Patent ID: 8519587
Filing Date: 2013-08-27
Classification: B23Q,Y10T

Abstract:
1. An angular indexing apparatus for a machine tool, including a rotating shaft, a housing, a bearing, driving means, and a clamping mechanism, a member that is rotationally driven being secured to one end of the rotating shaft, the housing at least surrounding an outer peripheral surface of the rotating shaft for supporting the rotating shaft, the housing being mountable to and separable from the machine tool, the bearing being provided between the housing and the rotating shaft, the driving means rotationally driving the rotating shaft to index an angular position of the rotating shaft, in which, as the driving means, a drive motor, including a motor rotor and a motor stator, is used, the motor rotor and the motor stator being coaxially disposed around the rotating shaft in the housing, the clamping mechanism maintaining the angular position indexed by the driving means so that the angular position is unrotatable, wherein the driving means includes a plurality of the drive motors disposed in series so as to be separated from each other in an axial direction of the rotating shaft, with the motor rotor of each drive motor being secured to the rotating shaft and the motor stator of each drive motor being secured to the housing, wherein the housing has wiring holes provided in a thick-walled internal portion of an outer cylinder surrounding the outer peripheral surface of the rotating shaft, the wiring holes receiving at least upstream portions in an entire length in a drawing-out direction of cables that are connected to the drive motors, and wherein the wiring holes for the cables, connected to upstream drive motors with reference to the drawing-out direction of the cables, are formed at portions of the housing corresponding to outer sides of downstream drive motors.