JP2009078598A - Driving force transmission device of hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a driving force transmission device of a hybrid vehicle that prevents a two-way clutch from being switched into an engagement when traveling by the drive of an engine. <P>SOLUTION: This device comprises front wheels 11, which are rotation driven by the engine 13 as a driving source, and rear wheels 12, which are rotation driven by an electric motor 16 with a speed reducer. The mechanical two-way clutch 19 is built in a torque transmission path from an output shaft 18 of the speed reducer 17 of the electric motor 16 to the rear wheels 12 to prevent the transmission of rotary torque from the rear wheels 12 to the output shaft 18 when the vehicle travels by the drive of the engine 13. A reverse input cutoff clutch 30 is provided in a torque transmission system from the output shaft 18 of the speed reducer 17 to the two-way clutch 19. When a reverse input load is applied to the output shaft 18 by an external force of vibration etc. while traveling with the front wheels 11 driven by the engine 13, the reverse input is shut off by the reverse input cutoff clutch 30 to prevent the two-way clutch 19 from being engaged in the direction of impeding the rotation of the rear wheels. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a driving force transmission device for a hybrid vehicle in which driving wheels are driven by an engine and auxiliary driving wheels are driven by an electric motor with a reduction gear.

  As a driving force transmission device for a hybrid vehicle that includes an engine and an electric motor and that is used as an assist when the load is large when starting or accelerating, the one described in Patent Document 1 has been conventionally used. Are known.

  In the driving force transmission device described in Patent Document 1, a two-way clutch is incorporated in the torque transmission path from the output shaft of the speed reducer that decelerates the rotation of the electric motor to the auxiliary driving wheel, and during normal traveling by driving the engine. The two-way clutch interrupts transmission of rotational torque from the auxiliary drive wheels to the speed reducer.

  Here, as a two-way clutch, two cages with different diameters are incorporated between the outer ring and the inner ring, and a sprag is incorporated into a pocket formed in each of the cages, and a large-diameter outer cage and a small-diameter inner cage. A sprag type two-way clutch is employed in which the sprag is tilted in the circumferential direction by the relative rotation of the inner ring and the cam surfaces at both ends of the sprag are engaged with the inner diameter surface of the outer ring and the outer diameter surface of the inner ring.

JP 11-291774 A

  By the way, in the driving force transmission device for a hybrid vehicle described in Patent Document 1, when the output shaft of the speed reducer rotates due to vibration or the like during forward traveling by driving the engine, the rotation of the motor is stopped. Is transmitted to the outer ring of the two-way clutch, the sprag tilting forward is switched to the reverse side to be engaged, the rotation of the auxiliary drive wheel is transmitted to the speed reducer side, and the rotation of the auxiliary drive wheel is The problem of being disturbed occurs.

  In addition, when the reverse drive is performed by driving the engine with the electric motor stopped, the sprag tilting to the reverse side is switched to the forward side to be in the engaged state as described above, and the rotation of the auxiliary drive wheel is decelerated. There is a problem that the rotation of the auxiliary drive wheel is obstructed by being transmitted to the machine side.

  An object of the present invention is that a two-way clutch incorporated in a torque transmission system that transmits the rotation of an electric motor to an auxiliary drive wheel engages in a direction that inhibits the rotation of the auxiliary drive wheel during traveling by driving the engine. It is an object of the present invention to provide a driving force transmission device for a hybrid vehicle that can be prevented.

  In order to solve the above-described problems, the present invention includes a drive wheel that is rotationally driven using an engine as a drive source, and an auxiliary drive wheel that is rotationally driven using an electric motor with a speed reducer as a drive source. In a driving force transmission device for a hybrid vehicle in which a mechanical two-way clutch is incorporated in a torque transmission path from the output shaft of the speed reducer to the auxiliary drive wheel, a torque transmission system from the output shaft of the speed reducer to the two-way clutch is used. Since the rotation of the output shaft of the electric motor is disengaged and the rotation of the output shaft is transmitted, and the reverse input cutoff clutch that cuts off the torque input from the two-way clutch side to the output shaft is adopted. is there.

