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1. 1.1 Define geartrainratioand derive itforsimple &compoundgeartrain?
1.3 Relate meritsanddemeritsof Cycloidal andInvolutegears?
1.5 Anepicyclicgeartrain,as showninFig.13.35, is composedof a fixedannularwheel A having
150 teeth. The wheel A is meshing with wheel B which drives wheel D through an idle wheel C, D
being concentric with A . The wheelsB and C are carried on an arm which revolves clockwise at 100
r.p.m.about the axisof A and D. If the wheelsBand D have 25 teethand 40 teethrespectively,find
the number of teeth on C and the speed and sense of rotation of C.
Ans:

2. 2.1 Explicate brieflythe differencesbetweensimple,compound,andepicyclicgeartrains
2.3 Two parallel shaftsare tobe connectedbyspur gearing.The approximate distance between
the shaftsis 600 mm. If one shaftruns at 120 r.p.m.and the otherat 360 r.p.m.,findthe numberof
teethoneach wheel,if the moduleis8mm. Alsodeterminethe exactdistance apartof the shafts.
Ans:
2.6 A compoundtrainconsistsof six gears.The numberof teethonthe gears are as follows:
The gears B and C are on one shaftwhile the gearsDand E are on anothershaft.The gear A drives
gear B, gearC drivesgearD andgear E drivesgearF.If the gear A transmits1.5 kW at 100 r.p.m.and
the gear trainhas an efficiencyof 80 per cent,findthe torque ongear F.

3. Ans:
Efficiency=Output/Input
Powerinput=1.5/0.8kW=2 pi Nf Tf
Tf=30.55 N-m
3.1 Discussvarioustypesof geartrains
3.3 What are the varioustypesof the torquesinan epicyclicgeartrain?
3.5 Ina revertedepicyclicgeartrain,the armA carriestwogearsB and C anda compoundgearD - E.
The gear B mesheswithgearE andthe gearC mesheswithgearD.The numberof teethongearsB, C
and D are 75, 30 and 90 respectively.Findthe speedanddirectionof gear C whengear B is fixedand
the arm A makes 100 r.p.m. clockwise.

4. Ans: