Claims:WE CLAIM:
1. A sealing structure for front axle (100) of a two wheel driven work vehicle, comprising of: a centre beam (101), a steering cylinder assembly (102), a plurality of hubs (103a,103b), pivot pin (104), and a plurality of spindle shafts (105a, 105b), Characterized in that
a) the front axle (100) is positioned above a Front Engine Support (FES) (106);
b) pivot shaft (107) provided with a rubber boot (108a, 108b) with gasket (109a, 109b), wherein the pivot pin (104) locks on the axle (100), a first bush (114) fitted on the FES (106) with direct greasing on said first bush(114) through a passage (117a);
c) a felt washer (115) positioned on the top of the spindle shaft (105a, 105b), and O-Ring with spacer (116) positioned at the bottom of the spindle shaft (105a, 105b); and
d) a mud block seal (118) positioned on the inner side of the hub (103a, 103b), a gasket (119) positioned on the outer side of the hub (103a, 103b), and dust shield (120) covering the said hub (103a, 103b) and having, hub cap (121) and bearings (122).

2. The sealing structure as claimed in claim 1, wherein due to higher distance from ground, the felt washer (115) sealing on the top of the spindle shaft (105a, 105b) provides an improved durability of said felt washer (115).

3. The sealing structure as claimed in claim 1, wherein the O-ring positioned at bottom of the spindle shaft (105a, 105b) prevents water entry against gravity and said spacer (116) reduces the contact area of sealing with external environment.

4. The sealing structure as claimed in claim 1, wherein the dust shield (120) prevents the direct contact of mud and no relative motion present between said hub cap (121) and said hub (103a, 103b) on the gasket (119) side.

5. The sealing structure as claimed in claim 1, wherein the dust shield (120) as an external element to the hub (103a, 103b) eliminates direct contact of sealing with external environments.

6. A sealing structure for front axle (100) of a two wheel driven work vehicle, comprising of: a centre beam (101), a steering cylinder assembly (102), a plurality of hubs (103a,103b), pivot pin (104), and a plurality of spindle shafts (105a, 105b), Characterized in that
a) the front axle (100) positioned above the Front Engine Support (FES) (106);
b) pivot shaft (106) provided with a V-Seal (111) with second O-Ring (110), wherein the pivot pin (104) is locked on the FES (106), a second bush (112) fitted on the axle (100), a channel (117b) for greasing said second bush (112) through the pivot pin (106);
c) a felt washer (115) positioned on the top of the spindle shaft (105a, 105b), and O-Rings with spacer (123) at the bottom of the spindle shaft (105a, 105b); and
d) a second lip oil seal (124) positioned on the inner side of the hub (103a, 103b) and gasket (119) on the outer side of the hub (103a, 103b) and dust shield (120) covering the said hub (103a, 103b) and having, hub cap (121) and bearings (122).

7. The sealing structure as claimed in claim 6, wherein due to higher distance from ground, the felt washer (115) sealing on the top of the spindle shaft (105a, 105b) provides an improved durability of said felt washer (115).

8. The sealing structure as claimed in claim 6, wherein the O-ring positioned at bottom of the spindle shaft (105a, 105b) prevents water entry against gravity and said spacer (116) reduces the contact area of sealing with external environment.

9. The sealing structure as claimed in claim 6, wherein the dust shield (121) prevents the direct contact of mud and no relative motion present between said hub cap (122) and said hub (103a,103b) on the gasket (120) side.

10. The sealing structure as claimed in claim 6, wherein the dust shield (121) as an external element to the hub (103a, 103b) eliminates direct contact of sealing with external environments.

Dated this 12th day of January 2021
, Description:FRONT AXLE SEALING STRUCTURE OF A TWO WHEEL DRIVEN WORK VEHICLE
FIELD OF INVENTION
The present invention relates to sealing structure in automotive vehicles. More particularly, the present invention relates to a sealing structure of a two wheel driven work vehicle, which creates higher ground clearance/distance and protects the bushes and bearing in a front axle of a work vehicle. The work vehicle is an agricultural vehicle such as tractor or farm vehicle.

