WO2018179788A1 - Planetary transmission device and differential device - Google Patents

Abstract

In the present invention a planetary plate (14) is divided into first and second planetary half-plates (14a, 14b), and only the first planetary half-plate (14a) is supported on an eccentric shaft (13). The first and second planetary half-plates (14a, 14b) are coupled to one another via an elastic member (18) that allows relative displacement of the planetary half-plates (14a, 14b) in the radial direction. Deviation between the coaxial precision of a first transmission groove (33) and a fourth transmission groove (36) and the coaxial precision of a second transmission groove (34) and a third transmission groove (35) is absorbed by the relative displacement of the planetary half-plates (14a, 14b) in the radial direction in conjunction with elastic deformation of the elastic member (18).

Description

Planetary transmission and differential

The present invention relates to a planetary transmission device and a differential device to which the planetary transmission device is applied.

Conventionally, as a planetary transmission device, for example, as described in Patent Document 1 below, first and second transmission shafts arranged so as to be relatively rotatable on a main axis line, and integrally connected to the first transmission shaft. An eccentric shaft disposed on an eccentric axis that is eccentric with respect to the main axis, a first transmission plate disposed on the main axis, and a planetary plate that is rotatably supported by the eccentric shaft and faces the first transmission plate A second transmission plate connected to the second transmission shaft so as to face the planetary plate on the opposite side of the first transmission plate, and a first transmission mechanism interposed between the first transmission plate and the planetary plate And a second speed change mechanism interposed between the planetary plate and the second transmission plate. The first speed change mechanism is formed on a side surface of the first transmission plate facing the planetary plate and has an annular waveform on the main axis. The first transmission groove is centered on the surface of the planetary plate and is formed on one side of the planetary plate facing the first transmission plate, and has a wave number different from that of the first transmission groove. A second transmission groove centered on the eccentric axis in a ring-shaped waveform, and a plurality of first rolling transmission members rotatably mounted in both transmission grooves at the overlapping portion of the first and second transmission grooves The second transmission mechanism is formed on the other side of the planetary plate, is formed on the side of the second transmission plate facing the planetary plate, and a third transmission groove centered on the eccentric axis in an annular waveform. A fourth transmission groove centered on the main axis in an annular waveform having a wave number different from that of the third transmission groove, and a plurality of rolling grooves interposed between the third and fourth transmission grooves at the overlapping portions of the third and fourth transmission grooves. What contains a 2nd rolling transmission member is known.

Japanese Patent No. 4814351

In such a planetary transmission device, the first and fourth transmission grooves to be arranged on the main axis and the coaxial accuracy and the eccentric axis are arranged due to manufacturing errors and assembly errors of the first and second transmission mechanisms. When there is a deviation in the coaxial accuracy of the second and third transmission grooves and the phase accuracy between the second and third transmission grooves, a large frictional resistance is generated in each transmission mechanism, causing transmission. The efficiency will be reduced. Therefore, high precision is required for manufacturing and assembling the first and second transmission mechanisms in order to avoid such inconvenience, but this requirement causes an increase in manufacturing cost.

The present invention has been made in view of such circumstances, and even if there is some deviation as described above due to manufacturing errors and assembly errors of the first and second transmission mechanisms, the deviation is absorbed and smooth operation is possible. It is an object of the present invention to provide a planetary transmission device that can suppress an increase in manufacturing cost and a differential device to which the planetary transmission device is applied.

In order to achieve the above object, according to the present invention, first and second transmission shafts arranged so as to be relatively rotatable on a main axis, and integrally connected to the first transmission shaft, An eccentric shaft disposed on an eccentric eccentric axis, a first transmission plate disposed on the main axis, a planetary plate supported rotatably on the eccentric shaft and opposed to the first transmission plate, and the planet A second transmission plate facing the plate on the opposite side to the first transmission plate and coupled to the second transmission shaft; and a first transmission mechanism interposed between the first transmission plate and the planetary plate And a second transmission mechanism interposed between the planetary plate and the second transmission plate, and the first transmission mechanism is formed on a side surface of the first transmission plate facing the planetary plate, A first transmission groove centered on the main axis in an annular waveform, and a side surface of the planetary plate facing the first transmission plate; A second transmission groove that is centered on the eccentric axis with an annular waveform having a wave number different from that of the first transmission groove, and can freely roll to both transmission grooves at the overlapping portion of the first and second transmission grooves. And a second transmission mechanism formed on the other side of the planetary plate and centered on the eccentric axis in an annular waveform, and a second transmission mechanism. , A fourth transmission groove formed on a side surface of the second transmission plate facing the planetary plate and having a wave number different from that of the third transmission groove and centered on the main axis, and the third and fourth transmission grooves. A planetary transmission device including a plurality of second rolling transmission members that are rotatably inserted in the transmission grooves at an overlapping portion of the transmission grooves, wherein the planetary plates are arranged in the axial direction; Divided into two planetary plate halves and the first and second planetary plate halves Only the planetary plate half is rotatably supported on the eccentric shaft, and the first and second planetary plate halves are elastic members that allow relative displacement in the radial direction of the first and second planetary plate halves. The first feature is that they are connected to each other.

