Tutorial: Engineering technology Topic: Transmission by gear wheels Prepared by: Ing. Jaroslav Hábl Projekt Anglicky v odborných předmětech, CZ.1.07/1.3.09/ je spolufinancován Evropským sociálním fondem a státním rozpočtem České republiky.
TRANSMISSON BY GEARS WHEELS Is the gear with constant gear ratio (without slippage). It is used for small axis distances. Gear is accurate with high efficiency. Production of wheels is expensive.
GEAR RATIO TRANSMISSON BY GEARS WHEELS
Types of gears according to teeth shape a) direct b) obliquec) herring bone gear ( double oblique) TRANSMISSON BY GEARS WHEELS
Types of gears according to teeth shape bent bolt spiral cylindrical TRANSMISSON BY GEARS WHEELS
Types of gear trains Gear train with Gear train with Gear train with parallel axis axis going to various skew axis sides TRANSMISSON BY GEARS WHEELS
Involute gear tooth formation r – pitch linen – generatrix b1 – base circle e - involute TRANSMISSON BY GEARS WHEELS
Basic tooth profile p – teeth pitch s –teeth thickness e – teeth gap width r – pitch line m – module ha – tooth head height hf – tooth heel height c – clearance TRANSMISSON BY GEARS WHEELS
SIZES OF TOOTHING AS THE MODULE FUNCTION Tooth head heightha = m Tooth heel height hf = m + c Tooth heighth = ha + hf = 2,25 m Pitch line diameter d1 = z. m Addendum circle diameterda = d + 2ha = d + 2 m Heel circle diameterdf = d – 2hf = d – 2,5 m TRANSMISSON BY GEARS WHEELS
Stroje a zařízení I, J. Doleček, P. Gajdoš, V. Novák Strojnictví I, J. Doleček, Z. Holoubek Strojnictví II, J. Doleček, Z. Holoubek Moderní strojírenství, Josef Dilinger a kolektiv
Write down the formula for the calculation of gear ratio. Name at least 3 types of toothed gear trains. Draw bearing with oblique contact.