JP2510325B2 - Adjustment device for magnetic recording / reproducing device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adjusting device of a magnetic recording / reproducing apparatus for performing mechanical compatibility adjustment of a helical scanning type magnetic recording / reproducing apparatus used in a VTR or the like.

2. Description of the Related Art In recent years, recording / reproducing devices using magnetic recording have been widely used in VTRs and the like, and as a trend, due to an increase in signal amount due to digitization and the like, high speed rotation of head drum device,
Narrow tracks and tape-shaped recording media (hereinafter referred to as magnetic tapes) are becoming thinner. Under these circumstances, the mechanical issues include: 1) ensuring linearity 2) securing tape running stability 3) aging in order to ensure that the magnetic head correctly traces the recorded track and maintain compatibility between machines. Reduction of change 4) Reduction of environmental change, and efforts are being made to solve it.

Conventionally, adjustment of a magnetic recording / reproducing apparatus having this type of recording head and reproducing head has been performed as follows.

FIG. 3 shows an example of a head arrangement for performing 2CH divided recording. In FIG. 3, 1 is a rotary drum, 2 is a first flying erase head, 10 and 11 are first recording-only pair heads, 8 and 9 are first reproducing-only pair heads, and 7 is a second flying erase head. Reference numerals 5 and 6 are second recording-only pair heads, and 3 and 4 are first reproduction-only pair heads, and the azimuth directions between the pairs are opposite to each other. A signal is recorded on a magnetic tape (not shown) by this rotating drum 1.

Fig. 4 shows a pair of read-only pair heads 10, 11 or 5, 6 for recording on magnetic tape and a read-only pair head 8, 9 or 3, 4
It is a block diagram of the circuit reproduced by. The signal passes through the video signal processing circuit 12 and is amplified by the recording head amplifier 13, and the signal is recorded on the magnetic tape 14 by the recording-only pair head 10, 11 or 5, 6. Also, playback is magnetic tape
14 is reproduced and a signal is taken out from the magnetic tape 14 by the reproduction-only pair heads 8, 9 or 3, 4 and amplified by the reproduction head amplifier 15 and passed through the video signal processing circuit 16. At this time, if the reproduction output of the reproduction head amplifier 15 is confirmed by an oscilloscope connected to the detection terminal 17, it can be taken out as an envelope. If you use compatibility confirmation standard tape for magnetic tape 14,
Linearity can be measured from the flatness of the envelope.
This is shown in FIG. Here, 18 is an oscilloscope screen and 19 is an envelope.

Fig. 5 is a block diagram of a circuit that uses azimuth time difference detection to detect linearity. Because of the azimuth of the read-only pair heads 8, 9 or 3, 4, linearity is determined by using the time shift between pairs caused by track shift. It is something to measure. That is, the time difference detection circuit 20 connected to the video signal processing circuit 16 measures the time lag of the signal between the read-only pair heads 8 and 9 or 3 and 4, and the DA converter 21 sets the DA
Convert and output. This output is shown in FIG. Here, 22 is the detected linearity curve.

Conventionally, in ensuring the mechanical compatibility of a magnetic recording / reproducing apparatus, a compatibility confirmation standard tape is used, and the mechanical compatibility at the time of reproducing is used by using the envelope 19 or the linearity curve 22 of the reproducing head of the magnetic recording / reproducing apparatus. I've adjusted. That is, the oscilloscope screen 18 should be set so that the track deviation from the standard tape is within the specified standard.
This is done by mechanical adjusting means (not shown here) so that the upper envelope 19 or the linearity curve 22 has a predetermined shape.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the above-described conventional configuration, when adjusting the mechanical compatibility of the magnetic recording / reproducing apparatus, when viewed microscopically, the recording head and the reproducing head have a head mounting accuracy and a window. The relative positions of the recording head and the reproducing head with respect to the magnetic tape differ depending on the shape, the amount of buffing of the window, the rotation accuracy of the rotating drum, and the like. This situation is shown in the bitter diagram of FIG. Reference numeral 23 is a measurement point, 24 is a track deviation, 25 is a track deviation curve of the recording head, and 26 is a reproduction head track deviation curve when recording is experimentally performed by the reproduction head. For the above reason, the loci are different on the order of μm. That is, if the linearity error of the recording head is Er, the difference between the track trajectories of the recording head and the reproducing head is E _s , and the track deviation of the reproducing head from the standard tape is E _p , then E _r = E _p + E _s and the magnetic tape The linearity of the recording head for recording should be such that the track deviation of the reproducing head from the standard tape and the difference between the track trajectories of the recording head and the reproducing head overlap. That is, the error is the sum of the adjustment error and the error of the track loci of the reproducing head and the recording head, and in a so-called narrow track magnetic recording / reproducing apparatus having a narrow recording track, the track locus error of the recording head and the reproducing head cannot be ignored. Since the compatibility adjustment is performed by the reproducing head, the recording track on the magnetic tape recorded by the recording head for actual recording is different, and it is difficult to guarantee the linearity compatibility of the magnetic recording / reproducing apparatus or the magnetic recording / reproducing apparatus is used for recording. It is difficult to guarantee magnetic tape compatibility. Further, there is a problem that a part of a necessary track is erased or left unerased at a connecting portion during editing.

