Power-assisted bicycle using sensor with multiple non-uniformly distributed magnetic blocks in shell

Abstract

A power-assist bicycle using a sensor having multiple magnet blocks unevenly distributed in a housing. The sensor comprises, sequentially connected, a sensing element, a power-assist model processor (21), a digital-to-analog converter (27), and an operational amplifier (28). The sensing element comprises a rotating disk (1), a fixed disk (40), and, embedded within a cavity of the rotating disk and of the fixed disk, permanent magnet blocks (2) and a Hall element (3). Arranged on the rotating disk (1) are the multiple permanent magnet blocks (2) that are opposite in adjacent magnet polarities and different in spacing intervals. The Hall element (3) on the fixed disk (40) is arranged at a position in proximity to the permanent magnet blocks. The sensor is sleeved on the exterior of a central shaft (51) of the bicycle. The operational amplifier (28) is connected to a motor controller (29). Advantages: the relative positions of the permanent magnet blocks (2) and of the Hall element (3) are fixed, the Hall element (3) is allowed to acquire a rectangular wave signal, thereby facilitating the sensor to output via digital processing an artificially-set power-assist model, power-assist starting point, ending point, and reasonable power, thus allowing for optimal matching between human and machine, and achieving the effect of electricity conservation.

Description

technical field [0001] The invention belongs to the technical field of power-assisted bicycles, in particular to an electric power-assisted bicycle that performs multi-point magnetic induction on a rotating part to provide power-assisted signals. Background technique [0002] The Chinese patent 201020295192.0 "Claw Type Torque Sensing Device" applied by Yebao Vehicle Material Industry (Kunshan) Co., Ltd. discloses a sensing device for power-assisted bicycles. The sensing device includes a magnetic part and an elastic part to sense the torque. sensing device. After a long time of use, the change of the elastic coefficient of the elastic member will lead to changes in the sensing signal and the control effect of the controlled motor, and the power-assisted effect will not match the power-assisted needs of people. Moreover, the design structure of the elastic member is complex and the manufacturing cost is high. [0003] The Chinese patent 01201843.0 "Automatic Detection Devi...

AI Technical Summary

Problems solved by technology

[0015] Disadvantages (1) Using two permanent magnets with no difference to represent the fixed positions of the two pedals, only multiple Halls can be used to represent the pedals Rotation position: There is no difference between the two permanent magnets. The advantage is that the fixed positions of the two pedals can be expressed regardless of the left and right feet, so that the left and right feet can generate power assistance requirements, which can produce the same motor power assistance effect; but the disadvantage is that The permanent magnetic steel itself cannot indicate the rotation position of the pedal, but can only use multiple Halls at different corner positions to indicate the rotation position of the pedal, so it is not possible to use only one Hall, but must use multiple Halls

[0016] Disadvantage (2) Only one Hall cannot be used, but three Halls will inevitably cause the original segmentation error of the three control signals, which will distort the power-assist demand model, naturally The generation of power output is inconsistent with the demand for power assistance: no matter whether the power-assisted bicycle has one or two motors, the sensor signal for controlling the motor can only be controlled by using one sensor signal input to the motor controller; and the patent uses three sensors. If Hall controls the motor, the three control signals of the three Halls must be combined into one combined control signal before it can be input to the motor controller

The sensing parameters of the three Halls cannot be the same, especially due to changes in ambient temperature and long-term use, the sensing parameters of the three Halls may vary greatly. The output voltages are different, resulting in different power output of the motor, and the power output is inconsistent with the power demand; similarly, when the power demand is the same, the outputs of different Halls may be the same voltage, resulting in the same power output of the motor, and also There is a problem that the power output is inconsistent with the power demand

[0017] Disadvantages (3) The combined control signal is prone to signal drift, which makes the combined control signal not match the motor controller, and the power-assisted demand model is distorted: due to changes in ambient temperature and use time After a long period of time, the sensing parameters of the three Halls may vary greatly, and the connection points of the three control signals of the three Halls will inevitably change, so the combined control signals generated by the same boosting demand will produce segmental signal drift. Combining the control signals as a whole produces signal distortion, that is, the power-assist demand model is distorted, causing the motor controller to choose any one of the three control signals as a reference, resulting in the inconsistency between the power-assisted output and the power-assisted demand

[0018] Disadvantage (4) The sensing points cannot be increased arbitrarily. If there are too few sensing points, the motor will not run smoothly, making the rider feel very uncomfortable: due to the disadvantages (1) and (2) are the most important The number of halls is greater than one. Obviously, the more the number of halls, the more serious the shortcomings (1) and (2) are.

Therefore, the power-assisted bicycle provided by this patent can only be a very bad power-assisted bicycle that makes the rider feel comfortable.

[0019] Disadvantage (5) The blind area of ​​the signal is up to 42 degrees, and you can’t get it when you need it when you start it: As we all know, the torque of the bicycle pedal is the smallest at the apex, and the 10-45 degrees away from the apex is the most in need of assistance. area, but the angle between the Halls in this patent is 42.5-43.5 degrees, and there is no Hall in the area where the pedal is 10-42 degrees away from the apex, and there is no control signal. As a result, the power is most needed time, but the motor of the power assist bicycle does not assist

[0020]In a word, this patent is a technical solution of using multiple Halls to control the booster mode, because only multiple Halls can be used to represent the rotation position of the pedal, and multiple Halls The multiple control signals of Hall must have original errors, and the combined control signals are prone to signal drift, which can cause distortion of the assist demand model, that is, the same assist demand at different times, but different assist effects; the more the number of Halls, the more More, the more serious the distortion of the power-assisted demand model is, the quantity is limited, and the less quantity of Hall causes the motor to run unsteadily, which makes the rider feel very uncomfortable and cannot get power-assisted when starting

To make it undistorted to help the demand model, and to ensure the smooth operation of the motor, there are always two issues. It is impossible to have both.

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