JP2017180743A - Transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure an installation space of a retainer between both transmission members while making thrust load between transmission grooves and rolling elements during transmission zero or sufficiently reducing the same, in a transmission device in which one of the transmission members applies a first axis as a central axis, the other transmission member is revolvable around the first axis while rotating around a second axis eccentric from the first axis, and a transmission mechanism between both transmission members has one of transmission grooves formed on one of the transmission members and formed into the corrugated annular shape on the first axis, the other transmission groove formed on the other transmission member and formed into the corrugated annular shape on the second axis, and the plurality of rolling elements disposed on a plurality of intersecting portions of both transmission grooves.SOLUTION: Both transmission grooves 21, 22 are composed of angular grooves having an U-shaped cross section, and rolling elements rolling in the angular grooves are composed of rollers extended over both transmission grooves, and having the curved shape in which a roller outer peripheral face is gradually reduced in outer diameter from contact portion outer end toward both end faces in a region from a contact portion t opposed to a transmission groove inner face to both end faces f of the roller 23.SELECTED DRAWING: Figure 1

Description

  The present invention includes a transmission device, particularly a pair of transmission members facing each other, and a transmission mechanism provided between the transmission members and capable of transmitting torque while shifting between the transmission members. The present invention relates to a transmission device in which a transmission member has a first axis as a central axis, and the other transmission member can revolve around a first axis while rotating around a second axis that is eccentric from the first axis.

  For example, as shown in FIG. 7 of Patent Document 1, the above transmission device is conventionally known. In this device, the speed change mechanism is located on the surface of one transmission member facing the other transmission member and has a first axis. A wave-shaped transmission groove centered on the other side of the other transmission member and the other transmission member on the surface facing the one transmission member and a wave-shaped ring centered on the second axis and having a different wave number from the one transmission groove And a plurality of rolling elements interposed at a plurality of intersections of the two transmission grooves, and a holding hole for holding the rolling elements at intervals in the circumferential direction. Holding member (retainer). And in the transmission device of this structure, there exists an advantage which can attain axial size reduction of an apparatus by forming each transmission member in plate shape, for example.

JP 2010-14214 A

  By the way, in this type of transmission device, as shown in FIG. 7 of Patent Document 1, both transmission grooves are formed in a V-shaped cross section or a Gothic arch shape, while the rolling elements are formed of balls. Therefore, during transmission, a large thrust load is generated between each transmission groove and the ball, which increases the frictional force between the transmission groove and the ball, or a thrust receiving portion that is in sliding contact with the rotating transmission member and its back surface. (For example, when the transmission device is a differential device, a differential case, and when the transmission device is a transmission case) the frictional force between the transmission device and the transmission efficiency may be reduced.

  Therefore, in order to suppress the above inconvenience, for example, a contact angle of the ball with respect to the transmission groove (that is, a direction in which the ball acts on the transmission groove (in other words, a straight line (normal line) from the ball center to the contact point of the ball and the transmission groove) It is conceivable to set a large angle between the direction of the thrust and the direction of the thrust component of the load). In this case, however, another inconvenience may occur as follows.

  That is, if the contact angle is set large, the thrust load can be reduced. However, as the contact angle is set larger, the depth of penetration of the ball into the transmission groove becomes deeper, and the two transmission members face each other. Since the interval is narrow, it is difficult to secure an installation space for the holding member that holds the plurality of balls.

  The present invention has been made in view of such circumstances, and while the thrust load between the transmission groove and the rolling element during transmission is zero or sufficiently reduced, the holding member for holding the rolling element is installed between the two transmission members. An object of the present invention is to provide a transmission that can secure a sufficient space.

  In order to achieve the above object, the present invention includes a pair of transmission members facing each other, and a transmission mechanism that is provided between the transmission members and capable of transmitting torque while shifting between the transmission members. And the other transmission member can revolve around the first axis while rotating around the second axis eccentric from the first axis, and the pair of transmissions Each of the members has a transmission groove on both opposing surfaces, and the transmission mechanism is provided on the one transmission member and has one of the transmission grooves forming a corrugated ring centered on the first axis. The other transmission member, which is provided in the other transmission member and has a corrugated annular shape centering on the second axis and has a wave number different from that of the one transmission groove, the one transmission groove, and the other transmission groove Interspersed at multiple intersections, both transmissions A plurality of rolling elements that perform transmission transmission between the two transmission members while rolling, and a plurality of holding holes that hold the rolling elements at intervals in the circumferential direction, and are interposed between the two transmission members. The transmission member is a square groove having a U-shaped cross section, and the rolling element extends between the transmission grooves. Both ends are composed of rollers that can roll on the inner surfaces of both transmission grooves, and each roller has an outer peripheral surface in the region from each contact portion to the inner surfaces of both transmission grooves to both axial end surfaces. However, it has a curved surface shape in which the outer diameter is smoothly reduced from the contact portion toward the both end surfaces, and the outer peripheral surface of the axially intermediate portion of each roller can be slid into the holding hole of the holding member. The first feature is that it is formed of a cylindrical surface that is fitted and supported by the cylinder.

  According to the present invention, in addition to the first feature, the inner peripheral surface of the holding hole that fits and supports the intermediate portion in the axial direction of each roller is centered on a cross-sectional shape including the center line of the holding hole. The second feature is that the line has a convex arc shape.

