Patent ID: 6268791
Filing Date: 2001-07-31
Classification: B01D,F02M,Y10S

Abstract:
A restriction indicating device for an air filter used with a vehicle having an internal combustion engine, a power source and a passenger compartment, the restriction indicating device being in fluid communication with the air flowing from the air filter to the air intake of the internal combustion engine, the restriction indicating device comprising:a housing having an inner chamber;a base cap assembly attached to said housing;an attachment member attached to the air intake system of the vehicle, allowing fluid communication of the air intake system with said inner chamber of said housing;an indicator cup contained within said housing for indicating the vacuum level within said inner chamber of said housing, said indicator cup being slidably positionable between a first position indicating that the air filter is clean and a second position indicating that the air filter is dirty;a calibration spring biasing said indicator cup toward said first position;a diaphragm attached to said indicator cup and said housing, dividing the interior of said housing from the interior of said base cap assembly;a lock ring fixedly attachable to said indicator cup, said lock ring having a central ring and a lower lip;a lockpin coupled to said base cap assembly, said lockpin having a toothed portion with a plurality of teeth, said lockpin being moveable between a first operating position wherein said lockpin is disengaged from said lock ring, a second operating position wherein any one of said plurality of teeth is releasably engaged with said central ring of said lock ring to retain said indicator cup in a position consistent with the vacuum level of the of said inner chamber of said housing, and a third operating position wherein said toothed portion is disengaged from said central ring and said lockpin engages said lower lip of said lock ring; anda switch assembly actuable with a switch actuator integral with and projecting from said lockpin, said switch assembly actuating an electrical circuit for activating a signal device in the passenger compartment of the vehicle, only when said lockpin is in said third position.