Tilting vehicle

Abstract

The invention provides a tilting vehicle which can maintain stable driving performance, can realize a stable tilting posture during turning, is simple and can reduce cost. A tilting vehicle is provided with: a plurality of wheel units provided to at least a front position and a rear position of a vehicle body and provided with a pair of wheels separated in a vehicle width direction; a tilting unit that is provided in the vicinity of one of the wheel units, and that is provided with a tilting mechanism that tilts the wheel unit and the vehicle body in the turning inward direction relative to the ground, and a tilting drive unit that drives the tilting mechanism; and passive suspensions which are provided to other wheel units among the wheel units and which generate roll rigidity when the vehicle body is inclined in the vehicle width direction with respect to the ground.

Description

Technical Field

[0001] The present disclosure relates to a tilting vehicle. Background Art

[0002] In the past, powered vehicles for a small number of people, such as small vehicles for one person, have been put into practical use as one of the simple moving units. In the case of such vehicles for a small number of people, miniaturization is achieved by shortening the length of the vehicle in the front-to-back direction and also by narrowing the vehicle width. On the other hand, if the vehicle width is narrowed, it becomes difficult to maintain the independence of the vehicle. For example, there is a situation where the vehicle posture becomes unstable due to the centrifugal force generated in the outer direction of the turn when the vehicle turns. Therefore, a tilting vehicle is proposed, which has a tilting mechanism that can tilt the vehicle body and the road surface (the wheels in contact with the ground) relative to the vehicle width direction (the inner direction of the turn) according to the driving state to balance the centrifugal force generated in the outer direction of the turn when the vehicle turns, thereby improving the stability of the vehicle posture.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2021-160610

[0004] In order to further popularize the above-mentioned leaning type vehicle, it is desired to provide a structure that can maintain stable running performance and realize a stable leaning posture when turning with a simple structure and easy cost reduction. Summary of the invention

[0005] Therefore, one of the problems to be solved by the embodiments of the present invention is to provide a simple and cost-reduced leaning type vehicle that can maintain stable running performance and achieve a stable leaning posture when turning.

[0006] A tilting vehicle as an example of the present disclosure comprises: a plurality of wheel units, which are arranged at at least the front and rear positions of the vehicle body and have a pair of wheels separated in the vehicle width direction; a tilting unit, which is arranged near a wheel unit of one of the wheel units and has a tilting mechanism and a tilting drive unit, wherein the tilting mechanism tilts the wheel unit and the vehicle body relative to the ground toward the inner side of the turn, and the tilting drive unit is used to drive the tilting mechanism; and a passive suspension, which is arranged on the other wheel units of the wheel unit and generates roll rigidity when the vehicle body is tilted relative to the ground in the vehicle width direction.

[0007] According to the above configuration, for example, a tilting unit is arranged at least at one of the front and rear wheel units of the vehicle body, and a passive suspension is arranged at the other wheel unit. Therefore, a tilting vehicle having a simple structure and a configuration that is easier to reduce cost can be provided, which performs roll suppression based on the roll rigidity of the passive suspension and tilt control based on the tilting unit in a good balance, thereby maintaining stable driving performance and achieving a more stable tilting posture when turning. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is an illustrative and schematic side view showing the structure of the tilting type vehicle according to the embodiment.

[0009] Figure 2 This is an illustrative and schematic image diagram showing a state in which the tilting type vehicle according to the embodiment is not tilted in the vehicle width direction when the tilting type vehicle is viewed from the rear side.

[0010] Figure 3 The diagram is an illustrative and schematic image diagram showing a state in which the leaning type vehicle according to the embodiment is tilted in the vehicle width direction (inner direction of a turn) when the leaning type vehicle is viewed from the rear side.

[0011] Figure 4 It is an illustrative and schematic perspective view showing the structure of a passive suspension provided at the front wheel of the leaning type vehicle according to the embodiment.

[0012] Figure 5 This is an illustrative and schematic image diagram showing a state in which the tilting type vehicle according to the embodiment is not tilted in the vehicle width direction when the tilting type vehicle is viewed from the front side.

[0013] Figure 6 The diagram is an illustrative and schematic image diagram showing a state in which the leaning type vehicle according to the embodiment is tilted in the vehicle width direction (inner direction of a turn) when the leaning type vehicle is viewed from the front.

[0014] Figure 7 This is an illustrative and schematic block diagram showing the configuration of a control device that performs tilt control in a tilting type vehicle according to an embodiment.

[0015] Description of Reference Numerals

[0016] 10…tilting vehicle, 12…vehicle body, 14…wheel, 16…wheel unit, 16R…rear wheel unit, 16F…front wheel unit, 24…control device, 24a…target tilt angle acquisition unit, 24b…actual tilt angle acquisition unit, 24c…deviation acquisition unit, 24d…motor torque determination unit, 24e…drive control unit, 38A…rear connecting device, 50…rear link mechanism, 52…tilt motor, 54…passive suspension, 56…upper arm, 58…lower arm, 64…shock absorber, 66…lever arm. DETAILED DESCRIPTION

[0017] Hereinafter, embodiments and modified examples of the present disclosure will be described based on the drawings. The configurations of the embodiments and modified examples described below, and the functions and effects of the configurations are merely examples, and are not limited to the following descriptions.

[0018] Figure 1 1 is an exemplary and schematic side view showing the structure of the tilting type vehicle 10 involved in the embodiment. The tilting type vehicle 10 of the present embodiment is provided with a tilting unit at least in one of the wheel units at the front and rear positions of the vehicle body, and a passive suspension capable of generating roll stiffness is provided in the other wheel unit. With this structure, compared with a vehicle having a tilting unit at the front and rear wheels, the cost of the tilting type vehicle 10 is reduced, and stable driving performance, particularly driving stability during cornering, can be maintained.

[0019] exist Figure 1 , the tilting vehicle 10 is shown to be arranged on the horizontal ground surface GL and not tilted. Figure 1 The front direction DF, rear direction DB, upper direction DU, lower direction DD, right direction DR, and left direction DL are shown. The front direction DF is the front direction (i.e., the forward direction) of the tilting vehicle 10, and the rear direction DB is the opposite direction of the front direction DF. The upper direction DU is the vertical upper direction, and the lower direction DD is the vertical lower direction (i.e., the opposite direction of the upper direction DU). The vertical lower direction is the direction of gravity. The right direction DR is the right direction observed from the tilting vehicle 10 traveling in the forward direction DF, and the left direction DL is the opposite direction of the right direction DR. The front direction DF, the rear direction DB, the right direction DR, and the left direction DL are all horizontal directions. The upper direction DU and the lower direction DD are, for example, perpendicular to the front direction DF.

[0020] The tilting vehicle 10 in this embodiment is, for example, a small vehicle for one person. The tilting vehicle 10 has a plurality of wheel units 16 (rear wheel unit 16R, front wheel unit 16F), which are provided at least in the front and rear positions of the vehicle body 12, and have a pair of wheels 14 separated in the vehicle width direction (right direction DR, left direction DL). That is, the tilting vehicle 10 in this embodiment is a four-wheel vehicle. In addition, Figure 1 This is a diagram seen from the right side of the tilting vehicle 10 , and for the convenience of explaining the structure, the right front and rear wheels 14 are omitted from illustration.

[0021] exist Figure 1 In the tilting vehicle 10 shown, for example, the rear wheel unit 16R is a unit for driving wheels. The driving wheel (rear wheel 14) can be driven and rotated by a power transmission mechanism such as a driving motor and a reduction mechanism, or can be driven and rotated by an internal wheel motor built into each wheel 14. On the other hand, the front wheel unit 16F is a non-driving wheel, and is a rotating wheel that can rotate in the vehicle width direction (i.e., the right direction DR and the left direction DL) of the tilting vehicle 10. The traveling direction of the rotating wheel is to be able to rotate to the right or left from the front direction DF. In addition, in other embodiments, the rear wheel unit 16R can also be set as a non-driving wheel, and the front wheel unit 16F can be set as a driving wheel that can rotate to the left and right directions. In addition, the tilting vehicle 10 can be provided with a wheel unit 16 having a pair of wheels 14 separated in the vehicle width direction at least in the front position and the rear position, for example, it can also have more than 6 wheels.

[0022] The vehicle body 12 has a main body 12a. The main body 12a includes a bottom 12b, a front wall 12c connected to the front direction DF side of the bottom 12b, a front portion 12d extending from the upper end of the front wall 12c toward the front direction DF, a rear wall 12e connected to the rear direction DB side of the bottom 12b, and a rear portion 12f extending from the upper end of the rear wall 12e toward the rear direction DB. The main body 12a has, for example, a metal frame and a panel fixed to the frame.

[0023] The vehicle body 12 also includes a seat 18 fixed to the bottom portion 12b, an accelerator pedal 20 and a brake pedal 22 arranged on the front side of the seat 18 in the direction DF, a control device 24 fixed to the bottom portion 12b, and a handle 26 installed on the front portion 12d. In addition, although not shown in the figure, other components (for example, a roof, a headlight, etc.) can be fixed to the main body 12a.

[0024] The seat 18 includes a seat surface portion 18 a and a backrest portion 18 b so that the driver can perform depression adjustment operations of the accelerator pedal 20 and the brake pedal 22 and steering operations of the handle 26 in a sitting posture.

[0025] The accelerator pedal 20 adjusts the output state of the drive motor that rotates the drive wheels (rear wheels 14) by adjusting the depression amount of the driver. The brake pedal 22 adjusts the braking state of the mechanical brake provided on the wheels 14 by adjusting the depression amount of the driver.

[0026] The handle 26 is a component that can be rotated to the right and left directions. The rotation angle (also called the input angle) of the handle 26 relative to a specified rotation position indicating straight travel (also called the straight travel rotation position) is an example of turning target information indicating the target direction of the turn and the target degree of the turn. In the present embodiment, "input angle = zero" indicates straight travel, "input angle > zero" indicates a right turn, and "input angle < zero" indicates a left turn. The size of the input angle (i.e., the absolute value) indicates the target degree of the turn. The driver can input the turning target information by operating the handle 26. In addition, the connection between the handle 26 and the steering mechanism that steers the wheel 14 on the front wheel side can be achieved by either a mechanical steering mechanism with a mechanical connection or an electrically connected wire-controlled steering.

[0027] A direction sensor 28 is fixed to a part of the vehicle body 12, for example, the rear wall portion 12e. The direction sensor 28 is a sensor for measuring the roll angle and yaw angular velocity of the vehicle body 12. In addition, the direction sensor 28 includes an acceleration sensor 30, a gyro sensor 32, and a control unit 34. The acceleration sensor 30 is a sensor for detecting acceleration in an arbitrary direction, for example, a three-axis acceleration sensor. In addition, the direction of the acceleration detected by the acceleration sensor 30 is referred to as a detection direction. When the tilting vehicle 10 is stopped, the detection direction is the same as the vertical downward direction DD. The gyro sensor 32 is a sensor for detecting an angular velocity centered on a rotation axis in an arbitrary direction, for example, a three-axis angular velocity sensor. The control unit 34 determines the roll angle and yaw angular velocity using a signal from the acceleration sensor 30, a signal from the gyro sensor 32, and a signal from a velocity sensor 36, for example, arranged in the front wheel unit 16F. The control unit 34 is, for example, a data processing device including a computer. These sensors constitute an inertial measurement unit (IMU) and can acquire the actual tilt state (actual tilt angle) of the tilting type vehicle 10 during travel.

[0028] First, the rear wheel unit 16R mounted on the tilting type vehicle 10 will be described.

