Shift device

Abstract

To provide a shift device capable of improving assemblability of a driving force mechanism.SOLUTION: A shift device 100 comprises an actuator 1 that drives a shift switching member 20. The actuator 1 includes: a motor 10 provided with a motor gear 10e; a driving force transmission mechanism 3 having a plurality of transmission gears 30 that transmits the driving force of the motor gear 10e to an output shaft 4b that outputs the driving force to the outside of the actuator 1, and a central shaft 31 of the transmission gear 30; an external housing 5 that houses the motor 10 and the driving force transmission mechanism 3; and an inner lid 6 that is housed inside the external housing 5, and to which the motor 10 and the driving force transmission mechanism 3 are attached, where one end 310 of the central shaft 31 is fixed to the inner lid 6, and the driving force transmission mechanism 3 separates from the external housing 5.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a shift device, and more particularly to a shift device including an actuator that drives a shift switching member.

Background Art

[0002] Conventionally, a shift device including an actuator that drives a shift switching member has been known (see, for example, Patent Document 1).

[0003] Patent Document 1 discloses a shift device including a shift switching member having a plurality of valleys corresponding to shift positions and an actuator that drives the shift switching member using the driving force of a motor. The actuator includes a driving force transmission mechanism for transmitting the driving force of the motor to the shift switching member, an inner lid to which the motor is attached, and a housing that covers the driving force transmission mechanism and the inner lid from the outside. The driving force transmission mechanism has a central axis provided with a plurality of gear portions. The driving force transmission mechanism is disposed at a position where the central axis straddles both the inner lid and the housing, and is disposed at a position sandwiched between both the inner lid and the housing and in contact with both the inner lid and the housing.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the shift device of Patent Document 1 described above, when assembling the driving force transmission mechanism, it is necessary to arrange the central axis at a position straddling both the middle cover and the housing, and to arrange the driving force transmission mechanism at a position sandwiched between both the middle cover and the housing and in contact with both the middle cover and the housing. In this case, when assembling the driving force transmission mechanism, the mutual positions of the middle cover and the housing must be considered, and it is difficult to assemble the driving force transmission mechanism. Therefore, it is required to improve the assemblability of the driving force transmission mechanism.

[0006] The present invention has been made to solve the above problems, and one object of the present invention is to provide a shift device capable of improving the assemblability of a driving force transmission mechanism.

Means for Solving the Problems

[0007] To achieve the above object, a shift device according to one aspect of the present invention includes an actuator that drives a shift switching member. The actuator includes a motor provided with a motor gear, a plurality of transmission gears that transmit the driving force of the motor gear to an output shaft that outputs the driving force to the outside of the actuator, and a driving force transmission mechanism having a central axis of the transmission gear, an external housing that houses the motor and the driving force transmission mechanism, and a middle cover that is housed inside the external housing and to which the motor and the driving force transmission mechanism are attached. One end of the central axis is fixed to the middle cover, and the driving force transmission mechanism is separated from the external housing.

[0008] In the shift device according to one aspect of the present invention, as described above, a driving force transmission mechanism having a central axis of a plurality of transmission gears that transmits the driving force of the motor gear to the output shaft, and an inner lid that is housed inside the outer housing and to which the motor and the driving force transmission mechanism are attached are provided. One end of the central axis is fixed to the inner lid, and the driving force transmission mechanism is separated from the outer housing. As a result, unlike the conventional case where the central axis is arranged at a position straddling both the inner lid and the outer housing, it is possible to eliminate the need to assemble the driving force transmission mechanism to both the inner lid and the outer housing in consideration of the mutual positions of the inner lid and the outer housing. That is, since the driving force transmission mechanism can be configured to be assembled to the inner lid without being assembled to the outer housing, it is not necessary to consider the mutual positions of the inner lid and the outer housing when assembling the driving force transmission mechanism, and the assemblability of the driving force transmission mechanism can be improved.

[0009] In the shift device according to the above aspect, preferably, the central axis has a first central axis and a second central axis arranged parallel to each other, and the driving force transmission mechanism connects the other ends of the first central axis and the second central axis to each other, and includes a retaining member that regulates the movement of the transmission gear with respect to the first central axis and the second central axis so that the transmission gear does not come off from the first central axis and the second central axis.

[0010] With this configuration, since the other ends of the first central axis and the second central axis can be connected to each other by the retaining member, the distance between the other ends can be accurately maintained. In addition, it is possible to prevent the transmission gear from coming off from each of the first central axis and the second central axis by the retaining member.

[0011] In this case, preferably, the retaining member is a plate member having two hole portions into which the other end of the first central axis and the other end of the second central axis are inserted, and the two hole portions include press-fitting hole portions into which at least one of the other end of the first central axis and the other end of the second central axis is press-fitted.

[0012] With such a configuration, by means of the plate member having a simple structure, at least one of the other ends of the first central axis and the other end of the second central axis can be press-fitted into the press-fitting hole portion, and the other end of the first central axis and the other end of the second central axis can be connected. Therefore, the distance between the other ends of the first central axis and the second central axis can be accurately maintained, and it is possible to avoid the transmission gear coming off from each of the first central axis and the second central axis.

