Electric actuator

Abstract

To provide an electric actuator that can prevent its structure from being complicated.SOLUTION: An actuator 100 comprises a motor unit 40, a transmission mechanism unit 50, a linear motion unit 60 that is connected to the transmission mechanism unit and moved linearly by the transmission mechanism unit, a case 10 that stores therein the motor unit, the transmission mechanism unit, and the linear motion unit, a board 70 having an inverter circuit that supplies power to the motor unit, a magnet 80 provided in the linear motion unit, and a magnetic sensor 71 that can detect the magnetic field of a magnet. The magnetic sensor has a sensor body unit 72 arranged apart from the board and an edge unit 73 extending from the sensor body unit and fixed to the board. The case has a holding recession unit 30 that holds the sensor main unit. The holding recession unit opens toward the board.SELECTED DRAWING: Figure 2

Description

[Technical field]

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

[0002] 2. Description of the Related Art Conventionally, in a device that converts the driving force of an electric motor into linear motion and outputs the linear motion, a structure is known in which the amount of movement of a member that is caused to move linearly is detected by a stroke sensor (eg, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-114398 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned device, in order to ensure the detection accuracy of the stroke sensor, it is preferable to place the stroke sensor accurately near the member that can be linearly moved. However, simply placing the stroke sensor close to the member may complicate the structure of the device.

[0005] In view of the above circumstances, one object of the present invention is to provide an electric actuator that can prevent the structure from becoming complicated. [Means for solving the problem]

[0006] One aspect of the electric actuator of the present invention includes a motor section, a transmission mechanism section connected to the motor section, a linear motion section connected to the transmission mechanism section and linearly moved by the transmission mechanism section, a case that houses the motor section, the transmission mechanism section, and the linear motion section, a substrate having an inverter circuit that supplies power to the motor section, a magnet provided on the linear motion section, and a magnetic sensor capable of detecting the magnetic field of the magnet. The magnetic sensor has a sensor main body section that is disposed away from the substrate, and a terminal section that extends from the sensor main body section and is fixed to the substrate. The case has a holding recess that holds the sensor main body section. The holding recess is open toward the substrate. Effect of the Invention

[0007] According to one aspect of the present invention, the structure of the electric actuator can be prevented from becoming complicated. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing an electric actuator according to one embodiment. [Diagram 2] FIG. 2 is a perspective view showing a part of the electric actuator in one embodiment. [Diagram 3] FIG. 3 is a perspective view showing a case in one embodiment. [Figure 4] FIG. 4 is a top view of a portion of the electric actuator according to one embodiment. [Diagram 5] FIG. 5 is a cross-sectional view showing the electric actuator in one embodiment, taken along line VV of FIG. [Figure 6] FIG. 6 is a cross-sectional view showing the electric actuator in one embodiment, taken along line VI-VI in FIG. [Figure 7] FIG. 7 is a cross-sectional perspective view showing a part of the electric actuator in one embodiment. [Figure 8] FIG. 8 is a perspective view showing a part of an electric actuator in one modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Each figure shows a virtual central axis J1 in the motor unit of the electric actuator of the embodiment described below. In the following description, the axial direction of the central axis J1 is simply called the "axial direction". The radial direction centered on the central axis J1 is simply called the "radial direction". The X-axis shown in each figure indicates the direction in which the central axis J1 extends. The Y-axis shown in each figure indicates one direction perpendicular to the X-axis direction. The Z-axis shown in each figure indicates a direction perpendicular to both the X-axis direction and the Y-axis direction. In the following description, the direction along the Y-axis is called the "width direction", and the direction along the Z-axis is called the "up-down direction". In addition, the side of the axial direction toward which the X-axis arrow points (+X side) is called the "one axial direction side", and the opposite side of the axial direction toward which the X-axis arrow points (-X side) is called the "other axial direction side". The side in the width direction where the Y-axis arrow points (+Y side) is called "one side in the width direction," and the side opposite the side in the axial direction where the Y-axis arrow points (-Y side) is called "the other side in the width direction." The side in the up-down direction where the Z-axis arrow points (+Z side) is called "upper side," and the side opposite the side in the up-down direction where the Z-axis arrow points (-Z side) is called "lower side."

[0010] In the following embodiments, the width direction (Y-axis direction) corresponds to the "first direction" intersecting with the axial direction. The up-down direction (Z-axis direction) corresponds to the "second direction" intersecting with both the axial direction and the first direction. The upper side corresponds to "one side of the second direction." Note that the up-down direction, width direction, upper side, and lower side are names simply for explaining the relative positional relationship of each part, and the actual positional relationship, etc. may be a positional relationship, etc. other than the positional relationship, etc. indicated by these names.

[0011] The electric actuator 100 of this embodiment shown in Fig. 1 is a linear actuator that moves a driven object in the axial direction. The electric actuator 100 is mounted on, for example, a vehicle. As shown in Fig. 2, the electric actuator 100 of this embodiment includes a case 10, a motor unit 40, a transmission mechanism unit 50, a linear motion unit 60, a substrate 70, a magnet 80, and a magnetic sensor 71.

[0012] The case 10 accommodates the motor section 40, the transmission mechanism section 50, the linear motion section 60, the substrate 70, the magnet 80, and the magnetic sensor 71 inside. In this specification, the phrase "a certain part accommodates a certain object inside" means that at least a part of the certain object is located inside the certain part. In this embodiment, the case 10 is made of a non-magnetic material. The case 10 is made of, for example, resin.

