JP2001014789A - Disk storage device and spindle motor controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the time required until attaining the normal rotation and resultantly to improve the efficiency of the recording operation of data at the time of head loading operation, by suppressing the rotational fluctuation of a spindle motor due to the external disturbance. SOLUTION: In a disk drive utilizing the head load/unload system, a control gain of the feedback control system for the spindle motor 15 is set to a high level at the time of load control of the head 12, and the SPM control system to turn back the control gain to a normal gain after attaining the normal rotation is presented. By a CPU 20, the control gain is increased at the time of loading the head 12, and the responsiveness to the external disturbance is improved to suppress the rotational fluctuation. When the rotational fluctuation is suppressed to be within the allowable range, the control gain is turned back to the normal gain by the CPU 20 for maintaining the stability of the feedback control system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spindle motor control applied to a head load / unload type disk drive, and more particularly to a function of suppressing a disk rotation fluctuation caused by an air frictional force generated between a head and a disk. The present invention relates to a disk storage device and a spindle motor control device.

[0002]

2. Description of the Related Art In recent years, hard disk drives (HD)
In the field of D), a head-load / unload-type (or ramp-load-type) head moving mechanism attracts attention. The head moving mechanism moves the head between the disk and a head retracting member called a ramp disposed outside the disk without the head and the disk surface contacting each other.

In the HDD, when power is turned on, a spindle motor is started to rotate a disk. At the time of this startup, the head is held by the lamp and retracted from the disk. Here, the head means, in a narrow sense, a read / write element mounted on the slider, but here means a head including the slider. The head moving mechanism generally includes an actuator including a voice coil motor (VCM) and a suspension for holding the head. The suspension is provided with a rod-shaped member called a tab. Since the tab is supported by the ramp, the head is retracted by the ramp as a result.

In the data recording / reproducing operation, the head is moved from the position of the ramp onto the rotating disk by the drive control of the actuator (load operation). Conversely, when the data recording / reproducing operation is completed, the head is moved from the top of the disk to the ramp, and enters a retracted state (unload operation).

[0005]

In an HDD employing a head loading / unloading type head moving mechanism, the head moves from a ramp and is loaded onto a disk when recording or reproducing data. At this time, the disk is being rotated by the spindle motor. In the HDD, a minute gap is maintained between the head and the disk surface due to the air pressure accompanying the rotational movement of the disk (air bearing mechanism). In other words, the head is flying at a predetermined distance (flying height) from the disk surface.

[0006] With such an air bearing mechanism, when the head is loaded on the disk, rapid air friction occurs between the head and the disk surface. This air friction is applied as a disturbance to a feedback control system (sometimes abbreviated as an SPM control system) of a spindle motor (SPM), and causes a rotation fluctuation of the disk. The SPM control system roughly includes an SPM driver and a CPU (a microcontroller constituting a main control device of the HDD).

[0007] The SPM control system executes feedback control so that the SPM becomes a steady rotation speed. However, since the rotation fluctuates due to the influence of the disturbance, it takes a long time for the SPM rotation speed to reach the target speed. Cost.
It has been measured that when the head is loaded, a rotational fluctuation rate of about 0.1% at maximum (the allowable range is about 0.05%) occurs in the SPM. When a write command (data write command) is issued from the host system (such as a personal computer) during the rotation fluctuation of the SPM, the CPU
Has a function of judging that if data is written when the rotation fluctuation is large, the data write frequency is shifted, and prohibits the write operation. Therefore, when the rotation fluctuation period of the SPM is long, the prohibition time of the write operation becomes long.
For this reason, in particular, the efficiency of the data recording operation decreases.

Accordingly, an object of the present invention is to reduce the time required to reach steady rotation by suppressing fluctuations in the rotation of the spindle motor due to disturbance during the loading operation of the head, and as a result, the efficiency of the data recording operation is reduced. Is to improve.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a disk drive having a head loading / unloading type head moving mechanism, which reduces the air friction generated between the head and the disk when the head is loaded on the disk. The present invention relates to an SPM control unit that suppresses rotation fluctuation acting on an SPM control system due to accompanying disturbance.

[0010] The SPM control means comprises a feedback control system for controlling a spindle motor for rotating the disk to rotate steadily based on a target rotation speed. The present invention includes means for confirming (detecting) that the head has loaded onto the disk from the ramp, setting the control gain to a high level from the time of the loading until the steady rotation, and after reaching the steady rotation. It has a function to return the control gain to the normal gain. In short, the SPM control means of the present invention has a function of changing the control gain, and increases the control gain when the head is loaded, improves the responsiveness to disturbance, and suppresses the rotation fluctuation. Further, if the control gain is increased, the stability of the feedback control system may be degraded and an oscillation phenomenon may be caused. Therefore, when the rotational fluctuation is suppressed to within an allowable range, the gain is returned to the normal gain.

According to the configuration of the present invention, when recording and reproducing data, when the head is loaded on the disk, the rotation fluctuation of the SPM due to disturbance caused by the air frictional force generated between the head and the disk is reduced. It is possible to reduce the time. Therefore, when loading the head, SP
Since M can reach a steady rotation, the write operation prohibition period can be shortened as a result.

[0012]

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

(Configuration of Disk Drive) FIG. 1 is a block diagram showing a main part of an HDD relating to each embodiment.

As shown in FIG. 1, the HDD includes a disk 10 as a data recording medium, and a head (slider and read / write element) for reading / writing data.
12 and an actuator 1 supporting the head 12
3 Here, for convenience, it is assumed that the number of disks 10 is one and that the head 12 is arranged only on one side of the disk 10.

A large number of concentric tracks are formed on each surface of the disk 10, and a plurality of servo areas on which servo data used for controlling the positioning of the head 12 are recorded are arranged at equal intervals on each track. ing. These servo areas are radially arranged on the disk 10 from the center over each track. A data area (user area) is provided between the servo areas, and a plurality of data sectors are set in the data area. The servo data includes a cylinder code indicating a cylinder number of a cylinder in which a corresponding servo area exists, and burst data for indicating a position error in the cylinder indicated by the cylinder code by a waveform amplitude. A sector pulse is generated from the servo data read by the head 12. As will be described later, the CPU 20 controls the head 12 by the sector pulse.
Is loaded onto the disk 10 (sector detection processing).

