Abstract: The present invention provides precision machine vise equipment for use in the NC machining of workpieces which improves the efficiency of the operation by making it possible to insert, secure, and machine some plural number of workpieces, such as two, or more preferably, four, in each cycle of machine operation, while causing each of said workpieces to be precisely located with respect to each of three mutually perpendicular datum planes, and without the necessity of having the machinist or machine operator conduct a positioning or squaring operation. This is done by providing, in accordance with the present invention, in the first place, a two-place precision machine vise of the type described in U.S. Pat. No.

Abstract: By providing apparatus such as that shown in U.S. Pat. No. 4,529,183, but with the removable central jaw bolted from the top and means provided at the handle end of the device to fix the location of the one of the movable jaws of the structure as shown in the above-mentioned patent, there is obtained a particularly useful apparatus which will do everything that can be done with the vise of the above-mentioned patent, plus being able to conduct precision machining upon individual pieces which are considerably larger in the grasped dimension.

Abstract: In precision machining, a workpiece can be rapidly located with respect to three mutually perpendicular datum planes by positioning it within both a main machine vise and a supplemental machine vise held within the main machine vise, with the supplemental machine vise being one that has an overall length extending beyond the grip of the main machine vise, ground and polished planar side surfaces adapted to be positioned so that one of them is in contact with the substantially planar ground and polished bed surface of the main machine vise, and a ground and polished substantially planar base surface on the supplemental vise, which is adapted to be abutted, usually but not necessarily in a vertical position, against the working interior face of the fixed jaw of the main machine vise.

Abstract: To make parts requiring machining with the workpiece vise-held in different orientations, there is provided a precision vise having first and second pairs of jaws, each pair having a member which is fixedly located with respect to a reference location. The invention includes use of a particular form of vise for holding two pieces whereby the screw shaft that rotates to open or close the jaws is tensioned during tightening, which improves accuracy by avoiding bending stresses. When used in conjunction with suitable numerical-control equipment, the vise of the invention greatly increases productivity in the machining of product parts of the kind indicated above.