Description:FIELD OF THE INVENTION
[001] The present invention generally relates to an internal combustion engine. More particularly, the present invention relates to a cooling arrangement of the internal combustion engine for a motor vehicle.
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BACKGROUND OF THE INVENTION
[002] Generally, in conventional motor vehicles, various rotary electrical machines such as an Integrated Starter Generator (ISG), which acts like both Starter motor and Generator are widely used. However, during the running of the ISG, a large amount of heat is generated in the ISG. Due to the high temperatures resulting from the heat generation, there is an efficiency loss in the functioning of the ISG, which leads to reduction in the torque generated by the ISG. The reduction in the generated torque leads to startability issues in the engine, since the generated torque may not be sufficient for cranking the engine. Thus, dedicated cooling arrangements are required to be made for the rotary electrical machines like the ISG.
[003] In conventional oil cooling arrangements for the ISG, an oil path is provided to ISG by creating an oil channel in a crankcase and a crankshaft of the engine. Oil from this oil channel is sprayed on to a stator part of the ISG. In such arrangements, a forced oil circulation arrangement is provided wherein pressurised oil is supplied to the crankshaft. Since, the crankshaft is connected to a rotor of the ISG, drill holes are provided on the crankshaft. Pressurised oil from the crankshaft exits through these drill holes and this pressured oil is sprayed towards the stator of the ISG, thereby cooling the ISG. However, provision of such an arrangement is extremely complex since oil needs to enter crankshaft from one side of the engine and then travel through to the other side of the engine via an oil pin, and for this, large channels are required to be provided in the crankshaft. In addition, special fasteners are required along with the drill holes. The long travel path of the oil also leads to loss in oil pressure, thereby reducing oil supply to the ISG, and hence reducing cooling performance.
[004] In alternative ISG cooling arrangements, a separate pipe line is created outside the engine from which the oil is transferred from right side crankcase oil pump to the ISG placed on the left side of the engine. However, provision of this separate pipeline involves complicated manufacturing process and introducing various new parts in engine thereby increasing engine overall weight. Usage of an external pipe also results in the external pipe being susceptible to damage and causing oil leakage.
[005] Thus, there is a need in the art for an internal combustion engine which addresses at least the aforementioned problems.

SUMMARY OF THE INVENTION
[006] In one aspect, the present invention is directed towards an internal combustion engine. The internal combustion engine has a crankcase having a first crankcase half and a second crankcase half placed adjoining each other. A cover member is placed adjoining the first crankcase half. A rotary electrical machine is housed in the cover member. A first channel is provided in the first crankcase half and the first channel is configured to receive cooling fluid from a fluid pump. A second channel is provided in the cover member. The second channel is configured to receive cooling fluid from the first channel and supply the cooling fluid to the rotary electrical machine for cooling the rotary electrical machine.
[007] In an embodiment of the invention, the internal combustion engine is provided with a gasket. The gasket is provided between the first crankcase half and the cover member. The gasket has a slot for allowing cooling fluid to pass from the first channel to the second channel. Further, the gasket has a shape and profile conforming to a shape and profile of the first crankcase half and the cover member.
[008] In another embodiment of the invention, the first crankcase half includes a left crankcase half and the second crankcase half includes a right crankcase half, in an engine rear view along a central engine axis.
[009] In a further embodiment of the invention, the rotary electrical machine is an integrated starter generator, and the integrated starter generator is housed in the cover member.
[010] In a further embodiment of the invention, the rotary electrical machine has a rotor and a stator, wherein the second channel is configured to supply cooling fluid to the stator of the rotary electrical machine.
[011] In a further embodiment of the invention, the cover member has a fluid jet opening. The fluid jet opening is configured to receive cooling fluid from the second channel and spray the cooling fluid on the stator of the rotary electrical machine.
[012] In a further embodiment of the invention, the internal combustion engine has an internal oil cooler configuration for cooling of the cooling fluid, wherein the first channel receives the cooling fluid from the fluid pump through the internal oil cooler configuration.
[013] In a further embodiment of the invention, the first crankcase half has a main channel and the main channel is provided for supplying oil to a countershaft bearing placed inside the first crankcase half.
[014] In a further embodiment of the invention, the first channel is configured to receive oil from the main channel for cooling the rotary electrical machine.

