Patent 4252138: Adjustable Crutch for Raising From Seated to Standing Position
Date Issued: February 24, 1981
The foundation of the invention is a crutch with a length that can be manually adjusted through the use of a lever. The user reduces the height of both crutches to a minimum while in a seated position and then places his weight upon both crutches. In order to raise to a standing position, the user alternately shifts his weight from one crutch to the other, while operating the lever on the crutch that is not supporting any weight. By operating the lever of the non supportive crutch, the user can increase the length iteratively until both crutches are at the proper height for standing position.
Evaluation of Patent
Regarding Cases: Hotchkiss v. Greenwod, A&P Tea Co. v. Supermarket Corp., and Lyon vs. Bausch & Lomb
Overview of Referenced Patents:
The most recent reference cited by Patent 4252138, the height adjustable crutch, was Patent 3738674, the “ski equipped crutch,” which describes an invention predicated on the design of an instrument that can be utilized as both a ski/ski pole and a crutch. The patent for the “ski crutch” highlights the ability of the ski portion of the instrument to fold up and essentially form a regular shaped forearm crutch. Also included in the design outline is the presence of a slip-resistant member to prevent slippage in snowy conditions and a claw like appendage that can be employed as a brake when the “ski crutch” is used for downhill skiing. Like the height-adjustable crutch, the “ski crutch” is aimed at not only facilitating the typical motion of a handicapped individual, but also assisting the individual in situations where a typical crutch cannot provide such help. The focus of this design on the ability to manipulate the crutch to fit two specific purposes is the most crucial element. While Patent 4252138 has no ski attachment or brake mechanism, it utilizes the same concept of adjusting the shape and size of the crutch for two specific scenarios: standing and sitting.
Another patent referenced is Patent 2960095, which describes a walking cane that can easily be converted into a crutch. Using sliding and revolute joints, the handle of the walking stick can be converted into the arm rest for the crutch and the height of the support device can be adjusted to meet the needs of the user. The major connection between this patent and the height adjustable crutch is the ability of the crutch to be easily adjusted, specifically the overall height of the instrument. The way in which the crutch is adjusted though is different for each design, as the walking cane/crutch has to be adjusted near the center of the cane by the user, an action that cannot be done easily while maintaining one’s balance. The more recent design allows for adjustment of the crutch height through the manual operation of a lever, which allows for the handicapped individual to rise from a seated to standing position. Both designs however maintain the same shape (only reduced or increased in length) during the adjustment process.
Analysis of Relevant Cases:
Hotchkiss v. Greenwood
The height adjustable crutch would easily be patentable according to the criteria set forth in Hotchkiss v. Greenwood (1850), as the design instituted required more “skill and ingenuity ….than was possessed by an ordinary mechanic.” Although the cane/crutch allows for the adjustment of height, the newer crutch provides the user with dual levers to raise the height of each crutch, while maintaining the weight bearing support of the device. The “ski crutch” does not even contain a height adjustment feature, as the only real connection between the two designs is the simple premise of manipulating a crutch for various purposes. While the inventor certainly received inspiration from these previous designs, the improvements made upon the original inventions are significant and by no means “destitute of ingenuity or invention.”
A&P Tea Co. v. Supermarket Corp.
According to the precedent set forth by A&P Tea Co. v. Supermarket Corp., the height adjustable crutch would again be patentable, as it constitutes an invention that is innovative enough to “promote the Progress of Science and useful Arts.” The design of a crutch that provides the user with the ability to adjust the height through the use of a lever is worthy enough of an invention, as none of the reference patents outline a design that could accomplish the same feat as easily. Furthermore, the height adjustable crutch provides an important service to handicapped individuals, as it is designed specifically for the assistance of an individual attempting to rise from a seated to standing position. Thus, because the new design accomplishes a task that neither of the two previous inventions accomplishes it can be stated that the product upholds the purpose of patents, which is “to promote the Progress of Science and useful Arts.”
Lyon v. Bausch & Lomb
Lyon vs. Bausch & Lomb (1955) addresses the issue of nonobviousness, which stipulates that the change the proposed design is based upon must not be “obvious to a person having ordinary skill in the art.” The stipulations presented by the nonobviousness clause are more difficult to adhere to for the height adjustable crutch; however, it may still past the test. While it is not unbelievable that an average designer in the field of equipment for disabled individuals could develop an idea for a adjustable crutch that allows the user to rise from a seated to standing position, the combination of developing the concept and instituting the mechanical components is far harder to replicate. Thus, it can be argued that although an average mechanic could have developed the adjustment mechanism utilized in Patent 4252138 and an average crutch designer could have proposed the design idea, the culmination of both the creativity and technology in a single design proposal allows for adherence to the nonobviousness stance.
