TWM602522U - Electric three-wheeled vehicle - Google Patents

Abstract

Provide electric tricycles that can achieve good steering performance. The electric tricycle has: a first motor, which applies driving force to the left wheel around the first axis; a second motor, which applies driving force to the right wheel arranged side by side with the left wheel around the second axis; and a steering sensor, which applies driving force to the handlebar The steering angle is detected; a tilt sensor that detects the tilt of the frame relative to the direction of gravity in the left and right direction of the car body; and the controller, which generates when the tilt exceeds a predetermined value, based on the steering angle of the handlebar A control signal of driving force greater than that of the inner wheel is applied to the outer wheel.

Description

Electric tricycle

Creative field

This creation relates to an electric tricycle. The electric tricycle has: a left wheel, which is supported by a frame to rotate freely around a first axis; a right wheel, which is side by side with the left wheel and is supported by a frame to rotate freely around a second axis; and a handlebar, which is The frame support is rotatable and is operated by the occupant to change any one or more directions of the wheels including the left wheel and the right wheel.

Creative background

Patent Document 1 discloses an electric tricycle having a left front wheel supported by a frame so as to be rotatable about a first axis, and a right front wheel juxtaposed with the left front wheel and supported by the frame so as to be rotatable about a second axis. When turning, the outer wheel follows a track with a smaller curvature than the inner wheel.

Patent Document 1: Japanese Patent Application Publication No. 2010-184508

Creation summary [Problems to be solved by creation]

In the electric tricycle described in Patent Document 1, since the left front wheel and the right front wheel are respectively supported by the front forks, although the rotation difference between the outer wheel and the inner wheel is passively absorbed, it is not practical to ensure good steering performance. Difficult to turn. The decrease in steering performance will lead to a decline in the commercial power of electric tricycles.

This creation was completed in view of the above-mentioned actual situation, and its purpose is to provide an electric tricycle that can achieve good steering performance. [Means used to solve the problem]

According to the first aspect of the present invention, there is provided an electric tricycle, which has: a left wheel supported by a frame so as to be freely rotatable about a first axis; a right wheel, parallel to the left wheel, supported by the frame so as to rotate about a second axis The handlebar, which is rotatably supported by the frame, is operated by the occupant to change any one or more directions of the wheels including the left wheel and the right wheel; the first electric motor is for the left wheel A driving force is applied around the first axis; a second electric motor, which applies a driving force to the right wheel around the second axis; a steering sensor, which detects the steering angle of the handlebar; tilt sensing A device that detects the tilt of the frame relative to the direction of gravity in the left and right direction of the vehicle body; and a controller that generates an outer wheel based on the steering angle of the handlebar when the tilt exceeds a predetermined value A control signal of driving force greater than that of the inner wheel is applied.

According to a second aspect, in addition to the structure of the first aspect, when the inclination is less than or equal to a predetermined value, the controller generates, based on the steering angle of the handlebar, a driving force that is applied to the inner wheel than the outer wheel Large driving force control signal.

According to a third aspect, in addition to the structure of the first or second aspect, the frame supports the left wheel and the right wheel so as to be freely displaceable in the vertical direction.

According to the fourth aspect, in addition to the structure of the first or second aspect, the frame has a structure that allows the center of gravity of the occupant to move outward from the space sandwiched by the first virtual vertical surface and the second virtual vertical surface , Wherein the first imaginary vertical surface is perpendicular to the first axis and passes through the grounding point of the revolver and the ground when traveling straight on flat ground, and when traveling straight on flat ground, the second imaginary vertical surface The second axis is vertical and passes through the grounding point of the right wheel and the ground. [New Effect]

According to the first aspect, when the inclination of the vehicle body exceeds a predetermined value, it is inferred that the occupant intends to turn. Generally, the occupant leans the body in the turning direction to move the center of gravity. At this time, when the steering angle of the handlebar is detected, by applying a larger driving force to the outer wheel than the inner wheel, it is possible to intentionally generate a rotational speed difference between the inner wheel and the outer wheel when turning. The vehicle can turn smoothly. Can improve the stability of behavior when turning. Able to achieve good steering.

