Claims:We Claim:
1. A vehicle (100), having a frame assembly (FA), said frame assembly (FA) extends rearward, along a longitudinal axis (L-L’) of said vehicle (100), said vehicle (100) comprising:
an engine (106) supported on said frame assembly (FA), said engine (106) including
a crankcase RH, LH (208R, 208L),
a cylinder head (201) wherein said cylinder head (201) is attached to the front portion of a cylinder block (202), said cylinder block (202) is forwardly inclined,
a cylinder head cover (210), said cylinder head cover (210) is attached to the front portion of the cylinder head (201), and
a breather pipe (302), said breather pipe (302) is disposed on the cylinder head cover (210) making a predetermined angle Oc with the longitudinal axis (L-L’).
2. An engine (106) comprising:
a crankcase (208R, 208L),
a cylinder head (201) wherein said cylinder head (201) is attached to the front portion of a cylinder block (202), said cylinder block (202) is forwardly inclined,
a cylinder head cover (210), said cylinder head cover (210) is attached to the front portion of the cylinder head (201), and
a breather pipe (401, 302), said breather pipe (401, 302) is disposed on the cylinder head cover (210) making a predetermined angle Oc with the longitudinal axis (L-L’).
3. The vehicle (100) as claimed in claim 1 or claim 2, wherein said breather pipe (302) disposed on the top surface of the cylinder head cover (210), said breather pipe (302) is bend in an angular range Oa of 90 degree to 120 degree with respect the longitudinal axis L –L’ of the vehicle (100) when viewed from the top.
4. A vehicle (100), having a frame assembly (FA), said frame assembly (FA) extends rearward, along a longitudinal axis (L-L’) of said vehicle (100), said vehicle (100) comprising:
an engine (106) supported on said frame assembly (FA), said engine (106) including
a crankcase (208R, 208L),
a cylinder head (201) wherein said cylinder head (201) is attached to the front portion of a cylinder block (202), said cylinder block (202) is forwardly inclined,
a cylinder head cover (210), said cylinder head cover (210) is attached to the front portion of the cylinder head (201), and
a breather pipe (401), said breather pipe (401) is disposed on the cylinder head cover (210) making a predetermined angle Oc with the longitudinal axis (L-L’).
5. The vehicle (100) as claimed in claim 1, claim 2 or claim 4, wherein said breather pipe (302, 401) is bend in predetermined angular range Oc from 90 degree to 120 degree.
6. The vehicle (100) as claimed in claim 2 or claim 4, wherein said breather pipe (401) disposed on side surface of the cylinder head cover (210), said breather pipe (401) is bend in an angular range Oa of 0 degree to 45 degree with respect the longitudinal axis L –L’ of the vehicle (100) from viewed from the top.
7. The vehicle as claimed in claim 1, claim 2 or claim 4, wherein said breather tube (302, 401) is connected to the air filter assembly (301) through breather hose (303, 402), said breather tube (302, 401) configured to have downstream end (303c, 402c) and upstream end (303d, 402d).
8. The vehicle (100) as claimed in claim 1, claim 2 or claim 4, wherein said downstream end (303c, 402c) is connected to the breather tube (302, 401) and upstream end (303d, 402d) is connected to the air filter assembly (301), wherein a breather hose axis A-A’ is passing axially through the center of breather hose upstream end (303d, 402d).
9. The vehicle (100) as claimed in claim 1, claim 2 or claim 4, wherein said breather hose axis A-A’ makes a predetermined angle Ob with longitudinal axis L-L’ of the vehicle (100), said predetermined angular range Ob lies in between 45 degree to 180 degree in anticlockwise direction with respect to the longitudinal axis L-L’.
10. The vehicle (100) as claimed in claim 1, claim 2 or claim 4, wherein said breather hose (303, 402) configured to have plurality of bends (302a, 302b, 401a, 402b).
11. The vehicle (100) as claimed in claim 1, claim 2 or claim 4, wherein said air filter assembly (301) disposed on the side opposite to the exhaust system side.
12. The vehicle (100) as claimed in claim 1, claim 2 or claim 4, wherein said breather tube (302, 401) is disposed below a bracket (603), wherein said bracket (603) is attached to the frame assembly (FA).
13. The vehicle (100) as claimed in claim 1, claim 2 or claim 4, wherein said bracket (603) holding the electronic component (602) disposed below the seat assembly (115), said electronic component (602) includes the controller (602).
, Description:TECHNICAL FIELD
[0001] The present subject matter relates to multi-wheel vehicle. More particularly, the present subject matter relates to breathing system of the multi-wheel vehicle.

