FORM - 2
THE PATENTS ACT, 1970
( 39 of 1970 )
PROVISIONAL / COMPLETE SPECIFICATION SECTION 10
TITLE

“ELECTRICALLY OPERATED CENTER STAND FOR TWO WHEELED VEHICLES "

APPLICANT
BAJAJ AUTO LIMITED, an Indian Limited Company,
of Akurdi, Pune 411 035, Maharashtra, India
The following specification particularly describes the nature of the invention and the manner in which it is to be performed

This invention relates to an electrically operated center stand for two wheeled vehicles such as scooterettes, scooters and motorcycles. These types of vehicles are termed as "vehicles" in this specification. The present invention particularly is related but not limited to the stand mounted on the engine of these vehicles.
Center stand is an essential part of any vehicle. The stand is in the form of a fabricated structure having two legs of tubes or rods welded with sheet metal brackets and other parts. The stand is attached to the chassis symmetrically. The stand is held in retracted position with the help of one or two springs when the vehicle is in running condition. When the rider decides to park the vehicle, he shifts the stand to near vertical position by applying force at the end of the stand and pulls the vehicle backwards by holding the handle bar and other rear part of vehicle, so that the central portion of the vehicle gets supported by the stand. Either the front or rear wheel of the vehicle in this condition is lifted and the whole vehicle is fully supported by the stand and one (rear or front) wheel is free. The stand is pivoted either on the chassis or engine depending on the configuration of the vehicle and the packaging needs. The system of mounting of the stand and its operation is well known.
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The application of force at the end of the stand by foot and pulling the vehicle backwards (by holding handle bar by one hand and grab handle or other part by other hand) is a manual operation to be done by the rider. This is cumbersome and there is a chance of tilting of the vehicle, when proper care to balance the vehicle is not taken. This is particularly difficult for the ladies. Various methods of carrying out the operation automatically have been tried. One of the methods known earlier is to operate the stand electrically, by providing an electric motor operated by the vehicle battery. For an example, US Patent No. 5,100,164 dated March 31 1992 discloses the stand operated by an electric motor.
In order to avoid above difficulties, we have invented a system of center stand, which is electrically operable by the rider using the starter motor of the vehicle.
The objective of the present invention is to provide an electrically operated center stand so as to allow the rider of the vehicle to put the stand into extended position by simply actuating a switch and without having to exert any effort.
Yet another objective of the present invention is to use electrical starter motor employed to start engine of vehicles.
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The invention will now be explained with reference to the accompanying drawings, wherein
Fig. 1 illustrates an engine mounted center stand of the prior art.
Figs 2a and 2b illustrate a typical starter motor operated center stand according to the invention, in assembled condition.
Fig.3 illustrates details of typical starter motor operated center stand according to the invention.
Fig.4 illustrates a block circuit diagram of typical starter motor operated center stand according to the invention.
Figs 5a and 5b illustrate an embodiment of typical starter motor operated center stand according to the invention in assembled condition.
Fig.6 illustrates details of an embodiment of typical starter motor operated center stand according to the invention.
Fig.7 illustrates a block circuit diagram of an embodiment of
typical starter motor operated center stand according to the invention.
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An electrically operated center stand according to the present invention essentially comprises of a center stand (3) having two lugs (3a and 3b), a stand switch (8), a starter switch (9), a limit switch (10), a starter motor (6) having a starter motor gear (11), a first spur gear (12), driven gear (7), an ignition switch (Ign), a one way clutch engine (13), an output shaft (15), a second spur gear (16), a third spur gear (17), a gear for stand (18), a clutch for stand (19), a pivot pin (20), a stand tube (21), a pin for spring (22), a rivet for spring (23), a bracket for stand RH (24), a bracket for stand LH (25), a lock pin (26), a spring (27), a bracket stand mounting (28), a stopper pin (29), a starter relay (SRI), a brake switch rear(BSl), a brake switch front (BS2), a NC relay (SR2), a first NO relay (SR3) and a second NO relay (SR4).
With reference to Figure 1, the stand (3) is pivotally mounted on engine (2). The said stand is in retracted position when the vehicle (1) is in moving condition. When the rider decides to park the vehicle, he applies foot force as shown in the direction of F and rotates the stand around its pivot. As the said stand touches the ground, the rider pulls the vehicle backside by hand force applied at grab handle (4) and grip handle bar (5) while maintaining the foot force. The said stand then takes angular position, say 0, and the vehicle rests on two lugs of the stand. This system of stand operation is well known and does not need detailed explanation.
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With reference to figures 2a, 2b and 3, the starter motor (6) operable through ignition switch (Ign) by both stand switch (8) and starter switch (9), is provided with a starter motor gear (11), which is in mesh with gear first spur gear (12). Further, gear train consisting of second spur gear (16), which is integral with gear (7), third spur gear (17), assembled rotatably and externally on the engine (2) and gear for stand (18), is provided. One way clutch engine (13) is provided on out put shaft (15), which is a common shaft for the said gear (16) and sprocket (14a) for chain (14). The said gear for stand (18) is fixed to the pivot pin (20), which passes through stand tube (21) and is fixed to the said pivot pin (20) with lock pin (26). The stand (3) is a welded structure of two legs (3a and 3b), made of steel tubes or rods, one end of each leg is welded to the stand tube (21) with predetermined angular position and the other ends are provided with bracket for stand RH (24) and bracket for stand LH (25) on legs (3b) and (3a) respectively. The welded structure is further provided with bracket stand mounting (28) and a stopper pin (29) at predetermined positions. A clutch for stand (19) is provided on the said pivot pin (20). The said leg (3b) is welded at predetermined position with rivet for spring (23) which holds one end the spring (27) and the other end of the said spring is engaged to the pin for spring (22) fixed on the engine. Further, a limit switch (10) is provided at predetermined position.
