IML 332E
332E: CAM Introduction
COMPUTER AIDED MANUFACTURING
IML 332E CAD&M
LECTURE NOTES
by: H. Livatyal
Spring 2005
2005-2006
2006
ITU Dept. of ME
Gümü-suyu, ISTANBUL
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COMPUTER AIDED MANUFACTURING TOPICS
IML 332E
332E: CAM Introduction
• Numerical Control Systems (NC,CNC) and Machine Tools
• Numerical Part Programming (Manual and Automatic/CAPP)
• CAD-CAM-CNC Systems Integration
• Automation in Manufacturing and Computer Integrated
Manufacturing (CIM)
• Flexible Manufacturing Cells (FMC) and Systems (FMS)
• Sensors and Process Monitoring Systems
• Rapid Prototyping Methods
• Computer Aided Special and Nontraditional Manufacturing
Methods
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COMPUTER AIDED MANUFACTURING
IML 332E
332E: CAM Introduction
DEFINITION:
Effective utilization of computer technology in the
MANAGEMENT, CONTROL and OPERATIONS of the
manufacturing facility through either direct or indirect computer
interface with the physical and human resources of the
company (after CAMI).
Dominant Operation:
Operation:
Numerical Control (NC) part programming
Common (and narrower)
narrower) concept for CAM:
Computer assisted part programming
Logical Starting point:
point:
Manual part programming
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NUMERICAL CONTROL (NC)
IML 332E
332E: CAM Introduction
DEFINITION:
The control of operation of machine tools (M/T) (or
(or
other sheetworking
and
welding
machines)
)
by
a
sheet
machines
series of coded instructions called the program,
which consists mainly of alphanumeric characters
(nembers and letters).
letters).
Main Characteristics:
Characteristics:
Preplanned and predictable
Therefore,
Therefore, NC is a typical form of:
Programmable Automation.
Automation.
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BRIEF HISTORY OF CNC M/T
Time
Characteristic
IML 332E
332E: CAM Introduction
Description
Early Industrial
Revolution
Basic Concept
J.Jackard’
J.Jackard’s method to control textile
looms by using punched cards.
2nd World War
2D Manual Applications
Parson’
Parson’s 2-D Coordinate table
operated by two people
1947
1st modern concept
Parsons’
Parsons’ NC proposal for milling
helicopter rotor blades
1952
1st effectively functioning
version
MIT’
MIT’s first NC Milling machine
1956
1st industrial contract
USAF’
USAF’s contract for 100 NC Milling
machines to 8 co.s
co.s
•
19561956-1962
Difficult years
Big opposition against NC M/T in the
contractors of USAF
1961
1st industrial success
PointPoint-toto-point control drill pressed
1970
1st CNC
Storing the programs on a computer in
add.
add. to tapes.
tapes.
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ADVANTAGES OF NC
IML 332E
332E: CAM Introduction
• NC M/T ensure positioning accuracy and repeatibility with their
DESIGN, CONSTRUCTION and CONTROLS: Good for making many
of the same part.
part.
• Complex shaped components can be made automatically,
automatically, with high
precision and reliability.
reliability.
• Parts that require a long series of operation can be made with minimal
accumulated error.
error.
• NC M/T can operate in hostile and hazardous environments.
environments.
• Since most work is shifted to offices from the shopshop-floor,
floor, production can
be monitored by the management directly.
directly.
• NC M/T mostly are capable of conducting more than one machining
operation at a time or in a sequence without repeating the part setset-up.
up.
• Minimum idle time and increased productivity.
productivity.
• Interchangeability of work between different production plants.
plants.
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NC MACHINE MOTIONS
IML 332E
332E: CAM Introduction
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TYPES OF NC SYSTEMS
IML 332E
332E: CAM Introduction
PointPoint-toto-point control system (Numerical positioning control,
control, NPC)
NC Drill presses used in drilling precise patterns of holes.
holes.
