Tools – Hammer – Having shock absorbing means
Reexamination Certificate
2000-11-07
2002-05-14
Meislin, D. S. (Department: 3723)
Tools
Hammer
Having shock absorbing means
C081S021000
Reexamination Certificate
active
06386071
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to striking tools such as hammers, sledges, axes, mattocks and the like. More particularly, the present invention relates to an apparatus which is attachable to a striking tool to reduce recoil when a striking tool is impacted with an object.
There are many tools which are intended for striking objects or surfaces. For example, a golf club is intended to strike a golf ball, a claw hammer is intended to strike a nail, an axe is intended to strike a tree or other wood object, etc. What is common between these striking tools is that there is generated varying degrees of recoil and vibration when the striking tools hits the intended object. The recoil and vibration resulting from the strike causes the tool to lose, in part, its full striking force. Also, the recoil and vibration of the striking tool can cause shock, recoil and pain to parts of the human body in not only direct contact with the striking tool, but also body parts not directly in contact with the striking tool. An example of a claw hammer will be used to illustrate this point.
The hammer is used by gripping the handle, raising the hammer head, and swinging the head toward the nail or other object to be impacted. The hammer head is typically constructed of a relatively heavy and durable material such as steel which can repeatedly and effectively nail, pound or hatch the desired object. However, this action also causes harmful effects such as shock, vibration, and recoil to the human body. The user's posture in taking up the hammer and directing the striking force, when examined in the hand, arm and shoulder area, reveals potential for skeletal, tendon, and muscular injury. When the hammer is in a raised position, the upper arm is in contraction while the lower arm is in extension. This posture remains throughout the downward movement of the hammer's arc. Upon impact, an immediate reversal of the extended and contracted muscles is not allowed due to the immediacy of the action. This leaves the entire skeletal and tendon relationship of the arm exposed to reactive recoil, which can be as great as the amplified striking force. Prolonged and even short term usage of a hammer has proven to be injurious.
In response to the potential for injury, manufacturers began to produce hammers in varying weights, with the objective that the heavier hammers would produce less recoil upon impact. However, the heavier hammer heads have not eliminated injuries and in some cases have led to more serious injuries.
Originally, claw hammer handles were comprised of wood which was wedged into the throat of the hammer. Wood is a desirable handle as it is relatively inexpensive and also acts to somewhat soften the vibration and recoil when the hammer face is struck against an object.
The original curvature and length of the claw produced an effective fulcrum for removing nails, however, it was found that the less expensive and inferior wood handles would split and break off at the steel head joint. Therefore, heavier and more expensive woods were used, as well as synthetic materials such as plastics, fiberglass and metal for the handle. However, synthetic handles sometimes experience more severe vibration and recoil and may be more slippery, particularly after perspiration, and less “grippable” than their wood counterparts. Metal handles also experience severe vibration and recoil and also add to the overall weight of the hammer.
The length and curvature of the claw have also been reduced to prevent breakage of the handle. However, reducing the dimensions of the claw has produced a claw which is not as efficient in nail removal. In fact, the claw curvature of most hammers in use today embody a minimum and nearly ineffectual applied leverage interpretation.
Another problem associated with claw hammers is the marring of the object surface when embedded nails are removed due to the force applied to the hammer in the inverted position as the claw is moved upwardly to remove the nail. While the claw portion of the hammer is moved upwardly from the surface, the poll and face of the hammer are often pushed downward into contact with the surface, causing further damage to the surface. This is particularly a concern with finish carpentry and painted surfaces. A commonly used technique for protecting the surface has been to place a board or other material between the hammer head and the nail bearing surface. However, space constraints may limit the use of this procedure. Moreover, it is not uncommon for the board to slip out from under the hammer head, causing more damage than the removal of the nail without the use of the board.
Accordingly, there is a need for an apparatus which is easily attachable to existing striking tools for reducing the recoil when these instruments are used. There is also a need for an apparatus which reduces the shock and vibration of the striking tool while not impeding the utility of the instrument. In the particular case of the claw hammer, the apparatus should increase the utility of the claw, while preventing damage to finished surfaces. The present invention fulfills these needs and provides other related advantages.
SUMMARY OF THE INVENTION
The present invention resides in a recoil reducing apparatus for striking tools. The apparatus is configured and designed for facile application and removal from a hammer head or other striking tools such as a golf club, pick, mattock, etc., without reducing the effectiveness of the blow of the striking instrument.
The apparatus generally comprises a resiliently flexible strap that is attachable to a striking tool. The strap has a first aperture which is configured to accept an extension of the striking tool. A second aperture is spaced from the first aperture along a major axis of the strap and is configured to accept a striking portion of the striking tool. The strap is comprised of an elastomeric material, such as urethane rubber. The strap is generally planar, with the exception of optional grips which are raised from a surface of the strap. The strap also includes a flap which extends from the second aperture.
Although the apparatus is intended to be used on a variety of striking tools, and can be modified to accommodate such, it is particularly suited for use with hammers wherein the first aperture of the strap is configured to accept an extension of the hammer. Such extensions can include the handle of the hammer or a claw opposite the head of the hammer. The second aperture is configured to accept the striking head of the hammer.
The apparatus acts as a damper to reduce the shock and vibration, and thus injury, caused by repeated striking of objects. The apparatus provides this benefit without impairing the utility of the striking tool.
Other features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention.
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Kelly Bauersfeld Lowry & Kelley LLP
M.O.M. Products, Inc.
Meislin D. S.
LandOfFree
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