Hood design-Week 2

HOOD DESIGN

Introduction

Hood or bonnet is the hinged cover over the engine of the motor vehicles that is used to access the engine compartment. Hood assembly consist of different parts that combine to be used in a vehicle. Various parts of the hood are:

1. Outer panel
2. Inner panel
3. Hinges
4. Latch & Striker Mechanism

In this report we will discuss the various design consideration used for designing various parts of the hood inner panel

Master Sketch

The master sketch utilised for designing the hood is shown below.

Embosses

Various embosses were made in the hood inner panel by keeping in mind the following design considerations

• Pedestrian safety during the frontal crash.
• To improve the strength and stiffness of the body.
• the embosses were designed in such a way that the distance between the hood inner panel and the outer panel was kept 5 mm from the points it had to be attached to each other.
• Hinge emboss was done keeping in mind the striker and hinge axis correlation.

Mastic Data

Mastic points are those points of the hood inner panel which are in contact with the hood outer panel with the help of sealants so as to minimise the effect of the vibrations produced by the engine.

 Following are the design considerations for the mastic points

• Diameter of the mastic points was taken as 8mm.
• Distance between the mastic point and hood outer panel is 5mm.
• The distance between two mastic points was kept in such a way so as to minimise the vibrational effects.

Hemming

Hemming is the process of joining the hood inner panel and the hood outer panel. Due to the styling finish of the vehicle both the panels cannot be joined using the welded joints so in order to avoid these joints hemming is used. Hemming for the hood was done with the help of the hemming data as shown.

In the corners a relief is to be provided during hemming and for this relief following data was used.

The figures below show the hemming and relief points in the designed model.

Assembly

• Hinges
• Latch & Striker 

OUTER PANNEL

INNER PANNEL