Unformatted text preview: MECH323 – 2007 GEARS____________________________ Fundamental Concepts for Gears References: t Shigley’s Mechanical Engineering Design (8 h Ed. Budynas and Nisbett) [Chapters 13, 14 and 15] th Fundamentals o f Machine Co mponent Design (4 Ed. Juvinall and Marshek) [Chapters 16 and 16] Gear o Toot hed member t ransmit s rot ary mo t io n fro m o ne shaft to anot her o Mo st rugged and durable mechanical po wer t ransmissio n element o Co st increase w it h precisio n, usually mo re co st ly t han belt s and chains Spur Gear o S imp lest and mo st co mmo n t ype o f gear o Teet h are parallel t o axis o f rot at io n o Transmit t ing mo t io n/t o rque between t wo parallel shaft s o Hig h efficient Helical Gear o Teet h are inclined to t he rot at io n axis o Can t ransmit mo t io n/t orque between parallel and no nparallel (cro ssed) shaft s o The same handed helical ang le fo r cro ssed arrangement , and o ppo sit e helical ang le fo r parallel arrangement o Gradual t eet h engagement reduces no ise a nd increases capabilit y o f lo ad carr ying o Inclined t eet h int ro duce t hrust lo ads and bend ing co uples o n t he shaft o Less efficient t han spur gear generally Bevel Gear o Teet h are fo rmed o n conical sur faces o Transmit s mo t io n/t o rque between int ersect ing shaft s o General t ypes: st raig ht , spiral, zero l, hypo id and sp iro id Worm and Worm Gear o S imilar t o cro ssed arranged helical gear set, but t he helical ang le ( lead ang le f...
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- Fall '09
- gear, po int, pitch diameter, ang le, Pitch circle Pitch