Lubrication system for an internal combustion engine

Field of invention

The present invention relates to a "Lubrication system for an internal combustion engine" and more particularly to a gasket construction including polymer members attached with a metal strip for metering the lubricating oil through the openings in the metallic strip.

Description of the prior art

Internal combustion engines has gaskets employed in the cylinder head for interposing compression between the mating surfaces of the cylinder head and the cylinder block for effecting the fluid-tight sealing thereof.

In known type internal combustion engines, the gaskets are generally provided to seal between the cylinder head and the cylinder block of an internal combustion engine. Also the gasket body is formed with at least one hole for a combustion chamber of the internal combustion engine.

In basic construction, gaskets of such type are conventionally constructed of a generally planar member formed of one or more layers of polymers and a metallic material. The metallic material has one cylinder bore opening formed there through for registration with a corresponding combustion chamber of the cylinder head and cylinder block.

Also the lubrication oil and fluid passageways of the cylinder head and cylinder block are typically provided about' the circumference of the cylinder bores for effecting lubrication requirements of the internal combustion engine.

However the above-described arrangement with respect to cylinder head gasket and the lubricating oil openings, which are independently placed, results in increased engine size and production cost. Also the metering of lubricating oil with the present arrangement is not effective with respect to the lubrication requirements of the various parts of the internal combustion engine.

And hence there exists a need for a gasket arrangement that seals between the cylinder head and the cylinder block of an internal combustion engine, with a provision for metering the lubricating oil through the openings in the metallic strip.

Therefore, an object of the present invention is to provide a cylinder head gasket which meters the lubricating oil through the openings in the metallic strip and sealing the cylinder head and the cylinder block of the internal combustion engine.

Another objective of the present invention is to provide a cylinder head gasket, which can effectively seal between the cylinder head and the cylinder block of an internal combustion engine Another objective of the present invention is to provide a cylinder head gasket for an internal combustion engine, which can effectively dissipate heat between the cylinder head components.

Brief description of the invention

The present invention relates to a gasket with a construction including polymer members attached with a metal strip for metering the lubricating oil through the openings in the metallic strip.

According to the present invention, there is provided, a cylinder head gasket to be disposed between a cylinder block and a cylinder head of the internal , combustion engine, comprising a gasket body formed with at least one" hole for a combustion chamber of the engine. The gasket has polymer members attached with a metal strip placed in coincidence with the lubricating oil passage formed between said cylinder block and cylinder head, such that the metal strip has a hole for metering the required amount of lubricating oil through said hole in the metallic strip.

The cylinder head gasket is put on the cylinder block and the cylinder head is fixedly secured through the gasket to the cylinder block by tightening the bolts inserted into the boltholes. In this assembled state, the distance between an end surface of the cylinder block and an end surface of the cylinder head is contacted by the surfaces of the gasket that forms a gas-tight seal. The gasket has protrusions in the planar surfaces of the polymer area and metallic strip for affecting the sealing between the cylinder head and cylinder block. The protruded portion of the gasket being compression deformed avoids the unevenness due to the layers of polymer and metallic strip. Also the protruded portions allows for forming a liquid tight sealing for the coolant passages passing through the cylinder block and the cylinder head of the internal combustion engine.
Brief description of the drawings

Figure 1 illustrates the cross sectional view of the engine assembly having embodiments according to the present invention.

Figure 2 illustrates the top view of the gasket according to the present invention
Figure 3 illustrates \he top view of the metal strip according to the present invention
Detailed description of the invention

A selected illustrative embodiment of the present invention will be now described with respect to the accompanying figures.

In Figure 1, the principal portion of the engine of the present invention is shown in cross-sectional view. As shown in this figure, the engine includes a crankcase 201, a cylinder block 202 connected to the crankcase 201, a cylinder head 203 to be connected to the cylinder block 202 and a cylinder head cover. These are clamped and fixed together via stud bolts and the like, thereby constituting the main structure of the engine 200.

The crankcase has a structure in which the half cases 204 & 205 are integrally connected to each other. The halves cases and are formed by dividing the crankcase into right 205 and left portions 204. In the crankcase, formed of the combined half cases and, a crankshaft is rotatable bearing 206 supported. A connecting rod 207 is attached to a crankpin of the crankshaft 208 via a bearing located at the large-end thereof. A piston 209 is pivotally attached to the small-end of the connecting rod 207 via a piston pin. In this
embodiment, there is provided one piston 209 and the engine 200 of the present invention is a single cylinder 4-cycle engine 200.

The engine 200 of this embodiment generally includes the structure described above.

