Answer Happy

6 Problem 3. Transmission of rotational motion A schematic diagram of winch drive is shown in Figure. Notation is taken as follows: 1, 2, 3, 4, 5 -gear-wheels or worm gear-wheels, which numbers of teeth are accordingly equal to zi, 22, 23, 24, 25; worm with 2. threads; 7,8 belt pulleys with diameters dy, ds: 9 electric motor with power Prand nominal rotational speed nc 10 shaft, on which winch pulley with diameter d, is installed (pulley is not shown in Figure). It is assumed that all gear transmissions and worm gearings are placed inside closed boxes (gear boxes). Slippage (sliding) in belt transmission has not to be taken into account. Parameters of winch drive are given in Table 1. But average values of efficiency coefficients n for transmissions and support bearings can be taken from Table 2. And it is necessary to take into account that rolling bearings are installed in all supports. To determine the weight Q of a body, which can be uniformly winched without overloading of electric motor. Variant from the Table 1 is taken in accordance with the penultimate figure of student code, but drawing - in accordance with the last figure of student code. Table 1
Efficiency coefficient n 0,97 ... 0,98 0,96 ... 0,97 Transmission or unit of winch drive Box gear transmission: cylindrical wheels bevel wheels Box worm gearing: one-thread worm two-thread worm four-thread worm Belt transmission: with flat-belt with V-belt One pair of rolling bearings Winch pulley 0,70 ... 0,75 0,80 ... 0,85 0,85 ... 0,95 0,96 ... 0,98 0,95... 0,97 0,990 ... 0,995 0,96 ... 0,98
dp Z 15 16 NN Variants 0 1 2 3 4 5 18 22 48 46 44 48 40 38 Z 29 28 27 24 25 24 23 22 21 20 Zs 95 90 80 70 75 70 Z4 50 52 54 52 58 60 02 64 66 68 20 19 20 SIIS 2 4 1 2 4 + 2 4 1 dz mm 50 56 63 71 80 90 700 112 125 140 120 150 180 200 220 250 dx mm 80 100 125 160 180 224 200 250 224 200 P kW 2,2 3,0 4,0 6,0 7,5 10 Table 1 ne apgr/min 710 955 1440 720 9.55 1440 710 970 1450 735 7 8 9 22 23 24 34 32 30 60 55 50 300 320 350 17 22 30
만 6 9 7 8 co 10 1 Fig. 4