Electric actuator

Abstract

To provide an electric actuator capable of suppressing increase in manufacturing cost.SOLUTION: In an electric actuator 10, a housing 11 for storing a motor unit therein has a first housing 12 having an opening unit 12a opening to one side in a first direction and a second housing 18 closing the opening unit and fixed to the first housing. The first housing has an annular groove unit 15 and a plurality of positioning units 16 protruding from an inner surface of the groove unit in a direction intersecting the first direction. The second housing has an annular projecting unit 19 projecting to the other side and arranged inside the groove unit. The positioning unit includes a plurality of first positioning units 16a opposing a first surface 19p of the projecting unit that faces an opening unit side of the outer surface, and a plurality of second positioning units 16d opposing a second surface 19r facing an opposite side to the first surface. The projecting unit is fixed to an inner surface of the groove unit by adhesive 90.SELECTED DRAWING: Figure 9

Description

[Technical Field]

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

[0002] An electronic control device is known that has a housing constructed by joining a case having a seal groove on the joining surface and a cover having a fixing protrusion that engages with the seal groove via an adhesive filled in the seal groove (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-004759 Summary of the Invention [Problem to be solved by the invention]

[0004] In order to increase the adhesive strength between the inner surface of the seal groove and the fixing ridge in the above electronic control device, the fixing ridge needs to be bonded while being positioned along the center of the seal groove. Therefore, in the above electronic control device, a positioning jig may be required to determine the position of the cover relative to the case in order to center the fixing ridge in the seal groove when the adhesive is cured. This increases the equipment costs required to manufacture the electronic control device, which may increase the manufacturing costs of the potential control device.

[0005] In view of the above circumstances, one aspect of the present invention has an object to provide an electric actuator that can suppress an increase in manufacturing costs. [Means for solving the problem]

[0006] One aspect of the electric actuator of the present invention includes a motor unit having a rotor rotatable about a motor axis and a housing that accommodates the motor unit. The housing includes a first housing having an opening that opens to one side in a first direction, and a second housing that closes the opening and is fixed to the first housing. The first housing has an annular groove that surrounds the opening and is recessed toward the other side in the first direction, and multiple positioning portions that protrude from the inner surface of the groove in a direction intersecting the first direction. The second housing has an annular protrusion that protrudes to the other side in the first direction and is disposed within the groove. The multiple positioning portions include multiple first positioning portions that face a first surface of the outer surface of the protrusion that faces the opening, and multiple second positioning portions that face a second surface of the outer surface of the protrusion that faces the opposite side from the first surface. The protrusions are fixed to the inner surface of the groove with an adhesive. [Effects of the Invention]

[0007] According to one aspect of the present invention, an increase in manufacturing costs of an electric actuator can be suppressed. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a first perspective view showing an electric actuator according to an embodiment. [Figure 2] FIG. 2 is a first cross-sectional view showing an electric actuator according to an embodiment. [Figure 3] FIG. 3 is a second cross-sectional view showing the electric actuator of the embodiment. [Figure 4] FIG. 4 is a perspective view showing a part of the electric actuator of one embodiment. [Figure 5] FIG. 5 is a plan view of a part of the electric actuator of one embodiment as viewed from one side in the first direction. [Figure 6] FIG. 6 is a second perspective view showing the electric actuator of the embodiment. [Figure 7]FIG. 7 is a third cross-sectional view showing the electric actuator of the embodiment. [Figure 8] FIG. 8 is a plan view of the second housing of the embodiment as viewed from the other side in the first direction. [Figure 9] FIG. 9 is a cross-sectional view showing a part of the electric actuator of one embodiment. [Figure 10] FIG. 10 is a first perspective view showing a transmission mechanism according to an embodiment. [Figure 11] FIG. 11 is a second perspective view showing the transmission mechanism of the embodiment. [Figure 12] FIG. 12 is a cross-sectional view showing an insertion process of the electric actuator of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] An electric actuator according to an embodiment of the present invention will be described below 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 components may differ from the actual structure in order to make each component easier to understand.

[0010] In each figure, the first direction D1 indicated by the arrow D1 is the direction in which the protrusion of the second housing protrudes. In this embodiment, the first direction D1 is the up-down direction of the electric actuator. In the following description, the side toward which the arrow of the first direction D1 points (+D1 side) will be referred to as "one side of the first direction D1" or "upper side," and the side opposite to the side toward which the arrow of the first direction D1 points (-D1 side) will be referred to as "the other side of the first direction D1" or "lower side."

[0011] In each figure, the second direction D2 indicated by the arrow D2 is the direction in which the motor axis extends. The second direction D2 is a direction that intersects with the first direction D1. In this embodiment, the second direction D2 is a direction perpendicular to the first direction D1. The second direction D2 does not have to be a direction perpendicular to the first direction D1. In this embodiment, the second direction D2 is the left-right direction of the electric actuator. In the following description, the side toward which the arrow of the second direction D2 points (+D2 side) is referred to as the "right side," and the side opposite to the side toward which the arrow of the second direction D2 points (-D2 side) is referred to as the "left side."

[0012] In each drawing, the third direction D3 indicated by the arrow D3 is a direction that intersects both the first direction D1 and the second direction D2. In this embodiment, the third direction D3 is a direction that is perpendicular to both the first direction D1 and the second direction D2. The third direction D3 does not have to be a direction that is perpendicular to the first direction D1. In this embodiment, the third direction D3 is the front-to-rear direction of the electric actuator. In the following description, the side toward which the arrow of the third direction D3 points (+D3 side) is referred to as the "front side," and the side opposite to the side toward which the arrow of the third direction D3 points (-D3 side) is referred to as the "rear side." Note that the terms upper side, lower side, right side, left side, front side, and rear side are simply names used to describe the relative positional relationships of the respective parts, and the actual positional relationships may be other than those indicated by these names.

[0013] As described above, the direction in which the motor axis J1, as shown appropriately in each drawing, extends is parallel to the second direction D2. The motor axis J1 is a virtual axis. In the following description, the radial direction centered on the motor axis J1 will be simply referred to as the "radial direction." The circumferential direction centered on the motor axis J1 will be simply referred to as the "circumferential direction." The circumferential direction is indicated by the arrow θ1 as appropriate in each drawing.

[0014] The electric actuator 10 of this embodiment shown in FIG. 1 is an electric actuator mounted on a vehicle. More specifically, it is mounted on a park-by-wire actuator device that is driven based on the shift operation of the vehicle driver. As shown in FIG. 2, the electric actuator 10 includes a housing 11, a motor unit 20, a transmission mechanism 30, and a cover member 60. As shown in FIG. 3, the electric actuator 10 includes an output shaft 39 and a substrate 70.

[0015] The housing 11 accommodates various components of the electric actuator 10, such as the motor unit 20, the transmission mechanism 30, the output shaft 39, and the circuit board 70. As shown in Fig. 1, the housing 11 has a substantially L-shaped box shape when viewed from a first direction D1. The housing 11 has a first housing 12 and a second housing 18.

[0016] As shown in Fig. 4, the first housing 12 is a generally L-shaped box when viewed from the first direction D1. The first housing 12 has an opening 12a that opens to the upper side (+D1 side), i.e., one side in the first direction D1. The first housing 12 has a side wall portion 13, an attachment portion 14, a groove portion 15, and a bottom wall portion 17. As shown in Fig. 5, the first housing 12 has a positioning portion 16.

[0017] 2 and 3, the side wall 13 surrounds each part of the electric actuator 10, such as the motor 20, the transmission mechanism 30, the output shaft 39, and the circuit board 70, from the outside in the second direction D2 and the outside in the third direction D3. As shown in FIG. 4, the side wall 13 is cylindrical and extends in the first direction D1. When viewed from the first direction D1, the side wall 13 is substantially L-shaped. The side wall 13 has a first side wall 13a, a second side wall 13c, a third side wall 13e, a fourth side wall 13g, a fifth side wall 13k, and a sixth side wall 13m.

