JPH0573812A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To enable recording of data to a magnetic tape and monitor operation after the recording by using a rotary head device with two heads. CONSTITUTION:The rotary head device equipped with two magnetic heads for serving both recording and reproducing is used. Data is recorded on a magnetic tape T under the first scanning A (1) out of scanning the magnetic tape two times by one magnetic head while a rotary drum is rotated two times, and the recorded data is reproduced by the next, second scanning A (2). However, during this time, the other magnetic head is not participant of the recording or reproducing operation. Then, when the rotary drum is rotated two times after one track (a) is recorded and reproduced by scanning two times as mentioned above, data is recorded in a track (b) following the above track (a) by scanning B (1) of the other magnetic head, and then the recorded data is reproduced by the second scanning B (2) of the same magnetic head.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary head type magnetic recording / reproducing apparatus, and more particularly, it continuously records and reproduces magnetic data by using a rotary head apparatus having a pair of magnetic heads. The present invention relates to a magnetic recording / reproducing device capable of immediately monitoring recorded data.

[0002]

2. Description of the Related Art When recording data requiring reliability such as computer data by a magnetic recording / reproducing apparatus using a rotary head device, the recorded data is immediately reproduced to perform an error check. The read-after-write operation is performed. As a conventional magnetic recording / reproducing apparatus for performing a read-after-write operation, a 4-head type rotary head device 1 as shown in FIG. 7 is used. This rotary head device 1 has its rotary drum 1a.
A recording head A1 for recording data at a predetermined azimuth angle, a reproducing head A2 for reproducing data at the azimuth angle, a recording head B1 for recording data at a different azimuth angle, and the recording data thereof. There are provided four magnetic heads, ie, a reproducing head B2 for reproducing information. The magnetic tape T is wound around the rotary head device 1 and runs.

The diameter of the rotary drum 1a is 30 mm, the rotation speed n is 2000 rpm, the winding angle of the magnetic tape T with respect to the rotary drum 1a is 90 degrees, and the running speed V of the magnetic tape T is 8.15 mm / sec. In this case, as shown in FIG. 8, data is recorded on a track having a width of 13.6 μm.

FIG. 8 shows scanning of the magnetic head in the apparatus of FIG. 7 from the recording surface side of the magnetic tape T. The magnetic tape T is helically wound around the rotary head device 1, and each of the magnetic heads A1 to B2 obliquely scans the recording surface of the magnetic tape T. At this time, first, the recording head A1 performs recording on the track (a), and the recording head B1 performs recording on the adjacent track (b). Next, the reproducing head A2 reproduces the recorded content of the already recorded track (a), and the reproducing head B2 reproduces the recorded content of the already recorded track (b). The data reproduced by the reproducing head A2 and the reproducing head B2 are subjected to an error check by the check processing section, and the data recorded on the tracks (a) and (b) are proper data based on the error correction rate. It is determined whether there is any.

[0005]

As shown in FIGS. 7 and 8, in order to perform a read-after-write operation in which data is recorded on a magnetic tape and the recorded data is immediately reproduced, a rotary drum has been used. Since the la head 1a includes a total of four heads including a pair of recording heads and a pair of reproducing heads, the rotary head device 1 has a complicated structure and is expensive.

The present invention solves the above-mentioned conventional problems, and a magnetic recording / reproducing apparatus capable of recording / reproducing data on / from a magnetic tape by using a rotary head device having a minimum number of magnetic heads. Is intended to provide.

[0007]

A magnetic recording / reproducing apparatus according to the present invention comprises a rotary head device having a pair of magnetic heads having magnetic gaps having different azimuth angles, and a magnetic tape wound around the rotary head device. A tape running mechanism for running the magnetic tape, the recording operation is performed in the first scan when the one magnetic head scans the magnetic tape twice, and the data recorded by the second scan is reproduced. After reproduction, data is recorded following the track recorded by the one magnetic head in the first scan when the other magnetic head scans the magnetic tape twice, and is recorded by the second scan of the same magnetic head. It is characterized in that the reproduced data is reproduced.