The first and second transmission shafts respectively correspond to first and second output shafts 19 and 20 in the embodiments of the present invention described later, and the first and second transmission plates are the input plate 12 and the output. The first and second rolling transmission members respectively correspond to the plates 15 and correspond to the first and second transmission balls 37 and 38, respectively.

According to the present invention, the first and second transmission shafts are arranged so as to be rotatable relative to each other on the main axis, and are arranged on an eccentric axis that is integrally connected to the first transmission shaft and eccentric with respect to the main axis. An eccentric shaft, a first transmission plate disposed on the main axis, a planetary plate supported by the eccentric shaft so as to be able to rotate, and facing the first transmission plate, and the planetary plate with the first transmission plate A second transmission plate facing the opposite side of the plate and coupled to the second transmission shaft; a first transmission mechanism interposed between the first transmission plate and the planetary plate; the planetary plate and the A second transmission mechanism interposed between the second transmission plates, wherein the first transmission mechanism is formed on a side surface of the first transmission plate facing the planetary plate and has an annular waveform on the main axis. A first transmission groove located at the center and one side surface of the planetary plate facing the first transmission plate; A second transmission groove centered on the eccentric axis with an annular waveform having a wave number different from that of the first transmission groove, and a plurality of second transmission grooves interposed between the first and second transmission grooves so as to roll freely. The second transmission mechanism is formed on the other side surface of the planetary plate, and has a third transmission groove centered on the eccentric axis in an annular waveform, and the second transmission plate, A fourth transmission groove formed on a side surface opposite to the planetary plate and centered on the main axis in an annular waveform having a wave number different from that of the third transmission groove; A planetary transmission device including a plurality of second rolling transmission members interposed rotatably in a transmission groove, wherein the planetary plate is divided into first and second planetary plate halves arranged in the axial direction. And at least the first planetary plate half is rotatably supported on the eccentric shaft. It said first and second planetary plate halves, the second feature to be connected to each other via the elastic member to allow rotation direction of the relative displacement of the first and second planetary plate halves.

Further, in the present invention, in addition to the first or second feature, the elastic member is provided with a preload that urges the first and second planetary plate halves in a direction away from each other in the axial direction. This is the third feature.

Further, in the present invention, in addition to any of the first to third features, an accommodation space is provided between the first and second planetary plate halves, and the accommodation space includes the first transmission shaft. A fourth feature is that a counterweight that is attached and suppresses rotational unbalance of an eccentric rotating body including the eccentric shaft and the planetary plate is arranged.

Furthermore, in the present invention, a differential device to which any one of the first to fourth features is applied, wherein the first and second cylinder shafts that are rotatably supported by the transmission case on the main axis are respectively centered. A differential case that has first and second case side walls formed thereon, and receives rotational power from the outside; and an input plate as the first transmission plate that is coupled to the first case side wall so as to be integrally rotatable; First and second output shafts as the first and second transmission shafts disposed on the main axis line in the differential case, and rotational power received in the differential case and transmitted from the differential case to the input plate. A differential mechanism that distributes to the first and second output shafts, and the differential mechanism is supported by the eccentric shaft that is integrally connected to the first output shaft, and rotatably supported by the eccentric shaft. And the planetary plate facing the input plate An output plate as the second transmission plate, opposed to the planet plate on the opposite side of the input plate, and supported in the axial direction on the second case side wall while being connected to the second output shaft; The first speed change mechanism interposed between the input plate and the planetary plate; and the second speed change mechanism interposed between the planetary plate and the output plate. A fifth drive shaft is rotatably connected to the first tube shaft, and a second drive shaft rotatably connected to the second tube shaft is connected to the second output shaft. It is characterized by.

