Process for reducing scrap vulcanized rubber to finely divided particles

Claim 1

A PROCESS OF REDUCING SCRAP VULCANIZED RUBBER TO FINELY DIVIDED FORM, WHICH COMPRRISES SUBJECTING A MASS OF THE SCRAP IN A CONFINED WORKING SPACE TO INTENSE SHEARING ACTION OF AN ORDER SUCH AS TO BRING ABOUT AN INPUT OF ENERGY AVERAGING NOT LESS THAN 1.5 HORSEPOWER PER POUND OF THE SCRAP, CIRCULATING FLUID COOLING MEDIUM THROUGH THE WALLS OF SAID WORKING SPACE WHEREBY TO PREVENT SAID ENERGY INPUT FROM CAUSING A RISE IN THE TEMPERATURE OF THE MASS ABOVE ABOUT 320*F., CONTINUING SUCH ACTION WHILE MAINTAINING THE SCRAP AT A TEMPERATURE BELOW THAT STATED FOR A PERIOD OF TIME WITHIN THE RANGE OF APPROXIMATELY ONE TO FOUR MINUTES TO CAUSE THE SCRAP TO BE TRANSFORMED INTO A FINELY DIVIDED POWDER WITHOUT SIGNIFICANT DEVULCANIZATION OF THE RUBBER SUCH AS WOULD MANIFEST ITSELF BY SUBSTANTIAL AGGLOMERATION OF THE PARTICLES, AT LEAST 80% OF SAID POWDER BEING SUFFICIENTLY FINE TO PASS A 40 MESH SCREEN, AND DISCHARGING THE THUS POWDERED MATERIAL FROM SAID WORKING SPACE AT THE END OF SAID TIME CYCLE.