Patent ID: 6748825
Filing Date: 2004-06-15
Classification: B25B

Abstract:
A wrench including a head defining a circular space and a crescent space communicated with the circular space, a gear including a plurality of teeth and being received in the circular space, an engagement element including a concave face formed with a plurality of teeth and a convex face and being received in the crescent space so that the teeth of the engagement element are engaged with some of the teeth of the gear and that the convex face contacts a wall of the crescent space an elastic element including a first section and a second section, with the elastic element being a spring, with the first and second sections of the elastic element being helical, with the elastic element being received in the crescent space so that the first section of the elastic element contacts the wall of the crescent space, that the first section of the elastic element includes a free end in contact with the gear and that the second section of the elastic element contacts the engagement element, wherein:when the head is rotated in a first direction, the gear tends to rotate the engagement element relative to the head in a second direction opposite to the first direction so as to enhance the engagement of the teeth so as to avoid rotation of the head relative to the gear; and when the head is rotated in the second direction, the gear rotates the engagement element relative to the head in the first direction since the convex face is not hindered via the wall of the crescent space, thus disengaging the teeth of the engagement element from the teeth of the gear so as to allow rotation of the head relative to the gear.