[0008]

According to the above means, the rotary head device equipped with two magnetic heads for both recording and reproduction enables recording and reproduction of data on the magnetic tape, that is, a read-after-write operation. That is, data is recorded on the magnetic tape in the first scan in which the rotating drum rotates twice and one of the magnetic heads scans the magnetic tape twice, and the data recorded by the second scan is reproduced. .. During this period, the other magnetic head does not record or reproduce. After one track is recorded and reproduced by the two scans, when the rotating drum rotates twice, the other magnetic head records data on the track following the recording track, and the same magnetic head The data recorded by the second scan is reproduced.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.
1 to 3 show a first embodiment of a magnetic recording / reproducing apparatus according to the present invention. FIG. 1 is a plan view showing a rotary head device and a running system of a magnetic tape, and FIG. 2 is a rotary drum and windings around the rotary drum. FIG. 3 is a front view showing a magnetic tape that is run while being held.
FIG. 4 is an explanatory diagram showing recording tracks of data on a magnetic tape. The rotary head device 10 shown in FIGS. 1 and 2 includes a fixed drum 10b, a rotary drum 10a that rotates coaxially with the fixed drum 10b, and a motor that drives the rotary drum 10a.

In the rotary drum 10a, two magnetic heads A and B are provided at an arrangement angle of 180 degrees. The magnetic heads A and B are both recording / reproducing heads and have magnetic gaps with different azimuth angles. As shown in FIG. 2, both magnetic heads A and B are arranged side by side in the rotating direction of the rotary drum 10a.
And B are mutually set with a deviation amount in the direction of the rotation axis O-O. In this embodiment, the magnetic head B is displaced from the magnetic head A by 3.4 μm (¼ of the track 13.6 μm to be recorded) toward the upper end side of the rotary drum.
The gap width (width of the magnetic gap with respect to the scanning direction of the magnetic tape) W between the magnetic heads A and B is the width dimension (1) of the track to be recorded (for example, (a) shown in FIG. 3).
The size is sufficiently larger than 3.6 μm).

The magnetic tape T has a loading post 11
And 12 are wound around the rotary head device 10 at an angle of about 90 degrees, sandwiched between the capstan 13 and the pinch roller 14, and travel at a speed V according to the rotation speed of the capstan 13. The recording processing unit 15 and the reproduction processing unit 16 and the magnetic heads A and B are connected by a switch S.
It is switched by W1 and SW2. Fixed drum 1
Signals are exchanged between 0b and the rotary drum 10a by a rotary transformer.

Next, the operation of the magnetic recording / reproducing apparatus according to the first embodiment will be described. Here, the rotary drum 10a
Diameter is 30 mm, and the winding angle of the magnetic tape T is 90
And the running speed V of the magnetic tape T is 8.15 mm / sec.
(All are the same as the conventional example of FIG. 7). However, the rotation speed n of the rotary drum 10a is 8000 rpm, which is four times that of the conventional example shown in FIG. Under this condition, as shown in FIG. 3, the magnetic tape T has a track width Wt of 13.6 μm.
The data is recorded at, and compatibility with the device shown in FIG. 7 can be obtained.

FIG. 3 shows the recording and reproducing states of data on the recording surface of the magnetic tape T in this case.
This drawing shows the recording surface of the magnetic tape from the rotary drum 10a side (direction III in FIG. 1). Every time the rotary drum 10a rotating at 8000 rpm makes two revolutions, the switch SW2 is switched to the a2 or b2 side. Then, with the switch a2 or b2 being switched to, the switch SW is turned every rotation of the rotary drum 10a.
1 is alternately switched to the r and p sides. In FIG. 3, the scanning locus of the magnetic head A in the first rotation when the switch SW2 is switched to the side a2 is indicated by A (1), and the scanning locus of the magnetic head A scanned in the second time is A (2). Indicate. Similarly, the scanning locus of the magnetic head B that scans the magnetic tape T at the first rotation when the switch SW2 is switched to the b2 side is indicated by B (1), and 2 of the same magnetic head B is shown.
The scanning locus of the rotation is shown by B (2).

