Patent ID: 7055195

Claim:
An emergency system for a patient bed comprising: (a) an electrically powered linear actuator operable to drive a back rest of the patient bed from a lowered back rest position to a raised back rest position, and operable to permit the back rest to lower from the raised back rest position to the lowered back rest position without being driven by the linear actuator, the linear actuator comprising a lead screw operable for driving a piston rod to raise the back rest when the lead screw operates in an extending direction and further comprising a disengaging element having a spline to permit disengagement of the piston rod from the lead screw when the lead screw operates in a retracting direction; and (b) an independent electrical activation means for activating the linear actuator to permit the back rest to lower from the raised back rest position to the lowered back rest position without being driven by the linear actuator, the electrical activation means not requiring continued operator attendance for continued lowering of the back rest.