US Patent 8011114 Vehicle dryer with butterfly inlet valve

A vehicle dryer includes an energy-conserving rotatable inlet butterfly valve to selectively admit or block air to a fan encased in a blower housing. The valve includes a plate mounted on a shaft that extends across the inlet portion of the blower housing. The plate is rotated by its shaft to either an opened position for admitting air into a blower housing, or a closed position for blocking air from entering into the blower housing. A crank arm is coupled to the valve shaft, and a pneumatic cylinder includes a piston rod for turning the crank arm through a ninety-degree angle, thereby rotating the valve plate between its opened and closed positions.