JPH07149280A - Bicycle having electric motor - Google Patents

Abstract

PURPOSE:To sharply reduce a charging quantity and a charging and discharging cycle by joining output of an electric motor to a rear wheel shaft to transmit driving force of an input driving system, and inputting inertial torque of the wheel shaft to the electric motor as a generator. CONSTITUTION:Foot-operated torque of a crank pedal 4 rotates a hub 9 of a rear wheel 1 by a chain, and a torque sensor 9 detects the torque. When the torque becomes a specific value or less, an electric current is carried to a generator and electric morot 3 from a battery 17, and the electric current is controlled by a controller, and it is actuated as an electric motor. The torque is joined to torque of the hub 9 through a one-way clutch 20, and rotates the rear wheel 1. When a brake is applied when inertial rotation is caused like when a bicycle descends on a sloping road, a clutch 20 engages a bevel gear 21 and the hub 9 of a rear wheel shaft 2 with each other, and the torque of the hub 9 is transmitted to an output shaft 18 by bevel gears 21 and 19, and the electric motor 3 is serving also as a generator is actuated as a generator, and charges the battery 17 with electricity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bicycle equipped with an electric motor in which a human power drive system and an electric drive system are provided in parallel, and the electric drive system has an electric motor that also serves as a generator.

[0002]

2. Description of the Related Art Conventionally, as shown in Japanese Patent Laid-Open No. 5-58379, a human power drive system and an electric drive system are provided in parallel, and the output of the electric drive system is controlled in response to a change in the drive power due to human power. Bicycles with electric motors are known. In the above-mentioned prior art, a crankshaft driven by a crank pedal forming a human power drive system, a resultant shaft rotatably held by the crankshaft and driven by the crankshaft, a vehicle body substantially orthogonal to the crankshaft, and a vehicle body. An electric motor as the electric drive system that drives the resultant shaft by a motor shaft located near the center in the width direction, and a drive torque of the crank shaft that is arranged on one side of a plane in the vehicle longitudinal direction including the motor shaft. A torque detection mechanism that detects and transmits the torque to the torque sensor, and a transmission system that is disposed on the other side of the plane and transmits the rotation of the resultant shaft to the rear wheel are provided.

Next, the operation will be described. The rotation input by human power from the pedal is transmitted from the large gear to the resultant shaft via the crankshaft, the one-way clutch, and the planetary gear type gearbox, and from the drive shaft to the rear wheel via the bevel gear mechanism. On the other hand, the driving torque due to the pedaling force of the pedal is detected by the potentiometer, and the motor current is controlled based on this torque.

[0004]

By the way, in the above-mentioned prior art, since the electric motor is operated by the battery and the battery is charged by the current of the general household, the usage time of the electric motor is limited and the charging is performed. There was a problem in that it took time.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems, and in a bicycle with an electric motor in which a human power drive system and an electric drive system are provided in parallel, a crank forming the human power drive system. The rear wheel axle to which the driving force from the pedal is transmitted is combined with the output of the electric motor as the electric drive mechanism, and the two are engaged by receiving the output from the braking member between the electric motor and the axle, The inertial rotational force is input to the electric motor as a generator when the axle rotates inertially.

[0006]

When the crank pedal is stepped on and rotated, the rotational force is transmitted to the rear wheel shaft by the chain. On the other hand, for example, when the torque sensor detects the stepping torque, and when the speed and the driving torque reach a certain value or more, an electric motor that also serves as a generator is energized in accordance with the torque from the battery to operate as an electric motor, and the rotational force is the human power. It is combined with the rotating force. When the bicycle is in inertial driving, when the brake is applied to the bicycle, the clutch operates to transmit the inertial rotation of the rear wheel shaft to the generator / motor, and the generator / motor operates as a generator, and the battery (See the block diagram of FIG. 5).

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, one embodiment of the present invention shown in the drawings will be described in detail. FIG. 1 is a schematic view of the entire bicycle. Reference numeral 1 is a rear wheel of a bicycle, and an electric motor 3 also serving as a generator is attached to a rear wheel axle 2. Reference numeral 4 is a crank pedal, and the rotational force of stepping by human power is transmitted to the rear wheel 1 by the chain 5. A torque sensor 6 is attached to the crank pedal 4.

FIG. 2 is a detailed view of the rear wheel hub portion. The rear wheel axle 2 is fixed to the frames 7 and 8 of the vehicle body. Reference numeral 9 denotes a hub rotatably supported by bearings 10 and 11 on both ends of the rear wheel axle 2, and spokes 14 of the rear wheel 1 are fixed to collars 12 and 13 in an intermediate portion. Reference numeral 15 is a drive sprocket attached to one end of the hub 9 via a one-way clutch 16, and is a chain 5 driven by the crank pedal 4.
Are engaged. The one-way clutch 16 is locked when the rotation speed of the sprocket 15 is higher than the rotation speed of the hub 9. Reference numeral 3 denotes an electric motor fixed to the frame 8 which also serves as a generator, and a bevel gear 2 in which a bevel gear 19 of an output shaft 18 is attached to a hub 9 via a one-way clutch 20.
It meshes with 1. The one-way clutch 20 is mounted so as to be in a locked state when the rotation speed of the bevel gear 21 is higher than the rotation speed of the hub 9. Reference numeral 22 is a clutch that engages the bevel gear 21 and the axle 2 with a brake lever (not shown).

The electric motor 3 also serving as a generator operates as a motor by means of a battery 17 arranged at a proper position in the vehicle body, and the battery 17 operates and charges the electric motor 3 also serving as a generator. Rotational force generated by stepping on the crank pedal 4 causes the chain 5 to rotate the hub 9 of the rear wheel 1. The torque sensor 6 detects the torque generated by the human power, and when the torque magnitude exceeds a certain value (at the time of starting or climbing a slope), the electric motor 3 also serving as a generator is energized from the battery 17, and the controller The electric current is controlled according to the magnitude of the torque to operate as an electric motor, the rotational force of which is transmitted to the hub 9 via the one-way clutch 20 and combined with the rotational force of human power to rotate the rear wheel 1 and the crank pedal 4 The stepping force to rotate is reduced.
This constant value can be arbitrarily set by a shift lever or the like. When the bicycle is braked during inertial rotation such as when going down a slope (the one-way clutch 20 is in a free state), the clutch lever 22 causes the clutch 22 to move to the bevel gear 21.
And the hub 9 of the rear wheel axle 2 are engaged (locked state), and the rotational force of the hub 9 is transmitted from the bevel gears 21 and 19 to the output shaft 18 as shown in FIG. To charge the battery 17 (see the block diagram of FIG. 4). In addition, a speed increaser may be attached to the generator in order to improve power generation efficiency.

In the above embodiment, the inertial rotation of the bicycle is regarded as the braking time for convenience, and the battery is simply charged. However, the clutch 22 is locked when the brake is applied. The control unit may be configured so that not only the time but also the driving torque and the speed are interlocked with each other so that the time sufficient for charging can be properly and efficiently detected.

Further, in the above embodiment, the electric drive system is
Although the output is controlled according to the change in the driving force due to human power, the electric drive system may be controlled independently of the driving force due to human power.

[0012]

According to the present invention, in a bicycle with an electric motor in which a human power drive system and an electric drive system are provided in parallel, a rear wheel axle to which a driving force from a crank pedal forming the human power drive system is transmitted. , The output of the electric motor as the electric drive mechanism is combined, and the output from the braking member is received between the electric motor and the axle to engage them, and when the axle is inertially rotated, the inertial torque is generated by the generator. Since the electric motor is input to the electric motor as described above, the brake is applied while the bicycle is running, and when the vehicle is coasting, this extra energy is effectively used to operate the electric motor that also serves as a generator to generate electric power and charge the battery. Therefore, it is possible to greatly reduce the amount of charge and the charging cycle in a general household, which is a great energy saving effect.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an entire bicycle to which the present invention is applied.

FIG. 2 is a front sectional view of a rear wheel hub portion of FIG.

FIG. 3 is an enlarged view of a bevel gear and a clutch portion of FIG.

FIG. 4 is a configuration block diagram of the present invention.

FIG. 5 is an operation block diagram of the present invention.

[Explanation of symbols]

 1 Rear Wheel of Bicycle 2 Rear Wheel Axle 3 Electric Motor that also serves as Generator 4 Crank Pedal 5 Chain 6 Torque Sensor 9 Hub 17 Battery 18 Output Shaft 19,21 Bevel Gear 20 One-way Clutch 22 Clutch

Claims (1)

[Claims] 1. A bicycle with an electric motor in which a human power drive system and an electric drive system are provided in parallel, wherein the electric drive mechanism is mounted on a rear wheel axle to which a driving force from a crank pedal forming the human power drive system is transmitted. As the output of the electric motor is combined, the output from the braking member is received between the electric motor and the axle to engage the two, and when the axle rotates due to inertia,
A bicycle with an electric motor, wherein the inertial torque is input to the electric motor as a generator.