DESC:TECHNICAL FIELD
[0001] The present subject matter relates generally to a swinging type power train for a two-wheeled vehicle and more particularly, but not exclusively to a swinging-type power unit mounted with a heat exchange assembly.

BACKGROUND
[0002] Generally, , in a two-wheeled vehicle with a step-through type frame assembly, a swinging type-power unit is mounted to the frame assembly of the vehicle. The power unit includes an internal combustion engine assembly. Air-fuel mixture is combusted in a cylinder of engine assembly. The combustion of the air-fuel mixture results in movement of a piston, which in turn rotates a crankshaft resulting in generation of torque and power. Also, combustion of the air-fuel mixture results in generation of heat. The heat generated is to be dissipated in the atmosphere for cooling the engine assembly. The heat generated during the combustion affects performance of the engine. Moreover, with increased engine capacities, the amount of heat generated is also increased.
[0003] Generally, in a step-through vehicle, an internal combustion engine acts as the power unit. The engine has a cylinder body and a cylinder head. The engine is disposed rearwardly of a step-through portion of the vehicle. Moreover, in the proximity of engine, plurality of panels are being provided covering at least a portion of the engine. Therefore, the flow of air near the cylinder head and the cylinder body is restricted. Therefore, a forced cooling system is used in such vehicles. Moreover, for efficient cooling, a liquid cooled type forced cooling system is preferred.

BRIEF DESCRIPTION OF DRAWINGS
[0004] The detailed description of the present subject matter is described with reference to the accompanying figures. Same numbers are used throughout the drawings to reference like features and components.
[0005] Fig. 1 illustrates a left side view of a two-wheeled vehicle, in accordance with an embodiment of present subject matter.
[0006] Fig. 2 (a) depicts a right side view of a swinging type power train, in accordance with an embodiment of the present subject matter.
[0007] Fig. 2 (b) depicts a bottom perspective view of the power train depicted in Fig. 2 (a).
[0008] Fig. 2 (c) depicts a schematic view of coolant path, in accordance with the embodiment of Fig. 2 (b).
[0009] Fig. 2 (d) depicts a front view of a power unit, in accordance with the embodiment of Fig. 2 (b).
[00010] Fig. 3 depicts a partially exploded view of the power unit, in accordance with another embodiment of the present subject matter.
[00011] Fig. 4 depicts a left side view of the vehicle and air towards the power train, in accordance with an embodiment of the present subject matter.

DETAILED DESCRIPTION
[00012] Generally, in a vehicle with a step-through type frame assembly, the engine is disposed below a seat assembly. Also, a utility box, for storage, is disposed below the seat assembly and above the engine assembly. Also, a carburetor is disposed upwardly of the engine assembly. Generally, a heat exchange assembly is also disposed in proximity to the engine assembly. Generally, hose(s) are used to functionally couple the engine assembly, a heat exchange assembly, and a coolant pump to enable flow of coolant. Generally, the hose(s) known in the art are made from natural or synthetic rubbers. The hose(s) are subject to stress due to pressure and heat. In addition, the hose(s) are prone to ageing and leakage. Additionally, the hose(s) are disposed such that, they may foul with parts of the engine assembly. Moreover, there is a need for frequent maintenance of the hose(s). In addition, the engine assembly is compactly packaged that requires a compact routing of the hose(s).
[00013] Hence, it is an object of the present subject matter is to address at least the above-mentioned problems and/or disadvantages and to provide at least the advantages described below. Accordingly, an aspect of the present subject matter is to provide a vehicle with a swinging type power unit. The power unit of the present subject matter is provided with a heat exchange assembly with improved heat dissipation. Another object of the present subject matter is, to provide a hose assembly for coupling the power unit and the heat exchange assembly. Additional object being, the hose assembly is maintenance free and improves reliability. According to another object, the engine assembly is compactly packaged.
[00014] The power unit includes a cylinder portion comprising a cylinder body and a cylinder head. A heat exchange assembly is disposed on one lateral side of the power unit and a coolant pump is also mounted to said power unit and said coolant pump is driven by said power unit. Plurality of hoses functionally connects the heat exchange assembly to a cooling jacket of the power unit. The plurality of hoses includes a first hose member made of a rigid material including metal and the first hose member functionally connects said heat exchange assembly to a cooling jacket of the power unit through a coolant pump. The first hose member is disposed below a lower facing side of said cylinder portion. The functional connection enables flow of coolant from the heat exchange assembly to the cooling jacket.
