ROTATIONAL SPEED DETECTION SENSOR, AND ELECTRICALLY ASSISTED BICYCLE INCLUDING ROTATIONAL SPEED DETECTION SENSOR

摘要

PROBLEM TO BE SOLVED: To provide a rotational speed detection sensor which is easily and surely mountable additionally on an existing wheel, while suppressing cost increase.;SOLUTION: A magnetism generation part 26 includes: a hub fitting component (radial direction positioning component) 28 mounted from the outside in the vehicle width direction to be coaxial with a front wheel 4; and a circular magnet encoder (magnet holding member) 29 having a plurality of magnetic poles 30, and mounted from the outside in the vehicle width direction to be coaxial with the hub fitting component 28. The magnet encoder 29 is fixed to a spoke 19 of the front wheel 4 by a binding body (fastening member) 32, and sandwiches the hub fitting component 28 together with the spoke 19.;COPYRIGHT: (C)2010,JPO&INPIT