JPH0714141A - Band-shaped magnetic recording medium and magnetic head and magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To decrease such phenomena that the signals from plural channels simultaneously generate errors by setting the joined part to a leader tape and both ends of the traveling direction of a splicing tape at a prescribed angle to a traveling direction. CONSTITUTION:The joined part of the band-shaped recording medium 1 and the leader tape 2 and both ends in the traveling direction of the splicing tape 3 for splicing the joint part are set at 45 to 85 deg. or 95 to 135 deg. angle to the traveling direction of the band-shaped recording medium 1. As a result, the diagonal mapping shapes with the traveling direction are eventually generated at the beginning and terminal ends of the band-shaped medium, unlike the shape change by the prior technique. Then, a time leg is generated between the channels and the possibility of simultaneous increasing of the error rates with the plural channels is drastically lessened at the time of passing of the shape changing parts over the gap of the head even if a conventional recording and reproducing apparatus is used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a strip-shaped magnetic recording medium, a magnetic head and a magnetic recording / reproducing apparatus according to a magnetic recording / reproducing system which is widely used as a storage medium for video, audio and information equipment.

Specifically, in simultaneous recording / reproducing on a plurality of channels by a fixed head, a strip-shaped magnetic recording medium having extremely high signal reliability, in which signals are not attenuated or lost simultaneously on all channels, a magnetic head, and magnetic recording / reproducing. It supplies equipment.

[0003]

2. Description of the Related Art A recording / reproducing apparatus using a band-shaped magnetic recording medium is widely used in the fields of video and audio, and its recording / reproducing system is adopted in a fixed head system and a VTR which are adopted in an audio tape recorder. There are two types of helical scan methods.

In the video field and the audio field, which are the main applications of these applications, the recording format is rapidly changing from an analog signal to a digital signal in order to improve the signal quality.
Especially for the helical scan method, audio equipment such as 8 mm VTR format and DAT format, and D-
Many digital signal recording / reproducing devices such as video devices in the 2 format and the D-3 format have been made.

On the other hand, in the fixed head system, the increase in the amount of signal when digitizing the original analog signal and the technical support for the recording / reproducing technology have been delayed, but the digital signal compression technology and the multi-channel of the thin film magnetic head have been delayed. As a result, it was realized in 1992 as a recording / playback device in the DCC (Digital Compact Cassette) format.

[0006]

In the DCC format, 2ch (Lch / Rch) audio analog signals are digitized and compressed, and are allocated to a plurality of channels arranged in parallel in the tape longitudinal direction. .

At this time, a magnetic signal is simultaneously recorded and reproduced on a plurality of channels by a multi-channel thin film magnetic head installed so that the head gap surface is at a direction of 90 degrees with respect to the tape running direction.

On the other hand, the strip-shaped magnetic recording medium is generally wound around a cylindrical hub or reel via a leader tape. Therefore, in the vicinity of the start end and the end of the medium, the shape of the splicing tape used for joining the leader tape in the width direction of the tape and the shape of the clamper joining the leader tape to the hub or reel is reflected, It is usual that the medium itself undergoes uniform shape changes in the width direction.

That is, inevitably, the ridge of the undulation that accompanies the image is deformed so that it runs in the width direction.

Among them, especially regarding the image of the splicing tape and the splicing tape, it is impossible to physically eliminate the change in thickness, so that the change in shape always occurs.

As a mechanism for driving the belt-shaped medium, a method is generally used in which a tape is sandwiched between a pinch roller and a capstan and the driving force of the capstan is transmitted to the medium. Indentations, stains, and the like generated tend to be easily aligned in the medium width direction.

When such a deformed portion or adhesion of a foreign substance passes over the magnetic head, contact with the head gap becomes temporarily unstable, and a considerable signal loss occurs.

In the helical scan method, since the deformed portion is diagonally crossed, only a part of the analog signal which is digitally divided is lost, and the correction circuit can sufficiently maintain the signal quality.