[0029] like Figure 1 As shown, in the tilting vehicle 10, the rear wheel unit 16R disposed on the rear side of the rear wall portion 12e of the vehicle body 12 in the DB direction includes a rear connecting device 38A that connects the wheel 14 on the rear wheel side and the vehicle body 12. Figure 1The tilting vehicle 10 shown in the figure shows an example in which the wheel 14 on the rear wheel side is rotationally driven by a power transmission mechanism such as a driving motor 40 and a speed reduction mechanism 42. In addition, the rear wheel unit 16R includes a battery 44 for supplying power to the driving motor 40, the tilting motor of the tilting unit described later (for driving the tilting driving part of the tilting mechanism), and various devices mounted on the tilting vehicle 10. Therefore, for the weight distribution of the vehicle body 12 of the tilting vehicle 10 of this embodiment, the rear wheel unit 16R side with the tilting unit is distributed more than the front wheel unit 16F side (the suspension mounting side described later) without the tilting unit. As a result, the tilting motor torque generated by the tilting unit can be transmitted to the road surface (ground GL) more, and the posture control performance based on the tilting unit can be improved. The driving motor 40 is rotationally controlled according to the amount of depression of the accelerator pedal 20, and the rear wheel 14 is rotationally driven via the speed reduction mechanism 42. The power transmission mechanism using the driving motor 40, the speed reduction mechanism 42, the battery 44, etc. can use a known structure, and a detailed description is omitted.

[0030] The rear wheel unit 16R and the vehicle body 12 are connected by a rear connecting rod 46A. With respect to the rear connecting rod 46A, the end 46Aa on the vehicle body 12 side is rotatably connected to the vehicle body 12, and the end 46Ab on the rear wheel unit 16R side is fixed to the rear wheel unit 16R. In addition, a rear spring component 48 that functions as a suspension is sandwiched between the middle portion of the rear connecting rod 46A and the vehicle body 12. As a result, the rear wheel unit 16R (the wheel 14 serving as the rear wheel) and the vehicle body 12 can move (rotate) relative to each other in the up-and-down direction. For example, when driving on a bumpy ground GL, the main up-and-down displacement of the rear wheel unit 16R can be reduced and the up-and-down vibration can be transmitted to the vehicle body 12 side. In addition, in Figure 1 In the case of the structure of the rear spring member 48, there is only one rear spring member 48 in the substantially central portion in the vehicle width direction, and it does not have roll rigidity. Therefore, the rear wheel unit 16R of the tilting type vehicle 10 of the present embodiment does not have a structure that generates roll rigidity by a spring element. In addition, the front wheel unit 16F (the front connecting mechanism 38B described later) is connected to the vehicle body 12 through the front connecting rod 46B. The end 46Ba of the front connecting rod 46B on the vehicle body 12 side is fixed to the vehicle body 12, and the end 46Bb on the front wheel unit 16F side is fixed to the front wheel unit 16F.

[0031] Figure 2 1 is an illustrative and schematic image diagram showing a state in which the tilting vehicle 10 is not tilted in the vehicle width direction when the tilting vehicle 10 is viewed from the rear side. Figure 3 1 is an illustrative and schematic image diagram showing a state in which the tilting vehicle 10 is tilted in the vehicle width direction (inner direction of the turn) when the tilting vehicle 10 is viewed from the rear side. Figure 2 , Figure 3 In order to facilitate understanding of the behavior of the tilting type vehicle 10 , illustration of the power transmission mechanism such as the drive motor 40 and the speed reduction mechanism 42 in the rear coupling device 38A is omitted.

[0032] As described above, the rear connecting device 38A connects the two wheels 14 (rear wheels) and the vehicle body 12. In addition, the rear connecting device 38A includes a tilting unit. The tilting unit includes a rear link mechanism 50 that functions as a tilting mechanism (a mechanism that tilts the tilting vehicle 10 toward the inner side of the turn) and a tilt motor 52 installed in the rear link mechanism 50 that functions as a tilting drive unit.

[0033] The rear link mechanism 50 is a so-called parallel link, and has a function of tilting the rear wheel unit 16R (wheel unit) and the vehicle body 12 relative to the ground toward the inner side of the turn. The rear link mechanism 50 includes three longitudinal link members 50a, 50b, and 50c arranged in sequence toward the right direction DR, and two transverse link members 50d and 50e arranged in sequence toward the downward direction DD. Figure 2 As shown, when the tilting vehicle 10 is standing upright without tilting on the horizontal ground GL (i.e., the ground GL perpendicular to the vertical upper direction DU) (posture SR1), the longitudinal link members 50a, 50b, 50c are parallel to the vertical direction, and the transverse link members 50d, 50e are parallel to the horizontal direction. The two longitudinal link members 50a, 50c and the two transverse link members 50d, 50e form a parallelogram link mechanism. The longitudinal link member 50b connects the central parts of the two transverse link members 50d, 50e. The longitudinal link members 50a, 50b, 50c and the transverse link members 50d, 50e are formed of metal, for example.

[0034] The rear link mechanism 50 has a bearing that rotatably connects a plurality of link members. For example, the bearing 54a rotatably connects the longitudinal link member 50b and the transverse link member 50e. In addition, the bearing 54b rotatably connects the longitudinal link member 50a and the transverse link member 50e. The bearing 54c rotatably connects the longitudinal link member 50c and the transverse link member 50e. The other link members are also rotatably connected to each other through bearings. The rotation axis of the bearings 54a, 54b, etc. that connect the link members extends from the rear direction DB side to the front direction DF side (in this embodiment, the rotation axis is parallel to the front direction DF). The two link members connected to each other can rotate relative to each other within a predetermined angle range (for example, a range less than 180 degrees) with the rotation axis as the center. Through this structure, it is possible to realize a structure in which the rear link mechanism 50 causes the rear wheel unit 16R and the vehicle body 12 to tilt relative to the ground GL toward the inner side of the turn (the vehicle width direction). For example, in the case where the leaning vehicle 10 turns, Figure 3As shown, the tilting vehicle 10 is tilted toward the inner side of the turn (right direction DR) in order to resist the centrifugal force generated in the outer side of the turn (left direction DL). When the vehicle body is tilted toward the inner side of the turn in order to resist the centrifugal force, the turning of the tilting vehicle 10 is stable, but if the centrifugal force becomes larger, the vehicle body 12 shakes in the outer side of the turn, and the stability is reduced. Therefore, in order to continue the good turning, it is necessary to take a posture that intentionally tilts the tilting vehicle 10 toward the inner side of the turn. Therefore, the rear link mechanism 50 intentionally tilts the tilting vehicle 10 toward the inner side of the turn through the tilt motor 52, so as to improve the posture stability of the tilting vehicle 10 in the turn.