BACKGROUND
[0002] Conventionally, the saddle type vehicles are powered by an internal combustion (IC) engine. Most automotive vehicles presently in production utilize an internal combustion reciprocating piston engine operating under an Otto cycle. The internal combustion (IC) engine comprises a cylinder head, abutting a cylinder block to form a combustion chamber where the burning of air fuel mixture occurs. The forces generated due to combustion of air fuel mixture is transferred to a piston which is capable of reciprocating inside the cylinder block, and this reciprocating motion is transferred to rotary motion of the crankshaft through a connecting rod by the slider crank mechanism. To seal the combustion chamber each piston has an O-ring(s) fitted within an annular groove in a cylindrical side of the piston. During an intake stroke of the piston the crankshaft pulls the connecting rod downward to induce a vacuum within the combustion chamber. The induced vacuum pumps a charge through an inlet valve into the combustion chamber. On a compression cycle, the inlet valve is closed and the piston is pushed upward by the connecting rod providing a compression ratio. Upon ignition of the charge within the combustion chamber, the piston is pushed downward by the combustion energy. After combustion is virtually or totally complete, an exhaust valve opens and the crankshaft pushes the piston upwards to exhaust the charge and the cycle is then repeated.
[0003] During the compression and combustion cycles, very high gas pressure is experienced on the O-ring resulting in slight leakages of gas, often referred to as blow by. The blow by, which includes air, fuel, vapor and combustion by-products, increases the pressure within the engine block which is exposed to the oil pan. If the blow by is not relieved, it will force the oil in the oil pan to escape via the dip stick and the engine will thus lose lubrication. To prevent the loss of lubrication, the blow by is typically vented to the atmosphere which is not preferred as an environmental hazard. To overcome the above problem typically a positive crankcase ventilation at crankcase of engine is provided but it has inherent disadvantages like freezing of oil due to drop in temperature, hence there is need to have efficient positive crankcase ventilation system which will meet the common requirements of vehicle including low weight, low cost, high efficiency, good controllability throughout the entire speed range while overcoming all above problems & other problems of known art.

BRIEF DESCRIPTION OF THE DRAWINGS
[0004] The detailed description is described with reference to an embodiment of a two wheeled saddle type vehicle along with the accompanying figures. The same numbers are used throughout the drawings to reference like features and components.
[0005] Fig. 1 illustrates a left side view of an exemplary vehicle, as per first and second embodiment of the present invention.
[0006] Fig. 2 illustrates a top cut section view of engine with localized perspective view of cylinder head cover of the vehicle, as per the present invention.
[0007] Fig. 3a illustrates a top view of the engine with air filter assembly as per first embodiment of the present invention.
[0008] Fig. 3b illustrates a top view of the engine with air filter assembly as per second embodiment of the present invention.
[0009] Fig. 4 illustrates the side cut section view of the breather pipe as per present invention
[00010] Fig. 5 illustrates the graphical representation of the test results as per first and second embodiment of the present invention.
[00011] Fig. 6 illustrates a partial cut perspective view of the rear side of the vehicle and a localized view of the engine with the electronic component and battery pack as per first embodiment of the present invention.

DETAILED DESCRIPTION
[00012] Various features and embodiments of the present invention here will be discernible from the following further description thereof, set out hereunder. According to an embodiment, the prime mover is an internal combustion (IC) engine, said internal combustion (IC) engine described here operates in four cycles. Such an internal combustion (IC) engine is installed in a step through type two or three or multi wheeled vehicle. It is contemplated that the concepts of the present invention may be applied to other types of vehicles employing the similar systems within the spirit and scope of this invention. Also, the prime mover includes the traction motor and various other propelling means generally known in art. Further "front" and "rear", and "left" and "right" referred to in the ensuing description of the illustrated embodiment refer to front and rear, and left and right directions as seen from a rear portion of the two wheeled vehicle and looking forward. Furthermore, a longitudinal axis L – L’ unless otherwise mentioned, refers to a front to rear axis relative to the prime mover i.e. engine, while a lateral axis X – X’ unless otherwise mentioned, refers generally to a side to side, or left to right axis relative to the prime mover i.e. engine.
[00013] However, it is contemplated that the disclosure in the present invention may be applied to power train or engine without defeating the spirit of the present subject matter. The detailed explanation of the constitution of parts other than the present invention which constitutes an essential part has been omitted at suitable places.