According to the first feature of the present invention, due to manufacturing errors and assembly errors of the first and second transmission mechanisms, the coaxial accuracy of the first transmission groove and the fourth transmission groove to be arranged on the main axis, and the eccentric axis If the coaxial accuracy of the second transmission groove and the third transmission groove that are to be arranged in the first and second transmission grooves is somewhat out of order, the first and second planetary plate halves are elastically deformed to cause the first and second planetary plate halves to be elastically deformed. The second planetary plate half is relatively displaced in the radial direction to absorb the deviation. For this reason, the smooth operation of the first and second transmission mechanisms can be ensured without being interfered by the deviation. As a result, the manufacturing accuracy and assembly accuracy of each transmission mechanism are eased, and an increase in manufacturing cost can be suppressed.

According to the second feature of the present invention, when the phase of the second transmission groove and the third transmission groove is somewhat out of order due to manufacturing errors or assembly errors of the first and second transmission mechanisms, Due to the elastic deformation of the elastic member that connects the second planetary plate halves, the first and second planetary plate halves are relatively displaced in the direction of rotation, and the deviation is absorbed. For this reason, the smooth operation of the first and second speed change mechanisms can be ensured without being interfered with by the deviation. As a result, the manufacturing accuracy and assembly accuracy of each transmission mechanism are eased, and an increase in manufacturing cost can be suppressed.

According to the third feature of the present invention, the backlash of the first and second transmission mechanisms is made zero by the axial preload applied to the elastic member connecting the first and second planetary plate halves, Alternatively, the two speed change mechanisms can be operated more smoothly.

According to the fourth feature of the present invention, the counterweight attached to the first transmission shaft is disposed by using the accommodation space provided between the first and second planetary plate halves, thereby providing the counterweight. The planetary transmission can be made compact. In addition, the offset amount of the center of gravity of the counterweight on the main axis with respect to the center of gravity of the eccentric rotating body including the eccentric shaft and the planetary plate can be reduced, and the couple caused by the centrifugal force acting on both the centers of gravity can be kept small.

According to the fifth aspect of the present invention, the planetary transmission device can be applied to a differential device. Therefore, the differential device can exhibit the same effect as the planetary transmission device.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a longitudinal front view of a differential device according to Embodiment 1 of the present invention. FIG. 2 is a sectional view taken along line 2-2 of FIG. FIG. 3 is a sectional view taken along line 3-3 in FIG. 1. FIG. 4 is a sectional view taken along line 4-4 of FIG. FIG. 5 is a sectional view taken along line 5-5 in FIG. The longitudinal section front view of the differential which concerns on Example 2 of this invention. FIG. 7 is a cross-sectional view taken along line 7-7 in FIG.

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

In FIG. 1, a differential device D as a planetary transmission is housed in a transmission case 1 of a vehicle together with a transmission, and rotational power output from the transmission is connected to left and right drive wheels of the vehicle. It is used for distributing to the first and second drive shafts S1, S2.

The differential case 2 of the differential device D includes a pair of left and right first and second case side walls 2a and 2b that are opposed to each other at an interval, and the outer peripheral ends of the first and second case side walls 2a and 2b are integrally formed. And a ring gear 4 connected to the. Therefore, the ring gear 4 is a component of the differential case 2. The ring gear 4 meshes with the output gear 3 of the transmission to receive the output of the transmission.

In the illustrated example, spigot fitting and welding are used as connecting means between the first and second case side walls 2a, 2b and the ring gear 4, but bolts, caulking, or the like can also be used. The first and second case side walls 2a and 2b are provided with a plurality of through holes 44 and 45 for allowing lubricating oil to flow between the differential case 2 and the transmission case 1, respectively.

The first and second case side walls 2a and 2b integrally have first and second cylinder shafts 5 and 6 that protrude outward and are aligned on the main axis X1, and these first and second cylinders are integrated. The shafts 5 and 6 are rotatably supported by the mission case 1 via first and second ball bearings 7 and 8. Further, the first and second drive shafts S1 and S2 are rotatably supported by the first and second cylinder shafts 5 and 6, respectively. Further, the transmission case 1 includes first and second oil seals 10 and 11 for bringing a seal lip into close contact with the outer periphery of the first and second drive shafts S1 and S2 outside the first and second ball bearings 7 and 8, respectively. Installed. A plurality of first and second spiral grooves 49 and 50 capable of transferring lubricating oil are formed on the inner peripheral surfaces of the first and second cylindrical shafts 5 and 6.

The differential case 2 is splined to the first drive shaft S1 and disposed on the main axis X1, and the first output shaft 19 is splined to the second drive shaft S2 and disposed on the main axis X1. A second output shaft 20 and a planetary differential mechanism 21 that distributes rotational power input from the output gear 3 to the ring gear 4 to the first and second output shafts 20 are accommodated.

The differential mechanism 21 includes an input plate 12 that is integrally coupled to the first case side wall 2a, and an eccentric axis X2 that is integrally connected to the first output shaft 19 and is eccentric by a predetermined distance e from the main axis X1. An eccentric shaft 13, an annular planetary plate 14 that is rotatably supported by the eccentric shaft 13 via a third ball bearing 9 and faces the input plate 12, and between the input plate 12 and the planetary plate 14. The first transmission mechanism 26 interposed between the first planetary plate 14 and the planetary plate 14 on the opposite side of the input plate 12 and the annular output plate 15 connected to the second output shaft 20, and the planetary plate 14 and And a second speed change mechanism 27 interposed between the output plates 15. The output plate 15 is axially supported on the inner surface of the second case side wall 2b via the annular first thrust washer 31. . A second thrust washer 32 for adjusting a gap between the first case side wall 2a and the first output shaft 19 in the axial direction is interposed. A plurality of radially extending oil grooves 46, 47 are provided on the inner surfaces of the first and second case side walls 2a, 2b that are in contact with the first and second thrust washers 31, 32.

In the illustrated example, the first case side wall 2a and the input plate 12 are integrally formed as a single part, but they may be individually configured and connected to each other by a spline or the like.

As shown in FIGS. 1 and 2, the first speed change mechanism 26 includes an annular wave-shaped first transmission groove 33 formed on a side surface of the input plate 12 facing the planetary plate 14, and the input plate of the planetary plate 14. 12 is formed on one side surface opposite to the first transmission groove 33 and has an annular corrugated second transmission groove 34 having a wave number smaller than that of the first transmission groove 33, and both the transmission grooves 33, in the overlapping portion of the first and second transmission grooves 33, 34, 34, a plurality of first transmission balls 37 that are rotatably arranged and arranged at equal intervals, and a first annular ball that is rotatably disposed between the input plate 12 and the planetary plate 14 and holds the first transmission balls 37. And a retainer plate 39. The first retainer plate 39 has the same number of holding holes 39a as the first transmission balls 37 and are arranged at equal intervals on the same circumference, and the first transmission balls 37 are rotatably held by these holding holes 39a. It is like that.

As shown in FIGS. 1 and 3, the second speed change mechanism 27 includes a ring-shaped third transmission groove 35 formed on the other side of the planetary plate 14 facing the output plate 15, and the output plate 15. An annular corrugated fourth transmission groove 36 formed on a side surface facing the planetary plate 14 and having a wave number smaller than that of the third transmission groove 35, and both transmission grooves 35 in the overlapping portion of the third and fourth transmission grooves 35, 36. , 36 and a plurality of second transmission balls 38 arranged at equal intervals and rotatably arranged between the planetary plate 14 and the output plate 15 to hold the second transmission ball 38. And 2 retainer plates 40. The second retainer plate 40 has the same number of holding holes 40a as the second transmission balls 38 and is arranged at equal intervals on the same circumference, and the first transmission balls 37 are rotatably held by these holding holes 40a. It is like that.

In the illustrated example, the first transmission groove 33 and the third transmission groove 35 are formed along an endless hypocycloid curve or hypotrochoid curve, and the second transmission groove 34 and the fourth transmission groove 36 are endless epicycloid curves. Alternatively, it is formed along an epitrochoid curve. The first transmission groove 33 and the fourth transmission groove 36 are centered on the main axis X1, and the second transmission groove 34 and the third transmission groove 35 are centered on the eccentric axis X2.

In the above, when the wave number of the first transmission groove 33 is Z1, the wave number of the second transmission groove 34 is Z2, the wave number of the third transmission groove 35 is Z3, and the wave number of the fourth transmission groove 36 is Z4, The four transmission grooves 33 to 36 are formed so as to satisfy the following expressions (1) to (3).
(Z1 / Z2) × (Z3 / Z4) = 2 (1)
Z1-Z2 = 2 (2)
Z3-Z4 = 2 (3)

Therefore, specifically, as in the illustrated example, Z1 = 8, Z2 = 6, Z3 = 6, Z4 = 4, or Z1 = 6, Z2 = 4, Z3 = 8, and Z4 = 6. .

