ABSTRACT
Would you approve a motor mount as illustrated in Figure 1 (a) for clutching and declutching? The mass of the motor is 18.6 kg and the center of the motor shaft is 12 cm above the bottom of the motor’s base, which is 17.8 cm wide. Center-to-center distance between the shaft of the motor and the shaft of the driven machine is to be 50 cm. Belt tension is to be 298.5 N, the belt should be replaced after the center distance increases 2.4 cm, the angle of the line between centers may be from 15° to 20° with the horizontal, and the shaft of the driven machine is above and to the right of the motor shaft. The gravitational force on the motor is given by W=mg in terms of the mass of the motor and the acceleration of gravity. Thus
to give T/W=1.637. From the motor specifications, b=12 cm and a must be equal to or larger than 17.8/2=8.9 cm. As an aid to selecting a value for a, plot T/W as a function of ξ for =20° and 30° and for θ=20° and 30°, as shown in Figure 14. Select =20° and compare designs using θ=20° and θ = 30°. Use of =15° was rejected in order to avoid excessive belt tension as the belt stretches. Consider ξ=0.2 to have a larger T/W ratio and consider ξ = 0.685, corresponding to a=13 cm, to get a more compact mounting. Thus a=44.5 mm for ξ=0.2 and 13 mm for ξ=0.685.
