Anti-slip type electric drill chuck

An anti-slip type electric drill chuck, comprising:

• a body having one end connected to a transmission shaft of an electric drill motor, said body being provided with a first ring and a second ring projecting from an outer periphery of a shaft securing end thereof, the other end of said body being provided with a shaft hole, the surface being provided with angularly arranged guide grooves for intersecting said shaft hole;
• a plurality of pawls that are slidable in each of said guide grooves, the outer side of each of said pawls forming a threaded surface;
• a bearing nut, the center of which is provided with a tapered threaded hole for locking said threaded surface of said pawl, the outer periphery of one end thereof being provided with teeth;
• a ball ring provided at the other end of said bearing nut;
• a washer provided between said ball ring and said second ring of said body;
• a check nut protective sleeve fitted around said bearing nut and having one end provided with a plurality of elastically movable pointed portions to correspond to said teeth of said bearing nut for insertion thereinto, the other end thereof being provided with a packing ring for stopping said washer so as to enclose said bearing nut, said ball ring and said washer as a unit, said being nut being locked on said threaded surface of said pawl, said packing ring being provided at said second ring of said body;
• a drive annular block extending outwardly of said body and having one end portion secured in an open end edge of said bearing nut, with the other end portion thereof exposed from said body;
• a front housing sleeve positioned at said end portion of said body to enclose said drive annular block, said check nut protective sleeve and said bearing nut, and rotatable with the end portion of said drive annular block that is exposed from said body so as to be positioned;
• a rear housing sleeve which is a substantially U-shaped hollow housing sleeve fitted on said first ring of said body.