On the other hand, in the conventional fixed head system as seen in DCC or the like, the head gap surface is aligned in the width direction of the strip medium.

Therefore, the deformation and irregularity of the tape provided due to the above-mentioned cause are in the same direction as that of the tape. Therefore, there is a high probability that the signal strengths of a plurality of channels simultaneously decrease as the deformation passes.

Further, in the fixed head system, unlike the helical scan system, the head and the medium surface are brought into contact with each other by sliding at a low speed, so that a stick-slip phenomenon is likely to occur, and head striking or tape vibration accompanying traveling causes a plurality of channels. At the same time, the error rate tends to increase.

Further, slips in tape running due to dirt on the drive system and subtle jitter components for constant speed running cause a delay in data output timing, which also leads to an increase in simultaneous errors of a plurality of channels. .

On the other hand, the current signal processing technology has a structure that is vulnerable to an error that occurs over a plurality of tracks when an analog signal is converted into a digital signal and the signals are equally allocated to each track.

Take the DCC format as an example. First, the signal structure in the DCC format will be briefly introduced below. Audio signal (L-ch and R-c
h) One frame is a signal group in which an analog waveform equivalent to 0.17 sec is digitally converted and distributed and delayed equivalently to 8 tracks.

One frame is subdivided into 32 blocks per track. One block consists of a 510-bit signal divided into two signal areas called HEADER and BODY. The BODY is a 48-byte digital signal of modulated symbols, and the HEADER is a 3-byte digital signal as BODY allocation information. Written.

The breakdown is that the first 10 bits are SYNC WOR
It is D, and a 3-bit frame address and 5-bit block address are recorded in this record twice. Based on the playback signal by SYNC WORD, the PLL circuit synchronizes inside the recording / playback device, and the BODY is decoded by the opened window. If the reproduced signal of the SYNC WORD causes a timing shift or a signal loss that exceeds the allowable range of the PLL circuit, synchronization cannot be obtained at all and the subsequent BODY cannot be decoded.

64 bits are provided between frames as an inter-frame gap (IFG).

With the above-mentioned structure, one frame is constituted by the information amount of 48 bytes × 32 blocks × 8Tr = 12288 bytes as direct information when the analog waveform is digitally converted.

In the DCC format, a critical frame is defined as an uncertain error area between an error area where the information thus constructed can be reliably corrected by a correction circuit or the like and an error area where the information cannot be absolutely corrected.

Looking at the details of the definition, it does not matter if all the signals of one track are lost over one frame. However, when an error occurs over two tracks, only signal loss of up to 500 bytes is allowed. Further, when it extends over 3 to 8 tracks, a total of up to 100 bytes per frame is allowed, and if it exceeds that, it is regarded as a critical frame.

As can be seen from the definition of the critical frame, it is very difficult to correct an error across multiple tracks in the DCC format.

With respect to such a feature of the signal processing system, since a magnetic signal is input and output by the fixed head method having the drawbacks described above, a critical frame easily occurs due to the following phenomenon. .

That is, if the tape passes through an irregular portion of the tape or the driving is disturbed when the SYNC WORD of a certain BLOCK is read, the information of one block is lost in each track all at once, and the critical frame of the critical frame is lost. It easily exceeds the 100 bytes guaranteed by definition.

As can be seen from the above example, particularly in the combination of the signal processing system for performing A / D conversion in a form close to the DCC format and the fixed head system, the simultaneous error rate increase in a plurality of channels is passed through the correction circuit. However, there is a problem that the configuration is such that signal loss that cannot be repaired easily occurs.

[0030]

According to the present invention, in order to solve the above-mentioned problems, a joining portion between a belt-shaped magnetic recording medium and a leader tape, and both end portions in the running direction of a splicing tape that joins the joining portions are provided at the belt-shaped magnetic recording medium. The angle is 45 degrees to 85 degrees or 95 degrees to 135 degrees with respect to the traveling direction.

