Patent ID: 9102047
Filing Date: 2015-08-11
Classification: B25F,Y10T

Abstract:
1. An adjustable length adaptor coupled to a turning tool which is formed of a built-in driving motor hi its interior and from which a rotary shaft rotating during a driving of the driving motor is protrude from its one side, comprising: a body part which has, at its one side, a through hole allowing a rotary shaft of the turning tool to pass through, and further has an engaging member coupled to one side of the turning tool and a support member formed at the other side of the engaging member; a varying part which has one side withdrawably coupled to the support member, with a rotary shaft to which an exchangeable work member is coupled, being formed at its other side; a driving pulley which is disposed on a top of the body part and is coupled to the rotary shaft of the turning tool; a driven pulley which is coupled to the rotary shaft of the varying part; and a belt which is connected between the driving pulley and the driven pulley and rotates the driven pulley during the rotation of the rotary shaft protruded from the turning tool, wherein either the driving pulley or the driven pulley comprises: a circular plate-shaped hub which is coupled to the rotary shaft of the driving pulley or the rotary shaft of the driven pulley and has an engaging shaft at its upper surface; a first belt contact member which is coupled to an upper surface of the hub at an interval; a second belt contact member which is installed at an interval from the engaging shaft and is slidably disposed between the engaging shaft and the first belt contact member; an elastic member which is engaged between the second belt contact member and the hub; a ring shaped cover member which is coupled to an upper side of the first belt contact member; and a tensional force adjusting member which is coupled to the engaging shaft and pressurizes the second belt contact member, so the interval between the engaging shaft and the second belt contact member can vary depending on the position of the tensional force adjusting member coupled to the engaging shaft.