Device for maintaining a flexible line under a substantially constant tensile stress

Claim 1

A device for maintaining substantially constant the tensile stress exerted on a flexible line of given length, having its ends fastened to two holding points moveable with respect to each other, comprising the combination of a return member stationary with respect to one of said holding points and a return member moveable along a determined travel path the flexible line passing successively over said return members while forming at least one loop portion, two hydraulic jacks fed from an accumulator of pressuized fluid, said jacks being articulated at stationary points with moveable to said holding point of the flexible line and supporting said moveable return member, the direction of the jack rods being, for each position of said moveable return member, different from that of the travel path of said moveable return member, said jacks being placed symmetrically with respect to the designed travel path of said moveable return member so as to determine said travel path, said stationary return member consisting of three pulleys rotatable about parallel axes, two of said pulleys being in a common plane and the third one in a plane parallel to said common plane, said moveab e return member comprising two pulleys freely rotatable about a common axis which is perpendicular to the axes of the pulleys forming the stationary return member, the diameter of the pulleys of the moveable return member being substantially equal to the distance between the planes containing the pulleys of the stationary return member said jacks being articulated at one of their ends, about an axis solid with the axes of the moveable pulleys, and at their other ends about axes supported by links, rotatable about the axis of said third pulley of the stationary return member, said links having a first position, corresponding to the operating condition of the device, in which they are interconnected through a transverse rod locking said links in position with respect to said holding point of the flexible line, and a second position, adapted for the transportation of the device, in which said links are brought closer to each other so as to reduce the bulk of the device as much as possible.

Claim 2

A device for maintaining substantially constant the tensile stress exerted on a flexible line of given length, having its ends fastened to two holding points moveable with respect to each other, comprising the combination of a return member stationary with respect to one of said holding points and a return member moveable along a determined travel path the flexible line passing successively over said return members while forming at least one loop portion, two hydraulic jacks fed from an accumulator of pressuized fluid, said jacks being articulated at stationary points with moveable to said holding point of the flexible line and supporting said moveable return member, the direction of the jack rods being, for each position of said moveable return member, different from that of the travel path of said moveable return member, said jacks being placed symmetrically with respect to the designed travel path of said moveable return member so as to determine said travel path, said stationary return member consisting of three pulleys rotatable about parallel axes, two of said pulleys being in a common plane and the third one in a plane parallel to said common plane, said moveab e return member comprising two pulleys freely rotatable about a common axis which is perpendicular to the axes of the pulleys forming the stationary return member, the diameter of the pulleys of the moveable return member being substantially equal to the distance between the planes containing the pulleys of the stationary return member said jacks being articulated at one of their ends, about an axis solid with the axes of the moveable pulleys, and at their other ends about axes supported by links, rotatable about the axis of said third pulley of the stationary return member, said links having a first position, corresponding to the operating condition of the device, in which they are interconnected through a transverse rod locking said links in position with respect to said holding point of the flexible line, and a second position, adapted for the transportation of the device, in which said links are brought closer to each other so as to reduce the bulk of the device as much as possible.