Magnetic cores for saturable core measuring devices and methods of manufacturing such cores
First Claim
1. A magnetic core comprising a non-magnetic elongated support and a pair of coaxial coils constituted by strips of permeable magnetic material oppositely wound helically about said support along the length thereof, said coils terminating at opposite ends thereof in substantially circular core end surfaces that lie in respective planes that are substantially perpendicular to the length of said support.
4 Assignments
0 Petitions
Accused Products
Abstract
A magnetic core, for use in fluxgate magnetometers or gradiometers, for example, comprises a pair of coaxial coils constituted by strips of permeable magnetic material oppositely wound on a non-magnetic cylindrical tube. At each of their opposite ends, the coils terminate in planes perpendicular to the length of the tube. In the manufacture of a core, the strips at each end of the coils may be joined to each other to form a lap extending along the length of the tube. In one embodiment, strip portions extending beyond the respective planes, including a portion of each lap, are cut off and removed. In another embodiment, the entire lap at each end is removed after the strips at each end are welded to each other. By virtue of the core construction, the signal-to-noise ratio of saturable core measuring devices using the cores is substantially improved.
47 Citations
14 Claims
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1. A magnetic core comprising a non-magnetic elongated support and a pair of coaxial coils constituted by strips of permeable magnetic material oppositely wound helically about said support along the length thereof, said coils terminating at opposite ends thereof in substantially circular core end surfaces that lie in respective planes that are substantially perpendicular to the length of said support.
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2. A magnetic core according to claim 1, wherein said strips are interwoven.
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3. A magnetic core according to claim 1, wherein said coils are superposed.
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4. A magnetic core according to claim 1, wherein, at each of the opposite ends of said coils, the strips are joined to each other by a lap extending along the length of said support, the length of each lap being substantially less than the full width of the strips.
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5. A magnetic core according to claim 1, wherein, at each of the opposite ends of said coils, the strips are welded to each other.
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6. A magnetic core according to claim 5, wherein, at each of the opposite ends of said coils, the strips are welded to said support.
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7. A method of making a magnetic core, comprising oppositely helically winding a pair of strips of permeable magnetic material on a non-magnetic elongated support so as to form coaxial coils, and terminating said coils at opposite ends thereof in substantially circular core end surfaces that lie in respective planes that are substantially perpendicular to the length of said support.
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8. A method according to claim 7, wherein the strips are interwoven as they are oppositely wound.
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9. A method according to claim 7, wherein said coils are superposed as they are wound.
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10. A method according to claim 7, wherein said terminating comprises cutting off portions of said strips that extend beyond the respective planes.
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11. A method according to claim 10, wherein, prior to the cutting off of said strip portions, the strips, at each end of said coils, are joined to form a lap that extends along the length of said support, and wherein at least part of each lap is removed when said strip portions are cut off.
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12. A method according to claim 11, wherein all of the laps are removed.
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13. A method according to claim 12, wherein, at each of the opposite ends of said coils, the strips are welded to each other before removal of the laps.
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14. A method according to claim 12, wherein, at each of the opposite ends of said coils, the strips are welded to said support.
Specification