[0035] The tilt motor 52 is an example of a driving device configured to drive the rear link mechanism 50, such as an electric motor. The tilt motor 52 is connected to the longitudinal link member 50b and the upper transverse link member 50d, for example. The tilt motor 52 rotates the transverse link member 50d relative to the longitudinal link member 50b. As a result, the wheel 14 (vehicle body 12) tilts toward the inner side of the turn (i.e., the right or left direction of the vehicle width direction). Such tilting motion is also called roll motion. In addition, the tilt motor 52 and the longitudinal link member 50b can also be connected via gears. In addition, the tilt motor 52 and the transverse link member 50d can also be connected via gears. Hereinafter, the torque generated by the tilt motor 52 will also be referred to as the tilt motor torque. The tilt motor torque causes the vehicle body 12 to tilt. That is, it is possible to achieve control of tilting the rear wheel unit 16R and the vehicle body 12 relative to the ground GL toward the inner side of the turn. In addition, in other embodiments, the tilt motor can also be fixed to the rear wheel unit 16R, and the output side (rotation axis side) of the tilt motor can be connected to the vehicle body 12. In this case, by relatively tilting the rear wheel unit 16R and the vehicle body 12, the rear wheel unit 16R and the vehicle body 12 can also be tilted relatively toward the inner side of the turn with respect to the ground surface GL.

[0036] Figure 2 The posture SR1 shown shows a state where the tilting vehicle 10 is standing upright. Figure 3 The posture SR2 shown shows a state where the tilting vehicle 10 is tilted relative to the horizontal ground GL. As shown in the posture SR1, when the horizontal link member 50d is perpendicular to the vertical link member 50b, the wheel 14 as the rear wheel stands upright relative to the horizontal ground GL. Moreover, the tilting vehicle 10 including the vehicle body 12 stands upright relative to the ground GL as a whole. Figure 2 The vehicle body upper direction DVU is the upper direction of the vehicle body 12. When the tilting vehicle 10 is not tilted, the vehicle body upper direction DVU is the same as the upper direction DU. In the present embodiment, the upper direction predetermined for the vehicle body 12 is used as the vehicle body upper direction DVU.

[0037] When the tilting vehicle 10 in the posture SR1 is traveling straight, if the ground surface GL has unevenness, the wheel 14 is displaced in the vertical direction by the vertical parallel movement of the rear link mechanism 50, and the rear wheel unit 16R (rear link mechanism 50) can be relatively moved (rotated) in the vertical direction with respect to the vehicle body 12 by the cooperation between the rear connecting rod 46A and the rear spring member 48. As a result, when the tilting vehicle 10 travels on the ground surface GL with unevenness, for example, the vertical vibration transmitted to the vehicle body 12 is reduced, which can contribute to improving the driving stability.

[0038] On the other hand, Figure 3 As shown in the posture SR2, in the rear view, the longitudinal link component 50b rotates clockwise relative to the transverse link component 50d, so that the wheel 14R as the right rear wheel moves to the upper direction DVU side of the vehicle body, and the wheel 14L as the left rear wheel moves to the opposite side relative to the vehicle body 12. Therefore, in a state where the wheels 14R and 14L as the rear wheels are in contact with the ground GL, the wheels 14L and 14R, and thus the vehicle body 12, are tilted to the right direction DR side relative to the ground GL. For example, when the tilting vehicle 10 turns right, the vehicle body 12 can be tilted to the inner side of the turn (right direction DR) so as to balance the centrifugal force generated in the outer side of the turn. In this case, by controlling the tilt motor 52, the tilt amount of the vehicle body 12 to the inner side of the turn can be appropriately adjusted. In addition, the longitudinal link component 50b rotates counterclockwise relative to the transverse link component 50d, so that the vehicle body 12 tilts to the left direction DL side. In other words, the vehicle body 12 can be tilted so as to achieve balance with the centrifugal force even when turning left.

[0039] exist Figure 3 In the posture SR2 shown, the vehicle body upper direction DVU is tilted toward the right direction DR relative to the upper direction DU. Hereinafter, the angle between the upper direction DU and the vehicle body upper direction DVU when the tilting vehicle 10 is viewed toward the front direction DF is referred to as the roll angle Ar, or the tilt angle Ar. Here, "Ar>0" indicates a tilt toward the right direction DR, and "Ar<0" indicates a tilt toward the left direction DL. The roll angle Ar of the vehicle body 12 can be referred to as the roll angle Ar of the tilting vehicle 10 having the vehicle body 12.

[0040] Showing posture SR2 Figure 3, the rear control angle ACr of the rear link mechanism 50 is shown. The rear control angle ACr represents the angle of the direction of the longitudinal link member 50b relative to the direction of the transverse link member 50d. In the rear view showing the posture SR2, "ACr=0" means that the longitudinal link member 50b is perpendicular to the transverse link member 50d. "ACr>0" represents the state in which the longitudinal link member 50b is rotated clockwise relative to the transverse link member 50d from the state of "ACr=0". Although omitted in the figure, "ACr<0" represents the state in which the longitudinal link member 50b is rotated counterclockwise relative to the transverse link member 50d from the state of "ACr=0". As shown in the figure, when the tilting vehicle 10 is located on a horizontal ground GL (i.e., a ground GL perpendicular to the vertical upper direction DU), the rear control angle ACr is approximately the same as the roll angle Ar.

