US2225807A

US2225807A - Cooling of internal combustion engine

Info

Publication number: US2225807A
Application number: US312426A
Authority: US
Inventors: Towler Clifford Owen
Original assignee: Pobjoy Airmotors & Aircraft Lt
Current assignee: Pobjoy Airmotors & Aircraft Lt; Pobjoy Airmotors & Aircraft Ltd
Priority date: 1939-01-24
Filing date: 1940-01-04
Publication date: 1940-12-24
Anticipated expiration: 1957-12-24

Description

Dec. 24, 1940. Q o, TQWLER 2,225,807

COOLING OF INTERNAL COMBUSTION ENGINE Filed Jan. 4, 1940 12 15 g 11 I6 18 I Patented Dec. 24, 1940 UNITED STATES COOLING OF INTERNAL COMBUSTION ENGINE Clifford Owen Towler, Rochester, England, as-

signor to Pobioy Airmotors & Aircraft Limited, Rochester, Kent, England Application January 4, 1940, Serial No. 312,426 In Great Britain January 24, 1939 3 Claims.

In an internal combustion engine the heat which the material of the cylinders takes up from the burning gas requires to be dissipated.

This is in some cases effected by means or water 5 or other liquid surrounding the cylinders, cylinder heads and ports, while in other instances the cooling is effected by means of air and the cylinders and cylinder heads are provided with external fins in order to expose a sufficient surface' to the cooling air.

In all engines deleterious effects are produced when the temperature of the interior walls of the cylinder exceeds a certain value. Heat is transmitted from the burning gases to the cyl-1 inder barrel, cylinder head and exhaust passage in the cylinder head or barrel. Some of the heat generated by the explosions occurring in the cylinder is transmitted to the cylinder and cylinder head through the walls of the cylinder and combustion chamber, and also through the walls of the exhaust port and passage- It has been proposed to reduce the quantity of heat which is so transferred to the cylinder head or barrel byproviding the exhaust passage with a lining of a material of low thermal conductivi-ty, such as asbestos", and also to provide over the lining a sleeve of heat-resisting material to assist in retaining the insulating lining in position. 7 30 It is a matter of considerable difllculty to retain the insulating lining securely in the exhaust passage of the cylinder, and according. to the invention this difllculty is overcome by making the lining an integral part of the cylinder head. This is done by incorporating it in the mould in which the cylinder is to be cast and casting the material of the cylinder around it. In the case where the lining consists of asbestos, it is desirable to support it by means of a'sleeve of heat-resisting material, to the external surfaceoi which the lining is applied, in which case the sleeve and lining are incorporated in'the mould as a unit, but the use of such a supporting sleeve is not essential in all cases.

45 In an engine constructed in accordance with the invention, the quantity of heat transmitted from the exhaust gases to the-material or the size of radiator necessary. In aircraft engines this will decrease the drag of the aircraft, and consequently improve the performance of such aircraft. p

In air cooled aircraft engines the necessary amount of cooling air will be reduced with a consequent reduction in drag, and increased performance of the aircraft.

One form of cylinder constructed in accordance with the invention will now be described 5 in further detail, by way of example, with reference to the accompanying drawing, in which:

Fig. l is a side elevation of the sleeve for supporting the insulating lining;

Fig. 2 is the corresponding end elevation;

Fig. 3 is a section along the line III III in Fig.2;

Fig. 4 is a similar section through the sleeve 7 after coating with the insulating lining, and

Fig. 5 is a ,vertical section through the cylinder head.

The cylinder head In is formed with an inlet passage H and an exhaust passage l2,'the inlet valve l3 and exhaust valve It being shown as poppet valves of conventional construction.

The exhaust passage I2 is provided with an .the paste to the sleeve and baking in an oven until the coating has'set. When perfectly dry the assembly is used as a core in the mould in which the cylinder head is cast. On account of the projecting flanges of the sleeve, which become embedded in'the metal of the casting,

there is no risk of displacement of the sleeve or coating.

Although the drawing illustrates the application of the invention to a cylinder having P ppet valves, it should be understood that itis also applicable to sleeve valve engines, and indeed to the exhaust ports of all types of internal combustion engines.

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

1. In a cylinder for an internal combustion engine having an exhaust port and passage, a heat insulating lining which forms a unitary part of the structure of the exhaust passage, said unitary part being integrally 'united with the material of the cylinder.

2. In a cylinder for an internal combustion engine having an exhaust port, a heat insulating unit which forms a unitary part of the structure of, and is retained in position in the exhaust passage, said unitary part being integrally united with said cylinder, said unit consisting of a sleeve of heat-resisting material, and a layer of heat insulating material disposed on the external surface or the sleeve and constituting-an insulating lining for the walls 01 i 10 the exhaust passage.

3. In a cylinder for an internal combustion engine having an exhaust port, a heat insulating unit which forms a unitary part of the structure 01', and is retained in position in the exhaust passage, said unitary part being integrally united with said cylinder, said unit consisting of a sleeve of heat-resisting material, and a layer of asbestos. disposed on the external surface 01' the sleeve and constituting an insulating lining for the wallspf the exhaust passage.

CLIFFORD OWEN TO W LER.