Bar screen with improved rake wiping mechanism

Claim 1

IN A BAR SCREEN FOR REMOVING DEBRIS FROM A WASTE STREAM INCLUDING A HOUSING HAVING SIDES EACH PROVIDED WITH SPACED, PARALLEL, VERTICAL GUIDES, BEARING BLOCKS MOVABLY CARRIED BETWEEN SAID GUIDES, A TAKE-UP SCREW AND NUT SUPPORTED BY SAID HOUSING AND SUPPORTING EACH BLOCK BETWEEN THE RESPECTIVE GUIDES, A HEAD SHAFT JOURNALLY CARRIED BY SAID BEARING BLOCKS, A PAIR OF HEAD SPROCKETS FIXED TO SAID HEAD SHAFT WITHIN SAID HOUSING, ENDLESS CHAINS CARRIED BY SAID HEAD SPROCKETS, A RAKE FOR CLEANING THE BAR SCREEN AND CONNECTED TO AND BETWEEN SAID CHAINS; A WIPING BLADE MECHANISM ENTIRELY SUPPORTED BY SAID BEARING BLOCKS COMPRISING A FRAME HAVING TWO MOUNTING ARMS AND A CROSS MEMBER, CORRESPONDING ENDS OF SAID MOUNTING ARMS BEING FIXED TO SAID BEARING BLOCKS WITHIN THE HOUSING, THE ENDS OF SAID CROSS MEMBERS HAVING VERTICALLY ADJUSTABLE BRACKETS CONNECTING THE CROSS MEMBER TO THE MOUNTING ARMS, A WIPING BLADE DISPOSED TO BE ENGAGED BY AND MOVE DOWNWARDLY WITH SAID RAKE AS THE LATTER IS CARRIED BY SAID CHAINS OVER THE SPROCKETS DOWNWARDLY IN THE INVERTED POSITION, A PAIR OF SPACED LEVER ARMS PIVOTALLY CONNECTED INTERMEDIATE THEIR ENDS TO SAID CROSS MEMBER AND HAVING CORRESPONDING ENDS CARRYING SAID WIPING BLADE, COUNTERWEIGHTS FITTED TO THE OTHER ENDS OF SAID LEVER ARMS, CUSHIONING MEANS CONNECTED BETWEEN SAID MOUNTING ARMS AND SAID LEVER ARMS, AND A ADJUSTABLE STOPS CONNECTED TO EACH OF SAID MOUNTING ARMS AND DISPOSED TO