JP2019184060A - Speed reduction mechanism and motor with speed reduction mechanism - Google Patents

Abstract

To provide a speed reduction mechanism having gears engaged to each other capable of further enlarging a gear reduction ratio and provide a motor including the speed reduction mechanism.SOLUTION: A pinion gear 31 is provided with one helical engaged protrusion part 31c and a helical gear 32 is provided with several engaged recess parts 32d having an engaging protrusion 31c, each of the engaged protrusion part 31c and engaged recess part 32d being formed to have a circular arc shape in a direction orthogonal to an axial direction of the pinion gear 31. Accordingly, the pinion gear 31 and the helical gear 32 can be formed into an engaging structure of convexoconcave arc shape not showing a poor engaged state and it is possible to increase a difference in the number of teeth by increasing the number of teeth of the helical gears 32 while the number of teeth of the pinion gear 31 is being set to 1. Accordingly, it becomes possible to further increase a gear reduction ratio without enlarging a size of a speed reduction mechanism 30.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a speed reduction mechanism including a first gear and a second gear meshed with each other, and a motor with a speed reduction mechanism.

  2. Description of the Related Art Conventionally, a drive motor such as a wiper device or a power window device mounted on a vehicle such as an automobile employs a motor with a speed reduction mechanism that is small in size and capable of large output. Such a vehicle-mounted motor with a speed reduction mechanism is described in Patent Document 1, for example.

  The motor with a speed reduction mechanism described in Patent Document 1 is used as a drive source for a seat lifter device, and includes an electric motor and a housing. In the housing, the number of small teeth rotated by the rotating shaft of the electric motor is a helical gear, the number of small teeth is a driven helical gear meshed with the helical gear, and the driven side is a helical gear. A worm that rotates integrally with the gear and a worm wheel that meshes with the worm are rotatably accommodated.

  Thus, in the motor with a speed reduction mechanism described in Patent Document 1, a two-stage speed reduction mechanism is housed inside the housing. Specifically, the first-stage reduction mechanism is constituted by a helical gear having a small number of teeth and a helical gear on the driven side, and the second-stage reduction mechanism is constituted by a worm and a worm wheel. As a result, the motor with the speed reduction mechanism can be reduced in size and installed on the side of the seat.

JP 2017-133582 A

  However, in the technique described in Patent Document 1 described above, for example, an involute gear is used for the helical gear and the driven side helical gear with the small number of teeth constituting the first-stage reduction mechanism. Therefore, when it is necessary to further increase the reduction ratio, the following problems can occur.

  That is, in order to increase the reduction gear ratio, it is necessary to increase the difference in the number of teeth between the helical gear and the driven side helical gear. However, the number of small teeth is “2”, and the number of teeth is already small. Therefore, considering that the number of teeth of the helical gear is increased on the driven side, in this case, adjacent teeth of the helical gear are arranged close to each other on the driven side, and the meshing surface of the teeth stands substantially vertically. And become flat.

  Then, the number of small teeth causes a problem that the teeth of the helical gear and the teeth of the helical gear on the driven side interfere with each other, and consequently the meshing state is deteriorated. As described above, the involute gear has a limit in meeting the need to further increase the reduction ratio without increasing the size of the reduction mechanism.

  An object of the present invention is to provide a speed reduction mechanism and a motor with a speed reduction mechanism, each having a meshing gear capable of increasing the speed reduction ratio.

  The speed reduction mechanism of the present invention is a speed reduction mechanism provided with a first gear and a second gear, and is provided on the first gear, and has a first tooth portion extending spirally in the axial direction of the first gear; A meshing convex portion provided on the first tooth portion, formed in an arc shape in a direction orthogonal to the axial direction of the first gear, and provided with a center of curvature at a position eccentric from the rotation center of the first gear. A plurality of second tooth portions provided on the second gear, inclined with respect to the axial direction of the first gear and arranged in the circumferential direction of the second gear, and the second tooth portions adjacent to each other. A meshing recess provided between each other, formed in an arc shape in a direction orthogonal to the axial direction of the first gear, and meshed with the meshing projection.

  In another aspect of the present invention, the reduction ratio of the first gear and the second gear is such that the first distance between the center of curvature of the meshing convex portion and the rotation center of the first gear, and the meshing concave portion. It is equal to the ratio of the second distance between the center of curvature and the center of rotation of the second gear.

  In another aspect of the present invention, the first tooth portion has an apex provided on the meshing convex portion and a center of curvature of the meshing convex portion at the radially outer end of the first gear. And an escape portion that is provided at an end opposite to the apex and prevents interference with the second tooth portion.

  In another aspect of the invention, the axis of the first gear and the axis of the second gear are parallel.

  In another aspect of the present invention, there is further provided a housing that forms an outline of the speed reduction mechanism, wherein the first gear is a sun gear, the second gear is a plurality of planetary gears, and the planetary gears. An inner shaft fixed to the housing, and a carrier provided with an output shaft coaxial with the sun gear and an inner tooth meshed with the second tooth portion provided on the planetary gear. And a gear.

  In another aspect of the present invention, there is further provided a housing that forms an outline of the speed reduction mechanism, wherein the first gear is a sun gear, the second gear is a plurality of planetary gears, and the planetary gears. And a support member fixed to the housing, and an internal tooth with which the second tooth portion provided on the planetary gear meshes, and an output shaft coaxial with the sun gear is provided. And an internal gear.

  The motor with a speed reduction mechanism of the present invention is a motor with a speed reduction mechanism comprising a motor having a rotating body, a first gear rotated by the rotating body, and a second gear rotated by the first gear. A first tooth portion provided in the first gear and extending spirally in the axial direction of the first gear; and a direction provided in the first tooth portion and orthogonal to the axial direction of the first gear. Formed in a circular arc shape and having a center of curvature provided at a position eccentric from the rotation center of the first gear, and provided on the second gear and inclined with respect to the axial direction of the first gear. And a plurality of second tooth portions arranged in the circumferential direction of the second gear and an arc shape in a direction perpendicular to the axial direction of the first gear provided between the adjacent second tooth portions. And a meshing recess that meshes with the meshing projection, and a rotation of the second gear. Having an output shaft provided in the center, the.

  In another aspect of the present invention, the reduction ratio of the first gear and the second gear is such that the first distance between the center of curvature of the meshing convex portion and the rotation center of the first gear, and the meshing concave portion. It is equal to the ratio of the second distance between the center of curvature and the center of rotation of the second gear.

  In another aspect of the present invention, the first tooth portion has an apex provided on the meshing convex portion and a center of curvature of the meshing convex portion at the radially outer end of the first gear. And an escape portion that is provided at an end opposite to the apex and prevents interference with the second tooth portion.

  In another aspect of the invention, the axis of the first gear and the axis of the second gear are parallel.

  In the motor with a speed reduction mechanism of the present invention, a motor having a rotating body, a sun gear rotated by the rotating body, a plurality of planetary gears rotated by the sun gear, and an internal gear meshed with the planetary gear; A first motor provided with a speed reduction mechanism, the housing including the sun gear, the planetary gear, and the internal gear, and a first one provided in the sun gear and extending in a spiral manner in an axial direction of the sun gear. A meshing projection provided on the tooth portion and the first tooth portion, formed in an arc shape in a direction orthogonal to the axial direction of the sun gear, and provided with a center of curvature at a position eccentric from the rotation center of the sun gear. A plurality of second tooth portions provided on the planetary gear, inclined with respect to the axial direction of the sun gear and arranged in the circumferential direction of the planetary gear, and between the adjacent second tooth portions Provided in between An engagement recess that is formed in an arc shape in a direction orthogonal to the axial direction of the positive gear, meshes with the engagement protrusion, rotatably supports the planetary gear, and is provided with an output shaft that is coaxial with the sun gear. A carrier, and the internal gear includes an internal tooth with which the second tooth portion provided on the planetary gear is engaged, and is fixed to the housing.

