Hood design-Week 2

CAR’S HOOD DESIGN

OBJECTIVE:

To design the hood by utilize the consideration of hood.

INTRODUCTION:

The hood is opening body panel which covers the engine in a front engine vehicle and it also consider as a another type of door.in some other countries they called as bonnet.it desipite the energy outside rather than inside of car body.

COMPONENTS OF HOOD:

• OUTER PANEL-The hood outer panel is just like a metal cover.
• INNER PANEL-The hood inner panel improve the strength.
• STRIKER-which is lock & unlock purpose for hood.
• HINGE-we use hinge for motion purpose.
• Support rod or gas stay-For opening or changing the angle through support rod or gas stay.

DESIGN METHODOLOGY:

With the help of master section we can design a hood,master section means a design’s sketch.

Hood stay:

A hood stay is an apparatus for engine room of car,which can safely keep on hood in open state. we consider india human’s height avg 5.5ft but in euro 6 ft through this we change that opening angle.if we make hood angle lesser,the customer hits the striker,it’s tends to injury.

PURPOSE:

An automotive engine hood is opened for the purpose of

• Inspecting the engine room
• Changing cooling water /engine oil
• Changine parts
• Making repairs

TYPES OF HOOD STAY:

TYPES	BENEFITS	DEMERITS
SUPPORT ROD(support the hood by rod)	· LOW COST · SIMPLE DESIGN	· RUST CAN FORMED
GAS STAY(support the hood by actuater,which is actuating by gas)	· NO MAN POWER REQUIRED	· HIGH COST

SUPPORT ROD GAS STAY

NOTE:

• The support rod doesn’t have straight,if it have straight it may wobble.so,it’s in shape or curve it become rigid.
• That support rod curvature less than 35mm,if that curve higher,it act as bending moment through hood’s weight.
• The grommet(the support rod will attach in rest condition)and rod must have parallely.
• In gas stay,cylinder outer dia must have 18mm and rod outer dia must have 8mm.(standards)
• Stud ball(which used to fix both side),creating a design consider by standards(TT and 90456-AD000)
• In gas stay,To improve a we add bracket.

REINFORCEMENT:

If we adding some extra material into parts,actually it lose their strength in that particular region.so make that balance we add a reinforcement.

If we consider latch and striker adding to hood ,it tends to lose their strength .so,we add a latch and striker reinforcement.it compensate that loses.

STIFFNER PAD:

It has placed b/w outer panel and inner panel.during motion that outer panel may vibrates,to reduce NVH level we add stiffner pad.

It doesn’t have any predefined shape.

MASTIC SEALEN:

Mastic sealen is used to make a joint b/w outer panel and inner pannel and also used to improve stiffness of area.one mastic seal gives stiffness around 80mm dia. mastic sealen will occupy 4.5mm gap.

EMBOSS:

If the vehicle may get collision,that force go straight.to despite the forces towards hinge.we create a embois.

NOTE:we make embois along y direction.so, that the force reduce equally.it will helps to reduce the injury during collision.

HEMMING:

It is the tool,which is alternative for joining two different sheet.te hemming process were achieved by rolling.for rolling process use 3 to 4 rollers.we want to give relief to that 4 corners.

PEDESTRAIN RATING:

The most important things is safety.so,there are times that pedestrain will be hit by the car.while the head laid on the hood that specific portion should absorbs the engergy instead of resisting to prevent causes.

WRAP AROUND DISTANCE:

When the car crashes on a pedestrain the whole body wraps around infront of car and the head lies on the hood or windscreen.

The distanc on which the head impact the car from the ground is known as wrap around distance(WAD).

Child’s head impact zone:1000mm to 1700mm(3.5kg)

Adult’s head impact zone:1700mm to 2100mm(4.5kg)

Latch trajectory:

The two hinges should placed in same axis.from the center of this axis,we draw a circle like touching the striker lock point.center of that lock point should have perpenticular to that hinge axis.that means only hood close and open perfectly.

HOOD DESIGN:

Conclusion:

Thus, the hood were designed by condering all the important factors and analysis also conducted.