While the switch SW2 is still switched to the a2 side, the rotary drum 10a makes two revolutions, but in the first rotation at this time, the switch SW1 is switched to the r side and the locus A ( By 1), the track shown in FIG. 3A is recorded. The recording area width of the (a) track recorded at this time is Wr, which is the same as the width dimension W of the magnetic head A, which is sufficiently wider than the original track width (13.6 μm). At the next second rotation, the switch SW1 is switched to the p side, and at the second rotation, the magnetic head A enters the reproduction mode.

Comparing this first embodiment with the conventional example shown in FIGS. 7 and 8, the running speed V of the magnetic tape T is the same, and in this embodiment, the rotation speed of the rotary drum 10a is four times. is there. Therefore, the interval in the track width direction when the same magnetic head scans the magnetic tape T is (13.6) in FIG.
X2) μm, whereas in this embodiment, the loci A (1) and A when the same A head scans the magnetic tape T
The distance from (2) in the track width direction is (13.6 / 2 =
6.8) μm. That is, the switch SW1 is a2
After the magnetic head A records the track (a) in the recording mode by the first one rotation in the state of being switched to the side,
At the second rotation, the same magnetic head A depending on the reproduction mode was 6.
The magnetic tape T is scanned along the locus A (2) which is displaced by 8 μm. Therefore, at this time, the width Wp with which the magnetic head A scans the recording area of the track (a) is (Wr−6.8) μm.
Is. With the magnetic gap for this overlap, the data recorded on the track (a) is reproduced by the magnetic head A, and the reproduction processing unit 16 performs an error check.
The data recorded on the track (a) is monitored and checked.

Immediately after the magnetic head A scans the magnetic tape T along the locus of A (2), the switch SW2 is switched to the b2 side, and thereafter, the magnetic head B scans the magnetic tape T twice. Only B works. Then, in the first scanning locus B (1) of the magnetic head B, the switch SW1
Is switched to the r side, and the next track (b) is recorded by the magnetic head B. Magnetic head A and magnetic head B are 1
Since the arrangement angle is 80 degrees, the scanning locus B (1) of the magnetic head B is set by setting the deviation amount between the magnetic heads A and B in the rotation axis OO direction to the value shown in FIG. Scanning is performed with a space of 13.6 μm in the track width direction with respect to the track (a). That is, track (a) is 1
Overwriting is performed by the magnetic head B while leaving a width dimension of 3.6 μm, and a recording track with a track width Wt = 13.6 μm remains. In the next rotation, the switch SW2 remains on the b2 side and the switch SW1 is switched to the p side, and the same magnetic head B in the reproduction mode is moved to track (b).
Scan the magnetic tape with a deviation of 8 μm (scan locus B
(2)) The data of the track (b) is reproduced by the magnetic gap of the magnetic head B in the area overlapping the track (b), and the data recorded on the track (b) is monitored and checked.

The above operation, that is, each time the heads A and B scan the magnetic tape T twice by the rotation of the rotary drum 10a, the switch SW2 is switched, and in the middle thereof, each time the magnetic head A or B scans once. By switching the switch SW1 on the magnetic tape T, a recording track having a width of 13.6 μm is formed on the magnetic tape T. Comparing FIG. 7 with this embodiment, since the number of rotations of the rotary drum 10a is four times in this embodiment, the clock frequency for recording by the magnetic head A or B is the same as that of the conventional example of FIG. By quadrupling, the data recorded by this embodiment and the data recorded by the conventional example of FIG. 7 become compatible.