  In the motor with a speed reduction mechanism of the present invention, a motor having a rotating body, a sun gear rotated by the rotating body, a plurality of planetary gears rotated by the sun gear, and an internal gear meshed with the planetary gear; A first motor provided with a speed reduction mechanism, the housing including the sun gear, the planetary gear, and the internal gear, and a first one provided in the sun gear and extending in a spiral manner in an axial direction of the sun gear. A meshing projection provided on the tooth portion and the first tooth portion, formed in an arc shape in a direction orthogonal to the axial direction of the sun gear, and provided with a center of curvature at a position eccentric from the rotation center of the sun gear. A plurality of second tooth portions provided on the planetary gear, inclined with respect to the axial direction of the sun gear and arranged in the circumferential direction of the planetary gear, and between the adjacent second tooth portions Provided in between A meshing recess formed in an arc shape in a direction perpendicular to the axial direction of the positive gear and meshing with the meshing projection, and a support member that rotatably supports the planetary gear and is fixed to the housing. The internal gear includes an internal tooth with which the second tooth portion provided on the planetary gear is engaged, and has an output shaft coaxial with the sun gear.

  According to the present invention, the first gear (sun gear) is provided with one helical meshing convex portion, and the second gear (planetary gear) is provided with a plurality of meshing concave portions with which the meshing convex portions are meshed. The convex portion and the meshing concave portion are each formed in an arc shape in a direction orthogonal to the axial direction of the first gear.

  Therefore, the first gear and the second gear can have an arcuate uneven engagement structure that does not deteriorate the meshing state of each other, and the number of teeth of the second gear is increased while the number of teeth of the first gear is one. Thus, the difference in the number of teeth can be easily increased. Therefore, the reduction ratio can be increased without increasing the size of the reduction mechanism.

It is the perspective view which looked at the motor with a deceleration mechanism from the connector connection part side. It is the perspective view which looked at the motor with a deceleration mechanism from the output shaft side. It is a perspective view explaining the internal structure of a motor with a speed reduction mechanism. It is the perspective view which expanded the meshing part of a pinion gear and a helical gear. It is sectional drawing which follows the AA line of FIG. It is explanatory drawing explaining the detailed shape of a pinion gear and a helical gear. It is explanatory drawing explaining the meshing operation | movement of a pinion gear and a helical gear. FIG. 6 is a diagram corresponding to FIG. 5 showing a second embodiment. FIG. 6 is a diagram corresponding to FIG. 5 showing a third embodiment. FIG. 6 is a diagram corresponding to FIG. 5 showing a fourth embodiment. FIG. 6 is a diagram corresponding to FIG. 5 showing a fifth embodiment. It is explanatory drawing explaining Embodiment 6 (face gear). It is explanatory drawing explaining Embodiment 7 (jam gear). It is a perspective view which shows Embodiment 8 (planetary gear reduction mechanism). It is a disassembled perspective view which shows the planetary gear reduction mechanism of FIG. It is explanatory drawing explaining the specification of the planetary gear reduction mechanism of FIG. It is explanatory drawing explaining the specification (comparative example) of the planetary gear speed-reduction mechanism using an involute gear. It is a perspective view which shows Embodiment 9 (planetary gear reduction mechanism).

  Hereinafter, Embodiment 1 of the present invention will be described in detail with reference to the drawings.

  1 is a perspective view of the motor with a speed reduction mechanism as viewed from the connector connecting portion side, FIG. 2 is a perspective view of the motor with a speed reduction mechanism as viewed from the output shaft side, and FIG. 3 illustrates the internal structure of the motor with the speed reduction mechanism. FIG. 4 is an enlarged perspective view of the meshing portion of the pinion gear and the helical gear, FIG. 5 is a sectional view taken along the line AA in FIG. 4, and FIG. 6 is a diagram for explaining the detailed shapes of the pinion gear and the helical gear. FIG. 7 is an explanatory diagram for explaining the meshing operation of the pinion gear and the helical gear.

  1 and 2 is used as a drive source of a wiper device (not shown) mounted on a vehicle such as an automobile. More specifically, the motor 10 with a speed reduction mechanism is disposed on the front side of a windshield (not shown), and a wiper member (not shown) swingably provided on the windshield is attached to a predetermined windshield. It swings within the wiping range (between the lower inversion position and the upper inversion position).

  The motor 10 with a speed reduction mechanism includes a housing 11 that forms the outline of the motor. Then, as shown in FIG. 3, the brushless motor 20 and the speed reduction mechanism 30 are rotatably accommodated in the housing 11. Here, the housing 11 is formed of an aluminum casing 12 and a plastic cover member 13.

  As shown in FIGS. 1 and 2, the casing 12 is formed in a substantially bowl shape by injection molding a molten aluminum material. Specifically, the casing 12 includes a bottom wall portion 12a, a side wall portion 12b provided integrally therewith, and a case flange 12c provided on the opening side (left side in the drawing) of the casing 12. Yes.

  A cylindrical boss portion 12d that holds the output shaft 34 rotatably is integrally provided at a substantially central portion of the bottom wall portion 12a. A cylindrical bearing member (not shown) called a metal is mounted on the radially inner side of the boss portion 12d, whereby the output shaft 34 can smoothly rotate without rattling with respect to the boss portion 12d. It is like that.

  A plurality of reinforcing ribs 12e extending radially about the boss portion 12d are integrally provided on the radially outer side of the boss portion 12d. These reinforcing ribs 12e are disposed between the boss portion 12d and the bottom wall portion 12a, and are formed in a substantially triangular shape in appearance. These reinforcing ribs 12e enhance the fixing strength of the boss portion 12d with respect to the bottom wall portion 12a, and prevent the occurrence of problems such as the boss portion 12d being inclined with respect to the bottom wall portion 12a.

  Furthermore, a bearing member accommodating portion 12f is integrally provided at a position eccentric from the boss portion 12d of the bottom wall portion 12a. The bearing member accommodating portion 12f is formed in a bottomed cylindrical shape and protrudes in the same direction as the protruding direction of the boss portion 12d. As shown in FIG. 3, a ball bearing 33 that rotatably supports the tip end side of the pinion gear 31 is accommodated inside the bearing member accommodating portion 12f.

  As shown in FIG. 2, a retaining ring 12g is provided between the boss portion 12d and the output shaft 34, thereby preventing the output shaft 34 from rattling in the axial direction of the boss portion 12d. Is done. Therefore, the silence of the motor 10 with the speed reduction mechanism is ensured.

  The cover member 13 forming the housing 11 is formed in a substantially flat plate shape by injection molding a molten plastic material. Specifically, the cover member 13 includes a main body portion 13a and a cover flange 13b provided integrally therewith. The cover flange 13b is abutted against the case flange 12c via a seal member (not shown) such as an O-ring. This prevents rainwater or the like from entering the housing 11.

  Further, the main body 13a of the cover member 13 is integrally provided with a motor accommodating portion 13c that accommodates the brushless motor 20 (see FIG. 3). The motor accommodating portion 13c is formed in a bottomed cylindrical shape and protrudes on the opposite side to the casing 12 side. The motor housing portion 13 c faces the bearing member housing portion 12 f of the casing 12 with the cover member 13 mounted on the casing 12. And the stator 21 (refer FIG. 3) of the brushless motor 20 is fixed inside the motor accommodating part 13c.

  Further, the main body 13a of the cover member 13 is integrally provided with a connector connecting portion 13d to which a vehicle-side external connector (not shown) is connected. One end side of a plurality of terminal members 13e (only one is shown in FIG. 1) for supplying a drive current to the brushless motor 20 is exposed inside the connector connecting portion 13d. A drive current is supplied from the external connector to the brushless motor 20 through these terminal members 13e.

  A control board (not shown) for controlling the rotation state (rotation speed, rotation direction, etc.) of the brushless motor 20 is provided between the other end side of the plurality of terminal members 13e and the brushless motor 20. . Thereby, the wiper member fixed to the front end side of the output shaft 34 is swung within a predetermined wiping range on the windshield. The control board is fixed to the inside of the main body portion 13a of the cover member 13.

  As shown in FIG. 3, the brushless motor 20 accommodated in the housing 11 includes an annular stator (stator) 21. The stator 21 is fixed inside the motor housing portion 13c (see FIG. 1) in the cover member 13 while being prevented from rotating.

