JP2009078751A - 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 to an engagement state when traveling by the drive of an engine. <P>SOLUTION: Between a holder 25 of the two-way clutch 19 and a housing 33, a frictional resistance giving means 40 is built in that gives frictional resistance to the holder 25 so as to engage a sprag 24 by making an outer ring 22 of the two-way clutch 19 and the holder 25 rotate relatively when driven by an electric motor. Also, an elastic member 51, which gives rotational resistance to the outer ring 22, is built in between a friction plate 44, which forms a frictional resistance giving means 40, and the outer ring 22. The outer ring 22 of the two-way clutch 19 is made to rotate by vibration etc. when the vehicle travels by the drive of the engine to prevent the two-way clutch 19 from being engaged in the direction that impedes the rotation of 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 sprags are incorporated into the pockets formed in the respective cages, and the relative relationship between the large-diameter side cage and the small-diameter side cage A sprag type two-way clutch is employed in which the sprag is tilted in the circumferential direction by rotation so that 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 is rotated by an external force such as vibration during the forward traveling by driving the engine, the electric motor is stopped. The rotation is transmitted to the outer ring of the two-way clutch, the sprag tilting forward is switched to the reverse side to be engaged, and the rotation of the auxiliary drive wheel is transmitted to the speed reducer side. The trouble that rotation is inhibited 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 to provide a driving force transmission device for a hybrid vehicle that can prevent the two-way clutch from engaging in a direction that inhibits the rotation of auxiliary driving wheels during traveling by driving the engine. It is.

  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. A two-way clutch is incorporated in the torque transmission path from the output shaft of the speed reducer to the auxiliary drive wheel, and the two-way clutch is connected between the outer ring to which the rotational torque from the speed reducer is input and the inner ring incorporated in the inner ring. A mechanical type two-way clutch that incorporates an engagement element and a retainer that holds the engagement element, and engages the engagement element with the opposing surfaces of the outer ring and the inner ring by relative rotation of the retainer with respect to the outer ring, In the driving force transmission device for a hybrid vehicle, the two-way clutch cage is provided with friction resistance applying means for applying friction resistance due to slipping. During the switch of the outer ring and the stationary system member relative to the outer ring, than is adopted the configuration in which the rotation resistance applying means for applying rotational resistance to the outer ring.

  In the driving force transmission device for a hybrid vehicle configured as described above, when the electric motor is driven and the rotation is transmitted to the outer ring of the two-way clutch, the outer ring and the cage to which frictional resistance is imparted by the frictional resistance imparting means are relative to each other. Rotate. Due to the relative rotation, the engaging element engages the opposing surfaces of the outer ring and the inner ring, the rotation of the outer ring is transmitted to the inner ring through the engaging element, the rotation of the inner ring is transmitted to the auxiliary driving wheel, and the auxiliary driving wheel rotates. .

  When the drive is switched from the electric motor to the engine to rotate the drive wheel and the electric motor is stopped after switching the drive, the rotation from the auxiliary drive wheel is transmitted to the inner ring and the inner ring rotates. Since the rotation is in a direction to return the coupling to the neutral position, the engagement element is not engaged, the inner ring rotates freely, and rotational torque is not transmitted from the inner ring to the outer ring.

  At this time, since the outer ring is held in a stopped state by the rotation resistance applied from the rotation resistance applying means to the outer ring, the outer ring is not rotated by an external force such as vibration, and the two-way clutch rotates the auxiliary driving wheel. There is no such thing as engaging in the direction that hinders.

  Here, as the rotation resistance applying means, it is possible to adopt a configuration in which an elastic member is incorporated between the opposing surfaces of the outer ring and the stationary system member, and the elastic member is elastically contacted with the opposing surface of the outer ring and the stationary system member. it can.

  In the driving force transmission device for a hybrid vehicle according to the present invention, a friction plate is fitted to the outer periphery of the end portion of the cage as the friction resistance applying means, and the elastic force of the elastic member is applied to one side surface of the friction plate. It is possible to employ a construction in which the opposite side surface is brought into contact with a flange formed on the outer periphery of the cage, and the friction plate is prevented from rotating in a housing that covers the entire two-way clutch.

  In the employment of the frictional resistance applying means, the friction plate can be a stationary member. At this time, if the rotational resistance applied to the outer ring from the friction plate, which is a stationary member, via the rotational resistance applying means is greater than the rotational resistance applied to the cage from the frictional resistance applying means, the electric motor is driven. Since it becomes impossible to rotate the cage relative to the outer ring sometimes, the rotational resistance applied to the outer ring from the rotational resistance applying means is set to a value smaller than the rotational resistance applied to the cage from the friction resistance applying means. deep.

  The stationary member may be a housing that covers the entire two-way clutch. By making the housing a stationary system member, the rotational resistance applied to the outer ring from the rotational resistance applying means can be set to an arbitrary value.

  In the driving force transmission device for a hybrid vehicle according to the present invention, the two-way clutch incorporates two cages having different diameters between the cylindrical inner surface of the outer ring and the cylindrical outer surface of the inner ring, and the outer cage having the larger diameter is connected to the outer ring. This is fixed to the inner surface of the cylinder, and the outer cage and the small-diameter inner cage are provided with pockets facing in the radial direction. The sprags are held in the pockets, and the sprags are held at the approximate center position in the circumferential direction of the pockets. It may be of a sprag type in which a member is incorporated and the sprag is tilted by the relative rotation of the inner cage with respect to the outer cage to engage the cylindrical inner surface of the outer ring and the cylindrical outer surface of the inner ring, Alternatively, an inner ring is incorporated inside the outer ring, and a cam surface is formed on the inner circumference of the outer ring so as to form a wedge-shaped space whose both ends in the circumferential direction are narrow between the inner ring and the cam surface and the cylinder. Holding the rollers incorporated between the outer surface in the retainer, the roller by the relative rotation of the cage relative to the outer ring may be of a roller type which is adapted to engage the cam surface and the cylindrical outer surface.

  As described above, in the present invention, the rotation resistance applying means is provided between the outer ring and the stationary system member to apply the rotation resistance to the outer ring, so that the outer ring is driven by an external force such as vibration when the vehicle is driven by the engine. Is not rotated, and the two-way clutch can be prevented from being engaged in a direction that inhibits the rotation of the auxiliary drive wheels.

  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 gear 21 is attached to the output shaft 18 of the speed reducer 17, and the rotation of the drive gear 21 is input to the two-way clutch 19.

  As shown in FIGS. 3 and 4, the two-way clutch 19 is assembled between an outer ring 22, an inner ring 23 incorporated inside the outer ring 22, and a cylindrical inner surface 22 a of the outer ring 22 and a cylindrical outer surface 23 a of the inner ring 23. The sprag 24 and a holder 25 that holds the sprag 24.

  The outer ring 22 and the inner ring 23 are rotatably supported via a bearing 26, and an input gear 27 provided on the outer ring 22 meshes with the drive gear 21.

  The retainer 25 includes two retainers 25 a and 25 b having different diameters, and the outer retainer 25 a is fixed to the cylindrical inner surface 22 a of the outer ring 22 and rotates integrally with the outer ring 22.

  On the other hand, the inner cage 25 b is rotatably supported on the inner ring 23 by a bearing 28. A switch pin 29 extending radially outward is fixed to the inner holder 25b. The switch pin 29 is inserted into a long hole 30 formed in the outer holder 25a in the circumferential direction, and the switch pin 29 is inserted into the inner holder 25b. The outer retainer 25a and the inner retainer 25b are relatively rotatable within a range in contact with both ends of the long hole 30 in the circumferential direction.

  A plurality of radially opposing pockets 31 are formed in the outer retainer 25a and the inner retainer 25b at intervals in the circumferential direction, and a sprag 24 is incorporated in each of the radially opposing pockets 31.

