Chapter 8, Problem 14P

A compound shaft drives three gears. Segments (1) and (2) of the compound shaft are hollow aluminum [G=2860 ksi] tubes, which have an outside diameter of 2.75 in. and a wall thickness of 0.28 in. Segments (3) and (4) are solid 2.14-in.-diameter steel [G= 8000 ksi] shafts. Assume that L₁-60 in., L₂=4 in., L3=13 in., L4-12 in, Tg-36 kip-in., Tp-45 kip-in., and Te-17 kip-in. The bearings shown allow the shaft to turn freely. (a) Determine the maximum magnitude of the shear stress max in the compound shaft. (b) Determine the rotation angle (c) Determine the rotation angle of flange C with respect to flange A. of gear E with respect to flange A. Answers: (a) Tmax (b) CIA (C) ΦΕΙΛ = = e 5 11.48 i -2.197 = i -2.74 B TB L2 (3) ksi. Tp TE ᾽Ε

Figure shown below illustrates the gears in a speed-change gearbox used in machine tool applications. By sliding the cluster gears on shafts Band C, nine speed changes can be obtained as shown in Table given below. The problem of the machine tool designer is to select tooth numbers for the various gears (2 to 10) so as to produce a reasonable distribution of speeds for the output shaft. The gears 2, 6 and 9 are having 20, 25 and 50 teeth respectively. The input shaft speed is 450 rpm and the output speed can vary from 137 rpm to 580 rpm depending on the sequence of the gears. If the output speed obtained through the gear sequence 2-5-5-8 is 257 rpm and if the minimum and maximum number of teeth in the gear system are 20 and 50 respectively, (i) Suitable tooth numbers for the remaining gears (3,4,5,7,8 & 10)

Abanoub Gendy-gear_ret o_wcrksheet.pdf Gear Ratio Worksheet Directions: Find the gear ratio of each pair of gears. Make sure to pay attention to the driver and follower. The arrow points to the driver. Simplify all ratios and show all work. 1. 8 32 GR = 6. 40 64 GR =

A bicycle's gear ratio is the number of times the freewheel turns for every one turn of the chainwheel (see figure).   The back half of a bicycle is given. A line labeled "Freewheel" is pointing at the center of the rear wheel. A line labeled "Chainwheel" is pointing to the center piece connecting the two pedals. The table shows the numbers of teeth in the freewheel and the chainwheel for the first five gears of an 18-speed touring bicycle. The chainwheel completes one rotation for each gear. GearNumber Number ofTeeth inFreewheel Number ofTeeth inChainwheel 1 32 24 2 26 24 3 22 24 4 32 40 5 19 24 Find the angle through which the freewheel turns for each gear. Give your answers in both degrees and radians. (Round your answers to one decimal place.) gear 1 =   rad=   gear 2=    ° rad=   gear 3=     °  rad=   gear 4=    ° rad=   gear 5=    ° rad=

The following gear wheels are available to form a gear train. Design a compound gear train to obtain minimum velocity ratio using five shafts, where driver and driven shaft axes should be parallel to each other. Sketch the arrangement and also list down the conditions used to get minimum velocity ratio. Gear Туре Spur Module (mm) No. of teeth A 90 B Bevel 80 Spur 80 D Bevel 4 24 E Spur Bevel 20 F 4 30 Helical 3 76 H Bevel 4 70 Helical 3 30 J Helical 3 24 K Spur 100 Helical 70 23

For a pair of spur gears, one design decision is to specify the pressure angles. Please select the common values of pressure angle per textbook.           300     200     250

You design a gearbox with a gear ratio of 5 (GR=5=TGB/Tm) to pull a load (FL) of 76 lbf using a motor and winch (rw=0.25 inches). What is the torque experienced by your motor when pulling the mass up at a constant speed in lbf ft? Note the units

The teeth of the gear arrangement have Gear A=40teeth, Gear B=70 teeth and Gear C= 50teeth, a pinion (driver Gear) that rotates at 625 rpm, and idler Gear B and a driven gear (Gear C). The gears have a module of 5mm and a pressure angle of 200. Find the pitch diameter of gear C in mm.

The figure below shows the power transmitted through a gear drive to multiple output shafts. Gear A is mounted on an electric motor with a rotational speed of 600rpm. Gear A drives a simple gear train consisting in gears B, C, D, and E and transfers the input power to each gear to the shaft on which is mounted. The power delivered from shafts B, C, D, and E are: 8hp, 12hp, 5hp, and 5hp, respectively. For simplicity, all gears have a diametral pitch of 3 and the following numbers of teeth: NA=75, NB=15, NC=120, ND=15, NE=36.   The torque on shaft D is most likely:     2015 lb in     105 lb in     250 lb in     630 lb in