Rod brake

Abstract

A rod brake includes a housing containing a pressure vessel and a piston intensifier. The pressure vessel has a bearing tube with a bore sized to receive a movable rod. A cavity is provided between an inner wall of the pressure vessel and the bearing tube for a pressure medium carried therein. Access is provided for surface-to-surface contact with a portion of the piston intensifier and the pressure medium. The piston intensifier includes a piston movable by an external force such as a compression spring or air pressure. The piston has an inner face having an annular ring attached or integrally formed with the piston. Alternatively, the piston has a plurality of dowels extending from the inner face. Free ends of the annular ring or dowels are in surface-to-surface contact with the pressure medium so that the force on the piston transmitted over the small contact area of the free ends of the dowels or the annular ring results in a high pressure in the medium providing a braking force against the bearing tube and rod proportional to the pressure in the medium.

Dependencies are inferred from the claim text.