CONTENTS Pel Ie 2, CNC INTRODUCTION 3. ELEMENTS OF CNC 4, BLOCK DIAGRAM OF CNC abide). en VE (Gal IN a 6: HOW CNC WORKS? 7, FEATURES OF CNC MACHINES. 8. CNC PROGRAMMING BASICS 9. COMMON FORMAT OF A BLOCK 10. PROGRAMMING KEY LETTERS. 11, ADVANTAGES 12. CHALLENGES 13. CONCLUSION 14. REFERENCESHISTORY BU aiiere eMule ee aa Lec Oo Tee Prof. John T Parson. eet Care at coe ac eel Lael ecg around 1980. Modern CNC Machine are improving further as the technology meee Mee Eis mel Meas ace tele] gel Layo) PrietaesENC INTRODUCTION A numerical control system in which the data handling, control sequences, and response to input is determined by an on-board computer cela emne lalla) tool.TYPES OF CNC MACHINE. Coe Spring forming. er Xo1 OU aimee lon aoe rluiemeviadialsManr (ounce Electric Discharge Machine. Due) ccge ca Welding. CNC Punch Press.ELEMENTS OF CNC MACHINE + ACNC machine consist of following 6 major elements: iis ia v win input Device Drone eat Etat Cr DMT sre) ero De NatsData | Control Processing! Loop Unit | Unit Motion Data Miscellaneous Function Driving SystemOPEN LOOP AND CLOSED LOOP CONTROLS Work table Position Feedback signal sensor In open loop systems the slide may overshoot or may not reach desired Paes Me cme nh ccUCht hiatal hMachttacied ct! machining. Tikelortete Melo) Meum M sled (oleae lee Lele co Meola stars i(e od Tea me eet eo LolaHOW CNC WORKS Controlled by Gand M codes. aes eM Lan cl eee Lgl needa oe PETA MAN leleimed mele Mie tssi-tal-Te coe Mella aCe] Lmtell e-em aires Mee acne es tke cil G & M codes are automatically generated by the computer software.FEATURES OF CNC MACHINERY Me eMC uC le eeu rel eee ic Meee cos PETA RCC alee eal ee ROU elie eke siete Movement is controlled by motors (actuators). zero MMe seh eure ea ec le a-1)) Tool magazines are used to change tools automatically.CNC PROGRAMMING BASICS + CNCinstructions are called part program commands. * When running, a part program is interpreted one command line at a time until all lines are completed. * Commands, which are also referred to as blocks, are made up of words which each begin with a letter address and end with a numerical value.CNC PROGRAMMING é Programming consists of a series rela Tele: UL ar EUR Ue sda + Coordinate System des Ie ol aes oo ee enema ee) basen establishing operating conditions SO Rue el se IN codes- specify program line number atl to executed by the MCU * Coordinates: X,¥,Z, RX,RY,RZ PN ica ele eed BOS efe hoes) lala Mure Roum cacao 4 Boe Arlt adel) * Feed rate and spindle speed *Feed and Speed Codes: Fand S G eae blte (eel tr Hey °Li Ma eels B Byler Reel ate (eet tte} is) *Tool codes: T — specify tool number * Tool Control: Tool and tool PVT es *Miscellaneous codes — M codes rol mt solo) -luleslgl cele ue Relaal-UarLeleh Lao)COMMON FORMAT OF A BLOCK i=l Wl ile sy Dimension bate i A rele LCle Individual WordsPROGRAMMING KEY LETTERS 0 - Program number (Used for program identification) * N-Sequence number (Used for line identification) * G- Preparatory function Cee Seco e car seg) Y-Y axis designation Z-Zaxis designation eet emer uray F—Feed rate designation §- Spindle speed designation + H-Tool length offset designation + D-Tool radius offset designation * T- Tool Designation Mma icsc ic loltemit is ra toleAdvantages of CNC Baers e at Cle aerate cc ee Bcetear CRC tc) iv. - Avoids human errors v. -CNC machines are safe to operate SiMeR eur) halo Ua BEM islets be ae VERT lel R ogo} ATP OL IL Na-Ca Leie cceeeestace) (cea UTS Cea SeyCHALLENGES i. . COSTLY SETUP, SKILLED OPERATORS. poe SC] elisa eel TUM UN cds e\u eae] o) REQUIRED. ili. MAINTENANCE IS DIFFICULT.CONCLUSION + The advantage of a CNC system are that the operation of a conventional machine is removed and the part production is CELA Tiel vay Pee eee ater eC hee a ei ae Reet gece Pa ame eee reece ee emurnmctt ry Reece C lee mle che) a Cle sete] aa RUoiameLi tel Pen amen ae int een etn eeu a CNC machines have their wide scope because they are easy to LET Rae ela eel oe hae B oleae Relea diag) Pu sateliil hdd elTHANK YOU