JPH04358352A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To save power by adjusting the starting current of a spindle motor corresponding to the state of a magnetic head in the case of starting at the magnetic disk device to load the magnetic head onto a magnetic disk when starting a spindle motor. CONSTITUTION:A head supporter holding means 8 is provided to set a magnetic head 2 in a state away from the surface of a magnetic disk 1, a head separation detecting means 15 is provided to detect the state of the magnetic head at the time of starting the rotation of the magnetic disk, and a spindle torque switching means 14 is provided to switch the starting torque of the spindle motor according to the state of the magnetic head. Thus, the magnetic disk device can be obtained to save power by reducing the starting current when the magnetic head is separated from the magnetic disk by the head supporter holding means in the case of starting.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk drive that adjusts the starting torque of a magnetic disk when starting its rotation.

0002

2. Description of the Related Art In recent years, magnetic disk drives have become smaller, lighter, and more power efficient. In particular, miniaturized magnetic disk drives are sometimes carried around, such as being installed in notebook personal computers, and therefore need to be shock resistant. For this reason, magnetic disk drives are beginning to appear in which the magnetic head is kept away from the magnetic disk surface when information is not being recorded or reproduced.

An example of the above-mentioned conventional magnetic disk device will be explained below with reference to the drawings.

FIG. 2 is a plan view of a conventional magnetic disk device.
FIG. 3 shows a configuration block diagram including a sectional view of a conventional magnetic disk device. In FIGS. 2 and 3, 1 is a magnetic disk. 2 is a magnetic head, 3 is a flexure which is a head support body, and 4 is a rotary actuator which is a head moving means, which is composed of a carriage 5 and a voice coil motor (hereinafter referred to as VCM) 6, and which moves the magnetic head around a rotation axis 7. is moved in the radial direction of the magnetic disk. 8
is a flexure holding member which is a head support holding member. 9 is a spindle motor, and 10 is a spindle drive circuit which is a spindle drive means. The operation of the magnetic disk device configured as described above will be described below.

When the magnetic disk drive is in a standby state, the magnetic disk 1 is stopped, and the flexure 3 supporting the magnetic head 2 is held on the flexure holding member 8. At this time, the magnetic head 2 is in a separated state (A in FIG. 3) away from the surface of the magnetic disk 1.

When recording and reproducing information, the controller 11 first sends a spindle start/stop signal line 1 to the spindle drive circuit 10 in order to rotate the magnetic disk 1.
Send a start command through 2. The spindle drive circuit 10 supplies a drive current of 1 to the spindle motor in response to a start command.
3, the magnetic disk 1 is rotated. At this time, since the magnetic head 2 is separated from the magnetic disk 1, the load on the spindle motor is light. When the magnetic disk 1 reaches a steady rotation speed, the carriage 5 is driven by the VCM 6 to move the magnetic head 2 toward the magnetic disk 1. At this time, since the flexure 3 slides off the flexure holding member 8, the magnetic head 2 descends onto the surface of the magnetic disk 1 (B in FIG. 3). When the magnetic head 2 descends onto the surface of the magnetic disk 1, the rotary actuator 4 moves the magnetic head 2 to a target track in order to record and reproduce information.

[0007] Once information has been recorded or reproduced, if a command to record or reproduce the next information is not issued for a predetermined period of time,
The controller 11 puts the magnetic disk device into a standby state to save power. To enter the standby state, first, the rotary actuator 4 moves the magnetic head 2 toward the outer circumference of the magnetic disk 1 . When the magnetic head 2 reaches the outer circumference, the flexure 3 rides on the flexure holding member 8. Therefore, the magnetic head 2 separates from the surface of the magnetic disk 1, and information on the magnetic disk 1 cannot be reproduced. When the reproduction signal cannot be detected from the magnetic head 2,
The rotary actuator 4 stops moving, and the controller 11 sends a stop command to the spindle drive circuit through the spindle start/stop signal line 12 to stop the spindle motor. This puts the magnetic disk device into a standby state. (For example, Japanese Patent Application Laid-Open No. 2-312075)