[0041] Although described later, the front wheel unit 16F is provided with a passive suspension 54, and the greater the inclination (roll) of the vehicle body 12, the greater the roll rigidity is generated, and at the same time, a link mechanism is provided that can tilt the wheel 14 as the front wheel in the vehicle width direction. Therefore, the vehicle body 12 can also be tilted in the vehicle width direction relative to the ground on the front wheel side. In other words, the tilting vehicle 10 can adjust the posture of the vehicle body 12 relative to the vehicle width direction according to the driving state and the road surface state, and change it to a posture suitable for driving.

[0042] As described above, the rear link mechanism 50 on the rear wheel side tilts (rolls) the vehicle body 12 toward the inner side of the turn so as to maintain balance with the centrifugal force generated during the turn by the tilt motor 52. In this case, the front wheel 14 can also tilt in the same manner due to the tilt.

[0043] The rear link mechanism 50 and the link mechanism on the front wheel side described later are examples of a tilting device configured to tilt the vehicle body 12 in the vehicle width direction of the tilting vehicle 10 (sometimes referred to as a front tilting device or a rear tilting device). The tilt motor 52 is an example of a driving device configured to generate a driving force (i.e., a tilt motor torque) for driving the rear tilting device (sometimes referred to as a rear drive device). The driving force of the rear drive device is a force that tilts the vehicle body 12 in the direction of the inner side of the turn relative to the wheels 14 that are a pair of rear wheels.

[0044] In addition, the rear wheel unit 16R may also include a locking mechanism (not shown) for stopping the operation of the rear link mechanism 50. By operating the locking mechanism, the rear control angle ACr can be fixed. As a result, for example, when the tilting vehicle 10 is parked, the rear control angle ACr can be fixed to 0, and the parking posture can be stabilized.

[0045] Next, the front wheel unit 16F will be described. Figure 438B is an illustrative and schematic perspective view showing the structure of a passive suspension 54 which is a link mechanism (also referred to as a front link mechanism 38B) on the front wheel side included in the front wheel unit 16F and is provided on the front wheel side of the leaning vehicle 10. Figure 4 This is for explaining the basic operation of the passive suspension 54 , and illustration of components not involved in the explanation is omitted.

[0046] The passive suspension 54 (front link mechanism 38B) is, for example, a well-known double wishbone suspension, and is composed of an upper arm 56, a lower arm 58, a ball joint 60 (only one side is shown), a hub knuckle 62 (only one side is shown), a shock absorber 64, etc.

[0047] As described above, the basic structure of the double wishbone passive suspension 54 is a well-known structure and detailed description is omitted, but a pair of upper arms 56 and lower arms 58 separated in the vehicle height direction are respectively provided for the left and right wheels 14. The ends of the upper arm 56 and the lower arm 58 on the side away from the wheel 14 are rotatably connected to a part of the vehicle body 12, and the ends on the side close to the wheel 14 are rotatably connected to the hub knuckle 62 connected to the wheel 14 via the ball joint 60. One end side of the hub knuckle 62 is rotatably connected to the upper arm 56, and the other end side is rotatably connected to the lower arm 58, so that it can swing in the vehicle width direction with the approximate center of the hub knuckle 62 as the center, allowing the wheel 14 to tilt in the vehicle width direction. The shock absorber 64 generates roll rigidity by expansion and contraction, and generates a force to resist the centrifugal force during turning, that is, a force to suppress the tilting vehicle 10 from shaking in the outer direction of the turn. Figure 4 In the case of, one end side (lower end side) of the shock absorber 64 is rotatably connected to the lower arm 58. In addition, in other embodiments, one end side (lower end side) of the shock absorber 64 may also be connected to the upper arm 56.

[0048] The other end side (upper end side) of the shock absorber 64 in the passive suspension 54 of the present embodiment is connected to a lever arm 66 extending in the vehicle width direction. The lever arm 66 is, for example, an arc-shaped plate member, and the upper end sides of the left and right shock absorbers 64 are rotatably connected at both ends. In addition, the central part of the lever arm 66 is rotatably connected to a part of the vehicle body 12. The lever arm 66 has a function of swinging before the shock absorber 64 is extended and retracted, so as to tilt the tilting vehicle 10. That is, the start of the extension and retraction action of the shock absorber 64 can be delayed. As a result, the tilting vehicle 10 can tilt the wheel 14 (front wheel) to the inner side of the turning direction (vehicle width direction) of the tilting vehicle 10 by an amount corresponding to the extension and retraction amount of the shock absorber 64 and the swing amount of the lever arm 66. In other words, the tilting amount of the wheel 14 (front wheel) can be extended to be greater than the extension and retraction capacity of the shock absorber 64, which helps to expand the stabilization range of the vehicle posture when turning.

[0049] In addition, the passive suspension 54 having the lever arm 66 can prevent the roll rigidity from being generated in the first region (first angle range) from the start of the tilt of the vehicle body 12 to the predetermined angle (swing range of the lever arm 66). In addition, the lever arm 66 (passive suspension 54) can generate the roll rigidity by the spring force of the shock absorber 64 in the second region (second angle range) further tilted from the first region. In other words, the passive suspension 54 of the present embodiment has different characteristics of the roll rigidity according to the degree of tilt of the tilting vehicle 10. In other words, the roll rigidity is reduced in order to give priority to the ease of tilting (easy tilting) in the area with a small tilt (first region), and the roll rigidity is increased by giving priority to the roll suppression in the area with a large tilt (second region). As a result, when the turning radius becomes larger and the vehicle speed becomes slower during turning, the centrifugal force generated in the outer direction of the turn is small, and the tilting posture of the tilting vehicle 10 is easily achieved. Furthermore, when the centrifugal force increases, the increased roll rigidity can reduce the instability of the tilting posture of the leaning vehicle 10 (the wheel 14 on the front wheel side) (the posture maintaining force can be improved).

