US2785664A - Detachable cylinder head constructions for liquid cooled fuel injection compression ignition engines - Google Patents

Description

2,785,664 DETACHABLE CYLINDER HEAD CONSTRUCTIONS FOR C. N. GOLDSMITH Filed May 23, 1955 March 19, 1957 LIQUID COOLED FUEL INJECTION COMPRESSION IGNITION ENGINES IINVENTQR CHARLES N. GoLDsmrrH vg 61, Mm Y ATTORNEYS DETACHABLE CYLINDER HEAD CONSTRUC- TIONS FOR LIQUID COOLED FUEL INJEC- TION COIVIPRESSION IGNITION ENGINES Charles Norman Goldsmith, Shoreham-by-Sea, England, assignor to Ricardo & Co., Engineers (i327) Limited, London, England, a company of Great Britain This invention relates to cylinder head constructions for liquid cooled compression ignition engines of the liquid fuel injection type.

It is an object of the invention to provide improved cooling of a fuel injector arranged in the cylinder head.

According to the present invention a liquid cooled cylinder head for an engine of the kind referred to includes an injector housing extending across the liquid cooling space of the cylinder head, from the outer wall of such space to the inner wall lying adjacent the cylinder bore, and formed integral with or making fluid-tight engagement with each of such walls, and an internal diaphragm wall surrounding but spaced by an annular clearance from the injector housing, and extending across the liquid cooling space so as to divide it into two chambers communicating with one another through the clearance space between the housing and the diaphragm wall, inlet and outlet passages for flow of cooling liquid through the cylinder head being so arranged that a flow of cooling liquid is caused to take place between such chambers 1 through such clearance space.

It will be seen that by suitable choice of dimensions the velocity of the cooling liquid stream passing round the injector housing may be increased, with resultant increase in the cooling etfect. Moreover the arrangement is preferably such that the flow of cooling liquid takes place from the chamber in which the outer end of the housing lies, into the chamber in which the inner end of the housing lies, so that cooling liquid tends to impinge upon the inner face of the inner wall of the head, immediately around the inner end of the housing.

In a preferred construction the axis of the injector housing is inclined to the axis of the respective engine United States Patent O cylinder, and the diaphragm wall includes an annular portion surrounding the injector housing and arranged sub-.

stantially in a plane normal to the axis of the injector housing.

In any case the diaphragm wall is preferably provided with a small aperture adjacent its upper end to permit the escape of air or steam which may accumulate on one side of this wall.

The invention may be performed in various different ways but one specific embodiment will now be described by way of example with reference to the accompanying drawings, in which,

Figure 1 is a fragmentary sectional side elevation through a cylinder head, including part of the associated cylinder block, and,

Figure 2 is a fragmentary sectional plan view on the line II-Il in Figure 1.

In this example the compression ignition engine comprises a water jacketed cylinder block 10 with a detachable water cooled cylinder head 11. The cylinder head is formed with a lower inner wall 12 having a flat surface to engage the upper surface 13 of the cylinder block with the usual interposed gasket seal 14, and an upper outer wall 15 which forms a cooling water cavity with the inper wall 12, with the usual inlet 16 and exhaust 17 passages extending between the inner and outer walls and communicating with inlet and exhaust ports in the inner wall 12 controlled by poppet valves 18, 19.

A bore 20 to receive a fuel injection nozzle is provided in the inner wall 12 of the cylinder head, over each cylinder bore, and the head of each piston closely approaches the inner wall of the cylinder head at the top of its strokeand is formed with a combustion cavity 21 opposite the bore for the fuel nozzle. The cylinder head construction includes a cylindrical injector housing 22 extending through the water cavity in the head with its lower end located in watertight manner in a recess 23 in the inner wall 12 of the head, and its outer end similarly secured in watertight manner to the outer wall 15 of the head.

