It was seen that the works of founders of States, law-givers, tyrant-destroyers, and heroes cover
but narrow spaces and endure but for a time; while the work of the inventor, though of less pomp,
is felt everywhere and lasts forever.          - Francis Bacon Preface to a Treatise on Interpreting Nature




The Design of Everyday Things

Every inventor should take this free online course. Learn the basics of design and start observing and applying design principles.



How to Design Breakthrough Inventions

A CBS interview of IDEO founder David Kelley


How to Build a StartUp

In this free online course, learn the key tools and steps for building a successful startup (or at least reducing the risk of failure).

Monday, February 4, 2008

December 2007 Summary

Dr. Mileta Tomovic (of Purdue University's Department of Mechanical Engineering Technology) and graduate students Tamara Novakov and Jui Shyang Liu introduced us to the fascinating technology of rapid prototyping, which creates a prototype model of an invention rapidly (2 – 7 hours) and inexpensively. They have generously made the slides of their presentation accessible.

Embodying your inventive idea in a physical model can help you:

  • visually communicate your invention to investors, colleagues, and customers
  • optimize your invention before manufacture
  • test market your invention on a small scale
  • establish an invention date for your patent application
  • reverse engineer someone else's invention.

One form of rapid prototyping (known as material addition, additive fabrication, three dimensional printing, solid free-form fabrication, layered manufacturing, or computer automated manufacturing) uses a machine, and a description of your invention as Computer-Aided Design (CAD) data, to build a physical model of your invention.

The basic rapid prototyping process has 5 steps:

  1. create a CAD model of your design
  2. convert it to STL format (a format, native to stereolithography CAD software, which represents a 3-D surface of your invention as an assembly of planar triangles)
  3. slice the STL file into thin cross-sectional layers (a pre-processing program adjusts the size, location and orientation of the CAD model to correspond to the physical model you want)
  4. build the physical prototype model in layers (a machine, using one of several techniques, builds your model one layer at a time from polymers, paper, or powdered metal)
  5. clean and finish the model (remove the prototype from the printer, detach any supports, cure photosensitive materials, and sand, seal, or paint the model to improve its appearance and durability).

You can build a physical model of your invention from one of several different kinds of layers (each with its own advantages and disadvantages):

  • Liquid
    • polymer, electroset fluid, or molten material
  • Particles
    • fused by laser, or joined with a binder
  • Sheets
    • bonded with adhesive, or with light
Particular techniques used to form those layers include:
  • solidification of a resin via electromagnetic radiation
  • stereolithography
  • fused deposit modeling
  • selective laser sintering
  • 3-D printing
  • laser engineered net shaping
  • laminated object manufacturing
  • polyjet modeling

If you would like to apply rapid prototyping to your invention, consider contacting Randy Hountz of Purdue University’s Technical Assistance Program (TAP). TAP and the Department of Mechanical Engineering Technology help individuals and small companies that can’t afford a technical staff. Your first 40 hours of assistance with rapid prototyping are free. Available equipment includes the Optomec LENS 750, Zcorp Spectrum Z510, Prometal Z1, and Objet –Eden 350V.

Want to learn more? Try MIT's free OpenCourseWare Engineering Design and Rapid Prototyping.

We are most grateful to Dr. Tomovic and his students for their very interesting presentation.

Patent Drawings by Richard McVicker

Some inventions patented by our members:

Bob Brand
3,179,907 Tuning system for television receivers
3,219,933 Television tuner switching system
3,241,072 Tuning control system
3,538,466 Television tuner cast housing with integrally cast transmission lines
4,503,740 Optical cutting edge locator for a cutting apparatus
4,503,896 Dog system for veneer slicer
4,601,317 Veneer slicing system
5,511,598 Veneer-slicer with remotely controllable blade angle adjustment
5,562,137 Method and apparatus for retaining a flitch for cutting
5,590,700 Vacuum flitch table with self-cleaning vacuum valve
5,678,619 Method and apparatus for cutting veneer from a tapered flitch
5,680,887 Veneer slicer with timing belt
5,694,995 Method and apparatus for preparing a flitch for cutting
5,701,938 Method and apparatus for retaining a flitch for cutting
5,819,828 Method and apparatus for preparing a flitch for cutting
5,868,187 Method and apparatus for retaining a flitch for cutting
7,395,843 Method and apparatus for retaining a flitch for cutting
7,552,750 Method and apparatus for cutting veneer sheets from a flitch

Rick Hanson
6,240,579 Unitary pedal control of brake and fifth wheel deployment via side and end articulation with additional unitary pedal control of height of patient support
6,253,397 Deployable siderails for a wheeled carriage
6,256,812 Wheeled carriage having auxiliary wheel spaced from center of gravity of wheeled base and cam apparatus controlling deployment of auxiliary wheel and deployable side rails for the wheeled carriage
6,264,006 Brake for castered wheels
6,507,964 Surgical table
D474,446 Sterilizable battery component

Bob Humbert
4,281,368 Keyhole illuminating apparatus

Ron Jackson
4,886,110 HVAC zone control system
4,943,039 Adjustable clamp
4,987,409 Level sensor and alarm
5,132,669 Level sensor with alarm
5,381,989 Adjustable spring clamp
5,944,098 Zone control for HVAC system
6,145,752 Temperature monitoring and control system
6,322,443 Duct supported booster fan
D347,596 Audible security alarm
D376,747 Door security device

Jerry McQuinn
D689,343 Universal Nutcracker

Richard McVicker
3,261,937 Three position snap switch utilizing interference blade means
3,319,477 Timer Escapement
3,332,704 Manually propelled treadmill vehicle
4,625,616 Thumb pick
6,309,076 Light barrier, screen or reflector
D240,237 Sculpture or the like
D356,653 Yard light
8389839 Thumb pick

Bill Pangburn
5,943,831 Device for Hauling Objects

Al Robbins

3,882,960 Ride quality control for surface effects craft
3,946,689 Air dynamo pressure regulation and modulation device for surface effect ships and air cushion vehicles
6,588,702 Lighter-than-air device having a flexible usable surface

Matt Thie
4,844,446 Multiple-compartment currency stacker-sorter
4,940,162 Rolled coin dispenser
7,298,280 Lighted fluid flow indication apparatus
7,617,826 Conserver

Richard Tucker
5,833,751 Powder coating booth having smooth internal surfaces
6,840,367 Material handling and manufacturing system and method
6,976,835 Manufacturing system and process
7,018,579 Manufacturing system and process

Don Walls
D707090 Torque key lever
RE36209 Door lock apparatus

Dave Zedonis
5,637,926 Battery powered electronic assembly for wheel attachment

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