Alternatively, in a recording / reproducing apparatus for simultaneously recording and reproducing digital signals with a fixed magnetic head on a plurality of recording channels arranged in parallel on a strip-shaped magnetic recording medium, a head gap surface for recording and reproduction of each channel is provided. Using fixed magnetic heads each provided on the same cross section, the head gap surface and the magnetic recording medium are arranged so that the traveling direction is at an angle of 45 to 85 degrees or 95 to 135 degrees. , Or a recording / reproducing apparatus for simultaneously recording and reproducing digital signals simultaneously with a fixed magnetic head on a plurality of recording channels arranged in parallel on a long magnetic recording medium, each head gap for recording and reproduction of each channel. Surface is 0.252 in the running direction of the magnetic recording medium between each channel.
0.1 mm to 1.5 excluding the integral multiple area of 96 mm ± 3%
It is characterized in that it is provided with a minimum interval of mm.

Further, in addition to a solution described later, a delay circuit corresponding to a time difference obtained by dividing the head gap interval of each channel by the running speed of the strip-shaped magnetic recording medium is provided in the recording and reproducing signal circuit of each channel. It is a feature.

[0033]

The present invention having the above-mentioned constitution can obtain the following actions.

The joint portion between the strip-shaped magnetic recording medium and the leader tape, and both ends of the splicing tape for fixing the joint portion in the traveling direction are 45 degrees to 85 degrees or 95 degrees to 135 degrees with respect to the traveling direction of the strip magnetic recording medium. With such an angle, unlike the conventional shape change, an imaged shape oblique to the traveling direction is generated at the start and end portions of the belt-shaped medium.

Therefore, even if a conventional recording / reproducing apparatus is used, a time difference occurs between channels when the shape-deformed portion passes over the gap of the head, and the possibility of simultaneous error rate increase in a plurality of channels is greatly increased. It will be reduced.

Here, in the combination with the recording / reproducing apparatus whose operation will be described below, the angle / direction of the head gap surface with respect to the widthwise direction of the strip-shaped magnetic recording medium and the angle provided at the above-mentioned joining portion / both ends of the splicing tape are different. It is important not to be in the same direction.

The reason why the end portions of the strip-shaped magnetic recording medium / leader tape and the splicing tape are set at 45 ° to 85 ° or 95 ° to 135 ° is as follows.

That is, if the angle is in the range of 90 ° ± 5 °,
This is because it is not possible to obtain a sufficient time difference for each channel when the shape deforming portion passes.

At angles exceeding the range of 90 ° ± 45 °,
This is because the sharp edge of the strip-shaped magnetic recording medium, the leader tape, and the splicing tape slides on the head, the pad, and the like that accompany running, causing severe deterioration.

Further, a multi-channel thin film head having a head gap surface similar to the conventional one provided on the same cross section is used, and the running direction of the head gap surface and the magnetic recording medium is 45 degrees to 85 degrees.
The following effects can be obtained with respect to the angle of 95 degrees to 135 degrees.

That is, even if the shape-deformed portions aligned in the width direction on the strip-shaped magnetic recording medium pass, the timing at which the deformed portions pass on the head gap is deviated for each channel.
It is possible to provide a time difference in the output loss accompanying this, and as a result, it is possible to easily avoid simultaneous increase of errors in a plurality of channels.

In particular, in the present invention, in addition to the image of the splicing tape or the joining portion of the band-shaped magnetic recording medium and the leader tape, the image of the clamper and the foreign matters and indentations from the drive system which may occur in the width direction of the band-shaped medium. Can also be effective.

The angle of the head gap surface is set to 45 degrees 85 degrees or 95 degrees to 135 degrees with respect to the channel direction for the following reason.

That is, if the angle is in the range of 90 ° ± 5 °,
This is because the gap surface spacing of each channel is too small to provide a sufficient time difference with respect to the unstable contact state that occurs when the shape deforming portion passes.

