JP2017141910A - Transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form second and third transmission grooves in a second transmission member while preventing a strength of the second transmission member from being lacked even without setting the tabular second transmission member to be specially thick in a transmission device comprising: a first transmission member defining a first axis as the center axis; an eccentric rotation member in which a main shaft part rotatable around the first axis and an eccentric shaft part defining a second axis as the center axis are integrally connected; the tabular second transmission member which is supported in a freely rotatable manner by the eccentric shaft part; the third transmission member which faces the second transmission member while defining the first axis as the center axis; a first transmission mechanism between the first and second transmission members; and a second transmission mechanism between the second and third transmission members.SOLUTION: On a side face 8f of a second transmission member 8 at one side in an axial direction, a second transmission groove 22 of a first transmission mechanism T1 and a third transmission groove 24 of a second transmission mechanism T2 which is disposed to be surrounded by the second transmission groove 22, are provided together.SELECTED DRAWING: Figure 1

Description

  The present invention is centered on a transmission device, particularly a first transmission member arranged so that the first axis is a central axis, a main shaft portion rotatable around the first axis, and a second axis eccentric from the first axis. An eccentric rotating member integrally connected to an eccentric shaft portion serving as an axis, a second transmission member that is rotatably supported by the eccentric shaft portion and faces the first transmission member, and the first axis as a central axis A third transmission member disposed opposite to the second transmission member, a first transmission mechanism capable of transmitting torque while shifting between the first and second transmission members, and between the second and third transmission members. The present invention relates to a transmission device including a second transmission mechanism capable of transmitting torque while shifting.

  The transmission device is conventionally known as disclosed in, for example, Patent Document 1. In this device, the first speed change mechanism is located on a surface of the first transmission member facing the second transmission member, and the first axis is arranged. A second corrugated annular first transmission groove and a second transmission member on a surface facing the first transmission member, the second transmission member being a corrugated annular centered on the second axis and having a wave number different from the first transmission groove. A plurality of transmission grooves and a plurality of intersections of the first and second transmission grooves, and a plurality of transmission gears involved in the transmission between the first and second transmission members while rolling the first and second transmission grooves. A third rolling element having a first rolling element, the second speed change mechanism being located on a surface of the second transmission member facing the third transmission member and having a wavy annular shape centering on the second axis; The transmission member is on the surface facing the second transmission member and has a wave shape with the first axis as the center, and the wave number is different from that of the third transmission groove. 4 transmission grooves and a plurality of intersections of the third and fourth transmission grooves, and a plurality of transmissions for performing transmission transmission between the second and third transmission members while rolling the third and fourth transmission grooves And a second rolling element.

  In this transmission device, for example, the first to third transmission members are configured in a plate shape and arranged so that the three members overlap in the axial direction, thereby reducing the axial width of the device, There is an advantage that the flatness in the axial direction can be reduced.

Japanese Patent No. 4814351

  However, in the transmission device of Patent Document 1, a second transmission groove is formed on one side surface in the axial direction of the second transmission member, and a third transmission groove is formed on the other side surface, and these second and third transmission grooves are They are arranged so as to overlap each other when viewed on the projection plane orthogonal to the second axis. Therefore, the thickness of the second transmission member between the bottoms of the second and third transmission grooves inevitably decreases, which is disadvantageous in increasing the strength of the second transmission member.

  That is, during transmission of the transmission, each transmission groove in the first and second transmission mechanisms receives a load in the expansion direction from the corresponding rolling element, and stress concentration occurs at the bottom of the groove. At this time, if the thickness of the second transmission member between the two grooves is reduced due to the formation of the second and third transmission grooves, there is a problem that the portion is likely to be deformed and damaged due to the stress concentration. is there.

  Therefore, in the conventional device, in order to avoid the above problem, the thickness of the entire second transmission member is set to be thick in anticipation of the reduction in the thickness between the two grooves, and this increases the weight of the second transmission member and thus the transmission device. Not only does this increase the weight, it also causes a slight increase in the axial width of the transmission.

  The present invention has been made in view of such circumstances, and the second transmission member can be provided with the second transmission member without causing a lack of strength thereof without setting the thickness of the plate-like second transmission member to be particularly thick. An object of the present invention is to provide a transmission device capable of forming the second and third transmission grooves.

