JPH01178158A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To prevent the erroneous recording of a magnetic recording medium by discriminating the presence or absence of the signal transmitted from a wrong recording preventing means and prohibiting a new recording onto the magnetic recording medium in which a recording preventing signal is recorded by a recording control means at the time when a wrong recording preventing signal is detected. CONSTITUTION:A wrong recording preventing signal 14 is recorded on the control track 3c of a magnetic tape 3 corresponding to wrong recording preventing parts 31-33. This wrong recording preventing signal 14 is read by a reading head 9 and after being pulled out by a high pass filter 10 it is processed by a wrong recording preventing signal processing circuit 12 and fed out to a recording control circuit 13. The recording control circuit 13 decides as to whether the recording is prohibited or not by discriminating the presence or absence of the signal 14 fed from the processing circuit 12 and in case of judging the presence of the signal the recording is prohibited by the control signal 15 for prohibiting recording. The recording contents of the wrong recording preventing part in the magnetic tape can thus be reserved without being recorded wrongly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic recording and reproducing device applied to video tape recorders (hereinafter referred to as VTRs) and the like.

[Conventional technology]

Figure 5 shows a conventional device of this kind, for example, a VH8 system VT.
FIG. 2 is a perspective view schematically showing a cassette used for R.

In the figure, (1) is a cassette in which a magnetic tape (not shown) is housed as a magnetic recording medium. (2) is a claw piece formed at a predetermined location of the cassette (1) to prevent erroneous recording.

In this case, erroneous recording means newly recording on a previously recorded portion of the magnetic tape.

Next, the operation will be explained.

When recording on a magnetic tape, do not break the claw piece (2) for preventing erroneous recording, and insert the cassette (1) into the V (not shown).
When inserted into the TR and set to recording mode, recording operations can be performed. To prevent erroneous recording, break the claw piece (2). In this case, since the claw piece (2) is broken, the VTR determines that recording of the cassette (1) is prohibited, and becomes in a recording prohibited state. At this time, the VTR detects recording prohibition by determining the presence or absence of the above-mentioned claw (2). Conventional magnetic recording and reproducing devices are configured as described above, so they record up to the middle of the magnetic tape, and then If you want to record on the magnetic tape, you cannot break the claw piece (2) for preventing erroneous recording, and therefore you may accidentally record on the already recorded part of the magnetic tape.

In addition, if the claw piece (2) is broken to protect the recording up to the middle of the magnetic tape, it will no longer be possible to record on the unrecorded portion of the magnetic tape. cannot be used effectively. These problems arise because prevention of erroneous recording on the magnetic tape is performed on a cassette-by-cassette basis.

The present invention has been made in order to solve the problems of the above-mentioned conventional devices, and provides a magnetic recording and reproducing device that can prevent erroneous recording on any part of a magnetic recording medium. An erroneous recording prevention signal detection means for detecting an erroneous recording prevention signal recorded on a medium, and a recording control means for determining whether or not to prohibit recording in a recording mode by determining the presence or absence of a signal from the detection means. It was established.

[Effect]

In the magnetic recording/reproducing apparatus according to the present invention, when an erroneous recording prevention signal of the magnetic recording medium is detected in the recording mode, an output from the recording control means is used to record a new magnetic recording medium on which the erroneous recording prevention signal is recorded. Recording will no longer be possible.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of the main parts of a VTR to which a magnetic recording/reproducing device according to the present invention is applied, and FIG. 2 shows a magnetic tape as a magnetic recording medium housed in a cassette used in the device. FIG.

In the figure, (3) is a magnetic tape, which has an audio track (8a), a video track (8b), and a condolence hook (8c). , control signal (
Signal (5) in which an error recording prevention signal is superimposed on Fig. 8 (A))
(Fig. 8(B)) is recorded.

(6) Control head)', (7) Control signal from the output signal from control head (6)
(8) is a control signal amplification circuit connected to the low-pass filter (7).

(9) is a full-width erase head (
(not shown) is an erroneous recording prevention signal reading head provided at the rear. αα is a bypass filter that is connected to the reading head (9) and extracts the erroneous recording prevention signal superimposed on the control pulse (4), and together with the reading head (9) constitutes a circle of erroneous recording prevention signal detection means. are doing. (2) is an erroneous recording prevention signal processing circuit connected to the bypass filter α0, and (2) determines whether or not there is an output signal from the processing circuit @ to determine whether or not to prohibit recording in the recording mode. This is a recording control circuit.

Next, the operation of the above configuration will be explained.

The control track (8c) of the magnetic tape (3) has, for example, an erroneous recording prevention portion (9) shown in FIG. 4(A).

(2) Corresponding to c131, an erroneous recording prevention signal Q41 shown in FIG. 4(B) is recorded. The erroneous recording prevention signal α small is read by the reading head (9), and the bypass filter μ (
10. Since the erroneous recording prevention signal αa is superimposed on the control signal (4) as shown in FIG. 8(B), it is extracted by the bypass filter α0 and then processed by the erroneous recording prevention signal processing circuit Sent to control circuit ■. The recording control circuit side determines whether or not to inhibit recording by determining the presence or absence of the signal α from the processing circuit port. When it is determined that there is a signal, a control signal for inhibiting recording is sent to the recording unit (not shown), and the
Recording is prohibited.

That is, the recorded contents of the erroneous recording prevention portions (11), +321, (to) on the magnetic tape (3) are saved without being erroneously recorded. Moreover, magnetic tape (
Regarding the unrecorded portion (material) and (material) of 3), new recording can be made, and the magnetic tape (3) can be used effectively.

In the above embodiment, an example was explained in which the erroneous recording prevention signal α was recorded on the control track (8C) of the magnetic tape (3). It has the same effect as the example.

[Brief explanation of the drawing]

FIG. 1 shows a magnetic recording/reproducing apparatus according to the present invention.
A) and (B) are diagrams showing a control signal and a signal in which an error recording prevention signal is superimposed on the control signal, respectively. FIG. 5 is a perspective view schematically showing a cassette for preventing erroneous recording in a conventional magnetic recording/reproducing apparatus. Co., Ltd.: Erroneous recording prevention signal detection means, αJ: Recording control order. In the drawings, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] (1) An erroneous recording prevention signal detection means for detecting an erroneous recording prevention signal recorded on a magnetic recording medium, and determining whether or not to prohibit recording in the recording mode by determining the presence or absence of a signal from this detection means. What is claimed is: 1. A magnetic recording and reproducing device comprising a recording control means for controlling