Multiple rotary pumps of the flexible-vane type

Claim 1

A MULTIPLE PUMP HAVING A HOUSING PROVIDED WITH OPPOSED INLET AND OUTLER PASSAGES AND HAVING TWO MAIN CYLINDRICAL BORES THEREIN, IN SIDE-BY-SIDE, SPACED RELATION TRANSVERSELY OF SAID INLET AND OUTLET PASSAGES, SAID HOUSING INCLUDING A THIRD CYLINDRICAL BORE INTERSECTING THE TWO SAID MAIN BORES AND PROVIDING OPPOSED CONCENTRIC CONCAVE ARCUATE SHOULDERS HAVING A COMMON CENTER ON A LINE JOINING THE RESPECTIVE CENTERS OF SAID TWO MAIN CYLINDRICAL BORES, SAID COMMON CENTER BEING LOCATED EQUIDISTANT FROM THE CENTERS OF SAID TWO MAIN BORES AND SAID SHOULDERS BEING LOCATED RESPECTIVELY ON OPPOSITE SIDES OF SAID LINE; A CAM HAVING OPPOSED CONCENTRIC CONVEX ARCUATE SURFACES FITTED WITHIN THE ARCUATE SHOULDERS OF SAID THIRD CYLINDRICAL BORE ON OPPOSITE SIDES OF SAID LINE, SAID CAM BEING PROVIDED WITH TWO OPPOSITELY FACING CAM SURFACES RESPECTIVELY MERGING WITH THE PERIPHERAL WALLS OF SAID TWO MAIN BORES AND CO-OPERATING THEREWITH TO PROVIDE TWO IMPELLER CHAMBERS, ONE DEFINED BY ONE OF SAID PERIPHERAL WALLS AND ONE OF SAID CAM SURFACES AND THE OTHER DEFINED BY THE OTHER OF SAID PERIPHERAL WALLS AND THE OTHER OF SAID CAM SURFACES; AND TWO ROTATABLE IMPELLERS HAVING FLEXIBLE VANES DISPOSED IN SAID IMPELLER CHAMBERS RESPECTIVELY, EACH OF THE FLEXIBLE VANES OF SAID IMPELLERS BEING ALTERNATIVELY ENGAGEABLE WITH THE BORE WALL AND THE CAM SURFACE DEFINING THE RESPECTIVE IMPELLER CHAMBER.