Fastener driver with safety device

Claim 1

A driver for fasteners, comprising a. a housing having a handle and a fastener exit, b. a magazine mounted in the housing for presenting the fasteners seriatim to the said fastener exit, c. means mounted in the housing for driving a fastener through the exit into a surface, said means including a spring-loaded hammer with a driver blade adapted to strike the fastener, the hammer being slidable between a second position relatively close to the exit and a first position relatively far from the exit, d. an actuator which is operable to cause the said driver blade to strike said fastener when the hammer is in the second position but which operation does not effect the hammer when the driver blade is in the first position, the actuator including a lifter which is provided to lift the hammer and then release it for the driving operation, the blade extending out of the exit when the hammer is in the second position, and lying substantially entirely within the housing at the exit when the hammer is in the first position, and e. a spring mounted in the housing and normally holding the hammer in the second position but allowing the hammer to move to the first position when the fastener exit is pressed against a surface, the hammer including a recess and the lifter being biased toward a starting position in which it engages the recess when the driver is in its first position and does not engage the recess when the driver is in its second position, the pressing of housing and the exit against the surface pushing the blade which in turn moves the hammer to the first position at which the recess can be engaged by the lifter.