Abstract: A gripper assembly with gripper fingers (2) which are mounted so that they can be guided and moved radially inward and outward relative to the main body of the assembly. The gripper fingers (2) are biased radially inward by springs. Fitted in the main body (1) is a finger-opening device (20) with a conical body (21) which moves all of the fingers (2) radially outward together against the action of the springs. If the finger-opening device (20) is then retracted, at least some of the fingers (2) come to rest against the edge of the disc-shaped article. If the device (20) is retracted further, the remaining fingers also come to rest, under the action of their associated springs, against the edge of the disc-shaped article. The conical body (21) in the finger-opening device (20) acts on the fingers (2) via guiding elements (12) fitted inside the main body and connected to the fingers (2) by guiding rods (8).

Abstract: A disk-shaped article is held in a freely floating fashion in a state of equilibrium on account of the vacuum produced by a gas exiting from an annular nozzle 12, due to the aerodynamic paradox known as Bernoulli's principle. Above a facing surface of a support 1, the article is retained so securely that it can be treated with a fluid. Cams 45 are provided all around the annular nozzle 12 as lateral stops for the article. These cams 45 are located eccentrically on shafts 44 rotatable on gear wheels 43 in the support 1. The shafts 44 can be turned via the gear wheels 43 by a gear rim 40 received in the support 1 so that rotation of the cams 45 occurs. A space (31, 33) accommodating the gear rim 40 is separated and sealed off with respect to another space (50, 53, 54) through which the compressed gas flows to the nozzle 12. Consequently, the flow of the compressed gas therethrough is not impaired by the cams 45.