Abstract: A pencil sharpener having a sharpening sub-assembly for sharpening pencils, and first and second external shells having internal ribs defining surfaces for supporting the sharpening sub-assembly. Components of the sub-assembly are placed into corresponding portions defined by the internal ribs. The ribs ensure proper alignment of the components relative to the shell and each other, e.g. in the x- and y-directions. All components may be placed in the shell in a single direction, e.g. in a single axial direction (the z-direction). The components of the pencil sharpener are mounted in place upon fastening together of the first and second external shells. No internal or additional fasteners are required. The sharpening sub-assembly may include an electric motor, a gear assembly, and a cutter assembly including a cutter gear module having an annular ring gear, acting as a carrier support, and housing a pencil insertion switch and/or a receptacle presence switch.

Abstract: A paper cutter having a structural safety latch includes a sheet-supporting base having a side bearing a cutting edge. A stud is joined to the base (or cutting arm) and extends laterally therefrom transversely to the cutting edge. A blade-supporting cutting arm is pivotally mounted to the base for pivotal motion in a substantially vertical plane to cut sheets overhanging the cutting edge. The cutting arm (or base) defines a recess for receiving the stud. The recess is positioned for alignment with the stud when the cutting arm is in a closed position relative to the base. In this manner, the cutting arm is vertically moveable for cutting sheet material and laterally moveable for engaging and disengaging the recess with the stud to latch and unlatch the cutting arm when in the closed position. A safety latch for a paper cutter and a method of operating such a paper cutter is also provided.

Abstract: A paper cutter including a cutting arm pivotally mounted to a base by a pivot pin having at least two different thread sizes on adjacent portions of its distal end. A first section bears threads of a first size that are complementary to threads of a nut. A second section adjacent the first portion bears threads of a second size different from the first size. The nut is threaded onto the first section of the pivot pin having complementary threads, and then forcibly driven onto the second section of the pivot pin having mismatched threads. This positively locks the nut onto the pivot pin by deforming at least a portion of the mismatched threads. The cutting arm is thereby locked using a single nut and a second lock nut and related assembly steps are thereby eliminated. A method for assembling such a paper cutter is also provided.

Abstract: A paper cutter having a base, a first blade fixedly mounted to the base and a cutting arm pivotally mounted to the base for pivotal motion in a substantially vertical plane and supporting a second blade. The first blade has a cutting edge having a longitudinally extending burr, and is mounted to the base with the burr adjacent the base's side and extending away from the base to cooperate with the second blade for cutting. The burr-edged first blade may be positioned on the base at an angle thereto to better position the burr for acting as the cutting edge. The burr may be formed by stamping the first blade from metal sheet stock, thereby eliminating the need for traditional grinding or other processing steps, and related costs.

Abstract: A pencil sharpener having a sharpening sub-assembly for sharpening pencils, and first and second external shells having internal ribs defining surfaces for supporting the sharpening sub-assembly. Components of the sub-assembly are placed into corresponding portions defined by the internal ribs. The ribs ensure proper alignment of the components relative to the shell and each other, e.g. in the x- and y-directions. All components may be placed in the shell in a single direction, e.g. in a single axial direction (the z-direction). The components of the pencil sharpener are mounted in place upon fastening together of the first and second external shells. No internal or additional fasteners are required. The sharpening sub-assembly may include an electric motor, a gear assembly, and a cutter assembly including a cutter gear module having an annular ring gear, acting as a carrier support, and housing a pencil insertion switch and/or a receptacle presence switch.