JP3407981B2 - Electric bicycle - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to both a human-powered driving unit and an electric-powered driving unit. The present invention relates to an electric bicycle that is driven and assists human driving force with the driving force of an electric motor. 2. Description of the Related Art Conventionally, such an electric bicycle is provided with a driving system using human power and a driving system using an electric motor in parallel, as shown in Japanese Patent Application Laid-Open No. 4-35887 (B62M23 / 02). 2. Description of the Related Art There is known a device in which a driving force of a driving system by human power is detected to control an output of an electric motor. [0003] In this electric bicycle, a planetary gear mechanism is interposed in the human-powered driving system to detect the driving force of the driving system by human power, that is, the rotational torque of the pedal, and the driving reaction force when the pedal is depressed is transmitted to the planet. It is a mechanism that detects in the middle of the gear mechanism. In addition to the above-described embodiment, for example, Japanese Unexamined Patent Application Publication No. Hei 4-321482 (B62M23 / 12) discloses a method for detecting a driving force of a driving system by manual power, that is, a rotational torque of a pedal. I set it between the rear wheel,
There is disclosed a configuration in which a load detecting means for detecting a driving force is provided in the middle of a drive shaft for transmitting the driving force. However, in the configuration described above, since the driving portion is located at a position distant from the rear wheel, the power loss is large before the driving force is transmitted to the rear wheel, and the pedal is required to transmit power to the rear wheel. In addition, the vertical rotation of the electric motor must be converted to the horizontal rotation of the drive shaft, and further converted to the vertical rotation to rotate the rear wheel. Further, a problem that a failure easily occurs occurs. When a load detecting means is attached to a drive shaft having a configuration described later, wiring or the like is required to send a detected signal to a control circuit for detecting a load.
There is a problem that the configuration becomes very complicated and the size becomes large. SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has an object to accurately detect a torque generated by a human power with a simple configuration and to accurately drive a motor in accordance with the torque. An object of the present invention is to provide an electric bicycle that assists driving force by human power. SUMMARY OF THE INVENTION The present invention provides a human-powered driving unit that rotates an elastic body between a pedal and a wheel by rotating the wheel by expanding and contracting the elastic body in an expanding and contracting direction by a pedaling force of the pedal. An electric drive unit that rotates the wheels by driving an electric motor, a torque detection unit that detects the amount of expansion and contraction of the elastic body,
A control unit that drives and controls the electric motor based on the detection value of the torque detection unit; and a plate-shaped casing provided on the hub of the wheel and including the electric drive unit, the torque detection unit, and the control unit. It is characterized by having. In addition, there is provided a potentiometer interposed between the elastic body and the human-powered driving member, the pressing member being rotated by the treading force of the human-powered driving portion, the value of which changes according to the displacement of the pressing member. It is characterized by the following. A rotating plate integrally formed with the pressing member and forming a gear part in a part thereof and rotating about an axle of the wheel; and rotation of the rotating plate is transmitted through the elastic body. Been
A pulley that rotates about the axle.
