Fuel injection pumps

Claim 1

IN A FUEL INJECTION PUMP, IN COMBINATION, A CYLINDER; AN INJECTION PISTON MOUNTED IN SAID CYLINDER FOR RECIPROCATION THROUGH INJECTION AND RETRACTION STROKES THEREOF; SAID INJECTION PISTON HAVING AN AXIAL FUEL INJECTION PASSAGE THERETHROUGH HAVING A DISCHARGE OPENING THROUGH THE INJECTION END THEREOF AND HAVING AN INJECTION DISCHARGE PORT THEREFROM THROUGH A SIDE WALL OF SAID PISTON; SAID CYLINDER PROVIDING AN INLET PORT OPENING THEREINTO FOR SUPPLY OF FUEL TO THE INJECTION END OF SAID CYLINDER FOR INJECTION THEREFROM BY AND THROUGH SAID PISTON ON INJECTION STROKES OF THE LATTER; SAID PISTON BEING ALSO MOUNTED FOR ROTATION IN SAID CYLINDER AND BEING ADAPTED TO BE ROTATED IN ONE DIRECTION DURING NORMAL OPERATION THEREOF; SAID CYLINDER PROVIDING A DISCHARGE PORT THEREFROM AT THE INJECTION END THEREOF; SAID PISTON BEING PROVIDED WITH AN ANGULARLY POSITIONED SLOT THEREIN DISPOSED LONGITUDINALLY THEREOF AT AN ANGLE TO THE AXIS OF SAID PISTON IN A DIRECTION OPPOSITE THE DIRECTION OF ROTATION OF SAID PISTON IN NORMAL OPERATION THEREOF; AND SAID PISTON UPON ROTATION THEREOF IN THE DIRECTION OPPOSITE SAID DIRECTION OF NORMAL ROTATION POSITIONING SAID ANGULARLY DISPOSED SLOT IN OPEN COMMUNICATION WITH SAID INLET PORT DURING AN INJECTION STROKE OF SAID PISTON FOR DISCHARGE OF FUEL FROM SAID CYLINDER THROUGH SAID INLET PORT.