Control Unit

Field of the Invention:

The present invention relates to a control unit for a two wheeler.

Background of the Invention:
Generally in an "Automated manual transmission" (AMT) gear shifting is achieved automatically without the driver interacting physically with gear and clutch actuation mechanism. The gear and clutch shifting is performed by an electronic control unit (ECU) actuating different actuators. This ECU unit is termed as AMT control unit.

Internal combustion engine which produces input power for the AMT unit is controlled by a separate ECU which is termed as engine control unit. The said engine control unit controls various output depending on the engine system configuration. If the engine is a carbureted engine, the engine control unit controls spark timing, secondary air path control valve and chock control valve. The output list is not limited to the above mentioned outputs. If the engine is fuel injected vehicle, the engine control unit controls spark timing, fuel quantity, fuel pump duty cycle, idle speed control valve, electronic throttle control and like. The output list is not limited to the above mentioned outputs only.

The said AMT control unit and engine control unit is required to work in synchronous manner. The main reason being, both the ECU controls the output power at the wheel. Any sudden change of wheel power can affect the drivability of the vehicle. If both the ECU does not synchronize, there is a good chance of compromise in drivability of the vehicle. Typically, both the units share data through a communication bus and there is a need for robust communication for fast data sharing between the two said control unit. Chances of duplication of input signal conditioning circuit for certain functionally critical sensors. More complexity of the supervisory control algorithm for controlling the wheel power and finally there will be an increase of cost due to use of two numbers of independent ECUs.

Summary of the Invention:

An object of the present invention is to provide an integrated unit with AMT control functionality and engine control functionality.

Another object of the present invention is to provide an integrated unit with AMT control which acts as a unit signal condition interface for various sensors for engine and AMT control functionality.

Another object of the present invention is to provide an integrated unit with safety critical applications which are required for two wheeled vehicle.

Yet another object of the present invention is to provide an integrated unit with engine start stop functionality.

Further object of the present invention is to provide an integrated unit which is suitable for different configurations for engine and transmission unit.

Further object of the present invention is to provide an integrated unit with AMT control functionality and engine control functionality thereby eliminating the requirement of robust communication for data sharing.

Yet another object of the present invention is to provide a cost effective control unit with AMT control functionality and engine control functionality.

Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

Brief Description of the Drawings:

The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein

Figure 1 shows a conventional scooter type vehicle.

Figure 2 shows a control unit according to the present invention.

Detailed Description of the Drawings:

The present invention now will be described more fully hereinafter with different_embodiments. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather those embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the invention to those skilled in the art.
The present invention is illustrated with a scooter type vehicle. The illustrated scooter type vehicle comprises a so called low floor board type vehicle and the term scooter as used herein should not be inferred to restrict the maximum speed, the displacement amount or the like of the vehicle. Moreover the present invention is not limited to a scoter type vehicle and certain features, aspects and advantages of embodiments of the present invention can be used with other types of two wheelers such as motorcycle, step thru and the like.

With reference to Figure 1,1 denotes a front wheel, 2 denotes a front fork, 3 denotes a front fender, 4 denotes a front cover, 5 denotes a leg shield made of resin or metal, 6 denotes a handle bar cover, 7 denotes a headlight, 8 denotes a handle bar ,17 denotes a rear fender and 18 denotes tail lamp.
The centre of the body forms a low floor board 9 for functioning as a part for putting feet and a under cowl 10 which is located below the rider's seat and covers at least a part of the engine, The under cowl is made up of metal or resin. The under cowl is hinged to the seat 11. A utility box 12 opens from the rear end to hinged portion. The utility box 12 is provided under the seat extending longitudinally of a vehicle body and the inside of the utility box has a large capacity so that a large article can be housed. A
main frame 14 extended along the center of the body before and behind and made of a metallic pipe and is provided under the floor board 9. A swing type power unit 13 is coupled to the rear end of the main frame 14. A rear wheel 15 is supported on one side of the rear end of the swing type power unit 13. The swing type power unit 13 is suspended in the rear of a body frame.

The side covers 16 both on left and right sides, covers the utility box 12 and other parts of the vehicle, thereby providing a good appearance to the vehicle.

According to one embodiment of the present invention and referring to Figure 2, the inputs used for engine control function (depending on the engine configuration) in integrated control unit 201 comprises: engine speed and position sensor signal, intake air temperature sensor signal, engine cylinder head temperature sensor signal, transmission oil temperature sensor signal, throttle position sensor signal, intake air flow sensor signal, manifold air pressure sensor signal, knock sensor signal, lambda sensor signal, fuel selection signal, vehicle speed sensor signal, automatic economy drive mode select signal, automatic sporty drive mode select signal, manual drive mode select signal, and cam shaft signal.

