Hood design-Week 2

HOOD DESIGN

It is the covering for engine in front engine vehicles, which protects the engine from sunlight and dust.

It functions are

• Helps in aerodynamical flow.
• Protects the passenger and pedestrian.
• Reduces the air resistance.

COMPONENTS OF HOOD

SUPPORT ROD

The support rod is placed inside the engine compartment, to keep the hood open and its one end is attached on hood and other end other on engine side.it is done manually.

GAS STAY

Use compressed gas to open bonnet automatically.mainly used in high performance cars.

LATCH STRIKER

It is used for locking mechanism of hinge and engine side.

HINGE ASSEMBLY

It helps the hinge to tilt up and down by rotating along a axis.

REINFORCEMENTS

Reinforcements are used for balancing the weight loss.

HOOD OUTER PANEL

It is used for covering hood inner panel and engine.it provide a good style to the car.

HOOD INNER PANEL

It supports the hood outer panel.emposses are provided on inner panel to dissipate forces in different direction.also in the inner panel latch striker and hinge assembly is placed.

PARAMETERS IN HOOD DESIGN

MASTIC DATA

Mastic data should be provided in between hood outer panel and inner panel to achieve better NVH range ,to avoid the spot weld,to maintain the upper hood surface regularity.

EMBOSS

Emboss is created in such a way that when force induced in the middle of the hood which directly transmitted to the hinge point to provide better safety.if this type of emboss is not provided the force transmission towards the centre of hood or vehicle which cause serious damage.

LATCH TRAJECTORY

Position between hinge and striker are found by taking centre of axis of hinge as centre of the circle drawn through the striker distance as the radius. It is positioned tangent, so that perpendicularity is obtained.

MANUFACTURING PROCESSES

HEMMING

Hemming is a technology used in the automotive industry to join inner and outer closure hood panels together. It is the process of bending/folding the flange of the outer panel over the inner one. The accuracy of the operation significantly affects the appearance of the car’s outer surfaces and is therefore a critical factor in the final quality of a finished vehicle.

Hemming is performed in order to:

• Achieve a better final geometry in the vehicle´s part
• Add resistance and rigidity to the part
• Allow a safe handling of the part

DEEP DRAWING

Deep drawing is the process of converting blank of sheet metal into a cylindrical containers with a flat or hemispherical base.It is combination of metal forming process & sheet metal process. If the ratio of height to diameter of the product is greater than 0.5 then this drawing operation is known as deep drawing. It basically consists of die, punch, blank holders.After the application of drawing force, the blank of material forms & takes shape of the punch or shape made onto the punch.To avoid frictional resistance between blank & die, the lubricant is used.