By Abhishek Tevatia Assistant Professor, Maharaja Agrasen Institute of Technology, Rohini, Sec-22, Delhi – 110086
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Computer Aided Manufacturing (ETME-401)
Second Term
Abhishek Tevatia, Assistant Professor, MAE, MAIT, Delhi
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Computer Aided Manufacturing (ETME-401)
Topics to be covered
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Block diagrams of CNC operations. Nomenclature, types and features of CNC machine tools. Elements of CNC machines and systems. Machine control unit, Position control significance. Open loop and closed loop systems. and its
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Engineering analysis of NC positioning systems. Precision in NC positioning systems: resolution, accuracy and repeatability. control
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Actuators: DC servomotor, ac servomotor, stepper motor. Transducers and feedback elements: resolvers, inductosyns optical grating and encoders
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Abhishek Tevatia, Assistant Professor, MAE, MAIT, Delhi
Computer Aided Manufacturing (ETME-401)
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Modern CNC machines: CNC lathes. Turning centres. Machining centres. Automatic pallet changers. Automatic tool changers.
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Direct numerical control and applications.
CNC machine design features. Supporting structures. Guide ways. Ball screw-and-nut mechanisms. Machine spindles. Concept of rigidity and relation with accuracy.
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Computer aided programming: APT Part Programming. APT Part Programming cont…
Abhishek Tevatia, Assistant Professor, MAE, MAIT, Delhi
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Computer Aided Manufacturing (ETME-401)
Lecture - 19
Block diagrams of CNC operations. Nomenclature, types and features of CNC machine tools.
Abhishek Tevatia, Assistant Professor, MAE, MAIT, Delhi
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Computer Aided Manufacturing (ETME-401)
Computer Numerical Control (CNC): It is a self-contained NC system for a single machine tool uses a dedicated mini computer, controlled by the instructions stored in its memory, to perform all the basic numerical control