Patent US3123548A successfully refreshed from Google Patents.
Patent US5156475A successfully refreshed from Google Patents.
US5156475A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Keyboard divided by central inverted T-shaped entry-space key
Assignee: Individual
•
Filing: 1990-12-06
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Granted: 1992-10-20
•
Expires: 2010-12-06
Abstract
Abstract A keyboard comprises a plurality of regular keys, and an inverted T-shaped key subdividing the regular keys into two sections including one section for preferably left-hand operation and another section preferably for right-hand operation. A keyboard further comprises a trackball and/or two rollers requiring minimal hand movement in using them for mouse emulation.
Inventors
- 👤 Arkady Zilberman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:50
CPC Classifications
G; G06; G06F; G06F3/00; G06F3/01; G06F3/02; G06F3/0202; G06F3/0219; B; B41; B41J; B41J5/00; B41J5/08; B41J5/10; G06F3/021; G06F3/0213
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
49 words
A keyboard, comprising a plurality of regular keys; and an inverted T-shaped key located in a middle of the keyboard, having a `Space` and an `Enter` function, and subdividing said regular keys into two sections including one section for preferably left-hand operation and another section preferably for right-hand operation.
Claim 2
Dependent Claim
49 words
A keyboard, comprising a plurality of regular keys; and an inverted T-shaped key located in a middle of the keyboard, having a `Space` and an `Enter` function, and subdividing said regular keys into two sections including one section for preferably left-hand operation and another section preferably for right-hand operation.
Claim 3
Dependent Claim
29 words
A keyboard as defined in claim 1, wherein said T-shaped key has a bottom portion provided for a `Space` function and a top portion provided for an `Enter` function.
Claim 4
Dependent Claim
28 words
A keyboard as defined in claim 1, wherein said regular keys are arranged in rows of keys, said rows of keys being located on a tilted flat plane.
Claim 5
Dependent Claim
22 words
A keyboard as defined in claim 1, wherein said regular keys are arranged in key columns located on a flat tilted surface.
Claim 6
Dependent Claim
53 words
A keyboard, comprising a plurality of regular keys; and an inverted T-shaped key subdividing said regular keys into two sections including one section for preferably left-hand operation and another section for preferably right-hand operation, said regular keys being arranged in rows of keys, said rows of keys being located on concave cylindrical surfaces.
Claim 7
Dependent Claim
53 words
A keyboard, comprising a plurality of regular keys; and an inverted T-shaped key subdividing said regular keys into two sections including one section for preferably left-hand operation and another section for preferably right-hand operation, said regular keys being arranged in rows of keys, said rows of keys being located on concave cylindrical surfaces.
Claim 8
Dependent Claim
33 words
A keyboard as defined in claim 5, wherein said concave cylindrical surfaces have rotation axes extending parallel to said row of keys in the left and in the right section of the keyboard.
Claim 9
Dependent Claim
31 words
A keyboard as defined in claim 6, wherein said rotation axes intersect the vertical central line of said inverted T-shaped key at 75°-90° from the left and from the right, respectively.
Claim 10
Dependent Claim
54 words
A keyboard, comprising a plurality of regular keys; an inverted T-shaped key subdividing said regular keys into two sections including one section for preferably left-hand operation and another section preferably for right-hand operation; and a trackball located at a top part of the keyboard at a vertical central line of said inverted T-shaped key.
Claim 11
Dependent Claim
54 words
A keyboard, comprising a plurality of regular keys; an inverted T-shaped key subdividing said regular keys into two sections including one section for preferably left-hand operation and another section preferably for right-hand operation; and a trackball located at a top part of the keyboard at a vertical central line of said inverted T-shaped key.
Claim 12
Dependent Claim
64 words
A keyboard, comprising a plurality of regular keys; an inverted T-shaped key subdividing said regular keys into two sections including one section for preferably left-hand operation and another section for preferably right-hand operation; and two rollers located at a top or a bottom part of a keyboard to the left or to the right of a vertical central line of said inverted T-shaped key.
Claim 13
Dependent Claim
64 words
A keyboard, comprising a plurality of regular keys; an inverted T-shaped key subdividing said regular keys into two sections including one section for preferably left-hand operation and another section for preferably right-hand operation; and two rollers located at a top or a bottom part of a keyboard to the left or to the right of a vertical central line of said inverted T-shaped key.
Claim 14
Dependent Claim
55 words
A keyboard, comprising a plurality of regular keys; an inverted T-shaped key subdividing said regular keys into two sections including one section for preferably left-hand operation and another section for preferably right-hand operation, said regular keys being arranged in key columns located on concave cylindrical surfaces with a curvature radius of 6 cm or more.
Claim 15
Dependent Claim
55 words
A keyboard, comprising a plurality of regular keys; an inverted T-shaped key subdividing said regular keys into two sections including one section for preferably left-hand operation and another section for preferably right-hand operation, said regular keys being arranged in key columns located on concave cylindrical surfaces with a curvature radius of 6 cm or more.
Claim 16
Dependent Claim
44 words
A keyboard, comprising a plurality of regular keys; and an inverted T-shaped key subdividing said regular keys into two sections including one section for preferably left-hand operation and another section for preferably right-hand operation, each of said regular keys having a top cylindrical depression.
Claim 17
Dependent Claim
44 words
A keyboard, comprising a plurality of regular keys; and an inverted T-shaped key subdividing said regular keys into two sections including one section for preferably left-hand operation and another section for preferably right-hand operation, each of said regular keys having a top cylindrical depression.
Claim 18
Dependent Claim
35 words
A keyboard as defined in claim 11, wherein said top cylindrical depressions in each column of said keys together form a continuous groove with the central line substantially perpendicular to the rows of said keys.
Claim 19
Dependent Claim
61 words
A keyboard, comprising a plurality of regular keys; and an inverted T-shaped key subdividing said regular keys into two sections including one section for preferably left-hand operation and another section for preferably right-hand operation, each of said keys having a key cap provided with a central hole helping to center a finger and develop a finger motor reaction in touch-typing training.
Claim 20
Dependent Claim
61 words
A keyboard, comprising a plurality of regular keys; and an inverted T-shaped key subdividing said regular keys into two sections including one section for preferably left-hand operation and another section for preferably right-hand operation, each of said keys having a key cap provided with a central hole helping to center a finger and develop a finger motor reaction in touch-typing training.
Claim 21
Dependent Claim
32 words
A keyboard as defined in claim 13; and further comprising a key top mountable on each of said key caps and having a snap insert for its fixation in said central hole.
Claim 22
Dependent Claim
18 words
A keyboard as defined in claim 14, wherein said central hole and said insert have a truncated-cone shape.
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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) | 1995-10-20 | 1996-04-20 | 1996-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-10-20 | 2000-04-20 | 2000-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-10-20 | 2004-04-20 | 2004-10-20 | $7700.00 | Window Closed / Lapsed |