Patent ID: 7225912

Claim:
A mechanical inspection device attached to the return wheel track of an escalator for mechanically surveying the support wheels of an escalator stair step and identifying support wheels having an acceptable wheel diameter and support wheels having an unacceptable wheel diameter comprising: a) a mounting plate rigidly affixed to the underside of said wheel track, b) an actuator assembly hingedly attached to said mounting plate, said actuator assembly comprising: 1) abase plate, 2) a pair of rocker arms, positioned at opposing ends of said base plate, for hingedly attaching said base plate to said mounting plate, 3) biasing means for selectively positioning said base plate relative to said mounting plate, 4) an actuator cam plate affixed to said base plate such that said cam plate extends upward towards and above said wheel track by a predetermined distance whereby the axle of said support wheel will engage said actuator plate forcing said actuator plate downward if the support wheel axle is below a predetermined distance above said wheel track, 5) sensor means associated with said mechanical inspection device such that said sensor means will cause stoppage of said escalator when said wheel axle engages said actuator plate.