BRIEF DESCRIPTION OF THE DRAWINGS
[015] 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 perspective view of a crankcase of an internal combustion engine, in accordance with an embodiment of the present invention.
Figure 2 illustrates a perspective view of a cover member of the internal combustion engine, in accordance with an embodiment of the present invention.
Figure 3 illustrates a gasket of the internal combustion engine, in accordance with an embodiment of the present invention.
Figure 4 illustrates a top sectional view of the internal combustion engine, in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION
[016] The present invention relates to an internal combustion engine. The internal combustion engine of the present invention is typically used in a vehicle such as a two wheeled vehicle or two wheeled hybrid vehicle, or a three wheeled vehicle or three wheeled hybrid vehicle, or a four wheeled vehicle or four wheeled hybrid vehicle, or other multi-wheeled vehicles or other multi-wheeled hybrid vehicles as required. However, it should be understood that the internal combustion engine as illustrated may find its application in any non-automotive application using an internal combustion engine.
[017] Figure 1 illustrates a perspective view of an internal combustion engine 100 in accordance with an embodiment of the invention. As illustrated, the internal combustion engine 100 comprises a crankcase 110. The crankcase 110 houses components of the internal combustion engine 100 and has a first crankcase half 110A and a second crankcase half (not shown). The first crankcase half 110A and the second crankcase half are placed adjoining each other.
[018] As illustrated in Figure 2, the internal combustion engine 100 further comprises a cover member 120. The cover member 120 is placed adjoining the first crankcase half 110A. The cover member 120 is configured to enclose the space formed between the first crankcase half 110A and the cover member 120. In that, the cover member 120 has a shape and profile conforming with the shape and profile of the first crankcase half 110A. The internal combustion engine 100 further comprises a rotary electrical machine 140, and the rotary electrical machine 140 is housed in the cover member 120. Thus, the rotary electrical machine 140 is housed in the enclosed space formed by the cover member 120 and the first crankcase half 110A.
[019] Reference is made to Figure 1 and Figure 2, wherein as illustrated, to provide cooling for the rotary electrical machine 140, the internal combustion engine 100 has a first channel 112 and a second channel 122. Herein, the first channel 112 is provided in the first crankcase half 110A and the first channel 112 is configured to receive cooling fluid from a fluid pump (not shown) provided in the internal combustion engine 100. The second channel 122 is provided in the cover member 120, and the second channel 122 is configured to receive cooling fluid from the first channel 112. The second channel 122 is further configured to supply the cooling fluid received from the first channel 112, to the rotary electrical machine 140 for cooling of the rotary electrical machine 140. Thus, the cooling fluid is supplied to the rotary electrical machine 140 from the fluid pump through the first channel 112 in the first crankcase half 110A and the second channel 122 in the cover member 120. The cooling of the rotary electric machine 140 ensures proper functioning of the rotary electrical machine 140 and prevents exposure of the rotary electrical machine 140 to higher temperatures.
[020] In an embodiment, as referenced in Figure 3, the internal combustion engine 100 comprises a gasket 130. The gasket 130 is provided between the first crankcase half 110A and the cover member 120 for sealing the joint of the first crankcase half 110A and the cover member 120 and for sealing gaps between the crankcase half 110A and the cover member 120. The gasket 130 has a shape and profile conforming to a shape and profile of the first crankcase half 110A and the cover member 120. The gasket 130 is provided such that the gasket 130 allows transmission of cooling fluid from the first channel 112 in the first crankcase half 110A to the second channel 122 in the cover member 120 while arresting any leakages between the first channel 112 and the second channel 122. To facilitate this, the gasket 130 has a slot 132 for allowing cooling fluid to pass from the first channel 112 to the second channel 122. The slot 132 is aligned with the first channel 112 and the second channel 122, thus allowing passage of cooling fluid from the first channel 112 to the second channel 122, while not allowing leakage of cooling fluid.
[021] Reference is made to the embodiment depicted in Figure 4, wherein as illustrated, the first crankcase half 110A comprises a left crankcase half and the second crankcase half comprises a right crankcase half, in an engine rear view along a central engine axis (X-X’) extending in an engine front-rear direction. In the rear view, the first crankcase half 110A is disposed on a left side of the central engine axis (X-X’) and the second crankcase half is disposed on a right side of the central engine axis (X-X’). Accordingly, the cover member 120 is disposed adjoining the left crankcase half.
