DESC:FIELD OF INVENTION
[0001] The present invention relates to an internal combustion engine for automobiles and more particularly to a starting system of a single gear ratio engine or single speed engine.
BACKGROUND OF INVENTION
[0002] A vehicle with a single gear ratio has its speed directly proportional to the throttle. Various methods of starting an internal combustion engine are known. Such methods of starting an internal combustion engine include kick-starting method and electric start method. In the electric start method of cranking an internal combustion engine, a motor is connected to a crankshaft, either directly or through some intermediate gear mechanisms. Similarly, in a kick-start mechanism of cranking an internal combustion engine, a motor is connected to a crankshaft, either directly or through some intermediate gear mechanisms. In the aforesaid single gear ratio internal combustion engine, even after the engine cranks, either by the kick-start method or by the electric start method, a number of intermediate gears keep on rotating with the crankshaft, thus adding to high inertia which further leads to loss of power. Subsequently, these continuous rotating masses further lead to generation of noise and vibrations in said single gear ratio internal combustion engine.
SUMMARY OF THE INVENTION
[0003] Hence, to obviate problems associated with the starting mechanism of single gear ratio internal combustion engines, which have an advantage of reduced power loss, reduced noise and vibrations. The current invention proposes an internal combustion engine with a uni-directional power flow mechanism wherein after cranking of said single gear ratio engine; the intermediate gears are isolated which avoids unnecessary rotation of mass thus saves mechanical power and reduces the noise and vibrations.
BRIEF DESCRIPTION OF DRAWINGS
[0004] Figure 1 shows typical two-wheeled vehicle with single gear ratio internal combustion engine.
[0005] Figure 2 shows a typical single gear ratio internal combustion engine.
[0006] Figure 3 Illustrates sectional view of the single gear ratio internal combustion engine.
[0007] Figure 4 illustrates the relative rotation diagram of crankshaft, starter motor idler gear and one-way clutch outer race and the crankshaft.
[0008] Figure 5 illustrates pillion handle on rear frame structure of two-wheeled vehicle as per current invention.
[0009] Figure 6 Illustrates the relative rotation diagram of crankshaft, kick-starter idler gear and one way clutch outer race and the crankshaft.
DETAILED DESCRIPTION OF THE INVENTION
[00010] The current invention discloses a uni-directional power flow mechanism wherein after cranking of said single gear ratio engine; the intermediate gears are isolated which avoids unnecessary rotation of mass thus saves power and reduces the noise and vibrations.
[00011] Figure 1 shows typical two-wheeled vehicle with single gear ratio internal combustion engine. Figure 1 illustrates rider seat 1, fuel tank 2, floorboard 3, engine 4, front wheel 5, rear wheel 6 and a vehicle 10. The internal combustion engine as illustrated in the current invention is equipped with a single gear ratio transmission system. In internal combustion engines equipped with a single gear ratio transmission, the vehicle speed is directly proportional to the throttle percentage.
[00012] Figure 2 shows a typical single gear ratio internal combustion engine. Figure 2 further illustrates the engine 4, cylinder head 21, cylinder block 22, crankcase 23 and crankshaft axis X-X'. The combustion of fuel takes place inside the cylinder within the cylinder block. The axis X-X’ is the crankshaft rotation axis. As illustrated in Figure 2, the crankcase 23 covers the cylinder, connecting rod, the piston and other transmission components.
[00013] Figure 3 Illustrates sectional view of the single gear ratio internal combustion engine. Figure 3 shows electric starter motor 25, idler shaft 26, electric starter idler gear 27, clutch drum 28, centrifugal clutch 29, ring gear 30, drive shaft 31, cover clutch 32, primary driven gear 33, kick-starter idler gear 34, kick-starter drive gear 35, ratchet kick-starter 36, kick-starter shaft 37, one way clutch 38, gear oil pump drive 39, cam chain sprocket 40, one way clutch drive gear 41, crankshaft 42 and connecting rod 43.
[00014] As illustrated in Figure 3, the electric starter motor shaft drives the idler shaft 26. The idler shaft 26 is mechanically coupled to a ring gear 30. The ring gear 30 is further mechanically coupled to the outer race 46 of a uni directional power flow apparatus 38. The inner race 45 of this uni directional power flow apparatus 38 is mechanically coupled to the crankshaft 42. As illustrated through the power flow arrows, the electric starter motor shaft drives said electric starter idler gear 27. The electric starter idler gear 27 rotates the outer race 46 of said uni directional power flow apparatus 38. At lower rotational speeds, the outer race 46 of said uni directional power flow apparatus 38 drives the inner race 45 of the uni directional power flow apparatus 38. Since the inner race 45 of the uni directional power flow apparatus 38 is mechanically coupled to said crankshaft 42, the crankshaft 42 is rotated. Due to combination of rotation of said crankshaft 42 and a pre-determined timing of spark through ignition control unit, the combustion of fuel inside engine starts. Once the combustion of fuel inside the engine has started, the inner race 45 of said uni directional power flow apparatus 38 rotates at a higher rotational speed as compared to the outer race 46 of said uni directional power flow apparatus 38, the mechanical coupling between said inner race 45 of said uni directional power flow apparatus 38 and the outer race 46 of said uni directional power flow apparatus 38 is lost and the power is not transmitted from said inner race 45 of said uni directional power flow apparatus 38 to the outer race 46 of said uni directional power flow apparatus 38. Since the power is not transmitted from the inner race 45 of said uni directional power flow apparatus 38 to the outer race 46 of said uni directional power flow apparatus 38, the ring gear 30 does not rotate. Since the ring gear 30 does not rotate, no power is transmitted from the ring gear to said electric starter motor and the problem of large mass rotating even after the cranking of engine is solved.
