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US3812277A Expired / Lapsed US ⏱️ 0.0 years remaining

Demonstration typewriter keyboard wall chart

Assignee: Individual
•
Filing: 1973-01-30
•
Granted: 1974-05-21
•
Expires: 1993-01-30
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Abstract

Abstract A demonstration typewriter keyboard wall chart system having a display of visible indicia representing keys of a typewriter keyboard, and lamps associated with the keys for selectively illuminating same. The lamps are actuated by switches operatively connected to the lamps. These switches are push-button switches in which the actuating stem has been provided with a hole. The shank of a tack having a substantially planar head is inserted in the stem hole to simulate a keyboard key. A plurality of circuits each including a lamp and switch are connected to the output of a step-down transformer so that low-voltage elements may be employed.

Inventors

  • 👤 B Swartzman

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 03:41
CPC Classifications
G; G09; G09B; G09B13/00

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 189 words
A demonstration typewriter keyboard wall chart system, comprising, in combination: a. a display of indicia clearly visible without illumination and representing keys of a typewriter keyboard; b. means for individually illuminating each of said keys, the illuminating means being a plurality of lamps, each lamp associated with an individual key on the display, each lamp including a lens which gives off a star of light highlighting the associated indicia representing a key, the clearly visible indicia and selected keys highlighted by illumination providing an easily readable display; and c. means for selectively actuating the illuminating means, the actuating meaNs including a plurality of normally-open switches, a housing, each switch mounted on the housing in isolation from each other switch and operatively connected to a lamp and associated therewith as a set, each switch being formed by a push-button switch having an actuating stem, each such push-button switch being provided with a hole, and a tack having a shank inserted into the hole for retention thereby, the tack also having a substantially planar head arranged to simulate a typewriter key and arranged for actuating an associated lamp on being pushed.
Claim 2
Dependent Claim 189 words
A demonstration typewriter keyboard wall chart system, comprising, in combination: a. a display of indicia clearly visible without illumination and representing keys of a typewriter keyboard; b. means for individually illuminating each of said keys, the illuminating means being a plurality of lamps, each lamp associated with an individual key on the display, each lamp including a lens which gives off a star of light highlighting the associated indicia representing a key, the clearly visible indicia and selected keys highlighted by illumination providing an easily readable display; and c. means for selectively actuating the illuminating means, the actuating meaNs including a plurality of normally-open switches, a housing, each switch mounted on the housing in isolation from each other switch and operatively connected to a lamp and associated therewith as a set, each switch being formed by a push-button switch having an actuating stem, each such push-button switch being provided with a hole, and a tack having a shank inserted into the hole for retention thereby, the tack also having a substantially planar head arranged to simulate a typewriter key and arranged for actuating an associated lamp on being pushed.
Claim 3
Dependent Claim 36 words
A structure as defined in claim 1, wherein a substantially rectangular framework is provided with a pair of open faces, and a planar member is arranged covering one of the open faces for forming the display.
Claim 4
Dependent Claim 26 words
A structure as defined in claim 2, wherein the planar member is a flexible and transparent wall chart, and the indicia is arranged in five rows.
Claim 5
Dependent Claim 27 words
A structure as defined in claim 3, further including a panel covering the other of the open faces, and wherein the lamps are mounted on this panel.
Claim 6
Dependent Claim 41 words
A structure as defined in claim 4, further including a transformer mounted on the framework having an input selectively connectible to a source of electric power and an output connected in series with each set of a lamp and associated switch.
Claim 7
Dependent Claim 61 words
A structure as defined in claim 1, wherein the housing has a rectangular, planar base, and a plurality of walls affixed to and extending co-directionally from the base, and at least some of these walls provided with recesses forming steps to receive a portion of a switch and space same from the base, and cutouts for permitting the passage of wires.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1977-05-20 1977-11-19 1978-05-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-05-20 1981-11-19 1982-05-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-05-20 1985-11-19 1986-05-21 $7700.00 Window Closed / Lapsed

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