Title of Invention

DUAL POWER TRAIN FOR A MOTOR VEHICLE

Abstract A dual, power train for a motor vehicle comprising an internal 16 combustion engine transmitting power through a clutch connected to a transmission system; an electric unit for driving a wheel of the vehicle; a controller connected to the electric unit and to a battery pack; a charge port to which the battery pack is connected; a throttle for regulating fuel supply to the engine through a carburetor, the throttle also being connected to the controller through a potentiometer; an ignition switch for operating a spark plug; a mode switch for connecting the throttle to the controller, such that when the mode switch is ON and the ignition switch is OFF, the engine is non-operative and the signal from throttle runs the electric unit through the controller, the power for the electric unit being derived from the battery pack through the controller; and such that when the mode switch is OFF and the ignition switch is ON, the engine is started with the aid of a cranking mechanism, when the clutch automatically disconnects the engine from the transmission system; the speed of the engine increasing, gradually coupling the clutch to the wheel through the transmission system and such that when both the mode switch and the ignition switch are on, the throttle operates the engine through carburetor and electric unit through the controller whereby both the power from, the electric unit and the power from the engine through the transmission system reach the wheel.
Full Text

The current invention relates to powertrain for two wheeler automobiles. It specifically deals with a powertrain system consisting of two sources of power for the vehicle selectively operated by the driver. This powertrain consists of an internal combustion engine, a battery pack to drive an electric unit and a transmission that couples both the source to the wheel.
Internal combustion engines are the most established source of power in the case of automobiles. The thermal efficiency of the internal combustion engines is inherently low and varying over the operating region, leading to poor fuel economy and heavy vehicle out emissions. With the rising cost of the fuel the operating cost of such automobiles is becoming unaffordable to the common mass.
Electric motor driven by battery packs is also used as powertrain in some of the two-wheeler automobiles. These vehicles have the advantage of low cost of operation along with silent and vibration free operation. Nonetheless these automobiles suffer due to limitation on the distance covered per charging of the battery pack. The distance range per battery charge along with the weight of battery pack used places a constraint on the performance of the vehicles with electric powertrain, which are generally accepted as low performance automobiles. The electric powertrain capable of delivering required performance uses costly battery pack and hence becomes unaffordable.
There is other spectrum of two-wheeler automobiles with hybrid powertrain, which use a combination of internal combustion engine and an electric drive. Inclusion of an electrical device, that can operate as motor as well as generator, in the. powertrain along with battery that can temporarily store as well as retrieve the energy generated by the internal combustion engine can be used to operate the internal combustion engine in its efficient zone of operation and hence increasing the fuel economy and reducing the vehicle out emissions. All these transmissions use a multiple number of electrical devices. The electronic control and the large number of mechanical components necessary to support the electronic control increase the cost of the transmission system exorbitantly. Also this increases the volume and weight of these transmissions compared to IC engine versions. Hence small and low cost vehicles with smaller powertrains do not enjoy the benefit.
The present invention was made in this situation so as to have a dual powertrain that will be small and lightweight with cost and weight comparable to a regular internal combustion engine based two-wheeler automobile. Here the electric powertrain and the internal combustion engine are independently coupled to the wheel. The electric unit is capable of both motoring action as well as charging. The electric motor and the battery pack are designed to operate the two-wheeler as in the case of an electric vehicle. This gives the advantage of low cost of operation along with silent and vibration free operation of the automobile. The battery pack is charged using external source such as electric mains and also during regenerative braking of the vehicle. The internal combustion engine is again capable of operating the vehicle at its required performance independently of the electric powertrain. This removes the disadvantage of an electric vehicle with limited distance range per charge of the battery. Also the engine and transmission is

