Abstract: Hydraulic system for pivoting the lateral structural parts of a truck upwards and downwards. Hydraulic system includes a hydraulic control unit provided with a hydraulic pump and hydraulic valves; a first hydraulic cylinder and a second hydraulic cylinder for pivoting a first component; and a third hydraulic cylinder and a fourth hydraulic cylinder for pivoting a second component. The hydraulic cylinders are embodied in a single-acting manner with an oil chamber and a spring counteraction. A check valve is provided between the at least one external hydraulic line and the oil chambers, the check valve blocking or enabling a reflux of the hydraulic liquid from the oil chamber into an external hydraulic line. In regulated positions of the lateral structural parts and when the hydraulic pump is not actuated, the check valve blocks backflow of the hydraulic liquid from the oil chamber and the external hydraulic line is depressurized.

Abstract: Hydraulic valve with a valve chest (1) provided with a substantially cylindrical internal chamber (5) which may be closed by a valve disc (9) which with its conical rim (9?) engages the facial rim of the internal chamber (5), an insert member (3) being arranged in a section of the internal chamber (5) and structured as a member of sprocket-like cross-section with circular gaps (3?) between teeth forming valve passages (4) with the internal wall of the chest, the valve disc stem (6) permeating the insert member (3) being a one-piece structure and provided with a safety nut (7).

Abstract: Hydraulic valve with a valve chest (1) provided with a substantially cylindrical internal chamber (5) which may be closed by a valve disc (9) which with its conical rim (9′) engages the facial rim of the internal chamber (5), an insert member (3) being arranged in a section of the internal chamber (5) and structured as a member of sprocket-like cross-section with circular gaps (3″) between teeth forming valve passages (4) with the internal wall of the chest, the valve disc stem (6) permeating the insert member (3) being a one-piece structure and provided with a safety nut (7).

Abstract: Hinge arrangement for pivotally connecting structural parts (1) which in oppositely inclined surfaces facing each other are provided with an open-ended T-shaped undercut elongate groove (3) in which may be inserted from the ends of the groove at least one support component (4) with lugs (4″) corresponding to the cross-section of the groove and with a cylindrical receptacle (4′) for insertion of the hinge axle (L), the support components cooperating with at least one unitary hollow pivot profile (5) arranged between the structural parts and provided with inclined walls (5′) corresponding to the inclined walls of the structural parts and adjacent to the cylindrical receptacles of the support components (4) with two partially cylindrical receptacles (7) into which may be inserted the hinge axle (L) extending through the receptacles of the structural parts so that one or both structural parts may be pivoted by 90° or one of the structural parts may be pivot by 180° relative to the other.

Abstract: The invention relates to a control device for hydraulic power cylinders, in particular power cylinders of a road truck tailgate, comprising a hydraulic pump (1) driven by a motor (M). Said pump can be connected to a supply of medium and, via pump branch pipes, to a chamber of the operating cylinder (14) by means of allocated control valves (12,13). An adjustable electrical pressure gauge and switch unit (15-18) is connected to the chamber or corresponding pump branch pipe of the power cylinder. Said unit is fitted with a computer (15) for entering maximum pressure limits and used to stop the pump motor drive (2, 19) and activate a signal transmitter (20) when a preset maximum pressure is exceeded. In addition, a safety valve (22) set at a cut-in pressure lower than the preset maximum pressure is connected to the chamber or corresponding branch pipe (8″,A,B) via an electromagnetic valve (23) which opens when the device is not operating.

Abstract: The invention is directed to novel steroid intermediate products of general formula I ##STR1## The steroid intermediate products which can be isolated according to the invention are suitable for the synthesis of 13-ethyl-11-methylene-18,19-bisnor-17.alpha.-pregn-4-en-20-in-17-ol (desogestrel).Further, processes for producing the steroid intermediate products of general formula I are described. The olefination of the 11-oxo steroids is carried out under the influence of ultrasound.

Abstract: A hydraulic pressure transmitting apparatus for energizing power cylinders of the kind useful in moving load-carrying platforms on vehicles or the like, being of extremely compact structure on account of a manifold constituted by an end section of a cylinder housing all essential pressure fluid conduits and control valves, as well as connectors for external pressure cylinders being provided with the manifold.