Appeal No. 1997-2340 Page 5
Application No. 08/329,687
overturned. In re Fine, 837 F.2d 1071, 1074, 5
USPQ2d 1596, 1598 (Fed. Cir. 1988).
With these principles in mind, we address the examiner's
rejection and the appellant's argument.
The examiner's rejection follows in pertinent part.
The prior art figure does not show a detect means
for detecting the voltage or current of the
switching thyristors in order to send a firing pulse
to all of the switching elements to protect the
thyristor(s) which is(are) conductive.
Takahashi shows in figure 1 series connected
thyristors 1N, 12, 13 with a voltage detect circuit
in parallel to each thyristor (4N ... 41) and a
digital circuit for combining and comparing the
voltage sense responses for determining an out of
range voltage for any of the individual thyristors
an sending a signal h to simultaneously fire all of
the thyristors into conduction to avoid an
application of overvoltages across some of the
thyristors.
Mitsuoka shows in figure 5 a current sensor 13
for measuring the current through the thyristor 1
and parallel components for detecting an abnormal
signal, causing the conduction of the thyristor lla
and llb to protect the thyristor 1.
(Paper No. 16 at 3.) The appellant argues, "the prior art
does not disclose or suggest the claimed detecting of self-
firing." (Appeal Br. at 7.)
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