Appeal No. 95-1276
Application 07/839,969
art applied by the examiner, and the respective positions
advanced by appellants in the brief and the examiner in the
answer. As a consequence of this review, we conclude that the
rejections of the examiner should not be sustained.
Independent claim 80 calls for, inter alia, the step of
receiving, at a location on the drill collar, acoustic energy
returned from the surrounding earth formations.
Considering first the rejection based on the use of
Lygas as the primary reference, Lygas discloses a method for
performing logging while drilling a borehole traversing an earth
formation, including drilling the borehole with a drill string 13
having a drill bit 14 at its lower end and drilling fluid in the
borehole surrounding the drill string (Fig. 1; Col. 1, lines 15-
18; Col. 3, lines 22-25; Col. 8, line 19). The method steps
include drilling with a data handling sub 15 incorporated into
the drill string 13. Lygas also discloses that the acoustic
signals penetrate the walls of the borehole and enable analysis
of sub-terranian formations ahead of the bit and thus at least
suggest the presence of a receiver (Col. 1, lines 15-28).
However, Lygas is silent about the location of a receiver.
The examiner states that measurement of formations
ahead of the drill bit is usually accomplished by keeping the
4
Page: Previous 1 2 3 4 5 6 7 8 9 Next
Last modified: November 3, 2007