Abstract: An extensible hitching device for road and rail vehicles is provided comprising a hydraulic actuator (4) having a cylinder (5), a piston (6), a piston rod (15) and a chamber (7) containing a hydraulic fluid; a coupling device (17) adapted for connection to the rear of another vehicle; resilient means urging the coupling device towards the other vehicle; a hydraulic circuit comprising a reservoir (25) connected to the chamber (7) through two ducts (26, 27), one comprising a normally closed valve (28) and the other a hydraulic pump (30); detection means for controlling opening of the valve (28) when the two vehicles, in the hitched position, form therebetween an angle greater than a given angle, and allowing the resilient means to cause the coupling device (17) to extend while driving back into the reservoir (25) the hydraulic fluid contained in the chamber (7) and control means for actuating the pump (30) so that the fluid driven thereby back into the chamber (7) causes the coupling device (17) to retract agai

Abstract: The trailer of the invention comprises a chassis comprising two vertical pivots (14a, 14b) disposed symmetrically with respect to its longitudinal axis (15), two retainer arms (13a, 13b) mounted for pivoting on the pivots (14a, 14b) and intended to receive the front part of the hull of the boat (10) therebetween, an actuating cylinder (16) connecting the arms (13a, 13b) together at their front part, two pad holders (17a, 17b) pivotably mounted at the rear ends of the retainer arms (13a, 13b) and gripper pads (19a, 19b) pivotably mounted on the pad holders (17a, 17b). The retainer arms (13a, 13b) comprise identical toothed sectors (20a, 20b) centered on the pivots (14a, 14b) of the chassis and whose teeth are in engagement along the longitudinal axis (15) thereof.

Abstract: A swinging device for a dredger of the kind having a two-part articulated dredging boom comprises at least one jack having a jack body provided with a piston rod, the jack body and the piston rod being connected respectively by two connecting joints to separate parts, one of which is fixed, while the other pivots and is coupled to the movable dredging arm. The connecting joint of said jack body is located on a yoke which prolongs this body on the same side as the side on which the piston rod extends, the connecting joint of said jack body thus being located in the vicinity of the connecting joint of said piston rod.

Abstract: The screw of a screw-rudder propulsion assembly for a floating vehicle is suspended on the end of a steering shaft which is housed in a tubular casing which is supported on the vehicle. The shaft is rotated to steer the vehicle and the screw is driven by a hydrostatic receiver unit housed in the screw-rubber assembly. A pair of rotating joints through which oil is circulated to the hydrostatic receiver unit, a trust bearing, and the steering drive for rotating the steering shaft are grouped together at the top of the shaft.

Abstract: The invention described consists of a dredger having a floating hull and a two-part boom attached to the hull and extending forwardly therefrom. The rear end of the first part of the boom is hinged to the hull about a horizontal axis, while its front end has a platform also hinged about a horizontal axis, with structure being provided to keep the platform horizontal when this first part of the boom is inclined using a jib and cable. On the platform is a component pivoted about a vertical axis and on this component is pivoted, about a horizontal axis, the second part of the boom, which performs a sweeping dredging movement and has at its front end a disintegrator tool, and the suction inlet of a pipe for removal of dredged material. The structure keeping the platform horizontal may be a mechanical parallelogram, or servo controlled jacks. Piles on the floating hull and on the platform serve to stabilize the dredger on the sea-bed.

Abstract: The invention provides a substantially homokinetic transmission for rotationally connecting two shafts one of which is mounted on a fixed support and the other of which is mounted on a movable support so that its inclination is variable, and comprises two pairs of universal joints each interconnected by a connector of variable length, one pair attached to one of the shafts and the other attached to the other of the shafts; an intermediate shaft of fixed length is interposed between the two pairs of universal joints and this is carried by a third support pivotally mounted on the fixed support, and control means are provided for controlling the inclination of the intermediate shaft in relation to the position of the shaft which has a variable inclination.

Abstract: A screw-rudder assembly is mounted at the bottom of a steering shaft which rotates in a tubular casing which is mounted on slide shoes which slide in vertical slide guides fixed to a support which is mounted on a floating vehicle. A power cylinder connects the tubular casing to the support and slides the casing upwardly to regulate the depth of immersion of the screw and pivots the casing upwardly about upper slide shoes when bottom slide shoes are released through passages in the slide guides, to lift the screw-rudder out of the water.