FIELD OF INVENTION

The present invention relates generally to a four cycle internal combustion engine and more particularly to the oil pump layout on the enclosed area of the cover clutch assembly.

BACKGROUND OF THE INVENTION

Four cycle internal combustion engine is a preferable option in automobile industry as the fuel efficiency of four cycle internal combustion engine is more than two cycle engine, but on the other side heat generation is more in case of four cycle internal combustion engine thus for smooth functioning of engine and to reduce the heat generation, by minimizing the friction, lubrication is required for the engine. Use of oil pump inside the crankcase is one such lubrication mechanism in which the oil pump is housed in the crank case from where the oil pump circulates the oil to required parts of engine. Generally in conventional engines, the oil pump is mounted on crankcase Left and is driven by means of a gear mounted on the crankshaft. A separate chamber is formed around the crankshaft to house the oil.

SUMMARY OF THE INVENTION

The present invention relates to a four cycle internal combustion engine comprising a cylinder head assembly, a transmission system, a centrifugal clutch coupling the engine output with the transmission system wherein, the said centrifugal clutch assembly having an output member and an input member, the output member having an output shaft having a drive gear fixed to the shaft wherein the drive gear provides input to the transmission system, a crank shaft assembly defining the clutch housing wherein the centrifugal clutch and said crank shaft assembly is transmitting the engine output to the centrifugal clutch through the said input member, the crank case defining a wet chamber for housing the crank shaft assembly, the centrifugal clutch and the transmission system and wherein the crankcase is formed of a crankcase left and a crankcase right and the centrifugal clutch and the transmission system are housed in the crankcase left and the crankshaft assembly is housed in the crankcase supported by the crank case right journal bearings and crankcase left journal bearings, a cover clutch assembly is provided to cover the crankcase left and an oil pump assembly is housed in the enclosed area of the cover clutch assembly, the oil pump assembly circulating the oil to the cylinder head assembly, the crankshaft assembly and the cover clutch assembly.

BRIEF DESCRIPTION OF DRAWINGS

The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are incorporated in and constitute embodiments of the invention, illustrate several aspects of the invention and together with a description of the embodiments serve to explain the principles of the invention and thus, are not limited of the present invention and a brief description of the drawings is as follows:

Figure 1 is the perspective view of the engine more particularly of the cover clutch of the engine assembly.

Figure 2 is the cross-sectional view of the engine and more particularly the location of the oil pump over the cover clutch of the engine.

Figure 3 is the perspective view of the enclosed area of the cover clutch and more particularly the location of the oil pump in the cover clutch.

Figure 4 is a cross-sectional view of the engine illustrating in detail an embodiment of invention.

Figure 5 is illustrating the pathway of oil circulation from oil pump housed in cover clutch of the engine.

DETAILED DESCRIPTION OF THE INVENTION

The embodiments disclosed below are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following detailed description. Rather, the embodiments are chosen and described so that others skilled in the art may utilize their teachings. The invention may have application to all types of two wheeled vehicles.

Figure 1 is depicting the left side view of the rear portion of a two wheeler, wherein the engine (111) supplies power to the wheel (106) through a wheel shaft connected through a transmission system covered under the cover sprocket (104) in the figure. Embodiment 110 is the cover clutch covering the crank case left, not shown in the figure, and the oil filter (107) for the oil pump is mounted on the right side of the cover clutch (107).

Figure 2 is the cross-sectional view of the engine and more particularly showing the main embodiments of the left side of the engine related to the present invention. The Crankcase (204) and the cover clutch (211), are surrounding all the embodiments of the engine assembly such as crank shaft (202) wherein the crankshaft is connected to the piston through a piston connecting road (217), centrifugal clutch (215), transmission system and oil pump (212) wherein the oil pump (212) is housed in cover clutch (211), wherein the transmission systems mainly includes centrifugal clutch (215) connected to the primary driven shaft (201) which is further connected to the drive sprocket (207) which transmits power to the sprocket wheel or driven sprocket (205).

Further referring to Figure 3 is the perspective view of the enclosed area of the cover clutch (304) wherein the oil pump (311) is housed over a mounting surface (307) and below the oil pump driven gear (306). Oil pump connecting shaft (314) engages the oil pump (311) and oil pump driven gear (306) wherein the said shaft connects the oil pump gear to the driving gear housed on the crank shaft, as shown in Figure 2, oil pump driven gear (217) is engaging oil pump (212) and the crank shaft (202) through oil pump driven gear (214).

Figure 4 is a cross-sectional view of the engine illustrating in detail an embodiment of invention wherein the oil pump (408) is housed in the cover clutch (405) wherein the oil pump is engaged with the crankshaft (401) through the oil pump drive gear (411) and oil pump driven gear (409). As soon as the crank shaft (401) rotates, oil pump drive gear (411) transmits torque to the oil pump driven gear (409) and hence the oil pump (408) starts working and circulates oil in the engine parts as shown in figure 5.

Oil from oil sump (501) goes to primary filter (502) and then enters through inlet port (503) (313 as shown in figure 3) in the oil pump (504) wherein the oil pump is housed in the cover clutch (304 as shown in figure 3). This process occurs as soon as the oil pump starts working as the suction force of oil pump enables it. Further, the oil pump pumps the oil to the secondary filter (507) (406 as shown in figure 4) wherein the secondary filter is housed in the cover clutch (304 as shown in figure 3), after filtration oil directly goes to the crank case left inlet (509) through the outlet port (312 as shown in figure 3) in the cover clutch (304 as shown in figure 3) and further the oil goes to cylinder head assembly (511) and crank shaft assembly (512).

While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof.

Further, the pathways described are not necessarily to be performed only in the sequence illustrated or each step only at the time indicated. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.

WHAT IS CLAIMED IS:

1) A four cycle engine comprising:

a) a cylinder head assembly;

b) a transmission system;

c) a centrifugal clutch coupling the engine output with the transmission system wherein, the said centrifugal clutch assembly having an output member and an input member;

d)a crank shaft assembly defining the clutch housing wherein, the centrifugal clutch is housed in the clutch housing;

e) a crank case defining a wet chamber for housing the crank shaft
assembly, the centrifugal clutch and the transmission system;

wherein, the crankcase comprising a crankcase left and a crankcase right; and

wherein, the centrifugal clutch and the transmission system is housed in the crankcase left;

f) a cover clutch assembly covering the crankcase left; and

g) an oil pump assembly housed in the enclosed area of the cover clutch assembly;

wherein, the oil pump assembly is configured to facilitate circulation of oil to the cylinder head assembly, the crankshaft assembly and the cover clutch assembly.

2) A four cycle engine, as claimed in claim 1, wherein the output member having an output shaft with a drive gear configured to provide input to the transmission system.

3) A four cycle engine, as claimed in claim 1, wherein the crank shaft assembly is transmitting the engine output to the centrifugal clutch.

4) A four cycle engine, as claimed in claim 1, wherein the crankshaft assembly is housed in the crankcase right and crankcase left.

5) A four cycle engine, as claimed in claim 4, wherein the crankcase right and the crankcase left are supported on a plurality of journal bearings.