Appeal No. 2003-2136 Page 8
Application No. 09/562,952
Rh prevents the volatilization consumption of Ir," col. 3, l. 66 - col. 4, l. 1, "[t]he addition
of Rh is most effective, mostly because Rh has a melting point of 1960°C. . . ." Col. 4,
ll. 1-2. Because Oshima '198 invites modifications and additions to the Ir-based alloy of
its chip, and Osamura discloses that an Ir-Rh alloy improves heat resistance and
consumption resistance, offers a high melting point, and prevents volatilizing, we are
persuaded that the references would have suggested forming a spark plug's firing tip
chip from an Ir-Rh alloy and using laser beam welding to bond the chip to a front end of
a center electrode.
2. Chip Area vis-á-vis Electrode Area
The examiner finds, "Oshima '98, figure 11, teaches a spark plug having a noble
metal chip welded on a flat end surface of the center electrode wherein . . . the center
electrode has a larger diameter than the noble metal chip" (Examiner's Answer at 3.)
The appellants argue, "[o]n the other hand, Oshima '69 mentions at column 8, lines 30-
34 that it is preferable not to provide a diameter difference, in order to attain a better
penetration of laser beams. " (Appeal Br. at 11.)
In addressing the point of contention, the Board conducts a two-step analysis.
First, we construe the representative claim to determine its scope. Second, we
determine whether the construed claim would have been obvious.
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Next
Last modified: November 3, 2007