Ssi Medical Services, Inc.

James O Threlkeld

Barry D Hand

William T Sutton

Robert C Novack

Ryszard S Ozarowski

A proportional flow control valve is provided for use with low air loss patient support systems. The valve includes a valve housing having an inlet and an outlet defined therein with a valve passage defined through the housing between the inlet and outlet. A chamber is defined in the housing, the chamber further including a nipple cavity defined in the bottom thereof and a cam stop extending from the bottom into the chamber. A valve spool is rotatably disposed within the chamber. The valve spool includes an alignment nipple fitting into the nipple cavity and a cam defined on the bottom thereof through a predetermined rotational arc. The cam and cam stop cooperate to limit the rotational arc of the valve spool within the chamber. A proportional flow control groove is defined in the valve spool. The flow control groove establishes linear air flow through the valve depending on the angular displacement of the spool within the chamber. A motor is provided mounted to the housing to rotate the valve spool within the chamber and, preferably, a torque limiting clutch is disposed between the motor and valve spool. The valve spool further includes a friction reducing substance coated thereon or impregnated therein, such as teflon or the like, to reduce binding of the valve spool within the chamber.

Growing community of inventors

Denver, NC, United States of America

James O Threlkeld