Hood design-Week 2

CAR HOOD DESIGN

AIM: To design the Hood or Bonet of the front driving car by using the master section and standard procedure which is used in the OEM Manufacturer's .

HOOD or BONET:

• Hood is the component which is placed over the engine compartment . The design of the hood is not only to enhance the look of the car , it also improves the aerodynamics of the car and the proper design which ensure the pedestrain safety .
• For Serviceability and maintanence of the car , hood is used to access the components like , engine , radiator , battery , etc. ,
• Over the period of time , designers has continously improving the hood design inorder to minimize the injuries of the pedestrain when he / she hits the hood while accident occurs . So it depends upon the material , design and structure of the hood .

Car Hood has the following components:

• Outer Panel
• Inner Panel
• Striker and Hinge asm Reinforcement
• Hood Support
• Mastic's

Outer Panel :

• Outer Panel is the most important part of the hood to makes the car in a very good aesthetic proportion . So that the outer panel is perfectly made insense to achieve the aesthatic requirement . So that , the sheet metal operation result which is visible on the outer panel or it reduces the aesthatic value means , those operations are strictly not to be followed to make the outer panel . That's why the hemming process is used to join the outer panel with the inner panel , instead of using welding methods .

Inner Panel:

• Inner Panel is the major part that ensures the rigidity of the hood and it is used to diverts the impact to outwards of the hood however possible when the collision occurs . It is can be achieved by the good inner panel design and the emboss direction in the inner panel .
• Lot of design changes and researches are done and being carried out in the inner panel only to achieve the pedestrain safety and the passenger safety to make the standards .

Reinforcement :

• The Striker and Hinges are attached at the lower side of the inner panel . It it can be done by directly then more stress can act at the particular area in the inner panel , it may cause deformation of the inner panel at that particular region . So that the reinforcement comes in and placed between the striker and the hood , hinge and the hood . It can able to reduce to deformation and strengthening the inner panel at that particular region .

Sheet Metal Operations :

1. Hemming :

• Hemming is used to fit the parts together . It can be done by the edges of one part is to be folded over the other part to fix within it . This operation is done by using the roller .
• Hoods , Doors , Boot lids of the automobile components are made by the hemming operation .
• There are two types of hemming process are there ,
• Conventional die hemming - In this method the hemming process is done by using the hemming die to fold the sheet metal edge by the entire length . entire lend
• Roll Hemming - In this method Rollers are used to done the process and at the same time two or more rollers are fold the sheet metal from the different location of the sheet metal edge to achieve the hemming which is close to accurate . Most of the automobile manufacturer are following the Roll hemming method due to its easier method when compare to the conventional die hemming .
• In Hood , the outer panel is subjected to the hemming operation which means that the outer panel edges is folded and roll it back to the underneath of the inner panel . The corner of the outer panel edge has to be trimmed , Because while hemming process the roller transfer pressure to the outer panel edge to fold it and roll it back , so that it may cause the problem that the sheet metal may break .

2 Deep Drawing :

• Deep Drawing is the sheet metal forming process . It is quite similar as punching process .
• Deep Drawing - The required sheet metal is to be clamped and the die with the required shape has to be kept below the sheet metal , then the sheet metal blank is drawn into that forming die by the pressure applied by the punch .

3. Embossing :

• Emboosing is kind of stamping process . It is the process of appliying the pressure to the flat sheet metal by the forming tool to create the projection on that sheet metal wherever required .
• In Hood design , the inner panel of the hood has more embosses to improving the strengthening of the panel . Based on the design structure , the embosses are created or we can say projected on the inner panel sheet metal .

4. Piercing :

• Piercing is the kind of shearing process in which the unwanted material with a particular shapes are removed from the sheet metal by using the blanking punch and dies .

I have attached a Zipped file containing Hood Assembly, Inner pannel, Outer pannel and the assembly components. Please click on Hood assembly CAD file.

this one

Thank You