Patent ID: 7846239

Claim:
An automatic four-port selector valve comprising: a casing having an internal space portion; framed partition plates for separating said space portion into first, second, third, and fourth rooms, each framed partition plate having an opening portion; plate-shaped turnable valve bodies for opening or closing the opening portions of said framed partition plates; an inflow port for always letting a gas flow in through it in any instance, a first inflow/outflow port for letting a gas flow in and flow out through it alternately, an outflow port for always letting a gas flow out through it in any instance, and a second inflow/outflow port for letting a gas flow in and flow out through it alternately with said first inflow/outflow port, the ports being provided in said separated four rooms; and a driving means for turning said plate-shaped turnable valve bodies about a rotation shaft, wherein said opening portions include means for independently changing opening ratios (%) thereof, and the opening ratio changing means are movable vertically or horizontally along an inner wall surface of said first or third rooms when said plate-shaped turnable valve bodies are arranged or positioned in said second or fourth rooms or along an inner wall surface of second and/or fourth room when said plate-shaped turnable valve bodies are arranged or positioned in said first or third rooms, and said means are thereby capable of changing the opening ratios (%) of said opening portions.