发明名称 |
Marker for locating a buried object |
摘要 |
A marker for positioning near a buried object wherein the marker can be detected to locate the buried object. The marker includes a passive resonant type antenna which becomes inoperative when the initial position for the buried marker is changed. A lead wire and/or a mercury switch that is a part of the antenna serve to make the antenna inoperative due to such change in the initial position of the marker.
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申请公布号 |
US4873533(A) |
申请公布日期 |
1989.10.10 |
申请号 |
US19870106343 |
申请日期 |
1987.10.09 |
申请人 |
MINNESOTA MINING AND MANUFACTURING COMPANY |
发明人 |
OIKE, TOMOYASU |
分类号 |
G09F19/22;F16L1/024;G01S13/82;G01V3/00;G01V3/12;G01V15/00 |
主分类号 |
G09F19/22 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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