Patent Application
20120047751
The present invention relates to pivoting hand tools, and more particularly to a disassemblable and assemblable scissors and the like.
Scissors and shearing tools have long been used for numerous shearing tasks including paper cutting and food preparation, for example. When used for food preparation, scissors such as kitchen shears may include areas, such as between the scissor arms, that are difficult to thoroughly clean.
Scissors which can be disassembled for cleaning have been heretofore known but suffer various disadvantages. For example, certain disassemblable scissor designs require a user to remove a nut or other fastener at the scissors pivot point. The fasteners are generally small and can be easily dropped or lost. Removal and installation of the fasteners can be cumbersome and increase the risk of a cutting injury, for example, if users have limited manual dexterity.
Pivoting hand tools are heretofore known in which a pair of pivotable arms can be disassembled upon aligning a tabbed post on one of the arms with a slotted keyway on the other arm. For example, U.S. Pat. No. 2,619,965 describes a special purpose scissors having a tabbed post which can be disassembled upon opening the arms to an angular displacement beyond the normal range of use. This design may be suitable for special purposes requiring a relatively narrow range of angular displacements but is unsuitable for certain uses such as kitchen shears, for example wherein a wider range of angular displacements could allow accidental disassembly during normal use.
It would be desirable to provide an easily manufacturable means for controlling the angular position of disassemblable scissor arms to allow easy disassembly and reassembly and to prevent accidental disassembly during use.
Illustrative embodiments of the present invention provide a disassemblable pivoting hand tool such as, for example, scissors including handle structures which control the relative angular position of pivotable arms to allow disassembly and reassembly and to prevent accidental disassembly during use.
In an illustrative embodiment, the handle structure includes an elastic interference portion which provides an interference between the first arm and second arm at the first predetermined angle to prevent angular displacement of the arms from exceeding a predetermined angle until a disassembly pivoting force is applied to the first arm and the second arm. The elastic interference portions are deflected to release the interference upon application of the disassembly pivoting force. Upon being deflected the elastic interference portions apply an axial disassembly force to the first arm and the second arm.
The foregoing and other features and advantages of the present invention will be better understood from the following detailed description of illustrative embodiments, taken in conjunction with the accompanying drawings in which:
A disassemblable-reassemblable scissors according to an illustrative embodiment of the invention is described with reference to
As can be best seen with reference to
At least one elastic interference portion 124, 124′ is attached to at least one of the first arm 102 and second arm 110. The elastic interference portion 124, 124′ provides an interference between the first arm 102 and second arm 110 at the predetermined angle to prevent the angular displacement from exceeding the predetermined angle until a substantial pivotal disassembly force is applied to the first arm 102 and the second arm 104. In an illustrative embodiment, the predetermined angle is between about 70 degrees and 80 degrees. The tab 120 aligns with the keyway 122 at an angular displacement of between about 80 degrees and 90 degrees.
In the illustrative embodiment, the elastic interference portion 124, 124′ is deflectable to release the interference upon application of at least the disassembly pivoting force to the first arm 102 and the second arm 110. Once the interference is released, the angular displacement may exceed the predetermined angle to allow alignment between the keyway 122 and tab 120. Upon alignment of the keyway 122 and tab 120, the first arm may be separated from the second arm.
In an illustrative embodiment, a disassembly force in a direction axial to the post 108 is applied to the first arm 102 and second arm 104 by the deflected interference portions, 124, 124′. The axial disassembly force urges tab 120 into the keyway 122 and initiates separation of the first arm 102 from the second arm 104. The first arm 102 and second arm 104 may then be easily lifted apart.
In an illustrative embodiment, the tab portion includes two opposing tabs and the keyway includes two opposing slots which are alignable with the two opposing tabs. The post 108 and tab portions 120 may be formed integrally with the first arm 102, for example, or may be formed separately and fixedly attached to the first arm 102.
At least one handle structure 128, 128′ is mounted to at least one of the first handle portion 106 and the second handle portion 114. In the illustrative embodiment, the elastic interference portion 124, 124′ is formed with the handle structure 128. The handle structure may be made of an elastic material, such as, for example, an elastomer or a soft plastic.
In the illustrative embodiment, the elastic interference portions 124, 124′ are formed as extensions of the handle structure 128, 128′ with a stepped profile which is best seen with reference to
The elastic interference portion 124, 124′ is deflectable by an opposing arm 102, 110 to reassemble the first arm 102 to the second arm 110 upon application of at least a reassembly force to the first arm 102 and the second arm 110 in a direction axial to the post 108. The elastic inference portion 124, 124′ is configured to biased to a non-deflected position upon reassembly in response to the angular displacement of the first arm 102 and second arm 110 decreasing below the first predetermined angle.
Although the illustrative embodiments have been described herein with reference to a scissors, persons having skill in the art will appreciate that various other types of pivoting hand tools, such as pliers, clamps or the like, can be provided with elastic interference portions incorporated with handle within the scope of the present disclosure.
In a more general example, an illustrative embodiment prevention provides a pivoting hand tool. The pivoting hand tool includes a first arm including a first distal portion, a first proximal portion and a post protruding from a pivot point between the first distal portion and the first proximal portion. A second arm includes a second distal portion, a second proximal portion, and an aperture between the second distal portion and the second proximal portion. The post includes a shaft portion extending through the aperture to pivotably engage the first arm with the second arm for relative angular displacement between the first arm and the second arm about the pivot point.
In the example, the post includes at least one tab portion including two opposing tabs extending over at least one edge of the aperture to retain the first arm against the second arm. The aperture includes at least one keyway including two opposing slots providing clearance for the tab portion during assembly and disassembly of the first arm from the second arm. The keyway and tab are oriented such that alignment for clearance between the keyway and tab occurs only when the angular displacement between the first arm and the second arm exceeds a predetermined angle.
In the example, at least one handle structure is made of an elastic material and mounted to at least one of the first distal portion and the distal handle portion. At least one elastic interference portion is formed with the handle structure. The elastic interference portion provides an interference between the first arm and second arm at the predetermined angle to prevent the angular displacement from exceeding the first predetermined angle until a disassembly pivoting force is applied to the first arm and the second arm. The elastic interference portion is deflectable to release the first interference upon application of at least the disassembly pivoting force to the first arm and the second arm. The elastic interference portion is deflectable by an opposing arm to reassemble the first arm to the second arm upon application of at least a reassembly force to the first arm and the second arm.
The elastic interference portions have a thickness selected to allow deflection of the elastic interference portions by an opposing arm in response to a predetermined disassembly pivoting force.
While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes, omissions and/or additions may be made and equivalents presently available or as yet devised may be substituted for elements thereof without departing from the spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Moreover, unless specifically stated any use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are merely used to distinguish one element from another.