Thus, in the illustrated example, the eight-wave first transmission groove 33 and the six-wave second transmission groove 34 are overlapped at seven locations, and the seven transmission grooves 33 and 34 have seven grooves at the seven overlapping portions. The first transmission ball 37 is interposed, and the six-wave third transmission groove 35 and the four-wave fourth transmission groove 36 overlap at five locations, and the five transmission grooves 35 and 36 overlap with the five overlapping portions. Five second transmission balls 38 are interposed.

Next, in FIGS. 1 and 4, the planetary plate 14 is divided into a first planetary plate half 14 a and a second planetary plate half 14 b aligned in the axial direction, and only the first planetary plate half 14 a is formed on the eccentric shaft 13. The third ball bearing 9 is rotatably supported. The planetary plate halves 14 a and 14 b are connected via an elastic member 18. The elastic member 18 is molded from rubber or elastic synthetic resin. Thus, the second transmission groove 34 is formed on the outer surface of the first planetary plate half 14a, and the third transmission groove 35 is formed on the outer surface of the second planetary plate half 14b.

In the illustrated example, a plurality of pin-shaped convex portions 16 arranged at equal intervals in the circumferential direction are provided on the surface of the first planetary plate half 14a facing the second planetary plate half 14b, while the second planetary plate A plurality of concave portions 17 that receive the convex portions 16 are provided on the surface of the half body 14 b facing the first planetary plate half body 14 a so as to be arranged at equal intervals in the circumferential direction, and a cap is provided between the convex portions 16 and the concave portions 17. A shaped elastic member 18 is interposed. At that time, the phases of the second transmission groove 34 and the third transmission groove 35 are matched as prescribed. In addition, a gap g is provided between the opposing surfaces of both planetary plate halves 14a and 14b.

Thus, the elastic member 18 is disposed so as to allow constant relative displacement in the radial direction, the rotation direction, and the axial direction of the planetary plate halves 14a and 14b by elastic deformation thereof.

Further, the elastic member 18 is given an axial preload that urges the first and second planetary half halves 14a and 14b in a direction to separate them from each other. Specifically, the elastic member 18 is axially compressed and deformed between the tip surface of the convex portion 16 and the bottom surface of the concave portion 17, and the repulsive force causes the first and second planetary plate halves 14 a and 14 b to interact with each other. It will be energized in the direction to separate.

Next, in FIGS. 1, 3 and 5, the second planetary plate half 14 b is formed between the first and second planetary plate halves 14 a, 14 b with a bottomed cylinder comprising a cylindrical portion 22 and an end wall portion 23. The storage space 42 is provided by comprising in a shape. An inner end portion of the first output shaft 19 extends toward the accommodation space 42, and a counterweight 43 fixed to the inner end portion is accommodated in the accommodation space 42. At this time, the weight portion 43a of the counterweight 43 is disposed in an opposite phase to the eccentric shaft 13 with the main axis X1 interposed therebetween. The cylindrical portion 22 of the first planetary plate half 14a is provided with a plurality of lightening holes 29. The recess 17 is provided on the end surface of the cylindrical portion 22, and the third transmission groove 35 is provided on the outer surface of the end wall portion 23.

Thus, when the first output shaft 19 is rotated, the centrifugal force acting on the center of gravity G2 of the counterweight 43 is opposed to the centrifugal force acting on the center of gravity G1 of the eccentric rotating body including the eccentric shaft 13 and the planetary plate 14. The rotational unbalance of the eccentric rotating body is made zero or suppressed.

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

Suppose that the first drive shaft S1 is fixed to keep the first output shaft 19 stationary, and rotational power is input from the transmission output gear 3 to the ring gear 4.

When the ring gear 4 is rotated by the input from the output gear 3, the rotation is transmitted to the input plate 12 integral with the differential case 2, and therefore the first case side wall 2a, and the input plate 12 rotates around the main axis X1. By the rotation of the input plate 12, the eight-wave first transmission groove 33 of the input plate 12 drives the six-wave second transmission groove 34 of the first planetary plate half body 14a via the first transmission ball 37, and Since the driving force is simultaneously transmitted to the second planetary plate half 14b via the elastic member 18, the input plate 12 has the speed increase ratio of 8/6, that is, the first and second planetary plate halves 14a, 14b, The planetary plate 14 is rotated about the eccentric axis X2. According to the rotation of the planetary plate 14, the sixth transmission groove 35 of the planetary plate 14 drives the fourth transmission groove 36 of the output plate 15 via the second transmission ball 38. The output plate 15 is rotated with a speed increasing ratio of 6/4. Eventually, the input plate 12 is composed of the output plate 15 and the second output shaft 20 connected thereto with a speed increasing ratio of (Z1 / Z2) × (Z3 / Z4) = (8/6) × (6/4) = 2. Will be rotated.