[0013] As shown in FIG. 1, the case 10 has a first case member 11 and a second case member 12. The first case member 11 has a case main body 13, a flange 14, and a connector 15. As shown in FIG. 3, the case main body 13 is box-shaped and opens upward. The case main body 13 has a first housing section 21 that houses the motor section 40 therein, a second housing section 22 that houses the transmission mechanism section 50 therein, and a third housing section 23 that houses a part of the linear motion section 60 and the magnet 80 therein. The insides of the first housing section 21, the second housing section 22, and the third housing section 23 are open upward.

[0014] As shown in Fig. 4, the first housing section 21 and the third housing section 23 are arranged side by side in the width direction (Y-axis direction). The inside of the first housing section 21 and the inside of the third housing section 23 are connected to each other. The first housing section 21 and the third housing section 23 form a housing section 29 that houses the motor section 40 and the linear motion section 60 therein. The housing section 29 has an opening 29a that opens upward. The opening 29a is formed by an upper opening of the first housing section 21 and an upper opening of the third housing section 23.

[0015] The second housing portion 22 is located on the other axial side (-X side) of the first housing portion 21 and the third housing portion 23. A first partition wall portion 24 is provided between the first housing portion 21 and the second housing portion 22 in the axial direction. The first partition wall portion 24 is provided with a through hole 24a that passes through the first partition wall portion 24 in the axial direction. The interior of the first housing portion 21 and the interior of the second housing portion 22 are connected to each other via the through hole 24a. The through hole 24a opens upward.

[0016] A second partition wall portion 25 is provided between the second housing portion 22 and the third housing portion 23 in the axial direction. The second partition wall portion 25 is located on one axial side (+X side) of the first partition wall portion 24. As shown in FIG. 3, the second partition wall portion 25 is provided with a through hole 25a that passes through the second partition wall portion 25 in the axial direction. The interior of the second housing portion 22 and the interior of the third housing portion 23 are connected to each other via the through hole 25a. The through hole 25a has a circular shape centered on the output axis J2 when viewed in the axial direction.

[0017] The output axis J2 is an imaginary line extending in the direction in which the linear motion part 60 moves. In this embodiment, the output axis J2 extends parallel to the central axis J1 of the motor part 40. That is, in this embodiment, the linear motion part 60 moves linearly in the axial direction of the motor part 40. As shown in Figs. 4 and 5, in this embodiment, the output axis J2 is located on the other widthwise side (-Y side) of the central axis J1. As shown in Fig. 6, in this embodiment, the vertical position of the output axis J2 is the same as the vertical position of the central axis J1.

[0018] As shown in FIG. 4, the second housing portion 22 has a gear housing portion 27 and a tube housing portion 28. The gear housing portion 27 extends in the width direction (Y-axis direction) when viewed in the vertical direction. A portion of the gear housing portion 27 on one side in the width direction (+Y side) is connected to the inside of the first housing portion 21 via the through hole 24a. The tube housing portion 28 extends in the axial direction (X-axis direction) when viewed in the vertical direction. The gear housing portion 27 and the tube housing portion 28 intersect with each other. The tube housing portion 28 has a portion located on one axial side (+X side) of the gear housing portion 27 and a portion located on the other axial side (-X side) of the gear housing portion 27. A portion of the tube housing portion 28 located on one axial side of the gear housing portion 27 is connected to the inside of the third housing portion 23 via the through hole 25a.

[0019] As shown in FIG. 3, a seal retaining portion 26 is provided on a wall portion on one axial side (+X side) of the case body 13. The seal retaining portion 26 is cylindrical and protrudes from the case body 13 on one axial side. The seal retaining portion 26 is cylindrical and has an opening on both axial sides centered on the output axis J2. The opening on the other axial side (-X side) of the seal retaining portion 26 is connected to the inside of the third housing portion 23. The outside and the inside of the case 10 are connected to each other through the inside of the seal retaining portion 26. As shown in FIG. 5, an annular seal member 18 that surrounds the output axis J2 is held inside the seal retaining portion 26. The seal member 18 is, for example, an oil seal.

[0020] As shown in FIG. 3, the flange portion 14 spreads from the upper end of the case body 13 in a direction perpendicular to the up-down direction. The outer edge of the flange portion 14 has a generally rectangular shape that is long in the axial direction when viewed in the up-down direction. A board support portion 16 is provided on the upper surface of the flange portion 14. The board support portion 16 protrudes upward from the upper surface of the flange portion 14. The board support portion 16 is cylindrical and opens upward. A plurality of board support portions 16 are provided. In this embodiment, two pairs of board support portions 16 are provided with an axial gap therebetween, each pair being arranged to sandwich the opening 29a in the width direction (Y-axis direction).

[0021] The connector portion 15 extends downward from the case body portion 13. An external device such as a power supply device is connected to the connector portion 15. The connector portion 15 holds a plurality of wiring members 17 shown in FIG. 2. The plurality of wiring members 17 extend upward from the connector portion 15. The plurality of wiring members 17 pass through the inside of the first housing portion 21 and are electrically connected to the board 70.

[0022] As shown in Fig. 1, the second case member 12 is located above the first case member 11. The second case member 12 is fixed to the first case member 11. As shown in Fig. 6, the second case member 12 is in the shape of a substantially rectangular parallelepiped box that opens downward. The lower end of the second case member 12 contacts the outer edge of the flange portion 14 from above. The board support portion 16 and the board 70 are housed inside the second case member 12.

