Patent NL8903200A successfully refreshed from Google Patents.
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
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
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
NL
Data Source
google_patents
Last Synchronized
2026-11-08 18:26
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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