JP2019078324A - Power transmission device for vehicle - Google Patents

Abstract

To provide a power transmission device for a vehicle which can install damper mechanisms for reducing a variation of a drive reaction force applied from wheel sides or vibration to the power transmission device for the vehicle without enlarging a size of the power transmission device for the vehicle as a whole.SOLUTION: A power transmission device for a vehicle comprises: a power source output shaft 12 for outputting a drive force of a power source 11; an intermediate shaft 13; wheel drive shafts 16a, 16b for driving left and right drive wheels 14a, 14b; a reduction gear mechanism 19 having a first reduction gear pair 17 constituted of a small-diameter side gear 23 arranged at the drive source output shaft 12, and a large-diameter side gear 24 arranged at the intermediate shaft 13, and a second reduction gear pair 18 constituted of a small-diameter side gear 25 arranged at the intermediate shaft 13, and a large-diameter side gear 26 arranged at the wheel drive shafts 16a, 16b; and damper mechanisms 20, 20A arranged at the intermediate shaft 13, and reducing a variation of a drive reaction force applied from the drive wheel 14a, 14b sides, or vibration.SELECTED DRAWING: Figure 1

Description

  The present invention is used in a vehicle, and includes a power source output shaft for outputting driving force of a power source, an intermediate shaft disposed parallel to the power source output shaft, and left and right drive wheels disposed parallel to the intermediate shaft. Provided between the intermediate shaft and the wheel drive shaft, and the first reduction gear pair (for example, counter drive gear and counter driven gear) provided between the power source output shaft and the intermediate shaft. And a reduction gear mechanism having a second reduction gear pair (for example, a final drive gear and a final driven gear).

  According to Patent Document 1, in such a power transmission apparatus for a vehicle, a reduction gear mechanism and a differential mechanism provided between the left and right driving wheels and capable of providing a rotational speed difference between the left and right wheels are provided. It has been shown that a power connection and disconnection mechanism for connecting and disconnecting the driving force can be provided integrally with the differential mechanism.

International Publication 2016/066215

  However, in the power transmission apparatus for vehicles of Patent Document 1 described above, the power transmission / reception mechanism is integrally provided with the differential mechanism, so that the entire power transmission apparatus for vehicles is enlarged. The reasons are shown below.

  In a power transmission apparatus for a vehicle, a differential mechanism and an intermediate shaft of a reduction gear mechanism are disposed in parallel, and on the intermediate shaft, a final drive gear meshing with a final driven gear having a large diameter of the differential mechanism and a power source output shaft It is necessary to provide a counter driven gear which is a large diameter side meshing with the counter drive gear.

  As a result, since a large diameter counter driven gear is present on the side of the differential mechanism, the large diameter counter driven gear interferes when a new mechanism is arranged coaxially with the wheel drive shaft of the differential mechanism. Become.

  In order to avoid interference by this large diameter counter driven gear and provide a power connection and disconnection mechanism in the vehicle power transmission device, the axial length of the intermediate shaft is increased and the large diameter counter driven gear is disposed apart from the side of the differential mechanism. Alternatively, a large diameter counter-driven gear may be arranged with the intermediate shaft further away from the wheel drive shaft of the differential mechanism, ie, the distance between the shafts may be increased.

  Therefore, in the case of the former, the axial length of the intermediate shaft becomes long, and in the case of the latter, the distance between the intermediate shaft and the wheel drive shaft of the differential mechanism becomes large. Do.

  On the other hand, in the above-described power transmission system for a vehicle, the impact torque applied to the power source from the drive wheel side caused by the unevenness of the road surface, for example, the fluctuation or vibration of the driving reaction force is generated between the reduction gear mechanism and the differential mechanism. There is a need for a damper mechanism to reduce. Then, it is desired that the damper mechanism be provided in the vehicle power transmission without increasing the size of the entire vehicle power transmission.

  The present invention can provide a damper mechanism for reducing the fluctuation or vibration of the drive reaction force applied from the wheel side in the vehicle power transmission device without enlarging the entire vehicle power transmission device. The purpose is to provide

  The power transmission apparatus for a vehicle according to the present invention includes a power source output shaft for outputting a driving force of a power source, an intermediate shaft disposed parallel to the power source output shaft, and a left and right disposed parallel to the intermediate shaft. A first reduction gear pair comprising a wheel drive shaft for driving the drive wheel, a small diameter gear provided on the power source output shaft, and a large diameter gear provided on the intermediate shaft; A reduction gear mechanism having a second reduction gear pair including a small diameter gear provided on an intermediate shaft and a large diameter gear provided on the wheel drive shaft; And a damper mechanism for reducing fluctuation or vibration of a drive reaction force applied from the drive wheel side.

  According to this, since the damper mechanism is provided on the intermediate shaft which is conventionally a dead space, the power transmission apparatus for a vehicle can increase the distance between the intermediate shaft and the wheel drive shaft without increasing the axial length of the intermediate shaft. Alternatively, the damper mechanism can be provided without increasing the size of the entire vehicle power transmission device.

BRIEF DESCRIPTION OF THE DRAWINGS It is the skeleton figure which showed the power transmission device for vehicles in 1st embodiment of this invention notionally. BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows the power transmission device for vehicles in 1st embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is an external view which partially opens and shows the power transmission apparatus for vehicles in 1st embodiment of this invention. It is the external view which looked at the power transmission device for vehicles shown in FIG. 3 from the reverse direction to FIG. It is a perspective view which shows the state before the assembly in the 1st Example of a damper mechanism. It is explanatory drawing which shows the state which hold | maintains the coiled spring of the damper mechanism of 1st Example to a holding part. It is a perspective view which shows the state which attached the coiled spring of the damper mechanism of 1st Example to a counter driven gear. It is sectional drawing which shows the attachment state of the damper mechanism of 1st Example. It is explanatory drawing explaining the relationship of arrangement | positioning of a coiled spring, a press part, and an attaching part. It is a perspective view which shows the state before the assembly in 2nd Example of a damper mechanism. It is a perspective view which shows the state which attached the coiled spring of the damper mechanism of 2nd Example to the counter driven gear. It is explanatory drawing which shows the state which the coil spring in the damper mechanism of 2nd Example attached to the counter driven gear. It is explanatory drawing which shows the other example of the rotation member of a damper mechanism. It is the skeleton figure which showed the power transmission device for vehicles in a second embodiment of the present invention notionally.

First Embodiment
Hereinafter, a first embodiment of a power transmission apparatus for a vehicle according to the present invention will be described with reference to the drawings.

  The power transmission system 10 for a vehicle shown in FIG. 1 includes a power source output shaft 12 for outputting the driving force of the power source 11, an intermediate shaft 13 disposed parallel to the power source output shaft 12, and a parallel shaft. And wheel drive shafts 16a, 16b arranged to drive the left and right drive wheels 14a, 14b.

  The vehicular power transmission device 10 is provided on the intermediate shaft 13 with a first reduction gear pair 17 constituted by a counter drive gear 23 provided on the power source output shaft and a counter driven gear 24 provided on the intermediate shaft 13. And a reduction gear mechanism 19 having a second reduction gear pair 18 composed of the final drive gear 25 and the final driven gear 26 provided on the wheel drive shafts 16a and 16b.

  The vehicle power transmission device 10 is provided with a damper mechanism 20 provided on the intermediate shaft 13 to reduce fluctuation or vibration of a drive reaction force applied from the drive wheels 14 a and 14 b to the power source 11.

  A commonly known differential mechanism 15 including a final driven gear 26 and provided between the left and right drive wheels 14a and 14b is connected to the wheel drive shafts 16a and 16b to provide a rotational speed difference to the left and right drive wheels 14a and 14b. It can be provided.

  As shown in FIG. 1, the aforementioned power source 11, power source output shaft 12, intermediate shaft 13, wheel drive shafts 16a and 16b, reduction gear mechanism 19, differential mechanism 15, and damper mechanism 20 are for vehicles. It is provided inside the casing 22 of the power transmission device 10. In addition. The wheel drive shafts 16a and 16b extend outward from the inner side of the casing 22, and drive wheels 14a and 14b are mounted at the extended ends thereof. The power source output shaft 12, the intermediate shaft 13, and the wheel drive shafts 16 a and 16 b are rotatably supported by the bearings 31, 32, 33 a and 33 b with respect to the casing 22.

<Power source>
The power source 11 is, for example, an electric motor, and the electric motor 11 includes a rotor 11 b that rotates with a stator 11 a as shown in FIG. 1, and the rotor 11 b is connected to the power source output shaft 12. Thus, the driving force of the electric motor 11 which is a power source is outputted from the power source output shaft 12, and the power source output shaft 12 rotates around the rotation axis r1.

  The power source output shaft 12 is hollow, and the wheel drive shaft 16a is inserted therein, and the power source output shaft 12 and the wheel drive shaft 16a are coaxially disposed. The power source is not limited to the electric motor, and may be an internal combustion engine.

<First reduction gear pair>
The first reduction gear pair 17 meshes with the counter drive gear 23 connected to the power source output shaft 12 so as to rotate integrally with the power source output shaft 12 as shown in FIG. And a counter driven gear 24 rotatably connected to the gear. The counter drive gear 23 rotates around the power source output shaft 12 (rotation axis r1), and the counter driven gear 24 rotates around the intermediate shaft 13 (rotation axis r2).

  Thus, the driving force from the power source output shaft 12 is transmitted to the intermediate shaft 13 via the counter drive gear 23 and the counter driven gear 24. The counter driven gear 24 is configured by a gear having a diameter larger than that of the counter drive gear 23.

<Second reduction gear pair>
As shown in FIG. 1, the second reduction gear pair 18 is disposed on one side (right side in FIG. 1) of the intermediate shaft 13 with respect to the first reduction gear pair 17. The second reduction gear pair 18 includes a final drive gear 25 connected to the intermediate shaft 13 so as to rotate integrally with the intermediate shaft 13, and a final driven gear 26 provided on the wheel drive shafts 16a and 16b and engaged with the final drive gear 25. , Is composed.

  The final driven gear 26 is connected to a generally known differential mechanism 15 and rotatably provided relative to the wheel drive shafts 16a and 16b. The final drive gear 25 rotates around the intermediate shaft 13 (that is, around the rotation axis r2), and the final driven gear 26 rotates around the rotation axis r1.

  In this manner, the driving force transmitted from the final drive gear 25 connected to the intermediate shaft 13 to the final driven gear 26 is transmitted to the wheel drive shafts 16 a and 16 b via the differential mechanism 15. The final driven gear 26 is configured by a gear larger in diameter than the final drive gear 25.

<Damper mechanism>
As shown in FIG. 1, the damper mechanism 20 is disposed on one side (right side in FIG. 1, right side of the rotation axis r 2) of the intermediate shaft 13 with respect to the counter driven gear 24 and the counter driven gear 24. And a rotary plate 27 rotatably provided around the intermediate shaft 13 (that is, around the rotation axis r2), and interposed between the counter driven gear 24 and the rotary plate 27 and between the counter driven gear 24 and the rotary plate 27. It is comprised by the coiled spring 28 which can be compressed by relative rotation.

  As shown in FIG. 1, the counter driven gear 24 is rotatably coupled to the intermediate shaft 13, and the rotating plate 27 is coupled to the intermediate shaft 13 so as to rotate integrally with the intermediate shaft 13.

  The damper mechanism 20 bends or compresses the coil spring 28 by the relative rotation between the counter driven gear 24 and the rotary plate 27 by driving the driving force of the power source output shaft 12 so that the driving force of the power source output shaft 12 becomes the counter driven gear 24. To the rotating plate 27.

  Further, the damper mechanism 20 is such that the impact torque applied to the electric motor 11 from the side of the drive wheels 14a and 14b caused by the unevenness of the road surface, for example, fluctuation or vibration of the drive reaction force relative rotation between the counter driven gear 24 and the rotating plate 27 Thus, the coil spring 28 can be flexed or compressed and reduced.

  Thus, as shown in FIG. 1, the counter driven gear 24, the rotating plate 27 and the coil spring 28 constituting the damper mechanism 20 constitute the conventional dead space of the counter driven gear 24, that is, the conventional dead space of the intermediate shaft 13. Provided in Thus, since the damper mechanism 20 is provided on the intermediate shaft 13 which is a conventional dead space, the vehicle power transmission device 10 does not need to increase the axial length of the intermediate shaft 13 or the intermediate shaft 13 and the wheel drive shafts 16a and 16b. The damper mechanisms 20 and 20A can be provided without increasing the distance between the shafts, that is, without increasing the size of the entire vehicle power transmission device 10.

  An example of implementation of this power transmission device 10 for vehicles is shown in FIG.2, FIG.3, FIG.4. The illustration of the drive wheels 14a and 14b is omitted in FIGS. 3 and 4.

  The damper mechanism 20 is provided on the counter driven gear 24 which is a gear on the large diameter side of the first reduction gear pair 17 provided on the intermediate shaft 13 as described above. Thereby, since the counter driven gear 24 is a gear pair most accelerated from the wheel drive shafts 16a and 16b, since the damper mechanism 20 can be used more compactly because of the small torque, it is advantageous in space. Yes, weight increase can also be suppressed.

(First embodiment of damper mechanism)
A first embodiment of the damper mechanism 20 will be described based on FIG. 5 to FIG.
The damper mechanism 20 is composed of the counter driven gear 24, the rotating plate 27 and the coil spring 28 as described above, and as shown in FIG. 8, the ring portion 13 a and the intermediate shaft extending radially from the intermediate shaft 13. The intermediate shaft 13 is provided so as to be interposed between the bearing 32 and the bearing 32.

  As shown in FIG. 8, the counter driven gear 24 is provided rotatably on the intermediate shaft 13 via a needle bearing (not shown), and the counter driven gear 24 rotates around the intermediate shaft 13 (rotation axis r2). .

  The rotating plate 27 is disposed on one side (the right side of FIG. 8 and the right side of the rotation axis r2) of the intermediate shaft 13 with respect to the counter driven gear 24 as shown in FIG. The rotary plate 27 is rotatably provided about the 13 rotations (rotation axis r2), and is connected to the intermediate shaft 13 so as to rotate integrally with the intermediate shaft 13 by press-fitting spline fitting or the like.

  The coil spring 28 is interposed between the counter driven gear 24 and the rotating plate 27, as shown in FIG. 8, and can be compressed by relative rotation between the counter driven gear 24 and the rotating plate 27. The counter driven gear 24 corresponds to any one of the first rotating member and the second rotating member in the present invention. The rotating plate 27 corresponds to either the first rotating member or the second rotating member in the present invention.

  As shown in FIG. 5 to FIG. 8, a pair of holding portions 51, 51 is provided in the plurality of (the four examples are shown in FIG. 5) coil springs 28. The holding portion 51 is provided at each end 28 c of the coil spring 28, and the end 28 c of the coil spring 28 extends in the radial direction of the coil spring 28 when the coil spring 28 is compressed by relative rotation between the counter driven gear 24 and the rotating plate 27. Regulate displacement. As shown in FIGS. 6 and 8, the holding portion 51 can be inserted and disposed in the end 28 c of the coil spring 28 and can be in contact with the in-contact portion 28 a (contacted portion) in the end 28 c. 51a and an abutting surface 51b that can abut on the end surface 28b of the coil spring 28. Therefore, the holding portion 51 can restrict displacement of the end 28 c of the coil spring 28 in the radial direction of the coil spring 28.

  The attachment portion 52 extends in the circumferential direction of the counter driven gear 24 or the rotary plate 27 as shown in FIG. 5 and one side of the counter driven gear 24 to the middle shaft 13 (a lower right side in FIG. 5 and a right side in FIG. 8) The counter driven gear 24 is erected so as to extend toward it.

  The holding portion 51 has a bottomed groove 51 c on the radial center of the coil spring 28. On the other side of the holding portion 51 (the back side of the convex portion 51a or the contact surface 51b), there is a bottomed groove 51c in which the holding portion 51 is fitted in the mounting portion 52 slidably in the circumferential direction of the counter driven gear 24 or the rotary plate 27 It is provided. As shown in FIG. 7, the bottomed groove 51 c of the holding portion 51 is fitted to the mounting portion 52, and the holding portion 51 is mounted to the mounting portion 52.

  The pair of holding portions 51 is provided at each end of one coil spring 28. Therefore, the damper mechanism 20 has four coil springs 28, and the pair of holding portions 51 is provided in four. The holding portion 51 alone has a total of eight. As shown in FIGS. 5 and 7, four mounting portions 52 are provided in the damper mechanism 20. On one mounting portion 52, as shown in FIG. 7, the holding portions 51 of the coil springs 28 adjacent to each other, that is, two pairs of holding portions 51 are mounted.

  A pressing portion 53 capable of pressing the end face 28 b of the coil spring 28 by relative rotation between the counter driven gear 24 and the rotation plate 27 is provided on the rotation plate 27. Four pressing portions 53 are provided in the damper mechanism 20 corresponding to four of the coil springs 28 of the damper mechanism 20. As shown in FIG. 9, the pressing portion 53 has one end in the radial direction of the coil spring 28 of the end face 28 b of the end 28 c of the coil spring 28 and the other end in the radial direction of the coil spring 28 directly or through the holding portion 51. Can be pressed.

  Thus, the end portion of the coil spring 28 can be uniformly pressed by the pressing portion 53 without being biased. Specifically, as shown in FIG. 9, the pressing portion 53 is the inside in the radial direction of the counter driven gear 24 of the end face 28 b of the coil spring 28 and the outside in the radial direction of the counter driven gear 24 of the end face 28 b of the coil spring 28. The leg 54 is capable of pressing the That is, the leg portion 54 is disposed on one side of the mounting portion 52 (inward in the radial direction of the counter driven gear 24) and the other side of the mounting portion 52 (inward of the radial direction of the counter driven gear 24) in the radial direction of the counter driven gear 24. Having a leg 54 formed.

  Specifically, as shown in FIG. 9, the leg portion 54 is provided on the first leg portion 54 a provided on one side of the mounting portion 52 and on the other side of the mounting portion 52 in the radial direction of the counter driven gear 24. And a second leg 54b. The mounting portion 52 can be positioned between the first leg 54a and the second leg 54b.

  The first leg 54a and the second leg 54b of the leg 54 are erected on the rotary plate 27 so as to extend toward the other of the intermediate shaft 13 (upper left in FIG. 5, left in FIG. 8). It is done. The first leg 54 a and the second leg 54 b have a bifurcated shape as shown in FIGS. 5 and 8. The attachment portion 52 can be positioned between the first leg 54a and the second leg 54b of the pressing portion 53, as shown in FIG.

  As a result, relative rotation between the rotary plate 27 and the counter driven gear 24 can be secured. The pressing portion 53 is provided such that the first leg portion 54a and the second leg portion 54b sandwich the mounting portion 52 in the radial direction of the counter driven gear 24 between the holding portions 51 and 51 of the coil springs 28 adjacent to each other. Be

  The pressing portion 53 is not limited to a bifurcated shape like the above-described leg portion 54, and it is apparent that another shape, for example, a single shape may be used.

  The operation of the damper mechanism 20 will be described below. When the driving force of the power source 11 is transmitted to the drive wheels 14a and 14b, that is, the driving force of the electric motor 11 is transmitted to the counter driven gear 24. The end face 28b of the end 28c on one side of the coil spring 28 is rotated by the mounting portion 52 through the holding portion 51, ie, the contact surface 51b, by the action of the mounting portion 52 accompanying the rotation of the counter driven gear 24 It is pressed by.

  On the other hand, the other end surface 28 b of the end portion 28 c of the coil spring 28 is pressed by receiving by the pressing portion 53 via the holding portion 51, and the coil spring 28 is compressed. Thus, the damper mechanism 20 transmits the driving force from the counter driven gear 24 to the rotating plate 27 by the compression of the coil spring 28 accompanying the rotation of the counter driven gear 24.

  Further, in the vehicle, for example, when the driving reaction force generated by the unevenness of the road surface is applied to the electric motor 11 from the driving wheels 14a and 14b side, the driving reaction force is applied to the counter driven gear 24 from the rotating plate 27. In this case, the pressing portion 53 directly presses the other end surface 28 b of the end portion 28 c of the coil spring 28 in the rotation direction of the rotation plate 27 by the action of the pressing portion 53 accompanying the rotation of the rotation plate 27.

  On the other hand, the end face 28 b of the end 28 c of the coil spring 28 is pressed by the attachment portion 52 via the holding portion 51, and the coil spring 28 is compressed. Thus, the damper mechanism 20 reduces the fluctuation or vibration of the driving reaction force from the rotating plate 27 to the counter driven gear 24 by the compression of the coil spring 28 accompanying the rotation of the rotating plate 27.

  In the case where the driving force of the power source output shaft 12 is transmitted toward the wheel drive shafts 16a and 16b via the intermediate shaft 13, the rotational direction of the counter driven gear 24 in the example shown in FIG. It is counterclockwise when viewed from the side.

  The counter driven gear 24 is configured by a helical gear. Specifically, as shown in FIG. 5, in the counter driven gear 24, the tooth 24 a is on one side of the intermediate shaft 13 (slant right lower side in FIG. 5) from the other side (diagonal left upper side in FIG. 5) of the intermediate shaft 13. It is a helical gear twisted on the rear side in the rotational direction.

  Sliding members abutting the counter driven gear 24 and the rotating plate 27 radially inward of the coil spring 28 between the counter driven gear 24 and the rotating plate 27 which are helical gears, for example, as shown in FIGS. 2 and 8 , Thrust bearings 41 or thrust washers. Thus, the vehicular power transmission device 10 prevents the occurrence of wear due to the contact between the counter driven gear 24 which is a helical gear and the rotary plate 27 by the thrust force of the helical gear acting on the rotary plate 27. be able to. The final drive gear 25 connected to the intermediate shaft 13 is also a helical gear, and the direction of the teeth 25a is the same as that of the counter driven gear 24.

  The distance between the holding portion 51 and the holding portion 51 constituting the pair of holding portions 51, that is, specifically, the contact surface 51b of the holding portion 51 and the holding portion 51 as shown in FIG. Based on the distance L between the surfaces 51b, it is possible to set a preload torque of the damper mechanism 20, that is, a torque which does not operate when the drive torque of the electric motor 11 is less than a predetermined torque. Thereby, the damper mechanism 20 can be set to a desired characteristic.

(Second embodiment of damper mechanism)
Next, a second embodiment of the damper mechanism will be described with reference to FIGS. The damper mechanism 20A of the second embodiment shown in FIG. 10 to FIG. It is shown.

  The damper mechanism 20A of the second embodiment differs from the damper mechanism 20 of the first embodiment only in that the holding portion 51 is integrally fixed to the mounting portion 52 as shown in FIGS. 10 and 12. Do. The remaining damper mechanism 20A configuration is similar to that of the above-described damper mechanism 20.

  In the damper mechanism 20A, as shown in FIGS. 10 and 12, the holding portion 51 is integrally fixed to the mounting portion 52. Specifically, the holding portions 51 of the coil springs 28 adjacent to each other, that is, two pairs of holding portions 51 are integrally fixed to one mounting portion 52.

  The end 28c of the coil spring 28 of the damper mechanism 20A and the contact portion 28a in the end 28c are all provided in the same manner as the damper mechanism 20. However, in the damper mechanism 20A, only one coil spring 28 among the four coil springs 28 is shown in FIG. 12, and the numbering of the other three coil springs 28 is omitted.

  The convex portion 51a of the holding portion 51 in the damper mechanism 20A of the second embodiment is formed in a tapered shape in which the outer diameter decreases toward the tip. Thereby, when the coiled spring 28 is compressed, the coiled spring can be compressed smoothly without being interfered by the convex portion 51a.

  The operation of the damper mechanism 20A will be described below. When the driving force of the power source 11 is transmitted to the drive wheels 14a and 14b, that is, the driving force of the electric motor 11 is transmitted to the counter driven gear 24. The end face 28b of the end 28c on one side of the coil spring 28 is rotated by the mounting portion 52 through the holding portion 51, ie, the contact surface 51b, by the action of the mounting portion 52 accompanying the rotation of the counter driven gear 24 It is pressed by.

  On the other hand, the other end surface 28b of the end portion 28c of the coil spring 28 is directly pressed by receiving by the pressing portion 53, and the coil spring 28 is compressed. Thus, the damper mechanism 20 transmits the driving force from the counter driven gear 24 to the rotating plate 27 by the compression of the coil spring 28 accompanying the rotation of the counter driven gear 24.

  Further, when a driving reaction force generated by the vehicle, for example, due to the unevenness of the road surface is applied to the electric motor 11 from the driving wheels 14a and 14b side, the driving reaction force is applied to the counter driven gear 24 from the rotating plate 27. In this case, the pressing portion 53 directly presses the other end surface 28 b of the end portion 28 c of the coil spring 28 in the rotation direction of the rotation plate 27 by the action of the pressing portion 53 accompanying the rotation of the rotation plate 27.

  On the other hand, the end face 28 b of the end 28 c of the coil spring 28 is pressed by the attachment portion 52 via the holding portion 51, and the coil spring 28 is compressed. Thus, the damper mechanism 20 reduces the fluctuation or vibration of the driving reaction force from the rotating plate 27 to the counter driven gear 24 by the compression of the coil spring 28 accompanying the rotation of the rotating plate 27.

  Another example of the rotating plate 27 used for the damper mechanisms 20 and 20A will be described with reference to FIG. In the rotation plate 27 shown in FIG. 13, a peripheral wall portion 55 extending along the circumferential direction from the outermost portion 53 a of the pressing portion 53 is provided. The peripheral wall 55 extends circumferentially outward in the radial direction from the outermost portion 53a and extends along the rotation axis r2 (shown in FIGS. 1 and 2) of the rotary plate 27, ie, upward in the drawing of FIG. Extend.

  As a result, when the damper mechanisms 20 and 20A remove the coil spring 28 from the mounting portion 52 for inspection or the like, the coil with the coil spring 28 in the radial direction of the rotary plate 27 exceeds the rotary plate 27 in the peripheral wall 55 The spring 28 can be prevented from coming off.

  In the example of the damper mechanism 20 and the damper mechanism 20A described above, the mounting portion 52 is provided on the counter driven gear 24 and the pressing portion 53 is provided on the rotating plate 27. However, without being limited to this example, it is apparent that the mounting portion 52 can be provided on the rotating plate 27 and the pressing portion 53 can be provided on the counter driven gear 24.

Second Embodiment
Next, a second embodiment of the power transmission apparatus for a vehicle according to the present invention will be described with reference to FIG. In the vehicle power transmission device 10A of the second embodiment shown in FIG. 14, the same members as the members shown in FIG. 1 are shown with the same reference numerals as the reference numerals shown in FIG.

  In the vehicle power transmission device 10A, as shown in FIG. 14, the power source output shaft 12 and the wheel drive shafts 16a and 16b are not coaxially arranged, and the wheel drive shafts 16a and 16b are power source output shafts. It differs from the power transmission system 10 for vehicles only in that it is provided apart from 12 and in parallel. The remaining configuration of the vehicle power transmission device 10A is the same as that of the vehicle power transmission device 10 shown in FIG.

  Accordingly, in the vehicle power transmission device 10A as well, the damper mechanisms 20 and 20A are provided on the intermediate shaft 13 in the same manner as the vehicle power transmission device 10. In the vehicle power transmission device 10A, it is apparent that the power source output shaft 12 may be solid or not hollow.

(Effect of the embodiment)
As described above, according to the vehicle power transmission devices 10 and 10A according to the first embodiment and the second embodiment of the present invention, the power source output shaft 12 for outputting the driving force of the power source 11 and the power source output An intermediate shaft 13 disposed parallel to the shaft 12, wheel drive shafts 16a and 16b disposed parallel to the intermediate shaft 13 for driving the left and right drive wheels 14a and 14b, and a small diameter provided on the power source output shaft 12 A first reduction gear pair 17 composed of a gear 23 on the side and a gear 24 on the large diameter side provided on the intermediate shaft 13, and a gear 25 on the small diameter side provided on the intermediate shaft 13 and wheel drive shafts 16a and 16b And a reduction gear mechanism 19 having a second reduction gear pair 18 configured by the large diameter side gear 26 provided on the drive shaft, and a driving reaction force provided on the intermediate shaft 13 and applied from the drive wheels 14a and 14b side Mechanism to reduce vibration or vibration It includes a 0,20A, a. Thus, since the damper mechanisms 20 and 20A are provided on the intermediate shaft 13 which is a conventional dead space, the vehicle power transmission device 10 or 10A does not need to increase the axial length of the intermediate shaft 13 or the intermediate shaft 13 and the wheel drive shaft The damper mechanisms 20 and 20A can be provided without increasing the distance between the shafts 16a and 16b, that is, without increasing the size of the entire vehicle power transmission device 10 or 10A.

  As described above, according to the vehicle power transmission devices 10 and 10A according to the first and second embodiments of the present invention, the damper mechanisms 20 and 20A are the gears on the large diameter side of the first reduction gear pair 17 Provided at 24. As a result, since the gear 24 on the large diameter side of the first reduction gear pair 17 is the gear pair most accelerated from the wheel drive shafts 16a and 16b, the damper mechanisms 20 and 20A are more Since the small size can be used, it is advantageous in space and can suppress the weight increase.

  As described above, according to the vehicle power transmission devices 10 and 10A according to the first and second embodiments of the present invention, the damper mechanisms 20 and 20A are the gears on the large diameter side of the first reduction gear pair 17 24, a gear 24 on the large diameter side of the first reduction gear pair 17, and a rotating member 27 rotatably provided about the intermediate shaft 13 on one side of the intermediate shaft 13, and the first reduction gear pair 17. It has a coil spring 28 interposed between the large diameter side gear 24 and the rotary member 27 and compressible by relative rotation between the large diameter side gear 24 of the first reduction gear pair 17 and the rotary member 27. The gear 24 on the large diameter side of the first reduction gear pair 17 is rotatably coupled to the intermediate shaft 13, and the rotating member 27 is coupled to the intermediate shaft 13 so as to rotate integrally with the intermediate shaft 13. Thus, the damper mechanisms 20 and 20A can be configured by the large diameter side gear 24 of the first reduction gear pair 17, the rotating member 27, and the coil spring 28, and the structure is simple.

  As described above, according to the power transmission device for vehicles 10 and 10A according to the first and second embodiments of the present invention, the large diameter side gear 24 of the first reduction gear pair 17 is a helical gear. A sliding member 41 is provided between the large diameter gear 24 of the first reduction gear pair 17 and the rotation member 27 and in contact with the large diameter gear 24 of the first reduction gear pair 17 and the rotation member 27. Thus, in the vehicle power transmission device 10, 10A, the thrust force from the helical gear 24 acts on the rotating member 27 to bring the large diameter gear 24 of the first reduction gear pair 17 into contact with the rotating member 27. Occurrence of wear due to

  As described above, according to the power transmission device 10 for a vehicle according to the first embodiment of the present invention, the power source output shaft 12 is hollow, and the wheel drive shafts 16 a and 16 b are provided inside the power source output shaft 12. The power source output shaft 12 and the wheel drive shafts 16a and 16b are coaxially arranged. Thus, since the power transmission device 10 for a vehicle is provided with the power source output shaft 12 and the wheel drive shafts 16a and 16b in an overlapping manner, the distance between the power source output shaft 12 and the wheel drive shafts 16a and 16b is narrowed. This makes it possible to miniaturize the power transmission device 10 for a vehicle.

  As described above, according to the power transmission device for vehicles 10 and 10A according to the first embodiment and the second embodiment of the present invention, the power source is the electric motor 11. Thus, the vehicle power transmission device 10, 10A can be used in a vehicle that can be driven by the electric motor 11.

  It should be noted that, when there are a plurality of embodiments, it is obvious that the characteristic parts of the respective embodiments can be combined as appropriate, unless otherwise specified.

10, 10A: Power transmission device for vehicle 11: Electric motor (power source)
12: power source output shaft 13: intermediate shaft 14: first rotors 14a, 14b: drive wheels 16a, 16b: wheel drive shaft 23: counter drive gear (gear on the small diameter side of the first reduction gear pair)
24: Counter driven gear (gear on the large diameter side of the first reduction gear pair)
25: Final drive gear (gear on the small diameter side of the second reduction gear pair)
26: Final driven gear (gear on the large diameter side of the second reduction gear pair)
17: first reduction gear pair 18: second reduction gear pair 19: reduction gear mechanism 20, 20A: damper mechanism 27: rotation plate (rotation member)
28: Coil spring

Claims (5)

A power source output shaft that outputs a driving force of the power source,
An intermediate shaft disposed parallel to the power source output shaft;
A wheel drive shaft disposed parallel to the intermediate shaft to drive left and right drive wheels;
A first reduction gear pair composed of a small diameter gear provided on the power source output shaft and a large diameter gear provided on the intermediate shaft; and a small diameter gear provided on the intermediate shaft A reduction gear mechanism having a second reduction gear pair configured of a large diameter gear provided on the wheel drive shaft;
A power transmission apparatus for a vehicle comprising: a damper mechanism provided on the intermediate shaft to reduce fluctuation or vibration of a driving reaction force applied from the drive wheel side.   The power transmission apparatus for a vehicle according to claim 1, wherein the damper mechanism is provided on a large diameter side gear of the first reduction gear pair.   The damper mechanism is rotatable on the large diameter side gear of the first reduction gear pair, the large diameter side gear of the first reduction gear pair on one side of the intermediate shaft, and rotatable about the intermediate shaft The relative rotation between the provided rotating member, the gear on the large diameter side of the first reduction gear pair, and the rotating member, the relative rotation between the gear on the large diameter side of the first reduction gear pair and the rotating member And the large diameter side gear of the first reduction gear pair is movably connected to the intermediate shaft, and the rotating member rotates integrally with the intermediate shaft on the intermediate shaft. The power transmission apparatus for a vehicle according to claim 2, wherein the power transmission apparatus is connected in order.   The large diameter side gear of the first reduction gear pair is a helical gear, and the large diameter side of the first reduction gear pair is between the large diameter side gear of the first reduction gear pair and the rotating member. 4. A power transmission apparatus for a vehicle according to claim 3, further comprising a sliding member which abuts on the gear and the rotating member.   The power source output shaft is hollow, and the wheel drive shaft is inserted into the power source output shaft, and the power source output shaft and the wheel drive shaft are coaxially arranged. The power transmission apparatus for a vehicle according to any one of the preceding claims.

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