The head 12 is a rotary type actuator 1
3 is attached. The actuator 13 has a suspension for supporting the head 12, and drives the disk 1 by a driving force of a voice coil motor (VCM) 11.
Rotate in the radial direction above zero. This actuator 1
By the drive control of 3, the head 12 is positioned on the target track on the disk 10.

A ramp 14 for retracting the head 12 (retract) is arranged on the outer peripheral side of the disk 10. As shown in FIG.
0 is a member for holding the head 12 unloaded from above. Specifically, the lamp 14 is
Has a slant portion 141 for supporting a tab 132 attached to the suspension 131 of FIG. The head 12 is in the retracted state (parking) by the movement of the tab 132 to the concave portion (parking area) of the ramp 14 (see 30A in FIG. 3).

The disk 10 has a spindle motor (SP)
M) 15 to rotate at high speed. SPM15 is SP
It is driven by a drive current supplied from the M driver 21 (details will be described later with reference to FIG. 5). VCM1
1 is driven by a drive current supplied from the VCM driver 22. The SPM driver 21 and the VCM driver 22 are integrated as a one-chip driver IC 23. SPM driver 21 related to the same embodiment
Constitutes a feedback control system together with the CPU 20.

After the head 12 is positioned on the target track of the disk 10 by the actuator 13,
Data read / write is executed for an access target data sector included in the target track. The head 12 is connected to a head amplifier IC 16 mounted on an FPC. The head amplifier IC 16 has a read / write amplifier. The read amplifier amplifies a read signal from the head 12 and sends the amplified signal to the read / write channel 17. The head amplifier IC 16 converts write data output from the read / write channel 17 into a write current by a write amplifier and sends the write current to the head 12.

The read / write channel 17 has an automatic gain control (AGC) amplifier for maintaining a read signal sent from the head amplifier IC 16 at a constant level, and reproduces the read signal into, for example, NRZ code data. , An encoding circuit for generating write data to be recorded on the disk 10, a servo circuit for extracting servo data from a read signal, and the like. Read / write channel 1
Numeral 7 outputs servo data to the CPU 20 and exchanges read / write data with the disk controller (HDC) 18.

The CPU 20 is a microprocessor constituting a main controller (also called a microcontroller) for performing various controls of the disk drive according to a control program stored in a memory (not shown).
The CPU 20 performs drive control of the SPM 15 and servo control (head positioning control) related to the embodiment. Further, the CPU 20 executes a loading operation and an unloading operation of the head 12. That is, the CPU 20
When the SPM 15 is activated to start the read / write operation (data recording / reproducing operation), the head 12
A load operation for moving the disk from No. 4 onto the disk 10 is executed (load control). Further, when the end of the read / write operation or the stop instruction of the SPM 15 (including the power-off) is given from the host system, the CPU 22 operates the head 1.
An unload operation for moving the disk 2 from the disk 10 to the ramp 14 is executed (unload control).

(Load operation and rotation fluctuation of SPM)
3 and 4, the loading operation of the head 12 and the SP
The relationship between M15 and the rotation fluctuation will be specifically described.

FIG. 3 shows a locus of movement when the head 12 retracted to the ramp 14 loads onto the rotating disk 10. That is, the head 12 (actually, the tab 132) slides from the position (30A) of the parking area (recess) of the ramp 14 to the position (30B) of the flat surface and the position (30C) of the inclined surface. And disk 1
Load to the position above 0 (30D).

In such a loading operation, the head 1
No. 2 is affected by air friction caused by air pressure generated between the disk 10 and the rotating disk 10 from near the position (30C). Then, when the head 12 moves on the disk 10 (at the position 30D), by the action of the air frictional force,
The rotation fluctuation occurs in the SPM 15 for rotating the disk 10.

FIG. 4 shows the relationship between the rotational fluctuation rate of the SPM 15 and the passage of time during the load / unload operation. After the SPM 15 is activated and the rotational movement of the disk 10 is started, in the area where the head 12 is located on the ramp 14 (ramp area), there is no influence of air friction, so that the rotational fluctuation rate of the SPM 15 is almost zero. It is. When the head 12 moves from the ramp 14 onto the disk 10 (disk area), S
The rotation fluctuation rate of the PM 15 shows a characteristic as shown by a curve 401. That is, it is actually measured that a rotation fluctuation of about 0.1% occurs at the maximum in the SPM 15 during the loading operation. Normally, in the HDD, the allowable range of the rotation fluctuation rate at which the write operation for recording data on the disk 10 is permitted is about ± 0.05%.

Therefore, as shown in FIG. 4, a certain time ΔT is required from the time when the head 12 is loaded to the time when the write operation converges to the permitted rotation fluctuation rate (± 0.05%). become. In other words, the head 12
Means that the write operation is prohibited until the time ΔT elapses after the data is loaded. Therefore, the present invention reduces the SPM 15 so that the time ΔT from the loading of the head 12 to the convergence to the rotation variation rate (approximately ± 0.05%) at which the write operation is permitted is reduced to the time ΔTa.
(See curve 400). Note that even during the unloading operation, as shown by the curve 402 in FIG. 4, the rotation fluctuation occurs in the SPM 15.

(Feedback Control System for SPM Control) The configuration of the SPM driver 21 related to the first embodiment of the present invention and a feedback control system for SPM control will be described below with reference to FIG.

The SPM 15 has a CPU as shown in FIG.
The drive is controlled by a feedback control system including the SPM driver 20 and the SPM driver 21. In FIG. 5, the plant 50 to be controlled means the SPM 15. This system includes a gain setting section 51, a stabilization compensation section 5
2, each element of a subtraction unit 53 and a target speed setting unit 54.

In this embodiment, the CPU 20 sets (changes) the control gain in the gain setting section 51 and sets the target rotation speed in the target speed setting section 54. Here, when the control gain is “G”, the target rotation speed value is “TV”, and the compensation coefficient of the stabilization compensation unit 52 is “Cs”, the characteristic “P” of the plant (SPM) 50 is as follows. It is expressed by equation (1).

P = Kt / (JCs + Kd) (1) where "Kt" means the motor torque of the SPM 15, "J" means inertia,
“Kd” means damping.

