JP2014009793A - Power transmission device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To compensate the influence of torsion of an output shaft in a power transmission device in which a plurality of transmission units are axially arranged parallel to one another and to reduce torque fluctuation.SOLUTION: In a power transmission device for a vehicle, an eccentric disk of a transmission unit rotates in an eccentric manner when an input shaft rotates which is connected to a driving source, and an output shaft 13 intermittently rotates via a one-way clutch 36 to which one end of a connecting rod 33 is connected when the connecting rod 33 reciprocates of which the other end is connected to the eccentric disk. The influence of torsion of the output shaft 13 causes an amount of torque transmission of the one-way clutch 36 on one shaft end side of the output shaft 13 outputting driving force to be increased and the amount of torque transmission of the one-way clutch 36 on the other shaft end side of the output shaft 13 to be decreased. However, an angle of inclination of inclined surface 39a on an inner member 39 that faces an inner peripheral surface on an outer member 38 of the one-way clutch 36 via a roller 41 is set to be gradually larger from the one shaft end side to the other shaft end side of the output shaft 13.

Description

  The present invention relates to a vehicular power transmission device in which a plurality of transmission units that shift rotation of an input shaft connected to a drive source and transmit the rotation to an output shaft are juxtaposed in the axial direction between the input shaft and the output shaft.

  Such a vehicle power transmission device is known from Patent Document 1 below. This vehicle power transmission device includes a plurality of transmission units arranged in parallel in the axial direction, and each transmission unit is connected via a connecting rod and a one-way clutch that reciprocally move an input shaft and an output shaft. When the rod moves in one direction, the one-way clutch is engaged, and when the connecting rod moves in the other direction, the one-way clutch disengages to intermittently transmit the rotation of the input shaft to the output shaft. The transmission units alternately transmit driving force with a phase difference.

Special table 2003-530519 gazette

  By the way, in the conventional vehicle power transmission device, as shown in FIG. 11, driving force is inputted to the output shaft from the one-way clutches of the six transmission units # 1 to # 6 juxtaposed in the axial direction. Since the driving force is output to the differential gear connected to one axial end (# 6 side) of the shaft, the torsion angle of the output shaft due to the torque transmitted from the one-way clutch is connected to the driving wheel. It continuously changes so as to be minimum on one end side (# 6 side) close to the differential gear subjected to a rotational load and maximum on the other end side (# 1 side) far from the differential gear.

  As a result, the one-way clutch of the # 6 transmission unit at one end near the differential gear can efficiently transmit the driving force to the output shaft, while the one-way clutch of the # 1 transmission unit at the other end far from the differential gear outputs The driving force cannot be efficiently transmitted to the shaft. This is because if the twist angle of the output shaft increases, the one-way clutch inner member fixed to the output shaft rotates in the same direction as the outer member, so even if the outer member is rotated by the connecting rod, the one-way clutch is immediately This is because the torque transmission amount decreases without engaging.

  FIG. 10A shows torque transmission amounts of the six transmission units # 1 to # 6 of the vehicle power transmission device of the comparative example. Since the six transmission units are set so that the torque transmission phases of two adjacent transmission units overlap, the # 6 transmission unit with the maximum torque transmission amount and the second torque transmission amount from the maximum The sum of torque transmission amounts with the # 5 transmission unit is the maximum peak, and the sum of torque transmission amounts between the # 1 transmission unit with the smallest torque transmission amount and the second # 2 transmission unit with the smallest torque transmission amount is There is a problem that the torque peak ΔT becomes the minimum peak and the difference in torque fluctuation ΔT increases.

  The present invention has been made in view of the above circumstances, and an object thereof is to reduce the torque fluctuation by compensating for the effect of twisting of the output shaft of the vehicle power transmission device in which a plurality of transmission units are juxtaposed in the axial direction. .

