FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See Section 10; rule 13)
TITLE OF THE INVENTION
Integrated Endurance test rig for combination switch Wash Wipe, Lighting and Hazard warning Function.
APPLICANTS
TATA MOTORS LIMITED, an Indian company
having its registered office at Bombay House,
24 Homi Mody Street, Hutatma Chowk,
Mumbai 400 001 Maharashtra, India
INVENTORS
Mr. Uday Shankar Sambare
Indian national
of TATA MOTORS LIMITED,
An Indian company having its registered office
at Bombay House, 24 Homi Mody Street, Hutatma Chowk,
Mumbai 400 001 Maharashtra, India
&
Mr. Amol Bhaidas Ramole
Indian national
of JAYEM AUTOMOTIVE LTD,
An Indian company having its registered office
at No.2, Ondipudur Road, Singanallur,
Coimbatore, - 641005, Tamilnadu, India
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner
in which it is to be performed

FIELD OF INVENTION
The invention relates to Integrated test rig for Combination switch Wash Wipe, Lighting and Hazard warning function and more particularly to Endurance test rig for validating Wash Wipe, Lighting and Hazard warning function.
BACKGROUND OF INVENTION
A wash wipe and lighting function are two different functions of a combination switch. The wash wipe and lighting can be performed by rotating the left hand side (LHS) stalk and right hand side (RHS) stalk of the combination switch respectively, a rotary movement of the stalk is required to perform the function. A hazard warning function can be performed by pushing and pulling the lever knob of combination switch, a linear movement of the lever is required to perform the function. The conventional endurance testing for wash wipe and lighting function was performed manually i.e. by rotating the stalk by hand for 50000 and 60000 times respectively. The hazard warning function endurance used to be done on separate automated test rig for 20000 cycles. The following limitations were observed in the above methods of testing
1) Vehicle mounting condition of the combination switch was not taken into consideration while simulating the endurance test.
2) As switch was manually operated, operating forces use to vary from person to person and time to time. The combination switch was not being tested at maximum permissible forces (testing at worst condition).
3) Possibility of errors/mistakes in capturing the failures of the combination switch.
4) Possibility of error in counting of number of endurance cycles.
5) Skilled manpower required to perform, monitor and record the test results.
6) Testing time of combination switch was high as each function could not be tested simultaneously.
OBJECT OF THE INVENTION
The main objective of the present invention is to obviate the above mentioned drawbacks.

Another object of the invention is to provide the test rig capable of simulating vehicle conditions, which conducts endurance test of combination switch wash wipe, lighting and hazard warning function, simultaneously. Yet another objective of the present invention is to validate the component for the targeted endurance cycles under criterion of customer usage and provide the method of failure simulation which improves the product life.
SUMMARY OF THE INVENTION
The various embodiments of the present invention provide an integrated endurance test rig. The test rig comprises a rigid frame. A main-mounting plate is provided on said rigid frame for mounting a combination switch. A first and second side-mounting plate is provided on said rigid frame for mounting first motor and second motor. A third mounting plate is provided for mounting an electric actuator for operating hazard warning lever of said combination switch. A first gripper for coupling with a wash wipe stalk of said combination switch towards one end and other end coupled to said first motor to perform wash wipe function. A second gripper for coupling with said lighting stalk of said combination switch towards one end and other end coupled to said second motor to perform lighting function and a programmable logic controller (PLC) and an electric bulb load powered by power supply unit to simulate vehicle electric load.
The combination switch coupled to said main mounting plate is inclined at an angle equal to the angle of mounting of combination switch as in the vehicle. When the power supply unit is switched on said PLC monitors the input signals, reads the program in the central processing unit, processes the data and sends the output signal to said first and second motors. The PLC controls the direction and angle of rotation of said first motor, second motor and electric actuator. The PLC includes a counter for counting the number of endurance cycles for wash wipe, lighting stalk and a hazard warning function separately. The torque required for rotation of said wash wipe stalk and light stalk is can be controlled and set to a maximum level by varying the input voltage of said first and second motor and similarly a push and pull force to operate said hazard warning lever is controlled and set to maximum position by varying the input voltage and spring force of the