In such a system, as described above, the rotation fluctuation due to the air friction between the head 12 and the disk 10 corresponds to the disturbance (D) added to the input of the plant 50. Here, assuming that the rotation speed of the SPM 15 when the drive of the plant 50 is controlled is “RV”,
The error “E” from the target speed value “TV” calculated by the subtraction unit 53 is expressed by the following equation (2).

E = TV−RV (2) From the above equations (1) and (2), the rotation speed “RV” is expressed by the following equation (3).

RV = (ECsG + D) P (3) Here, from the equations (2) and (3), the error “E” is expressed by the following equation (4).

E = (1 / (1 + CsGP)) TV + (P / (1 + CsGP)) D (4) As is apparent from the equation (4), when the value of the control gain “G” is increased, the equation Since the coefficient “P / (1 + CsGP)” of “D” in the second term on the right side is small, the effect of disturbance “D” can be suppressed as a result. On the other hand, however, when the value of the control gain “G” is increased, the stability of the feedback control system is degraded, and the possibility of causing an oscillation phenomenon is increased.

Therefore, the system according to the embodiment sets a control gain (G1) with good stability during normal rotation control (steady rotation control), and sets the control gain (G1) during load when disturbance (D) occurs. , A control gain with good response (G2> G1) is set. Hereinafter, the control operation of the system will be described with reference to the flowcharts of FIGS. 6, 7, and 8.

First, the control operation at the time of starting the SPM 15 is as follows.
This is executed by a control routine as shown in FIG. That is, the CPU 20 sets a relatively low level gain (G1) as the control gain (step S1). At the same time, a target rotation speed value (TV) is also set.

The SPM driver 21 executes startup control so that the error (E) between the target rotation speed value (TV) set by the CPU 20 and the rotation speed (RV) of the SPM 15 falls within an allowable range (step S2). , S4, S
5). The CPU 20 monitors the rotation speed of the SPM 15 based on the interval of the rotation speed detection pulse generated from the SPM 15 (step S3). The interval between the rotation speed detection pulses is detected by a logic control circuit constituted by a gate array 19, as shown in FIG.

The CPU 20 determines the rotational speed of the SPM 15 (R
If the error (E) with respect to V) is within a specified range of, for example, “± 0.3%”, the motor ready flag (motor)
ready flag) (step S)
6). If it is out of the specified range, retry of the start control is executed (NO in step S5).

Next, the control operation at the time of the load operation is executed by a control routine as shown in FIG. First, CP
U20 checks whether or not the motor ready flag is set, and determines whether or not the activation process of the SPM 15 has been completed (steps S10 and S11). If the motor ready flag is not set, the disk 10 is not rotating, so that the loading operation cannot be executed. Normally, the CPU 20 executes load control according to a command from the host system. At this time, if the SPM 15 has not been started up normally, predetermined error processing is executed (NO in step S11).

When the SPM 15 starts normally and the disk 1
If 0 is performing a steady rotation motion, the CPU 20 executes load control by timer interrupt processing (step S12). As a result, as described above, the actuator 13 is driven, the head 12 moves from the ramp 14, and a loading operation for loading onto the disk 10 is performed. The CPU 20 monitors whether the head 12 has been loaded on the disk 10 by detecting the sector pulse from the gate array 19 (step S13). Here, if the head 12 is not loaded on the disk 10 even after the specified time has elapsed from the start of the load control, C
The PU 20 determines that a failure has occurred and shifts to predetermined error processing (YES in step S15).

On the other hand, when the CPU 20 confirms that the head 12 has been loaded onto the disk 10 by the load control, the CPU 20 sets a relatively high level gain (G
2) and end the load control (step S1).
4).

Next, the steady rotation control operation of the SPM 15 is as follows.
This is executed by a control routine as shown in FIG. That is, as described above, the CPU 20
The rotation speed of the SPM 15 is detected based on the rotation speed detection signal from the CPU, and a comparison process with the set target rotation speed is executed (steps S20 and S21). If an error (E) between the target rotation speed (TV) and the rotation speed (RV) of the SPM 15 is out of a specified range of, for example, about “± 0.05%”, the CPU 20 sets a write operation prohibition flag. (NO in step S22, S25). That is, at this point, S
Even if a high-level gain (G2) is set in the PM feedback control system, the CPU 20 prohibits the write operation because the rotation fluctuation exceeding the allowable range occurs in the SPM 15.

On the other hand, the CPU 20 sets the target rotation speed (T
V) and the error (E) between the rotation speed (RV) of the SPM 15
Is within a specified range of, for example, about “± 0.05%”, the control gain of the SPM feedback control system is set from a high-level gain (G2) to a normal low-level gain (G1) (step). YES at S22, S
23). That is, the CPU 20 determines that the rotation fluctuation of the SPM 15 has been suppressed to within the allowable range, and shifts to the normal rotation control using the normal control gain (G1) (step S24).

As described above, according to the present embodiment, when the head 12 is loaded on the disk 10 by the load control, the control gain of the SPM feedback control system is changed from the normal low level gain (G1). To the high level gain (G2). This allows the system to control the control gain “G” based on the principle described above.
Is increased, the responsiveness to the disturbance “D” is improved, and as a result, the rotation fluctuation of the SPM 15 is suppressed in a short time (for example, see the curve 400 in FIG. 4). On the other hand, if the value of the control gain “G” is kept large, the stability of the feedback control system is degraded. Therefore, after suppressing the rotation fluctuation, the normal low-level gain (G
Returning to 1), the process proceeds to the steady rotation control of the SPM 15.

(Modification of the Same Embodiment) FIGS. 9 and 10
9 is a flowchart showing a modification of the first embodiment. In this modification, when the control gain is changed to a high-level gain (G2) during the load control and the rotation control of the SPM 15 is executed, if the control gain exceeds a predetermined time, the control gain is changed to a higher level. A control operation for returning to the normal low level gain (G1) is included. Hereinafter, FIGS. 9 and 10
This will be specifically described with reference to FIG.

First, the control operation at the time of starting the SPM 15 is as follows.
This is the same as the control routine shown in FIG. That is, C
The PU 20 sets a relatively low level gain (G1) as the control gain, and sets the target rotation speed value (TV) and the SPM
The error (E) from the rotation speed (RV) is, for example, “±
If it is within the specified range of about 0.3%, the motor ready flag is set. If the value is out of the specified range, retry of the start control is executed.