[00015] In an embodiment, the present subject matter provides a vehicle with a step-through frame assembly with a swinging type power unit. The power unit is disposed rearwardly of the step-through portion. The power unit is functionally connected to the rear wheel of the vehicle. The vehicle being mounted with a radiator that acts as a heat exchange member. The radiator comprises of a radiator inlet port and a radiator outlet port. The radiator is disposed in one lateral side of the power unit. A coolant pump is mounted to the power unit and being disposed in other lateral end of the power unit. The coolant pump also has a pump-inlet port and a pump-outlet port. In an embodiment, the coolant pump is functionally coupled to the camshaft.
[00016] Further, a cooling jacket being integrally provided around at least a portion of the power unit. In a preferred embodiment, the cooling jacket is being disposed around at least a portion of a cylinder block, and a cylinder head. In one embodiment, the cooling jacket includes a path that covers at least a portion of the cylinder head cover, annularly passing through a spark plug. A coolant is provided that circulates within a loop formed by the coolant pump, the radiator and the cooling jacket. The coolant pump circulates the coolant through the cooling jacket to the radiator. The coolant gets heated upon passing through the cooling jacket that is being sent to the radiator through a thermostat. The radiator enables heat exchange and cools the coolant.
[00017] Further, plurality of hoses connects the radiator, the cooling jacket, and the coolant pump. In a preferred embodiment, the radiator is disposed towards one lateral end of the vehicle and the coolant pump is disposed in other lateral end of the vehicle. A first hose member of the plurality of hoses connects the radiator outlet port to the coolant pump-inlet port. The first hose member extends downward from the coolant pump-inlet port and extends substantially in a lateral direction downwardly of the cylinder block, and towards the radiator outlet. Further, the plurality of hose member connect the pump-outlet port to the cooling jacket inlet disposed in the cylinder block, the cooling jacket output disposed in the cylinder head to the radiator. At least one hose of the plurality of hoses being made of any known metal. The hose member made of metal enables further cooling of coolant flowing through the hose member. In another embodiment, a guide member is provided on the engine assembly for supporting the first hose member. Also, the guide member is provided with a dampening member, which is made an elastic material, that dampens any vibrations from the engine.
[00018] The power unit is forwardly inclined. Therefore, the first hose member being disposed substantially downwardly of the cylinder block is being exposed to the airflow and the cooling of the coolant flowing through the hose member is achieved, when the vehicle is in motion. Therefore, the present subject matter enables additional cooling through the hose member.
[00019] In addition, as the radiator is provided with the radiator inlet port at the top portion and the radiator outlet port in the bottom portion of the radiator, and the provision of the first hose member substantially downwardly of the cylinder block enables improve flow of coolant that is assisted by gravity. Further, the present subject matter utilizes a hose member being made of metal thereby eliminating the need for higher bend radius resulting in a compact layout of the power unit thereby the utility space is not compromised.
[00020] Also, fouling of the hose member with other parts of the power unit is eliminated. Also, serviceability is improved as the need for frequent servicing is eliminated by the present subject matter. Life of the system is also improved as the first hose member eliminates expansion or sagging. Efficiency of the power unit is also improved.
[00021] 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.
[00022] Arrows wherever provided in the top right corner of figure(s) in the drawings depicts direction with respect to the vehicle, wherein an arrow F denotes front direction, an arrow R indicates rear direction, an arrow Up denotes upward direction, an arrow Dw denotes downward direction, an arrow RH denotes right side, and an arrow LH denotes left side.
[00023] Fig. 1 illustrates a left side view of a step-through type vehicle, in accordance with an embodiment of the present subject matter. The vehicle has a frame assembly 105 that includes a head tube 105A, a main tube 105B extending downwardly rearward from the head tube, and a pair of railing 105C. The frame assembly 105 extends from a front portion F towards a rear portion R of the vehicle. The main tube 105B may include a down tube extending rearwardly from the main tube 105B. A handlebar assembly 110 is connected to a front wheel 115 through one or more front suspension(s) 120 and a steering shaft (not shown). Further, the steering shaft is rotatably disposed to the head tube 105A. A seat assembly 125 is disposed above the pair of railings 105C, which is formed by a left railing and a right railing. A utility box (not shown) is below the seat assembly 125 and being supported by the pair of railings 105C.
