FIELD OF INVENTION

[0001] The present invention relates to a vehicle, and more particularly, to a secondary air supply system and an engine cooling system of the vehicle.

BACKGROUND

[0002] Vehicle, particularly vehicle configured to be ridden such as motorized scooter, motorcycle, three-wheeled vehicle, and four wheeled vehicle such as all-terrain vehicle comprise a secondary air supply device to control the exhaust emissions of an engine. The secondary air supply device comprises a secondary air supply hose provided in fluid communication with an exhaust pipe of the engine. The secondary air supply device utilizes exhaust pulsation of the engine to supply the secondary air into the exhaust pipe. The secondary air supply device introduces secondary air via the secondary air supply hose into the exhaust pipe connected to an exhaust muffler. The secondary air supply hose is generally made of flexible material such as rubber, resin etc. A catalyst converter is provided within the exhaust muffler to convert the secondary air and exhaust gas mixture. However, when the second air supply device is inactive, exhaust gases from the exhaust pipe enters into the secondary supply hose, thereby heating up the secondary supply hose. The material of the secondary air supply hose (rubber or resin) cannot withstand such high temperatures and therefore requires measures against the heating of the secondary supply hose.

SUMMARY OF INVENTION

[0003] In one aspect of the present invention a vehicle is provided. The vehicle is comprising of a body frame and an engine cooling system. The engine cooling system of the vehicle comprises an engine unit coupled to the body frame, the engine unit comprises a crankcase, a cylinder block attached to the crankcase, a cylinder head attached to the cylinder block, a cylinder head cover for covering an opening of the cylinder head, a crank shaft rotatably supported by the crankcase, a cooling fan mounted to the crank shaft. The engine cooling system of the vehicle further comprises an engine case configured to shield at least a portion of the engine unit. The engine case comprises an air inlet and an air outlet. Outside air flows inside the engine case through the air inlet and the inside air exits out of the engine case through the air outlet. The engine cooling system of the vehicle also comprises a secondary air supply system comprising an Air Suction Valve, a vacuum hose, a secondary air inlet, the Air Suction Valve is fludically coupled to the exhaust port through the secondary air supply hose, the secondary air supply hose further comprises a ASV flexible hose, and an ASV metal hose. At least a portion of the ASV metal hose overlaps the air outlet of the engine case in the direction of air flow.

[0004] In an embodiment of the invention, he engine case comprises a plurality of baffles disposed on the air outlet to direct the inside air out of the engine case.

[0005] In an embodiment of the invention, the cylinder head comprises a bracket to support the ASV metal hose.

[0006] In an embodiment of the invention, a bracket covers at least a portion of the air outlet.

[0007] In an embodiment of the invention, the engine unit is swingably coupled to the body frame.

[0008] In an embodiment of the invention, the plurality of baffles are configured to direct the inside air out of the engine case substantially in the same direction as that of the axis of the air outlet.

[0009] In an embodiment of the invention, the plurality of baffles are configured to direct the inside air out of the engine case in the direction at an angle to the axis of the air outlet.

[00010] In an embodiment of the invention, the air inlet is provided on the right side of the engine case and the air outlet is provided on front portion of the engine case.

[00011] In an embodiment of the invention, the cooling fan enclosed in the engine case.

[00012] In accordance with the present invention, the engine cooling system having an

ASV metal hose disposed ahead of the air outlet. The air flowing from the air outlet facilitates in cooling of the ASV metal hose heated due to the flow of exhaust gases. The present invention provides preventive 'measures for the hot exhaust gas affecting the flexible material of the secondary air supply hose.

BRIEF DESCRIPTION OF DRAWINGS

[00013] The invention itself, together with further features and attended advantages, will become apparent from consideration of the following detailed description, taken in conjunction with the accompanying drawings. One or more embodiments of the present invention are now described, by way of example only wherein like reference numerals represent like elements and in which:

[00014] Figure 1 illustrates a side view of an exemplary two wheeled vehicle, according to an embodiment of the present invention;

[00015] Figure 2 illustrates a view of a body frame of the two wheeled vehicle, according to an embodiment of the present invention;

[00016] Figure 3 illustrates a side view of an engine cooling system of the two wheeled vehicle, according to an embodiment of the present invention;

[00017] Figure 4 illustrates a perspective view of the engine cooling system, according to an embodiment of the present invention; and

[00018] Figure 5 illustrates a view of the engine cooling system, according to an embodiment of the present invention.

[00019] Figure 6a illustrates a sectional view of the engine cooling system along a line AA as depicted in the Figure 5, according to an embodiment of the present invention;

[00020] Figure 6b illustrates an embodiment of the baffles, according to an embodiment of the present invention; [00021] Figure 6c illustrates an embodiment of the baffles, according to an embodiment of the present invention.

