Speed reduction mechanism and electric actuator

Abstract

The utility model provides a speed reduction mechanism and an electric actuator, which can be miniaturized. The speed reduction mechanism includes: a drive-side bevel gear fixed to a motor drive shaft rotatably driven about a first axis extending in a first direction; a first rotating shaft rotatable about a second axis extending in a second direction; a driven-side bevel gear fixed to the first rotating shaft and engaged with the driving-side bevel gear; a first spur gear provided on one side of the first rotation shaft in the second direction with respect to the driven-side bevel gear; a second rotating shaft that is rotatable about a third axis that extends in the second direction and is parallel to the second axis; a second spur gear fixed to the second rotating shaft and engaged with the first spur gear; a third spur gear provided on the second rotation shaft on the other side in the second direction with respect to the second spur gear; an output shaft that is rotatable about a fourth axis that extends in the second direction and is parallel to the second axis and the third axis; the fourth spur gear is fixed to the output shaft and meshed with the third spur gear.

Description

TECHNICAL FIELD

[0001] The utility model relates to a reduction mechanism, electric actuator. BACKGROUND

[0002] A reduction mechanism that reduces and transmits the rotation of a motor shaft of a motor to a drive shaft is known (for example, Patent Literature 1). Such a reduction mechanism is provided with a drive-side gear and a driven-side gear that meshes with the drive-side gear and has a larger number of teeth than the drive-side gear. In Patent Literature 1, a structure in which the drive-side gear and the driven-side gear are provided in multiple layers is disclosed.

[0003] PRIOR ART DOCUMENTS

[0004] PATENT LITERATURE

[0005] Patent Literature 1: Japanese Patent Application Publication No. 2016-210312 SUMMARY

[0006] In the above-described reduction mechanism, in the case where the reduction mechanism is provided with multiple layers of reduction layers composed of a combination of the drive-side gear and the driven-side gear, there is a problem that the reduction mechanism is large in size.

[0007] One object of the utility model is to provide a reduction mechanism and an electric actuator that can be reduced in size.

[0008] One mode of the reduction mechanism of the utility model is provided with: a drive-side bevel gear fixed to a motor drive shaft that is driven to rotate around a first axis extending in a first direction; a first rotation shaft provided so as to be rotatable around a second axis extending in a second direction intersecting the first direction; a driven-side bevel gear fixed to the first rotation shaft and meshing with the drive-side bevel gear; a first spur gear provided on the first rotation shaft on the side of the second direction from the driven-side bevel gear; a second rotation shaft provided so as to be rotatable around a third axis extending in the second direction and parallel to the second axis; a second spur gear fixed to the second rotation shaft and meshing with the first spur gear and having a larger number of teeth than the first spur gear; a third spur gear provided on the second rotation shaft on the other side of the second direction from the second spur gear; an output shaft provided so as to be rotatable around a fourth axis extending in the second direction and parallel to the second axis and the third axis; and a fourth spur gear fixed to the output shaft and meshing with the third spur gear and having a larger number of teeth than the third spur gear.

[0009] In one mode of the speed reduction mechanism of the present application, the driven-side bevel gear and the first spur gear are formed in a gear member, and the gear member has a cylindrical spacer portion extending in the second direction between the driven-side bevel gear and the first spur gear.

[0010] In one mode of the speed reduction mechanism of the present application, the driven-side bevel gear and the first spur gear are formed in a gear member, and the gear member has a cylindrical spacer portion extending in the second direction between the driven-side bevel gear and the first spur gear.

[0011] In one mode of the speed reduction mechanism of the present application, the fourth spur gear is fixed to a first end portion on one side of the output shaft in the second direction, and the output shaft extends from the first end portion to the other side of the second direction.

[0012] In one mode of the speed reduction mechanism of the present application, the driven-side bevel gear and the first spur gear are formed in a gear member, and the gear member has a cylindrical spacer portion extending in the second direction between the driven-side bevel gear and the first spur gear.

[0013] In one mode of the speed reduction mechanism of the present application, at least a portion of the second spur gear and the fourth spur gear overlap each other as viewed in the second direction.

[0014] In one mode of the speed reduction mechanism of the present application, at least a portion of the driven-side bevel gear and the second spur gear overlap each other as viewed in the second direction.

[0015] In one mode of the speed reduction mechanism of the present application, the distance between the driven-side bevel gear and the fourth axis in the first direction is smaller than the distance between the third axis and the driven-side bevel gear in the first direction.

