Claims:WE CLAIM:
1. An internal combustion engine (100) for a vehicle (10), comprising:
a crankcase (110);
a cover clutch (120) attached to the crankcase (110), the cover clutch (120) having an inner face along which oil travels in the crankcase (110), and an outer face having a plurality of fins (122); and
a cover (130) adapted to the outer face of the cover clutch (120), the cover (130) being configured for directing atmospheric air towards the fins (122) on the outer face of the cover clutch (120), thereby cooling the oil traveling along the inner face of the cover clutch (120).

2. The internal combustion engine (100) as claimed in claim 1, wherein the cover (130) comprises an outer face (130A) and an inner face (130B) disposed towards the outer face of the cover clutch (120).

3. The internal combustion engine (100) as claimed in claim 2, wherein the cover (130) comprises a skirting (132) extending inwardly in a vehicle width direction, from a periphery of the cover (130), such that the skirting (132) abuts the outer face of the cover clutch (120).

4. The internal combustion engine (100) as claimed in claim 3, wherein the skirting (132) comprises of a first slot (134) for allowing atmospheric air to be directed towards the fins (122), and a second slot (136) for allowing air passing over the plurality of fins (122) to be directed back into the atmosphere.

5. The internal combustion engine (100) as claimed in claim 4, wherein the first slot (134) and the second slot (136) are disposed diametrically opposite to each other.

6. The internal combustion engine (100) as claimed in claim 4, wherein the periphery of the cover (130) is flanged radially outwards along the first slot (134) and the second slot (136).

7. The internal combustion engine (100) as claimed in claim 1, wherein the cover clutch (120) is attached to a right-hand side or a left-hand side of the crankcase (110), in a vehicle front view.

8. The internal combustion engine (100) as claimed in claim 1, wherein the plurality of fins (122) extend longitudinally on the outer face of the cover clutch (120), in a vehicle front rear direction.

9. The internal combustion engine (100) as claimed in claim 1, wherein the cover (130) completely overlaps with the cover clutch (120), in a vehicle side view.

10. The internal combustion engine (100) as claimed in claim 1, wherein the cover (130) comprises a plurality of through-holes (138) on the periphery of the cover (130) configured for adapting the cover (130) to the cover clutch (120).
, Description:FIELD OF THE INVENTION
[001] The present invention relates to an internal combustion engine for a vehicle.

BACKGROUND OF THE INVENTION
[002] In conventional saddle type vehicles, engine oil temperature increases while trying to achieve improved engine performances such as higher acceleration. At higher temperatures, the oil tends to lose its characteristics. Higher oil temperatures affect the engine durability and lifetime of rotating components like gears and crankshaft, due to the failure of proper cooling and lubrication. Thus, it is desirable that engine oil temperatures are reduced and regulated.
[003] In the existing systems for cooling of the engine oil, an internal oil cooler (IOC) arrangement is installed in cover clutch side of the engine which reduces the oil temperature by increasing the engine oil contact area through an oil circulation path. In these systems, the heated engine oil is passed through IOC’s circulation path for cooling and then it is directed to the engine lubrication system through crankcase.
[004] For further aiding heat dissipation from the heated engine oil, fins are added on the cover clutch outer side to carry heat to the atmospheric air. By incorporating fins, air contact area is improved in cover clutch side which results into a better heat dissipation. Hence, fins reduce engine oil temperature. However, there still remains scope for further reduction of engine oil temperature as the cooling of heated oil using only fins is still not very efficient.
[005] An additional issue with addition of fins on the cover clutch side for increment in oil cooling, is that the hot air from the fins gets dissipated to the rider’s leg, thereby resulting in discomfort to the rider. Further, provision of fins on the cover clutch side also has an impact on the vehicle aesthetics. Further, provisions other than fins, such as fans or blowers for engine oil cooling are limited by vehicle layout constraints as packaging space in a saddle type vehicle is very limited. Also, as fans and blowers are generally powered devices, routing of their respective wiring in the vehicle layout remains a challenge.
[006] Thus, there is a need in the art for an internal combustion engine for a vehicle which addresses the aforementioned problems.

