1 / 10

Introduction To CNC

Introduction To CNC. Compute Integrated Project Lead The Way. NC/CNC. History of NC Definitions Advantages of CNC Disadvantages of CNC Resources. History Of Machine Tools. Single items produced by craftspeople Eli Whitney (Cotton Gin) - Interchangeable Parts

hortonc
Download Presentation

Introduction To CNC

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Introduction To CNC Compute Integrated Project Lead The Way

  2. NC/CNC • History of NC • Definitions • Advantages of CNC • Disadvantages of CNC • Resources

  3. History Of Machine Tools • Single items produced by craftspeople • Eli Whitney (Cotton Gin) - Interchangeable Parts • Engineer designed parts for production (tolerances). • WW II - development of servo motors (electrically aimed guns) • Servo motors applied to machine tools

  4. History • Development of G codes - Punch tape input (Cartesian Coordinate System) • 1970’s Development of computer chips • Cheaper processing power • Smaller computers • More reliable

  5. Definitions • NC - A method of accurately controlling the operation of a machine tool by a series of coded instructions, consisting of numbers, letters of the alphabet, and symbols that the machine control unit can understand • MCU - Machine Control Unit - decodes NC codes to drive and monitor servo motor movements.

  6. Definition • CNC - Computer Numeric Control - computer provides machine codes to the MCU. • Control Systems • Open loop system - servo motor driven by pulses without feed back encoders. • Closed loop system - servo motor is driven by electrical pulses. An encoder provides feedback to verify machine movements.

  7. Advantages Of CNC • Increased productivity after programming is completed • Reliability - reduces human error • Often eliminates need for special jigs and fixtures • Reduces location of part features • Makes possible the machining of complex shapes requiring simultaneous 3 axis motion

  8. Advantages • Single part and production runs can be programmed and machined with minimum effort and cost. • Programs can readily be altered and re-run • Reduced inspection costs (more reliable) • Once programming, setup and verified the equipment can be operated by a less skilled operator.

  9. Disadvantages • Initial cost of CNC machine tools • Servicing of equipment • Larger machines require more space • Personnel must be trained in the programming and operation of this equipment.

  10. Resources • Fitzpatrick, Mike, Computer Numerical Control Simplified, 1989 Glenco Publishing Company. ISBN 0-02-676410-5 • Powers, John Jr., Computer Automated Manufacturing, 1987 McGraw-Hill Book Company. ISBN 0-07-050601-9 • Groover, Mikell P. and Zimmers, Emory W., CAD/CAM, Computer Aided Design and Manufacturing, 1984 Prentice -Hall Inc. ISBN 0-13-110130-7 • Luggen, William W., Fundamentals of Computer Numeric Control, Third Edition, 1988 Delmar Publishers. ISBN 0-8273-6496-2 • CNC Workshop (CD-Rom), Torcomp Publisher. Cost $39.95 – Contact TorComp at 888-561-7521

More Related