Further, it is assumed that the second output shaft 20 is fixed by fixing the second drive shaft S2 and rotational power is input to the ring gear 4 from the output gear 3 of the transmission.

When the input plate 12 is rotated by the input from the ring gear 4, the input plate 12 is driven to the planetary plate 14 (first and second planetary plate halves 14 a and 14 b), and the planetary plate 14 is driven to the stationary output plate 15. Due to the reaction force, the planetary plate 14 revolves around the main axis X1 while rotating around the eccentric shaft 13, thereby rotating the eccentric shaft 13 around the main axis X1. As a result, the input plate 12 rotates the first output shaft 19 with a double speed increasing ratio.

These facts indicate that the differential mechanism 21 can exhibit a differential function in which the rotational speed of the input plate 12 and the average value of the rotational speeds of the first and second output shafts 19 and 20 are always equal. Means. Thus, the differential mechanism 21 can distribute the rotational power of the input plate 12 to the first and second output shafts 19 and 20 according to their loads.

During this time, the rotational torque of the input plate 12 is applied to the planetary plate 14 (first and second planetary plate halves 14a and 14b) via the first transmission groove 33, the plurality of first transmission balls 37 and the second transmission groove 34. The rotational torque of the planetary plate 14 is transmitted to the output plate 15 through the third transmission groove 35, the plurality of second transmission balls 38 and the fourth transmission groove 36, respectively. Between the planetary plate 14 and the output plate 15, torque transmission is performed in a distributed manner at a plurality of locations where the first and second transmission balls 37 and 38 are present, and the durability of the differential mechanism 21 is improved. It is possible to reduce the weight and contribute to the provision of the differential device D that can withstand a high load while being small.

The first and second retainer plates 39 and 40 hold a plurality of first and second transmission balls 37 and 38 to restrict their equidistant arrangement, and also part of the first transmission during torque transmission. When rampage occurs in the ball 37 or the second transmission ball 38, it cooperates with the other plurality of first transmission balls 37 or the second transmission ball 38 to suppress the rampage of the part of the transmission balls. , Smooth torque transmission by the first and second transmission balls 37 and 38 is ensured.

By the way, the planetary plate 14 is divided into first and second planetary plate halves 14a and 14b arranged in the axial direction, and only the first planetary plate half 14a is rotatably supported by the eccentric shaft 13, and The first and second planetary plate halves 14a and 14b are elastic members interposed between the plurality of convex portions 16 of the first planetary plate half 14a and the plurality of concave portions 17 of the second planetary plate half 14b. 18, the planetary plate halves 14 a and 14 b are connected so as to allow relative displacement in the radial direction and the rotation direction. Therefore, due to manufacturing errors and assembly errors of the first and second transmission mechanisms 26 and 27, The coaxial accuracy of the first transmission groove 33 and the fourth transmission groove 36 to be arranged on the line X1 and the coaxial accuracy of the second transmission groove 34 and the third transmission groove 35 to be arranged on the eccentric axis X2 If there is a deviation, the planetary plate 14 Compressive deformation in the radial direction is applied, the first and second planetary plate halves 14a, 14b are the deviations is absorbed by relative displacement in the radial direction.

Further, when the phase of the second transmission groove 34 and the third transmission groove 35 formed on both side surfaces of the planetary plate 14 is somewhat out of phase, the elastic member 18 is subjected to compression deformation in the rotation direction of the planetary plate 14. Given the above, the first and second planetary plate halves 14a and 14b are relatively displaced in the direction of rotation, so that the above-mentioned deviation is absorbed.

Thus, the smooth operation of the first and second transmission mechanisms 26 and 27 and the differential mechanism 21 can be ensured without being interfered by the various deviations as described above. Therefore, the manufacturing accuracy and assembly accuracy of each of the transmission mechanisms 26 and 27 are eased, and an increase in manufacturing cost can be suppressed.

Further, since the elastic member 18 is provided with an axial preload that urges the first and second planetary half halves 14a and 14b in a direction away from each other, the output plate 15 is connected to the second case side wall. 2b, the first transmission ball 37 is in pressure contact with the first and second transmission grooves 33, 34, and the second transmission ball 38 is in the third and fourth transmission grooves 35, 36, each of which is always maintained in a pressure contact state with 36, thereby eliminating the play in the axial direction of the output plate 15, reducing the backlash of the first and second transmission mechanisms 26, 27, and differentially. The mechanism 21 can be operated more smoothly. As described above, the output plate 15 is kept in pressure contact with the second case side wall 2b, so that the first thrust washer 31 interposed between the output plate 15 and the second case side wall 2b has a shim function. Therefore, the first thrust washer 31 can be omitted.

