the +X side). The second conductive wire 265 has a second connection portion 265a, a second inclined portion 265b, and a second terminal portion 265c. The second connection portion 265a is a portion connected to the magnetic sensor 263. The second connection portion 265a is located inside the magnetic sensor accommodating hole 240d. The second connection portion 265a extends upward from the magnetic sensor 263. A lower end of the second connection portion 265a is connected to the magnetic sensor 263 and is electrically connected to the magnetic sensor 263. An upper end of the second connecting portion 265a is located between the magnetic sensor 263 and the second inclined surface 240f in the axial direction. The second connecting portion 265a is disposed so as to overlap with the second inclined surface 240f when viewed in the axial direction.

[0069] The second inclined portion 265b extends upward from the upper end of the second connection portion 265a toward one diagonal orthogonal direction (+X side). The second inclined portion 265b is positioned upward as it extends toward one orthogonal direction side. The end of the second inclined portion 265b on the one orthogonal direction side is positioned below the second through-hole 240b.

[0070] The second terminal portion 265c extends upward from an end portion of the second inclined portion 265b on one orthogonal direction side (+X side). The second terminal portion 265c is located on one orthogonal direction side of the second connecting portion 265a. The second terminal portion 265c is axially passed through the second through hole 240b. The second terminal portion 265c protrudes upward from the bus bar holder 240 through the second through hole 240b. An upper end portion of the second terminal portion 265c protrudes upward from the circuit board 270 through a second opening 270b provided in the circuit board 270. The portion of the second terminal portion 265c that passes through the second opening 270b of the circuit board 270 is electrically connected to the circuit board 270 by solder 280.

[0071] Unlike the first conductive wire 264 and the second conductive wire 265, the third conductive wire 266 extends linearly in the axial direction. The third conductive wire 266 has a third connection portion 266a and a third terminal portion 266c. The third connection portion 266a is a portion that connects to the magnetic sensor 263. The third connection portion 266a is located inside the magnetic sensor accommodating hole 240d. The third connection portion 266a extends upward from the magnetic sensor 263. A lower end of the third connection portion 266a connects to the magnetic sensor 263 and is electrically connected to the magnetic sensor 263. An upper end of the third connection portion 266a is located below the third through-hole 240c.

[0072] The third terminal 266c extends upward from the upper end of the third connection portion 266a. The third connection portion 266a and the third terminal 266c are connected in a straight line in the axial direction. The third terminal 266c is passed through the third through-hole 240c in the axial direction. The third terminal 266c protrudes upward from the bus bar holder 240 through the third through-hole 240c. The upper end of the third terminal 266c protrudes upward from the circuit board 270 through a third opening 270c provided in the circuit board 270. The portion of the third terminal 266c that passes through the third opening 270c of the circuit board 270 is electrically connected to the circuit board 270 by solder 280.

[0073] In the circuit board 270 of this embodiment, the first opening 270a, the second opening 270b, and the third opening 270c are spaced apart in the orthogonal direction. In this embodiment, the inner diameters of the first opening 270a, the second opening 270b, and the third opening 270c are larger than the inner diameters of the first through hole 240a, the second through hole 240b, and the third through hole 240c, respectively. The first opening 270a overlaps with the first through hole 240a when viewed in the axial direction. The second opening 270b overlaps with the second through hole 240b when viewed in the axial direction. The third opening 270c overlaps with the third through hole 240c when viewed in the axial direction. As described above, the first conductive wire 264, the second conductive wire 265, and the third conductive wire 266 are passed through the first opening 270a, the second opening 270b, and the third opening 270c, respectively.

