Patent attributes
A returning assembly of a spanner includes a driving portion having a receiving space for receiving a driving head, a switch unit and an ejecting unit having a truncated conic shape; a radial direction of the driving head having a slightly inclined buckling surface; the buckling surface and an inner wall of the receiving space being formed with a semilunar buckling space for receiving the ejecting unit; the ejecting unit serving for controlling the returning directions of the driving head. A round cylindrical positioning portion extends from the larger end of the truncated conic ejecting unit. The driving head has a driving block which are arranged at an axial direction of the driving head for installing a socket or other driving assembly. A switch unit is installed in the driving head. The switch unit has a control end projected from the driving portion and a resisting end.