Patent GB-656305-A (GB)
Title: Improvements in or relating to fuel feeding apparatus for an internal combustion engine
IPC: F02M59/00
Filed: 1948-12-07
Abstract: 656,305. Fuel injection pumps. STEVENS, A. H. (Cummins Engine Co., Inc.). Dec. 7, 1948, No. 31631. [Class 102(i)] [Also in Groups XXVI and XXIX] In a fuel feeding apparatus for a multicylinder internal combustion engine, shown diagrammatically in Fig. 16 and in sectional elevation in Fig. 1, fuel is delivered from a tank 11 by a gear pump 12 through a needle valve 69 controlled by a float 70 in a chamber 13, from whence it is pumped by a gear pump 14 through a filter 75a and a single chamber 75b, into a delivery line 75, through a control valve 80 to a port 43 from whence it is pumped by a fuel metering pump 15 via passages 42, 38, 37, into a distributer 16 and thence into the individual iniector lines 17. A shaft 19 driven by a member 20 at engine crankshaft speed drives the pumps 12 and 14 and a pinion 21 in mesh with a pinion 22 of twice its diameter, the pinion 22 driving a cam disc 25 having equally spaced lobes 27 thereon, and the rotary disc 32 of the distributer which is held against the stationary 'distributer head 33 by a spring 34. The disc 32 has a U-shaped passage 35, one limb of which, 36, is in continual registration with the delivery passage 37 in the head, the other limb, 39, coming into registration with each of the injector lines 17 in turn as the disc rotates. The control valve 80 is a spring-loaded piston valve operating in a sleeve 78 having ducts 77 and 79 which it normally masks, the ducts 77 admitting fuel via passage 76 from the line 75, while the duct 79 admits fuel into a passage 42 leading to the port 43 of the pump 15 and to the passage 37 in the distributer head. The valve is moved to unmask the ducts to deliver fuel to the pump 15 by the action of a lever 86 which bears against the cam disc 25, such action being due to the lobes 27 and occurring when the port 39 is out of register with the injector lines. The pump 15 comprises a sleeve piston 45 into which fits a metering slide valve or throttle valve 49 having a neck portion 54, an axial passage 56, and radial ports 55. The piston 45 is urged to its lowermost position by a spring 47 and is reciprocated by the free end of a lever 61, the centre of which carries a roller 60 which periodically contacts equally spaced lobes 59 on a sleeve 58 secured to the shaft 19. The valve 49 is urged upwards by a spring 53 to its uppermost position corresponding to a closed throttle position since in this position fuel delivered by the pump piston 45 escapes through the ports 55, passage 56, and a port 62. When the valve is moved to its lowermost position, corresponding to fully open throttle, the ports 55 are completely masked by the piston sleeve 45 and all fuel pumped thereby is delivered to the distributer. Fuel being byepassed through the port 62 serves to lubricate the under surface of the piston head. The position of the throttle valve 49 may be adjusted by a lever mechanism actuated by a hydraulic piston 128 operated by fuel supplied through a valve 104 (see Group XXIX) under the control of a governor 101 (see Group XXVI), driven by a bevel gear 97 that meshes with a pinion 98 on the shaft 19.