Field of the invention:
The invention relates to brake for tractors, particularly single housing-oil immersed brake for tractors.
Background:
Tractors have been in use for over 5 decades in India, as agriculture constitutes 70% of her primary occupation. Dry brakes with manual actuation were in use by the early tractor manufacturers. Indian farmers have been using the earliest of their kind for many years. The Indian market, which has always been extremely cost-sensitive, made the vehicle manufacturers think twice before incorporating advancement in technology, which in turn reflects on the cost. Keeping the Indian farmer in mind, the dry brakes were in use. Gradually, the advent of technology from the west combined with the improved exposure of the tractor manufacturers and there was a need for an improvement towards better tractors for varied usage. Also, frequent problems with dry brakes, low life and service difficulties necessitated the introduction of Oil immersed brakes as an effective replacement.
The dry brakes in use had a single-housing configuration. Brake assembly consists of actuator assembly along with two-friction disc on either side, assembled onto the axle flange of the vehicle. This assembly requires a slight shake or wobbles to ensure proper orientation of the friction disc onto the splined shaft.

The oil-immersed brake requires the assembly to be completely immersea in oil for proper functioning. The selection of friction and friction disc configuration is extremely vital for the oil-immersed brake. The co-efficient of friction and size of the friction disc demands more number of friction discs in case of oil immersed brake (OIB) unlike dry brakes. The friction discs also need to be separated by means of intermediate discs in case of OIB. The number of friction discs per brake is also dependent on the tractor weight - a higher weight requires more number of discs. In such cases, it is physically impossible to orient the multiple pairs of friction and intermediate discs for assembly as in the case of dry brakes. Split housing oil immersed brakes were necessary to facilitate assembly of friction and intermediate discs.
US 6,286,641 disclosed an oil brake that includes a piston that is mounted at the free end of a movable tubular rod which at its other end is integral with the stem of the brake, whereby the tubular rod moves in a hollow cylindrical body, thereby delimiting on both sides of the piston a first and a second working volume, whereby a central rod is arranged inside of the tubular rod and the tubular body contains at least one lateral opening that connects the second working volume to the first working volume via at least one central passage that is made between the tubular rod and the central rod and is formed by a relative difference in transverse dimensions between the central rod and the inside diameter of the tubular rod, whereby the opening or openings are formed on the tubular rod at a distance from the piston that is equal to at least half of the thickness of said piston, whereby the hollow cylindrical body is tightly closed with a plug and/or stem guide that is designed in such a way that, before the end of the expansion stroke, the openings that are formed on the tubular

rod are tightly sealed by the inside wall of the stem guide before all of the oil is evacuated from the second working volume toward the first working volume, forming a pocket of oil that is thick enough to constitute a hydraulic cushion for the piston.
Oil immersed brake in the prior art is a split housing oil-immersed brake consists of housing, an actuator assembly, intermediate discs, friction discs, and a cover. The housing is first mounted onto the vehicle, which is then used to locate and guide the friction and intermediate discs along with the actuator assembly. The cover is then used to seal the assembly with a gasket so as to prevent any leakage. Moreover the said split housing oil-immersed brake having many disadvantages such as number of parts are more, weight of the components are heavy and occupies more space.
So it is an object of the present invention is to provide a single-housing oil immersed brake to overcome the prior art problem. More particularly, this invention eventually reduces number of parts and weight of the components. The said oil immersed brake is highly economical and to be cost effective.
Summary of the invention:
One embodiment of the present invention is to provide a single housing oil immersed brake for tractors.
Another embodiment of the present invention is to provide an oil-immersed brake, which eventually reduces number of parts and weight of the components.
Yet another embodiment of the present invention is to provide a single-housing oil immersed brake ensures that the assembly is easier as compared to the spilt-housing type because of its lower weight.

Further embodiment of the present invention is to provide a single-housing oil immersed brake in which machining operations are eliminated.
Another embodiment of the present invention is to provide an oil-immersed brake, which can be upgraded the dry brake into wet brake system.
Further embodiment of the present invention is to provide externally mounted single-housing oil immersed brake with unique assembly feature of its kind.
Another embodiment of the present invention is to provide a single housing oil immersed brake, which is highly economical.
BRIEF DESCRIPTION OF THE DRAWINGS
Aspects of the present invention are pointed out with particularity in the appended claims. The present invention is illustrated by way of example in the accompanying drawings in which like references indicate similar elements. The following drawings disclose various embodiments of the present invention for purposes of illustration only and are not intended to limit the scope of the invention. For purposes of clarity, not every component may be labeled in every figure. In the figures:
Fig.1 illustrates the isometric view of the single housing oil immersed brake according
to the invention
Fig.2 illustrates a perspective view of housing
Fig. 3 illustrates a perspective view of actuator assembly
Fig. 4 illustrates a perspective view of intermediate disc
Fig. 5 illustrates a perspective view of friction disc
Fig. 6 illustrates a perspective view of assembly tool
Fig. 7 illustrates a perspective view of boot
Fig. 8 illustrates a sectional view of the oil-immersed brake when brake is off.
Fig. 9 illustrates a sectional view of the oil-immersed brake when brake is on.