BACKGROUND OF INVENTION
Generally, tractor is multi utility vehicle used along with attachments for different off road & agricultural application. Tractors can be of 2- wheel drive (2WD) or 4 –wheel drive(4WD). Tractor front axle is a mechanical part which houses bearing and bushes for its sub parts to have relative motion in order to maneuver the vehicle (i.e. Front hub free rotation, Spindle shaft, Pivot shaft rotation). 2WD tractors are economical and have better maneuverability when compared to 4WD tractors which has a higher traction but have higher repair costs. When tractor is used in application like puddling the bushes and bearings are exposed to mud and water which deteriorates its function and affects the usage. Hence sealing of bushes and bearing are vital need for a tractor front axle. Higher the distance from ground is less prone to water and dust entry, Therefore, low end sealing configuration is sufficient to protect the shafts, bearings & bushes.

Some of the prior arts are:
JPS543725A discloses a front axle structure for tractor where the height is adjusted by mounting a plurality through which a knuckle spindle is passed and mounted at both right and left ends of the front axle to move up and down the spindle. The said patent application includes a configuration where the tube spindle top includes a sealing member such as O-Ring with lid.
CN204420006U discloses a rim decelerating mechanism of front axle with limit and subtract housing and steering arm , includes a thrust bearing composite bush which is set in the periphery of a vertical shaft sleeve pipe, also the a stub axle bed is connected to the vertical shaft. The vertical shaft is provided with in a vertical shaft sleeve pipe. The vertical shaft sleeve and limit and subtract housing is provided with an anti-muddy water oil sealing with a composite bush where all the said features that has a complex mechanism and suits for 4-wheel drive model of tractors

CN203051772U discloses a front axle oil seal assembly with inner and outer oil seal which has an inner oil seal skeleton which is J-shaped and outer oil seal master lip is paid lip with outer seal and contacted with the axial component outer side of inner oil skeleton.

Conventionally the front axle configuration involves positioning of axle below FES or possess cassette type seal on the front hub thus rendering shafts, bearings & bushes more prone to dust entry. The present invention provides a unique configuration where the sealing elements at appropriate locations and the presence of the low end sealing configuration that is sufficient to protect the shafts, bearings & bushes.
Further, in the present invention with front axle above FES(i.e. Front Engine Support) configuration creates higher ground clearance/distance to the sealing zone than the existing prior arts which gives an advantage to go with low end sealing configurations and meeting the life requirement.
The present invention provides low cost sealing combination for front axle - 2WD models with use of rubber boot, gasket, V-seal(108) & O-rings(109) at appropriate location with basic principle of distancing (or) external feature between sealing element and external environment to meet its functional and life requirements for front hub, spindle shaft, pivot shaft bushes& bearings.
Conventionally the sealing configuration involves use of lip oil in all locations or and use of cassette type sealing elements which is costlier as well required special manufacturing process to meet its functional requirements.
Therefore there is need in art to provide a sealing configuration which is simple and efficient where it an address the technical problem involved in sealing configurations. This present invention is about the selection use of low end sealing elements at appropriate location with right design of its interface parts to meet the life requirement which is more technically advanced with existing prior arts.
The information disclosed in this background of disclosure section is only for enhancement of understanding of the general background of the invention and should not be taken as acknowledgement or any form of suggestion that this information forms the prior art already known to person skilled in the art.
OBJETIVE OF THE INVENTION
The main objective of the invention is to provide a sealing structure of a two wheel driven work vehicle, which creates higher ground clearance/distance and protects the bushes and bearing in a front axle of a two wheel drive work vehicle.
Yet another objective of the invention is to provide sealing elements at appropriate locations which would help in providing a cost effective solution to the front axle sealing configuration, especially in 2WD model of tractors