  In order to achieve the above object, the present invention provides a first transmission member arranged so that the first axis is a central axis, a main shaft portion rotatable around the first axis, and a first shaft eccentric from the first axis. An eccentric rotating member integrally connected with an eccentric shaft portion having two axes as a central axis, and a plate-like second transmission member that is rotatably supported by the eccentric shaft portion and faces the first transmission member; A first transmission mechanism that is arranged with the first axis as a central axis and that faces the second transmission member, and a first transmission mechanism capable of transmitting torque while shifting between the first and second transmission members. And a second transmission mechanism capable of transmitting torque while shifting between the second and third transmission members, wherein the first transmission mechanism is a surface of the first transmission member facing the second transmission member. The first transmission groove having an annular shape centered on the first axis and the first axis A plurality of first and second transmission grooves, a second transmission groove on the surface of the transmission member facing the first transmission member and having a wave shape centered on the second axis and having a wave number different from that of the first transmission groove; And a plurality of first rolling elements that perform speed change transmission between the first and second transmission members while rolling in the first and second transmission grooves. The mechanism is a wave-shaped third transmission groove on the surface of the second transmission member facing the third transmission member and centering on the second axis, and the second transmission member of the third transmission member A fourth annular groove having a wave shape centered on the first axis and having a wave number different from that of the third transmission groove, and a plurality of intersections of the third and fourth transmission grooves. A plurality of second rolling elements for performing transmission transmission between the second and third transmission members while rolling the third and fourth transmission grooves; The second transmission member includes a second transmission groove and a third transmission groove arranged to be surrounded by the second transmission groove on a side surface on one side in the axial direction of the second transmission member. The first feature is that they are provided together.

  According to the present invention, in addition to the first feature, the first transmission member is formed in an annular shape, and the third transmission member is disposed so that at least a part of the third transmission member is surrounded by the first transmission member. This is the second feature.

  In addition to the first or second feature, the third feature of the present invention is that the third transmission groove is set to have a smaller wave number than the second transmission groove.

  In addition to any one of the first to third features, the present invention further includes a casing that houses the first to third transmission members and supports the first transmission member so as not to be relatively rotatable. A fourth feature is that any one of a pair of shafts arranged on the axis is connected to the main shaft portion, and any one of the other shafts is connected to the third transmission member.

  According to the first feature of the present invention, the second transmission member has a second transmission groove on a side surface on one side in the axial direction, and a third transmission groove disposed so as to be surrounded by the second transmission groove. Since both are provided, the thickness reduction of the 2nd transmission member in each groove bottom of the 2nd and 3rd transmission groove can be suppressed to the minimum. Thereby, even if the thickness of the plate-like second transmission member is not set to be particularly thick, the second transmission member can accurately form the second and third transmission grooves without causing insufficient strength. In addition, it is possible to contribute to the weight reduction of the second transmission member, and thus to the weight reduction of the transmission device, and to contribute to the miniaturization of the transmission device by suppressing the increase in the axial width of the transmission device. In addition, by providing the second and third transmission grooves only on one side surface of the second transmission member, both the transmission grooves can be efficiently molded from the one side surface to the second transmission member at once. Therefore, it can contribute to the improvement of productivity.

  According to the second feature of the present invention, the first transmission member is formed in an annular shape, and the third transmission member is arranged so that at least a part of the third transmission member is surrounded by the first transmission member. The space on the inner peripheral side of the first transmission member forming the third transmission member can be used as the installation space for the third transmission member, thereby further reducing the axial width of the transmission device, and further reducing the transmission in the axial direction. A device is obtained.

  According to the third feature of the present invention, since the third transmission groove is set to have a smaller wave number than the second transmission groove, the third transmission groove is on the radially inner side of the second transmission groove. Even if the diameter of the third transmission groove is relatively small, the third transmission groove can be accurately formed without particularly increasing the curvature of the groove because the wave number of the third transmission groove is relatively small.

  According to a fourth aspect of the present invention, the apparatus includes a casing that houses the first to third transmission members and supports the first transmission member so that the first transmission member cannot be rotated relative to the first axis. Since either one is connected to the main shaft portion of the eccentric rotating member and the other is connected to the third transmission member, the transmission device can be compactly arranged in the axial direction between a pair of coaxially arranged shafts. It can be configured as a speed reducer or speed increaser.

Whole longitudinal cross-sectional view of the transmission device (reduction gear) which concerns on 1st Embodiment 2-2 sectional view of FIG. Overall longitudinal sectional view of a transmission device (differential device) according to a second embodiment Sectional view taken along line 4-4 in FIG.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  First, a first embodiment of the present invention shown in FIGS. 1 and 2 will be described. In FIG. 1, a vehicle speed reducer R as a transmission device decelerates the rotation of the first transmission shaft S1 via the first and second transmission mechanisms T1 and T2 and transmits it to the second transmission shaft S2. A power source (not shown) is connected to the first transmission shaft S1 as the input shaft directly or via a transmission mechanism. Further, various operating devices (for example, wheels) that are driven to decelerate by the power from the power source are connected to the second transmission shaft S2 as the output shaft directly or via a transmission mechanism.

