Problem:
The step-cone pulley is to be designed for transmitting a power of at least 0.75 hp. The speed of the input shaft is 350 rpm and the output speed requirements are 750, 450, 250 and 150 rpm for a fixed center distance of ‘a' between the input and output shafts. The tension on the tight side of the belt is to be kept more than twice that on the slack side. The thickness of the belt is ‘t' and the coefficient of friction between the belt and the pulley is μ.
(1) Formulate the problem of finding the widths and diameters of the steps for minimum weight. (1hp=745.7W). For some parameters not given, you can assume some realistic values.
(2) Design widths and diameters to minimise the weight (use at least two different optimisation techniques/software to find the solution and compare the results)
(3) Discuss the effects of the design variables on the weight of the step-cone pulley.
(4) Prepare a report which provides detailed design information. Design guideline should also be included in the report (assuming your colleagues will use this guideline in their designs of this type of pulley)