According to the second aspect, when the inclination of the vehicle body is less than or equal to a predetermined value, it is inferred that the occupant intends to travel straight. At this time, when the steering of the handlebar is detected, it is possible to return the handlebar to the straight direction by applying a larger driving force to the inner wheel than the outer wheel. In this way, the straight running stability is improved. Generally, when driving straight, the occupant of the two-wheeled vehicle makes up for the deviation of the center of gravity in the left-right direction by turning the handlebar. By using the functions of the first electric motor and the second electric motor to assist the steering of such a handlebar, it is possible to improve the straight running stability. The stability of the behavior during driving can be improved. When driving straight and when turning, by switching the magnitude relationship of the driving force between the inner wheel and the outer wheel, the stability of the behavior during driving can be improved well.

According to the third aspect, the left wheel and the right wheel can be respectively displaced in the vertical direction of the vehicle body in accordance with the reaction force from the ground. By making the driving force of the left wheel and the right wheel different, the displacement of the left wheel or the right wheel can be caused. In this way, the posture of the vehicle body can be further stabilized.

According to the fourth aspect, since the movement range of the distance between the left wheel and the right wheel with respect to the center of gravity of the occupant is narrowed, the electric tricycle can ensure an appearance similar to that of a general two-wheeled bicycle. In this way, the appearance of the electric tricycle can be improved.

Detailed description of the preferred embodiment

Hereinafter, an embodiment of this creation will be described with reference to the drawings. In addition, in the following description, the directions of front and rear, up and down, and left and right refer to directions viewed from an occupant riding a tricycle.

Fig. 1 schematically shows the overall structure of an electric-assisted three-wheeled bicycle 11 according to an embodiment of the present creation. The three-wheeled bicycle 11 has a steering system 13 which supports the left front wheel 12a and the right front wheel 12b arranged side by side; and a frame 15 which is connected to the steering system 13 at the front end and separates a single rear at a position away from the front end to the rear. The wheel 14 is rotatably supported. The frame 15 has: a front riser 15a, which is arranged above the left front wheel 12a and the right front wheel 12b; a down tube 15b, which extends rearward from the front riser 15a; and a seat tube 15c, which extends from the down tube behind the front riser 15a 15b extends upward; and a chain bracket 15d, which extends further rearward from the down tube 15b, and supports the rear wheel 14 to be rotatable about the axis Xr. When the axis Xr of the rear wheel 14 is in the horizontal direction, the self-standing posture of the frame 15 is ensured. At this time, the left and right center surfaces of the frame 15 coincide with the vertical surface.

A seat 16 is supported at the upper end of the seat tube 15c. The seat 16 is fixed to a seat post 17 inserted in the seat tube 15c. The seat 16 receives the buttocks of the occupant.

A human power driving system 18 is combined with the frame 15, and the human power driving system 18 uses the human power of the occupant to drive the rear wheel 14 around the axis Xr. The human power drive system 18 has: a crank 19, which is rotatably supported by the down tube 15b between the front riser 15a and the seat tube 15c; a drive sprocket 21, which is fixed to the crank 19 coaxially with the rotation axis Xk of the crank 19; The driven sprocket 22 is fixed to the rear wheel 14 coaxially with the axis Xr of the rear wheel 14; and the chain 23 is wound around the driving sprocket 21 and the driven sprocket 22. The crank 19 has a drive shaft 19a that has a shaft center parallel to the axis Xr of the rear wheel 14 and is rotatably supported by a bearing of the down tube 15b; and a left arm 19b that protrudes to the left from the down tube 15b relative to the drive shaft 19a One end is coupled to the drive shaft 19a and extends in the centrifugal direction; and the right arm 19c, which is coupled to the other end of the drive shaft 19a protruding to the right from the lower tube 15b, extends from the drive shaft 19a in the centrifugal direction. The left arm 19b and the right arm 19c are arranged at an interval of 180 degrees around the axis of the drive shaft 19a. A pedal 24 is connected to the tips of the left arm 19b and the right arm 19c, respectively. The pedal 24 is supported by the left arm 19b and the right arm 19c so as to be rotatable about a rotation axis parallel to the axis of the drive shaft 19a. The occupant can place the left and right feet on the left and right pedals 24 while sitting on the seat 16.