[0074] Next, a procedure for attaching the magnetic sensor 263 to the bus bar holder 240 in this embodiment will be described. As shown in FIG. 6 , before attaching the magnetic sensor 263 to the bus bar holder 240, the first conductive wire 264, the second conductive wire 265, and the third conductive wire 266 each extend linearly straight upward from the magnetic sensor 263. When the first conductive wire 264, the second conductive wire 265, and the third conductive wire 266 extending linearly from the lower side of the bus bar holder 240 are inserted into the magnetic sensor accommodating hole 240d, the upper end of the first conductive wire 264 contacts the first inclined surface 240e, and the upper end of the second conductive wire 265 contacts the second inclined surface 240f. At this time, the upper end of the first conductive wire 264 is guided along the first inclined surface 240e to the first through hole 240a and inserted into the first through hole 240a. The upper end of second conductive wire 265 is guided along second inclined surface 240f to second through hole 240b and inserted into second through hole 240b. At this time, a portion of first conductive wire 264 and a portion of second conductive wire 265, which had been extending linearly in the axial direction, are deformed so as to move away from each other in the perpendicular direction. Unlike first conductive wire 264 and second conductive wire 265, the upper end of third conductive wire 266 is inserted into third through hole 240c without being deformed in the perpendicular direction. Furthermore, when first conductive wire 264, second conductive wire 265, and third conductive wire 266 are inserted into magnetic sensor accommodating hole 240d, first conductive wire 264, second conductive wire 265, and third conductive wire 266 protrude upward from bus bar holder 240 via first through hole 240a, second through hole 240b, and third through hole 240c, respectively. At this time, a portion of first conductive wire 264 and a portion of second conductive wire 265 are bent orthogonally by first inclined surface 240e or second inclined surface 240f and deformed. When magnetic sensor 263 is inserted into magnetic sensor accommodating hole 240d, the upward-facing surface of magnetic sensor 263 comes into contact with first support surface 240g and second support surface 240h, and magnetic sensor 263 is positioned in the axial direction relative to bus bar holder 240. When magnetic sensor 263 is inserted into magnetic sensor accommodating hole 240d until magnetic sensor 263 is positioned in the axial direction relative to bus bar holder 240, first conductive wire 264 and second conductive wire 265 assume the shape shown in FIG.

[0075] Therefore, in this embodiment, by the process of inserting the first conductive wire 264, the second conductive wire 265, the third conductive wire 266, and the magnetic sensor 263 into the magnetic sensor accommodating hole 240d, the first conductive wire 264 and the second conductive wire 265, which extend in a straight line straight upward from the magnetic sensor 263, are guided by the first inclined surface 240e and the second inclined surface 240f to the first through hole 240a and the second through hole 240b, respectively, and can be easily passed through the first through hole 240a and the second through hole 240b.

[0076] According to the present embodiment, the bus bar holder 240 has a magnetic sensor accommodating hole 240d that accommodates the magnetic sensor 263, a first through hole 240a and a second through hole 240b that extend upward from the magnetic sensor accommodating hole 240d and open upward, and a first inclined surface 240e and a second inclined surface 240f that are provided on the inner surface on the upper side of the magnetic sensor accommodating hole 240d. An end of the first inclined surface 240e that is farther from the second inclined surface 240f in the orthogonal direction is connected to a lower end of the first through hole 240a, and an end of the first inclined surface 240e that is closer to the second inclined surface 240f in the orthogonal direction is positioned closer to the second inclined surface 240f in the orthogonal direction than the first connecting portion 264a. Furthermore, the end of second inclined surface 240f farther from first inclined surface 240e in the orthogonal direction is connected to the lower end of second through-hole 240b, and the end of second inclined surface 240f closer to first inclined surface 240e in the orthogonal direction is positioned closer to first inclined surface 240e in the orthogonal direction than second connecting portion 265a. Therefore, by inserting first conductive wire 264 into first through-hole 240a along first inclined surface 240e and inserting second conductive wire 265 into second through-hole 240b along second inclined surface 240f, the orthogonal distance between first terminal portion 264c and second terminal portion 265c can be made larger than the orthogonal distance between first connecting portion 264a and second connecting portion 265a. This allows the orthogonal distance between multiple conductive wires to be larger in the portion connected to circuit board 270. In this embodiment, the orthogonal spacing between the first terminal portion 264c and the third terminal portion 266c and the orthogonal spacing between the second terminal portion 265c and the third terminal portion 266c can be increased. Therefore, the spacing between the positions where the circuit board 270 and each conductive wire are connected by soldering can be increased. This facilitates the process of connecting the circuit board 270 and each conductive wire by soldering. This allows the circuit board 270 and each conductive wire to be easily soldered together even when the soldering process is performed using a soldering device with relatively low operational precision. Therefore, there is no need to use a soldering device with high operational precision in the soldering process. Therefore, the circuit board 270 and each conductive wire can be electrically connected using a relatively inexpensive, general-purpose soldering device.Therefore, the manufacturing cost of the electric actuator 210 can be reduced.

