Abstract: Sheathed knives are disclosed that have a blade that is ejected via a button triggered spring longitudinally from the sheath into a locked use position in which the sheath then serves as the handle for the blade in the nature of a dagger, an elongated handled rod that slides within the sheath to draw the blade from its use position back into the sheath where it is automatically locked in a spring loaded sheathed position for triggered release into its use position and safety features to prevent the blade from accidental movement in or out relative to the sheath.

Abstract: Folding knives having a longitudinal sheath handle with a channelled body portion into and out of which a blade pivots about an axis normal to a common plane of the handle and blade between a sheathed position within the handle through an arc to a use position external of the handle and a lock to automatically lock the blade in such use position upon completion of the unsheathing movement, which lock is manipulated for manual return of the blade from its use position to its sheathed position are improved by addition of a double action feature provided by an actuator unit that is cocked by manual rotation of the blade from the use position back into the sheathed position and a trigger to uncock the actuator unit for automatic quick forced rotation of the blade from its sheathed position all the way to its use position.