The present invention relates to hand-held striking tools. The present invention further relates to hammers, axes and hatchets.
Hand-held striking tools are principally designed to deliver a blow to an object. Such tools are designed to drive nails, in the case of hammers, or chop and split wood in the cases of hatchets and axes. There are specialty impact tools, such as roofing striking tools, which have the physical characteristics of both a conventional striking tool and a conventional hatchet. There are also other specialty striking tools that are designed to perform specific functions, typically, when applied to the building trades.
The striking tools of the prior art share several common features. Typically, such prior art devices do not significantly insulate a user from the vibrations that result when the head of the hand-held impact tool strikes a surface. Also, the weight centerline of the head is approximately at the centerline of the shank of the prior art striking tool, such that the striking tool will balance vertically when held in a hand.
One prior art device employed a steel head forged separately of a solid steel handle in an attempt to provide a striking tool having good shock absorbing characteristics and a reduced manufacturing cost. Another prior art device employed a spring shank disposed between a striking tool""s handle and head in an attempt to absorb the shock that occurred with use. Yet another prior art device employed beams, which were parallel to a core about which a handle was formed, the beams residing in over-sized holes to purportedly function as shock absorbers.
Also, the spatial relationship of the head to the handle of hand-held impact tools has remained virtually unchanged for decades. While the prior art has attempted to address vibration reduction, the prior art has generally not addressed the energy required to yield such devices. The prior art has similarly not addressed ways to manage overstrike. Overstrike occurs when, for example, the striking surface of a striking tool misses a nail and the handle strikes the wood or other surface. Thus, the shape of hand-held impact tools has remained, for the most part, unchanged.
The shank, or upper portion of the handle, is characteristically straight in most striking tools of the prior art. As discussed above, many striking tools of the prior art are weight-balanced when held vertically in a human hand such that the striking tools do not tip under their own weight. Thus, even in cases where the handle or shank of a prior art striking tool is not completely straight, such as where the handle is bent or disposed at an angle, the tool will be weight-balanced.
It would therefore be an advantage to have a hand-held striking tool that significantly reduces the effect of vibrations arising during use. It would be a further advantage to have a hand-held striking tool that better utilizes a user""s energy. It would be yet another advantage to have a hand-held striking tool that manages the effect of overstrike.
Embodiments of the present invention provide a hand-held striking tool that significantly reduces the effect of vibrations arising during use. Embodiments of the present invention further provide a hand-held striking tool that better utilizes a user""s energy. Embodiments of the present invention also provide a hand-held striking tool that manages the effect of overstrike.
One embodiment of the present invention provides a striking tool that includes a handle, a grip molded onto the handle, a generally curved shank connected to the handle, and a head connected to the shank, the head having a striking surface. The head defines a weight center. The handle may further include an elastomeric gasket that is positioned between the shank and the head. A pultruded rod may be positioned within the shank and the handle to provide additional strength to the striking tool.
Another embodiment of the present invention provides a striking tool that includes a handle, a grip molded onto the handle, a generally curved shank connected to the handle, and a head connected to the shank, the head having a striking surface. The head defines a weight center. The head includes an overstrike flange, the overstrike flange providing an area of contact should the striking surface hit beyond its target. The head may include a nail-pulling end that is distal to the striking surface. The head may further be generally curved to facilitate the function of the nail-pulling end. The handle may further include an elastomeric gasket that is positioned between the shank and the head. A pultruded rod may be positioned within the shank and the handle to provide additional strength to the striking tool.
The present invention also provides a hand-held striking tool having a reduced vibrational Shock Factor when compared to a hammer of the prior art. The hammer of this embodiment includes a handle, a grip molded onto the handle, a generally curved shank connected to the handle, and a head connected to the shank, the head having a striking surface. The head defines a weight center. The head includes an overstrike flange, the overstrike flange providing an area of contact should the striking surface hit beyond its target. The head may include a nail-pulling end that is distal to the striking surface. The head may further be generally curved to facilitate the function of the nail-pulling end. The handle may further include an elastomeric gasket that is positioned between the shank and the head. A pultruded rod may be positioned within the shank and the handle to provide additional strength to the striking tool.
Still another embodiment of the present invention provides a method for making a hand-held striking tool having a reduced vibrational Shock Factor when compared to a hammer of the prior art. The method includes the steps of making a handle having a generally curved shape, molding a grip onto the handle, making a generally curved shank, connecting the shank to the handle or alternatively making the shank integral to the handle, making a head, the head having a striking surface, and connecting the head to the shank. The head defines a weight center. The shank may be adapted so that a connection region of the head slides into a groove or slot in the shank. The groove of the shank may include a resilient gasket interposed between the head and the shank. The shank and head may be further adapted to be connected using fasteners such as bolts. In an alternative embodiment, the method can include making the shank integral to the handle, and connecting the shank to the head.
One embodiment of the present invention provides a striking tool that includes a handle, a grip molded onto the handle, a generally curved shank connected to the handle, and a head connected to the shank, the head having a striking surface. The head defines a weight center. The head includes an overstrike flange, the overstrike flange providing an area of contact should the striking surface hit beyond its target. A horizontal plane is defined as the plane on which the striking tool rests when laid flat on its side, such as when laid on a tabletop. A first cutting plane divides the cutting tool along the length of the striking tool. The first cutting plane is perpendicular to the horizontal surface of the striking tool, and a line which is intersected by the first cutting plane is defined by a first point positioned along a center line of the handle and a second point positioned along the center line of the handle, the second point being vertically 2 inches up the handle as measured from the first point, the first point being separated by a vertical distance of 2 inches from a bottommost point, the bottommost point being defined by a bottom edge of the handle, and the bottommost point is intersected by a line that is parallel to the first cutting plane. A second cutting plane which is perpendicular to the first cutting plane and also perpendicular to the horizontal surface is disposed 2 inches down from a second center point, the second center point being defined by a top edge of the head of the striking tool. The second cutting plane defines a head portion, which is further divided by the first cutting plane into a first region and a second region. The first region is proximal to the striking surface and includes the striking surface, and the second region is distal to the striking surface and includes a claw.
In another embodiment, the weight of the first region is at least 70% of the sum of the weights of the first and second regions. In yet another embodiment, the weight of the first region is at least 7% of the sum of the weights of the first and second regions. In yet another embodiment, the weight of the first region is between 75 to 90% of the sum of the weights of the first and second regions.