Cavity pump mechanism

Claim 1

IN A SELF-REGULATING PUMPING MECHANISM FOR FLUENT MATERIAL, APPARATUS COMPRISING, IN COMBINATION, A TUBULAR SHELL, A STATOR MEMBER FIXED IN POSITION ALONG ITS LENGTH, SAID STATOR MEMBER HAVING HELICALLY THREADED INTERIOR SURFACE PORTIONS FORMING A ROTOR MEMBER OPENING THERETHROUGH, SAID STATOR MEMBER FURTHER BEING SUBSTANTIALLY SURROUNDED AND ENGAGED BY SAID SHELL, A ROTOR MEMBER TO COOPERATE WITH SAID STATOR MEMBER, SAID ROTOR MEMBER BEING HELICALLY THREADED WITH ONE LESS HELICAL THREAD THAN SAID STATOR MEMBER TO COOPERATE WITH SAID INTERIOR SURFACE OF SAID STATOR MEMBER, SAID STATOR MEMBER BEING MADE OF A RESILIENT MATERIAL, MEANS FOR MOVING SAID MEMBERS AXIALLY RELATIVE TO ONE ANOTHER, A PASSAGE IN SAID STATOR MEMBER SPACED OUTWARDLY OF AND AROUND SAID INTERIOR SURFACE FOR SUBSTANTIALLY THE ENTIRE LENGTH OF SAID STATOR MEMBER, SAID PASSAGE BEING OUT OF COMMUNICATION WITH SAID ROTOR MEMBER OPENING, A PRESSURE FLUID CONNECTION IN COMMUNICATION WITH THE INTERIOR OF SAID PASSAGE FOR FLUID PRESSURE ADAPTED TO CONTROL BY VARIATION OF PRESSURE THEREIN THE RELATIVE CONTACT FORCE BETWEEN SAID MEMBER IN THE COURSE OF OPERATION, SAID CONNECTION INCLUDING MEANS TO EFFECT SAID CONTROL INDEPENDENTLY OF THE PRESSURE OF THE FLUENT MATERIAL PUMPED BY SAID PUMPING MECHANISM, MEANS OPERATIVELY CONNECTED TO SAID ROTOR MEMBER FOR NORMALLY MAINTAINING SAID ROTOR MEMBER WITHIN SAID STATOR MEMBER TO A PREDETERMINED EXTENT, AND YIELDING MEANS FOR RELATIVELY MOVING SAID MEMBERS AXIALLY APART TO REGULATE TO A PREDETERMINED MAXIMUM THE PUMPING FORCE DEVELOPED BETWEEN SAID MEMBERS BY THE RELATIVE AXIAL ROTATION THEREBETWEEN.