1. Field of the Invention
The present invention relates to a hand tool, and more particularly to a wrench, the head of the wrench can be fixed at different angles with respect to the handle of the wrench.
2. Description of the Prior Art
The head of a conventional wrench is normally fixed to the handle, however, if a nut or a bolt to be driven is located in an unreachable corner of a narrow space, the conventional wrench is difficult to use. The inventor of the application has disclosed U.S. Pat. No. 6,928,904 “Hand tool having a quick deriving effect” and U.S. Pat. No. 7,373,861 “Pivoting assembly of a hand tool” to make a wrench whose head is rotatable with respect to its handle, so as to allow an effective use in a narrow space.
The head of the wrench of U.S. Pat. No. 6,928,904 is formed with a toothed hole, and the front end of the handle is formed a toothed locking portion. The toothed locking portion is engaged with the toothed hole of the head of the wrench. To change the angle between the head and the handle of the wrench, the handle must be lifted up to make the toothed locking portion disengage from the toothed hole of the head, so that the angle can be adjusted, and after adjustment, the tooted locking portion is inserted into the toothed hole again to make the handle fixed at the adjusted angle with respect to the head.
The head of the wrench of U.S. Pat. No. 7,373,861 is also formed with a toothed hole, and the front end of the handle is formed a toothed locking portion for engaging with the toothed hole, and similarly, the angle between the head and the handle of the wrench can also be adjusted by lifting the handle to disengage the toothed locking portion from the mounting hole.
However, the angle adjustment of the above two wrenches requires to lift the handle, namely, to make the handle move relatively to the head, so that the head can be disengaged from the handle. In such adjustment, the user has to use two hands to lift the handle with one hand and to hold the head with the other hand, this is inconvenient.
USPTO Backgrounds
USPTO Backgrounds