JP2014016017A - Speed reduction mechanism and motor rotational force transmission device including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a speed reduction mechanism capable of achieving extension of the service life of a bearing, and a motor rotational force transmission device including the same.SOLUTION: A speed reduction transmission mechanism 5 comprises: a motor shaft 42 having an eccentric part 42a; an input member 50 rotatably supported by the outer peripheral surface of the eccentric part 42a via a ball bearing 54 and comprising an external gear having a plurality of pin insertion holes 50b arranged around the axis at equal intervals; a rotational force application member 52 engaged with the input member 50 and comprising an internal gear in which the number of teeth thereof is larger than that of the external gear; and a plurality of output members 53 receiving the rotational force applied to the input member 50 by the rotational force application member 52, outputting the rotational force to a differential case 30 as the rotational force for the same, and inserted into the plurality of pin insertion holes 50b. The input member 50 has annular projections 50e, 50f projecting in the axial direction. The circumferential surfaces of the projections 50e, 50f are formed as rolling-contact surfaces 500e, 500f which are in rolling-contact with the differential case 30.

Description

  The present invention relates to a speed reduction mechanism suitable for use in, for example, an electric vehicle having an electric motor as a drive source, and a motor rotational force transmission device including the same.

  A conventional motor rotational force transmission device includes an electric motor that generates a motor rotational force, and a deceleration transmission mechanism that transmits a driving force based on the motor rotational force of the electric motor to a differential mechanism. (See, for example, Patent Document 1).

  The electric motor has a motor shaft that is rotated by the electric power of the in-vehicle battery, and is disposed on the axis of the deceleration transmission mechanism.

  The deceleration transmission mechanism has a shaft portion (rotating shaft with an eccentric portion) that is spline-fitted to the motor shaft of the electric motor, and a pair of deceleration transmission portions that are positioned around the rotating shaft with the eccentric portion. It is disposed between the moving mechanism (difference case) and connected to the motor shaft and the difference case. The deceleration transmission mechanism is accommodated in the housing together with the electric motor and the differential mechanism.

  With the above configuration, the motor shaft of the electric motor is rotated by the electric power of the in-vehicle battery, and accordingly, the motor rotational force is transmitted from the electric motor to the differential mechanism via the speed reduction transmission mechanism, and the left and right wheels are transmitted from this differential mechanism. To be distributed.

  By the way, the deceleration transmission part of this type of motor torque transmission device is a pair of disk-shaped revolving members that revolve by rotation of the motor shaft of the electric motor (rotation of the rotating shaft with an eccentric part). There are a plurality of outer pins for applying a rotation force, and a plurality of inner pins for outputting the rotation force of the revolution member as a rotational force to the differential mechanism inside the outer pins.

  The pair of revolving members have a center hole that opens in the direction of the center axis, and a plurality of pin insertion holes that are arranged at equal intervals around the center axis of the center hole, and are supported by the eccentric part of the rotary shaft with the eccentric part. It is rotatably supported via a (cam-side bearing).

  The plurality of outer pins are arranged at equal intervals around the axis of the motor shaft and are attached to the housing of the speed reduction transmission mechanism.

  The plurality of inner pins are inserted through a plurality of pin insertion holes in the revolving member, arranged at equal intervals around the axis of the motor shaft, and attached to the differential case. A bearing (pin side bearing) for reducing contact resistance between the inner peripheral surfaces of the plurality of pin insertion holes in the pair of revolution members is attached to the plurality of inner pins.

JP 2007-218407 A

  In the motor rotational force transmission device shown in Patent Document 1, it is not only necessary to prepare a plurality of outer pins, but the outer peripheral portion of the revolving member needs to have a complicated shape, which is uneconomical.

  Therefore, the revolution member is an external gear, and the rotation force imparting member for imparting a rotation force to the revolution member is an internal gear, and the number of teeth of the internal gear is larger than the number of teeth of the external gear. It is conceivable to eliminate the above-mentioned uneconomical as a number.

  However, if such a reduction gear transmission mechanism using external gears and internal gears is used in a motor torque transmission device of an automobile, the revolution speed of the external gear, which is a revolution member, becomes relatively high. Therefore, a load due to centrifugal force is applied to the cam-side bearing, resulting in a problem that the life of the cam-side bearing is reduced.

  Accordingly, an object of the present invention is to provide a speed reduction mechanism capable of extending the life of a bearing and a motor rotational force transmission device including the speed reduction mechanism.

  In order to achieve the above object, the present invention provides a speed reduction mechanism (1) to (8) and a motor torque transmission device including the speed reduction mechanism.

(1) From a rotating shaft having an eccentric portion, and an external gear having a plurality of through-holes supported rotatably on the outer peripheral surface of the eccentric portion of the rotating shaft via a bearing and arranged in parallel at equal intervals around the axis An input member that is engaged with the input member, and a rotation force applying member that is an internal gear having a number of teeth larger than the number of teeth of the external gear, and the rotation force applying member is applied to the input member. A plurality of output members that receive a rotation force and output to the output object as rotational force, and are inserted through the plurality of through holes, respectively, and the input member has an annular protrusion protruding in the axial direction. The reduction mechanism in which the peripheral surface of the convex part is formed of a rolling contact surface that makes rolling contact with the output target or the rotation force applying member as a contact target and the contact target side.

(2) In the reduction mechanism according to (1), the input member includes a curved surface on which the rolling contact surface receives an axial load from the contact target side and is applied to the bearing as a preload.

(3) In the speed reduction mechanism according to (1) or (2), the input member includes an annular movable member interposed between the rolling contact surface and the contact target, and an axis line from the movable member side. It arrange | positions in the position which receives the elastic force by an elastic member in the direction.

(4) In the speed reduction mechanism according to (3), the input member has the rolling contact surface as a convex surface, and the rolling contact surface is brought into rolling contact with a tapered surface or a concave surface provided on the movable member.

(5) In the speed reduction mechanism according to any one of (1) to (4), the input member has the rolling contact surface disposed as an inner peripheral surface of the convex portion on a radially outer side of the plurality of output members. Has been.

(6) In the speed reduction mechanism according to any one of (1) to (5), in the input member, the rolling contact surface is disposed as an outer peripheral surface of the convex portion on a radially inner side of the plurality of output members. ing.

(7) In the speed reduction mechanism according to any one of (1) to (6), the plurality of output members are a pair of flanges as components of the output target that are opposed to each other via the input member. And a connecting member that connects the pair of collars.

(8) In a motor rotational force transmission device comprising: an electric motor that generates a motor rotational force; and a speed reduction mechanism that decelerates the motor rotational force of the electric motor and outputs a driving force. 1) A motor rotational force transmission device that is a reduction mechanism according to any one of (7).

  According to the present invention, the life of the bearing can be increased.

The top view shown in order to demonstrate the outline of the vehicle carrying the motor rotational force transmission apparatus which concerns on the 1st Embodiment of this invention. Sectional drawing shown in order to demonstrate the whole motor rotational force transmission apparatus which concerns on the 1st Embodiment of this invention. FIG. 3 is a cross-sectional view schematically showing the deceleration transmission mechanism of the motor torque transmission device according to the first embodiment of the present invention. Sectional drawing which expands and shows the principal part (M part of FIG. 2) of the motor rotational force transmission apparatus which concerns on the 1st Embodiment of this invention. (A) And (b) is sectional drawing shown in order to demonstrate the locus | trajectory of the rolling contact point between the input member and contact object of the motor rotational force transmission apparatus which concerns on the 1st Embodiment of this invention. (A) shows the locus of the rolling contact point of one input member, and (b) shows the locus of the rolling contact point of the other input member. Sectional drawing which expands and shows the principal part of the motor rotational force transmission apparatus which concerns on the 2nd Embodiment of this invention. Sectional drawing which shows the principal part of the motor rotational force transmission apparatus which concerns on the 1st Embodiment of this invention and 2nd Embodiment as a modification.