  The reduction gear R includes a hollow casing C fixedly supported by a support body (not shown) (for example, a vehicle body frame), and first, second, and third transmission members 5 that are housed in the casing C and have an annular shape. 8, 9, the first rotating member capable of transmitting torque while shifting between the eccentric rotating member 6 housed in the casing C and surrounded by the second transmission member 8, and the first and second transmission members 5, 8. The main component is a mechanism T1 and a second transmission mechanism T2 capable of transmitting torque while shifting between the second and third transmission members 8 and 9.

  The casing C has a hollow split structure in which the first and second casing halves C1 and C2 are detachably fastened. First and second bearing boss portions 41 and 42 extending integrally outward in the axial direction are connected to the inner peripheral portions of the casing halves C1 and C2, respectively. In the portions 41 and 42, the inner ends of the first and second transmission shafts S1 and S2 rotate around the first axis X1 via first and second bearings B1 and B2 and B2 '(for example, ball bearings), respectively. Supported as possible.

  The first transmission member 5 is formed in a plate shape with the first axis X1 as a central axis, and is connected to one side wall of the casing C (that is, the first casing half C1) in a relatively non-rotatable manner. In the present embodiment, the first transmission member 5 is fixed to the casing C by fixing means (for example, welding, caulking, etc.), but the first transmission member 5 may be formed integrally with the casing C, or spline-fitted. May be combined.

  The eccentric rotating member 6 integrally includes a main shaft portion 6j having a first axis line X1 as a central axis, and an eccentric shaft portion 6e having a second axis line X2 eccentric from the first axis X1 by a predetermined eccentric amount e as a central axis line. The first transmission shaft S1 is coaxially connected to the main shaft portion 6j (formed integrally in the present embodiment). Note that the eccentric rotating member 6 and the first transmission shaft S1 may be formed separately and connected so as to rotate together (for example, spline fitting).

  The second transmission member 8 is formed in a plate shape, and is supported on the eccentric shaft portion 6e so as to be rotatable around the second axis X2 via a third bearing B3 (for example, a ball bearing). One side surface 8 f of the second transmission member 8 is opposed to the inner surface of the first transmission member 5 in the axial direction.

  The third transmission member 9 is formed in a plate shape with the first axis line X1 as the central axis, and is arranged concentrically on the radially inner side of the first transmission member 5. With this arrangement, at least a part (substantially all in the present embodiment) of the third transmission member 9 is surrounded by the first transmission member 5. The third transmission member 9 is coaxially connected to the second transmission shaft S2 (integrally formed in the present embodiment), and the inner side surface of the third transmission member 9 is also the above-mentioned second transmission member 8. Opposite the one side 8f. Alternatively, the third transmission member 9 and the second transmission shaft S2 may be formed separately and connected so as to rotate together (for example, spline fitting).

  Thus, the second transmission member 8 rotates about the second axis X2 with respect to the eccentric shaft portion 6e as the eccentric rotation member 6 (first transmission shaft S1) rotates about the first axis X1, while rotating about the second axis X2. Revolve around the first axis X1 with respect to one transmission shaft S1.

  Further, in the present embodiment, during the torque transmission by the first and second transmission mechanisms T1, T2, the second transmission member 8 is separated from the first and third transmission members 5, 8 (leftward in FIG. 1). Although the thrust load acts, the thrust load can be received by the first transmission shaft S1 via the third bearing B3. Thereby, rotation resistance can be reduced compared with the case where the back surface of the 2nd transmission member 8 is made to slide-contact with the casing C (1st casing half body C1), and a thrust load is received.

  Next, the first and second transmission mechanisms T1 and T2 will be described in order.

  On the inner surface of the first transmission member 5 facing the second transmission member 8, a wavy annular first transmission groove 21 centering on the first axis X <b> 1 is formed, and the first transmission groove 21 is illustrated in the illustrated example. Then, it extends in the circumferential direction along a hypotrochoid curve having a virtual circle centered on the first axis X1 as a base circle. On the other hand, a portion of one side surface 8f of the second transmission member 8 that faces the first transmission member 5 (that is, a side surface portion near the outer periphery) has a corrugated annular second transmission groove 22 centered on the second axis X2. It is formed. In the illustrated example, the second transmission groove 22 extends in the circumferential direction along an epitrochoid curve having a virtual circle centered on the second axis X2 as a base circle, and is different from the wave number Z1 of the first transmission groove 21. Crosses the first transmission groove 21 at a plurality of locations with a wave number Z2 (for example, small). A plurality of first balls 23 as first rolling elements are interposed at intersections (that is, overlapping portions) of the first transmission groove 21 and the second transmission groove 22, and each of the first balls 23 is a first one. And the inner surface of the 2nd transmission grooves 21 and 22 can roll freely.

