Design of backdoor

Design of back door using siemens NX Cad

Objective - To design and develop a back door by the given skin data in Siemens Nx Cad.

Introduction

Back Door

A back door is located at the rear side of the car which is also called as tailgate or rear door. Typically it is used to access when you want to store luguage. A car door is a type of door opening, typically hinged on its front edge, but sometimes attached by other mechanisms such as tracks, for entering and exiting a vehicle. Doors most often integrate side windows for visibility from inside the car and can be locked to secure the vehicle. Car doors may be manually operated or with power assist supplied by the vehicle. Powered doors or power doors may be found on minivans, luxury vehicles, or modified cars.

A back door is made of typically 1 inner panel and 2 or three outer panels. The materials used in a back door are of two types one is aluminium and other is steel. The low end cars usually use steel and high end use aluminium which is stamped using molds. These components are uniform in thickness and reinforcements are added locally to improve strength. The premium cars use aluminium doors and here reinforcements are not required hence keeping the weight even lower and they are die casted hence they can have variable thickness.

DESIGN CONSIDERATION FOR BACKDOOR INNER PANEL

1. Rear Visibility.

We have to design the back door by keeping in mind the nrear visibility of the driver when he is driving the car. Usually we give a glass sheet in the upper part of the back door parallel to the eye of drivers and passengers when they are seated on the seats.

2. Support structures like hinges and gas stays.

Hinges and gas stay have to be placed in the correct position so that there is nop jerks and problems while opening and closing the door

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

A mount for wiper motor should be provided to the back door to avoid problems in snow and rain. A cut out should be provided in the inner pannel to easily assemble the tail lamps to the back door. Wirring harness shouyld be provided accurately for a good flow of wires which attach to wiper moptor and tail lamp.

5. Boot space

The inner panel should be designed in such a way that there is no compromise in the boot space and it should be looked into that sufficient amount of space is available to load the luguages

6.Rear crash regulations and requirements.

The back door shouyld be designed in such a way that it adheres to crash regulations and requirements.

7.Sealing and its functions.

Adequate amount of sealing flange and at correct poosition should be provided so that there are no leaks during train and snow and the car is totally sealed

8.Joining techniques like hemming, spot welding etc.

TYPES OF DOOR OPENING:

1. Top mounted door

2. Side mounted door

3. Bottom Door

COMPONENTS OF BACKDOOR:

1. Inner panel

Inner pannel is usually of steel or aluminium depending upon the cost of the car. Emboss are provided because they act as reinforcements and distribute the load outside of the car. An extension is provided to the cut out so that it joins with the outer pannel. All the reinforcements like gas stay, stricker and hinge are provided to the inner panel. .

2. Outter panel upper

Outter pannel upper has an openiong for rear visibility with glass shield so that the driver is able to see at the rear side. It is usually the aesthetic part of the car and the skin data is designed by the styling team later trhe designing team makes a provision to join the outter panel and the inner pannel through hemming and mastic sealants. It also has cutouts for tail lamps

3. Outter panel lower

Same as outter panel upper. The l.iscence plate is usually attached on the outter panel lower

4. Hinge reinforcement

5. Gas stay reinforcement

6. Wiper motor reinforcement

7. Latch reinforcement

Draft analysis

Draft analysis performed on back door inner panel

Pictures of the full assembly of Back door

Conclusion

The designing of car back door is successfuly completed using siemens NX Cad with all the necessary parts and reinforcements.