A the wheel rotation of over rotates is transmitted, meshing with the gear portion of the <br/> rotary plate, a small gear that rotates operate in conjunction with the rotation operation of the gear unit to the pulley characterized in that provided in provided the <br/> potentiometer. According to the present invention, when the user steps on the pedal, the pedaling force is transmitted from the pedal to the board-shaped casing and the wheels via the elastic body. When starting, when the user depresses the pedal,
When the elastic body shrinks greatly and starts moving at a constant speed, the elastic body hardly shrinks. When the vehicle is accelerated, the elastic body contracts when the pedal is depressed, and the elastic body presses the board-shaped casing, thereby rotating the wheels to travel. As described above, the elastic body interposed between the human-powered driving unit and the wheels expands and contracts in accordance with the magnitude of the human-powered torque, and the amount of the expansion and contraction is detected by the torque detection unit, so that the elastic body expands and contracts, That is, the manual torque can be detected. When the human-powered torque is detected, the control unit drives the motor with a magnitude corresponding to the torque, and when the human-powered torque increases, the assistance of the motor increases, and the vehicle travels using both the manual driving and the electric motor driving. I do. Further, the pressing member presses the elastic body in response to the movement of the human-powered driving unit, and the wheel rotates. At this time, the expansion and contraction of the elastic body is detected by the displacement of the pressing member, and the displacement is detected by a potentiometer. In order to detect the amount of displacement of the pressing member, a gear formed integrally with the pressing member is engaged with a small gear provided on the potentiometer, so that the amount of displacement of the pressing member is read by the potentiometer. Can be. Embodiments of the present invention will be described with reference to the drawings. Reference numeral 1 denotes an electric bicycle main body. The electric bicycle main body 1 is provided with an electric motor 8, which will be described later. The driving force of the electric motor 8 is changed in accordance with the magnitude of torque generated by human power, and the power generated by human power is changed by the electric motor. The vehicle is driven with the assistance of the force of No. 8. Reference numerals 2 and 3 denote a front wheel and a rear wheel provided on a main frame 4. The front wheel 2 is rotatably supported on a shaft. Is provided. The disc-shaped casing 5 includes a rotating casing 6 and a fixed casing 7, and the rotating casing 6 rotates integrally with the rear wheel 3. An electric motor 8 is incorporated in the disc-shaped casing 5 and is driven when electric driving is required, thereby rotating the rotating casing 6 together with a human-powered driving unit 10 described later. The driving portion composed of the board-shaped casing 5 is referred to as an electric driving unit 9. 10 is a step of depressing a pedal 11 so that a chain 12
And a human-powered drive unit that rotates the rear wheel 3 via the power supply. In the present invention, the chain 12 is used as the transmission member.
Alternatively, a belt, a rotating shaft, or the like may be used. Reference numeral 13 denotes a steering wheel for steering the front wheel 2. Reference numerals 14 and 15 denote left and right brake levers. The wires 16 and 17 are pulled by pulling the brake levers 14 and 15 so that the front and rear brake devices 18 and 19 are operated by the wires 16 and 17 respectively. Has become. A brake switch 20 is provided in the middle of the wires 16 and 17, so that when the brake levers 14 and 15 are operated, the power supply to the electric motor 8 is stopped. Reference numeral 21 denotes a saddle. Reference numeral 22 denotes a battery unit serving as a power source for the electric motor 8. The battery unit 22 includes a battery case 23 slidably attached to and detachable from the frame 4, and a single rechargeable battery housed in the battery case 23. It is configured. This power supply voltage is about 24 volts. Next, the disc-shaped casing 5 will be described with reference to FIG. FIG. 7 shows the disk-shaped casing 5.
7 shows a fixed casing fixed to the electric bicycle main body 1. The fixed casing 7 includes a control board 26 including a control board 24, a heat radiating plate 25, etc., an electric motor 8, Pulley 27, second pulley 28, final stage pulley 29-3
A speed reduction mechanism 30 composed of two pulleys and a transmission belt 31 connecting the speed reduction mechanisms 30 are arranged. The final stage pulley 29 of the speed reduction mechanism 30 is fixed to the rotating side casing 6. When the electric motor 8 rotates, the first to final stage pulleys are rotated by the transmission belt 31, and the speed is reduced and the final stage pulley 29 is moved together with the final stage pulley 29. The rotating casing 6 rotates. In addition, a one-way clutch is interposed in the smaller pulley of the second pulley 28 connecting the second pulley 28 and the last-stage pulley 29, and the motor 8 is turned on when a force from the pedal 11 is applied. The pedal 11 is made light so that it does not rotate. Reference numeral 32 denotes a pressing member for adjusting the tension of the transmission belt 31. Numeral 33 is an adjusting screw for adjusting the tension of the transmission belt 31. A slot is formed in a portion where the rotation shaft of the first pulley 27 is attached, and the first pulley 27 is connected to the transmission belt 31. The pulley is moved in the direction in which the pulley extends, and the pulley is fixed by the adjusting screw 33 in the moved state. Reference numeral 37 denotes a chain sprocket for transmitting the driving force from the chain 12 to the rotating casing 6. A freewheel 38 is provided between the chain sprocket 37 and the rotating casing 6. When the chain 12 rotates in the reverse direction, the driving force from the chain 12 is not transmitted to the rotating casing 6. Reference numeral 39 denotes an axle of the rear wheel 3. The structure of the last stage pulley 29 will be described in detail with reference to FIGS. Numeral 40 denotes an elastic body, that is, a spring, provided at two locations symmetrically with the axle 39 inside the final stage pulley 29,
Reference numeral 40 denotes an operation body fixed to the last-stage pulley 29, and the other side is openable and contractible. Reference numeral 41 denotes a pressure receiving member which comes into contact with the open side of the spring 40. The pressure receiving member 41 has a portion shorter and a portion longer than the diameter of the spring 40, and the short portion is fixed by entering the spring 40. ing. Reference numeral 42 denotes a turning plate which is turned by the rotation of the chain sprocket 37 and is provided around an axle 39. The turning plate 42 urges the pressure receiving member 41 of the chain sprocket 37 symmetrically with respect to the axle 39. A pressing member 43 that is pressed by rotation is provided. The rotating plate 42 is inserted concentrically inside the last stage pulley 29, and the pressing member 43 is
To rotate with the last stage pulley 29. The pressing member 43 has a curved surface because the pressing position is slightly shifted when the pressing member 41 is pressed. Further, the rotating plate 42 has a gear portion 44 formed between the two pressing members 43, and the gear portion 44 meshes with a small gear 46 that changes the value of a potentiometer 45 provided in the vicinity. ing. That is, the displacement amount of the expansion and contraction of the spring 40 caused by the stepping force of the human power can be read by the change in the value of the potentiometer 45. Reference numeral 47 denotes a rubber plate for preventing the pressing member 43 pressed by the spring 40 from being impacted. Reference numeral 48 denotes a cover for covering the spring 40. The spring 40, the rotary plate 42, and the potentiometer 45 attached to the last-stage pulley 29 described above are collectively referred to as a torque detector 49. Explaining the movement of the final stage pulley 29, when a force is applied from the manual drive unit 10, the chain sprocket 37 is pushed in the rotating direction, and the rotating plate 42 is rotated together therewith, and the rotating plate 42 is rotated. The pressing member 43 provided at the first stage presses the spring 40 via the pressure receiving member 41, and the final stage pulley 29 is rotated by the force. The final stage pulley 29 and the rotating side casing 6 are screwed
Since it is fixed by 50, the rotating side casing 6 rotates and the wheels 3 rotate. At this time, when a treading force is applied from the human power drive unit 10 for starting or accelerating, the rotating plate 42 rotates and the spring 40 contracts. Further, in the case of normal traveling, the pedaling force of the human power drive unit 10 is not applied so much, so that the spring 40 does not expand or contract very much. That is, a human-powered driving unit
The spring 40 contracts only when a pedaling force from 10 is applied. Reference numeral 51 denotes a rotating element for extracting a signal detected by the potentiometer 45, and the rotating element 51 rotates together with the final stage pulley 29. Further, the peripheral element 51 is provided with two terminals in the potentiometer 45. Numeral 52 denotes a slip ring fixed to the fixed casing 6 for transmitting a signal from the peripheral element 51 to the control section 26. The slip ring 52 rotates.