  The sprag 24 has a forward rotation cam surface 24a and a reverse rotation cam surface 24b at both ends. The sprag 24 is held at a substantially central position in the circumferential direction of the pocket 31 by an elastic member 32 incorporated in the pocket 31 of the inner holder 25b.

  One end of the inner cage 25b is located outside the end of the outer cage 25a. The inner cage 25 b is given a frictional resistance by a frictional resistance applying means 40 provided between the inner holder 25 b and the housing 33.

  The frictional resistance imparting means 40 forms a flange 41 on the outer periphery of the end of the inner cage 25b, and provides an engagement groove 43 on a cylindrical surface 42 formed on the side of the cage end surface from the flange 41. A friction plate 44 as a stationary member is fitted, one side surface of the friction plate 44 is pressed by an elastic member 45 such as a wave spring fitted in the engagement groove 43, and the opposite side surface is pressed against the flange 41. The protrusion 44 a formed on the outer peripheral portion of the friction plate 44 is engaged with a fixed plate 46 fixed to the housing 33 to prevent the friction plate 44 from rotating with respect to the housing 33.

  Between the opposing surfaces of the friction plate 44 and the outer ring 22, rotational resistance applying means 50 that applies rotational resistance to the outer ring 22 is provided. The rotation resistance applying means 50 includes an elastic member 51 such as a wave spring. The elastic member 51 is fitted in an annular groove 52 formed on the surface of the outer ring 22 facing the friction plate 44, and elastically contacts the annular groove 52 and the facing surface of the friction plate 44, respectively. Is given rotational resistance.

  Here, when the rotational resistance applied from the elastic member 51 to the outer ring 22 becomes larger than the frictional resistance acting on the contact portion of the flange 41 in the friction plate 44 and the inner cage 25b, the outer ring 22 is rotated by the drive of the electric motor 16. Since the outer ring 22 and the inner cage 25b rotate together and the sprag 24 cannot be switched to the engaged state, the rotational resistance applied from the elastic member 51 to the outer ring 22 is the friction plate 44 and the flange 41. It is set to a value smaller than the frictional resistance acting on the contact portion.

  As shown in FIGS. 2 and 3, the differential case 60 of the differential 20 is fixed to the inner ring 23, and when rotational torque is transmitted from the inner ring 23 to the differential case 60, the rotational torque is transmitted to the differential mechanism 61. 1 is transmitted to the axle 62 of the rear wheel 12 shown in FIG.

The driving force transmission device for a hybrid vehicle shown in the embodiment has the above structure,
Now, when the electric motor 16 is driven, the rotation of the electric motor 16 is decelerated by the reduction gear 17 and transmitted to the drive gear 21, and the rotation of the drive gear 21 is transmitted to the input gear 27, and the outer ring 22 and its outer ring. The outer cage 25a fixed to 22 rotates in one direction.

  At this time, sliding frictional resistance is applied to the inner cage 25b by the frictional resistance applying means 40, and the frictional resistance is applied to the friction plate 44 from the rotational resistance applying means 50 incorporated between the opposing surfaces of the outer ring 22 and the friction plate 44. Since it is larger than the rotational resistance to be loaded, the inner cage 25b rotates with a delay relative to the outer cage 25a.

  Due to the relative rotation of the outer cage 25a and the inner cage 25b, the sprag 24 falls in the rotational direction of the outer cage 25a, and as shown in FIG. 4 (II), the cylindrical inner surface 22a of the outer ring 22 and the cylinder of the inner ring 23 Engages with the outer shape surface 23a.

  When the outer retainer 25a and the inner retainer 25b rotate relative to each other by a predetermined angle, one end of the long hole 30 formed in the outer retainer 25a comes into contact with the switch pin 29, and the rotation of the outer retainer 25a is inward from the switch pin 29. The inner retainer 25b is transmitted to the retainer 25b and rotates integrally with the outer retainer 25a, and the sprag 24 is retained in the engaged state. Further, the friction plate 44 rotates while sliding at the contact portion with the flange 41.

