Patent Application
20100183402
1. Field of Invention
The present invention relates to a nut and, more particularly, to a tapping nut.
2. Related Prior Art
A threaded bolt and nut are often used for fastening purposes. A thread is formed on the threaded bolt. A corresponding thread is formed on an internal side of the nut. Thus, the threaded bolt can be engaged with the nut. In consideration of smooth rotation on one hand, there is an appropriate clearance between the threads. In consideration of firm engagement on the other hand, there is provided a washer between the head of the threaded bolt and the nut or an additional nut against the nut. However, the washer often cannot ensure the firm engagement of the threaded bolt with the nut. Sometimes, there is no room for such an additional nut.
In some other times, the length of a threaded bolt can only be determined before it is used. In this case, a smooth bolt is made of an excessive length so that it can be cut to an appropriate length for use. Then, a tool is used to tap the smooth bolt with a thread so that a threaded bolt is made. It is however troublesome to carry such a tool. Moreover, it is a waste of time to use such a tool to tap the smooth bolt and then engage a nut with the threaded bolt.
The present invention is therefore intended to obviate or at least alleviate the problems encountered in prior art.
It is the primary objective of the present invention to provide a nut for fast tapping of and firm engagement with a bolt.
To achieve the foregoing objective, the nut includes a cylindrical tunnel, a conical tunnel, a plurality of slits and a plurality of edges. The diameter of the cylindrical tunnel is marginally smaller than that of a bolt to be tapped by the tapping nut. The conical tunnel extends and expands from the cylindrical tunnel so that the bolt can be introduced into the cylindrical tunnel through the conical tunnel. The cutting edges are formed on an internal side of the nut. Each of the cutting edges extends along a related one of the slits so that the cutting edges can cut the bolt while the slits allows the removing of debris of the bolt.
Other objectives, advantages and features of the present invention will become apparent from the following description referring to the attached drawings.
The present invention will be described via the detailed illustration of the preferred embodiment referring to the drawings.
Referring to
The conical portion 11 is in the form of a conical frustum. There are four slits 14 cut into the conical portion 11. The slits 14 are in the form of a segment of a helix. Four cutting edges 140 are formed on an internal side of the conical portion 11. Each of the cutting edges 140 extends along a related one of the slits 14. The cutting edges 140 are used to tap a thread 25 on the bolt 20. Debris of the bolt 20 can be removed through the slits 14. A plurality of blocks 12 is formed on an external side of the conical portion 11. The blocks 12 can be disposed in corresponding recesses defined in a tool that is operable to rotate the tapping nut 10.
A thread 17 is formed on an internal side of the cylindrical portion 15. The thread 17 is used for engagement with the thread 25. A plurality of blocks 16 is formed on an internal side of the cylindrical portion 15. The blocks 16 can be disposed in corresponding recesses defined in the tool that is operable to rotate the tapping nut 10. The blocks 16 and the blocks 12 are preferably alternately arranged.
Referring to
Referring to
The present invention has been described via the detailed illustration of the preferred embodiment. Those skilled in the art can derive variations from the preferred embodiment without departing from the scope of the present invention. Therefore, the preferred embodiment shall not limit the scope of the present invention defined in the claims.
