JPH1059262A - Output control method of motor for motor-assisted bicycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a motor in a small size so as to realize the light weight and the low cost of an assist type electric bicycle, by controlling the response speed of the output of the motor driving according to the torque. SOLUTION: An assist torque setting unit 31 outputs an assist torque instruction signal required to an assist motor 8. A comparator 32 compares the assist torque instruction and the torque of the motor 8, the deflection is proportioned and intagrated through a proportion circuit 33 and an integrator 34, the result is input to a pulse width modulator (PWM) control device 35, it is controlled at a specific duty, and a driving current according to the duty is fed to the motor 8, so as to output an assist torque to satisfy the relation of a human torque and an assist ratio. A proportional constant setting unit 36 decides the constant of the proportional circuit 33 corresponding to the motor torque signal, to reduce the response delay on a plain running road, to increase the response delay at the running on a hill, and to increase the response delay gradually during the time from the plain running road to the running on a hill road, so as to control the setting.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an output control method for an electric bicycle motor suitable for use in an electric bicycle, which is also called an assist bicycle, in which human driving force is assisted 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. Electric bicycles that assist with the driving force of a motor are gaining in popularity.

Here, an electric bicycle of the type in which the rear wheel is directly rotated by an electric motor provided by the present applicant, a so-called electric bicycle,
An example of a 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 bicycle of a rear-wheel direct drive type, in which 1 is an electric bicycle main body.
The electric bicycle body 1 is provided with a motor 8 to be described later. The driving force of the motor 8 is changed in accordance with the magnitude of the torque by human power, and the electric power is driven by assisting the power of the motor 8 by the power of the motor 8. Has become.

[0005] A front wheel 2, a rear wheel 3, a handle 13 and a saddle 21 are mounted on a frame 4 of the electric bicycle main body 1, and the front wheel 2 is steered by the handle 13. A disk-shaped casing 5 is provided on the rotation shaft of the rear wheel 3.
Is provided.

The disc-shaped casing 5 has a rotating casing 6 and a fixed casing 7 fixed to the electric bicycle main body 1. The rotating casing 6 rotates integrally with the rear wheel 3. I have.

A motor 8 is built in the board-shaped casing 5 and is driven when electric driving is required to rotate the rotating casing 6 together with a human-powered driving unit 10 described later. The driving portion including the disc-shaped casing 5 is the electric driving unit 9.

The human-powered drive unit 10 includes a pedal 11 and a chain 12, and when the user steps on the pedal 11,
The rear wheel 3 is rotated via the chain 12. In this example, the chain 12 is a transmission member of human power. However, the invention is not limited thereto, and a chain, a rotating shaft, or the like may be used instead of the chain 12.

Brake levers 14 and 15 are attached to both left and right ends of a steering wheel 13 for steering the front wheels 2, and brake devices 18 and 19 are provided for the front wheels 2 and the rear wheels 3, respectively. And brake devices 18, 19
Are connected by wires 16 and 17.

The wires 16, 17 are pulled by pulling the brake levers 14, 15, and the wires 16, 17 are pulled.
The front and rear brake devices 18 and 19 are respectively operated by 17. Further, a brake switch 20 is provided in the middle of the wires 16 and 17, and the mechanism is such that energization of the motor 8 is stopped when the brake levers 14 and 15 are operated.

A battery section 22 serving as a power supply for the motor 8 is mounted on the frame 4 on the rear wheel 3. The battery section 22 includes a battery case 23 slidably attached to the frame 4 and a single-type rechargeable battery housed in the battery case 23. The power supply voltage is approximately 24 volts. Note that the battery case 23 may be provided in another place of the frame 4.

Next, the disc-shaped casing 5 will be described with reference to FIGS. FIG. 2 is a front view showing the configuration of the disc-shaped casing 5 shown in FIG. 1, and in the drawing, reference numeral 7 denotes a fixed casing fixed to the electric bicycle main body.

The fixed casing 7 includes a control board (not shown) composed of a control board and a heat sink, a motor 8, a first pulley for transmitting the output of an output shaft 24 of the motor 8, and a pulley set 25 of a second pulley. A speed reduction mechanism 26 composed of three pulley groups of the last stage pulley 28, and a transmission belt 27 connecting between the pulleys of the speed reduction mechanism 26 and the last stage pulley 28 are arranged.

