Abstract: A high-load, high-performance, twin-wheeled central-braking caster for a bed is provided having two wheels each comprised of an aluminum core disc and an annular cylindrical flange. The inside of the flanges are covered with elastomeric material in order to serve as brake drums for the wheels. The caster has a central braking mechanism comprising a spring-loaded double-armed brake lever mounted on a pivot pin to guide the brake lever so that it pivots exclusively about a horizontal axis perpendicular to the direction of the wheels' forward rolling movement. The central braking mechanism further comprises a pivot block with an aperture for receiving the pivot pin for mounting the brake lever. The braking mechanism further comprises two compression springs having sufficient spring force to bias the double-armed brake lever away from the wheel.

Abstract: A pressure-relieving therapeutic mattress system that uniquely combines three releasably connected main air cushions that are separately controlled for supporting corresponding portions of a patient at minimal patient interface pressures, together with a sculpted foam sub-mattress supported on a versatile, lightweight frame having a specially-adapted hard pan surface and an efficient, lightweight, variable-speed air supply system.