[0077] According to the present embodiment, the end of first inclined surface 240e closer to second inclined surface 240f in the orthogonal direction is disposed closer to second inclined surface 240f in the orthogonal direction than first connecting portion 264a. The end of second inclined surface 240f closer to first inclined surface 240e in the orthogonal direction is disposed closer to first inclined surface 240e in the orthogonal direction than second connecting portion 265a. Therefore, in the step of inserting each conductive wire and magnetic sensor 263 into magnetic sensor accommodating hole 240d, the upper end of first conductive wire 264 extending linearly straight upward from magnetic sensor 263 can easily come into contact with first inclined surface 240e, and the upper end of second conductive wire 265 extending linearly straight upward from magnetic sensor 263 can easily come into contact with second inclined surface 240f. At this time, the upper end of first conductive wire 264 is guided along first inclined surface 240e to first through hole 240a and inserted into first through hole 240a. The upper end of second conductive wire 265 is guided along second inclined surface 240f to second through hole 240b and inserted into second through hole 240b. Therefore, even when first conductive wire 264 and second conductive wire 265 are provided so as to extend linearly straight upward from magnetic sensor 263, a portion of first conductive wire 264 and a portion of second conductive wire 265 can be easily deformed so as to move away from each other in the orthogonal direction. In other words, by attaching magnetic sensor 263 to bus bar holder 240, the orthogonal spacing between the terminals of each conductive wire connected to circuit board 270 can be increased. Therefore, there is no need to use pre-bent first conductive wires 264 and second conductive wires 265 in order to pass the first conductive wires 264 and second conductive wires 265 through the first through hole 240a and the second through hole 240b. This reduces the manufacturing cost and number of manufacturing steps for the conductive wires. Furthermore, in this embodiment, no additional process is required to pass the first conductive wire 264 and the second conductive wire 265 through the first through hole 240a and the second through hole 240b, respectively. This improves the workability of assembling the conductive wires and the magnetic sensor 263 to the bus bar holder 240. This reduces the number of manufacturing steps for the electric actuator 210.

[0078] In this embodiment, the number of conductive wires connected to magnetic sensor 263 is not limited to three. For example, third conductive wire 266 may not be provided, or four or more conductive wires may be provided. Furthermore, the number of through holes and the number of inclined surfaces provided in bus bar holder 240 are not limited to three, respectively, and an appropriate number of through holes and inclined surfaces can be provided depending on the number of conductive wires connected to magnetic sensor 263, the positions of each connection portion and the openings provided in the substrate, and the like.

[0079] The electric actuator to which the present invention is applied may be any device that can move an object when supplied with electric power, and may be a motor without a reduction mechanism. The electric actuator may also be an electric pump that includes a pump unit driven by a motor unit. The application of the electric actuator is not particularly limited. The electric actuator may be mounted in a shift-by-wire type actuator device that is driven based on the driver's shift operation. The electric actuator may also be mounted in equipment other than a vehicle. The configurations described in this specification may be combined as appropriate within the scope of not being mutually contradictory. [Explanation of symbols]

[0080] 10,210...electric actuator, 11...case, 12...support surface, 15...support member (partition member), 20...motor portion, 21...motor shaft, 21a...first shaft portion, 21b...second shaft portion (eccentric shaft portion), 22...rotor, 23...stator, 24b...outer surface, 25...through hole, 26...recessed portion, 30...reduction mechanism, 40...magnet, 41...output shaft, 42...connecting portion, 44...cylindrical portion, 45...connecting recess, 51...second bearing, 52...third bearing, 53...first bearing, 63,263...magnetic sensor, 64...conductive wire, 70,270...circuit board, 140,240...bus bar holder, 141...peripheral wall portion, 142...projection portion, 143...spacer, 150...bus bar, 240a...first through hole, 240b...second through hole, 240e...first inclined surface, 240f...second inclined surface, 240d...magnetic sensor accommodating hole, 264...first conductive wire, 264a...first connecting portion, 264c...first terminal portion, 265...second conductive wire, 265a...second connecting portion, 265c...second terminal portion, J1...central axis, J2...eccentric axis

