Patent
Apparatus for reproducing information recorded in a plurality of adjacent tracks
| العنوان: | Apparatus for reproducing information recorded in a plurality of adjacent tracks |
|---|---|
| Patent Number: | 4,439,799 |
| تاريخ النشر: | March 27, 1984 |
| Appl. No: | 06/328,873 |
| Application Filed: | December 09, 1981 |
| مستخلص: | A reproducing apparatus for information signals recorded in inclined tracks together with tracking signals whose frequency changes from track to track in a cyclic sequence, comprises a variable-frequency signal generator for the generation of track selection signals, from which together with the crosstalk tracking signals reproduced during a playback mode by at least one rotatable playback head arranged on an electromechanical transducer a transducer actuating signal is derived for tracking purposes, by means of which actuating signal the transducer with the playback head is adjustable between two extreme positions transversely of the tracks. By means of an amplitude discriminator having two threshold values corresponding to the two amplitudes of the actuating signal for deflecting the transducer to its two extreme position, the actuating signal is detected and when the threshold values are exceeded an additional change-over of the track selection signal generation is initiated, which continues until the transducer can guide the playback head along the tracks without reaching one of its extreme positions. |
| Inventors: | Haubrich, Peter (Vienna, ATX); Hoogendoorn, Abraham (Vienna, ATX); Jahnke, Uwe (Vienna, ATX) |
| Assignees: | U.S. Philips Corporation (New York, NY) |
| Claim: | What is claimed is |
| Claim: | 1. An apparatus for reproducing information signals recorded on a record carrier in the form of a tape in inclined parallel tracks arranged adjacent each other, wherein together with said information signals tracking signals are recorded in said tracks, said tracking signals having a frequency which changes from track to track in a predetermined cyclic sequence, which apparatus comprises at least one rotatable playback head which, for following the tracks, is arranged on an electro-mechanical transducer, which head when scanning each track also reproduces tracking signals produced by cross talk from the two tracks adjacent the track being scanned, a position detector for detecting the rotary position of the head relative to the record carrier, which position detector supplies a position pulse and is connected to a pulse generator for generating control pulses associated with the position pulses, which control pulses are applied to a signal generator whose frequency is variable, which signal generator, depending on said control pulses, consecutively generators track selection signals whose frequency changes in the same cyclic sequence as the recorded tracking signals, a signal processing circuit which derives an actuating signal from said track selection signals and the reproduced crosstalk tracking signals, by means of which actuating signal the transducer carrying the playback head is adjustable between two extreme positions substantially transversely of the tracks, characterized in that there is provided at least one amplitude discriminator, means for supplying to said amplitude discriminator a signal which is proportional to the actuating signal for the transducer, said discriminator having two threshold values corresponding to the two amplitudes of the actuating signal which deflect the transducer to its two extreme positions, which discriminator supplies a switching signal when a threshold value is exceeded, which switching signal controls a further pulse generator which, depending on said switching signal, supplies pulses to said signal generator causing an additional change-over in the track selection signal generation. |
| Claim: | 2. A reproducing apparatus as claimed in claim 1, characterized in that two of said further pulse generators are provided and the amplitude discriminator is adapted to supply two switching signals each corresponding to one of the two threshold values, which switching signals each control a respective further pulse generator which in dependence on the switching signals supply pulses to the signal generator, said signal generator changing over the track selection signal generation according to said predetermined cyclic sequence in dependence on the pulses from one of the two further pulse generators, and in the reversed predetermined cyclic sequence in dependence on the pulses from the other of the two further pulse generators. |
| Claim: | 3. A reproducing apparatus as claimed in claim 2, characterized in that said apparatus comprises at least two playback heads each arranged on a transducer, and at least two amplitude discriminators each adapted to supply said two switching signals, the switching signals corresponding to the same threshold value together controlling a respective further pulse generator. |
| Claim: | 4. A reproducing apparatus as claimed in claim 1 or 2, characterized in that said apparatus comprises at least two playback heads, each arranged on one transducer, and there is provided a single amplitude discriminator, which receives a signal which is proportional to the actuating signals for all the transducers. |
| Claim: | 5. A reproducing apparatus as claimed in claims 1, 2 or 3, characterized in that the further pulse generator supplies consecutive pulses having a period which is at least equal to the period of time which has elapsed after the additional change-over to another track selection signal in order to derive the actuating signal from said track selection signal. |
| Current U.S. Class: | 360/77; 360/102; 360/70 |
| Current International Class: | G11B 558; G11B 2104 |
| Patent References Cited: | 4237500 December 1980 Sanderson |
| Primary Examiner: | Stellar, George G. |
| Attorney, Agent or Firm: | Briody, Thomas A. Mayer, Robert T. Tamoshunas, Algy |
| رقم الانضمام: | edspgr.04439799 |
| قاعدة البيانات: | USPTO Patent Grants |
| الوصف غير متاح. |