Apparatus for manufacturing clay pipe

Claim 1

APPARATUS FOR MANUFACTURING CLAY PIPE FROM GRANULAR CLAY PARTICLES, COMPRISING IN COMBINATION: AN UPRIGHT MANDREL HAVING A CYLINDRICAL OUTER SURFACE, A SINGLE INTEGRAL UPRIGHT ELASTOMERIC SLEEVE ENCIRCLING SAID MANDREL AND HAVING A CYLINDRICAL BORE EXTENDING FOR A MAJOR PORTION OF ITS AXIAL LENGTH, TO DEFINE AN ANNULAR CAVITY, SAID SLEEVE BEING OPEN AT BOTH ENDS, SAID MAJOR PORTION OF THE ELASTOMERIC SLEEVE HAVING A SUBSTANTIALLY UNIFORM WALL THICKNESS WHICH IS GREATER THAN THE THICKNESS OF THE ANNULAR CAVITY, THE LOWER END OF SAID ELASTOMERIC SLEEVE HAVING AN INTERNAL RECESS, AN AXIALLY MOVABLE END MEMBER HAVING A CENTRAL BORE FOR SLIDABLE RECEPTION OF THE LOWER END OF SAID UPRIGHT MANDREL, SAID END MEMBER SERVING TO CLOSE THE LOWER END OF SAID ANNULAR CAVITY AND HAVING AN UPPER RIM PROJECTING INTO SAID RECESS TO DEFINE AN ANNULAR ENLARGEMENT AT THE LOWER END OF SAID ANNULAR CAVITY, MOVABLE MEANS FOR CLOSING THE UPPER END OF SAID ANNULAR CAVITY, MEANS FOR FILLING SAID ANNULAR CAVITY WITH GRANULAR CLAY PARTICLES THROUGH THE UPPER END OF SAID ELASTOMERIC SLEEVE, HYDRAULIC MEANS FOR CONTRACTING THE ELASTOMERIC SLEEVE TO COMPACT THE CLAY PARTICLES AROUND SAID MANDREL TO FORM A LENGTH OF MOLDED CLAY PIPE WITH AN INTEGRAL BELL IN SAID ANNULAR ENLARGEMENT, AND MEANS FOR LOWERING THE END MEMBER AND THE MOLDED PIPE LENGTH DOWNWARD AS A UNIT OUT OF SAID ANNULAR CAVITY AND AWAY FROM THE MANDREL AND ELASTOMERIC SLEEVE, UPON RELAXATION OF SAID HYDRAULIC MEANS.