Patent ID: 9669469
Date: 2017-06-06
CPC Classifications: B23B,B23Q,Y10T

Claim:
1. A coupling device comprising: a foundation comprising a chamber therein and a perforation on a surface thereof and connecting to the chamber; a tube engaged with the perforation of the foundation, the tube comprising a plurality of through holes; a plurality of balls respectively movably provided in each of the through holes of the tube; a piston base received in the chamber and fitted to an outer surface of the tube, the piston base being capable of being moved along an axial direction of the tube between a first position and a second position, the piston base comprising an inner surface facing the outer surface of the tube and a circular groove being formed on the inner surface of the piston base, a part of each of the balls being received in the circular groove in response to the piston base being at the first position, the inner surface of the piston base further comprising a abutment surface abutting against each ball with an area in response to the piston base being at the second position; the piston base comprising a main body and a loop seat fitted on the outer surface of the tube; the abutment surface and the circular groove being provided on the loop seat; the main body being engaged to an outer surface of the loop seat; an outer surface of the main body abutting against walls of the chamber of the foundation; the loop seat comprising a pressing ring and an abutment ring; the main body being engaged to an outer surface of the pressing ring; the pressing ring comprising a first stop surface; the main body comprising a second stop surface; the abutment ring being held between the first stop surface and the second stop surface; and the abutment surface and at least a part of the circular groove being provided on the abutment ring.