Next, the control operation at the time of the load operation is executed by a control routine as shown in FIG. First, CP
U20 initializes an internal timer for timekeeping operation for determining the change timing of the set gain (step S3).
0). Further, the CPU 20 checks whether or not the motor ready flag is set, and determines whether or not the activation process of the SPM 15 has been completed (steps S31 and S31).
32). If the motor ready flag is not set, the SPM 15 has not been started up normally, and a predetermined error process is executed (NO in step S32).

When the SPM 15 starts normally and the disk 1
If 0 is performing a steady rotation motion, the CPU 20 executes the above-described load control (step S33). CPU2
0 monitors whether or not the head 12 has been loaded onto the disk 10 by detecting a sector pulse from the gate array 19 (step S34). Here, if the head 12 is not loaded onto the disk 10 even after the specified time has elapsed from the start of the load control, the CPU 20 determines that a failure has occurred and shifts to a predetermined error process (YES in step S37). .

On the other hand, when the CPU 20 confirms that the head 12 has been loaded onto the disk 10 by the load control, the CPU 20 sets a relatively high level gain (G
Change to 2) and activate the internal timer to end the load control (steps S35, S36). That is, CPU2
0 shifts to the rotation fluctuation suppression mode in which a high-level gain (G2) is used at the time of loading as described above.
At this time, in this modified example, the timing at which the control gain is returned from the high-level gain (G2) to the normal gain (G1) is determined by monitoring the elapse of the specified time by the internal timer (see FIG. 10). .

Next, the steady rotation control operation of the SPM 15 is as follows.
This is executed by a control routine as shown in FIG. That is, as described above, the CPU 20
The rotation speed of the SPM 15 is detected based on the rotation speed detection signal from the CPU, and comparison processing with the set target rotation speed is executed (steps S40 and S44). Here, this modified example
The CPU 20 checks the elapsed time by the internal timer,
It is determined whether or not a preset specified time has elapsed (steps S41 and S42).

The CPU 20 sets the control gain to a high level gain (G2) based on the result of counting by the internal timer, and resets the gain to a normal gain (G1) when a predetermined time has elapsed. (Step S43). Also,
If the time has passed within the specified time, the high-level gain (G2) is maintained (YES in step S42). CP
U20 indicates that the error (E) between the target rotation speed (TV) and the rotation speed (RV) of the SPM 15 is, for example, “± 0.05%”.
If it is out of the specified range, the write operation prohibition flag is set (NO in step S45, S47). That is,
At this point, the CPU 20 prohibits the write operation because the rotation fluctuation exceeding the allowable range has occurred in the SPM 15.

On the other hand, the CPU 20 sets the target rotation speed (T
V) and the error (E) between the rotation speed (RV) of the SPM 15
However, if it is within a specified range of, for example, about “± 0.05%”, it is determined that the rotation fluctuation of the SPM 15 has been suppressed to within an allowable range, and the routine shifts to the normal rotation control using the normal control gain (G1). (Step S46).

As described above, according to this modification, the control gain of the SPM feedback control system is changed from a normal low level gain (G1) to a relatively high level gain (G2) during load control. , The rotation fluctuation of the SPM 15 is suppressed for a short time. Furthermore, a high level of gain (G
When the specified time has elapsed since the setting of 2), the gain is reset to the normal low level gain (G1). Thus, by maintaining a high level of gain (G2),
The time during which the feedback control system is in an unstable state is limited, and it is possible to return to the normal low-level gain (G1) in the shortest possible time and shift to the steady rotation control of the SPM 15.

(Second Embodiment) FIGS. 11 to 13 are diagrams related to a second embodiment of the present invention. In the present embodiment, the fact that the head 12 has moved onto the disk 10 during the load control is determined by the speed (V
This is a system for detecting based on the CM control current value).
Hereinafter, the principle of the load detection operation will be described with reference to FIG.

In the loading operation, the head 12 moves as shown in FIG.
As shown in (B), from the parking area (area 1) of the ramp 14, through areas 2 and 3, the disk 10
Move to area 4 above. In such a locus of movement, when moving in area 1 of ramp 14, since the uphill of ramp 14 is climbed, the VCM control current value supplied from VCM driver 22 increases as shown in FIG. It shows a tendency (see characteristic curve 111). Therefore, the speed of the VCM 11 is in the acceleration mode (characteristic curve 1).
10). When the head 12 moves to the area 2, V
The CM control current value becomes substantially constant, and the speed of the head 12 by the VCM 11 also changes to a constant speed. Furthermore, head 1
When the vehicle 2 descends the area 3 which is an inclined surface, the speed of the head 12 by the VCM 11 relatively increases and the VCM 11
The control current value decreases. Then, when the head 12 moves to the area 4 on the disk 10, the friction with the ramp 14 disappears, so that the VCM control current value decreases to almost zero, and the speed of the head 12 by the VCM 11 reaches the target speed. . Therefore, the CPU 20 starts the VCM control current value (VCM including the CPU 20) from the start of the load operation.
By monitoring the output control value of the feedback control system), it can be detected that the head 12 has moved to the area 4 on the disk 10.

The control operation of the SPM feedback control system utilizing such a principle will be described with reference to the flowcharts of FIGS.

First, the control operation at the time of starting the SPM 15 is as follows.
This is the same as the control routine shown in FIG. That is, C
The PU 20 sets a relatively low level gain (G1) as the control gain, and sets the target rotation speed value (TV) and the SPM
The error (E) from the rotation speed (RV) is, for example, “±
If it is within the specified range of about 0.3%, the motor ready flag is set. If the value is out of the specified range, retry of the start control is executed.

Next, the control operation at the time of the load operation is shown in FIG.
This is executed by a control routine as shown in FIG. First, C
The PU 20 checks whether or not the motor ready flag is set, and determines whether or not the activation process of the SPM 15 has been completed (Steps S50 and S51). If the motor ready flag is not set, the SPM
15 has not been started up normally, a predetermined error process is performed (NO in step S51).

