JP2005014869A - Method for controlling assist motor of power-assisted bicycle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate apprehension of battery exhaustion by devising a method of regenerative control to perform running charge without losing assisting feeling in a power-assisted bicycle capable of performing regenerative charge. <P>SOLUTION: In a part where a value of human-powered torque generated in a pedal half cycle is not less than a torque set value set in advance, torque of an assist motor is generated in proportion to the human-powered torque, and in a part where it is not greater than the torque set value, brake torque that is set in advance is generated by the assist motor. The magnitude of the brake torque generated by the assist motor is changed depending on whether there is human-powered torque or the bicycle is in inertial traveling without human-powered torque, thereby reducing a sense of resistance felt by a rider, and achieving power saving. Furthermore, velocity energy including human-powered energy not less than a set velocity is absorbed in a drive source as brake torque. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

001
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling an assist motor of an electrically assisted bicycle capable of regeneration to a drive power source.
[002]
2. Description of the Related Art Even if a conventional electric assist type bicycle can be regenerated, a downhill appears as an effect of using the regenerative function. In this case, it is possible to expect charging of the power source battery by regenerative energy simultaneously with the braking brake effect.
However, as shown in Table 1, when the standard driving pattern is viewed in terms of the power consumption when driving at an assist rate of 100%, the downhill regenerative power amount of 3.1 W is the power running power = (2 × 3 + 6.7). ) = 12.7W to 24.6%.
In addition, the power consumption when there is regenerative travel is 9.6 W compared to the power consumption 12.7 W when there is no regenerative travel, and 12.7 / 9.6 = 1.32 times as the travel distance. However, it is not possible to eliminate the fear of running out of batteries.
[005]
SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks. It is an object of the present invention to recharge the vehicle without losing an assist feeling by devising a regenerative control method and to eliminate the fear of running out of the battery. And
[006]
According to the present invention, the torque of the assist motor is generated in proportion to the manual torque when the value of the manual torque generated during the pedal half cycle is equal to or greater than a preset torque set value. A control method for an assist motor of an electrically assisted bicycle, wherein a preset brake torque is generated in an assist motor in a portion where a human torque is below a torque set value.
In the above control method, the magnitude of the brake torque generated by the assist motor is changed in the case where there is a manual torque due to the pedal depression force and in the inertia running where there is no manual torque. A control method for an electrically assisted bicycle, characterized in that the feeling of resistance felt by the rider is reduced by changing the magnitude of the brake torque.
A control method for an assist motor of an electrically assisted bicycle, wherein the above-described control is applied at a stable traveling speed or higher.
Furthermore, in the electrically assisted bicycle to which the above control is applied, a speed energy equal to or higher than the set speed is absorbed by the drive source as a brake torque including human energy, and is controlled by the electric assist motor.
[0101]
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below.
FIG. 1 shows the relationship between the stepping force and assist force of a conventional general electric assist bicycle without a regenerative function. In FIG. 1, the stepping force (1) and the assisting force (2) are controlled to a relationship of 1: 1 or less.
FIG. 2 shows the relationship between the stepping force (1) and the assisting force (2) of the present invention. For a stepping force portion equal to or greater than a preset threshold value (4), the relationship between the stepping force (1) and the assisting force (2) is assisted at 1: 1 or less, and the stepping force (1) is set to the threshold value (4 ) When it becomes below, the assist motor is controlled as a generator and the traveling energy is absorbed as regenerative power (3).
In FIG. 2, the energy direction of the assist motor is shown as a time chart corresponding to the stepping force (1) with the driving side as (5) and the absorption side as (6). As shown in the figure, the assist motor is driven (5) -regenerative (absorption) side (6) in both directions from the threshold (4) corresponding to the magnitude of the stepping force given by depressing the pedal. It has shown that it has switched to.
Further, it is shown that in the so-called coasting state where the pedal is not depressed and the stepping force (1) is not present, the regenerative traveling state is entered and the traveling energy is absorbed by the power source.