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As illustrated in Fig.4, the ignition switch (Ign) is provided with two separate positions one for starting the engine (ON) and other for stand mode. When the said ignition switch is in ON position and said starter switch is actuated, the starter relay (SRI) is energized through the brake switch (BS1 or BS2). The NC relay (SR2) in this condition is in normally closed mode thereby connecting the engine ground to battery negative enabling the said starter motor to run in the direction suitable for starting the engine (Dl). When the said ignition switch is in stand mode position, the first NO relay (SR3) and second NO relay (SR4) are energized through the stand switch (8). This enables the starter motor in opposite direction (D2). The rotation in Dl direction is transmitted to engine through first spur gear (12), gear (7), one way clutch (13) and output shaft (15), conventionally. The opposite rotation in D2 direction is transmitted to the stand as explained below. In this case the said one way clutch (13) does not allow the rotation to be passed on to the output shaft (15).
During rotation of starter motor (6) and starter motor gear (11) in D2 direction, the rotational movement of gear (7) is transmitted to gear for stand (18), through second spur gear (16) and third spur gear (17).
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The said gear for stand (18) being fixed to pivot pin (20), when gets rotated, rotates the stand from its retracted position to the position of touching the ground (ref fig.2) and then lifts the vehicle in the parked position. In order to avoid excessive movement of the stand beyond predetermined parked position, electrical supply to the starter motor is cuts off by a limit switch (10). While removing the vehicle from the parked position, the rider needs to push the vehicle forward by holding the bracket (25) by foot and moving the vehicle forwardly by holding the vehicle at handle bar (5) and grab handle (4), which is done conventionally.
In the above description, the gear train consisting of the parts (11), (12) and (7) is illustrated inside the engine. As an embodiment of the present invention, it is possible to provide the gear train from outside the engine which is described below.
An electrically operated center stand according to the embodiment of the present invention essentially comprises of a center stand (3) having two lugs (3a and 3b), a stand switch (8), a starter switch (9), a limit switch (10), a starter motor (6a) having first worm gear (33), a second worm wheel (32), first spur gear (31), a second spur gear (30), a ignition switch (Ign), a third spur gear (17), a gear for stand (18), a clutch for
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stand (19), a pivot pin (20), a stand tube (21), a pin for spring (22), a rivet for spring (23), a bracket for stand RH (24), a bracket for stand LH (25), a lock pin (26), a spring (27), a bracket stand mounting (28), a stopper pin (29) a starter relays (SRI) and (SR2), a brake switch rear . (BS1), and a brake switch front (BS2).
As illustrated in figure 6, the system works in the identical manner wherein the gear train consists of parts (33), (32), (31), (30) and (18).
With reference to figure 7, according to an embodiment of the present invention, when the said ignition switch is in ON position, and said starter switch is actuated, the starter relay (SRI) is energized through the brake switch (BS1 or BS2). The said starter motor terminal (A 1) gets positive supply through NO contact of relay (SRI) and said starter motor terminal (A2) gets connected to ground through NC contact of relay (SR2) enabling the said starter motor to run in the direction suitable for starting the engine (Dl). When the said ignition switch is in stand mode position, and said stand switch pressed the said starter motor terminal (A2) gets positive supply through NO contact of relay (SR2) and terminal (A 1) gets connected to ground through NC contact of relay (SRI), which enables the starter motor to run in opposite direction (D2). The opposite rotation in D2 direction is transmitted to the stand as explained above.
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In the description given above, the gear trains indicated outside of the engine are necessarily to be covered by suitable covers for safety which are within the scope of the invention.
The description stated above does not describe the exact locations of various gear shafts, one way clutches, locking pin arrangement etc. However, such locations are the decisions of designers and depend upon parameters like the shape and configuration of the engine, location, orientation and electrical characteristics of the starter motor, distance between the stand pivot and starter motor axis, torque/speed characteristics of starter motor and load/speed requirements of stand etc.
The description stated above describes electrically operated engine mounted stand. It is however possible to operate chassis or frame mounted stands providing a flexible transmission between the starter motor and the stand pivot. The transmission in this case has to be retained as flexible because depending on the load condition of the vehicle, the distance between the stand pivot and the axis of the starter motor varies since the engine is normally swinging type in vehicles. Such systems are well within the scope of this invention.
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In the descriptions stated above and illustrated, various gear trains have been explained. It is, however, possible to adopt different types of transmission systems, like helical gears, bevel gears, worm and worm wheel, rack and pinion system etc, which are well within the scope of this invention.
An electrically operated center stand for two wheeled vehicles as described herein and and illustrated in the accompanying drawings and having variations and modifications well within the knowledge of a person skilled in the art without deviating from scope of the invention are within the scope of the present invention and its embodiment.
Dated this 7th day of July 2004.

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