  Here, a drive shaft for transmitting the rotation of the output shaft to the two-way clutch is provided on the same axis as the output shaft, and a reverse input cutoff clutch is incorporated between the drive shaft and the output shaft. A torque transmission pin is provided on one of the end surfaces of the drive shaft opposite to this, and an insertion portion into which the torque transmission pin is inserted is formed on the other. Between the insertion portion and the torque transmission pin, the output shaft with respect to the drive shaft is provided. By adopting a configuration in which a clearance in the rotation direction that allows the engagement of the reverse input cutoff clutch to be released by relative rotation is adopted, the operation of releasing the engagement of the reverse input cutoff clutch by the rotation of the output shaft, and after the engagement is released, The operation of transmitting the rotational torque from the output shaft to the drive shaft can be continuously performed.

  In the driving force transmission device for a hybrid vehicle that employs the torque transmission pin as described above, an outer ring that is fixed to a stationary member and covers a shaft end portion of the drive shaft as a reverse input cutoff clutch, and a shaft end of the output shaft A plurality of cages disposed in an annular space between the outer ring and the drive shaft, and forming a wedge space between the outer circumference of the shaft end of the drive shaft and the cylindrical inner surface of the outer ring. Cam surfaces are provided at equal intervals in the circumferential direction, and a pocket is formed in the cage at a position facing each cam surface, and a normal rotation roller and a reverse rotation roller are incorporated in each pocket, and an elastic member is provided between the rollers. The reverse input blocking clutch is applied to the driving force transmission device by adopting a built-in configuration in which the forward rotation roller and the reverse rotation roller are urged toward the narrow portion of the wedge space. Easy assembly It is, the driving force transmission device can be prevented from increasing in size.

Here, the retainer is rotated by the electric motor, and the disengagement torque when the forward rotation roller or the reverse rotation roller is disengaged by the rotation of the retainer is defined as T _1. is rotational moment load on the output shaft, when the load torque applied to the forward rotation roller or reversing roller from retainer shaft end of the output shaft and the T _2, relationship of T _1> T ₂ is satisfied By setting the engagement release torque in this manner, the rotation of the output shaft can be reliably transmitted to the drive shaft when the electric motor is driven. In addition, when the electric motor is stopped, the retainer can be reliably prevented from rotating by the contact of the end face of the pocket with the forward rotation roller or the reverse rotation roller, and the output shaft can be reliably rotated by external force such as vibration. Can be prevented.

  In the driving force transmission device for a hybrid vehicle according to the present invention, the two-way clutch may be a sprag type clutch or a roller type clutch.

  As described above, in the present invention, the torque transmission system extending from the output shaft of the speed reducer to the two-way clutch is disengaged by the rotation of the output shaft by the drive of the electric motor to permit the rotation of the output shaft, and By providing a reverse input cut-off clutch that cuts off torque input from the two-way clutch side to the output shaft, external forces such as vibration and the like from the two-way clutch side when driving the vehicle from the electric motor to the engine are switched. It is possible to prevent the output shaft from rotating due to the torque input. For this reason, the outer ring of the two-way clutch does not rotate when the vehicle is driven by driving the engine, and it is possible to reliably prevent the two-way clutch from being engaged in a direction that inhibits the rotation of the auxiliary drive wheel. .

  Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the hybrid vehicle 10 is provided with front wheels 11 as drive wheels on the left and right at the front of the vehicle body. A rear wheel 12 as an auxiliary drive wheel is provided at the rear of the vehicle body.

  Further, an engine 13 and an electric motor 16 with a reduction gear are mounted on the vehicle body, and the rotation of the engine 13 is transmitted to the front wheels 11 via the transmission 14 and the differential 15. On the other hand, the rotation of the output shaft 18 of the speed reducer 17 in the electric motor 16 is transmitted to the rear wheel 12 via the two-way clutch 19 and the differential 20.

  2 and 3 show a torque transmission system of the electric motor 16. A drive shaft 21 is provided coaxially with the output shaft 18 of the speed reducer 17. A drive shaft is provided between the drive shaft 21 and the output shaft 18. A reverse input cutoff clutch 30 that shuts off torque input from the output shaft 18 to the output shaft 18 and a torque transmission means 40 that transmits the rotation of the output shaft 18 driven by the electric motor 16 to the drive shaft 21 are provided.

