JPH0612562B2 - Magnetic recording / reproducing device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus which does not generate noise due to a track positioning error of a magnetic head and does not cause an increase in overwrite noise.

[Technical background of the invention and its problems]

Recently, a floppy disk device (FDD) using a so-called floppy disk, which is a flexible rotating magnetic medium, has become widespread as an external information recording device for various information processing devices. In this FDD, a magnetic head for magnetically recording / reproducing information on / from the floppy disk has a conventional recording / reproducing gap 1 directly involved in magnetic recording / reproducing of information and a track positioning error of the magnetic head as shown in FIG. Erasing gaps 2a and 2b are provided for the purpose of trimming in order to avoid mixing of the previous data. The recording / reproducing gap 1 is for recording new data 4 while rewriting the previous data 3 as shown in FIG. 1, and the erasing gaps 2a and 2b are for the previous data 3 which was not rewritten in the recording / reproducing gap 1. The remaining portion 3a is erased to prevent the previous data 3 from being mixed into the new data 4 as described above.

However, in recent years, in order to further increase the information recording density on a floppy disk, the coercive force of the magnetic layer of the floppy disk is improved, the thickness of the magnetic layer is reduced, and the width of the recording / reproducing gap in the magnetic head is reduced. Various attempts have been made. In the current high density type, the thickness of the magnetic layer is set to about 1 μm and the gap width is set to about 1.7 μm. However, if the width of the gap becomes smaller than the thickness of the magnetic layer as a result of further improvement in order to improve the information recording density in this way, it becomes difficult to perform conventional magnetic saturation recording. Therefore, when unsaturated recording is performed, the previous data 3 is not completely erased when the data 3 is rewritten to new data 4 as shown in FIG. 1, that is, the overwriting noise is eventually increased. Be invited.

In order to solve these problems, a magnetic head having an erasing gap 5 having a wide gap width at a position preceding the recording / reproducing gap 1 is considered as shown in FIG. The preceding wide type erasing gap 5 is for erasing in advance while trimming the data 3. However, the use of such a magnetic head has the following problems in terms of extensibility and diversion with the interface and recording format in the current FDD.

That is, the current signal recording format in FDD generally comprises one sector, as shown in FIG. 3, with the ID section 6, the first gap section 7, the data section 8 and the second gap section 9. The first and second gap portions 7 and 9 are used as a buffer, and these gap portions are
The drive of the recording / reproducing gap 1 and the erasing gaps 2a, 2b is controlled by using a write enable signal which is turned on / off at 7,9. Therefore, when such a signal is used as it is to drive the magnetic head of the preceding wide erasing method, as shown in FIG. There is a problem that the unerased portion 8a remains in No. 8. Then, in the unerased portion 8a, signal overwriting occurs, which eventually leads to the above-mentioned noise problem.

[Object of the Invention]

The present invention has been made in consideration of such circumstances, and an object of the present invention is to make it possible to improve the information recording density without causing a problem such as overwriting noise and the like, and it is of a practical and practical use. An object is to provide a high magnetic recording / reproducing device.

[Outline of Invention]

The present invention relates to a magnetic recording / reproducing apparatus using a magnetic head having a recording / reproducing gap and an erasing gap arranged at a position preceding the recording / reproducing gap on the magnetic recording medium, when the information is recorded on the magnetic recording medium. Is provided with a control means for driving at a timing earlier than the recording / reproducing gap. Further, it is preferable that the magnetic head has an erase gap wider than the recording / reproducing gap.

The control unit detects and erases the ID section of one sector composed of the ID section, the first gap section, the data section and the second gap section of the magnetic recording medium, for example, when information is recorded on the magnetic recording medium. An erase gate signal for driving the gap is generated, and further, a write gate signal for driving the recording / reproducing gap is generated by detecting the end of the first gap portion.

〔The invention's effect〕

Thus, according to the present invention, since the erasing gap located at a position preceding the recording / reproducing gap is driven prior to the recording / reproducing head, no unerased portion remains in the data portion as in the conventional case, and therefore overwriting occurs. No overwriting noise occurs. Therefore, the information recording density can be easily improved without reducing the thickness of the magnetic layer of the magnetic disk recording medium. Further, since the thickness of the magnetic layer is not reduced, it is possible to alleviate the difficulty in manufacturing the magnetic layer and to improve the durability.

Example of Invention

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

FIG. 4 shows the concept of magnetic head drive in the apparatus of the embodiment, and FIG. 5 is a schematic configuration diagram of the main parts of the apparatus of the embodiment. The same parts as those of the conventional device will be described with the same reference numerals.

This device is provided at a position preceding the recording / reproducing gap 1 that is directly involved in magnetic recording / reproducing of information.
A so-called leading wide erasing type magnetic head having a structure in which an erasing gap 5 having a wider gap width is provided is used, and the recording / reproducing gap 1 and the erasing gap 5 are driven by different signals.

That is, reference numeral 11 in FIG. 5 denotes a drive circuit board for a magnetic head in a magnetic disk device, which has a drive coil 1a for the recording / reproducing gap 1 and a drive coil for the erasing gap 5.
5a and drive circuits 12 and 13 for these drive coils 1a and 5a are provided. A signal reproduced from the recording / reproducing gap 1 via the drive coil 1a is amplified and output via a reproducing amplifier 14. Again 15
Is a logic circuit that controls the entire operation of the drive circuit board 11, and the drive circuits 12 and 13 under the control of the logic circuit 15 and the drive circuit 16 that drives the mechanism system of the magnetic disk device are Each is designed to work. The drive circuit board 11 configured in this way is similar to the conventional magnetic disk device.

