Variable delivery oil pumps

Claim 1

VARIABLE DELIVERY FLUID PUMP COMPRISING A CASING, A FLUID SUPPLY MEMBER FOR RECEIVING FLUID UNDER PRESSURE DISPOSED IN SAID CASING, VALVE PLATE MEANS HAVING AN APERTURE THEREIN ECCENTRICALY MOUNTED ON SAID FLUID SUPPLY MEMBER, FLUID EXHAUST MEANS HAVING FLUID EXHAUST PASSAGES DISPOSED THEREIN MOUNTED ON SAID FLUID SUPPLY MEMBER, A FLUID DISTRIBUTOR BLOCK HAVING FLUID DISTRIBUTING PASSAGES THEREIN ROTATABLY MOUNTED ON A PORTION OF SAID FLUID EXHAUST MEANS SO THAT SAID FLUID DISTRIBUTING PASSAGES COMMUNICATE WITH SAID FLUID EXHAUST PASSAGES, A CYLINDER BLOCK HAVING CYLINDERS THEREIN MOUNTED ON SAID FLUID DISTRIBUTOR BLOCK, PISTON MEANS RECIPROCABLY MOUNTED IN SAID CYLINDERS, SAID VALVE PLATE MEANS BEING DISPOSED BETWEEN SAID FLUID DISTRIBUTOR BLOCK AND SAID CYLINDER BLOCK TO CLOSE PART OF SAID FLUID DISTRIBUTING PASSAGES AND TO ALLOW COMMUNICATION OF PART OF SAID CYLINDERS WITH ANOTHER PART OF SAID FLUID DISTRIBUTING PASSAGES, MEANS MOUNTED TO SAID CYLINDER BLOCK TO ROTATE SAME, SWASH PLATE MEANS RECIPROCABLY MOUNTED IN SAID CASING ADJACENT SAID CYLINDER BLOCK SO THAT SAID PISTON MEANS ENGAGE SAID SWASH PLATE MEANS, DIFFERENTIAL PISTON MEANS OPERATIVELY CONNECTED TO SAID SWASH PLATE MEANS AND INCLUDING PISTON RODS ONE BEING OF LARGER DIAMETER THAN THE OTHER, SPRING MEANS ENGAGING SAID DIFFERENTIAL PISTON MEANS IN A DIRECTION TO AID THE SAMLLER OF THE PISTON RODS, AND MEANS FOR INTERCONNECTING THE DIFFERENTIAL PISTON MEANS AND THE FLUID EXHAUST MEANS TO SUPPLY FLUID TO SAID DIFFERENTIAL PISTON MEANS TO CONTROL MOVEMENT OF THE SWASH PLATE MEANS AND THE DELIVERY OF THE FLUID FROM THE PUMPS.