US 8,721,238 B2 · Tool clamping device

Abstract

In the case of a tool clamping device, in particular, for an operating spindle of a processing machine, with an activation element (3) that can be moved by a drive between a first position, in which the tool clamping device is located in a clamped position, and a second position, in which the tool clamping device is located in a released position, a sensor is present in the form of at least one electrical component for detecting a position of the activation element (3). The sensor is integrated structurally into the tool clamping device and at least one section of the activation element (3) directly forms a component of the one or more electrical components, wherein its position influences an electrical property of this component. The component can be an electrical switch whose closed state depends on the position of the activation element (3) in that at least one section of the activation element (3) is electrically conductive and forms a contact electrode of the switch or a part of such an electrode. However, it could also be a capacitor or an inductor.

Claims20

Dependent claims

A tool clamping device for a work spindle of a machine tool, comprising:

an actuating member, positioned within the tool clamping device, which is displaceable between a first position in which the tool clamping device is in a clamping position and a second position in which the tool clamping device is in a releasing position;
a sensor, disposed within the tool clamping device for detecting an axial position of the actuating member, the sensor
including a capacitive element whose value depends on an axial position of the actuating member;
at least one portion of the actuating member is electrically conductive and forms at least one electrode of the capacitive element;
and
the capacitive element further includes two annular and mutually coaxial electrodes arranged next to one another in an axial direction and having external terminals, wherein an annular and electrically conducting portion of the actuating member covers the two electrodes coaxially and thereby forms with these two electrodes a series circuit of two capacitors, and wherein a cross section of the electrically conductive portion of the actuating member covering the two electrodes varies in the axial direction so that the capacitance value depends on the axial position of the electrically conductive portion of the actuating member.

3 more elements

A clamping device, comprising:

a clamping member;
an actuating member disposed within the clamping device, the actuating member configured to drive the clamping member between a clamping position and a releasing position by being axially displaced;
and
a sensor system disposed within the clamping device for monitoring an axial position of the actuating member, the sensor system including:
a capacitive element having at least two electrodes disposed within the clamping device;
and
an electrically conductive portion of the actuating member positionable to cover the electrodes, when the actuating member is moved axially, to create an electrical effect between at least two of the at least two electrodes, the capacitance value of the capacitive element dependent upon on the axial position of the electrically conductive portion of the actuating member.

4 more elements

Dependencies are inferred from the claim text.

Tool clamping device

Life of this patent

Tool clamping device

Life of this patent

Abstract

Claims20