On the other hand, the feature of the present device resides in that the control unit 21 for controlling the drive of the drive circuit board 11 is configured as follows. This control unit 21 is generally called FDC, and provides various control signals for controlling the entire FDD, such as controlling the data format of the recording signal of the magnetic disk, checking data errors, and driving mechanism of the FDD. Occur. This FDC21 is characterized by a write / write control for controlling the drive of the recording / reproducing gap 1.
The point is that the enable signal WE is generated and the erase enable signal EE for controlling the driving of the erase gap 5 is generated separately from this signal. These enable signals WE and EE are applied to the drive circuit of the drive circuit board 11.
12 and 13 are respectively applied to control the operation of the drive coils 1a and 5a. The FDC 21 also supplies a command / status signal and the like to the logic circuit 15.

Therefore, the FDC 21 detects the I signal from the signal detected from the floppy disk through the recording / reproducing gap 1.
The information described in the D section 6 is identified, and it is determined whether or not the sector is a recording / reproducing target sector (ID detection section 22), and the write enable signal or erase enable is performed according to the determination result. FD by generating signals
The recording / reproducing operation of D is controlled. That is, FDC21
The D detection unit 22 detects the corresponding sector to be recorded / reproduced, detects the first gap portion 7 thereof, and detects the WE signal generation unit.
At 23, the write enable signal WE is generated. The generation of the write enable signal WE is similar to that of the conventional device, but at this time, the ID section 6 is detected and the erase enable signal is generated by the EE signal generating section 24 prior to the generation of the write enable signal WE. It is different from the conventional one in that EE is generated. That is, the write enable signal WE and the erase enable signal EE are generated at independent timings.

On the other hand, the information recording format of the floppy disk is set so that the data length areas of the first and second gap portions 7 and 9 are longer than the physical lengths of the recording / reproducing gap 1 and the erasing gap 5. There is. Such a distance relationship between the gap portions 7 and 9 and the signals W
Depending on the generation timings of E and EE, when the recording / reproducing gap 1 is located at the position of the first gap portion 7, as shown in FIG. 4, the erasing gap 5 is started to be driven.

Therefore, the erase gap 5 is driven before it reaches the position of the data section 8, so that the data section 8 is surely erased from the beginning thereof. While the previous data is erased by the erase gap 5, when the recording / reproducing gap 1 reaches the data portion 8, the write enable signal WE is generated by the detection of the first gap portion 7. Then, the drive of the recording / reproducing gap 1 is started, and the magnetic recording of information is performed. When the information recording on the data section 8 is completed and the magnetic head reaches the second gap section 9, the generation of the enable signals WE and EE is stopped and the driving of the gaps 1 and 5 is stopped. .

Thus, according to the device thus configured, the light
Since the erase enable signal is generated to drive the erase gap 5 prior to the enable signal, it is possible to securely erase the previous data recorded in the data section 8 and then record new data. Therefore, it is possible to easily improve the information recording density without causing the problems of conventional overwriting and the generation of noise. Moreover, the preceding wide erasing method can be applied without changing the data format of the conventional so-called tunnel erase method. However, in this case, it goes without saying that it is necessary to sufficiently consider the physical distances between the data length regions of the first and second gaps and the respective gaps of the magnetic head. Also, the erase enable signal is F
Since it is sufficient to use the ID detection result of the ID detection unit of the DC, it is relatively easy to control the signal generation. Therefore, there is an effect that the device configuration is not complicated.

The present invention is not limited to the above embodiments, and various modifications can be carried out without departing from the scope of the invention.

[Brief description of drawings]

FIGS. 1 and 2 are views for explaining the structure and action of the gap of the magnetic head, FIG. 3 is a view for explaining problems in the conventional information recording, and FIG. 4 is a view for explaining the present invention. FIG. 5 is a diagram showing a form of information recording in one embodiment, and FIG. 5 is a diagram showing a schematic configuration of a main part of an embodiment apparatus. 1 ... Recording / playback gap, 2a, 2b, 5 ... Erase gap,
6 ... ID part, 7 ... first gap part, 8 ... data part, 9 ... second gap part.

Claims (5)

[Claims] 1. A magnetic head having a recording / reproducing gap and an erasing gap arranged at a position preceding the recording / reproducing gap on the magnetic recording medium, and the erasing gap is recorded when the information is recorded on the magnetic recording medium. A magnetic recording / reproducing apparatus comprising: a control unit that is driven at a timing earlier than the reproduction gap. 2. The magnetic recording / reproducing apparatus according to claim 1, wherein the erase gap has a wider gap width than the recording / reproducing gap. 3. The ID of one sector, which is constituted by an ID section, a first gap section, a data section and a second gap section of the magnetic recording medium when information is recorded on the magnetic recording medium. A write gate signal for driving the write / read gap by detecting the end of the first gap portion. The magnetic recording / reproducing apparatus according to claim 1, wherein 4. The magnetic recording according to claim 3, wherein the first gap portion has a data area longer than a physical distance between the recording / reproducing gap and the erasing gap. Playback device. 5. The control means according to claim 3, wherein the control means detects the end of the data portion of the magnetic recording medium to stop the generation of the first and second signals. Magnetic recording / reproducing device.