Patent US2310642A successfully refreshed from Google Patents.
Patent US3911487A successfully refreshed from Google Patents.
US3911487A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic tape playback unit which sequentially switches between four tracks by detecting end of track silence
Assignee: Individual
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Filing: 1973-02-23
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Granted: 1975-10-07
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Expires: 1993-02-23
Abstract
Abstract Apparatus for reproducing sound recordings from a multi-track tape in a cassette or cartridge including a number of detecting heads each mounted for detecting signals from one of the tracks and a electronic switch for coupling each of the heads in turn to a sound producing circuit. Track changing can be initiated by detection of a period of silence exceeding a fixed time interval. The apparatus is preferably started on the same track by the insertion of a cassette or cartridge into the apparatus.
Inventors
- 👤 Serge Ladriere
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:22
CPC Classifications
G; G11; G11B; G11B27/00; G11B27/10; G11B27/19; G11B27/22; G11B15/00; G11B15/02; G11B15/16; G11B5/00; G11B5/48; G11B5/49; G11B5/4969
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
239 words
Apparatus for reproducing recordings from a tape having at least four tracks and mounted for movement in a case comprising: a plurality of magnetic heads each mounted for detecting signals from one of said tracks, means for moving said tape past said heads, means for receiving a signal from one of said heads and producing an audio output, electronic switch means for coupling any one of said heads to said receiving and producing means and means for controlling said switch means to cause each of said heads to be sequentially coupled one At a time to said receiving and producing means to play each of said four tracks and reverse the direction of tape movement after each track has been played including means connected to said receiving and producing means for producing a trigger signal when silence continues for greater than a predetermined length of time, means connected to said trigger signal producing means for reversing the direction of tape movement whenever said trigger signal is produced, means connected to said trigger signal producing means and responsive to said trigger signal for preventing a further trigger signal for a predetermined time after a trigger signal is produced, at least two multivibrators providing four output states each associated with one of said tracks and responsive to said trigger signal to change its output state, the output state determining which of said heads is coupled to said receiving and producing means.
Claim 2
Dependent Claim
239 words
Apparatus for reproducing recordings from a tape having at least four tracks and mounted for movement in a case comprising: a plurality of magnetic heads each mounted for detecting signals from one of said tracks, means for moving said tape past said heads, means for receiving a signal from one of said heads and producing an audio output, electronic switch means for coupling any one of said heads to said receiving and producing means and means for controlling said switch means to cause each of said heads to be sequentially coupled one At a time to said receiving and producing means to play each of said four tracks and reverse the direction of tape movement after each track has been played including means connected to said receiving and producing means for producing a trigger signal when silence continues for greater than a predetermined length of time, means connected to said trigger signal producing means for reversing the direction of tape movement whenever said trigger signal is produced, means connected to said trigger signal producing means and responsive to said trigger signal for preventing a further trigger signal for a predetermined time after a trigger signal is produced, at least two multivibrators providing four output states each associated with one of said tracks and responsive to said trigger signal to change its output state, the output state determining which of said heads is coupled to said receiving and producing means.
Claim 3
Dependent Claim
25 words
Apparatus as in claim 1 wherein said electronic switch means includes a plurality of field effect transistors equal in number to the number of tracks.
Claim 4
Dependent Claim
52 words
Apparatus as in claim 1 further including further switch means operable by the insertion of said case into the apparatus and means connected to further said switch means and said controlling means for causing said electronic switch means to couple a predetermined one of said heads to said receiving and producing means.
Claim 5
Dependent Claim
23 words
Apparatus as in claim 3 wherein said switch means couples said head to said receiving and producing means in a predetermined, fixed order.
Claim 6
Dependent Claim
98 words
Apparatus as in claim 1 wherein said moving means includes a plate with a single motor driving continuously two capstans turning in opposite directions, two pressure pulleys each of which is carried by a rocker member and tightening alternately the magnetic tape against one of the pulleys of the capstan for the purpose of driving it into one direction or the other, a cam member for alternately shifting the two rockers, said cam being moved alternately by two relays of reverse action, each one of these relays being connected to the corresponding channels of said electronic switch means.
Claim 7
Dependent Claim
37 words
Apparatus as in claim 5 wherein each one of the relays is controlled by a device composed of two semiconductors forming a logical OR circuit and a Darlington amplifying stage with large gain feeding the associated relay.
Claim 8
Dependent Claim
194 words
Apparatus as in claim 1 wherein said moving means includes a plate with three motors comprising on the one hand, on a mobile chassis, a main motor producing the driving of said magnetic tape by means of two capstans of reverse rotation, two auxiliary motors with weak coupling placed alternately in service and controlling the rotation of the winding reel, and, on the other hand a fixed chassis carrying the cassette comprising two relays each one of which moves a pressure pulley of the magnetic tape against the spindle of the adjacent capstan, means for locking and unlocking said mobile chassis with respect to the fixed chassis of the plate, means for keeping the mobile chassis in the low position, means acting against these maintenance means when the cassette is inserted into the fixed chassis and means for bringing this mobile chassis to the high position during the unlocking, relays and motors being controlled from a general supply unit supplying the necessary currents, and two further circuits for controlling in synchronization a pair of relays, one of the relays for activating the pressure pulley and the relay of the auxiliary motor correspnding to it.
Claim 9
Dependent Claim
48 words
Apparatus as in claim 7 wherein each module of control of said pair of relays comprises a circuit in logical OR receiving said signals from two decoding channels, the signals coming out of the logical OR circuit being amplified to make it possible to activate the relays concerned.
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) | 1978-10-06 | 1979-04-07 | 1979-10-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-06 | 1983-04-07 | 1983-10-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-06 | 1987-04-07 | 1987-10-07 | $7700.00 | Window Closed / Lapsed |