Abstract: The invention relates to a telescopic actuator comprising a rod (4), a hollow lead screw (5), a fixed piston (9) comprising a first tail (10) which extends in the lead screw (5) and a head (11). According to the invention, the actuator comprises a first hydraulic connection channel (16) extending through the first tail (10) to fluidically connect a first chamber (C1) with a source of hydraulic fluid (17), and the channel (16) comprises first damping means suitable for slowing down the rod (4) when the latter is depressed by regulating a hydraulic fluid flow rate in the first channel provoked by the depression of the rod.

Abstract: A hydraulic directional valve having an electromagnetic actuating unit and a valve section, an essentially cylindrical, blind hole-like receptacle being formed on one component of the actuating unit, a flange section of a valve housing of the valve section engaging in the receptacle, the flange section being provided with an angular groove which extends in a circumferential direction, and an essentially hollow cylindrical wall of the receptacle in the region of the annular groove engaging in said annular groove in such a way that it bears on the groove base of the annular groove, along the entire circumference of said annular groove. The torsional rigidity between the flange section and the wall is increased. In this context, particular emphasis is placed on processing reliability and economic viability of the connecting process.

Abstract: A hydraulic system for a motor vehicle having a convertible top (2) which can be folded back has a convertible-top control system (1) and further hydraulic control devices (3, 4) which can be activated by a common hydraulic pump (6). In hydraulic lines (8, 9) leading to the convertible-top control system (1) there are arranged hydraulic valves (13, 14) which enable optional operation of the convertible-top control system (1) or of the further control devices (3, 4). Because of this, the hydraulic system turns out to be particularly simple structurally.

Abstract: Disclosed is a tilt-cab truck including apparatus to secure uniform advance and retraction of the tilt cylinders. The system employs a single pilot-operated check valve instead of the conventional two pilot-operated check valves, but it employs two extra check valves to provide the same system safety as is conventionally provided with two pilot-operated check valves.