Also, the elastic member 18 is useful for absorbing torque fluctuations caused by fluctuations in input power and load.

In addition, a counterweight 43 attached to the first output shaft 19 is arranged in the accommodating space 42 provided between the first and second planetary plate halves 14a and 14b, so that the planetary difference with the counterweight 43 is provided. The moving device D can be configured compactly. In addition, the offset s of the center of gravity G2 of the counterweight 43 on the main axis X1 with respect to the center of gravity G1 of the eccentric rotating body including the eccentric shaft 13 and the planetary plate 14 can be made zero or small. Couples due to centrifugal force acting on G2 can be suppressed.

In the differential device D according to the second embodiment of the present invention, as shown in FIGS. 6 and 7, one of the first and second planetary plate halves 14a and 14b has an inner cylindrical portion having an uneven outer peripheral surface 24a. 24 is provided, and on the other side, an outer cylinder portion 25 having an uneven inner peripheral surface 25a is provided. The inner cylinder portion 24 and the outer cylinder portion 25 are inlay-fitted with each other so as to sandwich an elastic member 18 ′ having an L-shaped cross section between the concave / convex outer peripheral surface 24 a and the concave / convex inner peripheral surface 25 a. At that time, the phases of the second transmission groove 34 and the third transmission groove 35 are matched as prescribed. Since the other configuration is the same as that of the first embodiment, the same reference numerals are given to the portions corresponding to the first embodiment in FIGS. 6 and 7, and the detailed description thereof will be omitted.

Also in the second embodiment, the first and second planetary plate halves 14a and 14b and the elastic member 18 'can exhibit the same functions and effects as those of the first embodiment.

Note that the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the scope of the invention.

For example, the differential device D can be applied to a central differential device (center differential) for driving front and rear wheels in a front and rear wheel drive vehicle. Further, the differential case 2 is configured as a stationary gear case, the first output shaft 19 is a drive shaft connected to, for example, an electric motor, and the second output shaft 20 is a driven shaft connected to a load. By appropriately setting the gear ratios of the mechanisms 26 and 27, the present invention can be applied to a speed reducer or a speed increasing device. The first and second transmission balls 37 and 38 can be replaced by rollers, respectively.

D. ・ Differential gear S1 ・ ・ First drive shaft S2 ・ ・ Second drive shaft X1 ・ ・ Main axis X2 ・ ・ Eccentric shaft 1 ・ ・ Mission case 2 ・ ・ Differential case 2a ・ ・ First case side wall 2b ・ ・2 Case side wall 5 ・ ・ First cylinder shaft 6 ・ ・ Second cylinder shaft 12 ・ ・ First transmission plate (input plate)
13. · Eccentric shaft 14 ·· Planet plate 14a ·· First planetary plate half 14b ·· Second planetary plate half 15 ·· Second transmission plate (output plate)
18, 18 '... Elastic member 19. First transmission shaft (first output shaft)
20. ・ Second transmission shaft (second output shaft)
21. ・ Differential mechanism 26 ・ ・ First transmission mechanism 27 ・ ・ Second transmission mechanism 33 ・ ・ First transmission groove 34 ・ ・ Second transmission groove 35 ・ ・ Third transmission groove 36 ・ ・ Fourth transmission groove 37 ・・ First rolling transmission member (first transmission ball)
38 .. Second rolling transmission member (second transmission ball)
42 ... Containment space 43 ... Counterweight

Claims (5)