[0023] As shown in FIG. 2, the case 10 has a holding recess 30. The holding recess 30 holds a sensor body 72 (described later) of the magnetic sensor 71. In this embodiment, the holding recess 30 is provided in a side wall 23a located on the other widthwise side (-Y side) of the walls constituting the third housing section 23. In this embodiment, the side wall 23a is a wall portion of the case 10 facing the linear motion portion 60 with a gap in the widthwise direction (Y-axis direction). In this embodiment, the holding recess 30 is a hole portion recessed downward from the upper end face of the side wall 23a and having a bottom on the lower side. The holding recess 30 has a rectangular shape that is long in the axial direction (X-axis direction) when viewed in the vertical direction. The holding recess 30 is located axially between two board support portions 16 located on the other widthwise side of the opening 29a when viewed in the vertical direction.

[0024] As shown in Fig. 5, the motor section 40 is accommodated inside the first accommodation section 21. The motor section 40 has a rotor 41 that is rotatable about a central axis J1, a stator 42 located radially outside the rotor 41, and a housing 45 that accommodates the rotor 41 and the stator 42 inside. The rotor 41 has a shaft 43 that extends in the axial direction, and a rotor body 44 fixed to the shaft 43. Although not shown, the rotor body 44 has a rotor core and a rotor magnet.

[0025] The shaft 43 is cylindrical and extends in the axial direction around the central axis J1. The shaft 43 protrudes from the inside of the housing 45 toward the other axial side (-X side). The part of the shaft 43 that protrudes from the housing 45 toward the other axial side is the output part 43a that protrudes in the axial direction. That is, the motor part 40 has the output part 43a. In this embodiment, the output part 43a protrudes toward the other axial side (-X direction) in the axial direction of the motor part 40. The output part 43a is axially inserted into the through hole 24a. The end of the output part 43a on the other axial side is located in the gear housing part 27 of the second housing part 22. The stator 42 is electrically connected to the substrate 70 via a plurality of bus bars 19 shown in FIG. 2. In FIG. 5, only the output part 43a of the motor part 40 is shown in cross section.

[0026] The transmission mechanism 50 is connected to the motor unit 40. The transmission mechanism 50 converts the rotational motion of the rotor 41 in the motor unit 40 into linear motion and transmits the linear motion to the linear motion unit 60. As shown in Fig. 5, in this embodiment, the transmission mechanism 50 has a first gear 51, a second gear 52, and a cylindrical member 53. The first gear 51 and the second gear 52 are housed inside the gear housing portion 27.

[0027] The first gear 51 is fixed to the motor unit 40. More specifically, the first gear 51 is fixed to a portion of the output unit 43a that is located inside the gear housing unit 27. As a result, the output unit 43a is connected to the transmission mechanism unit 50. The first gear 51 rotates around the central axis J1 as the shaft 43 rotates around the central axis J1. The second gear 52 is located on the other widthwise side (-Y side) of the first gear 51. The outer diameter of the second gear 52 is larger than the outer diameter of the first gear 51. The second gear 52 meshes with the first gear 51. As the first gear 51 rotates around the central axis J1, the second gear 52 that meshes with the first gear 51 rotates around the output axis J2. As shown in FIG. 2, an upper end of the second gear 52 protrudes upward from the inside of the gear housing unit 27. An upper end portion of the second gear 52 is located inside the second case member 12 .

[0028] As shown in FIG. 5, the tubular member 53 is cylindrical and extends in the axial direction. In this embodiment, the tubular member 53 is cylindrical and centered on the output axis J2 and opens to one axial side (+X side). The tubular member 53 is accommodated inside the tube accommodating portion 28. The tubular member 53 is supported by the inner surface of the tube accommodating portion 28 so as to be rotatable around the output axis J2. A threaded portion 54 is provided on the inner circumferential surface of the tubular member 53. The second gear 52 is connected to the outer circumferential surface of the tubular member 53. In this embodiment, the second gear 52 and the tubular member 53 are part of a single member. The tubular member 53 rotates around the output axis J2 as the second gear 52 rotates around the output axis J2. Since the outer diameter of the second gear 52 is larger than the outer diameter of the first gear 51, the rotation of the rotor 41 is transmitted to the second gear 52 and the tubular member 53 at a reduced speed.

[0029] The linear motion part 60 is connected to the transmission mechanism part 50. The linear motion part 60 is linearly moved by the transmission mechanism part 50. In this embodiment, the linear motion part 60 moves linearly in the axial direction of the motor part 40. FIG. 5 shows a state in which the linear motion part 60 is located furthest on the other axial side (-X side). In the following description, unless otherwise specified, the relative positional relationship of the linear motion part 60 will be described for the case in which the linear motion part 60 is located furthest on the other axial side.

[0030] The linear motion part 60 extends in the axial direction. In this embodiment, the linear motion part 60 extends from the transmission mechanism part 50 toward one axial side (+X direction). That is, in this embodiment, the linear motion part 60 extends from the transmission mechanism part 50 in the opposite direction to the direction in which the output part 43a protrudes in the axial direction of the motor part 40. As a result, by disposing the transmission mechanism part 50 on the other axial side (-X side) with respect to the motor part 40 and the linear motion part 60, it is possible to easily connect the motor part 40 and the linear motion part 60 to each other via the transmission mechanism part 50.

