Abstract: The present invention relates to a coupling system for use at a spindle apparatus of a machine tool, comprising an energy transmission unit with a transmitter coil unit for the contact-free transmission of electrical energy to a receiver coil unit of a tool interface unit with an electrical load and a tool interface portion for accommodation in a tool support of a work spindle of the spindle apparatus, and a coupling interface unit having an interface body element attachable to the spindle apparatus and a second coupling element which is configured to be coupled to a first coupling element of the energy transmission unit by means of a releasable connection.

Abstract: A tool (20) has a machine-side machine connection (21) for connecting the tool to a machine tool (1) for driving the tool in rotation (27) about a rotation axis (29) and for advancing (26) the tool relative to a workpiece, a workpiece-side tool head (22) having one or more cutting edges (25) for machining a workpiece, wherein the diameter (D) of the tool head is greater than 20 mm and wherein the cutting edges (25) of the tool (20) are arranged such that they travel over an area perpendicular to the rotation axis (29), a vibration unit (23) which is designed to set the tool head into rotary vibration (28) about the rotation axis (29), and a power receiving means (24) for wirelessly receiving supplied energy and for supplying electrical energy to the vibration unit (23).

Abstract: In a method for machining a workpiece, a cutting tool is guided relative to the workpiece, with a vibration being superposed, the amplitude of which is at least 5 ?m. A supply circuit for a piezo actuator of a vibrating tool generates a voltage at the voltage output, which has a direct component and an alternating component. A supply system for a piezo actuator of a vibrating tool has the above-mentioned supply circuit which is connected to a secondary coil that is coupled to a primary coil.