The last-stage pulley 28 is fixed to the rotating casing 6. When the motor 8 rotates, the portion from the output shaft 24 of the motor 8 to the last-stage pulley 28 is rotated by the transmission belt 27, and is decelerated to a final stage. The rotation side casing 6 rotates together with the pulley 28.

The second pulley 28 connected to the last pulley 28
A one-way clutch (not shown) is interposed in the smaller pulley so that the motor 8 is not turned when a force from the pedal is applied, that is, the pedal is light. 29 is a rear wheel axle.

FIG. 3 shows a motor 8 in the disk-shaped casing 5.
It is a front view which shows the arrangement state of a stator, 30 is a stator, 40
Is a magnet.

In such an electric bicycle, the ratio of the motor driving force to the human power, that is, the so-called assist ratio, is changed to the speed 1 by the notification from the National Police Agency, as shown in the traveling conceptual diagram of FIG.
1 up to 5 km / h, 15 km / h or more and 24 km / h
h, the ratio is changed so as to gradually decrease linearly, and 2
At 4 km / h or more, the driving by the motor driving force must be stopped and the driving force must be kept within this range.

For this reason, a microcomputer which is a control circuit for calculating how much the motor driving force is usually provided, the torque by the manual driving force and the running speed are input, and the assist ratio is determined by the table data held by the microcomputer. Is changing.

For example, assuming that a torque is applied to a human-powered drive of 100 kg · cm, if the running speed is 10 km / h, the torque by the motor driving force is set to 100 kg · cm or less, and if the running speed is 20 km / h, the assist is applied. The ratio must be reduced to 0.44, so 44kg
The output of the motor driving force of cm is calculated and output in the microcomputer.

[0020]

In the assist type electric bicycle, the assist motor torque is output in the same cycle and substantially in the same phase with respect to the human power torque in order to make the riding comfort of the rider smooth as if by stepping. There is a need. The torque relationship is shown by a solid line in FIG. 5 and a dashed line in FIG. In these cases, the response delay of the motor torque to the manual torque is 0.1 sec.

However, paying attention to the case of the slope shown in FIG. 6, a large motor torque is required in accordance with the human-powered torque, and the peak of the torque is increased. Therefore, a large motor for covering a large output is required. I understand. On the other hand, in the assist type electric bicycle, it is required to use the battery efficiently and to reduce the size of the motor to reduce the weight as much as possible.

Therefore, the present invention maintains the riding comfort of a bicycle on a flat runway and does not completely synchronize with manpower torque on a slope, but returns to assist motor torque when there is no manpower torque. It is an object of the present invention to provide an output control method for an electric bicycle motor that enables smooth and smooth running and enables downsizing of an assist motor.

[0023]

According to a first aspect of the present invention, there is provided an output control system for an electric bicycle motor, comprising: an assist torque setting device for detecting human torque; and a drive control of the motor based on an output from the assist torque setting device. A motor control device for controlling the response speed of the motor drive output to the human-powered torque according to the magnitude of the human-powered torque.

According to a second aspect of the present invention, there is provided an output control system for an electric bicycle motor, comprising: an assist torque setting device for detecting a human-powered torque; and a motor control device for driving and controlling the motor based on an output from the assist torque setting device. A response speed of the motor drive output with respect to the human-powered torque is controlled in accordance with the magnitude of the drive signal of the motor.

According to a third aspect of the present invention, there is provided an output control method for an electric bicycle motor, comprising: an assist torque setting device for detecting a human-powered torque; and a motor control device for driving and controlling the motor based on an output from the assist torque setting device. A response speed of the motor drive output with respect to the manual torque is controlled in accordance with the magnitude of the motor torque.

According to a fourth aspect of the present invention, there is provided an output control method for an electric bicycle motor, comprising: an assist torque setting device for detecting a human-powered torque; and a motor control device for driving and controlling the motor based on an output from the assist torque setting device. When the manpower torque or the drive signal of the motor or the motor torque is small, the response speed of the motor drive output to the manpower torque is controlled to be fast, and when it is large, the response speed of the motor drive output to the manpower torque is controlled to be slow. It is characterized by.

