Patent US4884973A successfully refreshed from Google Patents.
US4884973A
Expired / Lapsed
US
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Mathematic teaching aid
Assignee: Individual
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Filing: 1989-01-18
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Granted: 1989-12-05
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Expires: 2009-01-18
Abstract
Abstract An aid for teaching children addition and subtraction of two numbers according to an algebraic equation. Cards bearing selected integers and one card bearing a plus or minus sign are placed by the teacher on a panel in horizontally aligned spaces corresponding to the terms of the equation but for one space. The student is then challenged to hang a card displaying the appropriate integer or sign in the vacant space. Rings slidable on a horizontal rod are positionable in the spaces in quantities corresponding to the integers thereat for visual reinforcement of the equation.
Inventors
- 👤 Kyoungsik Pak
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:33
CPC Classifications
G; G09; G09B; G09B19/00; G09B19/02; G09B1/00; G09B1/02; G09B1/04; G09B1/06; G09B1/10
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
65 words
Apparatus for visually representing an algebraic equation comprising, in combination: a panel having a plurality of connectors aligned at positions corresponding to the terms of the equation, and bearing an equal sign between the penultimate and lastconnectors; and cards formed to engage selected ones of said connectors, at least one of saidcards bearing the sign of a mathematical operator and the remainder bearing discrete integers.
Claim 2
Dependent Claim
65 words
Apparatus for visually representing an algebraic equation comprising, in combination: a panel having a plurality of connectors aligned at positions corresponding to the terms of the equation, and bearing an equal sign between the penultimate and lastconnectors; and cards formed to engage selected ones of said connectors, at least one of saidcards bearing the sign of a mathematical operator and the remainder bearing discrete integers.
Claim 3
Dependent Claim
43 words
Apparatus according to claim 1 further comprising: a rod fixed to said panel adjacent to and coextensive with said connectors and members supported by said rod and manually slidable to positions along the length thereof corresponding to the integers displayed by said cards.
Claim 4
Dependent Claim
194 words
Apparatus for teaching addition and subtraction of two numbers represented by the equation, comprising, in combination: a panel having first, second, third and fourth connectors aligned at positions corresponding to A, + or -, B and C, respectively, of the equation and bearing an equal sign between said third and fourth connectors; a quantity of first cards formed to engage selected ones of said first, thirdand fourth connectors with either side hidden from view, each of said first cards bearing a discrete integer on one side from zero to the quantity and bearing a discrete integer from zero to the quantity on the other side different from the integer on the one side; and a second card formed to engage said second connector with either side hidden from view, said second card bearing a plus sign on one side and a minus sign on the other side; whereby display of any combination of two integers and one sign or of three integers of said cards at three of said connectors challenges a student to display an appropriate integer or sign of said cards at the remaining one of said connectors to complete the equation.
Claim 5
Dependent Claim
194 words
Apparatus for teaching addition and subtraction of two numbers represented by the equation, comprising, in combination: a panel having first, second, third and fourth connectors aligned at positions corresponding to A, + or -, B and C, respectively, of the equation and bearing an equal sign between said third and fourth connectors; a quantity of first cards formed to engage selected ones of said first, thirdand fourth connectors with either side hidden from view, each of said first cards bearing a discrete integer on one side from zero to the quantity and bearing a discrete integer from zero to the quantity on the other side different from the integer on the one side; and a second card formed to engage said second connector with either side hidden from view, said second card bearing a plus sign on one side and a minus sign on the other side; whereby display of any combination of two integers and one sign or of three integers of said cards at three of said connectors challenges a student to display an appropriate integer or sign of said cards at the remaining one of said connectors to complete the equation.
Claim 6
Dependent Claim
74 words
Apparatus according to claim 1 further comprising: a rod fixed to said panel adjacent to and coextensive with said connectors; and a quantity of rings supported said rod and manually slidable along the thereof, the quantity of said rings being equal to the quantity of said first cards; whereby said rings can be positioned along the length of said rod in numbers corresponding to the integers displayed at said first, third and fourth connectors.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-12-04 | 1993-06-05 | 1993-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-12-04 | 1997-06-05 | 1997-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-12-04 | 2001-06-05 | 2001-12-05 | $7700.00 | Window Closed / Lapsed |