  To achieve the above object, according to the first aspect of the present invention, a plurality of speed change units that change the speed of rotation of the input shaft connected to the drive source and transmit the rotation to the output shaft are provided to the input shaft and the output. One-way clutches that are juxtaposed in the axial direction between the shafts, and that each of the transmission units has a variable amount of eccentricity from the axis of the input shaft and rotates together with the input shaft and the output shaft And an output-side fulcrum provided on an outer member of the one-way clutch, and an input-side fulcrum and a connecting rod connected to both ends of the input-side fulcrum and reciprocatingly connected to the input-side of the plurality of transmission units. A vehicle power transmission device in which phases of fulcrums are different from each other and a driving force is output from one shaft end side of the output shaft, the one-way of the plurality of transmission units The latch includes an inner member that is fixed to the output shaft and has an inner surface formed with an inclined surface facing the inner peripheral surface of the outer member via a roller. The angle of inclination of the inclined surface is set to one of the shafts of the output shaft. A vehicular power transmission device is proposed which is set so as to increase sequentially from the end side to the other shaft end side.

  According to the invention described in claim 2, in addition to the configuration of claim 1, the phase of the input side fulcrum of the plurality of transmission units is changed from one shaft end side to the other shaft end of the input shaft. A vehicular power transmission device is proposed, which is sequentially changed to the side.

  The engine E of the embodiment corresponds to the drive source of the present invention, the eccentric disk 19 of the embodiment corresponds to the input side fulcrum of the present invention, and the pin 37 of the embodiment corresponds to the output side fulcrum of the present invention. Correspond.

  According to the configuration of the first aspect, when the input shaft connected to the drive source rotates, the eccentric disk of the transmission unit rotates eccentrically, and when the connecting rod connected at one end to the eccentric disk reciprocates, the other end of the connecting rod The output shaft rotates intermittently through the one-way clutch to which is connected. The output shaft rotates continuously by intermittently transmitting the driving force with a phase difference between the multiple speed change units, and the reciprocating stroke of the connecting rod changes when the eccentric amount of the eccentric disk with respect to the input shaft changes. The intermittent rotation angle of the output shaft changes to change the gear ratio. Due to the twist of the output shaft, the torque transmission amount of the one-way clutch of the transmission unit on one shaft end side of the output shaft that outputs driving force increases, and the one-way clutch of the transmission unit on the other shaft end side of the output shaft increases. Although the torque transmission amount is small, the inclination angle of the inclined surface of the inner member that faces the inner peripheral surface of the outer member of the one-way clutch via a roller is changed from one shaft end side of the output shaft to the other shaft end side. By setting so as to increase sequentially, the torque transmission amount of the one-way clutch of each transmission unit can be made uniform, and torque fluctuation can be reduced.

  According to the second aspect of the present invention, the phase of the input side fulcrum of the plurality of transmission units is sequentially changed from one shaft end side to the other shaft end side of the input shaft, so that it is randomly changed. Compared to the case, the torque fluctuation of the output shaft becomes larger, and therefore the effect of reducing the torque fluctuation of the output shaft of the present invention can be more effectively exhibited.

The whole view of a continuously variable transmission. The partially broken perspective view of the principal part of a continuously variable transmission. FIG. 3 is a sectional view taken along line 3-3 in FIG. 1. FIG. 4 is an enlarged view of part 4 of FIG. 3. FIG. 5 is a sectional view taken along line 5-5 of FIG. The figure which shows the shape of an eccentric disk. The figure which shows the relationship between the eccentric amount of an eccentric disk, and a gear ratio. The figure which shows the state of the eccentric disk in TD gear ratio and UD gear ratio. The figure which shows the one-way clutch of # 1 and # 6. Explanatory drawing of the torque fluctuation of an output shaft. Explanatory drawing of the twist angle of an output shaft.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  As shown in FIGS. 1 to 5, an input shaft 12 and an output shaft 13 are supported in parallel with each other on a pair of side walls 11 a and 11 b of a transmission case 11 of a continuously variable transmission T for an automobile. The rotation of the connected input shaft 12 is transmitted to the drive wheels via the six transmission units 14, the output shaft 13 and the differential gear D. In the present embodiment, the differential gear D is provided on one end side (right end side) of the output shaft 13 (see FIG. 1). A variable speed shaft 15 sharing an axis L with the input shaft 12 is fitted into the hollow formed input shaft 12 via seven needle bearings 16 so as to be relatively rotatable. Since the structure of the six transmission units 14 is substantially the same, the structure will be described below with one transmission unit 14 as a representative.

