Claims:We claim:

1. A front wheel annular piston brake for tractors comprising of
Pedals
Two Master cylinders
a Reservoir
a Shuttle valve
an Intelligent Isolation Valve
a Proportionate valve
a Front Annular piston brake, and
a Rear Annular piston brake

characterized in that the two pairs of annular piston brake are provided inside a rear trumpet assembly and the inboard of a front wheel assembly.

2. A front wheel annular piston brake as claimed in Claim 1 wherein the shuttle valve provided in between the master cylinder assembly and the Isolation Valve circuit.

3. A front wheel annular piston brake as claimed in Claim 1 wherein the Intelligent Isolation Valve is provided between the Shuttle valve and the Front and Rear brake circuit.

4. A front wheel annular piston brake as claimed in Claim 1 and its working thereof wherein when the pedal is pressed, pressurized fluid from the Master cylinder passes through the Shuttle valve and the Isolation valve before reaching the Front and Rear Brake.

5. A front wheel annular piston brake as claimed in Claim 1 and its working thereof wherein when the pedal is pressed, all wheel brakes get energized and the brake is applied.

6. A front wheel annular piston brake as claimed in Claim 1 and its working thereof wherein at pedal latched condition, when pedal pressed both Master cylinders generate fluid pressure, the isolation valve being in on or off condition, passes fluids to both the Front and the Rear Circuit.

7. A front wheel annular piston brake as claimed in Claim 1 and its working thereof wherein at pedal unlatched condition, and when the isolation valve is on, when the left hand or right hand pedal is pressed, the left hand Master cylinder and the right hand master cylinder generates fluid pressure respectively, the front and the rear brake being applied accordingly.

8. A front wheel annular piston brake as claimed in Claim 1 and its working thereof wherein at pedal unlatched condition, when Isolation valve is off, when the left hand or right hand pedal is pressed, the left hand Master cylinder and the right hand master cylinder generates fluid pressure respectively, the Front circuit being isolated only rear brake will be applied.
, Description:TITLE
FRONT WHEEL ANNULAR PISTON BRAKE FOR TRACTORS

FIELD OF THE INVENTION

This invention relates to mechanical engineering, specifically automobile engineering and relates to an annular piston brake system. This invention more specifically relates to a front wheel annular piston brake for tractor application containing pedals, master cylinder, reservoir, shuttle valve, intelligent isolation valve, proportionate valve, front annular piston brake and rear annular piston brake.

BACKGROUND OF THE INVENTION

Agricultural tractors generally used in India ranges between 25~57 HP. Maximum Speed of the vehicle varies between 25~35 KPH. Mainly used for ploughing, tilling, disking, harrowing, planting, and similar tasks. These tractors are currently equipped with brakes in Rear Axle (Dry and Wet MPD brakes with mechanical actuation). The brakes are well proven for the above purposes. The maximum achievable deceleration with current brakes in high mue surfaces is 0.35 to 0.4 g.

The max speed and efficiency of the brakes (w.r.t deceleration) of the Vehicles other than farm tractors have increased considerably. When the farm tractor is used for haulage purposes, the max achievable deceleration with 2-wheel braking is not enough when compared to other road/ highway vehicles.

To understand the current brake performance (mechanically actuated Wet MPD brakes), Performance trials were carried out in current tractor with OIB brake system with existing mechanical actuation to ascertain the maximum achievable deceleration with 2-wheel braking system, which will be an input for design and development of 4-wheel braking system.

The usage of farm tractors for haulage purposes needs enhancement in brakes. To enhance road safety, Europe has revised the norms for tractors with speeds above 30kmph.

The minimum achievable deceleration should be 0.5g. The maximum achievable deceleration with current 2-wheel brake system in high mue surfaces is 0.35to 0.4 g. Just by increasing the braking force on rear axle will not achieve higher deceleration. It will only make the rear wheels to lock. To generate higher deceleration, the braking must be distributed to front axle as well.

Some of the prior art in this field reveal various improvements made over the years in the art, specifically in tractor brakes.