  By the engagement of the sprag 24 in the two-way clutch 19, the rotation of the outer ring 22 is transmitted to the inner ring 23 through the sprag 24. Further, the rotation of the inner ring 23 is transmitted from the differential case 60 fixed to the inner ring 23 to the axle 62 shown in FIG. 1 through the differential mechanism 61 so that the rear wheel 12 rotates and the vehicle travels.

  When switching the running of the vehicle from the electric motor 16 to the engine 13, after the start clutch (not shown) is engaged, the rotation of the engine 13 is input to the transmission 14, the front wheels 11 are rotated, and the driving force is changed. The electric motor 16 is stopped.

  By stopping the electric motor 16, the sprag 24 is maintained in a standby state in contact with the cylindrical inner surface 22a of the outer ring 22 and the cylindrical outer surface 23a of the inner ring 23, as shown in FIG. 4 (II). Further, in the vehicle running state driven by the engine 13, the rotation of the rear wheel 12 is transmitted to the inner wheel 23 of the two-way clutch 19 and the inner wheel 23 rotates. At this time, since the inner ring 23 rotates faster than the outer ring 22 and rotates in the idling direction with respect to the sprag 24, the rotation of the inner ring 23 is not transmitted to the outer ring 22, and the inner ring 23 rotates freely.

  Here, in the running state of the vehicle driven by the engine 13, the outer ring 22 is loaded with a rotational resistance by an elastic member 51 incorporated between the outer ring 22 and the friction plate 44 and is held in a stopped state. For this reason, even if an external force such as vibration is applied to the output shaft 18 and the outer ring 22, the outer ring 22 does not rotate.

  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 friction plate 44 is a stationary member, and an elastic member 51 is incorporated between the opposing portions of the friction plate 44 and the outer ring 22 to impart rotational resistance to the outer ring 22. As shown in FIG. 5, an elastic member 51 may be incorporated between one side surface of the outer ring 22 and the inner surface of the housing 33 facing the outer ring 22 to impart rotational resistance to the outer ring 22. In this case, the rotational resistance by the elastic member 51 can be set to an arbitrary magnitude regardless of the magnitude of the frictional resistance of the frictional resistance applying means 40.

  In the embodiment shown in FIG. 3, the two-way clutch 19 is shown as a sprag type, but as shown in FIGS. 6 (I) and (II), the outer ring fixed to the inner diameter surface of the input gear 27. A cam surface 74 is provided on the inner diameter surface of the inner ring 72 to form a wedge-shaped space between the cylindrical outer surface 73 of the inner ring 72 and the opposing space gradually decreases toward both ends in the circumferential direction. A roller 75 is placed in the wedge-shaped space. The roller type two-way clutch 19 is incorporated, and the roller 75 is held by a cage 76, and the roller 75 is held at a substantially central position in the circumferential direction of a pocket 76a formed in the cage 76 by an elastic member 77. May be used.

  In the roller type two-way clutch 19, a switch pin 78 facing radially outward is fixed to the retainer 76, and the switch pin 78 is inserted into a long hole 79 formed in the outer ring 71. The outer ring 71 and the retainer 76 are relatively rotatable within a range in which the switch pin 78 is in contact with both ends thereof.

  In the adoption of the roller type two-way clutch 19 as described above, the friction plate 44 is fitted to the outer periphery of the end portion of the retainer 76, and one side surface of the friction plate 44 is pressed by the elastic member 45, The side surface in the opposite direction is pressed against the flange 80 formed on the outer periphery of the end portion of the cage 76, and the friction plate 44 is prevented from rotating around the fixed plate 46 fixed to the housing 33, thereby imparting friction resistance to the outer ring 71.

