JPS62165776A - Memory device - Google Patents

Abstract

PURPOSE:To prevent the generation of missing fault of the storage state of a disk by providing a detection circuit detecting the modulation of a reproducing signal being the result of storage information of the disk reproduced by a head. CONSTITUTION:When the floating of the head 6 is stable, since no modulation is given to the reproducing signal, the amplitude of an output signal of an amplifier 20 and the output signal of an LPF 21 are constant. The output signal of the LPF 21 is lower than the output signal of a reference voltage generation circuit 22, the output signal of a comparator 23 goes to '0' and no pulse is outputted. When the floating of the head 6 is unstable, the modulation is given to the reproducing signal and the output of the comparator 23 goes to '1' and a pulse is included in an output signal (d). An electronic computer receiving the pulse gives a command to a memory device outputting the pulse and stores information to other memory device before the head 6 is not floated from the disk 3 thereby preventing the missing fault of the storage information.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a storage device used in electronic computers, computer peripheral terminals, and the like.

[Conventional technology]

Figure 4 is an example of JP-A No. 60-101777, Electronics (April 1985 issue, hard disk, p.
59-P65, Ohmsha) and Software Knowledge (Genji Yada, 1982, P75-P83, Ohmsha), etc., is a configuration diagram showing a conventional magnetic disk device used as an example of a storage device. . In the figure, 1 is a support base, 2 is a rotating device such as a spindle motor, which is attached to the support base 1, and 3 is a disk, such as a magnetic disk, which is attached to the rotating shaft of the rotating device fi12, and is a disk such as a magnetic disk. One end of the arm 4 is fixed to the arm 5, and a head 6, such as a magnetic head for recording and reproducing, is mounted upward on the other end. 7 is a support mechanism that supports the arm 5; 9 is a ninth head moving mechanism in which the support mechanism 7 is fully assembled and moves the head 6 in the radial direction of the disk 3; 10 is a tth head moving mechanism that drives the head moving mechanism 9; This is a head drive circuit. 11 is a recording/reproducing circuit that outputs all recording signals to the head 6 in order to write information on the disk 3, and outputs all signals read from the disk 3 via the head 6 as reproduction signals; 12 is a disk drive circuit; The device 2 is driven to rotate.

Reference numeral 13 denotes a control device, which includes, for example, a central processing unit, etc., and includes a head drive circuit 10, a recording/reproducing circuit 11, and a disk drive circuit 12? It is centrally controlled, connected to a computer (not shown), inputs information to be recorded on the disc 3, and outputs all information reproduced from the disc 3.

Next, the operation will be explained. When recording or reproducing information, the disk drive circuit 12 receives all activation commands from the control device 13 and drives the rotation device 2 to rotate. When this rotating device 2 is rotationally driven and the disk 3 rotates, a viscous air flow generated on the surface of the disk 3 causes a head 6.
A downward buoyant force is generated.

This buoyant force is balanced with the pressure force of the pressure spring 4 that presses the head 6 upward, and the disk 3 is rotated while maintaining a small air space between the disk 3 and the head 6. This results in
The head 6 is arranged facing the disk 3.

In this state, when a recording or reproducing command is sent from an electronic computer (not shown) to the recording/reproducing circuit 11 via the control device 13, the recording/reproducing circuit 11 controls the recording/reproducing circuit 11 to write the data to the disk 3 via the head 6. Information is recorded or reproduced from the disc 3. Of course, at this time, the control device is used to ensure that the head 6 is positioned on a predetermined track on the disk 3.
Drive command from t13? The head moving mechanism 9 drives the support mechanism 7 in the radial direction of the disk 3 via the head drive circuit 10.

In the conventional example above, one disk is representatively shown, but multiple disks? When rotating with one rotating device,
A head is arranged for each disk. In addition, there is also a conventional example in which a control device for a magnetic disk device is incorporated into the control device for the above-mentioned computer. Furthermore, there is a conventional example in which the support mechanism is fixedly supported by a fixed mechanism, and in this case, the head moving mechanism 9 and head drive circuit 10 shown in FIG. 4 are not required.