[00014] Generally, in a saddle-wheeled vehicle with a step-through type, a step-through space is provided. The step-though space has a floorboard extending either side in the lateral direction X – X’ and may be used for carrying loads or for the rider to rest feet. In such vehicles, the frame structure starts from the head pipe, and extends downwards to the step-through space and again rises to form a driver seat, crosses a pillion seat and finishes at the rear lamp assembly. The IC engine is of horizontal type that is, a cylinder axis (the axis on which the piston of the IC engine reciprocates) is almost parallel to the central longitudinal axis of the two wheeled vehicles. Typically, the frame assembly acts as a skeleton for the vehicle that supports the vehicle loads. The IC engine is functionally connected to a rear wheel of the vehicle through means generally known in the arts such as by a sprocket and chain drive, which provides the forward motion to the vehicle.
[00015] As IC engine operates on four distinct piston strokes including intake (suction), compression, combustion (power) and exhaust to complete one operating cycle. During the compression and combustion cycles, very high gas pressure is experienced on the O-ring resulting in slight leakages of gas, often referred to as blow by, hence a positive crankcase ventilation system is provided in engine to allow the blows by gases to escape from crankcase. The positive crankcase ventilation hereinafter “PCV system” is typically employed to ventilate the crankcase and recirculate the blowby gas to the intake side of the engine for burning the gas in the combustion chamber. The PCV system takes advantage of the negative pressure in the intake to draw the gas out of the crankcase and may utilize a PCV valve to regulate the flow. In cold environments, a common concern is freezing of the water vapor component of the blowby gas in an external breather hose and valve. In order to address said issues it is known in the art to provide the PCV system on the crankcase of engine but crankcase ventilation system has inherent disadvantages like malfunction of system which causes the pressure in the crankcase to rise. The malfunction may be brought about by freezing of the oil in the breather hoses or breather tubes caused by a drop-in temperature by being exposed to external cooling. The PCV system malfunction may also be caused by production tolerances and/or assembly variability of components in the PCV system, giving rise to increased crankcase pressure. The elevated pressure in the crankcase may further lead to component degradation leading to poor durability & reliability of the engine.
[00016] To overcome the above problem i.e. having PCV system at crankcase of engine, in known art a PCV system is configured on the cylinder head cover of the engine which is near to the heating zone i.e. combustion chamber and prevent the condensation of oil and water vapour in breather hose to the intake system. While such solution may be viable for an IC engine, it often leads to increase in size of the IC engine making it cumbersome to packaging in a vehicle. The challenge of such compact packaging & small engine design is further complex for a hybrid powertrain system especially in terms of the need to package in compact space. dwindling fuel sources is pushing electric vehicles into focus. Still comparable performance to the energy density of a full tank of gasoline to the full charge battery is limited. Therefore, hybrid vehicles provide possible solution that combine the power of gasoline and electricity for propulsion but bring along the challenge of necessitating a compact powertrain within the same overall size of the vehicle.
[00017] Typically, the current hybrid layouts have engine which run on the higher temperature as the space available for fresh air entry inside cooling system of engine and for easy escape of hot air in environment is very less. The air which is feed to the engine is passed over from many vehicle components before it gets enter to the engine cooling system. These components include battery pack which is generally mounted in a space which is exposed to the natural cooling through incoming air and at the same time in a position to maintain optimum centre of gravity of the vehicle to maintain vehicle dynamics and ergonomics. Hence it preferred to have battery pack on the floor board of vehicle. But plurality of batteries emits heat due to chemical reaction inside. Further, there is an electronic component like controller which emits heat to the nearby air as its works continuously controlling motor, battery and engine electrical components. Thus, the ambient hot air over engine is not able to escape soon as engine is having the electronic component like controller at its front top, the utility box at top and style panel from left hand side and right-hand side. This heated air instead of escaping completely to the environment, some amounts of hot air enter into the engine cooling system causing decrease in engine cooling efficiency. This results in higher engine temperature causing more pressure inside the crankcase and over cylinder head cover empty space. This results in more oil fumes to escape and settle in drain tube of the air filter assembly and ultimately decreases the quantity of engine oil inside engine. With the decrease in engine oil, engine parts will get more heated due to lack of lubrication oil, as engine oil helps engine for both cooling as well as lubrication. This heated part will further increase the temperature of engine. Also, the serviceability time of engine air filter will decrease as the oil drain tube of the air filter assembly which is assembled outside air filter assembly to collect separated oil from oil fumes, need to be clean more frequently which may be less than about e.g. 1500~2000km. Thus, a chain reaction leads to cascading adverse effect on the crankcase ventilation which is highly undesirable.
[00018] Further, introducing a breathing system in compact layout and small sized vehicles is always a challenge for the automobile manufactures to achieve best engine performance. As it is challenging in view of the adverse impacts viz. size, layout, cost, weight, number of parts to accommodate the additional components such as clutch, gear trains and one-way clutches. Further the change in existing designs of cylinder head/ cylinder block leads to increase in the size of the engine and modifying the existing design leads to more cost to due complex machinability of intrinsic parts.
