Patent ID: 8099747
Filing Date: 2012-01-17
Classification: G11B

Abstract:
1. A disk chucking device which holds a disk having a central hole by sandwiching a vicinity of the central hole of the disk from one surface and another surface vertically in a thickness direction of the disk, wherein the disk chucking device includes: a guide shaft which is inserted into the central hole of the disk; a supporting member which is arranged at the base side of the guide shaft, and supports a vicinity of the central hole at the one surface of the disk; a cylindrical holding member which is arranged so as to approach to or separate from the supporting member in an axial direction of the guide shaft; a plunger which is arranged so as to move along the holding member in the axial direction of the guide shaft; a ball supporting member, which is formed in the plunger at the base side of the guide shaft; a ball which is stored in the ball supporting member and supported slidably in the axial direction of the guide shaft together with the plunger; an elastic member which is locked by the plunger and the holding member, and biases to separate the plunger and the holding member in the axial direction of the guide shaft, and biases to the holding member toward the vicinity of the central hole at the another surface of the disk; a locking portion, which prevents the movement of the plunger in the axial direction of the guide shaft by making contact with the balls, formed at the outside of the guide shaft, and a protrusion, which supports the balls by surrounding together with the guide shaft when the balls are contacted with the locking portion, formed at the inside of the holding member.