  The transmission unit 14 includes a pinion 17 provided on the outer peripheral surface of the transmission shaft 15, and the pinion 17 is exposed from an opening 12 a formed in the input shaft 12. A disc-shaped eccentric cam 18 divided into two in the direction of the axis L is splined to the outer periphery of the input shaft 12 so as to sandwich the pinion 17. The center O1 of the eccentric cam 18 is eccentric with respect to the axis L of the input shaft 12 by a distance d. Further, the six eccentric cams 18 of the six transmission units 14 are offset in phase by 60 ° from each other.

  On the outer peripheral surface of the eccentric cam 18, a pair of eccentric recesses 19 a and 19 a formed on both end surfaces in the axis L direction of the disc-shaped eccentric disk 19 are rotatably supported via a pair of needle bearings 20 and 20. . The center O1 of the eccentric recesses 19a, 19a (that is, the center O1 of the eccentric cam 18) is shifted from the center O2 of the eccentric disk 19 by a distance d. That is, the distance d between the axis L of the input shaft 12 and the center O1 of the eccentric cam 18 and the distance d between the center O1 of the eccentric cam 18 and the center O2 of the eccentric disk 19 are the same.

  A pair of crescent-shaped guide portions 18a and 18a are provided on the split surface of the eccentric cam 18 divided into two in the direction of the axis L so as to be coaxial with the center O1 of the eccentric cam 18. The tooth tips of the ring gear 19b formed so as to communicate between the bottoms of the recesses 19a and 19a slidably contact the outer peripheral surfaces of the guide portions 18a and 18a of the eccentric cam 18. Then, the pinion 17 of the transmission shaft 15 meshes with the ring gear 19b of the eccentric disk 19 through the opening 12a of the input shaft 12.

  One end side of the input shaft 12 is directly supported on one side wall 11 a of the mission case 11 via a ball bearing 21. A cylindrical portion 18b provided integrally with one eccentric cam 18 located on the other end side of the input shaft 12 is supported on the side wall 11b on the other end side of the mission case 11 via a ball bearing 22. The other end side of the input shaft 12 splined to the inner periphery of the eccentric cam 18 is indirectly supported by the mission case 11.

  The speed change actuator 23 that changes the speed ratio of the continuously variable transmission T by rotating the speed change shaft 15 relative to the input shaft 12 is supported by the transmission case 11 so that the motor shaft 24a is coaxial with the axis L. A motor 24 and a planetary gear mechanism 25 connected to the electric motor 24 are provided. The planetary gear mechanism 25 includes a carrier 27 that is rotatably supported by an electric motor 24 via a needle bearing 26, a sun gear 28 that is fixed to the motor shaft 24a, and a plurality of two stations that are rotatably supported by the carrier 27. A pinion 29, a first ring gear 30 splined to the shaft end of the hollow input shaft 12 (strictly speaking, the cylindrical portion 18b of the one eccentric cam 18), and a spline to the shaft end of the transmission shaft 15 And a second ring gear 31 coupled thereto. Each double pinion 29 includes a first pinion 29a having a large diameter and a second pinion 29b having a small diameter. The first pinion 29a meshes with the sun gear 28 and the first ring gear 30, and the second pinion 29b has a second ring gear. Mesh with 31.

  On the outer periphery of the eccentric disk 19, an annular portion 33 a on one end side of the connecting rod 33 is supported via a roller bearing 32 so as to be relatively rotatable.

