JPS5824271Y2 - magnetic recording and reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic recording/reproducing device, and particularly to improvements in its auto-reverse system.

Some conventional open-type or cassette deck-type tape recorders use an auto-reverse method, but these methods include manual control, detection of metal foil pasted on the magnetic tape, or mechanical method. There are B, E, and A (before-end alarm) methods by detection.

However, both methods have problems, such as requiring cumbersome work such as the need to attach metal foil to a predetermined position on the magnetic tape in advance.

In order to improve the problems of the prior art, the present invention uses an auto-reverse mode to detect the presence or absence of an audio signal near the end of the tape, and reverses the tape when the audio signal is interrupted or a predetermined period of time has elapsed. A before-end alarm or a predetermined control signal is issued at the end of the tape after reversal, and before the tape is reversed,
The present invention is characterized in that the tracks on both sides of B are erased at the same time.

The present invention will be described below with reference to embodiments shown in the drawings.
1, 1 and 2 are reels, 3 is a recording/playback head, 4 is an erasing head, 5 and 6 are capstans, respectively.
7 and 8 are pinch rollers, 9 and 10 are reels 1 and 2
11 is a switching device consisting of a plunger and the like.

The outputs of the detectors 9 and 10 are applied to a tape position detection circuit 12, which detects that the magnetic tape 13 has reached the last position (address) of its A or 8th track.

The tape position detector 12 is, for example, disclosed in Japanese Utility Model Application No. 51-16088.
The configuration described in No. 3, that is, the sum or difference of the rotation speeds of reels 1 and 2, divided by the rotation speed of the reel with the higher rotation speed, is proportional to the time. The magnetic tape 13 is arbitrarily divided and assigned an address for processing.

14 is a circuit for detecting interruptions in recording input; 15 is a circuit for detecting interruptions in playback output; 16 is a timing circuit;
Even if recording input or playback output is not interrupted, a timing signal is generated when a certain period of time has elapsed after reaching the last address on the tape.

17 is a reverse control signal generation circuit, 18 is an auto-reverse mode signal generation circuit, 19 is a bias oscillator, 20
．． 20' is a recording/playback button, 21 is a playback amplifier, 22 is a speaker, 23, 24, 29 and 32 are switches, 25,
26 is an AND circuit, and 27 and 28 are OR circuits.

Note that 33 is a tape position display device including a running direction display means.

In the above-mentioned tape recorder according to the present invention (for convenience of explanation, it is assumed to be a monaural type),
In order to record the desired audio signal applied to the terminal 31 in the J-verse mode, when the auto-reverse button 30 and the record/play buttons 20 and 20' are turned on, the switch 23 is connected to the A-side track terminal of the recording/playback head 3. For example, the pinch roller 7 is selected, and the switch 24 is turned on by an auto-reverse mode signal from the circuit 18, and the switch 29 is turned on in conjunction with the recording button 20.

Therefore, the bias oscillator 19 operates and its oscillation output is sent to the A and B track terminals A of the erasing head 4.

Since the A and 8th side tracks of the magnetic tape 13 are simultaneously erased, recording is performed on the A side track.

When the last address of the A-side track is reached, this is detected by the tape position detection circuit 12, and its detection output is given to the AND circuit 25 and the timing circuit 16.

At this time, if the recording input is interrupted, the circuit 14 detects this and provides its output to the AND circuit 25 via the OR circuit 28.

However, although it is better to auto-reverse after the audio signal is interrupted, if the recording input is interrupted even after a certain period of time, the auto-reverse is forced, so the output from the timing circuit 16 is connected to the OR circuit. 28 to the AND circuit 25.

Thus, when the AND circuit 25 generates an output, the AND output is given to the reverse control signal generating circuit 17, so that the circuit 17 generates a reverse control signal, which is applied to the AND circuit 26.

Since the AND circuit 26 is supplied with the auto-reverse mode signal from the circuit 18, the AND output switches the switch 23 to the B-side track terminal B and turns off the switch, causing the bias oscillator 19 to stop operating. The erase head 4 is stopped and the erase head 4 is deenergized.

Furthermore, the switching device 11 is actuated by the output of the AND circuit 26, and the pinch roller 7 is switched to the pinch roller 8, so that recording is performed on the 8th track.

When the magnetic tape 13 reaches the last address of the 8th track,
The tape position detection circuit 12 provides a before-end alarm (BEA) to an alarm device 33, or the control signal generation circuit 34 provides a control signal C to another device (for example, a second tape recorder, not shown). .

Note that 35 is an OR circuit, and 36 is an AND circuit.

This control signal C is used, for example, as a switching control signal for continuous recording with two or more tape recorders.

Alternatively, a cue signal may be recorded in advance at the position of the button magnetic tape 13 immediately before auto-reverse is activated, the cue signal may be detected during playback, and auto-reverse may be activated by the detection signal.

It goes without saying that the present invention can also be applied to stereo type tape recorders.

When the auto-reverse button 30 is not turned on, the switch 24 is turned off, so the erasing head 4 operates to erase only one track, and even if the BEA is output at the last address of the track on either side. good.

As explained above, according to the present invention, the A side and the 8th side of the tape
It is possible to record continuously for a long time without interrupting surface tracks, and not only can the BEA function effectively, but also the erasing head is A.

B: Since both sides are erased at the same time, it saves money.

BRIEF DESCRIPTION OF THE DRAWINGS The figure is a block diagram showing an embodiment of the present invention. 1.2...Reel, 3...Recording/playback head, 4...
・Erasing head, 5, 6... Capstan, 7, 8...
- Pinch roller, 12...Tape position detection circuit.

Claims (1)

[Scope of utility model registration request] In the auto-reverse mode, a first detection section that detects the presence or absence of an audio signal of the recording input or tape playback output and detects that the audio signal is interrupted, and a second detection section that detects the number of rotations of the reel. a timing circuit for outputting the output of the second detection section after a predetermined period of time; and a timing in response to the output of the timing circuit or the output of the first detection section and the output of the second detection section. A logic circuit configured to drive a reverse control signal generation circuit, and the reverse control signal generation circuit reverse the running direction of the tape, switch the track of the recording/playback head, and when the tape is near the end after the reversal, the second The output of the detection section determines the before and end results.
When an alarm is issued and before the above reversal, a bias oscillation output is given to simultaneously erase tracks on both sides A and B of the tape by a switch linked to the recording operation, and after the above reversal, the reverse control signal generation circuit 1. A magnetic recording/reproducing device, comprising means for releasing the state of the switch.