JP2021187271A - Suspension device and motorcycle - Google Patents

Abstract

To provide a suspension device, etc. that are able to control inclination of two rear wheels through a simple configuration.SOLUTION: A suspension device includes: a first frame plate formed in a U-shape in a side view, and second and third frame plates that are arranged opposite a first surface and a second surface, respectively, of the first frame plate. A first through-hole and a second through-hole are formed in both ends, respectively, of the first frame plate, a third through-hole and a fourth through-hole are formed below the first through-hole and the second through-hole respectively, and pivot shafts are respectively arranged in the first through-hole to the fourth through-hole. The suspension device further includes: a first arm to a fourth arm, one ends of which are respectively rotatably connected to the pivot shafts arranged in the first through-hole to the fourth through-hole and the other ends of which are connected to the second frame plate; a fifth arm to an eighth arms, one ends of which are respectively rotatably connected to the pivot shafts arranged in the first through-hole to the fourth through-hole and the other ends of which are connected to the third frame; a first connection portion that connects the first arm and the second arm; and a second connection portion that connects the fifth arm and the sixth arm.SELECTED DRAWING: Figure 3

Description

The present technology relates to a suspension device that supports the rear wheels and an electric motorcycle provided with the suspension device.

Conventionally, a single-seater vehicle having one front wheel and two rear wheels has been proposed. The two rear wheels are connected by a link mechanism. The link mechanism is rotatably connected to the main body of the vehicle with the front-rear direction as the rotation axis direction. Due to the link mechanism, the two rear wheels tilt to the left and right with respect to the ground.

The link mechanism comprises a lean motor that rotates the link mechanism. The vehicle control device can determine the lean angle (inclination angle with respect to the ground) based on the handle angle and the vehicle speed, control the position of the rotation axis of the lean motor, and smoothly turn the vehicle (Patent Document 1). reference).

Japanese Unexamined Patent Publication No. 2017-178187

The control of the lean motor is complicated, and the burden on the control device is large. In addition, it is necessary to process the control device at high speed, and the manufacturing cost of the control device is high.

The present disclosure has been made in view of such circumstances, and an object of the present invention is to provide a suspension device and an electric motorcycle capable of controlling the inclination of two rear wheels with a simple configuration.

The suspension device according to the embodiment of the present disclosure has a U-shape in a side view, and is arranged opposite to a first frame plate having both ends protruding upward and one surface of the first frame plate, and is rear of the electric motorcycle. A second frame plate on which the wheels are supported and a third frame plate which is arranged to face the other surface of the first frame plate and supports the rear wheels of the electric motorcycle are provided at both ends of the first frame plate. A first through hole and a second through hole are formed, and a third through hole and a fourth through hole are formed below the first through hole and the second through hole in the first frame plate, and the first through hole is formed. A pivot axis extending in a direction parallel to the first frame plate and intersecting in the vertical direction is arranged in each of the through hole to the fourth through hole, and is arranged in the first through hole to the fourth through hole. The first arm to the fourth arm, one end of which is rotatably connected to each pivot and the other end of which is connected to the second frame plate, and each pivot arranged in the first through hole to the fourth through hole. The fifth arm to the eighth arm, one end of which is rotatably connected to the third frame plate and the other end of which is connected to the third frame plate, the first connecting portion connecting the first arm and the second arm, and the above. A second connecting portion for connecting the fifth arm and the sixth arm is provided.

In one embodiment of the present disclosure, the first arm to the fourth arm and the second frame plate rotate relative to each other. Further, the fifth arm to the eighth arm and the third frame plate rotate relatively. The second frame plate and the third frame plate rotate independently of each other. Further, the first arm and the second arm are connected by the first connecting portion, and the fifth arm and the sixth arm are connected by the second connecting portion.

The suspension device according to an embodiment of the present disclosure is a suspension that is arranged in a recess of the first frame plate having a U-shape in a side view and extends in the penetration direction of the first through hole to the fourth through hole, and the first. Each of the connecting portion and the second connecting portion is provided with a support portion that supports both ends of the suspension.

In one embodiment of the present disclosure, by providing a suspension between the first connecting portion and the second connecting portion, when the second frame plate or the third frame plate moves upward or downward, the suspension exerts an impact force. Absorb.

In the suspension device according to the embodiment of the present disclosure, an in-wheel motor is attached to the second frame plate and the third frame plate.

In one embodiment of the present disclosure, the use of an in-wheel motor eliminates the need to provide a motor, differential gear, axle, and the like, and increases the space for arranging the suspension device.

The electric motorcycle according to the embodiment of the present disclosure is arranged to face two rear wheels, a first frame plate having a U-shape in a side view, and both ends projecting upward, and one surface of the first frame. A second frame plate on which one rear wheel is supported and a third frame plate arranged opposite to the other surface of the first frame and supporting the other rear wheel are provided at both ends of the first frame plate. A first through hole and a second through hole are formed in the portion, and a third through hole and a fourth through hole are formed below the first through hole and the second through hole in the first frame plate. In each of the first through hole to the fourth through hole, a pivot axis extending in a direction parallel to the first frame plate and intersecting in the vertical direction is arranged, and is arranged in the first through hole to the fourth through hole. One end is rotatably connected to each of the pivots, and the other end is arranged in the first arm to the fourth arm connected to the second frame plate and the first through hole to the fourth through hole. A fifth arm to an eighth arm in which one end is rotatably connected to each pivot and the other end is connected to the third frame plate, and a first connecting portion connecting the first arm and the second arm. , A second connecting portion for connecting the fifth arm and the sixth arm.

In one embodiment of the present disclosure, the second frame plate can be rotated by the first arm to the fourth arm. Further, the third frame plate can be rotated by the fifth arm to the eighth arm. The second frame plate and the third frame plate rotate independently of each other. Further, the first arm and the second arm are connected by the first connecting portion, and the fifth arm and the sixth arm are connected by the second connecting portion.

In the suspension device and the electric motorcycle according to the embodiment of the present disclosure, the first arm to the fourth arm and the second frame plate can be relatively rotated. Further, the fifth arm to the eighth arm and the third frame plate can be relatively rotated. The second frame plate and the third frame plate rotate independently of each other. Further, the first arm and the second arm are connected by the first connecting portion, and the fifth arm and the sixth arm are connected by the second connecting portion. No motor is used, and there is no member connecting the 3rd arm and 4th arm, and no member connecting the 7th arm and 8th arm, and the inclination of the two rear wheels is controlled with a simple configuration. can do.

It is a schematic perspective view of an electric motorcycle. It is a schematic perspective view of a rear wheel mechanism. It is a schematic perspective view of a suspension system. It is a schematic front view of a suspension system. It is a schematic left side view of a suspension system. It is a schematic plan view of a suspension system. It is a schematic bottom view of the suspension system. It is a schematic right side view of the 1st frame plate. It is a right side sectional view which shows the structure in the vicinity of the 1st through hole substantially. It is a schematic perspective view of the rear wheel mechanism inclined to the left side. It is a schematic rear view of the rear wheel mechanism inclined to the left side.

Hereinafter, the present invention will be described with reference to the drawings showing the electric motorcycle according to the embodiment. FIG. 1 is a schematic perspective view of an electric motorcycle. In the following description, the top, bottom, front, back, left, and right in the figure are used. The electric motorcycle 1 includes a vehicle body frame (not shown), and the vehicle body frame is provided with a floor board 2, a front cover 3, a rear cover 4, a loading platform 6, a rear wheel 14, and the like. The floor board 2 extends in the horizontal direction. The front cover 3 has a cylindrical shape with the vertical direction as the axial direction, and protrudes upward from the front portion of the floor board 2. The rear cover 4 has a rectangular box shape and extends in the front-rear direction. The rear cover 4 projects upward from the rear portion of the floor board 2.

The two shafts 13a with the vertical direction as the axial direction are arranged inside the front cover 3 in a posture of being tilted slightly diagonally backward. A front suspension 13b is provided at the lower end of each shaft 13a, and the front wheels 13 are rotatably supported between the two front suspensions 13b. The upper ends of the two shafts 13a are attached to a steering portion 11 that can rotate around the axis of the shaft 13a, and two handles 10 project to the left and right from the steering portion 11. A brake lever 12 is attached to the lower side of the handle 10.

A seat 5 is provided on the upper surface of the rear cover 4. A secondary battery (not shown) is housed inside the rear cover 4. A connection port 16 is provided on the front surface of the rear cover 4. The secondary battery can be charged by connecting the plug of the charging stand to the connection port 16, for example.