[0008]

[Problem to be Solved by the Invention] However, in the above configuration, when the magnetic head is on the magnetic disk,
If the power supplied to the magnetic disk drive is cut off, the rotary actuator cannot move the magnetic head to the standby position (A in Figure 4), so the magnetic head remains in contact with the magnetic disk. The spindle motor stops in this state. Furthermore, even if some method is used to move the magnetic head to the standby position when the power is turned off, the rotary actuator will require a considerable driving force to ride on the flexure holding member, so it will not move completely to the standby position. There is no guarantee that it will be possible. Therefore, when the power is turned on again and the spindle motor starts, the magnetic head and magnetic disk are in contact, so the frictional force is large, and the starting torque of the spindle motor is larger than when starting from a normal standby state. It becomes necessary. For this reason, the current flowing through the spindle motor must be set by estimating a large amount assuming a case where the starting torque is large, and a large drive current flows even when starting from a normal standby state, increasing power consumption. There was a problem.

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a magnetic disk drive that can optimally set the spindle motor drive current amount at startup and reduce power consumption.

0010

Means for Solving the Problems In order to solve the above problems, the magnetic disk drive of the present invention provides a magnetic disk drive in which a spindle driving means for driving a spindle motor and a magnetic head are separated from a magnetic disk surface by a head support holding member. The apparatus is equipped with head separation detection means for detecting whether the magnetic head is separated, and spindle torque switching means for switching the starting torque of the spindle motor depending on whether or not the magnetic head is separated.

[0011]

[Operation] With the above-described configuration, the present invention detects the position of the magnetic head when starting the spindle motor by the head separation detection means, and switches the starting current according to the separation state by the spindle torque switching means, so that the optimum starting current can be obtained. This can be set.

0012

DESCRIPTION OF THE PREFERRED EMBODIMENTS A magnetic disk drive according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a block diagram of a magnetic disk device according to an embodiment of the present invention. In FIG. 1, 1 is a magnetic disk, 2 is a magnetic head, 3 is a flexure that is a head support, and a rotary actuator (not shown) that is a head moving means moves the magnetic head 2 in the radial direction of the magnetic disk 1. let 8 is a flexure holding member which is a head support holding member. 9 is a spindle motor, and 10 is a spindle drive circuit which is a spindle drive means. 14 is a spindle torque switching circuit which is a spindle torque switching means. Reference numeral 15 denotes head separation detection means, which includes a sensor 16 and a load/unload detection circuit 17.

The operation of the magnetic disk device configured as described above will be explained below using FIG. 1.

First, when the magnetic disk drive is in a standby state, the magnetic disk 1 is stopped, and the flexure 3 supporting the magnetic head 2 is held on the flexure holding member 8. At this time, the magnetic head 2 is in a separated state (A in FIG. 1) away from the surface of the magnetic disk 1. A sensor 16 attached to the flexure holding member 8 is like a pressure sensor, for example, and generates a voltage due to the pressure of the flexure, whereby the load/unload detection circuit 17 recognizes the separation state of the magnetic head and notifies the controller.

When recording and reproducing information, the controller 11 first instructs the spindle torque switching circuit 14 to switch the switch 18 in order to rotate the magnetic disk 1. As a result, the spindle torque switching circuit 14 sets the switch 18 to the R1 side to reduce the spindle drive current. Next, a start command is sent to the spindle drive circuit 10. In response to the start command, the spindle control circuit 19 in the spindle drive circuit 10 generates a predetermined voltage for starting the spindle motor, sends it to the amplifier 20, and causes the drive current 13 to flow to the spindle motor 9 through the output amplifier 21. The drive current 13 is converted into a voltage by a resistor R1 in the spindle torque switching circuit 14 and fed back to the amplifier 20. The drive current at which this feedback voltage and the voltage generated by the spindle control circuit 19 are the same becomes the maximum drive current, and the drive current is limited so that no more drive current flows. The magnetic disk 1 is rotated by the drive current 13, but at this time, since the load on the spindle motor is light, the drive current 13 can rotate even if it is small. When the magnetic disk 1 reaches a steady rotation speed, the carriage 5 is driven by the VCM 6 to move the magnetic head 2 toward the magnetic disk 1. At this time, since the flexure 3 slips off the flexure holding member 8, the magnetic head 2 descends onto the surface of the magnetic disk 1 (B in FIG. 1). When the magnetic head 2 descends onto the surface of the magnetic disk 1, the rotary actuator 4 moves the magnetic head 2 to a target track in order to record and reproduce information.