The signal is always transmitted in contact with 51. In the present invention, the peripheral element 51 and the slip ring 52 are used to send a signal detected by the rotating casing 6 to the fixed casing 7, but a rotary transformer or the like may be used. Next, another embodiment will be described. In the present embodiment, a stepping force is detected by providing a variable resistor in place of the potentiometer 45 used in the above-described embodiment. Description is omitted. In this embodiment, similarly to the above-described embodiment, when the pedaling force is applied from the pedal, the rotary plate 42 is rotated, and the spring 40 is pressed to move the final stage pulley 29, the disc-shaped casing 5, and the rear wheel 3. It has become. Then, when traveling, only when a torque of the pedaling force is applied, the spring 40 contracts according to the magnitude of the torque. Reference numeral 53 denotes an operating body provided in the middle of the spring 40 and formed of a hard iron plate or the like. The operating body 40 moves at the same time as the spring 40 expands and contracts. The operating body 53 moves in a direction in which the resistance value of the variable resistor 54 provided on the side of the spring 40 changes. In the present embodiment, the operating body 53 is formed of an iron plate or the like, but any other material may be used as long as it operates the variable resistor 54 together with the movement of the spring 40, such as a rod-shaped resin. In this embodiment, as in the above-described embodiment, the torque detector 49 is rotating during running in the rotating casing 6, so that a combination of the circumferential element 51 and the slip ring 52, a rotary transformer, and the like are used. The detected signal is sent. As described above, the spring 40 is interposed between the pedal 11 and the rear wheel 3, and the rear wheel 3 is rotated by the pedaling force of the pedal 11 via the spring 40 to detect the expansion and contraction of the spring 40. Since the detection unit 49 is incorporated in the board-like casing 5, it is possible to accurately detect human-powered torque with a simple configuration, and to assist the human-powered driving force for accurately driving the electric motor 8 according to this torque. . According to the present invention, a torque detecting section is built in a disc-shaped casing, and the torque detecting section detects the torque by the expansion and contraction of the elastic body between the pedal and the wheel. Assistance from the electric drive unit by detecting the torque of the motor, so it is possible to detect the torque in a compact configuration taking into account the entire weight of the part to be moved manually, and to detect the magnitude of the torque with an elastic body Therefore, it is possible to detect a large amount of displacement and accurately detect a subtlely changing human-powered torque. Therefore, it is possible to finely change the drive by the electric motor and to provide an accurate assist of the driving force. . Further, since the amount of displacement of expansion and contraction of the elastic body is detected by a change in the value of the potentiometer, it is possible to obtain an effect that control can be easily performed with a simple configuration. Since the small gear of the potentiometer is operated in conjunction with the gear formed on the rotary plate, the torque can be accurately detected. [0051]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view showing a configuration of a final stage pulley of an electric bicycle showing one embodiment of the present invention. FIG. 2 is a side sectional view of the same casing. FIG. 3 is a side sectional view of the plate-like casing. FIG. 4 is a plan view showing a configuration of a final pulley of an electric bicycle according to another embodiment of the present invention. FIG. 5 is a partial side sectional view of the plate-like casing. FIG. 6 is an overall perspective view of the electric bicycle according to the present invention. FIG. 7 is a configuration diagram showing an arrangement of parts of the same casing. [Description of Signs] 11 Pedal 3 Wheel (rear wheel) 40 Elastic body (spring) 10 Human power drive unit 8 Electric motor 9 Electric drive unit 49 Torque detection unit 26 Control unit 5 Disc-shaped casing 43 Pressing member 45 Potentiometer 44 Gear unit 42 Rotating plate 46 Small gear 53 Operating body 54 Variable resistor

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-6-156361 (JP, A) JP-A-57-74285 (JP, A) JP-A-6-105413 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) B62M 23/02 B60L 15/20 G01L 3/14 H02P 7/00

Claims (1)

(57) [Claim 1] An elastic body is interposed between a pedal and a wheel, and the elastic body expands and contracts in the expansion and contraction direction by the pedaling force of the pedal.
A pulley that rotates around an axle of the wheel, a human-powered drive that rotates the wheel, an electric drive that rotates the wheel by driving an electric motor, and a torque detector that detects the amount of expansion and contraction of the elastic body. A control unit that drives and controls the electric motor based on the detection value of the torque detection unit, and a plate-shaped casing provided on the hub of the wheel and including the electric drive unit, the torque detection unit, and the control unit. A potentiometer that intervenes a pressing member that rotates by the treading force of the human-powered driving unit between the elastic body and the human-powered driving unit, and that changes a value according to a displacement amount of the pressing member; a rotating plate which rotates around the axle of the wheel to form a gear part in a portion is integrally formed when the pivoting of the pivoting plate
Is transmitted through the elastic body and rotates around the axle.
And a pulley that transmits the rotation of the pulley.
The rotating wheel, wherein a small gear that meshes with a gear portion of the rotating plate and rotates in conjunction with the rotation of the gear portion is provided on a potentiometer provided on the pulley. And electric bicycle.