[0018] The first side wall 13a is the front (+D3 side) portion of the side wall 13. The first side wall 13a is plate-shaped and extends in the second direction D2. The plate surface of the first side wall 13a faces the third direction D3. When viewed from the third direction D3, the first side wall 13a has a substantially rectangular shape with long sides extending in the second direction D2.

[0019] The second side wall portion 13c is the left side (-D2 side) portion of the side wall portion 13. The second side wall portion 13c is plate-shaped and extends from the left end of the first side wall portion 13a toward the rear (-D3 side). The plate surface of the second side wall portion 13c faces the second direction D2. When viewed from the second direction D2, the second side wall portion 13c has a substantially rectangular shape with long sides extending in the third direction D3.

[0020] The third side wall portion 13e is a plate-like portion extending from the rear end (-D3 side) of the second side wall portion 13c to the right side (+D2 side). The plate surface of the third side wall portion 13e faces the third direction D3. When viewed from the third direction D3, the third side wall portion 13e has a substantially rectangular shape with its long sides extending in the second direction D2. The dimension of the third side wall portion 13e in the second direction D2 is smaller than the dimension of the first side wall portion 13a in the second direction D2.

[0021] The fourth side wall portion 13g is a plate-like portion extending from the right end (+D2 side) of the third side wall portion 13e toward the front side (+D3 side). The plate surface of the fourth side wall portion 13g faces the second direction D2. When viewed from the second direction D2, the fourth side wall portion 13g has a substantially rectangular shape with its long sides extending in the third direction D3. The dimension of the fourth side wall portion 13g in the third direction D3 is smaller than the dimension of the second side wall portion 13c in the third direction D3. A connector mounting portion 13h is provided on the fourth side wall portion 13g.

[0022] The connector mounting portion 13h has a generally rectangular cylindrical shape and protrudes from the fourth side wall portion 13g to the right (+D2 side). As shown in FIG. 6, the connector mounting portion 13h opens to the right. The interior of the connector mounting portion 13h is connected to the interior of the housing 11 via a hole (not shown) that penetrates the fourth side wall portion 13g in the second direction D2. The connector mounting portion 13h holds a plurality of connector pins 13i.

[0023] 4, the fifth side wall portion 13k is a plate-like portion extending from the front end (+D3 side) of the fourth side wall portion 13g to the right side (+D2 side). The plate surface of the fifth side wall portion 13k faces the third direction D3. When viewed from the third direction D3, the fifth side wall portion 13k has a substantially rectangular shape with its long sides extending in the second direction D2. When viewed from the third direction D3, the right end of the fifth side wall portion 13k overlaps with the right end of the first side wall portion 13a.

[0024] The sixth side wall 13m is a plate-like member connecting the right end (+D2 side) of the first side wall 13a and the right end of the fifth side wall 13k. The plate surface of the sixth side wall 13m faces in a direction perpendicular to the first direction D1. The central portion of the sixth side wall 13m in the third direction D3 protrudes to the right in a rectangular shape.

[0025] The mounting portions 14 protrude outward from the side wall portions 13. The mounting portions 14 are provided with mounting holes 14a that penetrate the mounting portions 14 in the first direction D1. In this embodiment, the first housing 12 has three mounting portions 14. One mounting portion 14 protrudes forward (toward the +D3 side) from the first side wall portion 13a. The other mounting portion 14 protrudes leftward (toward the -D2 side) from the second side wall portion 13c. The other mounting portion 14 protrudes rearward (toward the -D3 side) from the third side wall portion 13e. Bolts (not shown) are passed through the mounting holes 14a of each mounting portion 14, and when the bolts are tightened into female threaded holes (not shown) provided in the vehicle, the electric actuator 10 is fixed to the vehicle body.

[0026] The groove portion 15 is a groove recessed downward (toward the -D1 side) from the surface of the side wall portion 13 facing upward (toward the +D1 side), i.e., toward the other side in the first direction D1. The groove portion 15 is annular and surrounds the opening 12a. When viewed from the first direction D1, the groove portion 15 is substantially L-shaped. As shown in FIG. 5, the groove portion 15 has a first groove portion 15a, a second groove portion 15c, a third groove portion 15e, a fourth groove portion 15g, a fifth groove portion 15k, a sixth groove portion 15m, and a linear portion 15p.

[0027] The first groove 15a is a groove provided on the surface of the first side wall 13a facing upward (+D1 side). The first groove 15a extends linearly in the second direction D2. The second groove 15c is a groove provided on the surface of the second side wall 13c facing upward. The second groove 15c extends linearly in the third direction D3. The front end (+D3 side) of the second groove 15c is connected to the left end (-D2 side) of the first groove 15a. The third groove 15e is a groove provided on the surface of the third side wall 13e facing upward. The third groove 15e extends linearly in the second direction D2. The left end of the third groove 15e is connected to the rear end (-D3 side) of the second groove 15c.

[0028] The fourth groove 15g is a groove provided on the surface facing upward of the fourth side wall 13g. The fourth groove 15g extends linearly in the third direction D3. The rear end (-D3 side) of the fourth groove 15g is connected to the right end (+D2 side) of the third groove 15e. The fifth groove 15k is a groove provided on the surface facing upward of the fifth side wall 13k. The fifth groove 15k extends linearly in the second direction D2. The left end (-D2 side) of the fifth groove 15k is connected to the front end (+D3 side) of the fourth groove 15g. The sixth groove 15m is a groove provided on the surface facing upward of the sixth side wall 13m. The sixth groove 15m connects the first groove 15a and the fifth groove 15k. The center of the sixth groove portion 15m in the third direction D3 protrudes to the right in a rectangular shape.

[0029] The straight line portions 15p are portions of the groove portion 15 that extend linearly when viewed from the first direction D1. The groove portion 15 has a plurality of straight line portions 15p. In this embodiment, the groove portion 15 has five straight line portions 15p. The plurality of straight line portions 15p include a first groove portion 15a, a second groove portion 15c, a third groove portion 15e, a fourth groove portion 15g, and a fifth groove portion 15k.

[0030] In the following description, the extension direction of the groove portion 15 refers to the extension direction of each of the groove portions 15a, 15c, 15e, 15g, 15k, and 15m that constitute the groove portion 15. In detail, the extension direction of the groove portion 15 is the second direction D2 for the first groove portion 15a, the third groove portion 15e, and the fifth groove portion 15k, the third direction D3 for the second groove portion 15c and the fourth groove portion 15g, and the extension direction of the portions that constitute the sixth groove portion 15m. In the following description, the term "viewed from the direction in which the grooves 15 extend" refers to the view from the second direction D2 for the first grooves 15a, the third grooves 15e, and the fifth grooves 15k, the view from the third direction D3 for the second grooves 15c and the fourth grooves 15g, and the view from the direction in which the components of the sixth groove 15m extend for the sixth groove 15m. Furthermore, in the following description, the center of the groove 15 refers to the center of the groove 15 in the direction perpendicular to the first direction D1 when viewed from the direction in which the grooves 15 extend.

[0031] The positioning portions 16 are protrusions that protrude in the second direction D2 or the third direction D3 from a surface of the inner surface of the groove portion 15 that is perpendicular to the first direction D1. That is, the positioning portions 16 protrude from the inner surface of the groove portion 15 in a direction that intersects with the first direction D1. In this embodiment, the first housing 12 has multiple positioning portions 16. The positioning portions 16 are arranged at intervals along the extension direction of the groove portion 15. The multiple positioning portions 16 include multiple first positioning portions 16a and multiple second positioning portions 16d. Each of the first positioning portions 16a protrudes toward the opposite side from the opening 12a from a surface of the inner surface of the groove portion 15 that faces away from the opening 12a. Each of the second positioning portions 16d protrudes toward the opening 12a from a surface of the inner surface of the groove portion 15 that faces toward the opening 12a. The detailed configuration of the positioning portions 16 will be described later.

[0032] 2, the bottom wall portion 17 is disposed below (on the -D1 side of) the motor portion 20 and the transmission mechanism 30. Although not shown, the bottom wall portion 17 is generally L-shaped when viewed from the first direction D1. The outer edge of the bottom wall portion 17 is connected to the lower end of the side wall portion 13 in the first direction D1. The bottom wall portion 17 has a motor accommodating portion 17a and a transmission mechanism accommodating portion 17c.

[0033] As shown in FIG. 6, the motor accommodating portion 17a has a semi-cylindrical shape that extends in the second direction D2 around the motor axis J1. The motor accommodating portion 17a protrudes downward (toward the -D1 side). As shown in FIG. 2, the motor accommodating portion 17a is a portion on the right side (toward the +D2 side) of the bottom wall portion 17. The lower portion of the motor unit 20 is accommodated inside the motor accommodating portion 17a.

[0034] As shown in FIG. 3, the transmission mechanism accommodating portion 17c is cylindrical and protrudes downward (toward -D1). As shown in FIG. 2, the transmission mechanism accommodating portion 17c is the left side (toward -D2) of the bottom wall portion 17. A lower portion of the transmission mechanism 30 is accommodated inside the transmission mechanism accommodating portion 17c. As shown in FIG. 7, the transmission mechanism accommodating portion 17c is provided with a first support portion 17d and a second support portion 17e. As shown in FIG. 5, the transmission mechanism accommodating portion 17c is provided with a pin holding portion 17f. As shown in FIG. 3, the transmission mechanism accommodating portion 17c is provided with a bottom wall hole portion 17h and a cylindrical portion 17i.

[0035] As shown in FIG. 2, the first support portion 17d protrudes downward (toward the -D1 side). The first support portion 17d is substantially cylindrical and has a first axis J2 as its center. The first support portion 17d opens upward (toward the +D1 side). The first support portion 17d is provided on the front side (toward the +D3 side) of the transmission mechanism housing portion 17c. The first axis J2 shown in each drawing is a virtual axis extending in the first direction D1. The first axis J2 intersects with the motor axis J1. In this embodiment, the first axis J2 is perpendicular to the motor axis J1. In the following description, the radial direction centered on the first axis J2 will be simply referred to as the "first radial direction."

[0036] As shown in FIG. 7, the second support portion 17e protrudes downward (toward the -D1 side). The second support portion 17e is substantially cylindrical and has a center on the second axis J3. The second support portion 17e opens upward (toward the +D1 side). The second support portion 17e is provided rearward (toward the -D3 side) and to the left (toward the -D2 side) of the first support portion 17d. The second axis J3 shown in each drawing as appropriate is a virtual axis extending in the first direction D1. In the following description, the radial direction centered on the second axis J3 will be simply referred to as the "second radial direction."

[0037] The pin holding portion 17f shown in FIG. 5 has a substantially rectangular parallelepiped shape and protrudes upward (toward +D1) from the bottom wall portion 17. The pin holding portion 17f is disposed to the left (toward -D2) of the fourth side wall portion 13g. The pin holding portion 17f is connected to the fourth side wall portion 13g. A plurality of connector pins 13i are passed through the inside of the pin holding portion 17f. The pin holding portion 17f holds each connector pin 13i. Each connector pin 13i protrudes upward from the pin holding portion 17f. As shown in FIG. 4, each connector pin 13i is connected to the substrate 70.

[0038] As shown in FIG. 3, the bottom wall hole 17h is a hole that penetrates the transmission mechanism accommodating portion 17c in the first direction D1. When viewed from the first direction D1, the bottom wall hole 17h has a substantially circular shape centered on the output axis J4. A third bearing 97 is fixed to the inner circumferential surface of the bottom wall hole 17h. The third bearing 97 has a substantially annular shape centered on the output axis J4. In this embodiment, the third bearing 97 is a ball bearing. The third bearing 97 may be a rolling bearing other than a ball bearing, or may be a plain bearing. The output axis J4 shown in each drawing as appropriate is a virtual axis extending in the first direction D1. In the following description, the radial direction centered on the output axis J4 will be simply referred to as the "output radial direction."

[0039] The cylindrical portion 17i protrudes downward (toward the -D1 side) from the edge of the bottom wall hole 17h. The cylindrical portion 17i has a substantially cylindrical shape centered on the output axis J4. The lower portion of the output shaft 39 is disposed inside the cylindrical portion 17i.

[0040] 2, the second housing 18 is fixed to the upper end of the first housing 12. The second housing 18 closes the opening 12a of the first housing 12 from the upper side (+D1 side). The second housing 18 has a lid portion 18a, a protruding support portion 18c, and a protruding portion 19.

[0041] As shown in FIG. 1, the lid portion 18a is plate-shaped and extends in a direction perpendicular to the first direction D1. The plate surface of the lid portion 18a faces the first direction D1. When viewed from the first direction D1, the lid portion 18a is substantially L-shaped. When viewed from the first direction D1, the outer edge of the lid portion 18a overlaps with the side wall portion 13. As shown in FIG. 2, the lid portion 18a closes the opening 12a from above (the +D1 side). The lid portion 18a contacts the surface of the side wall portion 13 facing upward in the first direction D1. The lid portion 18a closes the groove portion 15 from above.

[0042] The protruding support portion 18c is a columnar member that protrudes downward (toward the -D1 side) from the right end (toward the +D2 side) of the cover portion 18a. The protruding support portion 18c faces the sixth side wall portion 13m with a gap in between in the second direction D2.

[0043] The protrusion 19 protrudes downward (-D1 side) from the lid portion 18a, i.e., toward the other side in the first direction D1. As shown in FIG. 8, the protrusion 19 is annular and extends in a direction perpendicular to the first direction D1 along the edge of the lid portion 18a. Although not shown, the entire protrusion 19 is disposed inside the groove portion 15. The protrusion 19 has a first protrusion 19a, a second protrusion 19c, a third protrusion 19e, a fourth protrusion 19g, a fifth protrusion 19k, and a sixth protrusion 19m. As shown in FIG. 9, the protrusion 19 has a first surface 19p, a second surface 19r, and a tip portion 19s.

[0044] As shown in Fig. 8, the first protrusion 19a is the front side (+D3 side) of the protrusion 19. The first protrusion 19a is plate-shaped and extends in the second direction D2. The plate surface of the first protrusion 19a faces the third direction D3. As shown in Fig. 9, the first protrusion 19a is disposed inside the first groove 15a.

[0045] As shown in FIG. 8, the second protrusion 19c is the left side (-D2 side) of the protrusion 19. The second protrusion 19c is a plate-like member extending from the left end of the first protrusion 19a toward the rear side (-D3 side). The plate surface of the second protrusion 19c faces the second direction D2. Although not shown, the second protrusion 19c is disposed inside the second groove 15c.

[0046] The third protrusion 19e is a plate-like member extending from the rear end (-D3 side) of the second protrusion 19c to the right side (+D2 side). The plate surface of the third protrusion 19e faces the third direction D3. The dimension of the third protrusion 19e in the second direction D2 is smaller than the dimension of the first protrusion 19a in the second direction D2. As shown in FIG. 3, the third protrusion 19e is disposed inside the third groove 15e.

[0047] As shown in Fig. 8, the fourth protrusion 19g is a plate-like member extending from the right end (+D2 side) of the third protrusion 19e toward the front (+D3 side). The plate surface of the fourth protrusion 19g faces the second direction D2. The dimension of the fourth protrusion 19g in the third direction D3 is smaller than the dimension of the second protrusion 19c in the third direction D3. Although not shown, the fourth protrusion 19g is disposed inside the fourth groove 15g.

