DESC:FIELD OF THE INVENTION
[001] Present disclosure relates to an axle beam for a vehicle. More particularly, the present disclosure relates to an axle beam for a heavy vehicle.

BACKGROUND OF THE INVENTION
[002] Vehicles, such as heavy vehicles including but not limiting to trailer vehicles, comprise an axle as an essential component. The axle comprises an axle beam that supports weight of the vehicle, while also supporting wheels of the vehicle.
[003] Typically, the axle beam is subjected to bending loads due to weight and/or load on the vehicle. The axle beam is also subjected to shocks arising out of road surface irregularities during driving of the vehicle. Additionally, the axle beam is subjected to torque during braking of the vehicle. Also, turning of the vehicle results in a spring interface along the length of the axle beam and accordingly, unsymmetrical vertical loads act on the axle beam due to centrifugal action.
[004] Due to the aforementioned forces or load, an imperative limitation is the failure of the conventional axle beam. Failure can lead to bending of the axle beam leading to imbalanced wheels, cracking of the axle beam and eventually breaking of the axle beam when left unchecked leading to the vehicle stopping midway. Also, the failure can cause sudden detachment of the wheels from the axle beam, which can lead to safety hazards for the user as well as other vehicles in proximity.
[005] Typically, in order to accommodate load capacity of the vehicle, the axle beam is made of metal sheets having a thickness 14 mm. However, such axle beam is still incapable of accommodating the overall load capacity of the vehicle, which is undesirable. This scenario is more pronounced when the vehicle is overloaded, resulting in failure of the axle beam.
[006] In view of the above, there is a need for an axle beam to overcome one or more limitations stated above.

