GB186369A - Improvements in or relating to means for starting and altering conditions of operating internal combustion engines - Google Patents

Abstract

186,369. Goudge, J. A., (Heywood, C. H.). April 27, 1921. Regulating. - A starting-device for multicylinder four-stroke engines is adapted for augmenting the power developed by so admitting and firing the combustible mixture that the engine works on a two-stroke cycle. The mixture may be supplied to the cylinders by the different forms of the distributing-valves described in Specification 168,614 [Class 7 (v), Internal-combustion engines, Starting &c.]. In one form, Figs. 1 to 4, the valve comprises a seat 1 with ports in communication with the individual cylinders, an angularly adjustable auxiliary seat 2 with tapering ports 3, and a rotary valve disc 4 with two ports 5, 6. For starting, the port 6 is covered bv a segmental shutter 7, which uncovers a smaller port 8; the port 5 then supplies mixture to each cylinder in turn on its power stroke, and the port 8 supplies a smaller quantity to the next cylinder on its compression stroke. For augmenting power when the engine is running, the shutter 7 is moved to uncover the port 6, and at the same time the cam shaft of the engine is adjusted axially or angularly, or both, to bring into position suitable cams for two-stroke working. The exhaust valves are then opened once in each revolution, and the inlet valves are either opened once in each revolution or axe out of action. For controlling the ignition circuits, an electric distributor comprises brushes 38, 38a on an insulating-disc 39 rotating with the spindle 13 of the valve 4. The brushes pass over contacts 36 connected by leads 35 and peripheral contacts 34 on an insulating-ring 33 to the sparking-plugs. On the periphery of the disc 39 are two halfrings 40, 40<a> insulated from each other and connected to the brushes 38, 38<a>. A pair of brushes 41, 42 carried by the ring 33 bear in turn on the half-rings 40, 40a, and the ring 33 also carries a peripheral contact 43. This makes contact with two of the four contacts carried by a ring 45 adjustable angularly by a handle 44 movable between stops 46, 47. The four contacts are connected respectively to an earthed terminal 49, a terminal 50 connected to the brush 42, and terminals 48, 51 connected together. The circuits are indicated in Fig. 11, in which the parts 40, 40<a> are replaced by two slip-rings. For twostroke working, the contact 43 connects terminals 48, 50, and the sparking-plugs are connected in pairs in series, the current passing from one magneto terminal to the other through contacts 41, 36, plug I, earth, plug III, and contacts 38<a>, 42, 50, 43, 48, and 51. When the contact 43 connects the terminals 48, 49, the plugs are connected in pairs in parallel. For normal working, the contact 43 connects the terminals 49, 51 and the plugs spark one at a time. The adjustable ring 45 may be replaced by a switch. The rotary valve shown in Fig. 1 may be replaced by a set of cam-actuated beat valves. The cam shaft is adjustable axially and angularly when changing from a four-stroke to a two-stroke cycle, and may be mounted in eccentric bearings so that the cams may be moved into an inactive position; or the cams may act through wedges which can be withdrawn.