Patent ID: 6935571

Claim:
A diffuser for controlling flow of air in an air conditioning system, the diffuser including a first temperature sensitive element for sensing room temperature variations and including a body and a piston which move relatively to one another in response to temperature variations, a second temperature sensitive element for sensing supply duct temperature variations and including a body and a piston which move relatively to one another in response to temperature variations, an airflow control structure including a damper blade having a first position in which airflow is restricted and a second position in which a greater air flow is permitted, and an actuator for displacing said blade between said first and second positions in response to room temperature variations, said actuator including a cam follower, a cam having first and second cam surfaces and which is displaced by said first element as the piston and body of the first element move relatively to one another with room temperature variations, and means connecting said cam to said second element so that said cam is displaced between a first position in which said first surface and follower co-operate when cooled air is flowing in the duct and a second position in which said second surface and follower co-operate when heated air is flowing in the duct, the arrangement being such that in use said first cam surface displaces the damper blade in the direction which increases air flow as the temperature to which the first element is subjected increases, and said second cam surface displaces the damper blade in the direction which increases air flow as the temperature to which the first element is subjected decreases.