| 摘要 |
PURPOSE: To detect torque and drive a motor with driving force corresponding to the torque by expanding/contracting an elastic body according to the grade of manual torque in association with the pedaling of a user, and moving magnetic material to change magnetic force generated from a coil. CONSTITUTION: When a motor-assisted bicycle body starts traveling, a chain sprocket 37 and a rotating plate 42 are going to rotate. A spring 40 presses a final stage pulley 29, and a rotating side casing 6 and a rear wheel are rotated to travel. At this time, torsion is generated between a first and a second rotating plates 51, 54 in association with the contraction of the spring 40, and magnetic material moves on a coil 49, so that the magnetic resistance of the coil 49 is shifted into the small state from the large state, that is, the inductance of the coil 49 is shifted into the large state from the small state. Since the grade of a signal inputted to a microcomputer thus differs according to the manual depressing force, a motor is driven according to this grade to assist man power. |
