CENTER CORE OF MAGNETIC DISK DEVICE AND ITS PRODUCING DEVICE

摘要

PURPOSE:To attain the simple production of a center core with high accuracy by forming a recessed groove part on the pressure surface of a pressure bar and therefore forming the pressure surface simply and with high accuracy without changing the spring constant of the pressure bar. CONSTITUTION:A center core is made of synthetic resin and has a square shaft inserting hole 3 for a disk driving shaft 2. At the same time, a U-shaped pressure bar 10 lierces through a slit 11 in the axial direction at the position where the positioning surfaces 9 and 9 are set opposite to each other within the hole 3 to form in one body. In addition, a recess groove part 12 is formed linearly in the axial direction at the position where a contact is secured with the shaft 2 of a pressure surface 10A. The center core is produced by injeting the synthetic resin through a resin injection path 37 into an annular space part 50 formed with the combination of the 1st mobile and fixed metal molds 27 and 23 and the 2nd mobile and fixed metal molds 29 and 24 respectively.