U.S. v. Adams
Overview of Litigated Patent
The patent under litigation in U.S. v. Adams is U.S. No. 2,322,210, issued in 1943. The invention is a nonrechargeable electrical battery comprised of two electrodes, one made of magnesium and the other of cuprous chloride, with battery fluid of either plain or salt water. The goal of the aptent was to provide constant voltage without the use of acids or the generation of dangerous fumes. Furthermore, the battery was intended to be relatively light in weight and able to be manufactured and distributed to the trade in a dry condition and rendered serviceable by simply filling the container with water.
Conclusion of Non-Obviousness
The prior art is based primarily on six patents, including, the Skrivanoff patent, Wensky patent, Codd treatiste, Wood patent, and Niaudet treatise (which consists of the Marie Davy cell adn De La Rue's subsequent variations). A comparison between the Adams Patent and the prior art reveals that the most significant addition to the battery model made by Adams is the concept of a device that is "water-activated," as none of the previous patents mention such a design. The use of magnesium is used in several of the previous patents, including Wood, Codd, and Skrivanoff. While coprous chloride is not clearly indicated by any of the patents as a usable electrode, it is referenced by the Wensky patent as a necessary addition (in salt form) to the electrolyte solution. Thus, the Adams patent relies on three major attributes for patent validity, water-activation, coprous chloride (as a electrode), and marketability/commercial success. In Anderson's Black Rock Inc v. Pavement Co., the distinguishment between commercial success was made, as it was stated that the marketability of the product "is relevant to commercial success, not to invention," so it can not be used alone to uphold the validity of a patent. Fortunately, the fact that the battery is water activated is enough to separate the Adams invention from the prior art. As none of the previous patents reference this particular attribute, the requirement of novelty is validated. As for nonobviousness, the primary reasons for support can be found in the results produced by the device, as they proved to be both unexpected and far surpassing the then-existing wet batteries. Another important consideration in the conclusion of nonobviousness is the the pre-existing results that would discourage research and subsequent discovery of the conclusions made by Adams. At the time of Adams invention, it is was widely believed that batteries which operate on an open circuit and which heated in normal use were not practial. Also, it had been determined that water-activated batteries were successful only when combined with electrolytes detrimental to the use of magnesium. Thus, it can be concluded that a person with reasonable skill in the art would have been unlikely to ignore these widely accepted conclusions and create the device that Adams created. Further support of nonobviousness can be found in the fact that the Navy expressed disbelief in Adams product at the time of its invention. All of these facts strongly support the conclusion of nonobviousness.
Conclusion of Obviousness
A conclusion of obviousness can most easily be realized through the analysis of earlier cases, such as Anderson Black Rock. Pavement Co. and KSR International Co. v. Teleflex Inc. As stated in the conclusion for nonobviousness, the marketability and commercial success of the water-activated battery can be nullified in the evaluation of the patent validity, as "that is relevant to commercial success, not invention." (As stated in Anderson v. Pavement) Furthermore, one of the major attributes of the Adams patent is the combination of magnesium and coprous chloride, both of which had previously been reference in earlier patents. The use of magnesium was referenced by Wood, Codd, and Skrivanoff, while coprous chloride was refrenced in Wensky, albeit not as an electrode. However, the existence of both of these elements in the art of battery design supports the conclusion that the combination of both of them (even as electrodes, particularly since magnesium was already used as an electrode) would be obvious to a person of ordinary skill in the art. This can be seen in KSR v. Teleflex, as it was determined that the combination of the Asano patent with a pivot-mounted pedal position sensor would be obvious to a person to a reasonably skilled individual because there was an existing market place for the development of mechanical pedals into eletronic pedals and prior art provided methods to achieve this advance. Thus, both the Adams patent and the Teleflex patent revolved around the combination of an existing design/element (magnesium for Adams, Asano patent for Teleflex) with an existing, yet unrefined design/element (coprous chloride for Adams, pivot mounted pedal for Teleflex). Similar support can be found in Anderson v. Pavement, as placement of a radiant heat burner on a standard paving machine was declared unpatentable because the use of radiant heat was an old technology and the placement of a mechanism would be obvious to a person of reasonable skill in the field. Similarly, the use of coprous chloride as an electrode, rather than as a salt in the electrolyte, as in the Wensky patent, involves the use of the same element in a different portion of the battery, which should be obvious. Both KSR International v. Teleflex Inc. and Anderson Black Rock.v. Pavement Co. can be used to support the obviousness of the Adams patent.