[00015] Figure 4 illustrates the relative rotation diagram of crankshaft, starter motor idler gear and one-way clutch outer race 46 and the crankshaft. Figure 4 illustrates electric starter idler gear 27, one-way clutch 38, crankshaft 42, starter motor idler gear RPM ?1, and crankshaft RPM ?2. As shown in Figure 4 when the rotational speed of the electric starter idler gear 27 ?1 is equal to the rotational speed of the crankshaft ?2, the outer race 46 of said uni directional power flow apparatus 38 is stationary.
[00016] When the rotational speed of the electric starter idler gear 27 ?1 is more than the rotational speed of the crankshaft ?2, the outer race 46 of said uni directional power flow apparatus 38 drives the inner race 45 of said uni directional power flow apparatus 38, which in turn drives the crankshaft 42. When the rotational speed of the electric starter idler gear ?1 is less than the rotational speed of the crankshaft ?2 (after cranking), the outer race 46 of said uni directional power flow apparatus 38 is disconnected mechanically from said inner race 45 of said uni directional power flow apparatus 38, hence unable both to drive or to be driven, from said inner race 45 of said uni directional power flow apparatus 38. Hence, the other intermediate gears are prohibited to rotate unnecessarily after the engine cranking. Thus reducing the power loss, noise and vibrations.
[00017] Figure 5 illustrates pillion handle on rear frame structure of two-wheeled vehicle as per current invention. Figure 5 further illustrates a clutch drum 28, centrifugal clutch 29, drive shaft 31, cover clutch 32, primary driven gear 33, kick-starter idler gear 34, kick-starter drive gear 35, ratchet kick-starter 36, kick-starter shaft 37, one way clutch 38, gear oil pump drive 39, cam-chain sprocket 40, one way clutch drive gear 41, crankshaft 42, crankshaft axis X-X'. The kick-starter idler gear 34 is mechanically coupled to the outer race 46 of a uni directional power flow apparatus 38. The inner race 45 of this uni directional power flow apparatus 38 is mechanically coupled to the crankshaft 42. As illustrated through the power flow arrows, the kick-starter shaft 37 drives said kick-starter idler gear 34. The kick-starter idler gear 34 drives the outer race 46 of said uni directional power flow apparatus 38. At lower rotational speeds, the outer race 46 of said uni directional power flow apparatus 38 drives the inner race 45 of the uni directional power flow apparatus 38. Since the inner race 45 of the uni directional power flow apparatus 38 is mechanically coupled to said crankshaft 42, the crankshaft 42 is rotated. Due to combination of rotation of said crankshaft 42 and a pre-determined timing of spark through ignition control unit, the combustion of fuel inside engine starts. Once when the combustion of fuel inside the engine takes place, the inner race 45 of said uni directional power flow apparatus 38 rotates at a higher rotational speed as compared to the outer race 46 of said uni directional power flow apparatus 38, the mechanical coupling between said inner race 45 of said uni directional power flow apparatus 38 and the outer race 46 of said uni directional power flow apparatus 38 is lost and the power is not transmitted from said inner race 45 of said uni directional power flow apparatus 38 to the outer race 46 of said uni directional power flow apparatus 38. Since the power is not transmitted from the inner race 45 of said uni directional power flow apparatus 38 to the outer race 46 of said uni directional power flow apparatus 38, the kick-starter idler gear 34 does not rotate. Since the kick-starter idler gear 34 does not rotate, no power is transmitted from the kick-starter idler gear 34 to said kick-starter shaft 37, the problem of reverse kick back and the mentioned problem of large mass rotating even after the cranking of engine is solved. Hence, a large power loss along with the undesired noise and vibrations is avoided.
[00018] Figure 6 illustrates the relative rotation diagram of crankshaft 42, kick-starter idler gear 34 and one-way clutch outer race 46. Figure 6 further shows kick-starter idler gear 34, one-way clutch 38, crankshaft 42; kick-starter idler gear RPM ?3, and crankshaft RPM ?2. As shown in Figure 6 when the rotational speed of the kick-starter idler gear ?3 is equal to the rotational speed of the crankshaft ?2, the outer race 46 of said uni directional power flow apparatus 38 is stationary with respect to the inner race 45 of said uni directional power flow apparatus 38.
[00019] When the rotational speed of the kick-starter idler gear ?3 is more than the rotational speed of the crankshaft ?2, the outer race 46 of said uni directional power flow apparatus 38 drives the inner race 45 of said uni directional power flow apparatus 38, which in turn drives the crankshaft 42. While the rotational speed of the kick-starter idler gear ?3 is less than the rotational speed of the crankshaft ?2 (after cranking), the outer race 46 of said uni directional power flow apparatus 38 is mechanically disconnected from said inner race 45 of said uni directional power flow apparatus 38 hence unable for both to drive or to be driven, from said inner race 45 of said uni directional power flow apparatus 38. Hence, the other intermediate gears do not rotate after the engine cranking thereby reducing power loss, noise and vibrations.
,CLAIMS:We claim:
1. An internal combustion engine comprising:
a transmission portion within a crankcase (23) with a single gear ratio system in which the vehicle speed is directly controlled through a throttle (9);
a crankshaft (42) which rotates on its axis to generate power for said transmission portion within crankcase (23);
a kick starting mechanism comprising a kick starter idler gear (34), kick starter drive gear (35), ratchet kick starter (36), kick starter shaft (37) in which said crankshaft (23) is mechanically coupled to said kick start idler gear mechanism (34);
an electric start system comprising an electric starter motor (25), idler shaft (26) and an electric starter idler gear (27) wherein said crankshaft (23) is coupled to said electric starter idler gear (27);
characterized in that:
said crankshaft (23) is mechanically coupled to an inner race (45) of an uni-directional power flow apparatus (38) and said electric starter idler gear (27) is mechanically coupled to an outer race (46) of said uni directional power flow apparatus (38); and
the electric starter idler gear (27) is mechanically coupled to said kick-starter shaft (37) and an electric motor (25).