designed to be lightweight in order to reduce the load on the electric powertrain, which is operated most of the time. The transmission is designed so that the two power sources are coupled to the wheel independently and also it is light in weight. The transmission consists of a clutch that selectively disconnects the engine and the wheel when the electric drive is active and during vehicle launch. The transmission is also capable of operating the two power sources in parallel delivering combined power to the wheel. A cranking mechanism to start the engine is also part of the transmission. Hence the vehicle has the inbuilt capability to operate with increased performance if required. This invention allows operating the two-wheeler at the lowest operating cost using electric power drive mode. It also eliminates the low range between charge problems of electric vehicle by having a back up power source in the internal combustion engine. This invention also eliminates the downside of electric vehicle as a low power and low performance vehicle by combining the power from two power sources selectively based on requirement making it a powerful vehicle.
The dual power train for a motor vehicle, according to this invention, comprises an internal combustion engine transmitting power through a clutch connected to a transmission system; an electric unit for driving a wheel of the vehicle; a controller connected to the electric unit and to a battery pack; a charge port to which the battery pack is connected; a throttle for regulating fuel supply to the engine through a carburetor, the throttle also being connected to the controller through a potentiometer; an ignition switch for operating a spark plug; a mode switch for connecting the throttle to the controller, such that when the mode switch is ON and the ignition switch is OFF, the engine is non-operative and the signal from throttle runs the electric unit through the controller, the power for the electric unit being derived from the battery pack through the controller; and such that when the mode switch is OFF and the ignition switch is OK the engine is started with the aid of a cranking mechanism, when the clutch automatically disconnects the engine from the transmission system, the speed of the engine increasing gradually coupling the clutch to the wheel through the transmission system and such that when both the mode switch and the ignition switch are on, the throttle operates the engine through carburetor and electric unit through the controller whereby both the power from the electric unit and the power from the engine through the transmission system reach the wheel.

This invention will new be described with reference to the accompanying drawings which illustrate by way of example and not by way of limitation a few embodiments thereof
Fig. 1 illustrating the first embodiment of this invention relating to a power train for a two wheeled automobile
Fig. 2 illustrating the fourth embodiment of the invention wherein the electric unit is moved from the hub of the wheel W and is part of the transmission system T after the clutch C with all other operations remaining the same as the previous embodiments.
Fig. 3 illustrating the fifth embodiment of this invention wherein the cranking mechanism CM consists of an electric starter motor SM to crank the engine 2E or 4E with all other operations remaining the same as in the previous embodiments.
Fig. 4 illustrating the sixth embodiment of this invention wherein the clutch C, the spark plug SP and the cranking mechanism CM is automatically operated using controller Cr. With other operations remaining the same as in the other embodiments, this invention can be used as a parallel hybrid system to optimise the IC engine operation whenever the engine is ON.
Figure I shows the first embodiment on the Invention where" it is conceived as a duel source powertrain for two-wheeled automobile with minimum number of parts. The internal combustion engine 2E transmits the power through the clutch C1 The engine 2E is a two-stroke engine with minimum number parts and hence light weight. The clutch C is conceived here to be a centrifugal clutch with fly mass F and drum D with engine 2E connected to fly mass F and drum D connected to the transmission T. The centrifugal clutch C allows an automatic operation with minimum number of parts disconnecting the engine 2E from transmission T when the electric motor alone is active. Transmission T consists of any known reduction mechanisms such as gear drives, chain drives, belt drives etc., or any combination of these. The transmission T connects the drum D to the Wheel W. In this embodiment the electric Unit MG is placed at the hub of the wheel W directly driving the wheel. The battery pack BP is connected to the controller Cn and the charge port CP using harness H. Also the controller Cn is connected to the electric Unit MG using harness H. The throttle input Tr from the driver is given to the engine 2E
through a carburetor Cr using cable Cb. The throttle input Tr is also connected to the controller Cn using potentiometer P. Transmission T also consists of a engine cranking mechanism CM with a lever L connected to the engine 2E using any known reduction mechanisms such as gear, chain or belt. The lever L can be hand operated or leg operated. An ignition switch IS is used to operate the spark plug SP of the engine 2E. A mode
switch MS is used to connect the throttle Tr to the controller Cn.
When the mode switch MS is on and ignition switch IS is off, the engine 2E is not operating and the signal from throttle Tr will run the electric unit MG through the controller Cn. The power to drive electric unit MG is derived from battery pack BP through the controller Cn; When the mode switch MS is off and ignition switch IS is on, the engine 2E is started using the cranking mechanism CM. During engine cranking the clutch C automatically disconnects the engine 2E from the transmission T due to low speed of idling. Based on the driver input at throttle Tr through the carburetor Cr, the speed of engine 2E increases gradually coupling the fly mass F and the drum D, hence connecting the engine 2E to the wheel W through the transmission T. When both the mode switch MS and ignition switch IS are on, the throttle Tr operates the engine 2E