[0031] The linear motion part 60 is located on one axial side (+X side) of the transmission mechanism part 50. An end part of the linear motion part 60 on the other axial side (-X side) is connected to the transmission mechanism part 50. The linear motion part 60 is located on the other widthwise side (-Y side) of the motor part 40. In this embodiment, the motor part 40 and the linear motion part 60 are arranged side by side in the widthwise direction (Y-axis direction) intersecting the axial direction of the motor part 40. Therefore, the electric actuator 100 can be made smaller in size in the axial direction compared to a case where the motor part 40 and the linear motion part 60 are arranged side by side in the axial direction, for example.

[0032] The linear motion part 60 has a linear motion part main body 61 and a connected member 62. The linear motion part main body 61 has a base part 63, a connection part 64, and a flange part 65. The base part 63 extends in the axial direction. The base part 63 is cylindrical with the output axis J2 as its center. The base part 63 is accommodated inside the third accommodation part 23. An end part on one axial side (+X side) of the base part 63 protrudes to the outside of the case 10 through the inside of the seal holding part 26. The seal member 18 is in contact with the outer peripheral surface of the base part 63. The seal member 18 seals the space between the linear motion part 60 and the case 10.

[0033] The connection portion 64 is connected to the other axial side (-X side) of the base portion 63. The connection portion 64 extends in the axial direction. The connection portion 64 is substantially cylindrical and centered on the output axis J2. The outer diameter of the connection portion 64 is smaller than the outer diameter of the base portion 63. The connection portion 64 is passed through the through hole 25a in the axial direction. At least a part of the connection portion 64 is located inside the tubular member 53. More specifically, the entire connection portion 64, except for the end portion on one axial side (+X side), is located inside the tubular member 53. The outer peripheral surface of the connection portion 64 is provided with a threaded portion 66 that meshes with the threaded portion 54 provided on the inner peripheral surface of the tubular member 53. The threaded portion 54 and the threaded portion 66 mesh with each other, so that the connection portion 64 is connected to the tubular member 53. As a result, the linear motion portion 60 is connected to the transmission mechanism portion 50. When the tubular member 53 rotates about the output axis J2, the threaded portion 66 of the connection portion 64 is fed in the axial direction by the threaded portion 54 rotating about the output axis J2. This causes the linear motion portion 60 to move in the axial direction.

[0034] The flange portion 65 is provided on the outer peripheral surface at the end portion on the other axial side (-X side) of the base portion 63. The flange portion 65 protrudes outward from the outer peripheral surface of the base portion 63 in a radial direction centered on the output axis J2. The flange portion 65 is annular and surrounds the base portion 63.

[0035] The connected member 62 is fixed to an end portion on one axial side (+X side) of the linear motion body 61. The end portion on one axial side of the linear motion body 61 is the end portion on one axial side of the base 63. A driven object that is moved in the axial direction by the electric actuator 100 is connected to the connected member 62. The connected member 62 is provided with a connecting hole 67 that passes through the connected member 62 in the vertical direction. A shaft or the like provided on the driven object is passed through the connecting hole 67 in the vertical direction.

[0036] The magnet 80 is provided in the linear motion section 60. In this embodiment, the magnet 80 is cylindrical with the output axis J2 at its center and open on both axial sides. The base 63 passes through the interior of the magnet 80 in the axial direction. The base 63 is fitted into the interior of the magnet 80. The inner peripheral surface of the magnet 80 is fixed to the outer peripheral surface of the base 63. The end of the magnet 80 on the other axial side (-X side) is in contact with the flange section 65. The magnet 80 is positioned in the axial direction by the flange section 65. The magnet 80 is accommodated inside the third accommodation section 23. The magnet 80 is a permanent magnet.

[0037] As shown in FIG. 2, the substrate 70 is a plate-like shape with a plate surface facing the up-down direction. In this embodiment, the substrate 70 extends in the width direction (Y-axis direction). More specifically, the substrate 70 is a substantially rectangular plate-like shape that is long in the width direction. The substrate 70 is located on the upper side of the first case member 11. The substrate 70 is fixed to a plurality of substrate support parts 16 by screw members 77. Each screw member 77 is passed axially from above into a hole provided in the substrate 70 and fastened to each substrate support part 16. An edge part on one width direction side (+Y side) of the substrate 70 is fixed to two substrate support parts 16 located on one width direction side of the opening 29a. An edge part on the other width direction side (-Y side) of the substrate 70 is fixed to two substrate support parts 16 located on the other width direction side of the opening 29a. The substrate 70 is disposed across the opening 29a in the width direction. The substrate 70 covers at least a part of the opening 29a from above. In this embodiment, the substrate 70 covers a part of the opening 29a from above. The substrate 70 is disposed above the motor section 40 and the linear motion section 60, straddling the motor section 40 and the linear motion section 60 in the width direction.

[0038] As shown in FIG. 4, the substrate 70 overlaps with the motor section 40 and the linear motion section 60 when viewed in the vertical direction. More specifically, the substrate 70 overlaps with a part of the motor section 40 and a part of the base section 63 when viewed in the vertical direction. The substrate 70 overlaps with the magnet 80 when viewed in the vertical direction. The substrate 70 is disposed at a position different from that of the first gear 51 and the second gear 52 when viewed in the vertical direction. The substrate 70 overlaps with an end portion on one axial side (+X side) of the cylindrical member 53 when viewed in the vertical direction. The substrate 70 overlaps with the holding recess 30 when viewed in the vertical direction. As shown in FIG. 7, the substrate 70 covers the upper opening of the holding recess 30 from above. As a result, the holding recess 30 opens toward the substrate 70. In this embodiment, the holding recess 30 is a hole portion that opens toward the substrate 70.