[0048] The fifth protrusion 19k is a plate-like member extending from the front end (+D3 side) of the fourth protrusion 19g to the right (+D2 side). The plate surface of the fifth protrusion 19k faces the third direction D3. Although not shown, the fifth protrusion 19k is disposed inside the fifth groove 15k.

[0049] The sixth protrusion 19m is a plate-like member that connects the right end (+D2 side) of the first protrusion 19a and the right end of the fifth protrusion 19k. The plate surface of the sixth protrusion 19m faces a direction perpendicular to the first direction D1. The central portion of the sixth protrusion 19m in the third direction D3 protrudes to the right in a rectangular shape. As shown in FIG. 2, the sixth protrusion 19m is disposed inside the sixth groove 15m.

[0050] As shown in FIG. 9, the first surface 19p is the surface of the outer surface of the protrusion 19 that faces the opening 12a. The first surface 19p faces a direction perpendicular to the first direction D1. As described above, the protrusion 19 is disposed inside the groove 15. Also, as described above, the groove 15 surrounds the opening 12a. Therefore, as shown in FIG. 8, the first surfaces 19p of the portions 19a, 19c, 19e, 19g, 19k, and 19m of the protrusion 19 face the inside of the second housing 18 when viewed from the first direction D1.

[0051] As shown in Fig. 9, the second surface 19r is the surface of the outer surface of the protrusion 19 that faces away from the opening 12a. The second surface 19r faces away from the first surface 19p. The second surface 19r faces a direction perpendicular to the first direction D1. As shown in Fig. 8, the second surfaces 19r of the portions 19a, 19c, 19e, 19g, 19k, and 19m of the protrusion 19 face outward from the second housing 18 when viewed from the first direction D1.

[0052] As shown in FIG. 9, the tip 19s is the lower side (-D1 side) of the protrusion 19, i.e., the portion on the other side in the first direction D1. The tip 19s is located lower than the positioning portion 16. The lower end of the tip 19s is the lower end of the protrusion 19. The dimension of the tip 19s in a direction perpendicular to the extension direction of the protrusion 19 decreases as the tip 19s extends downward. More specifically, the outer surface portion of the first surface 19p of the tip 19s is located away from the opening 12a as it extends downward. The outer surface portion of the second surface 19r of the tip 19s is located towards the opening 12a as it extends downward.

[0053] The portion of the protrusion 19 below the positioning portion 16 (on the -D1 side) is fixed to the inner surface of the groove 15 with an adhesive 90. As a result, the protrusion 19 is fixed to the inner surface of the groove 15 with the adhesive 90. Therefore, the second housing 18 is fixed to the first housing 12. As the adhesive 90, for example, a thermosetting adhesive such as an epoxy resin adhesive, a melamine resin adhesive, a phenol resin adhesive, or an adhesive obtained by mixing these adhesives can be used. In this embodiment, the adhesive 90 is an epoxy resin adhesive.

[0054] As shown in FIG. 2, the cover member 60 is disposed above (on the +D1 side of) the transmission mechanism 30. The cover member 60 covers the transmission mechanism 30 from above. The cover member 60 has a cover main body 61 and a protrusion 65. As shown in FIG. 5, the cover main body 61 is plate-shaped and extends in a direction perpendicular to the first direction D1. The plate surface of the cover main body 61 faces the first direction D1. The cover main body 61 is fixed to the bottom wall 17 by four screws 91. This fixes the cover member 60 to the second housing 18. The cover main body 61 is provided with a first hole 61a, a board holding portion 62, and a terminal holding portion 63.

[0055] As shown in FIG. 3, the first hole 61a is a hole that penetrates the cover main body 61 in the first direction D1. When viewed from the first direction D1, the first hole 61a has a substantially circular shape centered on the output axis J4. As shown in FIG. 2, the board holding portion 62 is a columnar shape that protrudes upward (toward +D1) from the cover main body 61. As shown in FIG. 5, five board holding portions 62 are provided on the cover main body 61. Each board holding portion 62 holds a board 70.

[0056] As shown in FIG. 2, the terminal holding portion 63 protrudes upward (toward +D1) from the cover main body portion 61. As shown in FIG. 5, when viewed from the first direction D1, the terminal holding portion 63 has a generally rectangular shape with its long sides extending in the third direction D3. The terminal holding portion 63 is disposed to the left (toward -D2) of the motor portion 20. The terminal holding portion 63 is disposed alongside the motor portion 20 in the second direction D2. The terminal holding portion 63 holds two connection terminals 92. Each connection terminal 92 protrudes upward from the terminal holding portion 63.

[0057] As shown in Fig. 3, the protrusion 65 is cylindrical and protrudes upward (towards +D1) from the cover main body 61. The protrusion 65 opens downward (towards -D1). As shown in Fig. 5, when viewed from the first direction D1, the protrusion 65 has a substantially semicircular shape with an arc portion protruding to the right (towards +D2). The protrusion 65 is provided with a second hole 65a and a third hole 65c.

[0058] As shown in FIG. 7, the second hole portion 65a and the third hole portion 65c are holes that penetrate the protrusion 65 in the first direction D1. When viewed from the first direction D1, the second hole portion 65a has a substantially circular shape centered on the first axis J2. As shown in FIG. 5, the second hole portion 65a is provided on the left side (-D2 side) of the motor portion 20. When viewed from the first direction D1, the second hole portion 65a overlaps with the first support portion 17d. When viewed from the first direction D1, the third hole portion 65c has a substantially circular shape centered on the second axis J3. As shown in FIG. 5, the third hole portion 65c is provided rearward (-D3 side) and to the left of the second hole portion 65a. When viewed from the first direction D1, the third hole portion 65c overlaps with the second support portion 17e.

[0059] 2, motor unit 20 is accommodated in the right-hand side (+D2 side) of housing 11. As described above, the lower side (-D1 side) of motor unit 20 is accommodated in motor accommodating portion 17a. Motor unit 20 has rotor 22 and stator 23.

[0060] The rotor 22 is rotatable about the motor axis J1. The rotor 22 has a rotor core 22a, a plurality of motor magnets 22b, and a motor shaft 24. The rotor core 22a is substantially annular and centered on the motor axis J1. Each motor magnet 22b is fixed to the outer circumferential surface of the rotor core 22a. Each motor magnet 22b is arranged along the outer circumferential surface of the rotor core 22a.

[0061] The motor shaft 24 has a generally cylindrical shape extending in the second direction D2 around the motor axis J1. A rotor core 22a is fixed to the outer circumferential surface of the motor shaft 24. A left end (-D2 side) of the motor shaft 24 is located inside the transmission mechanism housing 17c. A right end (+D2 side) of the motor shaft 24 is rotatably supported around the motor axis J1 by a first bearing 94. A left portion of the motor shaft 24 is rotatably supported around the motor axis J1 by a second bearing 95. As a result, the motor shaft 24 is rotatable around the motor axis J1. In this embodiment, the first bearing 94 and the second bearing 95 are plain bearings. The first bearing 94 and the second bearing 95 may be ball bearings. The first bearing 94 is held by the protruding support portion 18c and the bottom wall portion 17. The second bearing 95 is held by the terminal holder 63 and the bottom wall portion 17.

[0062] The stator 23 is disposed radially outside the rotor 22. The stator 23 is disposed facing the rotor 22 with a radial gap therebetween. The stator 23 includes a stator core 23a, an insulator 23e, and a plurality of coil portions 23f. The stator core 23a is substantially annular and centered on the motor axis J1. The stator core 23a surrounds the rotor 22 from the radial outside. A lower portion (-D1 side) of the outer peripheral surface of the stator core 23a is fixed to the inner surface of the motor accommodating portion 17a. This fixes the stator 23 to the housing 11.