  The stator 21 is formed by laminating a plurality of thin steel plates (magnetic bodies), and a plurality of teeth (not shown) are provided on the radially inner side. In these teeth, a U-phase, V-phase, and W-phase coil 21a is wound a plurality of times by concentrated winding or the like. Thus, by alternately supplying a drive current to each coil 21a at a predetermined timing, the rotor 22 provided on the radially inner side of the stator 21 is rotated with a predetermined drive torque in a predetermined rotation direction.

  A rotor (rotor) 22 is rotatably provided on the radially inner side of the stator 21 through a minute gap (air gap). The rotor 22 constitutes a rotating body in the present invention, and includes a rotor body 22a formed by laminating a plurality of thin steel plates (magnetic bodies) and having a substantially cylindrical shape. A cylindrical permanent magnet 22 b is provided on the outer peripheral portion of the rotor 22. Here, the permanent magnet 22b is magnetized so that magnetic poles are alternately arranged in the circumferential direction of N pole, S pole,. The permanent magnet 22b is firmly fixed to the rotor body 22a so as to be integrally rotatable with an adhesive or the like.

  Thus, the brushless motor 20 according to the present embodiment is a brushless motor having an SPM (Surface Permanent Magnet) structure in which the permanent magnet 22b is fixed to the surface of the rotor body 22a. However, not only the brushless motor having the SPM structure but also a brushless motor having an IPM (Interior Permanent Magnet) structure in which a plurality of permanent magnets are embedded in the rotor body 22a may be employed.

  Further, instead of the single permanent magnet 22b formed in a cylindrical shape, a plurality of permanent magnets having a substantially arc-shaped cross section along the direction intersecting the axis of the rotor main body 22a are arranged in the circumferential direction of the rotor main body 22a. The magnetic poles may be arranged at equal intervals so that the magnetic poles are alternately arranged. Furthermore, the number of poles of the permanent magnet 22b can be arbitrarily set according to the specifications of the brushless motor 20, such as 2 poles or 4 poles or more.

  As shown in FIG. 3, the speed reduction mechanism 30 accommodated in the housing 11 includes a pinion gear (first gear) 31 formed in a substantially rod shape, and a helical gear (second gear) 32 formed in a substantially disk shape. And. Here, the axis of the pinion gear 31 and the axis of the helical gear 32 are parallel to each other. Thereby, in the speed reduction mechanism 30, the physique can be made more compact than the worm speed reducer provided with the worm and the worm wheel that intersect with each other.

  The pinion gear 31 is disposed on the input side (drive source side) of the motor 10 with a speed reduction mechanism, and the helical gear 32 is disposed on the output side (drive object side) of the motor 10 with a speed reduction mechanism. That is, the speed reduction mechanism 30 decelerates the high speed rotation of the pinion gear 31 having a small number of teeth to the low speed rotation of the helical gear 32 having a large number of teeth.

  Here, the base end side of the pinion gear 31 is firmly fixed to the rotation center of the rotor main body 22a by press fitting or the like, and the pinion gear 31 rotates integrally with the rotor main body 22a. That is, the pinion gear 31 is rotated by the rotor 22. Further, the tip end side of the pinion gear 31 is rotatably supported by a ball bearing 33. Further, the proximal end side of the output shaft 34 is firmly fixed to the rotation center of the helical gear 32 by press fitting or the like, and the output shaft 34 rotates integrally with the helical gear 32.

  The pinion gear 31 forming the speed reduction mechanism 30 is made of metal and has a shape as shown in FIGS. Specifically, the pinion gear 31 has a pinion main body 31a formed in a substantially columnar shape, the axial base end side is fixed to the rotor main body 22a, and the axial front end side is rotatable to the ball bearing 33. It is supported. That is, the rotation center C1 of the pinion gear 31 (pinion main body 31a) coincides with the rotation center of the rotor main body 22a and the ball bearing 33.

  A spiral tooth (first tooth portion) 31b is integrally provided at a portion of the pinion body 31a facing the helical gear 32 along the axial direction. Specifically, the axial length of the helical tooth 31 b is set to be slightly longer than the axial length of the helical gear 32. As a result, the helical teeth 31b can mesh with the helical gear 32 with certainty. The spiral teeth 31b extend continuously in a spiral shape in the axial direction of the pinion gear 31, and the pinion gear 31 is provided with only one spiral tooth 31b. That is, the number of teeth of the pinion gear 31 is set to “1”.

  As shown in FIG. 5, the helical teeth 31 b are formed so that a cross section along a direction orthogonal to the axial direction of the pinion gear 31 is circular. The center C2 of the helical tooth 31b is eccentric (offset) by a predetermined distance L with respect to the rotation center C1 of the pinion gear 31. That is, the amount of eccentricity of the center C2 with respect to the rotation center C1 is L. Accordingly, the center C2 of the helical tooth 31b follows the first rotation locus OC as the pinion gear 31 rotates. In other words, the first rotation locus OC forms the reference circle of the helical tooth 31b.

  Further, as shown in FIG. 5, an auxiliary line AL is drawn from the rotation center C1 of the pinion gear 31 toward the center C2 of the helical tooth 31b (downward in the figure), and the auxiliary line AL is further connected to the helical tooth. When extending to the surface of 31b, the auxiliary line AL and the surface of the helical tooth 31b intersect. This intersection is the vertex BP of the meshing convex portion 31c. Here, the apex BP is provided on the meshing convex portion 31 c at the radially outer end (surface) of the pinion gear 31. Further, the meshing convex portion 31 c constitutes a meshing portion that is a part of the helical tooth 31 b, and the meshing convex portion 31 c is also helical, and between the adjacent inclined teeth 32 c of the helical gear 32. The engagement recess 32d is inserted (engaged).

  Thus, the meshing convex part 31c is provided in the part near the vertex BP of the helical tooth 31b. The meshing protrusion 31c is formed in an arc shape in a direction orthogonal to the axial direction of the pinion gear 31, and a center of curvature C2 is provided at a position eccentric from the rotation center C1 of the pinion gear 31 by a predetermined distance L. . That is, the center of curvature C2 of the meshing convex portion 31c and the center C2 of the helical tooth 31b coincide with each other.

  Here, the vertex BP of the meshing protrusion 31c follows the second rotation locus PR as the pinion gear 31 rotates. That is, the diameter dimension D1 of the second rotation locus PR is larger than the diameter dimension D2 of the helical tooth 31b (D1> D2).

  FIG. 5 shows a state where the apex BP of the meshing convex portion 31c enters the meshing concave portion 32d of the helical gear 32, that is, a state where the meshing convex portion 31c and the meshing concave portion 32d are meshed with each other.

  The helical gear 32 forming the speed reduction mechanism 30 is made of plastic and has a shape as shown in FIGS. Specifically, the helical gear 32 includes a gear body 32a formed in a substantially disk shape, and the proximal end side of the output shaft 34 is firmly fixed to the center portion of the gear body 32a by press-fitting or the like. A cylindrical portion 32b extending in the axial direction of the output shaft 34 is integrally provided on the outer peripheral portion of the gear body 32a.

  A plurality of oblique teeth (second tooth portions) 32c are integrally provided on the radially outer side of the cylindrical portion 32b so as to be aligned in the circumferential direction of the cylindrical portion 32b. These inclined teeth 32 c are inclined at a predetermined angle with respect to the axial direction of the pinion gear 31, whereby the helical gear 32 is rotated with the rotation of the helical teeth 31 b. Here, the number of inclined teeth 32 c provided on the helical gear 32 is set to “40”. That is, in the present embodiment, the reduction ratio of the reduction mechanism 30 including the pinion gear 31 and the helical gear 32 is “40”. The meshing operation between the pinion gear 31 and the helical gear 32 will be described in detail later.

  As shown in FIGS. 5 and 6, a meshing recess 32 d is provided between adjacent oblique teeth 32 c. Therefore, the meshing recess 32d is also inclined at a predetermined angle with respect to the axial direction of the pinion gear 31 as in the case of the inclined teeth 32c. And the meshing convex part 31c of the pinion gear 31 enters into the meshing recessed part 32d, and it meshes | engages.