[Problem that the invention seeks to solve]

Since the conventional recorder is structured as described above, dust generated from inside the storage device can move in and out of the tiny gap between the head and the disk, and dust can be strongly retreated from the outside of the storage device. If the head is completely hit, the head will come into contact with the disk indirectly or directly, and the head and u15 (disk) will be gradually damaged, the flying state of the head will become unstable, and after a long period of time, the head will come into contact with the disk. There were problems such as it becoming impossible to levitate and the information stored on the disk being lost.

This invention is a great solution to the problems mentioned above.
In order to prevent the loss of information stored on a disk, the objective is to obtain a storage device that can detect when the possibility of such loss has increased somewhat.

[Means for solving problems]

The storage device according to the present invention is configured such that a head reproduces information stored on a disk as a rotating storage medium to generate a reproduction signal, and a detection circuit detects the modulation of this reproduction signal. be.

[Effect]

In the storage device according to the present invention, when the head and/or the disk become progressively damaged and the flying of the head becomes unstable, the head cannot reproduce data from the disk (No. L7).
Taking advantage of the fact that the modulation increases, a detection circuit detects all of the modulation of this reproduced signal.

〔Example〕

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

In FIG. 1, the constituent elements designated by the same reference numerals 1 to 7 as in FIG. 4 are the same as those in the prior art. 20 is an amplifier,
The reproduction signal of the head 6 is fully amplified. A low-pass filter 21 receives the output of the amplifier 20, performs full-wave rectification of the input signal, integrates the full-wave rectified signal, outputs it, and extracts only the modulation component of the input signal. 22
is a reference voltage generation circuit, which generates a predetermined reference voltage that is set in advance. 23 is a comparator, the output side of the low-pass filter 21 is connected to a non-inverting input terminal, the output side of the reference voltage generating circuit 22 is connected to an inverting input terminal, and the meat input signals are compared. Signals (a) to (d) are respective output signals of each component indicated by symbols 20 to 23? It shows.

In FIG. 2, signals (a) to (d) are the same as in FIG. 1, and the waveforms of each output signal are all shown, and the one-dot chain line indicates the signal waveform when there is no modulation in the reproduced signal from the head 6. The solid line shows the signal waveform when modulation is present. However, the output signal (C) is unchanged and constant as shown by the two-dot chain line. In FIG. 1, other parts having the same configuration as the conventional example are not shown.

Next, the operation will be explained. In such a storage device, when the head 6 is in a stable flying state, there is no modulation in the reproduction signal of the head 6, so the amplitude of the output signal (a) of the amplifier 20 and the output signal (a) of the low-pass filter 21 are
b) becomes a waveform with a constant level as indicated by a dashed line, and the output signal (b) of the low-pass filter 21 is always lower than the output signal (C) of the reference voltage generation circuit 22, and the output signal of the comparator 23 ( d) becomes a logic "0" signal, and no pulse is output from now on.

If the head 6 and/or the disk 3 are gradually damaged and the flying of the head 6 becomes unstable, the distance between the head 6 and the disk 3 will constantly change during information reproduction, so the amplitude of the signal reproduced by the head 6 will change. Modulation, which can be called modulation, occurs, and the output signal (a) of the amplifier 20 and the output signal (b) of the low-pass filter 21 have undulating waveforms as shown by the solid line in FIG.
The output signal (b) of the reference voltage generation circuit 22 is the output signal (b) of the reference voltage generation circuit 22.
C) There are times when the temperature rises, and at this time the comparator 23
Since the output of the comparator 23 is inverted and becomes a logic "1" signal, the output signal (d) of the comparator 23 includes a pulse.