[0016] One mode of the electric actuator of the present application includes the speed reduction mechanism described above, a housing that accommodates the speed reduction mechanism, and the motor.

[0017] According to one aspect of the present application, a speed reduction mechanism and an electric actuator that can be downsized can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a perspective view of an electric actuator of one embodiment.

[0019] Figure 2 is a perspective view showing a state in which a housing cover and a speed reducer cover are removed in the electric actuator of one embodiment.

[0020] Figure 3 is a side view of the electric actuator of one embodiment.

[0021] Figure 4 is a view of a motor and a reduction mechanism of an electric actuator according to an embodiment, as viewed from a third direction.

[0022] Figure 5 is a view of a motor and a reduction mechanism of an electric actuator according to an embodiment, as viewed from above.

[0023] Figure 6 is a perspective view of a motor and a reduction mechanism of an electric actuator according to an embodiment.

[0024] Figure 7 is a perspective view of a reduction mechanism according to an embodiment, as viewed from a direction different from Figure 6 .

[0025] Figure 8 is a view of a reduction mechanism according to an embodiment, as viewed from a direction different from Figure 4 . DETAILED DESCRIPTION

[0026] Figure 1 is a perspective view of an electric actuator 90 according to the present embodiment. Figure 2 is a perspective view showing a state in which a housing cover and a reduction cover 15 are removed from the electric actuator 90 according to the present embodiment.

[0027] In each drawing, the Z-axis direction is a vertical direction with a positive side (+Z side) as an upper side and a negative side (-Z side) as a lower side. In the present embodiment, the upper side corresponds to the other side in the axial direction, and the lower side corresponds to the one side in the axial direction. Note that the upper side and the lower side are merely names for explaining the relative positional relationship of each part, and the actual arrangement relationship and the like can be an arrangement relationship and the like other than those indicated by the names.

[0028] In each drawing, the first direction D1 is a direction orthogonal to the Z-axis direction. In each drawing, the second direction D2 is parallel to the Z-axis direction. The third direction D3 is a direction orthogonal to both the first direction D1 and the second direction D2. In the following description, the side toward which the arrow of the second direction D2 points (+D2 side) is referred to as the "one side of the second direction D2", and the side opposite to the side toward which the arrow of the second direction D2 points (-D2 side) is referred to as the "other side of the second direction D2".

[0029] Figure 1 , Figure 2 The electric actuator 90 according to the present embodiment shown in FIG. 1 is mounted to a vehicle or the like, for example. As shown in FIG. 2, the electric actuator 90 includes a housing 10, a motor 20, a reduction mechanism 30 (see FIG. 3), a substrate portion (not shown), and an output shaft 50 (see FIG. 4). Figure 1 , Figure 2 As shown in FIG. 2, the electric actuator 90 includes the housing 10, the motor 20, the reduction mechanism 30 (see FIG. 3), the substrate portion (not shown), and the output shaft 50 (see FIG. 4). Figure 2 Figure 5 As shown in FIG. 2, the electric actuator 90 includes the housing 10, the motor 20, the reduction mechanism 30 (see FIG. 3), the substrate portion (not shown), and the output shaft 50 (see FIG. 4).​

[0030] The housing 10 internally houses the motor 20, the reduction mechanism 30, and a substrate portion (not shown). The housing 10 has a housing main body 11, a reducer cover 15 (refer to Figure 1 ), and a housing cover (not shown).

[0031] Figure 3 is a side view of the electric actuator 90 of the present embodiment.

[0032] The housing main body 11 has an opening portion 11b that is open at an upper side. As shown in Figure 2 , Figure 3 , the housing main body 11 has a bottom wall portion 13 and a peripheral wall portion 14. The bottom wall portion 13 of the present embodiment, for example, has an L shape as viewed from the upper side. The bottom wall portion 13 has a plate-shaped portion 131, a reducer housing portion 132, and a motor housing portion 133. The plate-shaped portion 131 is a plate shape that extends in a direction orthogonal to the up-down direction.

[0033] The reducer housing portion 132 is recessed downward from the plate-shaped portion 131. As shown in Figure 3 , the reducer housing portion 132 has a wall portion 132w and a closing portion 132c. The wall portion 132w is a cylinder shape that extends downward from the plate-shaped portion 131. The wall portion 132w has a shape that can house the reduction mechanism 30 described later as viewed from the second direction D2. The closing portion 132c closes the lower end of the wall portion 132w from below. Such a reducer housing portion 132 is open at the upper side. The reducer housing portion 132 houses the reduction mechanism 30.

