GB1253842A - Liquid fuel pumping apparatus for supplying fuel to internal combustion engines - Google Patents

Abstract

1,253,842. Fuel-injection pumps. C.A.V. Ltd. March 3, 1969 [March 8, 1968], No. 11378/68. Heading F1A. Fuel-injection pumping-apparatus for an I. C. engine includes a rotary cylindrical distributer member 11 carrying pumping plungers 13 in a bore 12 communicating with inlet passages 18 and a delivery passage 16, the plungers being actuated by an internally-lobed annular-cam 14 fixed to a body part 10 containing an inlet port 19 and outlet ports 17. Fuel is supplied by a rotary pump 20 through a passage 23 communicating with a stepped bore 25 containing a piston, or "shuttle", 26 and furnished with a stop 27. During inward movement of the plungers fuel flows into the narrow part of the bore 25, which is permanently connected to the bore 12, and into the left hand end of the widest part of the bore 25 by way of a non-return valve 28 until the piston abuts the stop whereafter the remainder of the fuel flows through the passage 16 to one of the ports 17. When bore 12 is being re-charged the piston ejects the fuel in the narrow part of the bore 25 back into the bore 12 while the fuel in the left-hand end of the widest part of the bore 25 is discharged through a variable throttle 29, which if closed prevents return movement of the piston and so causes maximum discharge through the passage 16. The return movement of the piston may be effected by a spring rather than the pressure of the pump 20. The bore 25 may be formed in the member 11. Throttling means may be provided upstream of the port 19, to regulate the flow therethrough from the pump 20.