When the pulse of the output signal (d) of the comparator 23 is sent to an electronic computer (not shown), this computer immediately issues a command to the storage device that outputs the pulse, and the head 6 becomes unable to fly above the disk 3. By first downloading the information from the disk 3 and storing all the information in another storage device (not shown), it is possible to completely prevent the loss of stored information.

Note that in the above embodiment, the low-pass filter 21 was used, but instead of this, a reproduced signal sent to the head 6 may be used. Rectify with a rectifier circuit, this rectifier No. 5? It is also possible to perform envelope detection using an envelope detector.

FIG. 3 shows another embodiment, in which numeral 6 denotes a head, which is the same as the conventional one, and the disk and other components shown in FIG. 1 are not shown entirely. Code 22.23, output signal (C) (d)
is the same as in FIGS. 1 and 2. Reference numeral 24 denotes an automatic gain control amplifier, which inputs all the reproduced signals from the head 6, and is designed so that the gain becomes lower (or higher) as the control voltage (e) (shown in FIG. 2) becomes higher (or lower). As shown in Fig. 2, the control voltage (e) increases (or As shown in Figure 3 (B), the output signal (
f) is always a constant value. The comparator 23 inputs the control voltage (e) of the automatic gain control amplifier 24 to the non-inverting terminal side, and the base 's4. 'Output signal of WL pressure generation circuit 22 (
C)? Input to the inversion terminal side and compare the meat input signals. When there is (or is not) modulation in the reproduction signal of the head 6, the control voltage (e) becomes as shown in the solid line (or the dashed line) shown in Fig. 2, and the same operation as in Fig. 1 is expected. Ru.

In each of the above embodiments, the head 6'fe is used for recording and reproducing, but it may be used exclusively for reproducing. However, in this case, a reproducing circuit is used instead of the recording/reproducing circuit.

In addition, although the above embodiments have been described with reference to a magnetic disk device, it is also possible to use a recording device as a storage device using a well-known optical method, magneto-optical method, laser method, electric field method, electric charge method, or other method. Other storage devices may be used, and the same effects as in the above embodiments will be achieved.

〔Effect of the invention〕

As described above, the present invention is configured to detect all modulations of the waveform of the reproduced signal by the head that reads information stored on the disk. It is possible to detect that there is a slight increase in the possibility of an accident in which information stored on a disk is lost, and there is an effect that such loss accident can be completely prevented.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a storage device according to an embodiment of the present invention;
2 is a signal waveform diagram of each part in FIG. 1, etc., FIG. 3 is a block diagram showing another embodiment of the present invention, and FIG. The waveform diagram and FIG. 4 are configuration diagrams showing a conventional storage device. In the figure, 2 is a rotating device, 3 is a disk, 6 heads, 20 is an amplifier, 21 is an extraction circuit, 22 is a reference voltage generation circuit, 23 is a comparator, and 24 is an automatic gain control amplifier. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (5)

[Claims] (1) Rotating a disk as a storage medium with a rotating device,
In a storage device in which a head for recording and reproducing information on the disk is disposed facing the recording surface of the disk, modulation of the waveform of a reproduced signal by the head that reads information recorded on the disk is performed. A storage device characterized by being provided with a detection circuit for detecting. (2) As the detection circuit, the reproduction signal is passed through an extraction circuit that extracts the modulation component from the reproduction signal of the head, and the output voltage of this extraction circuit and the reference voltage of the reference voltage generation circuit are compared by a comparator. A storage device according to claim 1, characterized in that: (3) The storage device according to claim 2, wherein a low-pass filter is used as the extraction circuit. (4) The extraction circuit rectifies the reproduced signal with a rectifier circuit, and envelope-detects the rectified signal with an envelope detector.
Storage device described in section. (5) The detection circuit is characterized in that the reproduced signal from the head is input to an automatic gain control amplifier, and the control voltage of the automatic gain control amplifier and the reference voltage of the reference voltage generation circuit are compared by a comparator. A storage device according to claim 1.