Box cutter with autoretracting blade

A knife comprising:

• a housing;
• a blade slide carrying a blade and displaceable longitudinally in the housing between a rear retracted end position with the blade wholly received in the housing and a front extended end position with the blade extending forward from the housing and through an intermediate position;
• a blade spring urging the blade slide continuously rearward into the retracted position;
• an actuator slide displaceable in the housing independently of the blade slide between a front end position and a rear end position and through an intermediate position and provided with an externally accessible actuating formation;
• an actuator spring urging the actuator slide continuously into the respective rear position;
• a seat member on one of the slides and displaceable along a path on movement of the one slide between its end positions;
• means including a coupling member on the other of the slides engageable in the seat member on forward movement of the actuator slide from its rear position into its intermediate position for pushing the blade slide forward from its rear retracted position to its intermediate position on displacement of the actuator slide from its intermediate position to its front position;
• and
• decoupling means connected to the coupling member for disengaging the members from each other and displacement of the coupling member out of the Path of the seat member on displacement of the blade from its intermediate position into its extended position, the decoupling means including guides displacing the actuator and blade slides apart on forward movement from the rear positions.