Indian Patent Application No: 2669/MUM/2014 discloses a hydraulic trailer brake system operated by the tractor's own hydraulic system and that, too, without a separate trailer brake control valve. The trailer brake system includes a hydraulic control valve equipped with an isolating valve for prioritizing of fluid flow either to trailer brake outlet or for implement operation. The hydraulic tractor brake system comprises: a hydraulic pump; a brake pedal; a draft lever; the tractor hydraulic system includes a hydraulic control valve, a combination of isolating valve and shut-off valve and a draft plunger; a plurality of linkages are provided for connecting and actuating the brake pedal, the draft plunger, the draft lever and the hydraulic control valve. A gap configured between the draft lever-hydraulic control valve linkage and the hydraulic control valve is adjusted by using draft lever for facilitating the synchronization of the tractor and trailer brake systems.

Indian Patent Application No: 201641037309 claims an all wheel braking system for a two wheel drive tractor to provide higher braking efficiency, comprises of plurality of brake assemblies (105, 106, 108,109), said plurality of brake assemblies (105, 106, 108, 109) actuates simultaneously and thus brake is applied on the dead axle (104) and the live axle (107). This system improves the braking functionality of the braking system by approximately 25~40%.

Indian Patent Application No: 5772/DELNP/2010 discloses a tractor steer-by-braking (SBF) pedal arrangement (10). The pedal arrangement (10) is characterized by having a central brake pedal (11) connected on one side to a right side pedal (12), and on the other side to a left side pedal (13). The central brake pedal (11) acts on a brake system (SBF) to produce the desired braking action. Each of the two side pedals (12, 13), when foot-operated by the driver, generate an activating signal to activate an electronic brake system, which only activates the brake required to steer-by-braking (SBF) in the desired (right or left) direction.

Indian Patent Application No: 1412/KOL/2006 claims an installation of braking device arrangement in the trailer Truck with a synchronization of Tractor brake. The new braking device comprising of installation of new compression with accessories in the tractor and a pneumatic brake attachment with a master cylinder with a provision of a brake fluid container and an additional air tank is provided with the tractor to cater air to air tank of the trailer truck via a flexible air pipe. The trailer equipped with a pneumatic braking device which is controlled by a hand lever by the driver via a control brake - valve of the tractor.

With the foregoing in mind, therefore it is the need of the hour is to develop a front wheel annular piston brake for tractors that offers huge cost benefits, less pedal effort, a compact mechanism, reduce service costs, offer better alignment of the brake housing, and provide a more efficient and speedy brake system for tractors.

The primary purpose of the present invention is to offer an alternate to the four wheel drive with automatic engagement in a tractor to meet European regulation requirement. By this way, huge cost benefit is accrued at customer end.

This invention eventually addresses the above and proves to be performance efficient, cost effective and eases the assembly. These and other objects of the invention will become more apparent in the course of the ensuing specification and claims when taken with the accompanying drawings.

Further it will be apparent to those skilled in the art that the objects of this invention have been achieved by providing a front wheel annular piston brake for tractors which is unique in nature unlike existing tractor braking systems as described in the above prior art. Various changes may be made in and without departing from the concept of the invention. Additional features of the invention will be described hereinafter that form the subject of the claims of the invention. Those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiment as a basis for designing and modifying other methods and structures for carrying out the same purpose of the present invention. Further, features of some stages disclosed in this application may be employed with features of other stages. Therefore, the scope of the invention is to be determined by the terminology of the following claims and the legal equivalents thereof.

OBJECTIVES OF THE INVENTION

This invention may be summarized, at least in part, with reference to its objects.

The foremost object of the present invention is to present a front wheel annular piston brake for tractors with huge cost benefits.

Another object of the present invention is to present a front wheel annular piston brake for tractors with Hydraulic brake actuation using Mineral oil system.

Another object of the present invention is to provide a front wheel annular piston brake for tractors with enhanced brake efficiency with a maximum deceleration of 0.57g - 35% reduction in stopping distance.

Another object of the present invention is to provide a front wheel annular piston brake for tractors with a compact mechanism mainly for the haulage purpose.

A further object of the present invention is to provide a front wheel annular piston brake for tractors offering better alignment of the brake housing where Braking is Progressive and Brake feel is consistent.

