FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See Section 10; rule 13)
TITLE OF THE INVENTION Hollow front axle beam & manufacturing process of the same
TATA MOTORS LIMITED, an Indian company
Having its registered office at Bombay House,
24 Homi Mody Street, Hutatma Chowk,
Mumbai 400 001 Maharashtra, India
INVENTORS
Mr. Deodatta Shende
Mr. Udayan Balvant Pathak
Mr. Niketan Kutkarni
Indian National
of TATA MOTORS LIMITED,
An Indian company having its registered office
at Bombay House, 24 Horni Mody Street, Hutatma Chowk,
Mumbai 400 001 Maharashtra, India
PREAMBLE TO THE DESCRIPTION
The following specification describes the invention and the manner in which it is to be
performed.

FIELD OF INVENTION:
The present invention relates to a hollow front axle beam more particularly a hollow beam through circular welding of tube to get desired fatigue life. The present disclosure also describes about the manufacturing process of the same.
BACKGROUND OF INVENTION:
Presently front axle beams are manufactured by using conventional die and press forging, machining and heat treatment. The vertical load and torsional load coming during the running of the vehicle is carried by the beam. Problems associated with the current designs are it is very heavy and bulky. The current design leads to usage of extra material and associated processing, machining and tooling cost is high, costly and energy intensive operations like through hardening, grinding required; thus making design unfriendly to environment.
OBJECT OF THIS INVENTION:
Object of this invention is to obviate the above mentioned drawbacks by
providing a hollow front axle beam through circular welding of tube to get desired
fatigue life.
Another object of the invention is to provide substitute for solid construction front
axle beam and offer environmental friendly design.
Yet another object of the invention is to enhance the strength of front axle beam
circular welding and the extra material processing for solid construction will
replaced by hollow construction.
SUMMARY OF INVENTION:
A hollow front axle beam comprising: a hollow tube with two goose neck structure joined at both ends of said hollow beam, a spring pad provided proximally to said goose neck on each side of hollow tube, said hollow tube is joined with said goose neck structure through circular welding of tube to get desired fatigue life.

The goose neck structure is manufactured by forging or machining or hydro-forming. The goose neck structure has the most uniform required engineering properties. The material used in goose neck is Medium Carbon steel. The material used for tube is low or medium Carbon steef.
The tube and goose neck is hardened thoroughly. The hardening is done by induction hardening or conventional hardening. The spring pad is joined by fastening or welding. The joining process of goose neck structure and hollow tube is a welding process like friction or TIG or MIG or submerged arc welding.
BRIEF DESCRIPTION OF THE DRAWINGS
The above brief description as well as further objects, features and advantages
of the present invention will be more fully appreciated by reference to the
following detailed description of presently preferred but nonetheless illustrative
embodiments in accord with the present invention when taken in conjunction with
the accompanying drawing wherein:
Figure 1 shows Front axle with goose neck and spring pad features
Figure 2 shows Isometric view of spring pad joined to front axle
DETAILED DESCRIPTION OF INVENTION:
A hollow front axle beam is substitute for solid construction front axle beam and offer environment friendly design. This gives similar performance during operation of the vehicle with reduced part weight also to ensure the static and dynamic strength. It also enhances the strength of front axle beam circular welding and the extra material processing for solid construction will replaced by hollow construction. This is also chip less environmental friendly process. The instant application does away with costly and energy intensive operations like

through hardening of bulk mass in conventional design by suitable and easier through hardening of lower mass for environmental sustainability and to ensure performance in motion and vibration characteristics.
The on going demand of saving fuel is forcing the automotive industry to reduce the weight of the components or parts and simultaneously improve the performance and reduce cost. This present disclosure incorporates the innovative combination of advanced welding and forming processes to get economical and wieght reduction proposal for front axle beam. Front axle beam is an important structural member of the vehicle. The beam carries the vertical load coming from the vehicle during the usage. Also multi axial load exerts on front axle beam.
The proposed feature in the front axle beam is a combination of joining processes between goose nake region and tube. Said joining process can be a welding process like friction or TIG or MIG or submerged arc welding.
This application incorporates the above mentioned findings and method of matching stiffness and fatigue requirements of the design along with the manufacturing techniques leading to the hollow construction of front axle through either of the following routes.
In one of the embodiment the goose neck (part 1) is manufactured by forging or machining or hydroforming. The goose neck formed by hydro forming has the most uniform required engineering properties. The goose neck is joined to hollow tube. Said joining is preferably by welding such as circular welding by TIG or MIG or C02 welding. The both side goose neck parts are identical to each other. The spring pad (part 3) is joined on the tube on desired location. The joining process can be fastening or welding through TIG/ MIG/ CO2 weld. Said spring pad is provided proximal to said goose neck on each side of hollow tube.

Materials used for tube low or medium Carbon steel and materials used in goose neck is Medium Carbon steel. Thorough hardening is done for tube and goose neck. The hardening process uses Induction hardening or Conventional hardening depending on the requirements. The material for spring pad is low carbon steel with / without heat treatment as per design requirement.
Advantages
1. Hollow construction with reduced part weight to give better fuel economy & hence environmental friendly design
2. Less material processing compared to solid construction. Chip less (Swarf) less environmental friendly design.
3. Reduction of costly and energy intensive operations like through hardening of bulk mass in conventional design by suitable and easier through hardening of lower mass for environmental sustainability.
The foregoing description is a specific embodiment of the present invention. It should be appreciated that this embodiment is described for purpose of illustration only, and that numerous alterations and modifications may be practiced by those skilled in the art without departing from the spirit and scope of the invention. It is intended that all such modifications and alterations be included insofar as they come within the scope of the invention as claimed or the equivalents thereof.

We Claim:
1. A hollow front axle beam comprising:
a hollow tube with two goose neck structure joined at both ends of said hollow
beam,
a spring pad provided proximally to said goose neck on each side of hollow tube,
said hollow tube is joined with said goose neck structure through circular welding
of tube to get desired fatigue life.
2. The hollow front axle beam as claimed in claim 1 wherein said goose neck structure is manufactured by forging or machining or hydro-forming.
3. The hollow front axle beam as claimed in claim 1 wherein said goose neck structure has the most uniform required engineering properties.
4. The hollow front axle beam as claimed in claim 1 wherein materials used in goose neck is Medium Carbon steel.
5. The hollow front axle beam as claimed in claim 1 wherein materials used for tube is low or medium Carbon steel.
6. The hoflow front axle beam as claimed in claim 1 wherein said tube and goose neck is hardened thoroughly.
7. The hollow front axle beam as claimed in claim 6 wherein said hardening is done by induction hardening or conventional hardening.
8. The hollow front axle beam as claimed in claim 1 wherein said spring pad is joined by fastening or welding.

9. The hollow front axle beam as claimed in claim 1 wherein said joining process
of goose neck structure and hollow tube is a welding process like friction or TIG
or MIG or submerged arc welding.
10. A hollow front axle beam and the manufacturing process of the same as
hereinabove described with reference to the accompanying drawings.