Automatic orientation circuit indicator device for portable power tools and the like

摘要

A gravity-activated, electric switch rigidly mountable on any type of tool which is to be used in a precisely accurate position respective to a horizontal or vertical plane includes a sealed cylindrical case having an electric contact at each end, a spherical steel ball activated by gravity to freely roll inside the case for making electrical connection between the contacts, the contacts being located so that the gravity-activated ball makes connection therebetween only when the tool is in a precisely accurate position respective to a horizontal or vertical plane.