2. The internal combustion engine as claimed in claim 1 wherein said uni directional power flow apparatus (38) is a one-way clutch.
3. The internal combustion engine as claimed in claim 1 wherein said inner race (45) of the uni directional power flow apparatus (38) and the outer race (46) of the uni directional power flow apparatus (38) are mechanically decoupled once said engine has cranked.

4. The internal combustion engine as claimed in claim 1 wherein said kick-starter idler gears (34) and said kick-starter shaft (37) are mechanically decoupled once said engine has cranked.

5. The internal combustion engine as claimed in claim 1 wherein the outer race (46) of the uni directional power flow apparatus (38) is stationary with respect to the inner race (45) of the uni directional power flow apparatus (38) once a rotational speed of the kick-starter idler gear ?3 is equal to a rotational speed of the crankshaft ?2.

6. The internal combustion engine as claimed in claim 1 wherein the outer race (46) of said uni directional power flow apparatus (38) drives the inner race (45) of said uni directional power flow apparatus (38) once the rotational speed of the kick starter idler gear ?3 is more than the rotational speed of the crankshaft ?2.

7. The internal combustion engine as claimed in claim 1 wherein the outer race (46) of said uni directional power flow apparatus (38) is mechanically decoupled from the inner race (45) of the uni directional power flow apparatus (38) once the rotational speed of the kick starter idler gear ?3 is less than the rotational speed of the crankshaft ?2.