Longwall mining machines

Claim 1

A LONGWALL MINING MACHINE COMPRISING A ROTARY CUTTING HEAD OF THE SHEARER DRUM TYPE OFFSET LATERALLY FROM THE MINING MACHINE BODY WITH RESPECT TO THE DIRECTION OF TRAVEL OF THE MACHINE, SAID HEAD BEING ADAPTED TO CARRY CUTTER PICKS AND BEING BODILY MOVABLE IN A DIRECTION TRANSVERSE TO THE AXIAL OF ROTATION OF SAID HEAD TO EFFECT CUTTING OF A MINERAL FACE, SAID HEAD BEING FURTHER ADAPTED UPON ROTATION TO DISCHARGE CUT MINERAL AXIALLY OF THE DRUM, SAID MINING MACHINE FURTHER COMPRISING A COWL PLATE HAVING A CURVED SURFACE ARRANGED PATH SWEPT BY THE CUTTER LEL TO A PORTION OF THE CIRCULAR PATH SWEPT BY THE CUTTER PICKS, SAID COWL PLATE HAVING AN AXIAL LENGTH IN THE DIRECTION OF THE AXIS OF THE HEAD AT LEAST EQUAL TO THE AXIAL LENGTH OF SAID HEAD AND A HEIGHT IN A DIRECTION PERPENDICULAR TO SAID FIRST DIRECTION APPROXIMATELY EQUAL TO THE OVERALL DIAMETER OF THE HEAD, AND SAID COWL PLATE BEING SECURED TO A INNER CYLINDRICAL SLEEVE COAXIAL WITH THE AXIS OF CURVATURE OF SAID PLATE AND PIVOTALLY MOUNTED ABOUT THE CUTTER HEAD DRIVE SHAFT TO BE SELECTIVELY LOCATABLE ON EITHER SIDE OF THE AXIS OF ROTATION OF THE HEAD.