Patent GB-1337115-A (GB)
Title: Fuel supply system for internal combustion engines
IPC: F15C1/00
Filed: 1970-11-19
Abstract: 1337115 Fluid switching circuits MIKUNI KOGYO CO Ltd 19 Nov 1970 [22 Nov 1969]  54996/70 Heading F1P A fuel supply system for an I.C. engine comprises an engine r.p.m. function control circuit E R F, Fig. 6, for controlling fuel flow in conformity with the r.p.m. of the engine, a manifold boosted pressure function control circuit M B F for controlling fuel flow in conformity with the boosted pressure in the manifold, and a summing impact modulator S I M for causing fuel controlled by the two circuits to be injected into the inlet manifold through opposed jets in 1  in 2 , a shield 52 being provided around the injection port in 1  to which a drain 51 is connected, Fig. 7. The circuit E R F comprises a governor 21, a pneumatic pressure control valve C V, a one shot circuit O S C and trigger means T M. A needle valve 27 in the control valve C V is opened by the governor 21 in accordance with the engine r.p.m. to allow air supplied through an inlet port 30 to pass through an exhaust port 31 and be applied as an input to a fluid element F D 1, the deflected output of which is applied to a control port of a second fluid element F D 2. The trigger means T M comprises an inclined cam disc 34 mounted on a shaft driven at approximately one half the r.p.m. of a four-cycle engine and at approxiately the same r.p.m. in the case of a two-cycle engine, and an air jet supply duct 35 through which an air stream is supplied to impinge on the cam disc 34. One impulse output signal is provided for each revolution of the cam disc 34 and this passes through a duct 36 and is applied to the first fluid element F D 1 as a basis for engine r.p.m. function control. A pneumatic pressure control valve FV 1  is connected to a detection aperture 13 in an engine manifold 10 to operate a needle valve 39 so that air passes from an inlet 43 to an outlet 42 in accordance with the manifold pressure. The output from valve FV 1  is applied to a fuel flow control valve FV 2  in order to control the flow of fuel from an inlet 44 to an outlet 42. Part of the output from valve FV 2  is fed to an injection port in 1  of summing impact modulator S I M, through a check valve V 3 , and the remainder is fed to a main injection port of the second stage fluid element F D 2  the output from which is fed through a check valve V1 to an injection port in 2  of summing impact modulator S I M. A tapping 61 from the detection aperture 13 is connected to a control port 50 of a proportioning element P F D to which air is supplied and part of the output from which is fed to through a check valve V 2  in a line 62 to injection port in 2  and the remainder is fed through a check valve V 4  to injection port in 1 . This circuit operates during over-run conditions of a vehicle. In a modification, the direct connection between FV 2  and V 3  is omitted and line 64 emerging from the second fluid element FD 2  is divided into two lines 71, 72 which are connected to valves V 1 , V 3 , Fig. 9. In another modification, valve F V 1  is replaced by a proportional amplifier P F D, Fig. 10. Alternatively, valve FV 1  may be replaced by a transverse impact modulator. A further modification is shown in Fig. 8 in which the summing impact modulator S I M is replaced by a transverse impact modulator type injection element T I M.