Patent ID: 7530891

Claim:
A damper for an air flow duct comprising: ducting; a damper element located internally from an inner surface of a circumferential wall of the ducting and movable between a first, closed position and a second, open position; biasing means biasing the damper element into its closed position; and retention means for retaining the damper element in an open position, the retention means comprising: an actuating member; a retention member which is fixed relative to the damper element and can be secured by the action of the actuating member to retain the damper element in an open position, which securing can be released by movement of the actuating member to release the damper element so that the latter is moved by the biasing means into its closed position; a body member which is fixed to an opening in the inner surface and an outer surface of the circumferential wall of the ducting, the body member having a through-hole which passes from an exterior to an interior of the body member; and a movable member in the through-hole and arranged so that it moves when the actuating member moves, the movable member being arranged such that it protrudes or protrudes further from an opening in the exterior of the body member externally from the outer surface of the circumferential wall of the ducting when the actuating member moves to release the damper element.