[00022] The drawings referred to in this description are not to be understood as being drawn to scale except if specifically noted, and such drawings are only exemplary in nature.

DETAILED DESCRIPTION

[00023] While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and will be described in detail below. It should be understood, however that it is not intended to limit the invention to the particular forms disclosed, but on the contrary, the invention is to cover all modifications, equivalents, and alternative falling within the spirit and the scope of the invention.

[00024] The terms“comprises”,“comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a setup, device or method that comprises a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such setup or device or method. In other words, one or more elements in a system or apparatus proceeded by“comprises... a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or apparatus.

[00025] For the better understanding of this invention, reference would now be made to the embodiments illustrated in greater depth in the accompanying figures and description here below, further, in the following figures, the same reference numerals are used to identify the same components in various views.

[00026] While the present invention is illustrated in the context of a saddle riding type vehicle, however, engine cooling system and aspects and features thereof can be used with other type of vehicles as well. The terms “vehicle”, “two wheeled vehicle” and “motorcycle” have been interchangeably used throughout the description. The term“two wheeled vehicle” includes vehicles such as motorcycles, scooters, bicycles, mopeds, scooter type vehicle, all-terrain vehicles (ATV) and the like. [00027] The terms“front / forward”,“rear / rearward / back / backward”,“up / upper / top / upward”, “down / lower / lowerward / downward”, “left / leftward”, “right / rightward” used therein represents the directions as seen from a vehicle driver sitting astride and these directions are referred by arrows Fr, Rr, U, Lr, L, R in the drawing figures.

[00028] Referring to Figure 1, a two wheeled vehicle (100) according to an embodiment of the present invention is depicted. The two wheeled vehicle (100) (hereinafter alternatively referred to as vehicle (100)) referred to herein, embodies a motorized scooter vehicle. Alternatively, the vehicle (100) may embody any other ridden vehicles such as motorcycles, scooters, all-terrain vehicles (ATV) etc. without limiting the scope of the invention.

[00029] The two wheeled vehicle (100) comprises, inter-alia, a front wheel (2) steered by a handle bar (6), a rear wheel (35) driven by an engine unit (200) (shown in Figure 3). The handle bar (6) is steerably supported on a head tube (110) at a front portion of a vehicle body frame (101) (shown in Figure 2). A portion between the handle bar (6) and a seat (12), supported by the vehicle body whereupon passenger places his feet is referred to as a floor (10).

[00030] Further, a two wheeled vehicle (100) is covered by a body cover (13) generally made up of resin material, and a leg shield (9). Generally, the leg shield (9) comprises of an outer leg shield (4) and an inner leg shield (5), which are arranged ahead of the seat (12). The body cover (13) comprises center cover (11), a right side cover (33) and a left side cover (43) (not shown). The seat (12) is disposed on an upper side of the center cover (11) and the left and right side covers (43, 33).

[00031] A rear wheel axle is rotatably supported in a rear end portion of a transmission unit (204) operatively coupled to the engine unit (200) (shown in Figure 3). Further, a rotational power of the crank shaft is transmitted to the rear wheel axle via the transmission unit (204). As a result, the rear wheel (35) supported by the rear wheel axle is driven, resulting in motion of the two-wheeled vehicle (100). An exhaust system (37) of the two wheeled vehicle (100) comprises an exhaust pipe (40) attached to the engine unit (200) (shown in Figure 4), and a muffler (36) integral with or connected to the exhaust pipe (40).

[00032] The two-wheeled vehicle (100) comprises a front fork (1), a front fender (3), a handle bar cover (7), a storage box (15), a storage box lid (17), a mirror (31), a display meter (32), a rear fender (34), a tail light (38), and a rear grip (39). It may be noted that the vehicle is shown to have include above stated parts, however, those skilled in the art would appreciate that the vehicle includes other parts which may not be relevant for explaining the present invention and hence are not shown and described.