At angles exceeding the range of 90 ° ± 45 °,
This is because the azimuth loss with respect to the magnetization direction of the band-shaped magnetic recording medium becomes large, and it becomes difficult to keep the contact state between the head and the medium constant between the channels at the farthest ends.

It is effective that the angle is preferably in the range of 90 ° ± 10 ° to 30 °.

The head gap surface of each channel is 9 with respect to the running direction of the magnetic recording medium as in the conventional fixed head.
Even though it is 0 degree, the gap position between the channels is 0.25296 mm ± 3 in the running direction of the magnetic recording medium.
The following effects can be obtained with respect to the magnetic head and the recording / reproducing apparatus which are formed by shifting with a minimum interval of 0.1 mm to 1.5 mm excluding the area of integral multiple of%.

That is, when one of the magnetic signal groups arranged in the width direction of the strip-shaped magnetic recording medium passes over the head gap, only a gap corresponding to one channel can exist on the same surface.

Therefore, even if the shape-deformed portions aligned in the width direction on the strip-shaped magnetic recording medium pass, the output loss due to passage of the deformed portions causes a time difference between the channels,
It is possible to avoid that errors occur simultaneously on multiple channels.

Also in the present invention, in addition to the image of the splicing tape or the joining portion of the band-shaped magnetic recording medium and the leader tape, the image of the clamper and the foreign matters and indentations from the drive system which may be generated in the width direction of the band-shaped medium. Can also be effective.

Further, since the head gap surface is 90 degrees with respect to the running direction of the magnetic recording medium, recording / reproducing can be performed in the direction of magnetic anisotropy provided in the long magnetic recording medium, which is different from the conventional technique. The same recording / reproducing characteristics can be maintained.

Here, the minimum gap between the head gap surfaces between the channels is set to 0.1 mm to 1.5 mm, which is similar to the above reason in that the time difference effect can be effectively obtained and the recording / reproducing apparatus has the same effect. This is obtained from the upper limit of the realistic head size that can be obtained.

In the case of the existing DCC format, it is more advantageous to have a wide interval, preferably 1.02 mm to 1.5 mm.

The reason is that in the DCC format, the tape length corresponding to the interval for each frame is 8.126 mm, so by setting the interval generated in 8 tracks to be longer than that, all the tracks generated at a certain moment are covered. This is because the error is automatically divided into two frames.

Further, the reason why the minimum interval of the head gap is set to exclude the area of an integer multiple of 0.00496 mm ± 3% is that the cycle of the SYNC WORD signal corresponds to this interval especially in the DCC format. This is because setting the interval will coincide with the timing of reading the SYNC WORD signal of the adjacent BODY.

Further, using the fixed head with the gap position shifted, it corresponds to the time difference obtained by dividing the head gap interval of each channel with respect to the farthest channel in the running direction of the magnetic recording medium by the running speed of the strip-shaped magnetic recording medium. The following effects can be obtained by incorporating the delay circuit to be incorporated into the recording and reproducing signal circuit of each channel.

That is, the magnetic patterns of the respective channels in which the input signals are recorded on the medium are arranged in the width direction of the strip medium by the function of the delay circuit as in the conventional device, and the width direction of the strip medium recorded by the conventional device. The output signal when reading the magnetic signals lined up in line is obtained by the function of the delay circuit for each channel signal at the timing according to the signal conversion system of the conventional device.

As a result, the compatibility with the conventional equipment can be completely achieved in reading and writing signals.

Furthermore, the following effects are obtained when one of the magnetic signal groups arranged in the width direction of the strip-shaped medium passes over the head gap of a channel.

That is, even if the jitter component due to the running characteristics of the band-shaped medium becomes large and the signal acquisition timing is missed and it is recognized as an error, the magnetic signal of the other channel in the row passes over the head gap of the channel. There is a time difference in passing.