[00024] A power unit 200 is functionally connected to a rear wheel 135 through a transmission system. The rear wheel 135 is connected to the frame assembly 105 through one or more rear suspension(s) 140. The power unit 200 is disposed below the utility box and rearwardly of a step-through portion ST defined formed by the frame assembly 105. Further, the power unit 200 is swingably connected to the frame assembly 105 through a toggle link (not shown). The transmission system may be a variable transmission type or a fixed gear ratio type.
[00025] A front fender 145 is covering at least a portion of the front wheel 115. A floorboard 150 is disposed at the step-through portion ST. The user can operated the vehicle by resting his feet on the floorboard 150, in a sitting position. A fuel tank (not shown) is positioned below the seat assembly 150 and above the rear wheel 135. A rear fender 155 is covering at least a portion of the rear wheel 135. The vehicle is provided with plurality of panels including a front panel 160A disposed below the handle bar assembly 110. A leg shield 160B is provided in an anterior portion of the step-through portion ST. Further, a seat bottom panel 160C is disposed below the seat assembly 125 and forwardly of the power unit 200. A side panel(s) 160D disposed in a rear portion of the vehicle that covers at least a portion of the utility box, the power unit 200 and other parts disposed below the seat assembly 125. Also, the vehicle comprises of plurality of electrical/electronic components including a headlight, a tail light, a battery (not shown), a transistor controlled ignition (TCI) unit (not shown), an alternator (not shown), a starter motor (not shown).
[00026] Fig. 2 (a) depicts a right side view of a power unit, in accordance with an embodiment of the present subject matter. Fig. 2 (b) depicts a bottom perspective of the power unit. Fig. 2 (c) depicts a schematic view of coolant path. Fig. 2 (b) depicts a front view of the power unit. An internal combustion acts as the power unit 200 comprising of a crankcase 205L, 205R having a crankcase-left member 205L (shown in Fig. 2 (b)) disposed on left hand side LH and a crankcase-right member 205R disposed on the right hand side RH, which are adapted to support parts including crankshaft, gears, and bearings (not shown). In the present embodiment, the crankcase-left member 205L extends rearward in the longitudinal direction of the vehicle, farther than an end portion of the crankcase right member 205R till the rear wheel axle. The crankcase left member 205L is adapted to support the transmission system such as continuously variable transmission (CVT). The power unit 200 includes a cylinder portion CP including a cylinder block 210 and a cylinder head 215. The cylinder block 210 is provided with a cylinder bore (not shown) in which a piston (not shown) is slidable. The piston is connected to the crankshaft (not shown) by a connecting rod. The cylinder head 215 is mounted to the cylinder block 210 and the cylinder head is capable of supporting a valve train of the power unit 200. A cylinder head-cover 220 is mounted to the cylinder head 215. Moreover, the cylinder block 210 is mounted to the crankcase 205L, 205R. Also, the crankcase 205L, 205R includes a mounting portion 205A for swingably connecting the power unit 205 to the frame assembly 105. The first hose member 305 is disposed upwardly of said mounting portion 205A and downwardly of said cylinder portion CP.
[00027] Further, a crankcase right cover 225R is mounted to the crankcase 205L, 205R on a right hand side RH lateral face of the crankcase 205L, 205R. Similarly, a crankcase left cover 225L is mounted to the crankcase 205L, 205R on a left hand side LH lateral face of the crankcase 205L, 205R. A rear wheel axle 240 is disposed in a rear portion of the crankcase left member 225L, and the crankcase left member 225L is substantially rearward of a rear portion of the crankcase right member 225R. A cooling fan cowl 230 is mounted to the lateral right side RH face of the crankcase 205L, 205R. A cooling fan (not shown) is functionally coupled to the crankshaft and disposed within the cooling fan cowl 230. In a preferred embodiment, the cooling fan cowl 240 is made of rigid material and the rigid material includes any known metal. The cooling fan cowl 240 covers at least a portion of the cooling fan. The radiator 230 is mounted to the cooling fan cowl 240 that is adapted to support the radiator 230. The radiator 230 is provided with plurality of fins that extends in the longitudinal direction of the vehicle 100. Further, at least a portion of the radiator 230 is exposed to atmosphere in the vehicle 100 disposed with plurality of panels.