SUMMARY OF THE INVENTION
[007] In an aspect, the present invention relates to an axle beam for an axle of a vehicle. The axle beam includes a first elongated segment extending along a lateral axis of the vehicle. Further the axle beam includes a second elongated segment extending along the lateral axis of the vehicle. The second elongated segment is joined to the first elongated segment to form a hollow tubular member for supporting a spindle of the vehicle.
[008] In an embodiment, the first elongated segment and the second elongated segment are joined using Submerged Arc welding.
[009] In an embodiment, the first elongated segment and the second elongated segment are made of high-strength forged steel.
[010] In an embodiment, the first elongated segment and the second elongated segment are made of hot rolled ST52 steel.
[011] In an embodiment, the first elongated segment and the second elongated segment are made of a steel material having a thickness of 16 mm.
[012] In an embodiment, the hollow tubular member has a first end portion and a second end portion. Each of the first end portion and the second end portion are provided with a mounting profile. The mounting profile is adapted to support the spindle.
[013] In an embodiment, the mounting profile includes a first portion oriented along the lateral axis of the vehicle. The first portion is adapted to establish an interference fit with an inboard portion of the spindle. Further, the mounting profile includes a second portion adapted to engage with a rim surface of the inboard portion.
[014] In an embodiment, the first portion includes an inner surface. The inner surface is adapted to engage with an outer surface of the inboard portion of the spindle.
[015] In an embodiment, the first portion aligns and engages with a flange portion of the spindle.
[016] In an embodiment, the axle beam includes one or more support brackets. The one or more support brackets are adapted to support one or more brake shafts (S-Cam shafts) of a braking system provided in a wheel end assembly of the vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS
[017] Reference will be made to embodiments of the invention, examples of which may be illustrated in accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in context of these embodiments, it should be understood that it is not intended to limit the scope of the invention to these particular embodiments.
Figure 1 is a schematic view of an axle of a heavy vehicle comprising an axle beam, in accordance with an embodiment of the present invention.
Figure 2 is a sectional view of the axle beam, in accordance with an embodiment of the present invention.
Figure 3 is a sectional side view of the axle beam showing a welding seam, in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION
[018] The present disclosure provides an axle beam of a vehicle. More particularly, the present disclosure relates to the axle beam for a heavy vehicle. The axle beam in the present invention is formed from two halves made of hot rolled ST52 Steel. The two halves are welded using submerged arc welding. Thus, the axle beam of the present invention is characterized by uniform strength with high load bearing capacity. Therefore, the axle beam is capable of bearing heavy loads and shocks. In an embodiment, the vehicle can be a trailer, sub-trailer or any other multi-wheeled vehicle as per requirement.
[019] For the purpose of the present invention, a longitudinal axis of the vehicle refers to an axis along a length of the vehicle, a lateral axis of the vehicle refers to an axis along a width of the vehicle and a vertical axis of the vehicle refers to an axis along the height of the vehicle.
[020] Figure 1 is a schematic view of an axle 100 of a vehicle (not shown) in accordance with an exemplary embodiment of the present invention. The axle 100 comprises an axle beam 102 extending along a lateral axis (not shown) of the vehicle. The axle beam 102 is a hollow tube that acts as a base for holding or supporting components of the axle 100. In an embodiment, the axle 100 is of a heavy vehicle such as a trailer.
[021] Referring to Figure 2 in conjunction with Figure 1, the axle beam 102 is a hollow member having a first end portion 102a positioned towards a left side (not shown) of the vehicle, and a second end portion 102b positioned towards a right side (not shown) of the vehicle. The end portions 102a, 102b are adapted to engage with a spindle 104 of the vehicle. The spindle 104 in-turn engages with a wheel end assembly 106 (shown in Figure 1) of the vehicle. In an embodiment, the end portions 102a, 102b engage with a wheel rim 108 (shown in Figure 1) through the spindle 104, thereby ensuring engagement with the wheel end assembly 106. The wheel rim 108 accommodates a braking system (not shown) and tyres 110 (shown in the Figure 1) of the vehicle. In an embodiment, one or more support brackets 112 (shown in Figure 1) are provided on the axle beam 104. The support brackets 112 are adapted to support a brake shaft (S-Cam Shaft) 112 that extends up to the braking system provided in the wheel end assembly 106. In an embodiment, the one or more support brackets 112 support two brake shafts 112, wherein one brake shaft extends laterally towards the left side of the vehicle to engage with the braking system provided on the left side of the axle beam 102, while the other brake shaft extends laterally towards the right side of the vehicle to engage with the braking system provided on the right side of the axle beam 102.
[022] In an embodiment, each of the first end portion 102a and the second end portion 102b is provided with a mounting profile 122a, 122b. The mounting profile 122a, 122b is an annular profile provided to the axle beam 102, that is adapted to engage and support the spindle 104 (forged with 1045 steel) of the vehicle. In an embodiment, the first end portion 102a and the second end portion 102b are machined to form the mounting profile 122a, 122b. In an embodiment, the mounting profile 122a, 122b can be a stepped profile or an L-shaped profiled for accommodating the spindle 104.
[023] In an embodiment, the mounting profile 122a, 122b comprises a first portion 124a, 124b oriented along the lateral axis of the vehicle. The first portion 124a, 124b is adapted to establish an interference fit with an inboard portion 104a of the spindle 104. The term “inboard portion” corresponds to a portion of the spindle 104 that is accommodated within the axle beam 102. In the illustrated embodiment, an inner surface (not shown) of the first portion 124a, 124b is adapted to engage and establish an interference fit with an outer surface (not shown) of the inboard portion 104a of the spindle 104. The interference fit ensures a firm grip of the spindle 104 in the axle beam 102. Further, the mounting profile 122a, 122b comprises a second portion 126a, 126b adapted to engage with a rim surface 104c of the inboard portion 104a of the spindle 104. Thus, the second portion 126a, 126b acts as a stopper for the spindle 104. Furthermore, the first portion 124a, 124b comprises a rim 114a, 114b that engages with a flange portion 104b of the spindle 104. In the illustrated embodiment, the flange portion 104b is welded onto the rim 114a, 114b of the axle beam 102, upon interference fit between the left first portion 124a and the inboard portion 104a through conventional welding techniques known in the art, thereby locking the spindle 104 onto the axle beam 102. For clarity of references and identification, the first portion 124a, 124b and the second portion 126a, 126b are depicted towards upper portion/side of the axle beam 102.