Corresponding reference characters indicate corresponding parts throughout the several views of the invention. The exemplification set out herein illustrates one preferred embodiment of the invention, in one form, and such exemplification is not to be construed as limiting the scope of the invention in any manner. DETAILED DESCRIPTION OF INVENTION:
The following detailed description sets forth numerous specific details to provide a thorough understanding of the invention. However, those skilled in the art will appreciate that the invention may be practiced without these specific details. In other instances, well-known methods, procedures, components, protocols, algorithms, and circuits have not been described in detail so as not to obscure the invention.
Initially, about half of the housing is filled with oil. The intermediate discs, friction disc, actuator unit assembly are permanently immersed in oil. The oil circulation line is connected such that when the engine is on, there is continuous supply of oil through inlet to the brakes from the Hydraulic return line. This line ensures the continuous of oil flow. The excess oil (above center line of the housing) flows through spline shaft in to transmission housing. During operation, due to the rotation of friction disc, oil is splashed in side the brake housing.
According to the present invention, the single housing oil immersed brake includes a housing (1), Actuator assembly (2) with boot (6), plurality of intermediate discs (3), plurality of friction discs (4), which are mounted onto the axle flange (or) customer part (7) using the assembly tool (5). The intermediate disc (3) is designed to have 2 additional lugs with holes. The housing (1) has been engineered to incorporate the link operated mechanism. The friction disc (4) remains the same.

The assembly tool (5) is inserted onto the axle flange or customer part {{). i ne friction discs (4) are assembled with the help of the splined shaft wherein the intermediate discs (3) are assembled by passing them through the assembly tool (5) one after the other alternatively. The actuator assembly (2) along with the boot (6), the friction disc (4) and intermediate disc (3) are assembled finally along with the housing, which is used to cover the entire assembly and seal it.
Assembly tool (5) is inserted into the axle flange (7) at defined location as shown in Fig. 8. The intermediate disc (3) and friction disc (4) are assembled alternately, plurality of intermediate discs (3), plurality of friction discs (4), actuator assembly (2) and boot (6) are assembled sequentially to form sub assembly, the said sub assembly is mounted on to the main assembly of the axle flange (7) as shown in the The friction disc is guided by the spline shaft and intermediate disc by assembly tool wherein mounting bolts (8) are driven in the holes provided in housing (1) and the assembly tool is removed and holes are plugged.
Accordingly the single housing oil immersed brake for tractors comprising a housing (1) filled with a transmission oil and equipped with a actuator assembly (2) intended to receive an actuation force wherein plurality of intermediate discs (3) and friction discs (4) are assembled alternately onto the assembly tool (5) mounted on the axle flange (7) and the said friction disc (4) is guided by the spline shaft and the said intermediate disc (3) by assembly tool; actuator assembly (5) and boot (6) are assembled sequentially to form sub assembly, wherein the said sub assembly is mounted on to the main assembly of the axle flange (7); mounting bolts (8) are driven in the holes provided in housing (1) when a turning movement of actuator plates (21 and 22) is applied by direct pull at center of pivoted links and the said turning movement is converted into load parallel to the brake shaft by the steel balls rolling

up their inclined seats, thus producing the clamping load across the friction discs (4) wherein initial application of the clamping load cause both the actuator (21 and 22) to rotate in the same direction until the torque lug of one actuator abuts against the reaction face provided in the housing (1); the other actuator will then continue to rotate due to the initial clamping load applied, until a balanced condition is attained when the friction discs (4) slip.
In a preferred embodiment of the invention two assembly tools (5) are screwed into the axle flange (7) at defined location. The assembly tool has thread at one end and knurling at the other end. With the help of this assembly tool intermediate disc are located effectively.
Housing (1) has a hole for adaptor entry. Friction discs are inserted into the collapsible adaptor alternatively. Adopter is designed to receive the female spline shape of friction disc. Actuator assembly and intermediate disc are located in the housing lug. In one embodiment of the present invention, when the brake set is pushed towards the axle flange, collapsible adaptor hits the splines shaft. Hence adaptor moves in opposite direction, to the force applied for assembling the brake set. Adaptor is removed and bolts are tightened and the hole in the housing is plugged to prevent leakage.. The assembly tool is left permanently in the brake set. Hole in the housing is covered by the flange nut arrangement, which is screwed with the assembly tool.
In a preferred embodiment of the invention the intermediate disc is redesigned for compact assembly. Intermediate disc as internal lugs and hole to facilitate assembly.The assembly procedure and parts of the said brake assembly is described with respect to accompanying drawing, except the intermediate disc where the intermediate disc is redesigned.

