JPH0550537U - Magnetic recording / reproducing device - Google Patents

Abstract

(57) [Abstract] [Purpose] An object of the present invention is to provide an overwriting prevention device which can notify the user in advance even if the erasing nail is forgotten and prevent erroneous erasing. A detection head for outputting a signal on a magnetic tape to a control device in a recording mode is provided in the tape running path closer to the cassette tape outlet than the erasing head. Further, it is provided with means for issuing a warning based on the presence or absence of a signal detected by the detection head. Further, means for controlling the running of the tape by the above signal is provided.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a magnetic recording / reproducing device. The recording / reproducing apparatus according to the present invention includes any recording / reproducing apparatus that uses a magnetic tape, such as an audio tape recorder and a video tape recorder.

[0002]

[Prior Art]

 A conventional structure for preventing repeated recording will be described with reference to the drawings.

In FIG. 6, the video cassette tape (1) is composed of a cassette body (102) and a cassette lid (103), and the tape remaining amount on the upper surface of the video cassette tape (1) is seen from the outside. Windows (104) (104) are provided for this purpose. Further, an erroneous erasure prevention claw (105) for preventing erroneous erasure of recorded contents is provided on the back surface (opposite side of the cassette lid (103)) of the video cassette tape (1).

Then, in order to prevent erroneous erasure, the erroneous erasure prevention claw (105) is folded and used.

[0005]

[Problems to be solved by the device]

 However, in the above-mentioned conventional erroneous erasure prevention structure, when the information is recorded on the cassette tape, the erroneous erasure prevention claw is often forgotten, and there is a drawback that the information is erroneously erased. Furthermore, once the accidental erasure prevention nail is broken, there is a drawback that very difficult work is required, such as attaching a substitute for the accidental erasure prevention nail when it is desired to record again.

Therefore, the present invention has been made in consideration of the above circumstances, and a device that can prevent erroneous erasure by letting the user know that overwriting is performed even when the erroneous erasure prevention nail is forgotten. It is intended to provide a storage device.

[0007]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention is characterized in that a signal detection head for taking out a signal on a magnetic tape to a control position in a recording mode is provided in a tape running path closer to the tape outlet of the cassette than the erasing head. It is what Further, it is characterized in that it is provided with a means for issuing a warning based on the presence or absence of a signal detected by the signal detection head. Further, it is characterized in that means for controlling the running of the tape by the above-mentioned signal is provided.

[0008]

【Example】

 A preferred embodiment of the overwriting prevention device of the present invention will be described below with reference to the drawings.

FIG. 1 is an electrical block diagram of the overwriting prevention apparatus according to the present embodiment, FIG. 2 is a flow chart showing the operation for preventing overlap recording, and FIG. 3 is a view showing the magnetic tape surface. Is.

Reference numeral (1) is a video tape. Generally, when recording on a magnetic tape (2), the magnetic tape (2) advances in a fixed direction (arrow A in FIG. 1), and first, on the erasing head (3). When the magnetic tape (2) contacts, the previously recorded content (signal) is erased. The rotary drum (4) is provided with a main signal recording head, that is, an audio recording head (5) and a video recording head (6), and the audio recording head (5) and the video recording head (6) are magnetized. By contacting the tape (2), the audio signal (7) and the video signal (8) are recorded on the magnetic tape (2). Next, the control signal (10) is recorded on the magnetic tape (2) by contacting the magnetic tape (2) with the control signal recording head (9) (hereinafter referred to as CTL head). Furthermore, the audio signal (7) is recorded via the rotary head (5a) and simultaneously on the tape via the fixed head (5b) adjacent to the CTL head (9).

In order to prevent repeated recording, a signal detection head (11) is provided on the running path on the tape ejection side of the cassette with respect to the erasing head (3). The signal detected by the signal detection head (11) is sent to the signal detection unit (13) provided inside the microcomputer (12) for controlling the video tape recorder, and the signal (video signal (8), audio signal The signal (7), the control signal (10), etc. are recognized and transmitted to the CPU (central processing unit) (14). The CPU then issues a control signal to the warning means and a warning is issued to the user.

Further, in order to distinguish the above-mentioned signal from noise, a certain detection time is set so that each signal of video, audio, and control can be recognized at the time of detection, and erasing does not start. This makes it possible to prevent false alarms from being caused by erroneously recognizing noise as a signal. That is, the constant detection time at which each signal can be recognized and the erasing does not start depends on the distance between the signal detecting head (11) and the erasing head (3). For example, the tape speed of a VHS video tape recorder is 3.33 cm / s. If not noise, the minimum unit time (for example, 0.5 seconds) that constitutes the control signal is required. Therefore, the distance between the signal detecting head (11) and the erasing head (3) must be at least 1.67 cm. Similarly, for video tape recorders with different tape speeds, the proper distance can be obtained by the product of the distance per second and the time when noise is recognized.