[0017] Once information has been recorded or reproduced, if a command to record or reproduce the next information is not issued for a predetermined period of time,
The controller 11 puts the magnetic disk device into a standby state to save power. To enter the standby state, first, the rotary actuator 4 moves the magnetic head 2 toward the outer circumference of the magnetic disk 1 . When the magnetic head 2 reaches the outer circumference, the flexure 3 rides on the flexure holding member 8. Therefore, the magnetic head 2 separates from the surface of the magnetic disk 1, and information on the magnetic disk 1 cannot be reproduced. When the reproduction signal cannot be detected from the magnetic head 2,
The rotary actuator 4 stops moving, and the controller 11 sends a stop command to the spindle drive circuit through the spindle drive/stop signal line 12 to stop the spindle motor. This puts the magnetic disk device into a standby state.

If the power is turned off while the magnetic head 2 is on the magnetic disk 1, the magnetic head 2 cannot ride on the flexure holding member 8 and remains in contact with the magnetic disk 1. When the power is turned on again, the sensor 16 does not generate voltage because the magnetic head 2 is not in the standby position, and the load/unload detection circuit 17 notifies the controller 11 that the magnetic head 2 is not in the separated state. . In order to rotate the magnetic disk 1, the controller 11 first instructs the spindle torque switching circuit 14 to switch the switch 18. As a result, the spindle torque switching circuit 14 sets the switch 18 to the R2 side. Next, a start command is sent to the spindle drive circuit 10 through the spindle start/stop signal line 12. The spindle drive circuit 10 rotates the magnetic disk 1 by causing a drive current 13 to flow through the spindle motor in response to a startup command. This drive current 13 is converted into a voltage by a resistor R2 in the spindle torque switching circuit 14 and fed back to the amplifier 20. This resistance R2 is the resistance R1
Since the resistance value is smaller, the drive current 13 is
It can be set so that more current flows than the normal starting current. Therefore, even when the magnetic head 2 and the magnetic disk 1 are in contact and the load on the spindle motor is heavy, a large amount of drive current 13 flows and the spindle motor rotates.

As described above, according to this embodiment, when the magnetic disk device starts the spindle motor from the standby state, the starting current can be set to be reduced, so that power saving can be achieved.

[0020]

As described above, according to the present invention, the starting current can be set to be reduced by providing the head separation detection means and the spindle torque switching means, thereby making it possible to save power.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the configuration of a magnetic disk device in an embodiment of the present invention.

[Figure 2] Plan view of a conventional magnetic disk device

[Figure 3] Configuration block diagram of a conventional magnetic disk device

[Explanation of symbols]

1 Magnetic disk 2 Magnetic head 3 Flexure 9 Spindle motor 11 Controller 16 Sensor 17 Load/unload detection circuit 19 Spindle control circuit

Claims (1)

[Claims] 1. A magnetic disk, a magnetic head for recording or reproducing information on the magnetic disk, a spindle motor for rotating the magnetic disk, a spindle driving means for driving the spindle motor, and a magnetic head for supporting the magnetic head. a head support, a head moving means for moving the magnetic head in the radial direction of the magnetic disk, and a head support holding member for holding the head support and keeping the magnetic head separated from the surface of the magnetic disk. a head separation detecting means for detecting that the magnetic head is separated from the magnetic disk surface by the head support holding member; and switching the starting torque of the spindle motor depending on whether the magnetic head is separated. A magnetic disk device equipped with spindle torque switching means.