Tools – Hammer
Reexamination Certificate
1999-09-24
2001-01-23
Scherbel, David A. (Department: 3723)
Tools
Hammer
Reexamination Certificate
active
06176156
ABSTRACT:
FIELD OF THE INVENTION
The present invention is in the area of hand-held striking tools, such as hammers, and pertains more specifically to traction surfaces on the head of a striking tool.
BACKGROUND OF THE INVENTION
Hand-held striking tools, such as claw hammers, sledge hammers, ball peen hammers, masonry hammers, and the like, have been used by people in a variety of disciplines for centuries as leveraged devices to provide a striking force to accomplish a variety of tasks. For example, a claw hammer is commonly used by carpenters to deliver sufficient striking force to drive a nail into wood. A sledge hammer is commonly used to deliver sufficient striking force for heavy work such as driving a stake, chisel, or wedge into masonry, stone, wood, or other hard materials. A masonry hammer is commonly used to strike masonry, stone, concrete, or similar hard materials for the purpose of breaking the material into smaller pieces. For example, to remove or modify an existing concrete walkway or portion thereof, a user may strike the concrete with the striking surface of the masonry hammer with sufficient force to break the concrete into smaller pieces, making it easier to remove the material.
Another common hand-held striking tool is a ball peen hammer, which has a substantially flat surface on one end and a rounded surface on the other end of its head, and is used to deliver sufficient striking force for shaping and fitting metal, and for driving machine chisels, rivet sets, machine wedges, and other similar tools.
Some hand-held striking devices, such as claw hammers, sledge hammers, masonry hammers and the like, have a traction texture on the striking surface of the impact head. Traction textures on a striking surface are commonly provided in a crosshatch, knurled, pebble-surfaced, grainy, or any sufficiently rough pattern. The purpose of traction texture is to improve friction between the impact head of a striking tool and an object being struck. Enhancing friction between the striking surface and an object being struck enhances a user's control of the direction and strength of impact. Traction textures are typically made by machining, drilling, etching, molding or other techniques well known in the art.
A problem with the traction texture on conventional impact heads is that the method by which the traction surfaces are produced results in a large number of small protruding elements from the striking surface. For example, milling, sawing, or molding grooves intersecting on a surface results in protrusions from the surface each having a quadrilateral cross-section, and of a length equal to the depth of the grooves. In many conventional textures pyramidal protrusions are molded into a surface providing a matrix of sharp points as a traction surface.
Protruding small structures as a traction surface have several drawbacks. One is that the structures tend to wear rather quickly causing the traction to deteriorate. Another is that striking a nail, rock, or some other hard object can cause one or more of the protruding structures to break or chip off, which not only deteriorates the traction but also may be quite dangerous.
What is clearly needed is an impact head traction surface that does not rely on numerous small protrusions to provide increased friction, and instead provides a contiguous striking surface that still enhances friction, and in which the arrangement of indentions is such as to provide particular friction-enhancing geometry.
SUMMARY OF THE INVENTION
In a preferred embodiment of the present invention a traction pattern for a striking face of a striking tool is provided, the traction pattern comprising a plurality of indentions in the striking face, the indentions each forming a rectangular interface at the striking face, the indentions arranged in a rectangular matrix in the striking face, producing thereby a striking surface being the areas at the striking face between the interfaces of the indentions at the striking face.
In some embodiments the indentions are in the form of four-sided truncated pyramids, each indention therefore having a rectangular bottom surface and four sides proceeding at a common obtuse angle with the bottom surface. In some embodiments the indentions are formed of two truncated pyramids, a first forming the bottom surface of the indention and having sides at a first angle with the bottom surface, and a second beginning at a plane parallel with the bottom surface and having sides at a second angle greater than the first angle, the second forming the rectangular intersection at the striking face.
The spacing of indentions in the rectangular matrix in some embodiments is such that each edge of the rectangular intersection at the striking surface for each indention adjacent to one or more other indentions is also an edge of the rectangular intersection at the striking surface for each adjacent indention, the pattern then forming a striking surface of sharp edges intersecting at right angles. In some cases the intersections of the indentions at the striking face have sides of equal length, forming square intersections at the striking face.
In some embodiments of the invention the spacing of the indentions in the rectangular matrix is such that each edge of the rectangular intersection at the striking surface for each indention adjacent to one or more other indentions is parallel to an edge of the rectangular intersection at the striking surface for each adjacent indention, the pattern then forming a striking surface of intersecting flat surfaces at right angles, the width of the flat surfaces being a function of the spacing of the indentions, with the intersecting pattern of flat surfaces forming a contiguous striking surface.
Also in some embodiments the spacing of the indentions in the rectangular matrix is such that each edge of the rectangular intersection at the striking surface for each indention adjacent to one or more other indentions is parallel to and spaced apart from an edge of the rectangular intersection at the striking surface for each adjacent indention, and further comprising v-grooves formed in the areas between the edges of intersections of the indentions, the v-grooves forming a rectangular matrix of v-grooves in the areas between the intersections of the indentions with the striking face. The shape and depth of the v-grooves may be such that each edge of each intersection of an indention adjacent to another indention is a sharp upward-facing v-edge. The shape and depth of the v-grooves also may be such that the striking surface is a series of intersecting flat surfaces in the plane of the striking face. In still other embodiments the areas between the intersections of the indentions at the striking face are rounded from each indention to the adjacent indentions, the striking surface then being a rectangular matrix of upward-facing rounded edges.
In another aspect of the invention a striking tool having a head with a striking face, a handle interface, and a handle is provided, wherein the striking face comprises a traction pattern comprising a plurality of indentions in the striking face, the indentions each forming a rectangular interface at the striking face, the indentions arranged in a rectangular matrix in the striking face, producing thereby a striking surface being the areas at the striking face between the interfaces of the indentions at the striking face. A hammer is a good example of such a striking tool.
In various embodiments of the invention disclosed in enabling detail below, for the first time a traction surface for a hammer is provided which not only presents a contiguous surface at the striking face, avoiding breakage common with separate projections from the surface, but also provides that surface in a number of rectangular patterns of edges that enhance the traction action of the striking face.
REFERENCES:
patent: D. 57334 (1921-03-01), Hanford
patent: D. 283392 (1986-04-01), Gossage
patent: D. 398505 (1998-09-01), Gossage
patent: 1262515 (1918-04-01), Kingsley
patent: 1526251 (1925-01-01), Squier
p
Boys Donald R
Central Coast Patent Agency
Danganan Joni B.
Douglas Tool Inc.
Scherbel David A.
LandOfFree
Traction surface for a striking tool does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Traction surface for a striking tool, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Traction surface for a striking tool will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2523250