JP2749352B2 - Magnetic recording / reproducing device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus having a rotary head.

2. Description of the Related Art In recent years, magnetic recording and reproducing devices such as VTRs have
In addition to multi-functionalization such as audio, outdoor magnetic recording / reproducing devices and the like are required to have a clogging check function of a rotary head in a smaller and thinner form.

Hereinafter, the conventional magnetic recording / reproducing apparatus will be described with reference to the drawings.

7 and 8 are a plan view of a rotary head mechanism of a conventional magnetic recording / reproducing apparatus and a connection diagram of a rotary head unit, respectively. Signals recorded by a pair of opposed recording heads 2a, 2b provided on the rotating drum 1 are read by a pair of opposed reproducing heads 3a, 3b also provided on the rotating drum 1, and the signals of the rotating transformer 4 and the rotating transformer Coil 5a, 6
After being amplified by the reproduction amplifiers 7a and 7b through a, 5b and 6b, for example, a VTR is processed as a video signal. With this configuration, if a trouble such as clogging occurs in the recording heads 2a and 2b during recording, the signal is immediately read by the reproducing heads 3a and 3b. Abnormality can be detected.

However, in the conventional configuration as described above, the coils 5a, 5a,
Since 6a, 5b, and 6b are required, a head for monitoring clogging should be provided in addition to a wide variety of specifications such as a head dedicated to recent standard mode and long recording mode, an FM audio head, a flying race head, and a head for special reproduction. However, there is a problem that the number of coils of the rotary transformer 4 is increased, which is an adverse effect of downsizing and thinning, and that the crosstalk characteristics of the rotary transformer 4 are deteriorated and the cost is increased.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a magnetic recording / reproducing apparatus in which a function of monitoring a recording signal such as detection of clogging of a recording head and the like is easily realized with a small number of channels.

Means for Solving the Problems In order to solve the above problems, a magnetic recording / reproducing apparatus according to the present invention comprises a rotating head mechanism for recording / reproducing, a rotating transformer for transmitting signals, and a pair of opposed azimuth angles different from each other. A recording head and a pair of adjacent reproducing heads having different azimuth angles are provided, and the reproducing heads are connected in series and connected to the same coil of the rotary transformer.

Operation According to the above configuration, a pair of adjacently arranged reproducing heads having different azimuth angles are connected in series and connected to the same coil of a rotary transformer, and a reproduction signal level of the reproducing head is monitored. By monitoring that the reproduction signal level of the reproduction head decreases when one of them becomes clogged, it is possible to monitor a recording signal such as detection of clogging of the recording head.

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

FIG. 1 is a plan view of a rotary head mechanism of a magnetic recording / reproducing apparatus showing one embodiment of the present invention, FIG. 2 is a sectional view of the rotary head mechanism, and FIG. 3 is a connection diagram of a rotary head unit.

The rotating drum 11 is provided with a pair of opposed recording / reproducing heads 12a, 12b having different azimuth angles and a pair of adjacent reproducing heads 13a, 13b having different azimuth angles. The drum 11 is fixed by screws, and is rotatably held on a fixed drum 16 via a disk 14, a shaft 15, and bearings 17a and 17b. The rotating transformer 18 on the rotating side is fixed to the disk 14 by a known method such as bonding, and the rotating transformer 19 on the fixed side is also fixed to the fixed drum 16, and they are opposed to each other via an appropriate gap. The recording / reproducing heads 12a, 1
2b signal transmission coils 20 and 21 (a pair on the fixed side and the rotation side) and the reproduction heads 13a and 13b signal transmission coils 22a and 2b.
2b are provided, and the reproducing heads 13a and 13b are connected in series, respectively.
Connected to a. The reproduction signals of the reproduction heads 13a and 13b are
The signal is transmitted to the reproducing amplifier 23 via the coils 22a and 22b, amplified, and compared with a reference level arbitrarily set by the battery 25 via the clamp circuit 24 by the level comparator 26.

FIG. 4 is an enlarged view of a track portion of the reproducing heads 13a and 13b. The reproduction heads 13a and 13b are recording and reproduction heads 12a and 12b.
In order to detect both fields of the recorded signal, the track width TW1 is set to a track width approximately twice as large as the track width of the recording / reproducing heads 12a and 12b.