[00028] In an embodiment, a cooling jacket J is integrally formed with the cylinder block 210 in the walls of the cylinder block, and in the cylinder head 215. A coolant pump 235 is mounted to the cylinder head 215. In a preferred embodiment, a coolant pump 235 (shown in Fig. 2 (b)) is mounted to the cylinder head 215 on the left hand side LH lateral face. A spark plug is disposed on the right hand side LH. The radiator 230 comprises a radiator inlet port 230A and a radiator outlet port 230B. Also, the coolant pump 235 comprises a pump-inlet port 235A and a pump-outlet port 235B. The coolant liquid helps in heat exchange of the heat generated due to combustion happening inside the cylinder. The coolant is circulated through the coolant pump 235, the cooling jacket J and the radiator 230. The plurality of fins of the radiator 230 has enable in cooling of the coolant that is circulated through the plurality of fins. Furthermore, the cooling fan disposed rearwardly of the radiator helps in cooling of the coolant. The coolant pump 235, the cooling jacket J and the radiator 230 being connected by plurality of hoses 305, 310, 315.
[00029] The radiator outlet port 230A is connected to pump inlet port 235A through the first hose member 305. The pump outlet port 235B is connected to the cooling jacket J inlet disposed in the cylinder block though a second hose member 310. The cooling jacket J outlet, which is disposed in cylinder head, is coupled to the radiator-inlet port 230A by a third hose member 315. Further, the third hose member 315 is coupled to the cooling jacket J through a thermostat housing 330. The thermostat housing 330 is adapted to accommodate a thermostat. The second hose member 310 and the third hose member 315 being made of an elastic material, as the length of the connection is relatively short compared to the first hose member 305.
[00030] In a preferred embodiment, the radiator 230 is disposed on the right hand side RH and the coolant pump 235 is disposed on the left hand side LH, and the first hose member 305 extends downward from the coolant pump-inlet port 235A and extends substantially in a lateral direction downwardly of the cylinder block 210, and towards the radiator outlet port 230B. In an embodiment, a substantial portion of an axis of the first hose member 305 is either parallel or at an acute angle to a lateral axis RH-LH of the vehicle 100. The radiator outlet port 230B is provided in down portion and a front portion of the radiator 230. A radiator cap is provided in a top portion for filling the coolant. In a preferred embodiment, the first hose member 305 is made of a known metal. The first hose member 305, which is made of metal and being disposed downwardly of the cylinder block 210 enables further cooling of coolant flowing through the first hose member 305. Therefore, the heat exchange is effectively performed. In addition, a guide member 320 is provided for supporting the first hose member 305. Further, the guide member 320 is provided with a dampening member 320A, which is made an elastic material. The dampening member 320A dampens any vibrations from the engine, thereby reducing formation of air bubbles in the coolant. The guide member 320 may be integrally formed with the crankcase 205L, 205R.
[00031] Fig. 3 depicts a partially exploded view of the power unit, in accordance with another embodiment of the present subject matter. The first hose member 305 is provided with plurality of fins 335 that are provided circumferentially on the first hose member 305. The plurality of fins 335 are disposed distributively on a peripheral surface of said first hose member 305. The plurality of fins 335 provide greater contact surface with the running airflow. Therefore, coolant is effectively cooled.
[00032] Further, one end 305A of the first hose member 305 is secured to the radiator outlet port 230B by means of one or more fasteners 325. Similarly, another end 305B of the first hose member 305 is secured to the coolant pump-outlet port 235B through one or more fasteners 325. Further, in an embodiment, a toric joint member(s) 325A, 325B having a cross-section, at a connecting portion, similar to the cross-section of the first hose member 305 is disposed there between at the joining portions. The toric joint member(s) 325A, 325B is made of an elastic material for providing effective sealing. In an embodiment, the first hose member 305 includes one or more brass joints secured thereof.
