Playback devices

• US 3,918,801 A
• Filed: 10/02/1973
• Issued: 11/11/1975
• Est. Priority Date: 10/03/1972
• Status: Expired due to Term

• Current Assignee: Friedrich Bauhofer
• Original Assignee: Friedrich Bauhofer
• Inventors: Bauhofer, Friedrich
• Primary Examiner(s): Hayes, Monroe H.
• Application Number:
  US05/402,825
• Time in Patent Office: 770 Days
• Field of Search: 352/6,7,8,31,32,33,78C,133,22,72
• US Class Current: 352/72
• CPC Class Codes: G03B 31/04 in which sound track is not on, but is synchronised with, a moving-picture film

Abstract

A film projector, adapted to receive separate sound and film cassettes which are to be played together, is provided with a system for reading code marks on the cassettes before projection commences; this system has an output, which may be visual or automatically effective to exert an overriding control on the projector, if the code markers of the cassettes do not correspond. In this way the risk of playing the wrong sound track for a particular film is avoided. Also described are means for enabling differently shaped cassettes to be used, if desired, for the sound and film tracks.

Claims

1. In a motion-picture projector having reading means for concurrently reproducing the contents of a picture strip and a sound strip respectively stored in a pair of associated cassettes, in combination:

a manually loadable cassette holder receivable in the body of the projector for accommodating a picture cassette and a sound cassette in operative juxtaposition with said reading means upon insertion of said holder into said body, said cassettes being provided with distinctive markings in predetermined code positions;

first and second sensing means positioned to detect said markings of said picture and sound cassettes, respectively;

comparison means responsive to said first and second sensing means upon insertion of said holder into said body for ascertaining the presence of a predetermined correlation between the code markings of said picture and sound cassettes; and

signaling means connected to said comparison means for indicating the absence of said correlation.

2. The combination defined in claim 1 wherein said holder is provided with cover means closable to retain said cassettes therein, said first and second sensing means being mounted at least in part on said cover means for engagement with corresponding markings upon closure of said cover means.

3. The combination defined in claim 2 wherein said sensing means include a first set of contacts on said holder and a second set of contacts on said cover means positioned to complete an operating circuit for said signaling means upon engagement with respective markings distributed in correlated patterns on said cassettes.

4. The combination defined in claim 2 wherein said first and second sensing means comprise a pair of contact elements on said cover means positioned for concurrent scanning of successive pairs of corresponding code positions of said cassettes upon relative displacement of said holder and said cover means toward a closure position.

5. In a motion-picture projector having reading means for concurrently reproducing the contents of a piCture strip and a sound strip respectively stored in a pair of associated cassettes, in combination:

a manually loadable cassette holder receivable in the body of the projector for accommodating a picture cassette and a sound cassette in operative juxtaposition with said reading means upon insertion of said holder into said body, said cassettes being each provided with a plurality of predetermined code positions occupied at least in part by distinctive markings;

first and second sensing means provided with a support movable relatively to said holder for sequentially scanning the code positions of said picture and sound cassettes, respectively, to detect said markings during relative motion of said holder and said support;

comparison means responsive to said first and second sensing means upon insertion of said holder into said body for ascertaining the presence of a predetermined correlation between the code markings of said picture and sound cassettes; and

signaling means connected to said comparison means for indicating the absence of said correlation.

6. The combination defined in claim 5 wherein said body has an inlet for said holder, said support being placed adjacent said inlet with said first and second sensing means disposed thereon for sequentially scanning said code positions during insertion of said holder into said inlet.

7. The combination defined in claim 5 wherein said signaling means comprises inhibiting means for preventing operation of the projector in the absence of said correlation.

8. The combination defined in claim 7 wherein said inhibiting means comprises a mechanical detent.

9. The combination defined in claim 5 wherein said first and second sensing means comprise photoelectric scanning means forming separate light paths for detecting markings of distinctively different light-transmission characteristics on the respective cassettes.

10. The combination defined in claim 9 wherein said comparison means comprises a threshold switch discriminating between three voltage levels for determining the number of markings concurrently detected by said scanning means.

11. The combination defined in claim 10 wherein said threshold switch is a tunnel diode.

12. In message-reproducing apparatus having means for jointly reading the contents of two data carriers respectively stored in a pair of associated cassettes, in combination:

a manually loadable cassette holder receivable in the body of the apparatus for accommodating a first and a second cassette in operative juxtaposition with the respective reading means, said cassettes being provided with a plurality of predetermined code positions occupied at least in part by distinctive markings;

first and second sensing means provided with a support movable relatively to said holder for sequentially scanning the code positions of said first and second cassettes, respectively, to detect said markings during relative motion of said holder and said support;

comparison means responsive to said first and second sensing means upon insertion of said holder into said body for ascertaining the presence of a predetermined correlation between the code markings of said first and second cassettes; and

signaling means connected to said comparison means for indicating the absence of said correlation.

13. The combination defined in claim 12 wherein said body has an inlet for said holderr, said support being placed adjacent said inlet with said first and second sensing means disposed thereon for sequentially scanning said code positions during insertion of said holder into said inlet.

14. In a motion-picture projector having reading means for concurrently reproducing the contents of a picture strip and a sound strip respectively stored in a pair of associated cassettes, certain cassettes being provided with distinctive markings in predetermined code positions to indicate their pairing, other cassettes lacking said markings and having a configuraTion different from that of cassettes provided with said markings, in combination:

receiving means on the body of said projector provided with an inlet for a picture cassette and a sound cassette to be operatively juxtaposed with said reading means;

first and second sensing means at said inlet positioned to coact with markings on said picture and sound cassettes, respectively;

comparison means responsive to said first and second sensing means upon insertion of a picture cassette and a sound cassette into said inlet for ascertaining the presence of a predetermined correlation between the code markings thereof;

signaling means connected to said comparison means for indicating the absence of said correlation; and

shape-detecting means at said inlet responsive to said different configuration for deactivating said signaling means upon insertion of a cassette lacking said markings.

15. In message-reproducing apparatus having means for reading the contents of a data carrier stored in a cassette, in combination:

receiving means on the body of said apparatus provided with an inlet for the insertion of a cassette in operative position, said cassette being provided with a plurality of predetermined code positions occupied at least in part by distinctive markings;

sensing means provided on said body adjacent said inlet for sequentially scanning said code positions to detect said markings during insertion of the cassette and to convert the detected markings into a first series of code signals;

reference means for providing a second series of code signals;

comparison means connected to said sensing means and to said reference means for ascertaining the presence of a predetermined correlation between said first and second series of code signals; and

output means connected to said comparison means for indicating said correlation.