Abstract: The device, which controls operation of the loading magazine in an automatic machine tool and is capable of measuring the handling diameter of single workpieces fed into the machine, comprises a set of jaws located between the magazine and the automatic feed facility, and a transducer which monitors the distance separating the jaws when encompassing the workpiece and relays a corresponding information signal back to the unit which controls the operation of the machine tool as a whole.

Abstract: A method is disclosed which envisages the use of a vertical axis equipment magazine with a number of stations, each occupied by a workholding device, and a change arm that is rotatable through a horizontal plane and which picks up devices singly from the magazine and transfers them to a work rest. The work rest itself is provided with a flat horizontal surface and a vertical cylindrical surface serving to support and locate the device, respectively, and a scraper is employed for the purpose of keeping these surfaces clean. A sensor detects any error in the position of the workholding device relative to the two surfaces.