Double Action Coil Spring Improvement Obviates Broad Claim Including Gas Spring Disclosed as Single Action
First, Teague discusses prior art, single-action coil springs that always push the bed towards the closed position. As Teague recites, in those beds, "the coil springs also exert forces holding the bed in the fully closed position." Teague, col. 1, ll. 51–55. Such springs, in this application, would produce a force always urging the tread base towards the closed position—exactly the type of mechanism that Icon argues its claims require. While the passage concerns coil springs rather than gas springs, Teague explicitly discusses the interchangeability of gas springs and coil springs. Teague, col. 3, ll. 61–65. Therefore, Teague provides an example of a mechanism clearly satisfying Icon’s claim limitation.
Next, Icon’s application discusses the gas spring in connection with a "lift assistance assembly." ’624 patent, col. 15, ll. 3–25. Similarly, Teague is directed at a "counterbalancing mechanism," intended to support the weight of a bed as it opens and closes. Teague, col. 1, ll. 5–34. One skilled in the art would naturally look to prior art addressing the same problem as the invention at hand, and in this case would find an appropriate solution. Indeed, while perhaps not dispositive of the issue, the finding that Teague, by addressing a similar problem, provides analogous art to Icon’s application goes a long way towards demonstrating a reason to combine the two references. Because Icon’s broad claims read on embodiments addressing that problem as described by Teague, the prior art here indicates a reason to incorporate its teachings.
Finally, Teague provides a mechanism such that the bed "has two stable rest ositions." Teague, col. 1, ll. 35–38. It describes, "as the center of gravity of the bed
passes over the pivot axis . . . gravity tends to hold the bed in its fully closed position." Teague, col. 1, ll. 47–51. When folding the treadmill described in Icon’s application, "[t]he tread base 434 is rotated until the center of gravity 440 is displaced clockwise past the vertical 446 a distance 448 selected to stably retain the tread base 434 in the second position." ’624 patent, col. 12, ll. 29–32. The striking similarity between Icon’s application and Teague clearly illustrates the similarity of problems they address and solutions to that problem, further supporting the idea that one skilled in the art would combine Teague with Damark.
The aforementioned connections between Teague and Icon’s application provide a sufficient basis to conclude that one skilled in the art would combine the teachings of Teague and Damark.
Contrary to Icon’s argument, the passage in Teague describing single-action springs does not indicate the undesirability of those springs for Icon’s application. At most, Teague only teaches away from single-action springs in the context of decreasing the opening force. Icon argues that the gas spring limitation in its application must increase the opening force provided by gravity. As Icon recognizes, Teague instructs that single-action springs provide exactly that result. Indeed, "[t]he combination of familiar elements according to known methods is likely to be obvious when it does no more than yield predictable results." KSR, 127 S. Ct. at 1739. Accordingly, Teague does not teach away from using single-action springs in Icon’s invention.
Icon next asserts that the dual-action mechanism disclosed in Teague provides exactly the wrong type of force for Icon’s purpose, rendering the combination inoperable. As we have discussed, Icon’s argument may have carried some weight with more narrow claims, which it could have obtained by amendment. But faced with broad claims encompassing anything that assists in stably retaining the tread base, we reject Icon’s argument. While Icon’s claim would also read on a mechanism providing a consistent closing force (a single-action spring), one skilled in the art could view the Teague mechanism (a dual-action spring) as assisting in stably
retaining the tread base, just as it creates a stable rest position for the bed in Teague. See Teague, col. 1, ll. 35–38 (describing the invention as "an improved counterbalance mechanism in combination with a bed, whereby the bed has
two stable rest positions").
Finally, Icon argues that the counterweight mechanism from Teague uses a large spring that would overpower Icon’s treadmill mechanism, thus producing a
result inoperable for its intended purpose. Icon correctly states the principle
that a reference teaches away from a combination when using it in that combination would produce an inoperative result. See McGinley, 262 F.3d at 1354. But we do not ignore the modifications that one skilled in the art would make to a device borrowed from the prior art. Optivus Tech., Inc. v. Ion Beam Applications, S.A., 469 F.3d 978, 989–90 (Fed. Cir. 2006). One skilled in the art would size the components from Teague appropriately for Icon’s application, therefore producing an embodiment meeting Icon’s claims.
Therefore, Icon’s arguments fail to convince us that Teague teaches away from Icon’s claims. Teague discloses two types of mechanism that would satisfy Icon’s gas spring limitation, and does not indicate the undesirability or unsuitability of either mechanism for Icon’s purpose. To the contrary, one skilled in the art would naturally look to Damark and Teague, finding reason to combine them; forming that combination would produce a device meeting all of Icon’s claim limitations.