[0050] use Figure 5 , Figure 6 The operation of the front wheel unit 16F configured in this manner will be described. Figure 5 1 is an illustrative and schematic image diagram showing a state in which the tilting vehicle 10 is not tilted in the vehicle width direction (inner direction of the turn) when the tilting vehicle 10 is viewed from the front side. Figure 6 1 is an illustrative and schematic image diagram showing a state in which the tilting vehicle 10 is tilted toward the inner side of the turn when the tilting vehicle 10 is viewed from the front side. In order to facilitate understanding of the behavior of the tilting vehicle 10, Figure 5 , Figure 6 The upper arm 56, the lower arm 58, the hub knuckle 62, the shock absorber 64, and the lever arm 66 of the front wheel unit 16F (passive suspension 54) are shown, and other components are omitted. Figure 2 , Figure 3 This is a view of the tilting vehicle 10 from the rear side. Figure 3 1 is a diagram showing a tilting vehicle 10 turning right. Figure 5 , Figure 6 This is a diagram of the tilting vehicle 10 as viewed from the front side. Figure 6 The tilting vehicle 10 is shown turning left.

[0051] As described above, the upper arm 56 and the lower arm 58 constituting the passive suspension 54 connect the wheel 14 (front wheel) and the vehicle body 12. The left and right upper arms 56 and the left and right lower arms 58 rotate in opposite directions to each other, thereby displacing the wheel 14 in the up-down direction according to the unevenness of the ground GL. In other words, the influence of the unevenness of the ground GL is suppressed from being transmitted to the vehicle body 12, which helps to improve comfort. In addition, the upper arm 56 and the lower arm 58 tilt the wheel 14 by rotating in the same direction, so that the vehicle body 12 can be tilted in the inner direction of the turn (vehicle width direction) relative to the ground GL in the same manner as the rear wheel unit 16R (rear link mechanism 50).

[0052] For example, Figure 5 When the tilting vehicle 10 is standing upright without tilting on the horizontal ground GL (i.e., the ground GL perpendicular to the vertical upward direction DU), as in the posture SF1, the upper arm 56 and the lower arm 58 are parallel to the horizontal direction. In this case, the shock absorber 64 is in a stable state and basically does not generate spring force. When the ground GL has unevenness, when the left and right wheels 14 are displaced in the upward direction or the downward direction at the same time, the left and right upper arms 56 and the left and right lower arms 58 rotate in opposite directions to absorb the displacement caused by the unevenness. In addition, when the ground GL has unevenness, when one of the wheels 14 is displaced in the upward direction or the downward direction according to the unevenness, the upper arm 56 and the lower arm 58 rotate in the same direction according to the unevenness to absorb the displacement caused by the unevenness. In addition, in this case, when the degree of unevenness is relatively small and the rotation amount of the lower arm 58 is within the swing range of the lever arm 66 connected to the shock absorber 64, the shock absorber 64 does not expand or contract, and the displacement caused by the unevenness is absorbed only by the swing of the lever arm 66, thereby stabilizing the posture of the vehicle body 12. On the other hand, when the degree of the unevenness exceeds the swing range of the lever arm 66 , the shock absorber 64 starts to expand and contract, and the displacement caused by the unevenness is absorbed by the swing of the lever arm 66 and the expansion and contraction of the shock absorber 64 .

[0053] Next, use Figure 6 , the behavior of the front wheel unit 16F (passive suspension 54) when the tilting vehicle 10 turns will be described. As described above, when the tilting vehicle 10 turns, for example, in the left direction DL, centrifugal force is generated in the outer direction of the turn (right direction DR). Therefore, it is necessary to tilt the tilting vehicle 10 toward the inner side of the turn to eliminate the centrifugal force. In this case, in the front wheel unit 16F, the left and right upper arms 56 and the left and right lower arms 58 rotate in the same direction, so that the wheels 14 are tilted and the vehicle body 12 is tilted relative to the ground GL toward the inner side of the turn (vehicle width direction).

[0054] For example, Figure 6As shown in the posture SF2 shown, when the tilting vehicle 10 turns left, the tilting vehicle 10 needs to tilt to the left direction as the inner side of the turn to balance the centrifugal force generated in the outer side of the turn. As mentioned above, the tilting vehicle 10 can intentionally tilt (lean) to the inner side of the turn by driving the tilt motor 52 on the side of the rear wheel unit 16R. In this case, the drive control of the tilt motor 52 is performed based on the target tilt angle (turning target information, target tilt angle) calculated according to the vehicle speed of the tilting vehicle 10 and the rotation angle (input angle) of the handle 26 and the actual tilt angle (actual tilt angle) obtained from the inertial measurement device. In this case, there is a case where the target tilt angle and the actual tilt angle are different depending on the driving state, road surface state, etc. Therefore, the tilting vehicle 10 controls the tilt motor torque generated by the tilt motor 52 of the rear wheel unit 16R to eliminate the deviation between the target tilt angle and the actual tilt angle, and realize the ideal turning posture of the tilting vehicle 10.

