Box cutter with deflectable safety shield

#This invention relates generally to utility knives, and in particular to hand-held box cutters of the type used by stocking clerks to open cardboard cartons, for example in grocery stores, supermarkets, convenience stores, restaurants and other retail establishments.

#Utility knives, commonly known as box cutters, include a housing or handle in which a blade is secured for cutting a variety of materials, for example paper stock, plastic sheeting, floor tiles, linoleum, carpeting, thin wood panels, wall paper, banding straps, tape and sealed plastic sacks containing bulk materials. Of special interest are sealed containers and boxes constructed of paperboard, usually corrugated cardboard, in which individually packaged items are shipped. Typically, cardboard containers are taped or glued shut. When a cardboard container is to be opened, a slicing movement is made by pulling the knife rapidly across the top or side of the container to obtain a clean, straight cut. Sharp blades are required for efficient opening of cartons, and a very sharp single-edged razor blade is commonly used for that purpose. This simple task has resulted in many on-the-job personal injuries.

#A cardboard carton is generally held steady in front of the operator with one hand and is cut by pulling the knife with the other hand toward the operator across the top or sidewall of the carton. Because such use frequently involves quick hand movements, and the cardboard presents considerable resistance to cutting, flesh wounds are likely when the knife blade travels free at the end of a cut and catches the operator's hand, fingers, arm, waist or leg. Consequently, special attention must be given to protecting the operator who must work quickly and repetitively.

#The accompanying drawing is incorporated into and forms apart of the specification to illustrate the preferred embodiments of the present invention. Various advantages and features of the invention will be understood from the following detailed description taken with reference to the attached drawing figures in which:

#FIG. 1 is a front perspective view of a box cutter equipped with the safety shield of the present invention;

#FIG. 2 is a right side elevation view thereof, showing the shield in the protective position;

#A preferred embodiment of the invention will now be described with reference to various examples of how the invention can best be made and used. Like reference numerals are used throughout the description and several views of the drawing to indicate like or corresponding parts. As used herein, “utility knife” and “box cutter” are used interchangeably to refer a hand-held knife of the type used open cardboard cartons

#The improved, adjustable-blade utility knife 10 of the present invention is illustrated in FIGS. 1-10. The utility knife 10 is designed for cutting corrugated paperboard and other sheet material and hence is ideally suited for slitting the walls of corrugated paperboard boxes and to open cardboard cartons, for example in grocery stores, supermarkets, convenience stores, restaurants and other retail establishments. The utility knife 10 can also be used to safely cut a variety of materials, for example plastic sheeting, floor tiles, linoleum, carpeting, thin wood panels, wall paper, banding straps, tape and plastic sacks containing bulk materials.

#Unlike traditional box cutters equipped with exposed blades, the cutting edge of the utility knife 10 is covered by a shield the instant the blade is withdrawn from a cut, so it is less likely to inflict injury during use or when handled casually with the blade extended. The principal components of the utility knife 10 include a handle 12, a blade holder or keeper-plate 14 which fits into the handle 12, a blade 16 which is retained in the keeper-plate 14 and a spring-loaded guard or shield 18 attached to the handle which covers the cutting edge of the blade 16 when it is not engaged against a cardboard container or other workpiece.