US3728494A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signal control system for endless tape recorder
Assignee: MC GRAW HILL CO
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Filing: 1971-11-15
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Granted: 1973-04-17
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Expires: 1991-11-15
Abstract
Abstract A dictating machine using an endless magnetic tape records a control signal alongside the audio track only during the recording of dictation, and forms an erased section in advance of the last recording when a playback control is depressed to listen back to a portion of the recording and when the operator hangs up the microphone denoting the end of his use of the machine. A control signal detector allows the operator to rewind only to the beginning of his dictation assuring privacy to each user, and shifts the machine automatically into recording when he advances the tape to the prior position of farthest advance. Fast rewind and/or fast forward drive of the tape are possible only when the machine is in playback or when the operator hangs up the microphone. Either loss of control signal or release of a manual playback control stops the rewind and starts a normal advance of the machine in playback condition, which then continues until the forward mark - i.e., erased section - is reached. However, if the user presses the manual record control during playback the tape is moved fast forward until the forward mark is reached and the machine is then shifted automatically into normal record condition. Various safety controls and timing circuits assure a well-nigh automatic and error-free use of the machine.
Inventors
- 👤 R Kobler
- 👤 W Fagan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:29
CPC Classifications
G; G11; G11B; G11B15/00; G11B15/02
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
246 words
In a machine for recording dictation and for selectively listening back thereto: the combination of a magnetic tape having parallel audio and control signal tracks therealong, an audio head for recording dictation on and for erasing the same from said audio track, a control signal head for recording a control signal on and for erasing the same from said control signal track, tape drive means, a speaker-microphone, a control signal source, a control signal relay operable to maintain a machine in selected operated conditions as long as said relay is held operated by signals picked up from the tape by said control signal head, a record-reproduce circuitry operable into record position to connect said microphone to said audio head and concurrently said signal source to said control signal head, and into reproduce position to connect said audio head to said speaker and said control signal head to said control signal relay, a manual record control operable to condition said drive means to advance the tape at normal speed and concurrently to shift said record-reproduce circuitry into record position, and a manual playback control operable to advance said tape for a predetermined interval and concurrently to feed erase signals to both said heads to provide an erased section on both tracks forming a forward mark, thereupon to backfeed the tape at above normal speed without applying signals to either head, and then to advance the tape at normal speed while placing said recordreproduce circuitry in reproduce condition.
Claim 2
Dependent Claim
246 words
In a machine for recording dictation and for selectively listening back thereto: the combination of a magnetic tape having parallel audio and control signal tracks therealong, an audio head for recording dictation on and for erasing the same from said audio track, a control signal head for recording a control signal on and for erasing the same from said control signal track, tape drive means, a speaker-microphone, a control signal source, a control signal relay operable to maintain a machine in selected operated conditions as long as said relay is held operated by signals picked up from the tape by said control signal head, a record-reproduce circuitry operable into record position to connect said microphone to said audio head and concurrently said signal source to said control signal head, and into reproduce position to connect said audio head to said speaker and said control signal head to said control signal relay, a manual record control operable to condition said drive means to advance the tape at normal speed and concurrently to shift said record-reproduce circuitry into record position, and a manual playback control operable to advance said tape for a predetermined interval and concurrently to feed erase signals to both said heads to provide an erased section on both tracks forming a forward mark, thereupon to backfeed the tape at above normal speed without applying signals to either head, and then to advance the tape at normal speed while placing said recordreproduce circuitry in reproduce condition.
Claim 3
Dependent Claim
207 words
In a machine for recording dictation and for selectively listening back thereto: the combination of a magnetic tape, audio and control heads for engaging said tape along respective parallel audio and control tracks, a tape drive means, shiftable record-reproduce means for conditioning said machine selectively for recording and for playback, a manual record control operable to start said drive means and to shift said record-reproduce means into record condition for recording dictation on said audio track, means responsive to operation of said manual record control for recording a control signal on said control track concurrently as the tape is moved to record dictation on said audio track, a manual playback control, and means responsive to operating said playback control for first advancing the tape a predetermined distance while applying eraSe signals to both of said heads, then backfeeding the tape a selected distance without applying any signals to said heads, and next shifting the machine into reproduce condition and advancing the tape at normal drive speed whereby an erased track section is provided on both the audio and control tracks of said tape beyond the point of farthest advance in recording forming a forward mark and then a selected portion of the recorded dictation is played back.
Claim 4
Dependent Claim
207 words
In a machine for recording dictation and for selectively listening back thereto: the combination of a magnetic tape, audio and control heads for engaging said tape along respective parallel audio and control tracks, a tape drive means, shiftable record-reproduce means for conditioning said machine selectively for recording and for playback, a manual record control operable to start said drive means and to shift said record-reproduce means into record condition for recording dictation on said audio track, means responsive to operation of said manual record control for recording a control signal on said control track concurrently as the tape is moved to record dictation on said audio track, a manual playback control, and means responsive to operating said playback control for first advancing the tape a predetermined distance while applying eraSe signals to both of said heads, then backfeeding the tape a selected distance without applying any signals to said heads, and next shifting the machine into reproduce condition and advancing the tape at normal drive speed whereby an erased track section is provided on both the audio and control tracks of said tape beyond the point of farthest advance in recording forming a forward mark and then a selected portion of the recorded dictation is played back.
Claim 5
Dependent Claim
39 words
The dictating machine set forth in claim 2 including means for detecting said control signal for maintaining the machine in operating condition after operation of said playback control until an absence of signal is detected on said control track.
