Abstract: When a tube is laid in a duct by a blowing process, the extremity of the tube first introduced in the duct is fitted with an end cap fastened in an airtight fashion on said extremity and fitted with a valve suitable to control the pressure Pint inside the tube, so that is always greater than the pressure Pext in the duct. In this matter, deformations or implosions of the tube are avoided.

Abstract: A pulling apparatus includes a frame having a securing stirrup for securing a beam. The beam is provided at one end with a return pulley. Due to the structure of the securing stirrup, the tractive forces are transferred completely to the beam and the frame so that the means for securing the apparatus to the ground can be minimized. Such a design easily allows the beam to be set at an angle when the pipe is off center. The apparatus may also be easily placed in a cable chamber for operation.

Abstract: A cable (5) is inserted in a tube (2) wound on a tube reel (1). The cable is fed from a cable reel (6) through a cable-advancing unit (4) into a free inlet end (2.1) of the tube (2). Compressed air is applied to an air inlet (8) of the advancing unit (4), and led through the tube along the cable already inserted in the tube. The tube reel is put on a support 7, which is driven to a periodic movement in the vertical direction between to extreme positions (amplitude A, period P). During part of each period the movement is a free fall, or at least approximates a free fall. The movement may be sinusoidal with period P=2.pi.?A/g!.sup.1/2 (g is gravitational constant). In this case, the support (7) may be part of a rotatably supported lever, or may be part of a seesaw. In addition, the movement may be the vertical component of a maintained swinging movement. In this case the support (7) may be the swinging part of a Chinese swing.

Abstract: A cable (5) is inserted, by way of a free end (2.1), into a tube (2) wound around a tube reel (1) which is fixed, with its winding axis (y) vertical, onto a carrier (7). The carrier with the tube reel is subjected to a periodical movement having a vertical component and a longitudinal component. The vertical component is a vertical oscillation having a period (P) and an amplitude (A.sub.v =gP.sup.2 /32) for an, at any rate approximately, "free-fall" movement during part of each period, preferably during half a period. The longitudinal component is an oscillating rotation around the vertical winding axis of the tube reel having the same period (P) and an amplitude (A.sub.L). The "free-fall" movement is preferably commenced when the rotational direction of the oscillating rotation is reversed and becomes backward, as opposed to the insertion direction of the cable.

Abstract: A process and apparatus for stocking cables and other coilable elements such as, for example, hosepipes, pipes and tubes. A stocking device includes a stocking basket formed by a circular outer wall. An edge of a bottom wall serving as a winding base is disposed against the outer wall. A guide member and a fixed or rotary laying stocking device assist in coiling the element. The laying stocking device angularly leads the element to be coiled from the guide toward the stocking basket. At least one height adjustment mechanism is also provided. The height adjustment mechanism adjusts the height of the laying device in order to insure that there is ample space between a stack of the coilable elements in the stocking basket and the laying device. The height adjustment mechanism may be automatic, manual or self regulating.

Abstract: Apparatus for suspending a scaffold or the like, used for working on the outer walls of buildings, comprising a capstan made up of four pairs of pulleys driven by an electric motor. The pulleys have grooves for receiving suspension cables, each of which is wound over a pair of pulleys in five turns. On the slack-portion side, each cable is guided over a traverse mechanism, then runs onto a reel mounted via friction couplings on a shaft. This shaft is driven by the motor when the scaffold is raised, while during the descent it is locked by a monodirectional coupling, a driving wheel then being free on the shaft. A safety release device intended to intervene in case of lessening of the tractive force yielded by the friction couplings is combined with the traverse mechanism. If the tension of the slack portion of cable drops below a given threshold, a safety release cuts off the current supply to the motor and actuates an electromagnetic brake.

Abstract: A cable is supported and advanced by two moving assemblies disposed in the form of a V and each preferably comprising a notched belt of rectangular cross-section. Rollers supporting the notched belts are in turn supported by shafts and are placed overhangingly on these shafts, the lower ends of which are connected to a frame. Neither the frame nor the drive means exceed the driving belts in width. A holding assembly, supported by a framework which has four uprights and also does not exceed the driving belts in width, is removable, and the uprights are hinged to the upper ends of fixed shafts of the intermediate rollers.