SUMMARY OF THE INVENTION
[007] In an aspect, the present invention is directed towards an internal combustion engine for a vehicle. The engine has a crankcase, and a cover clutch attached to the crankcase. The cover clutch has an inner face along which oil travels in the crankcase, and an outer face which has a plurality of fins. The engine further has a cover adapted to the outer face of the cover clutch. The cover is configured for directing atmospheric air towards the fins on the outer face of the cover clutch thereby cooling the oil traveling along the inner face of the cover clutch.
[008] In an embodiment of the invention, the cover has an outer face and an inner face disposed towards the outer face of the cover clutch.
[009] In another embodiment of the invention, the cover has a skirting extending inwardly in a vehicle width direction, from a periphery of the cover, such that the skirting abuts the outer face of the cover clutch.
[010] In a further embodiment of the invention, the skirting has a first slot for allowing atmospheric air to be directed towards the fins, and a second slot for allowing air passing over the plurality of fins to be directed back into the atmosphere. In an embodiment, the first slot and the second slot are disposed diametrically opposite to each other.
[011] In a further embodiment of the invention, the periphery of the cover is flanged radially outwards along the first slot and the second slot.
[012] In a further embodiment of the invention, the cover clutch is attached to a right-hand side or a left-hand side of the crankcase, in a vehicle front view.
[013] In a further embodiment of the invention, the plurality of fins extend longitudinally on the outer face of the cover clutch, in a vehicle front rear direction.
[014] In a further embodiment of the invention, the cover completely overlaps with the cover clutch, in a vehicle side view.
[015] In a further embodiment of the invention, the cover has a plurality of through-holes on the periphery of the cover configured for adapting the cover to the cover clutch.

