Hood design-Week 2

HOOD DESIGN

To create a detailed 3D design of HOOD ASSEMBLY using NX CAD

INTRODUCTION

To create a detail hood design using NX cad to get familier with different tools and methods of modelling.HOOD is the front most part and most important part when it comes to crash for safety of the passengers inside the vehicle.The hood is design in such a way that it absorb and divert the impact force away from the passenger in case of crash.

INNER PANNEL is the most important componet of the hood when it comes to give strength to the hood outer pannel it consist of all engineering features like emboss, reinforcement, hinge assembly , latch and stricker.

OUTER PANNEL is the aesthetic apperance of the hood. It is like the skin of the hood and inner pannel is the skeleton of the hood, combine they both provide the strength and good apperance of the car front most part.

REINFORCEMENT is in the inner pannel and provide extra strength and divert the imapct force in case of crash and provide the latch and hinge assembly fixatution place

DESIGN METHODOLOGY

DESCRIPTION

The hood is consist of major parts with the inner and outer pannel shown below

OUTER PANNEL

It is the aesthetic surface of the hood which provide the better looks and also provide the additional strength to the component. Image of the outer pannel of the hood is shown below:-

INNER PANNEL

It is the most important component of the hood assembly it consists of all the engineering features along with latch and stricker , hinge assemblies. Emboss and reinforcement are also created in the hood inner pannel.Emboss are for better strength of the hood and reinforecement are for the placement of the latch and hinge assembly. Image of hood inner pannel are shown below:-

HOOD INNER PANNEL

EMBOSS

The inner pannel has a raised surface for the strength and divert the force away from the passenger during the crash.

The emboss is designed in such a way they seems to be point away from the centre when viewed from the front of the vehicle

LATCH TRAJECTORY

Latch trajectory is the path for the stricker when the hood is open or closed.

It is being created by using the circle trajectory which is determine by the average height of the person in the contry for which the car is mad. The circle is drawn from the hinge axis.

MASTIC POINTS

Mastic points are the area where the mastics are applied to attach the hood inner pannel and outer pannel. As the spot welding is not sutable for that area because it will hinder the aesthetic appeal of the surface.

First image shows the mastic points where the mastic is going to apply

REINFORCEMENT

Area near the hinge and latch are the critical points and has more chance for the failure so the extra material for the thickeness is provided is known as reinforcement.Image below is shown for better understanding

For production of hood in the industry 2 process are used which are :-

• DEEP DRAWING
• HEMMING

1. DEEP DRAWING:-It is a process in which the sheet metal is formed in desired shape by using die and punch.The pressure is applied on the sheet metal with the help of punch and the die has the cavity which gives the shape to the sheet metal.

2. HEMMING:-It is the process in which the outer and inner pannel is joined together by folding the outer pannel curves and it is done by rolling ball method.The hem is created by using the flange at 90 degree and it is known as pre hemming.Finally the hem is created by pressing the sheet on the back of the inner pannel.

TREE STRUCTURE

DIFFERENT VIEWS

FRONT VIEW

RIGHT VIEW

BOTTOM VIEW

ISOMETRIC VIEW

CONCLUSION

Thus by following the above methods and tools the mention above HOOD ASSEMBLY is successfully created.