  Further, according to the present invention, in addition to the first or second feature, the opposing inner surface of each of the transmission grooves is expanded in a pre-expanded manner toward the open surface side of the groove with a predetermined minute taper angle. The third feature is that

  In the third feature of the present invention, the “predetermined minute taper angle” refers to a case where a transmission member provided with a transmission groove is formed by a method using a forming die (for example, forging, casting, sintering). Is defined as a minute angle corresponding to a draft angle set when a transmission groove, that is, a square groove is molded.

  According to the first feature of the present invention, the wave-shaped annular transmission grooves of the pair of transmission members that are opposed to each other by providing the speed change mechanism are constituted by square grooves having a U-shaped cross section, while both transmissions A plurality of rolling elements, which are interposed at the intersections of the grooves and change transmission between the two transmission members, are composed of rollers that can extend over both transmission grooves and roll on the inner side surfaces of both transmission grooves, Since the outer peripheral surface of the axially intermediate portion of each roller is constituted by a cylindrical surface that is fitted and supported in the holding hole of the holding member so as to be able to rotate and slide, the contact angle of the roller (rolling element) with respect to each transmission groove is Since it can be set sufficiently large at or near 90 °, the thrust load generated between the transmission groove and the roller can be reduced to zero or greatly reduced, so that the transmission efficiency of the transmission mechanism can be effectively increased. Furthermore, since the distance between the two transmission members can be freely set by selecting the axial length of the roller, a sufficient installation space for the holding member can be secured between the two transmission members.

  In addition, the outer peripheral surface of each roller smoothly decreases from the contact portion toward the both end surfaces in the region from each contact portion to the inner end surfaces of both transmission grooves in the axial direction. Because of the curved shape, it is possible to avoid a local load increase due to edge contact between the roller and the transmission groove even if the roller is slightly inclined during transmission. Rolling can be ensured to contribute to further improvement of transmission efficiency and further improvement of durability of rollers and transmission grooves.

  According to the second feature, the inner peripheral surface of the holding hole of the holding member that fits and supports the intermediate portion in the axial direction of each roller has a cross-sectional shape including the center line of the holding hole protruding toward the center line side. Therefore, even if the roller is slightly inclined during transmission, it is possible to avoid an increase in local load due to edge contact between the roller and the holding hole. Rolling can be ensured, and it can contribute to the further improvement of transmission efficiency and the durability improvement of a roller and a holding member.

  Further, according to the third feature, the opposing inner side surfaces of the respective transmission grooves are expanded so as to expand toward the open surface side of the groove with a predetermined minute taper angle. While significantly reducing the thrust load generated in the meantime, positioning in the thrust direction with respect to the transmission groove of the roller can be performed accurately, which can contribute to prevention of axial backlash and vibration of the roller. In addition, since the cross-sectional shape of each transmission groove can be formed in a substantially U-shape, the forming accuracy of each transmission groove (and hence the accuracy of the contact angle between the transmission groove and the roller) can be easily increased. The load can be stabilized.

1 is a longitudinal front view of a transmission device (differential device) according to a first embodiment of the present invention. An exploded perspective view of a differential mechanism in the differential device 3-3 sectional view of FIG. Sectional view taken along line 4-4 in FIG. Sectional view along line 5-5 in FIG. 1 is an enlarged cross-sectional view taken along the arrow 6 in FIG. FIG. 6 is a sectional view corresponding to FIG. 6 showing a second embodiment of the present invention.

  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 to 5 will be described. In FIG. 1, a differential device D as a transmission device is housed in a transmission case 1 of an automobile together with a transmission.

  In the differential device D, the left and right drive axles S1, S2 (in which the rotation of the ring gear Cg that rotates in conjunction with the output side of the transmission device is arranged on the central axis of the differential device D, that is, the first axis X1, are relatively rotatable. That is, the first and second drive shafts) are distributed while allowing differential rotation between the drive axles S1 and S2. The drive axles S1, S2 and the transmission case 1 are sealed with seal members 4, 4 '.

  The bottom of the mission case 1 is configured as an oil pan (not shown) that can store a predetermined amount of lubricating oil. The stored lubricating oil in the oil pan is vigorously stirred by rotating a rotating portion in the mission case 1, for example, a differential case C described later, and scattered widely in the internal space of the case 1, and the scattered lubricating oil makes the case Each part in 1, that is, a lubricated part can be lubricated. In addition to (or instead of) the above-described lubrication structure, the lubricating oil pumped by pump means such as an oil pump may be forcibly fed to each part in the mission case 1.

  The differential device D includes a differential case C as a transmission case that is rotatably supported by the transmission case 1 around the first axis X1, and a differential mechanism 3 described later that is housed in the differential case C. The differential case C includes a ring gear Cg made of a helical gear having oblique teeth Cga provided on the outer periphery of a short cylindrical gear body, and a pair of left and right first and first pairs whose outer peripheral ends are joined to both axial ends of the ring gear Cg. 2 side wall parts Ca and Cb. At least one of the side wall portions Ca and Cb is provided with a drain hole (not shown) capable of appropriately discharging excess lubricating oil in the differential case C by centrifugal force or the like in the vicinity of the outer peripheral end thereof.

