US3686479A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Static reader system for magnetic cards
Assignee: Rusco Industries Inc
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Filing: 1971-05-17
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Granted: 1972-08-22
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Expires: 1991-05-17
Abstract
Abstract A plurality of parallel electromagnetic sensors extend from one wall of a housing, and a card is slidably inserted between the opposite wall and the remaining ends of the sensors so that magnetic spots in the card have their fields coaxially aligned with the sensors. Each sensor has a core of high initial permeability that is substantially saturated by the card spot aligned therewith. The coils of the sensors are pulsed for reading data in the card, and are included in a system which utilizes the aiding and opposing relations of the fields of the coils and card spots to develop binary logic signals. Different arrangements are shown for exciting the coils serially and in parallel, and for establishing binary logic signals by magnitude or phase detection.
Inventors
- 👤 Waldo I Rogers
- 👤 Denis L Van Pelt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:26
CPC Classifications
G; G06; G06K; G06K7/00; G06K7/08; G06K7/082; G06K7/087
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
128 words
In combination: an assembly of parallel electromagnetic sensors, each having a coil surrounding a core that has high initial permeability and high flux density at saturation; means to support a magnetic card having a plurality of magnetized spots, wherein respective card spots and sensors are aligned; means for applying a voltage pulse to each coil to energize it, the voltage across any such coil having one characteristic where the coil and spot fields are in aiding relation, and another characteristic where the coil and spot fields are in opposing relation; and logic circuit means developing a respective binary logic level output from the voltage across each coil, wherein the logic level is low if the voltage has one characteristic and high if the voltage has the other characteristic.
Claim 2
Dependent Claim
128 words
In combination: an assembly of parallel electromagnetic sensors, each having a coil surrounding a core that has high initial permeability and high flux density at saturation; means to support a magnetic card having a plurality of magnetized spots, wherein respective card spots and sensors are aligned; means for applying a voltage pulse to each coil to energize it, the voltage across any such coil having one characteristic where the coil and spot fields are in aiding relation, and another characteristic where the coil and spot fields are in opposing relation; and logic circuit means developing a respective binary logic level output from the voltage across each coil, wherein the logic level is low if the voltage has one characteristic and high if the voltage has the other characteristic.
Claim 3
Dependent Claim
59 words
The combination of claim 1, wherein the circuit means has an operational threshold, and wherein, a predetermined time after a pulse is applied to a coil, the voltage across the coil is below such threshold if the coil and spot fields are in aiding relation, and above such threshold if the coil and spot fields are in opposing relation.
Claim 4
Dependent Claim
46 words
The combination of claim 2, wherein the circuit means has an operation threshold, and wherein, a predetermined time after a pulse is applied to a coil, the voltage across the coil is above such threshold only if the coil and spot fields are in opposing relation.
Claim 5
Dependent Claim
16 words
The combination of claim 1, including means to simultaneously apply a voltage pulse to all coils.
Claim 6
Dependent Claim
23 words
The combination of claim 1, including means to apply a voltage pulse to one coil at a time, and in a predetermined sequence.
Claim 7
Dependent Claim
22 words
The combination of claim 1, including means to sequentially apply a voltage pulse simultaneously to the coils of different groups of coils.
Claim 8
Dependent Claim
102 words
The combination of claim 4, including a respective resistor connected in series with each coil, said series connected resistors and coils being connected in parallel, the voltage pulse being applied across each series connected resistor and coil; respective logic circuits in said circuit means having inputs connected to respective resistor-coil junctions, each logic circut having a gate input and output; a delayed pulse generator connected to said gate inputs and operable by the voltage pulse to apply a pulse to said gate inputs at said predetermined time; and output network means having respective input connections from the outputs of said logic circuits.
Claim 9
Dependent Claim
80 words
The combination of claim 5, wherein said circuit means has a level input, connected to said coils, a gate input, and a level output; current limiting means connected to said coils; means for selectively applying a voltage pulse to each coil; a delayed pulse generator, said generator being connected to said gate input and operable by each voltage pulse to appLy a pulse to said gate input at said predetermined time; and output network means connected to said level output.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-22 | 1976-02-21 | 1976-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-22 | 1980-02-21 | 1980-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-22 | 1984-02-21 | 1984-08-22 | $7700.00 | Window Closed / Lapsed |