[0013] In the shift device according to the above aspect, preferably, the actuator includes a control board for controlling a motor, the control board is attached to the middle cover, the middle cover has a driving force transmission mechanism attached from one side in the axial direction of the central axis, and the control board and the motor are attached from the other side in the axial direction. The external housing has a housing main body that covers the middle cover from one side in the axial direction in a state of being separated from the driving force transmission mechanism, and a cover member that covers the middle cover from the other side in the axial direction in a state of being separated from the control board and the motor.

[0014] With such a configuration, the control board, the motor, and the driving force transmission mechanism can be integrated into the middle cover and separated from the housing main body and the cover member, so that the assemblability of the middle cover, the housing main body, and the cover member in which the control board, the motor, and the driving force transmission mechanism are integrated can be improved.

[0015] In addition, in the shift device according to the above aspect, the following configurations are also conceivable.

[0016] (Additional item 1) In the configuration in which the retaining member has a press-fitting hole portion, the two hole portions include a press-fitting hole portion into which one of the other ends of the first central axis and the other end of the second central axis is press-fitted, and the other of the other ends of the first central axis and the second central axis is inserted, and an elongated long hole portion along the arrangement direction of the first central axis and the second central axis.

[0017] With such a configuration, in the arrangement direction of the first central axis and the second central axis, the elongated hole portion can avoid the mutual restraint by the retaining members of the first central axis and the second central axis, so that the stress strain applied to the first central axis and the second central axis can be reduced.

[0018] (Additional item 2) In the above shift device, preferably, the middle cover is formed of a metal material.

[0019] With such a configuration, the rigidity of the middle cover can be improved. As a result, the resistance of the middle cover to vibration can be improved. In addition, the positional accuracy of each component including the driving force transmission mechanism assembled to the middle cover can be enhanced.

[0020] (Additional item 3) In the configuration where the above driving force transmission mechanism includes a retaining member, preferably, the driving force transmission mechanism includes a first bearing provided on the first central axis and supporting the transmission gear, and a second bearing provided on the second central axis and supporting the transmission gear, and the retaining member abuts against the first bearing and the second bearing from the external housing side to restrict the movement of the first bearing and the second bearing to the external housing side.

[0021] With such a configuration, by restricting the movement of the first bearing and the second bearing to the external housing side by the retaining member, it is possible to avoid the transmission gear supported by the first bearing and the second bearing, and the first bearing and the second bearing from coming off the first central axis and the second central axis.

[0022] (Additional item 4) In the configuration where the above retaining member is a plate member, preferably, the middle cover has a first press-fitting hole into which one end of the first central axis is press-fitted, and a second press-fitting hole into which one end of the second central axis is press-fitted, and the center-to-center distance between the two hole portions of the plate member is substantially equal to the center-to-center distance between the first press-fitting hole and the second press-fitting hole of the middle cover.

[0023] With such a configuration, by simply press-fitting the first central axis and the second central axis into the first press-fitting hole and the second press-fitting hole respectively, the center-to-center distance between the first central axis and the second central axis at each position in the axial direction can be kept constant. Also, the first central axis and the second central axis can be easily fixed to each of the first press-fitting hole and the second press-fitting hole by press-fitting.

Effect of the Invention

[0024] The present invention can improve the assemblability of the driving force transmission mechanism.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0026] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0027] With reference to FIGS. 1 to 5, the configuration of a shift device 100 mounted on a vehicle such as an electric vehicle will be described.

[0028] As shown in FIGS. 1 and 2, in a vehicle, when an occupant (driver) performs a shift switching operation via an operation unit such as a shift lever (or a shift switch), electrical shift switching control for a transmission mechanism unit is performed. That is, the position of the shift lever is input to the shift device 100 via a shift sensor provided in the operation unit. Then, based on a control signal transmitted from a dedicated control board 11 provided in the shift device 100, the transmission mechanism unit can be switched to any one of the shift positions of P (parking) position, R (reverse) position, N (neutral) position, and D (drive) position corresponding to the shift operation of the occupant. Such shift switching control is called shift-by-wire. Note that each of the P, R, N, and D positions is an example of the "shift position" in the claims.

[0029] The shift device 100 includes an actuator 1 and a shift switching mechanism 2 (see FIG. 5) including a shift switching member 20 (see FIG. 5). The actuator 1 is a driving device that drives the shift switching member 20 based on a shift switching operation of an occupant (driver).

[0030] Here, in each figure, the axial directions of a first central axis 31a and a second central axis 31b of a driving force transmission mechanism 3 of the actuator 1, which will be described later, are indicated by the Z direction. One of the Z directions is indicated by the Z2 direction, and the other is indicated by the Z1 direction. Also, the direction orthogonal to the Z direction is indicated by the A direction.

[0031] As shown in FIG. 1, the actuator 1 includes a motor 10, a control board 11, a driving force transmission mechanism 3, an output gear 4a and an output shaft 4b, an external housing 5 having a housing main body 50 and a lid member 51, an intermediate lid 6, a plate member 7, and a connection terminal 8. The plate member 7 is included in the components of the driving force transmission mechanism 3. Note that the plate member 7 is an example of the "anti-disengagement member" in the claims.

[0032] Here, in the present embodiment, a central shaft 31 (a first central shaft 31a and a second central shaft 31b), which will be described later in the driving force transmission mechanism 3, is configured as a cantilever shaft with one end 310 (the end on the Z1 direction side) fixed to the middle cover 6. The other end 311 (the end on the Z2 direction side) of the central shaft 31 is a free end. Details will be described later.

[0033] (Configuration of the motor) The motor 10 is an IPM (Interior Permanent Magnet) type brushless three-phase motor. The motor 10 is fixed to the middle cover 6 by a fastening member. The motor 10 includes a rotor 10a, a stator 10b, a shaft 10c, a magnet 10d, and a motor gear 10e having external teeth.

[0034] Inside the rotor 10a, N-pole magnets and S-pole magnets as permanent magnets are alternately embedded at equal angular intervals around the rotation axis C1 of the shaft 10c. The stator 10b has a plurality of phases (U phase, V phase, and W phase) of exciting coils that generate magnetic force when energized. The shaft 10c is configured to rotate around the rotation axis C1 together with the rotor 10a. The shaft 10c is rotatably supported by the middle cover 6. The magnet 10d is attached to the shaft 10c to detect the rotational angular position of the shaft 10c. The magnet 10d is disposed at the end of the shaft 10c on the Z1 direction side. The motor gear 10e is provided at the end of the shaft 10c on the Z2 direction side.

[0035] (Configuration of the control board) The control board 11 shown in FIG. 1 is configured to control the motor 10. The control board 11 is a board component with electronic components mounted on the board. The control board 11 is fixed to the middle cover 6 by fastening members. On the control board 11, a rotation angle sensor 11a is arranged at a position facing the magnet 10d in the extending direction of the shaft 10c. The rotation angle sensor 11a is a sensor that detects the rotation amount (rotation angle) of the shaft 10c by the magnet 10d attached to the shaft 10c. The rotation angle sensor 11a is arranged at a position facing the magnet 10d in the Z direction. That is, the magnet 10d and the rotation angle sensor 11a are arranged on the rotation axis C1 of the shaft 10c with a predetermined gap therebetween.

[0036] The control board 11 has an insertion hole 11b (see FIG. 2), an insertion hole 11c (see FIG. 2), and a plurality of fitting holes 11d. The insertion hole 11b, the insertion hole 11c, and the plurality of fitting holes 11d are through holes that penetrate the board in the Z direction. The tip of the Z1-direction side of the connection terminal 8 is inserted into each of the plurality of fitting holes 11d so as to fit.

[0037] (Configuration of the driving force transmission mechanism) The driving force transmission mechanism 3 is separated from the external housing 5. The driving force transmission mechanism 3 is connected to the shaft 10c and is configured to transmit the driving force from the motor 10 to the output shaft 4b. The driving force transmission mechanism 3 is configured as a speed reduction mechanism that reduces the speed before the driving force of the motor 10 is output from the output shaft 4b. The driving force transmission mechanism 3 has a plurality of transmission gears 30 that transmit the driving force of the motor gear 10e to the output shaft 4b, a central axis 31 of the transmission gear 30, and a first bearing 32a and a second bearing 32b.

[0038] The transmission gear 30 is composed of spur gears. The transmission gear 30 has a first transmission gear 30a, a second transmission gear 30b, a third transmission gear 30c, and a fourth transmission gear 30d. The central axis 31 has a first central axis 31a and a second central axis 31b that are arranged parallel to each other. That is, the central axis line C2 of the first central axis 31a and the central axis line C3 of the second central axis 31b are parallel. The first central axis 31a and the second central axis 31b extend in the Z direction.

[0039] Here, the driving force from the motor gear 10e is transmitted in the order of the first transmission gear 30a, the second transmission gear 30b, the third transmission gear 30c, the fourth transmission gear 30d, the output gear 4a, the output shaft 4b, and the shift switching mechanism 2.

[0040] The first transmission gear 30a and the second transmission gear 30b are inserted through the first central axis 31a. The first transmission gear 30a is configured to mesh with the motor gear 10e and be driven by the motor gear 10e. The second transmission gear 30b is arranged adjacent to the Z2 direction side of the first transmission gear 30a. The second transmission gear 30b is provided integrally with the first transmission gear 30a and is configured to rotate together with the first transmission gear 30a.

[0041] The first bearing 32a is provided on the first central axis 31a and supports the first transmission gear 30a and the second transmission gear 30b. Specifically, the first bearing 32a supports the first transmission gear 30a and the second transmission gear 30b in a rotatable state about the central axis line C2. The first bearing 32a is arranged between the first transmission gear 30a and the second transmission gear 30b and the first central axis 31a in the radial direction. The other end 311 (the end in the Z2 direction) of the first central axis 31a is spaced apart from the inner surface of the housing body 50 with a slight gap in the axial direction (Z direction).