  As shown in FIGS. 3 and 4, the reverse input cutoff clutch 30 is provided at an outer ring 31 that is fixed to a housing 22 as a stationary member and covers a shaft end portion of the drive shaft 21, and a shaft end of the output shaft 18. And a cage 32 disposed in an annular space between the outer ring 31 and the drive shaft 21, and a wedge space is formed between the outer periphery of the shaft end of the drive shaft 21 and the cylindrical inner surface 33 of the outer ring 31. A plurality of cam surfaces 34 are provided at equal intervals in the circumferential direction, and a pocket 35 is formed in the cage 32 at a position facing each cam surface 34, and a normal rotation roller 36 a and a reverse rotation roller 36 b are provided in each pocket 35. The elastic member 37 is assembled between the rollers 36a and 36b, and the rollers 36a and 36b are urged toward the direction in which the rollers 36a and 36b are engaged with the narrow portion of the wedge space.

Here, the output shaft 18 is rotated by driving the electric motor 16, the end surface of the pocket 35 of the cage 32 presses the forward rotation roller 36 a or the reverse rotation roller 36 b, and the rollers 36 a, 36 b become the cylindrical inner surface 33 and the disengagement torque required to release engagement with respect to the cam surface 34 and T _1, the drive shaft 21 or the output shaft 18 is rotated by an external force such as vibration, pressing the end face of the pocket 35 rollers 36a, 36b, when a load torque when the pressure is loaded to the T _2, T _1> as equation T ₂ is satisfied, the disengagement torque T ₁ of the roller is set.

  Here, the cam surface 34 is formed of two inclined surfaces 34a and 34b inclined in opposite directions, but a single flat surface may be used as the cam surface 34. In addition, the elastic member 37 is divided into two parts, and the divided elastic member is received by a projecting piece-like spring seat 38 provided in the intersection of the two inclined surfaces 34a and 34b and disposed in the pocket 35. A single elastic member 37 may bias both rollers 36a and 36b in opposite directions.

  The torque transmission means 40 is provided with a torque transmission pin 41 at an end surface eccentric position of the output shaft 18, and the torque transmission pin 41 is inserted into a groove 42 formed on the end surface of the drive shaft 21 as an insertion portion extending in the radial direction. Thus, the torque transmission pin 41 pushes both side surfaces of the groove 42.

  Here, a rotational clearance 43 is formed between the side surfaces of the torque transmission pin 41 and the groove 42, and the rotational clearance 43 is a pocket 35 formed in the cage 32 by the relative rotation of the output shaft 18 and the drive shaft 21. These end surfaces are sized such that the forward rotation roller 36a or the reverse rotation roller 36b can be pressed to release the engagement.

  A groove may be formed on the end surface of the output shaft 18 and a torque transmission pin may be provided at the end surface eccentric position of the drive shaft 21. Further, instead of the groove 42, an arc-shaped long hole may be provided.

  As shown in FIG. 3, a drive gear 23 that transmits the rotation of the drive shaft 21 to the two-way clutch 19 is fixed to the drive shaft 21. The two-way clutch 19 holds an outer ring 50, an inner ring 51 incorporated inside the outer ring 50, a sprag 52 incorporated between the cylindrical inner surface 50 a of the outer ring 50 and the cylindrical outer surface 51 a of the inner ring 51, and the sprag 52. And a cage 53.

  The outer ring 50 and the inner ring 51 are relatively rotatably supported via a bearing 54, and an input gear 55 provided on the outer ring 50 is engaged with the drive gear 23.

  As shown in FIG. 5, the retainer 53 includes two retainers 53 a and 53 b having different diameters, and the outer retainer 53 a is fixed to the cylindrical inner surface 50 a of the outer ring 50 so as to rotate integrally with the outer ring 50. It has become.

  On the other hand, the inner cage 53b is rotatably supported on the inner ring 51 by a bearing 56 shown in FIG. A switch pin 57 extending radially outward is fixed to the inner cage 53b, and the switch pin 57 is inserted into a long hole 58 formed in the outer cage 53a in the circumferential direction. The outer cage 53a and the inner cage 53b are relatively rotatable within a range in contact with both ends of the long hole 58 in the circumferential direction.