BRIEF DESCRIPTION OF THE DRAWINGS
[016] Reference will be made to embodiments of the invention, examples of which may be illustrated in accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in context of these embodiments, it should be understood that it is not intended to limit the scope of the invention to these particular embodiments.
Figure 1 illustrates a left side view of an exemplary saddle type vehicle in accordance with an embodiment of the invention.
Figure 2 illustrates a right side perspective view of an internal combustion engine of a vehicle, in accordance with an embodiment of the invention.
Figure 3 illustrates an exploded perspective view of the internal combustion engine, in accordance with an embodiment of the invention.
Figure 4 illustrates a side view of the internal combustion engine, in accordance with an embodiment of the invention.
Figure 5 illustrates a side view of a cover, in accordance with an embodiment of the invention.
Figure 6a and 6b illustrate a front view and a perspective view of the cover respectively, in accordance with an embodiment of the invention.
Figure 7 illustrates an exploded view of the internal combustion engine with the cover, in accordance with an embodiment of the invention.
Figure 8 illustrates a top perspective view of the internal combustion engine, in accordance with an embodiment of the invention.
Figure 9 illustrates a top view of the internal combustion engine, in accordance with an embodiment of the invention.
Figure 10 illustrates temperature of the engine oil in the present invention as compared to temperature of engine oil in the prior art, in accordance with an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION
[017] The present invention relates to an internal combustion engine for a vehicle. More particularly, the present invention relates to an internal combustion engine for a saddle type vehicle.
[018] Figure 1 illustrates an exemplary saddle type vehicle 10, in accordance with an embodiment of the invention. The saddle type vehicle 10 comprises an IC engine 100 that is vertically disposed. In an embodiment, the IC engine 100 is a single-cylinder type IC engine. The saddle type vehicle 10 further comprises a front wheel 14, a rear wheel 16, a frame member (not shown), a seat 18 and a fuel tank 20. The frame member includes a head pipe 22, a main frame, rear down tubes, and seat rails (not shown). The head pipe 22 supports a steering shaft (not shown) and two telescopic front suspensions 26 (only one shown) attached to the steering shaft through a lower bracket (not shown). The two telescopic front suspensions 26 support the front wheel 14. The upper portion of the front wheel 14 is covered by a front fender 28 mounted to the lower portion of the telescopic front suspension 26 at the end of the steering shaft. A handlebar 30 is fixed to upper bracket not shown and can rotate to both sides. A head light 32, a visor guard (not shown) and instrument cluster (not shown) is arranged on an upper portion of the head pipe 22. The frame member comprises a down tube 44 that may be located in front of the IC engine 100 and extends slantingly downward from head pipe 22. The main frame of the frame member is located above the IC engine 100 and extends rearward from head pipe 22. The IC engine 100 is mounted at the front to the down tube 44 and a rear of the IC engine 100 is mounted at the rear portion of the main frame. In an embodiment, the IC engine 100 is mounted vertically, with a cylinder block extending vertically above a crankcase 110 (shown in Figure 2). In an alternative embodiment, the IC engine 100 is mounted horizontally with the cylinder block extending horizontally forwardly from the crankcase 110. In an embodiment, the cylinder block is disposed rearwardly of the down tube 44.
[019] The fuel tank 20 is mounted on the horizontal portion of the main frame. Seat rails are joined to main frame and extend rearward to support the seat 18. A rear swing arm 34 is connected to the frame member to swing vertically, and a rear wheel 16 is connected to rear end of the rear swing arm 34. Generally, the rear swing arm 34 is supported by a mono rear suspension 36 or through two suspensions 36 on either side of the saddle type vehicle 10 (as illustrated in the present embodiment). A taillight unit 33 is disposed at the end of the saddle type vehicle 10 and at the rear of the seat 18. A grab rail 37 is also provided on the rear of the seat rails. The rear wheel 16 arranged below seat 18 rotates by the driving force of the IC engine 100 transmitted through a chain drive (not shown) from the IC engine 100. A rear fender 38 is disposed above the rear wheel 16.
[020] Further, an exhaust pipe (not shown) of the vehicle 10 extends vertically downward from the IC engine 100 up to a point and then extends below the IC engine 100, longitudinally along the vehicle length before terminating in a muffler (not shown). The muffler is typically disposed adjoining the rear wheel 16.
[021] Figure 2 illustrates a right side perspective view of the IC engine 100 mounted on the saddle type vehicle 10. As illustrated in Figure 2, and further illustrated in Figure 3, the IC engine 100 has a cover clutch 120 attached to the crankcase 110. The cover clutch 120 is configured for supporting and covering a clutch assembly of the engine 100. In the embodiment depicted in Figure 2, the cover clutch 120 is disposed on a right hand side of the crankcase 110. In an alternative embodiment, the cover clutch 120 is disposed on a left hand side of the crankcase 110.
[022] The cover clutch 120 has an inner face (not shown) along which oil travels in the crankcase 110. The oil travelling along the inner face of the cover clutch 120 defines an internal arrangement wherein heated oil from the cylinder block is transmitted to the inner face of the cover clutch 120. Since an outer face of the cover clutch 120 is exposed to the atmosphere, as the vehicle moves, atmospheric air travels over the outer face of the clutch cover 120, thereby cooling the oil traveling along the inner face of the cover clutch 120. The cooled oil is then transmitted back into the crankcase 110.
[023] To further increase surface area on the outer face of the cover clutch 120 for aiding in heat transfer from the oil to the atmosphere, the outer face of the cover clutch 120 has a plurality of fins 122 that protrude outwardly from the outer face of the cover clutch 120. In an embodiment, the plurality of fins 122 extends longitudinally on the outer face of the cover clutch 120, in a vehicle front rear direction.
[024] To further aid in the heat transfer to ensure better cooling of the engine oil, as illustrated in Figure 3 and Figure 4, the engine 100 of the present invention has a cover 130 adapted to the outer face of the cover clutch 120. Herein, the cover 130 is configured for directing atmospheric air towards the fins 122 on the outer face of the cover clutch 120. The cover 130 ensures that more atmospheric air flows over the fins 122, thereby cooling the oil traveling along the inner face of the cover clutch 120. In the embodiment illustrated in Figure 4, the cover 130 completely overlaps with the cover clutch 120, in a vehicle side view.
[025] The cover 130 has an outer face 130A (shown in Figure 6a) and an inner face 130B (shown in Figure 6a). The inner face 130B is disposed towards the outer face of the cover clutch 120. As further illustrated in Figure 6a, the cover has 130 has a skirting 132 that extends inwardly in a vehicle width direction, from a periphery of the cover 130. As referenced in Figure 7, the skirting 132 abuts the outer face of the cover clutch 120.
[026] As illustrated in Figure 5 and further referenced in Figure 7, the cover 130 has a plurality of through-holes 138 on the periphery of the cover 130 configured for adapting the cover 130 to the cover clutch 120. The through-holes 138 receive fasteners which then pass on to corresponding through holes on the outer face of the cover clutch 120, thereby adapting the cover 130 on the cover clutch 120. In an embodiment, the cover 130 has two through-holes 138, disposed diametrically opposite to each other and hex-fasteners are used to adapt the cover 130 to the cover clutch 120. This allows for the cover 130 to be adapted to the cover clutch 120 without any design modifications.
[027] Reference is made to Figure 6a, Figure 6b and Figure 9, wherein the skirting 132 has a first slot 134 for allowing atmospheric air to be directed towards the fins 122, and a second slot 136 for allowing air passing over the plurality of fins 122 to be directed back into the atmosphere. In an embodiment, the first slot 134 and the second slot 136 are disposed diametrically opposite to each other. In this manner, a gap is defined between the cover 130 and the outer face of the cover clutch 120 through which air can travel while passing over the plurality of fins 122. The path of the air being directed towards the fins 122 through the first slot 134 and back into the atmosphere through the the second slot 136 has been illustrated in Figure 9. Such direction of the air over the fins 122 results in passing of more air over the fins 122 as compared to the fins 122 without the cover 130.
[028] As further illustrated in Figure 6b, and referenced in Figure 5, the periphery of the cover 130 is flanged radially outwards along the first slot 134 and the second slot 136. Such flanging allows for air to be directed in a concentrated manner over the fins 122 through the first slot 134 and back into the atmosphere through the second slot 136. Flanging at the second slot 136 also prevents air from the fins 122 to be dissipated towards foot of the rider.
[029] Figure 10 illustrates the reduction in engine oil temperatures (T2) in the present invention as compared to engine oil temperature (T1) in the prior art without the cover 130. As can be seen, T2