Apparatus for making prestressed concrete

Claim 1

APPARATUS FOR MAKING PRESTRESSED CONCRETE COMPRISING A STRESS BED ON TO WHICH UNHARDENED CONCRETE IS ADAPTED TO BE FED, MEANS FOR CONTINUOSULY FEEDING STRESSING WIRE OVER SAID BED SO AS TO BE SURROUNDING BY SAID CONCRETE AND EMBEDDED THEREIN WHEN THE CONCRETE HAS HARDENED, MEANS FOR CONTINUOUSLY APPLYING A WIRE-TENSIONING LOAD TO SAID WIRE WHEREBY THE WIRE IS MAINTAINED IN A TENSIONED CONDITION, AND A FIXED STRESS-COMPENSATING DEVICE INCLUDED IN SAID LOAD-APPLYING MEANS AND THROUGH WHICH THE WIRE IS FED BEFORE PASSING TO A MOVABLE MEMBER HAVING A CONSTANT LOAD APPLIED THERETO, SAID MEMBER BE SLIDABLE RELATIVE TO SAID STRESS-COMPENSATING DEVICE UNDER THE INFLUENCE OF SAID LOAD TO MAINTAIN CONSTANTLY THE WIRE UNDER A GIVEN TENSION SO THAT THE REACTION INDUCED BY THE TENSION IN THE PRESTRESSING WIRE IS TRANSFERRED BY THE STRESS-COMPENSATING DEVICE TO ACT IN AN OPPOSITE DIRECTION ON THE HARDENED CONCRETE.