  Between the opposing surfaces of the first transmission member 5 and the second transmission member 8, an annular and flat first holding member H1 is interposed. The first holding member H1 can maintain the engaged state of the plurality of first balls 23 in both the transmission grooves 21 and 22 at the intersections of the first and second transmission grooves 21 and 22. A plurality of circular holding holes 31 are provided to hold the plurality of first balls 23 in a freely rotating manner while keeping their mutual intervals constant.

  In addition, a portion of the one side surface 8f of the second transmission member 8 that faces the third transmission member 9 (that is, a side surface portion closer to the inner periphery) has a third annular transmission groove having a wave shape centered on the second axis X2. 24 is formed, and the third transmission groove 24 extends in the circumferential direction along an epitrochoid curve having a virtual circle centered on the second axis X2 in the illustrated example. On the other hand, on the inner surface of the third transmission member 9 facing the second transmission member 8, a wavy annular fourth transmission groove 25 centering on the first axis X <b> 1 is formed. In the illustrated example, the fourth transmission groove 25 extends in the circumferential direction along a hypotrochoid curve having a virtual circle centered on the first axis X1 as a base circle, and is different from the wave number Z3 of the third transmission groove 24. It intersects with the third transmission groove 24 at a plurality of locations with a wave number Z4 (for example, less). A plurality of second balls 26 as second rolling elements are interposed at the intersecting portion (overlapping portion) of the third transmission groove 24 and the fourth transmission groove 25, and each second ball 26 has a third and a third one. 4 The inner surfaces of the transmission grooves 24 and 25 can roll freely.

  Between the opposing surfaces of the third transmission member 9 and the second transmission member 8, an annular and flat second holding member H2 surrounded by the first holding member H1 is interposed. The second holding member H2 can maintain the engagement state of the plurality of second balls 26 to the transmission grooves 24 and 25 at the intersections of the third and fourth transmission grooves 24 and 25. The plurality of second balls 26 are provided with a plurality of circular holding holes 32 for holding the second balls 26...

  By the way, the second and third transmission grooves 22 and 24 that are formed on the one side surface 8f in the axial direction of the second transmission member 8 and have a corrugated ring shape are surrounded by the second transmission groove 22. Arrangement is formed. Moreover, in the present embodiment, the wave number Z3 of the third transmission groove 24 on the radially inner side is set to be smaller than the wave number Z2 of the second transmission groove 22 on the radially outer side.

  Thus, the first transmission groove 21, the second transmission groove 22, and the first ball 23 constitute a first transmission mechanism T1 that cooperates with each other to perform a first-stage speed change (deceleration), and a third transmission. The groove 24, the fourth transmission groove 25, and the second ball 26 constitute a second transmission mechanism T2 that cooperates with each other to perform a second-stage speed change (deceleration).

  An annular seal member 43 is interposed between the first bearing boss 41 of the casing C and the first transmission shaft S1 on the outer side of the first bearing B1, and the second bearing boss 42 and An annular seal member 44 is interposed between the second transmission shafts S2 between the second bearings B2 and B2 ′. These sealing members 43 and 44 shield the speed reduction mechanism in the casing C from the outside.

  Next, the operation of the first embodiment will be described.

  When the first transmission shaft S1 (input shaft) is rotationally driven by power from a power source (not shown), the eccentric shaft portion 6e of the eccentric rotation member 6 integrated therewith revolves around the first axis X1, and accordingly The second transmission member 8 on the eccentric shaft portion 6e also revolves around the first axis X1. According to this revolution, both the grooves 21, between the first transmission groove 21 of the first transmission member 5 fixed to the casing C and restricted in rotation and the second transmission groove 22 of the second transmission member 8, Each first ball 23 engaged at the intersection of 22 rolls on both grooves 21 and 22, whereby the second transmission member 8 rotates around the second axis X <b> 2 on the eccentric shaft portion 6 e.

  According to the rotation and revolution of the second transmission member 8, the intersection of the grooves 24 and 25 between the third and fourth transmission grooves 24 and 25 on the second and third transmission members 8 and 9. As the second balls 26 that engage with each other roll on the grooves 24 and 25, the third transmission member 9 is driven to rotate about the first axis X1. The rotation driving force is transmitted to the second transmission shaft S2 (output shaft) integral with the third transmission member 9.

