Appeal No. 2003-0387 Page 10
Application No. 09/772,275
Ascertainment of the differences between the prior art and claim 1
After the scope and content of the prior art are determined, the differences
between the prior art and the claims at issue are to be ascertained. Graham v. John
Deere Co., 383 U.S. 1, 17-18, 148 USPQ 459, 467 (1966).
Based on our analysis and review of Hawthorne and claim 1, it is our opinion that
the only difference is the relationship between the wedge angle 2 and the wedge spring
force P as defined by the two equations set forth in claim 1.3 While Hawthorne does
teach a wedge angle 2 of 30° falling within the appellants preferred range of 28° to
about 32°, Hawthorne does not teach that the wedge spring force P would be that
defined by the two equations set forth in claim 1 when the wedge angle 2 was 30° and
the other variables in the two equations were determined from the rail car truck.
Similarly, while Hawthorne does disclose a wedge spring force P of 3160 lbs. falling
within the appellants preferred range of about 1350 lbs. to about 7300 lbs., Hawthorne
does not teach that the wedge angle 2 would be that defined by the two equations set
forth in claim 1 when the wedge spring force was 3160 lbs. and the other variables in
the two equations were determined from the rail car truck.
3 The specification provides (e.g., page 1, first paragraph) that the present invention teaches the
desired relationship between friction wedge angle, friction coefficient, wedge spring force and wedge
width (as defined by the two equations set forth in claim 1) that provides a friction wedge that will
simultaneously produce a very high to infinite warp friction moment with a moderate to low damping force.
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