  The output shaft 13 is supported by a pair of ball bearings 34 and 35 on a pair of side walls 11a and 11b of the mission case 11, and a one-way clutch 36 is provided on the outer periphery thereof. The one-way clutch 36 includes a ring-shaped outer member 38 pivotally supported at the tip of the rod portion 33b of the connecting rod 33 via a pin 37, and an inner member disposed inside the outer member 38 and fixed to the output shaft 13. 39 and a plurality of rollers 41 arranged in a wedge-shaped space formed between the inner circular arc surface of the outer member 38 and the outer peripheral plane of the inner member 39 and biased by a plurality of springs 40. … And.

  As shown in FIGS. 6 and 8, since the center O1 of the eccentric recesses 19a and 19a (that is, the center O1 of the eccentric cam 18) is shifted from the center O2 of the eccentric disk 19 by a distance d, the outer circumference of the eccentric disk 19 And the inner periphery of the eccentric recesses 19a, 19a are non-uniform in the circumferential direction, and crescent-shaped thinning recesses 19c, 19c are formed at portions where the interval is large.

  As shown in FIGS. 9 and 11, the six speed change units 14... Go from the other end side (shift actuator 23 side) to the one end side (engine E and differential gear D side) of the input shaft 12 and the output shaft 13. # 1, # 2, # 3, # 4, # 5, and # 6. An inner member 39 facing the arcuate inner peripheral surface of the outer member 38 of the one-way clutch 36 via rollers 41... Is inclined with a predetermined inclination angle with respect to the tangential direction of the inner peripheral surface. 39a... Are formed between the outer member 38 and the inner member 39 by the inclined surfaces 39a.

  The inclination angle θ1 of the inclined surface 39a of the inner member 39 of the one-way clutch 36 (see FIG. 9A) of the # 1 transmission unit 14 is set large, and the one-way clutch 36 (see FIG. The inclination angle θ6 of the inclined surface 39a of the inner member 39 is set small, and the inclination angle of the inclined surface 39a of the inner member 39 of the one-way clutch 36 of the transmission units 14 to # 5 is # 2 to # 5, It gradually decreases so as to interpolate between θ1 and θ6.

  Next, the operation of one transmission unit 14 of the continuously variable transmission T will be described.

  As is clear from FIGS. 5 and 7A to 7D, when the input shaft 12 is rotated by the engine E when the center O2 of the eccentric disk 19 is eccentric with respect to the axis L of the input shaft 12. As the annular portion 33a of the connecting rod 33 rotates eccentrically around the axis L, the rod portion 33b of the connecting rod 33 reciprocates.

  As a result, in FIG. 9, when the connecting rod 33 is reciprocated and pulled to the left in the figure, the rollers 41 urged by the springs 40 engage the wedge-shaped space between the outer member 38 and the inner member 39. The outer member 38 and the inner member 39 are coupled via the rollers 41... So that the one-way clutch 36 is engaged and the movement of the connecting rod 33 is transmitted to the output shaft 13. On the other hand, when the connecting rod 33 is reciprocated, the rollers 41 are pushed out of the wedge-shaped space between the outer member 38 and the inner member 39 while compressing the springs 40. As the inner members 39 slip each other, the one-way clutch 36 is disengaged and the movement of the connecting rod 33 is not transmitted to the output shaft 13.

  Thus, since the rotation of the input shaft 12 is transmitted to the output shaft 13 for a predetermined time while the input shaft 12 rotates once, the output shaft 13 rotates intermittently when the input shaft 12 rotates continuously. Since the eccentric disks 19 of the six transmission units 14 are out of phase with each other by 60 °, the six transmission units 14 alternately transmit the rotation of the input shaft 12 to the output shaft 13. Thus, the output shaft 13 rotates continuously.

