TECHNICAL FIELD
[001] The embodiments herein relate to a front axle drive mechanism for a vehicle.
BACKGROUND
[002] Vehicles such as tractors or other similar vehicles are primarily used in agricultural field operations. Four-wheel drive tractors are the emerging requirements in agriculture and industrial application for more traction generation at front wheel, reduction in slippage and more productivity. There are two types of four-wheel drive front axle, called Inline front axle and Offset front axle. Inline type four-wheel drive front axle is more popular for higher HP tractors where they have enough ground clearance due to bigger tire size. Offset type Four-wheel drive front axles are most popular for lower HP tractors where the need of ground clearance is more due to smaller tire sizes for agriculture applications. Conventional front axle final drive includes spiral bevel crown pinion & wheel, differential group and two stage reductions with straight bevel gear pairs which include intermediate bevel gear pairs and Final bevel gear pairs. The two-stage reductions with straight bevel gear pairs in the conventional final drive have some limitations of high power loss, assembly complications, higher development cost and higher noise and vibration.
[003] Therefore, there exists a need for a front axle drive mechanism for a vehicle, which obviates the aforementioned drawbacks.

OBJECTS
[004] The principal object of an embodiment herein is to provide a front axle drive mechanism for a vehicle, which has better efficiency.
[005] Another object of an embodiment herein is to provide a front axle drive mechanism for a vehicle, which allows easier preload and backlash checking.
[006] Another object of an embodiment herein is to provide a front axle drive mechanism for a vehicle, which has less noise and vibration.
[007] Another object of an embodiment herein is to provide a front axle drive mechanism for a vehicle, which is compact and has less weight.
[008] Another object of an embodiment herein is to provide a front axle drive mechanism for a vehicle, which has less power loss.
[009] Another object of an embodiment herein is to provide a front axle drive mechanism for a vehicle, which provides better wheel alignment angles.
[0010] These and other objects of the embodiments herein will be better appreciated and understood when considered in conjunction with following description and accompanying drawings. It should be understood, however, that the following descriptions, while indicating embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.

BRIEF DESCRIPTION OF DRAWINGS
[0011] The embodiments of the invention are illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0012] Fig. 1 depicts a cross-sectional view of a front axle drive mechanism for a vehicle, according to an embodiment as disclosed herein; and
[0013] Fig. 2 depicts an exploded view of a first double cardan shaft assembly, according to the embodiment as disclosed herein.
DETAILED DESCRIPTION
[0014] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.

[0015] The embodiments herein achieve a front axle drive mechanism for a vehicle, which has better efficiency. Further embodiments herein relate tofront axle drive mechanism for a vehicle, which is compact and has less weight. Referring now to the drawings Figs 1 through 2, where similar reference characters denote corresponding features consistently throughout the figures, there are shown embodiments.
[0016] Fig. 1 depicts a cross-sectional view of a front axle drive mechanism (100) for a vehicle, according to an embodiment as disclosed herein. In an embodiment, the front axle drive mechanism (100) includes a first double cardan shaft assembly (102), a first drive gear (104), a first output shaft (106), a second double cardan shaft assembly (108), a second drive gear (110), a second output shaft (112), a left side kingpin assembly (100LK), a right side kingpin assembly (100RK), a differential assembly (100D), a left side wheel spindle (100LW), a right side wheel spindle (100RW), a left side axle beam housing (100LH), a right side axle beam housing (100RH), a left side swivel housing (100LS), a right side swivel housing (100RS), a left side end cover (100LE), a right side end cover (100RE), a first sealing element (100FS), a second sealing element (100SS), a third sealing element (100RX), a fourth sealing element (100RY), a first slinger (100LG) and a second slinger (100RG).
[0017] Fig. 2 depicts an exploded view of a first double cardan shaft assembly (102), according to the embodiment as disclosed herein. The first double cardan shaft assembly (102) is adapted to be coupled between the first drive gear (104) and the differential gear assembly (100D). In an embodiment,

