US3924941A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cassette and cassette holder for improved controlled-reading device
Assignee: S&P Global Inc
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Filing: 1973-12-13
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Granted: 1975-12-09
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Expires: 1993-12-13
Abstract
Abstract A film cassette in the form of an elongated hollow box is provided with a continuous loop of film having sprocket perforations for advancement of the film. The loop extends around guides at opposite ends and one intermediate run of the film is twisted approximately 90* about its longitudinal axis and is passed between guides holding the film in a plane perpendicular to and on center with the lens axis. The film run passes an opening in the cassette walls at a predetermined position along its length to permit projection and through which a film positioning element may project. The film run also passes an opening in the casing through which a sprocket wheel drive may project to drive the film by its perforations. The cassette is provided with a predetermined cross-section corresponding in shape to a guide in the projector frame for receiving the cassette so that its cross-sectional form will determine a unique orientation for the cassette within the guide.
Inventors
- 👤 Elliott P Smith
- 👤 Robert H Wachsmuth
- 👤 Leonard Skolnick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:25
CPC Classifications
G; G03; G03B; G03B23/00; G03B23/08; G03B23/12; G03B21/00; G03B21/14; G03B21/32; G03B21/321; G03B21/323; G03B21/325
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
223 words
A film cassette for a continuous film loop without reel means comprising: an elongated hollow housing of standardized fixed dimensions having at least projecting and driving apertures for projecting the film through the housing and for admitting drive means to the housing, a continuous single taut loop of film within said housing having sprocket perforations for advancing the film longitudinally, guide means within said holder including end guide means adjacent opposite ends of the elongated housing about which said film loop extends defining an elongated narrow loop path without the film contacting itself, including at least one movable guide means within said holder along said path and further guide means intermediate said end guide means along said loop path positioned to gradually twist at least one run of said loop substantially 90* about its longitudinal axis so that the film is generally parallel to planes normal to the film in the rest of the loop as the film loop path passes the projecting and driving apertures, and back again into its initial plane beyond said apertures, resilient tensioning means urging said movable guide means into said loop path in such direction as to render said loop taut and apply tension through the entire length of the continuous loop of film which tension facilitates cooperation with the drive and projection elements of a projector.
Claim 2
Dependent Claim
223 words
A film cassette for a continuous film loop without reel means comprising: an elongated hollow housing of standardized fixed dimensions having at least projecting and driving apertures for projecting the film through the housing and for admitting drive means to the housing, a continuous single taut loop of film within said housing having sprocket perforations for advancing the film longitudinally, guide means within said holder including end guide means adjacent opposite ends of the elongated housing about which said film loop extends defining an elongated narrow loop path without the film contacting itself, including at least one movable guide means within said holder along said path and further guide means intermediate said end guide means along said loop path positioned to gradually twist at least one run of said loop substantially 90* about its longitudinal axis so that the film is generally parallel to planes normal to the film in the rest of the loop as the film loop path passes the projecting and driving apertures, and back again into its initial plane beyond said apertures, resilient tensioning means urging said movable guide means into said loop path in such direction as to render said loop taut and apply tension through the entire length of the continuous loop of film which tension facilitates cooperation with the drive and projection elements of a projector.
Claim 3
Dependent Claim
81 words
The film cassette of claim 1 in which the projecting aperture extends completely through the housing in a region of said at least one run of said loop twisted at 90* at a level aligned with the lens axis when the cassette is in projecting position in a projector and the aperture is of such size and arrangement to permit entry of alignment means into the cassette into contact with the film for holding the film in a fixed predetermined plane.
Claim 4
Dependent Claim
87 words
The film cassette of claim 2 in which guide means holding the film laterally as well as in its loop path are provided each side of the projection aperture such that entry into the cassette of alignment means will deflect the film against the tension of the resilient tensioning means from its loop path between the guide means on each side of the aperture normally defining the plane of the film in that portion of its loop path to thereby provide an alignment force within the cassette.
Claim 5
Dependent Claim
52 words
The film cassette of claim 1 in which the driving aperture is an opening in the housing opposite sprocket perforations in the film in a region of said at least one run of said loop twisted at 90* whereby drive means may enter the housing to drive the film by said perforations.
Claim 6
Dependent Claim
74 words
The film cassette of claim 4 in which guide means holding the film laterally as well as in its loop path are provided each side of the projection aperture such that entry into the cassette of drive means will defLect the film from its loop path between the guide means on each side of the driving aperture against the tension of the resilient tensioning means to thereby provide an alignment force within the cassette.
Claim 7
Dependent Claim
28 words
The film cassette of claim 5 in which the aperture is of such size and configuration as to permit entry of a sprocket wheel to drive said film.
Claim 8
Dependent Claim
52 words
The cassette of claim 1 in which the elongated housing has a form extending from one end for a predetermined distance providing a cross-section transversse to its length which is asymmetrical and of such form as to permit lengthwise insertion in only one orientation into a projector guide of predetermined conforming form.
Claim 9
Dependent Claim
46 words
The cassette of claim 7 in which the asymmetrical cross-section permitting insertion into said projector guide is provided only at one end and the other end has a form which does not permit insertion into the guide whereby the cassette may not be inserted upside down.
Claim 10
Dependent Claim
26 words
The film cassette of claim 3 in which lateral guide means are also provided each side of the aperture to preserve lateral alignment of the film.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-08 | 1979-06-09 | 1979-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-08 | 1983-06-09 | 1983-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-08 | 1987-06-09 | 1987-12-09 | $7700.00 | Window Closed / Lapsed |