[First embodiment]
Hereinafter, a speed reduction mechanism according to a first embodiment of the present invention and a motor torque transmission device including the speed reduction mechanism will be described in detail with reference to the drawings.

  FIG. 1 schematically shows a four-wheel drive vehicle. As shown in FIG. 1, a four-wheel drive vehicle 101 uses a front-wheel-side power system that uses a drive source as an engine, and a rear-wheel-side power system that uses a drive source as an electric motor. , An engine 102, a transaxle 103, a pair of front wheels 104, and a pair of rear wheels 105.

  The motor rotational force transmission device 1 is disposed in a power system on the rear wheel side of the four-wheel drive vehicle 101 and is supported by a vehicle body (not shown) of the four-wheel drive vehicle 101.

  The motor rotational force transmission device 1 transmits a driving force based on the motor rotational force of the electric motor 4 (described later) to the pair of rear wheels 105. As a result, the motor rotational force of the electric motor 4 is output to the rear axle shaft 106 (a pair of rear wheels 105) via the deceleration transmission mechanism 5 and the rear differential 3 (both described later), and the pair of rear wheels 105 are driven. Details of the motor rotational force transmission device 1 and the like will be described later.

  The engine 102 is disposed in the power system on the front wheel side of the four-wheel drive vehicle 101. As a result, the driving force of the engine 102 is output to the front axle shaft 107 (a pair of front wheels 104) via the transaxle 103, and the pair of front wheels 104 are driven.

(Whole structure of the motor torque transmission device 1)
FIG. 2 shows the entire motor torque transmission device. As shown in FIG. 2, the motor rotational force transmission device 1 includes a housing 2 having an axis O ₁ ( _first axis) as an axis of a rear axle shaft 106 (shown in FIG. 1), and a driving force based on the motor rotational force. The rear differential 3 distributed to the rear wheels 105 (shown in FIG. 1), the electric motor 4 that generates a motor rotational force for operating the rear differential 3, and the motor rotational force of the electric motor 4 is decelerated to reduce the driving force. It is mainly composed of a deceleration transmission mechanism 5 that transmits to the rear differential 3.

(Configuration of housing 2)
The housing 2 includes a rotation force applying member 52 to be described later, a first housing element 20 that houses the rear differential 3, a second housing element 21 that houses the electric motor 4, and a one-side opening of the second housing element 21. And a third housing element 22 that closes a portion (an opening on the side opposite to the opening on the first housing element 20 side).

The first housing element 20 is disposed on one side in the axial direction of the housing 2 (left side in FIG. 2), and is entirely formed by a stepped bottomed cylindrical member that opens to the second housing element 21 side. The bottom of the first housing element 20 is provided with a shaft insertion hole 20a through which the rear axle shaft 106 (shown in FIG. 1) is inserted, and an inner flange 20b protruding in the radial direction on the inner peripheral surface of the shaft insertion hole 20a. ing. The inner flange 20b is provided with an annular notch 20c that opens on the flange end surface on the second housing element 21 side of both flange end surfaces and the inner peripheral surface of the shaft insertion hole 20a. On the opening end surface of the first housing element 20, an annular convex portion 23 that protrudes toward the second housing element 21 is integrally provided. The outer peripheral surface of the convex portion 23 is formed by a circumferential surface having an outer diameter smaller than the maximum outer diameter of the first housing element 20 and having the axis O ₄ (fourth axis) as the central axis. The inner peripheral surface of the first housing element 20 is disposed between the outer peripheral surface of the rear axle shaft 106 and a seal member 24 that seals the shaft insertion hole 20a. In FIG. 2, the axis O ₄ is drawn to coincide with the axis O ₁ .

The second housing element 21 is disposed at an intermediate portion in the axial direction of the housing 2, and is entirely formed of a bottomless cylindrical member that opens in both directions of the axial line O ₄ . A stepped inner flange 21 a interposed between the electric motor 4 and the speed reduction transmission mechanism 5 is integrally provided at one side opening of the second housing element 21 (opening on the first housing element 20 side). ing. An annular member 25 for attaching a race is attached to the inner peripheral surface of the inner flange 21a. An annular convex portion 27 that protrudes toward the first housing element 20 is integrally provided on one side opening end surface of the second housing element 21 (opening end surface on the first housing element 20 side). The outer peripheral surface of the convex portion 27 is a circumferential surface having an outer diameter that is smaller than the maximum outer diameter of the second housing element 21 and substantially the same as the outer diameter of the convex portion 23 and that has the axis O ₄ as the central axis. Is formed.

  The third housing element 22 is disposed on the other side in the axial direction of the housing 2 (right side in FIG. 2), and is entirely formed of a stepped bottomed cylindrical member that opens to the second housing element 21 side. A shaft insertion hole 22 a through which the rear axle shaft 106 is inserted is provided at the bottom of the third housing element 22. A cylindrical portion 22b for attaching a stator that protrudes toward the electric motor 4 is integrally provided on the inner opening periphery of the shaft insertion hole 22a. The inner peripheral surface of the third housing element 22 is disposed between the outer peripheral surface of the rear axle shaft 106 and a seal member 28 that seals the shaft insertion hole 22a. The third housing element 22 is provided with an annular step surface 22 c that restricts the movement of the ball bearing 46 (outer ring 461) to the side opposite to the speed reduction transmission mechanism 5.

(Configuration of rear differential 3)
The rear differential 3 includes a differential mechanism of a bevel gear type having a differential case (contact object) 30, a pinion gear shaft 31, a pair of pinion gears 32, and a pair of side gears 33, and one side (left side in FIG. 2) of the motor rotational force transmission device 1. ).

  As a result, the rotational force of the differential case 30 is distributed from the pinion gear shaft 31 to the side gear 33 via the pinion gear 32, and from the side gear 33 to the left and right rear wheels 105 (shown in FIG. 1) via the rear axle shaft 106 (shown in FIG. 1). ).

  On the other hand, when a driving resistance difference occurs between the left and right rear wheels 105, the rotational force of the differential case 30 is differentially distributed to the left and right rear wheels 105 by the rotation of the pinion gear 32.

The differential case 30 is disposed on the axis O ₅ (fifth axis), and is rotatable via the ball bearing 34 on the first housing element 20 and via the ball bearing 35 on the motor shaft 42 of the electric motor 4. It is supported by. The differential case 30 receives the driving force based on the motor rotational force of the electric motor 4 from the deceleration transmission mechanism 5 and rotates around the axis O ₅ . In FIG. 2, the axis O ₅ is drawn to coincide with the axis O ₁ .

  The differential case 30 includes a housing space 30a that houses the differential mechanism (pinion gear shaft 31, pinion gear 32, and side gear 33), and a pair of shaft insertion holes 30b that communicate with the housing space 30a and connect the left and right rear axle shafts 106 respectively. Is provided.

  In addition, the differential case 30 is integrally provided with an annular flange 30 c as a first flange portion facing the speed reduction transmission mechanism 5. An annular step surface 30d that restricts the movement of the ball bearing 34 (inner ring 340) toward the motor shaft 42 is provided at one end in the axial direction of the differential case 30, and the speed reduction transmission mechanism 5 is provided at the other end in the axial direction. An annular concave hole 30e that opens to the side is provided. An annular step surface 300e that restricts the movement of the ball bearing 35 (outer ring 351) toward the differential case 30 is provided in the recessed hole 30e.

The flange 30c, the pin insertion hole 300c of a plurality (six in this embodiment) in parallel at equal intervals about the axis O ₁ is provided. An annular concave groove 301c that opens along the axis O ₅ (O ₁ ) is provided on the motor-side end surface of the flange 30c on the electric motor 4 side outside the plurality of output members 53 (described later). Yes. Further, the motor side end surface of the flange 30c, the concave groove 302c of the annular opening along the axis O ₁ at the radially inner side of the plurality of output members 53 to the electric motor 4 side. On the electric motor 4 side of the flange 30c, a flange 30f is disposed as a second flange portion facing the flange end surface.

