DESIGN AND DRAFT ANALYSIS OF SWITCH BEZEL

AIM

The aim is to design a switch bezel and conduct a draft analysis for it using . The Bisecting approach to create the needed tooling direction.

INTRODUCTION

CLASS-A SURFACE: a surface made by the designer which is given as an input to the plastic modeler to work on. It is aesthetic surface and the outer most

surface.

CLASS-B SURFACE: a surface below a certain thickness from the class-A surface is class-B surface. This is the surface that contains engineering aspects of a

model.

CLASS-C SURFACE: a surface that joins class-A and class-B surfaces is class-C surface.

METHODOLOGY:

The concepts used in the model are as follows:

1. Tooling axis
2. Draft analysis
3. Class-B surface
4. Class-C surface
5. Making a solid model from surface.

CATIA Tools used in this model are:

1. Extract
2. Un-trim
3. Trim
4. Extrapolate
5. Offset
6. Edge fillet
7. Boundary
8. Sweep
9. Join
10. Close (part design).

PROCEDURE FOR CREATING THE SWITCH BEZEL

• The given style surface is first checked for imperfections, and if any are discovered, they are repaired using the Trim, Extrapolate, Split, and Join commands.
• Let's go on to the following phase now that the Class – A surface is clean and free of imperfections, as seen in the figure below.

CREATING A TOOLING AXIS.

• The interior trim (switch bezel) must have a nominal 3-degree draft angle when ejected from the cavity of the mould after production.
• Hence the tooling direction is created by considering the above factor and bisecting method is used..
• The class – A's bottom surface was taken, a point in the center was generated, and an axis system was introduced with the current feature deactivated.
• The two inclined lines were then drawn inside the positioned sketch using project intersection along the yz plane.
• Then bisecting lines with the two inclined lines were drawn
• Now repeat the technique throughout the xz plane, but because one side lacks inclined lines, the centre point is used to extrude a line along the z direction, yielding a 5 degree measurement (Tentatively).
• The bisecting line is created and published using these two lines from drawings 1 and 2. (tooling direction)

CREATION OF CLASS – B SURFACE

• The necessary surface, excluding the offset surface, was extracted and then all of the surface was untrimmed to create the class-B surface.
• The intersections between all of the surfaces were then extrapolated.
• The B-Surface was offset to 2.5 mm due to the thickness of the Switch bezel, and the necessary trim procedures must be performed.

Lastly, the appropriate edges were filled to a depth of 12.5mm (15mm-2.5mm). [Fillet values of the A-surface: 15mm, part thickness: 2.5mm].

CREATION OF CLASS – C SURFACE

• Multiple Extract was used to extract the A- Surface outer margins. The curve is then smoothed with the Curve Smooth option to avoid the spots.
• The surface was therefore generated with the following feature parameters using the sweep command:

1. Profile type – Line
2. Subtype – With Draft Direction
3. Guide Curve – Smooth Curve
4. Draft Direction – Tooling Axis
5. Draft Computation Mode – Square
6. Angle – 3 Degree
7. Angle Sector – Positive Downward (1)
8. Length – 20mm

• The margins were then intersected between the surface corners using the extrapolation command, making trimming easier.
• The necessary section of the C – surface was now trimmed away.

CREATION OF CLOSED SURFACE

• Extrapolation (tangent continuity) and Trim surface were used to link the Class A and Class C surfaces together by reducing the gaps between them.
• The specific surface of the Switch bezel was therefore trimmed with the class-B surface from the above-resulted trim surface.
• The component's solid body is then produced by utilizing the Closed Surface command in Part Design to define the part body.

PROCEDURE FOR DRAFT ANALYSIS

• Before generating the Class –B&C surface, the Class –A surface must be checked, and then the solid body must be examined. Both can be accomplished by following the steps outlined below.
• The feature draft analysis is enabled by switching the view mode to custom view parameters – Material mode.
• The compass was then activated and aligned with the tooling axis by sliding the red pointer and locking it in position.
• The nominal value will be 3 degrees, and the component's draft angle will be evaluated by selecting the rapid analysis mode.
• The green color area indicates that it meets the 3-degree draft angle requirement. If not satisfied, the area is measured and then adjusted using the Running point tool to produce a successful draft for the created tooling direction.

CONCLUSION

Finally, the Tooling Direction for the Class – A, B, and C surfaces has been published, and the Switch Bezel has moved on to the next operation – the construction of B-side features.