US3720006A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Teaching apparatus
Assignee: Individual
•
Filing: 1971-01-19
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Granted: 1973-03-13
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Expires: 1991-01-19
Abstract
Abstract A teaching apparatus comprising a printed sheet carrying questions and for each question a number of demarked areas denoting different answers, a platen locatable behind the sheet and bearing a plurality of separate electrically conductive areas registrable with the sheet demarked areas, a probe in circuit with the conductive areas and connectable to an electric energy source, and a multivibrator for applying to the conductive areas at will periodically time-varying signals separable to a receiver T1 and capable of causing from the conductive areas radiation of corresponding electromagnetic waves capable of being sensed in front of the sheet by the probe touching the sheet, the receiver T1 being coupled to the probe to identify the wave picked up thereby and actuating indicating means indicating the correctness of the selected answer.
Inventors
- 👤 F Boram
- 👤 D Kail
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:56
CPC Classifications
G; G09; G09B; G09B7/00; G09B7/06; G09B7/063
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
268 words
A teaching apparatus comprising, in combination: a printed sheet having at least one question thereon and at least a pair of demarked areas each denoting a different answer to said question; a platen locatable in substantial registry with said sheet and on one side thereof; at least a pair of electrically conductive areas on said platen each of said conductive areas being in juxtaposition with each of said demarked areas, respectively, when said platen is in registry with said sheet; means for energizing one of said conductive areas to radiate time-varying electromagnetic energy of one phase, and means for energizing the other of said conductive areas to radiate timevarying electromagnetic energy of a second phase, whereby the energy radiated by said one conductive area is out of phase with respect to the energy radiated by said other conductive area, said conductive areas being separated sufficiently to prevent ambiguity of radiated energy at said demarked areas; pick up means selectively positionable adjacent either of said demarked areas on the opposite side of said sheet for receiving the electromagnetic energy radiated therethrough and including output means for producing a time-varying electrical signal corresponding in phase with the electromagnetic energy received; plural indicator means for indicating the correctness of the answer corresponding to the possible different answers to said question; phase comparison means connected to said output means of said pick up means for energizing said indicator means according to the positioning of said pick up means relative to one of said answer areas, whereby the electromagnetic energy radiated and its respective phase determines which of said indicator means is activated.
Claim 2
Dependent Claim
268 words
A teaching apparatus comprising, in combination: a printed sheet having at least one question thereon and at least a pair of demarked areas each denoting a different answer to said question; a platen locatable in substantial registry with said sheet and on one side thereof; at least a pair of electrically conductive areas on said platen each of said conductive areas being in juxtaposition with each of said demarked areas, respectively, when said platen is in registry with said sheet; means for energizing one of said conductive areas to radiate time-varying electromagnetic energy of one phase, and means for energizing the other of said conductive areas to radiate timevarying electromagnetic energy of a second phase, whereby the energy radiated by said one conductive area is out of phase with respect to the energy radiated by said other conductive area, said conductive areas being separated sufficiently to prevent ambiguity of radiated energy at said demarked areas; pick up means selectively positionable adjacent either of said demarked areas on the opposite side of said sheet for receiving the electromagnetic energy radiated therethrough and including output means for producing a time-varying electrical signal corresponding in phase with the electromagnetic energy received; plural indicator means for indicating the correctness of the answer corresponding to the possible different answers to said question; phase comparison means connected to said output means of said pick up means for energizing said indicator means according to the positioning of said pick up means relative to one of said answer areas, whereby the electromagnetic energy radiated and its respective phase determines which of said indicator means is activated.
Claim 3
Dependent Claim
268 words
A teaching apparatus comprising, in combination: a printed sheet having at least one question thereon and at least a pair of demarked areas each denoting a different answer to said question; a platen locatable in substantial registry with said sheet and on one side thereof; at least a pair of electrically conductive areas on said platen each of said conductive areas being in juxtaposition with each of said demarked areas, respectively, when said platen is in registry with said sheet; means for energizing one of said conductive areas to radiate time-varying electromagnetic energy of one phase, and means for energizing the other of said conductive areas to radiate time-varying electromagnetic energy of a second phase, whereby the energy radiated by said one conductive area is out of phase with respect to the energy radiated by said other conductive area, said conductive areas being separated sufficiently to prevent ambiguity of radiated energy at said demarked areas; pick up means selectively positionable adjacent either of said demarked areas on the opposite side of said sheet for receiving the electromagnetic energy radiated therethrough and including output means for producing a time-varying electrical signal corresponding in phase with the electromagnetic energy received; plural indicator means for indicating the correctness of the answer corresponding to the possible different answers to said question; phase comparison means connected to said output means of said pick up means for energizing said indicator means according to the positioning of said pick up means relative to one of said answer areas, whereby the electromagnetic energy radiated and its respective phase determines which of said indicator means is activated.
Claim 4
Dependent Claim
268 words
A teaching apparatus comprising, in combination: a printed sheet having at least one question thereon and at least a pair of demarked areas each denoting a different answer to said question; a platen locatable in substantial registry with said sheet and on one side thereof; at least a pair of electrically conductive areas on said platen each of said conductive areas being in juxtaposition with each of said demarked areas, respectively, when said platen is in registry with said sheet; means for energizing one of said conductive areas to radiate time-varying electromagnetic energy of one phase, and means for energizing the other of said conductive areas to radiate time-varying electromagnetic energy of a second phase, whereby the energy radiated by said one conductive area is out of phase with respect to the energy radiated by said other conductive area, said conductive areas being separated sufficiently to prevent ambiguity of radiated energy at said demarked areas; pick up means selectively positionable adjacent either of said demarked areas on the opposite side of said sheet for receiving the electromagnetic energy radiated therethrough and including output means for producing a time-varying electrical signal corresponding in phase with the electromagnetic energy received; plural indicator means for indicating the correctness of the answer corresponding to the possible different answers to said question; phase comparison means connected to said output means of said pick up means for energizing said indicator means according to the positioning of said pick up means relative to one of said answer areas, whereby the electromagnetic energy radiated and its respective phase determines which of said indicator means is activated.
Claim 5
Dependent Claim
29 words
A teaching apparatus as defined in claim 1 wherein said means for energizing includes a multivibrator having a pair of phase-opposed outputs connected respectively to said two conductive areas.
Claim 6
Dependent Claim
25 words
A teaching apparatus according to claim 2 wherein one output of said multivibrator is coupled to said phase comparison means to provide phase reference thereto.
Claim 7
Dependent Claim
90 words
A teaching apparatus as defined in claim 3 wherein said phase comparison means includes a switch for each indicator means, a field effect transistor coupled to the output of said pick up means to provide a signal in phase with the output of said pick up means and a signal in phase opposition with the output of said pick up means, one of said signals being coupled to the switch associated with one indicator means and the other signal being coupled to the switch associated with the other indicator means.
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) | 1976-03-12 | 1976-09-11 | 1977-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-12 | 1980-09-11 | 1981-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-12 | 1984-09-11 | 1985-03-13 | $7700.00 | Window Closed / Lapsed |