  At this time, as the eccentric amount ε of the eccentric disk 19 increases, the reciprocating stroke of the connecting rod 33 increases, and the one-time rotation angle of the output shaft 13 increases, and the transmission ratio of the continuously variable transmission T decreases. Conversely, the smaller the eccentric amount ε of the eccentric disk 19, the smaller the reciprocating stroke of the connecting rod 33, the smaller the rotation angle of the output shaft 13, and the higher the gear ratio of the continuously variable transmission T. When the eccentric amount ε of the eccentric disk 19 becomes zero, the connecting rod 33 stops moving even when the input shaft 12 rotates, so the output shaft 13 does not rotate, and the gear ratio of the continuously variable transmission T is maximized ( Infinity).

  When the transmission shaft 15 does not rotate relative to the input shaft 12, that is, when the input shaft 12 and the transmission shaft 15 rotate at the same speed, the transmission ratio of the continuously variable transmission T is maintained constant. In order to rotate the input shaft 12 and the transmission shaft 15 at the same speed, the electric motor 24 may be rotationally driven at the same speed as the input shaft 12. The reason is that the first ring gear 30 of the planetary gear mechanism 25 is connected to the input shaft 12 and rotates at the same speed as the input shaft 12. When the electric motor 24 is driven at the same speed, the sun gear 28 and the first ring gear 30 are driven. Rotate at the same speed, the planetary gear mechanism 25 is locked and rotates as a whole. As a result, the input shaft 12 and the transmission shaft 15 connected to the first ring gear 30 and the second ring gear 31 that rotate integrally are integrated and rotate at the same speed without relative rotation.

  When the rotational speed of the electric motor 24 is increased or decreased with respect to the rotational speed of the input shaft 12, the first ring gear 30 coupled to the input shaft 12 and the sun gear 28 connected to the electric motor 24 rotate relative to each other. The carrier 27 rotates relative to the first ring gear 30. At this time, the gear ratio of the first ring gear 30 and the first pinion 29a meshing with each other is slightly different from the gear ratio of the second ring gear 31 and the second pinion 29b meshing with each other. And the transmission shaft 15 connected to the second ring gear 31 rotate relative to each other.

  When the transmission shaft 15 rotates relative to the input shaft 12 in this manner, the eccentric recesses 19 a and 19 a of the eccentric disk 19 in which the ring gear 19 b is engaged with the pinion 17 of each transmission unit 14 are integrated with the input shaft 12. The cam 18 rotates while being guided by the guide portions 18a, 18a, and the eccentric amount ε of the center O2 of the eccentric disk 19 with respect to the axis L of the input shaft 12 changes.

  FIG. 7A shows a state where the speed ratio is minimum (speed ratio: TD). At this time, the eccentric amount ε of the center O2 of the eccentric disk 19 with respect to the axis L of the input shaft 12 is the axis L of the input shaft 12. To a center O1 of the eccentric cam 18 and a maximum value equal to 2d, which is the sum of the distance d from the center O1 of the eccentric cam 18 to the center O2 of the eccentric disk 19. As shown in FIGS. 7B and 7C, when the transmission shaft 15 rotates relative to the input shaft 12, the eccentric disk 19 rotates relative to the eccentric cam 18 integral with the input shaft 12. Furthermore, the eccentric amount ε of the center O2 of the eccentric disk 19 with respect to the axis L of the input shaft 12 is gradually decreased from the maximum value 2d, and the transmission ratio is increased. When the transmission shaft 15 further rotates relative to the input shaft 12, the eccentric disk 19 further rotates relative to the eccentric cam 18 integral with the input shaft 12, and finally, as shown in FIG. The center O2 of the eccentric disk 19 overlaps the axis L of the input shaft 12, the eccentricity ε becomes zero, the transmission gear ratio is maximized (infinite) (transmission ratio: UD), and power is transmitted to the output shaft 13. Blocked.

  Next, the effect | action which smoothes the torque transmitted to the output shaft 13 is demonstrated.

  As already described with reference to FIG. 11, the driving force is input to the output shaft 13 from the one-way clutches 36 of the six transmission units 14 to # 6 juxtaposed in the axial direction. Since the driving force is output to the differential gear D connected to the side (# 6 side), the twist angle of the output shaft 13 due to the torque transmitted from the one-way clutch 36 is connected to the driving wheel. It continuously changes so as to be minimum on one end side (# 6 side) close to the differential gear D that receives a rotational load and maximum on the other end side (# 1 side) far from the differential gear D.