  Here, the engagement recess 32 d is formed in a circular shape (substantially arc shape) along a direction orthogonal to the axial direction of the pinion gear 31, and the center of curvature C <b> 3 is disposed on the reference circle TC of the helical gear 32. In addition, the diameter dimension SR of the meshing recess 32d is slightly larger than the diameter dimension D2 of the spiral tooth 31b (SR> D2).

  The reference circle TC of the helical tooth 31b (= first rotation locus OC) circumscribes the reference circle TC of the helical gear 32. Therefore, the diameter of the helical gear 32 is R (twice the distance between the rotation center C4 of the helical gear 32 and the first rotation locus OC) at the center of the inclined tooth 32c along the circumferential direction of the helical gear 32. In this embodiment, the cross-sectional shape of the helical tooth 31b is circular following the shape of the meshing convex portion 31c. Therefore, although the pinion gear 31 is easy to manufacture, a thick portion T having a predetermined thickness exists on the side opposite to the apex BP side of the helical tooth 31b.

  Therefore, in order to prevent interference (contact) between the helical teeth 31b and the inclined teeth 32c, the teeth of the inclined teeth 32c are reduced by the escape amount E so that the helical teeth 31b and the inclined teeth 32c are not in contact with each other. Take H is set. Here, the tooth depth H of the inclined teeth 32c is the height from the root circle BC passing through the deepest portion of the meshing recess 32d. Further, the angle θ formed by the adjacent meshing recesses 32d is “9” in the present embodiment because the number of teeth of the helical gear 32 is “40” and the number of meshing recesses 32d is also “40”. It has become.

  In summary, the shapes of the pinion gear 31 and the helical gear 32 are determined so as to satisfy the following various expressions, respectively.

  Specifically, the shape of the pinion gear 31 is determined based on the following formula (1).

(D2 ÷ 2 + L) × 2 = D1 (1)
D2: Diameter dimension of the helical tooth 31b L: Eccentricity D1: Diameter dimension of the second rotation locus PR The shape of the helical gear 32 is determined based on the following formulas (2) to (4).

L × 2 × reduction ratio = R (2)
L: Eccentric amount R: Diameter dimension of the center of the inclined tooth 32c Reduction ratio: “40” in the present embodiment
That is, as shown in the above equation (2), the reduction ratio of the pinion gear 31 and the helical gear 32 (reduction mechanism 30) is the first distance between the center of curvature C2 of the meshing protrusion 31c and the rotation center C1 of the pinion gear 31. (= The eccentric amount L) and the ratio of the second distance (= R / 2) between the center of curvature C3 of the meshing recess 32d and the center of rotation C4 of the helical gear 32.

SR = D2 + α (3)
SR: Diameter dimension of the meshing recess 32d D2: Diameter dimension of the helical tooth 31b α: Minute amount D2 ÷ 2-L × 2 + β = E (4)
D2: Diameter dimension of the helical tooth 31b L: Eccentric amount β: Minute amount E: Amount of relief of the tooth of the inclined tooth 32c Here, the minute amounts α and β in the above formulas (3) and (4) are the meshing protrusions. This is a setting value for smoothly meshing the 31c and the meshing recess 32d, and is appropriately set to a very small optimum value according to the detailed shape (a minute curve, a taper shape, etc.) of the inclined tooth 32c. .

  Next, the operation of the speed reduction mechanism 30 formed as described above, that is, the meshing operation of the pinion gear 31 and the helical gear 32 will be described in detail with reference to the drawings.

  The state indicated by “0 degree” in FIG. 7 is the same as the state shown in FIG. In this state, the apex BP of the meshing convex part 31 c in the pinion gear 31 is in a state of entering the meshing concave part 32 d of the helical gear 32. That is, the meshing convex part 31c and the meshing concave part 32d are in a state of being meshed with each other.

  During the operation of the speed reduction mechanism 30, the state in which the meshing convex portion 31c and the meshing concave portion 32d are meshed with each other, that is, the state shown in “0 degree” in FIG. 7 (the state shown in FIG. 5) is spiral. It moves gradually in the axial direction of the tooth 31b. Then, since the meshing recess 32 d is inclined with respect to the axial direction of the pinion gear 31, the helical gear 32 is rotated while being decelerated from the pinion gear 31. Thus, the helical gear 32 rotates with the rotation of the pinion gear 31.

  Here, focusing only on a portion along the axial direction of the helical tooth 31b (for example, a portion along the line AA in FIG. 4), the pinion gear 31 rotates counterclockwise in the state shown at “0 degree” in FIG. When rotating in the direction, the apex BP of the meshing protrusion 31c is also rotated in the counterclockwise direction. As a result, the meshing protrusion 31c rotates in the order of “75 degrees” → “133 degrees” → “190 degrees” → “227 degrees” → “266 degrees” and gets over one oblique tooth 32c. Thereafter, as shown in “360 degrees” in FIG. 7, the meshing convex portion 31 c rotated once is meshed with the adjacent meshing concave portion 32 d (see the movement state indicated by white circles in the drawing).

  Thus, when the helical tooth 31b rotates once, the helical gear 32 is rotated by one of the inclined teeth 32c (one of the meshing recesses 32d). That is, while the pinion gear 31 rotates once, the helical gear 32 is rotated by 9 degrees. In other words, when the pinion gear 31 rotates 40 times, the helical gear 32 gradually rotates once (= reduction ratio “40”). As a result, the helical gear 32 is rotated with a rotational torque (high torque) 40 times that of the pinion gear 31.

  As described above in detail, according to the first embodiment, the pinion gear 31 is provided with one helical engagement protrusion 31c, and the helical gear 32 is provided with a plurality of engagement recesses 32d with which the engagement protrusions 31c are engaged. The meshing convex portion 31c and the meshing concave portion 32d are each formed in an arc shape in a direction orthogonal to the axial direction of the pinion gear 31.

  Therefore, the pinion gear 31 and the helical gear 32 can have an arcuate concave / convex meshing structure that does not deteriorate the meshing state, and the number of teeth of the helical gear 32 is increased while the number of teeth of the pinion gear 31 is one (this In the embodiment, “40”) The difference in the number of teeth can be easily increased. Therefore, the reduction ratio can be increased without increasing the size of the reduction mechanism 30.

  Further, according to the first embodiment, the axis of the pinion gear 31 and the axis of the helical gear 32 are parallel to each other, so that the physique is more than that of the worm speed reducer provided with a worm and a worm wheel that intersect with each other. It can be made more compact.

  Next, various embodiments according to the present invention will be described in detail with reference to the drawings. Note that portions having the same functions as those in the first embodiment described above are denoted by the same reference numerals, and detailed description thereof is omitted.

  8 is a diagram corresponding to FIG. 5 showing the second embodiment, FIG. 9 is a diagram corresponding to FIG. 5 showing the third embodiment, and FIG. 10 is a diagram corresponding to FIG. 5 showing the fourth embodiment. 11 is a diagram corresponding to FIG. 5 showing the fifth embodiment, FIG. 12 is an explanatory diagram for explaining the sixth embodiment (face gear), and FIG. 13 is for explaining the seventh embodiment (spot gear). FIG. 14 is a perspective view showing the eighth embodiment (planetary gear reduction mechanism), FIG. 15 is an exploded perspective view showing the planetary gear reduction mechanism of FIG. 14, and FIG. 16 is a planetary gear reduction of FIG. FIG. 17 is an explanatory view for explaining the specifications of the mechanism, FIG. 17 is an explanatory view for explaining the specifications (comparative example) of the planetary gear speed reduction mechanism using involute gears, and FIG. 18 shows the ninth embodiment (planetary gear speed reduction mechanism). Each perspective view is shown.

