MOBILE STRETCHER

In a mobile stretcher, in order to change the height position of a patient support mounted on a chassis, the chassis geometry is modifiable by a hydraulic drive system. The drive system includes a linear actuator, a pressure supply unit, and a receiving space for hydraulic fluid. A manually actuatable unlocking valve unit directly connects a lifting working chamber of the linear actuator to the receiving space. The valve unit has a control space delimited by a piston element movably guided relative to the housing of the valve unit and which communicates with a lifting attachment, which communicates with the working chamber. The piston element is operatively connected to a valve body interacting with a valve seat of a relief valve between the lifting attachment and a tank attachment communicating with the receiving space. A mechanical actuation input acts on the valve body, with a spring element interposed.