This invention relates to mechanical linkages for actuation of regenerative braking system in conjugation with mechanical braking for electric off-highway and construction vehicles/equipments, particularly Electric Tractors.
BACKGROUND/PRIOR ART
Due to farm mechanization in agriculture, off-highway vehicles like tractors are widely used in different agriculture operations. Conventionally, tractor has the independent braking system for each of the Rear wheels. For independent braking, there are two brake pedals:- one for left-hand (LH) side wheel and another for right-hand (RH) side wheel. Such type of braking is required to achieve the minimum turning radius, while doing farming by applying the brake on a single wheel independently while turning; at this instant, other wheel is free to move.
Conventional tractors have above mentioned type of braking system. Mechanical linkages are designed in such a way that latch of the brake pedals can be attached or detached anytime as per the requirement.
But in case of electric vehicles, two types of electronic braking are in practice:-
(1) Active Braking and (2) Passive Braking.

In Active Braking, when brake is pressed, it is sensed by a brake-potentiometer attached with brake pedal, and the request generated for braking is sent to drive motor controller, after getting the Active Braking request, it stops giving the power to the drive motor and drive motor works as generator to boost the battery power. This means, whenever the brake pedal is pressed, the drive motor will not power up the transmission i.e. motor will not move the vehicle.
While during Passive Braking, whenever the accelerator throttle pedal is released the controller stops giving power to the drive motor.
Now, in the case of electric tractor, there will be same requirement of independent braking for achieving the minimum turning radius. If the brake-potentiometer is installed in conventional manner like other electric vehicles, then it will not be possible to run the drive motor in case of independent pedal braking requirement.
For making turn and in need of minimum turning radius while doing farming, it is customary to use independent brake and also power up the tractor, which would have not been possible without this invention in Compact Electric Tractor.
OBJECTS OF THE INVENTION
The present invention is intended to provide a design solution so that we can install the brake-potentiometer in such a way that independent braking can be done and brake-potentiometer is only be actuated when both the pedals are pressed in latch locked condition; particularly in Electric tractors and other Electric off-highway vehicles.

Prime object of the instant invention is to provide novel mechanical linkages for actuation of regenerative braking system in conjugation with mechanical braking, to be operated by left and right brake pedals in electric tractors and other electric off-highway vehicles.
Another prime object of the instant invention is to provide such structural and functional arrangements in electric tractor that for making turn and in need of minimum turning radius while doing farming, said electric tractor is capable of using independent brake and simultaneously its drive motor gets powered-up.
Another object of the instant invention is to provide unique mechanical linkages of brake pedals in electric tractor to make left and right brakes work independently without actuating brake-potentiometer.
Another object of the instant invention is to provide such novel mechanical linkages in electric tractor and their method of operation thereof, so that the brake-potentiometer is provisioned only to actuate when both the brake pedals are pressed.
Another object of the instant invention is to provide a novel brake-potentiometer actuation mechanism in off-highway vehicles, particularly in electric tractors making turn and in need of minimum turning radius while doing farming.
At the outset of the description, which follows, it is to be understood that the ensuing description only illustrates a particular form of this invention. However, such a particular form is only an exemplary embodiment, without intending to imply any limitation on the scope of this invention. Accordingly, the description herein is to be

understood as an exemplary embodiment and teaching of the invention is not intended to be taken resthctively.
BRIEF DESCRIPTION OF THE INVENTION
The invention disclosed hereinbelow generally relates to mechanical linkages for actuation of regenerative braking system in conjugation with mechanical braking for electric off-highway and construction vehicles/equipments, particularly Electric Tractors.
According to this Invention, mechanical linkages are designed in such a way that brake-potentiometer should only get actuated when both the brake pedals are pressed. It was a challenge to invent unique linkages of brake pedals to make left-brake and right-brake work independently without actuating brake-potentiometer.
Brief description about the schematic drawings for illustrating the most preferred embodiment of the instant invention, particularly to be applied in Electric tractors:
Figure-1:- Schematic representation of the Brake-Potentiometer and Lever Assembly;
Figure 2:- Schematic representation of the Brake Pedals and Linkage Assembly;
Figure 3:- Schematic representation of the Left-Hand Side (LH) Brake Actuation;
Figure 4:- Schematic representation of the Right-Hand Side (RH) Brake Actuation;
Figure 5:- Schematic representation of initial Brake Position;
Figure 6:- Schematic view of both brake actuations.