A first transmission shaft and a second transmission shaft which are arranged to be relatively rotatable on the main axis; an eccentric shaft which is integrally connected to the first transmission shaft and which is arranged on an eccentric axis which is eccentric with respect to the main axis; , A first transmission plate disposed on the main axis, a planetary plate that is rotatably supported by the eccentric shaft and faces the first transmission plate, and the planetary plate on a side opposite to the first transmission plate. Oppositely, a second transmission plate coupled to the second transmission shaft, a first transmission mechanism interposed between the first transmission plate and the planetary plate, and between the planetary plate and the second transmission plate A second speed change mechanism interposed in the
The first transmission mechanism is formed on a side surface of the first transmission plate facing the planetary plate, and has a first transmission groove centered on the main axis in an annular waveform, and the first transmission of the planetary plate. A second transmission groove formed on one side facing the plate and centered on the eccentric axis in an annular waveform having a wave number different from that of the first transmission groove; and at an overlapping portion of the first and second transmission grooves A plurality of first rolling transmission members that are rotatably inserted in both transmission grooves,
The second speed change mechanism is formed on the other side surface of the planetary plate, and has a third transmission groove centered on the eccentric axis in an annular waveform, and a side surface of the second transmission plate facing the planetary plate. A fourth transmission groove that is formed and is centered on the main axis in an annular waveform having a wave number different from that of the third transmission groove; and an overlapping portion of the third and fourth transmission grooves is provided so as to be freely rollable in both the transmission grooves. A planetary transmission device including a plurality of second rolling transmission members mounted,
The planetary plate is divided into first and second planetary plate halves arranged in the axial direction, and only the first planetary plate half of the first and second planetary plate halves can rotate to the eccentric shaft. Supported by
The planetary transmission apparatus, wherein the first and second planetary plate halves are connected to each other via an elastic member that allows relative displacement in the radial direction of the first and second planetary plate halves. . A first transmission shaft and a second transmission shaft which are arranged to be relatively rotatable on the main axis; an eccentric shaft which is integrally connected to the first transmission shaft and which is arranged on an eccentric axis which is eccentric with respect to the main axis; , A first transmission plate disposed on the main axis, a planetary plate that is rotatably supported by the eccentric shaft and faces the first transmission plate, and the planetary plate on a side opposite to the first transmission plate. Oppositely, a second transmission plate coupled to the second transmission shaft, a first transmission mechanism interposed between the first transmission plate and the planetary plate, and between the planetary plate and the second transmission plate A second speed change mechanism interposed in the
The first transmission mechanism is formed on a side surface of the first transmission plate facing the planetary plate, and has a first transmission groove centered on the main axis in an annular waveform, and the first transmission of the planetary plate. A second transmission groove formed on one side facing the plate and centered on the eccentric axis in an annular waveform having a wave number different from that of the first transmission groove; and at an overlapping portion of the first and second transmission grooves A plurality of first rolling transmission members that are rotatably inserted in both transmission grooves,
The second speed change mechanism is formed on the other side surface of the planetary plate, and has a third transmission groove centered on the eccentric axis in an annular waveform, and a side surface of the second transmission plate facing the planetary plate. A fourth transmission groove that is formed and is centered on the main axis in an annular waveform having a wave number different from that of the third transmission groove; and an overlapping portion of the third and fourth transmission grooves is provided so as to be freely rollable in both the transmission grooves. A planetary transmission device including a plurality of second rolling transmission members mounted,
The planetary plate is divided into first and second planetary plate halves arranged in the axial direction, and at least the first planetary plate half is supported to be rotatable about the eccentric shaft,
The planetary transmission device, wherein the first and second planetary plate halves are connected to each other via an elastic member that allows relative displacement in the rotation direction of the first and second planetary plate halves. . The planetary transmission device according to claim 1 or 2,
The elastic member is applied with a preload that urges the first and second planetary plate halves in a direction away from each other in the axial direction. The planetary transmission device according to any one of claims 1 to 3,
An accommodation space is provided between the first and second planetary plate halves, and the accommodation space is attached to the first transmission shaft for rotational unbalance of the eccentric rotating body including the eccentric shaft and the planetary plate. A counterweight to be suppressed is arranged. A differential device to which the planetary transmission device according to any one of claims 1 to 4 is applied,
A differential case that has first and second case side walls formed at the center of first and second cylindrical shafts that are rotatably supported by the transmission case on the main axis, and that receives rotational power from the outside; An input plate as the first transmission plate coupled to the side wall of the first case so as to be integrally rotatable, and first and second as the first and second transmission shafts disposed on the main axis in the differential case. Two output shafts, and a differential mechanism that is housed in the differential case and distributes rotational power transmitted from the differential case to the input plate to the first and second output shafts,
The differential mechanism includes the eccentric shaft that is integrally connected to the first output shaft, the planetary plate that is rotatably supported by the eccentric shaft and faces the input plate, and the planetary plate that includes the planetary plate. An output plate as the second transmission plate, opposed to the input plate on the opposite side, and supported in the axial direction on the second case side wall while being connected to the second output shaft, the input plate and the planetary plate The first transmission mechanism interposed therebetween, and the second transmission mechanism interposed between the planetary plate and the output plate,
The first output shaft has a first drive shaft rotatably supported by the first tube shaft, and the second output shaft has a second drive shaft rotatably supported by the second tube shaft. Each is connected.

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