[0063] The insulator 23e insulates the stator core 23a from each of the coil portions 23f. In this embodiment, the insulator 23e is made of resin. The insulator 23e is attached to the stator core 23a. Each of the coil portions 23f is attached to the stator core 23a via the insulator 23e. Each of the coil portions 23f is arranged along the circumferential direction. Although not shown in the drawings, each of the coil portions 23f is electrically connected to a connection terminal 92.

[0064] The transmission mechanism 30 is disposed to the left (-D2 side) of the motor unit 20. As described above, the lower side (-D1 side) of the transmission mechanism 30 is housed inside the transmission mechanism housing portion 17c. The upper side (+D1 side) of the transmission mechanism 30 is covered by a cover member 60. The transmission mechanism 30 is coupled to the motor shaft 24. As shown in FIG. 3, the transmission mechanism 30 is coupled to the output shaft 39. That is, the transmission mechanism 30 is coupled to the motor shaft 24 and the output shaft 39. The transmission mechanism 30 transmits the rotation of the motor shaft 24 to the output shaft 39. In this embodiment, the transmission mechanism 30 transmits the rotation of the motor shaft 24 to the output shaft 39 at a reduced speed. The transmission mechanism 30 may transmit the rotation of the motor shaft 24 to the output shaft 39 at an increased speed, or may transmit rotation to the output shaft 39 at the same rotational speed as the rotation of the motor shaft 24. 10, the transmission mechanism 30 has a first gear 31, a first-stage gear 32, a second-stage gear 35, and an output gear 38. The rotation of the motor shaft 24 is transmitted through the first gear 31, the first-stage gear 32, the second-stage gear 35, the output gear 38, and the output shaft 39 in this order.

[0065] The first gear 31 transmits the rotation of the motor shaft 24 to the second stage gear 35. The first gear 31 has a generally cylindrical shape extending in the second direction D2. The motor shaft 24 passes through the first gear 31. The inner peripheral surface of the first gear 31 is fixed to the outer peripheral surface of the motor shaft 24. This connects the transmission mechanism 30 to the motor shaft 24. The first gear 31 is rotatable around the motor axis J1 together with the motor shaft 24. In this embodiment, the first gear 31 is a bevel gear. The outer diameter of the first gear 31 decreases toward the left (-D2 side). A first gear portion 31a is provided on the outer peripheral surface of the first gear 31.

[0066] The first-stage gear 32 transmits the rotation of the first gear 31 to the second-stage gear 35. As shown in FIG. 2, the first-stage gear 32 is substantially cylindrical and centered on the first axis J2. A first shaft portion 32a passes through the first-stage gear 32 in the first direction D1. The upper end of the first shaft portion 32a is supported by the inner circumferential surface of the second hole portion 65a. The lower end of the first shaft portion 32a is supported by the inner circumferential surface of the first support portion 17d. The first-stage gear 32 is supported by the first shaft portion 32a so as to be rotatable about the first axis J2. The first-stage gear 32 has a first large-diameter gear 33 and a first small-diameter gear 34.

[0067] The first large-diameter gear 33 has a substantially annular plate shape centered on the first axis J2. The first large-diameter gear 33 is rotatable about the first axis J2. As shown in FIG. 10, the first large-diameter gear 33 is a bevel gear. The outer diameter of the first large-diameter gear 33 decreases toward the upper side (+D1 side). The first large-diameter gear 33 has a first large-diameter gear portion 33a on its upper surface that meshes with the first gear portion 31a. The number of teeth of the first large-diameter gear portion 33a is greater than the number of teeth of the first gear portion 31a. As a result, the rotation of the motor shaft 24 and the first gear 31 is transmitted to the first stage gear 32 at a reduced speed.

[0068] The first small diameter gear 34 has a substantially circular ring shape centered on the first axis J2. The first small diameter gear 34 is disposed above (on the +D1 side of) the first large diameter gear 33. The first small diameter gear 34 is connected to the first large diameter gear 33 in the first direction D1. The first small diameter gear 34 is rotatable around the first axis J2 together with the first large diameter gear 33. A first small diameter gear portion 34a is provided on a surface of the first small diameter gear 34 facing outward in the first radial direction.

[0069] The second-stage gear 35 transmits the rotation of the first-stage gear 32 to the output gear 38. The second-stage gear 35 has a substantially annular shape centered on the second axis J3. As shown in FIG. 7, a second shaft portion 35a passes axially through the second-stage gear 35. The upper end of the second shaft portion 35a is supported by the inner circumferential surface of the third hole portion 65c. The lower end of the second shaft portion 35a is supported by the inner circumferential surface of the second support portion 17e. The second-stage gear 35 is supported by the second shaft portion 35a so as to be rotatable about the second axis J3. The second-stage gear 35 has a second large-diameter gear 36 and a second small-diameter gear 37.

[0070] The second large-diameter gear 36 has a substantially circular ring shape centered on the second axis J3. The second large-diameter gear 36 is rotatable around the second axis J3. As shown in FIG. 10, a second large-diameter gear portion 36a that meshes with the first small-diameter gear portion 34a is provided on a surface of the second large-diameter gear 36 facing outward in the second radial direction. The number of teeth of the second large-diameter gear portion 36a is greater than the number of teeth of the first small-diameter gear portion 34a. As a result, the rotation of the first-stage gear 32 is transmitted to the second-stage gear 35 at a reduced speed.

[0071] The second small diameter gear 37 has a substantially circular ring shape centered on the second axis J3. The second small diameter gear 37 is disposed below (on the -D1 side of) the second large diameter gear 36. The second small diameter gear 37 is connected to the second large diameter gear 36 in the first direction D1. The second small diameter gear 37 is rotatable around the second axis J3 together with the second large diameter gear 36. A second small diameter gear portion 37a is provided on a surface of the second small diameter gear 37 facing outward in the second radial direction.

[0072] The output gear 38 shown in FIG. 11 transmits the rotation of the second-stage gear 35 to the output shaft 39. The output gear 38 is rotatable around the output axis J4. The output gear 38 has an output gear main body 38a and an output gear portion 38d. The output gear main body 38a is a generally fan-shaped plate centered on the output axis J4. The plate surface of the output gear main body 38a faces the first direction D1. As shown in FIG. 3, the output gear main body 38a is provided with a hole 38b. The hole 38b is a hole that penetrates the output gear main body 38a in the first direction D1. When viewed from the first direction D1, the hole 38b has a generally circular shape centered on the output axis J4. The output shaft 39 passes through the hole 38b in the first direction D1. The inner circumferential surface of the hole 38b is fixed to the outer circumferential surface of the output shaft 39. As a result, the transmission mechanism 30 is connected to the output shaft 39 .

[0073] As shown in Fig. 11, the output gear portion 38d is provided on a portion of the outer circumferential surface of the output gear main body portion 38a that forms an arc of the output gear main body portion 38a. The output gear portion 38d extends in an arc shape centered on the output axis J4. The output gear portion 38d meshes with the second small diameter gear portion 37a. This allows the rotation of the second stage gear 35 to be transmitted to the output gear 38. In this embodiment, the rotation of the second stage gear 35 is transmitted to the output gear 38 at a reduced speed.

[0074] As shown in FIG. 3, the output shaft 39 has a generally cylindrical shape extending in the first direction D1 around the output axis J4. The rotation of the motor shaft 24 is reduced in speed and transmitted to the output shaft 39 via the transmission mechanism 30. As described above, the output shaft 39 is fixed to the inner circumferential surface of the hole 38b. The upper end of the output shaft 39 is located inside the first hole 61a of the cover member 60. A portion of the outer circumferential surface of the output shaft 39 below the output gear 38 (on the -D1 side) is supported by the third bearing 97 so as to be rotatable about the output axis J4. The lower end of the output shaft 39 is located inside the cylindrical portion 17i. The output shaft 39 is provided with a connecting recess 39a and a shaft recess 39c.

