JPS63276758A - Storage device - Google Patents

Abstract

PURPOSE:To prevent the information vanishing of a recording medium beforehand by providing a voltage fluctuation allowance detecting circuit to detect that the scope of the power source in which a positioning error is not detected is narrower than a prescribed scope and outputs an abnormality detecting signal. CONSTITUTION:An electronic computer 19 outputs an instruction to supply a power source voltage lower than a rated voltage to a voltage fluctuation allowance detecting circuit 21 and judges an action allowance by the presence and absence of an abnormality detecting signal D corresponding to speed information. When a friction resistance between a head 4 and a recording medium 3 is enlarged, the action allowance for positioning the head 4 is narrower, the speed information A is remarkable in fluctuation, the positioning of the head 4 is completed by a time T2 shorter than a regular time T1, an error detecting signal C is outputted from an error detecting circuit 20, and the voltage fluctuation allowance detecting circuit 21 outputs the abnormality detecting signal D and informs that the scope of the power source voltage in which the positioning error of the head 4 is not detected, is made narrower than a prescribed scope.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a storage device used in an electronic computer or computer peripheral equipment, etc., and particularly to a storage device that prevents information from being lost due to a head crash. It is.

[Prior Art] FIG. 3 is a side view showing a shell-like magnetic disk device described in, for example, Japanese Patent Laid-Open No. 101777/1983.

In the figure, (1) is a support base, (2) is a rotating device consisting of a spindle motor installed on the support platform (1), and (3) is a magnetic device attached to the rotating shaft of the rotating device (2). It is a recording medium consisting of a disk.

(4) is a head placed facing the recording surface of the recording medium (3), (5) is a pressure spring for biasing the head (4) against the recording surface, and (6) is a pressure spring. This is an arm that supports one end of the spring (5).

(7) is an actuator that moves and positions the head (4) in the radial direction of the recording medium (3);
) for supporting and fixing one end of the carriage (8), a bearing (9) for guiding and moving the carriage (8) on the support base (1), and a cylindrical coil (10) provided at one end of the carriage (8). ), a magnet (11) placed opposite the coil (10), and a yoke for positioning the magnet (11)
12).

(13) is a sensor for detecting the position of the head (4), and includes a transducer (14) fixed to the support base (1);
It consists of an optical linear scale (15) provided on a carriage (8).

FIG. 4 is a block diagram showing a storage device in which a drive control section is added to the magnetic disk device of FIG. 3.

In the figure, (16) is a speed demodulator that differentially shapes the position information from the sensor (13) to detect the positioning speed of the head (4), and A is the output signal of the speed demodulator (16), that is, the head (4). Speed information (17) indicating the moving speed of the actuator (7) is a servo circuit that drives the actuator (7) based on the position information from the sensor (13) and the speed information A from the speed demodulator (16).

(18) is a glue write circuit for recording or reproducing information on the recording medium (3) via the head (4);
) is an electronic meter that outputs a movement positioning command to a servo circuit (17) and outputs a recording/reproducing command to a read/write circuit (18).

(20) is an error detection circuit that detects a positioning error based on the output signal of the servo circuit (17), for example, the positioning time B, and the positioning time B of the head (4) due to disturbance etc.
is abnormally long, the error detection signal C is electronically calculated fi (
19>.

In addition, the detection of such positioning error is performed during the positioning time B.
Not only when the length of the head (4) is abnormal, but when the position of the head (4) or sensor (13) is slightly deviated from the recording medium (3) 1-rack position, the recording medium played by the head (4) The appropriateness is also used when the location address in (3) is incorrect.

Next, while referring to the waveform diagram in FIG.
The operation of the conventional storage device shown in the figure will be explained.

When the recording medium (3) is rotated by the rotating device (2), buoyancy is generated on the head (4) due to the viscous air flow generated on the surface of the recording medium (3). As this buoyant force balances with the biasing force of the pressure spring (5), the recording medium (3) continues to rotate while maintaining a small gap between it and the head (4).

Here, when a movement positioning command is output from the electronic computer (19) to the servo circuit (17), a current flows through the coil (10), and the magnetic circuit consisting of the magnet (11) and the yoke (12) The force according to Fleming's left-hand rule acts. Therefore, the carriage (8) is driven, the head (4) is moved and positioned while seeking the information track of the recording medium (3), and at the same time, the servo circuit (17)
) is the head (4) based on the position information and speed information A.
to the commanded position.

After the movement and positioning of the head (4) is completed, the electronic meter'a
, a recording/reproducing command is output from the read/write circuit 18), and the head (4) records information on the recording medium (3) or reproduces information from the recording medium (3).