[0034] The motor housing portion 133 is recessed downward from the plate-shaped portion 131. The motor housing portion 133 has a curved wall portion 133w and an end wall portion 133c. The curved wall portion 133w is a semicircular arc shape as viewed from the first direction D1 and extends along the first direction D1. The end wall portion 133c closes both end portions of the curved wall portion 133w in the first direction D1. Such a motor housing portion 133 is open at the upper side. The motor housing portion 133 houses the motor 20.

[0035] As shown in Figure 2 , the width dimension in the third direction D3 of the motor housing portion 133 is smaller than that of the reducer housing portion 132 as viewed from the upper side. The motor housing portion 133 is biased to the other side of the third direction D3 of the reducer housing portion 132. The motor housing portion 133 extends from the one side of the third direction D3 of the reducer housing portion 132 toward the one side of the first direction D1.

[0036] The peripheral wall portion 14 stands up from the outer peripheral edge portion of the bottom wall portion 13 toward the upper side. The peripheral wall portion 14 surrounds the space at the upper side of the bottom wall portion 13 from the outside.

[0037] As shown in Figure 1As shown, the decelerator cover 15 is disposed on the inner side of the peripheral wall portion 14 as viewed from the upper side. The decelerator cover 15 covers the deceleration mechanism 30 housed in the decelerator housing portion 132 from the upper side. The decelerator cover 15 is fixed to the plate-shaped portion 131 around the decelerator housing portion 132 by screws or the like.

[0038] The housing cover (not shown) closes the opening portion 1 lb of the housing main body 11 from the upper side.

[0039] The housing main body 11 has a connector portion 17 and bracket portions 18. The connector portion 17 protrudes from the peripheral wall portion 14 to one side in the first direction Dl. The connector portion 17 can detachably mount a cable (not shown) that supplies electric power to the motor 20 from the outside. The bracket portions 18 are provided around the peripheral wall portion 14. The bracket portions 18 are provided, for example, at three positions around the peripheral wall portion 14. Each bracket portion 18 protrudes from the peripheral wall portion 14 to the outside. Each bracket portion 18 has a through-hole 18h that penetrates the bracket portion 18 in the up-down direction. By inserting a bolt (not shown) through the through-hole 18h of each bracket portion 18 and fastening it to a vehicle body or the like, the housing 10 can be fixed to the vehicle body or the like.

[0040] Figure 4 is a view of the motor 20 and the deceleration mechanism 30 of the electric actuator 90 of the present embodiment as viewed from the third direction. Figure 5 is a view of the motor 20 and the deceleration mechanism 30 of the electric actuator 90 of the present embodiment as viewed from above. Figure 6 is a perspective view of the motor 20 and the deceleration mechanism 30 of the electric actuator 90 of the present embodiment.

[0041] The motor 20 is housed in a motor housing portion 133. As shown in Figure 2 , Figure 4 to Figure 6 The motor 20 has a motor case 21, a rotor (not shown), a motor drive shaft 23, and a stator (not shown), as shown.

[0042] The rotor is rotatable about a first axis Jl extending in the first direction Dl. A magnet (not shown) is fixed to the rotor. The magnet is disposed at a plurality of positions spaced apart in the circumferential direction. The motor drive shaft 23 is fixed to the rotor. The motor drive shaft 23 protrudes from the motor case 21 to the other side in the first direction Dl. The motor drive shaft 23 has a cylindrical shape extending about the first axis Jl. The motor drive shaft 23 rotates integrally with the rotor about the first axis Jl.

[0043] The stator is arranged radially outward of the rotor with the first axis J1 as a center. The stator opposes the rotor with a gap in the radial direction. The stator has a coil portion (not shown) that obtains electric power from a substrate portion (not shown). The motor 20 rotates and drives the rotor and the motor drive shaft 23 with the first axis J1 as a center by a magnetic field generated by the coil portion of the stator by electric power supplied from the substrate portion (not shown).

