| 摘要 |
PURPOSE:To enable a position of an attracting portion to be changed correspondingly to the shape and working portion of a workpiece without limiting the working portion by providing movably and fixedly a plurality of vacuum adsorbing portions for holding the workpiece in a chuck body. CONSTITUTION:A chuck body 11 is formed radially with dovetail grooves 14. vacuum attracting portions 12a-12d are fromed on the respective under surfaces with projections to be inserted into the dovetail grooves 14 respectively which guide the athracting portion 12a-12d. A lock screw is vertically threaded into the dovetail 14 to abut against the projection on the under surface of the vacuum attracting portions 12a-12d and fix said portions 12a-12d to the chuck body 11. The vacuum attracting portions 12a-12d are located correspondingly to the shape of a workpiece 24 and the working portion of a tool 25 to hold the workpiece 24. The vacuum attracting portions 12a-12d may be replaced by electromagnetic attracting portions if necessary. |
