Abstract: A drive mechanism for a hospital bed effects relative vertical movement of a base and a patient litter. The drive mechanism includes spaced, telescoping threaded screw assemblies, which are driven by a single electric motor through a train of gears having helical teeth oriented to offset inherent frictional forces of the screw assemblies. A support for the motor and a component of the drive train are made of electrically nonconductive materials to electrically isolate the motor, and are arranged to damp vibrations produced by the motor. Two coiled electrical cords extend between the base and patient litter, and are each received in a recess in the patient litter when the patient litter is adjacent the base. A sensor arrangement provides an electrical signal indicative of the relative vertical positions of the patient litter and base, and a manual drive arrangement is provided to permit the gear train to be manually driven.

Abstract: A hospital bed includes an articulatable patient support with a fowler portion movable between horizontal and inclined positions relative to a frame of the bed. A reversible electric drive motor is supported on the frame of the bed and, through a reduction gearing arrangement and a releasible coupling mechanism, can rotatably drive a threaded shaft. A nut engages and is held against rotation with the shaft, and a linkage arrangement couples the nut to the fowler portion to effect reciprocal movement of the fowler portion in response to reciprocal movement of the nut along the shaft. A manual release is provided on the fowler portion and, when actuated, disengages the releasible coupling mechanism so that the threaded shaft is free to rotate independently of the motor and gearing arrangement.

Abstract: A mattress unit for retarding the development of decubitus ulcers includes a fabric cover having therein a foam material, and includes an inflatable bladder and a control unit disposed within openings in the foam material. The inflatable bladder contains a foam material having spaced holes in it. The control unit includes a pump which can selectively supply pressurized air to the bladder, a valve which can selectively bleed air from the bladder, and a pressure sensor which can determine the current pressure in the bladder. The pressure sensor is coupled to an input of a control circuit which controls the pump and valve. The control circuit receives power from an AC/DC converter and is remotely controlled by a hand-held pendant, the converter and pendant each being physically separate from the mattress unit and being connected to the control circuit by respective cables.

Abstract: A hospital bed has an articulated patient support surface with four air outlet housings mounted thereon at spaced locations. An air supply arrangement supplies temperature-controlled air to an air outlet opening in each of the housings. Associated with each housing is an elongate tubular fabric diffusion member having an O-ring which encircles one end thereof and is removably received in a circumferential groove in the air outlet opening. Each diffusion member can be tucked completely into its housing when not in use. Each housing has a cap movable between open and closed positions with respect to the air outlet opening, and an arrangement yieldably urging the cap toward its closed position. A valve arrangement is provided below two of the housings in order to automatically discharge fluids which happen to enter the air supply system through the air outlet openings.