In one concave groove 301c, an annular movable member 70 interposed between the flange 30c and one input member 50 (described later) is disposed so as to be able to advance and retract with the tip portion exposed. The exposed end portion of the movable member 70 is provided with an annular concave surface 70a having a predetermined radius of curvature R = R ₁ (shown in FIG. 4) by cutting out a portion extending over the outer peripheral surface and a part of the front end surface. It has been. A circle having a spring force (elastic force) f = f ₁ (shown in FIG. 4) toward the electric motor 4 along the axis O ₁ between the back surface of the movable member 70 and the groove bottom of the one concave groove 301c. An annular elastic member 71 is interposed. The elastic member 71 applies a spring force f = f ₁ to one input member 50. As the elastic member 71, for example, a leaf spring having a corrugated cross section is used. A wave washer may be used instead of the leaf spring having a corrugated cross section.

In the other concave groove 302c, an annular movable member 72 interposed between the flange 30c and the one input member 50 is disposed so as to be able to advance and retreat with the tip portion exposed. A predetermined radius of curvature R = R ₂ (R ₂ = R ₁ : shown in FIG. 4) is formed in the exposed end portion of the movable member 72 by notching a portion extending over a part of the inner peripheral surface and the tip surface. An annular concave surface 72a is provided. Between the rear and the groove bottom of one groove 302c of the movable member 72, similarly to the elastic member 71, the spring force of the electric motor 4 side along the axis O ₁ (the elastic force) f = f 1 _(Fig. 4), an annular elastic member 73 having an interposition is interposed. The elastic member 73 applies a spring force f = f ₂ to one input member 50. As the elastic member 73, for example, a leaf spring having a cross-sectional wave shape is used. A wave washer may be used instead of the leaf spring having a corrugated cross section.

The flange 30f is connected to the flange 30c by a plurality of output members 53 on the axis of the motor shaft 42, and is rotatably supported on the outer peripheral surface of the motor shaft 42 via an annular spacer 37 and a ball bearing 38. Is formed by a stepped annular member. The flange 30f is provided with an accommodation hole 300f through which the motor shaft 42 is inserted and the spacer 37 and the ball bearing 38 are accommodated. Furthermore, the flange 30f movement of the pin insertion hole 301f of the plurality (six in this embodiment) in parallel at equal intervals about the axis O _1, and the electric motor 4 side of the ball bearing 38 (outer ring 381) An annular convex portion 302f that restricts the inside of the housing hole 300f is provided. An annular concave groove 303f that opens along the axis O ₅ (O ₁ ) on the rear differential 3 side on the radially outer side of a plurality of output members 53 (described later) is provided on the differential-side end surface portion of the flange 30f. Yes. In addition, an annular concave groove 304 f that opens along the axis O ₁ is provided on the rear differential 3 side on the radial inner side of the plurality of output members 53 on the differential side end surface portion of the flange 30 f.

An annular movable member 74 interposed between the flange 30f and the other input member 51 (described later) is disposed in one concave groove 303f so as to be able to advance and retreat with its tip portion exposed. The exposed end of the movable member 74 is provided with an annular concave surface 74a having a predetermined radius of curvature R = R ₃ (shown in FIG. 4) by cutting out a portion extending over a part of the outer peripheral surface and the tip surface. It has been. A circle having a spring force (elastic force) f = f ₃ (shown in FIG. 4) toward the rear differential 3 along the axis O ₁ between the back surface of the movable member 74 and the groove bottom of the one concave groove 303f. An annular elastic member 75 is interposed. The elastic member 75 applies a spring force f = f ₃ to the other input member 51. As the elastic member 75, for example, a plate spring having a cross-sectional wave shape is used. A wave washer may be used instead of the leaf spring having a corrugated cross section.

An annular movable member 76 interposed between the flange 30f and the other input member 51 is disposed in the other recessed groove 304f so as to be able to advance and retreat with the tip portion exposed. A predetermined radius of curvature R = R ₄ (R ₄ = R ₃ : shown in FIG. 4) is formed in the exposed end portion of the movable member 76 by notching a portion extending over a part of the inner peripheral surface and the tip surface. An annular concave surface 76a is provided. Like the elastic member 75, between the back surface of the movable member 76 and the groove bottom of one of the concave grooves 304f, a spring force (elastic force) f = f ₄ toward the rear differential 3 along the axis O ₁ (FIG. 4), an annular elastic member 77 is interposed. The elastic member 77 applies a spring force f = f ₄ to the other input member 51. As the elastic member 77, for example, a plate spring having a corrugated cross section is used. A wave washer may be used instead of the leaf spring having a corrugated cross section.

The pinion gear shaft 31 is disposed on the axis L perpendicular to the axis O ₁ in the accommodation space 30a of the differential case 30, and the rotation around the axis L and the movement in the axis L direction are restricted by pins (not shown).

  The pair of pinion gears 32 is rotatably supported by the pinion gear shaft 31 and is accommodated in the accommodating space 30 a of the differential case 30.

  The pair of side gears 33 are housed in the housing space 30a of the differential case 30 and are connected by spline fitting to a rear axle shaft 106 (shown in FIG. 1) that passes through the shaft insertion hole 30b. The pair of side gears 33 mesh with the pair of pinion gears 32 with their gear shafts orthogonal to the gear shafts of the pair of pinion gears 32.

(Configuration of electric motor 4)
The electric motor 4 includes a stator 40, a rotor 41, and a motor shaft 42 (a motor shaft with an eccentric portion), and is disposed on the other side (right side in FIG. 2) of the motor rotational force transmission device ₁ on the axis O1. The rear differential 3 is connected via a speed reduction transmission mechanism 5. The electric motor 4 has a stator 40 connected to an ECU (Electronic Control Unit: not shown). In the electric motor 4, the stator 40 receives a control signal from the ECU, generates a motor rotational force for operating the rear differential 3, and rotates the rotor 41 together with the motor shaft 42.

  The stator 40 is disposed on the outer peripheral side of the electric motor 4 and is attached to the inner flange 21 a of the second housing element 21 by mounting bolts 43.

  The rotor 41 is disposed on the inner peripheral side of the electric motor 4 and is attached to the outer peripheral surface of the motor shaft 42.

The motor shaft 42 has one end on the inner peripheral surface of the annular member 25 via a ball bearing 44 and a sleeve 45, and the other end on the inner peripheral surface of the third housing element 22. And are supported rotatably. The motor shaft 42 is disposed on the axis O _1, the whole is formed by a cylindrical shaft member for inserting the rear axle shaft 106 (shown in Figure 1).

An annular step surface 42 c that restricts the movement of the ball bearing 35 (inner ring 350) toward the speed reduction transmission mechanism 5 is provided at one end in the axial direction of the motor shaft 42. In addition, at one end portion in the axial direction of the motor shaft 42, an eccentric portion 42a having a planar circular shape having an axis O ₂ (second axis) eccentrically parallel to the axis (axis O ₁ ) with an eccentric amount δ _1. , And a plane circular eccentric portion 42b having an axis O ′ ₂ (second axis) eccentrically parallel to the axis O ₁ with an eccentric amount δ ₂ (δ ₁ = δ ₂ = δ). . Then, the one of the eccentric portion 42a and the other of the eccentric portion 42b, is disposed in a position parallel with a regular intervals (180 °) about the axis O _1. That is, the one eccentric portion 42a and the other eccentric portion 42b have the same distance from the axis O ₂ to the axis O ₁ and the distance from the axis O ′ ₂ to the axis O ₁ , and the axis O ₂ and the axis O ′. ₂ is arranged on the outer peripheral surface of the motor shaft 42 so as to make the distance around the axis O ₁ equal to 2. Further, the eccentric portion 42a and the eccentric portion 42b is disposed in a position parallel along the direction of the axis O _1.

  The eccentric portion 42a is provided with a step surface 42e that restricts the movement of the inner ring 540 of the ball bearing 54 toward the electric motor 4 side.

  Similarly, the eccentric portion 42b is provided with a step surface 42g that restricts movement of the inner ring 560 of the ball bearing 56 toward the rear differential 3 side.

  A resolver 47 serving as a rotation angle detector interposed between the outer peripheral surface of the motor shaft 42 and the inner peripheral surface of the cylindrical portion 22b is disposed at the other end portion in the axial direction of the motor shaft 42. A sleeve 63 that restricts the movement of the inner ring 460 toward the speed reduction transmission mechanism 5 between the rotor 41 of the electric motor 4 and the ball bearing 46 (inner ring 460) is disposed at the other axial end of the motor shaft 42. It is arranged intervening. The resolver 47 has a stator 470 and a rotor 471 and is accommodated in the third housing element 22. The stator 470 is attached to the inner peripheral surface of the cylindrical portion 22b, and the rotor 471 is attached to the outer peripheral surface of the motor shaft 42.

(Configuration of deceleration transmission mechanism 5)
FIG. 3 shows the entire deceleration transmission mechanism. FIG. 4 shows a main part (bearing mechanism) of the motor torque transmission device. 5A and 5B show the locus of the rolling contact point between the input member and the output target side. In the present embodiment, the deceleration transmission mechanism is an eccentric oscillating speed reducing mechanism, and is an involute speed reducing mechanism with a small number of teeth among the eccentric oscillating speed reducing mechanisms. A large reduction ratio can be obtained by using this eccentric oscillating speed reduction mechanism. As shown in FIGS. 2 to 4, the speed reduction transmission mechanism 5 includes a pair of input members 50, 51, a rotation force applying member 52, and an output mechanism 53 </ b> A (a plurality of output members 53), and the rear differential 3 and the electric motor. 4 is interposed between the two. As described above, the deceleration transmission mechanism 5 decelerates the motor rotational force of the electric motor 4 and transmits the driving force to the rear differential 3.

One input member 50 is an external gear having a center hole 50a with the axis O ₃ (third axis) as the center axis, is disposed on the rear differential 3 side of the other input member 51, and is center hole 50a. Is supported rotatably on the outer peripheral surface of the eccentric portion 42 a via a ball bearing 54. The ball bearing 54 has two races 540 and 541 (inner ring 540 and outer ring 541) arranged inside and outside thereof, and rolling elements 542 that roll between the inner ring 540 and the outer ring 541. The inner ring 540 is attached to the outer peripheral surface of the eccentric portion 42a by, for example, an interference fit, and the outer ring 541 is attached to the inner peripheral surface of the center hole 50a, for example, by a clearance fit. The one input member 50 is disposed at a position where the elastic force from the movable member 70 to the elastic member 71 and the elastic force from the movable member 72 to the elastic member 73 are received on the electric motor 4 side. Then, the one input member 50 receives a motor rotational force from the electric motor 4 and performs a circular motion (revolution motion around the axis O ₁ ) in the directions of arrows m ₁ and m ₂ having an eccentricity δ. 2 and 3, the axis O ₃ is drawn to coincide with the axis O ₂ . FIG. 4 shows a state where centrifugal force F = F ₁ is applied to _one input member 50 and ball bearing 54.

One input member 50 is provided with a plurality (six in this embodiment) of pin insertion holes (through holes) 50b arranged in parallel at equal intervals around the axis O ₃ (axis O ₂ ). The hole diameter of the pin insertion hole 50 b is set to be larger than the dimension obtained by adding the outer diameter of the needle roller bearing 55 to the outer diameter of the output member 53.

The outer peripheral surface of one of the input member 50, the external teeth 50c is provided with an involute tooth profile of the pitch circle having a center axis corresponding to the axis O _2. Number of teeth _{Z 1} of the external teeth 50c is set to, for example, _Z 1 = 195.

An annular inner flange 50d that protrudes from the inner peripheral surface of the center hole 50a and restricts the movement of the ball bearing 54 (outer ring 541) toward the rear differential 3 is provided at the end portion on the rear differential side of one input member 50. It has been. In addition, the rear differential side end of one of the input member 50, the convex portions 50e, 50f are provided to protrude along the axis O ₂ to the rear differential 3 side.

One convex part 50e is arrange | positioned at the radial direction outer side of the several output member 53, and the whole is formed of the annular member. The inner peripheral surface of one of the convex portion 50e has a curvature radius R = R _5, are formed at the contact surface 500e rolling consisting convex curved surface in rolling contact with the concave surface 70a of the movable member 70. In addition, the rolling contact surface 500e of the one convex portion 50e is supported on the concave surface 70a of the movable member 70 in the radial direction. Accordingly, when a load due to the centrifugal force F = F ₁ generated based on the circular motion is applied to one input member 50, a part of the load is transferred from the rolling contact surface 500e of the one convex portion 50e to the concave surface of the movable member 70. 70a is received at a rolling contact point a (shown in FIG. 5A). Figure in 5 (a), the upper track (the axis _{O 1} of the rolling contact point a between the concave 70a of the rolling contact surface 500e and the movable member 70 of the one-dot chain line _{A 1} is one of the convex portion 50e (FIG. 4) A circle centered on the point). Also, one of the convex portion 50e is rolling contact surface 500e has a spring due to the reaction force P = _{P 1} and the elastic member 71 by rolling contact of the movable member 70 of the axial load (one input member 50 from the concave 70a of the movable member 70 Force f = f ₁ ), a reaction force P = P ₁ and a spring force f = f ₁ are applied as preload to the ball bearing 54 from the inner flange 50d of one input member 50. The radius of curvature R = R ₅ of the rolling contact surface 500e is set to be smaller than the radius of curvature R = R ₁ (R ₁ > R ₅ ) of the concave surface 70a of the movable member 70.

The other convex part 50f is arrange | positioned at the radial inside of the several output member 53, and the whole is formed of the annular member. The outer peripheral surface of the other convex portion 50f has a radius of curvature R = R _6, it is formed at the contact surface 500f rolling consisting convex curved surface in rolling contact with the concave surface 72a of the movable member 72. In the other convex portion 50 f, the rolling contact surface 500 f is supported by the concave surface 72 a of the movable member 72 in the radial direction. As a result, when a load due to the centrifugal force F = F ₁ generated based on the circular motion is applied to one input member 50, a part of this load is transferred from the rolling contact surface 500f of the other convex portion 50f to the concave surface of the movable member 72. 72a receives at the rolling contact point b (shown in FIG. 5 (a)). Figure 5 (a), the dashed line _{A 2} and the other of the projections (4) concave 72a of the rolling contact surface 500f and the movable member 72 of the 50f rolling contact point b of the trajectory between the (upper axis _{O 1} A circle centered on the point). The spring by the other of the convex portion 50f is rolling contact surface 500f reaction force P = _{P 2} and the elastic member 73 from the concave 72a by rolling contact of the movable member 72 of the axial load (one of the input member 50 of the movable member 72 Force f = f ₂ ), a reaction force P = P ₂ and a spring force f = f ₂ are applied as preload to the ball bearing 54 from the inner flange 50d of one input member 50. The radius of curvature R = R ₆ of the rolling contact surface 500f is set to be smaller than the radius of curvature R = R ₂ (R ₂ > R ₆ ) of the concave surface 72a of the movable member 72.