For example, in the DCC format, it operates as follows. Whether the head gap is less than 1.0 mm or more, for example, when SYNC WORD of a block with 0 tracks misses the reproduction timing due to a jitter component on tape running, other 1 to 7 tracks are near the gap. Do the same for the other blocks in SYNC W
The probability of failing to read the ORD is very low.

Therefore, an error of 48 bytes occurs for the entire 1 block in the 0 track in which the SYNC WORD is not read, but the error for the other 7 tracks results in the unreadable bits only, and the error is 100 in total. It can be kept below the bite.

Further, the head gap distance is 1.0 m.
In the case of m or more, one or more tracks out of 8 tracks are reading the adjacent frame signal, and it is possible to avoid concentration of errors in the same frame.

As a result, it is possible to avoid an increase in simultaneous errors in a plurality of channels, which is caused by a timing shift due to poor running characteristics.

By using these actions alone or in combination, it is possible to avoid the worst situation in terms of signal quality, such as the simultaneous error rate increase in a plurality of channels peculiar to the fixed head system, which cannot be avoided by the conventional technique. It is a thing.

[0066]

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

(Embodiment 1) (FIG. 1) shows a joining portion between a belt-shaped magnetic recording medium and a leader tape in a conventional DCC tape adopted as an embodiment. 1 is the end of the strip-shaped magnetic recording medium, 2 is the end of the leader tape, 3
Is a splicing tape.

As can be seen from FIG. 1, the angle of each end that needs to be cut is set to 60 degrees with respect to the running direction of the belt-shaped medium in this embodiment.

(Embodiment 2) (FIG. 2) shows the position of the head gap and the channel position on the tape of the multi-channel thin film magnetic head mounted on the recording / reproducing apparatus in one embodiment of the present invention. It is a model figure.

In this embodiment, the recording / reproducing format is D
According to the CC standard, only the head having the gap structure shown in (FIG. 2) was prepared, and the DCC tape recorder (DC-1 manufactured by Matsushita Electric Co., Ltd.) which is already commercially available.
Listed in 0).

In the head according to the prior art, the section where the gaps of the recording head and the reproducing head of each channel are arranged is 90 degrees with respect to the tape running direction, while in this embodiment, as shown in FIG. The width of the head is 90 ° + 20 ° and the channel width of the head is widened so that the width during recording is the same as that of the conventional head.

(Embodiment 3) (FIG. 3) shows the position of the head gap and the channel position on the tape of the multi-channel thin film magnetic head mounted in the recording / reproducing apparatus in one embodiment of the present invention. It is a model figure.

In producing the head shown in this figure,
The gap for each channel was formed individually. Specifically, the channel that does not form a gap is masked,
After the formation of the magnetic gap of the required channel was completed, the minimum gap was formed over the whole by the core material, and then the gap of the next channel was formed.

In this way, the heads having the gap surfaces of the respective channels spaced by 0.8 mm were arranged as shown in FIG.

(Fourth Embodiment) In the fourth embodiment, in addition to the above-described third embodiment, the signal input / output unit for each channel of the head is further subjected to the signal delay processing corresponding to the running difference between the channels. Incorporated circuit. This is done for compatibility with the prior art.
FIG. 4 is a chart showing a conventional example at the time of recording.
Shows an input original signal, (b) shows a head configuration, and (c) shows a magnetic signal pattern on the tape. (FIG. 5) is a chart showing an embodiment of the present invention at the time of recording, (a) is an input signal after delay processing, (b) is a head configuration of Embodiment 4,
(C) shows a magnetic signal pattern on the tape. Also,
(FIG. 6) is a chart showing an embodiment of the present invention at the time of reproduction. (A) is a magnetic signal pattern on a tape, (b) is a head configuration of Embodiment 4, and (c) is a signal immediately after reading. ,
(D) shows the input signal after delay processing. The AUX notation is omitted in the figure.

