JP2000108980A - Motor assisted bicycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor assisted bicycle provided with cushioning function for rapid escape by increasing a motor driving assist ratio according to a rough road such as a rugged road. SOLUTION: When control is started (S41), the detected output V of a sensor is compared with a riding detection level V1 (S42), and motor driving assist is turned off (S45) in the case of not V>V1. In the case of V>V1 (S42), it is so judged that a person is riding a bicycle. In the case of not ΔV = (maximum value Vmax - minimum value Vmin) specified value V2 (S43), it is so judged that a road is not such a rough road as to increase an assist ratio, and a normal mode is selected (S46). In the case of ΔV>V2 (S43), the road is judged as a rough road, and a power up mode is selected to set the assist ratio A to the value increased from the specified value A0 by the α-value corresponding to ΔV, that is, the assist ratio A = specified value A0+α (S44).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric assist bicycle having a cushion function in a frame portion of a vehicle body and assisting a human driving force by a motor driving force.

[0002]

2. Description of the Related Art Recently, an electric vehicle has attracted attention, and has both a human-powered driving unit and a motor-driven electric driving unit, and drives a motor in accordance with the magnitude of the human-powered driving force. Assisted bicycles, which assist with the driving force of a motor, are gaining in popularity. On the other hand, among ordinary bicycles, cushion bicycles having a cushion function in a frame portion of a vehicle body and absorbing a shock of a rough road such as a bumpy road to improve a riding comfort have appeared. However, an electric assist bicycle in which the electric assist function is applied to a cushion bicycle has not been put to practical use.

[0003]

In an electric assist bicycle in which the electric assist function is applied to a cushion bicycle, the impact of a rough road such as an uneven road is absorbed by a cushion provided on a frame portion of a vehicle body. In an electric bicycle, the assist ratio is usually constant, and if the assist ratio remains unchanged, the vehicle cannot travel quickly on a rough road and causes unstable driving.

Accordingly, the present invention appropriately adjusts the assist ratio of the electric driving force in response to a rough road such as a bumpy road or a flat road. It is an object of the present invention to provide an electrically assisted bicycle having a cushion function in a frame portion of a vehicle body, which is capable of performing the operation.

[0005]

In order to achieve the above object, an electric assist bicycle according to claim 1 of the present invention comprises:
In an electric assist bicycle provided on a frame of a vehicle body and provided with a cushion portion for absorbing vibration of the vehicle body, when a detection value of a sensor provided on the cushion portion has a predetermined change width, the assist ratio of the electric driving force is reduced. It was configured to add only a predetermined value.

According to a second aspect of the present invention, there is provided an electric assist bicycle provided on a frame of a vehicle body and provided with a cushion portion for absorbing vibration of the vehicle body. The configuration is such that the assist ratio of the electric driving force is increased by a predetermined value according to the change width.

According to a third aspect of the present invention, there is provided an electric assist bicycle provided on a frame of a vehicle body and provided with a cushion portion for absorbing vibration of the vehicle body. The assist ratio of the electric driving force is increased by a predetermined value according to the change width, and the assist ratio is configured to increase as the change width increases.

According to a fourth aspect of the present invention, there is provided an electric assist bicycle provided on a frame of a vehicle body and having a cushion portion for absorbing vibration of the vehicle body, wherein a sensor for detecting an operation of the cushion portion is provided with a pressure sensor. The sensor is configured to increase the assist ratio of the electric driving force by a predetermined value when the detected value has a predetermined change width.

Thus, the electric assist bicycle of the present invention having a cushion function in the frame portion of the vehicle body increases the overall driving force by increasing the assist ratio of the electric driving force on rough roads or other rough roads. And you can escape there quickly.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described based on an embodiment with reference to the drawings. Here, an example of an electric assist bicycle of a type in which the rear wheel is directly rotated by an electric motor provided by the present applicant, that is, a so-called rear wheel direct drive type electric bicycle will be described with reference to the drawings.

FIG. 1 is an overall perspective view of an electric assist bicycle of a rear wheel direct drive type, in which 1 is an electric bicycle main body. The electric bicycle main body 1 is provided with a drive unit 12 including a motor to be described later, and changes the drive force of the drive unit 12 according to the magnitude of the torque by human power.
The vehicle is driven by assisting human power with the power of a motor.

The front wheel 2 is mounted on the frame of the electric bicycle body 1.
The rear wheel 3, the steering wheel 4 and the saddle 11 are attached, and the front wheel 2 is steered by the steering wheel 4. A drive unit 12 that is covered by a disk-shaped casing is provided on the rotation shaft of the rear wheel 3. Drive unit 1
The motor 2 is built in, and is driven when electric driving is required, and rotates the rear wheel 3 together with a human-powered driving unit described later. A lamp 16 having a main lamp for illumination and an auxiliary lamp is fixed to the frame of the handle 4.