  Thus, the rotation of the first transmission shaft S1 driven by the power from the power source is decelerated and transmitted to the second transmission shaft S2 through the first and second speed change mechanisms T1 and T2, and is transmitted to the second transmission shaft S2. Accordingly, it is possible to drive the operating equipment connected thereto at a reduced speed.

In the rolling ball type speed reducer R as in this embodiment, the wave number of the first transmission groove 21 is Z1, the wave number of the second transmission groove 22 is Z2, the wave number of the third transmission groove 24 is Z3, When the wave number of the transmission groove 25 is Z4, the reduction ratio ε between the first transmission shaft S1 (input shaft) and the second transmission shaft S2 (output shaft) is
ε = 1 − {(Z1 × Z3) / (Z2 × Z4)}
Represented as:

  In the rolling ball type reduction gear R, torque transmission between the first transmission member 5 and the second transmission member 8 is performed via the first transmission groove 21, the plurality of first balls 23, and the second transmission groove 22. Further, torque transmission between the second transmission member 8 and the third transmission member 9 is performed via the third transmission groove 24, the plurality of second balls 26, and the fourth transmission groove 25. Thereby, between each of the 1st transmission member 5 and the 2nd transmission member 8, and the 2nd transmission member 8 and the 3rd transmission member 9, torque transmission is carried out to a plurality of places where the 1st and 2nd balls 23 and 26 exist. Since it is performed in a distributed manner, the strength and weight of each transmission element such as the first to third transmission members 5, 8, 9 and the first and second balls 23, 26 can be increased. Moreover, according to the transmission structure of the present embodiment, it is possible to provide a transmission (reduction gear R) that is easily flattened in the axial direction by making the first to third transmission members 5, 8, 9 each plate-like. It becomes.

  Further, in the present embodiment, the second and third transmission grooves 22 and 24 having a wavy shape do not intersect each other only on one axial side surface 8f (right side surface in FIG. 1) of the second transmission member 8 (that is, the first transmission member 8). The second transmission groove 22 is arranged and formed so that the third transmission groove 24 is surrounded. Therefore, since the thickness reduction of the 2nd transmission member 8 between the groove bottoms of the 2nd and 3rd transmission grooves 22 and 24 is suppressed to the minimum, the thickness of the 2nd transmission member 8 which makes plate shape is set to special thickness. Even without this, the second transmission member 8 can accurately form the second and third transmission grooves 22 and 24 without causing insufficient strength. Thereby, the weight reduction of the 2nd transmission member 8 and the weight reduction of a transmission device (reduction gear R) are achieved, and also the increase in the axial direction width of a transmission device (reduction gear R) is suppressed effectively, Flatness reduction is achieved.

  In addition, in the present embodiment, the third transmission groove 24 is disposed in the radial direction of the second transmission groove 22 because the second transmission groove 22 surrounds the third transmission groove 24 having a relatively small wave number Z3. Even if the third transmission groove 24 has a relatively small diameter by being on the side, the third transmission groove 24 can be accurately formed by reducing the wave number Z3 of the third transmission groove 24 without particularly increasing its curvature. .

  In addition, according to the present embodiment, the second and third transmission grooves 22 and 24 are provided only on the side surface 8f on one side of the second transmission member 8, thereby forming the transmission grooves 22 and 24 (for example, forging, Molding such as sintering or casting) or processing (for example, cutting) can be efficiently performed on the second transmission member 8 from one side face at a time, thereby improving productivity.

  Further, the third transmission member 9 of the present embodiment is arranged so that at least a part (substantially all in this embodiment) of the third transmission member 9 is surrounded by the annular first transmission member 5. The space on the inner peripheral side can be used as the installation space for the third transmission member 9. Thereby, since the axial direction width | variety of a transmission device (reduction gear R) can further be shortened, a more compact transmission device is obtained by an axial direction.

  Next, a second embodiment will be described with reference to FIGS. In the previous embodiment, the rolling ball type reduction gear R was exemplified as the transmission device, but the transmission device of the second embodiment is exemplified as the rolling ball type vehicle differential device D.

  The differential device D is housed in a transmission case 100 together with a transmission (not shown), and a pair of drive axles arranged on the first axis X1 to rotate the ring gear Cg linked to a power source such as an engine via the transmission. Distribution is performed while allowing differential rotation between the shafts S1 and S2 with respect to S1 and S2 (that is, the first and second transmission shafts). The drive axles S1, S2 and the transmission case 100 are sealed with a seal member 101.

