Belt training apparatus

Claim 1

IN A CONVEYOR SYSTEM HAVING A SUPPORTING FRAME MEMBER, IDLER ROLLERS SUPPORTED BY THE FRAME MEMBER, AND AN ENDLESS BELT DEFINED BY AN UPPER, LOAD CARRYING RUN AND A LOWER RETURN RUN CARRIED BY THE IDLER ROLLERS, THE IMPROVEMENT FOR MAINTAINING THE BELT CENTERED WITH RESPECT TO THE FRAME MEMBER WHILE THE BELT IS MOVING LONGITUDINALLY, SAID IMPROVEMENT COMPRISING: (A) AT LEAST ONE BELT CARRYING, TRANSVERSE IDLER ROLLER PIVOTALLY SUPPORTED ON THE FRAME, SAID ROLLER BEING ARCUATELY MOVABLE RELATIVE TO THE FRAME ABOUT A VERTICAL AXIS; (B) SENSING MEANS POSITIONED IN PROXIMITY TO EACH OF THE LONGITUDINAL EDGES OF AT LEAST ONE RUN OF THE CONVEYOR BELT, SAID SENSING MEANS BEING ADAPTED TO BE ACTUATED BY THE CONVEYOR BELT WHEN THE EDGE THEREOF PROXIMATE SAID SENSING MEANS STRAYS LATERALLY BEYOND A PREDETERMINED POSITION IN A DIRECTION TOWARDS SAID SENSING MEANS; (C) PUMP MEANS RESPONSIVE TO THE ACTUATION OF SAID SENSING MEANS; (D) AN ACTUATING CYLINDER HAVING UPSTREAM AND DOWNSTREAM SIDES AND A PISTON LINEARLY MOVABLE IN OPPOSITE DIRECTIONS RESPONSIVE TO SAID PUMP MEANS; (E) CONDUIT MEANS COMMUNICATING BETWEEN SAID PUMP MEANS AND SAID CYLINDER; (F) LINKAGE MEANS CONNECTING THE PISTON OF SAID CYLINDER TO SAID ARCUATELY MOVABLE IDLER ROLLER WHEREBY ACTUATION OF SAID SENSING MEANS BY A LATERALLY STRAYING EDGE OF THE BELT WILL CAUSE THE PISTON OF SAID CYLINDER TO DISPLACE SAID ROLLER THROUGH SAID LINKAGE MEANS; AND (G) A SUPPLY OF ACTUATING FLUID COMMUNICATION BETWEEN SAID CYLINDER AND SAID PUMP.