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US4028567A Expired / Lapsed US ⏱️ 0.0 years remaining

Electromagnetic vibration-detector device, in particular for anti-theft purposes

Assignee: Individual
•
Filing: 1976-04-09
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Granted: 1977-06-07
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Expires: 1996-04-09
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Abstract

Abstract The invention concerns an electromagnetic vibration-detector device, in particular for anti-theft, comprising a core which is displaceable in the interior of a winding, said core being secured to the free end of a vibrating blade which is rigidly secured at its other end, the device being characterized in that a thickness of cellular material is stuck on at least one of the faces of the blade, and the thickness of cellular material comprises on its free face a sheet of flexible material.

Inventors

  • 👤 Jean Maillot

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 06:57
CPC Classifications
B; B60; B60R; B60R25/00; B60R25/10; B60R25/1004; B60R25/1006; G; G08; G08B; G08B13/00; G08B13/16; G08B13/1654; H; H02; H02K; H02K35/00; H02K35/02

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 101 words
An electromagnetic vibration-detector device for anti-theft purposes, comprising a winding, a plunger core in the interior of the winding, a vibrating blade, means for fixing the core to the free end of the blade with the core extending into the winding and being free to vibrate with the blade, means for rigidly securing the other end of the vibrating blade relative to the winding, a thickness of cellular material, and means for securing the cellular material on at least one of the faces of the blade, said thickness of cellular material comprising on its free face a sheet of flexible material.
Claim 2
Dependent Claim 101 words
An electromagnetic vibration-detector device for anti-theft purposes, comprising a winding, a plunger core in the interior of the winding, a vibrating blade, means for fixing the core to the free end of the blade with the core extending into the winding and being free to vibrate with the blade, means for rigidly securing the other end of the vibrating blade relative to the winding, a thickness of cellular material, and means for securing the cellular material on at least one of the faces of the blade, said thickness of cellular material comprising on its free face a sheet of flexible material.
Claim 3
Dependent Claim 19 words
A device according to claim 1, characterised in that the cellular material comprises a thin sheet of synthetic foam.
Claim 4
Dependent Claim 20 words
A device according to claim 1, characterised in that the sheet of flexible material is a sheet of synthetic material.
Claim 5
Dependent Claim 27 words
A device according to claim 1, characterised in that the core comprises, in its part which is disposed within the winding, a rod provided with surface unevenness.
Claim 6
Dependent Claim 22 words
A device according to claim 4, characterised in that the rod is of a conical configuration at its connection to the blade.
Claim 7
Dependent Claim 14 words
A device according to claim 4, characterised in that the rod comprises a screw.
Claim 8
Dependent Claim 49 words
A device according to claim 4, characterised in that the core comprises a magnet secured to the face of the blade which is remote from the winding, and a rod of magnetically permeable material which is fixed against the face of the blade that is directed towards the winding.
Claim 9
Dependent Claim 17 words
A device according to claim 7, characterised in that the blade is of a magnetically permeable material.

References Cited (Backward Citations)

US2478712A Cited
US2659857A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-06-06 1980-12-06 1981-06-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-06-06 1984-12-06 1985-06-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-06-06 1988-12-06 1989-06-07 $7700.00 Window Closed / Lapsed

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