Patent ID: 7243832

Claim:
A spring-powered stapler comprising: (a) a housing body having a front and rear end to support and guide functional components; (b) a staple feeding track formed at the bottom of said housing body having a downward facing opening for loading at least one staple magazine, to store and feed staples toward the front end of said housing body; (c) a driving blade disposed in said housing body above said feeding track and proximate to the front end of said housing body, and slidably oriented to expel one staple at a time from said feeding track, and having a temporary locked position in an upper end of sliding movement of the driving blade; (d) a power spring disposed in said housing body, with a front end linked to said driving blade and a rear end confined by a groove in said housing body; (e) a lock assembly disposed in said housing body, having a slidable lock shaft, at least one biasing spring to urge said lock shaft to slide forward, an edge on said lock shaft far pushing said lock shaft backward, and at least one locking tongue with a bottom tapered front end in a front of said lock shaft to engage said driving blade along with the front end of the power spring in the temporary locked position; (f) a handle pivotally attached to said housing body at a first location proximate to the rear end of said housing body, having a rod in contact with said power spring at a second location which is forward of said first location and between the front and rear end of the power spring, and said rod also having a wedge-shaped rearward facing surface for pushing said edge of said lock, wherein when said handle is pressed down, said rod presses down the power spring at the second location while the front and rear ends of the power spring still remain in the temporary locked and confined positions, respectively, and pushes said edge on said lock shaft rearward by the wedge-shaped rearward facing surface on the rod for unlocking said driving blade when the handle is pressed further downward to a predetermined location; and (g) a return spring disposed in said housing body with one end linked to the power spring and another end linked to the housing body for urging said power spring and said driving blade upward to the locked position.