&lt;p&gt;The recent advancement in air assisted spraying is air sleeve boom sprayer in which the air jet developed at each nozzle along the boom assists spraying and brings the major improvements in the spraying overcoming many of the difficulties experienced in conventional spraying. The air discharge is developed by an axial blower and fed through the sleeve. The existing model of air sleeve boom sprayer available at ASPEE research and foundation, Mumbai is equipped with hydraulic transmission system, which is very heavy and costly. A project was therefore undertaken to design and develop a mechanical transmission system in place of hydraulic transmission.&lt;br /&gt;
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Initially, the existing air sleeve boom sprayer was tested and its overall efficiency was found. Based on the test results of the existing boom sprayer, the speed ratio was taken as 4:3 and power to be transmitted as 25 hp. The gear and pinion of the mechanical transmission were designed by taking peripheral speed as 6.5 m/s. The shafts were designed by taking bending moment and tangential loads. A suitable casing was designed by taking minimum clearance of gear and pinion from casing wall. The designed gearbox was fabricated at ARDF, Mumbai. The hydraulic transmission system was replaced by the designed gearbox and the performance of the air sleeve boom sprayer was evaluated in the controlled wind tunnel conditions.&lt;br /&gt;
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The test results showed that the overall efficiency of mechanical transmission system was 39.5 to 61.6 per cent higher than that of hydraulic transmission system. The higher efficiency of the system will help in transmitting more power to the blower. The designed gearbox is lighter in weight and cheaper than the hydraulic transmission system. Based on these results, it is future to use mechanical transmission system in place of hydraulic transmission in the air sleeve boom sprayer to provide economical spraying operation.&lt;/p&gt;
