Patent ID: 8695023
Filing Date: 2014-04-08
Classification: B23Q,G11B

Abstract:
1. A medium holding unit for holding a plate-shaped medium, comprising: a holding portion including at least three pressing members which are operable to press an inner peripheral of a hole formed on the medium, wherein the pressing members are movable between first positions where the pressing members do not come in contact with the inner peripheral and second positions where the pressing members come in contact with and press the inner peripheral; wherein each of the pressing members is adapted to interlockingly move with each other when moving toward the first positions and each of the pressing members is adapted to move independently of each other when moving to the second positions such that each of the pressing members can move a different radial distance when moving from the first position to the second position, wherein the holding portion includes pivoting members each having one of the pressing members, wherein each of the pivoting members is engaged with the other pivoting members so as to be interlockingly moved with each other when the pressing members are being moved toward the first positions, wherein the holding portion includes urging members, wherein each of the urging members is suspended over adjacent pivoting members, and wherein the urging members urge the pressing members to the second positions.