through carburetor Cr and electric unit MG through the controller Cn. In such a case both the power from electric unit MG and the power from engine 2E through transmission T reach the wheel W. When the battery runs out of charge it can be recharged through the charging port CP.
The second embodiment of the invention where the clutch C is not a centrifugal clutch but any known mechanically operated clutch such as multi-plate wet clutch, dry clutch or electromagnetic clutch. With all other functioning of- the powertrain system remaining same the clutch operation in this embodiment can be either manual or automated using mechanisms.
The third embodiment of the invention where the engine 2E is replaced with 4E a four-stroke engine with all other operations remaining as in first or second embodiment. Even though the number of parts, cost and weight of the engine 4E is higher it gives the benefit of increased fuel economy during the internal combustion engine operation.
Figure 2 shows the fourth embodiment of the invention where the electric unit is moved from the hub of the wheel W and is part of the transmission T after the clutch C, With all other operations remaining same as the previous embodiments.
Figure 3 shows the fifth embodiment of the invention where the cranking mechanism CM consists of a electric starter motor SM to crank the engine 2E or 4E with all other operation remaining same as in previous embodiment.
Figure 4 shows the sixth embodiment of the invention where the clutch C, spark plug SP and the cranking mechanism SM is automatically operated using controller Cr. With the other operation remaining same as the other embodiments invention can be used as a parallel hybrid system to optimize the IC engine operation whenever the engine is on.

We Claim:
1. A dual power train for a motor vehicle comprising an internal
combustion engine transmitting power through a clutch
connected to a transmission system; an electric unit for driving
a wheel of the vehicle; a controller connected to the electric unit
and to a battery pack; a charge port to which the battery pack is
connected; a throttle for regulating fuel supply to the engine
through a carburetor, the throttle also being connected to the
controller through a potentiometer; an ignition switch for
operating a spark, plug; a mode switch for connecting the
throttle to the controller, such that when the mode switch is ON
and the ignition switch is OFF, the engine is non-operative and
the signal from throttle runs the electric unit through the
controller, the power for the electric unit being derived from the
battery pack through the controller; and such that when the
mode switch is OFF and the ignition switch is ON, the engine
is started with the aid of a cranking mechanism, when the
clutch automatically disconnects the engine from the
transmission system, the speed of the engine increasing
gradually coupling the clutch to the wheel through the
transmission system and such that when both the mode switch
and the ignition switch are on, the throttle operates the engine
through carburetor and electric unit through the controller
whereby both the power from the electric unit and the power
from the engine through the transmission system reach the
wheel.
2. A dual power train as claimed in Claim 1 wherein the engine is
of the two stroke type.
3. A dual power train as claimed in Claim 1 wherein the engine is
of the four stroke type.
4. A dual power train as claimed in Claim 1 or Claim 2 wherein
the clutch is of the centrifugal type.
5. A dual-power train as claimed in Claim 1 or Claim 2 wherein
the clutch is of the non-centrifugal type.
6. A dual power train as claimed in any one of the preceding
Claims wherein the cranking mechanism has a lever for
cranking the engine.

7. A dual power train as claimed in any one of the preceding
Claims wherein the cranking mechanism consists of an electric
starter motor.
8. A dual power train for a motor vehicle substantially as
described with reference to, and as illustrated in. the


Documents:

1952-CHE-2006 CORRESPONDENCE OTHERS.pdf

1952-CHE-2006 CORRESPONDENCE PO.pdf

1952-che-2006 description (complete) 21-07-2009.pdf

1952-che-2006_abstract.pdf

1952-che-2006_claims.pdf

1952-che-2006_correspondence-others.pdf

1952-che-2006_description-complete.pdf

1952-che-2006_drawings.pdf

1952-che-2006_form1.pdf

1952-che-2006_form18.pdf

1952-che-2006_form26.pdf


Patent Number 241502
Indian Patent Application Number 1952/CHE/2006
PG Journal Number 29/2010
Publication Date 16-Jul-2010
Grant Date 08-Jul-2010
Date of Filing 25-Oct-2006
Name of Patentee TVS MOTOR COMPANY
Applicant Address POST BOX NO. 4, HARITA, HOSUR 635109
Inventors:
# Inventor's Name Inventor's Address
1 MOHAN GANGADURAI MEMBER R&D, TVS MOTOR COMPANY, POST BOX NO.4, HARITA, HOSUR 635109
2 SRINATH GOPINATH MEMBER R&D, TVS MOTOR COMPANY, POST BOX NO.4, HARITA, HOSUR 635109
PCT International Classification Number H02P 9/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA