b Some things to note- The thickness of the product is made as thin as possible as possible, as evenly as possible.. b Solution design bo corner: DOCSIS requirements thickness uniformity
Trang 1OTHER NOTICES GEOMETRIC SHAPES OF PRODUCTS
Trang 21) Corner exit mold
- As well as the outer surface of the product must have certain taper towards the open mold
- - In the short mold core or cavity shallow (less than 5 mm) cone angle of about 0.25 ° at least each side
- Cavity and core depth increased from 1 to 2 inches (25.4 ÷ 50.8 mm) cone angle should increase to 2 ° per side
- When not designing drainage angle or improperly designed mold, the product will be trapped in the mold or if the matter ejected in the product surface will also fail
Trang 3- Graphs choose beveled corner:
Trang 4- The formula for calculating the beveled corner:
Trang 52) Thickness
a) Effective design:
- Shortening the cycle time of injection molding and mold making - Avoids errors on the product
- Increasing time filling shorten cycle time injection molding and mold making
- Reduce the cost of products and mold
- Material savings while bringing efficiency
- Avoid defects such as warping, stomatal
Trang 6- Product thickness directly affects not only the stiffness, electrical insulation, heat resistance.
- First, while increasing the thickness of the cold cycle time increases
- Second, section too thick will create an empty bladder, airbags and dents
- The best heat transfer when products have uniform thickness to minimize warping
Trang 7b) Some things to note
- The thickness of the product is made as thin as possible as possible, as evenly as possible
- If the product is not strong enough, you can:
- + Increased thickness
- + Using other materials have higher durability
- + Create stiffening ribs or the glide angle for increased reliability
- + Can restricting disabilities by designing the transition
Trang 83) Corner
a) The effect of design:
- Reduce stress concentration
- Assist products are cooled more evenly
- Reduce the possibility of warping
- Reduce the flow obstructing makes plastic fills the cavity better b) Solution design bo corner:
DOCSIS requirements thickness uniformity of products
Avoiding product design with geometric shapes asymmetrical
Trang 9c) Some caution when designing motherboards corner: The radius of the boron should range from 0.25 to 0.6 Recipe: R = r + T
- The disabled often encounter:
Trang 104) Tendon
a) Effective design:
- Increasing product durability.
- Increased resistance to bending of the product.
Trang 11b) Design Nearby:
- Designed so that tendon thickness as thin as possible products
- The geometry increases tendon strength: thickness, elevation, taper angles are related to each other Nearby inclination of each side about 10
- The reference parameters when designing Nearby:
Ribbed reinforcing the flat plate bending:
t = (0.5-0.8) T
h ≤ 3T
r = (0.25-0.5) T
Φ = (0.5-1) °
S ≥ 2T
Ribbed reinforcing the corner plates
A = (0.5-0.7) T
B ≥ 2T
C ≥ 2T
D ≥ 2T
Trang 12c) a few things to note:
The thickness of the tendon should not exceed half the thickness set tendon
The thickness of the tendon should not exceed half the thickness set tendon
The ribs should be designed in parallel, the distance between the tendon should be at least equal to 2 times the thickness The ribs should be placed along one direction to achieve good rigidity
Can replace corrugated folds to increase the rigidity and aesthetics
place transition should be a point to ensure the hardness and resistance to stress for the product
Ribbed reinforcing: for stiffening the corners, sides, lugs protruding
Trang 135) Convex
- Lugs protruding on products used to screw or latch combined with holes in the assembly process
Thickness smaller lugs protruding thickness 0.7 times the distance between the two put the paw paw twice bigger product thickness Transitional outer radius should equal 0.25% thickness or at least put the lug by 0.4 mm to reduce stress
- The outer cone angle at the side should be a minimum of 0.50 and smallest cone angle so as to ensure the drainage 00:25 mold The lugs protruding put away the product design should add stiffening ribs
Make a right foot concave ring lugs to avoid the concentration of material
Trang 146) Loss on products
a) Loss not transparent:
- The depth of the hole should not exceed 3 times the diameter
- A good design is the thickness of the hole is always equal and no sharp corners
Trang 15b) hole through:
- The distance between two holes or between the hole and the outer edge should be equal to twice the thickness or twice the maximum size is measured the circumference of the hole
- When the distance between the holes are too small or complex affecting the casting process can change the design for a better fit
Trang 167) Product Design threaded
a) Minutes lace shape:
Thread on the plastic parts manufactured by means of injection molding
Deformation threaded sometimes designed not follow any standards
Thread round profiles are also often used on plastic parts
b) The note at foot lace design:
Foot radius lace and lace to the largest peak can to reduce stress
All lace segment should create a smooth passage to avoid damage resulting lace lace smuggled in during use -You Can use rubber gaskets for joints to be sealed over
• Do not designed lace with less than 1 mm steps (32 thread / inch)
Trang 178) UnderCut
-Undercut Are detailed, textured on products that have different directions stripping with stripping direction of the product
Is the top product -Undercut caused difficulty parting
-Undercut May be located outside or inside the product
The note when designing undercut:
- Avoid too complex undercut design
- Thickness no greater than 0.7 times undercut the thickness of the product at the place set undercut
- The edges of the mold containing boron should undercut the supply and do
inclined to undercut can easily escape
- Part undercut when removing them should be hot enough to be able to stretch and return normal back then