US3700318A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Film gate
Assignee: ANACOMP Inc 11550 NORTH MERIDAN STREET CARMEL INDIANA 46032 A CORP OF INDIANA
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Filing: 1971-04-26
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Granted: 1972-10-24
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Expires: 1991-04-26
Abstract
Abstract An improved film gate for motion picture projectors, microfilm viewers and the like is disclosed. The film gate consists essentially of rigid fixed platen and an arcuate spring platen. The platens have cooperating apertures corresponding to the film frame size. During film movement through the film gate the platens are spaced apart to serve as guides. While the film is stopped for viewing, the spring platen presses the film against the fixed platen. The arcuate configuration of the spring platen provides rolling contact as it closes to prevent film damage.
Inventors
- 👤 Omar Leo Cunningham Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:11
CPC Classifications
G; G03; G03B; G03B1/00; G03B1/56
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
160 words
A film gate comprising: a. an elongated channel of generally rectangular cross-section sized to permit a film strip to pass freely therethrough; b. a fixed platen forming one side of said channel; c. a movable platen forming at least part of the side of said channel opposite to said fixed platen; d. corresponding apertures in said platens to permit light to pass from a light source through film in said channel To a projection surface; e. said movable platen comprising an elongated bowed spring, with the convex surface toward said channel, said spring biased to move said platen away from said fixed platen; and f. clamping means comprising a solenoid to move the convex apertured center portion of said movable platen toward said fixed platen against said spring bias, whereby initial contact with film in said channel is along a line at about the center of said aperture and further clamping occurs in a rolling manner outwardly from that line.
Claim 2
Dependent Claim
160 words
A film gate comprising: a. an elongated channel of generally rectangular cross-section sized to permit a film strip to pass freely therethrough; b. a fixed platen forming one side of said channel; c. a movable platen forming at least part of the side of said channel opposite to said fixed platen; d. corresponding apertures in said platens to permit light to pass from a light source through film in said channel To a projection surface; e. said movable platen comprising an elongated bowed spring, with the convex surface toward said channel, said spring biased to move said platen away from said fixed platen; and f. clamping means comprising a solenoid to move the convex apertured center portion of said movable platen toward said fixed platen against said spring bias, whereby initial contact with film in said channel is along a line at about the center of said aperture and further clamping occurs in a rolling manner outwardly from that line.
Claim 3
Dependent Claim
69 words
The film gate according to claim 1 wherein said movable platen includes two end mounting portions, each adapted to be held at a fixed substantially equal distance from said fixed platen while permitting movement of said end portions toward and away from each other in a plane generally parallel to said channel during movement of the center portion of said movable platen toward and away from said fixed platen.
Claim 4
Dependent Claim
40 words
The film gate according to claim 1 further including at least one guide pin extending from said fixed platen through corresponding holes in said movable platen to guide said movable platen during movement toward and away from said fixed platen.
Claim 5
Dependent Claim
156 words
In a film gate comprising a channel through which a film strip can be freely moved, a fixed platen and a movable platen forming the walls of said channel parallel to the faces of a film strip positioned therebetween, each of said platens having a light passing aperture corresponding to film frames and closing means to move said movable platen toward said fixed platen to clamp a film strip positioned therebetween; the improvement wherein said movable platen comprises a spring member bowed with the convex side toward said fixed platen and biased away from said fixed platen and said closing means comprises a solenoid adapted to further bow said spring against said biasing force to bring the apertured portion of said movable platen into clamping relationship with said fixed platen, whereby initial contact is along a line at about the center of said aperture and further clamping contact in a rolling manner outwardly from that line.
Claim 6
Dependent Claim
156 words
In a film gate comprising a channel through which a film strip can be freely moved, a fixed platen and a movable platen forming the walls of said channel parallel to the faces of a film strip positioned therebetween, each of said platens having a light passing aperture corresponding to film frames and closing means to move said movable platen toward said fixed platen to clamp a film strip positioned therebetween; the improvement wherein said movable platen comprises a spring member bowed with the convex side toward said fixed platen and biased away from said fixed platen and said closing means comprises a solenoid adapted to further bow said spring against said biasing force to bring the apertured portion of said movable platen into clamping relationship with said fixed platen, whereby initial contact is along a line at about the center of said aperture and further clamping contact in a rolling manner outwardly from that line.
Claim 7
Dependent Claim
69 words
The film gate according to claim 4 wherein said movable platen includes two end mounting portions each adapted to be held at a substantially equal fixed distance from said fixed platen while permitting movement of said end portions toward and away from each other in a plane generally parallel to said channel during movement of the center portion of said movable platen toward and away from said fixed platen.
Claim 8
Dependent Claim
43 words
The film gate according to claim 4 wherein said movable platen has at least one guide opening adapted to cooperate with a guide pin on said fixed platen to guide said movable platen during movement thereof toward and away from said fixed platen.
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) | 1975-10-24 | 1976-04-24 | 1976-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-24 | 1980-04-24 | 1980-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-24 | 1984-04-24 | 1984-10-24 | $7700.00 | Window Closed / Lapsed |