Specifically, in the reproducing system, the difference in running time corresponding to the gap position of each channel is delayed to the output signal of that channel with reference to the channel farthest in the tape running direction, and in the recording system, reversely. The input signal is delayed by a running difference corresponding to the gap position of each channel with reference to the nearest channel.

As a result, between the furthest channels,
A correction of (6.4 mm / 47.6 mm) sec is added as a difference during driving.

(Comparative Example 1) (FIG. 7) shows the joining portion between the strip-shaped magnetic recording medium and the leader tape in the conventional DCC tape used as a comparative example. Reference numeral 1 is an end portion of the strip-shaped magnetic recording medium, 2 is an end portion of a leader tape, and 3 is a splicing tape.

As can be seen from FIG. 7, the angle of each end that needs to be cut is 90 degrees with respect to the running direction of the belt-shaped medium.

(Comparative Example 2) (FIG. 8) is a diagram showing the position of the head gap and the channel position on the tape in the conventional DCC format adopted as a comparative example.

As can be seen from FIG. 8, in the comparative example, the head gap surfaces of the respective channels are on the same cross section forming an angle of 90 degrees with the parallel channels.

The following measurements were carried out using the above Examples 1, 2, 3, 4 and Comparative Example. First, a trial tape having a thickness corresponding to 120 minutes of the DCC format was used to compare the number of critical frames in 10 minutes on the tape start and end sides.

Specifically, the DCC 120-minute tapes according to Example 1 and Comparative Example 1 were used in Examples 2, 3, 4 and Comparative Example 2.
I recorded it again on the DCC deck.

At this time, the beginning 5 minutes of the cassette A surface side and B
Philips DE for the last 5 minutes on the face side
MS (DCC ERROR MEASUREMENT
SYSTEM) was used to compare the number of critical frames per minute.

The results are shown in (Table 1).

[0086]

[Table 1]

As can be seen from these results, in the combination of the tape of Comparative Example 1 and the deck of Comparative Example 2, the number of critical frames was remarkably large in the two minutes on the A-side starting end side and the B-side ending side, and other sections were used. But many critical frames are being measured.

However, when Example 1 is used as a tape, the number of critical frames in the two minutes on the A-plane starting side and the B-side terminating side is significantly reduced.

In Comparative Example 1, 2 on the A surface starting end side and the B surface end side
The reason why the critical frames are concentrated in the minute is that the image of the splicing tape, the joint portion and the clamper has a great influence by using the thin 120 minute tape for the test.

On the other hand, the reason why the critical frame in this section is reduced in the first embodiment is that the time difference generated by making the cut ends of the respective joints have an angle with the gap arrangement on the head is effective. Therefore, the only critical frames counted are those due to the image of the clamper.

The critical frames in the other sections have poor reproducibility by repeated measurement and it can be determined that there is no difference between Example 1 and Comparative Example 1. Therefore, the critical frames are associated with the driving characteristics and the influence from the drive system. And so on.

In the decks of Examples 1 and 2, no critical frame was measured in 2 minutes on the A-side starting end side and the B-side ending side of both tapes of Example 1 and Comparative Example 1.

This is because the timing delay at the time of signal acquisition due to the gap position of the head being set at an angle with respect to the width direction of the strip-shaped medium or being shifted in the running direction is
It can be seen that not only the deformed portion of the tape due to the image of the splicing part or the clamper but also the image and foreign matters such as those generated in the drive system are effectively transferred.

The number of critical frames in the other sections is not so different from that in Comparative Example 2, but this is due to the influence of the delay of the timing of the output signal due to the jitter phenomenon and the like accompanying the running.

In Example 3, in the combination with the tape of Comparative Example 1, the number of critical frames was conspicuously high in 2 minutes on the A-side starting end side and the B-side end side, but in the combination with the tape of Example 1, this section The number of critical frames in is greatly reduced.

This indicates that it is not so effective as to the cause of the critical frame at the start and end portions.

