Encoder

Abstract

Abstract PURPOSE:To make the distance between both poles of respective magnetic marks longer and to increase magnetic force, by making the magnetization direction of the magnetic marks graduated in the circumferential part of a magnetic disc approximately coincide with the radial direction of the magnetic disc. CONSTITUTION:Magnetic marks 3a are magnetized radially along the radial direction of a magnetic disc 3. The marks are magnetized to such polarities at which the directions of the adjacent magnetic marks are alternately reversed in order to improve the discriminating property of the case in which the marks are detected by a head 10. The width in the arc direction of the marks 3a at the circumferential end of the disc 3 corresponds roughly to the thickness of the respective ferromagnetic material films 10a of the head 10 and the space between the marks 3a corresponds roughly to the thickness of the respective non-magnetic material films 10b between the films 10a. The magnetism of the marks 3a is detected by a magnetic detector 10c such as Hall element or the like between the films 10a.

Inventors

• 👤 Kiyoshi Inoue
• 👤 潔 井上

Bibliographic Details