The frame of the electric bicycle body 1 includes a front frame 5, a rear frame 6, a vertical frame 7, and a seat tube 8.
And one end thereof is pivotally connected by a pivot portion 9. A cushion 10 is connected between the front frame 5 and the vertical frame 7 by a joint.

The installation state of the cushion 10 will be described with reference to FIG. The cushion unit 10 houses a cylinder 21, a spring 22, and a sensor 23 for detecting the operation of the cushion unit, for example, a pressure sensor in a cylinder cylinder 20.
To the front frame 5 and to the rear frame 7 by the joint 25, respectively. The sensor 23 is not limited to a pressure sensor, but may be any other sensor that detects the operation of the cushion portion.

The front frame 5 is provided with a battery unit 15 for powering a motor and a lamp. The battery section 15 is composed of a battery case slidably attached to the front frame 5 and a single rechargeable battery housed in the battery case. The power supply voltage is approximately 24 volts. In addition, the battery part 15 can also be provided in a place other than a frame.

The manual drive unit includes a pedal 13 and a chain 14
When the user steps on the pedal 13, the rear wheel 3 is rotated via the chain 14. In this example, the chain 14 is a transmission member of human power. However, the invention is not limited thereto, and a chain, a belt, a rotating shaft, or the like may be used instead.

Brake levers (not shown) are attached to both left and right ends of a steering wheel 4 for steering the front wheels 2, and a brake device (not shown) is provided for the front wheels 2 and the rear wheels 3. Pulling the lever pulls the wire,
These wires operate the front and rear brake devices, respectively. In addition, a brake switch is provided in the middle of the wire, so that when the brake lever is operated, the power supply to the motor is stopped.

As described above, in the electric assist bicycle in which the electric assist function is applied to the cushion bicycle, as a function of the cushion bicycle, the impact of a rough road such as an uneven road is affected by the cushion portion 10 provided on the frame portion of the vehicle body.
In a rear wheel gap where a rough road or the like hits the rear wheel 3, shock is absorbed by the saddle 11, and in a front wheel gap, the front and rear wheels absorb shock.

Next, the relationship between the detection output of the sensor 23 of the cushion section 10 and the riding and driving states of the electrically assisted bicycle will be described with reference to FIG. Here, the sensor 23 will be described as a pressure sensor. In FIG. 3, when a person starts riding at time t1, the pressure sensor shows a state where the level slightly exceeds the riding detection level V1 from the stationary level V0. Then, at time t2, when a rough road such as a bumpy road is encountered, the pressure sensor detects rattling of the vehicle body and the detection level of the pressure sensor repeats oscillation.

Next, at time t3, when the vehicle escapes from a rough road such as a bumpy road, the detection level of the pressure sensor is restored to a normal riding level. Then, a change width ΔV of (maximum value Vmax−minimum value Vmin) during one cycle of the change of the pressure sensor output V can be obtained.

As a function of the cushion bicycle, the impact of a rough road such as a bumpy road is absorbed by the cushion portion 10 provided on the frame portion of the vehicle body. In the present invention, when the variation width ΔV of the pressure sensor output V becomes equal to or more than the predetermined value v2, for example, the assist ratio is increased (plus) by α to increase the assist ratio on a rough road. Is to run quickly and get out of unstable driving state quickly.

The value of α for increasing the assist ratio is shown in FIG.
As shown in the graph, when the change width ΔV of (maximum value Vmax−minimum value Vmin) in one cycle of the change of the pressure sensor output V is equal to or more than the predetermined value v2, the assist ratio is increased to α = 1 up to α = 1.
Only increase (plus).

Next, the control for increasing the assist ratio on the above-mentioned rough road will be described with reference to the flow chart of FIG. Step 41
Is started, the detection output V of the sensor 23 of the cushion portion 10 is compared with the boarding detection level V1 in step 42, and it is determined whether or not V> the boarding detection level V1. If V> riding detection level V1 is not satisfied, it is determined that the bicycle is stopped, and in step 45 the electric assist is turned off to save power.

If V is greater than the boarding detection level V1 in step 42, it is determined that a person is riding on the bicycle, and in the next step 43, ΔV = (maximum value Vmax−minimum value V
min)> predetermined value V2. If not ΔV> predetermined value V2, it is determined that the road is not bad enough to increase the assist ratio, and in step 46, the normal mode is selected in the same manner as when driving on a flat road, and the assist ratio A is set to a flat road. Is set to a predetermined assist ratio A0.

