Patent ID: 8056241

Claim:
A knife comprising: a housing comprising: a blade aperture; a trigger aperture; and a stop pin; a blade connected to a blade shuttle, the blade and blade shuttle substantially enclosed within the housing when the blade shuttle is in a retracted position, the blade extended from the housing when the blade shuttle is in an extended position; a shuttle spring connected to the blade shuttle and adapted to convey the blade shuttle to the retracted position; a blade trigger comprising a cavity, the blade trigger pivotally coupled to the housing and accessible at an exterior of the housing through the trigger aperture, the blade shuttle conveyed from the retracted position to the extended position when the blade trigger pivots from a rest position to an engaged position; and a trigger lock comprising a projection, the trigger lock substantially enclosed within the cavity and accessible at the exterior of the housing through the blade trigger, the trigger lock pivotally coupled to the blade trigger, the projection in contact with the stop pin when the blade shuttle is in the retracted position, the blade trigger substantially prevented from pivoting from the rest position to the engaged position when the projection is in contact with the stop pin, the projection released from the stop pin upon rotation of the trigger lock, the blade trigger pivotable from the rest position to the engaged position when the projection is released from the stop pin.