The present invention solves the above-mentioned conventional problems, and when performing mechanical compatibility adjustment of a magnetic recording / reproducing apparatus with a reproducing head, a track locus error between the recording head and the reproducing head becomes irrelevant, and the magnetic tape is truly It is an object of the present invention to provide an adjusting device for a magnetic recording / reproducing apparatus, which can guarantee linearity for recording and can perform an adjustment that enables the use of a narrow track magnetic recording / reproducing apparatus.

Means for Solving the Problem In order to solve this problem, an adjusting device of a magnetic recording / reproducing apparatus of the present invention reproduces a track deviation of a reproducing head from a standard recording medium which is a mechanical compatibility standard of a head drum device. Error detection means for detecting from the reproduction signal of the head,
Error detection storage means for detecting and storing a track locus error on the magnetic tape between the recording head and the reproduction head, and the recording head by calculating the error stored in the error detection storage means and the error detected by the error detection means. And a calculating means for obtaining the track deviation of.

Operation With the above-described configuration, the magnetic recording / reproducing is performed by calculating the track deviation when the standard recording medium is reproduced by the reproducing head and the track locus error between the storage head and the reproducing head stored in the error detecting and storing means by the calculating means. The absolute value of the track deviation from the mechanically compatible reference format of the recording head locus of the apparatus is obtained.

Embodiments An embodiment of the present invention will be described below with reference to the drawings with respect to a magnetic recording / reproducing apparatus using a 2CH division recording system.

FIG. 1 is a block diagram of an adjusting device according to an embodiment of the present invention, which uses an azimuth time difference detecting circuit as linearity detecting means. In FIG. 1, a signal divided into 2CHs passing through a video signal processing circuit 31 is amplified by a recording head amplifier 32, and is magnetically transmitted through a pair of recording-only pair heads 10, 11 or 5, 6 having different azimuth directions. Record on tape 14. The recorded signals are a pair of read-only pair heads 8, 9 or 3, 4 which form pairs with different azimuth directions.
Are reproduced by the reproducing head amplifier 33 and amplified through the reproducing head amplifier 33, and the sync signals (Hsync (A), Hsync (B)) are separated by the video signal processing circuit 34, respectively, and reproduced from the pair heads 8, 9 or 3, 4 respectively. The azimuth time difference detection circuit 35 detects the relative time lag between the Hsync (A) and Hsync (B) of the synchronization signal of, and the DA converter 36 converts the time lag into an amplitude lag, and an arithmetic circuit including a differential amplifier Input to one input terminal of 37.
Also, the relative time lag of this synchronizing signal is stored in the RAM 39 through the switch 38, and the DA converter 40 is used during standard tape playback.
(The time shift is converted into an amplitude shift and input to the other input terminal of the arithmetic circuit 37.

The operation will be described with reference to FIG. First, the deviation of the relative traveling locus between the recording head and the reproducing head is detected. Therefore, a dedicated pair head for recording signals on magnetic recording tape
It is recorded by 10, 11 or 5, 6 and the signal is read by the read-only pair heads 8, 9 or 3, 4 in the state of simultaneous reproduction or self recording / reproduction. The read signal is separated by the video signal processing circuit 34, and the sync signal (Hsync (A), Hsync
After (B)) is taken out, the azimuth time difference detection circuit 35 detects the time difference between the paired heads of the taken out sync signal and stores it in the RAM 39 serving as storage means. At this time, the switch 38 is ON and the azimuth time difference detection circuit 35 and RA
It is connected to M39.

Next, a standard tape, which is the standard of linearity, is run, the reproduction signal of the read-only pair head 8, 9 or 3, 4 is amplified, and the sync signal (Hsync
(A), Hsync (B)) are taken out, and after the time difference is detected by the azimuth time difference detection circuit 35, DA conversion is performed by the DA converter 36 and the result is input to the arithmetic circuit 37. On the other hand, the track locus deviation between the recording head and the reproducing head, which is previously detected and stored in the RAM 39, is DA-converted by the DA converter 40 and is input to the arithmetic circuit 37. The arithmetic circuit 37 adds these two kinds of shift signals to obtain information on the track shift from the standard tape of the recording head. At this time, the switch 38 is in the OFF state.

FIG. 2 shows the process of calculating the error based on the error curve obtained by the azimuth time difference detection circuit. In FIG. 2, 41 is an oscilloscope screen.
Reference numeral 42 is a track locus error curve of the loci of the recording head and the reproducing head, where the horizontal axis represents time and the vertical axis represents the relative deviation amount. 43
Is the track deviation curve of the playback head during standard tape running,
Reference numeral 44 is a track deviation curve of the recording head showing the calculation results of the track locus error curve 42 and the track deviation curve 43. In this way, the track locus error curve 42 of the self-recording reproduction of FIG. 2 (a) is stored in the RAM 39 of FIG. 1, and then the compatibility confirmation standard tape is reproduced, and the track deviation of the reproducing head from the standard tape is caused. A curve 43 is obtained from the azimuth time difference detection circuit 35, and the track deviation curve 43 of the reproducing head and the track locus error curve 42 of the RAM 39 are superposed and calculated to obtain a track deviation curve 44 of the recording head of FIG. 2C. .

In this embodiment, the synchronization signal is used to detect the azimuth time difference, but it goes without saying that it may be any signal as long as the time difference between the pair heads can be measured relatively.

As described above, according to the present embodiment, the true track deviation recorded on the magnetic tape can be easily detected by calculating the track trajectory error between the reproducing head and the recording head.

As described above, according to the adjusting device of the magnetic recording / reproducing apparatus of the present invention, in order to guarantee the mechanical compatibility of the magnetic recording / reproducing apparatus, it becomes a standard for the mechanical compatibility of the recording head for true recording. Track deviations can be obtained, and more accurate adjustments can be made. The practical effect is extremely large in the future trend of narrowing tracks.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of an adjusting device of a magnetic recording / reproducing apparatus of the present invention, FIGS. 2 (a) to 2 (c) are explanatory diagrams of a linearity calculation process, and FIG. 3 is a head of a head drum device. FIG. 4 is a block diagram showing an envelope detecting device in a conventional example, FIG. 5 is a block diagram of an adjusting device in another conventional example using an azimuth time difference, and FIG. 6 is an envelope detecting device. FIG. 7 is a waveform diagram showing an example, FIG. 7 is a waveform diagram showing an example of azimuth time difference linearity detection, and FIG. 8 is a bitter diagram showing a track locus difference between the recording head and the reproducing head. 3,4 and 8,9 …… Pair heads for playback only, 5,6 and 10,11
...... Recording pair head, 31,34 …… Video signal processing circuit, 32 …… Recording head amplifier, 33 …… Playing head amplifier, 35 …… Azimuth time difference detection circuit, 36,40 …… DA converter, 37 …… Arithmetic circuit, 38 …… switch, 39 …… RAM, 41
…… Oscilloscope screen, 42 …… Relative displacement curve between recording head and reproducing head, 43 …… Reproducing head linearity in standard tape reproduction, 44 …… Recording head linearity.

Claims (1)

(57) [Claims] 1. A head drum device having at least a recording head for recording a signal on a magnetic recording medium and a reproducing head for reading a signal recorded on the recording medium, and a standard serving as a mechanical compatibility standard for the head drum device. Error detecting means for detecting a track deviation of the reproducing head from the recording medium from a reproduction signal of the reproducing head, and error detecting and storing means for detecting and storing a track locus error on the magnetic recording medium between the recording head and the reproducing head. And an operation unit for calculating the error detected by the error detection unit and the error stored in the error detection storage unit to obtain the track deviation of the recording head. .