Straight cut system
Feed rate at each
Axis is controlled
Andependently,
ndependently, one at
A time. Used in face
milling,
milling, Pocketing etc.
etc.
Contouring system (continuous path system)
system)
• Each servo motor can be controlled in varying speeds in coordination to
produce angular lines and curves.
curves.
• Some simpler systems of this type use the method of breaking down the
curved into smaller linear segments which are connected to each other in a
tiptip-toto-tail fashion.
fashion.
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4
PointPoint-toto-Point vs. Contouring Control
IML 332E
332E: CAM Introduction
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COMPUTERIZED NUMERICAL CONTROL (CNC)
IML 332E
332E: CAM Introduction
CNC was first introduced in 1970 by replacing the hardwired MCU of a conventional NC
system by a microcomputer which accomplishes all the functions of an MCU with
its software.
software.
What is new?
new?
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Feed rate control,
control, buffering,
buffering, position loop control ...
Ability to edit and store programs
Ability to produce punched (or magnetic)
magnetic) tapes,
tapes, diskettes etc.
etc.
Expanded tool offsets
Expanded control of machinemachine-sequence operations
Digitizing
Circular and more advanced (NURBS etc.)
etc.) interpolation
Parametric programming
Do loops
Roughnening to a defined shape
Subroutines
Diagnostic capability
OnOn-screen geometric programming
...
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5
CNC Machining - Lathe
IML 332E
332E: CAM Introduction
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332E: CAM Introduction
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CNC Machining - Horizontal Milling Center
IML 332E
332E: CAM Introduction
14,000 rpm spindle
with HSK-63A adapter
FANUC 16MB controller
with Makino software
1,575 in/min
(40 m/min)
feed rate
1,000 psi
through spindle coolant
22”x 22”x 22” envelope
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332E: CAM Introduction
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IML 332E
332E: CAM Introduction
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IML 332E
332E: CAM Introduction
ELEMENTS
OF NC
• Tape (Media)
Media) Reader (electromechanical,
electromechanical, electromegnetic,
electromegnetic, optical etc.)
etc.)
• Machine Control Unit (MCU, sends conrol signals to servomechanism)
servomechanism)
• Servomechanism(s)
Servomechanism(s) (amplify signals from the MCU, and send them to servomotors)
servomotors)
• Controlled element (tool,
tool, turret,
turret, M/T table:
table: the numerically controlled part of M/T)
• Feedback unit (records the achieved tool movement and send them to the MCU)
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8
Ball Screw vs. Lead Screw
IML 332E
332E: CAM Introduction
•
nn
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CNC Machining - Turning
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332E: CAM Introduction
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IML 332E
332E: CAM Introduction
CNC Machining –
Turning
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332E: CAM Introduction
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332E: CAM Introduction
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CNC Milling
Milling - Cutting Tools
IML 332E
332E: CAM Introduction
Cutting Tool
Geometry
Flat end mill
Ball-nose end
mill
Kinds of
Cutting Edge
Solid cutting
tools
Indexable
inserts
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CNC Milling and CAM: Generation of Cutting Tool Paths and
Part Programs
IML 332E
332E: CAM Introduction
UNIGRAPHICS
UNIGRAPHICS
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USE OF (CAD &) CAM TECHNOLOGY
IML 332E
332E: CAM Introduction
Machining
Milling, Turning, Drilling, Grinding, Finishing
Nontraditional
Processes
Electric Discharge (EDM: Wire & Plunge),
Electro Chemical (ECM), Water Jet, PCB &
Micro chip Manufacturing
Rapid Prototyping
SLA, SLS, FDM, LOM, SGC, Milling
Milling
Robot programming
Welding, painting, finish, hoisting and
conveying, sheet forming
Measurement &
ReRe-engineering
CMM (Computerized Measurement Mach.)
Metal Forming
Sheet blanking and bending in Punch Press,
Plasma Arc Cutting, Sheet bending in CNC
Press Brake, Spinning, etc...
