Patent US4108498A successfully refreshed from Google Patents.
US4968258A
Expired / Lapsed
US
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Reusable learning aid
Assignee: TRACE ERASE LLC
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Filing: 1989-09-01
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Granted: 1990-11-06
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Expires: 2009-09-01
Abstract
Abstract A learning aid permitting the student to insert a worksheet into a rigid body having space between two planes. One of the plaens is clear permitting the instructor to mark on it, performing the work demanded by the underlying worksheet. The instructor's marking is erased and the student attempts the same task. The work sheet is secured in place either by (i) its natural mechanical tension with the two planes, or (ii) by an insert mechanism securing the paper either through electrical attraction or by a mechanical clip.
Inventors
- 👤 Max O. Kees
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:34
CPC Classifications
G; G09; G09B; G09B3/00; G09B3/06; G09B3/08
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
118 words
A reusable learning aid comprising: (a) a first rigid layer having four edges and being transparent, said first layer accepting markings thereon and erasure therefrom; (b) a second rigid layer substantially the same shape and size as said first layer; (c) spacing means positioned around a portion of the periphery of said first layer for maintaining said first layer and said second layer in a fixed spaced apart relationship and for creating an air pocket therebetween; and, (d) an insert mechanism for insertion thereof between said first layer and said second layer by an operator, said insert mechanism having means for securing a sheet of paper thereto including means for establishing an electrical charge on said insert mechanism.
Claim 2
Dependent Claim
118 words
A reusable learning aid comprising: (a) a first rigid layer having four edges and being transparent, said first layer accepting markings thereon and erasure therefrom; (b) a second rigid layer substantially the same shape and size as said first layer; (c) spacing means positioned around a portion of the periphery of said first layer for maintaining said first layer and said second layer in a fixed spaced apart relationship and for creating an air pocket therebetween; and, (d) an insert mechanism for insertion thereof between said first layer and said second layer by an operator, said insert mechanism having means for securing a sheet of paper thereto including means for establishing an electrical charge on said insert mechanism.
Claim 3
Dependent Claim
21 words
The reusable learning aid according to claim 1 wherein said means for establishing an electrical charge is introduced by said operator.
Claim 4
Dependent Claim
111 words
A study mechanism comprising: (a) a first rigid layer being substantially rectangular in shape and composed of a clear material permitting the writing and erasure thereon; (b) a second rigid layer being substantially rectangular in shape; (c) spacing means for securing said first layer substantially parallel to said second layer in spaced apart relationship; (d) an insert mechanism being susceptible to operator insertion between said first layer and said second layer and having a first side and a second side and means for securing a sheet of paper to the first side of said insert mechanism including means for placing an electrical charge on the first side of said insert mechanism.
Claim 5
Dependent Claim
111 words
A study mechanism comprising: (a) a first rigid layer being substantially rectangular in shape and composed of a clear material permitting the writing and erasure thereon; (b) a second rigid layer being substantially rectangular in shape; (c) spacing means for securing said first layer substantially parallel to said second layer in spaced apart relationship; (d) an insert mechanism being susceptible to operator insertion between said first layer and said second layer and having a first side and a second side and means for securing a sheet of paper to the first side of said insert mechanism including means for placing an electrical charge on the first side of said insert mechanism.
Claim 6
Dependent Claim
24 words
The study mechanism according to claim 3 wherein said means for placing an electrical charge includes means for operator introduction of said electrical charge.
Claim 7
Dependent Claim
151 words
An assemblage for the assistance of study comprising: (a) a learning aid having, (1) a first layer being substantially rectangular in shape and composed of a clear material permitting the writing and erasure thereon, (2) a second layer being substantially rectangular in shape, (3) spacing means for securing said first layer substantially parallel to said second layer in spaced apart relationship; (b) an insert mechanism being operator insertable between said first layer and said second layer of said learning aid, said insert mechanism having a first side and a second side and means for securing a sheet of paper to the first side thereof including means for placing an electrical charge in said first side of said insert mechanism; (c) at least one writing instrument for marking on said first layer; and, (d) a carrying case for holding said learning aid, said insert mechanism, and said at least one writing instrument.
Claim 8
Dependent Claim
151 words
An assemblage for the assistance of study comprising: (a) a learning aid having, (1) a first layer being substantially rectangular in shape and composed of a clear material permitting the writing and erasure thereon, (2) a second layer being substantially rectangular in shape, (3) spacing means for securing said first layer substantially parallel to said second layer in spaced apart relationship; (b) an insert mechanism being operator insertable between said first layer and said second layer of said learning aid, said insert mechanism having a first side and a second side and means for securing a sheet of paper to the first side thereof including means for placing an electrical charge in said first side of said insert mechanism; (c) at least one writing instrument for marking on said first layer; and, (d) a carrying case for holding said learning aid, said insert mechanism, and said at least one writing instrument.
Claim 9
Dependent Claim
20 words
The assemblage according to claim 5 further comprising means for erasing marks made by said at least one writing instrument.
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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) | 1993-11-05 | 1994-05-07 | 1994-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-05 | 1998-05-07 | 1998-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-05 | 2002-05-07 | 2002-11-06 | $7700.00 | Window Closed / Lapsed |