In a construction, including:
- a stationary construction unit;
- a movable construction unit movably mounted on said stationary construction unit;
- a gas spring unit operatively connected to both said stationary construction unit and said movable construction unit, said gas spring unit including a cylinder member having two ends and a cavity defined therein, a piston rod member sealingly guided through an aperture in one of said ends, a piston connected to said piston rod member and defining two working chambers within said cavity, a pressurized fluid in said two working chambers, fluid passage means between said two working chambers, and valve means for opening and closing said fluid passage means;
- first connecting means for connecting one of said members to one of said construction units;
- second connecting means for connecting the other of said members to the other of said construction units;
- the improvement comprising:
- a gas spring device connected to the other of said members and to said second connecting means, said gas spring device including a cylinder element having two ends and a cavity defined therein, a piston rod element sealingly guided through an aperture in one end of said cylinder element, and a pressurized fluid in said cavity;
- one of said cylinder and piston rod elements being connected to said other member of said gas spring unit, the other of said cylinder and piston rod elements being connected to the said second connecting means;
- said piston rod member being movable along a path of movement with respect to said cylinder member between an innermost position and an outermost position, said pressurized fluid within said cylinder member exerting an expelling force onto said piston rod member towards said outermost position when said valve means are open, said piston rod member being lockable in a plurality of positions along said path of movement by closing said valve means;
- said piston rod element being movable along a range of movement with respect to said cylinder element between an innermost position and an outermost position, said pressurized fluid within said cylinder element exerting an expelling force onto said piston rod element towards said outermost position;
- said movable construction unit being lockable in a plurality of positions corresponding to said plurality of positions of said piston rod member with said piston rod element being in its innermost position;
- said movable construction unit being further movable along an additional way of movement adjacent its respective locked position, said additional way of movement corresponding to said range of movement of said piston rod element;
- said movable construction unit exerting a movement-resisting force on both said piston rod member and said piston rod element counteracting to said expelling forces exerted on said piston rod member and said piston rod element by pressurized fluid;
- said expelling force exerted on said piston rod member exceeding said movement-resisting force along the path of movement of said piston rod member;
- and
- said expelling force exerted on said piston rod element by pressurized fluid being smaller than said movement-resisting force at least when said piston rod element is in its innermost position.