  The differential device D includes a casing C that is rotatably supported by the mission case 100 around the first axis X1, and a differential mechanism Dm described later that is housed in the casing C. The casing C functions as a differential case, and a cylindrical casing main body Cm having a ring gear Cg made of a helical gear on the outer peripheral portion, and outer peripheral end portions are integrally joined to both axial end portions of the casing main body Cm. A pair of left and right side walls Ca and Cb.

  Both side walls Ca and Cb integrally have cylindrical boss-like first and second bearings B1 and B2 extending outward in the axial direction at the respective inner peripheral ends. The outer peripheral portions of the first and second bearings B1 and B2 are supported by the transmission case 100 so as to be rotatable around the first axis X1 via an outer bearing 102 (for example, a ball bearing). The first and second drive axles S1 and S2 are rotatably fitted and supported on the inner peripheral surfaces (that is, bearing surfaces) of the first and second bearings B1 and B2, respectively.

  Next, the structure of the differential mechanism Dm will be described. The differential mechanism Dm includes first, second, and third transmission members 5, 8, and 9 each having an annular shape that is accommodated in the casing C, and the first and second transmission members 5 that are accommodated in the casing C. , 8, between the first and second transmission members 8, 9, the first transmission mechanism T 1 capable of transmitting torque while shifting between the first and second transmission members 5, 8. The second transmission mechanism T2 capable of transmitting torque while shifting is a main component.

  The first transmission member 5 has the first axis X1 as a central axis, and is coaxially connected to one side wall Cb of the casing C (formed integrally in the present embodiment). The first transmission member 5 may be configured separately from the casing C, and may be fixed (for example, welded) to the casing C or may be spline fitted.

  The eccentric rotating member 6 integrally includes a main shaft portion 6j having a first axis line X1 as a central axis, and an eccentric shaft portion 6e having a second axis line X2 as a central axis. The main shaft portion 6j includes a first shaft portion 6j. The inner end portion of the first drive axle S1 serving as the transmission shaft is connected coaxially (in this embodiment, spline fitting 111). A second transmission member 8 is supported on the eccentric shaft portion 6e via a third bearing B3 (for example, a ball bearing) so as to be rotatable about the second axis X2, and one axial side surface 8f of the second transmission member 8 is supported. Is opposed to the inner surface of the first transmission member 5.

  The third transmission member 9 is coaxially connected to the second drive axle S2 that rotates around the first axis X1 (in this embodiment, the spline fitting 112), and around the first axis X1 together with the second drive axle S2. Rotate to. Further, the inner side surface of the third transmission member 9 is opposed to one axial side surface 8 f of the second transmission member 8.

  In the second embodiment, the second transmission groove 22 disposed on the outer peripheral side of the second transmission member 8 is a groove extending in the circumferential direction along the epitrochoid curve as in the first embodiment. 2 Unlike the first embodiment, the third transmission groove 24 disposed on the inner peripheral side of the transmission member 8 is a groove extending in the circumferential direction along the hypotrochoid curve. And the 4th transmission groove 25 of 2nd Embodiment is a groove | channel extended in the circumferential direction along an epitrochoid curve.

  Thus, also in the second embodiment, the second transmission member 8 has the second axis X2 with respect to the eccentric shaft portion 6e as the eccentric rotation member 6 (first drive axle S1) rotates about the first axis X1. Revolving around the first axis X1 relative to the first drive axle S1 while rotating around.

  The structure of the first and second speed change mechanisms T1 and T2 of the second embodiment is basically the same as the structure of the first and second speed change mechanisms T1 and T2 of the first embodiment. The description of the mechanism is omitted only by attaching the same reference numerals. However, in the second embodiment, when the first and second speed change mechanisms T1 and T2 rotate the casing C with the eccentric rotating member 6 (first driving axle S1) fixed, the first transmission member 5 is used. The third transmission member 9 is configured to be driven with a double speed increasing ratio.

  Therefore, in the second embodiment, the wave number of the first transmission groove 21 is Z1, the wave number of the second transmission groove 22 is Z2, the wave number of the third transmission groove 24 is Z3, and the wave number of the fourth transmission groove 25 is Z4. Then, the first to fourth transmission grooves 21, 22, 24, 25 are formed so that the following formula is established.

(Z1 / Z2) × (Z3 / Z4) = 2
Desirably, for example, Z1 = 8, Z2 = 6, Z3 = 6, and Z4 = 4.

