Patent GB-332523-A (GB)
Title: Cooling of internal-combustion engines
IPC: F02F1/36
Filed: 1929-02-20
Abstract: 332,523. Hewitt, H. S., Whatmough, W. A., and White, P. Feb. 20, 1929. Cylinders, controlling temperature of. - Cooling liquid is circulated at different rates through the cylinder head so that the hot zone near the sparking-plug socket is cooled by a rapid turbulent flow whilst over a larger and comparatively cool zone the flow is retarded. The rate of cooling is such that the hot zone is cooled sufficiently to prevent detonation of the cylinder charges whilst the second zone is maintained at a temperature which prevents deposition of fuel. In a form of cylinder construction in which the cooling liquid is fed by a pump to the cylinder jackets and flows upwardly to a detachable head, Figs. 1, 2 and 3 (not shown), apertures leading from the main block to the head are so proportioned as to promote the necessary rate of flow, suitable baffles being formed in the head to deflect the liquid towards the hot zones; small apertures restrict the flow to other portions of the head. A gasket having suitable apertures may be employed for applying the invention to an existing engine. In Fig. 6 a gallery pipe 10, cast integral with the head, supplies the cooling liquid in high-velocity streams directly to the passages surrounding the sparking- plug sockets 4, whilst apertures 12 and 14 restrict the flow, in the direction indicated by arrows, around the cylinder barrels and other portions of the combustion chamber. In an alternative construction, Fig. 14, a gallery pipe 50 supplies the cooling liquid direct to the cylinder jacket through apertures 51 whilst through the latter are taken conduits 52 which convey the liquid directly to passages 54 surrounding the sparking-plug sockets. Apertures 55 permit a restricted flow to the opposite side of the head. The outlet ends of the conduits 52 are so arranged in the communicating openings between the head and cylinder jackets as to produce an ejector action to assist the circulation. Fig. 15 shows the invention applied to an engine in which the thermosyphon system of circulation is employed. An integrally-formed induction manifold 65 is arranged beneath the exhaust outlets 62, comparative large apertures 61 being provided in the vicinity of the exhaust outlets to induce a flow approximately in the direction shown by the arrows, the induction conduit 65 being surrounded by relatively stagnating liquid. Fig. 11 shows a construction in which the cylinder head jacket is divided into two separate compartments 21, 22 by a longitudinal partition 36. A gallery pipe 20 feeds cooling liquid to the compartment 21 at a point near the sparking-plug socket 30, this being located on that side of the exhaust valve 24 which is remote from the cylinder. The liquid passes through openings leading from a passage 32 surrounding the sparking-plug socket into the cylinder jacket and thence upwardly to a compartment 22 through openings 37. The separate outlets for the liquid leaving the compartments 21 and 22 are controlled by thermostats which may be regulated to maintain the walls of the induction conduit and of the combustion chamber immediately above the cylinder at a different temperature from that existing at the portion of the combustion chamber in the neighbourhood of the exhaust valve. When a completely divided cooling system is used, different cooling fluids may be employed, e.g. water for the hot zone and oil for the remainder. The walls of the combustion chamber may be of aluminium alloy or of thin steel in which ribbed aluminium alloy bosses are fitted to accommodate the sparking-plug. The fluid may be circulated over the hot zones by a pump and over the cooler zones by thermo-syphon action. According to the Provisional Specification, separate thermostats may be employed for controlling the temperature of the liquid entering the separate jackets of a divided cooling system, a common outlet pipe being provided. Also, the hot zone may be water-cooled whilst the remainder may be cooled by air or steem.