Design of a bench saw cutting machine for wood with automatic braking system

Abstract

This research paper explores the design of an automatic safety brake mechanism on a manual circular table saw machine which stops the blade from rotating when human flesh is detected in the blade proximity. Fatal injuries are occurring, human thumbs and entire hand cutting during operation when operator accidentally touches the spinning blade. It has become a matter of concern to develop the safety mechanism which can be retrofitted on old-model table saw machines used to train students at a university wood workshop. The researchers made use of capacitive proximity sensors to detect human flesh and then automatically activate the brake pawl to the rotating blade, D.C injection brake voltage which abruptly stop the running motor. The design procedure confirmed the quick release of the safety mechanism within 0.25 seconds as revealed from the simulation of circuits in Proteus software. With this design it is possible to stop the spinning blade in 0.25 seconds, before the operator touches the spinning blade and also the mechanism is adoptable to all circular saw machines (panel saw, bench saws), thus making a work-safe environment on the circular saws.