  A plurality of pockets 59 that are opposed to each other in the radial direction are formed in the outer cage 53a and the inner cage 53b at intervals in the circumferential direction, and a sprag 52 is incorporated in each of the pockets 59 that are opposed in the radial direction.

  The sprag 52 has a forward rotation cam surface 52a and a reverse rotation cam surface 52b at both ends, and the cylindrical inner surface 50a of the outer ring 50 and the inner ring 51 of the inner ring 51 are elastically assembled into the pocket 59 of the inner cage 53b. It is held in a neutral position where it is disengaged from the cylindrical outer surface 51a.

  As shown in FIG. 3, one end of the inner cage 53b is located outside the end of the outer cage 53a, and a flange 61 and a gear fitting surface 62 are formed on the outer periphery of one end of the inner cage 53b. An engagement groove 63 is provided in the gear fitting surface 62.

  A sub gear 64 is rotatably fitted to the gear fitting surface 62, and the sub gear 64 is pressed against the flange 61 by an elastic member 65 such as a disc spring incorporated in the engaging groove 63.

  The sub gear 64 meshes with the drive gear 23, and the number of teeth on the outer periphery is larger than the number of teeth on the input gear 55. For this reason, when the drive gear 23 rotates, the sub gear 64 rotates behind the input gear 55 while slipping at the contact portion with the flange 61.

  A differential case 66 of the differential 20 is fixed to the inner ring 51, and when rotational torque is transmitted from the inner ring 51 to the differential case 66, the rotational torque is shown in FIG. 1 via the differential mechanism 67 shown in FIG. It is transmitted to the axle 68 of the rear wheel 12.

  The driving force transmission device for a hybrid vehicle shown in the embodiment has the above-described structure, and drives the electric motor 16 when starting. The rotation of the electric motor 16 is decelerated by the speed reducer 17 and output from the output shaft 18. The output shaft 18 has a rotational direction clearance 43 formed between the torque transmission pin 41 and the groove 42 with respect to the drive shaft 21. Relative rotation in range.

  By relative rotation of the output shaft 18 and the drive shaft 21, the end surface of the pocket 35 formed in the retainer 32 presses the forward rotation roller 36a or the reverse rotation roller 36b in the circumferential direction.

  Here, when the cage 32 that rotates integrally with the output shaft 18 rotates in the direction indicated by the arrow in FIG. 4, the reverse rotation roller 36 b is pushed by the end face of the pocket 35 and engaged with the cylindrical inner surface 33 and the cam surface 34. After the engagement is released, the torque transmission pin 40 is engaged with the side surface of the groove 42, and the rotation of the output shaft 18 is transmitted to the drive shaft 21 via the torque transmission pin 40.

  At this time, since the reverse rotation roller 36b is in a disengaged state, the drive shaft 21 rotates in the same direction as the output shaft 18 without being inhibited from rotating, and the rotation of the output shaft 18 causes the drive gear 23 to rotate. To the input gear 55 and the sub-gear 64. For this reason, the outer ring 50 rotates, and the inner cage 53 b also rotates in the same direction as the outer ring 50 due to the contact between the sub gear 64 and the flange 61.

  At this time, since the number of teeth of the sub gear 64 is larger than the number of teeth of the input gear 55, the sub gear 64 rotates behind the input gear 55 while slipping at the contact portion with the flange 61, and is held outside fixed to the outer ring 50. The container 53a and the inner holder 53b rotate relative to each other.

  Due to the relative rotation of the outer cage 53a and the inner cage 53b, the sprag 52 falls in the rotational direction of the outer cage 53a and engages with the cylindrical inner surface 50a of the outer ring 50 and the cylindrical outer surface 51a of the inner ring 51.

  When the outer cage 53a and the inner cage 53b rotate relative to each other by a predetermined angle, one end of the long hole 58 formed in the outer cage 53a contacts the switch pin 57, and the rotation of the outer cage 53a The inner retainer 53b is transmitted to the retainer 53b and rotates integrally with the outer retainer 53a, and the sprag 52 is retained in the engaged state. Further, the sub gear 64 rotates while sliding at the contact portion with the flange 61.

