US4076112A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Free platen typewriter
Assignee: Individual
•
Filing: 1976-04-30
•
Granted: 1978-02-28
•
Expires: 1996-04-30
Abstract
Abstract The free platen has a weight inside to produce inertia against movement by typing, as well as extensible end pieces for extension to correspond to lateral extension of a paper guide. An adjustable end plate at each end of the typewriter frame carries a lower supporting and positioning roller which engages the platen at a point forwardly of the vertical centerline thereof and a rear supporting and positioning roller which is essentially opposite the point of impact of the typing element and engages the platen at a point below its horizontal centerline. The platen has a pair of ring gears having an outer diameter less than the thickness of the elastomer covering the platen between the gears, with a short section of elastomer beyond each ring gear. The ring gears are engaged by a gear of a pivoted indexing device, which gear engages the platen ring gear when the respective indexing device is in down position. The ratcheted indexing device is actuated by conventional levers, arms, etc. The rollers of a special bail engage the paper just above the printing line, the rollers being mounted on a rod supported by a forwardly extending bar at each end. A spring acting on each end bar provides a thrust force directed at an acute angle to a tangent to the platen at the point of engagement by the rollers. Conventional paper feed rollers are disposed underneath the platen but are pressed upwardly against the platen with sufficient force to hold the paper against the platen, but insufficient to lift the platen from its supporting rollers.
Inventors
- 👤 Cecil S. Effinger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:52
CPC Classifications
B; B41; B41J; B41J13/00; B41J13/02; B41J13/03; B41J11/00; B41J11/02; B41J11/04
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
289 words
In a typewriter having a frame and keyboard means for controlling means for imprinting characters on a sheet: a free platen around which said sheet may be moved by turning said platen, for imprinting characters thereon, said platen having free ends and being movable to different endwise positions; an end plate at each side of said typewriter and each constructed and arranged to permit paper or the like to be moved around said platen and to extend from said plates laterally beyond either or both of said end plates; means for producing relative longitudinal movement between said character imprinting means and said platen; first supporting rollers rigidly mounted on said end plates and engaging the underside of the platen at each side, for supporting and positioning said platen, said first rollers engaging said platen below the horizontal centerline of said platen and forwardly of the vertical centerline of said platen but closer to the vertical centerline of said platen than to the horizontal centerline thereof; second supporting rollers rigidly mounted on said end plates and engaging the rear side of said platen at each side, for supporting and positioning said platen in conjunction with said first rollers, said second rollers engaging said platen below the horizontal centerline of said platen, rearwardly of the vertical centerline of said platen and essentially opposite the point of impact of said character means, said endwise movability of said platen being with respect to said rollers and said end plates; and paper feed rollers between said end plates at both longitudinally and circumferentially spaced positions relative to the underside of said platen and adjustable toward and away from said platen separately from both said first and second rollers and resiliently urged against said platen.
Claim 2
Dependent Claim
289 words
In a typewriter having a frame and keyboard means for controlling means for imprinting characters on a sheet: a free platen around which said sheet may be moved by turning said platen, for imprinting characters thereon, said platen having free ends and being movable to different endwise positions; an end plate at each side of said typewriter and each constructed and arranged to permit paper or the like to be moved around said platen and to extend from said plates laterally beyond either or both of said end plates; means for producing relative longitudinal movement between said character imprinting means and said platen; first supporting rollers rigidly mounted on said end plates and engaging the underside of the platen at each side, for supporting and positioning said platen, said first rollers engaging said platen below the horizontal centerline of said platen and forwardly of the vertical centerline of said platen but closer to the vertical centerline of said platen than to the horizontal centerline thereof; second supporting rollers rigidly mounted on said end plates and engaging the rear side of said platen at each side, for supporting and positioning said platen in conjunction with said first rollers, said second rollers engaging said platen below the horizontal centerline of said platen, rearwardly of the vertical centerline of said platen and essentially opposite the point of impact of said character means, said endwise movability of said platen being with respect to said rollers and said end plates; and paper feed rollers between said end plates at both longitudinally and circumferentially spaced positions relative to the underside of said platen and adjustable toward and away from said platen separately from both said first and second rollers and resiliently urged against said platen.
Claim 3
Dependent Claim
30 words
In a typewriter as defined in claim 1, including: means for adjusting said first and second rollers, forwardly and rearwardly and upwardly and downwardly, independently of said paper feed rollers.
Claim 4
Dependent Claim
80 words
In a typewriter as defined in claim 1, wherein: said platen includes a tube and an elongated weight disposed within said tube and extending longitudinally thereof, said weight providing inertia against movement of said platen from the impacts of imprinting characters and having sufficient weight to resist an upward thrust of said paper feed rollers sufficient to maintain said paper in engagement with said platen during the imprinting of characters without lifting the platen from said first and second rollers.
Claim 5
Dependent Claim
29 words
In a typewriter as defined in claim 1, including: means for urging said sheet against said platen at positions adjacent and above the impact area of said imprinting means.
Claim 6
Dependent Claim
63 words
In a typewriter as defined in claim 4 wherein said sheet urging means includes: a rod parallel to said platen and provided with rollers for engaging said sheet; and means for resiliently urging said rod toward said platen by an essentially horizontal force directed toward the circumference of said platen at the point of engagement of said sheet covered platen by said rollers.
Claim 7
Dependent Claim
39 words
In a typewriter as defined in claim 5, wherein: said resilient urging means include movable elements attached to the respective ends of said rod; and a spring acting on each movable element to urge said rod toward said platen.