[024] In an embodiment, the mounting profile 122a, 122b comprise a left mounting profile 122a provided to the first end portion 102a, and a right mounting profile 122b provided to the second end portion 102b. In an embodiment, the left mounting profile 122a and the right mounting profile 122b are symmetrical about a central axis (not shown) of the vehicle.
[025] The left mounting profile 122a is an elongated member that is adapted to engage with the spindle 104 mounted to the first end portion 102a i.e. the left side of the axle beam 102. The left mounting profile 122a comprises a left first portion 124a that extends along the lateral axis of the vehicle (or about a left-right direction of the vehicle). The left first portion 124a is adapted to establish an interference fit with the inboard portion 104a of the spindle 104 provided on the left side of the vehicle. In the illustrated embodiment, an inner surface (not shown) of the left first portion 124a engages and establish the interference fit with an outer surface (not shown) of the inboard portion 104a of the spindle 104. In an embodiment, the left first portion 124a engages with the inboard portion 104a through press-fitting technique.
[026] Further, the left mounting profile 122a comprises a left second portion 126a. The left second portion 126a is a member oriented laterally to the left first portion 124a and is adapted to engage with the rim surface 104c of the inboard portion 104a of the spindle 104. Thus, the left second portion 126a acts as a stopper for the spindle 104. In an embodiment, the left first portion 124a and the left second portion 126a forms an L-shaped profile or a stepped profile. In an embodiment, dimensions of the left first portion 124a and the left second portion 126a are considered corresponding to the engagement requirements with the spindle 104 (forged with 1045 steel).
[027] Additionally, the left first portion 124a comprises a left rim 114a that engages with a flange portion 104b of the spindle 104. In the illustrated embodiment, the flange portion 104b is welded onto the left rim 114a of the axle beam 102, upon interference fit between the left first portion 124a and the inboard portion 104a through conventional welding techniques known in the art, thereby locking the spindle 104 onto the axle beam 102.
[028] The right mounting profile 122b is an elongated member that is adapted to engage with the spindle 104 mounted to the second end portion 102b i.e. the right side of the axle beam 102. The right mounting profile 122b comprises a right first portion 124b that extends along the lateral axis of the vehicle (or about a left-right direction of the vehicle). The right first portion 124b is adapted to establish an interference fit with the inboard portion 104a of the spindle 104 provided on the right side of the vehicle. In the illustrated embodiment, an inner surface (not shown) of the right first portion 124b engages and establish the interference fit with an outer surface (not shown) of the inboard portion 104a of the spindle 104. In an embodiment, the right first portion 124b engages with the inboard portion 104a through press-fitting technique.
[029] Further, the right mounting profile 122b comprises a right second portion 126b. The left second portion 126a is a member oriented laterally to the left first portion 124a and is adapted to engage with the rim surface 104c of the inboard portion 104a of the spindle 104. Thus, the right second portion 126a acts as a stopper for the spindle 104. In an embodiment, the right first portion 124b and the right second portion 126b forms an L-shaped profile or a stepped profile. In an embodiment, dimensions of the right first portion 124b and the right second portion 126b are considered corresponding to the engagement requirements with the spindle 104.
[030] Additionally, the right first portion 124b comprises a right rim 114b that engages with the flange portion 104b of the spindle 104. In the illustrated embodiment, the flange portion 104b is welded onto the right rim 114b of the axle beam 102, upon interference fit between the right first portion 124b and the inboard portion 104a through conventional welding techniques known in the art, thereby locking the spindle 104 onto the axle beam 102.
[031] In an embodiment, each end portion 102a, 102b or the mounting profile 122a, 122b is machined through precision machining techniques known in the art for accommodating the spindle 104. In an embodiment, the rim 114a, 114b is provided with a profile that matches with the profile of the flange portion 104b of the spindle 104. In an embodiment, the rim 114a, 114b may be machined to form a fillet to match the profile of the flange portion 104b of the spindle 104.
[032] Referring to Figure 3 in conjunction with Figures 1 and 2, a sectional side view of the axle beam 102 is depicted. As shown, the axle beam 102 may be formed by joining a first elongated segment 116 and a second elongated segment 118. The elongated segments 116, 118 may be welded at their joining interfaces (referenced as ‘120’ in Figure 3) through a Submerged Arc Welding (SAW) technique. Joining the elongated segments 116, 118 through SAW provides consistent and uniform penetration on the weld and bonding, thereby ensuring uniform strength in the axle beam 102. Also, the slag generated during SAW provides an additional protective layer over the weld. The additional layer prevents exposure to the weld from atmospheric impurities, thereby ensuring longevity of the weld.
[033] In an embodiment, each of the elongated segments 116, 118 may be of a C-shaped cross-section or C-shaped profile. Accordingly, joining of the elongated segments 116, 118 having the C-shaped profile results in the axle beam 102 having a square shaped cross-section or square shaped profile. Alternatively, the profile of the elongated segments 116, 118 may be considered as per design feasibility and requirement in the axle beam 102. In an embodiment, the axle beam 102 may be formed by extrusion process.
[034] In an embodiment, each of the elongated segments 116, 118 are made of steel material. In another embodiment, each of the elongated segments 116, 118 are made of hot rolled ST-52 steel. Also, each of the elongated segments 116, 118 are provided with a thickness of 16 mm (as compared to 14 mm provided in conventional axle beams). Thus, the axle beam 102 formed through the elongated segments 116, 118 is characterized with a higher loading capacity and strength.
[035] Advantageously, the axle beam according to the present invention is formed by joining of two elongated segments through SAW, rendering consistent and uniform penetration on the weld and bonding, thereby ensuring uniform strength in the axle beam. Also, life of the axle beam is enhanced due to uniform and consistent welding of the elongated segments. Also, the elongated segments being made through forged ST52 steel provides additional strength to the axle beam. Also, the elongated segments are provided with a thickness of 16 mm sheet as compared to conventional 14 mm sheets, thereby providing additional strength to bear heavy loads and shocks. The improved load capacity of the axle beam also avoids any failure under irresponsible overloading. Additionally, machining of the ends of the axle beam ensures interference fit with the spindle, thereby enabling a firm grip of the spindle in the axle beam.
[036] While the present invention has been described with respect to certain embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the scope of the invention as defined in the following claims.

