US4196418A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Detection plate for an identification system
Assignee: Nederlandsche Apparatenfabriek NEDAP NV
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Filing: 1977-10-31
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Granted: 1980-04-01
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Expires: 1997-10-31
Abstract
Abstract A detection plate for an identification system, comprising a resonant circuit, a switching device, and coding means, characterized in that the coding means comprises a digital circuit and is arranged to receive, in operation, supply voltage from the resonant circuit via rectifier means.
Inventors
- 👤 Harm J. Kip
- 👤 Tallienco W. H. Fockens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:05
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/04; G05B19/12; A; A01; A01K; A01K11/00; A01K11/006; B; B61; B61L; B61L25/00; B61L25/02; B61L25/04; B61L25/043; G01; G01S; G01S13/00; G01S13/74; G01S13/75; G01S13/751; G01S13/758; G06; G06K; G06K19/00; G06K19/06; G06K19/067; G06K19/07; G06K19/0723; G07; G07C; G07C9/00; G07C9/20; G07C9/28; G08; G08G; G08G1/00; G08G1/01; G08G1/017
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
117 words
A detection plate for an identification system, comprising a resonant circuit, a switching device, a coding means, and a separate pulse generator fed by the resonant circuit, the output of said pulse generator being connected to the coding means characterized in that the coding means comprises a digital circuit containing at least one preselected code and is arranged to receive, in operation, both a supply voltage from the resonant circuit via rectifier means and control pulses from said separate pulse generator which are processed by said coding means for providing output signals according to said at least one preselected code, said output signals being fed to said switching device for affecting the resonance of said resonant circuit.
Claim 2
Dependent Claim
117 words
A detection plate for an identification system, comprising a resonant circuit, a switching device, a coding means, and a separate pulse generator fed by the resonant circuit, the output of said pulse generator being connected to the coding means characterized in that the coding means comprises a digital circuit containing at least one preselected code and is arranged to receive, in operation, both a supply voltage from the resonant circuit via rectifier means and control pulses from said separate pulse generator which are processed by said coding means for providing output signals according to said at least one preselected code, said output signals being fed to said switching device for affecting the resonance of said resonant circuit.
Claim 3
Dependent Claim
92 words
A detection plate according to claim 1 wherein said coding means comprises a digital counter and further comprising at least one digital multiplex circuit wherein the ouputs of the counter are connected to the control inputs of said at least one digital multiplex circuit, which further comprises a plurality of adjustable coding inputs and an output connected to control the switching means and wherein the control pulses are processed in said at least one digital multiplex circuit into said at least one preselected code signal that is supplied to the switching means.
Claim 4
Dependent Claim
35 words
A detection plate according to claim 2, wherein one output of the counter is connected to the coding inputs of each multiplex circuit to form periodic intervals during which the switching means is not energized.
Claim 5
Dependent Claim
72 words
A detection plate according to claim 2, wherein said at least one digital multiplex circuit comprises first and second digital multiplex circuits and one output signal from the counter is supplied direct to a control input of said first multiplex circuit and, a signal invertor connected to feed said one output signal to a control input of said second multiplex circuit, in order to cause the multiplex circuits to be alternately operative.
Claim 6
Dependent Claim
44 words
A detection plate according to claim 1, wherein the switching device is connected to said resonant circuit so as to selectively short circuit said resonant circuit upon the occurrence of the output signals from the coding means, thereby preventing said resonant circuit from resonating.
Claim 7
Dependent Claim
43 words
A detection circuit according to claim 1, further comprising an inductor connected to said resonant circuit and said switching means, whereby said switching means detunes the resonant circuit under the control of the coding means by connecting said inductor to the resonant circuit.
Claim 8
Dependent Claim
42 words
A detection plate according to claim 1, further comprising a non-linear element connected to said resonant circuit and said switching means whereby said non-linear element is connected to the resonant circuit by said switching means under the control of the coding means.
Claim 9
Dependent Claim
43 words
A detection circuit according to claim 1, further comprising a capacitor connected to said resonant circuit and said switching means, whereby said switching means detunes the resonant circuit under the control of the coding means by connecting said capacitor to the resonant circuit.
References Cited (Backward Citations)
US3299424A
Cited
US3701150A
Cited
US3745569A
Cited
US3859624A
Cited
US4087791A
Cited
US3964024A
Cited
US3981011A
Cited
US4129855A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-04-01 | 1983-10-01 | 1984-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-04-01 | 1987-10-01 | 1988-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-04-01 | 1991-10-01 | 1992-04-01 | $7700.00 | Window Closed / Lapsed |