[0039] As shown in FIG. 6, the vertical distance L2 between the linear motion unit 60 and the substrate 70 is greater than the vertical distance L1 between the motor unit 40 and the substrate 70. The distance L1 shown in FIG. 6 is the vertical distance between the upper end of the motor unit 40 and the lower surface of the substrate 70. The distance L2 shown in FIG. 6 is the vertical distance between the upper end of the base 63 and the lower surface of the substrate 70. The substrate 70 has an inverter circuit 78 that supplies power to the motor unit 40. The inverter circuit 78 has, for example, a plurality of transistors. The inverter circuit 78 supplies power to the stator 42 via the bus bar 19.

[0040] The magnetic sensor 71 is a sensor capable of detecting the magnetic field of the magnet 80. The magnetic sensor 71 detects the strength of the magnetic field of the magnet 80, thereby enabling the detection of the axial position of the linear motion part 60. The magnetic sensor 71 is a so-called DIP (Dual In-line Package) type electronic component. The magnetic sensor 71 has a sensor body part 72 and a terminal part 73. The sensor body part 72 is a part capable of detecting the magnetic field of the magnet 80. As shown in FIG. 7, the sensor body part 72 is a substantially rectangular parallelepiped that is thin in the width direction (Y-axis direction). The dimension of the sensor body part 72 in the axial direction (X-axis direction) is larger than the dimension of the sensor body part 72 in the width direction. The sensor body part 72 is disposed away from the substrate 70 in the up-down direction. More specifically, the sensor body part 72 is disposed away from the substrate 70 on the lower side.

[0041] The sensor body 72 is held inside the holding recess 30. The sensor body 72 is fitted inside the holding recess 30. The lower surface of the sensor body 72 is in contact with the bottom surface located on the lower side of the inner surface of the holding recess 30. A gap may be provided between the bottom surface and the sensor body 72 in the up-down direction. As shown in FIG. 6, both side surfaces in the width direction (Y-axis direction) of the sensor body 72 are in contact with the side surfaces located on both sides in the width direction of the inner surface of the holding recess 30. A gap may be provided between the both side surfaces in the width direction of the sensor body 72 and the side surfaces located on both sides in the width direction of the inner surface of the holding recess 30. As shown in FIG. 7, the dimension of the sensor body 72 in the axial direction (X-axis direction) is smaller than the dimension of the holding recess 30 in the axial direction. Both side surfaces in the axial direction of the sensor body 72 are arranged away from both side surfaces in the axial direction of the inner surface of the holding recess 30. Both axial side surfaces of the sensor body 72 may be in contact with both axial side surfaces of the inner surface of the holding recess 30, respectively.

[0042] The terminal portion 73 extends upward from the sensor body 72 and is fixed to the substrate 70. The terminal portion 73 is passed through a through hole 70a that penetrates the substrate 70 in the vertical direction. The terminal portion 73 is electrically connected to the substrate 70 by, for example, solder. In this embodiment, a plurality of terminal portions 73 are provided. Three terminal portions 73 are provided, namely, a first terminal portion 74, a second terminal portion 75, and a third terminal portion 76. The first terminal portion 74, the second terminal portion 75, and the third terminal portion 76 are arranged side by side in the axial direction (X-axis direction). The second terminal portion 75 and the third terminal portion 76 are arranged to sandwich the first terminal portion 74 in the axial direction.

[0043] The first terminal portion 74 extends linearly in the vertical direction. The second terminal portion 75 is located on the other axial side (-X side) of the first terminal portion 74. The second terminal portion 75 has a first extension portion 75a extending upward from the sensor body portion 72, a second extension portion 75b extending upward and diagonally to the other axial side from an upper end portion of the first extension portion 75a, and a third extension portion 75c extending upward from an upper end portion of the second extension portion 75b. The first extension portion 75a and the second extension portion 75b are located inside the holding recess 30. The third extension portion 75c protrudes upward from the inside of the holding recess 30 and is connected to the substrate 70.

[0044] The third terminal portion 76 is located on one axial side (+X side) of the first terminal portion 74. The third terminal portion 76 has a first extension portion 76a extending upward from the sensor body portion 72, a second extension portion 76b extending upward and diagonally to one axial side from an upper end portion of the first extension portion 76a, and a third extension portion 76c extending upward from an upper end portion of the second extension portion 76b. The first extension portion 76a and the second extension portion 76b are located inside the holding recess 30. The third extension portion 76c protrudes upward from the inside of the holding recess 30 and is connected to the substrate 70.

[0045] The axial distance from the surface on the other axial side (-X side) of the third extension portion 75c to the surface on one axial side (+X side) of the third extension portion 76c is the same as the axial dimension of the holding recess 30. The third extension portion 75c and the third extension portion 76c are in contact with both axial side surfaces of the inner surface of the holding recess 30. Note that gaps may be provided between the third extension portions 75c, 76c and both axial side surfaces of the holding recess 30.

[0046] In FIG. 4, the state where the linear motion part 60 is positioned furthest on the other axial side (−X side) is indicated by a solid line, and the state where the linear motion part 60 is positioned furthest on one axial side (+X side) is indicated by a two-dot chain line. As shown in FIG. 4, when the linear motion part 60 is positioned furthest on the other axial side, the magnet 80 is positioned on the other axial side of the magnetic sensor 71. When the linear motion part 60 is positioned furthest on the other axial side, the magnet 80 faces the motor part 40 in the width direction (Y-axis direction) with a gap therebetween. When the linear motion part 60 is positioned furthest on the one axial side, the magnet 80 is positioned on the one axial side of the magnetic sensor 71. When the linear motion part 60 is positioned furthest on the one axial side, the magnet 80 is positioned on the one axial side of the motor part 40.

