Patent US3661449A successfully refreshed from Google Patents.
US3661449A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Overhead visual shutter device
Assignee: NEWBURG ACQUISITION Inc
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Filing: 1969-05-19
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Granted: 1972-05-09
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Expires: 1989-05-19
Abstract
Abstract An overhead projector shutter assembly having a frame defining a window and a number of slides movably mounted in the frame to mask the window, the slides being selectively and relatively movable to mask and unmask selected portions of the window or the entire window to project selected portions of the total transparency onto a screen in sequence. The slides are overlapped with each other and with the frame along adjacent edges to completely exclude unwanted light and to promote smoothness of operation on guides which assure accuracy of alignment between the slides and the register pins which locate the transparency.
Inventors
- 👤 John S Wright
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 04:56
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/132
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
79 words
A stage for supporting transparencies in an overhead projector system, said stage comprising a frame with inner and outer margins and a fullsize projection opening, a transparent sheet mounted on said frame for the support of transparencies to be projected, register pins on the frame for the precise location on said sheet Of successive transparencies for projection, and a shutter having means mounting it on said frame for movement beneath the transparent sheet on which the transparencies are supported.
Claim 2
Dependent Claim
79 words
A stage for supporting transparencies in an overhead projector system, said stage comprising a frame with inner and outer margins and a fullsize projection opening, a transparent sheet mounted on said frame for the support of transparencies to be projected, register pins on the frame for the precise location on said sheet Of successive transparencies for projection, and a shutter having means mounting it on said frame for movement beneath the transparent sheet on which the transparencies are supported.
Claim 3
Dependent Claim
56 words
A stage in accordance with claim 1 in which a plurality of shutters are disposed beneath the transparent sheet for relative movement between positions to open and to mask specifically identified portions of the sheet and the transparency thereon, margins of the respective shutters having edge portions lapping each other and respective portions of the frame.
Claim 4
Dependent Claim
46 words
A stage in accordance with claim 2 in which the frame comprises side members with slots through which respective shutters are movable outwardly from completely effective mask positions to positions in which areas of said transparent sheet controlled by the respective shutters are substantially fully exposed.
Claim 5
Dependent Claim
27 words
A stage according to claim 3 in which the shutters and frame have mutually engageable limiting means for restraining outward shutter movement beyond the last mentioned positions.
Claim 6
Dependent Claim
117 words
For use with an overhead projector, a shutter assembly having a frame provided with inner and outer margins and a full size projection opening, a set of masks movable between first positions for completely closing said opening and second positions for completely exposing said opening and selected positions for closing only selected portions of said opening, and first guide means on the inside margin of the frame and additional guide means on the masks for guiding said masks for movement between said positions, whereby said masks may pass to their respective second positions, and means for limiting the movement of said masks to preclude movement from their said first positions to points materially beyond said second position.
Claim 7
Dependent Claim
117 words
For use with an overhead projector, a shutter assembly having a frame provided with inner and outer margins and a full size projection opening, a set of masks movable between first positions for completely closing said opening and second positions for completely exposing said opening and selected positions for closing only selected portions of said opening, and first guide means on the inside margin of the frame and additional guide means on the masks for guiding said masks for movement between said positions, whereby said masks may pass to their respective second positions, and means for limiting the movement of said masks to preclude movement from their said first positions to points materially beyond said second position.
Claim 8
Dependent Claim
22 words
A shutter assembly according to claim 5 in which said masks have handle flanges exposed at the outer margins of said frame.
Claim 9
Dependent Claim
25 words
A shutter assembly according to claim 6 in which the means for limiting mask movement comprises flanges engageable with the inner margins of the frame.
Claim 10
Dependent Claim
26 words
A shutter assembly according to claim 5 in which the frame comprises upper and lower elements spaced to provide slots through which said masks are movable.
Claim 11
Dependent Claim
31 words
A shutter assembly according to claim 8 in which the upper elements have exterior recesses and the masks have handle flanges seated therein in the said first positions of the masks.
Claim 12
Dependent Claim
25 words
A shutter assembly according to claim 5 in which the additional guide means comprises lapping marginal portions of the respective masks which are in engagement.
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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) | 1975-05-09 | 1975-11-08 | 1976-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-09 | 1979-11-08 | 1980-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-09 | 1983-11-08 | 1984-05-09 | $7700.00 | Window Closed / Lapsed |