  In order to eliminate the difference in transmission torque that is different for each transmission unit 14... And to make it uniform, the torque transmission amount of the one-way clutch 36 on the # 1 side where torque is difficult to transmit is increased, and the one-way on the # 6 side where torque is easily transmitted What is necessary is just to reduce the torque transmission amount of the clutch 36. According to the present embodiment, the one-way clutch 36 on the # 1 side where torque is hardly transmitted has a large inclination angle θ1 of the inclined surface 39a... Of the inner member 39 (see FIG. 9A). The rollers 41 are quickly engaged between the members 39, and the one-way clutch 36 is quickly engaged to increase the torque transmission amount. On the other hand, the one-way clutch 36 on the # 6 side where torque is easily transmitted has a small inclination angle θ6 of the inclined surface 39a... Of the inner member 39 (see FIG. 9B), and therefore the roller 41 between the outer member 38 and the inner member 39. ... takes time, and the engagement of the one-way clutch 36 is delayed and the torque transmission amount is reduced.

  In this way, by increasing the torque transmission amount of the one-way clutch 36 to which torque is difficult to be transmitted and decreasing the torque transmission amount of the one-way clutch 36 in which torque is easily transmitted, the one-way clutches 36 of # 1 to # 6. The torque transmission amount can be made uniform, and the torque fluctuation ΔT of the output shaft 13 can be reduced as compared with the comparative example, as shown in FIG.

  Further, since the phases of the eccentric disks 19 of the plurality of transmission units 14 are sequentially changed by 60 ° from one end side to the other end side of the input shaft 12, the output shaft 13 is compared with a case where it is changed randomly. The torque fluctuation becomes larger. Therefore, if this embodiment is applied in such a case, the effect of reducing the torque fluctuation of the output shaft 13 can be more effectively exhibited.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, the drive source of the present invention is not limited to the engine E of the embodiment, and may be another drive source such as an electric motor.

  The continuously variable transmission T according to the embodiment includes six transmission units 14... However, the number of the transmission units 14 is not limited to six.

12 Input shaft 13 Output shaft 14 Transmission unit 19 Eccentric disc (input side fulcrum)
33 Connecting rod 36 One-way clutch 37 Pin (output fulcrum)
38 Outer member 39 Inner member 39a Inclined surface 41 Roller E Engine (drive source)
L Input shaft axis ε Eccentricity

Claims (2)

Between the input shaft (12) and the output shaft (13), a plurality of transmission units (14) for shifting the rotation of the input shaft (12) connected to the drive source (E) and transmitting it to the output shaft (13) Juxtaposed in the axial direction,
Each of the transmission units (14)
An input side fulcrum (19) that is variable in eccentricity (ε) from the axis (L) of the input shaft (12) and rotates together with the input shaft (12);
A one-way clutch (36) connected to the output shaft (13);
An output fulcrum (37) provided on an outer member (38) of the one-way clutch (36);
A connecting rod (33) connected at both ends to the input side fulcrum (19) and the output side fulcrum (37) and reciprocating;
In the vehicle power transmission device, the phases of the input side fulcrums (19) of the plurality of transmission units (14) are different from each other, and a driving force is output from one shaft end side of the output shaft (13). There,
The one-way clutch (36) of the plurality of transmission units (14) is fixed to the output shaft (13) and faces an inner peripheral surface of the outer member (38) via a roller (41). 39a) provided with an inner member (39), and the inclination angle of the inclined surface (39a) is gradually increased from one axial end side to the other axial end side of the output shaft (13). A power transmission device for a vehicle characterized by being set.   The phase of the input side fulcrum (19) of the plurality of transmission units (14) is sequentially changed from one shaft end side to the other shaft end side of the input shaft (12), The power transmission device for a vehicle according to claim 1.

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