[0044] Figure 7 is a perspective view of the speed reduction mechanism 30 of the present embodiment, as viewed from a different direction from Figure 6 Figure 8 is a view of the speed reduction mechanism 30 of the present embodiment, as viewed from a different direction from Figure 4

[0045] The speed reduction mechanism 30 transmits the rotation of the motor drive shaft 23 of the motor 20 to the output shaft 50. The speed reduction mechanism 30 reduces and transmits the rotation of the motor drive shaft 23 to the output shaft 50 at a predetermined speed reduction ratio. As Figure 4 to Figure 8 indicated, the speed reduction mechanism 30 includes a drive-side bevel gear 31, a first rotation shaft 32, a driven-side bevel gear 33, a first spur gear 34, a second rotation shaft 35, a second spur gear 36, a third spur gear 37, and a fourth spur gear 38.

[0046] The drive-side bevel gear 31 transmits the rotation of the motor drive shaft 23 to the driven-side bevel gear 33. The drive-side bevel gear 31 is fixed to the front end portion on the other side of the first direction D1 of the motor drive shaft 23. The drive-side bevel gear 31 is a conical shape in which the outer diameter gradually decreases from the one side of the first direction D1 toward the other side. The drive-side bevel gear 31 has a plurality of bevel gear teeth 31g in the circumferential direction with the first axis J1 as a center on the other side of the first direction D1. The drive-side bevel gear 31 rotates with the first axis J1 as a center integrally with the motor drive shaft 23 by the drive of the motor 20.

[0047] The first rotation shaft 32, the second rotation shaft 35, and the output shaft 50 are each a cylindrical shape extending in a second direction D2 intersecting the first direction D1. The first rotation shaft 32 is supported to the housing main body 11 via a bearing (not shown). The first rotation shaft 32 rotates freely with the second axis J2 extending in the second direction D2 as a center. The first rotation shaft 32 is arranged to depart from the motor drive shaft 23 toward the other side of the first direction D1. The first rotation shaft 32 is arranged such that the first axis J1 and the second axis J2 overlap when viewed from the second direction D2.

[0048] ​​The driven-side bevel gear 33 is engaged with the driving-side bevel gear 31. The driven-side bevel gear 33 is disposed on the other side of the second direction D2 with respect to the driving-side bevel gear 31. The driven-side bevel gear 33 is fixed to the end portion of the first rotary shaft 32 on the other side of the second direction D2. The driven-side bevel gear 33 is rotatable about the second axis J2 integrally with the first rotary shaft 32. The driven-side bevel gear 33 is a disc shape extending along a plane intersecting the second direction D2. The driven-side bevel gear 33 is a circular truncated cone shape in which the outer diameter is gradually reduced from the other side toward the one side of the second direction D2. The driven-side bevel gear 33 has a plurality of bevel gear teeth 33g on the plane toward the one side of the second direction D2. The plurality of bevel gear teeth 33g are provided at the outer peripheral portion of the driven-side bevel gear 33. The bevel gear teeth 33g of the driven-side bevel gear 33 are engaged with the bevel gear teeth 31g of the driving-side bevel gear 31. The number of teeth of the bevel gear teeth 33g of the driven-side bevel gear 33 is more than the number of teeth of the bevel gear teeth 31g of the driving-side bevel gear 31.

[0049] The first spur gear 34 transmits the rotation of the first rotary shaft 32 to the second spur gear 36. The first spur gear 34 is fixed to the end portion of the first rotary shaft 32 on the one side of the second direction D2. The first spur gear 34 is a disc plate shape centered on the second axis J2. The outer diameter of the first spur gear 34 is smaller than the outer diameter of the driven-side bevel gear 33. The first spur gear 34 has a plurality of gear teeth 34g on the plane toward the radially outer side centered on the second axis J2. The number of teeth of the gear teeth 34g of the first spur gear 34 is smaller than the number of teeth of the bevel gear teeth 33g of the driven-side bevel gear 33.

[0050] A spacer 391 is provided between the driven-side bevel gear 33 and the first spur gear 34. The spacer 391 is a cylindrical shape extending in the second direction D2. By this spacer 391, the first spur gear 34 is disposed on the one side of the second direction D2 with respect to the driven-side bevel gear 33 at a prescribed interval. The driven-side bevel gear 33, the spacer 391, and the first spur gear 34 are provided as an integrated gear member 39.

