Design of backdoor

OBJECTIVE:

1. Form the given styling surface, develop a backdoor using appropriate design methodologies.
2. The objective of this project is to design the back door of a car with an inner panel, outer panel and rewinforcement for the Hinge, Gas stay, Wiper motor and Latch by following the engineering standards.

INTRODUCTION:

The back door of the car is the rearmost part of the vehicle which gives access to the trunk space of the vehicle. The rear door also support the reinforcement and added weight of the Wiper motor, Gas stay, Tail lamp and Latch and striker.

The material used for door manufacturing depend on the budget and performance of the vehicle. Mostly aluminium and steel will be used.

PARTS AND REINFORCEMENT:

The backdoor consists of the following basic component:

1. Backdoor Upper Panel
2. Backdoor Outer Panel
3. Backdoor Inner Panel
4. Hinge Reinforcement
5. Gas-stay Reinforcement
6. Latch and Striker Reinforcement
7. Wiper Motor Reinforcement

DESIGN CONSIDERATION OF A BACKDOOR:

• Rear visibility criteria
• Functional requirement of hinge and gas stay
• Luggage volume
• Crash analysis

In this design outer panel is divided into two parts:

1. Outer Upper Panel
2. Outer Lower Panel

OUTER UPPER PANEL:

1. The outer upper panel extracted from a styling surface
2. The panel is altered for the required design with the surface tools
3. The thickness provided for the outer panel is 0.75mm.

OUTER LOWER PANEL:

1. The outer upper panel extracted from a styling surface
2. The panel is altered for the required design with the surface tools
3. The thickness provided for the outer panel is 0.75mm.

OUTER UPPER & LOWER PANEL:

TOOLING DIRECTION:

Before starting to design the inner panel of the backdoor the tooling direction for deep drawing purpose should be created.

INNER PANEL:

1. The inner panel extracted from a styling surface
2. The panel is altered for the required design with the surface tools
3. The thickness provided for the outer panel is 0.75mm.

MASTIC SEALANT:

The mastic sealant is used to fix the inner panel with the outer panel which increases the NVH factor and stiffness of the back door.

LATCH AND STRIKER EMBOSS:

The latch and striker emboss were designed by creating a trajectory that follows the opening and closing of the back door with repect to the hinge axis.

STRIKER POSITION:

The position of the hinge should be perpendicular to the latch when the latch and striker meets. The circle is drawn from the centre of the hinge axis to find the path of the striker and positioned perpendicular to the path.

HEMMING:

Hemming is metal working process in which a sheet metal edge is rolled over onto itself. Hemming is the process in which the edge is rolled flush to itself.

DESIGNING THE REINFORCEMENT:

The thickness provided for all reinforcement is 1mm

1. HINGE REINFORCEMENT
2. Gas stay REINFORCEMENT
3. Wiper motor REINFORCEMENT
4. Latch REINFORCEMENT

HINGE REINFORCEMENT:

Hinge enable the opening and closing of the backdoor. One end of the hinge is fixed on the backdoor and the other end on the roof on both sides.

GAS STAY REINFORCEMENT:

Gas stay is a device used for supporting the backdoor in its open position. Gas stay requires no manpower and is engaged into support position automatically as the back dooor opens. One end of the gas stay is fixed on the backdoor and the other end on the body side.

WIPER MOTOR REINFORCEMENT:

Wiper motor reinforcement is created to mount the wiper motor assembly.

LATCH AND STRIKER REINFORCEMENT:

The latch and striker forms the locking mechanism of the backdoor with the car. Due to regular opening, closing and over slamming of the backdoor, there is stress developed in the latch and striker area. To compensate for the same, reinforcement are added in this area.

DRAFT ANALYSIS:

VIEWS OF THE BACKDOOR:

FRONT VIEW:

SIDE VIEW:

TOP VIEW:

BOTTOM VIEW:

ISOMETRIC VIEW:

CONCLUSION:

Thus the backdoor of a car was designed following the engineering standards and also the deep drawing requirements were satisfied.