Question

In the gear train shown below, the pinion 2 is the driver, and gear 5 is the output gear. All gears are spur gears has a module of 2.5mm and pressure angle of 200. The number of gear teeth are: N2 - 14, N3 - 84, N4 - 14, N5 - 70 teeth. The gear set transmits the power of 1.5KW at a constant angular velocity of XX rev/min. Where XX is the last two digits of your University ID number. Example: if your ID is 36140157. XX will be - 57 rpm. The transmission efficiency of each gear pair is 98%. Answer all the following questions For this gear train, answer the following questions (Determine the center distance between the axes of the gears. (6 Marks.1 (Determine the angular velocity and torque on pinion 2 and the output gear 5. (12 Marks 2 (Determine the reaction forces on the bearings of gear 5. (12 Marks 3

Answer 1

given, input, こ 1.5kw spur gear. module = 2.5mm Power speedin, 570pm (assume/ put your I.P.) N2 = 14, N₃= 84, = 84, N4 = 14 Ns=70 feeths, gear drive N3 2 now, 2Tlxspeed 21x57 60 = 5.97 rad's win = 60 beth 122.5 mm - beth B'C = 2 © To find the centre distance gear 2&3 = = AB = mx N2 + N3 AB 2.5x14 + 2.5x84 2 gear 485 = B'c MXN4+ m Ng 2.5x14 +2.5x70 2 B'c = 105 mm for angular velocity of torque cet at gear 2. W2= winp = 5.97 rad's Power 1.5816 T2 = 5.97 3 = 251.25 Nm ا را 2

gear of drives is 98% at nor efficiency gear n = » Pout = Pout Pin Pinx n = 0.98x1.5 A Pout = 1.47 kW. find gear 5. now. to angular velocity of Ws Na Ns Nz 14 zes wg wax 84 ws = 5.97 x = 0.19g rad/s. 30 now to find torque Pout Ts = 1.47x103 = 7386.93 km كلها 0.199 To find reaction force at 75=radius of gear 5 Ts Ts = fxr5 = F = 85 2.5x70 r5 = = 87.5mm 2 738 6.93 F= 84.422 IN 0.0875 F = 84.422 IN