JPH0632175B2 - Magnetic head positioning device for magnetic disk recording / reproducing device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a magnetic head positioning device of a magnetic disk recording / reproducing device which is used by being connected to a computer such as a personal computer.

"Prior Art" In the conventional magnetic disk recording / reproducing apparatus, since the positioning of the magnetic head is performed by the open loop control, a highly accurate magnetic head feeding mechanism is required, which prevents cost reduction. Further, even some conventional magnetic disk recording / reproducing devices perform positioning of the magnetic head by feedback control. However, these have a special feedback circuit in the magnetic disk recording / reproducing device, so that the cost is low. I didn't.

"Problems to be Solved by the Invention" The present invention has been made in order to solve the above-mentioned problems, and a magnetic head feeding mechanism with low accuracy can read and write a magnetic disk without any inconvenience, and also has a special feedback circuit. It is an object of the present invention to provide a low-cost magnetic head positioning device that can control the positioning of a magnetic head without requiring it.

[Means for Solving Problems] According to the present invention, the step motor is rotated by the number of steps corresponding to the desired track position, and one step motor is provided on each side of the position. Detecting means for determining the number of sectors that can be read by the magnetic head at each of the positioning positions, and the distribution of the number of sectors determined by the detecting means are obtained for each of the positioning positions, and the average position of the distribution is determined. There is provided a magnetic head positioning device for a magnetic disk recording / reproducing device, comprising: a positioning means for positioning the magnetic head.

[Operation] According to the above configuration, in the magnetic disk recording / reproducing apparatus used by connecting to a computer such as a personal computer, first, the pulse motor is rotated by the number of steps corresponding to the desired track position, and then the detecting means. Since the distribution of the number of sectors that can be read by the magnetic head is obtained by the magnetic head and the magnetic head is positioned at the average position of the distribution by the positioning means, the magnetic head is always positioned at a position where the maximum number of sectors can be read. .

[Example] Next, an example of the present invention will be described with reference to the drawings.

As shown in FIG. 1 and FIG. 3, in the magnetic disk recording / reproducing apparatus 10, a feed screw 2 formed of synthetic resin is attached to the shaft of the step motor 1, and the feed screw 2 rotates. The movement is configured to move the feed table 4 in the axial direction of the support rod 6 via the feed spring 3,
Therefore, the single gap type magnetic head 5 mounted on the feed table 4 is positioned by the step motor 1. As shown in FIG. 5, the magnetic disk 20
It is essential that the step motor 1 and the feed screw 2 are designed so that the amount of movement of the magnetic head 5 for several pulses (two or more pulses) to the step motor 1 corresponds to the one track gap TG above. is there. In this embodiment, the step motor 1 and the feed screw 2 are designed so that the rotation of the step motor 1 for 4 pulses corresponds to the movement amount of the magnetic head 5 for one track.

As shown in FIG. 3, the magnetic disk recording / reproducing apparatus 1
In addition to the step motor 1 and the magnetic head 5, the magnetic disk drive circuit 11, the magnetic disk rotation motor 12, the magnetic disk control circuit 13 and the like are provided in the reference numeral 0. Then, the magnetic disk drive circuit 11
Is based on a command signal from the magnetic disk control circuit 13,
The stepping motor 1 and the magnetic disk rotating motor 12 are started and stopped, the rotation direction of the stepping motor 1 is switched, and the magnetic head 5 is operated for recording, reproducing and erasing. The magnetic disk control circuit 13 is connected to a computer 30 such as a personal computer. In addition, the magnetic disk control circuit 13
Is an area (not shown) for storing a control program for controlling the operation of the magnetic disk recording / reproducing apparatus 10 and areas 15, 16, 17, 1 for storing various data.
A memory 14 having 8, 19, 14a is connected. The control program stored in the memory 14 is
It is read by the computer 30, and the computer 30
By executing the control program, the computer 30 sends predetermined command information to the magnetic disk control circuit 1
3, the magnetic disk control circuit is transmitted to the computer 3
The magnetic disk drive circuit 11 is controlled based on the command information of 0, information is recorded on the magnetic disk 20 via the magnetic head 5, and unnecessary information recorded on the magnetic disk 20 is erased. The magnetic disk recording / reproducing device 10 is operated. In this example,
A computer 30 having another function such as a personal computer connected to the magnetic disk recording / reproducing apparatus 10 reads a control program for controlling the magnetic disk recording / reproducing apparatus 10 and directly issues a command to the magnetic disk control circuit 13. A computer is provided on the magnetic disk recording / reproducing apparatus 10 side, and a personal computer or the like connected to the computer is used as a host computer, and the computer on the magnetic disk recording / reproducing apparatus side is stored in a memory according to an instruction from the host computer. Of course, it may be configured to be operated according to the control program.

As shown in FIG. 5, the magnetic disk 20 is provided with a large number of concentric tracks 21, 22, 23, ... Of which, tracks 21, 23, 25 are arranged.
.. are write tracks, and tracks 22, 24 ... Are erase tracks. Each write track 21, 23, 25 ... Is divided into predetermined sectors 40 for recording information. In this embodiment, one track is divided into 9 sectors. The erasing tracks 22, 24 ... Are separation bands for preventing the information of the writing tracks 21, 23 from being mixed. Inside the sector 40, as shown in FIG. 4, there is an idea field 41 in which information indicating the start and address of the sector is recorded, and a data field 42 in which data is recorded. Before and after these,
A gap 43 is provided to protect data from rotation fluctuation, mechanical size error, erase gate delay timing error, and the like.

In the idea field 41, idea information having a predetermined number of bytes is written as a signal having two types of magnetization directions. When the magnetic head 5 is sent to the regular track position, the idea information of all the sectors on the track is read, but between the regular track position and the position of the magnetic head 5 sent by the step motor 1. Has an error, and it has been found by an experiment by the present inventor that the number of sectors 40 capable of reading the idea information gradually decreases as the error increases.

According to the present embodiment, it is possible to reduce the error between the track position written on the magnetic disk 20 and shown by the one-dot chain line 23c in FIG. 5 and the position of the magnetic head 5 sent by the step motor 1. This will be described as the next operation. The computer 30 reads the control program according to the flowchart shown in FIG. 6 from the memory 14 and transmits a command signal to the magnetic disk control circuit 13. In this embodiment,
When the magnetic head is positioned with respect to each track, the program shown in FIG. 6 is executed to find a pulse position capable of sending the magnetic head 5 to the regular track position with the minimum error, and to obtain the minimum pulse position at the pulse position. The magnetic head 5 is sent with an error, and feedback control is possible without providing a special feedback circuit.

(Operation) One-dot chain line 23c shown in FIG. 5 written on the magnetic disk 20
There is an error Le between the track position shown by and the position of the magnetic head 5 sent by the step motor 1 and shown by the chain double-dashed line 23b in FIG. In the present embodiment, this error is minimized as follows. According to the flowchart shown in FIG. 6A, first, the magnetic head 5 is sought by the step motor 1 to the step position corresponding to the target track 21, and then the magnetic head 5 is magnetized in the order of the scan No. shown in FIG. The disk 20 is sequentially moved from the inner circumference to the outer circumference in one direction, and the number of sectors read by the magnetic head 5 at each pulse position is totaled. As a result, the distribution as shown in FIG. 2 was obtained, and the number of readable sectors decreased as the magnetic head 5 deviated from the position of the track center written on the magnetic disk. By positioning the magnetic head 5 at the average pulse position in FIG. 2, the error between the normal track position and the position of the magnetic head 5 sent by the step motor 1 with the pulse number as a target is minimized. can do.

More specifically, the flow chart shown in FIG. 6 is cleared in step 51 by clearing the Σn register 16 and the Σxn register 17 in the memory 14, respectively, and then in step 52, the desired track N (here, The magnetic head 5 is moved to S4 in FIG. 5, which is a pulse position with respect to the position of the track 23). Next, in step 53, the magnetic head is moved toward the center of the magnetic disk 20 by four pulses. In step 54, the scan count “1” is stored in the scan register 15 in the memory 14, and the process proceeds to step 55. In step 55, the magnetic head 5 is moved to the outer peripheral side of the magnetic disk 20 by one pulse, and initially positioned at the pulse position of S1 in FIG. In addition, after the second time, positioning is performed at a position according to the number of scans.

Next, the check track sub routine of step 56 is performed. This check track subroutine is the sixth
As shown in FIG. 7B, first, in step 71, the sector flag register 18 in the memory 14 is cleared, and then in step 72, the magnetic head 5 causes the trie counter 19 in the memory 14 to detect each sector ( 9 sectors / 1
"27" is stored so that the eye field of the track) is read up to 3 times.

In step 73, the contents of the first eye field are read, then in step 74, whether the data of the read eye field has been read correctly, or whether the read eye field has been read The data corresponding to the address of the track 2
It is determined whether or not the sector corresponds to any of the sectors of No. 3, and if the result is positive, the process proceeds to step 75,
If not, the process proceeds to step 76.

Incidentally, when the data of the adjacent track is read in step 73, it is different from the data which should be written in the sector in the seeked track in step 74, so the data of the ID field is read. If it is determined that the job could not be performed, the process proceeds to step 76.

In step 75, the read sector is stored in the sector flag register 18 in the memory 14. As shown in FIG. 8, the sector flag register 18 has a 9-bit area corresponding to the position of each sector of one track, and a flag of "1" is set in the area corresponding to the read sector number.

Next, at step 76, the sector flag register 18
It is determined whether or not all the bits are flagged. If the result is positive, the check track subroutine 56 is exited and the process proceeds to step 58. If the result is negative, the process proceeds to step 77.

At step 77, the contents of the try counter 19 are changed to −
1 and then in step 78, the try counter 19
It is determined whether the content of is 0. As a result, when the result is positive, the check track subroutine 56 is exited. If NO, the process returns to step 73, the data of the next idea field is read, and the process proceeds to the next step 74. In step 58, the sector flag register 18
The number of flags in the register is counted, the number of flags is added to the content of the Zn register 16, the number of flags is multiplied by the content of the scan register 15, and the result is Σx.
-Add to the contents of n register 17.

For example, if the contents in the sector flag register 18 are as shown in FIG. 8, the number of flags is set to "5", and if the contents of the scan register 15 is "1", the number of flags is set to "5". Σn is added to the contents of the Σn register 16 again
The result of the addition is stored in the register 16. Next, multiply the number of flags “5” by the content “1” of the scan register 15,
The multiplied value is added to the contents of the Σx · n register 17, and the result is stored again in the Σx · n register 17.

Next, in step 59, "1" is added to the scan register 15, and it is determined whether or not the result is "8" in step 60. When it is not "8" yet, the process returns to step 55. The number of sectors that can be read at the next pulse position is calculated. Also, scan register 1
When the content of 5 becomes "8", in step 61 the content of the .SIGMA.x.n register 17 is divided by the content of the .SIGMA.n register 16 to obtain an average value, and the average value is rounded off to determine the positioning position.

That is, by repeating the processing from step 55 to step 59, each pulse position S1 to S7
If, for example, the ID field can be read by the number of sectors as shown in FIG. 2, Σ
4 + 8 + 9 + 7 + 2 → “30” is stored in the n register 16, and 4 × 8 is stored in the Σx · n register 17.
3 + 8 × 4 + 9 × 5 + 7 × 6 + 2 × 7 → “145” is stored. Then, at this time, since the content of the scan register 15 is determined to be "8" in step 60,
In step 61, 145/30 → 4.8 is obtained, which is rounded off and the result "5" is obtained as the average position.

Then, based on the result, the magnetic head 5 is positioned at the position of S5 in step 62.

Next, in step 63, a signal is recorded or reproduced for a desired eye field.

"Effects" As described above, the magnetic head positioning device of the present invention is provided with the means for detecting the number of sectors using the computer and the positioning means for the magnetic head. Therefore, a feedback circuit is specially required. In addition, since the magnetic disk can be accurately read and written without any inconvenience even with a low-precision magnetic head feeding mechanism, it is possible to provide an inexpensive magnetic head positioning device.

[Brief description of drawings]

FIG. 1 is a perspective view showing the structure of a magnetic head feeding mechanism in an embodiment of the present invention, FIG. 2 is a characteristic diagram showing the distribution of the number of sectors that can be read, and FIG. 3 is a block diagram showing a magnetic disk recording / reproducing apparatus. 4, FIG. 4 is a development view showing the recorded contents in each sector, FIG. 5 is a plan view showing a magnetic disk, FIG. 6 is a flow chart showing an operating state, FIG. 7 is a chart showing a scan operation, and FIG. Is a chart showing the contents of the sector flag register. 1 ... Step motor, 2 ... Feed screw, 3 ... Feed spring, 4 ... Feed base, 5 ... Magnetic head, 10 ... Magnetic disk recording / reproducing apparatus, 20 ... Magnetic disk, 21, 21
2,23 ... Track, 30 ... Computer, 40 ...
…sector.

Claims (1)

[Claims] 1. A carriage for moving a magnetic head in a radial direction of a magnetic disk on which a signal is recorded for each sector divided into a predetermined number on one track, and a feed screw screwed with the carriage. A magnetic disk recording / reproducing apparatus including a feed motor and a step motor connected to the magnetic head, and the magnetic head is positioned on each track by rotating the step motor by a predetermined number of steps for one track gap. In, the position where the pulse motor is rotated by the number of steps corresponding to the desired track position and the step motors are positioned at different positions by one step on both sides of the position, and the magnetic head can read at each of the positioning positions. The detection means for obtaining the number of sectors and the distribution of the number of sectors obtained by the detection means Serial calculated for each positioning point, the magnetic head positioning device of a magnetic disk recording and reproducing apparatus characterized by comprising a positioning means for positioning the magnetic head to the average position of the distribution.