Title:
SHAFT SINKING MACHINE
Document Type and Number:
Japanese Patent JP2989350
Kind Code:
B2
Abstract:
PURPOSE: To provide a shaft sinking machine capable of obtaining sufficient directional corrective force in addition to be capable of performing earth cutting in a manner, while it is only enough to set the extent of strength in a drill pipe to that taking account of earth removal and drill bit rotation, leading to a reduction in cost.
CONSTITUTION: Operating a rotational driver 3, a drill pipe 2 and a ground cutting drill bit 1 are rotated, while a thrust is given to this drill bit 1 by each steering jack 10, thus earth cutting takes place. At this time, a relative displacement between the ground and the earth cutting drill bit 1 is detected by two displacement detectors 11 and 12, transmitting a displacement detecting signal to be secured at that time to a thrust controller of the steering jacket 10. With the control signal secured here, the thrust of each steering jack 10 is controlled, and further the thrust of the drill bit 1 and the drilling direction are controlled as well.
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Inventors:
OKU KOREHIKO
SASAKI KYOMI
SASAKI KYOMI
Application Number:
JP30492791A
Publication Date:
December 13, 1999
Filing Date:
November 20, 1991
Export Citation:
Assignee:
MITSUBISHI JUKOGYO KK
International Classes:
E21B3/04; E21B17/00; E21B47/02; (IPC1-7): E21B3/04; E21B17/00
Domestic Patent References:
| JP3140594A | ||||
| JP6033993A | ||||
| JP5948593A |
Attorney, Agent or Firm:
Koharu Fujita (3 outside)