The reason for this is that, in this deck, the magnetic signal of the same frame is written in the width direction on the tape as in the deck of Comparative Example 2 due to the function of the delay circuit.

However, in the other sections, the number of critical frames shows a very low level regardless of the first and comparative examples.

This result shows that by shifting the head gap position for picking up the magnetic signal between the channels, there is a delay in signal acquisition timing due to chatter between the tape and the head due to running characteristics, head hitting or jitter components during running. It shows that it works very effectively against the critical frame generated by the phenomenon described above.

Next, using the decks of Example 4 and Comparative Example 2, a practical sound skip test was performed using the tape of Example 1.

Specifically, as Comparative Example 1, an unmodified DCC tape recorder (DC-10) manufactured by Matsushita Electric Co., Ltd.
Using the prototype deck of Example 4 which was modified based on this, a 120-minute tape was input to each deck over the entire length and a single signal of 7 kHz was input to perform solid writing.

Then, skipping was measured over 100 hours and 200 hours during self-reproduction on each deck and during reproduction on the other deck.

The test environment at this time was 3 ° C. and 5% Rh, which is a low-temperature and low-humidity environment severe with respect to running characteristics.

To measure the sound skipping, input the audio signal output from each deck to a pen recorder (manufactured by National Instruments),
The number of times when the fluctuation (decrease) in the output level of the deck reached −2 dB was counted.

The results are shown in (Table 2).

[0106]

[Table 2]

In Table 2, the 120-minute tape is 6 for convenience.
It is divided into two areas, and the area and number of times when sound skipping is observed are tabulated and displayed for every 10 passes.

The number of sound skips is highest in the self-recording / reproduction of Comparative Example 2, occurs from the initial state, and tends to increase in the tape winding rather than in the start / end portions in accordance with the number of passes.

On the other hand, recording in Comparative Example 2 and Example 4
Although some of the data reproduced in step 1 occur from the beginning, the increase due to running 100 passes is small. There is reproducibility with respect to the sound skipping that has occurred from the beginning, and it occurs when recorded on the deck of the comparative example, and it is considered that the timing at the time of recording is shifted due to the influence of the running characteristics.

The data recorded by the deck of Example 4 and reproduced by the comparative example showed almost the same tendency as the self-recording / reproduction of the comparative example 2.

In contrast to the above results, in the self-recording and reproduction with the deck of Example 4, no skipping was observed throughout the test.

Although the effects of the DCC have been verified as the embodiments of the present invention, this does not limit the use of the present invention. For example, a data memory device or a device for digitizing and recording / reproducing a simple video signal. You may use as.

Further, the multi-channel head is not limited to the thin film magnetic head, but may be composed of a plurality of MIG heads or laminated heads which are widely known as VTR heads.

Regarding the way of shifting the head gap, the head gap may not be sequentially shifted for each channel No., but may be formed in a random pattern as long as the minimum distance between the channels is kept.

Further, as an application example of this, by making the position of the head gap surface for each channel a unique pattern according to the application, compatibility can be achieved only between devices having a gap layout of the same pattern. It is also possible to bring about the effects of proper use such as confidentiality protection when used as and a family of users.

[0116]

As is apparent from the above embodiments, according to the present invention, even if the shape-changing portion due to the image of the clamper and the splicing tape at the start and end portions peculiar to the long magnetic recording medium passes through, It is possible to avoid simultaneous occurrence of errors in a plurality of channels because the timing affected by the gap positions of the channels is different.

Particularly, in the strip-shaped magnetic recording medium according to the first aspect, it is possible to efficiently reduce the critical frame due to the image around the joint portion which occurs at the start and end portions of the strip-shaped medium.

Further, in the recording / reproducing apparatus and the magnetic head according to the second and third aspects, the image around the joint portion and the shape transfer of the clamper which are generated at the start and end portions of the band-shaped medium, and further, the indentation and the foreign matter adhesion due to the drive system are caused. The critical frame due to the influence can be efficiently reduced.