[0075] The coupling recess 39a is recessed upward (toward +D1) from the surface of the output shaft 39 facing downward (toward -D1). A driven member (not shown) can be inserted into the coupling recess 39a from below. When a plurality of spline grooves on the outer circumferential surface of the driven member are fitted into a plurality of spline grooves on the inner circumferential surface of the coupling recess 39a, the coupling recess 39a and the driven member are coupled to each other. In this embodiment, the driven member is, for example, a manual shaft of a vehicle. The electric actuator 10 drives the manual shaft based on a shift operation by the driver to change gears of the vehicle.

[0076] The shaft recess 39c is a groove recessed inward in the output radial direction from the outer circumferential surface of the output shaft 39. The shaft recess 39c is provided on the lower side (-D1 side) of the output shaft 39. The shaft recess 39c extends around the entire circumference along the outer circumferential surface of the output shaft 39. An O-ring 93 is fitted into the output shaft 39. The O-ring 93 contacts the inner circumferential surface of the cylindrical portion 17i. The O-ring 93 seals the gap between the output shaft 39 and the housing 11.

[0077] The magnet 81 is fixed to the upper end of the output shaft 39 via a magnet holder 82. This allows the magnet 81 to rotate around the output axis J4 together with the output shaft 39. The magnet 81 faces the substrate 70 with a gap in the first direction D1.

[0078] The substrate 70 supplies current to the motor unit 20. The substrate 70 controls the direct current supplied to the coil unit 23f. As shown in FIG. 4, in this embodiment, the substrate 70 is a substantially L-shaped plate. The plate surface of the substrate 70 faces the first direction D1. As shown in FIGS. 2 and 3, the substrate 70 is disposed above (on the +D1 side of) the transmission mechanism 30. As shown in FIG. 4, each substrate holder 62 passes through the substrate 70 in the first direction D1. The substrate 70 is held by each substrate holder 62. As a result, the substrate 70 is held by the cover member 60.

[0079] Each connector pin 13i extends through the substrate 70 in the first direction D1. The substrate 70 is connected to each connector pin 13i. As a result, the substrate 70 is electrically connected to an external power supply (not shown) via each connector pin 13i. The substrate 70 generates a current to be supplied to the coil portion 23f using a current supplied from the external power supply. Furthermore, each connection terminal 92 extends through the substrate 70 in the first direction D1. The substrate 70 is connected to each connection terminal 92. As described above, each coil portion 23f is electrically connected to the connection terminal 92. As a result, the substrate 70 is electrically connected to each coil portion 23f via each connection terminal 92 and supplies a current to the coil portion 23f. In other words, the substrate 70 supplies a current to the motor portion 20. As a result, the substrate 70 drives the motor portion 20. As shown in FIG. 3, a magnetic sensor 72 is mounted on the surface of the substrate 70 facing downward (−D1 side).

[0080] The magnetic sensor 72 faces the magnet 81 in the first direction D1. The magnetic sensor 72 is a magnetic sensor that can detect the magnetic field of the magnet 81. The magnetic sensor 72 is, for example, a magnetic sensor that includes a Hall element such as a Hall IC. When the magnet 81 rotates around the output axis J4 together with the output shaft 39, the magnetic sensor 72 detects a change in the magnetic field of the magnet 81. As a result, the magnetic sensor 72 detects the rotation of the motor shaft 24.

[0081] As described above, the first positioning portions 16a shown in FIG. 9 protrude from the inner surface of the groove portion 15 facing away from the opening 12a toward the side opposite the opening 12a. Each first positioning portion 16a faces the first surface 19p of the protrusion 19. As described above, the second positioning portions 16d protrude from the inner surface of the groove portion 15 facing toward the opening 12a toward the opening 12a. Each second positioning portion 16d faces the second surface 19r of the protrusion 19. As a result, the protrusion 19 is positioned between the first positioning portion 16a and the second positioning portion 16d inside the groove portion 15. Therefore, in this embodiment, the protrusion 19 can be positioned along the center of the groove portion 15 with high precision.

[0082] In this embodiment, at least one first positioning portion 16a is in contact with the protrusion 19. That is, at least one positioning portion 16 is in contact with the protrusion 19. This allows the protrusion 19 to be positioned more accurately along the center of the groove 15 than when the positioning portions 16 are not in contact with the protrusion 19. Note that not all of the first positioning portions 16a may be in contact with the protrusion 19, and at least one second positioning portion 16d may be in contact with the protrusion 19. Even in this case, the protrusion 19 can be positioned more accurately along the center of the groove 15 than when the positioning portions 16 are not in contact with the protrusion 19. In this embodiment, at least one first positioning portion 16a and at least one second positioning portion 16d are in contact with the protrusion 19. This allows the protrusion 19 to be positioned more accurately along the center of the groove 15.

[0083] As shown in FIG. 5, one second positioning portion 16d is disposed between adjacent first positioning portions 16a along the extension direction of the groove portion 15. That is, the first positioning portions 16a and the second positioning portions 16d are alternately disposed along the extension direction of the groove portion 15. Furthermore, at least one first positioning portion 16a and at least one second positioning portion 16d are provided in each of the first groove portion 15a, the second groove portion 15c, the third groove portion 15e, the fourth groove portion 15g, and the fifth groove portion 15k. That is, a first positioning portion 16a and a second positioning portion 16d are provided in each of the multiple linear portions 15p. In this embodiment, a first positioning portion 16a and a second positioning portion 16d are also provided in the sixth groove portion 15m.

[0084] As shown in FIG. 9 , the surface 16b facing the upper side (+D1 side) of each first positioning portion 16a is positioned downward (toward -D1 side) toward the center of the groove portion 15. That is, the surface 16b facing the upper side of each first positioning portion 16a is an inclined surface that is positioned downward toward the protrusion 19. The surface 16e facing the upper side of each second positioning portion 16d is positioned downward toward the center of the groove portion 15. That is, the surface 16e facing the upper side of each second positioning portion 16d is an inclined surface that is positioned downward toward the protrusion 19. As a result, the upper side of each of the multiple positioning portions 16, i.e., the surface facing one side in the first direction D1, is an inclined surface that is positioned downward toward the protrusion 19, i.e., the other side in the first direction D1.

[0085] Next, in this embodiment, a fixing process Pf for fixing the second housing 18 to the first housing will be described. The fixing process Pf is part of the assembly process of the electric actuator 10. The fixing process Pf includes a filling process P1 for filling the entire circumference of the groove 15 with uncured adhesive 90, an insertion process P2 for inserting the protrusion 19 into the groove 15, and a curing process P3 for curing the adhesive 90 to fix the second housing 18 to the first housing. In the following description, the term "worker, etc." includes the worker and assembly device performing each process. The work of each process may be performed by the worker alone, by the assembly device alone, or by both the worker and the assembly device.

[0086] In the filling step P1, the uncured adhesive 90 is filled all around the groove 15. As shown in FIG. 12 , the worker fills the uncured adhesive 90 inside the groove 15 of the first housing 12, to which the components of the electric actuator 10, such as the motor unit 20, the transmission mechanism 30, the output shaft 39, and the circuit board 70, have been attached in advance. In this embodiment, the worker fills the uncured adhesive 90 in the portion of the groove 15 below the positioning portions 16 (on the -D1 side). The worker may also fill the uncured adhesive 90 in the portion of the groove 15 above the positioning portions 16 (on the +D1 side). Although not shown in the drawings, the worker fills the uncured adhesive 90 all around the groove 15. When the worker has filled the adhesive 90 all around the groove 15, the filling step P1 is completed.

