Automatic air flow regulator for ventilation system - maintains constant pressure in system where diffusers control room temp. by using pressure sensitive throttle element

摘要

The air flow regulator (10) reduces variations of air flow and noise due to pressure variations caused by diffusers controlling room temperatures in a heating/ventilation system. The housing (24) has an inlet (26) and an outlet (28) hermetically sealed to an outlet pipe (30). A shaft (38) in the outlet pipe is moved axially by a control mechanism (35) receiving a pressure signal (Pc) to compress or expand bellows (34). A throttle element (40) on the shaft is sensitive to variations of pressure difference up and downstream and comprises a piston (42) sliding a tube (41) sliding on the shaft (38). Pressure difference produces piston displacement in an opening (32).