Thus, on a flat traveling road, it is possible to obtain a riding comfort of a bicycle with good tracking characteristics in which the human torque and the motor torque are synchronized while satisfying the condition as the assist torque of the motor. Further, when traveling on a slope, the peak value of the torque is kept low, the output of the assist motor is reduced, and the motor can be downsized, so that the weight and cost of the assist type electric bicycle can be reduced.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described based on an embodiment with reference to the drawings. FIG. 7 shows the relationship between the motor torque and the manpower torque when traveling on a slope (the manpower torque is indicated by a solid line and the motor torque is indicated by a broken line). This is the case of 4 sec.

As described above, by delaying the response speed of the motor torque to the manual torque, the condition of the assist torque of the motor is satisfied, the manual cycle and the generation cycle are simultaneously performed, and the peak value of the torque is suppressed low. Thus, a torque curve of the motor is obtained. Therefore, since it is not necessary to increase the output of the assist motor, it is not completely synchronized with the manual torque, but the motor can be downsized.

Similarly, the response delay of the motor torque with respect to the human torque is set to 0.4 sec, and the relationship between the motor torque and the human torque on a flat traveling road is as shown in FIG. Although the motor torque required for the assist is small, the synchronization between the human-power torque and the motor torque is so far out of synchronization that the followability is poor, so that it is not like a bicycle and the riding comfort is very poor.

From the above, the response speed of the motor torque with respect to the human-powered torque does not always have the same fixed value when traveling on a flat traveling road and a sloping road. It is understood that it is preferable to increase the response delay when traveling on a slope, and to gradually increase the response delay from a flat traveling road to traveling on a slope.

As a result of these tests, it was derived from the relationship of the response speed of the motor torque to the manual torque that the relationship of the response speed of the control system to the motor torque became a curve as shown in FIG. Therefore, the present invention provides FIG.
When the motor torque is small, the response speed delay is reduced, that is, the response speed is increased, and when the motor torque is large, the response speed delay is increased, that is, the response speed is reduced. By controlling the output of the motor for a bicycle, it is possible to follow the manpower and to obtain a riding comfort similar to that of a bicycle, and to reduce the size of the motor by suppressing the capacity of the assist motor.

Next, the configuration of the output control device of the electric bicycle motor of the present invention which performs the above output control will be described with reference to FIG. In FIG. 10, 8 is an assist motor, 31 is an assist torque setting device, 32 is a comparator, 3
3 is a proportional circuit, 34 is an integrator, 35 is a pulse width modulation (PWM) control device as a current control device, and 36 is a proportional constant setting device. Here, the comparator 32, the proportional circuit 33, the integrator 34, the pulse width modulation control circuit 35, and the proportional constant setting device 36 are referred to as a motor control device.

Next, the output control operation of the above device will be described. The relationship between the manpower torque and the assist ratio according to the notification rules is input to the assist torque setter 31. When the manpower torque is input, the assist torque commander 31 outputs an assist torque command signal required for the assist motor 8.

The comparator 32 compares the input assist torque command with the torque of the motor 8, and compares the deviation with the proportional circuit 3.
3. Proportional / integrate via an integrator 34 and input to a pulse width modulation (PWM) controller 35 at the next stage, which is controlled at a predetermined duty, and a drive current corresponding to the duty is supplied to the motor 8
And an assist torque that satisfies the relationship between the manpower torque and the assist ratio is output.

Here, since the proportional constant setting unit 36 has a table of the relationship between the response speed of the control system and the motor torque shown in FIG. 9, the constant of the proportional circuit 33 corresponding to the motor torque signal is determined. The settings are controlled.
That is, the proportional circuit 33 reduces the response delay on a flat traveling road, increases the response delay on a hill, and gradually increases the response delay from a flat traveling road to a hill. Determine and control the constant.

As a result, as shown in FIG. 11, the relationship between the motor torque and the manpower torque is such that when the vehicle runs on a slope, the response speed of the motor torque with respect to the manpower torque is further reduced so that the condition as the assist torque of the motor is reduced. Is satisfied, the torque curve of the motor is obtained in which the manual torque and the generation cycle are simultaneous and the peak value of the torque is suppressed low. Therefore, it is not necessary to increase the output of the assist motor, so that the motor can be downsized and not completely synchronized with the man-powered torque. You can secure running.

On a flat traveling road, as shown in FIG. 12, the delay of the response speed of the motor torque with respect to the manual torque is reduced so that the condition as the assist torque of the motor can be satisfied and the human torque and the motor torque can be satisfied. It is possible to obtain a bicycle-like riding comfort that is synchronized with the torque and has good followability.