[0047] According to this embodiment, the magnetic sensor 71 has a sensor body 72 arranged away from the substrate 70 having the inverter circuit 78, and a terminal portion 73 extending from the sensor body 72 and fixed to the substrate 70. The case 10 has a holding recess 30 for holding the sensor body 72. The holding recess 30 opens toward the substrate 70. Therefore, when a worker or the like who manufactures the electric actuator 100 arranges the substrate 70 with the magnetic sensor 71 attached thereto, the worker or the like can insert the sensor body 72 arranged away from the substrate 70 into the holding recess 30 through the opening of the holding recess 30. This allows the worker or the like to easily hold the sensor body 72 in the holding recess 30 by arranging the substrate 70, and the sensor body 72 can be positioned easily and precisely. Therefore, even if the substrate 70 is arranged away from the linear motion portion 60, the sensor body 72 can be arranged near the linear motion portion 60 with high precision and accuracy. Therefore, the detection accuracy of the magnetic field of the magnet 80 by the magnetic sensor 71 can be improved, and the axial position of the linear motion part 60 can be detected with high accuracy. In addition, since the magnetic sensor 71 can be attached to the substrate 70 having the inverter circuit 78 that supplies power to the motor part 40 via the terminal part 73, it is not necessary to provide a separate substrate near the linear motion part 60 to attach the magnetic sensor 71. In addition, it is not necessary to provide a complex structure to connect the magnetic sensor 71 and the substrate 70. As a result, it is possible to prevent the structure of the electric actuator 100 from becoming complicated. In addition, since it is not necessary to provide a separate substrate as described above, it is possible to prevent the number of parts of the electric actuator 100 from increasing. In addition, since the terminal part 73 can be extended from the substrate 70 to arrange the sensor main body part 72, the degree of freedom in arranging the sensor main body part 72 can be improved.

[0048] In this embodiment, the worker brings the board 70 with the magnetic sensor 71 attached thereto closer to the first case member 11 from above, and inserts the sensor main body 72, which is disposed at a distance below the board 70, into the holding recess 30 through the upper opening of the holding recess 30. The worker brings the board 70 closer to the first case member 11 until the board 70 comes into contact with each board support portion 16, and fixes the board 70 to each board support portion 16 with a plurality of screw members 77. As a result, the board 70 is fixed to the case 10, and the sensor main body 72 is held in the holding recess 30, and the magnetic sensor 71 is also fixed to the case 10.

[0049] When the motor section 40 and the linear motion section 60 are arranged side by side in the width direction (Y-axis direction) as in this embodiment, it is possible to arrange the board 70 having the inverter circuit 78 on the radial outside of the motor section 40 in order to prevent the electric actuator 100 from becoming large in the axial direction, for example. In particular, when the direction in which the linear motion section 60 extends from the transmission mechanism section 50 is opposite to the direction in which the output section 43a of the motor section 40 protrudes as in this embodiment, it is difficult to arrange the board 70 on either side of the motor section 40 and the linear motion section 60 in the axial direction. Therefore, the board 70 is likely to be arranged on the radial outside of the motor section 40. Here, the outer diameter of the motor section 40 is likely to be larger than the outer diameter of the linear motion section 60. Therefore, if the board 70 is arranged on the radial outside of the motor section 40, the distance from the board 70 to the linear motion section 60 becomes long, making it difficult to arrange the magnetic sensor 71 on the linear motion section 60 on which the magnet 80 is provided.

[0050] In contrast, according to this embodiment, the substrate 70 overlaps with the motor section 40 and the linear motion section 60 when viewed in a vertical direction intersecting both the axial direction and the width direction of the motor section 40. The sensor main body 72 is disposed vertically away from the substrate 70. Therefore, even if the substrate 70 is disposed radially outside the motor section 40 and the linear motion section 60 is disposed vertically away from the substrate 70, the sensor main body 72 disposed vertically away from the substrate 70 via the terminal section 73 can be disposed near the linear motion section 60. Conventionally, when the sensor main body 72 is disposed in this manner, the positioning accuracy of the sensor main body 72 is deteriorated, so that it was necessary to prepare a separate substrate for mounting the magnetic sensor 71 and to position the separate substrate near the linear motion section 60. In contrast, in this embodiment, the case 10 is provided with a holding recess 30 into which the sensor main body 72 can be inserted and held by disposing the substrate 70, so that the sensor main body 72 can be accurately positioned at a position away from the substrate 70. Furthermore, by arranging the substrate 70 at a position overlapping the motor section 40 and the linear motion section 60 when viewed in the vertical direction, the sensor main body 72 can be easily inserted into the holding recess 30. This allows the sensor main body 72 to be accurately arranged close to the linear motion section 60 without providing a separate substrate as described above. Therefore, the electric actuator 100 can be made smaller in size in the axial direction while further preventing the structure of the electric actuator 100 from becoming complicated.

[0051] Furthermore, according to this embodiment, the holding recess 30 is provided in the side wall 23a of the case 10 that faces the linear motion part 60 in the width direction (Y-axis direction). Therefore, by having the sensor main body 72 held in the holding recess 30, the sensor main body 72 can be accurately positioned near the linear motion part 60.

