Hood design-Week 2

DESIGNING A HOOD FROM THE GIVEN INPUT DATA IN A NX CAD:-

HOOD:-

The Hood or Bonnet is a component act as closure to the Engine compartment. As we see from our eyes the hood is a normal component to close the engine compartment but the thing is not like that. The hood is one of the well engineered component in the Automotive cars.

The Opening of the hood also have some conditions because the Height of the Human varies across the globe.So the average height of the Indians is 5 Feet but the Europeans average height is above 6 feet.While they are working on the Engine Compartment the Hood should not to distrub by hitting on the head so this case we need to adjust the Height of the Supporting Rod and there should some angle maintains for opening of the Hood.It will varies based on the Country

%One Important thing about placing the Supporting rod. It Should be placed opposite to the Battery compartment. Then only it wont distrub while removing the battery.%

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The Hood contains the Six component they are

• Hood Outer Panel
• Hood Inner Panel
• Hinge LH
• Hinge RH
• Strikers
• NVH (Noise Vibration Harshness)

Now have a look on those components.

INNER PANEL :-

OUTER PANEL :-

STRIKER :-

HINGE :-

NVH:-

Noise Vibration Harshness is a material attached with the components of the Hood these material will absorb the Noise which is happening in the Hood.So we use this to reduce the Noise.

Design Consideration of the Hood:

While we design a Hood we must have a look on some important parameters.

• Following the Master section
• Pedestrian Safety
• Proper Closure
• clearance for the Mastic glue

Master section is a predefined sketch provided as a input with the design considerations and the values.

Based on this we need to make a inner panel.

Pedestrian Safety:-

Most Important factor design should consider the pedestrian safety also.

While Accident the pedestrian head should impact with the Hood,At that time to avoid the major impact we should make the inner panel cutouts to avoid the heavy impact on the pedestrian head

These cutout helps to make deflection while impact by the pedestrian This engineering feature helps to give less impact on the pedestrian head.

PROPER CLOSING :-

The Important work of the Hood is to be in proper Closing condition.For that having some important parameters for the closing.The Latch and striker helps to close the hood. For the latch and the striker should follow the same axis.

Latch:-

This is Latch. It attached with the Body of the car and It allows the striker to make lock.

These Latch and striker should placed on the same axis for the Proper closure,if not the axis Hood will Not closed in Proper way.

How to Draw Hinge Axis.

1. Draw a Line Between Hinges and mark the mid point of the Line
2. After marking, Draw the sketch (Circle) on the point.( Circle radius would be varies based on the positioning of the striker)
3. Create the tangent line to the Circle
4. Finally Make the striker perpendicular to the Tangent line

Mastics Glue and Hemming:-

Mastic and Hemming both are the Joining process Followed by the Automotive Manufacturer.The Outer panel and the Inner panel joined by the Hemming Process and the Mastic glue.

Hemming is the process of folding the Edges of the Outer panel for holding the Inner panel. This Hemming process is also having the some design considerations that we must follow.The both 0.2mm is an area clearance for the HEM GLUE.

MASTIC GUM :-

Mastic Glue or Mastic sealent helps to join Outer panel and Inner panel.It Will be hardened for better sticky.

RELEIFS:-

These Edges are used for Stress releifs.

MY MODEL:-

INNER PANEL :- (0.75 T)

The Inner Panel emboss have some Unbeleivable engineering feature. say for eg: Energy get coming into the panel even it is a air, or Impact with another car(accident).The role of the Embosses will collapse the Energy Flow inside the panel by the same time protect the Passengers from major injuries.

OUTER PANEL :- (0.75 T)

The Outer panel is a Hood cover it Should be have a aesthetic look . Hemming is given to outerpanel only to hold the Inner panel.

OUTER PANEL WITH INNER PANEL :-

WITH HINGES AND STRIKER :-

These Hinges and the Strikers are mounting on the Reinforcements.(Reinforcement adding strength to the Component).

CLIP SECTION VIEW OF THE MODEL:-

DRAFT ANALYSIS:-

THE INNER PANEL MANUFACTURED BY THE STAMPING PROCESS SO WE NEED TO CHECK IF THE COMPONENT ARE MANUFACTURABLE ARE NOT USING DRAFT ANALYSIS.(DRAFT ANGLE WITH MINIMUM 7DEGREE) HERE I MAINTAINED WITH 10DEGREE DRAFT ITS CLEARING WELL SO ITS SUITABLE FOR MANUFACTURING