[0042] The first bearing 32a is provided one between the end face of the first transmission gear 30a in the Z1 direction and the middle cover 6 in the axial direction (Z direction). Also, the first bearing 32a is provided one between the end face of the second transmission gear 30b in the Z2 direction and the plate member 7 in the axial direction (Z direction). In short, the first bearing 32a is a pair of structures facing each other in the axial direction (Z direction).

[0043] The third transmission gear 30c and the fourth transmission gear 30d are inserted through the second central shaft 31b. The third transmission gear 30c is configured to mesh with the second transmission gear 30b and be driven by the second transmission gear 30b. The fourth transmission gear 30d is disposed adjacent to the Z1-direction side of the third transmission gear 30c. The fourth transmission gear 30d is integrally provided with respect to the third transmission gear 30c and is configured to rotate together with the third transmission gear 30c.

[0044] The second bearing 32b is provided on the second central shaft 31b and supports the third transmission gear 30c and the fourth transmission gear 30d. Specifically, the second bearing 32b supports the third transmission gear 30c and the fourth transmission gear 30d in a rotatable state about the central axis C3. The second bearing 32b is disposed between the third transmission gear 30c and the fourth transmission gear 30d and the second central shaft 31b in the radial direction. The other end 311 (the end in the Z2 direction) of the second central shaft 31b is spaced apart from the inner surface of the housing body 50 with a slight gap in the axial direction (Z direction).

[0045] The second bearing 32b is provided one between the end face of the third transmission gear 30c in the Z2 direction and the plate member 7 in the axial direction (Z direction). Also, the second bearing 32b is provided one between the end face of the fourth transmission gear 30d in the Z1 direction and the middle cover 6 in the axial direction (Z direction). In short, the second bearing 32b is a pair of structures facing each other in the axial direction (Z direction). The end face on the Z2-direction side of the second bearing 32b is disposed slightly shifted to the Z1-direction side from the first bearing 32a.

[0046] One end 310 on the Z1 direction side (the middle cover 6 side) of the first central axis 31a is press-fitted into a first press-fitting hole 6a provided in the middle cover 6. For this reason, the central axis C2 of the first central axis 31a is configured so as not to incline (so as to maintain a parallel state) with respect to the rotation axis C1 of the shaft 10c.

[0047] One end 310 on the Z1 direction side (the middle cover 6 side) of the second central axis 31b is press-fitted into a second press-fitting hole 6b provided in the middle cover 6. For this reason, the central axis C3 of the second central axis 31b is configured so as not to incline (so as to maintain a parallel state) with respect to the rotation axis C1 of the shaft 10c.

[0048] (Configuration of output gear and output shaft) The output shaft 4b is a shaft for outputting the driving force of the motor 10 to the outside of the actuator 1. The output gear 4a is a fan-shaped gear. The output gear 4a is a so-called sector gear. The output gear 4a is configured to mesh with the fourth transmission gear 30d and be driven (rotated) by the fourth transmission gear 30d. An output shaft 4b extending in the Z direction is provided on the output gear 4a. The output shaft 4b is configured to rotate together with the fan-shaped output gear 4a.

[0049] The output shaft 4b is rotatably supported by the middle cover 6 and the outer housing 5 (housing body 50). The output shaft 4b extends from the inside of the outer housing 5 to the outside so that the end on the Z2 direction side protrudes downward from the outer housing 5. A shift switching member 20 is fixed to the end on the Z2 direction side of the output shaft 4b. Therefore, the output shaft 4b is configured to rotate together with the shift switching member 20. The output shaft 4b has a rotation axis C4 parallel to the Z direction.

[0050] (Configuration of outer housing) As shown in FIGS. 1 and 2, the external housing 5 has a housing main body 50 and a lid member 51. The external housing 5 houses the motor 10 and the driving force transmission mechanism 3. Specifically, the housing main body 50 and the lid member 51 constitute a housing space for housing the motor 10, the control board 11, and the driving force transmission mechanism 3.

[0051] The housing main body 50 has a concave shape in which the surface on the Z1 direction side is recessed toward the Z2 direction side. Specifically, the housing main body 50 has an inner bottom surface 50a and an inner side surface 50b extending from the inner bottom surface 50a. The inner bottom surface 50a is the bottom surface of the concave shape formed on the surface on the Z1 direction side of the housing main body 50. The inner side surface 50b is a side surface extending from the edge of the inner bottom surface 50a toward the Z1 direction side.

[0052] The inner bottom surface 50a has a plate accommodation space 52 for the plate member 7. The plate accommodation space 52 has a shape in which the outer surface of the plate member 7 is offset outward. In short, the inner bottom surface 50a forming the plate accommodation space 52 is separated from the plate member 7 by a predetermined distance.

[0053] The housing main body 50 has a positioning convex portion 150 on the inside. The positioning convex portion 150 protrudes toward the Z1 direction side. The positioning convex portion 150 has a substantially frustum shape. The positioning convex portion 150 is inserted into an insertion hole 62 (see FIG. 2) of the middle lid 6 described later to position the middle lid 6 in a direction orthogonal to the Z direction. Also, it is inserted into an insertion hole 11b (see FIG. 2) of the control board 11 to position the control board 11 in a direction orthogonal to the Z direction. Further, the positioning convex portion 150 has a surface for placing the control board 11 and positioning the control board 11 in the Z direction.

