Hood design-Week 2

HOOD DEFINATION

The hood or bonnet is the hinged cover over the engine of motor vehicles that allows access to the engine compartment, or trunk for maintenance and repair. On front-mounted engine cars, the hood may be hinged at either the front or the rear edge, or in earlier models, it may be split into two sections, one each side, each hinged along the centerline. A further variant combines the bonnet and wheel arches into one section and allows the entire front bodywork to tilt forwards around a pivot near the front of the vehicle.

HOOD- DESIGN METHODOLOGIES

1- To understand the requirements and prepare the master section.

2- To prepare the concepts or approach to make the final design.

3- List out the tool we are going to use.

Hood Componentes-

1. Latch- A hood latch is a very simple component. It's basically the fastener that keeps your hood closed shut. This latch ensures that your hood is securely connected to your vehicle and that it doesn't pop open unexpectedly. When tension is applied to the cable from the hood release handle, it pivots the secondary latch, which pulls away from a retaining seat located under the hood. By design, the secondary latch then releases the hood a few inches before a safety latch takes over.

1. Latch Trajectory motion- While opening or closing the hood, the latch must be perfectly aligned to the fixing or striker point. For that, the latches trajectory must be perpendicular to the hinge axis.

1. Mastic data- A mastic sealant data is used to fix or combine the hood outer panel and hood inner panel. They can provide thermal and acoustical insulation, and may serve as fire barriers. They may have electrical properties, as well. Sealants can also be used for simple smoothing or filling. They are often called upon to perform several of these functions at once. A sealant has three basic functions: It fills a gap between two or more substrates; it forms a barrier through the physical properties of the sealant itself and by adhesion to the substrate; and, it maintains sealing properties for the expected lifetime, service conditions, and environments. The sealant performs these functions by way of correct formulation to achieve specific application and performance properties.

1. Embossing Definition- The metal sheet embossing operation is commonly accomplished with a combination of heat and pressure on the sheet metal, depending on what type of embossing is required. Theoretically, with any of these procedures, the metal thickness is changed in its composition. A metal sheet is drawn through the male and female roller dies, producing a pattern or design on the metal sheet. Depending on the roller dies used, different patterns can be produced on the metal sheet. The pressure and a combination of heat actually "irons" while raising the level of the image higher than the substrate to make it smooth. The term "impressing" refers to an image lowered into the surface of a material, in distinction to an image raised out of the surface of a material.

1. Deep drawing- Deep drawing is a manufacturing process that is used extensively in the forming of sheet metal into a cup or box-like structures. Pots and pans for cooking, containers, sinks, automobile parts, such as panels and gas tanks, are among a few of the items manufactured by sheet metal deep drawing. A deep drawing of sheet metal is performed with a punch and die. The punch is the desired shape of the base of the part, once drawn. The die cavity matches the punch and is a little wider to allow for its passage, as well as clearance. For many calculations, the sheet metal thickness is assumed to remain constant. However, there are changes in thickness in certain areas, due to the forces involved.

1. Hemming - Hemming is a sheet metal forming process in which sheets are joined by bending it usually to 180°. Automotive body panels and automotive parts such as deck-lids, trunk-lids, doors, hoods, and tailgates are formed by hemming processes.

1. Draft Analysis- 5 or 7 degrees of draft analysis is made to the inner panel to find any negative draft. this process is done because we need to develop and submit a positive design to the manufacturers. we can see that there are no negative drafts by the inner panel, hence the design is positive and ready to manufactured.