Week 12- Final project

DEVELOPMENT OF DOOR TRIM PANEL

AIM :- To create a CAD model for door trim panel's parts by considering the given inputs of class A surface along with master section by following the design rules followed in OEM and tier1 companies.

Objectives :-

• To create individual tooling axis for the parts and perform draft analysis on the class A surface
• To create the class B and class C surfaces from the given class A surface
• To form a solid geometry by combining all the surfaces
• To decide an attachment strategy for the part and create engineering features in reference from the master section provided
• To perform draft analysis on the solid part model with all engineering features
• To assemble all the components togehter to obtain the final trim

Given Data :-

• Class A Surface for Door Trim Panel -

As we know in automotive industry there are complex products that we have to design but this is not possible with simple sketches for that we need Class A Surface.

The A-surface or the styling surface is first checked for any gaps and other issues in its surfaces. This Surface acts as the input surface so any correction to be done should be with approval from the styling team or done by them. A- perfect surface is the one when a boundary is created, the lines are only on the edges of a component and its holes or cutouts as shown below.

Steps Follwed for Completion of Project :-

The door trim panel is created by follwing steps -

1. To check given Class A surafces for any modification.
2. To segregate given surafces into separate part body namely Lower Substrate , Arm Rest , Map Pocket , Bottle Holder.
3. To work individually on each part.
4. To create tooling axis for part.
5. Draft analysis on class A surafce.
6. Creation of class B and Class C surafce.
7. Craete closed body from Class A , B and Class C surface.
8. Follwed same procedure to craete all parts .
9. Then create attachement features for all parts.
10. Then do Draft analysis on final parts and then constrain them for assembly.

ARM REST

• Class A Surface -

1. Check Given Class A Surafce for improvement .

As shown in above image I have improved given class A surface in surafce workbench by using surafce operation such as extract, extrapolation , trim etc.

• Creation of Tooling Axis - For moulding of Arm Rest we need two tooling axis. Some area get cleared with first tooling axis and remaining with second one.
• Class B surface:
• 
• Class C surface:
• 

Final closed surface :

Creation of Flanges on Arm Rest -

From mastersection we get the idea of flanges . I have created flanges on Arm Rest by considering counterpart (Lower Substrate) position.

• Draft Analysis on Soild Body of Arm Rest -

DRAFT : The draft is something that allows the componenet to release or eject from the mold properly. The draft is required on all parts in the direction of mold movement in order to allow parts to release properly. Most parts or applications require a minimum of 1/2 to 1 degree, however , 3 degrees is widely accepted as the norm.

The draft is given in the direction of tooling direction or core cavity opening.

If we don't give the draft to the component it strick to the mold and friction alos act so we get the damage in our part so to overcome this we give some draft angle to overcome this problem.

As mentioned above we have two tooling axis for Arm rest.

Following images give the idea about is it manufacturable or not.

From above draft analysis we notice that given part is not as good to manufcature. There is lot of modification needed. We have to request styling team to improvement in class A at particular areas

MAP POCKET

Class A surface:

Class B surface:

Class C Surface:

• Final Solid Body of Map Pocket with flanges:
• 

Bottle Holder:

Class A Surface:

Class B Surface:

Class C surface:

• Final Solid Body of Map Pocket with flanges:
• 

LOWER SUBSTRATE

Class A Surafce:

Class B Surface:

Class C Surface:

Creation of Dog House

DOG HOUSE -

• The two main purposes of a dog house are to avoid sink marks and to house various other engineering features like screw boss, locators, push clips etc.
• In this case, the dog house is designed to house the push clips and the 4 way locator. The dog house designed for the push clip features a slot on the top face to accommodate the push clip
• The dog house should follow certain design rules which are stated below.

• Doghouse wall thickness at the intersection of the part wall (C) should be 40% or less than the main wall stock (T).
• The height of ( B ) should be between 3.0 – 6.0 mm
• Outer surface of dog house must have a draft angle of 3 degrees
• Inner surface of dog house must have a draft angle of 0.5 degrees

• Creation of Locators

LOCATORS -

• The main purpose of locators is to facilitate proper locking of two components together while assembling and arrest the maximum degrees of freedom possible.
• These locators are similar to guide pins provided in mould.
• The two types of locators used are two way locator and four way locator.
• We have positioned three 4 way locators in our model which meet the rib design criteria.

• Final Solid Body of Map Pocket with Doghouse& Locators:
• Lower Substrate with all engineering features.
• Final Assembly -

For final assembly of door trim panel we have to constarin all parts together.

Following image shows the assembly of push pin with dog house.

In the same way we have to constrain all the parts together.

Following tree structure shows the how all part are constrained.

Final Assembly:

CONCLUSION :-

From this project I have leraned how to create CAD model for plastics parts by considering design rule. By doing this project on Catia V5 , I get very well familiar with part workbench ,surface workbench , Assembly workbench. Also I get confidence in handling different features of all workbenches. Along with this , I get idea of how to design a part by considering manufacturing and assembly aspect. .