Rotary pump or motor

Claim 1

IN A ROTARY MACHINE OF THE CLASS DESCRIBED, IMPELLER MEANS COMPRISING A PAIR OF INTERMESHING GEARS, A HOUSING FOR SAID IMPELLER MEANS COMPRISING A GEAR PLATE WITH AN OPENING CONFIGURED CLOSELY TO RECEIVE SAID GEARS AND OF A THICKNESS CORRESPONDING TO THAT OF SAID GEARS, SPACER PLATES AT EACH SIDE OF THE GEAR PLATE AND EACH HAVING AN OPENING SOMEWHAT LARGER THAN THAT IN SAID GEAR PLATE, AND OPPOSED END PLATES ABUTTED AGAINST SAID SPACER PLATES, SAID HOUSING HAVING INLET AND DISCHARGE PASSAGES LEADING TO GEARS AT INLET AND DISCHARGE AREAS, SAID GEARS HAVING OPPOSITELY EXTENDING SHAFTS AND THE END PLATES HAVING OPENINGS FOR RECEIVING THE ENDS OF THE SHAFTS, RELATIVELY THIN WEAR PLATES DISPOSED AT OPPOSITE SIDES OF AND ABUTTING AGAINST THE SIDE FACES OF THE GEARS, SAID WEAR PLATES HAVING SHAPES GENERALLY CORRESPONDING TO THE OPENINGS IN SAID GEAR AND SPACER PLATES AND HAVING OPENINGS FOR SAID SHAFTS AND OPENINGS OF THE SAME SIZE AS AND ALIGNED WITH SAID INLET AND DISCHARGE PASSAGES AND BEING OF A SIZE SO THAT THERIR PERIPHERAL SIDE PORTIONS ABUT AGAINST THE SIDES OF THE GEAR PLATES AND THEIR PERIPHERAL EDGES ARE SPACED FROM THE OPENING DEFINING EDGES OF THE SPACER PLATES TO DEFINE A SEAL RECEIVING SPACE, THE WEAR PLATE THICKNESSES BEING SUBSTANTIALLY LESS THAN THE THICKNESSES OF SAID SPACER PLATES WHEREBY THE WEAR PLATES HAVE FREEDOM FOR MOVEMENT TOWARD THE END PLATES AND THERE ARE PROVIDEZD PRESSURE CHAMBERS AT THE SIDES OF THE WEAR PLATES ADJACENT THE END PLATES, RESILIENT SEALING GASKETS SURROUNDING THE PERIPHERAL EDGES OF EACH OF SAID WEAR PLATES AND HAVING SHORT