Design and development of Automobile Back Door

DESIGN OF AUTOMOTIVE TAILGATE (BACK DOOR)

Objective :

To Design Car back door using Class 'A' surface by method of automotive sheet metal design .

Software Used : NX 11

Introduction :

A car backdoor is also called as tailgate. A tailgate, or sometimes the hatch, is a hinged board or door at the rear of a vehicle that can be moved up or down during loading and unloading. Also called a tailboard, it is commonly found in pickup trucks or hatchback vehicles.

In design of car back door outerpanel, innerpanel & necessary reinforcements also exists. Mostly in design considerations of sheetmetal aluminium & steel are used as per the budget standards of car.

With usage of Aluminium parts are easily casted with eliminating the reinforcements but the major drawback of the aluminium is high cost then compare to steel.

Steel Parts are stamped, we cannot vary the thickness of the part because of more number of parts are added,which could increase the weight of the part.So now a days most of the car manufacturers are trying to use Aluminium instead of Steel and they reduce the number of parts and weight of the car drastically.

Small Comparison between Steel & Aluminium

Steel Aluminium

Parts parts are stamped parts are casted

Reinforcement Necessary can be neglected

Thickness Constant can be varied

Components More less in number

Weight More Lighter

Cost Less in Cost As compared to Al More As compared to Steel

Components of back door :

Outer Upper Panel

Outer Lower Panel

Inner Panel

Gas Stay reinforcement

Wipermotor Reinforcement

Latch & Striker Mounting

Design consideration for a back door :

Rear Visibility

Boot Space and accessibility

Fit and Clearance

Support Structures like hinge and gas stays

Mounts for wiper motor, tail lamps, and other wiring loops.

Styling Class Surface :

Inner Panel :

Emboss :

Sheet metal embossing is a stamping process for producing raised or sunken design or relief in sheet metal. This process can be made by means of matched male and female roller dies or by passing sheet or a strip of metal between rolls of the desired pattern.

Embossing is done by pressing a sheet of par=per in to female die, That has a design etched into it. This is usually done with a male counter part underneath the paper so that the two and the design is transferred to the paper.

Force Distribution:

When the car hit at rear end, the force which acted should be react outside. The Y/V emboss which is helps to move the force to the outer end.

Hinge Reinforcement:

Hinges are the essential, that allows doors to pivot on one edged as open as they open and close. They are found on virtually all doors. It is a mechanical bearing that connects two solid objects, typically allowing only a limited angle of rotation between them.

Gas stay reinforcement:

It is used to lift up the Tail gate.

There are two types of Gas stay reinforcements,they are

• Manual System
• Power lift system

Manual system :

This mechanism is most used in India cars. It is operated man by his own.

Power Lift System :

It works on the basics of Sensor.

Latch and striker Reinforcement:

Latch placement :

Using the axis of the hinge, a circle is drawn at the middle of the back door and the latch is placed perpendicular to the circle.

Wiper motor reinforcement:

It is small electric motor which is mounted in the rear tail gate. It used to clean the rear wind sheid for clear visibility.

All Reinforcement Mountings :

Outer Upper Panel :

Outer Lower Panel :

Hemming :

Hemming is a forming operation in which the edges of the sheet are folded or folded over another part in order to achieve a tight fit. Normally hemming operations are used to connect parts together, to improve the appearance of a part and to reinforce part edges.

Hemming is used in assembly as a secondary operation after deep drawing, trimming and flanging operation to join two sheet metal parts(outer and inner ) together.

The accuracy of the hemming operation is very important since it affects the appearance of the surface and surface quality.

Corner Relief:

Relief helps to control sheet metal material behaviour and to prevent unwanted deformation during unbend operations. So here I gave two corner reliefs for back door.

BACK DOOR ASSEMBLY :

TOOLING DIRECTION :

The Tooling Direction is basically the direction that the mold pulls apart. The mold is built in two separate pieces, basically. You have a Cavity side and you have the Core side. The Core pulls apart from the Cavity and that's the Dyeline or the Tooling Direction.

DRAFT ANALYSIS :

CONCLUSION :

Design & Case study of Back Door BiW is done following all requirements and Engineering standards.