[Embodiment 2]
As shown in FIG. 8, in the speed reduction mechanism 40 according to the second embodiment, the shape of the helical tooth (first tooth portion) 41 provided in the pinion gear 31 and the inclined tooth (second tooth portion) provided in the helical gear 32. ) 42 is different in shape. Specifically, interference (contact) with the inclined teeth 42 is prevented at the end portion (the lower surface in the drawing) opposite to the vertex BP with respect to the center of curvature C2 of the meshing convex portion 31c of the helical tooth 41. An escape portion 43 is provided. The escape portion 43 is formed by a flat surface provided on the opposite side of the vertex BP from the center of curvature C2 of the meshing convex portion 31c.

  Further, the tooth tip of the inclined tooth 42 is extended to the inside of the arcuate space 44 (shaded portion in the figure) formed by providing the escape portion 43, and thereby the tooth tip of the inclined tooth 42 is escaped. It is made to adjoin to part 43. Specifically, the tooth depth H1 of the inclined teeth 42 is approximately 1.5 times larger than the tooth height H (see FIG. 6) of the inclined teeth 32c of the first embodiment (H1> H).

  Also in the second embodiment formed as described above, the same operational effects as in the first embodiment can be obtained. In addition, in Embodiment 2, since the escape portion 43 is provided in the helical tooth 41, the helical tooth 41 can be reduced in size and weight. Further, the tooth depth H1 of the inclined teeth 42 can be set to a sufficient height, the meshing strength between the meshing convex portion 31c and the meshing concave portion 32d can be improved, and power transmission with higher torque can be achieved.

[Embodiment 3]
As shown in FIG. 9, in the speed reduction mechanism 50 according to the third embodiment, only the shape of the helical tooth (first tooth portion) 51 provided in the pinion gear 31 is different. Specifically, the helical tooth 51 is formed so that a cross section along a direction orthogonal to the axial direction of the pinion gear 31 is substantially elliptical. Specifically, it has a shape in which a predetermined amount of both sides of the helical tooth 51 is scraped off around an auxiliary line AL connecting the apex BP of the meshing projection 31c and the rotation center C1 of the pinion gear 31. More specifically, each of the pair of arc-shaped spaces 52 (shaded portions) on both sides of the spiral tooth 51 around the auxiliary line AL has a shape that is scraped off. At this time, the arcuate portion having the apex BP of the meshing convex portion 31c is scraped off so that the center of curvature becomes the same C2 as in the first embodiment.

  In the third embodiment formed as described above, the same operational effects as in the first embodiment can be obtained. In addition, in the third embodiment, the volume of the pair of arcuate spaces 52 can be reduced as compared with the helical teeth 31b of the speed reduction mechanism 30 according to the first embodiment. It becomes possible to reduce the size and weight.

[Embodiment 4]
As shown in FIG. 10, in the speed reduction mechanism 60 according to the fourth embodiment, only the shape of the helical tooth (first tooth portion) 61 provided in the pinion gear 31 is different. Specifically, the helical tooth 61 is formed so that a cross section along a direction orthogonal to the axial direction of the pinion gear 31 has a substantially fan shape (substantially onigiri shape). Specifically, a predetermined amount of portions on both sides of the helical tooth 61 and near the vertex BP are scraped off by a predetermined amount around the auxiliary line AL connecting the vertex BP of the meshing protrusion 31c and the rotation center C1 of the pinion gear 31. It has a different shape. Specifically, the shape of the pair of arc-shaped spaces 62 (shaded portions) on both sides of the helical tooth 61 around the auxiliary line AL and near the vertex BP is cut off. At this time, the arcuate portion having the apex BP of the meshing convex portion 31c is scraped off so that the center of curvature becomes the same C2 as in the first embodiment.

  In the fourth embodiment formed as described above, the same operational effects as in the first embodiment can be obtained. In addition, in the fourth embodiment, the volume of the pair of arcuate spaces 62 can be reduced as compared with the spiral teeth 31b of the speed reduction mechanism 30 according to the first embodiment. It becomes possible to reduce the size and weight. Moreover, since there are few parts to cut off compared with the speed reduction mechanism 50 which concerns on Embodiment 3, it is not necessary to reduce the rigidity of the helical tooth 61. FIG.

  As in the third and fourth embodiments, the auxiliary line AL may not be symmetrical on both sides of the auxiliary line AL, but may be asymmetric on both sides of the auxiliary line AL. Further, the shape of the portion to be scraped off is not limited to the arc shape as in the third and fourth embodiments, but may be a polygonal shape or the like, and the shape is not limited.

[Embodiment 5]
As shown in FIG. 11, in the speed reduction mechanism 70 according to the fifth embodiment, the shape of the helical tooth (first tooth portion) 71 provided on the pinion gear 31 and the inclined tooth (second tooth portion) provided on the helical gear 32 are illustrated. ) 72 shape is different. Specifically, the helical tooth 71 is formed in a coil spring shape, and the rotation center C1 of the pinion gear 31 is disposed within the cross-sectional range of the helical tooth 71 along the direction orthogonal to the axial direction of the pinion gear 31. Absent. Here, the diameter dimension D3 of the helical tooth 71 is smaller than the diameter dimension D2 of the helical tooth 31b of the first embodiment (D3 <D2).

  Further, the center of curvature C5 of the meshing protrusion 31c is arranged at a position away from the rotation center C1 of the pinion gear 31 as compared with the first embodiment. Specifically, the separation distance between the center of curvature C5 of the meshing protrusion 31c and the rotation center C1 of the pinion gear 31 is set to L1, and this eccentric amount L1 is a distance approximately twice the eccentric amount L of the first embodiment. It has become. Accordingly, the center C5 of the helical tooth 71 (= the center of curvature C5 of the meshing convex portion 31c) is a first rotation locus having a larger diameter than the first rotation locus OC (see FIG. 5) as the pinion gear 31 rotates. It follows OC1.

  Furthermore, since the center C5 of the helical tooth 71 follows the first rotation locus OC1 having a large diameter, the depth of the inclined tooth 72 of the helical gear 32 is set low as H2. Specifically, the tooth depth H2 of the inclined teeth 72 is approximately 2/3 the size of the tooth height H (see FIG. 5) of the inclined teeth 32c of the first embodiment (H2 <H).

  In the fifth embodiment formed as described above, the same operational effects as those of the first embodiment can be obtained. In addition, in the fifth embodiment, since the volume of the helical tooth 71 can be further reduced, the helical tooth 71 can be further reduced in size and weight.

[Embodiment 6]
As shown in FIG. 12, in the speed reduction mechanism 80 according to the sixth embodiment, only the point that the gear meshed with the pinion gear 31 is a face gear 81 instead of the helical gear 32 as shown in FIG. Is different. That is, in the present embodiment, the face gear 81 constitutes the second gear in the present invention. Specifically, the axis of the face gear 81 and the axis of the pinion gear 31 are orthogonal to each other, forming a so-called staggered shaft gear mechanism.

  The face gear 81 is formed in an annular shape, and on its surface, as shown in FIG. 12, a plurality of inclined teeth (second teeth) 82 and a plurality of meshing recesses provided between adjacent inclined teeth 82. 83. The plurality of inclined teeth 82 and the plurality of meshing recesses 83 are inclined with respect to the axial direction of the pinion gear 31 and are arranged in the circumferential direction of the face gear 81.

  Here, although not shown in detail, the meshing recess 83 is formed in an arc shape in a direction orthogonal to the axial direction of the pinion gear 31, and is formed in an arc shape similarly to the meshing recess 32d (see FIG. 5) of the first embodiment. Has been. As a result, as in the first embodiment, the meshing convex portion 31 c of the pinion gear 31 is meshed with the meshing concave portion 83 of the face gear 81.

  The high speed rotation of the pinion gear 31 in the direction of the arrow R1 in the figure is the low speed rotation of the face gear 81 in the direction of the arrow R2 in the figure. Then, the torque that has been increased in torque is output from an output section (not shown) provided on the face gear 81 toward a drive object (not shown).

  Also in the sixth embodiment formed as described above, the same operational effects as in the first embodiment can be obtained.

