Air purifier for protecting motor vechicle occupants from pollution

Claim 1

An air purifier system for the passenger compartment of a passenger motor vehicle, comprising: a plenum having an "Air Purifier" therein; an air inlet for introducing outside air into said plenum; vent means in said plenum for directing air from said plenum into said passenger compartment; means coupled with said plenum for conditioning air introduced into said plenum; means for purifying the air introduced into said plenum, said air purifier including an air filter in said plenum through which air may flow and in which dirt from said air may accumulate to clog said air filter; and monitoring means for generating an electrical signal indicating that said filter is clogged with dirt, said monitoring means including a sensor switch having a moveable sensor plate mounted on the downstream side of and in the path of airflowing through said filter so as to be moved to a first position in which said switch is open and said signal is prevented from being generated, said monitoring means including means for biasing said sensor plate to a second position in the absence of sufficient air flow through said filter when said filter is clogged, said sensor switch generating said signal in response to the movement of said sensor plate to said second position.