  The first and second side wall portions Ca and Cb integrally have cylindrical first and second hubs HB1 and HB2 arranged on the first axis X1 at their inner peripheral end portions, respectively. The outer peripheral portions of HB1 and HB2 are rotatably supported by the mission case 1 via bearings 2 and 2 '. The first and second drive axles S1 and S2 are fitted and supported on the inner peripheral portions of the first and second hubs HB1 and HB2 so as to be rotatable about the first axis X1, respectively. At least one of the fitting surfaces (in the illustrated example, the inner peripheral surfaces of the hubs HB1 and HB2) includes at least the hubs HB1 and HB2 and the drive axle S1, when the automobile is moving forward (ie, when the drive axles S1 and S2 are rotating forward). Along with the relative rotation with S2, first and second spiral grooves 18 and 19 for drawing the scattered lubricating oil in the mission case 1 into the differential case C are formed. The outer ends of the spiral grooves 18 and 19 are opened in the mission case 1 and the inner ends thereof are opened in the differential case C, respectively.

  In the present embodiment, the spiral grooves 18 and 19 are exemplified as the lubricating oil supply means for supplying the lubricating oil in the mission case 1 into the differential case C. In addition to the spiral grooves 18 and 19, (Or instead), as another lubricating oil supply means, for example, an oil passage (not shown) provided with lubricating oil pumped by pump means such as an oil pump in the drive axles S1, S2 and / or the differential case C It may be supplied into the differential case C via Alternatively, as yet another lubricating oil supply means, a through hole that directly communicates the inside and the outside may be formed in at least one of the side wall portions Ca and Cb of the differential case C. The spiral grooves 18 and 19 may be formed on the outer peripheral surfaces of the drive axles S1 and S2.

  Next, the structure of the differential mechanism 3 in the differential case C will be described. The differential mechanism 3 is provided integrally with the first side wall portion Ca and can be rotated around the first axis X1 and is spline-fitted 16 to the first drive axle S1 to be coupled to the first axis X1. A hollow main shaft portion 6j that integrally includes a cylindrical first spline boss SB1 (that is, a first output boss) that can rotate around, and a second axis X2 that is eccentric from the first axis X1 by a predetermined eccentricity e. An eccentric rotating member 6 in which an eccentric shaft portion 6e serving as an axis is coupled and integrated, and one side portion is disposed opposite to the first transmission member 5, and the eccentric shaft portion 6e is rotatable via a bearing 7 formed of a ball bearing. An annular second transmission member 8 to be supported and a circle that is disposed opposite to the other side of the second transmission member 8 and is spline-fitted 17 to the second drive axle S2 so as to be rotatable about the first axis X1. An annular third transmission member 9 and first and second transmission members 5, A first transmission mechanism T1 which transmit the torque while shifting between, and a second transmission mechanism T2 which transmit the torque while shifting between the second and third transmission members 8,9.

  Thus, the second transmission member 8 is rotatably supported around the second axis X2 by the second transmission member 8 being rotatably supported on the eccentric shaft portion 6e of the eccentric rotation member 6 that rotates about the first axis X1. Can revolve around the first axis X1 relative to the main axis 6j while rotating around the second axis X2 relative to the eccentric axis 6e of the eccentric rotating member 6 around the first axis X1. .

  Further, the second transmission member 8 has a ring plate-like first half 8a that is rotatably supported by the eccentric shaft portion 6e of the eccentric rotating member 6 via a bearing 7, and an interval between the first half 8a. And a ring-plate-shaped second half body 8b facing each other and a basically cylindrical connecting member 8c for integrally connecting the two half bodies 8a and 8b. In particular, in the present embodiment, the first half 8a and the second half 8b are respectively fitted in the inner peripheral surfaces of the one end and the other end of the connecting member 8c, and the fitting portions are welded and caulked. It is fixed by suitable fixing means such as. The first transmission mechanism T1 is disposed between the opposing surfaces of the first half 8a and the first transmission member 5, and the second transmission mechanism T1 is disposed between the opposing surfaces of the second half 8b and the third transmission member 9. A transmission mechanism T2 is provided.

  The connecting member 8c is provided with a plurality of first oil circulation holes 11 that communicate between the internal space IC of the differential case C and the hollow portion SP of the second transmission member 8 at equal intervals in the circumferential direction. Lubricating oil scattered in the internal space IC can be introduced into the hollow portion SP through the first oil circulation hole 11. Further, the second half body 8b is formed with a second oil circulation hole 12 that communicates the hollow portion SP with the inner peripheral side of the second transmission mechanism T2 in a circular shape with the second axis X2 as the center.

  The third transmission member 9 is a main shaft that integrally includes a cylindrical second spline boss SB2 (that is, a second output boss) that is spline-fitted 17 to the second drive axle S2 and is rotatable about the first axis X1. A portion 9j and a circular ring plate portion 9c concentrically connected to the inner end portion of the main shaft portion 9j and facing the second half 8b are coupled and integrated. The spline fitting 17 part is provided with a partial tooth portion in the circumferential direction, and the partial tooth portion is pulled from the transmission case 1 into the differential case C by the pulling action of the second spiral groove 19. The lubricating oil can be efficiently guided to the inner peripheral side of the second retainer H2, which will be described later, and to the hollow portion SP of the second transmission member 8.

  A first thrust washer TH1 that allows relative rotation between the inner side surface of the first side wall portion Ca of the differential case C and the eccentric rotating member 6 is interposed between the inner surface and the first spiral groove. An oil passage 41 is formed to communicate the inner end opening (i.e., outlet) of 18 with the inner peripheral side of the first transmission mechanism T1 via the back surface of the first thrust washer TH1. Lubricating oil drawn into the differential case C from the transmission case 1 by the pulling action of the first spiral groove 18 flows into the oil passage 41, and the flowing lubricating oil flows into the inner peripheral side of the first transmission mechanism T1 and the bearing. 7 is supplied.