[Embodiment 7]
As shown in FIG. 13, the speed reduction mechanism 90 according to the seventh embodiment has a structure in which a pair of speed reduction mechanisms 30 including a pinion gear 31 and a helical gear 32 are abutted so as to be mirror images of each other with the abutting portion TP as a boundary. adopt. In other words, the pair of helical gears 32 that face each other becomes a spur gear (second gear) 91 in an integrated state. The angle teeth (second tooth portion) 91a of the helical gear 91 are formed so as to have a substantially V-shaped appearance by bevel teeth 32c facing each other so as to be mirror-image symmetrical with each other. Therefore, a meshing recess 32d facing each other is provided between the adjacent chevron teeth 91a so that the appearance is substantially V-shaped.

  Furthermore, in the pair of pinion gears 31 that face each other, a double pinion gear (first gear) 92 is formed in an integrated state. The double pinion gear 92 is provided with a pair of helical teeth 31b facing each other so as to be mirror-image symmetric with each other. In other words, the spiral teeth 31b have the spiral directions opposite to each other. And the meshing convex part 31c of these helical teeth 31b has meshed | engaged with the meshing recessed part 32d between adjacent mountain teeth 91a, respectively.

  In the seventh embodiment formed as described above, the same operational effects as those of the first embodiment can be obtained. In addition to this, the seventh embodiment employs a structure in which the pair of speed reduction mechanisms 30 are abutted so as to be mirror-symmetric with each other, that is, the structure of a spur gear, which is shown by arrows F1 and F2 in FIG. Thus, the thrust force that attempts to move the spur gear 91 and the double pinion gear 92 in the axial direction can be canceled (eliminated).

That is, even if the double pinion gear 92 is rotated in the direction of the solid line arrow in the drawing or the direction of the broken line arrow in the drawing, the double pinion gear 92 and the blind gear 91 rotated thereby do not move in the axial direction. . Therefore, the structure on the housing side that accommodates the double pinion gear 92 and the blind gear 91 can be further simplified.
[Embodiment 8]
As shown in FIGS. 14 to 16, in the eighth embodiment, the motor 100 with a speed reduction mechanism whose overall shape is formed in a substantially cylindrical shape. The motor 100 with a speed reduction mechanism includes a motor portion 200 formed in a substantially cylindrical shape and a speed reduction mechanism portion 300 similarly formed in a substantially cylindrical shape, which are provided coaxially with each other.

  The motor unit 200 includes a bottomed cylindrical motor housing 210 that forms an outline of the motor 100 with a speed reduction mechanism, and the brushless motor 20 is accommodated in the motor housing 210. The stator 21 forming the brushless motor 20 is fixed to the inner wall of the motor housing 210 with an adhesive or the like (not shown), and the rotor 22 is rotatable on the radially inner side of the stator 21 through a predetermined gap. Is provided. Then, the axial base end portion of the drive shaft 220 is firmly fixed to the rotation center of the rotor 22 by press-fitting or the like. Thus, the motor unit 200 includes the drive shaft 220 that is rotated by the rotor 22.

  The speed reduction mechanism unit 300 includes a bottomed cylindrical gear housing (housing) 310 that forms an outline of the motor 100 with the speed reduction mechanism. The gear housing 310 includes a bottom wall portion 311 formed in a substantially disc shape, and a cylindrical wall portion 312 provided integrally with the bottom wall portion 311. Further, an insertion hole 313 through which the axial base end side (lower side in FIG. 15) of the drive shaft 220 is inserted is formed in the center portion of the bottom wall portion 311. Here, on the radially inner side of the insertion hole 313, a first bearing B <b> 1 that rotatably supports the axial base end side of the drive shaft 220 is fixed. Thereby, the drive shaft 220 can rotate smoothly with respect to the gear housing 310. The first bearing B1 employs a cylindrical sliding bearing called a so-called metal.

  Furthermore, a planetary gear speed reduction mechanism 320 as a speed reduction mechanism is accommodated in the gear housing 310. The planetary gear reduction mechanism 320 includes a sun gear (first gear) 330 rotated by the drive shaft 220, a pair of planetary gears (second gear) 340 rotated by the sun gear 330, and a pair of these planetary gears. An internal gear (ring gear) 350 meshed with the gear 340.

  The sun gear 330 is exactly the same as the above-described pinion gear 31 (see FIG. 4), and includes helical teeth 31b and meshing protrusions 31c. The axial base end portion of the sun gear 330 is provided integrally with the axial distal end portion of the drive shaft 220. That is, the drive shaft 220 and the sun gear 330 are each formed of one member (made of metal) and are arranged coaxially with each other. Therefore, the sun gear 330 is rotated by the drive shaft 220.

  The pair of planetary gears 340 are disposed so as to face each other around the sun gear 330 (see FIG. 16), and revolve around the sun gear 330. These planetary gears 340 are the same as each other, and the same peripheral teeth 32c as the helical gear 32 (see FIG. 3) described above are provided on the outer peripheral portion of the planetary gear 340. A meshing concave portion 32d into which the meshing convex portion 31c of the sun gear 330 enters (meshes) is formed between the adjacent inclined teeth 32c. Therefore, the planetary gear 340 is rotated by the sun gear 330.

  Further, the pair of planetary gears 340 are rotatably supported by the carrier 360, respectively. The carrier 360 is formed by assembling the first member 370 and the second member 380 with each other. The first member 370 includes a first main body portion 371 formed in a substantially rectangular plate shape. An insertion hole 372 through which the distal end side in the axial direction of the drive shaft 220 is inserted in a non-contact state is formed at the longitudinal center of the first main body 371. Further, a pair of support shafts 373 that rotatably support the pair of planetary gears 340 are provided on both sides in the longitudinal direction of the first main body 371. The sun gear 330 is sandwiched between the planetary gears 340 rotatably supported by these support shafts 373. Thereby, one meshing convex part 31c provided in the sun gear 330 is meshed with the meshing concave part 32d provided in each of the pair of planetary gears 340 in the same manner as in the state shown in FIG. .

  The second member 380 forming the carrier 360 includes a second main body 381 formed in a substantially rectangular plate shape. An insertion hole (not shown) is formed in the center portion in the longitudinal direction of the second main body portion 381 so that the axial tip portion of the sun gear 330 is inserted in a non-contact state. Further, a pair of support holes 382 for supporting the ends of the pair of support shafts 373 are formed on both sides in the longitudinal direction of the second main body 381. An opening end portion (not shown) of the output shaft 383 formed in a bottomed cylindrical shape is fixed to a portion corresponding to the insertion hole of the second main body portion 381. And the 2nd bearing B2 which supports the axial direction front-end | tip part of the sun gear 330 rotatably is fixed to the part of the opening end part of the output shaft 383, and the part of the insertion hole of the 2nd main-body part 381. Thereby, the sun gear 330 can be smoothly rotated with respect to the output shaft 383. The second bearing B2 also employs a cylindrical sliding bearing called a so-called metal. As described above, the carrier 360 rotatably supports the pair of planetary gears 340 and includes the output shaft 383 coaxial with the sun gear 330.

  Further, an inner gear 350 formed in a substantially cylindrical shape is fixed inside the cylindrical wall portion 312 forming the gear housing 310 so as not to be relatively rotatable. In addition, a plurality of internal teeth 351 with which the inclined teeth 32 c of the pair of planetary gears 340 are meshed are provided on the inner peripheral portion of the internal gear 350. These inner teeth 351 are also formed in the same shape as the inclined teeth 32 c provided on the planetary gear 340.

  Further, the opening side portion (upper portion in FIG. 15) of the gear housing 310 is closed by a gear cover 390 formed in a substantially disk shape. Thus, the assembled planetary gear speed reduction mechanism 320 can be operated inside the gear housing 310 without rattling and without being disassembled. In addition, an insertion hole 391 is formed in the center portion of the gear cover 390 so that the output shaft 383 is inserted in a non-contact state. A third bearing B3 that rotatably supports the output shaft 383 is fixed inside the insertion hole 391 in the radial direction. As a result, the output shaft 383 can rotate smoothly with respect to the gear cover 390. The third bearing B3 also employs a cylindrical sliding bearing called a so-called metal.

