TECHNICAL FIELD
[0001] The present subject matter relates generally to a swinging type power unit and more particularly, but not exclusively, to a swinging type power unit with forced-air cooling..
BACKGROUND
[0002] Generally, in an internal combustion engine, an air-fuel mixture is compressed in a cylinder when a piston is moving towards the top dead center (TDC) in a compression stroke. The compressed air-fuel mixture is combusted that forces the piston to move towards a bottom dead center (BDC). Moreover, the combustion of the air-fuel mixture results in generation of heat in the cylinder. Additionally, friction between various components of the IC engine also generates heat. Therefore, the heat generated is transferred to a cylinder block and cylinder head that are mounted outside the cylinder. The cylinder block comprises of plurality of cooling fins situated around the cylinder block for dissipating heat into the air. A camshaft is located on the cylinder head for . opening and closing plurality of valves present on the cylinder head. Lubricating oil is circulated in the IC engine for lubricating components.including the piston and the cylinder, a valve train, and plurality of gears present in the IC engine. The heat generated due to the combustion, and friction is transferred from the cylinder head to the cooling fins. Flow of air over the cooling fins helps in dissipating the heat into the air.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] The detailed description for an integrated sealing member, in conformity with the present subject matter, for a forced air cooling system in an internal combustion engine is described with reference to the accompanying figures. The same numbers are used throughout the drawings to refer like features and components of the present subject matter.
[0004] Fig. 1 illustrates a swinging type power unit, in accordance with an embodiment of the present subject matter.

[0005] Fig. 2 (a) illustrates a top perspective view of a power unit, in
accordance with an embodiment of the present subject matter.
[0006] Fig. 2 (b) illustrates a top perspective view of the power unit depicted
in Fig. 2 (a), depicting flow of air.
[0007] . Fig. 3 (a) illustrates an integrated sealing member, in accordance with
an embodiment of the present subject matter.
[0008] Fig. 3 (b) illustrates a top view of an integrated sealing member.
[0009] Fig. 3 (c) illustrates a side view of the integrated sealing member.
[00010] Fig. 3 (d) illustrates a side view of the integrated sealing member.
[00011] Fig. 3 (e) illustrates a cross-sectional view of the integrated sealing
member, in accordance with an embodiment.
[00012] Fig. 4 illustrates a cross-sectional view of a power unit, in
accordance with an embodiment of the present subject matter.
[00013] Fig. 5 is an exploded view of a power unit, in accordance with an
embodiment of the present subject matter.
DETAILED DESCRIPTION
[00014] Generally, in vehicles with an internal combustion (IC) engine, a forced cooling system is used for better cooling of the IC engine. Moreover, vehicles having a frame structure with a restricted airflow to the IC engine location require forced cooling system. For example, in a vehicle with a step-through frame assembly, a step-through passage is provided at an anterior portion of a seat and the power unit, for example IC engine, is swingably connected. Further, an under seat cover is present that restricts the flow of air onto the cooling fins. As, the IC engine is located below the seat. The vehicle layout is such that the IC engine is almost covered by various vehicle components like, an under-seat cover at the front, a left hand side, and a right hand side body panels on left side, and right side respectively.
[00015] Therefore, for cooling the IC engine, air is forcefully directed on to the IC engine. The forced air cooling system is installed for cooling the IC engine comprises of a cooling fan, which is driven by a crankshaft. A fan

