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:
Jul. 20, 1993
Filed:
Jul. 15, 1991
Thomas Bronnimann, Liebefeld, CH;
Bieri Hydraulik AG, Liebefeld, CH;
Abstract
A prestressing apparatus for tensioning reinforcement cables in recesses or shafts of structures has a main cylinder-piston unit (15, 17) and a counterforce cylinder-piston unit (16, 22). The two pistons (17, 22) are connected via their piston rods (39, 40) to a fixed arm (2), and the cylinders (15, 16) are connected to a movable arm (10). The main cylinder-piston unit disposed in the middle of the arms and the off-centered counterforce cylinder-piston unit are double-acting. The piston chambers (33, 35, 36, 37) are hydraulically cross-connected. Each side of the counterforce piston has half the piston area of the corresponding communicating side of the main piston, so that the prestressing force (V) and the counterforce (G) are each one-half the pressing force (P). The free ends of the arms extending beyond the main cylinder-piston unit serve to transmit force to the reinforcement