The operation of monitoring the recorded signals of the recording / reproducing heads 12a, 12b by the reproducing heads 13a, 13b will be described. FIG. 6 shows the reproducing heads 13a, 13 amplified by the reproducing amplifier 24.
13 shows an envelope waveform of the reproduced signal b. In FIG. 6, if the signal from the reproducing head 13a is R and the signal from the reproducing head 13b is L, an L + R signal usually appears in one field, and the output of one field is zero. If the recording / reproducing head 12b becomes clogged, its envelope waveform becomes a waveform of only the signal R as shown in FIG. 6, and a level difference of 6 dB occurs. This signal is compared with a reference level arbitrarily set by the battery 15 by the clamp circuit 14 and the level comparator 16, and when the signal level is lower than the reference level, for example, an alarm lamp is turned on (not shown). ) And other means for recording and reproducing heads 12a, 12b
To inform you of the clogging.

Thus, the rotary transformers 18 and 19 for signal transmission
And a pair of opposed recording / reproducing heads 12a, 12b having different azimuth angles and a pair of adjacently disposed reproducing heads 13a, 13b having different azimuth angles are provided, and the reproducing heads 13a, 13b are respectively connected in series. The connection and the connection to the same coil 22a of the rotary transformer 18 make it possible to easily realize a recording signal instantaneous monitoring function such as detection of clogging of the recording / reproducing heads 12a and 12b with a small number of channels.

In FIG. 4, the track width of the reproducing heads 13a and 13b is about twice the track width of the recording and reproducing heads 12a and 12b. However, as shown in FIG.
The head may have a track width TW2 substantially equal to b and a difference in track height corresponding to the track pitch of the recording signal.

As described above, according to the present invention, a rotary transformer for signal transmission, a pair of opposed recording heads having different azimuth angles, and a pair of adjacently arranged reproducing heads having different azimuth angles are provided. By connecting the read heads in series and connecting them to the same coil of the rotary transformer, it is possible to realize an immediate monitoring function of a recording signal such as detection of clogging of a recording head with a small number of channels. Therefore, the function and performance can be improved by coping with multiple heads, or the rotary head device can be made smaller, thinner and embodied by reducing the number of channels.

[Brief description of the drawings]

1 to 6 show an embodiment of the magnetic recording and reproducing apparatus of the present invention. FIG. 1 is a plan view of a rotary head mechanism, and FIG.
FIG. 3 is a cross-sectional view of the rotary head mechanism, FIG. 3 is a connection portion of the rotary head section, FIGS. 4 and 5 are enlarged views of the read head track section, respectively, and FIG. 6 is a view of the read head amplified by the read amplifier. FIG. 3 is an envelope waveform diagram of a reproduction signal. 7 and 8 are a plan view of a rotary head mechanism of a conventional magnetic recording and reproducing apparatus and a connection diagram of a rotary head unit, respectively. 11… Rotary drum, 12a, 12b …… Recording / reproducing head, 13a, 1
3b: playback head, 16: fixed drum, 18, 19: rotary transformer, 22a, 22b: rotary transformer coil for playback head.

 ──────────────────────────────────────────────────続 き Continued from the front page (56) References JP-A-61-63985 (JP, A) JP-A-59-60724 (JP, U) JP-A-62-120486 (JP, U) JP-A-61-120486 162192 (JP, U)

Claims (3)

(57) [Claims] 1. A rotary head mechanism for recording / reproducing, a rotary transformer for transmitting a signal, a pair of opposed recording heads having different azimuth angles, and a pair of adjacent recording heads having different azimuth angles. A magnetic recording / reproducing apparatus, wherein the reproducing heads are connected to the same coil of the rotary transformer. 2. The recording head according to claim 1, wherein each of the adjacent reproducing heads has a track width approximately twice that of the recording head.
The magnetic recording and reproducing apparatus according to claim 1. 3. The magnetic recording apparatus according to claim 1, wherein adjacent reproducing heads have a track width substantially equal to that of the recording head and a difference in height corresponding to a recording track pitch between the reproducing heads. Playback device.