WO2020008986A1

WO2020008986A1 - Vehicle

Info

Publication number: WO2020008986A1
Application number: PCT/JP2019/025541
Authority: WO
Inventors: 正伸鈴木
Original assignee: サーチウェア株式会社
Priority date: 2018-07-04
Filing date: 2019-06-27
Publication date: 2020-01-09
Also published as: JP2020006735A; JP6684417B2

Abstract

The objective of the present invention is to provide a vehicle with which it is possible for front wheels and a rear wheel to be steered smoothly by means of a difference between driving forces of a left and right pair of front wheels, and which is capable of being driven with a relatively small turning radius. A vehicle 1 is provided with a left and right pair of front wheels 3, one rear wheel 9, a front wheel support member 5 supporting the front wheels 3, a vehicle body frame 7, electric motors which impart a driving force individually to each front wheel 3, and a resistance force imparting device 47. The vehicle body frame 7 supports the rear wheel 9, and supports the front wheel support member 5 in such a way as to be capable of pivoting about an axis Lf. The rear wheel 9 is configured in such a way that a rolling direction thereof can change freely in all directions in the horizontal direction. A steering force causing the front wheel support member 5 to pivot about the axis Lf relative to the vehicle body frame 7 is generated by means of a difference between the driving forces of each front wheel 3. The resistance force imparting device 47 imparts a resistance force acting against the steering force. The resistance force imparting device 47 is controlled in such a way as to adjust the resistance force in accordance with an operating condition of the vehicle 1.

Description

vehicle

The present invention includes a pair of left and right front wheels and at least one rear wheel, and steers each front wheel by rotating a front wheel support member relative to a vehicle body by a difference in driving force between the pair of left and right front wheels. The present invention relates to a vehicle to be performed.

The conventional vehicle disclosed in Patent Document 1 is configured to steer each front wheel by rotating a front wheel support member around a steered shaft by a difference in driving force between a pair of left and right front wheels. The vehicle is steered by steering each front wheel.
Further, in the conventional vehicle disclosed in Patent Literature 2, the caster housing supporting the rear wheels rotates around the rear wheel steering shaft due to a yaw moment generated by a difference in driving force between the pair of left and right front wheels. It is configured to be steered. The urging force of the coil spring is always applied so as to oppose the rotation of the caster housing around the rear wheel turning shaft, and the urging force is configured to increase as the traveling speed increases.

Japanese Patent No. 5757511 Japanese Patent No. 6003712

However, in the conventional vehicle disclosed in Patent Literature 1, the rotation angle of the front wheel support member about the steered axis is limited to a certain range in order to avoid interference between the front wheel support member and the vehicle body. The turning radius when the vehicle turns can not be reduced too much.
Further, in the conventional vehicle disclosed in Patent Literature 2, the biasing force of the coil spring is always applied so as to oppose the rotation of the caster housing about the rear wheel turning shaft. Due to this difference, it was not possible to smoothly rotate the caster housing around the rear wheel turning shaft. Therefore, the responsiveness when turning the rear wheels by the yaw moment due to the difference in the driving force of each front wheel is poor.

The present invention has been made in order to solve such a problem, and a front wheel and a rear wheel can be smoothly steered by a difference in driving force between a pair of left and right front wheels, and a relatively small turning radius is provided. It is an object of the present invention to provide a vehicle that can be run on a vehicle.

In order to achieve this object, a vehicle according to the present invention includes a pair of left and right front wheels, at least one rear wheel, a front wheel support member that rotatably supports the front wheels, and a front wheel support member. A vehicle body rotatably supported about the axis of the vehicle and rotatably supporting the rear wheel; and a driving force applying means for individually applying a driving force to each of the front wheels. A steering force for rotating the front wheel support member about the first axis with respect to the vehicle body by a difference in drive force between the front wheels generated by individually applying drive force by drive force applying means. In a vehicle that steers each of the front wheels by rotating the front wheel support member about the first axis with respect to the vehicle body, in response to the steering force. A steering resistance applying hand that applies resistance And a control means for controlling the driving force applying means and the steering resistance applying means, wherein the rear wheel rolls in all directions in the horizontal direction or within a specified angle range in the horizontal direction. The direction is configured to be freely changeable, and the control unit is configured to control the turning resistance applying unit to adjust the resistance according to the driving situation of the vehicle. To do.

In the vehicle according to the second aspect of the present invention, in the vehicle according to the first aspect, the control unit may control the resistance when the vehicle is traveling at a lower speed than when the vehicle is traveling at a high speed. The invention is characterized in that the steering resistance applying means is controlled so as to increase the force.

According to a third aspect of the present invention, in the vehicle according to the first or second aspect, the control means is configured to temporarily increase the resistance when the front wheels are steered. In addition to controlling the steering resistance applying means, the driving force applying means is controlled such that the driving force applied to each of the front wheels is smaller on the front wheels on the outside in the steering direction than on the front wheels on the inside in the steering direction. Thereafter, the steering resistance applying means is controlled so that the resistance becomes smaller, and the driving force applied to each of the front wheels is set such that the driving force applied to each of the front wheels is smaller than that of the front wheels inside the steering direction. The driving force applying means is controlled so as to be larger.

A vehicle according to a fourth aspect of the present invention is the vehicle according to any one of the first to third aspects, wherein the rear wheel comprises a single rear wheel, and the rear wheel is rotatable. The vehicle further includes a rear wheel supporting member for supporting, the rear wheel supporting member is supported by the vehicle body so as to be rotatable around a second axis, and the first axis and the second axis are respectively The second axis is inclined so that the upper part is located forward of the lower part, and the intersection of the imaginary straight line extending downward and the traveling road surface when the vehicle is moving forward is the second axis. The rear wheel is disposed so as to be located forward of a rolling direction of the rear wheel from a ground contact point of the wheel with the traveling road surface.

A vehicle according to a fifth aspect of the present invention is the vehicle according to the fourth aspect, further comprising a rolling direction range changing unit capable of changing a range of a rolling direction to which the rear wheel can point, and the control unit The rolling direction range changing means is controlled by the following.

According to a sixth aspect of the present invention, in the vehicle according to the fifth aspect, the control means controls the rolling of the rear wheel when the vehicle runs at a higher speed than when the vehicle runs at a lower speed. The rolling direction range changing means is controlled so that the range of the direction is narrowed.

According to the first aspect of the present invention, the rear wheel is configured to be able to freely change the rolling direction, and the resistance against the steering force for turning the front wheel is adjusted according to the driving situation of the vehicle. It is configured to Therefore, by appropriately controlling the driving force applied to each front wheel and the resistance force against the steering force of the front wheels, it is possible to appropriately control the steering of the front wheels and the rear wheels according to the driving situation of the vehicle. it can. Further, since the rolling direction of the rear wheels can be freely changed, the responsiveness when the rear wheels are steered by the yaw moment due to the difference in the driving force of each front wheel is improved.

According to the second aspect of the present invention, when the vehicle travels at a low speed compared to when the vehicle travels at a high speed, the resistance against the turning force of the front wheels is controlled to be larger. During traveling, the rear wheels can be steered smoothly by the yaw moment due to the difference in driving force between the front wheels. For this reason, the vehicle can be turned with a relatively small turning radius, and small turns can be made even in narrow places.
On the other hand, when the vehicle travels at high speed, since the resistance against the steering force of the front wheels is controlled to be smaller than when traveling at low speed, the yaw moment due to the difference in the driving force between the front wheels is: The front wheel support member acts to rotate about the first axis with respect to the vehicle body. Therefore, turning by the rear wheels can be suppressed, and turning is mainly performed by the front wheels, so that high-speed turning performance can be ensured.

According to the third aspect of the invention, when the vehicle turns, the resistance force against the steering force of the front wheels and the driving force applied to each front wheel are appropriately controlled in two stages. I have. For this reason, the front wheel supporting member and the front wheel, which have been temporarily elastically deformed in the control of the first stage, and the restoring force for returning the front wheel to the original state, and the front wheel and the front wheel supporting member are controlled in the control of the second stage. It can be used as a force for relative rotation with respect to the vehicle body. Therefore, not only can the front wheels be steered quickly, but also there is no need to provide a special device for assisting the steering of the front wheels.

According to the fourth aspect of the present invention, the first shaft center, which is the center of rotation of the front wheel support member, is inclined such that the upper portion is located forward of the lower portion, so that the front wheel support member moves in the turning direction of the vehicle. When the vehicle turns, the vehicle body tilts inward in the turning direction, and accordingly, the second shaft center, which is the center of rotation of the rear wheel support member, also tilts. The second shaft center is inclined such that the upper portion is located forward of the lower portion, and the intersection of the extended virtual straight line and the traveling road surface is located forward of the contact point of the rear wheel in the rolling direction of the rear wheel. I have. For this reason, when the vehicle body leans, the vertical upward reaction force from the traveling road surface at the contact point of the rear wheel causes the rear wheel support member to rotate around the second axis through the rear wheel, thereby causing the rear wheel to rotate. It acts so that the front side in the rolling direction of the wheel is directed in the tilt direction of the vehicle body. As a result, the rear wheels are not directed excessively in the direction opposite to the inclination direction, so that the vehicle can turn stably.

According to the fifth aspect of the present invention, since the rolling direction range changing means capable of changing the range of the rolling direction to which the rear wheel can be directed is further provided, the rear wheel is set to a narrow angle range including the straight running direction at the center. By regulating the rolling direction, it is possible to prevent the rear wheel from undesirably largely turning around the second axis. In addition, since the rolling direction range changing means changes the range of the rolling direction of the rear wheel, the rolling direction of the rear wheel can be freely changed within the range. Providing the change means does not impair the responsiveness when the rear wheels are steered by the yaw moment due to the difference in driving force between the front wheels.

According to the invention described in claim 6, when the vehicle travels at a higher speed than when the vehicle travels at a lower speed, the range of the rolling direction of the rear wheels is controlled to be narrower. By restricting the rolling direction of the rear wheel to a narrow angle range including the rear wheel, the rear wheel may not move around the second shaft center due to the influence of disturbance such as crosswind and uneven road surface when the vehicle is running at high speed. It is possible to prevent the desired large rotation.
On the other hand, when traveling at low speeds, the range of the rolling direction of the rear wheels is controlled to be wider than when traveling at high speeds. Performance can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall view of a vehicle according to an embodiment of the present invention, which is viewed from a diagonally upper front. It is an external view which shows the state which looked at the same vehicle from the left side. It is an external view which shows the state which looked at the same vehicle from above. FIG. 2 is an external view showing the vehicle as viewed from the front. FIG. 2 is a block diagram illustrating a schematic configuration of a control device mounted on the vehicle and various devices related to the control device. FIG. 2 is a longitudinal sectional view showing a resistance applying device assembled to the vehicle in a cutaway manner. It is the figure which showed the state which fractured | ruptured the longitudinal direction middle part of the same resistance application apparatus, and was seen from diagonally upward.

FIG. 4 is a schematic diagram for explaining the behavior of the vehicle when turning at low speed. It is an external view which shows the state which looked at the same vehicle which is turning at low speed from above. It is an external view which shows the state which looked at the same vehicle turning at low speed from the front. It is a schematic diagram for explaining the behavior of the vehicle when turning at high speed. It is an external view which shows the state which looked at the same vehicle which is turning at high speed from the front. 6 is a graph showing a relationship between the magnitude of the resistance of the resistance applying device and the amount of steering on the front wheel side and the rear wheel side.

9 is a graph showing how the amounts of steering on the front wheel side and the rear wheel side change when the difference between the driving force applied to each front wheel and the resistance of the resistance applying device are changed. FIG. 2 is a longitudinal sectional view showing a rotation angle restricting device assembled to the vehicle in a cutaway manner. It is the figure which showed the state which removed the cover and looked at the rotation angle control apparatus from diagonally upward. It is a figure showing the 1st modification which changed control of vehicles concerning an embodiment of the present invention, and is a mimetic diagram for explaining behavior at the time of vehicles turning at high speed. It is a figure showing the 2nd modification which changed control of vehicles concerning an embodiment of the present invention, and is a mimetic diagram for explaining behavior at the time of vehicles turning at high speed.

FIG. 10 is an external view showing a state where a vehicle according to a second modification is turning at a high speed as viewed from above. FIG. 8 is a diagram showing a third modification in which the control of the vehicle according to the embodiment of the present invention is changed, wherein the difference between the driving force applied to each front wheel and the resistance applying device when the vehicle turns at high speed; FIG. 9 is a graph showing how the amount of steering on the front wheel side changes when the resistance of the vehicle changes with two-stage control. It is the longitudinal section which cut and showed the resistance application device concerning the 4th modification which has the composition different from the resistance application device of the vehicle concerning the embodiment of the present invention. FIG. 13 is an overall view of a vehicle according to a fifth modified example in which rear wheels of the vehicle according to the embodiment of the present invention and a mounting structure thereof are changed, as viewed obliquely from above and forward.

Hereinafter, an example of the vehicle according to the embodiment of the present invention will be described in detail with reference to FIGS. 1 to 4, FIG. 9, FIG. 10, and FIG. 12 indicate a vehicle according to an embodiment of the present invention. 1 to 3 and FIG. 9, the direction indicated by arrow F indicates the front of the vehicle 1. In the following description, the terms “left”, “right”, “up”, “down”, and “inside” and “outside” used to indicate directions and parts with respect to the vehicle 1 and its components are used when the components are assembled to the vehicle 1. In the state, it indicates the direction and position when the user gets on the vehicle 1 and sees it. A front portion of the vehicle 1 is provided with a pair of left and right

front wheels

3, 3. Each front wheel 3 is rotatably supported by a front wheel support member 5, and the front wheel support member 5 is swingably supported by a body frame 7. . A single rear wheel 9 is rotatably supported by a body frame 7 via a rear wheel support member 11 at a rear portion of the vehicle 1. The vehicle body frame 7 constitutes the “vehicle body” in the present invention.

The vehicle body frame 7 includes a tubular frame body 13 extending in the front-rear direction at the center in the left-right direction of the vehicle 1, a semicircular step 15 attached to an intermediate portion of the frame body 13 in the front-rear direction, A cylindrical shaft support member 17 attached to the front end, a handle post 19 attached to the frame body 13 near the rear of the shaft support member 17 and extending obliquely upward and rearward, and a rear end of the frame body 13 A cylindrical shaft support member 21 attached thereto. A central portion of the frame body 13 in the front-rear direction is bent downward, and a step 15 is attached to the bent portion. The frame main body 13 is disposed and connected to the center of the step 15 in the left-right direction at the front and rear ends thereof, which are concavely cut out. The frame body 13 extends forward and obliquely upward and rearward and obliquely upward from respective concavely cut portions at the front end and the rear end of the step 15. The intermediate portion in the front-rear direction of the frame main body 13 that is bent downwardly and convexly is positioned below the step 15.

The center portion of the front wheel support member 5 in the left-right direction is disposed within the shaft support member 17 and is steered by a front wheel steering shaft 23 (see FIG. 2) integrally connected to the shaft support member 17. The shaft 23 is supported by the shaft support member 17 so as to be rotatable around the axis Lf. The axis Lf is inclined such that its upper part is located forward of its lower part. The axis Lf constitutes the “first axis” in the present invention. Lower ends of a pair of left and right motor housings 27 are supported at both left and right ends of the front wheel support member 5 via a camber shaft 25 so as to be rotatable around an axis Lc of the camber shaft 25. The axis Lc is arranged so as to extend in the front-rear direction while being inclined so that the front portion is located lower than the rear portion. In each motor housing 27, an electric motor 29 (see FIG. 5) for individually applying a driving force to each front wheel 3 is provided. Each front wheel 3 has a so-called wheel-in-motor structure. The electric motor 29 constitutes “driving force applying means” according to the present invention. The rotating shaft of the electric motor 29 is connected to a hub (not shown) of each front wheel 3, and the rotating shaft of the electric motor 29 rotates the front wheel 3.

Due to a difference in driving force between the front wheels 3 generated by individually applying a driving force to each front wheel 3 by the electric motor 29, the front wheel supporting member 5 is rotated around the axis Lf with respect to the body frame 7. Steering force is generated. Each front wheel 3 is steered by rotating the front wheel support member 5 about the axis Lf with respect to the vehicle body frame 7. The driving force applied to each front wheel 3 when generating a driving force difference between the front wheels 3 includes a driving force for driving the front wheels 3 in the same direction as the traveling direction of the vehicle 1 and a driving force for the vehicle 1. The driving force for driving the front wheel 3 in the direction opposite to the traveling direction is included, and the driving force for driving the front wheel 3 in the opposite direction includes a regenerative braking force described later. The difference between the driving forces generated between the front wheels 3 is different from the case where different driving forces are applied to the front wheels 3 in the same direction. In some cases, the driving force is applied to the front wheels 3 respectively.

A pair of left and right rod-shaped camber link members 31 arranged to extend in the left-right direction is provided at a portion of the frame body 13 located between the portion to which the handle post 19 is attached and the portion to which the step 15 is attached. , 31 are rotatably connected via ball joints or rubber bushes, respectively, and the other end of each camber link member 31 is rotatably connected to the upper part of each motor housing 27 via a ball joint. Are linked.

On the other hand, in the rear wheel support member 11, a rear wheel steering shaft 11a (see FIG. 2) provided at an upper end portion thereof is inserted into the shaft support member 21, and the rear wheel steering shaft 11a is passed through the rear wheel steering shaft 11a. The shaft 11a is supported by the shaft support member 21 so as to be rotatable around the axis Lr. Thereby, the rear wheel 9 is configured to be rotatable around the axis Lr together with the rear wheel support member 11 in all directions in the horizontal direction, and the rolling direction is freely changeable in all directions in the horizontal direction. Have been. The axis Lr constitutes the “second axis” in the present invention.
The axis Lr is inclined such that its upper part is located forward of its lower part. As shown in FIG. 2, when the intersection point P of the virtual straight line S extending downward and the running road surface R of the vehicle 1 is in a state where the vehicle 1 is moving forward, the axis Lr is a rear wheel. The rear wheel 9 is disposed in front of the contact point Q with the traveling road surface R in the rolling direction of the rear wheel 9. Due to this arrangement, the rear wheels 9 can roll while following the progress of the vehicle 1 and pointing in an appropriate traveling direction.

Step 15, as shown in FIG. 2, includes a base plate 15a attached to the frame main body 13, and an upper surface plate 15b disposed above the base plate 15a. The occupant stands on the top plate 15b. A plurality of load sensors 33 are disposed between the base plate 15a and the upper plate 15b to detect a load applied to the upper plate 15b when an occupant stands. The number of the load sensors 33 to be provided may be any number as long as the load distribution on the front, rear, left and right applied to the upper surface plate 15b can be obtained, and at least three may be used. In the case of three, two are disposed on the base plate 15a on either the front side or the rear side at a position separated in the left-right direction, and one is disposed on the other side at the center position in the left-right direction.

ハンドル A handle 35 having an isosceles triangle shape is attached to the upper end of the handle post 19. The handle 35 includes a handle main body 35a and a grip 35b rotatable with respect to the handle main body 35a. The grip 35b is disposed at a position corresponding to the base of the isosceles triangle, and can be gripped by an occupant by hand. The grip 35b is configured to be rotatable around the axis of the grip 35b with the force of the occupant's hand, and returns to the neutral position by the spring force of a torsion spring (not shown) when the force of the hand is loosened. It is configured. A grip rotation sensor 37 (see FIG. 5) for detecting the rotation angle (including the rotation direction) of the grip 35b around the axis and the neutral position is provided in the handle body 35a.

A drive mode changeover switch 39 for switching the drive mode of the vehicle 1 is provided near the handle post 19 below the handle 35. The traveling mode changeover switch 39 allows the occupant to select and switch any one of "stop", "low speed traveling mode" and "high speed traveling mode". At an upper end portion inside the handle post 19, a handle turning power sensor 41 for detecting a turning force for turning the handle 35 around the axis of the handle post 19 with respect to the handle post 19, including a turning direction thereof, is disposed. Is established.

A front rotation sensor 45 (see FIG. 5) for detecting a rotation angle when the front wheel support member 5 relatively rotates with respect to the shaft support member 17 is provided in the shaft support member 17 of the body frame 7. Have been.
A resistance applying device 47 is disposed coaxially with the axis Lf of the front wheel steering shaft 23, and the resistance applying device 47 moves the front wheel supporting member 5 to the axis Lf by a difference in driving force between the front wheels 3. A resistance force is generated against the turning force for turning around. The resistance applying device 47 constitutes “resistance applying means” in the present invention. The magnitude of the resistance of the resistance applying device 47 is configured to be adjustable from substantially 0 to a predetermined magnitude according to the driving condition of the vehicle, and depending on the magnitude of the resistance, with respect to the shaft support member 17. It becomes difficult for the front wheel support member 5 to relatively rotate. Therefore, by appropriately controlling the driving force applied to each front wheel 3 and the resistance force against the turning force of the front wheels 3, the turning of the front wheels 3 and the rear wheels 9 is preferably performed according to the driving situation of the vehicle 1. Can be controlled. Further, since the rolling direction of the rear wheel 9 is freely changeable, the responsiveness when the rear wheel 9 is steered by the yaw moment due to the difference in the driving force of each front wheel 3 is improved.

On the other hand, a rear rotation sensor 49 for detecting a rotation angle when the rear wheel support member 11 relatively rotates with respect to the shaft support member 21 is provided in the shaft support member 21 at the rear end of the body frame 7. (See FIG. 5).
At the upper end of the shaft support member 21, a rotation angle regulating device 99 to be described later is connected. The turning angle restricting device 99 is disposed coaxially with the axis Lr of the rear wheel turning shaft 11a, and is capable of turning when the rear wheel supporting member 11 turns relative to the shaft supporting member 21. Is configured to be changeable. By changing the angle range in which the rear wheel support member 11 can rotate by the rotation angle regulating device 99, the range of the rolling direction in which the rear wheel 9 can be directed is also changed. Therefore, the rotation angle regulating device 99 constitutes "rolling direction range changing means" in the present invention.

The rear wheel support member 11 is provided with a rear wheel rotation sensor 53 (see FIG. 5) for detecting the rotation speed of the rear wheel 9. The running speed of the vehicle 1 is determined based on the value detected by the rear wheel rotation sensor 53. The running speed of the vehicle 1 is obtained by omitting the rear wheel rotation sensor 53, detecting the rotation speed of the rotating shaft of each electric motor 29, and calculating the average of the detected values. You may.
On the axle of the rear wheel 9, an electromagnetic brake 55 for braking the rear wheel 9 is provided. The electromagnetic brake 55 is configured so that the magnetic force continuously increases and decreases in accordance with the supplied electric power. As the supplied electric power increases, the magnetic force increases and the braking force decreases. When the electric power is cut off, a maximum braking force is applied by a spring force of a spring member in the electromagnetic brake 55. Note that, instead of the electromagnetic brake 55, a drum brake or a disc brake may be operated by driving an electric motor to generate a braking force.

As shown in FIGS. 6 and 7, the resistance applying device 47 includes an annular base member 61 rotatably supported by the front wheel steering shaft 23 via a bearing member 59, A cylinder 63 integrally joined to the upper surface, a partition wall 65 integrally joined to the upper end of the front wheel steering shaft 23, and a screw shaft arranged coaxially with the axis Lf of the front wheel steering shaft 23. 67, and an electric actuator 69 for moving the screw shaft 67 back and forth in the direction along the axis Lf. The front end of the front wheel support member 5 at the center in the left-right direction is attached to the outer peripheral surface of the base member 61. The cylinder 63 has an annular cylinder main body 63a having an axis coaxial with the axis Lf, an upper surface 63b and a lower surface 63c respectively closing an upper opening and a lower opening of the cylinder main body 63a in a liquid-tight manner. A movable partition 63d integrally formed with the cylinder body 63a so as to protrude from the inner peripheral surface of the cylinder body 63a toward the axis thereof. An oil chamber 71 for storing hydraulic oil is formed in the cylinder 63.

The partition wall 65 is formed integrally with the shaft portion 65a so as to protrude from the shaft portion 65a toward the inner peripheral surface of the cylinder body portion 63a. And a divided partition 65b. The opposing surface of the movable partition 63d opposing the outer peripheral surface of the shaft 65a is formed in an arc shape along the outer peripheral surface of the shaft 65a, and is configured to be slidable on the outer peripheral surface of the shaft 65a. As a result, the oil chamber 71 in the cylinder 63 is divided into two oil chambers by the movable partition 63d and the partition 65. A cylindrical shaft hole is formed in the shaft portion 65a of the partition wall 65 along the axis thereof, and the cylindrical lower end of the screw shaft 67 is inserted into the shaft hole. The outer peripheral surface of the cylindrical lower end is configured to be slidable on the inner peripheral surface of the shaft hole of the shaft portion 65a. The screw shaft 67 can move forward and backward with respect to the shaft portion 65a of the partition wall 65 in a direction along the axis of the screw shaft 67, but has a structure of a rotation stop so that relative rotation around the axis cannot be performed. Have been. A through hole 73 is formed in the shaft portion 65a so as to be orthogonal to the axis of the shaft hole of the shaft portion 65a, and an oil chamber 71 is defined by the movable partition 63d and the partition 65. The two oil chambers in the cylinder 63 communicate with each other only through the through hole 73.

The electric actuator 69 is integrally connected to a cylindrical case 69a, a rotation shaft 69b disposed coaxially with the axis Lf of the front wheel steering shaft 23 in the case 69a, and the rotation shaft 69b. A rotor 69c is provided around the rotary shaft 69b, and a stator 69d is provided around the rotor 69c and fixed to the inner peripheral surface of the case 69a. A through-hole is formed in the rotation shaft 69b along the axis thereof, and a female screw portion is formed on the inner peripheral surface of the through-hole over the entire area in the longitudinal direction. The screw shaft 67 is screwed into the female screw portion. When power is supplied to the electric actuator 69, the rotating shaft 69b rotates, and the screw shaft 67 advances and retreats in a direction along the axis Lf of the front wheel steering shaft 23. It is varied by the lower end of the shaft 67.

Each front wheel 3 vibrates due to the unevenness of the traveling road surface, and the vibration propagates, so that the front wheel support member 5 reciprocates around the axis Lf of the front wheel turning shaft 23 together with the base member 61 of the resistance applying device 47. However, due to the reciprocating rotation, the reciprocating rotation is attenuated by the flow resistance when the hydraulic oil in the resistance applying device 47 flows through the through hole 73. Therefore, the resistance applying device 47 also functions as a steering damper for applying a damping force to the steering system of the front wheels 3.

As shown in FIGS. 15 and 16, the rotation angle regulating device 99 includes a heart-shaped cam 101 attached to the upper end of the rear wheel steering shaft 11a, and a rod 103 which moves forward and backward by the cam surface of the cam 101. A pair of first spring members 107a and a second spring member 107b for applying a spring force to the rod 103 so as to hold the rod 103 at a neutral position; and a pair of annular first electromagnetic coils 109a for generating a magnetic force. And a second electromagnetic coil 109b, and a storage case 111 for storing these. The storage case 111 is connected to the upper end surface of the shaft support member 21. The storage case 111 has a cylindrical first storage portion 111a that stores the rod 103, each of the

spring members

107a and 107b, and each of the

electromagnetic coils

109a and 109b, and one end surface is integrally connected to the first storage portion 111a. And a second storage portion 111b for storing the cam 101.

The rod 103 has first and second small-

diameter portions

103a and 103b in the form of round bars having small outer diameters provided at both ends, respectively. A large-diameter cylindrical portion 103c having a diameter and a disk-shaped armature 103d provided in a longitudinally intermediate portion of the large-diameter portion 103c are provided. The

small diameter portions

103a and 103b, the large diameter portion 103c, and the armature 103d are formed integrally with each other. An intermediate portion in the longitudinal direction of the first small diameter portion 103a of the rod 103 is inserted into a through hole formed in the one end surface of the second storage portion 111b, and a cylindrical roller 112 is provided at a tip end of the first small diameter portion 103a. Is rotatably supported by a forked roller holding member 103e.

The first spring member 107a is interposed between the one end surface of the second storage portion 111b and one end surface of the large diameter portion 103c of the rod 103 so as to surround the first small diameter portion 103a of the rod 103. . The second spring member 107b is interposed between the disc-shaped side surface of the first storage portion 111a and the other end surface of the large diameter portion 103c of the rod 103 so as to surround the second small diameter portion 103b of the rod 103. . The first electromagnetic coil 109a is disposed so as to surround one end of the first small diameter portion 103a and one end of the large diameter portion 103c of the rod 103 and the first spring member 107a. The second electromagnetic coil 109b is disposed so as to surround the other ends of the second small diameter portion 103b and the large diameter portion 103c of the rod 103 and the second spring member 107b.

(4) When power is alternatively supplied to one of the pair of

electromagnetic coils

109a and 109b, a magnetic force acting on the armature 103d is generated. This magnetic force causes the rod 103 to move forward and backward against a spring force generated by compressing and compressing one of the pair of

spring members

107a and 107b. When the supply of power to the first electromagnetic coil 109a or the second electromagnetic coil 109b is stopped, the rod 103 is moved to the neutral position by one of the compressed spring force of the pair of

spring members

107a and 107b. To return.

The angle at which the rear wheel steering shaft 11a can rotate around its axis Lr is restricted to a predetermined range when the rod 103 is located at the neutral position, and the rod 103 moves most in the direction of the cam 101 when the rod 103 is at the neutral position. Is restricted to a narrow range including 0 ° in the center. These restrictions are performed when the roller 112 of the roller holding member 103e attached to the rod 103 comes into contact with the cam surface of the cam 101. When the rod 103 is moved to the position furthest away from the cam 101, the angle is 360 °, and the rotation of the rear wheel turning shaft 11a is not restricted. When the rod 103 is moved most in the direction of the cam 101, the rear wheel turning shaft 11a may be set to 0 ° so that the rear wheel turning shaft 11a cannot rotate at all. Further, the magnitude of electric power supplied to each of the

electromagnetic coils

109a and 109b may be appropriately adjusted so that the distance between the cam 101 and the rod 103 can be maintained at a desired distance.
The rotation angle restricting device 99 is configured to move the rod 103 back and forth by the magnetic force of the pair of

electromagnetic coils

109a and 109b. However, instead of such a configuration, the rod is driven by the rotation of the electric motor. An electric motor drive mechanism configured to move forward and backward may be used. The electric motor drive mechanism in this case constitutes "rotation angle regulating means" in the present invention.

On the other hand, a battery 75 is provided below the step 15, a control device 77 is provided in front of the battery 75, and an inertia sensor 79 is provided behind the battery 75. The control device 77 constitutes "control means" in the present invention. Power is supplied from the battery 75 to the electric motor 29, the electromagnetic brake 55, the electric actuator 69, the control device 77, and the

electromagnetic coils

109a and 109b. When the vehicle 1 is traveling, the inertial sensor 79 can detect each acceleration of the vehicle 1 in the front-back direction, the left-right direction, and the up-down direction, and each angular velocity of the vehicle 1 in the yaw direction, the roll direction, and the pitch direction. it can.
The control device 77 includes an input unit 81 to which various detection signals are input, an arithmetic processing unit 83 that calculates various target values based on the detection signals input via the input unit 81, and an arithmetic processing unit And a control unit 85 for controlling various control objects based on the target value calculated in 83.

Each interface in the input unit 81 includes the load sensor 33, the grip rotation sensor 37, the traveling mode changeover switch 39, the steering wheel rotation power sensor 41, the front rotation sensor 45, the rear rotation sensor 49, and the rear. The wheel rotation sensor 53 and the inertial sensor 79 are electrically connected via signal lines, respectively. The control unit 85 includes an electric motor control unit 91, a resistance control unit 93, an electromagnetic brake control unit 97, and a rotation angle control unit 100. These control units include the above-described electric motors 29, a resistance applying device. 47 and the electromagnetic brake 55 are each electrically connected via an output line.

Next, control by the control device 77 will be described.
First, when the travel mode changeover switch 39 is switched to the “stop” position, the supply of power from the battery 75 to the control target such as the electric motor 29 and the control device 77 is shut off. Accordingly, no driving force is generated in each of the electric motors 29, and the vehicle is stopped because the electromagnetic brake 55 is operating.
When the occupant switches the travel mode changeover switch 39, the changeover signal is input to the arithmetic processing unit 83 via the input unit 81. Is determined in the arithmetic processing unit 83 and is switched to "low speed traveling mode", the traveling speed is controlled by the control unit 85 so that it is only possible to travel at a preset reference speed V ₀ a rate of less than. On the other hand, when the arithmetic processing unit 83 determines that the mode has been switched to the “high-speed traveling mode”, the control unit 85 controls the traveling speed so that the traveling speed can be higher than the reference speed V ₀ . The reference speed V ₀ is, can be set as appropriate, may include, for example, 4km / h.

<In the case of low-speed running mode>
In the low-speed running mode, when the occupant stands in step 15, the detection values detected by the load sensors 33, the rear rotation sensor 49, and the rear wheel rotation sensor 53 are input to the arithmetic processing unit 83 via the input unit 81. Is input to Based on the input detection values, the arithmetic processing unit 83 determines a target speed when the vehicle 1 travels and a target turning amount when the traveling vehicle 1 turns. The turning amount includes, for example, a turning radius through which the center of the vehicle 1 passes when the vehicle 1 turns. The target turning amount refers to a target turning radius when the vehicle 1 turns. The obtained signal of the target speed and the target turning amount is transmitted to the electric motor control unit 91 of the control device 89, and each electric motor 29 is controlled by the electric motor control unit 91 based on the transmitted target speed and the target turning amount. You.

、 Specifically, each detection value detected by each load sensor 33 is input to the arithmetic processing unit 83 via the input unit 81, and the arithmetic processing unit 83 calculates the occupant load distribution to step 15. When the arithmetic processing unit 83 determines that the load distribution is shifted toward the front end side from the rear end side of step 15, the result is input to the electric motor control unit 91, and the electric motor control The electric motors 29 are controlled by the unit 91 so that the vehicle 1 moves forward. Conversely, when the arithmetic processing unit 83 determines that the load distribution is deviated toward the rear end side from the front end side in step 15, each electric motor 29 is controlled so that the vehicle 1 moves backward. You. In these cases, the driving force of each electric motor 29 is generated according to the ratio between the detection value according to the front end side load sensor 33 and the detection value according to the rear end side load sensor 33 in step 15. Controlled. Specifically, when the ratio of the detected values is 1, no driving force is generated in each of the electric motors 29. When the ratio of the detected values deviates from 1, the larger the amount of the deviation, the larger the driving force of each electric motor 29 is. Generate force.

Further, in addition to the deviation of the load distribution toward the front end side or the rear end side in step 15, if the load distribution further deviates toward the right end side from the left end side in step 15, the arithmetic processing unit 83. Is determined, the driving force of each electric motor 29 is distributed according to the ratio between the detected value according to the load sensor 33 on the left end side and the detected value according to the load sensor 33 on the right end side in step 15. Is controlled as follows. Specifically, when the ratio of the detected values is 1, the same driving force is generated in each electric motor 29. As a result, the vehicle 1 travels straight. On the other hand, when the ratio of the detected values deviates from 1, the larger the deviation amount, the larger the driving force is distributed to the electric motor 29 on the opposite side to the electric motor 29 on the side where the load distribution is deviated. Thereby, the vehicle 1 turns.
Then, when the vehicle 1 is traveling, each electric motor 29 is controlled by the electric motor control unit 91 so that the detection value of the rear wheel rotation sensor 53 matches the target speed. Further, when the vehicle 1 turns, each electric motor 29 is controlled by the electric motor control unit 91 such that the detection value of the rear rotation sensor 49 matches the target turning amount.

In the low-speed traveling mode, the electric actuator 69 of the resistance applying device 47 is controlled by the resistance control unit 93, and the through hole 73 is completely closed by the lower end of the screw shaft 67. As a result, the hydraulic oil in the oil chamber 71 can flow only through a small gap between the lower end of the screw shaft 67 and the through hole 73, so that the base member is The greatest resistance is applied when the cylinder 61 and the cylinder 63 relatively rotate. The control of the electric actuator 69 by the resistance control unit 93 is performed based on a control program previously obtained by an experiment so that the resistance changes stepwise or continuously.

As described above, in the low-speed running mode, the resistance against the turning force of the front wheels 3 is controlled so as to be larger than in the high-speed running mode described later, and the relative position of the front wheel support member 5 with respect to the front wheel turning shaft 23 is controlled. While the rotation is prevented, the rear wheel support member 11 is configured to be freely rotatable together with the rear wheel 9 around the axis Lr of the rear wheel turning shaft 11a. Therefore, when the vehicle 1 turns in the low-speed traveling mode, the following is performed. First, when shifting from the straight traveling state shown in FIG. 8A to the turning travel, the electric motor control unit is configured to generate a large driving force on the electric motor 29 of the front wheel 3 located outside the turning direction from inside the turning direction. Each electric motor 29 is controlled by 91.

As a result, a yaw moment in the turning direction is generated in the vehicle 1 due to a difference in driving force between the two electric motors 29, and as shown in FIGS. 8B and 9, the rear wheel 9 is caused by the yaw moment. Together with the rear wheel support member 11, it is relatively rotated around the axis Lr (clockwise) with respect to the vehicle body frame 7. As a result, since the rear wheels 9 can be steered smoothly, the vehicle 1 can be turned with a relatively small turning radius, and small turns can be made even in a narrow place. At this time, since the front wheel support member 5 hardly rotates around the axis Lf of the front wheel steering shaft 23, the vehicle 1 can turn without leaning in the left and right direction as shown in FIG. It is possible to improve the turning performance during low-speed running. The turning radius when the vehicle 1 travels fluctuates according to the difference in the driving force between the two electric motors 29. The larger the difference, the smaller the turning radius. You can also turn.

When each electric motor 29 is controlled by the electric motor control unit 91 so that the driving forces of the electric motors 29 become equal to each other during turning, a yaw moment in the direction opposite to the turning direction is applied to the vehicle 1. appear. Then, as shown in FIG. 8C, the rear wheel 9 is rotated together with the rear wheel supporting member 11 around the axis Lr (counterclockwise) relative to the body frame 7 by the yaw moment, as shown in FIG. The vehicle 1 returns from turning to straight running (see FIG. 8D).

In the low-speed traveling mode, the rotation angle control unit 100 controls the rotation angle control unit 100 so that power is not supplied from the battery 75 to any of the pair of

electromagnetic coils

109a and 109b in the rotation angle restriction device 99. Rod 103 is held at a neutral position by a pair of

spring members

107a and 107b. For this reason, in the low-speed traveling mode, the angle at which the rear wheel turning shaft 11a can rotate around the axis Lr is restricted to a predetermined range including the straight traveling direction at the center. As a result, in the low-speed running mode, when the vehicle 1 turns, the rear wheel turning shaft 11a can rotate with the rear wheel 9 around the axis Lr within a predetermined angle range including the straight traveling direction at the center. For this reason, the rear wheel 9 is freely steered in a predetermined angle range, so that the maneuverability of the vehicle 1 can be improved. In addition, since the rotation angle regulating device 99 changes the range of the rolling direction of the rear wheel 9, the rolling direction of the rear wheel 9 can be freely changed within the range. By providing the angle restricting device 99, the responsiveness when the rear wheel 9 is steered by the yaw moment due to the difference in the driving force of each front wheel 3 is not impaired.

When the electric motors 29 are controlled so that the vehicle 1 moves backward in the low-speed traveling mode, the rotation angle control unit 100 controls the second electromagnetic coil 109b so that electric power is supplied from the battery 75. . As a result, the rod 103 of the rotation angle regulating device 99 moves against the second spring member 107b and is held at the position farthest from the cam 101. As a result, the angle at which the rear wheel turning shaft 11a can rotate around its axis Lr is 360 °, so that the rear wheel turning shaft 11a moves with its rear wheel 9 around its axis Lr as the vehicle 1 moves backward. By turning, the rear wheel 9 changes its direction by 180 ° from the state shown in FIG. For this reason, the reverse movement of the vehicle 1 is performed smoothly.

<In the case of high-speed driving mode>
On the other hand, in the high-speed running mode, the grip rotation sensor 37, the steering wheel rotation power sensor 41, the front rotation sensor 45, the rear rotation sensor 49, the rear wheel rotation sensor 53, and the inertia sensor 79 are used instead of the load sensor 33 in step 15. The respective electric motors 29 are driven based on the respective detection values detected by. These detected values are input to the arithmetic processing unit 83 via the input unit 81, and the target speed when the vehicle 1 travels and the target turning amount when the running vehicle 1 turns are calculated by the arithmetic processing unit 83. Required by The obtained signal of the target speed and the target turning amount is transmitted to the electric motor control unit 91 of the control device 89, and each electric motor 29 is controlled by the electric motor control unit 91 based on the transmitted target speed and the target turning amount. You. Further, the current speed and the turning amount are obtained by the arithmetic processing unit 83 based on the detection values detected by the front rotation sensor 45, the rear rotation sensor 49, the rear wheel rotation sensor 53, and the inertia sensor 79, respectively. The electric motors 29 are controlled by the electric motor control unit 91 so that these values match the target speed and the target turning amount.

In the high-speed running mode, when the grip 35b is turned from the neutral position, the turning direction and the turning angle from the neutral position are detected by the grip turning sensor 37. The detected value is input to the arithmetic processing unit 83 via the input unit 81, and the control unit 85 controls each electric motor 29 based on the detected value. When the grip 35b is rotated in a rotation direction opposite to the rotation direction of the front wheel 3 when the vehicle 1 moves forward, the electric motor 29 is controlled in a direction in which the vehicle 1 moves forward. At this time, the electric motor 29 is controlled so that the traveling speed increases as the rotation angle of the grip 35b increases. When the grip 35b is turned in the opposite direction from the neutral position, the electric motor 29 is controlled such that the larger the turning angle, the larger the regenerative electric power is generated and the larger the regenerative braking force is applied to the vehicle 1. At this time, the electromagnetic brake 55 of the rear wheel 9 may be driven by the electromagnetic brake control unit 97 to supplement the regenerative braking of the front wheel 3 by the electric motor 29. Also, when the vehicle 1 is to be stopped urgently, the regenerative braking of the front wheels 3 by the electric motor 29 and the braking of the rear wheels 9 by the electromagnetic brake 55 may be simultaneously activated.

In the high-speed running mode, the electric actuator 69 of the resistance applying device 47 is automatically controlled by the resistance control unit 93, so that the lower end of the screw shaft 67 is retracted from the through hole 73 and the through hole 73 is completely opened. Is done. Thereby, the hydraulic oil in the oil chamber 71 can flow through the through-hole 73 without resistance, and the relative rotation of the base member 61 and the cylinder 63 with respect to the front wheel steering shaft 23 and the partition wall 65 is also allowed without resistance. You. As a result, the front wheel support member 5 attached to the base member 61 is also allowed to rotate relative to the front wheel steering shaft 23 without any resistance.

For this reason, when the vehicle 1 which is traveling straight turns into a turning run as shown in FIG. 11A, a large driving force is generated in the electric motor 29 of the front wheel 3 located outside the turning direction from the inside inside the turning direction. When the respective electric motors 29 are controlled by the electric motor control unit 91 in such a manner, the front wheel 3 and the front wheel supporting member 5 are easily rotated relative to the front wheel steering shaft 23 by the difference in the driving force between the two electric motors 29. (See FIG. 11B). At this time, since the front wheel supporting member 5 rotates around the axis Lf of the front wheel steering shaft 23 inclined forward, the vehicle body frame 7 is inclined inward in the turning direction, so that the turning property of the vehicle 1 during high-speed running is improved. Can be improved (see FIG. 12).

As described above, when the vehicle 1 runs in the high-speed running mode, the resistance against the steering force of the front wheels 3 is controlled to be smaller than when the vehicle 1 runs in the low-speed running mode. The yaw moment due to the difference in the driving force acts to rotate the front wheel support member 5 about the axis Lf with respect to the vehicle body frame 7. Therefore, turning by the rear wheels 9 is suppressed and turning is mainly performed by the front wheels 3, so that turning performance in the high-speed traveling mode can be ensured. In the high-speed running mode, the rotation angle control unit 100 controls the first electromagnetic coil 109a of the rotation angle regulating device 99 so that electric power is supplied from the battery 75. Accordingly, the rod 103 of the rotation angle regulating device 99 moves against the first spring member 107a and is held at the position closest to the cam 101. For this reason, the angle at which the rear wheel steering shaft 11a can rotate around its axis Lr is restricted to a narrow range including the straight running direction at the center, and the range of the rolling direction to which the rear wheel 9 can be directed is the low-speed running mode. It becomes narrower than when. As a result, it is possible to prevent the rear wheel 9 from undesirably largely turning around the axis Lr, and to reduce the influence of disturbance such as a cross wind and an uneven road surface received when the vehicle 1 is traveling at high speed. can do.

When the body frame 7 tilts inward in the turning direction, the axis Lr, which is the center of rotation of the rear wheel support member 11, also tilts. The axis Lr is inclined so that the upper part is located forward of the lower part, and the intersection P between the extended virtual straight line S and the traveling road surface R is located forward of the contact point Q of the rear wheel 9 in the rolling direction of the rear wheel 9. It is located in. For this reason, the upward reaction force in the vertical direction from the traveling road surface R at the contact point Q of the rear wheel 9 rotates the rear wheel support member 11 around the axis Lr via the rear wheel 9, and the rear wheel 9 Of the vehicle body 7 in the rolling direction. As a result, the rear wheel 9 does not excessively point in the direction opposite to the inclination direction, so that the vehicle 1 can stably turn.

On the other hand, the centrifugal force acting on the vehicle 1 when the vehicle 1 turns makes a balance with the frictional force between the front wheel 3 and the rear wheel 9 and the traveling road surface R. The friction force acts on the rear wheel 9 so that the front side in the rolling direction of the rear wheel 9 is directed outward in the turning direction. Therefore, when the vehicle 1 is turning, the pointing direction of the rear wheel 9 is determined by the vertical upward reaction force from the traveling road surface R acting on the ground contact point Q between the rear wheel 9 and the traveling road surface R, and the traveling direction. It is determined by the frictional force with the road surface R.
When the front side of the rear wheel 9 in the rolling direction is directed outward in the turning direction, the turning radius is reduced. , The course of the vehicle 1 can be changed smoothly.

Further, as described above, each camber shaft 25 is inclined such that the front portion thereof is located below the rear portion, and each motor housing 27 is connected to the frame main body 13 of the body frame 7 via each camber link member 31. Respectively. For this reason, when the front wheel 3 rotates relative to the front wheel steering shaft 23 together with the front wheel support member 5, the toe angle of each front wheel 3 becomes a toe-in state with the front wheel 3 positioned outside in the turning direction and inside the turning direction. Is in a toe-out state. This also contributes to improvement of the turning performance. At the same time, each front wheel 3 is inclined inward in the turning direction. That is, the front wheel 3 located inside the turning direction becomes a positive camber, and the front wheel 3 located outside the turning direction becomes a negative camber. As a result, it is possible to improve the grip force of each front wheel 3 on the traveling road surface during turning traveling.

When each electric motor 29 is controlled by the electric motor control unit 91 so that the driving force of each electric motor 29 is equal to each other while the vehicle 1 is turning, the front wheels 3 Is relatively rotated in the straight traveling direction together with the front wheel support member 5, and the vehicle 1 returns from the turning traveling to the straight traveling (see FIG. 11C). At this time, if the electromagnetic brake 55 of the rear wheel 9 is temporarily driven by the electromagnetic brake control unit 97, the front wheel support member 5 is rotated around the axis Lf of the front wheel steering shaft 23 so as to be directed straight. Since a moment is generated, the pointing direction of each front wheel 3 and front wheel supporting member 5 can be quickly returned to the straight traveling direction.

Here, the relationship between the magnitude of the resistance of the resistance applying device 47 and the amount of steering on the front wheel 3 side and the rear wheel 9 side will be described with reference to FIG. This figure shows the characteristics when the vehicle 1 turns while the difference in the driving force between the two electric motors 29 is maintained at a constant value, and the amount of steering on the front wheel 3 side and the rear wheel 9 side is represented on the vertical axis. , And the resistance applied by the resistance applying device 47 is plotted on the horizontal axis. The steering amount on the front wheel 3 side is a turning angle when the front wheel supporting member 5 turns around the axis Lf of the front wheel turning shaft 23, and corresponds to an absolute value of a detection value of the front turning sensor 45. . On the other hand, the turning amount on the rear wheel 9 side is a turning angle when the rear wheel support member 11 turns around the axis Lr of the rear wheel turning shaft 11a. It corresponds to the absolute value. In FIG. 13, the characteristic shown by the broken line is the steering amount on the front wheel 3 side, and the characteristic shown by the solid line is the steering amount on the rear wheel 9 side.
As can be seen from this figure, in a state where the difference in the driving force between the two electric motors 29 is kept at a constant value, the smaller the resistance of the resistance applying device 47, the larger the amount of steering on the front wheel 3 side and the rearward. The steering amount on the wheel 9 side is reduced. Then, as the resistance of the resistance applying device 47 increases, the steering amount on the front wheel 3 side decreases, and the steering amount on the rear wheel 9 side increases. The steering amount on the rear wheel 9 side is reversed and the steering amount on the rear wheel 9 side is larger than the steering amount on the front wheel 3 side.

Next, with reference to FIG. 14, a change in the amount of steering on the front wheel 3 side and the rear wheel 9 side when the difference in driving force between the two electric motors 29 and the resistance force of the resistance applying device 47 are changed. Will be explained. In this figure, the horizontal axis represents time, the vertical axis represents the difference in driving force between the two electric motors 29 in the graph (A), and the resistance of the resistance applying device 47 in the graph (B). In (C), the steering amounts of the front wheel 3 and the rear wheel 9 are respectively obtained. On the horizontal axis, Th time is a time zone in which the traveling mode changeover switch 39 is switched to the high speed traveling mode and the vehicle 1 is traveling at high speed, and T1 time is when the traveling mode changeover switch 39 is set to the low speed traveling mode. This is a time zone in which the vehicle 1 is running at a low speed after being switched, and during the Tm time, the running mode changeover switch 39 is switched to the high speed running mode and the vehicle 1 is driven at a middle speed between the high speed and the low speed. Is the time zone during which the vehicle is running.

グラフ In the graph (A) showing the difference in the driving force, the upper side around 0 is the case where the vehicle 1 turns leftward, and the lower side is the case where the vehicle 1 turns rightward. In the graph (C) showing the steered amount, the steered amount on the front wheel 3 side is a turning angle when the front wheel supporting member 5 turns around the axis Lf of the front wheel turning shaft 23, and is a front turning. This corresponds to the detection value of the sensor 45. On the other hand, the turning amount on the rear wheel 9 side is a turning angle when the rear wheel supporting member 11 turns around the axis Lr of the rear wheel turning shaft 11 a, and is a value detected by the rear turning sensor 49. Equivalent to. In the graph (C) showing the steering amount, the characteristic shown by the broken line is the steering amount on the front wheel 3 side, and the characteristic shown by the solid line is the steering amount on the rear wheel 9 side. The steering amount on the front wheel 3 side is a case where the upper side rotates counterclockwise around 0 and a case where the lower side rotates clockwise. On the other hand, the amount of steering on the rear wheel 9 side is a case where the upper side rotates clockwise around 0 and a case where the lower side rotates counterclockwise.

As can be seen from this figure, at time t1 in the high speed time zone, a difference in driving force is applied so that the vehicle 1 turns to the left, the resistance of the resistance applying device 47 is minimum, and the front wheels 3 The steering amount on the side shows a large value in the counterclockwise direction, and the steering amount on the rear wheel 9 side shows a small value in the clockwise direction. At the time t2 in the middle speed time zone, the difference in the driving force applied so that the vehicle 1 turns to the left is decreasing toward zero, and the resistance of the resistance applying device 47 is reduced. The force is about halfway between the minimum and maximum, the steering amount on the front wheel 3 side shows a constant value in the counterclockwise direction, and the steering amount on the rear wheel 9 side shows a constant value in the clockwise direction. At time t3 in the middle speed time zone, the difference in the driving force applied so that the vehicle 1 turns rightward is decreasing toward zero, and the resistance of the resistance applying device 47 is reduced. The force is about intermediate, and the steering amount on the front wheel 3 side shows a constant value in the clockwise direction, and the steering amount on the rear wheel 9 side shows a constant value in the counterclockwise direction. Further, at time t4 in the high-speed time zone, the difference in the driving force applied so that the vehicle 1 turns rightward is in the process of increasing, and the resistance of the resistance applying device 47 is maximum. The turning amount on the front wheel 3 side is 0, and the turning amount on the rear wheel 9 side shows a constant value in the clockwise direction and is decreasing toward 0.

Next, first to fifth modified examples as modified examples of the above-described embodiment will be described below with reference to FIGS. In the drawings referred to in the description of these modifications, the same or equivalent members, portions, directions, and the like as those described in the above embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. The points different from the embodiment will be mainly described in detail. Also in these modified examples, it is needless to say that the same operation and effect can be obtained for the same or equivalent configuration as that described in the above embodiment.

(First Modification)
In the embodiment described above, in the high-speed running mode, the vehicle 1 turns while the resistance applying device 47 is controlled such that the relative rotation of the front wheel support member 5 with respect to the front wheel steering shaft 23 is allowed without resistance. In this case, the steering of the vehicle 1 is mainly performed by each front wheel 3. However, the steering of the rear wheels 9 may be performed in addition to the steering by the front wheels 3. More specifically, the following control is performed.
First, when the vehicle 1 is traveling straight, the resistance control unit 93 controls the resistance application device 47 so that the resistance is reduced.
Next, when the vehicle 1 shifts from straight running to turning, each electric motor is controlled by the electric motor control unit 91 such that a large driving force is generated in the electric motor 29 of the front wheel 3 located outside the turning direction from inside the turning direction. 29 (see FIG. 17A). Then, a yaw moment in the turning direction is generated in the vehicle 1 due to a difference in driving force between the two electric motors 29, and the front wheel support member 5 rotates around the axis Lf of the front wheel turning shaft 23.

Next, at a predetermined timing until the current turning amount reaches the target turning amount obtained by the arithmetic processing unit 83, the resistance control unit 93 controls the resistance applying device 47 so that the largest resistance is generated. Control. As a result, a yaw moment in the turning direction is generated on the body frame 7 due to a difference in driving force between the two electric motors 29, and the yaw moment causes the rear wheel 9 and the rear wheel support member 11 to move the shaft center Lr with respect to the body frame 7. Acts so as to rotate relatively (clockwise) (see FIG. 17B). At this time, under the control of the turning angle control unit 100, the angle at which the rear wheel turning shaft 11a can turn around the axis Lr is restricted to a narrow range including the straight running direction at the center, but in that range, Wheel 9 can also be steered. As a result, not only the front wheels 3 but also the rear wheels 9 are steered, so that the turning performance of the vehicle 1 can be improved. Such control is suitable when traveling on a road where a plurality of curves having different turning directions are continuous.

When the turning vehicle 1 is returned to the straight traveling, as shown in FIG. 17C, the resistance by the resistance applying device 47 is controlled to be small, and the electric motors 29 are controlled. Each electric motor 29 is controlled so that the driving forces are equal to each other. Then, the front wheel 3 is relatively rotated with respect to the front wheel steering shaft 23 in the straight traveling direction together with the front wheel support member 5. At this time, if the electromagnetic brake 55 of the rear wheel 9 is temporarily driven by the electromagnetic brake control unit 97, the front wheel support member 5 is rotated around the axis Lf of the front wheel steering shaft 23 so as to be directed straight. Since a moment to be generated and a moment to rotate the rear wheel support member 11 around the axis Lr of the rear wheel steering shaft 11a are generated, the directivity directions of the front wheels 3 and the rear wheels 9 are quickly returned to the straight traveling directions. (See FIG. 17C). Then, the vehicle 1 returns from the turning traveling to the straight traveling (see FIG. 17D).

(Second Modification)
In a second modification, when the vehicle 1 turns in the high-speed traveling mode, the control of each electric motor 29 by the electric motor control unit 91 and the control of the resistance applying unit 47 by the resistance control unit 93 are performed as follows. This is performed by a method different from the above-described embodiment and the first modified example. More specifically, the following control is performed.
First, when the vehicle 1 is traveling straight, the resistance control unit 93 controls the resistance application device 47 so that the resistance is reduced.
Next, when the vehicle 1 shifts from straight running to turning, each electric motor is controlled by the electric motor control unit 91 such that a large driving force is generated in the electric motor 29 of the front wheel 3 located outside the turning direction from inside the turning direction. 29 (see FIG. 18A). Then, a yaw moment in the turning direction is generated in the vehicle 1 due to a difference in driving force between the two electric motors 29, and the front wheel support member 5 rotates around the axis Lf of the front wheel turning shaft 23.

Next, at a predetermined timing until the current turning amount reaches the target turning amount obtained by the arithmetic processing unit 83, the resistance control unit 93 controls the resistance applying device 47 so that the largest resistance is generated. Simultaneously with the control, each electric motor 29 is controlled by the electric motor control unit 91 so that a large driving force is generated in the electric motor 29 of the front wheel 3 located on the inner side in the turning direction from the outer side in the turning direction (FIG. 18B). reference). As a result, a yaw moment in the opposite direction to the turning direction is generated in the vehicle 1 due to a difference in driving force between the two electric motors 29, and the yaw moment causes the rear wheel 9 and the rear wheel support member 11 to move with respect to the body frame 7. Acting so as to rotate relatively around the axis Lr (counterclockwise in FIG. 18B). At this time, under the control of the turning angle control unit 100, the angle at which the rear wheel turning shaft 11a can turn around the axis Lr is restricted to a narrow range including the straight running direction at the center, but in that range, Wheel 9 can also be steered. As a result, the rolling direction of the front wheels 3 and the rolling direction of the rear wheels 9 approach a state of being parallel, so that the course of the vehicle 1 can be changed smoothly. FIG. 19 shows a state where the vehicle 1 is viewed from above at this time. Such control is suitable for changing lanes between a plurality of lanes.

When the turning vehicle 1 is returned to the straight traveling, as shown in FIG. 18C, the resistance by the resistance applying device 47 is controlled to be small, and the electric motors 29 are controlled. Each electric motor 29 is controlled so that the driving forces are equal to each other. Then, the front wheel 3 is relatively rotated with respect to the front wheel steering shaft 23 in the straight traveling direction together with the front wheel support member 5. At this time, if the electromagnetic brake 55 of the rear wheel 9 is temporarily driven by the electromagnetic brake control unit 97, the front wheel support member 5 is rotated around the axis Lf of the front wheel steering shaft 23 so as to be directed straight. Since a moment to be generated and a moment to rotate the rear wheel support member 11 around the axis Lr of the rear wheel steering shaft 11a are generated, the directivity directions of the front wheels 3 and the rear wheels 9 are quickly returned to the straight traveling directions. (See FIG. 18C). Then, the vehicle 1 returns from the turning traveling to the straight traveling (see FIG. 18D).

(Third Modification)
In a third modified example, when the vehicle 1 turns in the high-speed traveling mode, the control of each electric motor 29 by the electric motor control unit 91 and the control of the resistance applying unit 47 by the resistance control unit 93 are performed as follows. This is performed by a method different from that of the embodiment and the first and second modifications.
Specifically, the control is performed in two stages as shown by the solid lines in the graphs (A) to (C) of FIG. Note that, in these graphs, the characteristics shown by the broken lines show the characteristics when the two-stage control is not performed. In these graphs, the horizontal axis indicates time, the vertical axis indicates the difference between the driving forces between the two electric motors 29 in the graph (A), and the resistance by the resistance applying device 47 in the graph (B). In the graph (C), the steering amount on the front wheel 3 side is taken.

The graph (A) shows the case where the difference in the driving force is given so that the vehicle 1 runs in the turning direction on the upper side with respect to 0, and the driving force on the lower side moves the vehicle 1 in the counter-turning direction. This is the case where a difference is provided. The turning amount on the front wheel 3 side in the graph (C) is a turning angle when the front wheel supporting member 5 turns around the axis Lf of the front wheel turning shaft 23, and is a value detected by the front turning sensor 45. Equivalent to. In the graph (C), the angle of rotation in the turning direction increases as going upward.

First, as the control of the first stage, the resistance applying unit 47 is controlled by the resistance control unit 93 such that the resistance is temporarily increased when the vehicle starts turning in the high-speed traveling mode so as to be larger than that in the low-speed traveling mode (graph (See E in (A)). At this time, control is preferably performed so that the resistance is maximized. In addition to this control, the electric motor control unit 91 controls each electric motor so that the driving force applied to each front wheel 3 is smaller on the front wheel 3 located on the outside in the turning direction than on the front wheel 3 located on the inside in the turning direction. 29 (see F in graph (B)). That is, the difference in the driving force applied to each front wheel 3 acts to cause the vehicle 1 to travel temporarily in the anti-turn direction. As a result, the load on the traveling road surface of the front wheel 3 located outside the turning direction from the front wheel 3 located inside the target turning direction is temporarily increased, and the increased load causes the front wheel support member 5 to temporarily move. The front wheel 3 located on the outer side in the turning direction is also elastically deformed and depressed.

(4) Subsequently, as the control of the second stage, the resistance control unit 93 controls the resistance applying device 47 so as to reduce the resistance (see G in the graph (A)). Then, together with this control, the electric motor control unit 91 controls the driving force applied to each front wheel 3 so that the front wheels 3 located outside the turning direction are larger than the front wheels 3 located inside the target turning direction. (See H in graph (B)). Such control in the second stage is performed while the vehicle 1 is traveling at high speed without decreasing the traveling speed. As a result, the front wheel 3 is relatively rotated with the front wheel supporting member 5 with respect to the front wheel steering shaft 23 due to a difference in driving force between the two electric motors 29. At this time, the restoring force for returning the front wheel supporting member 5 and the front wheel 3 which have been temporarily elastically deformed in the control of the first stage to the original state is changed to the front wheel 3 and the front wheel 3 in the control of the second stage. The front wheel support member 5 can be used as a force for relatively rotating the front wheel steering shaft 23. Therefore, not only can the front wheel 3 be steered quickly, but also there is no need to provide a special device for assisting the steering of the front wheel 3.

This is indicated by the characteristic shown by the solid line when the above-described two-stage control is performed and the broken line when the two-stage control is not performed (in the case of the embodiment) in the graph (C) of FIG. It is clear from comparison with the characteristics shown.
When it is desired to return the vehicle 1 from turning to straight running, as a first step, the resistance of the resistance applying device 47 is temporarily controlled so as to increase, and the driving force applied to each front wheel 3 is controlled. After controlling each electric motor 29 so that each front wheel 3 is steered in the anti-return direction, control is performed as a second-stage control so that the resistance of the resistance applying device 47 is reduced. The difference between the driving forces applied to the front wheels 3 controls the electric motors 29 so that the front wheels 3 are steered in the return direction. Thereby, the vehicle 1 can be quickly returned from the turning traveling to the straight traveling.

(Fourth modification)
The resistance applying device 47 described in the above-described embodiment moves the screw shaft 67 by driving the electric actuator 69 to change the flow resistance when the hydraulic oil flows through the through-hole 73, and thereby the front wheel support member 5 The resistance force at the time of turning is adjusted. However, instead of this, the resistance applied when the front wheel supporting member 5 rotates may be adjusted by a resistance applying device 47 ′ as shown in FIG. The resistance applying device 47 ′ constitutes “turning resistance applying means” in the present invention. The resistance applying device 47 ′ includes a cylindrical shaft member 115 disposed coaxially with the axis Lf of the front wheel steering shaft 23 and integrally connected to an upper end of the front wheel steering shaft 23, and a bearing member 59. An annular base member 117 rotatably supported by the front wheel steering shaft 23 via a shaft, a bottomed cylindrical cylinder 119 integrally connected to an upper surface of the base member 117, and the cylinder 119 And an electromagnetic clutch device 121 disposed therein.

The electromagnetic clutch device 121 includes a tubular member 123 integrally bonded to an outer peripheral surface of a shaft member 115, and a plurality of first friction plates 125 arranged on the outer peripheral side of the tubular member 123, respectively. A second friction plate 127... And an annular armature 129 and an electromagnetic coil 131 disposed so as to sandwich the

friction plates

125 and 127, respectively, and a circle integrally bonded to the inner peripheral surface of the cylinder 119. And a tubular member 133. Each first friction plate 125 is attached to the tubular member 123 so that relative rotation about the axis Lf with respect to the tubular member 123 is restricted, and relative movement is allowed in a direction along the axis Lf. Have been. Each of the second friction plates 127 is attached to the tubular member 133 so that relative rotation with respect to the tubular member 133 around the axis Lf is restricted and relative movement is allowed in a direction along the axis Lf. Have been. The armature 129 is mounted on each of the

tubular members

123 and 133 such that relative rotation around the axis Lf and relative movement in a direction along the axis Lf are allowed. The electromagnetic coil 131 is connected to the tubular member 123.