Overall configuration diagram showing an embodiment of a driving force transmission device for a hybrid vehicle according to the present invention Sectional drawing which shows the torque transmission system of the electric motor of FIG. Sectional drawing which expands and shows a part of FIG. (I) is a cross-sectional view taken along line IV-IV in FIG. 3, and (II) is a cross-sectional view showing an engaged state of a sprag. Sectional drawing which shows the other example of a rotation resistance provision means (I) is a longitudinal front view showing another example of a two-way clutch, and (II) is a sectional view taken along line VI-VI in (I).

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 22 Outer ring 22a Cylindrical inner surface 23 Inner ring 23a Cylindrical outer surface 24 Sprag (engagement element)
25 Cage 25a Outer Cage 25b Inner Cage 31 Pocket 32 Elastic Member 33 Housing (Static System Member)
40 Friction resistance applying means 44 Friction plate (static member)
46 fixed plate 50 rotation resistance applying means 51 elastic member 71 outer ring 72 inner ring 73 cylindrical outer surface 74 cam surface 75 roller (engagement element)
76 Cage 77 Elastic member 80 Flange

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 A two-way clutch is incorporated in the path, and the two-way clutch holds an engagement element between an outer ring to which rotational torque from the speed reducer is input and an inner ring incorporated therein, and a retainer for holding the engagement element. And a mechanical type two-way clutch in which the engagement element is engaged with the opposing surfaces of the outer ring and the inner ring by relative rotation of the cage with respect to the outer ring, and the friction resistance due to slippage is provided to the cage of the two-way clutch. In a driving force transmission device for a hybrid vehicle provided with a frictional resistance applying means for applying,
A driving force transmission device for a hybrid vehicle, characterized in that a rotation resistance applying means for applying a rotation resistance to the outer ring is provided between the outer ring of the two-way clutch and a stationary member for the outer ring.   2. The hybrid vehicle according to claim 1, wherein the rotation resistance applying unit is configured to incorporate an elastic member between opposing surfaces of the outer ring and the stationary system member and elastically contact the elastic member with the opposing surface of the outer ring and the stationary system member. Driving force transmission device.   The frictional resistance applying means is formed by fitting a friction plate on the outer periphery of the end of the cage, applying an elastic force of an elastic member to one side surface of the friction plate, and forming the opposite side surface on the outer periphery of the cage. The friction plate is fixed to a housing that covers the whole of the two-way clutch, and the friction plate is used as a stationary system member, and the stationary system member is connected to the outer ring via a rotation resistance applying means. The driving force transmission device for a hybrid vehicle according to claim 1 or 2, wherein the rotational resistance applied is set to a value smaller than the rotational resistance applied to the cage from the frictional resistance applying means.   The driving force transmission device for a hybrid vehicle according to claim 1, wherein the stationary member is a housing.   The two-way clutch incorporates two cages having different diameters between the cylindrical inner surface of the outer ring and the cylindrical outer surface of the inner ring, and fixes the outer cage having a large diameter to the cylindrical inner surface of the outer ring. And a small-diameter inner cage are provided with radially opposing pockets, and a sprag and an elastic member that holds the sprag at a substantially central position in the circumferential direction of the pocket are incorporated into the pocket to hold the inner cage with respect to the outer cage. The hybrid according to any one of claims 1 to 4, comprising a sprag type two-way clutch in which the sprag is tilted by relative rotation of the device and engaged with the cylindrical inner surface of the outer ring and the cylindrical outer surface of the inner ring. Vehicle driving force transmission device.   The two-way clutch incorporates an inner ring on the inner side of the outer ring, and a cam surface is provided on the inner periphery of the outer ring that forms a narrow wedge-shaped space between the inner ring and the cylindrical outer surface of the inner ring. And a roller type two-way clutch in which a roller incorporated between the outer ring and the cylindrical outer surface is held by a cage, and the roller is engaged with the cam surface and the cylindrical outer surface by relative rotation of the cage with respect to the outer ring. Item 5. The driving force transmission device for a hybrid vehicle according to any one of Items 1 to 4.

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