[0052] According to the present embodiment, the vertical distance L2 between the linear motion part 60 and the substrate 70 is greater than the vertical distance L1 between the motor part 40 and the substrate 70. Therefore, in the conventional configuration, it was difficult to precisely position the magnetic sensor 71 attached to the substrate 70 near the linear motion part 60. In contrast, in the present embodiment, as described above, the sensor body 72 is separated from the substrate 70 and the holding recess 30 is provided, so that the structure of the electric actuator 100 is prevented from becoming complicated, and the magnetic sensor 71 can be precisely positioned relative to the linear motion part 60. Furthermore, by making the distance L2 greater than the distance L1, the central axis J1 of the motor part 40 and the output axis J2 of the linear motion part 60 can be easily positioned at the same position in the vertical direction. This makes it easier to connect the motor part 40 and the linear motion part 60 via the transmission mechanism part 50.

[0053] In addition, when the transmission mechanism 50 is a mechanism for reducing the rotation of the motor 40 as in the present embodiment, the outer diameter of the second gear 52 is likely to be larger than the outer diameter of the first gear 51. In this case, if the substrate 70 is to be arranged at a position where it overlaps with the second gear 52 in the vertical direction, it is necessary to arrange the substrate 70 far away from the motor 40 in the vertical direction in order to prevent the substrate 70 from contacting the second gear 52, and the electric actuator 100 is likely to be large in the vertical direction. In addition, since the distance between the substrate 70 and the linear motion part 60 becomes larger, it is necessary to elongate the terminal part 73 in the vertical direction, and there is a possibility that it may be difficult to insert the sensor main body 72 into the holding recess 30 when arranging the substrate 70. In contrast, according to the present embodiment, the substrate 70 is arranged at a position different from the second gear 52 when viewed in the vertical direction. Therefore, it is easy to arrange the substrate 70 close to the motor 40, and the electric actuator 100 can be prevented from being large in the vertical direction. Furthermore, since the terminal portion 73 can be prevented from becoming long in the vertical direction, it is possible to prevent the sensor main body 72 from becoming difficult to insert into the holding recess 30.

[0054] Furthermore, according to this embodiment, the substrate 70 extends in the width direction (Y-axis direction) and is disposed across the opening 29a in the width direction. Therefore, the substrate 70 can be suitably disposed above the motor unit 40 and the linear motion unit 60. This makes it easier to insert the sensor main body 72 of the magnetic sensor 71 attached to the substrate 70 into the holding recess 30 when attaching the substrate 70 to the case 10.

[0055] According to the present embodiment, the case 10 is made of a non-magnetic material. The holding recess 30 is a hole that opens toward the substrate 70. Therefore, by inserting the sensor body 72 into the holding recess 30, the sensor body 72 can be appropriately held in the holding recess 30. Also, the sensor body 72 can be prevented from slipping out of the holding recess 30. Moreover, since the case 10 provided with the holding recess 30 is made of a non-magnetic material, even if the holding recess 30 is a hole, the magnetic field of the magnet 80 is not blocked by the wall of the case 10. Therefore, the magnetic field of the magnet 80 can be appropriately detected by the sensor body 72.

[0056] In this specification, the term "workers, etc." includes workers who perform each task and assembly equipment, etc. Each task may be performed by a worker alone, by an assembly equipment alone, or by both a worker and an assembly equipment.

[0057] The present invention is not limited to the above-described embodiment, and other configurations and methods may be adopted within the scope of the technical concept of the present invention. The holding recess may have any configuration as long as it is a recess that opens toward the substrate and can hold the sensor main body. The holding recess may have a configuration like the holding recess 230 in the case 210 of the electric actuator 200 shown in FIG. 8. As shown in FIG. 8, the holding recess 230 opens upward like the holding recess 30, and also opens on one side (+Y side) in the width direction of the side wall 23a. This allows the holding recess 230 to open toward the linear motion part 60. Therefore, the sensor main body 72 held in the holding recess 230 can be arranged closer to the linear motion part 60. Therefore, the detection accuracy of the magnetic field of the magnet 80 by the sensor main body 72 can be further improved. In addition, by opening the holding recess 230 toward the linear motion part 60, even if the case 210 is made of a magnetic material, the magnetic flux from the magnet 80 can easily flow to the sensor main body 72 held in the holding recess 230. Therefore, even if the case 210 is made of a magnetic material, the magnetic field of the magnet 80 can be easily detected by the sensor main body 72 in an appropriate manner.

[0058] The holding recess may hold the sensor main body in any manner. For example, the holding recess may be provided with an elastically deformable claw portion, and the sensor main body may be fixed to the holding recess by a snap-fit ​​structure using the claw portion. When a case having a holding recess is made by resin molding, the holding recess may be provided with a draft gradient in which the internal dimensions of the holding recess become larger toward the substrate. In this case, the internal dimensions of the holding recess become smaller as the sensor main body is inserted into the holding recess, making it easier to hold the sensor main body in a suitable manner within the holding recess. The location of the case where the holding recess is provided is not particularly limited as long as the sensor main body held in the holding recess can detect the magnetic field of the magnet. The material constituting the case is not particularly limited. The case may be made of metal.

[0059] The relative positional relationship between the linear motion part and the motor part is not particularly limited. The linear motion part and the motor part may be arranged side by side in the axial direction. The transmission mechanism part may have any structure as long as it is connected to the motor part and can linearly move the linear motion part.

