In order that those skilled in the art can further understand the present invention, a description will be provided in the following in details. However, these descriptions and the appended drawings are only used to cause those skilled in the art to understand the objects, features, and characteristics of the present invention, but not to be used to confine the scope and spirit of the present invention defined in the appended claims.
Referring to
A body 1 has handle 10. A receiving groove 23 longitudinally penetrating through the handle 10.
One end of the handle 10 has an enlarged head 20. One end of the head 20 is extended with a fixing jaw 21. An upper side of the head 20 is formed with a sliding surface 22. The head 20 has a transversal sliding trench 22. The sliding trench 22 is communicated to the receiving groove 23.
A movable jaw 24 is installed in the sliding trench 22. A directional control element 25 is installed in the receiving groove 23 and is engaged to the movable jaw 24. When the directional control element 25 is rotated, the movable jaw 24 is driven to move long the sliding trench 22 so as to change the distance between the fixing jaw 21 and movable jaw 24. However, above mentioned structure is known in the prior art. The directional control element 25 may be for example a worm rod as shown in the drawing, or a button or a wedge member, etc.
The main feature of the present invention is that a fixing surface 211 of the fixing jaw 21 and a movable surface 241 of the movable jaw 24 facing to the fixing surface 211 are parallel. A cambered or trapezoidal protrusion 212 is formed at a lower side of the fixing surface 211. A receiving recess 214 is formed at a lower side of the fixing surface 211 for receiving an apex B of a nut. An inclined resisting surface 213 is formed between the recess 214 and the sliding surface 22 for resisting a nut.
A cambered or trapezoidal movable protrusion 242 is formed at a lower side of the movable surface 241. The movable surface 241 has a long recess 244 between the protrusion 242 and the movable surface 241 for receiving an apex B1 of a nut. A line Y is defined from a top end of the fixing surface 211 to the sliding surface 22. A line X is defined to be an axial line of the sliding trench 22. In the present invention, the angel Θ between the line Y and the line X is less than 90 degrees, preferably, between 65°˜85°. More preferably, it is 74°.
Referring to
Referring to
Referring to
In above design, the apexes B, B1 are in the recesses 214, 244, as illustrated in
Advantages of the present invention are that: the apexes of the nut will not round. Thereby for the nut with rounded apex, the spanner of the present invention can drive it well.
The present invention is thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.