JPH0991840A - Hard disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lower noise by using a power source of a smaller capacity. SOLUTION: Motor switches 2a to 2c are disposed between the power source 4 and disk-driving motors 1a to 1c of hard disk driving devices 3a to 3c. A start control means 7 is connected to these motor switches 2a to 2c and a start command means 6 is connected to this start control means 7. This start control means 7 first turns on the motor switch 2a when it is commanded by the start command means 6 to start. The motor switch 2b is turned on after the lapse of starting time (t) required for starting of the disk-driving motors 1a to 1c from the point of this time and the motor switch 2c is turned on after the lapse of starting time (t) from the point of this time. The starting time (t) is set so as to be slightly longer than the time until the driving currents of the disk-driving motors 1a to 1c attain stationary current after the turning on of the motor switches 2a, 2b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hard disk device having a plurality of hard disk drive devices.

[0002]

2. Description of the Related Art FIG. 5 is a block diagram showing a part of a conventional hard disk device. As shown in the figure, motor switches 2a to 2c are provided between the power source 4 and the disk drive motors 1a to 1c, and the disk drive motors 1a to 1c are provided.
c and the motor switches 2a to 2c form hard disk drive devices 3a to 3c. Further, a start command means 5 for controlling the motor switches 2a to 2c is provided.

In this hard disk device, when the start command is issued by the start command means 5, the motor switch 2
a to 2c are turned on, the power source 4 and the disk drive motors 1a to 1c are connected, and the disk drive motors 1a to 1c are connected.
1c rotates.

[0004]

However, in such a hard disk drive, the disk drive motor 1 is used.
a to 1c start rotating at the same time. When the drive current at the time of starting the disk drive motors 1a to 1c changes as shown by the broken line in FIG. 6, the current of the power supply 4 at start changes as shown by the solid line in FIG. Since the maximum current of the power supply 4 is three times the maximum drive current of the disk drive motors 1a to 1c at startup, the maximum current of the power supply 4 at startup becomes very large. Therefore, it is necessary to use a power source 4 having a large capacity. Moreover, since the disk drive motors 1a to 1c are simultaneously activated at the start of activation, noise is increased.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a hard disk device that can use a power source having a small capacity and can reduce noise.

[0006]

In order to achieve this object, according to the present invention, in a hard disk drive having first and second hard disk drives, a disk drive motor of the first hard disk drive is driven. There is provided start-up control means for starting the disk drive motor of the second hard disk drive after the current becomes a steady current.

[0007]

1 is a block diagram showing a part of a hard disk device according to the present invention. As shown in the figure, the start control means 7 including a microcomputer is connected to the motor switches 2a to 2c.
When the start instruction means 6 is connected to the start instruction means 6, and the start instruction means 6 issues a start instruction, the start control means 7 first turns on the motor switch 2a, and from that point on, the start time required for starting the disk drive motors 1a, 1b. The motor switch 2b is turned on after t has elapsed, and the motor switch 2c is turned on after the activation time t has elapsed from that point.
Here, the starting time t is set to be slightly longer than the time from when the motor switches 2a and 2b are turned on until the drive current of the disk drive motors 1a and 1b becomes a steady current.

In this hard disk device, after the drive current of the disk drive motor 1a becomes a steady current, the disk drive motor 1b is started and the drive current of the drive disk drive motor 1b becomes a steady current. Since the disk drive motor 1c is driven by the
2, the maximum current of the power supply 4 at the time of startup is smaller than three times the maximum drive current of the disk drive motors 1a to 1c. The current is small. Therefore, since the power source 4 having a small capacity can be used, the cost of the power source 4 becomes low and the power source 4 becomes small. Moreover,
Since the disk drive motors 1a to 1c are sequentially activated at the start of activation, noise at the time of activation is dispersed, so that noise can be reduced.

FIG. 3 is a block diagram showing a part of another hard disk device according to the present invention. As shown in the figure,
The start-up control means 9 including a microcomputer or the like is connected to the motor switches 2a to 2c in a so-called mochi system (daisy chain), that is, one flat cable in order, and the start-up command means 8 is connected to the start-up control means 9 to start-up command. When the activation is instructed by the means 8, the activation control means 9 turns on the motor switch 2a at the same time when the activation is instructed, and turns on the motor switch 2b after the activation time t has elapsed from the time when the activation was instructed. ,
Further, the motor switch 2c is turned on after a time twice as long as the start time t has elapsed from the time when the start command was issued.

