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AssigneeKabushiki Kaisha Komatsu Seisakusho
InventorsHiroaki Yamaguchi, Shuji Arakawa, Tomoyuki Abe, Yasuhiko Ichimura, Yasuo Kanemitsu
Estimating the term…
Magnetic field producers are disposed either at the leading portion of an underground excavator or at a reference position in front of the underground excavator. The magnetic field producers can be constituted by a plurality of rectangular loops disposed to run parallel to one another and to overlap one another. The rectangular loops can be individually excited sequentially or they can be simultaneously excited at different frequencies. The magnetic field produced by a magnetic field producer can be detected by a first magnetic field detector and by a second magnetic field detector disposed to the rear of the first magnetic field detector so that the inclination angle of the underground excavator can be obtained from the difference between the positions of the two detectors. A loop of a magnetic field producing cable can be covered by a non-magnetic metal member so that wear and disconnection are prevented. A double loop structure can be employed so that measurement can be performed even if one of the loops is disconnected.
An apparatus for detecting the position of an underground excavator comprising:
An apparatus for detecting the position of an underground excavator comprising:
A magnetic field producing apparatus for detecting the position of an underground excavator which acts to establish a connection under the group, comprising said underground excavator, and a magnetic field producing cable attached to the front surface of said underground excavator, said magnetic field producing cable being covered with a non-magnetic metal cover so that wear and disconnection of the magnetic field producing cable can be prevented while reducing any restriction of the magnetic field intensity in the forward direction from the underground excavator.
A magnetic field producing apparatus for detecting the position of an underground excavator comprising said underground excavator, and on the front surface of said underground excavator, a first rectangular loop and a second rectangular loop for producing symmetric magnetic fields in the forward direction which are respectively perpendicular to said front surface, wherein said second rectangular loop is disposed at a position to the rear of said first rectangular loop, and wherein said first and second rectangular loops are independently supplied with electric currents.
Dependencies are inferred from the claim text.