  Further, a second thrust washer TH2 that allows relative rotation between the inner surface of the second side wall portion Cb of the differential case C and the outer surface of the third transmission member 9 is interposed. In the second thrust washer TH2, the lubricating oil drawn into the differential case C from the transmission case 1 by the drawing action of the second spiral groove 19 is oil between the third transmission member 9 and the second side wall Cb. Supplied through line 45.

  Further, the differential mechanism 3 is opposite in phase to the eccentric shaft portion 6e of the eccentric rotating member 6 and the total center of gravity G of the second transmission member 8 across the first axis X1, and larger than the rotational radius of the total center of gravity G. And a balance weight W that is attached to the main shaft portion 6j of the eccentric rotating member 6 so as not to be relatively rotatable. This balance weight W is comprised from the cyclic | annular base part Wm fixed to the main axis | shaft part 6j with the clip 10, and the weight part Ww fixed to the circumferential direction specific area | region of the cyclic | annular base part Wm. The hollow portion SP of the second transmission member 8 is used as a storage space for the balance weight W.

  As shown in FIGS. 1 to 3, the first transmission member 5 has a waveform centered on the first axis X <b> 1 on the inner surface facing the one side portion (first half 8 a) of the second transmission member 8. An annular first transmission groove 21 is formed, and the first transmission groove 21 extends in the circumferential direction along a hypotrochoid curve having a virtual circle centered on the first axis X1 in the illustrated example. On the other hand, a corrugated annular second transmission groove 22 centering on the second axis X2 is formed on one side portion (first half 8a) of the second transmission member 8 facing the first transmission member 5. . 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 smaller than the wave number of the first transmission groove 21. It has a wave number and intersects the first transmission groove 21 at a plurality of locations.

  The first transmission groove 21 and the second transmission groove 22 are constituted by square grooves having a U-shaped cross section as shown in FIGS. Moreover, the opposing inner side surfaces of the respective transmission grooves 21 and 22 are expanded in a pre-expanded manner toward the open surface side of the groove with a predetermined minute taper angle α. In the case of this embodiment, since the first transmission member 5 (first side wall portion Ca) and the second transmission member 8 (first and second half bodies 8a and 8b) are forged, the predetermined minute taper is used. The angle α corresponds to a minute angle corresponding to a draft angle set when the angular grooves 21 and 22 are molded during the forging process, and preferably 1 ° to 3 °. It is arbitrarily set within the range.

  A plurality of first rollers 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. Each first roller 23 extends in a substantially cylindrical shape so as to straddle between the first and second transmission grooves 21, 22, and both axial end portions 23 a, 23 b thereof are in the transmission grooves 21, 22. Each is received and can roll on the inner surfaces of both transmission grooves 21 and 22.

  Between the opposing surfaces of the first transmission member 5 and the second transmission member 8 (first half 8a), a circular ring plate-shaped first retainer H1 as a first holding member is interposed. This 1st retainer H1 is engaged with both the transmission grooves 21 and 22 of the some 1st roller 23 (namely, axial direction both ends 23a and 23b) in the cross | intersection part of the 1st, 2nd transmission grooves 21 and 22 mutually. In order to maintain the state, a plurality of first holding holes 31 having a circular cross section that hold each of the axially intermediate portions 23m of the plurality of first rollers 23 rotatably are arranged at equal intervals in the circumferential direction of the retainer H1. Have.

  The outer peripheral surface of each of the first rollers 23 has the outer diameter particularly in the region extending from each contact portion t to the inner side surface of each of the first and second transmission grooves 21 and 22 to both axial end surfaces f. It has a curved surface shape that is smoothly reduced from the contact portion t toward both end faces f. As this curved surface shape, a chamfered surface having a longitudinal cross-sectional arc shape as illustrated in FIG. 6, that is, a chamfer surface r is employed in this embodiment, and both end surfaces f of each roller 23 surrounded by the chamfer surface r are used. The central portion is formed on a flat surface orthogonal to the axis of each roller 23. Note that the chamfer surface r in the illustrated example is formed as a curved surface whose curvature increases as the end surface f approaches.

  Moreover, the outer peripheral surface of the axial direction intermediate part 23m of each 1st roller 23 is comprised by the cylindrical surface fitted and supported by the holding hole 31 of the 1st retainer H1 so that rotation sliding is possible. The inner peripheral surface of the holding hole 31 of the first retainer H1 that fits and supports the outer peripheral surface of the axial intermediate portion 23m of the first roller 23 has a cross-sectional shape including the center line of the holding hole 31. As shown in FIG. 6, it is formed in a convex arc shape on the center line side.

  As shown in FIGS. 1, 2, and 4, a corrugated annular third transmission groove 24 centering on the second axis X <b> 2 is formed on the other side (second half 8 b) of the second transmission member 8. In the illustrated example, the third transmission groove 24 extends in the circumferential direction along a hypotrochoidal curve having a virtual circle centered on the second axis X2 as a base circle. On the other hand, on the surface of the third transmission member 9 facing the second transmission member 8, that is, on the inner surface of the ring plate portion 9c, a corrugated fourth transmission groove 25 centered on the first axis X1 is formed. In the illustrated example, the fourth transmission groove 25 extends in the circumferential direction along an epitrochoidal curve having a virtual circle centered on the first axis X1 as a base circle, and is smaller than the wave number of the third transmission groove 24. It has a wave number and intersects with the third transmission groove 24 at a plurality of locations. The third and fourth transmission grooves 24 and 25 are also formed by square grooves having a U-shaped cross section similar to the first and second transmission grooves 21 and 22 described above. The inner surfaces facing each other are also expanded in a pre-expanded manner toward the open surface side of the groove with a predetermined small taper angle α as described above.

