Magnetic rotation counter for determining number of rotations of hollow shaft of steering wheel in automobile, has bridge for bridging inner ends and outer ends of loops with each other, and domain produced in each closed loop of structure

摘要

The counter (11) has a loop structure provided with two separate helical-shaped loops. Inner ends of the loops are connected with outer ends of the loops at a predeterminable spacing by a soft-magnetic bridge that magnetically closes spirals. The bridge bridges the inner ends and the outer ends with each other, and a domain is produced in each closed loop of the loop structure. Hole-free insulating layers are made of aluminum oxide and silicon dioxide, and hole-free ferromagnetic electrical conductive layers are made of copper and tantalum.