The other input member 51 is composed of an external gear having a center hole 51a having the axis O ′ ₃ (third axis) as a center axis, is disposed on the electric motor 4 side of the one input member 50, and has a center hole. 51a is rotatably supported on the outer peripheral surface of the eccentric portion 42b via a ball bearing 56. The ball bearing 56 includes two races 560 and 561 (an inner ring 560 and an outer ring 561) arranged inside and outside thereof, and rolling elements 562 that roll between the inner ring 560 and the outer ring 561. The inner ring 540 is attached to the outer peripheral surface of the eccentric portion 42a by, for example, an interference fit, and the outer ring 541 is attached to the inner peripheral surface of the center hole 50a, for example, by a clearance fit. The other input member 51 is disposed at a position where the elastic force from the movable member 74 to the elastic member 75 and the elastic force from the movable member 76 to the elastic member 77 are received on the rear differential 3 side. The other input member 51 receives a motor rotational force from the electric motor 4 and performs a circular motion (revolution motion around the axis O ₁ ) in the directions of arrows m ₁ and m ₂ having an eccentricity δ. 2 and 3, the axis O ′ ₃ is drawn to coincide with the axis O ′ ₂ . In FIG. 4, the centrifugal force F = F ₂ is applied to the other input member 51 and the ball bearing 56.

The other input member 51 is provided with a plurality (six in this embodiment) of pin insertion holes (through holes) 51b arranged in parallel at equal intervals around the axis O ′ ₃ (axis O ′ ₂ ). The hole diameter of the pin insertion hole 51 b is set to be larger than the dimension obtained by adding the outer diameter of the needle roller bearing 57 to the outer diameter of the output member 53.

The outer peripheral surface of the other of the input member 51, the outer teeth 51c is provided with an involute tooth profile of the pitch circle having a center axis corresponding to the axis _O'2. Number of teeth _{Z 2} of the external teeth 51c is set to, for example, _Z 2 = 195.

An annular inner flange 51 d that protrudes from the inner peripheral surface of the center hole 51 a and restricts the movement of the ball bearing 56 (outer ring 561) toward the electric motor 4 is provided at the motor side end of the other input member 51. ing. In addition, the rear differential side end of one of the input member 50, the convex portions 51e, 51f are provided to protrude to the rear differential 3 side along the axis O _2.

One convex part 51e is arrange | positioned at the radial direction outer side of the several output member 53, and the whole is formed of the annular member. The inner peripheral surface of one of the convex portion 51e has a curvature radius R = R _7, are formed at the contact surface 510e rolling consisting convex curved surface in rolling contact with the concave surface 74a of the movable member 74. Then, in the one convex portion 51 e, the rolling contact surface 510 e is supported in the radial direction by the concave surface 74 a of the movable member 74. Accordingly, when a load due to the centrifugal force F = F ₂ generated based on the circular motion is applied to the other input member 51, a part of the load is transferred from the rolling contact surface 510e of the one convex portion 51e to the concave surface of the movable member 74. 74a is received at the rolling contact point c (shown in FIG. 5B). Figure in 5 (b), the upper track (the axis _{O 1} of the rolling contact point c between the concave 74a of the one-dot chain line _{A 3} is a rolling contact surface 510e of the one convex portion 51e movable member 74 (shown in FIG. 4) A circle centered on the point). Also, one of the convex portion 51e is rolling contact surface 510e has a spring due to the reaction force P = _{P 3} and the elastic member 75 from the concave 74a by rolling contact of the movable member 74 of the axial load (the other of the input member 51 of the movable member 74 Force f = f ₃ ), a reaction force P = P ₃ and a spring force f = f ₃ are applied as preload to the ball bearing 56 from the inner flange 51d of the other input member 51. The radius of curvature R = R ₇ of the rolling contact surface 510e is set to be smaller than the radius of curvature R = R ₃ (R ₃ > R ₇ ) of the concave surface 74a of the movable member 75.

The other convex part 51f is arrange | positioned at the radial inside of the several output member 53, and the whole is formed of the annular member. The outer peripheral surface of the other convex portion 51f has a radius of curvature R = R _8, it is formed at the contact surface 510f rolling consisting convex curved surface in rolling contact with the concave surface 76a of the movable member 76. In the other convex portion 51 f, the rolling contact surface 510 f is supported in the radial direction by the concave surface 76 a of the movable member 76. Accordingly, when a load due to the centrifugal force F = F ₂ generated based on the circular motion is applied to the other input member 51, a part of the load is transferred from the rolling contact surface 510f of the other convex portion 51f to the concave surface of the movable member 76. 76a is received at the rolling contact point d (shown in FIG. 5B). Figure in 5 (b), the upper track (the axis _{O 1} of the rolling contact point d between the concave 76a of the one-dot chain line _{A 4} is a rolling contact surface 510f of the other convex portion 51f movable member 76 (shown in FIG. 4) A circle centered on the point). Also, the other convex portion 51f, the rolling contact surface 510f spring by the reaction force P = _{P 4} and the elastic member 77 from the concave 76a by rolling contact of the movable member 76 of the axial load (the other of the input member 51 of the movable member 76 Force f = f ₄ ), and reaction force P = P ₄ and spring force f = f ₄ are applied to the ball bearing 56 as preload from the inner flange 51d of the other input member 51. The curvature of the rolling contact surface 510f radius R = _{R 8} is set to a dimension smaller than the curvature of the concave 76a radius _R = R ₄ of the movable member _{76 (R 4> R 8)} .

The rotation force imparting member 52 is composed of a pair of internal gears whose central axis is the axis O ₄ (fourth axis), and is disposed between the first housing element 20 and the second housing element 21. The whole is formed by a bottomless cylindrical member that opens in both directions of the axis O ₄ and constitutes a part of the housing 2. The rotation force applying member 52 meshes with the pair of input members 50 and 51, and receives the rotation force in the directions of the arrows n ₁ and n _{2 on one} input member 50 that revolves by receiving the motor rotation force of the electric motor 4. Further, rotational forces in the directions of the arrows l ₁ and l ₂ are applied to the other input member 51, respectively. 2 and 3, the axis O ₄ is drawn to coincide with the axis O ₁ .

A rotation force applying member 52, the direction of the first fitting portion 52a, and the second fitting portion 52b is the axis O ₄ fitted to the outer peripheral surface of the projection 27 to be fitted to the outer peripheral surface of the convex portion 23 Are provided at predetermined intervals.

On the inner peripheral surface of the rotation force applying member 52, the pitch meshes with the external teeth 50 c of one input member 50 and the external teeth 51 c of the other input member 51, and the axis O ₄ (axis O ₁ ) is the central axis. Circular involute tooth-shaped inner teeth 52c are provided. Number of teeth _{Z 3} of the internal teeth 52c is set to, for example, _Z 3 = 208. Number of teeth _{Z 3} of the internal teeth 52c is set to, for example, _Z 3 = 208. The reduction ratio α of the deceleration transmission mechanism 5 is calculated from α = Z ₂ / (Z ₃ −Z ₂ ).

  The output mechanism 53A includes a plurality (six in this embodiment) of output members 53, is disposed between the rear differential 3 and the electric motor 4, and is accommodated in the housing 2.

The plurality of output members 53 are arranged at equal intervals around the axis O ₁ , and are inserted through the pin insertion hole 50 b of one input member 50 and the pin insertion hole 51 b of the other input member 51, and the flange 30 c of the differential case 30. It is attached to 30f. The plurality of output members 53 receive the rotation force applied by the rotation force applying member 52 from the pair of input members 50 and 51 and output the rotation force to the differential case 30 as the rotation force. The plurality of output members 53 include a screw portion 53a for screwing the nut 64, a screw portion 53b for screwing the nut 65, shaft portions 53c and 53d adjacent to both the screw portions 53a and 53b, and both the shaft portions 53c. , 53d, and a screw member made of a stepped round shaft having a partition 53f that bisects the intermediate portion 53e in the axial direction. The nut 64 acts on the ball bearing 35 with an axial load acting on one axial side (the electric motor 4 side shown in FIG. 2), and the nut 65 acts on the other axial side (rear differential 3 side shown in FIG. 2). A load is applied to each of the ball bearings 38 as a preload.