In the embodiment of the present invention, the response speed of the motor drive output with respect to the human torque is changed according to the magnitude of the motor torque. However, the human torque and the motor drive output, that is, the pulse width, are replaced with the motor torque. Modulation control circuit 3
It may be changed according to the value of 5.

The reason is that the motor drive output is calculated in accordance with the human-powered torque, and the motor drive thereby detects the motor torque. Therefore, these three signals have a close relationship and are almost the same. It is because it becomes a value.
That is, since the human torque and the motor drive output have substantially the same value as the motor torque in the present embodiment, the state of execution is almost the same and the same, so that the signal can be substituted.

[0041]

As described above, according to the present invention, by controlling the response speed of the control system according to the motor torque, it is possible to satisfy the condition as the assist torque of the motor on a flat running road and to reduce the manpower torque. And a motor-torque can be synchronized to obtain a riding feeling like a bicycle with good followability.

When the vehicle is running on a slope, the output of the assist motor is reduced by satisfying the condition of the assist torque of the motor, simultaneously with the manual torque and the generation cycle, and by suppressing the peak value of the torque low. Since the motor can be downsized, the weight and cost of the assist type electric bicycle can be reduced, and the battery consumption can be reduced. Further, smooth running can be performed from the output waveform.

[Brief description of the drawings]

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

FIGS. 2A and 2B are a front view and a side view showing a configuration of a board-shaped casing.

FIG. 3 is a layout view of a motor on a board-shaped casing.

FIG. 4 is a conceptual diagram of traveling of an assist type electric bicycle.

FIG. 5 is a diagram showing the relationship between human torque and motor torque (when flat,
Low response speed).

FIG. 6 is a diagram showing a relationship between human torque and motor torque (at a slope,
Low response speed).

FIG. 7 is a diagram showing the relationship between human torque and motor torque (at a slope,
High response speed).

FIG. 8 is a diagram showing the relationship between human torque and motor torque (when flat,
High response speed).

FIG. 9 is a diagram showing the relationship between motor torque and response speed.

FIG. 10 is a diagram showing an embodiment of a motor drive circuit according to the present invention.

FIG. 11 is a diagram showing a relationship between human torque and motor torque (at a slope, when a variable response speed is large).

FIG. 12 is a diagram showing the relationship between human torque and motor torque (when flat, variable response speed is small).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric bicycle main body 2 Front wheel 3 Rear wheel 4 Frame 5 Disc-shaped casing 6 Rotation side casing 7 Fixed side casing 8 Motor 9 Electric drive unit 10 Human power drive unit 11 Pedal 12 Chain 13 Handle 14, 15 Brake lever 16, 17 Wire 18, Reference Signs List 19 brake device 20 brake switch 21 saddle 22 battery unit 23 battery case 24 motor output shaft 25 pulley set 26 reduction mechanism 27 transmission belt 28 last stage pulley 29 rear wheel axle 30 stator 31 assist torque setting unit 32 comparator 33 proportional circuit 34 Integrator 35 Pulse width modulation (PWM) controller 36 Proportional constant setting device

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Toshihiro Matsumoto 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Yoshihiko Maeda 2-5-2 Keihanhondori, Moriguchi-shi, Osaka No. 5 Sanyo Electric Co., Ltd. (72) Inventor Kazuhisa Matsumoto 2-5-5 Keihan Hondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd.

Claims (4)

[Claims] An assist torque setting device for detecting a manpower torque, and a motor control device for driving and controlling a motor based on an output from the assist torque setting device, wherein a motor drive output for the manpower torque according to the magnitude of the manpower torque Output control method for electric bicycle motors that controls the response speed of vehicles. An assist torque setting device that detects a human-powered torque; and a motor control device that controls driving of the motor based on an output from the assist-torque setting device. An output control method for an electric bicycle motor that controls the response speed of drive output. 3. An assist torque setting device for detecting a manpower torque, and a motor control device for driving and controlling a motor based on an output from the assist torque setting device, wherein a motor drive output for the manpower torque is provided according to the magnitude of the motor torque. Output control method for electric bicycle motors that controls the response speed of vehicles. 4. The method according to claim 1, wherein the response speed of the motor drive output with respect to the human torque is increased when the human torque, the motor drive signal, and the motor torque are small, and the response speed of the motor drive output with respect to the human torque is reduced when the motor torque is large. Characteristic output control method of electric bicycle motor.