[022] As further depicted in Figure 4, in an embodiment, the rotary electrical machine 140 is an integrated starter generator, and the integrated starter generator is housed in the cover member 120. In an alternative embodiment, the rotary electrical machine is an alternator acting solely as a generator, or the rotary electrical machine is a magneto configured to supply power to spark plugs of the internal combustion engine 100. In the embodiment depicted in Figure 4, the rotary electrical machine 140 comprises a stator 142 and a rotor. The stator 142 is fixedly housed in the cover member 120 and a rotor is disposed radially inward from the stator 142. The rotor is operatively coupled to a crankshaft of the internal combustion engine 100, thus providing torque to the crankshaft when the rotary electrical machine 140 performs a starter function, and receiving torque from the crankshaft to generate electric power when the rotary electrical machine 140 performs a generator function. Particularly, the second channel 122 is configured to supply cooling fluid to the stator 142 of the rotary electrical machine 140, thus providing cooling fluid to the stator 142 of the rotary electrical machine 140 without hampering the functioning of the rotor.
[023] To ensure that the cooling fluid reaches maximum surface area on the stator 142, the cover member 120 comprises a fluid jet opening 124 (shown in Figure 2). The fluid jet opening 124 is configured to receive cooling fluid from the second channel 122 and spray the cooling fluid on the stator 142 of the rotary electrical machine 140.
[024] In an embodiment, the cooling fluid is an engine oil for lubricating and cooling of different parts of the internal combustion engine 100, and the fluid pump is an oil pump configured to pump oil from an oil sump to different parts of the internal combustion engine 100. In an embodiment, the internal combustion engine 100 comprises an internal oil cooler configuration for cooling of the cooling fluid before the cooling fluid is supplied for cooling the rotary electric machine. Herein, the first channel 112 receives the cooling fluid from the fluid pump through the internal oil cooler configuration. Thus, the circulating cooling fluid is cooled before being supplied to the various engine parts.
[025] In a further embodiment, the internal combustion engine 100 comprises a countershaft. The countershaft is operatively connected to the crankshaft and transmits the rotation of the countershaft to the transmission as per requirement. Further, the internal combustion engine 100 has a countershaft bearing configured to rotatably support the countershaft in the crankcase 110. In this embodiment, the first crankcase half 110A comprises a main channel and the main channel is provided for supplying oil to a countershaft bearing placed inside the first crankcase half 110A. In this embodiment, first channel 112 is configured to receive oil from the main channel for cooling the rotary electrical machine 140. Thus, the first channel 112 receives a portion of the oil that is travelling in the main gallery for lubrication and cooling of the countershaft bearing, and this portion of the oil is then supplied to the rotary electrical machine 140.
[026] Figure 4 illustrates the flow of oil to the rotary electrical machine 140. In operation, the oil pump extracts oil from the oil sump and transmits the oil towards the internal oil cooler configuration where the oil is cooled. Thereafter, the oil travels from the internal oil cooler configuration towards the main gallery for cooling and lubrication of various engine parts including the countershaft bearing. A portion of the oil travelling to the countershaft bearing is received by the first channel 112 provided in the first crankcase half 110A. The oil is transmitted to the second channel 122 in the cover member 120 via the slot 132 in the gasket 130. The oil in the second channel 122 is sprayed on to the stator 142 of the rotary electrical machine 140 through the fluid jet opening 124, where the heat generated by the rotary electrical machine 140 is transferred to the oil. The oil then travels from the stator 142 back to the oil sump, and the oil is then cooled through the internal oil cooler configuration to be supplied again to various parts of the internal combustion engine 100.
[027] Advantageously, in the present invention provides an internal combustion engine wherein the cooling fluid is supplied to the rotary electrical machine through a channel in the first crankcase half and a channel in the cover member. Adequate provision of the cooling fluid thus ensures that the temperature of the rotary electrical machine does not rise above operational temperatures, thus ensuring proper functioning of the rotary electrical machine. In particular, proper functioning and lower temperatures of the integrated starter generator ensures elimination of startability issues of the engine since torque produced by the integrated starter generator remains sufficiently high to start the engine under all conditions. Moreover, in engines where the integrated starter generator provides torque assist to the engine in conditions other than starting or where the integrated starter generator is used in an idle start stop system, where the heat generated is very high, the present invention ensures sufficient cooling for the integrated starter generator.
[028] Further, the present invention ensures that no complex crankshaft modifications are required for providing cooling fluid to the rotary electric machine, thus reducing engine complexity and increasing manufacturing ease. Furthermore, the present invention also eliminates the requirement of an external piping arrangement for supplying cooling fluid to the rotary electric machine, thus reducing part count, complexity, costs and reducing risk of oil leakage.
[029] While the present invention has been described with respect to certain embodiments, it will be apparent to those skilled in the art that various changes and modification may be made without departing from the scope of the invention as defined in the following claims.