However, the engine 200 further includes an inventive gasket according to the present invention. In the said engine construction 200 the gasket 301 is an important element in the lubrication circuit. The lubricating oil is transferred from the oil sump by an oil pump to various parts of the engine 200. Prominently the lubricating oil is transferred to cylinder head 203 and crankshaft 208. The oil path 304 to cylinder head 203 being present in the cylinder block 202, it is always filled up with the lubricating oil. As a result, there is excessive passage of oil to the cylinder head 203. To prevent this excessive passage of oil and to provide the right quantity of oil to the cylinder head 203, metering of oil is very much essential. Providing a small hole in the metallic portion 303 of the gasket 301 does this metering by covering the lubricating path in the cylinder block 202 and restricting the lubricating channel.

Figure 2 and Figure 3 illustrates present invention that relates broadly to a gasket 301 for sealing between the cylinder head 203 and block 202 of an internal combustion engine 200, and particularly to a gasket construction 301 including elastomeric members 302 attached to a bean shaped metal retainer 303 for sealing about the lubrication port openings of the engine 200. The present invention is directed towards a gasket 301 disposed between a cylinder block 202 and a cylinder head 203 of the internal combustion engine 200, comprising a gasket body formed with at least one hole 304 for a combustion chamber of the engine 200. The gasket 201 has polymer members attached with a bean shaped metal strip 303 placed incoincidance with the lubricating oil passage 304 formed between said cylinder block 202 and cylinder head 203, such that the metal strip 203 has a hole 304 for metering the required amount of lubricating oil through said hole in the metallic strip 203.

The cylinder head gasket 301 is put on the cylinder block 202 and the cylinder head 203 is fixedly secured through the gasket 301 to the cylinder block 202 by tightening the bolts inserted into the bolt holes 305. In this assembled state, the distance between an end surface of the cylinder block 202 and an end surface of the cylinder head 203 is contacted by both side surface of the gasket 301 that forms a gas-tight seal.

The pressurized lubrication oil is passed through the various parts of the internal combustion engine 200 such as crankcase 201 and cylinder block 202 and cylinder head 203. In order to effectively provide the lubrication for various parts, the oil flow has to be effectively metered and ensured that only required amount of the lubrication oil has delivered to the respective parts. In order to confirm the oil flow metering, the hole 304 provided in the bean shaped metallic strip 303 of the cylinder head gasket 301 is made around 1.1 to 1.4 mm, and thereby maintaining required level of lubrication at the respective parts of the internal combustion engine 200.The bean shaped metallic strip preferably made of stainless steel of a thickness lesser than that of fibre gasket is placed in the bean shaped cut-out provided in the gasket with a uniform clearance between outer profile of the metal strip & inner profile of gasket cut-out. A .polymer layer is formed on both sides of the edges of metallic strip & gasket.

Thus the gap between metallic strip & gasket is sealed to make it leak proof. The width of the polymer layer is approximately 1.5 mm.

The gasket 301 has protrusions in the planar surfaces of the polymer area and metallic strip 303 for affecting the sealing between the cylinder head 203 and cylinder block 202. The protruded portion of the gasket 301 being compression deformed avoids the linevenness due to the layers of polymer and metallic strip 303. Also the protruded portions allows for forming a liquid tight sealing for the coolant passages passing through the cylinder block 202 and the cylinder head 203 of the internal combustion engine 200. The gasket 301 is capable of providing sealing between the cylinder head 203 and the cylinder block 202 of an internal combustion engine 200, and also metering the lubricating oil through the opening 304 in the metallic strip 303, and hence reducing size of the engine 200 as well as the manufacturing cost of the engine 200. Part numbers associated with the drawings

200. Engine 202. Cylinder block
201. Crankcase 203. Cylinder head 204 & 205. Crankcase halves 207. Connecting rod 206. Bearing 208. Crankshaft 209. Piston 303. Metal retainer
301. Gasket 304. Lubrication hole
302. Elastomeric Members ,

Claims We claim:

1. A lubrication system for an internal combustion engine comprising of at cylinder head and a cylinder block characterised in that a sealing gasket is disposed between the said cylinder block and the said cylinder head wherein the said gasket is attached with a metal strip placed incoincidance with a lubricating oil passage formed between said cylinder block and said cylinder head.

2. The lubrication system for an internal combustion engine as claimed in claim 1, wherein the said metal strip has a hole having a diameter of 1.1 to 1.4mm for metering the required amount of lubricating oil through said hole in the metallic strip.

3. The lubrication system for an internal combustion engine as claimed in claim 1, wherein the said metallic strip is placed in a cut-out provided in the said sealing gasket with an uniform clearance between outer profile of the metal strip and inner profile of the said sealing gasket cut-out that is filled up by a polymer layer formed on both sides of the edges of the said metallic strip and the said sealing gasket.

4. The lubrication system for an internal combustion engine substantially described and illustrated with reference to the accompanying, drawings.