As described above, when a large driving force is required in addition to the stepping force (1), the assisting motor assists the driving force, and when the driving force is small, the inertial energy is absorbed and stored to store the power. At the same time as controlling the energy, it is possible to control to feel the assist.
In FIG. 3, even when there is a pedaling force in the control of FIG. 2, the absorption torque value is the same as the case without the pedaling force below the threshold value, but in this case, the feeling of deceleration increases. Therefore, when there is a stepping force, the absorption torque value is reduced to reduce the feeling of deceleration and improve satisfaction.
In FIG. 4, the brake torque value is changed depending on the running speed. If the brake torque is constant, the absorbed power is proportional to the speed. The value is set to a value that decreases the torque value as the speed increases, weakens the feeling of deceleration, and increases the absorbed power as much as possible.
In order to perform the above control, it is preferable that the bicycle is in a stable running state and is running at a speed of approximately 5 to 7 km / H or more.
In addition, although the power consumption of the power source can be reduced by the control described so far, energy cannot be stored other than traveling downhill. If regenerative running charging can be performed even when the power source energy is exhausted, there is no fear of running out of battery in a conventional electric assist bicycle.
To solve this problem, if the same power is absorbed in a region where the bicycle traveling speed exceeds a certain speed, the inertial traveling can be enjoyed, and the speed can be sensed, the human stepping force burden is Since it is inversely proportional, it takes advantage of the feeling of burden to be reduced, and it is absorbed as regenerative energy including human energy and stored in the drive source.
By controlling in this way, the battery can be stored in a traveling state with a small human torque, such as traveling on a flat road, so that the fear of running out of the battery can be eliminated.
[022]
As described above, the present invention stores human energy as electric energy in places where there is little human load, such as on flat roads, and assists the assist motor with the stored energy in cases where heavy load is applied, such as on slopes. It is used as a force, and by realizing certain functions originally required for a power-assisted bicycle, it solves the anxiety of extended mileage and running out of battery.
In addition, storing human power energy as electric energy places a load on the human body, and can be used as a light fitness equipment for people who use on a flat road, making it another way to enjoy.
Since the vehicle can be recharged, it can be applied to park and ride applications used for commuting to work or school where there is no charging place, and the use of electric assist bicycles can be expanded.
[Brief description of the drawings]
FIG. 1 shows a relationship between a manpower stepping force and a motor assist force when there is no regenerative charging.
FIG. 2 shows a relationship between a manpower stepping force and a motor assist force during traveling charging traveling according to the present invention.
FIG. 3 shows a method for controlling the regeneration amount with and without a stepping force.
FIG. 4 shows control for changing the value of absorption torque according to traveling speed.
[Table 1] Shows the total power consumption between sections and when running standard patterns.
[Explanation of symbols]
1 Stepping force 2 Assisting force 3 Regenerative force 4 Threshold value 5 Drive side 6 Regenerative side

Claims (5)

When the manual torque value generated during the pedal half cycle is greater than or equal to the preset torque setting value, the assist motor generates drive torque in proportion to the manual torque, and when the manual torque is below the torque setting value, A method for controlling an assist motor of an electrically assisted bicycle, wherein a preset brake torque is generated in the assist motor. In the control method according to claim 1, the resistance felt by the rider is reduced by changing the magnitude of the brake torque generated in the assist motor when there is a manual torque due to the pedal depression force and during inertial running without the manual torque. A method for controlling an assist motor of an electrically assisted bicycle. A control method for an electrically assisted bicycle according to claim 1, wherein the feeling of resistance felt by the rider is reduced by changing the magnitude of the brake torque according to the running speed. A control method for an assist motor of an electrically assisted bicycle, wherein the control according to claim 1, 2 and 3 is applied at a stable traveling speed or higher. 5. An electrically assisted bicycle to which claim 1, 2, 3, and 4 are applied, wherein a preset speed energy equal to or higher than a set speed is absorbed by a drive source as brake torque including human power energy. Control method.

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