In the schematic drawings included hereinbelow, structural/constructional or functional features of the mechanical linkage and its actuation mechanism, as the subject matter instant invention, are represented by the numeric references, as under:

Reference numeral used in drawings Particulars of structural/constructional or functional feature, schematically depicted in drawings enclosed in the instant specification
01 Brake-potentiometer mounted on a bracket
01a Bracket for mounting brake-potentiometer (01)
02 Actuating Lever
03 Clevis Link
04 Pivot Lever-Link
05 Bracket Assembly
04a Hinge pin, engaged with Bracket assembly 05, for holding and mobilizing the Pivot Lever plate or link 04.
06 Right-hand side Pedal (RH Pedal)
07 Left-hand side Pedal (LH Pedal)
08 LH pedal-pivot lug
09 RH pedal-pivot lug
10 Spring
11 Encircled region depicts the physical line-contact between surface of the Pivot Lever Plate 04 and at least one of the two pedal-pivot lugs, 08 and 09.
12 Encircled region depicts virtual or actual loss of physical line-contact between surface of the Pivot Lever Plate 04 and both of the pedal-pivot lugs, 08 and 09.
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Actuating Mechanism is explained and respective figures are shown below;
Figure no. 01 and 02 shows the brake subassembly with installation of brake-potentiometer. In figure 01, brake-potentiometer (01) is mounted on a bracket (01a) and the Input is connected with actuating lever (02). As already stated, motive of the design of this mechanism is to give the actuation to this lever (2) whenever both the Pedals (06) and (07) are actuated. Connecting clevis link (03) provides the actuation to the lever (02) when it is pushed by pivot lever-link (04). Said lever-link (04) is pivoted about a hinge pin (04a) and assembled on the Bracket Assembly (05). This pivot lever-link (04) is connected with a spring (10) which always tries to pull the lever-link (04). RH Pedal (06) and LH Pedal (07) are having RH pedal-pivot and LH pedal-pivot Lugs (08) and (09) respectively. LH pedal-pivot lug (08) and RH pedal-pivot lug (09) are having line contact (11) with lever-link (04) and always oppose said link (04) to be actuated until the pedals are pressed.
Left-Hand Side (LH) Brake Actuation:
Figure no. 03 & 04 shows the individual actuation of both the pedals (06) and (07). In Figure no. 03, LH brake actuation is shown where LH pedal (07) is pressed. In this figure it can be easily understand that after the actuation of the LH pedal (07), LH pedal-pivot lug (09) is rotated by some angle and has left the line contact with the pivot lever-link (04), but said pivot lever-link (04) is not actuating. This is because RH pedal-pivot lug (08) remains in line contact (11) with the said pivot lever-link (04) and therefore not allowing the said pivot lever-link (04) to move forward, thus restricting the actuation of link no (03) and (02). The same phenomenon happens in case of RH brake actuation.
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Right-Hand Side (RH) Brake Actuation:
In Figure no. 04, RH brake actuation is shown where RH pedal (06) is pressed. Again in this figure it can be easily understand that after the actuation of the RH pedal (06), RH pedal-pivot lug (08) is rotated by some angle and has left the line contact with the pivot lever-link (04) but said pivot link (04) is not actuating. This is because LH pedal-pivot lug (09) ) remains in line contact (11) with the said pivot lever-link (04) and therefore not allowing the said pivot lever-link (04) to move forward, thus restricting the actuation of link no (03) and (02).
Both Brake Pedals Actuation:
Figure no. 05 and 06 shows the initial and actuated position of both the pedals (06) and (07). When both the pedals are on their initial position, both pedal-pivot lugs (08) and (09) remain in line contact (11) with the said pivot lever-link (04) and they do not allow the pivot lever-link (04) to move forward and restrict the said pivot lever-link(04) in its vertical position similarly when they restrict the motion in independent braking.
When both the Pedals, (06) and (07), are pressed together, both the pedal-pivot lugs, (08) and (09), are rotated by some angle as shown in the Figure no. 06 and try to leave the line contact with pivot lever-link (04) simultaneously, as depicted by numeral 12 in Figure 6. Due to the pulling force of the spring (10), said pivot lever-link (04) actuates and is rotated by some angle as shown in the figure 6. When the pivot lever-link (04) actuates, it pushes the connecting link (03) linearly and ultimately gives the actuation to the Lever (02).
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ADVANTAGEOUS FEATURES OF THE PRESENT INVENTION
1) Solution to avoid braking complexity
2) Linkage solution for Independent Braking
3) Made possible of regenerative braking in Tractor
4) Best, Reliable and Compact Design
5) Easy to install
6) Cost effective
Although the present disclosure has been illustrated and described herein with reference to preferred embodiments and specific examples thereof, it will be readily apparent to those of ordinary skill in the art that other embodiments and examples may perform similar functions and/or achieve like results. All such equivalent embodiments and examples are within the spirit and scope of the present disclosure, are contemplated thereby, and are intended to be covered by the following claims.
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We claim:

Novel mechanical linkages for actuation of regenerative braking system in conjugation with mechanical braking in electric tractors and other electric off-highway vehicles; wherein said linkages mainly comprises major structural components as mentioned in following table:

01 Brake-potentiometer mounted on a bracket
01a Bracket for mounting brake-potentiometer (01)
02 Actuating Lever
03 Clevis Link
04 Pivot Lever-Link
05 Bracket Assembly
04a Hinge, engaged with Bracket assembly 05, for holding and mobilizing the Pivot Lever plate or link 04.
06 Right-hand side Pedal (RH Pedal)
07 Left-hand side Pedal (LH Pedal)
08 LH pedal-pivot lug
09 RH pedal-pivot lug
10 Spring
11 Encircled region depicts the physical contact between surface of the Pivot Lever Plate 04 and at least one of the two pedal-pivot lugs, 08 and 09.
12 Encircled region depicts loss of physical contact between surface of the Pivot Lever Plate 04 and both two pedal-pivot lugs, 08 and 09.