[0087] In the insertion step P2, the protrusion 19 is inserted into the groove 15. The worker or the like moves the second housing 18, which is disposed on the upper side (+D1 side) of the first housing 12, downward (-D1 side) to insert the protrusion 19 into the groove 15. As described above, the upward-facing surface 16b of each first positioning portion 16a is an inclined surface that is positioned downward toward the center of the groove 15. The upward-facing surface 16e of each second positioning portion 16d is an inclined surface that is positioned downward toward the center of the groove 15. Therefore, in the insertion step P2, the upward-facing surfaces 16b and 16e of each positioning portion 16 can guide the protrusion 19 to the center of the groove 15. This allows the protrusion 19 to be easily inserted into the center of the groove 15. Therefore, the protrusion 19 can be positioned along the center of the groove 15 with high precision. As described above, the dimension of the tip 19s of the protrusion 19 in the direction perpendicular to the direction in which the protrusion 19 extends decreases as the tip 19s extends downward. Therefore, in the insertion step P2, the tip 19s is prevented from getting caught on the positioning portions 16, and the protrusion 19 can be easily inserted into the groove 15. As shown in FIG. 9 , the insertion step P2 is completed when the second housing 18 is moved downward until the lid portion 18a and the upward-facing surface of the side wall portion 13 come into contact with each other in the first direction D1. At this time, the tip portion of the protrusion 19 is located below the positioning portions 16. The tip portion of the protrusion 19 is located inside the uncured adhesive 90.

[0088] In the curing process P3, the uncured adhesive 90 is cured to fix the second housing 18 to the first housing 12. First, a worker or the like uses a pressing jig (not shown) to press the second housing 18 downward (toward the -D1 side) against the first housing 12. This maintains contact between the lid portion 18a and the surface of the side wall portion 13 facing the upper side (+D1 side) in the first direction D1. Next, the worker or the like heats the first housing 12, to which the second housing 18 is pressed by the pressing jig, in a heating furnace. When the uncured adhesive 90 cures, the protrusion 19 is fixed to the inner surface of the groove 15 by the adhesive 90. More specifically, the lower (-D1 side) portion of the first surface 19p of the protrusion and the lower portion of the second surface 19r of the protrusion are each fixed to the inner surface of the groove 15 by the adhesive 90. Furthermore, the second housing 18 is fixed to the first housing 12 with the lid portion 18a and the upward surface of the side wall portion 13 in contact in the first direction D1. The worker or the like cures the uncured adhesive 90 to fix the second housing 18 to the first housing 12, and the curing step P3 is completed. When the curing step P3 is completed, the fixing step Pf is completed.

[0089] According to this embodiment, the first housing 12 has an annular groove 15 that surrounds the opening 12a and is recessed downward (−D1 side), i.e., toward the other side in the first direction D1, and a plurality of positioning portions 16 that protrude from the inner surface of the groove 15 in a direction intersecting the first direction D1. The second housing 18 has an annular protrusion 19 that protrudes downward and is disposed inside the groove 15. The plurality of positioning portions 16 include a plurality of first positioning portions 16a that face a first surface 19p on the outer surface of the protrusion 19 that faces the opening 12a, and a plurality of second positioning portions 16d that face a second surface 19r on the outer surface of the protrusion 19 that faces the opposite side to the first surface 19p. The protrusion 19 is fixed to the inner surface of the groove 15 with an adhesive 90. Therefore, in the insertion step P2 of the fixing step Pf of fixing the second housing 18 to the first housing 12, in which the protrusion 19 is inserted into the groove 15, the first positioning portions 16a and the second positioning portions 16d can easily position the protrusion 19 along the center of the groove 15. As a result, in the curing step P3 of curing the uncured adhesive 90, the work of positioning the protrusion 19 along the center of the groove 15 using a positioning jig that determines the position of the second housing 18 relative to the first housing 12 in a direction intersecting the first direction D1 is not required. Therefore, in the present embodiment, since such a positioning jig is not required, an increase in equipment costs required for manufacturing the electric actuator 10 can be suppressed. Furthermore, since the protrusion 19 can be easily positioned along the center of the groove 15, an increase in the number of work steps in the fixing step Pf can be suppressed. Therefore, an increase in manufacturing costs of the electric actuator 10 can be suppressed.

[0090] Furthermore, in this embodiment, as described above, the positioning jig is not required in the curing step P3, so the number of electric actuators 10 that can be placed inside the heating furnace can be increased. This makes it possible to increase the number of electric actuators 10 whose uncured adhesive 90 can be cured by a single heating operation. Therefore, it is possible to prevent an increase in the number of manufacturing steps and manufacturing costs for the electric actuators 10.

[0091] Furthermore, in this embodiment, as described above, the positioning portions 16 allow the protrusion 19 to be positioned along the center of the groove 15, and therefore the outer surfaces of both the first surface 19p and the second surface 19r of the protrusion 19 can be fixed to the inner surface of the groove 15 with the adhesive 90. This increases the bonding area between the protrusion 19 and the inner surface of the groove 15, thereby suitably increasing the bonding strength between the first housing 12 and the second housing 18. This prevents the second housing 18 from coming off the first housing 12 even if vibrations from the motor unit 20 are transmitted to the second housing 18 during operation of the electric actuator 10. This effectively prevents moisture, dust, and the like from entering the housing 11, thereby suitably stabilizing the operation of the electric actuator 10.

[0092] According to the present embodiment, at least one of the multiple positioning portions 16 is in contact with the protrusion 19. As a result, as described above, the multiple positioning portions 16 allow the protrusion 19 to be positioned more accurately along the center of the groove 15. Therefore, the outer surfaces of both the first surface 19p and the second surface 19r of the protrusion 19 and the inner surface of the groove 15 can be more stably fixed with the adhesive 90, thereby more suitably increasing the adhesive strength between the first housing 12 and the second housing 18.

[0093] According to this embodiment, at least one first positioning portion 16a and at least one second positioning portion 16d each contact the protrusion 19. Therefore, compared to a case where none of the first positioning portions 16a contact the protrusion 19 or a case where none of the second positioning portions 16d contact the protrusion 19, the protrusion 19 can be positioned more accurately along the center of the groove 15. Therefore, the adhesive strength between the first housing 12 and the second housing 18 can be more suitably increased.

[0094] According to this embodiment, the first positioning portions 16a and the second positioning portions 16d are alternately provided along the extension direction of the groove portion 15. Therefore, the position of the protrusion 19 relative to the groove portion 15 can be determined alternately from the opening 12a side and the side opposite to the opening 12a side, and therefore the protrusion 19 can be positioned more accurately along the center of the groove portion 15. This can more suitably increase the adhesive strength between the first housing 12 and the second housing 18.

[0095] According to this embodiment, the groove 15 has a plurality of linear portions 15p that extend linearly when viewed from the first direction D1, and each of the linear portions 15p is provided with a first positioning portion 16a and a second positioning portion 16d. Therefore, compared to when each linear portion 15p is provided with only either the first positioning portion 16a or the second positioning portion 16d, the protrusion 19 can be positioned more accurately along the center of the groove 15 in each linear portion 15p. Therefore, the adhesive strength between each portion of the protrusion 19 and the inner surface of the groove 15 in each linear portion 15p can be increased, and the adhesive strength between the first housing 12 and the second housing 18 can be more suitably increased.

[0096] According to this embodiment, the upper side (+D1 side) of each of the positioning portions 16, i.e., the surfaces 16b, 16e facing one side in the first direction D1, are inclined surfaces that move downward (-D1 side), i.e., toward the other side in the first direction D1, toward the protruding portion 19. Therefore, as described above, in the insertion step P2, the upper-facing surfaces 16b, 16e of each positioning portion 16 can guide the protruding portion 19 to the center of the groove portion 15. This allows the protruding portion 19 to be easily inserted along the center of the groove portion 15, thereby preventing an increase in the number of steps in the insertion step P2. Therefore, an increase in the number of steps in manufacturing the electric actuator 10 can be more preferably prevented.

[0097] According to this embodiment, the dimension of the tip 19s of the protrusion 19, i.e., the portion of the protrusion 19 on the other side in the first direction D1, in the direction perpendicular to the extending direction of the protrusion 19 becomes smaller as it moves downward (towards the -D1 side). Therefore, as described above, in the insertion step P2, the tip 19s can be prevented from getting caught on each positioning portion 16, and the protrusion 19 can be easily inserted into the groove 15. This more effectively prevents an increase in the number of steps required for the insertion step P2. Therefore, it is more effectively prevents an increase in the number of steps required for manufacturing the electric actuator 10.

[0098] According to this embodiment, the electric actuator 10 includes an output shaft 39 that is rotatable about an output axis J4, a transmission mechanism 30 that is connected to the motor shaft 24 and the output shaft 39 and transmits the rotation of the motor shaft 24 to the output shaft 39, and a circuit board 70 that supplies current to the motor unit 20. The housing 11 accommodates the output shaft 39, the transmission mechanism 30, and the circuit board 70. Therefore, the transmission mechanism 30 can be disposed close to the motor unit 20 and the output shaft 39. This simplifies the configuration of the transmission mechanism 30. Furthermore, the circuit board 70 can be disposed close to the motor unit 20. This simplifies the configuration of the electric actuator 10, thereby preventing an increase in the manufacturing cost of the electric actuator 10.

[0099] Although the embodiments of the present invention have been described above, the configurations and combinations thereof in the embodiments are merely examples, and additions, omissions, substitutions, and other modifications of the configurations are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited to the embodiments.

[0100] The configuration of the transmission mechanism is not limited to this embodiment. For example, the transmission mechanism may not have either the first-stage gear or the second-stage gear. If the transmission mechanism does not have the first-stage gear, the rotation of the first gear can be transmitted to the output gear by connecting the second-stage gear to the first gear and the output gear. If the transmission mechanism does not have the second-stage gear, the rotation of the first gear can be transmitted to the output gear by connecting the first gear to the first gear and the output gear. The transmission mechanism may also have other components, such as an intermediate gear that transmits the rotation of the first-stage gear to the second-stage gear. If the intermediate gear is a stepped gear having multiple gear portions with different numbers of teeth, the degree of freedom in setting the reduction ratio of the rotation of the output shaft to the rotation of the motor shaft can be increased.

[0101] Furthermore, the upward-facing surfaces of the positioning portions do not have to be inclined surfaces that slope downward toward the protruding portion. In this case, the upward-facing surfaces of the positioning portions are perpendicular to the first direction. Even in this case, the protruding portion can be disposed along the center of the groove portion.

[0102] In addition, the dimension of the tip end in the first direction perpendicular to the direction in which the protrusion extends may be the same. Even in this case, the protrusion can be arranged along the center of the groove.

[0103] The application of the electric actuator to which the present invention is applied 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. Note that the configurations described above in this specification can be combined as appropriate within the scope of not mutually contradicting each other.

[0104] The present technology can be configured as follows. (1) An electric actuator comprising: a motor unit having a rotor rotatable around a motor axis; and a housing that accommodates the motor unit, wherein the housing comprises a first housing having an opening that opens to one side in a first direction; and a second housing that closes the opening and is fixed to the first housing, wherein the first housing has an annular groove that surrounds the opening and is recessed to the other side in the first direction, and a plurality of positioning portions that protrude from an inner surface of the groove in a direction intersecting the first direction, and the second housing has an annular protrusion that protrudes to the other side in the first direction and is disposed inside the groove, wherein the plurality of positioning portions include a plurality of first positioning portions that face a first surface of the outer surface of the protrusion that faces the opening side, and a plurality of second positioning portions that face a second surface of the outer surface of the protrusion that faces the opposite side from the first surface, and the protrusions are fixed to the inner surface of the groove with an adhesive. (2) The electric actuator according to (1), wherein at least one of the plurality of positioning portions is in contact with the protrusion. (3) The electric actuator according to (1) or (2), wherein at least one of the first positioning portions and at least one of the second positioning portions are in contact with the protrusion. (4) The electric actuator according to any one of (1) to (3), wherein the first positioning portions and the second positioning portions are alternately provided along the extending direction of the groove portions. (5) An electric actuator described in any one of (1) to (4), wherein the groove portion has a plurality of straight portions extending linearly when viewed from the first direction, and each of the plurality of straight portions is provided with the first positioning portion and the second positioning portion. (6) An electric actuator described in any one of (1) to (5), wherein the surface of each of the plurality of positioning portions facing one side of the first direction is an inclined surface that is positioned on the other side of the first direction as it approaches the protrusion. (7) An electric actuator described in any one of (1) to (6), wherein the portion of the protrusion on the other side in the first direction has a dimension in a direction perpendicular to the direction in which the protrusion extends that becomes smaller as the portion approaches the other side in the first direction. (8) An electric actuator described in any one of (1) to (7), comprising an output shaft rotatable around an output axis, a motor shaft of the rotor and a transmission mechanism connected to the output shaft and transmitting the rotation of the motor shaft to the output shaft, and a circuit board that supplies current to the motor section, wherein the housing accommodates the output shaft, the transmission mechanism, and the circuit board inside. [Explanation of symbols]

[0105] 10...electric actuator, 11...housing, 12...first housing, 12a...opening, 15...groove portion, 15p...straight portion, 16...positioning portion, 16a...first positioning portion, 16d...second positioning portion, 18...second housing, 19...protrusion portion, 19p...first surface, 19r...second surface, 20...motor portion, 22...rotor, 24...motor shaft, 30...transmission mechanism, 39...output shaft, 70...board, 90...adhesive, D1...first direction, J1...motor axis, J4...output axis

Claims

1. a motor unit having a rotor that can rotate around a motor axis; and a housing that accommodates the motor unit therein; The housing includes: a first housing having an opening that opens to one side in a first direction; a second housing that closes the opening and is fixed to the first housing; and The first housing includes: an annular groove portion that surrounds the opening and is recessed to the other side in the first direction; a plurality of positioning portions protruding from an inner surface of the groove portion in a direction intersecting the first direction; and the second housing has an annular protrusion that protrudes toward the other side in the first direction and is disposed inside the groove, the plurality of positioning portions include a plurality of first positioning portions opposed to a first surface of the outer surface of the protrusion that faces the opening side, and a plurality of second positioning portions opposed to a second surface of the outer surface of the protrusion that faces the opposite side to the first surface, The protrusion is fixed to the inner surface of the groove with an adhesive.

2. The electric actuator according to claim 1 , wherein at least one of the positioning portions is in contact with the protrusion.

3. The electric actuator according to claim 1 , wherein each of the at least one first positioning portion and the at least one second positioning portion is in contact with the protrusion.

4. The electric actuator according to claim 1 , wherein the first positioning portions and the second positioning portions are provided alternately along a direction in which the grooves extend.

5. The groove portion has a plurality of linear portions that extend linearly when viewed from the first direction, The electric actuator according to claim 1 , wherein each of the plurality of linear portions is provided with the first positioning portion and the second positioning portion.

6. The electric actuator according to claim 1 , wherein the surface of each of the positioning portions facing one side in the first direction is an inclined surface that is positioned toward the other side in the first direction as it approaches the protrusion.

7. The electric actuator according to claim 1 , wherein the portion of the protrusion on the other side in the first direction has a dimension in a direction perpendicular to the direction in which the protrusion extends that becomes smaller as the portion approaches the other side in the first direction.

8. an output shaft rotatable about an output axis; a transmission mechanism connected to a motor shaft of the rotor and the output shaft, for transmitting rotation of the motor shaft to the output shaft; a substrate for supplying current to the motor unit; Equipped with The electric actuator according to claim 1 , wherein the housing accommodates the output shaft, the transmission mechanism, and the circuit board therein.

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