Patent ID: 8776641
Filing Date: 2014-07-15
Classification: B25B

Abstract:
1. An open wrench comprising a handle and a first driving head, a rear end of the first driving head being connected to a first end of the handle, the first driving head having a clamping opening and an opening which communicates with the clamping opening so as to be mounted onto a hexagonal cylindrical head of an object, an axis of the clamping opening being perpendicular to a horizontal surface, the opening being located at the front end of the first driving head; wherein, the first driving head having two second flat portions which are located on a top and a bottom of the first driving head, each of the two second flat portions having a stepped outer flat surface and an inner flat surface which is arranged in U shape and located along the clamping opening, the outer flat surface being a U-shaped surface and located along the inner flat surface, the outer flat surface being higher than the handle, the inner flat surface being higher than the outer flat surface, a first included angle defined between the outer flat surface and the horizontal surface being between 0.5 to 2.5 degrees, a distal end of the outer flat surface located close to the opening being located closest to the horizontal surface, a second included angle defined between the inner flat surface and the horizontal surface being between 1 to 3 degrees, a distal end of the inner flat surface located close to the opening being located closest to the horizontal surface, the second included angle being larger than that of the first included angle.