When the SPM 15 starts normally and the disk 1
If 0 indicates a steady rotation motion, the CPU 20 executes the above-described load control (step S52). here,
The CPU 20 compares the speed of the head 12 by the VCM 11 required for the load operation with the target head speed, and determines whether or not the error has converged within a specified error range (steps S53 and S54). When the speed of the head 12 by the VCM 11 substantially matches the target speed, the CPU 20 checks the VCM control current value and determines whether or not the current value is within a specified value range (step S5).
5, S56). That is, as described above, the CPU 20
The head 12 is placed on the disk 10 by the load control (FIG. 11).
It is determined whether or not the vehicle has moved to the area 4) shown in FIG. If neither the head speed nor the VCM control current value is outside the specified range, the CPU 20 determines that the head 12 has not moved on the disk 10 (NO in step S54, NO in S56). In this case, the CPU 20
A counter (count value MC) described later is cleared, and it is determined whether a specified time has elapsed from the start of the load control (steps S58 and S59). If the head 12 is not loaded onto the disk 10 even after the specified time has elapsed, the CPU 20 determines that a failure has occurred and shifts to a predetermined error process (YES in step S59).

On the other hand, when the CPU 20 confirms that the head 12 has been loaded onto the disk 10 by the load control, the CPU 20 checks the count value MC of the counter to determine whether or not the count has reached a predetermined number of times. (Steps S57 and S60). If the specified number of times has not been reached, the count value MC is incremented and the load control is continued (YES in step S60, S6).
1).

If the number of checks of the VCM control current value within the specified range matches the specified number of times,
The load control is terminated, and a relatively high level gain (G
Change to 2) (NO in step S60, S62). That is, as described above, the CPU 20 shifts to the rotation fluctuation suppression mode using a high-level gain (G2) at the time of loading.

Next, the steady rotation control operation of the SPM 15 is as follows.
This is executed by a control routine as shown in FIG. That is, as described above, the CPU 20
The rotation speed of the SPM 15 is detected based on the rotation speed detection signal from the CPU, and comparison processing with the set target rotation speed is executed (steps S70 and S71). If an error (E) between the target rotation speed (TV) and the rotation speed (RV) of the SPM 15 is out of a specified range of, for example, about “± 0.05%”, the CPU 20 sets a write operation prohibition flag. (NO in step S72, S75). That is, at this point, S
Even if a high-level gain (G2) is set in the PM feedback control system, the CPU 20 prohibits the write operation because the rotation fluctuation exceeding the allowable range occurs in the SPM 15.

On the other hand, the CPU 20 sets the target rotation speed (T
V) and the error (E) between the rotation speed (RV) of the SPM 15
Is within a specified range of, for example, about “± 0.05%”, the control gain of the SPM feedback control system is set from a high-level gain (G2) to a normal low-level gain (G1) (step). YES at S72, S
73). That is, the CPU 20 determines that the rotation fluctuation of the SPM 15 has been suppressed to within the allowable range, and shifts to the normal rotation control using the normal control gain (G1) (step S74).

As described above, also in this embodiment, as in the first embodiment, the head 1 is controlled by the load control.
2 is loaded onto the disk 10, the control gain of the SPM feedback control system is changed from a normal low level gain (G1) to a relatively high level gain (G1).
Change to 2). Accordingly, the system improves the response to the disturbance “D” by increasing the value of the control gain “G” based on the principle described above,
As a result, rotation fluctuation of the SPM 15 is suppressed in a short time. On the other hand, if the value of the control gain “G” is kept large, the stability of the feedback control system is degraded. Therefore, after suppressing the rotation fluctuation, the normal low-level gain (G
Returning to 1), the process proceeds to the steady rotation control of the SPM 15.

(Modification of Second Embodiment) FIGS. 14 and 15 are flowcharts showing a modification of the above-described second embodiment. This modification example is similar to the modification example of the above-described first embodiment, when the control gain is changed to the high-level gain (G2) during the load control and the rotation control of the SPM 15 is executed, If the specified time exceeds the specified time, the control gain is changed to a normal low level gain (G1).
Control operation. Hereinafter, a specific description will be given with reference to FIGS. 14 and 15.

First, the control operation at the time of starting the SPM 15 is as follows.
This is the same as the control routine shown in FIG. That is, C
The PU 20 sets a relatively low level gain (G1) as the control gain, and sets the target rotation speed value (TV) and the SPM
The error (E) from the rotation speed (RV) is, for example, “±
If it is within the specified range of about 0.3%, the motor ready flag is set. If the value is out of the specified range, retry of the start control is executed.

Next, the control operation at the time of the load operation is shown in FIG.
This is executed by a control routine as shown in FIG. First, C
The PU 20 initializes an internal timer for timekeeping operation for determining the timing for changing the set gain (step S20).
80). The subsequent processing is the same as the control routine shown in FIG. 12 described above, and steps S81 to S93 in FIG. 14 mean processing corresponding to steps S50 to S62 in FIG. And the CPU 20
Confirms that the head 12 has been loaded onto the disk 10 by the load control, changes the control gain to a relatively high level gain (G2), activates an internal timer, and ends the load control ( Step S93, S
94). That is, as described above, the CPU 20 shifts to the rotation fluctuation suppression mode using a high-level gain (G2) at the time of loading. At this time, in this modification, the control gain is changed from the high-level gain (G2) to the normal gain (G
Determine the timing to return to 1).

Next, the steady rotation control operation of the SPM 15 is as follows.
This is executed by a control routine as shown in FIG. This control routine is the same as the control routine shown in FIG. 13 described above, except for the process of checking the timer value (steps S101 and S102).

That is, as described above, the CPU 20 receives the SPM from the gate array 19 based on the rotation speed detection signal.
Then, the rotation speed detection unit 15 detects the rotation speed and performs comparison processing with the set target rotation speed (steps S100 and S103). Here, in the present modified example, the CPU 20 checks the elapse of time by the internal timer, and determines whether or not a preset specified time has elapsed (steps S101 and S102).
The CPU 20 sets the control gain to a high-level gain (G2) based on the result of counting by the internal timer, and then, when a predetermined time has elapsed, the normal gain (G1).
Is reset (step S106). If the time has elapsed within the specified time, the high-level gain (G2) is maintained (YES in step S102). The CPU 20
Target rotation speed (TV) and rotation speed (RV) of SPM15
If the error (E) is outside the specified range of, for example, about “± 0.05%”, a write operation prohibition flag is set (NO in step S104, S107). That is, at this point, the CPU 20 prohibits the write operation because the rotation fluctuation exceeds the allowable range in the SPM 15.