[0060] The use of the electric actuator to which the present invention is applied is not particularly limited. The electric actuator may be mounted on any type of equipment. For example, the electric actuator may be mounted on a vehicle or on equipment other than a vehicle.

[0061] The present technology can be configured as follows. (1) An electric actuator comprising: a motor section, a transmission mechanism section connected to the motor section, a linear motion section connected to the transmission mechanism section and linearly moved by the transmission mechanism section, a case accommodating the motor section, the transmission mechanism section, and the linear motion section, a substrate having an inverter circuit that supplies power to the motor section, a magnet provided on the linear motion section, and a magnetic sensor capable of detecting a magnetic field of the magnet, the magnetic sensor having a sensor main body section disposed away from the substrate and a terminal section extending from the sensor main body section and fixed to the substrate, the case having a holding recess that holds the sensor main body section, the holding recess being open toward the substrate. (2) The electric actuator described in (1), wherein the linear motion part moves linearly in an axial direction of the motor part, the motor part and the linear motion part are arranged side by side in a first direction intersecting the axial direction of the motor part, the substrate overlaps with the motor part and the linear motion part when viewed in a second direction intersecting both the axial direction of the motor part and the first direction, and the sensor main body part is arranged away from the substrate in the second direction. (3) The electric actuator according to (2), wherein the retaining recess is provided in a wall portion of the case facing the linear motion portion in the first direction. (4) The electric actuator according to (3), wherein the distance in the second direction between the linear motion portion and the substrate is greater than the distance in the second direction between the motor portion and the substrate. (5) An electric actuator described in any one of (2) to (4), wherein the motor unit has an output portion protruding in the axial direction, the output portion is connected to the transmission mechanism unit, and the linear motion portion extends from the transmission mechanism unit in a direction opposite to the direction in which the output portion protrudes in the axial direction of the motor unit. (6) An electric actuator described in any one of (2) to (5), wherein the transmission mechanism has a first gear fixed to the motor and a second gear meshing with the first gear, and the base plate is positioned at a different position from the second gear when viewed in the second direction. (7) An electric actuator described in any one of (2) to (6), wherein the case has a housing portion that houses the motor portion and the linear motion portion therein, the housing portion has an opening that opens to one side in the second direction, and the substrate extends in the first direction and is positioned across the opening in the first direction. (8) The electric actuator according to any one of (1) to (7), wherein the retaining recess is open toward the linear motion portion. (9) The electric actuator according to any one of (1) to (7), wherein the case is made of a non-magnetic material, and the holding recess is a hole that opens toward the substrate.

[0062] The configurations and methods described in this specification can be combined as appropriate within the scope of not being mutually inconsistent. [Explanation of symbols]

[0063] 10,210...case, 23a...side wall portion (wall portion), 29...accommodation portion, 29a...opening portion, 30,230...retaining recess, 40...motor portion, 43a...output portion, 50...transmission mechanism portion, 51...first gear, 52...second gear, 60...linear motion portion, 70...substrate, 71...magnetic sensor, 72...sensor body portion, 73...terminal portion, 78...inverter circuit, 80...magnet, 100,200...electric actuator

Claims

1. A motor unit; a transmission mechanism connected to the motor; a linear motion part connected to the transmission mechanism and linearly moved by the transmission mechanism; a case that accommodates the motor unit, the transmission mechanism unit, and the linear motion unit therein; A substrate having an inverter circuit for supplying power to the motor unit; A magnet provided in the linear motion portion; a magnetic sensor capable of detecting a magnetic field of the magnet; Equipped with The magnetic sensor includes: a sensor body disposed away from the substrate; a terminal portion extending from the sensor body and fixed to the substrate; having the case has a holding recess for holding the sensor main body, The holding recess is open toward the substrate.

2. The linear motion portion linearly moves in an axial direction of the motor portion, the motor section and the linear motion section are arranged side by side in a first direction intersecting an axial direction of the motor section, the substrate overlaps the motor section and the linear motion section when viewed in a second direction intersecting both the axial direction of the motor section and the first direction, The electric actuator according to claim 1 , wherein the sensor body is disposed away from the substrate in the second direction.

3. The electric actuator according to claim 2 , wherein the retaining recess is provided in a wall portion of the case that faces the linear motion portion in the first direction.

4. The electric actuator according to claim 3 , wherein a distance in the second direction between the linear motion portion and the substrate is greater than a distance in the second direction between the motor portion and the substrate.

5. The motor portion has an output portion protruding in an axial direction, The output portion is connected to the transmission mechanism portion, The electric actuator according to claim 2 , wherein the linear motion portion extends from the transmission mechanism portion in a direction opposite to a direction in which the output portion projects in an axial direction of the motor portion.

6. The transmission mechanism includes: a first gear fixed to the motor unit; a second gear meshing with the first gear; having The electric actuator according to claim 2 , wherein the base plate is disposed at a position different from that of the second gear when viewed in the second direction.

7. the case has a housing portion that houses the motor portion and the linear motion portion therein, The storage portion has an opening portion that opens to one side in the second direction, The electric actuator according to claim 2 , wherein the substrate extends in the first direction and is disposed so as to straddle the opening in the first direction.

8. The electric actuator according to claim 1 , wherein the retaining recess is open toward the linear motion portion.

9. the case is made of a non-magnetic material, The electric actuator according to claim 1 , wherein the holding recess is a hole that opens toward the substrate.

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