[0054] The lid member 51 is disposed on the Z1 direction side of the housing main body 50. The lid member 51 has a concave shape in which the surface on the Z2 direction side is recessed toward the Z1 direction side. The lid member 51 is a cover that covers the housing main body 50 from the Z1 direction side.

[0055] The housing body 50 and the lid member 51 are resin members. The housing body 50 and the lid member 51 are joined by welding. That is, a welded portion is provided between the lid member 51 and the housing body 50 to suppress the intrusion of foreign matter into the accommodation space surrounded by the lid member 51 and the housing body 50.

[0056] The housing body 50 covers the middle lid 6 from one axial side (Z2 direction side) in a state of being separated from the driving force transmission mechanism 3. The lid member 51 covers the middle lid 6 from the other axial side (Z1 direction side) in a state of being separated from the control board 11 and the motor 10.

[0057] (Configuration of the middle lid) As shown in FIGS. 1 and 2, the middle lid 6 is accommodated inside the outer housing 5. The middle lid 6 is disposed between the driving force transmission mechanism 3 and the control board 11 in the Z direction. The middle lid 6 to which one end 310 of the central axis 31 is fixed in a cantilevered shaft shape is formed of a metal material. Although it is an example, the middle lid 6 is a molded product made of aluminum formed by die casting as a raw material.

[0058] The middle lid 6 is attached to the housing body 50. The middle lid 6 is separated from the lid member 51 without contacting the lid member 51.

[0059] The driving force transmission mechanism 3 is attached to the middle lid 6 from one side (Z2 direction) in the axial direction of the central axis 31, and the motor 10 and the control board 11 are attached from the other side (Z1 direction) in the axial direction. The middle lid 6 partitions the accommodation space into one space on the Z1 direction side that accommodates the motor 10 and the control board 11 and the other space on the Z2 direction side that accommodates the driving force transmission mechanism 3.

[0060] At least the control board 11 is fixed to the surface on the Z1 direction side (the surface on the lid member 51 side) of the middle lid 6.

[0061] The middle cover 6 has a positioning convex portion 60 that is inserted into the insertion hole 11c of the control board 11. The positioning convex portion 60 protrudes toward the Z1 direction side. The positioning convex portion 60 positions the control board 11 in a direction orthogonal to the Z direction.

[0062] Further, the middle cover 6 has a plurality of boss portions 61 (see FIG. 2) to which fastening members for fixing the control board 11 are attached. A fastening member is screwed into the boss portion 61, and the control board 11 is fixed to the middle cover 6.

[0063] Further, the middle cover 6 has an insertion hole 62 (see FIG. 2) into which the positioning convex portion 150 of the housing main body 50 is inserted. The insertion hole 62 is a through hole that penetrates the middle cover 6 in the Z direction.

[0064] Also, as described above, the first central axis 31a and the second central axis 31b of the driving force transmission mechanism 3 are press-fitted and fixed to the first press-fitting hole 6a and the second press-fitting hole 6b of the middle cover 6, respectively. Specifically, the middle cover 6 has a first press-fitting hole 6a and a second press-fitting hole 6b. The first press-fitting hole 6a and the second press-fitting hole 6b are recessed from the surface on the Z2 direction side of the middle cover 6 toward the Z1 direction side. In a direction (A direction) orthogonal to the Z direction, the first press-fitting hole 6a is disposed closer to the shaft 10c of the motor 10 than the second press-fitting hole 6b. Also, in a direction (A direction) orthogonal to the Z direction, the second press-fitting hole 6b is disposed closer to the output shaft 4b than the first press-fitting hole 6a. Each shape of the first press-fitting hole 6a and the second press-fitting hole 6b may be either a through hole or a concave hole.

[0065] The first press-fitting hole 6a, the second press-fitting hole 6b, and various holes for fixing and positioning of the middle cover 6 are not formed by the above die casting, but are formed in the middle cover 6 by cutting processes performed on the molded product after die casting.

[0066] As shown in FIG. 4, the connection terminal 8 connects the control device as an external device and the control board 11 via the middle cover 6. The connection terminal 8 is a bus bar that connects the control device and the control board 11. The connection terminal 8 is made of metal. In this way, the connection terminal 8 electrically connects the control device and the control board 11 by being electrically connected to the wiring cable.

[0067] (Configuration of the plate member) As shown in FIGS. 1, 3, and 4, the plate member 7 connects the other ends 311 (the ends on the Z2 direction side) which are the free ends of the first central axis 31a and the second central axis 31b respectively, so that the transmission gear 30 does not come off from the first central axis 31a and the second central axis 31b, and restricts the movement of the transmission gear 30 with respect to the first central axis 31a and the second central axis 31b. The plate member 7 is formed of a metal material. The plate member 7 is a plate member with the Z direction as the thickness direction. The plate member 7 extends in the arrangement direction of the first central axis 31a and the second central axis 31b in the A direction which is a direction orthogonal to the Z direction. The plate member 7 has two hole portions 7a into which the other end 311 of the first central axis 31a and the other end 311 of the second central axis 31b are press-fitted. Each shape of the two hole portions 7a may be either a through hole or a concave hole.

