From Bill Goodwine's Wiki
Jump to navigationJump to search

Homework 3: Arguments on Non-Obviousness in Graham v. John Deere

The patent in question:

Patent 2627798: Clamp for Vibrating Shank Plows

The prior art:

Patent 2493811: Vibrating Plow and Mounting Therefor

Patent 2739518: Shank Holder

Arguments for Obviousness

When taking into account the prior art of both Graham's previous patent, 2493811, and the so-called "Glencoe Clamp," 2739518, it must be seen that Graham's most recent patent, 2627798, is invalid. Although '798 is useful and technically novel, the improvements made are not sufficient to make it non-obvious to a person having ordinary skill in the art. '798 itself is simply an improvement upon the design of Graham's earlier work, '811. In this respect, the design of the two devices is very similar, with small changes. First, the hinge has been attached above the shank, as opposed to below, so that the shank itself no longer touches the base plate of the clamp. This was done to reduce the wear on the upper plate, as the shank would rub against it as it moved up and down. Second, the shank is now secured to the hinge by a nut and bolt at the front, a stirrup at the rear and the spring rod passing through a slot, as opposed to only the spring rod. These additions provided more attachments between the hinge and shank, which lowered the stress and wear on the spring rod. Graham's claims made a point that these attachments also maintained continuous contact between the two components, shank and hinge. These changes certainly set '798 apart from '811, but whether the changes are non-obvious is not so clear. It would seem apparent from a simple analysis of '811 that as the shank moves it would wear against the plate. The easiest solution, one would then think, is to change its placement so that it could not. How simple a solution, then, to simply flip the shank and hinge over, and the parts no longer contact. As for the extra attachments, adding a nut and bolt to secure it at the front and stirrup at the rear are hardly impressive changes.

Add to the fact that there is another prior art, the Glencoe Clamp. Although the Glencoe Clamp appears at first glance to be different, having its hinge below the shank, and not having the spring rod go through both the shank and hinge, it can be seen that mechanically, they both accomplish the same purpose of improving upon '811. Despite the hinge being located below the shank, it can be seen that its placement allows the shank to move without contacting the upper plate, which was precisely the purpose of Graham's first change in '798. Likewise, although the spring rod does not go through both shank and hinge, this does not change the way that the machine moves, and in fact, the attachment of the shank to the hinge is accomplished by a stirrup in the rear and a nut and bolt at the front end of the shank, just as in '798. Graham's goal of reducing the wear on both parts is easily met by this device, which does not allow contact between the upper plate and shank, and attaches the shank to the hinge without even using the spring rod. Likewise, Graham's emphasis in changing his claim to state that '798 maintained continuous contact between shank and hinge is met by the Glencoe Clamp, with the exact same attachments. Therefore, a patent which seemed to be barely enough of an improvement over its predecessor, now becomes entirely obvious. A device which accomplished the desired goal of the changes in a mechanically equivalent fashion was already made before Graham patented his own solution. Furthermore, since it was made earlier, one can assume then that Graham's non-obvious changes were in fact quite obvious, as another company was able to look upon and improve his previous iteration in under 5 short years. There can be no doubt then, that '798 is obvious, and therefore, an invalid patent.

Arguments for Non-Obviousness

Although '798 is similar to '811, it has two significant changes in the switching of the shank and hinge plate, and the attachment of the one to the other. These are a much needed solution to the problem of wearing out both the upper plate and spring rod, two important components to the design of the plow. Furthermore, these parts can be difficult and expensive to replace. '798 solves these problems in a novel and not entirely obvious fashion. Although switching the placement of shank and hinge may at first seem an entirely mundane task, it requires a different design in order to effectively achieve the same plowing ability. Without sandwiching the shank between the hinge and upper plate, it needed to be attached in a different manner in order to maintain the same functionality. This required the nut and bolt assembly, as well as the stirrup, which were not carelessly put on, but rather also chosen in order to take stress off of the spring rod. Likewise, although simply flipping a part over may seem simple, where the hinge attached on the clamp casing and the point it would swing around are important design decisions, which are essential the operation of the new device.

The Glencoe Clamp, then, is the only prior art left to consider. Although the Glencoe clamp may accomplish the same purpose, it does in fact utilize a different design. Furthermore, this design restricts the length of the shank that is attached to the hinge, which is inferior to the design of '798. Because the shank not only maintains continuous contact between itself and the hinge, but also maintains it the entire length of the hinge itself, it is more resistant to breakage. This allows a better absorption of the impact forces generated when the plow hits larger rocks, as there is in an increased flexion allowed along the longer length, which prevents the stress from focusing at a smaller point and creating a fracture. This is in fact not a minor point, as the entire purpose of the changes in '798 was to reduce wear, in order to prevent failure. A fracture would indeed be a failure, and '798 accomplishes this better than the Glencoe Clamp, by using its own design that the Glencoe Clamp mimics mechanically in certain respects, but does not actually duplicate or achieve. Because of this, '798 is substantially different from both '811 and the Glencoe Clamp, and the choice of its design, although subtle, can be seen to have a purpose with not inherently obvious benefits, and therefore must be a valid patent.