JP2010018101A - Driving force transmission device for hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a problem that a two-way clutch is switched to an engagement state in the reverse direction from an engagement state before an electric motor stops, owing to vibration or the like when the electric motor stops. <P>SOLUTION: The driving force transmission device for the hybrid vehicle includes: a front wheel rotated and driven by an engine as a drive source; and a rear wheel using an electric motor as a drive source, the rear wheel rotated and driven through a gear speed reduction mechanism having a plurality of speed reduction parts for reducing the speed of rotation of an output shaft of the electric motor. The device incorporates a two-way clutch in a speed reduction part A<SB>2</SB>of the gear speed reduction mechanism so as to prevent rotation torque from being transmitted from the rear wheel to the electric motor when the vehicle travels by the drive of the engine. A rotation sensor 35 is incorporated into a rolling bearing 23 rotatably supporting a first shaft 21 of the gear speed reduction mechanism. <P>COPYRIGHT: (C)2010,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.

  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, an engine and an electric motor are mounted on a vehicle, and the rotation of the engine is transmitted to driving wheels via a transmission and a differential. Further, the rotation of the output shaft of the electric motor is decelerated by a speed reduction mechanism having a plurality of speed reduction parts and transmitted to the auxiliary drive wheel. A directional clutch is incorporated, and the two-way clutch is disengaged during normal driving by driving the engine, so that transmission of rotational torque from the auxiliary drive wheels to the reduction gear side is cut off.

  Here, in the two-way clutch, two cages having different diameters are incorporated between an input gear and a rotary shaft that is disposed so as to be rotatable relative to the input gear, and the outer cage is connected to the input gear. Fixing to the cylindrical inner surface, forming a radially opposing pocket in the outer cage and the inner cage, incorporating a sprag in the pocket, and tilting the sprag by relative rotation of the outer cage and the inner cage. The sprag is a sprag type two-way clutch in which the sprag is engaged with the cylindrical inner surface of the input gear and the cylindrical outer surface of the rotary shaft.

Japanese Patent No. 3408431

  By the way, in the driving force transmission apparatus for a hybrid vehicle described in Patent Document 1, when the electric motor is stopped and the output shaft of the electric motor rotates due to vibration or the like during forward traveling by driving the engine, the rotation of the electric motor rotates. 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.

  Even when the electric motor is stopped and the engine is driven backward, when the output shaft of the electric motor rotates due to vibration or the like, the sprag tilting to the reverse side switches to the forward side as described above. Thus, the engaged state is established, and the rotation of the auxiliary drive wheel is transmitted to the speed reducer, and the rotation of the auxiliary drive wheel is impeded.

  An object of the present invention is to prevent the occurrence of inconvenience that the two-way clutch is switch-engaged in the opposite direction from the engagement state before the electric motor is stopped due to vibration or the like when the electric motor is stopped. An object of the present invention is to provide a driving force transmission device for a hybrid vehicle.

  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 a plurality of speed reducers that use the electric motor as a drive source and decelerate rotation of the output shaft of the electric motor. An auxiliary drive wheel that is rotationally driven via a gear reduction mechanism, and a two-way clutch is incorporated in a reduction part located on the upstream side of torque transmission with respect to the final reduction part of the gear reduction mechanism. In an input gear, a rotary shaft that is disposed so as to be rotatable relative to the input gear, a cage that is disposed between opposing surfaces of the rotary shaft and the input gear, and a pocket that is formed in the cage. Built-in mechanical type that has an engagement element that engages the opposing surface of the input gear and the rotating shaft by relative rotation of the cage with respect to the input gear, and transmits the rotation of the input gear to the rotating shaft. In the driving force transmission device in the hybrid vehicle, each of the plurality of torque transmission shafts that transmit the rotation of the electric motor to the input gear of the two-way clutch is rotatably supported by a rolling bearing, and any one of the plurality of rolling bearings. A configuration was adopted in which a rotation sensor for detecting whether or not the torque transmission shaft was rotated in the opposite direction to the rotation direction before stopping after the electric motor stopped was adopted in one bearing.

  In the driving force transmission device for a hybrid vehicle having the above-described configuration, the electric motor is stopped, and the output shaft of the electric motor is in a direction opposite to the rotation direction before the stop due to vibration or the like when the vehicle is driven by the engine. Since the rotation sensor detects the rotation and outputs a signal, the output signal from the rotation sensor can rotate the electric motor in the rotation direction before stopping, and the two-way clutch is connected to the electric motor. It is possible to prevent the occurrence of inconvenience that the switch is engaged in the reverse direction from the engaged state before the stop.

  Here, the torque transmission shaft may be an output shaft of the electric motor, or may be a rotation shaft incorporated in each of the plurality of reduction units. Further, the rotation sensor may be a rotation sensor capable of detecting the origin position.

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

  The switch mechanism for rotating the cage of the two-way clutch relative to the input gear to displace the engagement element to the engagement position is a gear that is rotatably supported on the outer periphery of the end of the cage and transmits the rotation to the input gear. And a sub gear whose number of teeth is greater than that of the input gear, and an elastic member that presses the sub gear against a flange formed on the outer periphery of the cage, or the end of the cage Even if it consists of a friction plate rotatably supported on the outer periphery and prevented from rotating by a fixture fixed to a stationary member, and an elastic member that presses the friction plate against a flange formed on the outer periphery of the cage Good.

  As described above, in the present invention, when the electric motor is stopped and the output shaft of the electric motor rotates in a direction opposite to the rotation direction before the stop by vibration or the like in the running state of the vehicle driven by the engine, Since the rotation sensor detects the rotation and outputs a signal, it is possible to rotate the electric motor in the rotation direction before stopping, and the two-way clutch switches in the opposite direction from the engaged state before stopping the electric motor. It is possible to prevent the inconvenience of being engaged.

  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 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 16 a of the electric motor 16 is decelerated by the gear reduction mechanism 17 and transmitted to the rear wheel 12 via the two-way clutch 18 and the differential 19.

  As shown in FIG. 2, the electric motor 16 is supported by a housing 20, and a rolling bearing 16 b that rotatably supports an output shaft 16 a of the electric motor 16 is incorporated in the housing 20.

  Further, the gear reduction mechanism 17 for reducing the rotation of the output shaft 16 a of the electric motor 16 and transmitting it to the two-way clutch 18 is incorporated in the housing 20. The gear reduction mechanism 17 has a first shaft 21 arranged in parallel to the output shaft 16 a of the electric motor 16 and a second shaft 22 as a rotation shaft, and both ends of the first shaft 21 and the second shaft 22. The part is rotatably supported by rolling bearings 23 and 24.

Moreover, gear reduction mechanism 17 includes a first decelerating portion A ₁ to transmit to the first shaft 21 by decelerating the rotation of the output shaft 16a of the electric motor 16, the second shaft by decelerating the rotation of the first shaft 21 a second reduction unit a ₂ for transmitting to 22, and a third reduction portion a ₃ that transmits by decelerating the rotation of the second shaft 22 to the differential case 25 of the differential 19.

Here, the first reduction gear part A ₁ is configured such that a small diameter gear 26 is provided on the output shaft 16 a of the electric motor 16 and a large diameter gear 27 that meshes with the small diameter gear 26 is provided on the first shaft 21.

The second decelerating portion A ₂ is a small-diameter gear 28 provided on the first shaft 21, consists of the large-diameter gear 29 serving as a input gear in mesh with the small diameter gear 28, the rotation of the large gear 29 Transmission is made to the second shaft 22 via the two-way clutch 18.

Further, the third reduction unit A ₃ is a small-diameter gear 30 provided on the second shaft 22, is a structure in which a large-diameter gear 31 which meshes with the small gear 30 to the differential case 25, rotation of the differential case 25 is It is transmitted to the axle 33 of the rear wheel 12 via the differential mechanism 32.

