Image Number 3 for United States Patent #5603162.
A utility knife includes a handle having a rod slidably engaged in the front portion. A knife blade is engaged between two boards. A plate is secured to the boards and has a rear portion for engaging with the rod. A spring biases the rod to engage with the plate. The plate may be disengaged from the handle when the rod is moved away from the plate against the spring. The boards are slightly extended outward of the handle for allowing the user to grasp the boards and for disengaging the knife blade from the handle without contacting with the knife blade.