Week 9 - Project 1 - Door Applique Design with Engineering Features

AIM:

To create a solid body of a given door Applique and to create the locaters and heat stakes on it sas per standards.

INTODUCTION:

Heat staking

Heat staking is a pulsed- heat process to join two or more parts out of which one at least is made of plastic.The process is to feform the plastic matwerial using heat and force at a set process time .The bond is made by partially de-forming the plastic part in order to fix the other.

Heat staking makes it easy to bond metal to plastic and is commanly used in high volume/low cost application such as automative,IT and consumer appliances/

In manufacturing of thermoplastic components,it is often necessary to join the thermoplastic to a part of a dissimilar material material ,weather it can be a metal,dissimilar material or the other material .Thermal staking is an assembly method that uses the controlled melting and reforming of a plasticstud or boss to capture or lock another plastic or a metasl component of an assembly in place.The plastic studs protude through the holes in a component to be locked in a place.The heated thermal tip contacts the top of the studs,which melts and fills the volume of the tip cavity to produce the heat ,locking the component in a place.The progressive melting of the plastic under continoues pressure forms the head.When staking the right combination of heat and pressure for the application is critical.

Advantages of heat stakes:

• Similar and dissimilar materials may be joined:metal,plastic,metal to plastic.
• Accurate control operating within a small process window.
• Local heating resulting in no damage to surrounding materials.
• processing of glass-filled materials.
• No mechanical vibration.
• Many heat-stakes shapes possible through custo, desgined tools.

PROCEDURE:

1)Tooling axis
Tooling axis is nothing but the duirection in which the core and cavity opens and closes . Design engineer works is to analyse the class A surface and find out the besy possible tooling direction keeping in mind all the draft angle is with respect to the tooling axis so that the component can be easily ejected from the moulds.

2)A Class surface

In automative design,a class A surface is any of aset of freedom surface of high efficiency and quality.Although,strictly ,it is nothing more than saying the surfaces have curvature and tangemcy alignment- to idealaesthetical reflection quality.Many people interpret class A surface to have G2(or even G3) curvature continuity to one another.Class A surfacing is done using computer_aided industrial design applications.Class A surface modellers are also called" digital sculptors" in the industry. Industrial develop their design stylling through the A- surface,the physical surface the end user can feel,touch ,see etc.

3)B Class surface creation

Represent internal and functional surfaces.This cluster exemplary includes derived surfaces created by offset operation from class A surfaces to define the thickness of material.In this file important to link class B surfaces geometrical to enable an adaptation to class A surfaces automatically in case of styling change.

After creating the tooling axis,B surface is to created which is nothing but the surface parallel to the A surface .B surface contains all the fillets and the edge which the A surface contains.

4)C Class surface creation

Class C surafce is swept along the boundary of the class A at an angke perpendicular to the class A surface with respect to the tooling axis direction with a draft angle of 3degree.

5) Joining Class A,B and C surface to get a closed surface

After finishing all the 3 surfaces,join the class A and class C surfcae together using the join command .Now , the joined surfaces are then trimmed with class B surface to form a closed surface.

6) Draft analysis

The Draft analysis command enables you to detect if the part you drafted will be easily removed. This type of analysis is performed based on colour ranges identifying zones on the analyzed element where the deviation from the draft direction at any point, corresponds to specified values.

Draft angles are very important in thermofoming product design.If the product is formed onto a female or negative mould,it shrinks away from the mold sidewalls .As a result ,true femaleor negative products can be with vertical thermoformed with vertical walls having zero draft angles.

7)Creating 2 and 4 way locators and heat stakes:

4-way locators mean you prevent movement at 2 axis (+x,-x,+y and -y) on the plane.Generally you have cylindrical pin on the fixture and circular hole at workpiece part.

2-way locators mean you prevent movement only at 1 axis on the plane.

While creating the locators we need to follow the design rules to create the ribsin order the sink marks on the components.

Heat Staking ia pulsed-heat process to join two or more parts of which one at least is made of plastic.The process is to deform the plastic material using heat and force at a set process time.The bond is made by partially de-forming the plastic part in order to fix the other.

Once done with the design of locators and the heat stakes we need to design the counter holesin the mating parts with standard clearnces as shown in picture below.

Result:

• Class A,B and C surface as per the automotive standards using catia V5 software.
• Draft analysis was performed for the built model and it could be seen that the draft was under permissible limit for the manufacturing of the component.
• Ribs were created for the component as per the design rules.