cover/fan-housing radially encloses the cooling fan. Air enters axially into the fan-housing due to the suction of the cooling fan. A cooling cowl and a deflector form a closed structure (hereinafter referred to as 'cooling cowl assembly'). The cooling cowl assembly encloses at least a portion of the cylinder block and the cylinder head. The fan-housing connected to the cooling cowl directs the air into the cooling cowl. The air that enters into the cooling cowl passes through the surface area of cooling fins provided on the cylinder head and the cylinder block, thereby cooling the cylinder head, cylinder block, and the cooling oil. The air that passes through the cooling fans gets heated up due to heat transfer form cooling fins. The hot air is directed out of the cooling cowl through the deflector.
[00016] For efficient functioning of the IC engine, the sealing of the engine assembly should be leak proof. Typically, a cylinder .head-cover is positioned on the cylinder head for holding lubricating oil, by using a first beading. The first beading prevents any leakage of the lubricating oil. Additionally, a second beading is used to seal the cooling cowl assembly and the cylinder head joining portion to isolate the forced air from escaping the cooling cowl assembly. Additionally, a cam bore is available on some IC engines. Further, a cam bore-cover is used to seal the cam bore that acts as a stopper. The first beading, the second beading, and the cam bore sealing member used in the cooling system for forced air cooled IC engine are available in known art.
[00017] However, in an engine assembly with forced air cooling system, a leak may occur at any of the plurality of headings used on the codling system due to the presence of multiple components for sealing. Leakage of air affects the functional efficiency of the cooling system. This results in excessive heating of the IC engine parts that would affect the functioning of the IC engine. Material parameters of the IC engine parts would be varied due to excessive heating. The IC engine parts like piston rings used in a piston are prone to damage due to excess heating. Further, use of multiple sealing members in cooling system would increase a possibility of leak to occur.

[00018] Further, in the known art, assembly and disassembly of cooling system by using multiple sealing members makes the process complex and time consuming. Use of plurality of sealing members increases the part count of the system, and increasing the weight of the system. Furthermore, the assembly time of the IC engine increases due tp the use of plurality of sealing members.
[00019] Hence, an objective of present subject matter is to provide a swinging
type power unit. According to an aspect, an integrated sealing member is installed
on the power unit. According another aspect, the integrated sealing member is
used to seal the lubricating oil between a cylinder head-cover, and a cylinder
head. Yet another aspect is, the integrated sealing member enables sealing of air
flow at the cooling cowl assembly. Additional aspect is, the integrated sealing
member .seals the cam..hor£-opening ■.
[00020] Further, the integrated sealing member of the present subject matter seals the air flow between cylinder head and the cooling cowl assembly from . leaking. In forced air cooled system, a cooling fan enclosed by a fan-housing directs the air into the cooling cowl. The air in the cooling cowl passes through the surface area of the cooling fins. The heat from the cooling fins is dissipated through forced air. The proposed integrated sealing member seals the gap between the cylinder head, and the cylinder head-cover and the gap between the cylinder head, and the cooling cowl assembly.
[00021] In an embodiment, the integrated sealing member is having a continuous structure disposed around at least a portion of the power unit. The integrated sealing member takes the shape of the cylinder head. In an embodiment, the integrated sealing member includes a first portion, and a second portion. The first portion is disposed between the cylinder head, and the cylinder head-cover for sealing any gap therebetween. The second portion is disposed between the cylinder head-cover, and the cooling cowl assembly for sealing any gap therebetween. In an embodiment, the integrated sealing member includes a cam bore-cover for covering at least a portion of a cam bore opening provided on IC engines. In an embodiment, the integrated sealing structure is provided with

one or more rib(s) that enables sealing of cooling cowl assembly to the cylinder head more effectively. Further, the one or more rib(s) run along the surface of contact of the parts of the IC power unit. Additionally, in another embodiment of the subject matter, a the cam bore-cover has a semi-circular shape for covering at least a portion of a cam bore thereby acting as a stopper.
[00022] Therefore, the number of parts of the power unit is reduced, thereby reducing the weight of the system. Reduction in weight of the system improves fuel economy. Furthermore, the assembly time is reduced due to the reduction in number of sealing members. The integrated sealing member in an embodiment is made of non-rigid/elastic material. The use of an elastic material like rubber compensates for any distortions occurrence during the assembly process of the ..power uniLand.the. rih-design..restricts the.excessive expansion of the integrated sealing member.
[00023] The aforementioned and other advantages of the present subject matter would be described in greater detail in conjunction with the figures in the following description.
[00024] Fig. 1 illustrates a swinging type power unit, in accordance with an embodiment of the present subject matter. In an embodiment, the power unit 100 is swingable connected to a frame assembly of a two-wheeled vehicle. In an embodiment, the power unit 100 is forwardly inclined. The power unit 100 is installed with a forced air cooling assembly. A cooling fan (not shown) of the forced air cooling assembly is enclosed by a fan-housing 160, where both the cooling fan and the fan-housing 160 are mounted to the power unit 100. A crankshaft (not shown) drives the cooling fan. A cooling cowl 120 is connected to the fan-housing. A deflector 150 is connected to the cooling cowl 120. The cooling cowl 120 and the deflector 150 form a closed structure, hereafter referred to as a cooling cowl assembly 120, 150. The cooling cowl assembly 120, 150 covers at least a portion of a cylinder head 140 (shown in Fig. 4), and a cylinder block mounted to a crankcase 110; A cylinder head-cover 130 covers at least a portion of the cylinder head 140. The integrated sealing member 200 is

sandwiched between the cylinder head-cover 130, the cooling cowl assembly 120, 150, and between the cylinder head 140 and the cooling cowl. A variator cover 170 covers various power transmission gears, and the kick-start setup. [00025] Fig. 2 (a) illustrates a top perspective view of a portion of the power unit, in accordance with an embodiment of the present subject matter. Fig. 2 (b) illustrates a top view of the power unit 100 depicts in Fig. 2 (a). Further, Fig. 2 (b) depicts flow of air through the cooling cowl assembly 120, 150. A fan-housing 160 encloses a cooling fan (not shown). The cooling fan, which is radially enclosed by the fan-housing 110, has a vent for axially sucking air into the fan-housing 110. A cooling cowl 120 encloses at least a portion of a cylinder head 140, and a cylinder block (not shown). A cylinder head-cover 130 encloses at least a portion of the cylinder head 140. A deflector 150 encloses at least a portion of the cylinder block and the cylinder head 140. The integrated sealing member 200 is made of an elastic material like rubber. The integrated sealing member 200 is disposed between the cylinder head-cover 130 and the cylinder head 140 and between the cylinder head 140, and the cooling cowl assembly 120, 150. The integrated sealing member 200 is made of an elastic material to compensate any relative movements between the cylinder head-cover 130, the cooling cowl assembly 120, 150, and the cylinder head 140. Any gaps formed between the cylinder head-cover 130, the cooling cowl assembly 120, 150, and the cylinder head 140 and the cooling cowl are sealed by the integrated sealing member 200. Additionally, the integrated sealing member 200 covers the cam bore-cover 220 for sealing at least a portion of a cam bore (not shown). [00026] Air enters axially 180 into the fan-housing 160, which is sucked in by the cooling fan. The air from the fan-housing 160 thereby enters into the cooling cowl 120. The air flows through the cooling fins and heat transfer takes place. The hot air comes out 190 through an outlet present in the deflector 150. The integrated sealing member 200 prevents any air leakage that could occur at the joining portion of the cooling cowl assembly 120, 150, and the cylinder head 140, thereby sealing any gap therebetween. The integrated sealing member 200 has one or more rib(s), which provide a tight seal. Additionally use of