  As shown in FIGS. 3 and 4, the two-way clutch 18 incorporates two cages 40 and 41 having different diameters into a large-diameter gear 29 as an input gear, and the outer cage 40 is connected to the large-diameter gear 29. A plurality of pockets 43 and 44 fixed to the cylindrical inner surface 42 and radially opposed to the outer retainer 40 and the inner retainer 41 are formed at intervals in the circumferential direction, and the pockets 43 and 44 facing the radial direction are formed. In addition, the sprag 45 is held at a substantially central position in the circumferential direction of the pocket 44 by the elastic member 46 built in the pocket 44 of the inner holder 41, and the outer holder 40 and the inner holder 41 are connected to each other. The sprag 45 is tilted by relative rotation, and the forward rotation cam surface 45 a or the reverse rotation cam surface 45 b formed at both ends is engaged with the cylindrical inner surface 42 of the large-diameter gear 29 and the cylindrical outer surface 47 of the second shaft 22. Allowed, through the sprag 45, so as to transmit rotational torque between the large gear 29 mutual second axis 22.

  Here, the inner cage 41 is rotatably supported on the second shaft 22 by a bearing 48 shown in FIG. A switch pin 49 extending radially outward is fixed to the inner holder 41, and the switch pin 49 is inserted into a long hole 50 formed in the outer holder 40 in the circumferential direction. The outer retainer 40 and the inner retainer 41 are relatively rotatable within a range in contact with both circumferential ends of the long hole 50.

  As shown in FIG. 3, one end portion of the inner cage 41 is located outside the end portion of the outer cage 40, and a flange 51 and a cylindrical surface 52 are formed on the outer periphery of one end portion of the inner cage 41, An engagement groove 53 is provided in the cylindrical surface 52.

  A sub gear 54 is rotatably fitted to the cylindrical surface 52, and the sub gear 54 is pressed against the flange 51 by an elastic member 55 such as a disc spring incorporated in the engaging groove 53.

  The sub gear 54 meshes with the small diameter gear 28 of the first shaft 21, and the number of teeth on the outer periphery is larger than the number of teeth on the large diameter gear 29. For this reason, when the small-diameter gear 28 rotates, the sub-gear 54 rotates behind the large-diameter gear 29 while sliding at the contact portion with the flange 51.

  As shown in FIG. 3, a rotation sensor 35 is incorporated between the outer race ring 23 a and the inner race ring 23 b of the rolling bearing 23 that rotatably supports the first shaft 21. The rotation sensor 35 detects whether or not the first shaft 21 rotates in the reverse direction with respect to the rotation direction before the stop when the electric motor 16 is stopped, and outputs a signal when the rotation is reversed. Yes.

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 output shaft 16a of the electric motor 16 is transmitted to the first shaft 21 via a first reduction portion A _1, transmission from the small diameter gear 28 provided on the first shaft 21 to the large diameter gear 29 and the sub gear 54 Is done.

  For this reason, the large-diameter gear 29 and the sub-gear 54 rotate in the same direction, and the inner cage 41 also rotates in the same direction as the large-diameter gear 29 due to the contact between the sub-gear 54 and the flange 51.

  At this time, since the number of teeth of the sub-gear 54 is larger than the number of teeth of the large-diameter gear 29, the sub-gear 54 rotates behind the large-diameter gear 29 while slipping at the contact portion with the flange 51, and is fixed to the large-diameter gear 29. The outer retainer 40 and the inner retainer 41 are rotated relative to each other.

  Due to the relative rotation of the outer retainer 40 and the inner retainer 41, the sprags 45 are tilted in the rotational direction of the outer retainer 40, and as shown in FIG. Engage with the cylindrical outer surface 47 of the shaft 22.

  When the outer cage 40 and the inner cage 41 rotate relative to each other by a predetermined angle, one end of the long hole 50 formed in the outer cage 40 comes into contact with the switch pin 49, and the rotation of the outer cage 40 moves from the switch pin 49 to the inside. The inner cage 41 is transmitted to the cage 41 and rotates integrally with the outer cage 40, and the sprag 45 is held in the engaged state. Further, the sub-gear 54 rotates while slipping at the contact portion with the flange 51.

By the engagement of the sprag 45 in the two-way clutch 18, the rotation of the large diameter gear 29 is transmitted to the second shaft 22 through the sprag 45. The rotation of the second shaft 22 is transmitted to the differential case 25 is decelerated by the third reduction portion A _3, rotates the rear wheel 12 is transmitted to the axle 33 shown in FIG. 1 via a differential mechanism 32, the vehicle Runs.

  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 second shaft 22, but the rotation of the second shaft 22 is in the idling direction with respect to the sprag 45. The rotation of 22 is not transmitted to the large-diameter gear 29, and the second shaft 22 rotates freely.

  Here, when the electric motor 16 is stopped and the output shaft 16a of the electric motor 16 rotates in a direction opposite to the rotation direction before the stop due to vibration or the like in the running state of the vehicle driven by the engine 13, the forward side or The sprag 45 tilted backward is switched to the reverse side or forward side to be engaged, and the rotation of the auxiliary drive wheel 12 is transmitted to the gear reduction mechanism 17 side, and the rotation of the auxiliary drive wheel 12 is obstructed. This causes a malfunction.

  However, in the embodiment, as shown in FIG. 3, since the rotation sensor 35 is incorporated in the rolling bearing 23 that rotatably supports the first shaft 21, the output shaft 16a of the electric motor 16 is not yet stopped. When rotating in the direction opposite to the rotation direction, the rotation sensor 35 detects the rotation and outputs a signal. Therefore, the output signal from the rotation sensor 35 can rotate the electric motor 16 in the rotation direction before the stop, and the two-way clutch is switched in the opposite direction from the engagement state before the electric motor 16 is stopped. It is possible to prevent the occurrence of inconvenience.

  In the embodiment, the rotation sensor 35 is incorporated in the rolling bearing 23 that rotatably supports the first shaft 21, but the rotation sensor 35 is disposed in the rolling bearing 16 b that rotatably supports the output shaft 16 a of the electric motor 16. Alternatively, the output shaft 16a may be rotatably supported by a sensor-equipped rolling bearing capable of detecting the origin position where the rotation sensor 35 is incorporated.

  In the embodiment shown in FIG. 3, the sub-gear 54 is used as a switch mechanism for rotating the inner cage 41 relative to the large-diameter gear 29 as the input gear to displace the sprag 45 to the engagement position. Although shown, the switch mechanism is not limited to this.

  For example, as shown in FIG. 5, instead of the sub gear 54, a friction plate 56 is rotatably fitted to a cylindrical surface 52, and the friction plate 56 is pressed against the flange 51 by an elastic member 55, while A fixing tool 57 is attached, a notch 58 is provided at the tip of the fixing tool 57 facing the friction plate 56, and a non-rotating piece 59 formed on the outer periphery of the friction plate 56 is fitted into the notch 58. The friction plate 56 may be prevented from rotating.

  Further, in the embodiment shown in FIG. 3, the sprag type is shown as the two-way clutch 18, but as shown in FIGS. 6 (I) and (II), it is fixed to the inner diameter surface of the large-diameter gear 29. A cam surface 71 is provided on the inner diameter surface of the outer ring 70 to form a wedge-shaped space between the cylindrical outer surface 47 of the second shaft 22 and the opposing space gradually decreases toward both ends in the circumferential direction. A pocket 73 is formed in the cage 72 that is installed between the opposing surfaces of the two shafts 22 so as to oppose the cam surface 71, and a roller 74 and the roller 74 in the pocket 73 are provided in the circumferential direction of the pocket 73. A roller-type two-way clutch 18 incorporating an elastic member 75 held in the center may be used.

  In the roller type two-way clutch 18, a switch pin 76 facing radially outward is fixed to the retainer 72, and the switch pin 76 is inserted into a long hole 77 formed in the outer ring 70. The outer ring 70 and the retainer 72 are relatively rotatable within a range in which the switch pin 76 abuts both ends thereof.

  In the use of the roller type two-way clutch 18 as described above, the sub gear 54 is rotatably fitted to the end of the cage 72, and the sub gear 54 is a flange provided on the cage 72 by the elastic member 55. 78, and when rotating torque is transmitted from the small diameter gear 28 to the large diameter gear 29, the outer ring 70 and the retainer 72 are relatively rotated so that the roller 74 is engaged with the cam surface 71 and the cylindrical outer surface 47. To do.

Overall configuration diagram showing an embodiment of a driving force transmission device in a hybrid vehicle according to the present invention Sectional drawing which shows the deceleration mechanism part which decelerates rotation of the electric motor shown in FIG. 1, and transmits to a rear-wheel. 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 sprags. Sectional drawing which shows the other example of the switch mechanism which switches a two-way clutch (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 16a output shaft 17 gear reduction mechanism _{A 1} first reduction portion _{A 2} second decelerating portion _{A 3} the third reduction unit 18 two-way clutch 20 housing (stationary member)
21 1st axis (torque transmission axis)
22 Second axis (rotary axis)
23 Rolling bearing 29 Large diameter gear (input gear)
35 Rotation sensor 40 Outer cage 41 Inner cage 43 Pocket 44 Pocket 45 Sprag (engagement element)
54 Sub gear 55 Elastic member 56 Friction plate 57 Fixture 72 Cage 73 Pocket 74 Roller (engagement element)

Claims (6)

A driving wheel that is rotationally driven using an engine as a driving source, and an auxiliary driving wheel that is rotationally driven via a gear reduction mechanism that has an electric motor as a driving source and has a plurality of reduction gears that decelerate the rotation of the output shaft of the electric motor. The two-way clutch is incorporated in the speed reduction part located upstream of the final speed reduction part of the gear reduction mechanism, and the two-way clutch can rotate relative to the input gear and the input gear. A rotary shaft that is disposed through the cage, a cage that is disposed between the opposed surfaces of the rotary shaft and the input gear, and a pocket formed in the cage, and the relative rotation of the cage with respect to the input gear. In a driving force transmission device in a hybrid vehicle composed of a mechanical type that has an engagement element that engages the opposing surfaces of an input gear and a rotating shaft and transmits the rotation of the input gear to the rotating shaft. Te,
Each of a plurality of torque transmission shafts that transmit rotation of the electric motor to the input gear of the two-way clutch is rotatably supported by a rolling bearing, and after stopping the electric motor on any one of the plurality of rolling bearings, A driving force transmission device in a hybrid vehicle, wherein a rotation sensor for detecting whether or not the torque transmission shaft rotates in a direction opposite to a rotation direction before stopping is assembled.   The driving force transmission device for a hybrid vehicle according to claim 1, wherein the rotation sensor is a rotation sensor capable of detecting an origin position.   The driving force transmission device for a hybrid vehicle according to claim 1, wherein the two-way clutch is a sprag type clutch having a sprag as an engagement element.   The driving force transmission device for a hybrid vehicle according to claim 1 or 2, wherein the two-way clutch is a roller type clutch having a roller as an engagement element.   A switch mechanism for rotating the cage relative to the input gear to displace the engagement element to the engagement position meshes with a gear that is rotatably supported on the outer periphery of the end of the cage and transmits the rotation to the input gear. The hybrid vehicle according to any one of claims 1 to 4, further comprising: a sub gear whose number of teeth is greater than that of the input gear; and an elastic member that presses the sub gear against a flange formed on an outer periphery of the cage. Driving force transmission device.   A switch mechanism for rotating the cage relative to the input gear to displace the engagement element to the engagement position is rotatably supported on the outer periphery of the end of the cage, and is prevented from rotating by a fixture fixed to the stationary member. The driving force transmission device in a hybrid vehicle according to any one of claims 1 to 4, further comprising: a friction plate that is formed, and an elastic member that presses the friction plate against a flange formed on an outer periphery of the cage.

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