[0068] The two holes 7a include a press-fitting hole 70 into which the other end 311 of the first central axis 31a is press-fitted, and a long hole 71 into which the other end 311 of the second central axis 31b is inserted and which is elongated along the alignment direction of the first central axis 31a and the second central axis 31b (the longitudinal direction of the plate member 7). The press-fitting hole 70 is formed in a circular shape. The long hole 71 is formed to be slightly larger than the second central axis 31b or substantially the same size as the second central axis 31b in the short-side direction of the plate member 7. Note that the above-mentioned "longitudinal direction of the plate member 7" is the direction along the A direction. Also, the above-mentioned "short-side direction of the plate member 7" is the direction orthogonal to both the longitudinal direction and the thickness direction (Z direction) of the plate member 7. The long hole 71 is composed of a pair of opposing straight portions and two arc portions connecting the ends of the pair of straight portions in a plan view (viewed from the Z direction). Note that the plate member 7 is spaced apart from the external housing 5.

[0069] The plate member 7 has a semi-circular arc portion 7b centered on the first central axis 31a at one end in the A direction and a semi-circular arc portion 7b centered on the second central axis 31b at the other end in the A direction. The plate member 7 has a step portion 7c for absorbing a slight deviation in the Z direction between the first bearing 32a and the second bearing 32b. The step portion 7c is disposed between the two holes 7a.

[0070] The plate member 7 abuts against the first bearing 32a and the second bearing 32b from the external housing side (Z2 direction side) to restrict the movement of the first bearing 32a and the second bearing 32b toward the external housing 5. Specifically, the plate member 7 abuts against the ends of the first bearing 32a and the second bearing 32b in the Z2 direction to restrict the movement of the first bearing 32a and the second bearing 32b in the Z2 direction. In short, the plate member 7 has a function of preventing the transmission gear 30 of the driving force transmission mechanism 3 from coming off the first central axis 31a and the second central axis 31b.

[0071] Furthermore, the plate member 7 has a function of maintaining the center distance between the first central axis 31a and the second central axis 31b in a cantilever shaft shape.

[0072] Here, as shown in FIG. 1, the distance L1 between the centers of the first press-fitting hole 6a and the second press-fitting hole 6b of the inner lid is substantially equal to the distance L2 between the centers of the two hole portions 7a of the plate member 7. Therefore, in the entire axial direction (Z direction) of the cantilevered first central axis 31a and the second central axis 31b, the distance between the centers of the first central axis 31a and the second central axis 31b is maintained substantially constant. Therefore, it is constantly maintained so that the distance between the motor gear 10e and the first transmission gear 30a that mesh with each other does not change. Also, it is constantly maintained so that the distance between the fourth transmission gear 30d and the output gear 4a that mesh with each other does not change.

[0073] (Shift switching mechanism) As shown in FIG. 5, the shift switching mechanism 2 is connected to a manual spool valve (not shown) of a hydraulic valve body in a hydraulic control circuit section (not shown) in a transmission mechanism section (not shown) and a parking mechanism section (not shown). The transmission mechanism section is configured such that when the shift switching mechanism 2 is driven, the shift state (P position, R position, N position, and D position) is mechanically switched.

[0074] The shift switching mechanism 2 includes the shift switching member 20 and a positioning member 21 having a pin 21a. The shift switching member 20 is a detent plate. The shift switching member 20 has a plurality (four) of valley portions 20a provided corresponding to the shift positions (P position, R position, N position, and D position). The positioning member 21 is configured to establish a shift position in a state where the pin 21a is fitted into any one of the plurality of valley portions 20a of the shift switching member 20 that rotates by driving of the actuator 1. The positioning member 21 is a detent spring. The positioning member 21 is configured to hold the detent plate at a rotational angle position corresponding to the shift positions (P position, R position, N position, and D position).

[0075] (Effects of this embodiment) In this embodiment, the following effects can be obtained.

[0076] In this embodiment, as described above, there is provided an actuator 1 including a driving force transmission mechanism 3 having a central axis 31 of a plurality of transmission gears 30 that transmit the driving force of the motor gear 10e to the output shaft 4b, and an inner lid 6 that is housed inside the outer housing 5 and to which the motor 10 and the driving force transmission mechanism 3 are attached. One end 310 of the central axis 31 is fixed to the inner lid 6, and the driving force transmission mechanism 3 is spaced apart from the outer housing 5. Thus, unlike the case of arranging the central axis as in the prior art at a position straddling both the inner lid and the outer housing, it is possible to eliminate the need to assemble the driving force transmission mechanism 3 to both the inner lid 6 and the outer housing 5 in consideration of the mutual positions of the inner lid 6 and the outer housing 5. That is, since the driving force transmission mechanism 3 can be configured to be assembled to the inner lid 6 without being assembled to the outer housing 5, there is no need to consider the mutual positions of the inner lid 6 and the outer housing 5 when assembling the driving force transmission mechanism 3, and the assemblability of the driving force transmission mechanism 3 can be improved.

[0077] In this embodiment, as described above, the central axis 31 has a first central axis 31a and a second central axis 31b that are arranged parallel to each other, and the driving force transmission mechanism 3 includes a retaining member (plate member 7) that connects the other ends 311 of the first central axis 31a and the second central axis 31b to each other and restricts the movement of the transmission gear 30 with respect to the first central axis 31a and the second central axis 31b so that the transmission gear 30 does not come off from the first central axis 31a and the second central axis 31b. Thus, the retaining member (plate member 7) can connect the other ends 311 of the first central axis 31a and the second central axis 31b to each other, so that the distance between the other ends 311 can be accurately maintained. Further, the retaining member (plate member 7) can prevent the transmission gear 30 from coming off from each of the first central axis 31a and the second central axis 31b.

[0078] In this embodiment, as described above, the retaining member is a plate member 7 having two hole portions 7a into which the other ends 311 of the first central axis 31a and the second central axis 31b are inserted. The two hole portions 7a include press-fitting hole portions 70 into which at least one of the other ends 311 of the first central axis 31a and the second central axis 31b is press-fitted. Thus, with the plate member having a simple configuration, at least one of the other ends 311 of the first central axis 31a and the second central axis 31b is press-fitted into the press-fitting hole portion 70, and the other end 311 of the first central axis 31a and the other end 311 of the second central axis 31b can be connected. Therefore, the distance between the other ends 311 of the first central axis 31a and the second central axis 31b can be accurately maintained, and the transmission gear 30 can be prevented from coming off from each of the first central axis 31a and the second central axis 31b.

[0079] In this embodiment, as described above, the actuator 1 includes a control board 11 that controls the motor 10. The control board 11 is attached to the middle cover 6. The middle cover 6 has the driving force transmission mechanism 3 attached thereto from one side in the axial direction of the central axis 31, and the control board 11 and the motor 10 attached thereto from the other side in the axial direction. The external housing 5 has a housing body 50 that covers the middle cover 6 from one side in the axial direction in a state of being separated from the driving force transmission mechanism 3, and a lid member 51 that covers the middle cover 6 from the other side in the axial direction in a state of being separated from the control board 11 and the motor 10. Thus, the control board 11, the motor 10, and the driving force transmission mechanism 3 can be integrated on the middle cover 6 and separated from the housing body 50 and the lid member 51, so that the assemblability of the middle cover 6, the housing body 50, and the lid member 51 in which the control board 11, the motor 10, and the driving force transmission mechanism 3 are integrated can be improved.

[0080] In this embodiment, as described above, the two hole portions 7a include a press-fitting hole portion 70 into which one of the other ends 311 of the first central axis 31a and the other end 311 of the second central axis 31b is press-fitted, and the other of the other ends 311 of the first central axis 31a and the other end 311 of the second central axis 31b is inserted, and an elongated long hole portion 71 along the alignment direction of the first central axis 31a and the second central axis 31b. Thereby, in the alignment direction of the first central axis 31a and the second central axis 31b, the long hole portion 71 can avoid the mutual restraint by the retaining member (plate member 7) of the first central axis 31a and the second central axis 31b, so that the stress strain applied to the first central axis 31a and the second central axis 31b can be reduced.

[0081] In this embodiment, as described above, the middle lid 6 is formed of a metal material. Thereby, the rigidity of the middle lid 6 can be improved. As a result, the resistance of the middle lid 6 to vibration can be improved. In addition, the positional accuracy of each component including the driving force transmission mechanism 3 assembled to the middle lid 6 can be enhanced.

[0082] In this embodiment, as described above, the driving force transmission mechanism 3 includes a first bearing 32a provided on the first central axis 31a and supporting the transmission gear 30, and a second bearing 32b provided on the second central axis 31b and supporting the transmission gear 30. The retaining member (plate member 7) abuts against the first bearing 32a and the second bearing 32b from the external housing 5 side to restrict the movement of the first bearing 32a and the second bearing 32b to the external housing 5 side. Thereby, by restricting the movement of the first bearing 32a and the second bearing 32b to the external housing 5 side by the retaining member (plate member 7), the transmission gear 30 supported by the first bearing 32a and the second bearing 32b, and the first bearing 32a and the second bearing 32b can be prevented from coming off the first central axis 31a and the second central axis 31b.

[0083] In this embodiment, as described above, the middle lid 6 has a first press-fitting hole 6a into which one end 310 of the first central axis 31a is press-fitted, and a second press-fitting hole 6b into which one end 310 of the second central axis 31b is press-fitted. The center-to-center distance between the two hole portions 7a of the plate member is substantially equal to the distance between the first press-fitting hole 6a and the second press-fitting hole 6b of the middle lid 6. Accordingly, by simply press-fitting the first central axis 31a and the second central axis 31b into the first press-fitting hole 6a and the second press-fitting hole 6b, respectively, the distance between the first central axis 31a and the second central axis 31b at each position in the axial direction can be kept constant. Further, the first central axis 31a and the second central axis 31b can be easily fixed to the first press-fitting hole 6a and the second press-fitting hole 6b, respectively, by press-fitting.

[0084] [Modification Example] The disclosed embodiment should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is shown not by the description of the above embodiment but by the claims, and further includes all changes (modification examples) within the meaning and scope equivalent to the claims.