Inputs used for AMT control function, depending on the refinement of control software requirement in integrated control unit, comprises:

Engine speed sensor signal, Vehicle speed sensor signal,

Transmission output shaft speed sensor signal,
Gear position sensor signal,
Clutch position sensor signal,
Gear down select switch signal,
Gear up select switch signal,
Brake position signal,
Automatic economy drive mode select signal,
Automatic sporty drive mode select signal, and
Manual drive mode select signal.

Inputs used for safety critical functions in the integrated controller unit comprises:

Seat occupancy sensor signal,
Vehicle tilt sensor signal, and
Side stand switch signal.

Inputs used for start stop functionality in the integrated controller unit comprises:

Throttle position sensor signal,
Brake position sensor signal,
Sear occupancy sensor signal, and
Vehicle speed sensor signal.
Outputs used for engine control functionality depending upon engine
configuration in integrated control unit comprises:
Fuel injector output, Spark timing output, Fuel pump output, Engine cooling fan output, Canister purge valve output, Idle speed control valve output, Secondary air input control valve, and Automatic chock control valve.

Outputs used for AMT control functionality in integrated control unit 201 comprises:
Gearshift actuator output,
Clutch shift actuator output,
Electronic throttle control actuator output, and
Secondary air path control actuator output.
Output used for Start stop functionality in integrated control unit is starter relay coil output.
The engine control functionality performs the following functions with the integrated control unit 201:
1st Function- Static and dynamic engine torque output according to the driver

command

2nd Function - Change of engine transient response according to manual driver

mode selection
3rd Function- Automatic change of engine transient response with the driver usage

style when automatic mode is selected

4th Function- Idle speed control for various engine load condition
5th Function- Engine torque damping during gear shift
6th Function- Knock control
7th Function- Closed loop emission control
8th Function- Engine Start/Stop functionality.

The AMT control functionality performs the following functions with the integrated control unit:

1st Function- Clutch launch control
2nd Function- Gear shift control according to the Gear Up/Down command in manual

mode drive
3rd Function- Automatic gear shift control in either Economy mode/Sporty mode

according to the driver mode selection
4th Function - Safety interlock function for unsafe gear shifting during vehicle turning
5th Function - Safety interlock function for unsafe gear shifting when driver is not occupied the seat.
6th Function- Safety interlock function for unsafe gear shifting when driver is not

removed the side stand of the vehicle.
There are several overlaps between the above mentioned functionality of engine control and AMT control. The overlaps are mentioned as below:

1st function of AMT control overlaps with 1st,2nd ,3rd ,4th ,6th and 7th function of engine control,
2nd function of AMT control overlaps with 1st,2nd ,4th ,5th ,6th and 7th function of engine control, and
3rd function of AMT control overlaps with 1st,3rd ,4th ,5th ,6th and 7th function of engine control

In the said integrated control unit 201, overlap of the functionalities is realized using less system resources then the configuration having two independent ECUs.

The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such
modifications as would be obvious to one skilled in the art are intended to be included within the scope of the claims.

We Claim:

1. A control unit for automatic manual transmission equipped engine comprises:

an engine control functionality;

an automatic manual transmission control functionality;

a safety critical functionality; and

a start stop functionality;

wherein the above all functionalities are integrated in a single control unit.

2. The control unit as claimed in claim 1, wherein the automatic manual transmission control functionality input comprises: an engine speed sensor signal; a vehicle speed sensor signal; a transmission output shaft speed sensor signal; a gear position sensor signal; a clutch position sensor signal; a gear down select switch signal; a gear up select switch signal; a brake position signal; an automatic economy drive mode select signal; an automatic sporty drive mode select signal; and a manual drive mode select signal.

3. The control unit as claimed in claim 1, wherein the engine control functionality input comprises: engine speed and position sensor signal, intake air temperature sensor signal, engine cylinder head temperature sensor signal, transmission oil temperature sensor signal, throttle position sensor signal, intake air flow sensor signal, manifold air pressure sensor signal, knock sensor signal, lambda sensor signal, fuel selection signal, vehicle speed sensor signal, automatic economy drive mode select signal, automatic sporty drive mode select signal, manual drive mode select signal, and cam shaft signal.

4. The control unit as claimed in claim \, wherein the safety critical functionality input comprises: Inputs used for safety critical functions in the integrated controller unit comprises: Seat occupancy sensor signal, Vehicle tilt sensor signal, and Side stand switch signal.

5. The control unit as claimed in claim 1, wherein the start stop functionality input comprises: throttle position sensor signal, brake position sensor signal, seat occupancy sensor signal, and Vehicle speed sensor signal.

6. The control unit as claimed in claim 1, wherein the engine control functionality output comprises: fuel injector output, spark timing output, fuel pump output, engine cooling fan output, canister purge valve output, idle speed control valve output, secondary air input control valve, and automatic chock control valve.

7. The control unit as claimed in claim 1, wherein the automatic manual transmission functionality output comprises: gearshift actuator output, clutch shift actuator output, electronic throttle control actuator output, and secondary air path control actuator output.

8. The control unit as claimed in claim 1, wherein the start stop functionality output is starter relay coil output.