[00019] Therefore, for best vehicle performance and optimal operating conditions, to transmit power from the prime mover to rear wheel of the vehicle the critical issues involved in the design of the breathing system are to consider improving efficiency, better operability and reduce oil losses, enable improved positive crankcase ventilation and at the same time retain its attractive features of low cost and easy drivability.
[00020] Hence, an improved breathing system is proposed in the present subject matter in order to alleviate one or more drawbacks highlighted above & other problems of known art.
[00021] It is therefore an object of the present invention to provide the breathing system for the multi wheel vehicle, which is capable of overcoming the above-mentioned problems and other problems known in the art.
[00022] It is object of the invention to provide breathing system which reduces the oil content in the air filter assembly.
[00023] It is another object of the invention to provide the breather hose assembly which results in less wear and avoids premature aging.
[00024] It is yet another object of the present invention to provide the breathing system which is compact in size and does not foul with other parts & enables a compact engine layout.
[00025] It is object of the present invention to provide the breathing system which provides the efficient breathing.
[00026] To overcome the above stated problem a breather pipe is press fitted at cylinder head cover. The cylinder head cover has encasted maze inside which fumes travels before exiting from it. The breather pipe is connected to the air filter assembly through a breather hose. The breather pipe is bend at predetermined angle Oc which is away from the exhaust system of engine. The bend will decrease more fumes temperature as the vapor pressure drop and liquid pressure drop will be more with the predetermined bend. Furthermore, the breather hose configured to have upstream end and downstream end. The breather pipe is connected to the downstream end of the breather hose in predetermined angular range Oa of 90 degree to 120 degree with respect the longitudinal axis L –L’. The predetermined angular range assures the higher temperature drop as the vapour pressure drop and liquid pressure drop. Moreover, the upstream end of the breather hose is connected to the air filter assembly at its right-hand side bottom. A breather hose axis A-A’ is passing axially through the center of the breather hose. Particularly, it passes axially through the center of breather hose upstream end. The breather hose axis A-A’ makes a predetermined angle Ob with longitudinal axis L-L’ of the vehicle. The predetermined angular range Ob lies in between 45 degree to 180 degree in anticlockwise direction with respect to the longitudinal axis L-L’. Further, the breather hose configured to have plurality of bends. Because of above breathing system the higher pressure at the bend zone will also decrease the velocity of fumes escaping from the breather pipe. Also, frictional losses to flow and bending losses will decrease the mass flow rate of fumes and will help in separating more engine oil from fumes and prevent oil accumulation inside air filter.
[00027] The aforesaid and other advantages of the present subject matter would be described in greater detail in conjunction with the figures in the following description with an embodiment of a two wheeled vehicle and its powertrain.
[00028] Figure 1. Illustrates a left side view of a two-wheeled vehicle (100) typically called a scooter, in accordance with an embodiment of the present subject matter. A frontward direction is indicated by an arrow F, and a rearward direction indicated by an arrow R provided in the top center of first figure. The vehicle is extending from the front direction to the rear direction along the vehicle longitudinal axis (L-L’). In an embodiment; the two-wheeled vehicle (100) of the present subject matter comprises a frame which is conventionally an under-bone chassis frame which provides a generally open central area to permit “step-through” mounting by a rider. The vehicle (100) illustrated, has a step-through type frame assembly (FA). The step-through type frame assembly (FA) includes a head tube (103), a down tube (104) and a sub frame (105). The frame assembly (FA) extends from a front portion F to rear portion R of the vehicle. Further, the frame assembly (FA) extends downward from the anterior portion of the head tube (103) and then extends to a rear portion of the vehicle (100) in inclined manner. The pair of side-tubes (not shown) extends rearwardly from the other end of the main tube (not shown) and supports vehicular systems such as a seat assembly (115), fuel tank assembly (not shown), a utility box (not shown) and a pillion hand rest (122). In the rear end of the two wheeled vehicle (100) a rear lamp assembly (119) and a rear mud-guard/rear fender (116) is provided. The rear guard (116) having deflector (113). The head tube (103) supports a steering tube (not shown) and further connected to the front suspension system (117) at the lower end. A handlebar support member (not shown) is connected to an upper end of the steering tube and supports a handlebar assembly (121) which is having a mirror (124). Two telescopic front suspension systems (117) (only one is shown) support a front wheel (120). The upper portion of the front wheel (120) is covered by a front fender (112) mounted to the lower portion of the steering shaft. There is a front brake (not shown) and a rear brake (not shown) arranged on the front wheel (120) and a rear wheel (108) respectively. The rear wheel (108) is supported towards the rear side of the frame assembly (FA) by an internal combustion (IC) engine (106) which is horizontally coupled swingably to the rear of the frame assembly (FA) of the two wheeled vehicle (100) through a rear suspension system (118). A traction motor (107) integrated to a rear wheel (108). In a preferred embodiment, the traction motor (107) is hub mounted on the rear wheel (108). An on-board battery (as shown in fig. 6) drives the traction motor (107). The internal combustion (IC) engine (106) is mounted on a swing arm (123), which is swingably connected to the down tube (104) using a toggle link. The frame assembly (FA) is covered by plurality of body panels, mounted on the frame assembly (FA) and covering the frame assembly (FA), including a front panel (102), a leg shield (109), an under-seat cover (110), and a left and a right-side panel (111). A glove box may be mounted to a leg shield (109). Over the rear wheel (108) a body panel is disposed to support the seat assembly (115). The internal combustion (IC) engine (106) transfers the drive to the rear wheel (108) as it is coupled to it. The internal combustion (IC) engine (106) comprises a transmission system, said system disposed leftward of the internal combustion (IC) engine (106) in the vehicle width direction.
[00029] A front fender (112) is covering the front wheel (120). A floorboard (114) is provided at the step-through space provide above the down tube (104). A seat assembly (115) is mounted to the sub frame (105). A utility box (not shown) is disposed below the seat assembly (115). A fuel tank (not shown) is positioned below the utility box. A rear fender (116) is covering at least a portion of the rear wheel (108) and it is positioned below the fuel tank (not shown). A reflector (113) is disposed on the rear fender (116). One or more rear suspension(s) (118) are provided in the rear portion of the vehicle (100) for comfortable ride. The vehicle (100) comprises of plurality of electrical and electronic components including a headlight (101), a rear lamp assembly (119), a transistor-controlled ignition (TCI) unit (not shown), a starter motor (not shown).
[00030] Figure 2 illustrates the top cut section view of the present embodiment where it represents the crankcase (208R, 208L) in which transmission assembly is present which extends rightward (RH) and leftward (LH) in the internal combustion engine (106) lateral direction (X-X’). The crankcase (208R, 208 L) comprising of a top surface, and a bottom surface, and a plurality of side surfaces of the crankcase, wherein the side surfaces are substantially vertical and configured to extend between the top surface and the bottom surface. The part extended in rightward (RH) direction is known as a crankcase RH (208R) and the part extended in leftward (LH) direction is known as a crankcase LH (208L). Similar to the crankcase (RH, LH), a crankshaft (205) also extends rightward (RH) and leftward (LH) in the internal combustion (IC) engine (106) lateral direction (X-X’). This extension results in two parts of the drive shaft (205)/crankshaft (205), first one is known as a crankshaft RH (205R) as the crankshaft extends in rightward (RH) direction and second one is known as a crankshaft LH as the crankshaft (205L) extends in leftward (LH) direction. The crankcase LH (208) is covered by housing (not shown). This housing makes the system leak proof and enables effective lubrication. In the crankcase LH (208L), of horizontally disposed internal combustion engine (IC) engine (106) such as that of scooter-type two-wheeled vehicles (100), an oil sump (not shown) is provided in the bottom-side of the crankcase LH (208L) for continuous lubrication and cooling of a piston (203) and a plurality of cylinder wall (203W), piston rings like oil ring (203O) and other parts of the internal combustion (IC) engine (106). The lubrication and cooling of the piston (203), the plurality of cylinder wall (203W), piston oil ring (203O) and other parts of the internal combustion (IC) engine (106) begins once an operation cycle of thermal energy conversion into mechanical energy begins. Once the operation cycle starts, rotation of the crankshaft (205) also starts. The cylinder head (201) is covered by the cylinder head cover (210) during operation of the internal combustion (IC) engine (106), the burning of air fuel mixture occurs in the cylinder block (202) where spark is provided with spark plug (206) mounted in cylinder head (201). The cylinder block (202) having fins (207) on outer surface for naturally cooling, as it provides additional surface area for air to pass over cylinder block (202). The forces generated due to combustion of air fuel mixture is transferred to a piston (203) which is capable of reciprocating inside the cylinder block (202) and this reciprocating motion is transferred to rotary motion of the crankshaft (205) though a connecting rod (204) by the slider crank mechanism. Further, as per the internal combustion engine (IC) engine (106) construction, on the crankshaft LH (205L) a gear oil pump drive (GOPD) (not shown) is mounted and the gear oil pump drive (GOPD) (not shown) are mated with an oil pump assembly (not shown). Due to that rotation of the crankshaft (205), the gear oil pump drive (GOPD)(not shown) also starts rotating, since the gear oil pump drive (not shown)is in contact with the oil pump assembly(not shown) which results in the movement of lubricant oil from oil sump(not shown) to lubricate and cool the piston(203), the plurality of piston cylinder wall(203W), overhead camshaft (211), bearings (213), cam chain (212) and other parts of the internal combustion (IC) engine(106) through the oil path (209) defined. During the compression and combustion cycles, very high gas pressure is experienced on the O-ring (203O) resulting in slight leakages of gas (as shown in figure encircled), often referred to as blow by. The blow by gases and heated air inside crankcase RH (208R) flow out from the plug oil hole (209P) inside crankcase RH (208R) along with lubrication oil which is pumped by the oil pump assembly (not shown) assembled in the crankcase LH (208L). From crankcase RH (208R) having predefined oil path (209) blow by gases and heated air along with oil reaches to the cylinder head (201) via cylinder block (202). Above cylinder head (201), cylinder head cover (210) is attached in order to form close loop of oil lubrication inside engine (106). The air heated fumes carry oil droplets with them when they exit from cylinder head cover (210). As per an aspect of the present invention, the cylinder head cover (210) is configured with an encasted maze (214) inside which fumes travels before exiting from it. This maze (214) reduces the velocity of the fume and thereby help in separating the oil from the air. The separated oil travels back to the crankcase (208R, 208L) from LH side of the engine (106) after lubricating cam chain (212) and cam shaft (211) of the engine (106). There after it gets filtered at the lowest position of the engine (106) by the oil filter (not shown) before again being suck by oil pump assembly (not shown).
[00031] Figure 3a illustrates the top view of the engine (106) connected to the air filter assembly (301) through breather hose (303) as per first embodiment of the present invention. The cylinder head cover (210) is provided with the breather pipe (302). The breather pipe is press fitted at the top of the cylinder head cover (210). The breather pipe (302) is connected to the air filter assembly (301) through breather hose (303). The breather hose (303) configured to have downstream end (303c) and upstream end (303d). The downstream end (303c) is connected to the breather tube (302) and upstream end (303d) is connected to the air filter assembly (301). The breather pipe (302) is connected to the downstream end (303c) of the breather hose (303) in predetermined angular range Oa of 90 degree to 120 degree with respect the longitudinal axis L –L’. The predetermined angular range assures the higher temperature drop as the vapour pressure drop and liquid pressure drop. the angle outside the predetermined range will be redundant as it will adversely affect efficient ventilation. Moreover, any such angle will position breather pipe (302) close to the exhaust system leading to adverse heating. Thus, predetermined angular range Oa positions the breather system away from the exhaust system of the engine (106). The breather hose (303) configured to have at least two bends (303a, 303b). The upstream end (303d) of the breather hose (303) is connected to the air filter assembly (301) at its right-hand side bottom. A breather hose axis A-A’ is passing axially through the center of the breather hose (303). Particularly, it passes axially through the center of breather hose upstream end (303d). The breather hose axis A-A’ makes a predetermined angle Ob with longitudinal axis L-L’ of the vehicle (100). The predetermined angular range Ob lies in between 45 degree to 180 degree in anticlockwise direction with respect to the longitudinal axis L-L’ of the vehicle (100). This predetermined angular range assures the ease of serviceability and avoids fouling with neighboring parts. Furthermore, the angular range outside the predetermined range will increase the assembly time and will allow flow back of oil easily when air filter assembly (301) is filled with the oil. Hence to avoid such peculiar situation it is designed to mount the upstream end (303d) of breather hose (303) in predetermined range Ob. Further, the air filter assembly (301) configured to have plurality of mazes (not shown). Hence the oil is further passing through the mazes inside the air filter assembly (301), so as to separate all oil from fumes before being feed inside the engine (106). The separated oil is collected at the front drain tube (307) of air filter assembly (301) while the air is passed over pre and post filter before being feed inside the combustion chamber of the engine (106).
[00032] Figure 3b illustrates the top view of the engine (106) connected to the air filter assembly (301) through breather hose (402) as per second embodiment of the present invention. The cylinder head cover (210) is provided with the breather pipe (401). The breather pipe (401) is press fitted at the side surface of the cylinder head cover (210). The breather pipe (401) is connected to the air filter assembly (301) through breather hose (402). The breather hose (402) configured to have downstream end (402c) and upstream end (402d). The downstream end (402c) is connected to the breather tube (401) and upstream end (402d) is connected to the air filter assembly (301). The breather pipe (401) is connected to the downstream end (402c) of the breather hose (402) in predetermined angular range Oa of 0 degree to 45 degree with respect the longitudinal axis L –L’ of the vehicle (100). The predetermined angular range assures the higher temperature drop as the vapour pressure drop and liquid pressure drop. the angle outside the predetermined range Oa will make breathing system redundant as it will adversely affect the efficient ventilation and position such that it will foul with neighboring parts and also increase the length of breather hose (402) Moreover it also reduces the required bend loss for optimum operating conditions. Thus, present breathing system positions the breather pipe (401) away from the exhaust system of the engine (106). Furthermore, the breather hose (402) configured to have at least two bends (402a, 402b). The upstream end (402d) of the breather hose (402) is connected to the air filter assembly (301) at its RH bottom. A breather hose axis A-A’ is passing axially through the center of the breather hose (402). Particularly, it passes axially through the center of breather hose upstream end (402d). The breather hose axis A-A’ makes a predetermined angle Ob with longitudinal axis L-L’ of the vehicle (100). The predetermined angular range Ob lies in between 45 degree to 180 degree in anticlockwise direction with respect to the longitudinal axis L-L’ of the vehicle (100). This predetermined angular range assures the ease of serviceability and avoids fouling with neighboring parts. Furthermore, the angular range outside the predetermined range will increase the assembly time and will allow flow back of oil easily when air filter assembly (301) is filled with the oil. Hence to avoid such peculiar situation it is designed to mount the upstream end (303d) of breather hose (303) in predetermined range Ob. Further, the air filter assembly (301) configured to have plurality of mazes (not shown). Hence the oil is further passing through the mazes inside the air filter assembly (301), so as to separate all oil from fumes before being feed inside the engine (106). The separated oil is get collected at the front drain tube (307) of air filter assembly (301) while the air is passed over pre and post filter before being feed inside the combustion chamber of the engine (106).
[00033] Figure 4 illustrates the breather pipe (302, 401) side cut section view. The breather pipe (302, 401) which is mounted over the cylinder head cover (210). The breather pipe (302, 401) is bend in angular range Oc of 90 degree to 120 degree of the vehicle (100) and away from the exhaust side of the engine (106). The bend in specified angular range Oc in breather pipe (302, 401) will help in reducing the flow velocity of the fumes as the pressure gets increase at the bend of the breather pipe (302, 401). The frictional head will also increase with bend which will reduce the energy of the flowing flumes. The additional loss will happen in the flow through breather pipe (302, 401) known as bending losses, which depend upon the total length of the bend and ratio of radius of curvature of bend and pipe diameter. The ratio of curvature is usually the center line of the bend. With optimum bending angle Oc, the higher temperature drop will be seen as the vapour pressure drop and liquid pressure drop increases as the bending angle increases and the pressure drop may largely affect the temperature distribution of the breather pipe (302, 401) and breather hose (303, 402). Moreover the breather pipe (302, 401) is provided very close to the exit of the cylinder head cover (210) such that the ratio of the length of the breather pipe (302, 401) from heating zone to the total length of the breather pipe (302, 401) is smaller which will also decrease the temperature of the fumes as the fumes flow velocity and vapour pressure drop at different bending positions varies.
[00034] Figure 5 illustrates the graphical representation depicting test results where present breather system reduces the oil accumulated inside the drain pipe (307) as compared to the oil accumulation when the conventional breathing system is used. Preferably, the vertical axis signifies the oil collection in milliliter and horizontal axis signifies the distance covered in kilo meters. As during the test condition, the vehicle (100) having present breathing system reduces the oil content in the air filter assembly (301). This reduced oil content inside the drain tube (307) leads to more life of the air filter assembly (301). A line 501 represents the oil accumulation inside the air filter assembly (301) as per conventional system. Further, a line 502 represents the oil accumulation inside airfilter assembly (301) as per present invention. Thus, it is clearly evident from the graph that oil accumulation is more in the conventional air filter assembly as compare to the proposed system for same distance traveled by the vehicle. Therefore, conventional airfilter assembly are not environment friendly as they emit more while fumes generated because more oil is accumulated inside the air filter assembly (301).