elastic/non-rigid material for integrated sealing member 200 improves the sealing. The IC power unit 100 is forced air cooled efficiently. [00027] Fig. 3 (a) illustrates a top perspective view of the integrated sealing member in accordance with the embodiment of the present subject matter. Fig. 3 (b) illustrates a top view of the integrated sealing member. Fig. 3 (c) is a side view of the integrated sealing member. Fig. 3 (d) illustrates another side view of the integrated sealing member. The integrated sealing member 200 is a continuous structure. The integrated sealing member 200 is adapted to extend along an upper periphery of the cylinder head 140, a lower periphery of the cylinder head-cover and the upper periphery surface of the cooling cowl assembly 120, 150. In an embodiment, the integrated sealing member 200 is provided with one or more rib(s) (shown in Fig. 3 (d)) that extend along the continuous structure. The one or more rib(s) improve sealing any gap therebetween. Further, the one or more rib(s) enables in reduction of excessive forces during assembly. Further, the one or more rib(s) enables reduction of damage of the integrated sealing member 200 by deformation. The one or more rib(s) are formed as protrusion(s) extending along the perimeter of the integrated sealing member 200.
[00028] In an embodiment, a cam bore-cover 220 covering at least a portion of the cam bore is illustrated as a part of the embodiment. The cam bore-cover 220, which is integrally formed on the integrated sealing member 200, covers at least a portion of a cam bore (not shown). Fig. 3 (d) depicts a side view of the integrated sealing member 200. The integrated sealing member 200 has one or more hole(s) 230 (shown in Fig. 3 (a)) through which the cylinder head-cover 130 is fastened to cylinder head 140, the cooling cowl assembly 120, 150 is secured to around the power unit 100 by plurality of fasteners. [00029] The integrated sealing member 200 having a continuous structure arranged around a periphery of the cylinder head 140, which is disposed between, a cylinder head 140, and a cylinder head-cover 130 and a cooling cowl assembly 120, 150, and the cylinder head 140 therebetween. As the integrated sealing

member 200 is arranged around the periphery of a cylinder head 140, it takes the shape of the cylinder head 140.
[00030] Fig. 3 (e) depicts the cross-sectional view taken along the axis X-X' as depicted in Fig. 3 (a). The sealing member comprises a first sealing portion 200A and a second portion 200B. In an embodiment, Further, the portion 200A, and the second portion 200B are integrally formed. In an embodiment, a horizontal offset is provided between the first portion 200A and the second portion 200B, which are integrally formed.
[00031] Further, the cylinder head 140 is disposed with the first portion 200A of an integrated sealing member 200 along at least a portion of a face(s) receiving the cylinder head-cover 130: A second portion 200B of the integrated sealing member 200 is disposed along at least a portion of the face(s) of the cylinder head receiving the cooling cowl assembly 120,150.
[00032] In an embodiment (as shown in Fig, 3 (e)) the integrated sealing member 200 includes a base member 205, a first protrusion 210 extending from the base member towards the cylinder head-cover 120, which is substantially orthogonally from the base member 205. Further, a second protrusion 215 extending from the base member 205 away from the cylinder head-cover 120, which is in a direction opposite to the direction of extension of the first protrusion 210. Furthermore, the base member 205, the first protrusion 210, and the second protrusion 215 are integrally formed.
[00033] Fig. 4 illustrates a cross-sectional view of a power unit, in accordance with an embodiment of the present subject matter. . In the embodiment, a cylinder head-cover 130 is enclosing at least a portion of the cylinder head 140. The cylinder head 140 comprises of a camshaft 510, and other valve train components (cross-section shown). An enlarged view cross-section of the swinging type power unit 100 illustrates the integrated sealing member 200, which is sandwiched between a lower peripheral surface of the cylinder head-cover 130 and the upper peripheral surface of the cylinder head 140. Additionally, the integrated sealing structure 200 is sandwiched between the

outer peripheral surface of the cylinder head 140 and the upper peripheral surface of the cooling cowl 120,150.
[00034] The integrated sealing member 200 enables sealing of the lubricating oil that is circulated between the cylinder head-cover and cylinder. Further, a cam bore-cover 220 enables in .stopping the camshaft 410 motion along an axis of the camshaft 410, wherein the camshaft 410 is functionally coupled to the valves 420 of the power train 100. Further, the integrated sealing member 200 enables sealing of air that is forced into the cowling assembly 120, 150 form leaking at the upper surface of the cooling cowl assembly 120, 150. Additionally, the assembly time of the power unit is reduced, as the number of parts is reduced. [00035] Fig. 5 depicts an exploded view of a power unit, in accordance with an embodiment of the present subject matter. The cylinder head 140 is mounted to a cylinder block 180 and the cylinder head 140 is mounted with a cylinder head-cover 120 enclosing at least a portion of the cylinder head 140. A cooling cowl assembly 120,150 enclosing at least a portion of the cylinder block 180 and at least a portion of the cylinder head 140.
[00036] The power unit 100 is provided with an integrated sealing member 200. The cylinder head 140 is disposed with the first portion 200A of an integrated sealing member 200 along at least a portion of a face(s) receiving the cylinder head-cover 130. A second portion 200B of the integrated sealing member 200 is disposed along at least a portion of the face(s) of the cylinder head receiving the cooling cowl assembly 120, 150. The integrated sealing member 200 being provided with plurality of fastening holes 230 formed on the base member of the integrated sealing member 200 for fastening the cylinder head-cover 120 to the cylinder head 140 through the integrated sealing member 200.
[00037] Many modifications and variations of the present subject matter are possible in the light of above disclosure. Therefore, within the scope of claims of the present subject matter, the present disclosure may be practiced other than as specifically described.

We claim:
1. A swinging type power unit (100) for a two-wheeled vehicle, said power unit
(100) comprising:
a cylinder head (140) mounted to a cylinder block (180);
a cylinder head-cover (120) mounted to said cylinder head (140) and
enclosing at least a portion of the cylinder head (140); and
a cooling cowl assembly (120,150) enclosing at least a portion of the cylinder
block (180) and at least a portion of the cylinder head (140),
wherein
the cylinder head (140) being disposed with a first portion (200A) of an
integrated sealing member (200) along at least a portion of face(s) of the
cylinder head (140) receiving the cylinder head-cover (120), and
a second portion (200B) of the integrated sealing member (200) being
disposed along at least a portion of face(s) of the cylinder head (140)
receiving the cooling cowl assembly (120,150).
2. The power unit (100) of claim 1, wherein said integrated sealing member (200) includes a base member (205), a first protrusion (210) extending from the base member (205) towards the cylinder head-cover (120), and a second protrusion (215) extending from the base member (205) away from the cylinder head-cover (120).
3. The power train (100) of claim 1 or claim 2, wherein the first portion (200A) of the integrated sealing member (200) being formed by a portion of the base member (205) and the first protrusion (210) for sealing lubricating oil circulating between the cylinder head (140) and the cylinder head cover (120), therebetween.
4. The power unit (100) of claim lor claim 2, wherein the second portion (200B) being formed by another portion of the base member (205) and the second protrusion (215) for sealing forced air circulating between the cylinder head (140) and the cooling cowl assembly (120,150).
5. The power unit (100) of claim 1, wherein the integrated sealing member (200) further includes a cam bore-cover (220) and said cam bore-cover (220)

being adapted to cover at least a portion of a cam bore provided on the cylinder head (140).
6. The power unit (100) of claim 1 and claim 3, wherein the first protrusion (210) is adapted to accommodate a groove provided on a face of the cylinder head-cover (120) being received by the cylinder head (140).
7. The power unit (100) of claim 1, wherein the integrated sealing member (200) being made of non-rigid material.
8. The power unit (100) of claim 1, wherein the integrated sealing member (200) being provided with plurality of fastening holes (230) formed on the integrated sealing member (200) for fastening the cylinder head-cover (120) to the cylinder head (140).
9. The power unit (100) of claim 1, wherein the cooling cowl assembly (120, 150) is secured around the integrated sealing member (200) and the cylinder head (140) through fasteners.
10. An integrated sealing member (200) adapted to work with a swinging type power unit (100) of a two-wheeled vehicle, said sealing member (200) comprising:
a base member (205);
a first protrusion (210) extending substantially orthogonally from the base member (205); and
a second protrusion (215) extending orthogonally from the base member (205) and in a direction opposite to the first protrusion (210), wherein
the first protrusion (210) and one portion of the base member (205) being adapted to seal lubricating disposed between a cylinder head (140) and a cylinder head-cover (120), and the second protrusion (215) and another portion of the base member (205) being adapted to seal forced air between the cylinder head (140) and a cooling cowl assembly (120,150).