actuator. On receiving power supply the piston of said actuator moves to top dead position which in turn pushes the lever down and after a preprogrammed time said PLC cuts off the power supply to said actuator and due to spring action, the piston of said actuator travels back to bottom dead position thereby pulling the hazard warning lever back to initial position.
One endurance cycle for wash wipe function comprises of clockwise rotation of wash wipe stalk from OFF to LOW to HIGH position and then rotating the wash wipe stalk in anticlockwise direction from HIGH to LOW to OFF position with specified time delays at each position as per requirement. One endurance cycle for lighting function comprises of clockwise rotation of lighting stalk from OFF to PARK to HEADLAMP position and then rotating the light stalk in anticlockwise direction from HEADLAMP to PARK to OFF position with specified time delays at each position as per requirement.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. I shows the schematic diagram of an integrated endurance test rig for combination switch wash wipe, lighting and hazard warning function, according to present invention.
DETAILED DESCRD7TION OF THE INVENTION
Referring now to the drawings wherein the showings are for the purpose of illustrating a preferred embodiment of the invention only, and not for the purpose of limiting the same
An integrated endurance test rig for combination switch wash wipe, lighting and hazard warning function according to present invention is as show in FIG. 1. The test rig comprises a rigid frame 1 to mount structures and fix the same to the ground. A combination switch is 12 fixed to a main mounting plate 11, which is inclined at an angle equal to the angle of mounting of combination switch 12 as in the vehicle and fixed to the bottom rigid frame 1. A first motor 2 and a second motor 3 is mounted on a first side-mounting plate 4 and a second side-mounting plate 5. The first and second side-mounting plate is attached to the rigid frame 1.

A first motor 2 and second motors 3 are coupled to the first gripper 7 and second gripper 8 respectively. The first gripper 7 is clamped the wash wipe stalk 9 of the combination switch 12 and the second gripper 8 clamped with the lighting stalk 10 of the combination switch 12. The rotation of first motor 2 and second motor 3 rotates first gripper 7 and second griper 8 which in turn, rotates both the combination switch stalks to perform the wash wipe and lighting functions. An electric actuator 13 is mounted on a third mounting plate 14 and is aligned such that a piston 15 of actuator 13 pushes and pulls the hazard warning lever 16 of combination switch 12. A D.C. power supply unit 17 supplies power to the Programmable Logic Controller 19 and electric bulb load 18 to simulate vehicle electrical load. The PLC 19 controls the direction and angle of rotation of first motor 2, second motor 3 and the electric actuator 13. A counter feature in the PLC 19 is also used for counting the number of endurance cycles for each function separately.
The wash wipe stalk 9 of the combination switch 12 performs the wipe wash function. It has 3 operating position viz. OFF, LOW and HIGH. One endurance cycle for wash wipe comprises of clockwise rotation of wash wipe stalk 9 from OFF to LOW to HIGH position and then rotating the LHS stalk in anticlockwise direction from HIGH to LOW to OFF position with specified time delays at each position as per requirement. The lighting stalk 10 of the combination switch 12 performs the Lighting function. It has 3 operating position viz. OFF, PARK and HEADLAMP. One endurance cycle for lighting function comprises of clockwise rotation of lighting stalk 10 from OFF to PARK to HEADLAMP position and then rotating the lighting stalk 10 in anticlockwise direction from HEADLAMP to PARK to OFF position with specified time delays at each position as per requirement.
The present test rig performs both the above functions simultaneously. When power supply unit 17 is switched on, the PLC 19 monitors the input signals it receives, reads the program in the CPU, processes the data and sends the output signal (to the both D.C. motors). On receiving the power, the motor rotates in clockwise direction (Logic programmed in PLC) and the angle of rotation of the motor for each position of the switch is controlled by a pre fixed time in the PLC

(19). The TIMER feature of the PLC 19 is used to control the angle of rotation of the motor. The output shaft 6 of the motor is coupled to the gripper made of rubber via nut bolt mechanism. This causes the gripper to move in clockwise direction which in turn rotates the stalk of the combination switch to a pre determined angle (equal to LOW / PARK switch position). The same sequence repeats till the stalk rotates to HIGH / HEADLAMP position. At this position, the preprogrammed TIMER signal reaches the PLC 19, it then sends power (reverse polarity) to the D.C.motor such that now the motor rotates in anticlockwise direction, rotating the stalk back to the initial position.
The construction and working, described above is same for wash wipe stalk and lighting stalk of the combination switch 12.The torque required for rotation of the stalk can be controlled and set to maximum level (worst testing condition) by varying the input voltage of the D.C.motor.
Endurance cycle of Hazard warning function comprises of pushing the hazard lever 16 down and then pulling it up. In the present test rig, hazard warning endurance is done by means of an electric actuator. When power supply unit 17 is switched on, the PLC 19 monitors the input signals it receives, reads the program in the CPU, processes the data and sends the output signal (to the both D.C. motors). On receiving the power, the electric actuator piston 15 moves to top dead position. The piston of the actuator 15 is coupled to the lever 16 of Hazard warning function, which in turn pushes the lever 16 down. After the preprogrammed time is over, the PLC 19 cuts off the power of the actuator. Due to spring action, the piston 15 of the actuator travels back to bottom dead position, thereby pulling the hazard warning lever back to initial position. The push and pull force to operate the lever can be controlled and set to maximum position (worst testing condition) by varying the input voltage to the actuator and the spring force of the actuator.
The electrical load bank 18 is connected as per specification required at each position of the combination switch. The same electric bulb load 18 serves the purpose of visual indication of make and break of moving contacts at each position of the combination switch 12.
Advantages:

• With this test rig, endurance test of combination switch Wash wipe, Lighting and Hazard warning function can be done simultaneously as in vehicle conditions.
• Automation of test rig permits us to test the combination switch at maximum specified forces (testing at worst condition).
• Optimisation of skilled manpower and reduction in man hours achieved. Testing time has come down to 33% as 3 functions can be tested simultaneously. Development time of component reduced.
• Use of inbuilt Counter feature of the PLC for counting the endurance cycle for each function separately has eliminated the possibilty of counting error, also resulting in saving of manpower.
• This test rig can provide quick, fairly accurate results and require no special testing skills and/or high investments. Thus, effectively reducing overhead cost of testing.
• This. test rig can be used for wide range of vehicles (in terms of performance level) without requiring any major change except may be load cell capacity.
The foregoing description is a specific embodiment of the present invention. It should be appreciated that this embodiment is described for purpose of illustration only, and that numerous alterations and modifications may be practiced by those skilled in the art without departing from the spirit and scope of the invention. It is intended that all such modifications and alterations be included in, so far as they come within the scope of the invention as claimed or the equivalents thereof.

We claim
1. An integrated endurance test rig, comprising;
a rigid frame;
a main-mounting plate provided on said rigid frame for mounting a combination
switch;
a first and second side-mounting plate provided on said rigid frame for mounting
first motor and second motor;
a third mounting plate for mounting an electric actuator for operating hazard
warning lever of said combination switch;
a first gripper for coupling with a wash wipe stalk of said combination switch
towards one end and other end coupled to said first motor to perform wash wipe
function;
a second gripper for coupling with said lighting stalk of said combination switch
towards one end and other end coupled to said second motor to perform lighting
function;
a programmable logic controller (PLC) and an electric bulb load powered by
power supply unit to simulate vehicle electric load.
2. The test rig according to claim 1, wherein said combination switch coupled to said main mounting plate is inclined at an angle equal to the angle of mounting of combination switch as in the vehicle.
3. The test rig according to claim 1, wherein one endurance cycle for wash wipe function comprises of clockwise rotation of wash wipe stalk from OFF to LOW to HIGH position and then rotating the wash wipe stalk in anticlockwise direction from HIGH to LOW to OFF position with specified time delays at each position as per requirement.
4. The test rig according to claim 1, wherein one endurance cycle for lighting function comprises of clockwise rotation of lighting stalk from OFF to PARK to HEADLAMP position and then rotating the light stalk in anticlockwise direction from HEADLAMP to PARK to OFF position with specified time delays at each position as per requirement.

5. The test rig according to claim 1, wherein when said power supply unit is switched on said PLC monitors the input signals, reads the program in the central processing unit, processes the data and sends the output signal to said first and second motors.
6. The test rig according to claim 1, wherein said PLC (19) controls the direction (clock wise/anti-clock wise) and angle of rotation of said first motor, second motor and electric actuator (13).
7. The test rig according to claim 1, wherein said PLC having a counter for counting the number of endurance cycles for wash wipe, lighting stalk and a hazard warning function separately.
8. The test rig according to claim 1, wherein said first motor and second motor is coupled to first gripper and second gripper by an output shaft through a nut bolt mechanism.
9. The test rig according to claim 1, wherein a torque required for rotation of said wash wipe stalk and light stalk can be controlled and set to a maximum level by varying the input voltage of said first and second motor and similarly a push and pull force to operate said hazard warning lever is controlled and set to maximum position by varying the input voltage and spring force of the actuator.
10. The test rig according to claim 1, wherein on receiving power supply the
piston of said actuator moves to top dead position which in turn pushes the lever
(16) down and after a preprogrammed time said PLC (19) cuts off the power
supply to said actuator and due to spring action, the piston of said actuator travels
back to bottom dead position thereby pulling the hazard warning lever back to
initial position.