JP2001030974A - Power-assisted bicycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lightweight power-assisted bicycle increased in the charging efficiency in a traveling mode to eliminate or reduce the charging work. SOLUTION: This power-assisted bicycle comprises a motor M to drive wheels, a regenerative device 31 which is connected to this motor M via a wire 30 and comprises a transistor 32 and a diode 31a to regenerate it, and a capacitor 20 with large capacity, connected to the motor M via wires 15, 21, 23, the rotation of the wheels is assisted by the drive of the motor M in a starting mode and a slope-climbing mode, and the power obtained through the regenerative braking action of the motor M is charge in a brake applying mode and in a traveling mode at high speed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor-assisted bicycle capable of driving a motor to assist the rotation of wheels when climbing a hill, and charging a capacitor by regenerative braking when traveling at high speeds.

[0002]

2. Description of the Related Art In an electric assisted bicycle, it is necessary to drive a motor to reduce the burden on the user and assist the leg force when starting or during a high load such as when climbing a hill. For this reason, a motor-assisted bicycle of a type in which a motor and a secondary battery such as a nickel-cadmium battery are mounted on a bicycle and assists the rotation of wheels at the time of high load such as climbing a slope is commercially available. Electric assisted bicycles having a regenerative device and capable of charging a secondary battery are also commercially available. However, since the charging efficiency during traveling is low, the auxiliary charging level remains at an auxiliary level.

[0003] In each of the electric assist bicycles described above, a secondary battery capable of charging a power supply is generally used. However, even if such a secondary battery is used, the charging efficiency during traveling is low, so that a charging operation from an external power source needs to be performed for a long time when the vehicle is stopped or the like. Further, an electric bicycle that automatically charges a secondary battery with electric power charged by a solar battery mounted on the bicycle during traveling has been proposed (see Japanese Patent Application Laid-Open No. 7-61391). Moreover, in the electric bicycle, when a certain traveling speed is exceeded when going down a hill, the power supply direction is switched between the motor and the secondary battery, and the battery is braked while charging the battery by the regenerative braking action of the motor. It is also included.

[0004]

However, the above-mentioned electric bicycle also uses a secondary battery, so that the charging efficiency is low. For this reason, the charging operation from an external power supply is still required when the vehicle is stopped or the like, and the weight of the secondary battery itself is a burden on the user. An object of the present invention is to solve the problems of the conventional technology described above and to provide an electric assisted bicycle that can increase or reduce the charging work by increasing the charging efficiency at the time of running and can also reduce the weight. And

[0005]

According to the present invention, in order to solve the above-mentioned problems, a large-capacity capacitor is used as power storage means mounted on a bicycle, and the power obtained by regenerative operation is charged in the capacitor. It was made inspired by. That is, the electrically assisted bicycle of the present invention includes a condenser and a motor capable of regenerative braking, and assists the rotation of the wheels by driving the motor at the time of starting and climbing a hill.
Charging the capacitor with electric power obtained by the regenerative braking operation of the motor at the time of braking and at high speed traveling,
It is characterized by the following.

[0006] An electric assist bicycle according to the present invention is characterized in that it includes a motor for driving wheels, a regenerative device connected to the motor for regenerating the motor, and a capacitor connected to the motor. It also does. According to these, when starting or climbing a slope, the motor is driven by the electric power from the capacitor to assist the rotation of the wheels to reduce the burden on the user. It is possible to charge efficiently and to eliminate or reduce charging work when the vehicle is stopped. This eliminates the need for a long-time charging operation as in the conventional secondary battery and reduces the weight, so that the weight of the entire vehicle body can be reduced and the handling can be facilitated. In addition, the above-mentioned capacitor is roughly 2
A large capacity of 0F to 50F (Farato) is used.

[0007] Further, an electric assisted bicycle in which switching between driving and regeneration of the motor is performed by a speed sensor and / or a brake switch connected to the regeneration device or a manual switch connected to the motor is also included. . According to this, the motor can be automatically switched from the drive to the regenerative operation by a speed sensor when a reference speed to be described later is exceeded, or by a brake switch interlocked with the brake during braking on a downhill. Also,
The switching can be performed by a manual switch at the discretion of the user, and the operation of the motor can be freely selected according to the situation. Note that the switching of the operation mode by the manual switch includes neutral for stopping the motor, and it is also possible to secure the safety of the user by operating the manual switch in preference to the speed sensor. is there.