In the low-speed traveling mode, the electromagnetic clutch device 121 of the resistance applying device 47 ′ is controlled by the resistance control unit 93, and the power of the battery 75 is supplied to the electromagnetic coil 131 to generate a magnetic force in the electromagnetic coil 131. The armature 129 is strongly attracted toward the electromagnetic coil 131. As a result, each first friction plate 125 and each second friction plate 127 are pressed against each other, and a large frictional force is generated therebetween, so that the base member 117 and the cylinder The largest resistance is applied when the motor 119 rotates relatively. The control of the electromagnetic clutch device 121 by the resistance force control unit 93 is performed based on a control program previously obtained by an experiment so that the frictional force changes stepwise or continuously.

The configuration for adjusting the frictional force between each first friction plate 125 and each second friction plate 127 is not limited to the configuration for changing the magnetic force between the armature 129 and the electromagnetic coil 131 as described above. . For example, a magnetic fluid in which fine particles of a magnetic material are dispersed in a liquid such as water or oil is interposed between each first friction plate 125 and each second friction plate 127, and generated by energizing an electromagnetic coil. By applying the generated magnetic field to the magnetic fluid, a resistance force may be generated between each first friction plate 125 and each second friction plate 127. According to such a configuration, by adjusting the strength of the magnetic field by increasing or decreasing the power supplied to the electromagnetic coil, the resistance of the magnetic fluid interposed between each first friction plate 125 and each second friction plate 127 can be improved. The force can be adjusted appropriately.

(Fifth Modification)
The rear wheel 9 described in the above embodiment has a structure in which the rear wheel supporting member 11 that supports the rear wheel 9 is supported by the body frame 7 so as to be rotatable in all horizontal directions. It was configured to be able to roll in the direction of. However, the rear wheel that can roll in all directions in the horizontal direction is not limited to the rear wheel 9 in the embodiment. For example, a rear wheel 9 'as shown in FIG. 22 may be employed. The rear wheel 9 'is constituted by an omni wheel, and is rotatably supported by a rear wheel support member 11' connected to the vehicle body frame 7. The rear wheel 9 'is provided with a pair of annular rolling elements in which a plurality of barrel-shaped rolling rollers 135 are arranged at equal angular intervals around the axle. Each of the rolling rollers 135 is individually rotatably supported by an annular retainer that constitutes a part of the rolling element, and thus can roll in a direction perpendicular to the axis of the rolling roller 135. In addition, the arrangement position of each rolling roller 135 in the circumferential direction of the rolling element is shifted between the pair of rolling elements, so that when the rolling element rolls, each rolling roller 135 is continuous without interruption. , So that it can smoothly roll. The rolling direction can be freely changed in all directions in the horizontal direction even by the rear wheel 9 'constituted by such an omni wheel.
Note that, in the case of the fifth modification, the rotation angle regulating device 99 that can change the range of the rolling direction in which the rear wheel 9 can be directed as in the above embodiment is not provided. The rear wheels 9 can roll in all horizontal directions without distinction between the low-speed running mode and the high-speed running mode.

The above-described embodiment and the first to fifth modified examples are examples for describing the present invention, and the present invention is not limited to the above-described embodiment and each modified example. The invention can be appropriately modified without departing from the gist or idea of the invention, which can be read from the entire book, and the vehicle after such a change is also included in the technical scope of the invention.

For example, in the above-described embodiment and each of the modifications, the load sensor 33, the grip rotation sensor 37, the steering wheel rotation power sensor 41, the front rotation sensor 45, the rear rotation sensor 49, the rear wheel rotation sensor 53, and the inertia sensor 79. The example in which the target speed and the target turning amount of the vehicle 1 and the current speed and the turning amount of the vehicle 1 are obtained by the arithmetic processing unit 83 in the control device 77 on the basis of the respective detected values is shown. However, instead of this, the map information stored in advance in a memory (not shown) in the control unit 85, the position information acquired by the global positioning system (GPS), the travel regulation information in the travel area, and the vehicle 1 A target speed and a target turn amount of the vehicle 1 and a current speed and a turn based on image information (an image of a traveling road and its surroundings, an image of a road sign, and the like) acquired by an on-board imaging device (not shown). The amount may be obtained by the arithmetic processing unit 83. The target turning amount at this time includes, for example, a trajectory through which the center of the vehicle 1 passes, in addition to a turning radius through which the center of the vehicle 1 passes when the vehicle 1 turns.

Further, the travel regulation information in the travel area may be obtained via a communication network such as the Internet, or the travel regulation information transmitted from the information transmission device installed in the travel area may be detected by the vehicle 1 The signal may be received wirelessly by a device (not shown). The arithmetic processing unit 83 automatically switches between the low-speed mode and the high-speed mode and avoids entry into the no-go area based on the driving regulation information received in this manner and the road sign image information acquired by the imaging device. You may make it perform it. The running area to be switched to the low-speed mode includes, for example, a sidewalk.

In the above embodiment, the shaft support member 17 and the shaft support member 21 are directly connected to the vehicle body frame 7, respectively. In the fifth modification, the rear wheel support member 11 'is directly connected to the vehicle body frame 7. An example of binding is shown. However, the present invention is not limited to this. The shaft support member 17, the shaft support member 21, and the rear wheel support member 11 'are connected to the vehicle body frame 7 via a shock absorber provided with an elastic member or a spring member made of a material such as rubber or resin. You may comprise so that it may support. In the case where the shaft support member 17 is configured to be supported on the vehicle body frame 7 via such a shock absorber, the two-step control in the above-described third modified example involves the control of the front wheel 3 and the front wheel support member 5. Not only elastic deformation but also bending of the elastic member or the spring member of the shock absorber is added. For this reason, the amount of restoring energy for returning the front wheel support member 5 and the front wheel 3 to the original state increases, and the front wheel 3 can be steered more quickly.

Further, in the above-described embodiment, in the case of the low-speed traveling mode, an example has been described in which the plurality of load sensors 33 are used to obtain the target speed and the target turning amount. However, instead of the load sensor 33, a plurality of simple switches that connect when a predetermined load or more is applied and shut off when no more load is applied may be provided in step 15. As another method, a joystick is attached to the handle post 19 or the handle 35, and the occupant operates the joystick to obtain a target speed and a target turning amount based on the operation amount and the operation direction. Is also good.
In the above-described embodiment and the fifth modification, the example in which only one rear wheel 9, 9 'is provided is shown. However, the present invention is not limited to this, and a pair of left and right rear wheels 9, 9' may be provided. .

DESCRIPTION OF SYMBOLS 1 Vehicle 3 Front wheel 5 Front wheel support member 7 Body frame (body)
9 Rear wheel 9 'Rear wheel 11 Rear wheel support member 29 Electric motor (drive force applying means)
47 Resistance applying device (turning resistance applying means)
47 'resistance applying device (turning resistance applying means)
77 Control device (control means)
99 Rotation angle regulating device (rolling direction range changing means)
Lf shaft center (first shaft center)
Lr shaft core (second shaft core)
R Road surface S Virtual straight line

Claims

A pair of left and right front wheels,
At least one rear wheel,
A front wheel supporting member that rotatably supports each of the front wheels,
A vehicle body that rotatably supports the front wheel support member about a first axis and rotatably supports the rear wheel;
Driving force applying means for individually applying a driving force to each of the front wheels,
The front wheel supporting member is turned around the first axis with respect to the vehicle body by a difference in driving force between the front wheels generated by individually applying the driving force to the front wheels by the driving force applying unit. To generate the steering force to move,
In a vehicle configured to steer each of the front wheels by rotating the front wheel support member around the first axis with respect to the vehicle body,
Turning resistance applying means for applying resistance against the turning force,
A control unit for controlling the driving force applying unit and the turning resistance applying unit,
The rear wheel is configured to be able to freely change the rolling direction in all directions in the horizontal direction or within a range of a specified angle in the horizontal direction,
The vehicle, wherein the control unit is configured to control the turning resistance applying unit to adjust the resistance according to a driving state of the vehicle.
The vehicle according to claim 1,
The control means is configured to control the turning resistance applying means such that the resistance increases when the vehicle is traveling at a lower speed than when the vehicle is traveling at a high speed. A vehicle characterized by being.
The vehicle according to claim 1 or 2,
The control means includes:
When the front wheels are steered, the steering resistance applying means is temporarily controlled so that the resistance is increased, and the driving force applied to the front wheels is turned from the front wheels on the inner side in the steering direction. After controlling the driving force applying means so that the front wheels on the outside in the rudder direction are smaller, subsequently,
The steering resistance applying means is controlled so that the resistance is reduced, and the driving force applied to each of the front wheels is greater on the front wheels on the outside in the steering direction than on the front wheels on the inside in the steering direction. A vehicle configured to control the driving force applying means.
The vehicle according to any one of claims 1 to 3,
The rear wheel includes a single rear wheel, and further includes a rear wheel support member that rotatably supports the rear wheel,
The rear wheel support member is supported by the vehicle body so as to be rotatable around a second axis,
The first axis and the second axis are inclined such that the upper portion is located forward of the lower portion,
The intersection of a virtual straight line extending downward and the traveling road surface when the vehicle is moving forward is defined by the second shaft center from the ground contact point of the rear wheel with the traveling road surface. The vehicle is arranged so as to be located forward in the rolling direction of the vehicle.
The vehicle according to claim 4,
Rolling direction range changing means capable of changing the range of the rolling direction in which the rear wheel can be directed is further provided,
A vehicle, wherein the control means controls the rolling direction range changing means.
The vehicle according to claim 5,
The control means is configured to control the rolling direction range changing means so that the range of the rolling direction of the rear wheel is smaller when the vehicle travels at a high speed than when the vehicle travels at a low speed. A vehicle characterized in that it has been made.