On the other hand, the CPU 20 sets the target rotation speed (T
V) and the error (E) between the rotation speed (RV) of the SPM 15
However, if it is within a specified range of, for example, about “± 0.05%”, it is determined that the rotation fluctuation of the SPM 15 has been suppressed to within an allowable range, and the routine shifts to the normal rotation control using the normal control gain (G1). (Step S105).

As described above, also in the case of this modification, similarly to the modification of the above-described first embodiment, when the head 12 is loaded on the disk 10 by the load control, the control gain of the SPM feedback control system is controlled. At the time of normal load control, the control gain of the SPM feedback control system is changed from a normal low level gain (G1) to a relatively high level gain (G2) to suppress the rotation fluctuation of the SPM 15 for a short time. . Further, when the specified time has elapsed since the gain was set to the high level (G2),
The gain is reset to the normal low level gain (G1). Thus, by maintaining the high level gain (G2), the time during which the feedback control system is in an unstable state is limited, and the normal low level gain (G1) is returned to the normal low level gain in a short time as possible. It is possible to shift to the steady rotation control.

(Third Embodiment) FIG. 16 shows an SPM driver 210 and a CPM driver according to a third embodiment of the present invention.
FIG. 2 is a block diagram showing an SPM feedback control system including a PU 20. SPM driver 21 of the present embodiment
0 is a gain setting section 51, a stabilization compensation section 52, a subtraction section 5
3. In addition to the target speed setting unit 54, each component of the disturbance correction unit 55 is provided. The disturbance correction unit 55 is ON / OFF controlled by the CPU 20 to provide a disturbance (D) corresponding to the rotation fluctuation due to the air friction between the head 12 and the disk 10.
Is an element for adding a correction value (F) for eliminating the error in feedforward.

In the system of the embodiment, the control gain is set to “G”, the target rotation speed value is set to “TV”, the compensation coefficient of the stabilization compensator 52 is set to “Cs”, and the plant (S
The characteristic of the PM) 50 is “P = Kt / (JCs + Kd)”. However, "Kt" means the motor torque of the SPM 15, "J" means inertia, and "Kd" means damping.

Also in such a system, assuming that the rotation speed of the SPM 15 when the drive of the plant 50 is controlled is “RV”, the error “E” from the target speed value “TV” calculated by the subtraction unit 53 is , And is represented by the following equation (5).

E = TV−RV (5) The rotation speed “RV” is represented by the following equation (6).

RV = (ECsG−F + D) P (6) Here, from the equations (5) and (6), the error “E” is expressed by the following equation (7).

E = (1 / (1 + CsGP)) TV + (P (D−F) / (1 + CsGP)) (7) As is apparent from the equation (7), the correction value (F) is calculated by feedforward. The addition makes it possible to eliminate the disturbance “D”.

Hereinafter, the control operation of the system will be described with reference to the flowcharts of FIGS. 17 and 18.

First, the control operation at the time of starting the SPM 15 is as follows.
This is the same as the control routine shown in FIG. That is, C
The PU 20 sets a relatively low level gain (G1) as the control gain, and sets the target rotation speed value (TV) and the SPM
The error (E) from the rotation speed (RV) is, for example, “±
If it is within the specified range of about 0.3%, the motor ready flag is set. If the value is out of the specified range, retry of the start control is executed.

Next, the control operation at the time of the load operation is shown in FIG.
This is executed by a control routine as shown in FIG. First, C
The PU 20 checks whether or not the motor ready flag is set, and determines whether or not the activation process of the SPM 15 has been completed (Steps S110 and S111).
If the motor ready flag is not set, the disk 10 is not rotating, so that the loading operation cannot be executed. Normally, the CPU 20 executes load control according to a command from the host system. At this time, if the SPM 15 has not started normally,
A predetermined error process is executed (N in step S111).
O).

When the SPM 15 starts normally and the disk 1
If 0 indicates a steady rotation motion, the CPU 20 executes the load control (step S112). This drives the actuator 13 as described above,
The head 12 moves from the ramp 14 and a loading operation for loading onto the disk 10 is performed. The CPU 20
By detecting the sector pulse from the gate array 19, it is monitored whether or not the head 12 is loaded on the disk 10 (step S113). Here, even if the specified time has elapsed from the start of the load control, the head 12 is not
If it is not loaded on the CPU 0, the CPU 20 determines that a failure has occurred and shifts to predetermined error processing (step S1).
15 YES). On the other hand, when the CPU 20 confirms that the head 12 has been loaded onto the disk 10 by the load control, the CPU 20 turns on the disturbance correction unit 55 and adds the disturbance correction value (F) by feed forward (step S1).
14).

Here, as shown in the flowchart of FIG. 18, the CPU 20 turns off the disturbance correction unit 55 during the unload control. That is, the CPU 20 executes unload control for retreating the head 12 located on the disk 10 to the ramp 14 by ending the data recording / reproducing operation (step S120). The CPU 20 determines whether the head 12 has been unloaded from the disk 10 by detecting the sector pulse from the gate array 19 (step S121).

If the sector cannot be detected, the CPU 20 determines that the head 12 has retreated from the disk 10 and has moved to the ramp 14 (N in step S121).
O). In response to this determination result, the CPU 20 turns off the disturbance correction unit 55 (NO in step S121, S12
3). Here, if the specified time has not elapsed since the start of the unload control, the CPU 20 continues the unload control (NO in step S122). When a specified time has elapsed from the start of the unload control, the CPU 20
Ends the unload control, and shifts to processing such as turning off the power (YES in step S122).

(Modification of Third Embodiment) FIG. 19 is a flowchart showing a control routine of load control for explaining a modification of the third embodiment. This modified example is different from the head 12 at the time of the load control related to the second embodiment described above.
Is a system to which a method of detecting that the disk has moved onto the disk 10 based on the speed (VCM current value) of the VCM 11 is applied.

First, the CPU 20 checks whether or not the motor ready flag has been set, and determines whether or not the startup processing of the SPM 15 has been completed (step S).
130, S131). If the motor ready flag is not set, the SPM 15 has not been started up normally, and a predetermined error process is executed (step S131).
NO).