[0051] The second rotary shaft 35 is supported to the housing main body 11 via a bearing not shown. The second rotary shaft 35 is rotatable about a third axis J3 extending in the second direction D2. As shown in FIG. 1, the second rotary shaft 35 is disposed on the other side of the first direction D1 and on the one side of the third direction D3 with respect to the first rotary shaft 32. Figure 5

[0052] As shown in FIG. 1, the second rotary shaft 35 is disposed on the other side of the first direction D1 and on the one side of the third direction D3 with respect to the first rotary shaft 32. Figure 4 to Figure 8 ​As shown, the second spur gear 36 is fixed to one end of the second rotating shaft 35 in the second direction D2. The second spur gear 36 is disc-shaped and centered on the third axis J3. A portion of the second spur gear 36 overlaps with the driven bevel gear 33 when viewed from the second direction D2. The second spur gear 36 rotates integrally with the second rotating shaft 35 around the third axis J3. The second spur gear 36 is disposed radially outside the first spur gear 34. The second spur gear 36 meshes with the first spur gear 34. The outer diameter of the second spur gear 36 is larger than the outer diameter of the first spur gear 34. The second spur gear 36 has a plurality of gear teeth 36g on a surface centered on the third axis J3 and facing radially outward. The number of teeth 36g of the second spur gear 36 is greater than the number of teeth 34g of the first spur gear 34.

[0053] Figure 4 , Figure 8 The third spur gear 37, as shown, transmits the rotation of the second rotating shaft 35 to the fourth spur gear 38. The third spur gear 37 is positioned on the opposite side of the second spur gear 36 in the second direction D2. The third spur gear 37 is fixed to the second rotating shaft 35. The third spur gear 37 rotates integrally with the second rotating shaft 35 around the third axis J3. The third spur gear 37 is positioned in the second direction D2 between the driven bevel gear 33 and the first spur gear 34 and the second spur gear 36. The third spur gear 37 is disc-shaped, centered on the third axis J3. The outer diameter of the third spur gear 37 is smaller than the outer diameter of the second spur gear 36. The third spur gear 37 has a plurality of gear teeth 37g on a surface oriented radially outward around the third axis J3. The number of teeth 37g of the third spur gear 37 is less than the number of teeth 36g of the second spur gear 36.

[0054] like Figure 4 to Figure 8 As shown, the output shaft 50 outputs the driving force of the electric actuator 90. The output shaft 50 is supported on the housing body 11 via a bearing (not shown). Figure 5 As shown, the output shaft 50 is positioned relative to the first rotation shaft 32 on the opposite side of the first direction D1 and on the side of the third direction D3. The output shaft 50 is also positioned relative to the second rotation shaft 35 on the side of the first direction D1 and on the side of the third direction D3. Figure 4 to Figure 8 As shown, the output shaft 50 is rotatable about a fourth axis J4 that extends along the second direction D2 and is parallel to the second axis J2 and the third axis J3. The output shaft 50 has a generally cylindrical shape extending along the second direction D2 about the fourth axis J4. A first end 50s on one side of the output shaft 50 in the second direction D2 is positioned in the second direction D2, overlapping with the first spur gear 34 and the second spur gear 36. Figure 3 As shown, the second end 50t on the other side of the second direction D2 of the output shaft 50 protrudes outward from the housing 10 through a through hole (not shown) formed in the housing 10.

[0055] As shown in Figure 4 to Figure 8 , the fourth spur gear 38 is fixed to an end portion on one side in the second direction D2 of the output shaft 50. The fourth spur gear 38 is a sector plate shape expanding with the fourth axis J4 as a center when viewed from the second direction D2. The fourth spur gear 38 rotates (oscillates) with the fourth axis J4 as a center integrally with the output shaft 50. As shown in Figure 5 , Figure 7 , the fourth spur gear 38 has a circular-arc-shaped portion 38s in a circular-arc shape when viewed from the second direction D2 in an outer peripheral portion with the fourth axis J4 as a center. A portion (circular-arc-shaped portion 38s) of the fourth spur gear 38 overlaps the driven-side bevel gear 33 and the second spur gear 36 when viewed from the second direction D2. The fourth spur gear 38 is disposed radially outward of the third spur gear 37. The fourth spur gear 38 is engaged with the third spur gear 37. The diameter dimension of the circular-arc-shaped portion 38s of the fourth spur gear 38 with the fourth axis J4 as a center is larger than the outer diameter of the third spur gear 37. The circular-arc-shaped portion 38s of the fourth spur gear 38 has a plurality of gear teeth 38g on a surface toward the radially outer side with the fourth axis J4 as a center. The number of gear teeth 38g of the fourth spur gear 38 is larger than the number of gear teeth 37g of the third spur gear 37.

