Adjustable lever for fire detection system

Claim 1

Rotary regenerative heat exchange apparatus having a housing with inlet and outlet ports for a heating fluid and a fluid to be heated, a matrix of heat absorbent material carried in said housing, means for alternately subjecting said matrix to the heating fluid and to the fluid to be heated, a series of infra-red ray detecting heads arranged to view a portion of the matrix, a series of openings in said housing adapted to simultaneously receive each infra-red ray detecting head, a series of air locks each comprising an open ended enclosure having an open end thereof confronting each opening of the housing, a first lever arm carrying each detecting head, gear means pivoted upon said housing adapted to arcuately move each lever arm from a position within said housing where it faces the matrix of heat absorbent material to a position where it is seated upon an open end of the enclosure that comprises the air lock, a second lever operatively connected to said gear means, a prime mover for reciprocating the second lever, and means for varying the lateral movement of the second lever to permit each infra-red detecting head to simultaneously seat on an open side of said enclosure.