When the SPM 15 starts normally and the disk 1
If 0 indicates a steady rotation motion, the CPU 20 executes the above-described load control (step S132). Here, the CPU 20 compares the speed of the VCM 11 required for the load operation with the target VCM speed, and determines whether or not the error has converged within a specified error range (steps S133 and S134). If the speed of the head by the VCM 11 substantially matches the target speed, the CPU 20
Checks the VCM control current value and determines whether or not it is within the range of the specified value (steps S135 and S13).
6). If neither the head speed nor the VCM control current value is outside the specified range, the CPU 20 determines that the head 12 has not moved on the disk 10 (step S13).
4; NO in S136). In this case, the CPU 2
If the value is 0, the counter (count value MC) is cleared, and it is determined whether a specified time has elapsed from the start of the load control (steps S138 and S139). If the head 12 is not loaded onto the disk 10 even after the specified time has elapsed, the CPU 20 determines that a failure has occurred and shifts to a predetermined error process (YES in step S139).

On the other hand, when the CPU 20 confirms that the head 12 has been loaded onto the disk 10 by the load control, the CPU 20 checks the count value MC of the counter to determine whether or not the count has reached a predetermined number of times. (Steps S137 and S140). If the count has not been reached, the count value MC is incremented,
Continue the load control (YES in step S140, S
141).

If the number of checks of the VCM control current value within the specified range matches the specified number of times,
The load control ends, and the disturbance correction unit 55 is turned on (NO in step S140, S142).

The start control operation of the SPM 15 is similar to the control routine shown in FIG. The unload control operation is the same as the control routine shown in FIG.

(Fourth Embodiment) FIG. 20 to FIG.
FIG. 14 is a diagram related to a fourth embodiment of the present invention. This embodiment is a method in which the CPU 20 changes the target speed value to the target speed setting unit 54 in the SPM feedback control system shown in FIG. 1, thereby suppressing the SPM rotation fluctuation (disturbance D) during the load control. . In this system, the control gain is a constant value (G). Hereinafter, the control operation at the time of the load operation of the present embodiment will be described with reference to the flowchart of FIG.

First, the CPU 20 sets a target rotation speed value (TVa) higher than the normal target rotation speed value (TV) in the target speed setting section 54 (step S150).
The system uses the target rotation speed value (TVa) to execute a control operation at the time of starting the SPM 15 (step S151). That is, the SPM driver 21 uses the CPU 2
Target speed value (TVa) set by 0 and SPM
The start-up control is performed so that the error (E) from the rotation speed (RV) falls within an allowable range.

Next, the CPU 20 shifts to the above-described load control (step S152). That is, the CPU 20
Is obtained by detecting a sector pulse from the gate array 19.
It is monitored whether or not the head 12 has been loaded on the disk 10 (step S153). If the head 12 is not loaded onto the disk 10 even after the specified time has elapsed from the start of the load control, the CPU 20 determines that a failure has occurred and shifts to a predetermined error process (YES in step S157). .

On the other hand, when the CPU 20 confirms that the head 12 has been loaded onto the disk 10 by the load control, the CPU 20 changes the target speed value of the target speed setting unit 54 to a high-level target rotation speed value ( (TVa) to the normal target rotation speed value (TV), and shifts to the steady rotation control (YES in step S154, S155, S1).
56).

In such control operation, FIG.
The operation and effect of this embodiment will be described with reference to FIGS.

Normally, as shown in FIGS. 20A and 20B, the SPM feedback control system causes the actual SPM speed (RV) to follow the target speed value (TV). That is, as shown in FIG. 3C, the system performs feedback control so that the error (E) between the two becomes substantially zero. Here, as described above, when a disturbance (D) due to air friction between the head 12 and the disk 10 is added to the system during the load control, as shown in FIG. 21B, the actual SPM speed ( RV) is the target speed value (T
V) greatly decelerates. That is, as shown in FIG. 9C, the error (E) between the two becomes large toward the minus side.

Therefore, the system according to the present embodiment
In the period (Ts) from the start control to the load control (Ts), the target speed value is set in advance to a target speed value (TVa) higher than the normal target speed value (TV) (FIG. 22).
(A)). This allows the actual SPM speed (R
V) is controlled to follow a high-level target rotation speed value (TVa), so that the speed is higher than usual. Therefore,
When a disturbance (D) is added to the system during the load control, as shown in FIG. 22B, the actual SPM speed (R
V) decelerates, but is faster than normal. For this reason, the error (E) between them becomes a relatively small value as shown in FIG. Then, after the load control period (Ts) has elapsed, the system performs the normal target rotation speed value (Ts).
The process shifts to the steady rotation control using V).

In short, in the system of this embodiment, the target speed value is set to a value higher than usual from the time of starting until the end of the load control, thereby adding the disturbance (D) during the load control. On the other hand, it is possible to suppress the rotation fluctuation of the SPM 15 to the minus side.

[0098]

As described above in detail, according to the present invention, in a head load / unload type disk drive, a load operation for loading a head onto a disk is performed.
Rotational fluctuations of the spindle motor that rotates the disk can be suppressed. Therefore, after the loading of the head is completed, the spindle motor can be shifted to the steady rotation operation in a short time, and the data recording / reproducing operation can be executed. In particular, since the write operation can be permitted in a short time after the head has been loaded, the efficiency of the data recording operation can be improved as a result.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a main part of an HDD related to each embodiment of the present invention.

FIG. 2 is a diagram illustrating a structure of a lamp related to each embodiment.

FIG. 3 is a diagram for explaining a load operation related to each embodiment.

FIG. 4 is a view for explaining the relationship between the load operation and the rotation fluctuation of the SPM according to each embodiment.

FIG. 5 is a block diagram for explaining a configuration of an SPM feedback control system related to the first embodiment.

FIG. 6 is a flowchart for explaining a control operation at the time of SPM startup related to the system.

FIG. 7 is a flowchart for explaining a control operation at the time of a load operation related to the system.

FIG. 8 is a flowchart for explaining a control operation at the time of steady rotation control related to the system.

FIG. 9 is a flowchart illustrating a control operation at the time of a load operation according to a modification of the embodiment.

FIG. 10 is a flowchart for explaining a control operation at the time of steady rotation control related to a modification of the embodiment.

FIG. 11 is a view for explaining a load operation related to the second embodiment of the present invention.

FIG. 12 is a flowchart illustrating a control operation at the time of a load operation according to the second embodiment;

FIG. 13 is a flowchart for explaining a control operation at the time of steady-state rotation control related to the second embodiment.

