325-lec-8-flex drives (annotated)

325-lec-8-flex drives (annotated) - MECH 325 Flexible Drive...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
MECH 325 Flexible Drive Elements MECH 325 2 Objectives By the end of this section, you should be able to: Describe the characteristics and uses of: Flat belts V-belts Timing belts Roller chains Analyze flexible drives in terms of power, speed, forces, and life Select and size an appropriate flexible drive for a given application MECH 325 3 Belt Drive Overview Advantages Potential failure modes MECH 325 4 Belt Kinematics
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
MECH 325 5 Flexible Drive Configurations Non-reversing Open Reversing Cross Belt Driver Reversing Open Belt Driver Driver MECH 325 6 Flexible Drive Configurations (cont’d) Twisted Belt Drive Idler Pulley (Rotates Free on Shaft) Clutch-less disconnect Driver Driven (Keyed to Shaft) MECH 325 7 Flexible Drive Configurations (cont’d) Continuously Variable MECH 325 8 Belt Power Transmission Transmission Parameters Pulley FBD
Background image of page 2
MECH 325 9 Flat Belt Tensile Forces Identify A-F on the chart Identify: Slack-side tension Taut-side tension Centrifugal tension Pretension MECH 325 10 Belt Tensions 2 1 f ci f e FF e 2 1 f e MECH 325 11 Flat Belt Equations Forces Torque Power 1 2 f c c e  12 2 d TF F  33,000 FFV H 1 1 f i f e d e 2 32.17 60 c wV F    MECH 325 12 Belt Design Considerations H a = K 1 K 2 H tab H tab H a K 1 wrap angle correction (V-belts only) K 2 belt length correction (V-belts only) H d = H nom K s n d H nom H d K s service factor (next slide) n d design safety factor Want
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
MECH 325 13 Belt Service Factors (K s ) Driven Equipment Operating Period /day < 8 h < 16 h > 16 h < 8 h < 16 h >16 h Driving Machine: Driving Machine: Reasonable Smooth Coarse Starting torque 100-200% FL Starting torque 200-400% DC motor (shunt wound), AC motor (star-delta), IC engines 8+ Cyl., Turbines DC motor (series / mixed excitation), AC motors, 2 stroke engines, IC engine <8 Cyl. or under 600 rpm Smooth Machine Tools including lathes, drills, etc.
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 10

325-lec-8-flex drives (annotated) - MECH 325 Flexible Drive...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online