Week 8 - Challenge 5 - Core & Cavity Design
AIM:
To create a switch bezel from the given A surface by considering a thickness of 2.5 mm and also creating core and cavity blocks for it.
PROCEDURE:
A class surface:
The input of the product designer is in the form of the A- class surface. The job of the product designer is to create the B and C surfaces keeping all the aspects for the mold.
Class A is
1.Visible surface and aesthetic look
2. surface with textures
3. Surfaces provided by customer( OEM)
4. Dont have any features like (rib, snap, bosses,etc) on class A surface.
5. Class A surface is made from scanned data with different softwere likr alias etc.
6. Surfaces which is having curvature continuity is called as class-A.
B Class surface:
Class B surface:
1.invisible surfaces.
2.surface mostly dont have textures
3.Surface needs to be ctreated according to the Class-A surface.
4.Having all features(Rib,boss,snap etc) in B-side surface only.
5.Surface which is having tangent continunity is called class-B
C class surface:
Class C surface has swep along the boundary Class A surface with respect to the tooling axis direction with a draft angle of 3 degrees.
Final switch bezel component:
Tooling axis:
1. To create the tooling axis, We need the proper orientation or View that gives the correct features and draft available in the component.
2. So here the component view from the Z direction gives the proper view for the tool to see the features present in the geometery.
3. To create the tooling axis from the Z direction we need the tooling axis from the Z direction we need the tooling axis from the other X direction since it gives the draft available at the slanted part.
4. The tooling axis created from the X direction by following steps
1. The base surface is extracted.
2. Then the center point is created using the point> on the surface at 0
3. At the point created the axis system is created
4. After that switching the view of the model to the X direction and creating the tooling axis.
using the intersect in ZY plane to get the boundary lines.
Then the lines are created along the slant surfaces.
Then these two lines are bisected to get the tooling for the X or final
1. Next, switching in the y direction and intersecting the switch bezel part in Zx direction to get the intersecting lines.
2. Using the axis center point, a line is drawn in sketchg mode and it is constrained at the angle of 4 degrees.
3. At last, both the lines are bisected to get the final tooling axis.
Draft analysis:
Click the draft analysis icon:
1. The draft analysis dialog box is displayed. it gives information on the display (color scale), the draft direction, and the direction values.
2. The draft analysis. 1 dialog box showing the color scale and identifying the maximum and minimum values for the analysis is displayed too.
Core and cavity design:
The Mould core and cavity are shaped sections in either half of the mould tool which give the plastic product its final shape.
The hot molten material is injected into the core and cavity and then sets hard into shape. The design of the core and cavity is essiential in the correct formation of the product. The sequence of events during the injection mould of a plastic part is called injection moulding cycle.
The cycle begins when the mould closes, followed by the injection of the polymer into the mould cavity.
A core is usually made of the best quality sand and is placed into the desired position in the mould cavity. core prints are added to both sides of the pattern to create impressions that allow the core to be supported and held at the both ends.
Core:
1. The core design is started with extracting the parting surface that becomes the datum for the core and cavity. The parting surface in most of the cases is kept at the B class surface to avoid close and tight contact between the core and cavity.
2. At first, the A- Class surface is extrapolated with some length and later it is trimmed with a C surface
1.This A and C surface again trimmed with the B surface to form the core face.
fig- parting surface with a component area
2.Now, the final core block is made by drawing the boundary sketch and extruding it along the tooling axis direction followed by the filling and thickening.
Cavity:
1. The cavity is the part where the injector and filling of the molten plastic happens. The cavity block is prepared by thr first extruding the outer bondary along the tooling direction.
2. This outer surface is trimmed with the B class surface and then it is filled and thickened.
Parting line and Parting surface:
A parting line, in the industrial casting of molds, is the borderline in which draft angles change direction.That is it is the dividing line that splits the core and cavity halves of a molded line that splits the core and cavity halves of a molded part. it is sometimes a strating point for the mold parting surface.
Here intersecting the parting surface,core, and cavity across the ZX plane gives the intersecting line that tells the partring line.
Parting surface:
The parting surface of mould are those surfaces of both mould plates adjacent to the impressions which butt together to form a seal and prevent the loss of plastic material from the impresssion . the parting surfaces of the mould are those portion of both mould plates, adjacent to the impressions, which butt together to form a seal and oprevent the loss of plastic material from the impression.
Conclusion:
Core and cavity blocks for the switch bezel have been successfully created.
FEATURE TREE:
