JPH0448464A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To optimize the contact condition of a magnetic tape and a magnetic head by feeding back so that the reproduced waveform of a reference signal recorded on the magnetic tape may become the good reproduced waveform and changing the tension of the magnetic tape by controlling the inclined angle of a post automatically. CONSTITUTION:A reproduced waveform 301 obtained when a reference signal from a reference signal generator 10 is recorded and reproduced on a magnetic tape 4 is detected by a reproduced envelope waveform comparing circuit 11 and compared with an ideal reproduced waveform 300. A control signal set in advance in a feedback discriminating circuit 12 is transferred to a post inclination mechanism 14 by the difference of a compared pattern. The post inclination mechanism 14 makes a post 2 inclined by the control signal. Then, since the width directional tension of the magnetic tape 4 changes and the magnetic tape 4 is displaced simultaneously, the displacement of it is detected by a tape displacement measuring device 13 and is transferred to the feedback discriminating circuit 12. thus, the contact of the magnetic tape 4 and the magnetic head 5 becomes optimum.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a magnetic recording/reproducing device.

[Conventional technology]

Conventionally, in a magnetic recording/reproducing apparatus, it is well known that in order to maintain good contact between the magnetic head and the magnetic tape at the entrance and exit of a drum, an inclination is applied in advance as a bias to posts near the entrance and exit. This inclination changes the tension of the tape, increases the contact pressure between the magnetic tape and the magnetic head, and enables good recording and reproduction. However, it was difficult to set the slope in advance.

[Problem to be solved by the invention]

The conventional magnetic recording and reproducing bag mentioned above! In this case, the posts near the entrance and exit of the drum were tilted to maintain good contact between the magnetic head and the magnetic tape.
Setting this inclination is difficult; if the inclination angle is too large, the tape will be displaced upward or downward and the tape edge will be damaged by the flange of the post, etc.; if the inclination angle is too small, it will maintain good contact pressure. There were drawbacks such as ineffectiveness.

[Means to solve the problem]

The magnetic recording and reproducing apparatus of the present invention includes a reference signal generator that generates a reference signal to be recorded on a magnetic tape, and a reproduction envelope waveform comparison circuit that captures the reproduction signal of the reference signal as a waveform and compares it with a good reproduction signal shape. , a feedback determination circuit that transmits tilt change data to the post tilting mechanism based on the comparison result, and the post tilting mechanism that tilts the post.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing the overall configuration of an embodiment of the magnetic recording/reproducing apparatus of the present invention, and FIG. 3 is a diagram showing reproduction waveforms according to this embodiment.

In FIG. 1, a magnetic tape 4 is wound around a drum 1,
Signals are recorded and reproduced by the magnetic head 5. A reproduced waveform 301 (FIG. 3) obtained when the reference signal from the reference signal generator 10 is recorded and reproduced on the magnetic tape 4 is detected by the reproduced envelope waveform comparison circuit 11, and an ideal reproduced waveform 300 (FIG. 3) is detected by the reproduced envelope waveform comparison circuit 11.
Figure). Based on the difference between the compared patterns, a preset control signal is transmitted to the feedback determination circuit 12 to the post tilt mechanism 14. This control signal causes the post tilting mechanism 14 to tilt the post 2.

FIG. 2 is a cutaway perspective view showing an example of the post tilting mechanism shown in FIG. The slope changes. Here, the piezoelectric element 142 is fixed by a fixing member 144 with a screw 145, and the tension of the inclined post 2 is controlled by a tab 146.

In this way, the tension in the width direction of the magnetic tape 4 changes and at the same time the magnetic tape 4 is displaced. This displacement is detected by the tape displacement measuring device 13 and transmitted to the feedback determination circuit 12. When the magnetic tape 4 is about to be displaced relative to the upper flange of the guide flange 6 due to the position 1 of the tape edge, the movement of the post tilting device 14 is controlled to prevent damage to the tape edge. Furthermore, the envelope waveform is monitored by the reproduced envelope waveform comparison circuit 11, and the tilt post 2 is tilted until it approaches the ideal reproduced waveform 300.

〔Effect of the invention〕

As explained above, the present invention feeds back the reproduced waveform of the reference signal recorded on the magnetic tape to obtain a good reproduced waveform, automatically controls the inclination angle of the post, and changes the tension of the magnetic tape. Therefore, it is possible to optimize the contact state between the magnetic tape and the magnetic head.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the overall configuration of an embodiment of the magnetic recording/reproducing apparatus of the present invention, FIG. 2 is a cutaway perspective view showing an example of the post tilting mechanism in FIG. 1, and FIG. 3 is similar to FIG. 1. FIG. 6 is a diagram showing a reproduced waveform according to the illustrated embodiment. DESCRIPTION OF SYMBOLS 1... Drum, 2... Inclined post, 3... Guide post, 4... Magnetic tape, 5... Magnetic head, 6
... Guide flange, 10 ... Reference signal generator, 1
DESCRIPTION OF SYMBOLS 1... Reproduction envelope waveform comparison circuit, 12... Feedback determination circuit, 13... Tape displacement measuring device, 14... Post tilting mechanism, 142... Piezoelectric element,
143...Fixing rod, 144...Fixing tool, 145
...Screw, 146...Spring, 300...Ideal reproduced waveform, 301...Regenerated waveform.

Claims (1)

[Claims] A magnetic recording and reproducing apparatus comprising a recording and reproducing head for recording and reproducing signals on a magnetic tape, a recording and reproducing circuit, and a magnetic tape running mechanism, a reference signal generator that generates a reference signal to be recorded on the magnetic tape, and a reference signal generator that generates a reference signal to be recorded on the magnetic tape; a reproduction envelope waveform comparison circuit that captures a reproduced signal as a waveform and compares it with a good reproduction signal shape; a feedback judgment circuit that transmits tilt change data to the post tilt mechanism based on the comparison result; and the post tilt mechanism that tilts the post. A magnetic recording and reproducing device comprising: