Boring or penetrating the earth – Bit or bit element – Rolling cutter bit or rolling cutter bit element
Reexamination Certificate
2005-08-23
2005-08-23
Tsay, Frank S. (Department: 3672)
Boring or penetrating the earth
Bit or bit element
Rolling cutter bit or rolling cutter bit element
C175S393000
Reexamination Certificate
active
06932171
ABSTRACT:
A ground drilling machine comprises a controller for automatically controlling the injection of working liquid according to the output signal output as a function of the rotating condition of the pilot head20. When the pilot head20is driven forward or backward, working liquid can be injected by switching the working liquid transfer valve111so long as the pilot head20is revolving in order to improve the digging efficiency, the soil delivering efficiency and the cooling efficiency of the machine. The injection of working liquid can be suspended when the direction of propelling the pilot head20is shifted while stopping the revolution of the pilot head20because no working liquid is required for delivering the dug soil and cooling the leading body. Thus, working liquid can be injected always at an optimal rate depending on the rotating condition of the pilot head20to suppress any waste of working liquid and reduce the construction cost.
REFERENCES:
patent: 3576222 (1971-04-01), Acheson et al.
patent: 4673045 (1987-06-01), McCullough
patent: 4930586 (1990-06-01), Turin et al.
patent: 4991667 (1991-02-01), Wilkes et al.
patent: 5148880 (1992-09-01), Lee et al.
patent: 5651420 (1997-07-01), Tibbitts et al.
patent: 6142246 (2000-11-01), Dickinson et al.
patent: 6386300 (2002-05-01), Curlett et al.
Muramoto Ei-ichi
Watanabe Kentaro
Yamazaki Kazuyuki
Youan Toyohiko
Frishauf Holtz Goodman & Chick P.C.
Komatsu Ltd.
Tsay Frank S.
LandOfFree
Ground drilling machine does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ground drilling machine, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ground drilling machine will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3456169