Patent Application
20060010696
The present invention is directed generally to hand tools, and more particularly to a hand tool with a cutting blade having cutting surfaces with a wear-enhancing coating thereon.
Hand tool cutting devices, such as utility knives and hacksaws, typically use metallic cutting blades with sharp cutting surfaces. During use, these cutting surfaces engage the material to be cut as the tool is manually moved with respect to the material to be cut. Over time, these cutting edges become dull and the user must replace the blade in what is typically a time consuming process. An increase in blade life therefore would increase the hand tool's efficiency by reducing the frequency of blade replacement.
The present invention is directed to a manually operated cutting tool, comprising: a frame having a handle portion adapted to engage a user's hand for manual movement of the frame relative to a material to be cut; a blade removably affixed to the frame and moveable along therewith during a cutting operation; the blade having a plurality of cutting surfaces and formed of a base material of a first material having a first toughness and a rigid wear-enhancing outer coating of a second material, different from the first material, external of the cutting surfaces of the base material; the second material having a second toughness more than the first toughness. The frame may be a hacksaw frame or a utility knife frame. The coating second material of the coating may comprises tungsten. Alternatively, the second material of the coating may comprise zirconium or boron carbide. Further still, the second material of the coating may comprise titanium, such as for example comprising at least one alloy material selected from the group consisting of titanium nitride, titanium cabronitride, aluminum titanium nitride, titanium aluminum nitride, titanium carbide, and titanium nickel. The coating may comprises a vapor deposition applied material, such as a physical vapor deposition applied material.
As illustrated in
The blade 20 of
The wear-enhancing coating 30 may advantageously comprise titanium. Further, the titanium containing wear-enhancing coating 30 may advantageously comprise at least one alloy material selected from the group consisting of titanium nitride, titanium cabronitride, aluminum titanium nitride, titanium aluminum nitride, titanium carbide, and titanium nickel. The coating may be a single layer, or may comprise multiple layers. The wear-enhancing coating 30 may alternatively comprise zirconium nitride, boron carbide, chromium nitride, tungsten, tungsten disulfide.
The coating 30 may advantageously be applied to the cutting surfaces by a vapor deposition process, such as the processes known as physical vapor deposition, plasma deposition, chemical vapor deposition. Just by way of example, suitable coatings may be applied to the cutting surfaces of the blades by a physical vapor deposition process by a company known as Bodycote Metallurgical Coatings, having an office in Greensboro, N.C. Alternatively, but believed to be less advantageous, the coating 30 may be applied by a dipping, sputtering, or other known coating process. It is believed advantageous if the coating 30 is applied after the formation of the cutting surfaces on the base material.
In another embodiment, the hand operated cutting tool may take the form of a tool 10a commonly referred to as a utility knife. See
The present invention may, of course, be carried out in other specific ways than those herein set forth without departing from the essential characteristics of the invention. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.