Further, in the recording / reproducing apparatus of the fourth aspect, a signal is caused by a temporary head touch lost caused by a subtle tape vibration or a head hit during traveling, or a jitter component on the traveling characteristic. A phenomenon such as a critical frame having no reproducibility that occurs due to a shift in the capture timing can be eliminated by providing a difference in the degree of influence between channels and the timing of the influence.

Further, the present invention can be judged to be very effective in that the compatibility with the conventional equipment can be completely maintained.

By independently or in combination of these inventions, it is possible to establish excellent recording / reproducing capability and signal reliability of a digital signal which is comparable to other systems, though it is a recording / reproducing device using a fixed type multi-channel magnetic head. Is possible.

[Brief description of drawings]

FIG. 1 is a peripheral view of a joint portion between a belt-shaped magnetic recording medium of Example 1 and a splicing tape.

FIG. 2 is a model diagram showing the relationship between the gap pattern of the magnetic head of Example 2 and each channel on the strip-shaped magnetic recording medium.

FIG. 3 is a model diagram showing the relationship between the gap pattern of the magnetic head of Example 3 and each channel on the strip-shaped magnetic recording medium.

FIG. 4 is a conventional recording chart (a) is an input original signal chart (b) is a head configuration chart (c) is a magnetic signal pattern chart on a tape

5A and 5B are a chart at the time of recording of Example 4, a chart of an input signal after a delay process, a chart of a head configuration, and a chart of a magnetic signal pattern on a tape.

FIG. 6 is a chart during reproduction of the fourth embodiment (a) is a chart of magnetic signal patterns on a tape (b) is a chart of head configuration (c) is a chart of signals immediately after reading (d) is a delay process Later input signal chart

FIG. 7 is a view of a peripheral portion of a joint portion between a belt-shaped recording medium of Comparative Example 1 and a splicing tape.

FIG. 8 is a model diagram showing the relationship between the gap pattern of the magnetic head of Comparative Example 2 and each channel on the strip-shaped magnetic recording medium.

[Explanation of symbols]

 1 band-shaped magnetic recording medium 2 leader tape 3 splicing tape

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takumi Haneda 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (5)

[Claims] 1. A joint portion with a leader tape and both end portions in the traveling direction of a splicing tape for connecting the joint portion are 45 ° to 85 ° or 95 ° to 1 with respect to the traveling direction.
A strip-shaped magnetic recording medium having an angle of 35 degrees. 2. A magnetic recording / reproducing apparatus for simultaneously recording and reproducing digital signals simultaneously on a plurality of recording channels arranged in parallel on a strip-shaped magnetic recording medium with a fixed magnetic head, wherein head gap surfaces for recording and reproducing of each channel. Using fixed magnetic heads each provided on the same cross section, the head gap surface and the magnetic recording medium are arranged so that the traveling direction is at an angle of 45 to 85 degrees or 95 to 135 degrees. And a magnetic recording and reproducing device. 3. A fixed magnetic head for simultaneously recording and reproducing a digital signal on a plurality of recording channels arranged in parallel on a strip-shaped magnetic recording medium, each recording and reproducing head gap surface of each channel being a magnetic recording medium. Has an angle of 90 degrees with respect to the running direction, and the head gap surface for recording and the reproducing head have a gap of 0.25296 mm ± 3% in the running direction of the magnetic recording medium between the channels, excluding an integral multiple area. A magnetic head provided with a minimum interval of 1 mm to 1.5 mm. 4. A magnetic recording / reproducing apparatus equipped with the magnetic head according to claim 3. 5. A delay circuit corresponding to a time difference obtained by dividing the head gap interval of each channel by the running speed of the strip-shaped magnetic recording medium is provided in the recording system and reproduction system signal circuits of each channel. The magnetic recording / reproducing apparatus described.