[0056] In such a reduction mechanism 30, as shown in Figure 4 , Figure 8 , the driven-side bevel gear 33, the first spur gear 34, the second spur gear 36, the third spur gear 37, and the fourth spur gear 38 are disposed on the first layer G1, the second layer G2, and the third layer G3 arranged from one side to the other side in the second direction D2. The first layer G1 is located on the most one side in the second direction D2. The second layer G2 is located on the other side in the second direction D2 with respect to the first layer G1. The third layer G3 is located on the other side in the second direction D2 with respect to the first layer G1 and the second layer G2. That is, the first layer G1, the second layer G2, and the third layer G3 are arranged from one side to the other side in the second direction D2 in this order.

[0057] The first spur gear 34 and the second spur gear 36 of the present embodiment are disposed on the first layer G1. The third spur gear 37 and the fourth spur gear 38 are disposed on the second layer G2. The driven-side bevel gear 33 is disposed on the third layer G3.

[0058] When the motor 20 rotates the motor drive shaft 23 about the first axis line J1 as a center by the electric motor actuator 90, the rotation of the motor drive shaft 23 is transmitted to the output shaft 50 via the speed reduction mechanism 30. In detail, the rotation of the motor drive shaft 23 is transmitted to the output shaft 50 via the drive-side bevel gear 31, the driven-side bevel gear 33, the first rotation shaft 32, the first spur gear 34, the second spur gear 36, the second rotation shaft 35, the third spur gear 37, and the fourth spur gear 38. The rotation of the motor drive shaft 23 is reduced at a predetermined reduction ratio via the drive-side bevel gear 31, the driven-side bevel gear 33, the first spur gear 34, the second spur gear 36, the third spur gear 37, and the fourth spur gear 38.

[0059] According to the present embodiment, the speed reduction mechanism 30 includes: the drive-side bevel gear 31 fixed to the motor drive shaft 23 that is driven to rotate about the first axis line J1 extending in the first direction D1; the first rotation shaft 32 provided so as to be rotatable about the second axis line J2 extending in the second direction D2 intersecting the first direction D1; the driven-side bevel gear 33 fixed to the first rotation shaft 32 and engaged with the drive-side bevel gear 31; the first spur gear 34 provided on the first rotation shaft 32 on the side of the second direction D2 with respect to the driven-side bevel gear 33; the second rotation shaft 35 provided so as to be rotatable about the third axis line J3 extending in the second direction D2 and parallel to the second axis line J2; the second spur gear 36 fixed to the second rotation shaft 35 and engaged with the first spur gear 34, the number of teeth of which is larger than that of the first spur gear 34; the third spur gear 37 provided on the second rotation shaft 35 on the other side of the second direction D2 with respect to the second spur gear 36; the output shaft 50 provided so as to be rotatable about the fourth axis line extending in the second direction D2 and parallel to the second axis line J2 and the third axis line J3; and the fourth spur gear 38 fixed to the output shaft 50 and engaged with the third spur gear 37, the number of teeth of which is larger than that of the third spur gear 37. Thus, the speed reduction mechanism 30 can be downsized in the second direction D2.

[0060] According to the present embodiment, the driven-side bevel gear 33 and the first spur gear 34 are provided apart from each other in the second direction D2, and the third spur gear 37 and the fourth spur gear 38 are disposed between the driven-side bevel gear 33 and the first spur gear 34 in the second direction D2. Thus, the speed reduction mechanism 30 can be downsized in the second direction D2.

[0061] In the present embodiment, the gear member 39 in which the driven-side bevel gear 33 and the first spur gear 34 are formed in one body. The gear member 39 has a cylindrical space portion 391 extending in the second direction D2 between the driven-side bevel gear 33 and the first spur gear 34. Thus, the third spur gear 37 and the fourth spur gear 38 can be arranged in the second direction D2 between the driven-side bevel gear 33 and the first spur gear 34. According to the present embodiment, the driven-side bevel gear 33 and the first spur gear 34 can be arranged separately in the second direction D2. Thus, the first rotary shaft 32 is less likely to be inclined during driving, and the rotation of the first rotary shaft 32 about the second axis J2 can be stabilized. As a result, the driving efficiency of the speed reduction mechanism 30 can be improved.

[0062] The fourth spur gear 38 of the present embodiment is fixed to the first end portion 50s on one side in the second direction D2 of the output shaft 50. In addition, the output shaft 50 extends from the first end portion 50s to the other side in the second direction D2. According to the present embodiment, the output shaft 50 can be shortened in the second direction D2 as compared with a case where the fourth spur gear 38 is arranged in the middle of the length direction of the output shaft 50. As a result, the speed reduction mechanism 30 can be downsized in the second direction D2.

