The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 10, 1979
Filed:
Nov. 03, 1977
Werner Schnabele, Wolfratshausen, DE;
Paul VON Malottki, Ottobrunn, DE;
Abstract
An apparatus for braking a free piston which is driven at a high acceleran within a tube and, particularly, in a recoilless firearm, comprises a tube which has a first portion of a first diameter and a second portion of a second diameter greater than the first portion with a transition portion therebetween. A free piston is freely movable in the first portion and it has substantially the same diameter as the first portion. A braking sleeve is secured to the interior wall of the tube in the second portion thereof and it has an edge facing the piston which is beveled inwardly to a knife edge. A deformation ring is carried in the second portion between the braking sleeve and the piston and the piston carries an expanding member which moves outwardly when the piston is moved from the first portion through the transition portion to the second portion to contact the deformation ring and to force it against the edge of the braking sleeve so as to deform the braking sleeve starting from its edge which faces the piston radially inwardly to effect the braking of the piston. In one embodiment, the expanding member comprises a ring carried on the piston which rides in a groove of the piston and which is urged outwardly by gases which propel the piston and which communicate with the groove to a passage defined in the rear face of the piston. In another embodiment, the expanding member includes a ring carried on the opposite end of the piston from the end exposed to the propelling gases with a sleeve having a plurality of longitudinal slits which permit the sleeve to be deflected downwardly by the first portion of the tube in which the piston is movable, but which may move outwardly when the piston moves through the transition zone to the second portion so as to contact a deformation ring which is urged by the expanding member to deform the braking sleeve.