Patent attributes
The present invention is to provide a knife including a blade and a handle, wherein the blade has a first end provided with a projection and two resilient elements, each resilient element has one end protrudingly provided with an engaging portion, and the handle has a receiving space for receiving the blade and has a first track and two second tracks provided longitudinally thereon. The projection can be movably inserted in the first track. The distance between each pair of the corresponding ends of the second tracks corresponds to the distance between the engaging portions. Thus, when the engaging portions are respectively engaged in a pair of the corresponding ends of the second tracks, the engaging portions cannot move along the second tacks, such that either the blade is completely received and positioned in the handle, or a second end of blade is extended and positioned outside the handle.