CAMSHAFT SUPPORT AND CRANKCASE AIR VENT FOR AN ENGINE

Abstract

A cam support plate and an air venting cover plate for an internal combustion engine are provided along with a gasket to seal the oil passages between the cam support plate and the cam chest. The cam support plate provides a rigid, generally non flexing support for mounting one or more cam shafts and crankshafts for an internal combustion engine. The cam support plate also provides appropriate mounting and oil circulating paths as required by the engine. A cover plate is provided which is not decorative but rather functional, includes a number of chambers having chamber walls of varying depths to provide a labyrinth or serpentine like path for air to separate from the oil and vent to the outside atmosphere through a hole in the plate and or cover. Grooves or slots provided in the lower region of the chambers allow the oil separated from the air to drain back into the crankcase.

Description

TECHNICAL FIELD

The present invention relates to internal combustion engines and more particularly, relates to a support plate, cam cover and gasket system providing distortion free support for an engine's cam-shaft and crankshaft and oil pump while simultaneously providing an air vent for the engine crankcase to reduce excessive oil temperature, crankcase pressure, oil foaming and aeration

BACKGROUND INFORMATION

Internal combustion engines such as motorcycle engines, for example, typically have two or more cylinders and each cycle is synchronized with a camshaft. Each camshaft is supported at one end by the engine housing and at the other end by a support plate of some sort. An example of such an engine and arrangement of parts can be seen, for example, in U.S. Pat. No. 6,047,667 incorporated herein by reference.

In many instances, however, the support plate for the camshaft in such systems is either more decorative than anything and/or provides little support for the camshaft(s) and crankshaft. It has been found that a cam support plate (often called a cam plate) that is not rigid enough allows a shift or bending action often causing scoring or other damage to the oil pump. The lack of rigidity in the cam plate also adds to oil leaking by mating passages due to flexing of the cam plate in its central region in an area where oil seals or no seals at all are generally found.

An additional problem arises in internal combustion engines that utilize a sump oil passage located in the bottom region of the crankcase. In such systems, piston pressure on the down stroke is needed to help move the oil to the oil pump and then back to the reservoir (oil tank). Normally a neutral pressure or slight pressure in the crankcase from the pistons allows oil to drain from the top end of the engine to the crankcase. A significant problem arises as an engine's rpms or displacement increases in that as pressure increases in a closed compartment (generally termed crankcase), the crankcase remains pressurized on both strokes. At this point, the oil is not allowed to freely drain from the top end to the crankcase, which causes the oil to become super heated in the heads. As rpm's decrease the pressure in the crankcase also decreases and the super heated oil can drain into the crankcase. This super heated oil is then pushed to the oil pump on the piston's down stroke. Because of the excess heat in the engine oil, air is easily introduced into the oil and the oil becomes aerated. This aerated oil is pushed from the oil pump to the reservoir (oil tank). This aerated oil is then fed back into the engine via the oil pump, reducing lubricity and hydrology to the internal engine components.

SUMMARY

Accordingly, what is needed is an external cam support plate which provides significant rigidity for the camshaft(s) and crankshaft, which includes a cam plate cover that includes an air baffle path that houses a labyrinth of passages vented externally through the cam support plate and/or cam cover allowing air and oil to be separated. Pressure generated by the pistons cause the excess pressure in the crankcase to be vented to atmosphere or to the air cleaner backing plate for emission purposes. This in turn allows the oil to drain freely from the top end of the engine, keeping the oil cooler and more viscous. This cooler oil can be pushed to the pump and back to the reservoir (oil tank) while substantially reducing the amount of air and temperature in the oil.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features and advantages of the present invention will be better understood by reading the following detailed description, taken together with the drawings wherein:

FIG. 1 is left side perspective view of the camshaft support plate, sealing gaskets and air venting cover according to the present invention in position to be mounted to an engine;

FIG. 2 is right side perspective view of the camshaft support plate, sealing gaskets and air venting cover according to the present invention in position to be mounted to an engine;

FIG. 3 is an interior perspective view of the air venting cover according to the present invention;

FIG. 4 is an exterior perspective view of the air venting cover according to the present invention; and

FIG. 5 is a close up interior perspective view of the air venting cover according to the present invention illustrating a cover for the air vent labyrinth area.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention features a novel camshaft support and crankcase air vent including one or more gaskets 11, FIG. 1, a camshaft support plate 10 (also called cam plate), and an air venting cover 12 for use on an internal combustion engine 14 such as, for exemplary purposes only, a motorcycle engine. Although the present invention will be explained in connection with a motorcycle engine, this is not a limitation of the present invention as the invention may be utilized on many different types of internal combustion engines.

The cam plate 10 includes one or more openings 16 in which are mounted camshaft's and one or more openings 18 in which is supporting a crankshaft. Other openings, holes and channels are provided in the cam plate as necessary to fasten the cam plate 10 to the engine block and provide appropriate oil movement throughout the engine's crank case, as is well known in the art.

As shown in FIGS. 1 and 2, the cam plate 10 as a first thickness indicated generally by arrows 16 along a portion of the periphery of the cam plate as well as in the central region 18. The first thickness is typically in the range of 0.600″ to 1.000″ inches thick. The cam plate 10 is made out of a solid piece of aluminum which is machined as appropriate and necessary. The cam plate 10 also includes a portion having a second thickness 20 greater than the first thickness 16. In the preferred embodiments, the second thickness 20 is in the range of 0.900″ to 1.000″ inches thick.