A loading platform 6 is provided on the rear side of the seat 5. The loading platform 6 has a plate shape extending in the horizontal direction. Two rear wheels 14 are arranged below the loading platform 6. The rear wheel 14 includes an in-wheel motor 14a, a wheel 14b, and a tire 14c. An in-wheel motor 14a is arranged inside the wheel 14b, and a tire 14c is attached around the wheel 14b. The in-wheel motor 14a is driven by the electric power supplied from the secondary battery. Two mounting pipes 7 project upward from between the loading platform 6 and the seat 5. The two mounting pipes 7 are separated from each other in the left-right direction.

A roof 8 is provided above the floor board 2 and the seat 5. The roof 8 has a curved surface that protrudes upward, and is inclined so as to descend toward the front side. Two legs 8a project downward from the rear end of the roof 8. The two legs 8a are separated from each other in the left-right direction, and are attached to the two attachment pipes 7, respectively. A backrest 15 is provided between the mounting pipes 7 and between the legs 8a.

A transparent screen 9 projects upward from the upper part of the front cover 3. The upper end of the screen 9 is connected to the front end of the roof 8. The screen 9 is arranged in front of the handle 10 and the brake lever 12. A headlight device 20 is provided on the front surface of the front cover 3.

FIG. 2 is a schematic perspective view of the rear wheel mechanism 60. The rear wheel mechanism 60 is arranged below the loading platform 6. As shown in FIG. 2, the rear wheel mechanism 60 includes a suspension device 30, a lock mechanism 50, and a rear wheel 14. In FIG. 2, the description of the wheel 14b and the tire 14c is omitted. The lock mechanism 50 is attached to the suspension device 30 and regulates the rotation of the suspension device 30 by operating a lever (not shown) provided in the driver's seat.

3 is a schematic perspective view of the suspension device 30, FIG. 4 is a schematic front view of the suspension device 30, FIG. 5 is a schematic left side view of the suspension device 30, and FIG. 6 is a schematic view of the suspension device 30. A plan view, FIG. 7 is a schematic bottom view of the suspension device 30, and FIG. 8 is a schematic right side view of the first frame plate.

The suspension device 30 includes a first frame plate 31. The first frame plate 31 is connected to the vehicle body frame. One side of the first frame plate 31 faces the right side, and the other side faces the left side. As shown in FIG. 8, the first frame plate 31 has a U shape when viewed from the left-right direction, and both ends thereof project upward. A first through hole 31a penetrating in the left-right direction is formed in the front upper end portion of the first frame plate 31, and a second through hole 31b penetrating in the left-right direction is formed in the rear upper end portion.

A third through hole 31c penetrating in the left-right direction is formed on the lower side of the first through hole 31a in the first frame plate 31, and penetrates in the left-right direction on the lower side of the second through hole 31b in the first frame plate 31. The fourth through hole 31d is formed. A fifth through hole 31e penetrating in the left-right direction is formed between the third through hole 31c and the fourth through hole 31d. A recess 32 is formed between both ends of the first frame plate 31 and is located above the fifth through hole 31e.

A rectangular second frame plate 34 is arranged to face each other on one surface of the first frame plate 31, that is, the right surface. The second frame plate 34 extends back and forth. As shown in FIG. 3, the front upper corner portion and the rear upper corner portion of the second frame plate 34 project upward to form the protruding portions 34e, respectively. The front lower corner portion of the second frame plate 34 projects forward, and the rear lower corner portion projects rearward to form an overhanging portion 34d, respectively. The front overhang 34d is located on the front side of the front overhang 34e, and the rear overhang 34d is located on the rear side of the rear overhang 34e. The connecting shaft 34a projects to the right from the center of the right surface of the second frame plate 34. The connecting shaft 34a has a cylindrical shape, and the drive shaft of the in-wheel motor 14a is inserted into the connecting shaft 34a and fixed. The in-wheel motor 14a rotates around a drive shaft together with the wheel 14b and the tire 14c.

A connecting piece 34b is provided on each overhanging portion 34d and each protruding portion 34e. The connecting piece 34b projects to the right. As shown in FIG. 4, the two shaft portions 34c project forward from the two connecting pieces 34b arranged on the front side. As shown in FIG. 3, the two shaft portions 34c project rearward from the two connecting pieces 34b arranged on the rear side.

A first arm 41 is provided between the first through hole 31a and the connecting piece 34b arranged at the front upper corner of the second frame plate 34. The first arm 41 extends in the left-right direction. At the right end of the first arm 41, a tubular portion 41a having an axial direction in the front-rear direction is formed. As shown in FIG. 4, a bearing 41d is provided inside the tubular portion 41a. The bearing 41d rotatably supports the shaft portion 34c.

FIG. 9 is a cross-sectional view on the right side showing a configuration in the vicinity of the first through hole 31a. At the left end of the first arm 41, a tubular portion 41b having an axial direction in the front-rear direction is formed. The tubular portion 41b is arranged inside the first through hole 31a. Pillow balls 41c are coaxially provided inside the tubular portion 41b.

As shown in FIG. 9, on the front side of the first through hole 31a, the first frame plate 31 is formed with a through hole 31f penetrating in the front-rear direction. On the rear side of the first through hole 31a, the first frame plate 31 is formed with a screw hole 31g penetrating in the front-rear direction. The bolt 40a (axis) is inserted into the through hole 31f from the front side. A male screw is formed at the tip of the bolt 40a, and the male screw is connected to the screw hole 31g. The shaft portion of the bolt 40a is inserted into the pillow ball 41c provided in the tubular portion 41b. The right end portion of the first arm 41 is rotatably connected to the second frame plate 34 with the front-back direction as the rotation axis direction. The left end portion of the first arm 41 is rotatably connected to the first frame plate 31 via the pillow ball 41c with the front-back direction, the left-right direction, and the up-down direction as the rotation axis directions.

A second arm 42 is provided between the second through hole 31b and the connecting piece 34b arranged at the rear upper corner of the second frame plate 34. The second arm 42 extends in the left-right direction. At the right end of the second arm 42, a tubular portion 42a whose axial direction is the front-rear direction is formed. As shown in FIG. 3, a bearing 42c is coaxially provided inside the tubular portion 42a. The bearing 42c rotatably supports the shaft portion 34c.

At the left end of the second arm 42, a tubular portion 42b whose axial direction is the front-rear direction is formed. The tubular portion 42b is arranged inside the second through hole 31b. Pillow balls (not shown) are coaxially provided inside the tubular portion 42b.

On the rear side of the second through hole 31b, the first frame plate 31 is formed with a through hole (not shown) penetrating in the front-rear direction. On the front side of the second through hole 31b, the first frame plate 31 is formed with a screw hole (not shown) penetrating in the front-rear direction. The bolt 40a is inserted into the through hole from the rear side and connected to the screw hole. The shaft portion of the bolt 40a is inserted into the pillow ball provided in the tubular portion 42b. The right end portion of the second arm 42 is rotatably connected to the second frame plate 34 with the front-back direction as the rotation axis direction. The left end portion of the second arm 42 is rotatably connected to the first frame plate 31 via a pillow ball with the front-back direction, the left-right direction, and the up-down direction as rotation axis directions.

A third arm 43 is provided between the third through hole 31c and the connecting piece 34b arranged at the front lower corner of the second frame plate 34. As shown in FIG. 7, the third arm 43 has a crank shape and extends in the left-right direction. The right end portion of the third arm 43 is arranged in front of the left end portion of the third arm 43 and the right end portion of the first arm 41. At the right end of the third arm 43, a tubular portion 43a whose axial direction is the front-rear direction is formed. As shown in FIG. 4, the bearing 43d is coaxially provided inside the tubular portion 43a. The bearing 43d rotatably supports the shaft portion 34c.

At the left end of the third arm 43, a tubular portion 43b having an axial direction in the front-rear direction is formed. The tubular portion 43b is arranged inside the third through hole 31c. A pillow ball 43c is provided inside the tubular portion 43b.

Similar to the first through hole 31a, through holes and screw holes (both not shown) are formed in the first frame plate 31 on the front side and the rear side of the third through hole 31c. The bolt 40a is inserted into the through hole from the front side and connected to the screw hole. The shaft portion of the bolt 40a is inserted into the pillow ball 43c provided in the tubular portion 43b. The right end portion of the third arm 43 is rotatably connected to the second frame plate 34 with the front-back direction as the rotation axis direction. The left end portion of the third arm 43 is rotatably connected to the first frame plate 31 via the pillow ball 43c with the front-back direction, the left-right direction, and the up-down direction as the rotation axis directions.

A fourth arm 44 is provided between the fourth through hole 31d and the connecting piece 34b arranged at the rear lower corner of the second frame plate 34. As shown in FIG. 7, the fourth arm 44 has a crank shape and extends in the left-right direction. The right end portion of the fourth arm 44 is arranged behind the left end portion of the fourth arm 44 and the right end portion of the first arm 41. At the right end of the fourth arm 44, a tubular portion 44a having an axial direction in the front-rear direction is formed. As shown in FIG. 3, the bearing 44c is coaxially provided inside the tubular portion 44a. The bearing 44c rotatably supports the shaft portion 34c.

At the left end of the fourth arm 44, a tubular portion 44b having an axial direction in the front-rear direction is formed. The tubular portion 44b is arranged inside the fourth through hole 31d. A pillow ball (not shown) is provided inside the tubular portion 44b.

Similar to the second through hole 31b, screw holes and through holes (both not shown) are formed in the first frame plate 31 on the front side and the rear side of the fourth through hole 31d. The bolt 40a is inserted into the through hole from the rear side and connected to the screw hole. The shaft portion of the bolt 40a is inserted into the pillow ball provided in the tubular portion 44b. The right end portion of the fourth arm 44 is rotatably connected to the second frame plate 34 with the front-back direction as the rotation axis direction. The left end portion of the fourth arm 44 is rotatably connected to the first frame plate 31 via a pillow ball with the front-back direction, the left-right direction, and the up-down direction as rotation axis directions.

As shown in FIG. 5, a rectangular third frame plate 35 is arranged to face each other on the other surface of the first frame plate 31, that is, the left surface. The third frame plate 35 extends back and forth. The front upper corner portion and the rear upper corner portion of the third frame plate 35 project upward to form the projecting portions 35e, respectively. The front lower corner portion of the third frame plate 35 projects forward, and the rear lower corner portion projects rearward to form an overhanging portion 35d, respectively. The front overhang 35d is located on the front side of the front overhang 35e, and the rear overhang 35d is located on the rear side of the rear overhang 35e. The connecting shaft 35a projects to the right from the center of the left surface of the third frame plate 35. The connecting shaft 35a has a cylindrical shape, and the drive shaft of the in-wheel motor 14a is inserted into the connecting shaft 35a and fixed. The in-wheel motor 14a rotates around a drive shaft together with the wheel 14b and the tire 14c.

A connecting piece 35b is provided on each overhanging portion 35d and each protruding portion 35e. The connecting piece 35b projects to the left. As shown in FIG. 4, the two shaft portions 35c project forward from the two connecting pieces 35b arranged on the front side. As shown in FIG. 3, two shaft portions 35c project rearward from the two connecting pieces 35b arranged on the rear side.

A fifth arm 45 is provided between the first through hole 31a and the connecting piece 35b arranged at the front upper corner of the third frame plate 35. The fifth arm 45 extends in the left-right direction. At the left end of the fifth arm 45, a tubular portion 45a having an axial direction in the front-rear direction is formed. As shown in FIG. 4, a bearing 45d is provided inside the tubular portion 45a. The bearing 45d rotatably supports the shaft portion 35c.

As shown in FIG. 9, a tubular portion 45b having an axial direction in the front-rear direction is formed at the right end portion of the fifth arm 45. The tubular portion 45b is arranged inside the first through hole 31a and behind the tubular portion 41b of the first arm 41. The tubular portion 45b is arranged coaxially with the tubular portion 41b. A pillow ball 45c is provided inside the tubular portion 45b. The shaft portion of the bolt 40a is inserted into the pillow ball 45c provided in the tubular portion 45b. That is, the shaft portion of the bolt 40a is inserted into the tubular portions 41b and 45b of the first arm 41 and the fifth arm 45. The left end portion of the fifth arm 45 is rotatably connected to the third frame plate 35 with the front-back direction as the rotation axis direction. The right end portion of the fifth arm 45 is rotatably connected to the first frame plate 31 via the pillow ball 45c with the front-back direction, the left-right direction, and the up-down direction as the rotation axis directions.

A sixth arm 46 is provided between the second through hole 31b and the connecting piece 35b arranged at the rear upper corner of the third frame plate 35. The sixth arm 46 extends in the left-right direction. At the left end of the sixth arm 46, a tubular portion 46a having an axial direction in the front-rear direction is formed. As shown in FIG. 3, a bearing 46c is coaxially provided inside the tubular portion 46a. The bearing 46c rotatably supports the shaft portion 35c.

At the right end of the sixth arm 46, a tubular portion 46b having an axial direction in the front-rear direction is formed. The tubular portion 46b is arranged inside the second through hole 31b and behind the tubular portion 42b of the second arm 42. The tubular portion 46b is arranged coaxially with the tubular portion 42b. A pillow ball (not shown) is provided inside the tubular portion 46b. As described above, the bolt 40a is attached to the second through hole 31b. The shaft portion of the bolt 40a is inserted into the pillow ball of the tubular portion 42b of the second arm 42, and further inserted into the pillow ball (not shown) of the tubular portion 46b of the sixth arm 46. The left end portion of the sixth arm 46 is rotatably connected to the third frame plate 35 with the front-back direction as the rotation axis direction. The right end portion of the sixth arm 46 is rotatably connected to the first frame plate 31 via a pillow ball with the front-back direction, the left-right direction, and the up-down direction as rotation axis directions.

A seventh arm 47 is provided between the third through hole 31c and the connecting piece 35b arranged at the front lower corner of the third frame plate 35. As shown in FIG. 7, the seventh arm 47 has a crank shape and extends in the left-right direction. The left end portion of the 7th arm 47 is arranged in front of the right end portion of the 7th arm 47 and the left end portion of the 5th arm 45. A tubular portion 47a having an axial direction in the front-rear direction is formed at the left end portion of the seventh arm 47. As shown in FIG. 4, a bearing 47c is coaxially provided inside the tubular portion 47a. The bearing 47c rotatably supports the shaft portion 35c.

As shown in FIG. 7, a tubular portion 47b having an axial direction in the front-rear direction is formed at the right end portion of the seventh arm 47. The tubular portion 47b is arranged inside the third through hole 31c and behind the tubular portion 43b of the third arm 43. The tubular portion 47b is arranged coaxially with the tubular portion 43b. A pillow ball (not shown) is provided inside the tubular portion 47b. As described above, the bolt 40a is attached to the third through hole 31c. The shaft portion of the bolt 40a is inserted into the pillow ball of the cylinder portion 43b of the third arm 43, and further inserted into the pillow ball of the cylinder portion 47b of the seventh arm 47. The left end portion of the 7th arm 47 is rotatably connected to the 3rd frame plate 35 with the front-back direction as the rotation axis direction. The right end portion of the seventh arm 47 is rotatably connected to the first frame plate 31 via a pillow ball with the front-back direction, the left-right direction, and the up-down direction as rotation axis directions.

An eighth arm 48 is provided between the fourth through hole 31d and the connecting piece 35b arranged at the rear lower corner of the third frame plate 35. As shown in FIG. 7, the eighth arm 48 has a crank shape and extends in the left-right direction. The left end portion of the eighth arm 48 is arranged behind the right end portion of the eighth arm 48 and the left end portion of the sixth arm 46. A tubular portion 48a having an axial direction in the front-rear direction is formed at the left end portion of the eighth arm 48. As shown in FIG. 3, a bearing 48c is coaxially provided inside the tubular portion 48a. The bearing 48c rotatably supports the shaft portion 35c.

As shown in FIG. 3, a tubular portion 48b having an axial direction in the front-rear direction is formed at the right end portion of the eighth arm 48. The tubular portion 48b is arranged inside the fourth through hole 31d and behind the tubular portion 44b of the fourth arm 44. The tubular portion 48b is arranged coaxially with the tubular portion 44b. A pillow ball (not shown) is provided inside the tubular portion 48b. As described above, the bolt 40a is attached to the fourth through hole 31d. The shaft portion of the bolt 40a is inserted into the pillow ball of the cylinder portion 44b of the fourth arm 44, and further inserted into the pillow ball of the cylinder portion 48b of the eighth arm 48. The left end portion of the eighth arm 48 is rotatably connected to the third frame plate 35 with the front-back direction as the rotation axis direction. The right end portion of the eighth arm 48 is rotatably connected to the first frame plate 31 via a pillow ball with the front-back direction, the left-right direction, and the up-down direction as rotation axis directions.

As shown in FIGS. 3 and 6, the left-right central portion of the first arm 41 and the second arm 42 is connected by the first connecting rod 36. The first connecting rod 36 has a boomerang shape extending back and forth, and is arranged with the apex facing the right side. A storage portion 36a having a U-shape in a plan view is formed at the apex portion of the first connecting rod 36. The bottom of the U-shaped storage portion 36a is arranged on the right side, and both ends of the storage portion 36a are directed to the left side. A rubber bush 36b is stored in the storage portion 36a.

As shown in FIGS. 3 and 6, the left-right central portion of the fifth arm 45 and the sixth arm 46 is connected by a second connecting rod 37. The second connecting rod 37 has a boomerang shape extending back and forth, and is arranged with the apex facing the left side. A U-shaped storage portion 37a in a plan view is formed at the apex portion of the second connecting rod 37. The bottom of the U-shaped storage portion 37a is arranged on the left side, and both ends of the storage portion 37a are directed to the right side. A rubber bush 37b is stored in the storage portion 37a.

The rubber bush 36b of the first connecting rod 36 and the rubber bush 37b of the second connecting rod 37 face each other in the left-right direction through the recess 32 of the first frame plate 31. The suspension 38 is arranged inside the recess 32. The suspension 38 includes a coil spring 38a and receiving portions 38b arranged at both ends of the coil spring 38a. The coil spring 38a extends left and right through the recess 32 with the left and right direction as the axial direction. The coil spring 38a is sandwiched between the two rubber bushes 36b and 37b via the two receiving portions 38b.

As shown in FIG. 6, a mounting plate 39 is provided at the connecting portion between the first arm 41 and the first connecting rod 36 and at the connecting portion between the fifth arm 45 and the second connecting rod 37, respectively. The lock mechanism 50 described above is attached to the mounting plate 39.

10 is a schematic perspective view of the rear wheel mechanism 60 tilted to the left, and FIG. 11 is a schematic rear view of the rear wheel mechanism 60 tilted to the left. In FIG. 11, G indicates the ground, V indicates a perpendicular line to the ground, and θ indicates an angle formed by the first frame plate 31 and the perpendicular line V. As shown in FIGS. 10 and 11, when the vehicle body frame, that is, the first frame plate 31 is tilted to the left, the first arms 41 to the fourth arms 44 refer to the first frame plate 31 and the second frame plate 34. The fifth arm 45 to the eighth arm 48 rotate clockwise with respect to the first frame plate 31 and the third frame plate 35.

When the first frame plate 31 is tilted to the right, the first arms 41 to 4 rotate counterclockwise with respect to the first frame plate 31 and the second frame plate 34, and the fifth arm 45 The eighth arm 48 rotates counterclockwise with respect to the first frame plate 31 and the third frame plate 35. The first frame plate 31, the second frame plate 34, the third frame plate 35, and the first arms 41 to the eighth arms 48 are interlocked and rotate relatively smoothly according to the left-right inclination.

When only the right rear wheel rides on the convex portion on the road, only the first arm 41 to the fourth arm 44 rotate. When only the left rear wheel rides on the convex portion on the road, only the fifth arm 45 to the eighth arm 48 rotate. In these cases, the suspension 38 alleviates the impact force generated when riding on the convex portion. When the left and right rear wheels ride on the convex portions, the first arms 41 to the eighth arms 48 rotate. In this case, the suspension 38 alleviates the impact force generated when riding on the convex portion.

In the suspension device 30 and the electric motorcycle 1 according to the embodiment, the first arm 41 to the fourth arm 44 and the second frame plate 34 can be relatively rotated. Further, the fifth arm 45 to the eighth arm 48 and the third frame plate can be relatively rotated. The second frame plate 34 and the third frame plate 35 rotate independently of each other. Further, the first arm 41 and the second arm 42 are connected by the first connecting rod 36, and the fifth arm 45 and the sixth arm 46 are connected by the second connecting rod 37. There are no motors, no member connecting the 3rd arm 43 and 4th arm 44, and no member connecting the 7th arm 47 and 8th arm 48, and the two rear wheels have a simple configuration. The inclination of 14 can be controlled.

Further, by providing the suspension 38 between the first connecting rod 36 and the second connecting rod 37, when the second frame plate 34 or the third frame plate 35 moves upward or downward, the suspension 38 absorbs the impact force. do.