the first double cardan shaft assembly (102) includes axle shaft (102A), a yoke shaft (102B) and a yoke assembly (104C). The axle shaft (102A) is adapted to be rotatably connected to the differential gear assembly (100D). In an embodiment, the yoke shaft (102B) defines a pinion gear (102P) adapted to be rotatably connected to the first drive gear (104). For the purpose of this description and ease of understanding, the pinion gear (102P) is at least a helical pinion gear. It is also within the scope of the embodiment herein to provide the pinion gear (102P) in form of any other gears without otherwise deterring the intended function of the pinion gear (102P) as can be deduced from the description and corresponding
1 drawings. A longitudinal axis of the yoke shaft (102B) is provided at a predefined angle with respect to a longitudinal axis of the axle shaft (102A) of the first double cardan shaft assembly (102). In an embodiment, the yoke assembly (102C) comprises a center yoke (102Y), a first spider (102S1) and a second spider (102S2). The first spider (102S1) is adapted to couple the axle shaft (102A) with the center yoke (102Y). The second spider (102S2) is adapted to couple the yoke shaft (102B) with the center yoke (102Y). The first double cardan shaft assembly (102) is driven by the differential gear assembly (100D), and is adapted to drive the first drive gear (104) which in turn drives the left side wheel spindle (100LW). [0018] The first drive gear (104) is adapted to be mounted onto the first
1 output shaft (106). For the purpose of this description and ease of understanding, the first drive gear (104) is at least a helical drive gear. It is also within the scope of the embodiment herein to provide the first drive gear (104) in form of any other gears without otherwise deterring the intended function of the first drive gear

'104) as can be deduced from the description and corresponding drawings. The first output shaft (106) is adapted to mount the left side wheel spindle (100LW).
[0019] The second double cardan shaft assembly (108) is adapted to be ;oupled between the second drive gear (110) and the differential gear assembly '100D). The second double cardan shaft assembly (108) is opposite to the first double cardan shaft assembly (102). The second double cardan shaft assembly '108) includes axle shaft (108A), a yoke shaft (108B) and a yoke assembly '108C). The axle shaft (108A) is adapted to be rotatably connected to the differential gear assembly (100D). In an embodiment, the yoke shaft (108B) defines a pinion gear (108P) adapted to be rotatably connected with the second drive gear (110). For the purpose of this description and ease of understanding, :he pinion gear (108P) is at least a helical pinion gear. It is also within the scope 3f the embodiment herein to provide the pinion gear (108P) in form of any other gears without otherwise deterring the intended function of the pinion gear (108P) is can be deduced from the description and corresponding drawings. A ongitudinal axis of the yoke shaft (108B) is provided at a predefined angle with "espect to a longitudinal axis of the axle shaft (108A) of the second double cardan shaft assembly (108). In an embodiment, the yoke assembly (108C) includes a ;enter yoke (108Y), a first spider (108S1) and a second spider (108S2). The first spider (108S1) adapted to couple the axle shaft (108A) with the center yoke ;i08Y). The second spider (108S2) adapted to couple the yoke shaft (108B) with :he center yoke (108Y). The second double cardan shaft assembly (108) is driven
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by the differential gear assembly (100D), and is adapted to drive the second drive gear (110) which in turn drives the right side wheel spindle (100RW).
[0020] The second output shaft (112) is adapted to mount the right side wheel spindle (100RW). The second drive gear (110) is adapted to be mounted onto the second output shaft (112). For the purpose of this description and ease of understanding, the second drive gear (110) is at least a helical drive gear. It is also within the scope of the embodiment herein to provide the second drive gear (110) in form of any other gears without otherwise deterring the intended function of the second drive gear (110) as can be deduced from the description and corresponding drawings.
[0021] The left side kingpin assembly (100LK) comprises a left side kingpin shaft (100LA) and at least one bearing (100LB). The kingpin shaft (100LA) is operatively connected to a steering system (not shown) of the vehicle. The kingpin shaft (100LA) is connected to the left side axle beam housing (100LH). The kingpin shaft (100LA) is coupled to the left side swivel housing (100LS) through the bearing (100LB). A longitudinal axis of the kingpin shaft (100LA) is provided at a predefined angle with respect to the longitudinal axis of the axle shaft (102A) of the first double cardan shaft assembly (102). The longitudinal axis of the kingpin shaft (100LA) is provided at a predefined angle with respect to a vertical axis of the center yoke (102Y) of the yoke assembly (102C).
[0022] The left side swivel housing (100LS) is adapted to be coupled to the left side kingpin shaft (100LA) through the bearing (100LB). The left side
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swivel housing (100LS) is adapted to move the left side wheel spindle (100LW) through the left side end cover (100LE) with respect to the left side kingpin assembly (100LK) during operation of the steering system of the vehicle.
[0023] The left side end cover (100LE) is adapted to cover the first drive gear (104) and a portion of the first double cardan shaft assembly (102). The left side end cover (100LE) is adapted to be coupled with the left side swivel housing (100LS) and the left side wheel spindle (100LW).
[0024] The right side kingpin assembly (100RK) comprises a right side kingpin shaft (100RA) and at least one bearing (100RB). The kingpin shaft (100RA) is operatively connected to the steering system (not shown) of the vehicle. The kingpin shaft (100RA) is connected to the right side axle beam housing (100RH). The kingpin shaft (100RA) is coupled to the right side swivel housing (100RS) through the bearing (100RB). A longitudinal axis of the kingpin shaft (100RA) is provided at a predefined angle with respect to the longitudinal axis of the axle shaft (108A) of the second double cardan shaft assembly (108).The longitudinal axis of the kingpin shaft (100RA) is provided at a predefined angle with respect to a longitudinal axis of the center yoke (108Y) of the yoke assembly (108C).
[0025] The right side swivel housing (100RS) is adapted to be coupled to the right side kingpin shaft (100RA) through the bearing (100RB). The right side swivel housing (100RS) is adapted to move the right side wheel spindle (100RW) through theright side end cover (100RE) with respect to the right side kingpin assembly (100RK) during operation of the steering system of the vehicle.
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[0026] The right side end cover (100RE) is adapted to be coupled with the right side swivel housing (100RS) and the right side wheel spindle (100RW). The right side end cover (100RE) is adapted to cover the second drive gear (110) and a portion of the second double cardan shaft assembly (108). The right side end cover (100RE) is opposite to the left side end cover (100LE).
[0027] The left side axle beam housing (100LH) is adapted to house a portion of thefirst double cardan shaft assembly (102). The right side axle beam housing (100RH) is adapted to house a portion of thesecond double cardan shaft assembly (108). The right side axle beam housing (100RH) is opposite to the left side axle beam housing (100LH). The first sealing element (100FS) is provided between the left side axle beam housing (100LH) and the axle shaft (102A) of the first double cardan shaft assembly (102). The first sealing element (100FS) is adapted to restrict flow of fluid from a chamber (100CA) of the left side axle beam housing (100LH). The second sealing element (100SS) is provided between the left side swivel housing (100LS) and the yoke shaft (102B) of the first double cardan shaft assembly (102). The second sealing element (100SS) is adapted to restrict the flow of fluid from a chamber (100CB) defined between the left side swivel housing (100LS) and the left side axle beam housing (100LH). The second sealing element (100SS) is at least a cassette seal. The third sealing element (100RX) is provided between the right side axle beam housing (100RH) and the axle shaft (108A) of the second double cardan shaft assembly (108). The third sealing element (100RX) is used to restrict the flow of fluid from a chamber (100CC) of the right side axle beam housing (100RH). The fourth sealing

element (100RY) is provided between the right side swivel housing (100RS) and the right side axle beam housing (100RH). The fourth sealing element (100RY) is used to restrict the flow of fluid from a chamber (100CD) defined between the right side swivel housing (100RS) and the right side axle beam housing (100RH). The fourth sealing element (100RY) is at least a cassette seal. The first slinger (100LG) is adapted to restrict accumulation of dust, mud and other foreign particles onto the first sealing element (100FS). The second slinger (100RG) is adapted to restrict accumulation of dust, mud and other foreign particles onto the third sealing element (100RX).
[0028] Therefore, a front axle drive mechanism (100) for a vehicle, which has better efficiency, is provided.
[0029] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

We claim:
1. A front axle drive mechanism (100) for a vehicle, said mechanism (100)
comprising:
a first output shaft (106) adapted to mount a left side wheel spindle (100LW);
a first drive gear (104) adapted to be mounted onto said first output shaft (106);
a first double cardan shaft assembly(102) adapted to be coupled between said first drive gear (104) and a differential gear assembly (100D);
a second output shaft (112) adapted to mount a rightside wheel spindle (100RW);
a second drive gear (110) adapted to be mounted onto said second output shaft (112);
a second double cardan shaft assembly (108) adapted to be coupled between said second drive gear (110) and said differential gear assembly (100D), wherein
said first double cardan shaft assembly (102) is driven by said differential gear assembly (100D) and said first double cardan shaft assembly (102) is adapted to drive said first drive gear (104) which in turn drives said left side wheel spindle (100LW); and
said second double cardan shaft assembly (108) is driven by said differential gear assembly (100D) and said second double cardan shaft assembly

(108) is adapted to drive said second drive gear (110) which in turn drives said right side wheel spindle (100RW).
2. The mechanism (100) as claimed in claim 1, wherein said first double cardan
shaft assembly (102) comprises,
an axle shaft (102A) adapted to be rotatably connected to said differential gear assembly (100D);
a yoke shaft (102B) defining a pinion gear (102P) adapted to be rotatably connected to said first drive gear (104); and a yoke assembly (102C) comprising, a center yoke (102Y);
a first spider (102S1) adapted to couple said axle shaft (102A) with said center yoke (102Y); and
a second spider (102S2) adapted to couple said yoke shaft (102B) with said center yoke (102Y).
3. The mechanism (100) as claimed in claim 2, wherein said pinion gear (102P) is
at least a helical pinion gear; and
said first drive gear (104) is at least a helical drive gear.
4. The mechanism (100) as claimed in claim 1, wherein said second double cardan
shaft assembly (108) comprises,
an axle shaft (108A) adapted to be rotatably connected to said differential gear assembly (100D);

a yoke shaft (108B) defining a pinion gear (108P) adapted to be rotatably connected to said second drive gear (110); and a yoke assembly (108C) comprising, a center yoke (108Y);
a first spider (108S1) adapted to couple said axle shaft (108A) with said center yoke (108Y); and
a second spider (108S2) adapted to couple said yoke shaft (108B) with said center yoke (108Y).
5. The mechanism (100) as claimed in claim 4, wherein said pinion gear (108P) is
at least a helical pinion gear; and
said second drive gear (110) is at least a helical drive gear.
6. The front axle drive mechanism (100) as claimed in claim 1 comprises,
a left side kingpin assembly (100LK) comprising a left side kingpin shaft(lOOLA) and a bearing (100LB);
a left side swivel housing (100LS) adapted to be coupled to said left side kingpin shaft (100LA) through said bearing (100LB); and
a left side end cover (100LE) adapted to be coupled with said left side swivel housing (100LS) and said left side wheel spindle (100LW), wherein
said left side swivel housing (100LS) is adapted to move said left side wheel spindle (100LW) through said left side end cover (100LE) with respect to

said left side kingpin assembly (100LK) during operation of a steering system of
the vehicle.
7. The front axle drive mechanism (100) as claimed in claim 1 comprises,
a right side kingpin assembly (100RK) comprising a right side kingpin shaft (100RA) and a bearing (100RB);
a right side swivel housing (100RS) adapted to be coupled to said right side kingpin shaft (100RA) through said bearing (100RB); and
a right side end cover (100RE) adapted to be coupled with said right side swivel housing (100RS) and said right side wheel spindle (100RW), wherein
said right side swivel housing (100RS) is adapted to move said right side wheel spindle (100RW) through said right side end cover (100RE) with respect to said right side kingpin assembly (100RK) during operation of a steering system of the vehicle.