[00033] Referring to Figure 2, a body frame (101) of the two-wheeled vehicle (100). The body frame (101) comprises of a head tube (110), a main frame (112), a pair of rear seat sub-frames such as a left rear seat sub-frame (H4a) and a right rear seat sub-frame (H4b). The head tube (110) extends frontward and downward from front portion of the body frame (101). The main frame (112) extends rearward and downward from the head tube (110) and then becomes approximately horizontally and runs parallel to the ground. The main frame (112) has a cross member (124) which is connected to the rear end of the main frame (112), and is extended in the width direction of the vehicle. The left and right rear seat sub-frames (H4a), (H4b) extend from side ends of the cross member (124) in rearward and upward in longitudinal direction of the two wheeled vehicle (100). Rear part of the left and right rear seat sub-frames (H4a), (H4b) curves at the rear end and connected by a bracket (123). The body frame (101) comprises first cross frame (116), and second first cross frame (120). Approximately‘IT character- like front side crossing frame (120) is constructed over the front portion of the left and right rear seat sub-frames (H4a), (H4b). The first cross frame (116) is constructed over the rear side portion of the left rear seat sub- frame (H4a) and the right rear seat sub-frame (H4b). Further, a first U-shaped frame hose (H8a) extends from the left rear seat sub-frame (H4a) at a position near the front side crossing frame (120). Similarly, a second U-shaped frame hose (H8b) extends from the right seat sub-frame (H4b) at a position near the front side crossing frame (120). The first and second U-shaped frame hose (118a), (118b) are used for mounting a foot peg (not shown).

[00034] The body frame (101) comprises a cross tube (122) on upper surface of the front part of the approximately horizontal part of the main frame (112). The cross tube (122) extends along the width direction of the vehicle. A pair of left and right sub-frames (H7a), (H7b) extend back from side ends of the cross tube (122). The left and right sub- frames (H7a), (H7b) extends in rearwards in longitudinal direction of the vehicle (100). The left and right sub-frames (H7a), (H7b) are welded on the cross member (124) forming a step floor structure.

[00035] As illustrated in Figure 2, the engine unit (200) is swingably mounted on the crossing member (124).

[00036] Figure 3 illustrates the engine unit (126) and a transmission unit (204) mounted on the vehicle frame (101). The hanger (150) having two ends in the longitudinal direction of vehicle (100) has its first end mounted pivotally to the body frame (101) by the mounting means (105). The crankcase (214) of the engine unit (200) is swingably connected to the second end of the hanger (150). The rotational motion generated by the engine unit (200) is transmitted to the rear wheel (35) through the transmission unit (204) and hence resulting in the motion of the rear wheel (35).

[00037] In the illustrated example, the engine unit (200) embodies a single-cylinder, four- stroke-cycle and forced-air-cooling engine unit. The engine unit (200) comprises of a crankcase (214), a cylinder block (212) attached to the front end of the crankcase (214), a cylinder head (216) attached to the cylinder block (212), and a cylinder head cover (2l6c) for covering a front opening in the cylinder head (216). The engine unit (200) is disposed within the vehicle layout with its cylinder head cover (216c) positioned towards the front of the two wheeled vehicle (100). A crank shaft (258) (not shown) is rotatably supported by the crankcase (214) and is connected to a piston (not shown). A cooling fan (220) (shown in Figure 4) is mounted on the right side of the crank shaft (258). An exhaust port (41) of the engine unit (200) is internally defined in the cylinder head (216). An exhaust port (41) of the engine unit (200) is internally defined in the cylinder head (216). The exhaust port (41) is fluidically connected to an exhaust manifold (219) of the engine unit (200).

[00038] As illustrated in Figure 4, an engine cooling system (201) comprises an engine case (210) and the engine unit (200), a secondary air supply system (240). The engine case (210) is provided to shield at least a portion of the engine unit (200). The engine case (210) comprises of an air inlet (222a) and an air outlet (222b). In the illustrated example, the air inlet (222a) is provided on the right side of the engine case (210). In the illustrated example, the air outlet (222b) is provided on front portion of the engine case (210) in longitudinal direction of the two wheeled vehicle (100). The cooling fan (220) enclosed in the engine case (210) draws atmospheric air from the air inlet (222a) of the engine case (210) and circulates the air within air passage of the engine case (210). The air after cooling the engine unit (200) exits the engine case (210) from the air outlet (222b).

[00039] Referring to Figure 4, the exhaust system (37) comprises an exhaust pipe (40) and a muffler (36). The upstream end of the exhaust pipe (40) is connected to the exhaust manifold (219) and the downstream end of the exhaust pipe (40) is connected to the muffler (36). Exhaust gas from the exhaust port (41) flows through the exhaust pipe (40) and is released into the atmosphere through the muffler (36).