The steering system 13 has: a front fork 25, which is rotatably connected to the front riser 15a about a steering axis Sx, the steering axis Sx shifts rearward as it goes upward; a handlebar 26, as shown in FIG. 2 As shown, it is connected to the front fork 25 at a position higher than the front riser 15a and extends in the left-right direction; the rear wheel brake lever 27 is swingably mounted on the left end of the handlebar 26, and the brake of the rear wheel 14 The front wheel brake lever 28, which is swingably mounted on the right end of the handlebar 26, is connected to the brakes of the front wheels 12a, 12b; and the linkage mechanism 29, which is free to change its posture relative to the front fork 25 with the front fork 25 is connected to support the left front wheel 12a and the right front wheel 12b. A handle 31 is fixed to the left and right ends of the handlebar 26, respectively. The rear brake lever 27 extends in parallel with the handle 31 on the left side. The left hand of the occupant can operate the rear wheel brake lever 27 while holding the handle 31. The front wheel brake lever 28 extends in parallel with the handle 31 on the right side. The right hand of the occupant can operate the front wheel brake lever 28 while holding the handle 31.

The link mechanism 29 has: a support member 32 that is rotatably connected to the front fork 25 in the rolling direction about a horizontal axis Hx, and extends from the horizontal axis Hx in the left-right direction, and the horizontal axis Hx extends in the front-rear direction; The steering knuckle 33 is supported by the support member 32 at a position on the left side of the horizontal axis Hx so as to be rotatable about a connecting axis Xp parallel to the horizontal axis Hx; the right steering knuckle 34 is at a position on the right side of the horizontal axis Hx The supported member 32 is supported so as to be rotatable about a connection axis Xq parallel to the horizontal axis Hx; and a link arm 35 which connects the left knuckle 33 and the right knuckle 34 to each other. The link arm 35 is coupled to the left steering knuckle 33 and the right steering knuckle 34 so as to be freely swingable about a swing axis, which is parallel to the connection axis Xp, Xq. In this way, a quadrilateral link mechanism 29 with four joints is established. By the action of the link arm 35, the movements of the left steering knuckle 33 and the right steering knuckle 34 around the connecting axes Xp and Xq are linked. Furthermore, since the link mechanism 29 rotates about the horizontal axis Hx, the left front wheel 12a and the right front wheel 12b are relatively displaced in the vertical direction with respect to the front fork 25.

The hub 36 of the left front wheel 12a is connected to the left knuckle 33 so as to be rotatable about the axis Xff. The hub 36 of the right front wheel 12b is coupled to the right knuckle 34 so as to be rotatable about the axis Xfs. The frame 15 has a structure that allows the center of gravity of the occupant to move outward from the space sandwiched by the first virtual vertical surface Vf and the second virtual vertical surface Vs. The first virtual vertical surface Vf travels straight on flat ground. It is perpendicular to the axis Xff and passes through the grounding point of the left front wheel 12a and the ground. When the second imaginary vertical plane Vs travels straight on flat ground, it is perpendicular to the axis Xfs and passes through the grounding point of the right front wheel 12b and the ground. As shown in Figure 1, the left front wheel 12a, the right front wheel 12b, and the rear wheel 14 are respectively formed by a hub 36, a rim 38 and a rubber tire 39. The rim 38 is coaxial with the hub 36 and is connected to the hub 36 by spokes 37. The rubber The tire 39 is mounted on the rim 38.

As shown in FIG. 3, an electric drive system 42 is combined with the three-wheeled bicycle 11, and the electric drive system 42 drives the left front wheel 12a and the right front wheel 12b around the axes Xff and Xfs using the driving force generated by electric power. The electric drive system 42 includes a first electric motor 43 connected to the left front wheel 12a and applying a driving force to the left front wheel 12a in response to the supply of electric power; and a first driver circuit 44 connected to the first electric motor 43 and opposed to the first electric motor 43 to control the power provided; the second motor 45, which is connected to the right front wheel 12a, applies driving force to the right front wheel 12a according to the supply of power; the second driver circuit 46, which is connected to the second motor 45, opposes the second The electric power supplied by the motor 45 is controlled; and the battery 47 is connected to the first driver circuit 44 and the second driver circuit 46 and stores the electric power supplied to the first driver circuit 44 and the second driver circuit 46. For the first motor 43 and the second motor 45, for example, a direct current (DC) brushless motor can be used. The first electric motor 43 and the second electric motor 45 may be directly connected to the axles of the left front wheel 12a and the right front wheel 12b, or may be indirectly connected via a gear mechanism. Electric power is supplied from the battery 47 to the first motor 43 and the second motor 45, respectively. Therefore, the driving forces of the left front wheel 12a and the right front wheel 12b are respectively set.

The electric drive system 42 also has: a controller 48 connected to the first driver circuit 44 and the second driver circuit 46 to control the operations of the first driver circuit 44 and the second driver circuit 46; and a left front wheel speed sensor 51 , Which detects the rotation speed of the left front wheel 12a, and provides the detected left front wheel speed to the controller 48; the right front wheel speed sensor 52, which detects the rotation speed of the right front wheel 12b, and detects The right front wheel speed is provided to the controller 48; the rear wheel speed sensor 53, which detects the vehicle speed according to the rotation speed of the rear wheel 14 and provides the detected vehicle speed to the controller 48; the pedal force sensor 54, which The pedaling force acting on the crank 19 is detected, and the detected pedaling force is provided to the controller 48; the steering sensor 55 detects the steering angle of the handlebar 26 relative to the front riser 15a, and detects The steering angle detected is provided to the controller 48; the tilt sensor 56 detects the tilt angle of the seat tube 15c with respect to the vertical direction (gravity direction), and provides the detected tilt angle to the controller 48; and The slope sensor 57 detects the inclination angle of the road surface in the left-right direction with respect to the horizontal plane perpendicular to the vertical direction, and provides the detected inclination angle of the road surface to the controller 48.

The rear wheel speed sensor 53 is attached to, for example, a bearing of the rear wheel 14 and outputs an electric signal for determining the vehicle speed based on the rotation speed of the rear wheel 14. The steering sensor 55 is mounted on the front riser 15a, for example, and outputs an electrical signal that determines the rotation angle of the front fork 25 about the steering axis Sx. The tilt sensor 56 is attached to the seat tube 15c, for example, and outputs an electric signal for determining the tilt angle in the left-right direction with respect to a vertical plane perpendicular to the axis Xr of the rear wheel 14 when traveling straight on flat ground. The tilt sensor 56 can use, for example, a gyroscope sensor. The slope sensor 57 is attached to the front fork 25, for example, and outputs an electrical signal that determines the inclination angle of the link mechanism 29 about the horizontal axis Hx of the support member 32. The controller 48, the rear wheel speed sensor 53, the steering sensor 55, the tilt sensor 56, and the slope sensor 57 are supplied with operating power from the battery 47.

The controller 48 includes a memory 48a. The memory 48a stores, for example, a look-up table that distributes the rotation speed (per minute) of the motor to the pedaling force. In the look-up table, the current value that realizes the assigned speed (per minute) is specified according to the size of the pedaling force.

When driving, the occupant straddles the seat 16 of the tricycle 11 that stands on its own. The occupant holds the left handle 31 with his left hand, and the right handle 31 with his right hand. The occupant places his left foot and right foot on the left and right pedals 24, respectively. When the occupant steps on the pedal 24, the pedaling force of the occupant acts on the crank 19. The crank 19 rotates about the rotation axis Xk. The rotation of the crank 19 is transmitted to the rear wheel 14 through the actions of the driving sprocket 21, the chain 23 and the driven sprocket 22. In this way, the rotation of the rear wheel 14 is caused by the driving force of the human power. The tricycle 11 moves forward.

When the switch of the controller 48 is turned on, the controller 48 performs electric assist control. As shown in FIG. 4, during driving, in step S1, the controller 48 detects the driving speed. At the time of detection, a signal is provided from the rear wheel speed sensor 53 to the controller 48. If it is determined that the traveling speed exceeds the predetermined speed, the controller 48 performs cruise control in step S2. When the predetermined speed is exceeded, the posture and behavior of the three-wheeled bicycle 11 are stable under the action of the inertial force in the forward direction. Therefore, the controller 48 controls the driving of the left front wheel 12a and the right front wheel 12b according to the stable posture and behavior. The details of cruise control will be described later.

In step S1, if the traveling speed is less than or equal to a predetermined speed, the controller 48 performs stepping control in step S3. Since the posture and behavior of the three-wheeled bicycle 11 are unstable when pedaling, the driving of the left front wheel 12a and the right front wheel 12b is controlled based on the instability of the posture and behavior. The details of the stepping control will be described later.

As shown in FIG. 5, during cruise control, the controller 48 performs step T1 on the inclination angle of the seat tube 15c in the left-right direction with respect to the vertical plane perpendicular to the axis Xr of the rear wheel 14 when traveling straight on flat ground. Detection. At the time of detection, a signal is provided from the tilt sensor 56 to the controller 48. If the inclination of the seat tube 15c is less than or equal to the predetermined inclination angle, the controller 48 performs straight travel control in step T2. When the inclination of the seat tube 15c is less than or equal to the predetermined inclination angle, it is inferred that the occupant intends to travel straight. The controller 48 controls the driving of the left front wheel 12a and the right front wheel 12b to improve the straight running stability of the three-wheeled bicycle 11. The details of the straight travel control will be described later.

In step T1, if it is determined that the inclination of the seat tube 15c exceeds the predetermined inclination angle, the controller 48 performs turning control in step T3. When the inclination of the seat tube 15c exceeds the predetermined inclination angle, it is inferred that the occupant intends to turn. Generally, the occupant leans the body in the turning direction to move the center of gravity. Therefore, the controller 48 controls the driving of the left front wheel 12a and the right front wheel 12b based on the difference in rotational speed generated between the left front wheel 12a and the right front wheel 12b when turning. In this way, the stability of the behavior when turning is improved. The details of the turning control will be described later.

As shown in FIG. 6, when the straight travel control is executed, the controller 48 detects the steering angle of the handlebar 26 in step V1. At the time of detection, a signal is provided from the steering sensor 55 to the controller 48. When it is determined from the steering angle that the left front wheel 12a is the inner wheel, in step V2, the controller 48 generates a control signal for applying a driving force greater than that of the right front wheel 12b to the left front wheel 12a. When the control signal is generated, the value of the current supplied to the first motor 43 is obtained from the look-up table according to the magnitude of the pedaling force. By multiplying the acquired current value by a coefficient (<1), the current value supplied to the second electric motor 45 is determined. As long as the tilt angle (or steering angle) is larger, the coefficient is smaller.

In the next step V3, the control signal is supplied to the first driver circuit 44 and the second driver circuit 46. The first driver circuit 44 supplies a current to the first motor 43 in accordance with a current value designated based on the control signal. The first motor 43 drives the left front wheel 12a. The second driver circuit 46 supplies a current to the second motor 45 in accordance with a current value designated based on the control signal. The second motor 45 drives the right front wheel 12b. Even if the handlebar 26 is turned to the left at a slight angle, the handlebar 26 will return to the straight direction by applying a greater driving force to the left front wheel 12a (inner wheel) than the right front wheel 12b (outer wheel).

In step V1, when it is determined from the steering angle that the right front wheel 12b is the inner wheel, in step V4, the controller 48 generates a control signal for applying a driving force greater than that of the left front wheel 12a to the right front wheel 12b. When the control signal is generated, the current value supplied to the second motor 45 is obtained from the look-up table according to the magnitude of the pedaling force. By multiplying the obtained current value by a coefficient (<1), the current value supplied to the first electric motor 43 is determined.

In the next step V3, the control signal is supplied to the first driver circuit 44 and the second driver circuit 46. The first driver circuit 44 supplies a current to the first motor 43 in accordance with a current value designated based on the control signal. The first motor 43 drives the left front wheel 12a. The second driver circuit 46 supplies a current to the second motor 45 in accordance with a current value designated based on the control signal. The second motor 45 drives the right front wheel 12b. Even if the handlebar 26 is turned to the right at a slight angle, the handlebar 26 will return to the straight direction by applying a greater driving force to the right front wheel 12b (inner wheel) than the left front wheel 12a (outer wheel).

As described above, when the inclination of the seat tube 15c is less than or equal to a predetermined value, it is inferred that the occupant intends to travel straight. At this time, if the steering of the handlebar 26 is detected, the handlebar 26 is returned to the straight direction by applying a larger driving force to the inner wheel than the outer wheel. In this way, the straight running stability is improved. Generally, when driving straight, the occupant of the two-wheeled vehicle makes up for the deviation of the center of gravity in the left-right direction by turning the handle. By using the functions of the first electric motor 43 and the second electric motor 45 to assist the steering of such a handlebar 26, the straight running stability is improved. The stability of the behavior during driving can be improved.

As shown in FIG. 7, when the turning control is executed, the controller 48 detects the steering angle of the handlebar 26 in step W1. At the time of detection, a signal is provided from the steering sensor 55 to the controller 48. When it is determined from the steering angle that the left front wheel 12a is the inner wheel, in step W2, the controller 48 generates a control signal for applying a driving force greater than that of the left front wheel 12a to the right front wheel 12b. When the control signal is generated, the current value supplied to the second motor 45 is obtained from the look-up table according to the magnitude of the pedaling force. By multiplying the obtained current value by a coefficient (<1), the current value supplied to the first electric motor 43 is determined. As long as the tilt angle (or steering angle) is larger, the coefficient is smaller.

In the next step W3, the control signal is supplied to the first driver circuit 44 and the second driver circuit 46. The first driver circuit 44 supplies a current to the first motor 43 in accordance with a current value designated based on the control signal. The first motor 43 drives the left front wheel 12a. The second driver circuit 46 supplies a current to the second motor 45 in accordance with a current value designated based on the control signal. The second motor 45 drives the right front wheel 12b. By applying a larger driving force to the right front wheel 12b (outer wheel) than the left front wheel 12a (inner wheel), a difference in rotational speed is intentionally generated between the inner wheel and the outer wheel when turning.

When it is determined in step W1 that the left front wheel 12a is an outer wheel based on the steering angle, in step W4, the controller 48 generates a control signal for applying a driving force greater than that of the right front wheel 12b to the left front wheel 12a. When the control signal is generated, the value of the current supplied to the first motor 43 is obtained from the look-up table according to the magnitude of the pedaling force. By multiplying the acquired current value by a coefficient (<1), the current value supplied to the second electric motor 45 is determined.

In the next step W3, the control signal is supplied to the first driver circuit 44 and the second driver circuit 46. The first driver circuit 44 supplies a current to the first motor 43 in accordance with a current value designated based on the control signal. The first motor 43 drives the left front wheel 12a. The second driver circuit 46 supplies a current to the second motor 45 in accordance with a current value designated based on the control signal. The second motor 45 drives the right front wheel 12b. By applying a larger driving force to the left front wheel 12a (outer wheel) than the right front wheel 12b (inner wheel), a difference in rotation speed is intentionally generated between the inner wheel and the outer wheel when turning.

As described above, when the inclination of the seat tube 15c exceeds a predetermined value, it is inferred that the occupant intends to turn. Generally, the occupant leans the body in the turning direction to move the center of gravity. At this time, if the steering angle of the handlebar 26 is detected, by applying a larger driving force to the outer wheel than the inner wheel, it is possible to intentionally generate a rotation speed difference between the inner wheel and the outer wheel when turning. The vehicle can turn smoothly. Can improve the stability of behavior when turning. Able to achieve good steering. When driving straight and when turning, by switching the magnitude relationship of the driving force between the inner wheel and the outer wheel, the stability of the behavior during driving can be improved well.

Here, the occupant usually leans in the turning direction to move the center of gravity. The greater the curvature of the turn, the greater the distance the center of gravity moves. If the moving distance of the center of gravity becomes larger, the inclination of the seat tube 15c becomes larger. Therefore, if the difference in driving force between the inner wheel and the outer wheel is increased in accordance with the inclination of the seat tube 15c, the vehicle can turn smoothly in accordance with the curvature of the turn. Can improve the stability of behavior when turning. The stability of the behavior during driving can be improved.

In cruise control, it is also possible to superimpose the slope travel control during straight travel control. As shown in FIG. 8, when the slope driving control is executed, the controller 48 detects the inclination angle of the road surface in step Q1. At the time of detection, a signal is provided from the slope sensor 57 to the controller 48. When it is determined from the inclination angle of the road surface that the left front wheel 12a is the lower wheel, in step Q2, the controller 48 generates a control signal for applying a driving force greater than that of the right front wheel 12b to the left front wheel 12a. When the control signal is generated, the value of the current supplied to the first motor 43 is obtained from the look-up table according to the magnitude of the pedaling force. By multiplying the acquired current value by a coefficient (<1), the current value supplied to the second electric motor 45 is determined. As long as the tilt angle is larger, the coefficient is smaller.

In the next step Q3, the control signal is supplied to the first driver circuit 44 and the second driver circuit 46. The first driver circuit 44 supplies a current to the first motor 43 in accordance with a current value designated based on the control signal. The first motor 43 drives the left front wheel 12a. The second driver circuit 46 supplies a current to the second motor 45 in accordance with a current value designated based on the control signal. The second motor 45 drives the right front wheel 12b. When driving on an inclined surface inclined in the left-right direction, by applying a larger driving force to the left front wheel 12a (lower wheel) than the right front wheel 12b (upper wheel), the left front wheel 12a and the right front wheel 12b are applied to overcome and descend along the inclined surface. The driving force of the force. In this way, the straight running stability is improved. The stability of the behavior during driving can be improved.

In step Q1, when it is determined from the inclination angle of the road surface that the right front wheel 12b is the lower wheel, in step Q4, the controller 48 generates a control signal for applying a driving force greater than that of the left front wheel 12a to the right front wheel 12b . When the control signal is generated, the current value supplied to the second motor 45 is obtained from the look-up table according to the magnitude of the pedaling force. By multiplying the obtained current value by a coefficient (<1), the current value supplied to the first electric motor 43 is determined.

