Steady rest

Abstract

In a steady rest (1) for centering a rotationally symmetrical workpiece (2) in the space, consisting of: two housing halves (4, 5) arranged at a distance from one another and firmly connected together, a middle steady rest arm (6) arranged between the two housing shells (4, 5) that is mounted in the housing shells (4, 5) by means of an actuation piston (7) so as to be moved in an axial direction (3) towards the workpiece (2), and two outer steady rest arms (11, 12) that are in a driving connection with the middle steady rest arm (6) workpieces (2) with the largest possible diameters should be held centerd in the space by the steady rest (one), while retaining the greatest possible movement of travel of the actuation piston (7). This is achieved in that the actuation piston (7) is formed from at least one first advance piston (31) and one second advance piston (32) that are mounted in an axially moving relationship with one another, that a pressure space (33) or (34) is assigned to each advance piston (31, 32) of the actuation piston (7) and that a line (35) emerges in each pressure space (33, 34) through which a pressurized medium can be pressed into the particular pressure space (33 or 34) or drawn out of it.

Dependencies are inferred from the claim text.