[0063] The drive-side bevel gear 31 of the present embodiment is arranged on the one side in the second direction D2 with respect to the driven-side bevel gear 33. According to the present embodiment, the drive-side bevel gear 31 is arranged between the driven-side bevel gear 33 and the first spur gear 34. That is, the drive-side bevel gear 31 can be arranged so as to overlap other gears in the second direction D2. As a result, the speed reduction mechanism 30 can be downsized in the second direction D2.

[0064] In the present embodiment, at least a part of the second spur gear 36 and the fourth spur gear 38 overlap each other as viewed in the second direction D2. According to the present embodiment, the speed reduction mechanism 30 can be downsized in the first direction D1 and the third direction D3.

[0065] According to the present embodiment, at least a part of the driven-side bevel gear 33 and the second spur gear 36 overlap each other as viewed in the second direction D2. Thus, the speed reduction mechanism 30 can be downsized in the first direction D1 and the third direction D3.

[0066] In the present embodiment, the distance dimension H1 of the drive-side bevel gear 31 in the first direction D1 from the fourth axis J4 is smaller than the distance dimension H2 of the drive-side bevel gear 31 in the first direction D1 from the third axis J3. According to the present embodiment, the axes can be arranged densely in the first direction D1 from each other, and the speed reduction mechanism 30 can be downsized in the first direction D1.

[0067] According to the present embodiment, the electric actuator 90 is provided with the speed reduction mechanism 30, the housing 10 that houses the speed reduction mechanism 30, and the motor 20. Thus, it is possible to provide an electric actuator 90 that is provided with a speed reduction mechanism 30 that can be downsized.

[0068] The above describes one embodiment and modifications thereof of the present application, but the structures and combinations thereof in the embodiment and modifications are one example, and in a range not departing from the gist of the present application, addition, omission, substitution, and other changes of the structures can be made. In addition, the present application is not limited by the embodiment.

[0069] For example, in the above embodiment, the third spur gear 37 and the fourth spur gear 38 are disposed on the second layer G2, and the driven-side bevel gear 33 is disposed on the third layer G3, but this is not limiting. The third spur gear 37 and the fourth spur gear 38 can be disposed on the third layer G3, and the driven-side bevel gear 33 can be disposed on the second layer G2.

[0070] In addition, in the above embodiment, the drive-side bevel gear 31 is disposed on one side in the second direction D2 with respect to the driven-side bevel gear 33, but this is not limiting. The drive-side bevel gear 31 can be disposed on the other side in the second direction D2 with respect to the driven-side bevel gear 33.

[0071] In addition, the use of the speed reduction mechanism 30 and the electric actuator 90 of the above embodiment is not particularly limited. The speed reduction mechanism 30 and the electric actuator 90 of the above embodiment can be installed in a device other than a vehicle.

[0072] Note that the present technology can employ the following configurations.

[0073] (1) A speed reduction mechanism including: a drive-side bevel gear fixed to a motor drive shaft that is driven to rotate about a first axis extending in a first direction; a first rotary shaft provided so as to be rotatable about a second axis extending in a second direction that crosses the first direction; a driven-side bevel gear fixed to the first rotary shaft and engaged with the drive-side bevel gear; a first spur gear provided on the first rotary shaft on one side in the second direction with respect to the driven-side bevel gear; a second rotary shaft provided so as to be rotatable about a third axis extending in the second direction and parallel to the second axis; a second spur gear fixed to the second rotary shaft and engaged with the first spur gear, the second spur gear having a larger number of teeth than the first spur gear; a third spur gear provided on the second rotary shaft on the other side in the second direction with respect to the second spur gear; an output shaft provided so as to be rotatable about a fourth axis extending in the second direction and parallel to the second axis and the third axis; and a fourth spur gear fixed to the output shaft and engaged with the third spur gear, the fourth spur gear having a larger number of teeth than the third spur gear.

[0074] (2) The speed reduction mechanism according to (1), wherein the driven-side bevel gear and the first spur gear are provided at intervals in the second direction, and the third spur gear and the fourth spur gear are disposed between the driven-side bevel gear and the first spur gear in the second direction.