In this oil immersed brake assembly dowels are optionally used to locate the intermediate disc perfectly. Intermediate disc with lug is designed to get located in the dowels. Dowels take the torque exerted on the intermediate disc. As shown, the spline shaft is used to guide the friction disc. During assembly, dowels are first doweled in the customer part. Friction and intermediate disc are assembled alternatively. Then sub assembly is bolted with the main assembly. Dowels in the axle flange to hold the intermediate disc positively.
The assembly tool is optionally left permanently in the brake set wherein one end of the assembly tool is screwed with the axle flange or customer part and other end is held with the boss in the housing.
A turning movement of actuator plates (21 and 22) is applied by direct pull using pull rod (20) at center of pivoted links. The turning moment is converted into load parallel to the brake shaft by the steel balls rolling up their inclined seats, as shown in figure - 9 thus producing the clamping load across the friction discs (4).
Initial application of the clamping load cause both the actuator (21 and 22) to rotate in the same direction as shown in figure- 8 until the torque lug (23) of one actuator abuts against the reaction face provided in the housing (1). The other actuator will then continue to rotate due to the initial clamping load applied, until a balanced condition is attained when the friction discs (4) slip.
ADVANTAGES OF THE INVENTION:
1. The single-housing oil immersed brake ensures that the assembly is easier as compared to the spilt-housing type because of its lower weight.
2. Reduced number of parts
3. Machining operations eliminated

4. Affordable cost
5. Greater opportunity to upgrade dry to wet brake system
The present invention is not to be limited in scope by the specific embodiments described herein. Indeed, various modifications of the present invention, in addition to those described herein, will be apparent to those of ordinary skill in the art from the foregoing description and accompanying drawings. Thus, such modifications are intended to fall within the scope of the following appended claims. Further, although the present invention has been described herein in the context of a particular implementation in a particular environment for a particular purpose, those of ordinary skill in the art will recognize that its usefulness is not limited thereto and that the present invention can be beneficially implemented in any number of environments for any number of purposes. Accordingly, the claims set forth below should be construed in view of the full breath and spirit of the present invention as disclosed herein.

We claim:
1. A single housing oil immersed brake for tractors comprising a housing (1) filled with a transmission oil and equipped with a actuator assembly (2) intended to receive an actuation force wherein plurality of intermediate discs (3) and friction discs (4) are assembled alternately onto the assembly tool (5) mounted on the axle flange (7) and the said friction disc (4) is guided by the spline shaft and the said intermediate disc (3) by assembly tool (5); actuator assembly (2) and boot (6) are assembled sequentially to form sub assembly, wherein the said sub assembly is mounted on to the main assembly of the axle flange (7); mounting bolts (8) are driven in the holes provided in housing (1) when a turning movement of actuator plates (21 and 22) . is applied by direct pull at center of pivoted links and the said turning movement is converted into load parallel to the brake shaft by the steel balls rolling up their inclined seats, thus producing the clamping load across the friction discs (4) wherein initial application of the clamping load cause both the actuator (21 and 22) to rotate in the same direction until the torque lug of one actuator abuts against the reaction face provided in the housing (1); the other actuator will then continue to rotate due to the initial clamping load applied, until a balanced condition is attained when the friction discs (4) slip.
2. A single housing oil immersed brake for tractors as claimed in claim ■ 1, wherein dowels are optionally used to locate the intermediate disc.

A single housing oil immersed brake for tractors as claimed in claim
1, wherein friction and intermediate disc are assembled alternatively
and then sub assembly is bolted with the main assembly.
A single housing oil immersed brake for tractors as claimed in claim
1, when the brake set is pushed towards the axle flange, collapsible
adaptor hits the splines shaft and the adaptor moves in opposite
direction, to the force applied for assembling the brake set wherein
adaptor is removed and bolts are tightened and the hole in the
housing is plugged to prevent leakage.
A single housing oil immersed brake for tractors as claimed in claim
1, wherein the assembly tool is left permanently in the said brake set.
A single housing oil immersed brake for tractors as claimed in claim
1, wherein intermediate disc as internal lugs and hole to facilitate
assembly..
A single housing oil immersed brake for tractors as claimed in claim
1, wherein the friction disc is guided by the spline shaft and
intermediate disc by assembly tool.
A single housing oil immersed brake for tractors as claimed in claim
1, wherein dowels in the axle flange to hold the intermediate disc
positively.

9. A single housing oil immersed brake for tractors as claimed in claim
1, the assembly tool has thread at one end and knurling at the other
end.
10. A single housing oil immersed brake for tractors is herein dercribed
and exemplified.