  A plurality of second rollers 26 as second rolling elements are interposed at intersections (that is, overlapping portions) of the third transmission groove 24 and the fourth transmission groove 25. Each second roller 26 extends in a substantially cylindrical shape so as to straddle between the third and fourth transmission grooves 24 and 25, and both axial ends thereof are received in the transmission grooves 24 and 25, respectively. And the inner side surfaces of both the transmission grooves 24 and 25 can roll freely.

  Between the opposing surfaces of the second transmission member 8 (second half 8b) and the third transmission member 9, a circular ring plate-like second retainer H2 as a second holding member is interposed. The second retainer H2 has a plurality of second rollers 26 so that the plurality of second rollers 26 can be engaged with the transmission grooves 24, 25 at the intersections of the third and fourth transmission grooves 24, 25. A plurality of second holding holes 32 having a circular cross section for rotatably holding the axial intermediate portion 23m of the second roller 26 are provided at equal intervals in the circumferential direction of the retainer H2. The shape and structure of each second roller 26 is the same as that of the first roller 23 described above, and the inner peripheral surface shape of the second shape retaining hole 32 is the same as the inner peripheral surface shape of the first shape retaining hole 31. It is.

  In the present embodiment, the first transmission member 5 (first side wall portion Ca) and the second transmission member 8 (first and second half bodies 8a and 8b) each having the wave-shaped annular transmission grooves 21, 22, 24, and 25. ) And the third transmission member 9 are forged. However, they may be formed by other forming methods using a forming die (for example, casting, sintering, etc.).

  In the present embodiment, the trochoidal coefficients of the first and second transmission grooves 21 and 22 and the trochoidal coefficients of the third and fourth transmission grooves 24 and 25 are set to different values.

In the present embodiment described above, 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. The first to fourth transmission grooves 21, 22, 24, and 25 are formed so that the following expression is established.
(Z1 / Z2) × (Z3 / Z4) = 2
Desirably, Z1 = 8, Z2 = 6, Z3 = 6, Z4 = 4, or Z1 = 6, Z2 = 4, Z3 = 8, and Z4 = 6 as shown in the illustrated example.

  In the illustrated example, the eight-wave first transmission groove 21 and the six-wave second transmission groove 22 intersect at seven locations, and seven first rollers 23 are formed at the seven intersections (overlapping portions). The six-wave third transmission groove 24 and the four-wave fourth transmission groove 25 intersect at five locations, and five second rollers 26 are interposed at the five intersecting portions (overlapping portions). Be dressed.

  Thus, the first transmission groove 21, the second transmission groove 22, and the first roller 23 cooperate with each other so that torque can be transmitted while shifting between the first transmission member 5 and the second transmission member 8. The mechanism T1 is configured, and the third transmission groove 24, the fourth transmission groove 25, and the second roller 26 cooperate with each other to transmit torque while shifting between the second transmission member 8 and the third transmission member 9. A second transmission mechanism T2 is configured.

  In the present embodiment described above, the first and second speed change mechanisms T1 and T2 constitute the speed change mechanism of the present invention. Particularly in the first speed change mechanism T1, the first transmission member 5 constitutes one transmission member, the second transmission member 8 constitutes the other transmission member, and the first transmission groove 21 constitutes one transmission groove. And the second transmission groove 22 constitutes the other transmission groove. Particularly in the second transmission mechanism T2, the third transmission member 9 constitutes one transmission member, the second transmission member 8 constitutes the other transmission member, and the fourth transmission groove 25 serves as one transmission groove. In addition, the third transmission groove 24 constitutes the other transmission groove.

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

  Now, for example, in a state where the eccentric rotary member 6 (and hence the eccentric shaft portion 6e) is fixed by fixing the right first drive axle S1, the ring gear Cg is driven by the power from the engine, and the differential case C and therefore the first When the transmission member 5 is rotated around the first axis X 1, the eight-wave first transmission groove 21 of the first transmission member 5 passes through the six-wave second transmission groove 22 of the second transmission member 8 via the first roller 23. Therefore, the first transmission member 5 drives the second transmission member 8 with a speed increasing ratio of 8/6. According to the rotation of the second transmission member 8, the six-wave third transmission groove 24 of the second transmission member 8 replaces the four-wave fourth transmission groove 25 of the ring plate portion 9 c of the third transmission member 9. Since the second roller 26 is driven, 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 the state where the third transmission member 9 is fixed by fixing the left second driving axle S2, the rotational driving force of the first transmission member 5 Due to the driving reaction force of the second transmission member 8 against the stationary third transmission member 9, the second transmission member 8 rotates while rotating about the eccentric shaft portion 6 e (second axis X 2) of the eccentric rotation member 6. Revolving around one axis line X1 drives the eccentric shaft portion 6e around the first axis line 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.

  At that time, Z1 = 8, Z2 = 6, Z3 = 6, Z4 = 4, or Z1 = 6, Z2 = 4, Z3 = 8, Z4 = 6 to ensure the differential function. Simplification of the eaves structure can be achieved.

  By the way, in this differential device D, the rotational torque of the first transmission member 5 is applied to the second transmission member 8 via the first transmission groove 21, the plurality of first rollers 23 and the second transmission groove 22, and to the second transmission member 2. Since the rotational torque of the transmission member 8 is transmitted to the third transmission member 9 through the third transmission groove 24, the plurality of second rollers 26, and the fourth transmission groove 25, respectively, the first transmission member 5 and the second transmission member are transmitted. Between each of the member 8, the second transmission member 8 and the third transmission member 9, torque transmission is performed in a distributed manner at a plurality of locations where the first and second rollers 23 and 26 are present. It is possible to increase the strength and weight of each transmission element such as the three transmission members 5, 8, 9 and the first and second rollers 23, 26.

  Further, the differential device D can flatten the first to third transmission members 5, 8, and 9 as much as possible in the axial direction, and the relative relationship between the first and second transmission members 5, 8 is also possible. The first transmission mechanism T1 between the facing surfaces and the second transmission mechanism T2 between the opposing surfaces of the second and third transmission members 8 and 9 are separated from the first transmission member 5 when the eccentric rotating member 6 is fixed. The third transmission member 9 is configured to be driven with a double speed increasing ratio, so that a differential device D that can be easily flattened in the axial direction can be obtained.

  During the operation of the differential device D, the stored lubricating oil at the bottom of the transmission case 1 is stirred by the differential case C and the like and scattered in the transmission case 1 over a wide range as described above, and a part of the scattered lubricating oil is The differential case C is actively supplied from both sides by the pulling action of the first and second spiral grooves 18 and 19 accompanying the relative rotation between the hubs HB1 and HB2 of the differential case C and the drive axles S1 and S2. Then, each movable part of the differential mechanism 3 including the first and second transmission mechanisms T1 and T2 is lubricated by the supplied lubricating oil.

  Further, in particular, in the present embodiment, in the first transmission mechanism T1, of the pair of transmission members 5 and 8 facing each other, one transmission member (that is, the first transmission member 5) and the other transmission member (that is, the second transmission member). The first and second transmission grooves 21 and 22 forming the corrugated annular shape of the first half body 8a) of FIG. 8 are each constituted by a square groove having a U-shaped cross section, and are interposed at the intersection of the two transmission grooves 21 and 22. A plurality of first rolling elements that are mounted and transmit gears between the two transmission members 5 and 8 can extend across the two transmission grooves 21 and 22 and roll on the inner surfaces of the two transmission grooves 21 and 22. Further, the outer peripheral surface of the intermediate intermediate portion 23m of each roller 23 is formed by a cylindrical surface that is fitted and supported in the holding hole 31 of the first retainer H1 so as to be able to rotate and slide. ing. Therefore, the contact angle β of the first roller 23 with respect to each of the transmission grooves 21 and 22 can be set sufficiently large at or near 90 °. As shown in FIG. 6, the contact angle β is defined as a normal L passing through the contact portion t between the outer peripheral surface of the first roller 23 and the inner surfaces of the transmission grooves 21 and 22, and the transmission load at the contact portion t. The angle formed by the thrust direction component force (i.e., thrust load) acting direction, for example, on the inner surface of the transmission grooves 21 and 22, a predetermined small taper angle α corresponding to the draft at the time of molding as described above. Is approximately (90 ° −α), and the taper angle α is zero, that is, 90 ° when there is no draft as in machining the transmission grooves 21 and 22 by machining. Become.

  Thus, by making the contact angle β of the first roller 23 with respect to the transmission grooves 21 and 22 sufficiently large, the thrust load generated between the transmission grooves 21 and 22 and the roller 23 can be reduced to zero or greatly reduced. Therefore, the transmission efficiency of the first transmission mechanism T1 is effectively increased, and the thrust receiving portion on the back side of the first transmission member 5 (in this embodiment, the first side wall portion Ca of the differential case C integrated with the first transmission member 5). ) Can be reduced, and the differential device D can be reduced in weight and durability. Further, since the opposing distance between the first and second transmission members 5 and 8 can be freely set according to the selection of the axial length of the first roller 23, the first retainer is provided between the transmission members 5 and 8. A sufficient installation space for H1 can be secured.

  In addition, in the present embodiment, the outer peripheral surface of each roller 23 is the outer surface of each first roller 23 in the region from each contact portion t to the inner surface of both transmission grooves 21 and 22 to both axial end surfaces f. Since it is formed in a curved surface shape (chamfer surface r) in which the diameter is smoothly reduced from the contact portion t toward the both end surfaces f, even if a slight inclination occurs in the first roller 23 during transmission, A local load increase due to edge contact between the one roller 23 and the first and second transmission grooves 21 and 22 can be avoided. As a result, smooth rolling of the first roller 23 is ensured, so that the transmission efficiency of the first transmission mechanism T1 is further improved and the durability of the first roller 23 and the transmission grooves 21 and 22 is further improved. It is done.

  Furthermore, in the present embodiment, the inner peripheral surface of the holding hole 31 in the first retainer H1 that fits and supports the intermediate portion 23m in the axial direction of the first roller 23 includes a center line of the holding hole 31 (FIG. 6). Is formed in a circular arc shape convex toward the center line side. For this reason, even if a slight inclination occurs in the first roller 23 during transmission, it is possible to avoid a local load increase due to edge contact between the first roller 23 and the holding hole 31. The smoother rolling of the first transmission mechanism T1 is further ensured, and the transmission efficiency of the first transmission mechanism T1 is further improved, and the durability of the first roller 23 and the first retainer H1 is improved.

