Fluid actuated linear reciprocating apparatus for forcing flowable material through a passageway

Claim 1

AN EXTRUDER FOR WAX OR THE LIKE EXTRUDABLE MATERIAL THAT IS SUBSTANTIALLY SELF-FORM-MAINTAINING AT ROOM TEMPERATURE AND WILL FLOW UNDER PRESSURE, SAID EXTRUDER COMPRISING: (A) A RIGID FROME, (B) AN OUTER ACTUATING CYLINDER, (C) AN INNER THRUSTING CYLINDER COEXTENSIVE AND SUBSTANITALLY IN TRANSVERSE REGISTRY WITH THE OUTER ACTUATING CYLINDER AND COAXIALLY DISPOSED WITHIN THE OUTER ACTUATING CYLINDER, THE CYLINDER WALL OF THE OUTER ACTUATING CYLINDER AND THE CYLINDER WALL OF THE INNER THRUSTING CYLINDER DEFINING BETWEEN THEM AN ANNULAR ACTUATING SPACE AND THE CYLINDER WALL OF THE INNER THRUSTING CYLINDER DEFINING A SOLID THRUSTING SPACE, (D) MEANS RIGIDLY INTERCONNECTING SAID CYLINDERS TO PREVENT RELATIVE MOBEMENT THEREBETWEEN AND FIXEDLY SECURING SAID CYLINDERS TO SAID FRAME, (E) AN ANNULAR ACTUATING PISTON SLIDABLE ALONG A LONGITUDINAL AXIS IN SAID ANNULAR ACTUATING SAPCE, (F) A SOLID THRUSTING PISTON SLIDABLE ALONG AN AXIS PARALLEL TO SAID LONGITUDINAL AXIS, SAAID SOLID THRUSTING PISTON BEING DISPOSED IN THE SOLID THRUSTING SPACE OF THE INNER THRUSTING CYLINDER, (G) SAID ANNULAR ACTUATING PISTON HAVING A FACE SUBSTANTIALLY GREATER IN PRESSURE BEARING AREA THAN THE THRUSTING AREA OF ONE FACE OF THE SOLID THRUSTING PISTON,