Abstract: An actuating system, comprising a base part and a moving part, which can be moved by a compressively preloaded piston/cylinder assembly that comprises a cylinder and a piston rod, wherein a piston on the piston rod divides the cylinder into two working chambers, wherein the base part has an externally powered drive device that stands in operative connection with the moving part and functions in opposition to the operating force of the piston/cylinder assembly, wherein a control system monitors the motion of the moving system and detects an obstacle when a parameter representing the motion deviates from a stored parameter by a threshold limit, wherein the actuating system in the unpowered state holds the moving part with the aid of a locking device, wherein the locking device is formed by a flow connection between the working chambers of the piston/cylinder assembly and a pilot valve for controllably blocking fluid flow through the flow connection.

Abstract: An actuating system, comprising a base part and a moving part, which can be moved by a compressively preloaded piston/cylinder assembly that comprises a cylinder and a piston rod, wherein a piston on the piston rod divides the cylinder into two working chambers, wherein the base part has an externally powered drive device that stands in operative connection with the moving part and functions in opposition to the operating force of the piston/cylinder assembly, wherein a control system monitors the motion of the moving system and detects an obstacle when a parameter representing the motion deviates from a stored parameter by a threshold limit, wherein the actuating system in the unpowered state holds the moving part with the aid of a locking device, wherein the locking device is formed by a flow connection between the working chambers of the piston/cylinder assembly and a pilot valve for controllably blocking fluid flow through the flow connection.

Abstract: Piston-cylinder assembly, in particular gas spring, comprising a cylinder as a first structural unit, in which a piston rod is arranged in an axially movable manner as a second structural unit. An adjusting device exerting an adjusting force includes an acturator and a force-transmitting means operatively connected to the piston-cylinder assembly, the force-transmitting means engaging concentrically on one of the two structural units of the piston-cylinder assembly.

Abstract: An axially movable switching sealing ring within a groove having an axial width greater than the axial width of the ring, in particular in the piston of a piston-cylinder unit, where the switching sealing ring has sealing surfaces on its upper side surface, lower side surface and radial outer wall surface in each instance. The upper and lower side surfaces each have an axially relieved section adjacent the radially outer diameter of the ring, so that the upper and lower sealing surfaces are formed optimally by only part of the upper and lower side surfaces.

Abstract: In a belt drive, a tensioning roller acts onto a section of a belt. The tensioning roller is biased along a tensioning roller movement path such as to provide a tension of the belt. The tension of the belt is responsive to the driving direction of the belt. A higher tension occurs in a normal driving direction of the belt, and a lower tension occurs in a reverse driving direction of the belt. In the reverse driving direction of the belt there is a risk of disengagement between the belt and respective belt pulleys. A damper is provided for damping the movement of the tensioning roller along the tensioning roller movement path. In order to prevent disengagement of the belt and the respective belt pulleys, the damper is locked when a reverse driving direction occurs and/or when operational conditions occur under which there is a likelihood of the reverse driving direction to occur.

Abstract: In an arrangement of gas springs as weight counter-balance and retaining device for a part pivotable substantially about a horizontal axis such as a flap, lid or door, a simple construction is required which guarantees two stable open positions for the pivotable part. This is guaranteed in that two gas springs are arranged where the first of the two gas springs possesses an outward thrust force acting over the entire range of displacement of the pivotable part, while the second gas spring possesses an outward thrust force acting over a part of the displacement range and an additional force-free displacement range.

Abstract: A taper connection between a chair column and a seat plate is proposed. The external taper of the chair column adjoins a cylindrical section of the chair column. The internal taper of the seat plate, fitted together with the external taper of the chair column, protrudes beyond the transition between cylindrical section and external taper.

Abstract: A gas spring particularly for jumping stilts comprises a working cylinder and a plunger. In the working cylinder there is a working chamber containing a mass of gas. A gas exchange chamber is fixed with respect to the working cylinder. An exchange passage connects the working chamber and the gas exchange chamber. A gas exchange valve is provided in the exchange passage. An exchange operating handle is provided separate from the plunger.