[00035] Figure 6 illustrates a partial perspective view of the two wheeled vehicle (100) with an enlarged local view showing the breathing system as per first embodiment. A battery pack (601) which is mounted on the floor board of the vehicle (100). The battery pack (601) is use to power the traction motor which is mounted on the rear wheel (108) of the vehicle (100). An electronic component (602) like controller (602) which is used to control the function of vehicle is connected to the battery pack (601) and traction motor (107). The electronic component (602) configured to control varied electrical function of the vehicle (100). The electronic component (602) is mounted over the top of the engine (106) on a bracket (603) welded to the frame assembly (FA). The breather pipe (302) which is mounted over the cylinder head cover (210) provides the optimum gap with bracket (603) holding the electronic component (602). Hence this avoids fouling with bracket (603). The controller (602) positioned near to the battery pack (601) as well traction motor (107) so as to reduce the current losses. Now because of the above said condition of the electronic component (602), the utility box mounting points has a layout constraint regarding the height to which electronic component (602) can move up. Further, moving of electronic component (602) in front direction of the vehicle (100) will decrease the leg space of the vehicle (100). Hence the breather tube (302) is mounted at the top surface of the cylinder head cover (210) making predetermined angle with the longitudinal axis (L-L’) & also provide optimum clearance with bracket (603) as per first embodiment. Further as per second embodiment the breather tube (401) (as shown in Fig. 3b) is disposed on the side surface of the cylinder cover head (210), Preferably on the left side of the said vehicle (100) which is opposite to the exhaust system of the vehicle (100). The breather pipe (401) makes a predetermined angle with longitudinal axis (L-L’) of the vehicle (100) which results in optimum working or operating clearance with bracket (603).
[00036] Hence, providing bend in breather pipe (302, 401) will help in more heat loss from fumes as heat conducted by metal breather pipe will be higher than rubber tube due to higher coefficient of heat transfer. So, by reducing the fumes velocity, head and temperature, most of the oil will be separated in the breather pipe (302, 401) and will get back to the engine (106) rather than depositing in the air filter assembly (301). Thus, the breathing efficiency will improve with less deposition of oil in the air filter assembly (301). Also, it will increase the serviceability period of the air filter assembly (301) require for cleaning drain tube (307).
[00037] Furthermore, bending away of breather tube (302, 401) from the exhaust side will help in reducing the length of breather pipe (302, 401), since routing the breather hose (303, 402) from there will be shorter and this will also avoid the use of clamping member for proper routing to the air filter assembly (301).
[00038] The present invention as per preferred embodiment is also implementable with minimal changes in existing layout and minimum modification of frame component supporting the internal combustion (IC) engine (106).
[00039] The present invention as per preferred embodiment can also be implemented without change in design of the crankcase (RH, LH) where only change in the cylinder head cover alone may be required, without any significant modification of an existing design which further reduces the cost as less complex machinability of intrinsic parts is required.
[00040] The present invention as per present embodiment leads to reduction of part count and reduces the cost as eliminates the extra clamping members to hold the breather hose while overcoming all problems cited earlier & other problems of known art.
[00041] Moreover, the breather tube is disposed at downstream end with reference to the air filter assembly, this allows condensed oil to back flow to the engine instead of accumulating inside the air filter.
[00042] While the present invention has been shown and described with reference to the foregoing preferred embodiments, it will be apparent to those skilled in the art that changes in form, connection, and detail may be made therein without departing from the spirit and scope of the invention.
List of references
FA - Frame assembly
F- Front
R –Rear

X – X’ – Lateral axis
L – L’ – Longitudinal axis
A-A’ – Breather hose axis
100 – Vehicle
101 - Headlight
102 - Front panel
103 - Head tube
104 - down tube
105 - Sub frame
106 - Internal combustion (IC) engine
107 - Traction motor
108 - Rear wheel
109 - Leg shield
110 - Under-seat cover
111 - A left and a right-side panel
112 - Front fender
114 - Floorboard
113 – Reflector
115 - Seat assembly
116 - Rear fender
117 – Front suspension(s)
118 – Rear suspension
119 – Rear lamp assembly
120 – Front wheel
121 – Handle bar assembly
122 – Pillion handle rest
123 – Swing arm
124 – Mirror
201- Cylinder head
202- Cylinder block
203- Piston
2030 - Piston ring
203w - Piston cylinder wall
204 - Connecting rod
205- Crankshaft
205L - Crankshaft RH
205R - Crankshaft LH
206- Spark plug
207- Fins
208- Crankcase
208R - Crankcase RH
208L - Crankcase LH
209- Oil path
209P - Plug hole
210- Cylinder head cover
211- Cam shaft
212- Cam chain
213- Bearing
214- Maze
301- Air filter assembly
302- Breather pipe
303-Breather Hose
303c- Downstream end
303a, 303b- Plurality of bends
303d – Upstream end
304- Fastening means
305- Cooling means
307- Drain tube
401- Breather pipe
402- Breather hose
402a, 402b – Plurality of bends
402c – Downstream end
402d- Upstream end
501- Line 1 – Conventional system
502- Line 2 – Proposed system
601- Battery pack
602- Electronic component/Controller
603- Bracket