Linkages for actuation of braking system, as claimed in claim 1, wherein said linkages mainly comprise of brake sub-assembly and the brake-potentiometer (01) installation; wherein the said mechanical linkages is characterized in its provision to be operated in conjugation with mechanical braking, particularly by actuation of Pivot Lever-Link (04) by simultaneous actuation of both the pedals, LH pedal (07) and RH pedal (06).
Linkages for actuation of braking system, as claimed in claim 1, wherein the brake-potentiometer (01) is mounted on a bracket (01a) and the Input is connected with actuating lever (02).
Linkages for actuation of braking system, as claimed in claim 1, wherein said mechanical linkage is characterized in structural and functional arrangements in Electric tractor, so that for making turn and in need of minimum turning radius while doing farming, said Electric tractor is capable of using independent brake and simultaneously its drive motor gets powered-up.
Linkages for actuation of braking system, as claimed in claim 1, wherein said mechanical linkage of brake pedals are characterized in making right (06) and left (07) brake pedals work independently without actuating brake-potentiometer (01) and maintaining the line-contact (11) with the Pivot Lever Link (04) by at least one of the pedal-pivot Lugs (08) and (09) therein.
Linkages for actuation of braking system, as claimed in claim 1, wherein the method of operation of said mechanical linkages is so provisioned that the brake-potentiometer (01) actuates only when both the brake pedals, (06) and (07) are pressed.

Linkages for actuation of braking system, as claimed in claim 1, wherein Actuating Mechanism is explained as under:
Figure no. 01 and 02 shows the brake subassembly with installation of brake-potentiometer. In figure 01, brake-potentiometer (01) is mounted on a bracket (01a) and the Input is connected with actuating lever (02). As already stated, motive of the design of this mechanism is to give the actuation to this lever (2) whenever both the Pedals (06) and (07) are actuated. Connecting clevis link (03) provides the actuation to the lever (02) when it is pushed by pivot lever-link (04). Said lever-link (04) is pivoted about a hinge pin (04a) and assembled on the Bracket Assembly (05). This pivot lever-link (04) is connected with a spring (10) which always tries to pull the lever-link (04). RH Pedal (06) and LH Pedal (07) are having LH pedal-pivot Lugs (08) and (09) respectively. LH pedal-pivot lug (08) and RH pedal-pivot lug (09) are having line contact (11) with lever-link (04) and always oppose said link (04) to be actuated until the pedals are pressed.
Linkages for actuation of braking system, as claimed in claim 1, wherein Left-Hand Side (LH) Brake Actuation is explained as under:
Figure no. 03 & 04 shows the individual actuation of both the pedals (06) and (07). In Figure no. 03, LH brake actuation is shown where LH pedal (07) is pressed. In this figure it can be easily understand that after the actuation of the LH pedal (07), LH pedal-pivot lug (09) is rotated by some angle and has left the line contact with the pivot lever-link (04), but said pivot lever-link (04) is not actuating. This is because RH pedal-pivot lug (08) remains in line contact (11) with the said pivot lever-link (04) and therefore not allowing the said pivot

lever-link (04) to move forward, thus restricting the actuation of link no (03) and (02). The same phenomenon happens in case of RH brake actuation.
Linkages for actuation of braking system, as claimed in claim 1, wherein Right-Hand Side (RH) Brake Actuation is explained as under:
In Figure no. 04, RH brake actuation is shown where RH pedal (06) is pressed. Again in this figure it can be easily understand that after the actuation of the RH pedal (06), RH pedal-pivot lug (08) is rotated by some angle and has left the line contact with the pivot lever-link (04) but said pivot link (04) is not actuating. This is because LH pedal-pivot lug (09)) remains in line contact (11) with the said pivot lever-link (04) and therefore not allowing the said pivot lever-link (04) to move forward, thus restricting the actuation of link no (03) and (02).
). Linkages for actuation of braking system, as claimed in claim 1, wherein Both Brake Pedals Actuation is explained as under:
Figure no. 05 and 06 shows the initial and actuated position of both the pedals (06) and (07). When both the pedals are on their initial position, both pedal-pivot lugs (08) and (09) remain in line contact (11) with the said pivot lever-link (04) and they do not allow the pivot lever-link (04) to move forward and restrict the said pivot lever-link (04) in its vertical position similarly when they restrict the motion in independent braking.
When both the Pedals, (06) and (07), are pressed together, both the pedal-pivot lugs, (08) and (09), are rotated by some angle as shown in the Figure no. 06 and try to leave the line contact with pivot lever-link (04)

simultaneously, as depicted by numeral 12 in Figure 6. Due to the pulling force of the spring (10), said pivot lever-link (04) actuates and is rotated by some angle as shown in the figure 6. When the pivot lever-link (04) actuates, it pushes the connecting link (03) linearly and ultimately gives the actuation to the Lever (02).