Design of backdoor

Final project:Design of Backdoor

Aim:To design backdoor outerpanel ,inner pannel,hemming flange ,sealing flange and do the draft analysis for the same

Tool used : Catia V5

Theory:

Backdoor exists in every car and is used to load and unload luggage in car.Backdoor is attached to the car body with the help of hinges.Gas stay mechanism keeps the door open while loading the car.Latch and striker mechanism keeps the door locked.Backdoor sealing flange prevents water from entering the car .

Backdoor is also known as trunk

Backdoor inner panels have embosses to direct the load in downwards to avoid stress concentration.

Types of backdoor :

Open compartments are those found in station wagons and SUVs, while closed compartments have a trunk lid and are typically found in saloon (sedan ) or coupe' bodies. Closed compartments are separated from the passenger compartment by rigid body elements or seats, and are generally trimmed in simple materials, whereas many station wagons are trimmed with better-looking materials as the space is an extension of the passenger compartment. In order to hide the compartment content of station wagons or hatchbacks from thieves or sunlight, a cover may be fitted. On hatchbacks this often has the form of a rigid parcel shelf or a flexible sheet with hooks on the corners, while station wagons and many SUVs have a roller blind in a removable cassette.

Methodology:

I designed the backdoor by creating separate parts of backdoor outerpanel ,inner panel,hemming flange and assembling them in the assembly workbench .

Outer panel.

I first repaired the given skin as it was erronous by using multisection,trim,extract,fillet etc commands .

Inner panel

In order to create inner panel I first created sealing flange using offset surface of outer panel .

Parallel curve,split,projection,multisection,spline commands are used to create the sealing flange .

The flange connecting the sealing flange and inner pannel is created using multisection ,sweep,split,multi section and spline.

The connecting flange is then trimmed by outerpanel

The remaining inner panel is created by using offset ,sweep,trim,split,multisection join and fillet

Finally the embosses for gas stay,hinge, latch ,wiper motor and embosses for damping load is created.

Symmetry command is used to mirror the inner panel

Hemming flange

Hemming flange is created by offseting the inner panel outer edge by 0.2mm and then creating a curvy surface between this inner panel outer edge.

This surface is created by using sweep,multisection and fillet command .Other commands like split,parallel curve, spline ,extract,multiple extract ,join are used

Draft Analysis

Tooling axis

Outer panel

Inner panel

Result:The design of backdoor was completed

Conclusion:Hemming flange and sealing flange can be improved.