The injector 22 is inclined to the cylinder axis and-the recess 23 is correspondingly inclined in a raised portion formed on the upper surface of the inner wall of the cylinder head. Each injector housing may for example be inclined to the axis of the respective cylinder at an angle of approximately 20. The fuel injector itself 24 is mounted within the injector housing 22 and the nozzle 25 extends through an aperture in the lower end of the housing 22 and through the bore 20 in the inner wall of the head.

The cylinder head in the neighbourhood of the injector housing 22 is formed with an internal apertured diaphragm wall or web 30 lying between its inner wall 12 and outer walls 15 and including an annular portion 31 lying in a plane normal to the axis of the injector housing 22 and surrounding but spaced therefrom. The diaphragm wall thus provides an annular aperture 32 surrounding the injector housing. Cooling water is admitted tothe water jacket of the cylinder block through an inlet 33, and passes upwards through an aperture 34 in the upper wall of the cylinder block and a corresponding aperture 35 in the inner wall of the cylinder head into the chamber on the upper side of the diaphragm wall 30, and thence downwards through the annular aperture 32 surrounding the injector housing into a chamber surrounding the lower end of the housing. Due to the restricted cross section of the annular aperture 32 the velocity of the cooling water stream through the aperture is increased, with consequent increased cooling efliciency. Moreover the relatively high velocity stream of water issuing into the lower chamber is directed along the sides of the lower end of the injector housing 22 and impinges on the upper surface of the inner wall 12 of the cylinder head immediately surrounding the injector housing, and thus provides efiicient cooling of the lower end of the injector and the adjacent parts of the inner wall of the cylinder head.

From the lower chamber the cooling water passes through the main water cavity in the cylinder head to the usual exit 36. It will be understood also that instead of supplying cooling water to the cylinder head through apertures in the mating surfaces of the cylinder head and the cylinder block, the cooling water may be supplied to the head by an external connection.

To allow air and steam to escape from the chamber on the upper side of the diaphragm wall 30, a small aperture 37 is provided in this chamber adjacent the outer wall of the cylinder head through which air and steam may escape from such chamber into the main cavity of the cylinder head and thence to relief.

What I claim as my invention and desire to secure by Letters Patent is: V

l. A liquid cooled cylinder head assembly for a liquid fuel injection compression ignition engine including an injector housing extending across the liquid cooling space of. the cylinder head from the outer wall of such space to the inner wall lying adjacent the cylinder bore and mak enema Mar. 19, 1957 a ance space between the housing1aridfthe said-diaphragm wall the two ends: of the injectorhousing lying respectively inlathe;said;two chambers, inlet and outlet passages for.

, flow of cooling,liquid:through:the:cylinder-headheing so arranged ,that.:a ,flow of cooling :liquid :is caused to take place between ;such chambers through :suchiclearance space and to impinge on the :inner face of the inner wall 7 0f 'the:head.imm ediately,a1:ound.:theendwf thexhousin'g.

-2.,A liquid-cooled icylinder. head LmnStmctiQn claimed in claim lsin which the axis of ma-injector ihousing inclined ito the axisz-of the respective engine cylinder, :and the diaphragm iwall includesflan annular-portion surrounding xtheainjectorr housing and an-ranged substantially in a plane normal to the axis of the injector houa' claimed 'inclaim 1 'in which the diaphragm wall is p rovidcd with, aismall aperture adjacent its upper .endetoper: mit the escape of air or vapour which may accumulate on one side of this wall. V

4. A liquid-cooled cylinder head construction as i claimed in claim 1 in whichtheinjector housing is separate from theinjector assembly iteelf and'is arranged as a semirpemianent and liquid-tightffitt tlg in the cylinder head. t 1 1 J 'Ref ereuces Clteglin the {file ofthis patent I UNITED STATES PATENTS,

1,107,946 Hesselman ..;Aug. 18, 1914 1,857,744 Schaef May TO, 1932 2,096,344 tSchlaupitz 0ct. -1 9, 3937 2,730,085 Brill t-. Jan. 10, 1956

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