In addition, a speed sensor is connected to the regenerative device, and the voltage of the regenerative device and the motor is adjusted in accordance with the rotation speed of the wheel or the speed of the bicycle detected by the sensor, or the bicycle is driven by a reference. An electric assist bicycle that controls the motor driving current via the regenerative device when the speed is lower than the speed and performs regenerative braking operation of the motor by the regenerative device when the speed exceeds the reference traveling speed. According to this, the voltage for driving the motor is increased according to the speed at the time of climbing a hill, or when the speed becomes equal to or lower than the reference speed, a current amount corresponding to the speed is supplied to the motor. Also, a current amount corresponding to the speed can be supplied from the regenerative device to the motor. Therefore, it is possible to switch to the operation of the regenerative device according to the speed at the time of downhill traveling or high-speed traveling, and to efficiently assist the propulsion leg force and charge during the regenerative braking operation according to the load state of the user. Becomes possible. When the charging of the capacitor is completed by the regenerative braking operation, the regenerative device is stopped.

Further, there is also included an electric assisted bicycle in which a brake switch linked to a brake is connected to the regenerative device, and the switch causes the motor to perform a regenerative braking operation by the regenerative device. According to this, each time the user operates the brake during downhill traveling or high-speed traveling,
The regenerative braking operation can be performed on the motor, and the capacitor can be charged efficiently with no or little load on the user.

[0010] The present invention also includes an electric assist bicycle in which a comparison computing unit is connected to the regenerative device, and the speed sensor and / or the brake switch is connected to the regenerative device via the comparator. According to this, the reference voltage corresponding to the reference speed and the voltage corresponding to the speed from the speed sensor are compared and calculated, and the motor drive or the regenerative braking operation can be appropriately performed according to the difference. Moreover, at the time of the brake operation, it is also possible to compare and calculate the voltage added by the brake switch and the reference voltage, regardless of the traveling speed, and to make the motor perform the optimal regenerative braking operation in the brake operation state.

In addition, when the charge capacity of the capacitor is reduced, a warning is displayed by a lamp or the like, and / or the power supply to the motor is stopped, or the regenerative braking operation or the solar cell or the like is performed on the capacitor. This includes electric assisted bicycles that are charged by an auxiliary power supply. According to this, when the charge capacity of the capacitor decreases, the capacitor is sequentially charged by the regenerative braking operation of the motor or the auxiliary power supply,
It is possible to eliminate or reduce the charging work when the vehicle is stopped. In addition, if the charge capacity of the capacitor falls below the level required for normal traveling, a warning can be displayed to the user with a lamp or the like, or the power supply to the motor can be stopped. Therefore, the user can be convinced to use the bicycle without assistance by the motor drive until the capacitor is charged to the above-mentioned capacity level.

[0012]

Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an electric assisted bicycle 1 of the present invention. This bicycle 1 is a post 6 having front and rear wheels 2 and 3 connected by a frame 4 and having a saddle 5 at an upper end.
Before and after, the condenser 20 and the motor M are mounted. As shown in FIG. 1, the motor M rotates a gear 9 disposed separately from the gear 8 of the pedal 7 and drives the rear wheel 3 via a dedicated chain C. The motor M is about 20
It is a DC motor of 0 to 300 W (watt).

As shown in FIG. 1, a control unit 22 containing a regenerative device, which will be described later, is disposed at the bottom of the frame 4 and a sun position above the rear wheel 3 is located at a position where the sun bed is located. A battery (photovoltaic panel / auxiliary power supply) 18 is provided. Further, the handle 10 is provided with a brake 12 linked to a brake switch described later, a manual switch 16 for switching an operation mode, and a lamp 14 for notifying that the charging capacity of the capacitor 20 has decreased. A normal power-generating light L is mounted on the front wheel 2 of the bicycle 1, and a basket B is mounted above the front wheel 2.

FIG. 2 is a schematic diagram showing an electric system of the electric assist bicycle 1. As shown in FIG. Capacitor 2 shown on the left side of FIG.
0 and the motor M shown on the right side are connected by wires 21, 23 and 15 via a manual switch 16. The manual switch 16 can select any one of the neutral terminal 17, the motor drive terminal 16a, and the regeneration terminal 16b. The drive terminal 16a is connected to the capacitor 20 via the wiring 23, and the voltage converter 25 and the diode 2
6 are arranged. This converter 25 comprises a capacitor 20
The constant voltage for driving the motor M is set to the constant voltage for driving the motor M, and the backflow is prevented by the diode 26. The regeneration terminal 16b is connected to the capacitor 20 via the wiring 21, and a diode 24 is arranged on the way. The diode 24 rectifies the regenerated current supplied from the motor M during the regenerative braking operation, and
Charge. The manual switch 16 is normally connected to the regenerative device 3 described later, except when the neutral switch is selected.
It is set so as to be automatically linked in accordance with the operation of No. 1.

As shown on the left side of FIG.
Has one end connected to a ground 27, and an auxiliary power source such as a solar cell 18, for example, is connected to the pair of electrodes, as shown by a dashed line in FIG. Thus, regardless of the running state of the bicycle 1, it is possible to sequentially charge the capacitor 20 with the electric power photo-generated by the solar cell 18 in fine weather. As the capacitor 20, an electric double layer type having a large capacity of about 20F to 50F (farat) is used. As shown in FIG. 2, a circuit 26 having a resistor 28, a lamp 14, and a dry cell 29 is further connected in parallel to each electrode of the capacitor 20. This circuit 26 turns on the lamp 14 by the dry battery 29 when the charged capacity of the capacitor 20 falls below the capacity level necessary for driving the motor M, and warns the user on the steering wheel 10 of such a state. Is what you do. The resistor 28 is connected to the capacitor 20 in normal times.
From the power supply to the circuit 26.

As shown on the right side of FIG. 2, the motor M is connected to a regenerative device 31 in the control unit 22 via a wiring 30. The regenerative device 31 includes a diode 3 for supplying a regenerative current.
1a and the transistor 32. That is, the current sent from the capacitor 20 to the wiring 30 by driving the motor M flows as shown by the arrow and flows from the wiring 32c to the ground 33 when a positive voltage is applied to the base 32b of the transistor 32. On the other hand, the base 32 of the transistor 32
When a negative voltage is applied to the transistor b and the transistor 32 is in an OFF state, a regenerative current is supplied from the diode 31a to the motor M via the wirings 31b and 30 to cause the motor M to perform a regenerative braking operation. At this time, the switch 16 is switched from the drive terminal 16a to the regeneration terminal 16b via, for example, a relay.

Further, as shown in FIG. 2, the transistor 32 is connected from its base 32b to a comparator 34 via a wiring 32a. The arithmetic unit 34 performs a comparison operation between the positive (+) side input voltage V ₊ and the negative (−) input voltage V ₋ to obtain a difference between the two: K (V ₊
−V ₋ ) to the transistor 32.
A speed sensor 36 is connected via a wiring 35 to a negative (−) side input portion of the comparison calculator 34. This sensor 3
6 comprises a rotary encoder 37 and an FV converter 38, for example. Based on the rotation speeds of the wheels 2 and 3 of the bicycle 1 detected by the encoder 37, the converter 38 converts the voltage into a voltage proportional to the traveling speed of the bicycle 1, and converts this speed proportional voltage to a negative voltage of the arithmetic unit 34. Supply to the (-) side.

If the speed of the bicycle 1 is lower than the reference speed, a low current is output from the sensor 36 to the negative (-) side of the comparator 34, and the motor M Is transmitted toward the earth 33 to assist the rotation of the rear wheel 3 by driving the motor M. On the other hand, when the bicycle 1 exceeds the reference speed, a high current is output to the negative (-) side of the comparison operator 34, and the base 32b of the transistor 32 is set to a negative voltage, so that the transistor 3
2 is turned off, and a regenerative current is supplied from the diode 31a to the motor M.

Further, as shown in FIG.
Is connected to the positive (+) side input section of
The secondary battery 40 is connected, and the other end of the battery 40 is connected to the ground 4.
1a. The battery 40 supplies a reference voltage matched to the reference speed of the bicycle 1 to a positive (+) side input unit of the arithmetic unit 34. Further, a brake switch 42 that opens and closes in conjunction with the operation of the brake 12 is provided between the wiring 41 of the positive (+) side input section and the wiring 35 of the negative (−) side input section of the comparator 34, A circuit 43 having a battery 44 forcibly operating the switch 42 is connected.

For example, when the brake 12 is applied on a downhill and the brake switch 42 is closed, the primary battery 40 is also connected to the wiring 35 via the circuit 43.
In the comparator 34, the negative (−) side is larger than the positive (+) side,
The base 32b of the transistor 32 has a negative voltage. As a result, the transistor 32 is turned off, so that the drive current from the motor M does not flow and the diode 3
A regeneration current is supplied to the motor M from 1a. For this reason, the motor M performs a regenerative braking operation, and the electric power generated thereby can charge the capacitor 20.

Here, the driving state of the battery-assisted bicycle 1 will be described assuming that its reference speed is, for example, 15 km / h. It is assumed that the capacitor 20 has been charged in advance with power of a required capacity or more. When the bicycle 1 is started, its speed is detected by the speed sensor 36 as shown in FIG. This speed is the reference speed (15km / h)
In the following, since a current flows through the transistor 32 of the regenerative device 31, a driving current flows from the capacitor 20 to the motor M via the wirings 23 and 15, and a torque generated by the motor M is generated together with a leg force of the user pedaling the pedal 7. The power is transmitted to the rear wheel 3. Therefore, it is possible to assist the user immediately after the start. It should be noted that even when the bicycle 1 does not reach the reference speed other than immediately after the start, for example, when the user receives a headwind and the speed decreases, the driving of the motor M is similarly assisted.

When the bicycle 1 is running at a constant speed equal to or lower than the reference speed, the motor driving current is controlled to be substantially constant by the speed sensor 36 and the transistor 32 of the regenerative device 31. Further, when the bicycle 1 is running at a speed exceeding the reference speed (15 km / h) during downhill running or high-speed running, the speed sensor 36 shown in FIG. 2 stops the transistor 32 of the regenerative device 31. At the same time, the current for regeneration from the diode 31a of the regeneration device 31
Sent to At this time, a regenerative braking operation is performed in the motor M, and the induced electromotive force is charged in the capacitor 20 through the wiring 21. That is, at the time of downhill traveling or high-speed traveling, the driving of the rear wheel 3 is sufficient only by the user's pedaling force, and the bicycle 1 can be easily traveled. Then, the capacitor 20 is charged. After the charging of the capacitor 20 is completed, the regenerative device 31
(32) is stopped.

By the way, when the brake 12 is applied during traveling downhill, the bicycle 1 temporarily falls below the reference speed. At this time, if the drive current is supplied to the motor M by the speed sensor 36 as described above, the speed is rather increased, which is dangerous. Therefore, when the brake 12 is applied, FIG.
As described above, the brake switch 42 is closed to stop the transistor 32 of the regenerative device 31, and the regenerative current is supplied from the diode 31a to the motor M to perform the regenerative braking operation. Regardless of the traveling speed, the driving assistance of the rear wheel 3 is not required even when the brake 12 is applied for the sake of safety by the user.
The regenerative braking operation is performed as described above.

Further, with an auxiliary power source such as the solar cell 18 illustrated in FIG. 2, the photovoltaic power is generated at any time irrespective of the running state or the stopped state of the bicycle 1, and the electric power is charged in the capacitor 20. You. That is, in the electric assisted bicycle 1 as described above, the regenerative braking operation of the motor M is performed when the vehicle is running beyond the reference speed or the brake 12 is operated, and the capacitor 20 is charged. 20 is charged with electric power. Therefore, in a normal use state, the capacitor 20 is charged with electric power at a level necessary for driving the motor M, so that the battery is charged when the vehicle stops, like a conventional secondary battery such as a nickel-cadmium battery. Work can be eliminated or reduced. still,
If the charged amount of the capacitor 20 is insufficient, the lamp 14 in the circuit 26 lights up and a warning is displayed. At this time, the user takes the bicycle 1, for example, from indoors to outdoors,
The capacitor 20 is charged by the solar cell 18.

The manual switch 16 shown in FIG.
If the neutral (17) is selected, the assistance by the motor M is cut off, and the vehicle can be used even when the user wants to run with only his / her own leg strength. Of course, the operation of the regenerative device 31 can be visually displayed appropriately near the handle 10 and the user can manually switch the switch 16 to the motor drive (16a) or the regenerative braking operation (16b) accordingly. is there. The present invention is not limited to the embodiments described above. For example, the diode 24 in FIG.
26, 31a, the transistor 32, the comparison calculator 34, the converters 25, 38, and the resistor 28 of the circuit 26 can be replaced by elements having the same functions as those described above, and these can be replaced on a single wiring board or the like. Can be formed in the printed circuit provided in the control section 22 and disposed in the control section 22.

As shown in FIG. 1, the motor M is mounted on the post 6 and indirectly drives the rear wheel 3 via a chain C (assist). In this manner, the bicycle 1a may be a direct drive type in which the motor M is mounted near the center of the rear wheel 3 and the torque is transmitted to the rear wheel 3 directly. In this case, the control unit 22 can be arranged behind the post 6, which makes it easier to get on and off. Further, as shown in FIG. 3 (B), the size of the panel of the solar cell 18 is increased, and
0, a pair of curved frames 19 may be arranged, and the battery-assisted bicycle 1b in which the solar cell 18 is mounted horizontally above the saddle 5 may be used. This allows the solar cell 18 to charge the capacitor 20 more efficiently, and can be used as a roof for both rain and sun protection for the user. The auxiliary power supply in the present invention is not limited to the solar cell 18, but may be a generator of a type in which the rotor is rotated by the wheels 2 and 3, a wind generator that can be mounted on the bicycle 1, or a combination thereof. It is also possible.

[0027]

According to the electric assisted bicycle of the present invention described above, at the time of starting or climbing a slope, the motor is driven by the electric power from the condenser to assist the rotation of the wheels to reduce the burden on the user, and The electric power can be efficiently charged to the capacitor by a regenerative braking operation at the time of a brake operation or high-speed running. Therefore, the conventional charging operation for the secondary battery for a long time is not required, and the weight of the capacitor can be reduced, so that the entire vehicle body can be reduced in weight and the user can easily handle it. Further, according to the electric assisted bicycle of the present invention, when the speed is equal to or lower than the reference speed, a current amount corresponding to the speed is supplied to the motor to assist the driving of the wheels. The amount can be supplied to the motor from the regenerative device, and the obtained power can be charged to the capacitor. Further, claim 7
According to the electric assisted bicycle, the capacitor is sequentially charged by the auxiliary power supply, eliminating or reducing the charging work at the time of stopping, and when the charging capacity of the capacitor falls below the required level, it is displayed to the user with a lamp etc. You can also.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing the appearance of an electric assist bicycle according to the present invention.

FIG. 2 is a schematic diagram showing an electric system and its circuit in the electric assist bicycle of FIG. 1;

FIGS. 3A and 3B are schematic side views showing the appearance of a battery-assisted bicycle of a different form.

[Explanation of symbols]

 1, 1a, 1b Electric assist bicycle 3 Rear wheel (wheel) 14 Lamp 16 Manual switch 18 Solar cell (auxiliary power supply) 20 ……………………………………………………………………………………………………………………………………………… Comparison calculator 36 ……………………… Speed sensor 42 …………… Brake switch M ……………………………………………………

Claims (7)

[Claims] 1. A motor having a condenser and a motor capable of regenerative braking operation, assisting the rotation of wheels by driving the motor at the time of starting and climbing a hill, and being obtained by the regenerative braking operation of the motor at the time of braking operation and at high speed running. Charging the power to the capacitor,
A battery-assisted bicycle characterized in that: 2. A motor-assisted bicycle comprising: a motor for driving wheels; a regenerative device connected to the motor for regenerating the motor; and a capacitor connected to the motor. 3. The method according to claim 1, wherein switching between driving and regeneration of the motor is performed by a speed sensor and / or a brake switch connected to the regenerative device or a manual switch connected to the motor. Item 3. The electric assisted bicycle according to item 2. 4. A speed sensor is connected to the regenerative device, and the voltage of the regenerative device and the motor is adjusted according to the rotation speed of the wheel or the speed of the bicycle detected by the sensor, or the bicycle runs as a reference. 4. A motor driving current is controlled via the regenerative device when the speed is lower than the speed, and a regenerative braking operation of the motor is performed by the regenerative device when the speed exceeds a reference traveling speed. The electric assisted bicycle according to 1. 5. The electric assist according to claim 3, wherein a brake switch linked to a brake is connected to the regenerative device, and the switch causes the motor to perform a regenerative braking operation by the regenerative device. bicycle. 6. The regenerative device according to claim 3, wherein a comparative computing unit is connected to the regenerative device, and the speed sensor and / or the brake switch is connected to the regenerative device via the comparator. Electric assisted bicycle. 7. When the charge capacity of the capacitor decreases,
The warning is displayed by a lamp or the like, and / or the power supply to the motor is stopped, or the capacitor is charged by the regenerative braking operation or an auxiliary power supply such as a solar cell. 6. The electric assisted bicycle according to any one of 6.