Also in this hard disk device, the maximum current of the power source 4 at the time of startup is the disk drive motors 1a-1.
Since it is smaller than three times the maximum drive current of c, a power source 4 having a small capacity can be used, and noise at the time of startup is dispersed, so that noise reduction can be achieved.

Note that this embodiment is based on SASI (Shugate Associate System Interfa).
ce), S.S.S.I (SCSi; Small Comp)
computer system interface). FIG. 4 is a block diagram showing a part of another hard disk device according to the present invention. As shown in the figure, the motor switches 2a-2c have timers 10a-1
0c is provided, the timers 10a to 10c are connected to the start command means 11, and when the start command means 11 issues a start command, the timer 10a turns on the motor switch 2a at the same time as the start command is issued, and the timer 10b is also activated. Indicates that the motor switch 2b is turned on after the start time t has passed from the time when the start command is issued, and the timer 10c turns on the motor switch 2c after the time twice the start time t has elapsed from the time when the start command is issued. And timer 10a ~
Reference numeral 10c constitutes a start control means.

Also in this hard disk device, the maximum current of the power source 4 at the time of startup is the disk drive motors 1a-1.
Since it is smaller than 3 times the maximum drive current of c, a power source 4 having a small capacity can be used, and noise is dispersed, so that noise reduction can be achieved.

In the hard disk device shown in FIG. 4, the start time t and the device number N of the hard disk drive devices 3a to 3c can be set in the timers 10a to 10c, and the timer set time T = tN in the timers 10a to 10c. The calculation may be performed so that when the activation instruction means 11 issues an activation instruction, the timers 10a to 10c turn on the motor switches 2a to 2c after the timer set time T has elapsed. In this case, for example, if the device numbers N of the hard disk drive devices 3a to 3c are 0, 1 and 2, respectively, the timer set times T of the timers 10a to 10c are 0, t and 2t, respectively, and the timer 10a is instructed to start. At the same time, the motor switch 2a is turned on, and the timer 10b turns on the motor switch 2b after the activation time t elapses from the time when the activation is commanded.
0c turns on the motor switch 2c after a time that is twice as long as the start time t from the time when the start is instructed. Then, by doing this, by changing the setting of the device number N, the starting order of the disk drive motors 1a to 1c can be changed.

In the above-described embodiment, the case of having three hard disk drive devices 3a to 3c has been described, but the present invention can be applied to the case of having a plurality of hard disk drive devices. Further, in the above-described embodiment, the motor switches 2a to 2c are provided in all the hard disk drive devices 3a to 3c,
Without providing a motor switch in one of the hard disk drive devices, the disk drive motor of the hard disk drive device is started at the same time when the power is turned on, and the other hard disk drive devices are provided with motor switches to start the order. According to the above, the motor switch may be turned on after the current of the disk drive motor started before becomes a steady current.

[0015]

As described above, in the hard disk drive according to the present invention, since the maximum current of the power supply at the time of startup is smaller than the sum of the maximum drive currents of the first and second disk drive motors, Since the maximum current of the power supply at the time is small, a power supply having a small capacity can be used, and noise at the time of start-up is dispersed, so that the noise can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing a part of a hard disk device according to the present invention.

FIG. 2 is a graph showing a temporal change in a current of a power supply when the hard disk device shown in FIG. 1 is activated.

FIG. 3 is a block diagram showing a part of another hard disk device according to the present invention.

FIG. 4 is a block diagram showing a part of another hard disk device according to the present invention.

FIG. 5 is a block diagram showing a part of a conventional hard disk device.

6 is a graph showing a temporal change in a current of a power supply when the hard disk device shown in FIG. 5 is activated.

[Explanation of symbols]

 1a-1c ... Disk drive motors 2a-2c ... Motor switches 3a-3c ... Hard disk drive 4 ... Power supply 7 ... Startup control means 9 ... Startup control means 10a-10c ... Timer

Claims (1)

[Claims] 1. A hard disk device having first and second hard disk drive devices, wherein after the current of a disk drive motor of the first hard disk drive device becomes a steady current, the second hard disk drive device of the second hard disk drive device. A hard disk device comprising a start control means for starting a disk drive motor.