Abstract: Fluid movers produce at least predominantly laminar flow internally in an axial or a radial direction in a rotor. A fluid mover rotor comprises a matrix of passages of appropriate size to produce at least predominantly laminar flow spaced circumferentially around the rotor. The passages may provide axial, radial or mixed flow. “Appropriate” dimensions may be selected for a specified volume flow rate. In a radial embodiment, a matrix of radially extending passages could comprise walls having an axial height projecting from an annular disk. The passages may be offset with respect to the radial direction to provide an angle of attack that minimizes incidence losses. The matrix structure allows the use of thin-walled passages to minimize blockage of entering air.
Abstract: Multiple foam-filled cells form a cushioned support surface of a seat or mattress. Individual cells may be collapsed by connection through a manifold and valve to a vacuum source. The collapsed cell essentially removes contact pressure in a localized area of the person supported on the surface and restores localized blood flow. After a pre-determined time interval, atmospheric pressure is readmitted to the cell.
Type:
Grant
Filed:
May 19, 2000
Date of Patent:
January 6, 2004
Assignee:
Hill Engineering
Inventors:
Charles C. Hill, Theodore B. Hill, Carly A. Anderson