Challenge

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

NNobal Nagar29 Aug 2022

Ribs & Screw Boss-

AIM:

To Create the Door Handle Component from the given Class-A surface.
To Create the tooling axis for the given Class-A Surface meeting the requirements of the draft angle.
To Attach B side Features in the component.
To perform the Draft analysis on the model.

CREATING TOOLING AXIS -

The Tooling Direction is basically the direction that the mold pulls a part. The mold is built in two separate pieces, basically. You have a Cavity side and you have the Core side. The Core pulls apart from the Cavity and that's the Dye line or the Tooling Direction.

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 analysing the component the most easily ejectable 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.

Then resultant tooling axis is created using the bisecting method.

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 color ranges identifying zones on the analyzed element where the deviation from the draft direction at any point, corresponds to specified values.

Before going to drat analysis go to customized view parameter >under mesh >check material and then click ok.
Now for draft analyses go to insert » analysis » feature draft analysis.
Use the compasss to define the draft direction.
In the colour scale change the draft angle to 3 degree.
The component changes to green in indication of passing draft angle.
Use running point to check the angle on the component.

CREATING CLASS B SURFACE

Extract the surfaces from the class A using multiple extract and untrim them.
Use Extrapolate to make sure that all the untrims are properly intersected to trim and offset the surfaces to 2.5 mm to create the thickness.

CREATING CLASS C SURFACE

Extract the boundary from the class A surface using boundary command.
Using disassemble tool to divide the boundary as the boundary contains domains.
Use Blend command > Class A And Class B surface Boundary To create Blend between both Surfaces

After getting Blends then Join the output with class A & B surfaces to get final output.

Now open part design workbench and using close body surface create a solid of the component.

CREATING THE RIB

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.

Sketch Used For Rib Creation - (Iso Constrained & Positioned Sketch)

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

=2.5*5

= 12.5 mm

Therefore, the height is 12.5 mm

The extruded surface is thickened,

Thickness,w=0.4*t

=0.4 2.5

=1mm

Therefore, the thickness of the rib is 1 mm

The draft is applied to the sides of the ribs. As per the design rule, the ideal draft angle is 0.5 deg

Then fillet is applied to the faces of the rib. As per the design rule, the fillet can be 0.25 mm.

Now, we have to check for the Rib root thickness.

To check for the Rib root thickness, We have to take an Intersection with the XY plane and the Coin holder component. Once we get to the intersection we have to create a tri-tangent circle at the rib area and measure it. The value must be within 30% greater of the wall thickness.

CREATING THE SCREW BOSS

Screw Boss features are commonly found in injection molding designs. They are used to aid in the assembly of molded parts by providing a channel for a screw. Their primary use is to strengthen holes or slots in the surface present in the part model.

Design rules consider while creating a screw boss

• Thickness

• Draft

• optional radii

• Boss gussets

• Type of ejection

The construction process of creating the screw boss is explained below:

For thickness, the design rule is as follows,

Thickness,w=0.6*T

=0.6*2.5

=1.5 mm

Therefore, the thickness of the boss can be 1.5 mm per side.