[00033] In another embodiment, a ferrule and nut assembly (not shown) is used to connect the hose member to the radiator and the pump assembly.
[00034] Fig. 4 depicts a left side view of a vehicle mounted with the power unit, in accordance with an embodiment of the present subject matter. The power unit 200 being a swinging type unit, which is connected to the frame assembly 105 (shown in Fig. 1) through a toggle link (not shown). The power unit 200 is forwardly inclined. The first hose member 305 made of any known metal is being disposed downwardly of the cylinder block 210. Further, the hose member improves the effectiveness of the heat exchange. Further, when the vehicle 100 is motion, atmospheric air is directed toward the power unit 200 from below the step-through portion. Therefore, the first hose member 305 that is being disposed substantially downwardly of the cylinder block is being exposed to the airflow AF and the cooling of the coolant flowing through the first hose member 305 is achieved. The airflow AF for below the step-through portion provides natural air-cooling of the coolant in addition the heat exchange provided by the radiator 230. The power unit 200 disposed rearwardly of the step-through portion ST and below the seat assembly 125 provides improved cooling as the airflow AF is passing by the first hose member 305 that enables cooling of the power unit 200, especially the cylinder portion CP.
[00035] It is to be understood that the aspects of the embodiments are not necessarily limited to the features described herein. 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.
,CLAIMS:I/We claim:
1. A swinging-type power unit (200) for a two-wheeled vehicle (100), said power unit (200) comprising:
a cylinder portion (CP) including a cylinder body (210) and a cylinder head (215), and said cylinder portion (CP) is forwardly inclined;
a heat exchange assembly (230) disposed on one lateral side of said power unit (200), said heat exchange assembly (200) includes a heat exchange-inlet port (230A) and a heat exchange-outlet port (230B);
a coolant pump (235) mounted to said power unit (200) and said coolant pump (235) is driven by said power unit (200);
a plurality of hoses (305, 310, 315) functionally connect said heat exchange assembly (230) to a cooling jacket (J) of said power unit (200);
characterized in that,
said plurality of hoses (305, 310, 315) includes a first hose member (305) made of a rigid material, wherein said first hose member (305) functionally connects said heat exchange assembly (230) to said cooling jacket (J) through said coolant pump (235), and said first hose member (305) disposed below a lower facing side of said cylinder portion (CP).
2. The swinging-type power unit (200) of claim 1, wherein said coolant pump (235) is disposed on other lateral side of said power unit (200) and said first hose member (305) extends downward from said coolant pump (235) and substantially in a lateral direction towards at least one port of said heat exchange-inlet port (230A) and said heat exchange outlet port (230B).
3. The swinging-type power unit (200) of claim 1, wherein said first hose member (305) includes plurality of fins (335) disposed distributively on a peripheral surface of said first hose member (305).
4. The swinging-type power unit (200) of claim 1, wherein said plurality of hoses (305, 310, 315) including said first hose member (305) are selectively made of rigid material including metal.
5. The swinging-type power unit (200) of claim 1, wherein said cylinder portion (CP) is mounted to a crankcase (205L, 205R) and said first hose member (305) is supported by a guide member (320) affixed to said crankcase (205L, 205R) of said power unit (200).
6. The swinging-type power unit (200) of claim 1, wherein said guide member (320) includes a damping member (320A) sandwiched between said first hose member (305) and said guide member (320).
7. The swinging-type power unit (200) of claim 1, wherein said first hose member (305) is having one end secured to a pump outlet port (235A) of said coolant pump (235) and other end of said first hose member (305) is secured to said heat exchange inlet port (230A) of said heat exchange assembly (230) through one or more fasteners.
8. The swinging-type power unit (200) of claim 1, wherein said first hose member (305) is disposed above a mounting portion (205A) of the crankcase (205L, 205R).
9. The swinging-type power unit (200) of claim 1, wherein said frame assembly (105) of said two-wheeled vehicle (100) includes a step-through portion (ST) and said power unit (200) is disposed rearwardly of said step-through portion (ST).
10. The swinging-type power unit (200) of claim 1 or 9, wherein said first hose member (305) is disposed rearwardly of said step-through portion (ST).