Further, by using the in-wheel motor 14a, it is not necessary to provide a motor, a differential gear, an axle, and the like, the arrangement space of the suspension device 30 can be increased, and the degree of freedom in designing the suspension device 30 can be improved. can.

The first arm 41 and the second arm 42 are connected by the first connecting rod 36 and form an H shape in a plan view. Further, the fifth arm 45 and the sixth arm 46 are connected by a second connecting rod 37 to form an H shape in a plan view. On the other hand, the fifth arm 45 to the eighth arm 48 are not connected by the connecting rod and form an I shape. Therefore, the rigidity of the upper H-shaped arm is higher than that of the lower I-shaped arm. Also, the lower I-shaped arm is more flexible than the upper H-shaped arm. Therefore, it is possible to stably secure the contact area of the tire and improve the followability of the tire to the road surface regardless of the change in the unevenness of the road surface. That is, it is possible to achieve both rigidity and followability to the road surface. Moreover, by making it an I type, it can be made lighter than the H type.

The embodiments disclosed this time should be considered to be exemplary in all respects and not restrictive. The technical features described in each example can be combined with each other and the scope of the invention is intended to include all modifications within the scope of the claims and the scope of the claims. Will be done.

1 Electric motorcycle 14 Rear wheel 14a In-wheel motor 30 Suspension device 31 1st frame plate 31a to 31d 1st through hole to 4th through hole 32 Recessed 34 2nd frame plate 35 3rd frame plate 36 1st connecting rod (1st) Connection part)
37 Second connecting rod (second connecting part)
36b, 37b rubber bush (support part)
38 Suspension 40a Bolt (Axis)
41-48 1st arm-8th arm

Claims (4)

The first frame plate, which has a U-shape when viewed from the side and has both ends protruding upward,
A second frame plate, which is arranged to face one surface of the first frame plate and supports the rear wheels of the electric motorcycle,
It is provided with a third frame plate which is arranged to face the other surface of the first frame plate and supports the rear wheels of the electric motorcycle.
A first through hole and a second through hole are formed at both ends of the first frame plate.
A third through hole and a fourth through hole are formed below the first through hole and the second through hole in the first frame plate.
In each of the first through hole to the fourth through hole, a pivot axis extending in a direction parallel to the first frame plate and intersecting in the vertical direction is arranged.
The first arm to the fourth arm, one end of which is rotatably connected to each of the pivots arranged in the first through hole to the fourth through hole and the other end of which is connected to the second frame plate.
The fifth arm to the eighth arm, one end of which is rotatably connected to each of the pivots arranged in the first through hole to the fourth through hole and the other end of which is connected to the third frame plate.
A first connecting portion that connects the first arm and the second arm,
A suspension device including a second connecting portion for connecting the fifth arm and the sixth arm. A suspension arranged in a recess of the first frame plate having a U-shaped side view and extending in the penetration direction from the first through hole to the fourth through hole,
The suspension device according to claim 1, further comprising support portions arranged in each of the first connecting portion and the second connecting portion and supporting both ends of the suspension. The suspension device according to claim 1 or 2, wherein an in-wheel motor is attached to the second frame plate and the third frame plate. Two rear wheels and
The first frame plate, which has a U-shape when viewed from the side and has both ends protruding upward,
A second frame plate that is arranged to face one surface of the first frame plate and supports one of the rear wheels, and a second frame plate.
It is provided with a third frame plate which is arranged to face the other surface of the first frame plate and supports the other rear wheel.
A first through hole and a second through hole are formed at both ends of the first frame plate.
A third through hole and a fourth through hole are formed below the first through hole and the second through hole in the first frame plate.
In each of the first through hole to the fourth through hole, a pivot axis extending in a direction parallel to the first frame plate and intersecting in the vertical direction is arranged.
The first arm to the fourth arm, one end of which is rotatably connected to each of the pivots arranged in the first through hole to the fourth through hole and the other end of which is connected to the second frame plate.
The fifth arm to the eighth arm, one end of which is rotatably connected to each of the pivots arranged in the first through hole to the fourth through hole and the other end of which is connected to the third frame plate.
A first connecting portion that connects the first arm and the second arm,
An electric motorcycle including a second connecting portion for connecting the fifth arm and the sixth arm.

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