Hood design-Week 2

                                                 HOOD ASSEMBLY DESIGN

AIM : To create and assemble the hood inner panel and outer panel and their reinforcements by following the design rules and master section.

SOFTWARE USED : NX CAD 12.0

DESCRIPTION : Design Hood outer panel, inner panel and the necessary reinforcements by following the Master section mentioned with the design parameter  and a detailed report about the Hood Design which includes a detailed explanation about hood and its components, Latch trajectory, Mastic informations , Emboss definitions, manufacturing process like deep drawing and hemming, and all the parameters followed in the design.

HOOD AND IT'S COMPONENTS : Car hood is a hinged cover that does rest over the engine in a front-of engine car. A latch is provided under the hood in order to prevent accidental opening and a good locking mechanism during driving. Purpose of hood is to provide access to the engine and battery for repair and maintenance. It also protects these parts from external damage,direct sunlight and dust.

COMPONENTS :

Hood outer panel 

Hood outer panel is the skin data or we called A surface which we used to develope the rest parts.

Hood inner panel :

The inner panel provides strength and supports the outer panel. It is where hood balancer and hinges are attached.

Hinges :

Hinges allow the hood to rotate about a fixed axis for opening and closing the hood part. One part of the hinge is fixed with the engine compartment, where other part is connected to hood.

Lach and striker :

Latch and striker mechanism is provided to lock the hood, in order to prevent accidental opening of the hood during driving. The latch is present on the engine compartment while the striker is attached to inner part of hood.

Support rod :

It is a device that supports the hood in open position. It is also called as hood balancer rod.

Latch trejectory :

 It is the path along which the hood rotates during opening and closing movement. The striker on the hood follows this path while opening or closing the hood, which is along circumference of a circle with center at the hinge axis. This path is nothing but latch trajectory. It is a very important aspect in hood design, in order to decide hinge, latch and striker position points.

DESIGN METHODOLOGY :First the inner panel is designed from the given master section using the various commands and features. We create the embossing using the offset surface from the original master section. Similarly, we create the cuts on the emboss by sketching and using trim surface option.Then the outer panel is designed from the same master section. Here we are supposed to provide the hemming to outer panel. The parameters of hemming are taken as per given values.Now, on the inner panel, the embossing for hinge and striker are produced by considering their respective dimensions and assembly positions. First the emboss for hinge is created and then by fixing the hinge into its position, we draw an axis passing through both side hinge axes to form a common axis. And then we position the striker such that it will move along circumference of a circle whose center is at midpoint of the common axis. Thus, position of striker is decided and we can create emboss for the same.Using the hinge emboss we created, we can create our hinge reinforcements by creating new parts in the assembly itself.

• Data Povided –

Outer Panel Thickness – 0.75mm

Inner Panel Thickness – 0.75mm

Reinforcement Thickness – 1.5mm

MASTER SECTION AND OTHER DATA

FINISHED ASSEMBLY :

CONCLUSION :

Thus the hood/bonnet of car has designed and assembled by using nx-cad.