[0055] In the initial stage of the tilting of the tilting vehicle 10, in other words, when the centrifugal force is small, the front wheel unit 16F (passive suspension 54) does not extend or retract the lower arm 58 (upper arm 56) when the amount of rotation is within the swing range of the lever arm 66 connected to the shock absorber 64 (first region), and the shock absorber 64 is allowed to tilt the tilting vehicle 10 (wheel 14) only by the swing of the lever arm 66. In other words, if the tilt motor 52 generates a tilt motor torque to achieve the target tilt angle, the ideal turning posture of the tilting vehicle 10 can be easily achieved. On the other hand, when the centrifugal force becomes larger and the tilting of the tilting vehicle 10 toward the inner side of the turn needs to be increased, when the swing range of the lever arm 66 is exceeded (in the second region), the shock absorber 64 begins to extend or retract to generate a repulsive force, and the roll rigidity becomes larger to resist the increased centrifugal force. In this case, the shock absorber 64 on the inner side of the turn is compressed, and the shock absorber 64 on the outer side of the turn is extended. However, in this case, the repulsive force generated by the shock absorber 64 is balanced with the centrifugal force generated in the outer direction of the turn and is opposite to the control direction of the tilt motor 52 that tilts the tilting vehicle 10 in the inner direction of the turn, making it difficult to tilt the tilting vehicle 10 in the inner direction of the turn. In other words, it is difficult to achieve the ideal turning posture of the tilting vehicle 10 by only controlling the tilt motor 52 to the target tilt angle.

[0056] Therefore, the tilt motor 52 in the present embodiment is controlled based on the roll stiffness generated by the shock absorber 64 on the wheel unit side where the tilt unit is not mounted, so as to generate the tilt motor torque that cancels the roll stiffness.

[0057] Figure 71 is an illustrative and schematic block diagram showing the structure of the control device 24 for performing tilt control in the tilting vehicle 10. The control device 24 includes a target tilt angle acquisition unit 24a, an actual tilt angle acquisition unit 24b, a deviation acquisition unit 24c, a motor torque determination unit 24d, a drive control unit 24e, etc. The target tilt angle acquisition unit 24a can acquire a target tilt angle corresponding to the driving required by the driver based on the speed sensor 36 (vehicle speed of the tilting vehicle 10) and the rotation angle (input angle) of the handle 26, for example, by using a map prepared by a preliminary test. In addition, the actual tilt angle acquisition unit 24b can acquire an actual tilt angle representing the actual tilt state of the current tilting vehicle 10 through an inertial measurement device included in the direction sensor 28 provided on the rear wall 12e of the vehicle body 12. The deviation acquisition unit 24c calculates the deviation between the acquired target tilt angle and the actual tilt angle. Then, the motor torque determination unit 24d determines the tilt motor torque to eliminate the deviation between the target tilt angle acquired by the deviation acquisition unit 24c and the actual tilt angle. The drive control unit 24e drives and controls the tilt motor 52 so as to output the tilt motor torque determined by the motor torque determination unit 24d.

[0058] For example, when the actual tilt angle becomes smaller than the target tilt angle due to the repulsive force (roll stiffness) generated by the extension and contraction of the shock absorber 64, in other words, when the tilt of the tilting vehicle 10 is insufficient, the tilt motor 52 is corrected and controlled so as to generate a tilt motor torque in the direction of increasing the tilt. On the contrary, when the actual tilt angle becomes larger than the target tilt angle due to a sudden change in road conditions, in other words, when the tilt of the tilting vehicle 10 is too large, the tilt motor 52 is corrected and controlled so as to generate a tilt motor torque in the direction of reducing the tilt (raising the posture of the tilting vehicle 10). The value of the corrected tilt motor 52 at this time can be determined, for example, by using a map prepared by a preliminary test or the like. The map can establish a corresponding relationship between the tilt motor torque of the tilt motor 52 for eliminating the roll stiffness generated by the extension and contraction of the shock absorber 64, for example.

[0059] Therefore, according to the tilting type vehicle 10 of the present embodiment, the tilting motor 52 (tilting unit) is controlled in consideration of the repulsive force (roll stiffness) generated by the extension and contraction of the shock absorber 64, thereby realizing an ideal turning posture of the tilting type vehicle 10. As a result, the roll suppression based on the roll stiffness of the suspension (shock absorber 64) of the front wheel unit 16F and the tilt control based on the tilting unit of the rear wheel unit 16R can be performed with a good balance, and the tilting type vehicle 10 can be provided with a simple structure that can realize a more stable tilting posture when turning, and a structure that is easier to reduce costs can be provided.

[0060] In this way, by configuring the tilting unit on at least one of the front position (front wheel) and the rear position (rear wheel) of the tilting vehicle 10, and configuring the passive suspension 54 on the other wheel unit, the structure and control can be simplified compared with the configuration in which the tilting unit is configured on both the front position and the rear position to control both sides, so it can contribute to the cost reduction of the tilting vehicle 10. In addition, when the tilting unit is mounted on one of the front and rear wheel units and the passive suspension 54 that generates roll rigidity is mounted on the other wheel unit, the stable driving performance of the tilting vehicle 10 is maintained, and a stable tilting posture can be achieved when turning.

[0061] In addition, Figure 4 In the example shown, an example of using the lever arm 66 to expand the stabilization range of the vehicle posture when turning is shown. In other embodiments, a structure that does not have roll rigidity in the vicinity (first region) where the inclination (roll angle) of the vehicle body 12 is small can be used instead of the lever arm 66 to obtain the same effect. For example, by providing a passive stabilizer in a manner that there is an unloaded running interval, there is no roll rigidity in the vicinity (first region) where the roll angle is small, the extension and contraction action of the shock absorber 64 is delayed (in other words, the extension and contraction starts in the second region), and the overall inclination amount is increased to expand the stabilization range of the vehicle posture when turning. In addition, in this case, even when the centrifugal force generated in the outer direction of the turn is small, by not generating the roll rigidity in the first region, the tilting posture of the tilting vehicle 10 can be easily achieved. In addition, when the centrifugal force is large, by generating the roll rigidity based on the shock absorber 64 in the second region, the tilting posture of the tilting vehicle 10 (the wheel 14 on the front wheel side) can be reduced by the generated roll rigidity. In addition, as the spring element included in the passive suspension 54, a component whose generated roll rigidity changes in stages according to the telescopic state, such as a variable shock absorber, etc., can be used, or a component that can generate a small roll rigidity and a large roll rigidity can be used. In this case, even when the centrifugal force generated in the outer direction of the turn is small, the generated roll rigidity can be reduced, and the appropriate tilting posture of the tilting vehicle 10 can be easily achieved. In addition, when the centrifugal force is large, the roll rigidity generated in the second area can be increased, and the tilting posture of the tilting vehicle 10 (the wheel 14 on the front wheel side) can be reduced.