  By the engagement of the sprag 52 in the two-way clutch 19, the rotation of the outer ring 50 is transmitted to the inner ring 51 through the sprag 52. Further, the rotation of the inner ring 51 is transmitted from the differential case 66 fixed to the inner ring 51 to the axle 68 shown in FIG. 1 through the differential mechanism 67, and the rear wheel 12 is rotated to drive the vehicle.

  When switching the running of the vehicle from the electric motor 16 to the engine 13, the start clutch (not shown) is put into a coupled state, the rotation of the engine 13 is input to the transmission 14, and the front wheels 11 are rotated.

  In the traveling state of the vehicle driven by the engine 13, the rotation of the rear wheel 12 is transmitted to the inner wheel 51 of the two-way clutch 19, and the inner wheel 51 rotates. The rotation of the inner ring 51 is not transmitted to the outer ring 50, and the inner ring 51 rotates freely.

  When the vehicle is driven by driving the engine 13, the electric motor 16 is stopped simultaneously with switching of the driving force from the electric motor 16 to the engine 13. When the electric motor 16 is stopped, the reverse rotation roller 36b of the reverse input cut-off clutch 30 is pressed by the elastic member 37 to a standby position where the cylindrical inner surface 33 of the outer ring 31 and the cam surface 34 come into contact as shown in FIG. Returned.

  Here, in the traveling state of the vehicle driven by the engine 13, when an external force such as vibration is applied to the output shaft 18 and a rotational moment is applied to the output shaft 18, the pocket 35 formed in the cage 32 The end face comes into contact with the forward rotation roller 36a or the reverse rotation roller 36b.

At this time, the load torque _{T 2} of the when the pressure force is applied to the rollers 36a, 36b from the end face of the pocket 35, the roller 36a, 36b is required to be disengaged with respect to the cylindrical inner surface 33 and cam surface 34 smaller than the disengagement torque T _1, the output shaft 18 by abutment of the end face of the pocket 35 relative to the forward rotation roller 36a or the reverse rotation roller 36b is held in a stopped state.

  When a rotational moment is applied to the drive shaft 21 by an external force such as vibration, the forward rotation roller 36a or the reverse rotation roller 36b is engaged with the cylindrical inner surface 33 and the cam surface 34 of the outer ring 31, and is driven by the engagement. The shaft 21 is held in a stopped state.

  As described above, the output shaft 18 and the drive shaft 21 do not rotate even when an external force such as vibration is applied to the output shaft 18 and the drive shaft 21 in the traveling state by driving the engine 13. There is no inconvenience that the two-way clutch 19 is engaged in a direction that inhibits the vehicle, and the vehicle can be driven safely.

  In the embodiment shown in FIG. 3, the outer cage 53a and the inner cage 53b are rotated relative to each other using the sub gear 64. However, as shown in FIG. A movable friction plate 70 is rotatably fitted to 62, and the movable friction plate 70 is pressed against the flange 61 by an elastic member 71, and is also brought into elastic contact with a fixed friction plate 72 fixed to the housing 22, so that an inner cage is provided. You may make it load the rotational resistance by friction to 53b.

  Also in the case shown in FIG. 6, the sprag 52 can be switched to the engaged position by relatively rotating the outer retainer 53a and the inner retainer 53b when the rotational torque is transmitted from the drive gear 23 to the input gear 55.

Moreover, in FIG. 3, although the sprag type thing was shown as the two-way clutch 19,
As shown in FIGS. 7 (I) and (II), the gap between the inner diameter surface of the outer ring 80 fixed to the inner diameter surface of the input gear 55 and the cylindrical outer surface 82 of the inner ring 81 toward both ends in the circumferential direction. Is provided with a cam surface 83 that forms a wedge-shaped space that gradually becomes smaller, a roller 84 is incorporated in the wedge-shaped space, the roller 84 is held by a cage 85, and the roller 84 is held by an elastic member 86. The roller type two-way clutch 19 may be used.

  In the roller type two-way clutch 19, a switch pin 87 facing radially outward is fixed to the cage 85, and the switch pin 87 is inserted into a long hole 88 formed in the outer ring 80. The outer ring 80 and the cage 85 are relatively rotatable within a range in which the switch pin 87 abuts on both ends thereof.