In a similar fashion, the air venting cover 12 is machined out of a solid piece of aluminum although it could also be fabricated from two pieces of aluminum which joined together to perform the same function.

As shown in greater detail in FIG. 3, the air venting cover 12 includes an interior region 22 having a number of cavities which are sized and shaped to accommodate the needs of various engine sizes, as is well known in the art. One unique feature of the present invention includes a number of chambers 24a-24d which together form a elaborate labyrinth for allowing air to separate from the oil in the crankcase and vent to the atmosphere outside of the engine. Each chamber includes a wall 25 separating one chamber from the next. Each chamber wall 25 includes a first periphery region 28 which extends above or beyond a second periphery region 26. Thus, the recessed region 26 in each chamber wall 25 forms a serpentine or labyrinth air path 30, FIG. 5 in which air can separate from the oil and exit through a port or opening 32 to the atmosphere. In addition, each chamber 24 includes a cut out region 34 proximate the bottom of the chamber which allows the oil from which there has been separated, to drain back into the crankcase to be re-circulated. A thin cover plate 36 is provided to cover the chambers 24 and isolate them from the rest of the crankcase so that the air and oil can efficiently separate from one another.

As shown in FIG. 4, the air vent cover 12 includes an exterior surface 38 which although appears to the user to be simply decorative in nature to match other crankcase covers found on standard engines, actually disguised is the fact that in the interior of the cover, and innovative air and oil separator labyrinth is provided, therefore making it functional.

The present invention is not intended to be limited to a system or method which must satisfy one or more of any stated or implied object or feature of the invention and should not be limited to the preferred, exemplary, or primary embodiment(s) described herein. Modifications and substitutions by one of ordinary skill in the art are considered to be within the scope of the present invention, which is not to be limited except by the allowed claims and their legal equivalents.

Claims

1. Parts for an engine, said engine including an engine body having a crankshaft, at least one cam shaft, at least one oil pump and at least one oil path for circulating oil within said engine body, said engine parts comprising:

a cam support plate, configured for coupling to said engine body and for providing generally non-flexing support for said at least one cam shaft and said crankshaft; and

an engine cover, configured for coupling to said cam support plate, and including an engine oil/air separator region, coupled to said at least one oil path and to an area outside said engine body, for allowing oil to be separated from an oil/air mixture, for allowing said oil to drain into said engine body and for allowing said air separated from said engine oil to vent to an area outside said engine body.

2. The parts for an engine of claim 1, wherein said air separated from said engine oil is vented to outside atmosphere.

3. The parts for an engine of claim 1, wherein said air separated from said engine oil is vented to an air capture system.

4. The parts for an engine of claim 1, wherein said engine is an internal combustion engine.

5. The parts for an engine of claim 4, wherein said internal combustion engine is a motorcycle engine.

6. The parts for an engine of claim 1, further including a first gasket coupled between said cam support plate and said engine body and a second gasket coupled between said engine cam support plate and said engine cover.

7. The parts for an engine of claim 1, wherein said engine oil/air separator region includes an air/oil path in the form of a labyrinth.

8. The parts for an engine of claim 7, wherein said labyrinth includes at least one path for air to vent to atmosphere and at least one path for oil to drain from said engine oil/air separator region to a central region in said engine body to be pumped by said oil pump.

9. Parts for a motorcycle engine, said motorcycle engine including an engine body having at least one cam shaft, a crankshaft, at least one oil pump and at least one oil path for circulating oil within said engine body, said engine parts comprising:

a cam support plate, configured for coupling to said engine body and for providing generally non-flexing support for at least one cam shaft and said crankshaft;

an engine cover, configured for coupling to said cam support plate, and including an engine oil/air separator region, coupled to said at least one oil path and to an area outside said engine body, for allowing oil to be separated from an oil/air mixture, for allowing said oil to drain into said engine body and for allowing said air separated from said engine oil to vent to an area outside said engine body; and

a first gasket coupled between said cam support plate and said engine body and a second gasket coupled between said engine cam support plate and said engine cover.

10. The parts for an engine of claim 7, wherein said engine oil/air separator region includes an oil/air path in the form of a labyrinth.

11. The parts for an engine of claim 8, wherein said labyrinth includes at least one path for air to vent to atmosphere and at least one path for oil to drain from said engine oil/air separator region to a central region in said engine body to be pumped by said oil pump.

12. Parts for a motorcycle engine, said motorcycle engine including an engine body having at least one cam shaft, crankshaft, at least one oil pump and at least one oil path for circulating oil within said engine body, said engine parts comprising:

a cam support plate, configured for coupling to said engine body and for providing generally non-flexing support for said leased one cam shaft and crankshaft;

an engine cover, configured for coupling to said cam support plate, and including an engine oil/air separator region, coupled to said at least one oil path and to an area outside said engine body, for allowing oil to be separated from an oil/air mixture, for allowing said oil to drain into said engine body and for allowing said air separated from said engine oil to vent to an area outside said engine body, wherein said engine oil/air separator region includes an oil/air path in the form of a labyrinth, said labyrinth including at least one path for air to vent to atmosphere and at least one path for oil to drain from said engine oil/air separator region to a central region in said engine body to be pumped by said oil pump; and

a first gasket coupled between said cam support plate and said engine body and a second gasket coupled between said engine cam support plate and said engine cover.