[0062] As described above, the tilting vehicle 10 of the present embodiment includes: a plurality of wheel units (rear wheel unit 16R, front wheel unit 16F) provided at least at the front and rear positions of the vehicle body 12, and provided with a pair of wheels 14 separated in the vehicle width direction; a tilting unit provided near one of the wheel units, and provided with a tilting mechanism (a mechanism for tilting the tilting vehicle 10 in the direction of the inner side of the turn) for tilting the wheel unit and the vehicle body 12 relative to the ground in the direction of the inner side of the turn and a tilting drive unit (tilt motor 52) for driving the tilting mechanism; and a passive suspension 54 (front link mechanism) provided at the other wheel unit of the wheel unit, and generating roll rigidity when the vehicle body 12 tilts in the vehicle width direction relative to the ground. According to this configuration, for example, the tilting unit is provided at one of the wheel units at least at the front and rear positions of the vehicle body 12, and the passive suspension 54 is provided at the other wheel unit. Therefore, it is possible to perform roll suppression based on the roll rigidity of the passive suspension 54 and tilt control based on the tilt unit with a good balance, and it is possible to provide a tilting vehicle with a simple structure and a more easily reduced cost structure that maintains stable driving performance and can achieve a more stable tilting posture when turning.

[0063] In the above-mentioned embodiment, the passive suspension 54 may have different characteristics of roll rigidity in the first region from the beginning of the tilt of the vehicle body 12 to a predetermined angle and in the second region further tilted from the first region. For example, the passive suspension 54 may slowly increase the roll rigidity in the first region where the tilt of the vehicle body 12 is small, and increase the change rate of the roll rigidity at a higher rate than that in the first region in the second region where the tilt exceeds the first region and becomes larger. In other words, the passive suspension 54 may also change so that the roll rigidity increases as the tilt of the vehicle body 12 increases. In addition, in other embodiments, the passive suspension 54 may not generate roll rigidity in the first region, and generate roll rigidity in the second region where the tilt increases. In other words, the roll rigidity of the passive suspension 54 may also be generated when the tilt of the vehicle body 12 (the wheel 14 on the front wheel side) exceeds a predetermined value. According to this configuration, the roll rigidity can be reduced in the first region where the tilt is small due to the priority tilt, and the roll rigidity can be increased by the priority roll suppression in the second region where the tilt is large. As a result, the roll suppression by the roll rigidity of the passive suspension 54 and the tilt control by the tilt unit are performed with a good balance, and a more stable tilting posture can be achieved when turning while maintaining stable running performance.

[0064] In the above-mentioned embodiment, the passive suspension 54 may also include a lower arm 58 and an upper arm 56 for supporting the wheel 14, a pair of spring members (shock absorbers 64) separated and arranged in the width direction and connected to either of the lower arm 58 and the upper arm 56 at the lower end, and a lever arm 66 connected to the upper ends of the pair of spring members at the ends in the vehicle width direction and rotatably connected to the vehicle body 12 at the center. According to this configuration, for example, it is easy to realize a structure that prioritizes tilting in a small tilt area (first area) without generating roll rigidity, and prioritizes roll suppression in a large tilt area (second area) to increase roll rigidity. In addition, it is easy to realize a structure that expands the tilt amount of the tilting vehicle 10 to more than the expansion and contraction capacity of the spring member (shock absorber 64) and expands the stabilization range of the vehicle posture when turning.

[0065] In the above-mentioned embodiment, the weight distribution of the vehicle body 12 may be distributed more to the wheel unit side having the tilt unit than to the wheel unit side having the suspension. According to this configuration, for example, the tilt motor torque generated by the tilt unit can be transmitted more to the road surface (ground GL), and the posture control performance of the tilt unit can be improved.

[0066] The embodiments and modifications of the present invention are described above, but the above-mentioned embodiments and modifications are only examples and are not intended to limit the scope of the invention. The above-mentioned new embodiments and modifications can be implemented in various ways, and various omissions, substitutions, and changes can be made without departing from the scope of the invention. The above-mentioned embodiments and modifications are included in the scope and spirit of the invention, and are included in the invention described in the claims and their equivalents.

Claims

1. A tilting vehicle, comprising: A plurality of wheel units are provided at least at the front and rear positions of the vehicle body and include a pair of wheels separated in the vehicle width direction; a tilting unit, which is arranged near one of the wheel units and comprises a tilting mechanism and a tilting drive unit, wherein the tilting mechanism tilts the wheel unit and the vehicle body relative to the ground toward the inner side of the turn, and the tilting drive unit is used to drive the tilting mechanism; The passive suspension is provided on the other wheel unit of the wheel unit and generates a roll stiffness when the vehicle body tilts in the vehicle width direction relative to the ground.

2. The tilting vehicle according to claim 1, wherein: The passive suspension has different rolling stiffness characteristics between a first region from the start of the inclination of the vehicle body to a predetermined angle and a second region where the vehicle body is further inclined from the first region.

3. The tilting vehicle according to claim 2, wherein: The passive suspension comprises: a lower arm and an upper arm, supporting the wheel; a pair of spring components, the lower ends of which are connected to either the lower arm or the upper arm, and are separated and arranged in the vehicle width direction; and a lever arm, the ends of which are respectively connected to the upper ends of the pair of spring components in the vehicle width direction, and the central portion of the lever arm is rotatably connected to the vehicle body.

4. The tilting vehicle according to claim 1, wherein: The weight distribution of the vehicle body is distributed more to the wheel unit side provided with the tilting unit than to the wheel unit side provided with the passive suspension.

Images