Box cutter with autoretracting blade

An autoretracting 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, the blade having an edge directed transversely and exposed outside the housing in the extended position;
• a blade spring urging the blade slide continuously rearward into the retracted position;
• an actuator slide displaceable longitudinally in the housing independently of the blade slide between a front end position and a rear end position and provided with an externally accessible actuating formation;
• an actuator spring urging the actuator slide continuously into the respective rear position;
• coupling means including a transversely displaceable coupling member on one of the slides engageable with the other of the slides for coupling the blade slide with the actuator slide for movement of the blade slide from its retracted position into its intermediate position on displacement of the actuator slide from its rear end position into its front end position and for decoupling the slides from each other and shifting the coupling member transversely out of a path of the other slide on movement of the blade slide from its intermediate position into its extended position;
• and
• means including cam formations on the slides for displacing the blade slide into the extended position on exertion of a transverse force against the blade edge in the intermediate position of the blade slide.