Design, development and testing of an orthogonal shaft transmission lawn mowing machine

摘要

A lawn mowing machine with an orthogonally powered transmission system from a5.5 HP engine via a bevel gearing to a moulded tool steel cutter blade was designed,developed and tested. A 5.5 HP internal combustion engine serves as the powersource, transmitting power horizontally through a vee belt to a pair of meshing bevelgears that transmitted the power orthogonally to the cutter blade. The cutter blade wasmoulded from 3mm thick tool steel cutting tools. A structural frame built from 25 x 25mm structural angle iron and supported on a large rear wheel of 350 mm diameter andfrontage wheel of 150 mm was used to enhance smooth movement on rugged terrains.An adjustable height push – behind handle that allows for easy directional change wasused. Tests carried out on a lawn of average weed height 800mm showed a cuttingrate of 3.16 m2/min. while operating at an average operator pace as against1.77m2/min. when manually cut, indicating a 78.53% productivity increase. Maximumobserved vibration level on push handle was 152.4 and 71.7 mm/sec. under cuttingtool attachment and detachment respectively. Maximum noise levels with cutting toolattachment and detachment was 94.1 and 77.36 dB respectively.