Microelectronic
Devices
Microchips,
Microchips, Printed circuit boards,
boards,
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Commercial CAM Software
IML 332E
332E: CAM Introduction
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•
•
•
•
•
•
•
•
•
•
•
•
•
I-DEAS
CATIA
PROPRO-Engineer
Unigraphics
Cimatron
WorkWork-NC
Power Mill
Hyper Mill
CAM Works
Master CAM
SurfSurf-CAM
NCNC-Gibbs
AutoAuto-CAD based CAM programs
....
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CAM IN MACHINING OPERATIONS
IML 332E
332E: CAM Introduction
Basic Advantages
In mass production
• Better geometric repeatability
• Combining many operations in one machine
• Flexibility: Many different parts on one machine
• Flexibility: Quick and easy implementation of design
modifications
In production of tools, dies and molds
• Quick and hasslehassle-free production of complex 33-D
surfaces
• Drastic Time reduction in part programming
• Accurate production of the geometry developed during
the CAD stage and verified in the CAE stage
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IML 332E
332E: CAM Introduction
Realization of a
Product via
Computer Aided
Processes
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Phases in Die & Mold Production
IML 332E
332E: CAM Introduction
• Design (CAD & CAE)
• Selection of support components and design of functional components
Tool Path Generation
• Tool Path Generation (CAM)
• NC programs are needed for machining of EDM electrodes or for direct
machining of functional components
• Machining (CAM)
• Typical processes: electro-discharge machining and CNC machining
(turning and/or milling)
• Benching
• The tooling is assembled
• Critical dimensions are checked: Coordinate Measuring Machine (CMM)
• Hand finishing: Grinding and polishing.
• Tryout
• During tryout, a limited number of parts are produced with the die or mold
• Minor changes on the tooling may be necessary for required performance
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Die & Mold Components
IML 332E
332E: CAM Introduction
• Functional Components
– Die
– Punch
– Blank holder
– Cavity inserts
– Ejector pins
– etc.
• Support Components
– Guide pins and bushings
– Holding plates
– etc.
ERC/NSM
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Milling of Sculptured Surface
IML 332E
332E: CAM Introduction
CAMAX
FIDIA
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Die & Mold Production Information Flow
IML 332E
332E: CAM Introduction
Digitized Part
Data
Prototypes / Models
Part File
Part Drawing
Part Design for
Manufacturing
Data for CMM
Process Modelling
and
Structural Analysis
Die / Mold
Initial Design
N
Die / Mold
Design
Satisfactory ?
a
Y
b
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IML 332E
332E: CAM Introduction
Satisfactory Design
Die / Mold
Detail Design
Data for CMM
Data for CMM
CNC Machining
Cavities / Cores
c
b
CNC Machining
EDM Electrodes
EDM Electrodes
Inspection
EDM
Cavities / Cores
Polishing
( Manual, Mechanical, Electro-Chemical )
d
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IML 332E
332E: CAM Introduction
c
d
a
Polished Cavities / Cores
Data for CMM
Cavities / Cores
Inspection
Data for CMM
Die / Mold
Assembly
Die / Mold
Try out
Try out
Parts Inspection
Inspected Parts
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Business Card Holder - Design Phase
IML 332E
332E: CAM Introduction
Part Design
ERC/NSM
Process Simulation
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Die & Mold Production –
Design Phase
IML 332E
332E: CAM Introduction
Fused Deposition Modeling
(FDM)
Principle
Filament
Heated
FDM Head
Example
Molten
Filament
Supply
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Business Card Holder -Design Phase
IML 332E
332E: CAM Introduction
Glass
Window
Logo
Insert
Cavity
Plate
Ejector
Plate
Gas Nozzle
Support
Mold
Base
PRO-E
ERC/NSM
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Business Card Holder Machining Phase
IML 332E
332E: CAM Introduction
ERC/NSM
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Business Card Holder -Tryout Phase
IML 332E
332E: CAM Introduction
ERC/NSM
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Business Card Holder Tryout Phase
IML 332E
332E: CAM Introduction
ERC/NSM
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