In the next step Q3, the control signal is supplied to the first driver circuit 44 and the second driver circuit 46. The first driver circuit 44 supplies a current to the first motor 43 in accordance with a current value designated based on the control signal. The first motor 43 drives the left front wheel 12a. The second driver circuit 46 supplies a current to the second motor 45 in accordance with a current value designated based on the control signal. The second motor 45 drives the right front wheel 12b. When driving on a slope inclined in the left-right direction, by applying a greater driving force to the right front wheel 12b (lower wheel) than the left front wheel 12a (upper wheel), the left front wheel 12a and the right front wheel 12b are applied to overcome and descend along the slope The driving force of the force. In this way, the straight running stability is improved. The stability of the behavior during driving can be improved.

As shown in FIG. 9, when the stepping control is performed, in step R1, the controller 48 detects the rotation speed of the left front wheel 12a and the rotation speed of the right front wheel 12b. At the time of detection, signals are provided to the controller 48 from the left front wheel speed sensor 51 and the right front wheel speed sensor 52. If the rotation speed of the left front wheel 12a is lower than the rotation speed of the right front wheel 12b, in step R2, the controller 48 generates a control signal based on the rotation speed of the left front wheel 12a. In the control signal, the current value to be supplied to the first electric motor 43 and the second electric motor 45 is determined based on the magnitude of the pedaling force (manpower).

In the next step R3, the control signal is supplied to the first driver circuit 44 and the second driver circuit 46. The first driver circuit 44 supplies a current to the first motor 43 in accordance with a current value designated based on the control signal. The first motor 43 drives the left front wheel 12a. The second driver circuit 46 supplies a current to the second motor 45 in accordance with a current value designated based on the control signal. The second motor 45 drives the right front wheel 12b.

If the rotation speed of the left front wheel 12a is equal to or higher than the rotation speed of the right front wheel 12b, in step R4, the controller 48 generates a control signal based on the rotation speed of the right front wheel 12b. In the control signal, the current value to be supplied to the first electric motor 43 and the second electric motor 45 is determined based on the magnitude of the pedaling force (manpower).

In the next step R3, the control signal is supplied to the first driver circuit 44 and the second driver circuit 46. The first driver circuit 44 supplies a current to the first motor 43 in accordance with a current value designated based on the control signal. The first motor 43 drives the left front wheel 12a. The second driver circuit 46 supplies a current to the second motor 45 in accordance with a current value designated based on the control signal. The second motor 45 drives the right front wheel 12b.

When pedaling is started from a stationary state, since the inertial force has not sufficiently increased in the forward direction, the center of gravity is shifted in the left-right direction, and the force of shaking in the left-right direction acts on the tricycle 11. At this time, even if the first motor 43 and the second motor 45 are separately controlled according to the inclination of the seat tube 15c, such control does not contribute to the stabilization of the posture. Will consume electricity in vain. If one rotation speed is set in common for the left front wheel 12a and the right front wheel 12b, waste of control can be eliminated, and power consumption can be saved.

In the present embodiment, the frame 15 supports the left front wheel 12a and the right front wheel 12b so as to be freely displaceable in the vertical direction. According to the reaction force from the ground, the left front wheel 12a and the right front wheel 12b can be displaced in the vertical direction of the vehicle body, respectively. By making the driving forces of the left front wheel 12a and the right front wheel 12b different, the displacement of the left front wheel 12a or the right front wheel 12b can be caused. In this way, the posture of the vehicle body can be further stabilized.

The frame 15 of this embodiment has a structure that allows the center of gravity of the occupant to move outward from the space sandwiched by the first virtual vertical surface Vf and the second virtual vertical surface Vs, wherein the first virtual vertical surface Vf is on a flat ground. When traveling straight on the upper side, it is perpendicular to the axis Xff and passes through the grounding point of the left front wheel 12a and the ground. When traveling straight on the flat ground, the second imaginary vertical plane Vs is perpendicular to the axis Xfs and passes the grounding point of the right front wheel 12b and the ground. Since the movement range of the distance between the left front wheel 12a and the right front wheel 12b with respect to the center of gravity of the occupant becomes narrow, the three-wheeled bicycle 11 can ensure an appearance similar to that of a general two-wheeled bicycle. In this way, the appearance of the three-wheeled bicycle 11 can be improved.

