Sensor with a plurality of magnet blocks adjustable in position and magnetic flux in shell

Abstract

The invention discloses a sensor with a plurality of magnet blocks adjustable in position and magnetic flux in a shell, belonging to the technology of providing a control signal via multi-point-position magnetic induction. The sensor comprises a sensing component, a power-assisted model processor, a digital-analogue converter and an operational amplifier which are sequentially connected, wherein the sensing component comprises permanent magnet blocks and a Hall sensor in inner hollows embedded in a rotating disc and a fixed disc, a plurality of the annularly-distributed permanent magnet blocks are fixedly arranged on the rotating disc, the distances among the permanent magnet blocks and the magnetic fluxes of the permanent magnet blocks at different positions are adjustable, and the magnetic polarities of the adjacent permanent magnet blocks are opposite, that is, the magnetic polarities are distributed by alternately arranging N-poles and S-poles; and the Hall sensor on the fixed disc is arranged at a position close to the permanent magnet blocks. The sensor has the following advantages that: the Hall sensor can obtain a rectangular wave signal via the NS distribution of the magnetic poles, and the rectangular wave signal can participate in digital processing for setting the power-assisted model; and the rectangular wave signal can show the positions of the permanent magnet blocks on the rotating disc and determine the purposes of different rectangular waves by virtue of the difference of the distances and the difference of the magnetic fluxes, and the relative positions of the permanent magnet blocks and the Hall sensor are fixed, so that signal output is reliable.

Description

technical field [0001] The invention belongs to the technical field of providing signals by magnetic induction, and in particular relates to the technology of providing control signals by multi-point magnetic induction on a rotating component. 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 Device ...

AI Technical Summary

Problems solved by technology

[0016] 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 rotational positions of the pedals: the two permanent magnets have no difference, and the advantages It is possible to indicate the fixed position of the two pedals 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 magnet itself cannot indicate the rotation position of the pedals, but only Multiple Halls can be set at different corner positions to indicate the rotational position of the pedal, so one Hall cannot be used, but multiple Halls must be used

[0017] Disadvantage (2) You can’t use only one Hall, but three Halls will inevitably cause the original segmentation error of the three control signals, which will distort the power-assisted demand model, and naturally produce power-assisted output inconsistent with the power-assisted demand: whether the power-assisted bicycle is one or two For a motor, the sensing signal for controlling the motor can only be achieved by inputting a sensing signal into the motor controller to achieve the purpose of controlling the motor; while the patent uses three Halls to control the motor, it is necessary to use the three Halls of the three Halls to control the motor. The signals are combined into one combined control signal before being 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

[0018] Disadvantage (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 long-term use, the sensing parameters of the three Halls may vary greatly , the connection points of the three control signals of the three Halls must change, then the combined control signals generated by the same boost demand will produce segmental signal drift, and the combined control signals will produce signal distortion as a whole, that is, the power boost demand model distortion , causing the motor controller to choose any one of the three control signals as a reference will cause the problem that the power output is inconsistent with the power demand

[0019] 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.

[0020] 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 area that needs the most assistance. , but the included angle between the Halls in this patent is 42.5-43.5 degrees. There is no Hall in the area where the pedal is 10-42 degrees away from the apex, and there is no control signal. The result is when the power is most needed , but the motor of the power-assisted bicycle does not assist

[0021] In short, this patent is a technical solution for using multiple Halls to control the booster mode, because only multiple Halls can be used to represent the rotation position of the pedal, and the multiple control signals of multiple Halls must have original errors, and the combined control signals It is also easy to produce 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 serious the distortion of the assist demand model, limiting the number of Halls , a small amount of Hall will cause the motor to run unsteadily, making the rider feel very uncomfortable, and will not get assistance 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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