  In the use of the roller type two-way clutch 19 as described above, the sub gear 64 is rotatably fitted to the end of the cage 85, and the sub gear 64 is a flange provided on the cage 85 by the elastic member 65. When the rotational torque is transmitted from the drive gear 23 to the input gear 55, the outer ring 80 and the retainer 85 are relatively rotated to engage the roller 84 with the cam surface 83 and the cylindrical outer surface 82. .

  Instead of the sub gear 64, a movable friction plate 70 and a fixed friction plate 72 shown in FIG.

Overall configuration diagram showing an embodiment of a driving force transmission device for a hybrid vehicle according to the present invention 1 is a partially cutaway sectional view of a torque transmission device that transmits the rotation of the electric motor shown in FIG. Sectional drawing which expands and shows a part of FIG. Sectional view along line IV-IV in FIG. Sectional drawing which shows a part of two-way clutch Sectional drawing which shows the other example of the switch mechanism of a two-way clutch (I) is a vertical front view showing another example of a two-way clutch, and (II) is a vertical side view.

Explanation of symbols

11 Front wheels (drive wheels)
12 Rear wheels (auxiliary drive wheels)
13 Engine 16 Electric motor with reduction gear 17 Reduction gear 18 Output shaft 19 Two-way clutch 21 Drive shaft 22 Housing (stationary member)
30 Reverse input blocking clutch 31 Outer ring 32 Cage 33 Cylindrical inner surface 34 Cam surface 35 Pocket 36a Forward rotation roller 36b Reverse rotation roller 37 Elastic member 41 Torque transmission pin 42 Groove (insertion portion)
43 Clearance in rotation direction

Claims (6)

Torque transmission from the output shaft of the speed reducer to the auxiliary drive wheel in the electric motor, comprising drive wheels that are driven to rotate using the engine as a drive source and auxiliary drive wheels that are driven to rotate using an electric motor with a speed reducer In a driving force transmission device for a hybrid vehicle incorporating a mechanical two-way clutch in the path,
Disengagement of the output shaft of the electric motor to the torque transmission system from the output shaft of the reduction gear to the two-way clutch to transmit the rotation of the output shaft, and torque from the two-way clutch side to the output shaft A driving force transmission device for a hybrid vehicle, comprising a reverse input blocking clutch for blocking input.   A drive shaft that transmits the rotation of the output shaft to the two-way clutch is provided coaxially with the output shaft, and a reverse input cutoff clutch is built in between the drive shaft and the output shaft. A torque transmission pin is provided on one of the opposite end surfaces of the drive shaft, and an insertion portion into which the torque transmission pin is inserted is formed on the other. Between the insertion portion and the torque transmission pin, the output shaft rotates relative to the drive shaft. The driving force transmission device for a hybrid vehicle according to claim 1, further comprising a clearance in a rotational direction that enables disengagement of the reverse input cutoff clutch.   The reverse input cutoff clutch is fixed to a stationary member and covers an outer ring that covers the shaft end of the drive shaft, and a holding provided at the shaft end of the output shaft and disposed in an annular space between the outer ring and the drive shaft A plurality of cam surfaces forming a wedge space between the outer peripheral surface of the shaft end portion of the drive shaft and the cylindrical inner surface of the outer ring at equal intervals in the circumferential direction. Pockets are formed at positions facing each other, a normal rotation roller and a reverse rotation roller are incorporated in each pocket, and an elastic member is incorporated between the two rollers, so that the normal rotation roller and the reverse rotation roller are placed in a narrow portion of the wedge space. The driving force transmission device for a hybrid vehicle according to claim 2, wherein the driving force transmission device is configured to be biased toward a biting direction. Rotating the cage by an electric motor, and the disengagement torque when the forward rotation roller or the reverse rotation roller by the rotation of the retainer disengages the T _1, in the stop state of the electric motor, the output shaft by an external force It is rotational moment load, engaging the load torque applied to the forward rotation roller or reversing roller from retainer shaft end of the output shaft when the T _2, as relation T _1> T ₂ is satisfied The driving force transmission device for a hybrid vehicle according to claim 3, wherein a mating release torque is set.   The driving force transmission device for a hybrid vehicle according to any one of claims 1 to 4, wherein the two-way clutch is a sprag type clutch.   The driving force transmission device for a hybrid vehicle according to any one of claims 1 to 4, wherein the two-way clutch is a roller type clutch.

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