Patent ID: 8827278
Filing Date: 2014-09-09
Classification: B24B,B25F,Y10T

Abstract:
1. An adaptor for adapting a working element to an end of a power tool shaft, comprising: a central hole passing through the adaptor and having a longitudinal axis; a driving end facing the end of the shaft, the driving end comprising a planar driving surface having a perimeter; and a tool end facing the working element and having a protruding portion; wherein the driving surface of the driving end is provided with grooves and bosses alternately arranged around a circumference of the driving end, wherein each of the bosses has a first side face extending perpendicular from the driving surface facing the central hole and located on a plane passing through an edge of a regular polygon positioning hole defined by the first side faces of each of the bosses, a second side face extending perpendicular from the driving surface and extending radially along the entire length from the positioning hole to the perimeter of the driving surface, and a third side face extending perpendicular from the driving surface and extending radially along the entire length from the positioning hole to the perimeter of the driving surface, wherein the grooves are defined by the second and third side faces of adjacent bosses and a lower surface, and the lower surface of the grooves are coplanar with the driving surface such that the grooves extend radially the entire length from the positioning hole to the perimeter of the driving surface.