  The plurality of output members 53 include a step surface (first step surface) 53g interposed between the shaft portion 53c on one side (rear differential 3 side) and the intermediate portion 53e, and the other side (electric motor 4 side). A step surface (second step surface) 53h is provided between the shaft portion 53d and the intermediate portion 53e.

  The contact resistance with the inner peripheral surface of the pin insertion hole 50b in one input member 50 is formed on the outer peripheral surface of the intermediate portion 53e in the plurality of output members 53 and located on the rear differential 3 side of the partition portion 53f. Needle roller bearings 55 for reduction are attached. Further, the contact resistance of the other input member 51 with the pin insertion hole 51b is reduced on the outer peripheral surface of the intermediate portion 53e in the plurality of output members 53 and located on the electric motor 4 side of the partition portion 53f. Needle roller bearings 57 are attached.

(Operation of the motor rotational force transmission device 1)
Next, the operation of the motor torque transmission device shown in the present embodiment will be described with reference to FIGS.

  In FIG. 2, when electric power is supplied to the electric motor 4 of the motor rotational force transmission device 1 to drive the electric motor 4, the motor rotational force of the electric motor 4 is applied to the deceleration transmission mechanism 5 via the motor shaft 42. The deceleration transmission mechanism 5 operates.

Therefore, the speed reduction transmission mechanism 5 performs circular motion with a eccentricity δ is the input member 50, 51 in the arrow m ₁ direction shown in FIG. 3, for example.

Accordingly, the input member 50 is the axis _{O 2} while meshing with the internal teeth 52c of the outer teeth 50c rotation force applying member 52 counterclockwise (the arrow _{n 1} direction shown in FIG. 3), also the input member 51 outer teeth 51c the rotates respectively with the internal teeth 52c while meshing with the axis _O'2 around a rotation force applying member 52 (arrow l ₁ direction shown in FIG. 3). In this case, the rotation of the input members 50 and 51 causes the inner peripheral surface of the pin insertion hole 50b to be the race 550 of the needle roller bearing 55 and the inner peripheral surface of the pin insertion hole 51b to be the needle roller bearing as shown in FIG. 57 races 570 are in contact with each other.

  For this reason, the revolution movement of the input members 50 and 51 is not transmitted to the output member 53, but only the rotation movement of the input members 50 and 51 is transmitted, and the rotation force by this rotation movement is rotated from the output member 53 to the differential case 30. Output as power.

  As a result, the rear differential 3 is operated, and the driving force based on the motor rotational force of the electric motor 4 is distributed to the rear axle shaft 106 in FIG. 1 and transmitted to the left and right rear wheels 105.

Here, in the motor torque transmission device 1, the centrifugal force F ₁ on the basis of the circular motion to one of the input member 50 with the operation and the centrifugal force F ₂ on the basis of the circular motion to the other of the input member 51 Each works.

Accordingly, movement respectively to one of the input member 50 is the direction of action of the centrifugal force F ₁ (e.g. downward in FIG. 2), also to the other input member 51 is the direction of action of the centrifugal force F ₂ (e.g. upward in FIG. 2) To do.

In this case, as shown in FIG. 4, when one of the input member 50 is under load due to the centrifugal force F ₁ generated based on the circular movement to move in that direction, a portion of the load of one of the projecting portions 50e It acts on the concave surface 70a of the movable member 70 via the rolling contact surface 500e, and acts on the concave surface 72a of the movable member 72 via the rolling contact surface 500f of the other convex portion 50f.

Therefore, will be a part of the load caused by the centrifugal force F ₁ from one of the input member 50 is concave 72a of the concave 70a and the movable member 72 of the movable member 70 receives the load applied by the centrifugal force F ₁ is the ball bearing 54 Acting on is suppressed.

Similarly, it is moving in that direction under load by the centrifugal force F ₂ which is the other of the input member 51 occurring on the basis of the circular motion, a part of the load through the rolling contact surface 510e of the one convex portion 51e It acts on the concave surface 74a of the movable member 74 and the concave surface 76a of the movable member 76 via the rolling contact surface 510f of the other convex portion 51f.

Therefore, a part of the load due to the centrifugal force F ₂ from the other input member 51 is received by the concave surface 74 a of the movable member 74 and the concave surface 76 a of the movable member 76, and the load due to this centrifugal force F _{2 is received} by the ball bearing 56. Acting on is suppressed.

  Therefore, in this embodiment, it is not necessary to use highly durable bearings 54 and 56.

On the other hand, in the ball bearing 54, the reaction force P = P ₁ due to the rolling contact of one input member 50 to the movable member 70 and the spring force f = f ₁ due to the elastic member 71 are passed through the movable member 70 and the other input. The reaction force P = P ₂ due to the rolling contact of the member 50 to the movable member 72 and the spring force f = f ₂ due to the elastic member 73 are transmitted to the one input member 50 via the movable member 72, and these reaction forces P = P ₁ and P ₂ and spring forces f = f ₁ and f ₂ are applied as preload from one input member 50.

Similarly, the ball bearing 56, the reaction force P = P ₃ and the spring force f = f ₃ by the elastic member 75 due to the rolling contact with the movable member 74 of the other of the input member 51 through the movable member 74, and the other The reaction force P = P ₄ due to the rolling contact of the input member 51 to the movable member 76 and the spring force f = f ₄ due to the elastic member 77 are transmitted to the other input member 51 through the movable member 76, respectively. = P ₁ , P ₂ and spring force f = f ₃ , f ₄ are applied as preload from the other input member 51.

  Therefore, in the present embodiment, the axial internal clearance of the ball bearings 54 and 56 is reduced, and the occurrence of rattling in the radial direction at the input members 50 and 51 can be suppressed.

In the above embodiment has described the case where the input member 50, 51 by circular motion of the arrow m ₁ direction to actuate the motor torque transmission device 1, the input member 50, 51 in the arrow m ₂ Direction Even if it makes a circular motion, the motor rotational force transmission device 1 can be operated in the same manner as in the above embodiment. In this case, the rotation of the input member 50 is performed in the direction of the arrow n ₂ , and the rotation of the input member 51 is performed in the direction of the arrow l ₂ .

[Effect of the first embodiment]
According to the first embodiment described above, the following effects can be obtained.

(1) Since the load due to the centrifugal force F ₁ from the input member 50 is restrained from acting on the ball bearing 54 and the load due to the centrifugal force F ₂ from the input member 51 is restrained from acting on the ball bearing 56, respectively. , 56 is not required to use a highly durable bearing, and the cost can be reduced.

(2) The suppression of the action of the load by the centrifugal force F ₁ on the ball bearing 54 and the action of the load by the centrifugal force F _{2 on} the ball bearing 56 can also increase the life of the ball bearings 54 and 56. .

(3) Since the axial internal clearance of the ball bearings 54 and 56 is reduced by the preload, it is possible to suppress the occurrence of rattling in the radial direction at the input members 50 and 51, and the input members 50 and 51 with respect to the motor shaft 42 can be suppressed. Axiality can be improved.

(4) Since the rotation force applying member 52 is formed of a cylindrical member that constitutes a part of the housing 2, the outer diameter of the rotation force applying member 52 is larger than that in the case where the rotation force applying member 52 is accommodated in the housing 2. Can be set to a large dimension, and the mechanical strength of the rotation force applying member 52 can be increased. In addition, the fact that the rotation force applying member 52 constitutes a part of the housing 2 can reduce the size in the radial direction of the entire apparatus and reduce the size.