At this time, the error detection circuit (20) detects the head (
4) Detect the presence or absence of a positioning error.

If a positioning error of the head (4) is detected,
The error detection circuit (20) outputs the error detection signal C, and the electronic computer (19) redoes the movement positioning until the error detection signal C disappears.

-m, when the head (4) is flying normally, the frictional resistance between the head (4) and the recording medium (3) is a small value determined only by the viscous air flow and the bearing (9). Therefore, there is a wide margin for positioning the head (4), and the speed information A has a trapezoidal waveform as shown by the broken line in FIG.

On the other hand, dust generated from inside the storage device
If the actuator (7) moves in and out of the minute gap between the actuator (7) and the head (4), or if the head (4) comes into contact with the recording medium (3) and gets caught due to strong vibrations or shocks from outside the storage device, the actuator (7) Since the speed of the vehicle changes, the speed information A becomes like a solid line.

However, if the power supply voltage is the rated voltage, even if there is an abnormal increase in frictional resistance, the head (4) will follow the hunting while reversing the hunting as shown by the solid line, so the positioning time B
is regular time T. Does not change from

In other words, the rated voltage has a large margin for the load on the speed demodulator (16), so there is little voltage fluctuation in the speed demodulator (16), and even if the head (4) gets caught on the recording medium (3) to some extent, it will not detect an error. Signal C is never output.

[Problems to be Solved by the Invention] As described above, since the conventional storage device always supplies the rated voltage, an abnormal increase in frictional resistance occurs between the head (4) and the recording medium (3). Even if this occurs, it cannot be detected and the head (4) or recording medium (3) will be damaged, and after a long period of time, the head (4) will fall onto the recording medium (3) and the recording medium (3) will be damaged.
There was a problem that the information in 3) was lost.

The present invention was made to solve the above-mentioned problems, and an object of the present invention is to provide a storage device that can prevent accidents in which information on a recording medium is lost.

[Means for Solving the Problems] A storage device according to the present invention detects the presence or absence of a positioning error when the power supply voltage is different from the rated voltage, and detects the presence or absence of a positioning error when the power supply voltage is not detected as being narrower than a predetermined range. This system is equipped with a voltage fluctuation margin detection circuit that detects the abnormality and outputs an abnormality detection signal.

[Function] In this invention, a power supply voltage different from the rated voltage is supplied to increase the variation in speed information with respect to load fluctuation, and the state of the power supply voltage when a positioning error is detected is detected and operated. By detecting that the margin has become narrower than a predetermined range, it is determined whether the frictional resistance between the head and the recording medium is increased due to scratches on the head or the recording medium,
To store information on a recording medium in another storage device before the head falls onto the recording medium.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings. 1st
The figure is a block diagram showing one embodiment of the present invention.
), (4), (7), (13), (16) to (20) are the same as described above. Further, the configuration of the parts not shown is the same as that in FIG. 3.

(21) is a voltage fluctuation margin detection circuit, and the electronic calculation If
f (19) to vary the power supply voltage and, based on the error detection signal C from the error detection circuit (20), detect that the fluctuation range of the power supply voltage in which positioning errors are not detected has become narrower than a predetermined range. It also outputs an abnormality detection signal. In this embodiment, as will be described later, the voltage fluctuation margin detection circuit (21) supplies a power supply voltage lower than the rated voltage.

Next, the operation of the embodiment of the present invention shown in FIG. 1 will be described with reference to the waveform diagram in FIG. 2.

During normal positioning (seek) operation, the head (4) is moved and positioned at the rated voltage as described above, so there is no frictional resistance between the head (4) and the recording surface of the recording medium (3). Even if an abnormal increase occurs, the error detection circuit (2
Error detection signal C is not output from 0) (see Figure 5).
.

When determining an abnormal increase in frictional resistance, electronic calculation 1!
1 (19) outputs a command to supply a power supply voltage lower than the rated voltage to the voltage fluctuation margin detection circuit (21), and determines the operating margin based on the presence or absence of an abnormality detection signal corresponding to the speed information A at this time. to decide.

At this time, if the head (4) is flying normally relative to the recording medium (3), the speed information A will have a trapezoidal waveform with gradual rises and falls, as shown by the broken line in FIG. . Therefore, the positioning time B becomes the normal time T1, and the error detection signal C and abnormality detection signal are not output (
(see dashed line).

On the other hand, the head (4) or recording medium (3) begins to get scratched,
When the frictional resistance between the head (4) and the recording medium (3) increases by the amount of dragging or catching, the operational margin for positioning the head (4) becomes narrower, and the speed information A becomes as shown by the solid line. Become. At this time, the variation in the speed information A due to the increase in frictional resistance becomes more noticeable than in the case of the rated voltage shown in FIG. 5, and the positioning time B becomes shorter than in the normal state.

