Appeal No. 2003-0558 4
Application No. 09/477,601
where Tf, Ti, Tc and Tmax are as defined above and p is the ratio of the number of teeth
on the ring gear 14 to the number of teeth on the sun gear 13 of the differential 10. The
term (p/(1+p))Ti of the above formula is the power distribution ratio between the front and
rear drives shafts when the center differential device 10 operates freely (i.e., when its
internal clutch 21 is in the released condition) and the term Tc of the formula is a variable
that represents the amount of torque additionally transferred to each of the front and rear
drive shafts as a result of partial or full engagement of the internal clutch 21. Control of Tc
in this way assures that the torque Tf supplied to the front wheels of the vehicle does not
exceed Tmax, which is the maximum torque that is considered to be appropriate to supply
to the front wheels of the vehicle (col. 15, lines 24-27).
In finding correspondence between the method and system of Taga and claims 1
and 9, the examiner appears to take the position (see final rejection, page 3) that col. 13,
lines 59-60 of Taga discloses a mode of operation and structure that correspond to the
comparing step of claim 1 and the comparator structure of claim 9. In addition, in
responding to arguments presented by appellant in the brief, the examiner seems to take
the position (answer, pages 4-5) that Taga compares the torque Tf on the front axle to the
determinative value Tmax, and that this act reads on the comparing step of claim 1 (and
presumably the comparator structure of claim 9). For the reasons that follow, we cannot
accept these positions.
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