SUMMARY OF THE INVENTION

In an embodiment of the present subject matter relates to a sealing structure for front axle (100) of a two wheel driven work vehicle, comprising of: a centre beam (101), a steering cylinder assembly (102), a plurality of hubs (103a,103b), pivot pin (104), and a plurality of spindle shafts (105a, 105b), Characterized in that the front axle (100) is positioned above a Front Engine Support (FES) (106); pivot shaft (107) provided with a rubber boot (108a, 108b) with gasket (109a, 109b), wherein the pivot pin (104) locks on the axle (100), a first bush (114) fitted on the FES (106) with direct greasing on said first bush(114) through a passage (117a); a felt washer (115) positioned on the top of the spindle shaft (105a, 105b), and O-Ring with spacer (116) positioned at the bottom of the spindle shaft (105a, 105b); and a mud block seal (118) positioned on the inner side of the hub (103a, 103b), a gasket (119) positioned on the outer side of the hub (103a, 103b), and dust shield (120) covering the said hub (103a, 103b) and having, hub cap (121) and bearings (122).

In the preferred embodiment of the present invention, due to higher distance from ground, the felt washer (115) sealing on the top of the spindle shaft (105a, 105b) provides an improved durability of said felt washer (115).

In another embodiment of the present subject matter relates to a sealing structure for front axle (100) of a two wheel driven work vehicle, comprising of: a centre beam (101), a steering cylinder assembly (102), a plurality of hubs (103a,103b), pivot pin (104), and a plurality of spindle shafts (105a, 105b), Characterized in that the front axle (100) positioned above the Front Engine Support (FES) (106); pivot shaft (106) provided with a V-Seal (111) with second O-Ring (110), wherein the pivot pin (104) is locked on the FES (106), a second bush (112) fitted on the axle (100), a channel (117b) for greasing said second bush (112) through the pivot pin (106); a felt washer (115) positioned on the top of the spindle shaft (105a, 105b), and O-Rings with spacer(118) at the bottom of the spindle shaft (105a, 105b); and a second lip oil seal (119) positioned on the inner side of the hub (103a, 103b) and gasket (120) on the outer side of the hub (103a, 103b) and dust shield (121) covering the said hub (103a, 103b) and having, hub cap (122) and bearings (123).

In the preferred embodiment of the present invention, due to higher distance from ground as shown in Figure 8, the felt washer (115) sealing on the top of the spindle shaft (105a, 105b) provides an improved durability of said felt washer (115).

In the preferred embodiment of the present invention, the O-ring positioned at bottom of the spindle shaft (105a, 105b) prevents water entry against gravity and said spacer (116) reduces the contact area of sealing with external environment.

In the preferred embodiment of the present invention, the said dust shield (120) prevents the direct contact of mud and no relative motion present between said hub cap (121) and said hub (117) on the gasket (119) side.

In the preferred embodiment of the present invention, the dust shield (120) as an external element to the hub (117) eliminates direct contact of sealing with external environments.

BRIEF DESCRIPTION OF DRAWINGS
Figure 1: Illustrates sealing structure for front axle of a two wheel driven work vehicle according to the present invention.
Figure 2: Illustrates the sectional view of pivot shaft with the sealing structure having rubber boot with gasket for front axle of a two wheel driven work vehicle according to one embodiment of the present invention.
Figure 3: Illustrates the sectional enlarged view of spindle shaft with the sealing structure having felt washer in top and O-rings in bottom for front axle of a two wheel driven work vehicle according to one embodiment of the present invention.
Figure 4: the sectional view of hub with the sealing structure for front axle of a two wheel driven work vehicle according to one embodiment of the present invention.
Figure 5: Illustrates the sectional view of pivot shaft in the sealing structure with V-Seal with O-Ring for front axle of a two wheel driven work vehicle according to another embodiment of the present invention.
Figure 6: Illustrates the spacing / distancing of hub from ground in the front axle sealing structure of a two wheel driven work vehicle according to the prior art..
Figure 7: Illustrates the spacing / distancing of hub from ground in the front axle sealing structure of a two wheel driven work vehicle according to the present invention.
DETAILED DESCRIPTION FOR THE INVENTION
The present invention as embodied by a "Sealing structure for front axle of a two wheel driven work vehicle" succinctly fulfills the above-mentioned need[s] in the art. The present invention has objective[s] arising as a result of the above-mentioned need[s], said objective[s] being enumerated below. In as much as the objective[s] of the present invention are enumerated, it will be obvious to a person skilled in the art that, the enumerated objective[s] are not exhaustive of the present invention in its entirety, and are enclosed solely for the purpose of illustration. Further, the present invention encloses within its scope and purview, any structural alternative[s] and/or any functional equivalent[s] even though, such structural alternative[s] and/or any functional equivalent[s] are not mentioned explicitly herein or elsewhere, in the present disclosure. The present invention therefore encompasses also, any improvisation[s]/modification[s] applied to the structural alternative[s]/functional alternative[s] within its scope and purview. The present invention may be embodied in other specific form[s] without departing from the essential attributes thereof.
Throughout this specification, the use of the word "comprise" and variations such as "comprises" and "comprising" may imply the inclusion of an element or elements not specifically recited.
The present invention is thus directed to a sealing structure of a two wheel driven work vehicle, which creates higher ground clearance/distance and protects the bushes and bearing in a front axle of a work vehicle.

Referring to Figures 1 to 4, in an embodiment of the present invention, the sealing structure for front axle (100) of a two wheel driven work vehicle, comprising of: a centre beam (101), a steering cylinder assembly (102), a plurality of hubs (103a,103b), pivot pin (104), and a plurality of spindle shafts (105a, 105b), Characterized in that the front axle (100) is positioned above a Front Engine Support (FES) (106) as shown in Figure 1; pivot shaft (107) provided with a rubber boot (108a, 108b) with gasket (109a, 109b) as shown in as shown in Figure 2, wherein the pivot pin (104) locks on the axle (100), a first bush (114) fitted on the FES (106) with direct greasing on said first bush(114) through a passage (117a); a felt washer (115) positioned on the top of the spindle shaft (105a, 105b), and O-Ring with spacer (116) positioned at the bottom of the spindle shaft (105a, 105b) as shown in Figure 3; and a mud block seal (118) positioned on the inner side of the hub (103a, 103b), a gasket (119) positioned on the outer side of the hub (103a, 103b), and dust shield (120) covering the said hub (103a, 103b) and having, hub cap (121) and bearings (122) as shown in Figure 4.

In the preferred embodiment of the present invention, due to higher distance from ground, the felt washer (115) sealing on the top of the spindle shaft (105a, 105b) provides an improved durability of said felt washer (115).

In the preferred embodiment of the present invention, the O-ring positioned at bottom of the spindle shaft (105a, 105b) prevents water entry against gravity and said spacer (116) reduces the contact area of sealing with external environment.

In the preferred embodiment of the present invention, the said dust shield (120) as shown in Figure 4 prevents the direct contact of mud and no relative motion present between said hub cap (121) and said hub (103a, 103b) on the gasket (119) side.

In the preferred embodiment of the present invention, the dust shield (120) as an external element to the hub (103a, 103b) eliminates direct contact of sealing with external environments.

Referring to Figures 1 to 5, in an embodiment of the present invention, the sealing structure for front axle (100) of a two wheel driven work vehicle, comprising of: a centre beam (101), a steering cylinder assembly (102), a plurality of hubs (103a,103b), pivot pin (104), and a plurality of spindle shafts (105a, 105b), Characterized in that the front axle (100) positioned above the Front Engine Support (FES) (106) as shown in Figure 1; pivot shaft (106) provided with a V-Seal (111) with second O-Ring (110) as shown in Figure 5, wherein the pivot pin (104) is locked on the FES (106), a second bush (112) fitted on the axle (100), a channel (117b) for greasing said second bush (112) through the pivot pin (106); a felt washer (115) positioned on the top of the spindle shaft (105a, 105b), and O-Rings with spacer(123) at the bottom of the spindle shaft (105a, 105b) as shown in Figure 3; and a second lip oil seal (124) positioned on the inner side of the hub (103a, 103b) and gasket (119) on the outer side of the hub (103a, 103b) and dust shield (120) covering the said hub (103a, 103b) and having, hub cap (121) and bearings (122) as shown in Figure 4.

In the preferred embodiment of the present invention, due to higher distance from ground as shown in Figure 7, the felt washer (115) sealing on the top of the spindle shaft (105a, 105b) provides an improved durability of said felt washer (115).

In the preferred embodiment of the present invention, the O-ring positioned at bottom of the spindle shaft (105a, 105b) prevents water entry against gravity and said spacer (116) reduces the contact area of sealing with external environment.

In the preferred embodiment of the present invention, the dust shield (121) prevents the direct contact of mud and no relative motion present between said hub cap (122) and said hub (103a,103b) on the gasket (120) side.

In the preferred embodiment of the present invention, the dust shield (121) as an external element to the hub (103a, 103b) eliminates direct contact of sealing with external environments.

In the preferred embodiment of the present invention, the combination of sealing elements provides a low-cost sealing configuration.

In the preferred embodiment of the present invention, the sealing structure for front axle (100) creates higher ground clearance/distance and protects the bushes and bearing in said front axle of a two wheel drive work vehicle.
For illustration,
Example 1
In a specific example low cost sealing combination for Front axle - 2WD models with use of rubber boot (108a, 108b), gasket (109a, 109b), V-seal (111) & O-rings (110) at appropriate location with basic principle of distancing (or) external feature between sealing element and external environment allows to meet its functional and life requirements for the hub (103a, 103b), spindle shaft (105a, 105b), pivot shaft (106) bushes (112) & bearings (122). The front axle (100) is positioned above the front engine support (106). The sealing elements connected to pivot shaft (106) includes rubber boot (108a, 108b), gasket (109a, 109b), V-seal (111) & O-rings (110) by replacing lip oil in the conventional sealing structure. The said sealing structure is cheaper and and requires lighter tolerance control on assembly which reduces the over all product cost. This invention life is equivalent to existing configuration due to its location from ground is higher.
Example 2
In a specific example spindle shaft (105a, 105b) of the sealing structure of present invention provides an efficient sealing configuration where top of the spindle shaft (105a, 105b) is having felt washer (115) and bottom with O-rings with spacer (123) as shown in Figure 3, unlike the conventional sealing configurations where lip oil is used on both the sides. Due to higher distance from ground is greater than 250mm as shown in Figure 7, sealing on top with felt washer (115) life is better than a lip oil seal. Where else, Spacing/distancing (or) height from front hub to Pivot pin on existing prior arts is around 150 mm as shown in Figure 6. On bottom, the O-rings with spacer (123) is more sufficient as the water entry against gravity is not possible. Further, the said combination of sealing elements gives low cost sealing configuration.

Example 3
In a specific example, hub (103a, 103b) of the sealing structure of present invention comprising dust shield (120), mud block seal (118) / second lip oil seal (124) & gasket (119), wherein the mud block seal (118) is positioned on the inner side and gasket (119) on outer side. Further, dust shield (120) on the hub (103a, 103b) prevents the direct contact of mud, water which gives an advantage to go with mud block seal and give equivalent life to conventional cassette type seal.

It will be apparent to a person s killed in the art that the above description is for illustrative purposes only and should not be considered as limiting. Various modifications, additions, alterations, and improvements without deviating from the spirit and the scope of the invention may be made by a person skilled in the art.