HUB UNIT WITH ROTATIONAL SPEED DETECTOR

摘要

PROBLEM TO BE SOLVED: To obtain a rotational speed detector which can be installed in a limited space and whose output is large. SOLUTION: A plurality of through holes 33 are formed at equal intervals in the circumferential direction in a cylindrical tone wheel 29 which is turned together with a hub 3. A ring-shaped sensor 35 which is supported by a nonrotating outer ring 9 via a cover 34 is composed of a permanent magnet 36, a stator 37 and a coil 38. A bend part 40 which is formed at the stator 37 faces the outer circumferential face of the tone wheel 29. Cutouts 41 whose number is identical to that of the through holes 33 are formed at the same pitch as the through holes 33 in the bend part 40.