If ΔV> predetermined value V2 in step 43, the assist ratio is increased and it is determined that it is a bad road that requires quick exit. In step 44, the power-up mode is selected, and the assist ratio A is determined. It is assumed that the value increased from the value A0 by the value of α corresponding to ΔV in FIG. 5, that is, the assist ratio A = the predetermined value A0 + α. In this way, the vehicle runs quickly on a rough road and attempts to escape quickly from an unstable driving state. Hereinafter, the control operation is repeated.

The electric power assisted bicycle according to the present invention is designed with lighting means as one of the measures against bad roads. Next, it will be briefly described. In night driving on rough roads, the steering wheel is taken and the lamp shakes together, so the lighting is not fixed and the amount of light tends to be insufficient. Accordingly, in the present invention, an auxiliary lamp is provided separately from the main lamp, and when the unevenness of the rough road becomes large and the fluctuation width of the cushion portion exceeds a predetermined value, current is also supplied to the auxiliary lamp to assist the main lamp. An attempt is made to increase the amount of light by adding a lamp.

This will be described with reference to the schematic diagram of the electric circuit of the electric assist bicycle shown in FIG. Motor drive circuit is battery 1
5, a torque detector 61, a microcomputer 6
2, constant voltage circuit 63, motor drive circuit 64, motor 6
5. It is composed of a drive control element 66. Here, the operation is omitted. The lighting control system is also the battery 1
5 is supplied with power via a constant voltage circuit 68, and comprises an auxiliary lamp drive circuit 67, a main lamp 16, an auxiliary lamp 26, and a switching element 69.

When a bicycle is driven on a rough road while driving at night, fluctuations in the cushion portion are detected by the pressure sensor 23 and supplied to the microcomputer 62. The microcomputer 62 changes the cushion width ΔV = (maximum value). Vmax-minimum value Vmin)
When detecting that the predetermined value V2 is reached, a control signal is supplied to the auxiliary lamp drive circuit 67.

The auxiliary lamp drive circuit 67 controls the conduction of the switching element 69 to supply a current to the auxiliary lamp 26 via the constant voltage circuit 68, so that the main lamp 16 already lit is additionally lit. As a result, the relative light amount increases, and the instability of illumination on a rough road can be covered.

[0032]

As described above, the electric assist bicycle of the present invention provided with a cushion function in the frame portion of the vehicle body appropriately adjusts the assist ratio of the electric driving force according to a rough road such as a bumpy road or a flat road. By adjusting the speed, the vehicle can run quickly on a rough road and quickly escape from an unstable driving state, and the battery consumption can be adjusted according to the road surface condition to save power.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of an electric assist bicycle.

FIG. 2 is an enlarged view of a cushion portion.

FIG. 3 is an output waveform diagram of a pressure sensor.

FIG. 4 is a control flow for increasing the assist ratio.

FIG. 5 is a diagram illustrating a relationship between a variation width ΔV of a pressure sensor output and an increase value α of an assist ratio.

FIG. 6 is a schematic diagram of an electric circuit of the electric assist bicycle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric bicycle main body 2 Front wheel 3 Rear wheel 4 Handle 5 Front frame 6 Rear frame 7 Vertical frame 8 Seat tube 9 Pivot part 10 Cushion part 11 Saddle 12 Electric drive part 13 Pedal 14 Chain 15 Battery part 16, 26 Lamp 20 Cylinder cylinder 21 Cylinder 22 Spring 23 Sensor 24, 25 Joint 61 Torque detector 62 Microcomputer 63, 68 Constant voltage circuit 64 Motor drive circuit 65 Motor 66 Drive control element 67 Auxiliary lamp drive circuit 69 Switching element

Continued on the front page (72) Inventor Masanori Kamei 2-5-5-1 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor Hiroaki Sagara 2-5-2-5 Keihanhondori, Moriguchi-shi, Osaka Inside Sanyo Electric Co., Ltd. (72) Toshihiro Matsumoto 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Prefecture Inside Sanyo Electric Co., Ltd. (72) Yoshihiko Maeda 2-5-2 Keihanhondori, Moriguchi-shi, Osaka No. 5 F term in Sanyo Electric Co., Ltd. (reference) 3D014 DD02 DD03 DE05 DE22

Claims (4)

[Claims] 1. An electric assist bicycle provided on a frame of a vehicle body and provided with a cushion portion for absorbing vibration of the vehicle body, when the operation of the cushion portion has a predetermined change width, the assist ratio of the electric driving force is reduced. An electric assist bicycle characterized by adding a predetermined value. 2. The electric assist bicycle according to claim 1, wherein a sensor is provided on the cushion portion, and an assist ratio of the electric driving force to be added is changed according to a variation width of the detected value. 3. The electric assist bicycle according to claim 2, wherein the assist ratio increases as the change width increases. 4. The electric assist bicycle according to claim 1, wherein the sensor for detecting an operation of the cushion portion is a pressure sensor.