Patent ID: 7077030
Filing Date: 2006-07-18
Classification: B23Q,Y10T

Abstract:
1. A machine tool rotational indexing device having a rotary section which is loaded with at least one of a workpiece and a tool, the rotary section is rotationally and indexably mounted in a predetermined rotational angular position and clamped in an indexed position on a fixed base, the device comprising: a rotary-side coupling attached to the rotary section; a stationary-side coupling attached to the fixed base, the rotary-side coupling being arranged coaxially with the stationary-side coupling; a joint coupling disposed adjacent to both the rotary-side coupling and the stationary-side coupling, the joint coupling being arranged to move between a clamped position and an unclamped position, wherein the clamped position is where the joint coupling meshes with both the rotary-side coupling and the stationary-side coupling and the unclamped position is where the joint coupling is spaced apart from both the rotary-side coupling and the stationary-side coupling; and a plurality of rolling elements arranged between the rotary-side coupling and the stationary-side coupling so that a plurality of rolling element rows are formed and a prescribed preload force acts on the rolling elements when the joint coupling is disposed in the unclamped position, wherein a first rolling element row is positioned farther from the joint coupling than a second rolling element row, the rolling element rows being constructed between the rotary-side coupling and the stationary-side coupling so that the prescribed preload force increases on the first rolling element row and the prescribed preload force decreases on the second rolling element row when the joint coupling moves to the clamped position, and an outer surface of the rotary-side coupling being supported on the stationary-side coupling by the first and second rolling element rows.