Abstract: An annular piston and cylinder device comprises an annular cylinder and a piston therefor, the piston having sidewall portions which extend into the cylinder towards the base thereof in the form of tapering annular webs which together define between them a recess of asymmetrical cross section.

Abstract: A fast-acting clamping device for releasably connecting first and second components includes a bolt passing through an opening in the first component and having one end with a head and another end with an anchoring device anchored in an opening in the second component. A cylinder is disposed on the first component, a piston is disposed in the cylinder and a rod is connected to the piston. A lever configuration is connected between the rod and the bolt for generating a clamping force between the head and the first component when a pressure medium is applied to the cylinder.