A further object of the present invention is to provide a front wheel annular piston brake for tractors that provides a more efficient and speedy four wheel braking with self adjusted brake system for tractors.

Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention.

SUMMARY OF THE INVENTION

The present invention embodies a front wheel annular piston brake for tractors.

The entire assembly comprises of the following parts:

1. Pedals
2. Master cylinder
3. Reservoir
4. Shuttle valve
5. Intelligent Isolation Valve
6. Proportionate valve
7. Front APB
8. Rear APB

DESCRIPTION OF THE DRAWINGS

The advantages and features of the present invention will be more readily apparent by persons skilled in the art when considered in reference to the following description and when taken in conjunction with the accompanying drawings listed below

Figure 1 is a detail view of the present invention brake system layout & description.

Figure 2 is a layout view of the present invention brake system with isolation valve function.

Figure 3 is a detail view illustrating the working of the present invention brake system pedal latched - isolation valve ON/ OFF condition.

Figure 4 is a cross sectional view illustrating the present invention brake system pedal unlatched - isolation valve ON / OFF condition.

DETAILED DESCRIPTION

The following description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of particular applications of the invention and their requirements. The present invention can be configured as follows:

The present invention is a front wheel annular piston brake for tractors with cost benefits, for lesser pedal effort and for more durability.

Construction

As shown in Figures 1 to 4, the present invention components are as follows:

According to a preferred embodiment of the present invention, as depicted in Figure 1, the entire assembly of the present invention comprises of the following parts:

1. Pedal
2. Master cylinder
3. Reservoir
4. Shuttle valve
5. Intelligent Isolation Valve
6. Proportionate valve
7. Front APB
8. Rear APB

Two Master cylinders (2) are provided in this system to create fluid pressure when pedal (1) is pressed. Two pairs of Annular piston brakes (7) (8) provided inside Rear Trumpet assembly and Inboard of front wheel assembly. A shuttle valve (4) provided in between MC assembly (2) and Isolation Valve circuit (5). An Intelligent Isolation Valve (5) is provided between Shuttle valve (4) and Front (7) and Rear (8) brake circuit. When pedal is pressed pressurized fluid from Master cylinder (2) pass through Shuttle valve (4) and Isolation valve (5) before reach Front and Rear Brake. When pedal (1) is pressed, all wheel brakes get energized and brake applied.

Pedal Latched - Isolation Valve ON/ OFF Condition

According to a preferred embodiment of the present invention, as depicted in Figure 3 at pedal (1) latched condition, when pedal (1) is pressed both Master cylinders (2) generate fluid pressure. At this condition a fool proof arrangement is designed in Isolation valve (5), such that invariable of the condition of the Isolation valve (5), whether ON or OFF condition, Isolation valve (5) will pass fluids to both Front (7) and Rear (8) Circuit.
This condition is applied when Tractor is on Road and tractor is used for haulage purposes.

Pedal Unlatched - Isolation Valve ON Condition:

According to a preferred embodiment of the present invention, as depicted in Figure 4, at pedal unlatched condition, and Isolation valve is ON, when LH or RH pedal pressed LH Master cylinder and RH master cylinder is generate fluid pressure respectively. So Front and rear brake will be applied accordingly.

Pedal Unlatched - Isolation Valve OFF Condition:

According to a preferred embodiment of the present invention, as depicted in Figure 4, at pedal unlatched condition, and Isolation valve is off, when LH or RH pedal pressed LH Master cylinder and RH master cylinder is generate fluid pressure respectively. Since Front circuit is isolated only rear brake will be applied. This condition is used for ploughing (Spin turn) purposes.

While there has been shown and described what is considered to be preferred embodiments of the invention, it will, of course, be understood that various modifications and changes in form or detail could readily be made without departing from the spirit of the invention. It is therefore intended that the invention be not limited to the exact forms described and illustrated, but should be constructed to cover all modifications that may fall within the scope of the appended claims.

It will be apparent to those skilled in the art that the objects of this invention have been achieved by providing the above invention. However various changes may be made in the structure of the invention without departing from the concept of the invention. Therefore, the scope of the invention is to be determined by the terminology of the following claims and the legal equivalents thereof.