[00040] The secondary air supply system (240) of the engine cooling system (201) comprises an ASV (Air Suction Valve) (242), a vacuum hose (244), a secondary air inlet (246), a secondary air supply hose (250). In an embodiment, the secondary air supply system (240) also comprises an ASV bracket (218), and a clamp (255). In an embodiment, the ASV (242) receives secondary air from a secondary air cleaner (not shown) through the secondary air inlet (246). The Air Suction Valve (242) is fluidically coupled to the exhaust manifold (219) of the engine unit (200) via the secondary air supply hose (250). The secondary air supply hose (250) comprises of an ASV flexible hose (251) and an ASV metal hose (252). The ASV flexible hose (251) further comprises of a hose upstream end (25 la) and a hose downstream end (25 lb). The ASV metal hose (252) further comprises of a metal upstream end (252a) and a metal downstream end (252b). The hose upstream end (25 la) of the ASV flexible hose (251) is fluidically coupled to the Air Suction Valve (242). The hose downstream end (25 lb) of the ASV flexible hose (251) and the metal upstream end (252a) of the ASV metal tube (252) are fluidically coupled to each other, using the clamp (255). The metal upstream end (252b) of the ASV metal hose (252) is fluidically coupled to the exhaust manifold (219) of the engine unit (200), using the ASV bracket (218). The Air Suction Valve (242) is fluidically coupled to the intake port (not shown) of the engine unit (200) by the vacuum hose (244). Working of Air Suction Valve (242) is known in the art and not described in detail here. The secondary air regulated by Air Suction Valve (242) flows through the secondary air supply hose (250) and finally enters the exhaust manifold (219).

[00041] In an embodiment of the present invention, the ASV flexible hose (251) extends downwards from the Air Suction Valve (242) and along the right side of the engine case (210). Further, the ASV flexible hose (251) is fluidically coupled to the ASV metal hose (252) by the clamp (255). In an embodiment of the invention, the ASV metal hose (252) is having a plurality of bends while extending till the ASV bracket (218) on exhaust manifold (219). In an embodiment of the invention, the ASV metal hose (252) is supported by at least one bracket (260) along the outer surface of the engine unit (126). In an embodiment of the invention the bracket (260) is fixed to the cylinder block (212).

[00042] Due to the exhaust pulsations of the engine (200), the exhaust gas having high temperature can travel through the secondary air supply hose (250). In an embodiment of the invention, as shown in the Figure 5, a portion of the ASV metal hose (252) disposed in front of the air outlet (222b) in such a way that a portion of the ASV metal hose (252) is exposed to the air exiting from the air outlet (222b). The exhaust gas in the ASV metal hose (252) is having a relatively high temperature than the air exiting from the opening (222b) and hence when air contacts the ASV metal hose (252), the temperature of the exhaust gas in the ASV metal hose (252) decrease.

[00043] In an embodiment of the invention, as shown in Figure 5, the engine case (210) comprises of a plurality of baffles (222c) disposed on the air outlet (222b). The baffles (222c) directs the air flowing out of the air outlet (222b). In an embodiment of the invention the baffles (222c) direct the air on the ASV metal hose (252).

[00044] In an embodiment of the invention, as shown in Figure 5, a portion of the ASV metal hose (252) overlaps with the air outlet (222b) in the direction of air coming out of the air outlet (222b). In an embodiment of the invention, the air is flowing out of the engine case (210) and directed by the baffles (222c) in the downwards side of the vehicle (100). In an embodiment, as shown in Figure 6b and Figure 6c, the plurality of baffles (222c) are configured to direct the inside air out of the engine case (210) in a direction at an angle to the axis of the air outlet (222b). In an embodiment, as shown in Figure 6a, the plurality of baffles (222c) are configured to direct the inside air out of the engine case (210) substantially in the same direction as that of the axis of the air outlet (222b).

[00045] In an embodiment of the invention, as shown in Figure 5, the bracket (260) (to support the ASV metal hose (252) is fixed to the cylinder head (216) in such a way that the bracket (260) covers at least a portion of the air outlet (222b). It will result in more air exiting from the remaining uncovered portion of the air outlet (222b and hence more air get in contact with the said portion of the ASV metal hose (252) resulting in more effective cooling of the exhaust gas in the ASV metal hose (252).

[00046] The present invention discloses the engine cooling system (201) having an ASV metal hose (252) disposed ahead of the air outlet (222b). The air flowing from the air outlet (222b) facilitates in cooling of the ASV metal hose (252) heated due to the flow of exhaust gases therein within due to negative pressure developed by pulsation of the engine (200). The present invention provides preventive measures for the hot exhaust gas affecting the flexible material of the secondary air supply hose.

[00047] While few embodiments of the present invention have been described above, it is to be understood that the invention is not limited to the above embodiments and modifications may be appropriately made thereto within the spirit and scope of the invention.

[00048] While considerable emphasis has been placed herein on the particular features of this invention, it will be appreciated that various modifications can be made, and that many changes can be made in the preferred embodiments without departing from the principles of the invention. These and other modifications in the nature of the invention or the preferred embodiments will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.