(5) The first fitting portion 52a of the rotation force imparting member 52 is fitted to the outer peripheral surface of the convex portion 23, and the second fitting portion 52b is fitted to the outer peripheral surface of the convex portion 27 to perform centering. Therefore, the manufacturing process of the rotation force applying member 52 can be easily performed.

[Second Embodiment]
Next, a motor torque transmission device according to a second embodiment of the present invention will be described with reference to FIG. FIG. 6 shows a main part of the motor torque transmission device. 6, members having the same or equivalent functions as those in FIGS. 2 and 4 are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 6, in the motor torque transmission device 100 according to the second embodiment of the present invention, the rolling contact surfaces 500e and 500f of the convex portions 50e and 50f are in contact with each other around the movable members 70 and 72, respectively. Instead of the concave surfaces 70a and 72a, the surfaces are tapered surfaces 70b and 72b, and the rolling contact surfaces 510e and 510f of the convex portions 51e and 51f are in rolling contact with the peripheral surfaces of the movable members 74 and 76, instead of the concave surfaces 74a and 76a. It is characterized in that it is formed by tapered surfaces 74b and 76b, respectively.

  For this reason, the taper surface 70b of the movable member 70 on the side of the rear differential 3 (shown in FIG. 2) is cut out at a portion straddling the outer peripheral surface and the front end surface, so that the radius of curvature R is R = ∞ (infinity). It is formed with a flat surface. Further, the tapered surface 72b of the movable member 72 on the rear differential 3 side is formed by a plane having a radius of curvature R of R = ∞ (infinite) by notching a portion straddling the inner peripheral surface and the tip surface. Yes.

  The tapered surface 74b of the movable member 74 on the side of the electric motor 4 (shown in FIG. 2) is a plane in which the radius of curvature R is R = ∞ (infinite) by notching a portion straddling the outer peripheral surface and the tip surface. Is formed. Further, the tapered surface 76b of the movable member 76 on the electric motor 4 side is formed by a plane having a curvature radius R of R = ∞ (infinite) by notching a portion straddling the inner peripheral surface and the tip surface. Yes.

In such motor torque transmission apparatus 100 constructed as above, will be a part of the load caused by the centrifugal force F ₁ from one of the input member 50 is concave 72b of the concave 70b and the movable member 72 of the movable member 70 receives The load due to the centrifugal force F = F ₁ is suppressed from acting on the ball bearing 54.

Similarly, will receive a part of the load caused by the centrifugal force F = F ₂ from the other input member 51 is concave 76a of the concave 74a and the movable member 76 of the movable member 74, the load due to the centrifugal force F ₂ is the ball Acting on the bearing 56 is suppressed.

  Therefore, in this embodiment, it is not necessary to use highly durable bearings 54 and 56.

On the other hand, in the ball bearing 54, reaction forces P = P ₁ and P ₂ due to rolling contact of one input member 50 to the movable member 70 and spring forces f = f ₁ and f ₂ due to the elastic members 71 and 73 are input to one side. The preload is applied from the member 50.

Similarly, in the ball bearing 56, the reaction force P = P ₃ , f ₄ due to the rolling contact of the other input member 51 to the movable member 74 and the spring force f = f ₃ , f ₄ due to the elastic members 75, 77 are the other. It is given as a preload from the input member 51.

  Therefore, in the present embodiment, the axial internal clearance of the ball bearings 54 and 56 is reduced, and the occurrence of rattling in the radial direction at the input members 50 and 51 can be suppressed.

[Effect of the second embodiment]
According to the second embodiment described above, the following effects are obtained in addition to the effects shown in the first embodiment.

  Since each peripheral surface of the movable members 70, 72, 74, and 76 is formed by the tapered surfaces 70b, 72b, 74b, and 76b, the movable member 70 is compared with the case where the peripheral surfaces are formed by the concave surfaces 70a, 72a, 74a, and 76a. , 72, 74, and 76, the rolling contact surfaces 500e, 500f, 510e, and 510f of the convex portions 50e, 50f, 51e, and 51f are easily brought into rolling contact with each other, and the input members 50 and 51 are assembled to the motor shaft 42. Sex can be done easily.

  As mentioned above, although the deceleration mechanism of this invention and the motor rotational force transmission apparatus provided with this were demonstrated based on the said embodiment, this invention is not limited to the said embodiment, The range which does not deviate from the summary The present invention can be implemented in various modes, and for example, the following modifications are possible.

(1) In the above embodiment, equal to the distance from the distance and the axis _O'2 from the axis _{O 2} to the axis _{O 1} to the axis _{O 1,} and the axis _{O 1} around the axis _{O 2} and the axis _O'2 with one to equal the distance of the eccentric portion 42a and the other of the eccentric portion 42b is disposed on the outer periphery of the motor shaft 42, at a site away with a regular intervals (180 °) from each other in the axial line O ₁ around Although the case where the pair of input members 50 and 51 are disposed has been described, the present invention is not limited to this, and the number of input members can be changed as appropriate.

That is, when there are n (n ≧ 3) input members, in the virtual plane orthogonal to the axis of the electric motor (motor shaft), the axis of the first eccentric part, the axis of the second eccentric part,. Assuming that the axis of the nth eccentric part is sequentially arranged in one direction around the axis of the motor shaft, the distance from the axis of each eccentric part to the axis of the motor shaft is equal, and the first eccentric part, Each of the eccentric portions is formed so that the included angle formed by a line segment connecting the axes of the two eccentric portions adjacent to each other among the two eccentric portions,..., The n-th eccentric portion and the axis of the motor shaft is 360 ° / n. The n input members are disposed at the outer periphery of the motor shaft and at a part spaced about 360 ° / n around the axis O ₁ .

  For example, when there are three input members, the axis of the first eccentric part, the axis of the second eccentric part, and the axis of the third eccentric part are on the motor axis on a virtual plane orthogonal to the axis of the motor shaft. If it is sequentially arranged in one direction around the axis, the distance from the axis of each eccentric part to the axis of the motor shaft is equal, and the first eccentric part, the second eccentric part, and the third eccentric part Each eccentric part is arranged on the outer periphery of the motor shaft so that the included angle formed by the line connecting the axis line of two eccentric parts adjacent to each other and the axis line of the motor shaft is 120 °. Three input members are arranged at portions separated by an interval of 120 °.

(2) In the above embodiment, the ball bearing 35 is disposed between the inner peripheral surface of one flange 30c and the outer peripheral surface of the motor shaft 42 among the flanges 30c, 30f as the constituent elements of the differential case 30, and the other flange 30f. In the above description, the ball bearings 38 are interposed between the inner circumferential surface of the motor shaft 42 and the outer circumferential surface of the motor shaft 42. However, the present invention is not limited to this, and as shown in FIG. The ball bearing 35 may be interposed only between the surface and the outer peripheral surface of the motor shaft 42. In this case, the flange 30f is connected by a plurality of output members 53 with the flange end face opposed to the flange 30c on the axis (axis O ₁ ) of the motor shaft 42, and is entirely formed of an annular member. The flange 30f is provided with an accommodation hole 300f for accommodating a part of the annular member 25.

(3) Although the case where the contact target is the differential case 30 has been described in the above embodiment, the present invention is not limited to this, and a rotation force applying member may be the contact target.

(4) In the above embodiment, the concave surfaces 70a, 72a, 74a, and 76a with which the rolling contact surfaces 500e, 500f, 510e, and 510f of the convex portions 50e, 50f, 51e, and 51f are in contact are movable members 70, 72, 74, However, the present invention is not limited to this, and may be provided directly on the output target or the rotation force applying member as the contact target.

(5) In the above embodiment, the case where the peripheral surfaces of the movable members 70, 72, 74, and 76 are formed by the concave surfaces 70a, 72, 74a, and 76a has been described. However, the present invention is not limited to this, The peripheral surface of the movable member may be formed as a convex surface. In this case, the peripheral surface of each convex part of the input member with which the convex surface of the movable member comes into rolling contact is formed as a concave surface.

