Belt Drives Lecture-1(a) PDF

Lecture-1(a) Belt Drives ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS  COURSE OUTCOMES ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS  CONTENT 1.1...

Lecture-1(a) Belt Drives ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS  COURSE OUTCOMES ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS  CONTENT 1.1 Introduction 1.2 Types of Belts 1.3 Flat and Rounded Belt Drives 1.4 Summary ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS  Introduction ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS  Application Examples Source: http://www.practicalmachinist.com/vb/antique-machinery-history/source-replacement-flat-belt-167449/index2.html ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS  Mechanical Drives Flexible Drive Rigid drive - belts, chains, - gears, shafts, and ropes splines Flexible drives transmit power over long distances. The intermediate link absorbs shock and vibration. Flexible drives are less costly as compared to gear drives. Flexible drives provide considerable flexibility in terms of locating driving and driven shaft. Limitation: Flexible drives occupy more space. Not so high velocity ratio and the velocity may not be constant. ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS  Advantages of Flexible Drives: ❑ Transmits power over long distances. ❑ Absorbs shock and damps vibration. ❑ Flexibility in the location of shafts. ❑ Less costly as compared to gear drives, and ❑ Low maintenance cost. ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS  Types of Belts ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS Types of Belts Main characteristics : – Applicable for long center distances, – angular-velocity ratio between the driving and driven shafts is neither constant nor exactly equal to the ratio of the pulley diameters, – idler or tension pulley can be used to avoid adjustments in center distances. ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS Flat-belt Geometry: (a) Open belt (b) Crossed belt ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS Types of drives: Non-reversing Reversing Reversing & Open Belt ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS Flat-belt Geometry: Variable Speed Quarter Twist Belt Drive Fork Belt Drive Controlled ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS  Flat and Rounded Belt Drives ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS Flat Belt Drives Efficiency of flat-belt drive: about 98%, Efficiency of a V-belt drive: ranges from about 70 to 96%. Length of the belt: ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS Flat Belt Drives (cont.) Angle of wrap: Length of the belt: ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS  Thank You! ©2021 Mechanical Engineering Design, MEB3023 Universiti Teknologi PETRONAS