  In this case, the eight-wave first transmission groove 21 and the six-wave second transmission groove 22 intersect at seven locations, and seven first balls 23 are interposed at the seven intersection portions (overlapping portions). The 6-wave third transmission groove 24 and the 4-wave fourth transmission groove 25 intersect at five locations, and five second balls 26 are interposed at the five intersection portions (overlapping portions). Is done.

  In the above case, for example, in a state where the eccentric rotating member 6 (and hence the eccentric shaft portion 6e) is fixed by fixing the first drive axle S1, the ring gear Cg is driven by the power from the engine, and the casing C (and therefore the first shaft 1). When the transmission member 5) is rotated around the first axis X1, the first transmission groove 21 of the first transmission member 5 and the second transmission groove 22 of the six transmission waves of the second transmission member 8 become the first ball 23. Therefore, the first transmission member 5 drives the second transmission member 8 with a speed increasing ratio of 8/6. Then, according to the rotation of the second transmission member 8, the six-wave third transmission groove 24 of the second transmission member 8 passes the four-wave fourth transmission groove 25 of the third transmission member 9 via the second ball 26. Therefore, the second transmission member 8 drives the third transmission member 9 with a speed increasing ratio of 6/4.

After all, the first transmission member 5 is
(Z1 / Z2) × (Z3 / Z4) = (8/6) × (6/4) = 2
The third transmission member 9 is driven with the speed increasing ratio.

  On the other hand, when the differential case (and hence the first transmission member 5) is rotated in a state where the third transmission member 9 is fixed by fixing the second drive axle S2, the rotational drive force of the first transmission member 5 and the second The second transmission member 8 rotates with respect to the eccentric shaft portion 6e (second axis X2) of the eccentric rotating member 6 by the driving reaction force of the transmission member 8 against the stationary third transmission member 9, and the first axis X1. Revolving around, the eccentric shaft portion 6e is driven around the first axis X1. As a result, the first transmission member 5 drives the eccentric rotating member 6 with a double speed increasing ratio.

  Thus, when the loads of the eccentric rotating member 6 and the third transmission member 9 are balanced with each other or change with each other, the amount of rotation and the amount of revolution of the second transmission member 8 change steplessly, and the eccentric rotation The average value of the rotational speeds of the member 6 and the third transmission member 9 is equal to the rotational speed of the first transmission member 5. Thus, the rotation of the first transmission member 5 is distributed to the eccentric rotation member 6 and the third transmission member 9, so that the rotational force transmitted from the ring gear Cg to the differential case C can be distributed to the left and right drive axles S1, S2. it can.

  Thus, according to the transmission structure of the second embodiment, the first to third transmission members 5, 8, 9 can each be plate-like, and thus a differential device D that can be easily flattened in the axial direction can be provided. Become.

  And also in this 2nd Embodiment, since the arrangement configuration of the 2nd, 3rd transmission grooves 22 and 24 in one side 8f of the 2nd transmission member 8 is the same as that of 1st Embodiment, it is in the arrangement configuration. In relation to this, it is possible to achieve the same effect as that of the first embodiment.

  As mentioned above, although embodiment of this invention was described, this invention can perform a various design change in the range which does not deviate from the summary.

  For example, in the first embodiment, the transmission device implemented on the reduction gear R for the vehicle is exemplified, but the transmission device of the present invention is used as a reduction gear for various mechanical devices other than the vehicle. Also good.

  In the first embodiment, the reduction gear R using the first transmission shaft S1 as the input shaft and the second transmission shaft S2 as the output shaft is shown as the transmission device. However, for example, the transmission device may be the first transmission shaft S1. By using the second transmission shaft S2 as the input shaft as the output shaft, the speed increasing device may be used.

  In the second embodiment, the differential device D as a transmission device is accommodated in the transmission case 1 of the automobile. However, the differential device D is not limited to the differential apparatus for an automobile, It can be implemented as a differential for a mechanical device.

  In the second embodiment, the differential device D is applied to the left / right wheel transmission system to distribute power while allowing differential rotation to the left and right drive axles S1, S2. In the present invention, the differential device may be applied to a front / rear wheel transmission system in a front / rear wheel drive vehicle to distribute power while allowing differential rotation to the front and rear drive wheels. .

  In the second embodiment, the first and second bearings B1 and B2 are formed as cylindrical bosses and integrated with the casing C. However, the first and second casings B1 and B2 are separated from the casing C as in the first embodiment. The first and second drive axles S1 and S2 (first and second transmission shafts) may be rotatably supported on the casing C via the second bearings B1 and B2.