Further, in the embodiment shown in FIGS. 1 to 3,
The rotation speed of the rotary drum 10a is set to 4000 rpm (1/2 of that in the above embodiment), and the running speed of the magnetic tape T is set to (8.1
Even if it is 5/2) mm / sec, recording and reproduction can be performed on the same track as in FIG.

Next, FIGS. 4 to 6 show a second embodiment of the present invention. FIG. 4 is a front view of the rotary drum in the second embodiment, FIG. 5 is an explanatory view showing a scanning state of the magnetic head viewed from the recording surface side of the magnetic tape, and FIG. 6 is an explanatory view of scanning timing of the magnetic head. The rotary drum 10a of the rotary head device 10 in this embodiment has the recording / reproducing heads A and B (A and B having different azimuth angles) with an arrangement interval of 180 degrees as in the embodiment shown in FIGS. Has a magnetic gap). However, in this embodiment, as shown in FIG. 4, the magnetic heads A and B arranged in the rotation direction of the rotary drum 10a have different heights in the rotation axis OO direction, and the magnetic head B is higher than the magnetic head A. Is also arranged at a position displaced by 6.8 μm in the direction of the fixed drum 10b.

Further, in the second embodiment, the rotary drum 10
The diameter of a is 30 mm, and the running speed V of the magnetic tape T is 8.
At 15 mm / sec, both are the same as in the first embodiment, but the rotation speed of the rotary drum 10a is 4000 rpm,
It is 1/2 of the first embodiment, which is twice that of the conventional example shown in FIG.
The switching operation for each magnetic head A is the same as that of the first embodiment of FIG. 1, and the switch SW2 is alternately switched to the a2 side and the b2 side by every two rotations of the rotating drum 10a, and further one rotation of the rotating drum 10a. Switch S for each
W1 is switched to the r side and the p side.

Next, the operation of the second embodiment will be described. In FIGS. 5 and 6, the switch SW2 shown in FIG.
The scanning locus of the magnetic head A in the first rotation when switched to the side is indicated by A (1), and the scanning locus of the magnetic head A scanned in the second time is indicated by A (2). Similarly, the scanning locus of the magnetic head B that scans the magnetic tape T at the first rotation while the switch SW2 is switched to the b2 side is B
The scanning locus for the second rotation is indicated by (1) and is indicated by B (2).

In the first rotation in which the switch SW2 shown in FIG. 1 is switched to the side a2, the switch SW1 is switched to the side r, and the magnetic head A is in the recording mode. A track (a) having a width of Wr is recorded on the magnetic tape T running at the speed V by the scanning locus A (1) of the first rotation of the magnetic head A. In the second rotation with the switch SW2 switched to the a2 side, the switch SW1 is switched to the p side and the magnetic head A enters the reproduction mode. Since the traveling speed V of the magnetic tape T is the same as that of the conventional example of FIG. 7 and the number of rotations of the rotary drum 10a is twice that of the conventional example of FIG. 7, the same magnetic head A scans the magnetic tape T on a locus A ( The width of 1) and A (2) in the track direction is 13.6 μ, which is half that of the conventional example in FIG.
m. Since the gap width dimension W of the magnetic heads A (and B) is sufficiently larger than the track width dimension of 13.6 μm, a part of the track (a) is traced by the magnetic gap of the magnetic head A traveling on the trajectory A (2). The magnetic head A scans with Wp = (Wr-13.
6) The already recorded track (a) is scanned with a width of μm, the recorded data on the track (a) is reproduced, and the recorded data is monitored and checked.

Next, after the magnetic head A finishes scanning the locus A (1), the switch SW2 shown in FIG. 1 is switched to the b2 side, which continues while the magnetic head B scans the magnetic tape T twice. It The switch S2 is switched to the switch b2 when the first magnetic head B is scanned.
W1 is switched to the r side, and the magnetic head B enters the recording mode. The scanning locus B (1) of the magnetic head B is
The position is spaced from the scanning locus A (1) of the magnetic head A by 13.6 μm in the track width direction, that is, the same position as the scanning locus A (2) of the magnetic head A in the reproduction mode.

