Appeal No. 1997-1190
Application No. 08/427,972
The location of interaction between the drillstem 20
and the wellbore casing 22 or other downhole structure
may be determined by measuring torsional vibrations and
axial vibrations which exhibit a particular phase
relationship. The actual location downhole of the
interaction between the drillstem and the casing, for
example, can be determined using the parameters including
longitudinal and torsional wave speed in steel . . . The
time difference between the arrival of an axial wave peak
at the surface as measured by the strain gages 62 and 64
[mounted on sub 36] as compared with the arrival of a
torsional wave peak as measured by the torque strain
gages 74 and 76 [mounted on sub 38] can be used to
determine the location of the casing-drillstem
interaction since the longitudinal wave speed and
torsional wave speed can be calculated for a particular
material such as steel wherein the modulus of elasticity
and the density of the material are known. (Col. 6,
lines 48-67).
It is the examiner's position that the above quoted
passages in Bseisu describe a "process of synchronization,
since it is anticipated that such correlation of measurements
should have included correlation of at least two sets of
signals both in the same phase and time intervals"
(supplemental answer, pages 10 and 11).
In our opinion, the examiner's interpretation of the
reference is speculative at best. We find no specific
teaching in Bseisu that the correlation of signal analysis
relied on by the examiner involves the synchronized
acquisition of measurement signals as called for in claims 1
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