  The specifications of the planetary gear speed reduction mechanism 320 formed as described above are as shown in the table of FIG. Specifically, in the planetary gear speed reduction mechanism 320 of the present invention, the module representing the tooth size is “2”, the number of teeth of the sun gear 330 is “1”, and the number of teeth of the planetary gear 340 is “12”. The number of teeth of the internal gear 350 is “25”, and the reduction ratio is relatively large “26”. The physique of the planetary gear speed reduction mechanism 320 (the outer diameter of the internal gear 350) is “φ70”, and it was found that the planetary gear speed reduction mechanism 320 can be made relatively small.

  On the other hand, the specification of the planetary gear speed reduction mechanism (1) using the involute gear as close as possible to the specification of the planetary gear speed reduction mechanism 320 of the present invention is as shown in the table of FIG. Specifically, in the planetary gear reduction mechanism (1) of the comparative example, the module representing the tooth size is “0.7”, the number of teeth of the sun gear (2) is “9”, and the planetary gear ( The number of teeth of 3) is “72”, the number of teeth of the internal gear (4) is “153”, and the reduction ratio is “18”, which is smaller than the planetary gear reduction mechanism 320 of the present invention described above. ing. And the physique of the planetary gear reduction mechanism (1) (the outer diameter of the internal gear (4)) is “φ120”, which is larger than the planetary gear reduction mechanism 320 of the present invention described above. .

  In other words, in order to obtain the same physique and the same reduction ratio as the planetary gear reduction mechanism 320 of the present invention, the planetary gear reduction mechanism (1) using the involute gear is structurally impossible, and the same reduction ratio is obtained. If you want to get a ratio, you have to increase the size. Thus, it has been found that the planetary gear speed reduction mechanism 320 of the present invention is much more advantageous in reducing the size and weight than the planetary gear speed reduction mechanism (1) using an involute gear.

In the eighth embodiment formed as described above, the same operational effects as those of the first embodiment can be obtained.
[Embodiment 9]
As shown in FIG. 18, the ninth embodiment is different from the eighth embodiment only in the structure of the planetary gear speed reduction mechanism 400 (speed reduction mechanism). Note that portions having the same functions as those in the eighth embodiment are denoted by the same symbols, and detailed description thereof is omitted.

  In the planetary gear reduction mechanism 400 of the ninth embodiment, a pair of planetary gears 340 is rotatably supported on the bottom wall portion 311 of the gear housing 310. That is, in the ninth embodiment, the bottom wall portion 311 constitutes the support member in the present invention. The bottom wall portion 311 is provided with a pair of support shafts 373 that rotatably support the pair of planetary gears 340. That is, the pair of planetary gears 340 performs a rotation motion that rotates about the pair of support shafts 373, but does not perform a revolving motion that rotates about the sun gear 330.

  In the planetary gear speed reduction mechanism 400 of the ninth embodiment, an internal gear 350 is rotatably provided with respect to the gear housing 310. Specifically, the internal gear 350 is disposed in the gear housing 310 in a state where the outer peripheral wall of the internal gear 350 is not in contact with the inner peripheral wall of the cylindrical wall portion 312. That is, in the eighth embodiment, the pair of planetary gears 340 supported by the carrier 360 (see FIG. 15) is rotatable with respect to the gear housing 310, and the internal gear 350 is fixed to the gear housing 310. On the other hand, in the ninth embodiment, contrary to the eighth embodiment, the pair of planetary gears 340 are fixed to the gear housing 310 by the bottom wall portion 311, and the internal gear 350 is rotatable with respect to the gear housing 310. It has become.

  An output shaft 383 that is coaxial with the sun gear 330 rotates with the internal gear 350. Specifically, the output shaft 383 is fixed to the internal gear 350 via a flat plate-shaped power transmission member 410. The power transmission member 410 is formed in a substantially rectangular shape, and fixing holes 411 to which the fixing pins 420 are fixed are provided on both sides in the longitudinal direction. One side in the axial direction of the pair of fixing pins 420 is fixed to the fixing hole 411. Further, the other axial side of the pair of fixing pins 420 is fixed to a fixing hole (not shown) at the end of the internal gear 350 on one axial side. Thus, the power transmission member 410 rotates together with the internal gear 350 as the internal gear 350 rotates.

  An opening end portion (not shown) of the output shaft 383 is fixed to the central portion in the longitudinal direction of the power transmission member 410. An insertion hole (not shown) similar to the insertion hole 372 (see FIG. 15) provided in the first main body 371 is provided in a portion where the output shaft 383 of the power transmission member 410 is fixed. .

  As described above, in the ninth embodiment, the output shaft 383 rotates together with the internal gear 350. That is, the output shaft 383 coaxial with the sun gear 330 is provided on the internal gear 350 via the power transmission member 410.

  In the ninth embodiment formed as described above, the same operational effects as those of the first embodiment can be obtained.

  It goes without saying that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention. For example, in the third and fourth embodiments, the vicinity of the meshing convex portion 31c is scraped off so that the center of curvature of the arc-shaped portion having the vertex BP of the meshing convex portion 31c is the same as C2 in the first embodiment. Although shown, the present invention is not limited to this. For example, in the same manner as in the fifth embodiment (see FIG. 11), the meshing convex portion 31c is arranged so that the center of curvature of the arc-shaped portion having the apex BP of the meshing convex portion 31c is greatly decentered from the rotation center C1 of the pinion gear 31. You may make it scrape off the vicinity.

  In each of the above embodiments, the reduction gears 30, 40, 50, 60, 70, 80, 90 and the planetary gear reduction mechanisms 320, 400 (the motors 10 and 100 with a reduction mechanism) are mounted on the vehicle. However, the present invention is not limited to this, but can be applied to other drive sources such as a power window device, a sunroof device, and a seat lifter device.

  Further, in each of the above-described embodiments, the speed reduction mechanisms 30, 40, 50, 60, 70, 80, 90 and the planetary gear speed reduction mechanisms 320, 400 are driven by the brushless motor 20. The present invention is not limited to this, and a brushed motor is adopted instead of the brushless motor 20, and the reduction gears 30, 40, 50, 60, 70, 80, 90 and the planetary gear reduction mechanism 320, 400 can also be driven.

  In addition, the material, shape, dimensions, number, installation location, and the like of each component in each of the above embodiments are arbitrary as long as the present invention can be achieved, and are not limited to each of the above embodiments.

