Week 9 - Attachment Feature Creation (Ribs & Screw Boss) - Challenge 1

TO DESIGN A RIB AND SCREW BOSS OF A DOOR HANDLE BY USING CLASS A SURFACE

AIM:

• To design a door handle Plastic component through the given Class-A surface by creating a tooling axis and draft analysis of the given surface and also design a rib and screw boss.

DESIGN PROCEDURE:

• To setup the class-A surface and to creating a tooling axis
• add draft angle
• To create a base surface of model
• To create a B-surface
• To create a C-surface
• To use close surface for creating a solid part model

CLASS-A SURFACE:

TOOLING AXIS:

• Tooling axis can be classified into two methods

1. Bisecting method:

• It is defined as the direction in which the Mould/core and cavity open. Selection of the direction of the tooling axis depends on the ease at which components can be easily ejected.
• By analyzing the component, the most easily eject able direction is somewhere close to the Z direction, (might be inclined to it) so we have made a sketch on the YZ plane of Axis System) to create a bisecting line considering the 2 faces which might be difficult to be tooled.
• To bisect the lines and point by creating a tooling axis.

2. general and reference method:

• It can create based on the origin and calculating manufacturing process based on the point orientation for setting up tool.

DRAFT ANALYSIS:

• The Drafting analysis was performed on the class-A surface by using the Feature Draft Analysis
• Using this command, the compass was set on the main tooling axis and the Draft angle was changed to 3 degrees.
• 

• CREATING CLASS-B SURFACE:

  • To offset the class-A surface along 2.5mm for to create a B- SURFCAE.
  • Surface Gaps can be filled by using a fill tool and multi sectional tool
  • 
  • B-SURFACE

  • CREATING C- SURFACE:

    • To use multiple extract tool on the class A surface
    • The extract boundaries can be sweep at 90 degrees to the reference boundaries up to required length
    • 

C-SURFACE

SURFACE MODEL OF A DOOR HANDLE:

Without rib and screw boss

SOLID MODEL OF A DOOR HANDLE WITH RIB AND SCREW BOSS:

TREE SHOTS:

DESIGN OF RIB AND SCREW BOSS:

• To design a rib based on the requirement of a component and to add set of calculations for construction of rib and screw boss

Design Principle for Rib Creation

• Ribs are thin wall protrusions that extend perpendicularly from a wall or plane.
• They are usually found in clusters offering support to a plane that would have otherwise been too thick, but can also be stand-alone support for a single wall.
• They are commonly used to provide additional support and strength to a part. Thickness and location are essential to rib design.
• First, the base surface where the rib has to be created is extracted using the Extract command. A positioned sketch is created and the profile for the rib is drawn.

Next, the profile is extruded, to find the height(h)=Wall thickness * 5

=3*5

= 15 mm

• Therefore, the height is 15 mm
• The extruded surface is thickened,

Thickness of rib(w)=0.4*t

=0.4* 3

=1.2mm

• Therefore, the thickness of the rib is 1.2 mm
• Draft angle can be set into 0.5 degree
• 

CONCLUSION:

• To use class-A surface and create Tooling axis, Draft analysis were performed.
• The solid component was created from the surface model.

ISO CONSTRAINS OF RIB AND SCREW BOSS SKETCHES:

Rib iso sketch

Screw boss iso