[0085] For example, in the above embodiment, an example in which the driving force transmission mechanism includes two central axes is shown, but the present invention is not limited to this. In the present invention, the driving force transmission mechanism may include only one central axis or three or more central axes.

[0086] Further, in the above embodiment, an example in which the driving force transmission mechanism includes four transmission gears is shown, but the present invention is not limited to this. In the present invention, the driving force transmission mechanism may include one, two, three, or five or more transmission gears.

[0087] Further, in the above embodiment, an example in which the shift device includes a plate member is shown, but the present invention is not limited to this. In the present invention, the shift device may not include a plate member.

[0088] In addition, in the above-described embodiment, an example in which the plate member has both a function of preventing the transmission gear from coming off the central axis and a function of maintaining the distance between the two central axes has been shown. However, the present invention is not limited to this. In the present invention, the plate member may have only a function of maintaining the distance between the two central axes of the transmission gear. In this case, it is necessary to provide a member for preventing the transmission gear from coming off the central axis separately from the plate member.

[0089] In addition, in the above-described embodiment, an example in which the plate member is fixed to the central axis by press-fitting has been shown. However, the present invention is not limited to this. In the present invention, the plate member may be fixed to the central axis by joining or the like.

[0090] In addition, in the above-described embodiment, an example in which the central axis is fixed to the middle cover by press-fitting has been shown. However, the present invention is not limited to this. In the present invention, the central axis may be fixed to the middle cover by joining or the like.

[0091] In addition, in the above-described embodiment, an example in which the middle cover is formed of aluminum has been shown. However, the present invention is not limited to this. In the present invention, the middle cover may be formed of other metal materials such as steel or resin materials.

[0092] In addition, in the above-described embodiment, an example in which the plate member is formed of a metal material has been shown. However, the present invention is not limited to this. In the present invention, the plate member may be formed of a resin material.

[0093] In addition, in the above-described embodiment, an example in which the shift device includes a shift switching member has been shown. However, the present invention is not limited to this. In the present invention, the shift device may not include a shift switching member.

[0094] In addition, in the above-described embodiment, an example in which one of the two holes of the plate member is formed as a circular press-fitting hole and the other is formed as a long hole has been shown. However, the present invention is not limited to this. In the present invention, both of the two holes of the plate member may be formed as circular press-fitting holes.

[0095] In addition, in the above-described embodiment, an example in which the long hole portion of the plate member extends in the long direction of the plate member has been shown, but the present invention is not limited to this. In the present invention, the direction in which the long hole portion of the plate member extends may be the short direction of the plate member.

[0096] In addition, in the above-described embodiment, an example in which the first central axis is inserted into the press-fitting hole portion of the plate member and the second central axis is inserted into the long hole portion of the plate member has been shown, but the present invention is not limited to this. In the present invention, the second central axis may be inserted into the press-fitting hole portion of the plate member and the first central axis may be inserted into the long hole portion of the plate member.

Explanation of Reference Numerals

[0097] 1 Actuator, 3 Driving force transmission mechanism, 4b Output shaft, 5 External housing, 6 Middle lid, 7 Plate member (anti-drop member), 7a Hole portion, 10 Motor, 10e Motor gear, 11 Control board, 20 Shift switching member, 30 Transmission gear, 31 Central axis, 31a First central axis, 31b Second central axis, 50 Housing body, 51 Cover member, 70 Press-fitting hole portion, 100 Shift device, 310 One end (of the central axis), 311 The other end (of the central axis)

Claims

1. An actuator for driving a shift switching member is provided, The actuator includes: A motor provided with a motor gear; A driving force transmission mechanism having a plurality of transmission gears for transmitting the driving force of the motor gear to an output shaft that outputs the driving force to the outside of the actuator, and a central axis of the transmission gear; An external housing for housing the motor and the driving force transmission mechanism; A middle cover housed inside the external housing and to which the motor and the driving force transmission mechanism are attached; One end of the central axis is fixed to the middle cover; The driving force transmission mechanism is a shift device that is separated from the external housing.

2. The central axis has a first central axis and a second central axis arranged parallel to each other, The driving force transmission mechanism includes a retaining member that connects the other ends of the first central axis and the second central axis to regulate the movement of the transmission gear with respect to the first central axis and the second central axis so that the transmission gear does not come off from the first central axis and the second central axis. The shift device according to Claim 1.

3. The retaining member is a plate member having two hole portions into which the other end of the first central axis and the other end of the second central axis are inserted, The two hole portions include press-fitting hole portions into which at least one of the other end of the first central axis and the other end of the second central axis is press-fitted. The shift device according to Claim 2.

4. The actuator includes a control board for controlling the motor, The control board is attached to the middle cover, The middle cover has the driving force transmission mechanism attached from one side in the axial direction of the central axis, and the control board and the motor are attached from the other side in the axial direction. The external housing includes: A housing body that covers the middle cover from one side in the axial direction in a state of being separated from the driving force transmission mechanism; A lid member that covers the middle cover from the other side in the axial direction in a state of being separated from the control board and the motor. The shift device according to Claim 1.

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