That is, the rotary drum 10a is 4000 rp
When rotating at m, the same magnetic head A is
The magnetic tape is scanned at intervals of 13.6 μm for each 360 ° rotation of 0a. At this time, if there is no deviation between the magnetic head A and the magnetic head B in the rotation axis OO direction,
The magnetic head B, which is arranged at an angle of 180 degrees with respect to the magnetic head A, passes a locus in the middle of the scanning locus of the magnetic head A. Therefore, in the second embodiment, as shown in FIG. 4, the magnetic head B is displaced toward the fixed drum along the axis OO by a dimension of 1/2 of 13.6 μm, whereby the magnetic head in the recording mode is set. The scanning locus B (1) of B coincides with the scanning locus A (2) of the magnetic head A in the reproduction mode. Overwriting is performed by the magnetic head B at the portion overlapping the track (a) by the locus B (1). Then, when the magnetic head B scans the magnetic tape next time, the switch SW1 is switched to the p side to change the magnetic head B
Is set to the reproduction mode, and the track (b) is set to the scanning locus B (2).
At this point, the magnetic head scans, and the recorded contents of track (b) are monitored and checked.

As described above, in the second embodiment, the number of rotations of the rotary drum 10a is twice that of the conventional example, and is 1/1 of that of the first embodiment.
2, recording was performed with a track width of 13.6 μm,
In addition, the recorded data can be monitored and checked. If the clock frequency of the recording data is doubled as compared with the conventional example shown in FIG. 7, compatibility is maintained between the tapes recorded by the respective devices of the conventional example shown in FIG. 7 and the first embodiment shown in FIG. Will be able to.

[0026]

As described above, according to the present invention, it becomes possible to record and monitor data by using a two-head rotary head device. Therefore, it becomes possible to improve the reliability of data recording for a computer or to manufacture a DAT device or the like that immediately reproduces recorded music information at a low price.

[Brief description of drawings]

FIG. 1 is a structural diagram showing a rotary head device of a magnetic recording / reproducing apparatus and a traveling path of a magnetic tape according to a first embodiment of the present invention,

FIG. 2 is a front view showing a scanning state of the magnetic head with respect to the magnetic tape in the first embodiment;

FIG. 3 is an explanatory view showing the scanning state of the magnetic head with respect to the magnetic tape in the first embodiment, as viewed from the recording surface side of the magnetic tape;

FIG. 4 is a front view showing a scanning state of a magnetic head on a magnetic tape of a magnetic recording / reproducing apparatus according to a second embodiment of the present invention;

FIG. 5 is an explanatory view showing a scanning state of the magnetic head with respect to the magnetic tape in the second embodiment;

FIG. 6 is an explanatory diagram showing the timing at which each magnetic head scans a magnetic tape in the second embodiment;

FIG. 7 is a plan view showing a rotary head device of a conventional 4-head type magnetic recording / reproducing apparatus and a scanning state of a magnetic tape;

FIG. 8 is an explanatory view showing a scanning state of a magnetic tape by a conventional four head from the recording surface side of the magnetic tape,

[Explanation of symbols]

 A, B magnetic head T magnetic tape 10 rotary head device 10a rotary drum

Claims (1)

[Claims] 1. A rotary head device comprising a pair of magnetic heads having magnetic gaps of different azimuth angles,
A tape running mechanism for running the magnetic tape wound around the rotary head device is provided, and the recording operation is performed by the second scanning in the first scanning when the one magnetic head scans the magnetic tape twice. Data is reproduced, and after the reproduction of the data, the data is recorded following the track recorded by the one magnetic head in the first scan when the other magnetic head scans the magnetic tape twice. A magnetic recording / reproducing apparatus characterized in that the recorded data is reproduced by the second scanning of the same magnetic head.