Claim 8
Dependent Claim
86 words
In a typewriter as defined in claim 6, wherein: said movable elements include an upright plate at each side and attached to each end of said rod, each said plate having a slot provided with a downward front offset; a pair of aligned guide pins for and engageable with each said slot; and spring means for urging said elements toward said platen, one of said pins engageable with the offset in said slot for retaining said plates and rod in a position away from said platen.
Claim 9
Dependent Claim
57 words
In a typewriter as defined in claim 1, including: indexing means including gear means for turning said platen in predetermined increments; and friction roller means for alternatively turning said platen through engagement with said platen at a position spaced from said sheet or engagement with said sheet at a position at which said sheet covers said platen.
Claim 10
Dependent Claim
65 words
In a typewriter as defined in claim 8, wherein: said platen is provided with a covering of an elastomer adapted to receive the impact of typing characters striking the paper extending around the platen; and said gear means includes a ring gear mounted on said platen but flanked on each side by said elastomer and extending radially for a distance no greater than said elastomer.
Claim 11
Dependent Claim
53 words
In a typewriter as defined in claim 9, wherein: said elastomer covering in the direction of the free end of said platen extends for a predetermined distance from said ring gear; and said friction roller means is disposed outwardly from a gear of said indexing means a greater distance than said predetermined distance.
Claim 12
Dependent Claim
65 words
In a typewriter as defined in claim 8, wherein: said friction roller means comprises a roller mounted on said indexing means and said gear means includes a gear mounted on said indexing means; the maximum diameter of said roller is greater than the maximum diameter of said gear; and said indexing means includes a ratchet means for turning said gear and said roller in increments.
Claim 13
Dependent Claim
180 words
A free platen typewriter having means for supporting said platen at points a predetermined distance apart and means for imprinting characters at selected positions on a sheet extending around said platen, said platen having free ends, being movable to different endwise positions, receiving a sheet extending around the same having a width greater than the length of said platen and including: a tube having a length greater than said predetermined distance; a covering of an elastomer extending on said tube for a length greater than said predetermined distance; tubular end extensions slidable within said tube from the opposite ends thereof and adapted to receive a sheet extending around both of said extensions, when fully extended, and wider than the combined length of said platen and the fully extended extensions; a weight disposed within said tube and extending longitudinally thereof, said weight being cylindrical and having an outer diameter less than the inner diameter of said platen tube; and said tubular end extensions surrounding and being slidable along said weight between said weight and the elastomer covered portion of said tube.
Claim 14
Dependent Claim
180 words
A free platen typewriter having means for supporting said platen at points a predetermined distance apart and means for imprinting characters at selected positions on a sheet extending around said platen, said platen having free ends, being movable to different endwise positions, receiving a sheet extending around the same having a width greater than the length of said platen and including: a tube having a length greater than said predetermined distance; a covering of an elastomer extending on said tube for a length greater than said predetermined distance; tubular end extensions slidable within said tube from the opposite ends thereof and adapted to receive a sheet extending around both of said extensions, when fully extended, and wider than the combined length of said platen and the fully extended extensions; a weight disposed within said tube and extending longitudinally thereof, said weight being cylindrical and having an outer diameter less than the inner diameter of said platen tube; and said tubular end extensions surrounding and being slidable along said weight between said weight and the elastomer covered portion of said tube.
Claim 15
Dependent Claim
25 words
A free platen typewriter as defined in claim 12, wherein: the diameter of said weight is a multiple of the thickness of said platen tube.
Claim 16
Dependent Claim
199 words
A free platen typewriter having means for supporting said platen at points a predetermined distance apart and means for imprinting characters at selected positions on a sheet extending around said platen, said platen having free ends, being movable to different endwise positions, receiving a sheet extending around the same having a width greater than the length of said platen and including: a tube having a length greater than said predetermined distance; a covering of an elastomer extending for a length greater than said predetermined distance; tubular end extensions slidable within said tube from the opposite ends thereof; a weight disposed within said tube and extending longitudinally thereof, said weight being cylindrical and having an outer diameter less than the inner diameter of said platen tube; a central bushing of limited extent engaging the inside of said tube and the outside of said weight for supporting said weight centrally of said tube; said tubular end extensions surrounding and being slidable along said weight and being provided at the inner ends with ring-shaped bushings which are slidable with said tubular end extensions; and said tube being provided adjacent each end with an inside, ring-shaped bushing surrounding the corresponding tubular end extension.
Claim 17
Dependent Claim
199 words
A free platen typewriter having means for supporting said platen at points a predetermined distance apart and means for imprinting characters at selected positions on a sheet extending around said platen, said platen having free ends, being movable to different endwise positions, receiving a sheet extending around the same having a width greater than the length of said platen and including: a tube having a length greater than said predetermined distance; a covering of an elastomer extending for a length greater than said predetermined distance; tubular end extensions slidable within said tube from the opposite ends thereof; a weight disposed within said tube and extending longitudinally thereof, said weight being cylindrical and having an outer diameter less than the inner diameter of said platen tube; a central bushing of limited extent engaging the inside of said tube and the outside of said weight for supporting said weight centrally of said tube; said tubular end extensions surrounding and being slidable along said weight and being provided at the inner ends with ring-shaped bushings which are slidable with said tubular end extensions; and said tube being provided adjacent each end with an inside, ring-shaped bushing surrounding the corresponding tubular end extension.
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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) | 1981-02-27 | 1981-08-29 | 1982-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-27 | 1985-08-29 | 1986-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-27 | 1989-08-29 | 1990-02-28 | $7700.00 | Window Closed / Lapsed |