Claims

1. a motor section including a rotor rotatable about a central axis extending in the axial direction and a stator radially opposed to the rotor with a gap therebetween; a magnet fixed to the rotor; a bus bar electrically connected to the motor unit; a bus bar holder disposed on one axial side of the rotor and configured to hold the bus bar; a magnetic sensor fixed to the bus bar holder and capable of detecting a magnetic field of the magnet; a conductive wire electrically connected to the magnetic sensor; a circuit board disposed on one axial side of the bus bar holder and electrically connected to the motor unit; Equipped with the magnetic sensor is disposed on one side of the magnet in the axial direction, facing the magnet with a gap therebetween; The conductive wire passes through the bus bar holder from inside the bus bar holder and is electrically connected to the circuit board.

2. The electric actuator according to claim 1 , wherein the magnetic sensor and the bus bar holder are formed into an integrated molded body by resin molding.

3. The conductive wires are provided in plurality, the plurality of conductive wires include a first conductive wire and a second conductive wire extending from the magnetic sensor to one side in the axial direction; the first conductive wire and the second conductive wire are arranged at an interval in an orthogonal direction perpendicular to the axial direction, The bus bar holder includes: a magnetic sensor accommodating hole that opens to the other axial side and accommodates the magnetic sensor; a first through hole and a second through hole extending from the magnetic sensor receiving hole to one side in the axial direction and opening to the one side in the axial direction; a first inclined surface and a second inclined surface provided on an inner surface on one axial side of the magnetic sensor accommodating hole, the first through hole and the second through hole are arranged at an interval in the orthogonal direction, the first inclined surface and the second inclined surface are disposed at an interval in the orthogonal direction, and are positioned toward one axial side as they move away from each other in the orthogonal direction; an end portion of the first inclined surface that is farther from the second inclined surface in the orthogonal direction is connected to an end portion of the first through hole on the other axial side; an end portion of the second inclined surface that is farther from the first inclined surface in the orthogonal direction is connected to an end portion of the second through hole on the other axial side; The first conductive line is a first terminal portion passed through the first through hole; a first connection portion connected to the magnetic sensor and overlapping with the first inclined surface when viewed in the axial direction; and The second conductive line is a second terminal portion passed through the second through hole; a second connection portion connected to the magnetic sensor and overlapping with the second inclined surface when viewed in the axial direction; and an end portion of the first inclined surface that is closer to the second inclined surface in the orthogonal direction is disposed closer to the second inclined surface in the orthogonal direction than the first connection portion; The electric actuator according to claim 1, wherein an end of the second inclined surface closer to the first inclined surface in the perpendicular direction is positioned closer to the first inclined surface in the perpendicular direction than the second connection portion.

4. The outer peripheral surface of the stator is provided with a plurality of grooves recessed radially inward at intervals in the circumferential direction and extending in the axial direction, the bus bar holder has a peripheral wall portion that extends toward the other axial side at a position radially outward from an outer circumferential surface of the stator and faces the groove portion, The peripheral wall portion has a protrusion portion that protrudes radially inward and is inserted into the groove portion. The electric actuator according to any one of claims 1 to 3.

5. a case having a support surface facing one axial direction and accommodating the motor unit; the bus bar holder has a spacer protruding to one side in the axial direction, The other axial side of the circuit board is in contact with the spacer, The electric actuator according to claim 4 , wherein the bus bar holder and the circuit board are screwed to the support surface from one axial side at positions overlapping with the spacer when viewed in the axial direction.

6. a support member supported by the case from the other side in the axial direction, the support member contacts the other axial side of the stator, The electric actuator according to claim 5 , wherein the other axial end of the peripheral wall portion contacts one axial side of the stator when the bus bar holder is screwed to the support surface.

7. The electric actuator according to claim 1 , wherein the magnetic sensor is a Hall element.

Images