Crushing chamber wear indicator

Claim 1

A LINER FOR A COMMINUTION CHAMBER COMPRISING A WALL HAVING A WEAR SURFACE AND A BACK SURFACE ON A SIDE OF THE WALL OPPOSITE THE WEAR SURFACE, AND A PLURALITY OF U-SHAPED LOOPS OF INSULATED ELECTRICALLY CONDUCTIVE WIRES PARTLY WITHIN THE WALL, EACH OF THE LOOPS HAVING A PAIR OF GENERALLY STRAIGHT SECTIONS SPACED APART AND PARALLEL WITH RESPECT TO EACH OTHER AND SUCH SECTIONS OF ALL OTHER LOOPS, EACH OF THE PAIRS BEING CONNECTED ON ONE END TO DEFINE THE LOOP, EACH OF THE LOOP ENDS BEING WITHIN THE WALL AND SPACED DIFFERENT DISTANCES INWARDLY OF THE WEAR SURFACE WITH THE ENDS OF THE STRAIGHT SECTIONS OPPOSITE THE LOOP ENDS PROJECTING THROUGH AND OUTWARDLY OF THE BACK SURFACE TO PROVIDE CONTACTS OUTWARDLY OF THE BACK SURFACE OF THE WALL AND PROVIDE A PLURALITY OF LOOP CIRCUITS INTO THE WALL UNTIL WEARING AWAY OF MATERIAL FROM SAID WEAR SURFACE BREAKS THE LOOP END OF EACH WIRE AS SAID WIRES BECOME EXPOSED IN THE WORN SURFACE.