William Raymond Acorn
Engineers in Tucson, AZ

5218998, Jun 15, 1993

Apr 1, 1992

7/861514

Gary M. Bakken - Tucson AZ
Phillip E. Branham - Tucson AZ
William R. Acorn - Tucson AZ

F16K 332, F24F 1316

13762528

A linearly adjustable fluid damper of the sliding plate adjustable orifice type damper system having a fixed flat plate with a plurality of specifically arranged trapezoidal shaped apertures therethrough, and a slideably adjustable flat plate also having a plurality of specifically arranged trapezoidal shaped apertures therethrough. The sliding plate is juxtaposed the fixed plate such that apertures of the sliding plate overlap apertures of the fixed plate, and aperture orientation of the sliding plate is reversed that of the orientation of the apertures on the fixed plate. The area of the resultant hexagonal composite orifice through both plates varies non-linearly from full open position to full closed position throughout movement of the sliding plate. The result is that fluid flow from zero fluid flow to maximum fluid flow through the resultant orifice is a straight line relationship with linear displacement of the sliding plate. Dampers comprising this configuration may thus be preset to predetermine openings in fluid flow operations to achieve desired results.