The signals have been described in the contents of the video signal (8), the audio signal (7) and the control signal (10), but among them, the control signal (10) is the signal that is most easily detected. That is, the control signal (10) is always recorded over the entire length of the magnetic tape even in the portion where the audio signal (7) or the video signal (8) is not recorded on the recorded tape.

The warning means may be any warning means as long as it can notify the user. For example, the warning lamp (19), the warning buzzer (20), the OSD display (21) displayed on the screen, and the ROM (17) store the warning message and display the message on the liquid crystal screen at the time of warning ( There is a liquid crystal display (22) and the like.

Next, the operation of this embodiment will be described with reference to FIGS. 1 and 2. First, a cassette is inserted (S1), it is determined whether or not a claw for preventing erroneous erasure is present (S2), and if not, the reproducing operation (S3) is performed as it is. If yes, recording and reproduction are selected (S4), if reproduction is performed, reproduction operation (S3) is performed, and in the case of recording, the signal is detected by the signal detection head (11) (S5), and the microcomputer (12) ) Is sent (S6). Then, the presence / absence of a signal is determined (S7), and if there is no signal, the normal recording operation is performed (S8). If the signal is present, the user is informed by a warning lamp or a warning buzzer (S9), The operation is performed (S8).

The preferred embodiment of the present invention has been described above in detail, but it is obvious that various modifications can be made without departing from the scope of the present invention.

For example, in the above-mentioned contents, the recording operation or the recording operation is performed as usual even when the user is notified of the overwriting warning. However, for example, the changeover switch (23) is provided. Of course, it is possible to stop the tape running at the time of warning.

That is, as shown in FIG. 4, a changeover switch (23) for moving or stopping the tape is provided, and a tape drive control circuit (24) and a rotary head drive are provided inside the microcomputer (12). Since the control circuit (25) is provided, the tape can be stopped or run by turning on / off the changeover switch (23).

Next, the operation of the above-described second embodiment will be described with reference to FIG.

First, a cassette tape is inserted (T1), it is determined whether or not the erroneous erasure prevention claw is present (T2), and if it is not present, the reproducing operation (T3) is performed as it is. If it is present, it is judged whether or not to record (T4), and if it is not recorded, the reproducing operation (T3) is performed as it is. When recording, the signal is detected by the signal detection head (11) (T5) and sent to the micro computer (12) (T6). Then, the presence / absence of the signal is judged (T7), and if it is not present, the normal recording operation is carried out (T8), and if it is present, the user is informed by a warning lamp or a warning buzzer (T9). At that time, it is judged whether the changeover switch (23) for stopping or running the tape is ON / OFF (T10), and if it is OFF, the tape is run (T8). In addition, when it is ON, the structure is such that the tape running is stopped (T11).

As described above, according to the first embodiment, even if the mistaken erasure prevention claw (105) of the cassette tape is forgotten to be folded, the user can be notified by a warning means such as a lamp or a buzzer by detecting the already recorded signal. It becomes possible to notify and prevent erroneous deletion.

Further, according to the second embodiment, the user can be notified by the warning means, and the tape can be run and stopped by turning the switching switch (22) ON / OFF.

[0023]

[Effect of the device]

 As described above in detail, according to the present invention, even if the erroneous erasure prevention tab of the cassette tape or the like is forgotten, the signal already recorded is detected and the user is warned in advance. By notifying, it becomes possible to prevent erroneous erasure. Further, by providing the changeover switch, the user can select the tape running / stopping, which improves the convenience of the user.

[Brief description of drawings]

FIG. 1 is a block diagram of an overwriting prevention device using a first embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the overwriting prevention device using the first embodiment of the present invention.

FIG. 3 is a diagram showing signals recorded on a magnetic tape.

FIG. 4 is a block diagram of an overwriting prevention device using a second embodiment of the present invention.

FIG. 5 is a flowchart showing the operation of the overwriting prevention device using the second embodiment of the present invention.

FIG. 6 is a perspective view of a video tape.

[Explanation of symbols]

 (11) Signal detection head (12) Microcomputer (19) (20) (21) (22) Warning means

Claims (3)

[Scope of utility model registration request] 1. A main signal recording head is attached to a rotary cylinder, an erasing head is attached to a tape running path between the rotary cylinder and a cassette tape outlet, and a control signal recording head is attached to the rotary cylinder and a cassette tape. A magnetic recording / reproducing apparatus mounted on a tape traveling path between a storage port and a storage port, wherein a signal detection head is provided on a tape traveling path between the tape ejecting port and the erasing head. 2. The magnetic recording / reproducing apparatus according to claim 1, further comprising means for issuing a warning based on the presence / absence of a signal detected by the signal detecting head. 3. The magnetic recording / reproducing apparatus according to claim 1 or 2, further comprising means for controlling the running of the tape by the signal.