Therefore, in the normal time T, the head (4) in the shorter time T2.
, the error detection circuit (20) outputs an error detection signal C. Based on this error detection signal C,
The voltage fluctuation margin detection circuit (21) outputs an abnormality detection signal indicating that a positioning error has been detected when determining an abnormal increase in frictional resistance to the electronic computer (19). That is, the voltage fluctuation margin detection circuit (21) notifies the electronic computer (19) that the range of power supply voltages in which no positioning error of the head (4) is detected has become narrower than a predetermined range.

As a result, the electronic computer (19) immediately issues a command to reproduce information from the recording medium (3) before the head (4) falls onto the recording medium (3), and transfers this information to another recording medium. (not shown). In this way, the recording medium (3
) information loss accidents can be prevented.

The operation of lowering the power supply voltage below the rated voltage to determine whether there is an abnormality in frictional resistance is performed once every few months, depending on the frequency of use of the storage device and the frequency of crashes of the head (4).
It is carried out once in a while. This judgment operation is performed by the electronic meter 3Ef
This may be done automatically by a program in i(19), or may be done periodically by an operator.

The function of changing the power supply voltage as described above can be easily executed by a general electronic computer (19), and the voltage fluctuation margin detection circuit (21) can be configured with a digital circuit. The entire device does not become particularly large.

In the above embodiment, a case has been described in which the power supply voltage is lowered when determining an abnormal increase in frictional resistance and a range of power supply voltage (operation margin) in which positioning errors are not detected is detected.
The same effect can be achieved even if the power supply voltage is increased to determine the operating margin.

In addition, although the case where the positioning operation margin of the head (4) is detected by the error detection circuit (20) and the voltage fluctuation margin detection circuit (21) has been described, the one-shot I/multi circuit,
The detection may be performed using a timer circuit, a transmitter, a microcomputer, etc.Although the case where the carriage (8) moves linearly is shown, other positioning drive methods such as oscillating or rotational movement may also be used. It's okay.

Further, although the position of the head (4) is detected by the sensor (13), the head (4) itself or another head may be detected.

Furthermore, although a storage device using a magnetic disk device has been described, a recording device, a recording device, or a storage device using an optical method, a magneto-optical method, a laser method, an electric field method, an electric charge method, or other methods may be used. .

[Effects of the Invention] As described above, according to the present invention, it is possible to detect the presence or absence of a positioning error when the power supply voltage is different from the rated voltage, and to detect when the range of power supply voltages in which no positioning error is detected is narrower than a predetermined range. By providing a voltage fluctuation margin detection circuit that detects and outputs an abnormality detection signal, it is possible to increase fluctuations in speed information in response to load fluctuations and detect increases in frictional resistance between the head and the recording medium. Information on the recording medium can be stored in another storage device before the head falls onto the recording medium, an effect that can only be obtained with a memory bag that prevents information from being lost.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a waveform diagram for explaining the operation of FIG. 1, FIG. 3 is a side view showing a general magnetic disk device, and FIG. FIG. 5 is a block diagram showing a conventional storage device, and FIG. 5 is a waveform diagram for explaining the operation of FIG. 4. (2)...Rotating device (3)...Recording medium (
4) Head (20) Error detection circuit (21) Voltage fluctuation margin detection circuit B Positioning time C Error detection signal D
... Abnormality detection signal T1 ... Normal time plane, in the figure,
The same reference numerals indicate the same or equivalent parts. Figure 1 Figure 2 Abnormality detection signal 1111 --- Figure 3 Figure 4 Speed information A ・Position @ fertilization time B Erroneous Q detection time C Figure 5

Claims (3)

[Claims] (1) A recording medium that is rotationally driven by a rotating device, a head that is placed opposite to the recording surface of the recording medium for recording or reproducing information, and detects errors in the positioning of this head and generates an error detection signal. In a storage device equipped with an output error detection circuit, the presence or absence of a positioning error is detected when a power supply voltage is different from a rated voltage, and the range of power supply voltages in which the positioning error is not detected is narrowed than a predetermined range. 1. A storage device comprising a voltage fluctuation margin detection circuit that outputs an abnormality detection signal. (2) The storage device according to claim 1, wherein the voltage fluctuation margin detection circuit outputs an abnormality detection signal based on an error detection signal when the power supply voltage is lower than the rated voltage. (3) The storage device according to claim 2, wherein the voltage fluctuation margin detection circuit outputs an abnormality detection signal when the positioning time is shorter than the regular time when the power supply voltage is lower than the rated voltage. .