(6) In the above embodiment, the case where the present invention is applied to the four-wheel drive vehicle 101 using both the engine 102 and the electric motor 4 as the drive source has been described. However, the present invention is not limited to this, and only the electric motor is used as the drive source. The present invention can also be applied to an electric vehicle that is a four-wheel drive vehicle or a two-wheel drive vehicle. The present invention can also be applied to a four-wheel drive vehicle having an engine, a first drive shaft by an electric motor, and a second drive shaft by an electric motor, as in the above embodiment.

(7) In the above embodiment, between the outer peripheral surface of the eccentric portion 42a of the motor shaft 42 and the inner peripheral surface of the center hole 50a in one input member 50, and the outer peripheral surface of the eccentric portion 42b of the motor shaft 42 Although the case where the ball bearings 54 and 56 which are deep groove ball bearings are respectively interposed between the inner peripheral surface of the center hole 51a in the other input member 51 has been described, the present invention is not limited thereto, and the deep groove ball bearing is not limited thereto. Alternatively, ball bearings or roller bearings other than deep groove ball bearings may be used. Examples of such ball bearings and roller bearings include angular contact ball bearings, needle roller bearings, rod roller bearings, cylindrical roller bearings, tapered roller bearings, and self-aligning roller bearings.

(8) In the above embodiment, the inner rings 540 and 560 of the ball bearings 54 and 56 are respectively attached to the outer peripheral surfaces of the eccentric parts 42a and 42b of the motor shaft 42 by interference fit, and the outer rings 541 and 541 of the ball bearings 54 and 56 are attached. Although the case where 561 is attached to the inner peripheral surfaces of the center holes 50a and 51a in the input members 50 and 51 by clearance fitting, respectively, the present invention is not limited to this, and any inner ring and outer ring It may be an interference fit, a clearance fit, or an interference fit with respect to the peripheral surface to be attached.

DESCRIPTION OF SYMBOLS 1 ... Motor rotational force transmission apparatus, 2 ... Housing, 20 ... 1st housing element, 20a ... Shaft penetration hole, 20b ... Inner flange, 20c ... Notch, 21 ... 2nd housing element, 21a ... Inner flange, 22 3rd housing element, 22a ... Shaft insertion hole, 22b ... Cylindrical part, 22c ... Step surface, 23 ... Convex part, 24 ... Seal member, 25 ... Ring member, 27 ... Convex part, 28 ... Seal member, 3 ... rear differential, 30 ... differential case, 30a ... accommodation space, 30b ... shaft insertion hole, 30c ... flange, 300c ... pin insertion hole, 301c, 302c ... concave groove, 30d ... step surface, 30e ... concave hole, 300e ... step surface , 30f ... flange, 300f ... accommodation hole, 301f ... pin insertion hole, 302f ... convex part, 303f, 304f ... concave groove, 31 ... Nonion gear shaft, 32 ... pinion gear, 33 ... side gear, 34 ... ball bearing, 340 ... inner ring, 35 ... ball bearing, 350 ... inner ring, 351 ... outer ring, 352 ... rolling element, 37 ... spacer, 38 ... ball bearing, 381 ... Outer ring, 4 ... Electric motor, 40 ... Stator, 41 ... Rotor, 42 ... Motor shaft, 42a, 42b ... Eccentric part, 42c ... Stepped surface, 42e ... Stepped surface, 42g ... Stepped surface, 43 ... Mounting bolt, 44 ... Ball Bearing, 45 ... Sleeve, 46 ... Ball bearing, 460 ... Inner ring, 461 ... Outer ring, 47 ... Resolver, 470 ... Stator, 471 ... Rotor, 5 ... Deceleration transmission mechanism, 50, 51 ... Input member, 50a, 51a ... Center hole , 50b, 51b ... pin insertion hole, 50c, 51c ... external teeth, 50d, 51d ... inner flange, 50e, 50f ... convex, 500e, 500f ... rolling contact surface, 51 , 51f ... convex portion, 510e, 510f ... rolling contact surface, 52 ... autorotation force applying member, 52a ... first fitting portion, 52b ... second fitting portion, 53A ... output mechanism, 53 ... output member, 53a , 53b ... Screw part, 53c, 53d ... Shaft part, 53e ... Intermediate part, 53f ... Partition part, 53g, 53h ... Stepped surface, 54 ... Ball bearing, 540, 541 ... Race (inner ring 540, outer ring 541), 55 ... Needle roller bearing, 550 ... race, 56 ... ball bearing, 560, 561 ... race (inner ring 560, outer ring 561), 57 ... needle roller bearing, 570 race, 63 ... sleeve, 64, 65 ... nut, 70 ... movable 70a ... concave surface, 71 ... elastic member, 72 ... movable member, 72a ... concave surface, 73 ... elastic member, 74 ... movable member, 74a ... concave surface, 75 ... elastic member, 76 ... movable member, 76a ... concave surface, 77 ... Elastic part Material: 100 ... Motor rotational force transmission device, 101 ... Four-wheel drive vehicle, 102 ... Engine, 103 ... Transaxle, 104 ... Front wheel, 105 ... Rear wheel, 106 ... Rear axle shaft, 107 ... Front axle shaft, a, b, c, d ... rolling contact point, L, O ₁ , O ₂ , O ' ₂ , O ₃ , O ₄ , O ₅ ... axis, A ₁ , A ₂ , A ₃ , A ₄ ... locus, F ... centrifugal force, P: reaction force, R: radius of curvature, f: spring force, δ: eccentricity

Claims (8)

A rotating shaft having an eccentric portion;
An input member composed of an external gear having a plurality of through-holes that are rotatably supported via a bearing on the outer peripheral surface of the eccentric portion of the rotating shaft and are arranged in parallel at equal intervals around the axis;
A rotation force applying member that is engaged with the input member and includes an internal gear having a number of teeth larger than the number of teeth of the external gear;
Receiving a rotation force applied to the input member by the rotation force application member, outputting the output force as a rotational force, and a plurality of output members respectively inserted through the plurality of through holes,
The input member has an annular convex portion protruding in the axial direction, and the peripheral surface of the convex portion is in rolling contact with the contact target side with the output target or the rotation force applying member as a contact target. A speed reduction mechanism formed by rolling contact surfaces.   2. The speed reduction mechanism according to claim 1, wherein the input member includes a curved surface on which the rolling contact surface receives an axial load from the contact target side and is applied as a preload to the bearing.   2. The input member is disposed at a position where an annular movable member is interposed between the rolling contact surface and the contact target and receives an elastic force from an elastic member in an axial direction from the movable member side. Or the deceleration mechanism of 2.   The speed reduction mechanism according to claim 3, wherein the input member has the rolling contact surface as a convex surface, and the rolling contact surface is brought into rolling contact with a tapered surface or a concave surface provided on the movable member.   The speed reduction mechanism according to any one of claims 1 to 4, wherein the rolling contact surface of the input member is disposed as an inner peripheral surface of the convex portion on a radially outer side of the plurality of output members.   The speed reduction mechanism according to any one of claims 1 to 5, wherein the rolling contact surface of the input member is disposed as an outer peripheral surface of the convex portion on a radially inner side of the plurality of output members.   The plurality of output members are each formed by a connecting member that inserts a pair of flanges as components of the output object that face each other via the input member and connects the pair of flanges. Item 7. The speed reduction mechanism according to any one of Items 1 to 6. An electric motor for generating motor rotational force;
A motor rotational force transmission device comprising a speed reduction mechanism that decelerates the motor rotational force of the electric motor and outputs a driving force;
The said reduction mechanism is a reduction mechanism of any one of Claim 1 thru | or 7. A motor rotational force transmission apparatus.

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