Abrading machine

Claim 1

IN AN ABRADING MACHINE, THE COMBINATION OF, AN ENDLESS ABRADING BELT; MEANS SUPPORTING SAID BELT FOR MOVEMENT ALONG A CONTINUOUS PATH, SAID SUPPORTING MEANS INCLUDING A TILTABLE STEERING ROLL FOR INDUCING INWARD AND OUTWARD EDGEWISE TRAVEL OF SAID BELT UPON BACK AND FORTH TILTING OF SAID ROLL BETWEEN TWO OPPOSITELY INCLINED POSITIONS; A RECIPROCATING PNEUMATIC ACTUATOR FOR TILTING SAID ROLL BETWEEN SAID POSITIONS; A DEVICE FOR SENSING EDGEWISE TRAVEL OF SAID BELT TO THE TWO EXTREMES OF A PRESELECTED RANGE OF LATERAL TRAVEL COMPRISING INNER AND OUTER RECEIVERS SPACED APART LATERALLY OF SAID BELT ALONGSIDE THE PLANE THEREOF AND OPENING TOWARD SAID PLANE, INNER AND OUTER NOZZLES RESPECTIVELY ALINED WITH SAID RECEIVERS TO DIRECT JETS OF AIR ACROSS SAID PLANE INTO THE RECEIVERS, SAID RECEIVERS BEING SUPPORTED ADJACENT ONE EDGE OF SAID BELT FOR BACK AND FORTH MOVEMENT OF SAID EDGE BETWEEN AN OUTER POSITION IN WHICH BOTH RECEIVERS ARE COVERED AND AN INNER POSITION IN WHICH BOTH RECEIVERS ARE UNCOVERED, FIRST MEANS OPERABLE IN RESPONSE TO THE PRESSURE RISE IN SAID INNER RECEIVER PRODUCED BY UNCOVERING THEREOF BY SAID BELT DURING INWARD MOVEMENT OF THE BELT TO OPERATE SAID ACTUATOR TO TILT SAID ROLL IN A DIRECTION TO INDUCE OUTWARD TRAVEL OF SAID BELT, SECOND MEANS OPERABLE IN RESPONSE TO THE PRESSURE DROP IN SAID OUTER RECEIVER PRODUCED BY COVERING THEREOF BY SAID BELT TO OPERATE SAID ACTUATOR AND TILT SAID ROLL IN A DIRECTION TO INDUCE INWARD TRAVEL OF SAID BELT, AND MEANS RECEIVING EXHAUST AIR FROM SAID ACTUATOR IN BOTH DIRECTIONS OF OPERATION THEREOF AND DIRECTING SAID EXHAUST AIR OUT THROUGH SAID INNER RECEIVER WHEN THE LATTER IS COVERED AND OUT THROUGH SAID OUTER RECEIVER WHEN THE LATTER IS UNCOVERED THEREBY TO CLEAN EACH RECEIVER ONCE DURING EACH CYCLE OF SAID ACTUATOR WHILE THE RECEIVER IS INACTIVE.