  Furthermore, in the present embodiment, the opposing inner surfaces of the first and second transmission grooves 21 and 22 are expanded in a pre-expanded manner toward the groove opening surface side with a predetermined minute taper angle α. While the thrust load generated between the first roller 23 and the transmission grooves 21 and 22 is greatly reduced, the first roller 23 can be accurately positioned in the thrust direction with respect to the transmission grooves 21 and 22. This is effective in preventing the axial play of the 23 and vibration. Moreover, since the cross-sectional shape of each transmission groove 21, 22 can be formed in a substantially U-shape, the forming accuracy of each transmission groove 21, 22 (and thus the contact angle β between the transmission groove 21, 22 and the first roller 23) Accuracy) is easily increased, and the thrust load is stabilized.

  Also, in the second transmission mechanism T2, of the pair of opposing transmission members 9, 8, one transmission member (that is, the third transmission member 9) and the other transmission member (that is, the second transmission member 8 is the second transmission member 8). The wavy annular third and fourth transmission grooves 24, 25 of the half body 8 b) are constituted by square grooves having a U-shaped cross section, and are interposed at the intersections of both transmission grooves 24, 25, so that both transmission members A plurality of second rolling elements that transmit gears between 9 and 8 extend across both transmission grooves 24 and 25 and can roll on the inner surfaces of both transmission grooves 24 and 25. 26, and the outer peripheral surface of the axial intermediate portion 26m of each roller 26 is formed of a cylindrical surface that is fitted and supported in the holding hole 32 of the second retainer H2 so as to be able to rotate and slide. The shapes and structures of the second roller 26, the third and fourth transmission grooves 24 and 25, and the holding hole 32 of the second retainer H2 are the same as the first roller 23, the first and second transmissions in the first transmission mechanism T1. Since it is the same as that of the holding holes 31 of the grooves 21 and 22 and the first retainer H1, the second transmission mechanism T2 can exhibit the same effects as the first transmission mechanism T1 with respect to its shape and structure. is there.

  Therefore, since the contact angle β of the second roller 26 with respect to the third and fourth transmission grooves 24 and 25 can be set sufficiently large, the thrust load generated between the transmission grooves 24 and 25 and the rollers 26 is made zero, or The transmission efficiency of the second transmission mechanism T2 can be effectively increased, and the load on the thrust receiving portion on the back side of the third transmission member 9 (in this embodiment, the second side wall portion Cb of the differential case C) can be reduced. Can be reduced. In addition, since the distance between the second and third transmission members 8 and 9 can be freely set according to the selection of the axial length of the second roller 26, the second retainer is provided between the two transmission members 8 and 9. A sufficient installation space for H2 can be secured. With respect to other functions and effects, the second transmission mechanism T2 can achieve the same functions and effects as the above-described functions and effects of the first transmission mechanism T1.

  Next, a second embodiment of the present invention will be described with reference to FIG. Also in the second embodiment, the outer peripheral surfaces of the first and second rollers 23, 26 are particularly axially opposite from the contact portions t of the rollers 23, 26 with respect to the transmission grooves 21, 22, 24, 25 on both sides. In a region reaching the surface f, a curved surface shape is formed in which the outer diameter is smoothly reduced from the contact portion t toward both end surfaces f. However, in the second embodiment, as the curved surface shape, as illustrated in FIG. 7, a crowning surface r ′ that gradually increases toward the center of the end surfaces f of the rollers 23 and 26 is employed. Therefore, the entire end surface f including the central portion is formed as a convex curved surface.

  Since other configurations are the same as those in the first embodiment, the same reference numerals as those in the first embodiment are given to the respective components, and further specific description is omitted. In the second embodiment, basically the same effects as the first embodiment can be achieved.

  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 above embodiment, the differential device D is exemplified as the transmission device, and the power input from the power source to the differential case C (first transmission member 5) is transmitted via the first and second transmission mechanisms T1 and T2. Although the first and second drive axles S1 and S2 (drive shafts) are distributed while allowing differential rotation, the present invention can be implemented in various transmission devices other than the differential gear. is there. For example, the casing corresponding to the differential case C of the above embodiment is a fixed transmission case, one of the first and second drive axles S1, S2 is an input shaft, and one of the other is an output shaft. The differential device D of the embodiment can be diverted as a transmission (decelerator or speed increaser) that can change (decelerate or increase speed) the rotational torque input to the input shaft and transmit it to the output shaft. In such a case, such a transmission (reduction gear or speed increaser) is the transmission device of the present invention. In this case, the transmission may be a transmission for a vehicle or a transmission for various mechanical devices other than the vehicle.

  Moreover, in the said embodiment, although the differential device D as a transmission device is accommodated in the vehicle-mounted mission case 1 for motor vehicles, the differential device D is not limited to the differential device for motor vehicles. It can also be implemented as a differential for various mechanical devices.

  In the above embodiment, the differential device D as a transmission device is applied to the left and right wheel transmission systems to distribute power while allowing differential rotation to the left and right drive axles S1, S2. However, in the present invention, a differential device as a transmission device is applied to a front / rear wheel transmission system in a front / rear wheel drive vehicle to allow power to be driven while allowing differential rotation with respect to front and rear drive wheels. May be distributed.

  Moreover, although the 2nd transmission member 8 of the said embodiment was comprised from the 1st, 2nd half bodies 8a and 8b and the connection member 8c, the 2nd transmission member 8 is one surface of one plate-shaped member. Alternatively, the second transmission groove 22 may be provided, and the third transmission groove 24 may be provided on the other surface.

  Moreover, in the said embodiment, although each transmission groove 21,22; 24,25 of 1st, 2nd transmission mechanism T1, T2 is made into the corrugated cyclic | annular wave groove along a trochoid curve, these transmission grooves are embodiment. For example, it may be a corrugated annular wave groove along a cycloid curve, or alternatively, the first transmission groove 21 (or the third transmission groove 24) is a wave groove along an epitrochoid curve, The second transmission groove 22 (or the fourth transmission groove 25) may be a wave groove along the hypotrochoid curve.

  In the above-described embodiment, the eccentric rotating member 6 and the third transmission member 9 are connected to the drive axles S1 and S2 supported by the differential case C (spline fittings 16 and 17), and the drive axles S1 and S2 are interposed therebetween. In the present invention, the eccentric rotation member 6 and the third transmission member 9 may be directly supported by the differential case C.

  In the above-described embodiment, the first and second retainers H1 and H2 as the holding members are each constituted by an annular ring having inner and outer peripheral surfaces each having a perfect circle. The shape of the second retainer) is not limited to the above-described embodiment, and may be any annular ring body that can hold each of the plurality of first and second rollers 23 and 26 as rolling elements at regular intervals. For example, an elliptical ring plate or an annular ring plate curved in a waveform may be used.

  In the above-described embodiment, the transmission device includes two transmission mechanisms (that is, the first and second transmission mechanisms T1 and T2). However, the present invention provides a transmission device including one or more transmission mechanisms. Is also applicable. In addition, the present invention can be applied to at least one speed change mechanism among a plurality of speed change mechanisms included in the transmission, for example, one of the first speed change mechanism T1 and the second speed change mechanism T2 of the embodiment. The present invention may be applied only to the speed change mechanism.

C ・ ・ ・ ・ ・ ・ Differential case (Transmission case)
D ・ ・ ・ ・ ・ ・ Differential device (Transmission device)
H1, H2 ··· First and second retainers (holding members)
T1, T2, ... 1st and 2nd transmission mechanism (transmission mechanism)
X1, X2 ··· First and second axis f ··· End surface t of first and second rollers ··· Contact portion α of first and second rollers with inner surface of transmission groove α・ ・ ・ ・ ・ ・ Taper angle 5 on the inner surface of the transmission groove ・ ・ ・ ・ ・ ・ First transmission member (One transmission member)
6... Eccentric rotating member 8... 2nd transmission member (the other transmission member)
9 .... Third transmission member (One transmission member)
21, 25 .. 1st and 4th transmission groove (one transmission groove)
22, 24 ··· 2nd and 3rd transmission groove (the other transmission groove)
23, 26 .. First and second rollers (rolling elements)
23a, 23b,... Both end portions 23m, 26m of the first roller, axially intermediate portions 31, 32,.

Claims (3)

A transmission mechanism (T1) provided between a pair of transmission members (5, 9; 8) facing each other and both transmission members (5, 9; 8) and capable of transmitting torque while shifting between the transmission members (5, 9; 8). , T2), one transmission member (5, 9) having the first axis (X1) as the central axis, and the other transmission member (8) decentered from the first axis (X1). Revolving around the first axis (X1) while rotating around the two axes (X2),
The pair of transmission members (5, 9; 8) have transmission grooves (21, 22, 25, 24) on opposite surfaces of both of them,
The transmission mechanism (T1, T2) is provided on the one transmission member (5, 9) and has one of the transmission grooves (21, 25) having a corrugated ring centered on the first axis (X1); The other transmission groove (22, 22) provided on the other transmission member (8) has a corrugated annular shape around the second axis (X2) and has a wave number different from that of the one transmission groove (21, 25). 24), and the one transmission groove (21, 25) and the other transmission groove (22, 24) are interposed at a plurality of intersections, and both the transmission grooves (21, 22, 25, 24) A plurality of rolling elements (23, 26) that perform transmission transmission between the two transmission members (5, 9; 8) while rolling, and hold the rolling elements (23, 26) at intervals in the circumferential direction. A holding member having a holding hole (31, 32) and interposed between the two transmission members (5, 9, 8) A transmission device comprising a 1, H2) and,
While both the transmission grooves (21, 22, 25, 24) are formed by square grooves having a U-shaped cross section, the rolling element straddles between the transmission grooves (21, 22, 25, 24). And both ends (23a, 23b) are composed of rollers (23, 26) that can roll on the inner surfaces of both transmission grooves (21, 22, 25, 24), respectively.
Each roller (23, 26) is in a region from each contact portion (t) to the inner side surface of both the transmission grooves (21, 22, 25, 24) to both end surfaces (f) in the axial direction. , 26) has a curved shape in which the outer diameter is smoothly reduced from the contact portion (t) toward the both end faces (f),
The outer peripheral surfaces of the axially intermediate portions (23m, 26m) of the rollers (23, 26) are fitted and supported in the holding holes (31, 32) of the holding members (H1, H2) so as to be able to rotate and slide. A transmission device comprising a cylindrical surface.   The inner peripheral surface of the holding hole (31, 32) that fits and supports the axial intermediate part (23m, 26m) of each roller (23, 26) is the center line of the holding hole (31, 32). 2. The transmission device according to claim 1, wherein the cross-sectional shape including a circular arc is convex toward the center line.   The opposed inner surfaces of each of the transmission grooves (21, 22, 25, 24) are widened in a pre-expanded manner toward the open surface side of the groove with a predetermined minute taper angle (α). The transmission device according to claim 1 or 2.

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