11: Electric tricycle (electric assisted tricycle)

12a: Left wheel (left front wheel)

12b: Right wheel (right front wheel)

13: steering system

14: rear wheel

15: Frame

15a: riser

15b: Down tube

15c: seat tube

15d: chain bracket

16: car seat

17: Seat post

18: Human drive system

19: crank

19a: drive shaft

19b: left arm

19c: right arm

21: drive sprocket

22: driven sprocket

23: chain

24: Pedal

25: Fork

26: Handlebar (Handlebar)

27: Rear wheel brake lever

28: Front wheel brake lever

29: Linkage mechanism

31: handle

32: Supporting parts

33: Left Knuckle

34: Right Knuckle

35: Link arm

36: Wheel hub

37: spokes

38: Rim

39: rubber tires

42: Electric drive system

43: 1st motor

44: The first driver circuit

45: 2nd motor

46: 2nd driver circuit

47: battery

48: Controller

48a: memory device

51: Left front wheel speed sensor

52: Right front wheel speed sensor

53: Rear wheel speed sensor

54: Pedal force sensor

55: steering sensor

56: Tilt sensor

57: Incline sensor

Hx: horizontal axis

Xff: the first axis (the axis of the left front wheel)

Xfs: 2nd axis (the axis of the right front wheel)

Xk: axis of rotation

Xp, Xq: connecting axis

Xr: axis

Sx: Around the steering axis

Vf: The first imaginary vertical plane

Vs: The second imaginary vertical plane

S1~S3, V1~V4, T1~T3, W1~W4, Q1~Q4, R1~R4: steps

FIG. 1 is a side view schematically showing the overall structure of an electric tricycle according to an embodiment of the invention, that is, an electric assisted three-wheeled bicycle. Figure 2 is a front view of a three-wheeled bicycle. Fig. 3 is a block diagram schematically showing the structure of an electric drive system. Fig. 4 is a flowchart schematically showing the processing operation of the controller. Fig. 5 is a flowchart schematically showing a processing operation of cruise control. Fig. 6 is a flowchart schematically showing the processing operation of the straight travel control. Fig. 7 is a flowchart schematically showing a processing operation of turning control. Fig. 8 is a flowchart schematically showing the processing operation of the slope traveling control. Fig. 9 is a flowchart schematically showing the processing operation of stepping control.

12a: Left wheel (left front wheel)

12b: Right wheel (right front wheel)

14: rear wheel

15c: seat tube

19: crank

26: Handlebar (Handlebar)

29: Linkage mechanism

42: Electric drive system

43: 1st motor

44: The first driver circuit

45: 2nd motor

46: 2nd driver circuit

47: battery

48: Controller

48a: memory device

51: Left front wheel speed sensor

52: Right front wheel speed sensor

53: Rear wheel speed sensor

54: Pedal force sensor

55: steering sensor

56: Tilt sensor

57: Incline sensor

Claims (4)

An electric tricycle, characterized in that: The electric tricycle has: The revolver, which is supported by the frame to rotate freely around the first axis; The right wheel, which is side by side with the left wheel, is supported by the frame so as to rotate freely around the second axis; A handlebar, which is supported by the frame for free rotation, and is operated by an occupant to change any one or more directions of the wheels including the left wheel and the right wheel; A first motor, which applies a driving force to the left wheel around the first axis; A second motor that applies a driving force to the right wheel around the second axis; A steering sensor, which detects the steering angle of the handlebar; A tilt sensor that detects the tilt of the frame relative to the direction of gravity in the left-right direction of the vehicle body; and The controller generates a control signal for applying a driving force greater than that of the inner wheel to the outer wheel based on the steering angle of the handlebar when the inclination exceeds a predetermined value. The electric tricycle according to claim 1, characterized in that: When the tilt is equal to or less than a predetermined value, the controller generates a control signal for applying a driving force greater than that of the outer wheel to the inner wheel based on the steering angle of the handlebar. The electric tricycle according to claim 1 or 2, characterized in that: The frame supports the left wheel and the right wheel so as to be freely displaceable in the vertical direction. The electric tricycle according to claim 1 or 2, characterized in that: The frame has a structure that allows the center of gravity of the occupant to move outward from the space sandwiched by the first imaginary vertical surface and the second imaginary vertical surface. The first axis is vertical and passes through the grounding point of the left wheel and the ground, and the second imaginary vertical plane is perpendicular to the second axis and passes through the grounding point of the right wheel and the ground when running straight on flat ground.

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