[0075] (3) The speed reduction mechanism according to (2), wherein the driven-side bevel gear and the first spur gear are formed in a gear member having a cylindrical interval portion extending in the second direction between the driven-side bevel gear and the first spur gear.

[0076] (4) The speed reduction mechanism according to (2) or (3), wherein the fourth spur gear is fixed to a first end portion of the output shaft on one side in the second direction, and the output shaft extends from the first end portion toward the other side in the second direction.

[0077] (5) The speed reduction mechanism according to any one of (1) to (4), wherein the drive-side bevel gear is provided on one side in the second direction with respect to the driven-side bevel gear.

[0078] (6) The speed reduction mechanism according to any one of (1) to (5), wherein at least a portion of the second spur gear and the fourth spur gear overlap each other as viewed in the second direction.

[0079] (7) The speed reduction mechanism according to any one of (1) to (6), wherein at least a portion of the driven-side bevel gear and the second spur gear overlap each other as viewed in the second direction.

[0080] (8) The speed reduction mechanism according to any one of (1) to (7), wherein a distance dimension of the drive-side bevel gear in the first direction from the third axis is smaller than a distance dimension of the drive-side bevel gear in the first direction from the fourth axis.

[0081] (9) An electric actuator including: the speed reduction mechanism according to any one of (1) to (8); a housing that houses the speed reduction mechanism; and a motor having the motor drive shaft.

[0082] Explanation of symbols

[0083] 10… housing, 20… motor, 23… motor drive shaft, 30… speed reduction mechanism, 31… drive side bevel gear, 32… first rotation shaft, 33… driven side bevel gear, 34… first spur gear, 35… second rotation shaft, 36… second spur gear, 37… third spur gear, 38… fourth spur gear, 39… gear member, 50… output shaft, 50s… first end portion, 90… electric actuator, 391… interval portion, D1… first direction, D2… second direction, H1, H2… distance dimension, J1… first axis, J2… second axis, J3… third axis, J4… fourth axis.

Claims

1. A speed reduction mechanism, characterized in that, have: A drive-side bevel gear, which is fixed to a motor drive shaft that is driven to rotate about a first axis extending in a first direction; A first rotation axis is configured to rotate freely about a second axis extending in a second direction intersecting the first direction; The driven bevel gear is fixed to the first rotating shaft and meshes with the driving bevel gear; A first spur gear is disposed on one side of the first rotating shaft relative to the driven bevel gear in the second direction; A second rotation axis is configured to rotate freely about a third axis that extends along the second direction and is parallel to the second axis. The second spur gear is fixed to the second rotating shaft and meshes with the first spur gear, and has more teeth than the first spur gear; A third spur gear is disposed on the opposite side of the second spur gear on the second rotational shaft in the second direction; An output shaft configured to rotate freely about a fourth axis extending along the second direction and parallel to the second and third axes; as well as A fourth spur gear is fixed to the output shaft, meshes with the third spur gear, and has more teeth than the third spur gear.

2. The speed reduction mechanism according to claim 1, characterized in that, The driven bevel gear and the first spur gear are spaced apart in the second direction. The third spur gear and the fourth spur gear are disposed in the second direction between the driven side bevel gear and the first spur gear.

3. The speed reduction mechanism according to claim 2, characterized in that, The driven bevel gear and the first spur gear are formed as a single gear component. The gear component has a cylindrical spacer extending in the second direction between the driven bevel gear and the first spur gear.

4. The speed reduction mechanism according to claim 2 or 3, characterized in that, The fourth spur gear is fixed to the first end of one side of the output shaft in the second direction. The output shaft extends from the first end to the other side in the second direction.

5. The speed reduction mechanism according to claim 1 or 2, characterized in that, The driving bevel gear is positioned on one side of the driven bevel gear in the second direction.

6. The speed reduction mechanism according to claim 1 or 2, characterized in that, Viewed from the second direction, at least a portion of the second spur gear and the fourth spur gear overlap each other.

7. The speed reduction mechanism according to claim 1 or 2, characterized in that, Viewed from the second direction, at least a portion of the driven bevel gear and the second spur gear overlap each other.

8. The speed reduction mechanism according to claim 1 or 2, characterized in that, The distance between the drive-side bevel gear in the first direction and the fourth axis is smaller than the distance between the third axis in the first direction and the drive-side bevel gear.

9. An electric actuator, characterized in that, have: The deceleration mechanism as described in claim 1 or 2; Housing, which houses the reduction gear mechanism; and A motor having the motor drive shaft.

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