List of Reference Numerals
100: Internal Combustion Engine
110: Crankcase
110A: First Crankcase Half
112: First Channel
120: Cover Member
122: Second Channel
130: Gasket
132: Slot
140: Rotary Electrical Machine
142: Stator
, Claims:1. An internal combustion engine (100), comprising:
a crankcase (110), the crankcase (110) having a first crankcase half (110A) and a second crankcase half placed adjoining each other;
a cover member (120), the cover member (120) placed adjoining the first crankcase half (110A);
a rotary electrical machine (140), the rotary electrical machine (140) being housed in the cover member (120); a first channel (112), the first channel (112) being provided in the first crankcase half (110A), the first channel (112) being configured to receive cooling fluid from a fluid pump; and
a second channel (122), the second channel (122) being provided in the cover member (120), and the second channel (122) being configured to receive cooling fluid from the first channel (112) and supply the cooling fluid to the rotary electrical machine (140) for cooling the rotary electrical machine (140).

2. The internal combustion engine (100) as claimed in claim 1 wherein the internal combustion engine (100) being provided with a gasket (130), the gasket (130) being provided between the first crankcase half (110A) and the cover member (120), the gasket (130) having a slot (132) for allowing cooling fluid to pass from the first channel (112) to the second channel (122), the gasket (130) having a shape and profile conforming to a shape and profile of the first crankcase half (110A) and the cover member (120).

3. The internal combustion engine (100) as claimed in claim 1, wherein the first crankcase half (110A) comprises a left crankcase half and the second crankcase half comprises a right crankcase half, in an engine rear view along a central engine axis (X-X’).

4. The internal combustion engine (100) as claimed in claim 1, wherein the rotary electrical machine (140) being an integrated starter generator, and the integrated starter generator being housed in the cover member (120).

5. The internal combustion engine (100) as claimed in claim 1, wherein the rotary electrical machine (140) comprises a rotor and a stator (142), wherein the second channel (122) being configured to supply cooling fluid to the stator (142) of the rotary electrical machine (140).

6. The internal combustion engine (100) as claimed in claim 5, wherein the cover member (120) comprises a fluid jet opening (124), the fluid jet opening (124) configured to receive cooling fluid from the second channel (122) and spray the cooling fluid on the stator (142) of the rotary electrical machine (140).

7. The internal combustion engine (100) as claimed in claim 1 wherein the internal combustion engine (100) comprising an internal oil cooler configuration for cooling of the cooling fluid, wherein the first channel (112) receiving the cooling fluid from the fluid pump through the internal oil cooler configuration.

8. The internal combustion engine (100) as claimed in claim 1, wherein the first crankcase half (110A) comprises a main channel, the main channel being provided for supplying oil to a countershaft bearing placed inside the first crankcase half (110A).

9. The internal combustion engine (100) as claimed in claim 8, wherein the first channel (112) being configured to receive oil from the main channel for cooling the rotary electrical machine (140).