  In the above-described embodiment, the transmission grooves 21, 22; 24, 25 of the first and second transmission mechanisms T1, T2 are corrugated annular wave grooves along the trochoid curve. It is not limited to a form, For example, it is good also as a waveform annular wave groove along a cycloid curve.

  In the above-described embodiment, the first and second ball-shaped first and second transmission grooves 21 and 22 and the third and fourth transmission grooves 24 and 25 of the first and second transmission mechanisms T1 and T2 are provided. Although two rolling elements 23 and 26 are interposed, the rolling elements may be in the form of a roller or a pin. In this case, the first and second transmission grooves 21 and 22, and the third and fourth The transmission grooves 24 and 25 are formed in an inner surface shape so that a roller-like or pin-like rolling element can roll.

  In the above embodiment, the first and second holding members H1 and H2 are configured by an annular ring having inner and outer peripheral surfaces each having a perfect circle, but the shape of the first and second holding members is as follows. The present invention is not limited to the above embodiment, and any annular body that can hold at least a plurality of first and second balls 23 and 26 at regular intervals may be used. For example, an elliptical annular body or an annular body curved in a waveform There may be. If the first and second balls 23 and 26 can smoothly roll without the first and second holding members H1 and H2, the first and second holding members H1 and H2 may be omitted. Good.

C ··· Casing D ··· Differential gear (transmission device)
R ... Reducer (transmission device)
S1 ... 1st transmission shaft (shaft)
S2 ... 2nd transmission shaft (shaft)
T1, T2,..., First and second transmission mechanisms X1, X2,..., First and second axes 5, 8, 9, .., first, second, and third transmission members 6. 6e... Eccentric shaft portion 6j... Main shaft portions 21, 22,..., First and second transmission grooves 23, 26 .., first and second balls (first and second rolling elements)
24, 25 ... 3rd and 4th transmission groove

Claims (4)

A first transmission member (5) disposed so as to have the first axis (X1) as a central axis;
A main shaft portion (6j) rotatable around the first axis (X1) and an eccentric shaft portion (6e) having a second axis (X2) eccentric from the first axis (X1) as a central axis are integrally connected. An eccentric rotating member (6),
A plate-like second transmission member (8) that is rotatably supported by the eccentric shaft portion (6e) and faces the first transmission member (5);
A third transmission member (9) disposed so as to have the first axis (X1) as a central axis and facing the second transmission member (8);
A first transmission mechanism (T1) capable of transmitting torque while shifting between the first and second transmission members (5, 8);
A second transmission mechanism (T2) capable of transmitting torque while shifting between the second and third transmission members (8, 9);
The first transmission mechanism (T1) is located on a surface of the first transmission member (5) facing the second transmission member (8) and has a wave-shaped first shape centered on the first axis (X1). A first wave number is transmitted in a wave shape centered on the second axis (X2) on the surface of the transmission groove (21) and the second transmission member (8) facing the first transmission member (5). A second transmission groove (22) different from the groove (21) and a plurality of intersecting portions of the first and second transmission grooves (21, 22) are interposed between the first and second transmission grooves (21, 22). And a plurality of first rolling elements (23) that perform transmission transmission between the first and second transmission members (5, 8) while rolling
The second transmission mechanism (T2) is located on a surface of the second transmission member (8) facing the third transmission member (9) and has a waveform-shaped third centered on the second axis (X2). The wave number of the third transmission is a wave-shaped ring centered on the first axis (X1) on the surface of the transmission groove (24) and the third transmission member (9) facing the second transmission member (8). A fourth transmission groove (25) different from the groove (24) and a plurality of intersecting portions of the third and fourth transmission grooves (24, 25) are interposed between the third and fourth transmission grooves (24, 25). And a plurality of second rolling elements (26) for performing transmission transmission between the second and third transmission members (8, 9) while rolling),
The second transmission member (8) is disposed on one side surface (8f) in the axial direction so as to be surrounded by the second transmission groove (22) and the second transmission groove (22). A transmission device comprising three transmission grooves (24).   The first transmission member (5) is formed in an annular shape, and the third transmission member (9) is arranged such that at least a part of the first transmission member (9) is surrounded by the first transmission member (5). The transmission device according to claim 1.   The transmission device according to claim 1 or 2, wherein the third transmission groove (24) is set to have a smaller wave number than the second transmission groove (22). A casing (C) for housing the first to third transmission members (5, 8, 9) and supporting the first transmission member (5) so as not to be relatively rotatable;
One of the pair of shafts (S1, S2) arranged on the first axis (X1) (S1) is the main shaft portion (6j), and the other (S2) is the third transmission member ( The transmission device according to any one of claims 1 to 3, wherein the transmission device is connected to 9).

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