Vibration-sensitive transducer
First Claim
1. A cable type transducer in the form of an elongate cable for producing electrical signals in response to a mechanical vibration or impulse of the cable at any point along the cable comprising an elongate structure comprising elongate flexible magnetic flux generating means extending continuously longitudinally of said elongate structure, an electrical conductor and support means for supporting said electrical conductor so that it extends substantially longitudinally of the elongate structure and is loosely constrained laterally of the structure within the magnetic field generated by the magnetic flux generating means to allow limited movement of the electrical conductor relative to magnetic field generated by the magnetic flux generating means so that the said electrical conductor is movable in response to mechanical disturbance of the cable at any point along the cable, relative to the magnetic field generated by the magnetic flux generating means, so that the movement induces an e.m.f. in the electrical conductor thereby producing said electrical signals.
2 Assignments
0 Petitions
Accused Products
Abstract
A transducer in the form of a long cable for producing electrical signals in response to mechanical vibration of the cable. The cable comprises an elongate magnetic member and an electrical conductor extending alongside the magnetic member, the electrical conductor being loosely mounted in the magnetic field of the magnetic member so that mechanical vibration of the cable causes the electrical conductor to move relative to the magnetic field whereby an e.m.f. and hence an electrical signal is induced in the conductor. The transducer may be used in monitoring or security apparatus.
23 Citations
21 Claims
- 1. A cable type transducer in the form of an elongate cable for producing electrical signals in response to a mechanical vibration or impulse of the cable at any point along the cable comprising an elongate structure comprising elongate flexible magnetic flux generating means extending continuously longitudinally of said elongate structure, an electrical conductor and support means for supporting said electrical conductor so that it extends substantially longitudinally of the elongate structure and is loosely constrained laterally of the structure within the magnetic field generated by the magnetic flux generating means to allow limited movement of the electrical conductor relative to magnetic field generated by the magnetic flux generating means so that the said electrical conductor is movable in response to mechanical disturbance of the cable at any point along the cable, relative to the magnetic field generated by the magnetic flux generating means, so that the movement induces an e.m.f. in the electrical conductor thereby producing said electrical signals.
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10. A cable type transducer for producing electrical signals in response to a mechanical vibration or impulse comprising an elongate structure comprising elongate magnetic flux generating means and an electrical conductor, the electrical conductor being loosely retained alongside the magnetic flux generating means within the magnetic field generated thereby so that the said electrical conductor is movable in response to mechanical disturbance of the cable, relative to the magnetic flux generating means, so that the movement induces an e.m.f. in the electrical conductor thereby producing said electrical signals and wherein the magnetic flux generating means constitutes an additional electrical conductor and the first mentioned electrical conductor and the magnetic flux generating means are electrically connected so as to provide a differential output.
- 11. A cable type transducer for producing electrical signals in response to a mechanical vibration or impulse comprising an elongate structure comprising elongate magnetic flux generating means and an electrical conductor, the electrical conductor being loosely retained alongside the magnetic flux generating means within the magnetic field generated thereby so that the said electrical conductor is movable in response to mechanical disturbance of the cable, relative to the magnetic flux generating means, so that the movement induces an e.m.f. in the electrical conductor thereby producing said electrical signals, the transducer further comprising a cylindrical core having a longitudinally extending slot defined therein, and wherein the said electrical conductor is located in the slot in the periphery of the cylindrical core.
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16. A cable type transducer in the form of an elongate cable for producing electrical signals in response to a mechanical vibration or impulse of the cable at any point along the cable comprising an elongate structure comprising elongate flexible magnetic flux generating means extending continuously longitudinally of said elongate structure and formed by a tape of permanently magnetized material parallel to its width in the same direction over its enire length, an electrical conductor and support means for supporting said electrical conductor so that it extends substantially longitudinally of the elongate structure and is loosely retained alongside the edges of the tape of magnetic flux generating means adjacent a pole of the magnetic flux generating means within the magnetic field generated thereby to allow limited movement of the electrical conductor relative to the magnetic field generated by the magnetic flux generating means so that the said electrical conductor is movable in response to mechanical disturbance of the cable, relative to the magnetic field generated to the magnetic flux generating means, so that the movement induces an e.m.f. in the electrical conductor thereby producing said electrical signals, the support means comprising a hollow sheath extending alongside said magnetic flux generating means and said electrical conductor comprising a wire loosely fitting into said sheath, said wire having an external diameter smaller than an internal diameter of said hollow sheath and wherein said electrical conductor is constituted by at least one run of said wire lengthwise of the cable.
- 17. A cable type transducer for producing electrical signals in response to a mechanical vibration or impulse comprising an elongate structure comprising elongate magnetic flux generating means and an electrical conductor, the electrical conductor being loosely retained within the magnetic field generated by the magnetic flux generating means so that the said electrical conductor is movable in response to mechanical disturbance of the cable, relative to the magnetic flux generating means, so that the movement induces an e.m.f. in the electrical conductor thereby producing said electrical signals, the transducer further comprising a core conforming generally to a cylindrical surface and having means defining at least one slot portion extending longitudinally of the core and radially inwardly of said cylindrical surface and in which slot portion is located said loosely retained electrical conductor.
Specification