PURPOSE: To reduce the manufacturing cost of a magnetic circuit by using a magnet assembly in which one permanent magnet is bonded to an auxiliary yoke plate.
CONSTITUTION: An unmagnetized permanent magnet 30 of desired shape is firstly positioned and bonded on an auxiliary yoke plate 32 to manufacture a magnet assembly 34 by a method of manufacturing a magnetic circuit used for a head positioning system in a magnetic disk unit. Two assemblies are used as a set, two sets are used to be superposed through a spacer 36 between permanent magnets 30 of the assembly 34, inserted into U-shaped magnetized yoke 38 to be magnetized by a magnetizing magnet 40. Two yokes 38 are assembled to form an artificial circuit 42, and fed into a main yoke assembly 48 made of two main yoke plates 44 and side plates 46. The plates 36 are positioned on the plates 44, clamped, the spacer 36 is then removed to form a magnetic circuit. Thus, the manufacturing cost can be inexpensively reduced.
| JP2009176361 | DISK DRIVING DEVICE |
| JP2533761 | PROBLEM TO BE SOLVED: To control zero track of a disk drive device. |
| JPH0773610 | DRIVING DEVICE OF MINT-DISK PLAYER |
TACHIKAWA KAZUHIKO
SATO MASANORI
| JP59161386B | ||||
| JP59075780B |