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NL8903200A Expired / Lapsed NL ⏱️ 0.0 years remaining

EM mechanical, resonator detecting shop lifter - vibrates audibly when exposed to magnetic field

Assignee: Willem Lentink
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Filing: 1989-12-31
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Granted: —
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Expires: 2009-12-31
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Abstract

Abstract The application describes various forms of resonator, the common factor being that they are all magnetic circuits made up from pieces of two types (2, 3) of material. The two materials have differing magnetic characteristics and there are air gaps between the different pieces. One of the materials is a permanent magnet of such field strength that the internal field and externally induced field combine to cause a change in the length of the magnetic path through the resonator, with resultant vibration. The various types of resonator include toroids and transformers. @(25pp Dwg.No.1/5)@.

Inventors

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Bibliographic Details

Application Number —
Jurisdiction NL
Data Source google_patents
Last Synchronized 2026-11-08 17:36
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/22; G08B13/24; G08B13/2402; G08B13/2405; G08B13/2408; G08B13/2411; G08B13/2428; G08B13/2437; G08B13/2442; H; H03; H03H; H03H9/00; H03H9/22

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