Patent ID: 7080456

Claim:
A knife assembly, comprising: a knife having a blade, a handle at an end of the blade and a lock portion on the handle; a rigid sheath having an elongated bottom wall and two upright sidewalls, between which a slot is formed, wherein each of the sidewalls has a restricting portion over the slot and the blade of the knife is received in the slot and under the restricting portions, and at least one lock device provided on the sheath for movement between a lock position, in which the lock device is engaged with the lock portion of the knife to secure the knife, and an unlock position, in which the lock device is disengaged with the lock portion of the knife, so that the knife is free to be taken out of the sheath, wherein the lock device has a rod and a pressing plate and the pressing plate is extruded out of the sheath for manipulation of the lock device and the lock portion of the knife is a hole or a slot to be detachably engaged with the rod of the lock device.