Abstract: The invention relates to belt cylinders, i.e. piston rodless operating cylinders in which steel belts, in particular, are used in transferring force; even during production, belts of this kind have the negative property of not being sufficiently straight, instead they are bow shaped and this leads to break downs in that the belts either destroy the flanges on the deflecting rollers in a very short time or, if there are no flanges, they run off the rollers; for this reason despite the technical advantages, belt cylinders have not been successful in practice.A satisfactory operation of these belt cylinders may be achieved if, and only if, the belts which transfer force from the piston to the force pick-up are in absolute alignment.

Abstract: A brake assembly is provided for a fluid operated piston and cylinder device having a force applying cross head operating through a slot in the cylinder wall. The brake assembly is integrated with the cross head and consists of brake lining concentrically arranged about the cylinder for engagement with the outer surface of the cylinder. The brake assembly is actuated by a drive mechanism to engage the cylinder outer surface so as to stop, lock and/or position the piston as required.