DESCRIPTION OF SYMBOLS 10 Motor with reduction mechanism 11 Housing 12 Casing 12a Bottom wall part 12b Side wall part 12c Case flange 12d Boss part 12e Reinforcement rib 12f Bearing member accommodating part 12g Retaining ring 13 Cover member 13a Main body part 13b Cover flange 13c Motor accommodating part 13d Connector connection part 13e Terminal member 20 Brushless motor 21 Stator 21a Coil 22 Rotor (rotating body)
22a Rotor body 22b Permanent magnet 30 Reduction mechanism 31 Pinion gear (first gear, drive shaft)
31a Pinion body 31b Spiral tooth (first tooth)
31c Meshing convex part 32 Helical gear (2nd gear)
32a Gear body 32b Cylindrical part 32c Inclined tooth (second tooth part)
32d Engaging recess 33 Ball bearing 34 Output shaft 40 Reduction mechanism (Embodiment 2)
41 Spiral teeth (first teeth)
42 Inclined teeth (second tooth)
43 Escape portion 44 Arc space 50 Reduction mechanism (Embodiment 3)
51 Spiral tooth (first tooth)
52 Arc-shaped space 60 Reduction mechanism (Embodiment 4)
61 Spiral tooth (first tooth)
62 Arc space 70 Deceleration mechanism (Embodiment 5)
71 Spiral tooth (first tooth)
72 Inclined teeth (second tooth)
80 Deceleration mechanism (Embodiment 6)
81 Face gear (second gear)
82 Inclined teeth (second tooth)
83 meshing recess 90 deceleration mechanism (Embodiment 7)
91 Blind gear (second gear)
91a Mountain tooth (second tooth)
92 Double pinion gear (first gear)
DESCRIPTION OF SYMBOLS 100 Motor with reduction mechanism 200 Motor part 210 Motor housing 220 Drive shaft 300 Reduction mechanism part 310 Gear housing (housing)
311 Bottom wall (support member)
312 Cylindrical wall portion 313 Insertion hole 320 Planetary gear speed reduction mechanism (speed reduction mechanism)
330 Sun gear (first gear)
340 Planetary gear (second gear)
350 Internal gear 351 Internal tooth 360 Carrier 370 First member 371 First main body 372 Insertion hole 373 Support shaft 380 Second member 381 Second main body 382 Support hole 383 Output shaft 390 Gear cover 391 Insertion hole 400 Planetary gear reduction mechanism (deceleration) mechanism)
410 Power transmission member 411 Fixing hole 420 Fixing pin (1) Planetary gear reduction mechanism (comparative example)
(2) Sun gear (comparative example)
(3) Planetary gear (comparative example)
(4) Internal gear (comparative example)
AL auxiliary line B1 first bearing B2 second bearing B3 third bearing BC tooth bottom circle BP vertex of meshing convex portion 31c C1 rotation center of pinion gear 31 C2 center of curvature of meshing convex portion 31c, center of helical tooth 31b C3 meshing concave portion Center of curvature of 32d C4 Center of rotation of helical gear 32 C5 Center of curvature of meshing convex portion 31c, center of helical tooth 71 (Embodiment 5)
D1 Diameter dimension of second rotation locus PR D2 Diameter dimension of spiral tooth 31b D3 Diameter dimension of spiral tooth 71 (Embodiment 5)
E Escape amount of inclined tooth 32c H, H1, H2 Tooth L, L1 Eccentricity (first distance)
OC, OC1 First rotation locus PR Second rotation locus R Diameter diameter of the center of the inclined tooth 32c (second distance)
SR Diameter dimension of meshing concave portion 32d T Thick portion TC Reference circle of helical gear 32 TP Butting portion α, β Small amount θ Angle formed by adjacent meshing concave portions 32d

Claims (12)

A speed reduction mechanism including a first gear and a second gear,
A first tooth portion provided on the first gear and extending in a spiral shape in the axial direction of the first gear;
A meshing convex portion provided on the first tooth portion, formed in an arc shape in a direction orthogonal to the axial direction of the first gear, and provided with a center of curvature at a position eccentric from the rotation center of the first gear; ,
A plurality of second teeth provided on the second gear, inclined with respect to the axial direction of the first gear and arranged in the circumferential direction of the second gear;
A meshing recess provided between the adjacent second tooth portions, formed in an arc shape in a direction orthogonal to the axial direction of the first gear, and meshing with the meshing projection;
Having
Reduction mechanism. The speed reduction mechanism according to claim 1,
The reduction ratio of the first gear and the second gear is
Equal to the ratio of the first distance between the center of curvature of the meshing projection and the center of rotation of the first gear and the second distance between the center of curvature of the meshing recess and the center of rotation of the second gear. Has become,
Reduction mechanism. In the speed reduction mechanism according to claim 1 or 2,
The first tooth portion is
At the radially outer end of the first gear, the apex provided on the meshing protrusion,
An escape portion that is provided at an end opposite to the vertex with respect to the center of curvature of the meshing convex portion and prevents interference with the second tooth portion,
With
Reduction mechanism. In the speed reduction mechanism according to any one of claims 1 to 3,
The axis of the first gear and the axis of the second gear are parallel,
Reduction mechanism. In the speed reduction mechanism according to any one of claims 1 to 4,
Further, a housing that forms an outer shell of the speed reduction mechanism is provided,
The first gear is a sun gear;
The second gear is a plurality of planetary gears;
A carrier rotatably supporting the planetary gear and provided with an output shaft coaxial with the sun gear;
An internal gear fixed to the housing, the internal gear including internal teeth that mesh with the second teeth provided on the planetary gear;
Having
Reduction mechanism. In the speed reduction mechanism according to any one of claims 1 to 4,
Further, a housing that forms an outer shell of the speed reduction mechanism is provided,
The first gear is a sun gear;
The second gear is a plurality of planetary gears;
A support member rotatably supporting the planetary gear and fixed to the housing;
An internal gear provided with an internal tooth meshed with the second tooth portion provided on the planetary gear, and provided with an output shaft coaxial with the sun gear;
Having
Reduction mechanism. A motor having a rotating body;
A first gear rotated by the rotating body;
A second gear rotated by the first gear;
A motor with a speed reduction mechanism,
A first tooth portion provided on the first gear and extending in a spiral shape in the axial direction of the first gear;
A meshing convex portion provided on the first tooth portion, formed in an arc shape in a direction orthogonal to the axial direction of the first gear, and provided with a center of curvature at a position eccentric from the rotation center of the first gear; ,
A plurality of second teeth provided on the second gear, inclined with respect to the axial direction of the first gear and arranged in the circumferential direction of the second gear;
A meshing recess provided between the adjacent second tooth portions, formed in an arc shape in a direction orthogonal to the axial direction of the first gear, and meshing with the meshing projection;
An output shaft provided at the rotation center of the second gear;
Having
Motor with reduction mechanism. The motor with a speed reduction mechanism according to claim 7,
The reduction ratio of the first gear and the second gear is
Equal to the ratio of the first distance between the center of curvature of the meshing projection and the center of rotation of the first gear and the second distance between the center of curvature of the meshing recess and the center of rotation of the second gear. Has become,
Motor with reduction mechanism. The motor with a speed reduction mechanism according to claim 7 or claim 8,
The first tooth portion is
At the radially outer end of the first gear, the apex provided on the meshing protrusion,
An escape portion that is provided at an end opposite to the vertex with respect to the center of curvature of the meshing convex portion and prevents interference with the second tooth portion,
With
Motor with reduction mechanism. The motor with a speed reduction mechanism according to any one of claims 7 to 9,
The axis of the first gear and the axis of the second gear are parallel,
Motor with reduction mechanism. A motor having a rotating body;
A sun gear rotated by the rotating body;
A plurality of planetary gears rotated by the sun gear;
An internal gear meshed with the planetary gear;
A motor with a reduction mechanism provided,
A housing that houses the sun gear, the planetary gear, and the internal gear;
A first tooth portion provided on the sun gear and extending spirally in the axial direction of the sun gear;
A meshing convex portion provided on the first tooth portion, formed in an arc shape in a direction orthogonal to the axial direction of the sun gear, and provided with a center of curvature at a position eccentric from the rotation center of the sun gear;
A plurality of second teeth provided on the planetary gear, inclined with respect to the axial direction of the sun gear, and arranged in the circumferential direction of the planetary gear;
A meshing recess provided between the adjacent second tooth portions, formed in an arc shape in a direction orthogonal to the axial direction of the sun gear, and meshing with the meshing projection;
A carrier rotatably supporting the planetary gear and provided with an output shaft coaxial with the sun gear;
Have
The internal gear includes internal teeth with which the second tooth portion provided on the planetary gear is engaged, and is fixed to the housing.
Motor with reduction mechanism. A motor having a rotating body;
A sun gear rotated by the rotating body;
A plurality of planetary gears rotated by the sun gear;
An internal gear meshed with the planetary gear;
A motor with a reduction mechanism provided,
A housing that houses the sun gear, the planetary gear, and the internal gear;
A first tooth portion provided on the sun gear and extending spirally in the axial direction of the sun gear;
A meshing convex portion provided on the first tooth portion, formed in an arc shape in a direction orthogonal to the axial direction of the sun gear, and provided with a center of curvature at a position eccentric from the rotation center of the sun gear;
A plurality of second teeth provided on the planetary gear, inclined with respect to the axial direction of the sun gear, and arranged in the circumferential direction of the planetary gear;
A meshing recess provided between the adjacent second tooth portions, formed in an arc shape in a direction orthogonal to the axial direction of the sun gear, and meshing with the meshing projection;
A support member rotatably supporting the planetary gear and fixed to the housing;
Have
The internal gear includes an internal tooth with which the second tooth portion provided on the planetary gear is engaged, and has an output shaft coaxial with the sun gear.
Motor with reduction mechanism.

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