FIELD OF INVENTION
This invention relates to a novel welding sequence for Front Under-Body parts in automobile for enhanced body accuracy of the overall vehicle.
PRIOR ART
Conventional known welding sequence is as follows:-
1. The front cross member (Item-A), Brace lamp support R/L (Item F), Member lamp support R/L (item G), Member hood lock (Item H) & Brace Hood Lock (item J) are sub-assembled as Front End structure (Item-K in Fig. 4).
2. Separate sub-assemblies (Item -B) comprising of longitudinal members.
3. Separate sub-assembly (Item -D) consisting of dash comp.
4. Cowl box constitutes separate sub-assembly (Item-C).
5. Sub-assemblies as in Item-K, Item-B & Item-D are welded together in single welding jig.
6. Cowl box (Item- C) is welded to the above assembly.
OBJECTS OF THE INVENTION
The primary object of the present invention is to propose a novel welding sequence which involves significant space saving and easy material management in weld shop.
Another object of the present invention is to propose a novel welding sequence having superior body accuracy of the front under-body.
Further object of the present invention is to propose a novel welding sequence which is effective and efficient.
STATEMENT OF INVENTION
According to this invention, there is provided a novel welding sequence to form front under body structure of vehicle comprising of :- Preparation of the front cross member (Item -A), longitudinal members (Item -B), Cowl Box (Item -C) & Dash comp (Item -D) as sub-comp in different welding jigs, Preparation of a plurality of sub-assemblies (Item -E), Welding of Sub-assemblies as in Item-A, Item-B & Item E, and welding/assembling of brace lamp support (R/L) (item F), Member lamp support R/L (item G), Member hood lock (item H) and brace hood lock (item J).
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Further objects and advantages of this invention will be more apparent from the ensuing description when read in conjunction with the accompanying drawings and wherein:
Fig. 1, 2 and 3 shows:- Present invention. Fig. 4 shows:- Prior art.
DETAIL DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWINGS: -
The welding sequence of the present invention is as follows:-
• The front cross member (Item -A), longitudinal members (Item -B), Cowl Box (Item -C) & Dash comp (Item -D) are prepared as sub-comp in different welding jigs.
• A plurality of sub-assemblies (Item -E) comprising of cowl box (Item -C) and dash comp (Item- D) (Item-E).
• Sub-assemblies as in Item-A, Item-B 8B Item E are then welded together in single welding jig.
• In the same jig, brace lamp support (R/L) (item F), Member lamp support R/L (item G), Member hood lock (item H) and brace hood lock (item J) are welded/assembled.
• This completes the formation of front under body structure of vehicle.
Advantageous features of the invention over prior art:
• In the conventional welding sequence, the front end structure is
made separately as sub-assembly, before being welded together in
the front under-body. since the major components in the front end
are unsupported members hanging loosely, there is high possibility
of front end getting deformed during manufacturing and transfer to
the next state resulting in the overall deterioration of the body
accuracy in the front under-body area.
In the present welding sequence, the unsupported members of the conventional front end are welded in the last stage of the front under-body making. This ensures that, there is no deformation in this area ensuring superior body accuracy of the front under-body as a whole.
• In conventional welding assembly, first front end is welded on the front end welding jig. Thereafter, the front end and other front under body part are welded on the main jig. With new structure, critical parts for the appearance like member hood lock, member lamp support are welded on the main front under body jig. This reduces the number of the stages for the welding of the critical parts and hence, reduces the chances of transfer due to error of multiple jig usage.
• Since the critical members affecting the critical appearance parameter like gaps and level difference of the front facia assembly parts are welded on the single jig only. Therefore, adjustment as per production requirement can be done effectively. However, this is not the case in conventional welding process since the critical members undergo welding in more than on welding jig which leads to stacking up of errors/inaccuracy of the welding jig used for welding the parts.
• In conventional front end structure, space requirement the weld shop for the part storage is very high as the front end, which is open from type structure, requires more space for storage. With new welding sequence, this open frame type structure of front end is completely eliminated. Therefore, the child parts can be procured in smaller bins. This results in significant space saving and easy material management in weld shop.
• In case of conventional welding process, for multiple variants of front end structure, space requirement, in weld shop, for storing multiple variants is very high. Whereas in the present welding sequence, variation can be taken care by storage of multiple child parts of different variants in smaller bins on main line. This leads to significant space saving in weld shop.
It is to be noted that the present invention is susceptible to modifications, adaptations and changes by those skilled in the art. Such variant embodiments employing the concepts and features of this invention are intended to be within the scope of the present invention, which is further set forth under the following claims:-

WE CLAIM:
1. A novel welding sequence to form front under body structure of vehicle comprising of :-
• Preparation of the front cross member (Item -A), longitudinal members (Item -B), Cowl Box (Item -C) & Dash comp (Item -D) as sub-comp in different welding jigs,
• Preparation of a plurality of sub-assemblies (Item -E),
• Welding of Sub-assemblies as in Item-A, Item-B & Item E, and welding/assembling of brace lamp support (R/L) (item F), Member lamp support R/L (item G), Member hood lock (item H) and brace hood lock (item J).

2. A novel welding sequence as claimed in claim 1, wherein said sub-assemblies comprising of cowl box (Item-C) and dash comp (Item-D).
3. A novel welding sequence as claimed in claim 1 or 2, wherein said welding of sub-assemblies is carried out in single welding
jig-
4. A novel welding sequence to form front under body structure of
vehicle substantially as herein described with reference to the
accompanying drawings.