Housing Design

Industrial Housing Design

for your Electronics

A Case Study: from concept to product

Dr. Jürgen KienhöferCEO Wireless Cables Inc.www.aircable.net

Presentation at thewww.makersfactory.comDecember 2, 2011

Wireless Cables Inc.

• WCI makes intelligent, long range Bluetooth modules

• WCI designs products using these modules

Housing Designs over the years

Workflow Housing Design

• Product design ideao how does your final product look likeo how is it used

• Electronic parts determinesize and shape

Workflow1. electronics modeling2. housing concept3. design for the mold4. prototype before production

1: Electronic Modeling

• hold electronic in place• design actuators• ergonomics and use case• lights or displays• sensors and power connectors

example: AIRcable Serial5X

2: Housing Concept

Simple: a square box with holes

• multi part design: A-side, B-side: d-cide

• joining parts

• hinges

• thickness

• shrinkage and other blemishes

Joining Two Parts

• Screws• Glue• Hooks and Snaps• Friction• Ultrasonic Welding

3: Design to the Mold

What is a Mold?It's about costs:

simple straight pull mold designif you have to: side action molds

first prototypefiles to manufacturing

An Injection Molding Machine

watch the video

Injection Mold Cavity and Core

Click image to see the machine producing this part

© OME International Injection Molding, with permission

Watch a bucket being formed...

Design for the Mold

DRAFTING• 0.50 draft is minimum• 20 is safe, 30 for light

texture, 50 for heavy texture• reduce stress to take outUNDERCUTS• molds are made out of two

pieces: A-side and B-side• side action

COSTS MONEY!(a lot)

UNDERCUT (cont.)

Example: AIRcable Serial5X

• snap together design• no undercuts• matched mating parts• uniform thickness• Polycarbonate• transparency

Design Process with Solidworks

start with a solid block

add hooks and grooves

shell the part to get uniform thickness

cut holes for the hooksdrafting for snap action

cut holder for the connectorand the screws

fillet for easy mold pull out

Design Process with Blender

??? (to be honest...)

wire frame, give thickness, cloth design

Design Process "AIRcable USB5"

solid block with domed feature

cut and shelled

final two part housingwith friction fit

Materials: most often used

• ABSo cheap, easy to mold, paintable

• Polycarbonate (PC)o does not break, strong, UV resistent o transparent and glass clear

• 33% glass filled Nylono strongest material, solvent resistanto glass fiber makes it heat resistant as wello shrinks quite a bit during moldingo use for sensors and valves

Decide early: the mold is made for ONE material

Prototype

Ergonomic housing design is a challenge!you must make a prototype to test

• electronic fits, actuators work, lights, display• usability, show to others• ease of assembly, time for workers

Quick prototypes: SLA (UV cureable resin), SLS (Selective Laser Singering), FDM (Fused deposit modeling), Polyjet (Photopolymer), CNC (Machining)

4: Finishing

• Texturecreated via sand blast of the mold or polish

• PaintingABS can easily be spraypainted

• Printinglogos via silk screen print, epoxy

• Anodizealuminum gets scratch resistance and color

• Stickersmake indent for sticker

5: Assembly

Putting it all together:

Packaging designPaper insetUPC bar codeFCC and other certifications (UL, CE, ...)

Summary

Topics covered• electronics design• model the inside first• housing design concept• use collision detection• make prototype and test design• tooling, prototype run• manufacturing• packaging• sell your product on the web

ResourcesPlastic Wikihttp://www.plastics.inwiki.orgProspector Plastics Datasheet http://www.ides.comMaterial Properties and Injection

Molding, calculate the detailshttp://www.efunda.comMaterialshttp://www.matweb.com

Rapid Injection Molding http://www.protomold.comhttp://www.quickparts.com

Polyjet prototyping C-Ideashttp://www.buildparts.comBarcodeshttp://www.nationwidebarcode.comCAD Softwarehttp://www.solidworks.comhttp://www.3dcontentcentral.com

http://www.blender.orghttp://www.123dapp.comOnline Machine Shophttp://www.emachineshop.com

Commercial Injection Moldinghttp://www.ome-mould.com

Questions?

or email me:juergen@aircable.net

this presentation is available online: http://goo.gl/Qq1Mj