List of reference numerals
100 - Axle of a vehicle
102 - Axle beam
104 - Spindle
106 - Wheel end assembly
108 - Wheel rim
110 - Tyre
112 - Support brackets
114a, 114b – Rim
114a – Left rim
114b – Right rim
116 - First elongated segment
118 - Second elongated segment
120 - Weld
122a, 122b - Mounting profile
122a – Left mounting profile
122b - Right mounting profile
124a, 124b - First portion of the mounting profile
124a - Left first portion
124b - Right first portion
126a, 126b - Second portion of the mounting profile
126a - Left second portion
126b - Right second portion
,CLAIMS:WE CLAIM
1. An axle beam (102) for a vehicle, the axle beam (102) comprising:
a first elongated segment (116) extending along a lateral axis of the vehicle; and
a second elongated segment (118) extending along the lateral axis of the vehicle, the second elongated segment (118) joined to the first elongated segment (116) to form a hollow tubular member for supporting a spindle (104) of the vehicle.

2. The axle beam (102) as claimed in claim 1, wherein the first elongated segment (116) and the second elongated segment (118) being joined using Submerged Arc welding.

3. The axle beam (102) as claimed in claim 1, wherein the first elongated segment (116) and the second elongated segment (118) are made of high-strength forged steel.

4. The axle beam (102) as claimed in claim 3, wherein the first elongated segment (116) and the second elongated segment (118) are made of hot rolled ST52 steel.

5. The axle beam (102) as claimed in claim 1, wherein the first elongated segment (116) and the second elongated segment (118) being made of a steel material having a thickness of 16 mm.

6. The axle beam (102) as claimed in claim 1, wherein the hollow tubular member having a first end portion (102a) and a second end portion (102b), each of the first end portion (102a) and the second end portion (102b) provided with a mounting profile (122a, 122b), the mounting profile (122) being adapted to support the spindle (104).

7. The axle beam (102) as claimed in claim 6, wherein the mounting profile (122) comprises:
a first portion (124a, 124b) oriented along the lateral axis of the vehicle, the first portion (124a, 124b) being adapted to establish an interference fit with an inboard portion (104a) of the spindle (104); and
a second portion (126a, 126b) adapted to engage with a rim surface (104c) of the inboard portion (104a).

8. The axle beam (102) as claimed in claim 7, wherein the first portion (124a, 124b) comprises an inner surface, the inner surface adapted to engage with an outer surface of the inboard portion (104a) of the spindle (104).

9. The axle beam (102) as claimed in claim 7, wherein the first portion (122a) comprises a rim (114a, 114b), the rim (114a, 114b) adapted to engage with a flange portion (104b) of the spindle (104).

10. The axle beam (102) as claimed in claim 1, wherein the axle beam (102) comprises one or more support brackets (112), the one or more support brackets (112) being adapted to support one or more brake shafts (S-Cam shafts) of a braking system provided in a wheel end assembly (106) of the vehicle.

Dated this 8th day of February 2024.
RAMKRISHNA FORGINGS LIMITED
By their Agent & Attorney

(Adheesh Nargolkar)
of Khaitan & Co
Reg No IN/PA-1086