Patent ID: 7673779

Claim:
A combustion-powered fastener-driving tool, comprising: a combustion-powered power source including a cylinder head and a combustion chamber defined by said cylinder head, a valve sleeve, a cylinder and an upper surface of a reciprocating piston; said valve sleeve reciprocable relative to said cylinder head between a rest position and a pre-firing position; said valve sleeve having a range of positions between a first sealing position in which said combustion chamber is closed, and said pre-firing position in which said valve sleeve is prevented from further movement towards said cylinder head; a lockout device mounted to the tool and having an actuated position configured for preventing movement away from said cylinder head of said valve sleeve beyond said first sealed position to open said combustion chamber; and said lockout device including a fixed electromagnetic component secured to said power source and a magnetically attractable movable component, being movable relative to said fixed component and having a first portion secured to said valve sleeve for common reciprocal movement and a second portion movable relative to said first portion and said valve sleeve, wherein after magnetic engagement of said fixed electromagnetic component and said second portion of said movable component, said valve sleeve, being movably connected to said second portion of said movable component, is movable from said first sealed position to said pre-firing position.