Actuating device for a steady rest

Actuating device for a steady rest for supporting and/or clamping a workpiece, comprising:

• a carrier having a mounting side that is adapted for mounting the steady rest;
• an actuating part that is supported by the carrier so as to be movable in height direction (H) and has, on an outer end, a connecting arrangement for connection with an input part of the steady rest;
• and
• a double-acting pneumatic cylinder mounted to the carrier, the piston of said cylinder being movably coupled to the actuating part via a coupling arrangement,
• wherein the coupling arrangement includes a slide connected to the piston, said slide being supported so as to be movable in longitudinal direction (L) perpendicular to the height direction (H), and further includes at least one slotted gate extending obliquely with respect to the longitudinal direction (L) and the height direction (H), said gate defining a gate path along which at least one gate element of the coupling arrangement is movably guided, wherein the gate path and the longitudinal direction (L) subtend an angle of inclination (α) that is smaller than 45°, and
• wherein the actuating part is connected to the at least one gate element at an inner end opposite the outer end.