Claim 6
Dependent Claim
58 words
The dictating machine set forth in claim 3 including delay means associated with said detecting means for continuing an advance of the tape a predetermined interval after an absence of control signal is detected whereby a portion of said erased section designating said forward mark is moved past the heads of the machine before the tape is stopped.
Claim 7
Dependent Claim
44 words
The dictating machine set forth in claim 4 including a second control head spaced from said first mentioned control head for applying a control signal over said portion of said erased section upon the tape being next advanced with the machine in recording condition.
Claim 8
Dependent Claim
61 words
The dictating machine set forth in claim 2 including means for conditioning said tape drive means to advance and backfeed the tape selectively at above-normal speed, a playback relay energized by operation of said manual playback control, and means controlled by said playback relay to render said drive means operable in fast forward and fast backfeed when said relay is operated.
Claim 9
Dependent Claim
106 words
The dictating machine set forth in claim 6 including a control signal detecting means, an on-off switch for said machine cooperable with said signal detecting means to cause the tape to be driven in fast-forward to a point where an absence of signal is detected in said control track when said on-off switch is returned to off position, and timing means activated by said signal detecting means when said absence of control signal is detected for reactivating said drive means in fast-forward for a predetermined interval and for concurrently feeding erase current to both said audio and control heads during the reactivation of said driving means.
Claim 10
Dependent Claim
110 words
The dictating machine set forth in claim 3 wherein said detecting means includes a control signal relay operated by signal picked up from said control track, a playback relay having a hold circuit controlled by said control signal relay for holding the playback relay energized so long as said control signal relay is held operated, means for maintaining said machine in operating playback condition so long as said playback relay is operated, and means for delaying drop out of said playback relay for an interval after drop out of said control signal relay whereby to produce an erased section on each track following the point where the recording last ended.
Claim 11
Dependent Claim
51 words
The dictating machine set forth in claim 8 including a rewind relay operable to back feed said tape at above-normal speed and a fast-forward relay operable to advance said tape at above-normal speed, and means for disabling both said rewind and fast-forward relays when said control signal relay is dropped out.
Claim 12
Dependent Claim
63 words
The dictating machine set forth in claim 8 wherein said control signal head includes a second head section positioned in rear of the first section energized by said control signal relay when the machine is in record condition for recording a control signal over the erased section of the control track left on the control track when said playback relay was dropped out.
Claim 13
Dependent Claim
81 words
The dictating machine set forth in claim 9 including a normal forward relay causing said tape to be advanced at normal speed when the normal forward relay is operated, means responsive to closing said manual playback control while the machine is in playback for operating said rewind relay durIng the time said playback control is held operated and said signal control relay is operated, and means responsive to operation of said rewind relay for disabling said normal forward and fast-forward relays.
Claim 14
Dependent Claim
47 words
The dictating machine set forth in claim 11 wherein the tape is returned to normal forward drive when said playback control is released, including means to maintain said playback relay operated during the reversal of the drive of the tape from fast rewind to normal forward drive.
Claim 15
Dependent Claim
68 words
The dictating machine set forth in claim 9 including a capacitor effective upon discharge through said playback relay to produce said delay in the drop out of the playback relay, a charge circuit for said capacitor enabled by operation of said rewind relay and by drop out of both said fast-forward and rewind relays, and means for completing said charge circuit by operation of said control signal relay.
Claim 16
Dependent Claim
57 words
The dictating machine set forth in claim 13 including a discharge circuit for said capacitor through said playback relay enabled by drop out of said control signal relay, and means for completing said discharge circuit by operation of said rewind relay and by a concurrent drop out of both said rewind relay and of said fast-forward relay.
Claim 17
Dependent Claim
94 words
The dictating machine set forth in claim 9 including means responsive to drop out of said signal control relay when an erased space is reached for dropping out said rewind relay to stop the reverse drive of the tape, means controlled by said rewind relay to restart the drive of the tape in a forward direction when said rewind relay is dropped out and before said playback relay is dropped out, and means responsive to reactivation of said control signal relay during the forward advance of the tape for maintaining said playback relay operated.
Claim 18
Dependent Claim
115 words
The dictating machine set forth in claim 9 including a normal forward relay for causing the tape to be advanced at normal speed when the relay is operated, means responsive to operating said manual record control while the machine is in playback for operating said fast-forward relay to advance the tape at fast speed, means responsive to holding said manual record control operated when said forward erased marker section is reached for producing a delayed drop out of said playback relay, and means responsive to drop out of said playback relay for operating said normal forward relay to start advance of the tape at normal speed and for concurrently shifting said machine into record condition.
Claim 19
Dependent Claim
145 words
The dictating machine set forth in claim 9 including an adjacent transcribing station cooperating with the tape, an on-off station switch, means responsive to shifting said on-off switch to off position while the machine is in playback condition for operating said fast-forward relay to advance the tape at fast speed while holding the playback relay operated until the forward erase marker space is reached, a multivibrator, means responsive to drop out of said playback relay when said marker section is reached for triggering said multivibrator for a preset interval, and circuit means operative while said multivibrator is triggered for applying dc erase current to both of said heads and for maintaining said fast-forward relay operated for said predetermined interval to provide an erased space along the tape of a length equal to the length of the tape from said recorder heads to said transcribing station.
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) | 1976-04-16 | 1976-10-16 | 1977-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-16 | 1980-10-16 | 1981-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-16 | 1984-10-16 | 1985-04-17 | $7700.00 | Window Closed / Lapsed |