FIG. 14 is a flowchart illustrating a control operation at the time of a load operation according to a modification of the second embodiment.

FIG. 15 is a flowchart illustrating a control operation at the time of steady-state rotation control according to a modification of the second embodiment.

FIG. 16 is a block diagram illustrating a configuration of an SPM feedback control system according to a third embodiment of the present invention.

FIG. 17 is a flowchart for explaining a control operation at the time of a load operation related to the third embodiment;

FIG. 18 is a flowchart for explaining a control operation at the time of an unload operation related to the third embodiment.

FIG. 19 is a flowchart illustrating a control operation at the time of a load operation according to a modification of the third embodiment.

FIG. 20 is a characteristic diagram for explaining a control operation of the SPM feedback control system according to the fourth embodiment of the present invention.

FIG. 21 is a characteristic diagram for explaining a control operation of an SPM feedback control system related to the fourth embodiment.

FIG. 22 is a characteristic diagram for explaining a control operation of the SPM feedback control system according to the fourth embodiment.

FIG. 23 is a flowchart illustrating a control operation of an SPM feedback control system according to the fourth embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Disk 11 ... Voice coil motor (VCM) 12 ... Head 13 ... Actuator 14 ... Lamp 15 ... Spindle motor (SPM) 16 ... Head amplifier IC 17 ... Read / write channel 18 ... Disk controller (HDC) 19 ... Gate array 20 ... CPU 21 ... SPM driver 22 ... VCM driver 23 ... Motor driver IC 131 ... Suspension 132 ... Tab

Claims (12)

[Claims] A spindle motor for rotating a disk; a head for recording and reproducing data on and from the disk; a ramp member for retracting the head from above the disk; A head moving mechanism for loading the head onto the disk from the ramp member and unloading the disk from the disk to the ramp member; and a head mounted on the disk during a loading operation by the head moving mechanism. Confirmation means for confirming that the operation has been performed, and means for driving and controlling the spindle motor, wherein the control gain is varied, and the disk is loaded when the head is loaded on the disk according to the recognition result of the confirmation means. Spindle motor control means for suppressing rotation fluctuation of the spindle within an allowable range. Disk storage device that. 2. The spindle motor control means sets the control gain to a normal gain at the time of starting rotation of the disk, and sets the control gain to suppress the rotation fluctuation when the head is loaded on the disk. 2. A means for setting the gain to a high level, and resetting the gain to the normal gain after suppressing the rotation fluctuation.
A disk storage device as described. 3. The disk storage device according to claim 1, wherein the confirmation unit confirms that the head has loaded onto the disk based on data read from the disk by the head. 4. The spindle motor control means resets the control gain to the normal gain after a lapse of a predetermined time after setting the control gain to a high level gain. Disk storage. 5. A control device comprising: a determination unit configured to determine a moving state of the head based on a change in a control current value of a voice coil motor included in the head moving mechanism; 2. The disk storage device according to claim 1, wherein it is confirmed that the head has loaded onto the disk based on the information. 6. A spindle motor for rotating a disk, a head for recording and reproducing data on the disk, a ramp member for retracting the head from above the disk, and holding the head. A head moving mechanism for loading the head from the ramp member onto the disk by the driving force of the voice coil motor and unloading the disk from the disk to the ramp member; and a change in a control current value of the voice coil motor. Determining means for determining a moving state of the head based on the following; checking means for confirming that the head has loaded onto the disk based on the determination result of the determining means; and means for controlling the drive of the spindle motor. At the start of rotation of the disk, the control gain is set to a normal gain, The control gain is set to a high-level gain in order to suppress rotation fluctuation when the head is loaded on the disk according to the recognition result of the checking means, and a predetermined time is set after setting the control gain to the high-level gain. And a spindle motor control means for resetting the control gain to the normal gain after a lapse of time. 7. A spindle motor for rotating a disk, a head for recording and reproducing data on and from the disk, a ramp member for retracting the head from above the disk, and holding the head, A head moving mechanism for loading the head onto the disk from the ramp member and unloading the disk from the disk to the ramp member; and a head mounted on the disk during a loading operation by the head moving mechanism. A spindle motor control means including a feedback control system for controlling the drive of the spindle motor based on a set target rotational speed; and Feedback control of disturbance correction value when loaded on A disk storage device, further comprising: a disturbance correction unit, which is added to the system and cancels the addition of the disturbance correction value when the head retreats from the disk during an unload operation by the head moving mechanism. 8. The disturbance correction means calculates a disturbance correction value for eliminating a disturbance caused by an air frictional force generated by a rotational motion of the disk when the head moves on the disk during rotation. And a means for adding the disturbance correction value as a calculation element to a calculation process for calculating an error value between the target rotation speed and the rotation speed of the spindle motor in the feedback control system. 8. The disk storage device according to 7. 9. A spindle motor for rotating a disk, a head for recording and reproducing data on and from the disk, a ramp member for retracting the head from above the disk, and holding the head. A head moving mechanism for loading the head onto the disk from the ramp member and unloading the disk from the disk to the ramp member; and a head mounted on the disk during a loading operation by the head moving mechanism. Confirmation means for confirming that the operation is to be performed, and means for controlling the drive of the spindle motor, wherein a target rotation speed used for drive control at the beginning of the load operation is set to a high level value, and the recognition result of the confirmation means Accordingly, when the head loads onto the disk, the target rotation speed is set to a normal value. Disk storage, characterized in that it comprises a Ndorumota control means. 10. A head load / unload type disk drive in which a head is loaded on a disk at the time of data recording / reproduction and the head is unloaded from the disk to a ramp member after recording / reproduction is completed. A spindle motor control device for performing drive control of a spindle motor for rotating a spindle motor, comprising: confirmation means for confirming that the head is positioned on the disk during the loading operation; and a target rotation speed and a rotation speed of the spindle motor. Means for calculating a control value required for drive control based on the error value and the control gain value, and setting the control gain value to a normal gain value at the time of rotation start, and the checking means The control gain value is set to a high level when the head is loaded on the disk according to the recognition result of A spindle motor control device comprising: gain variable means for setting a gain value and resetting the control gain value to the normal gain value after the error value is suppressed within an allowable range. 11. The method according to claim 11, wherein the gain variable means resets the control gain value to the normal gain value after a lapse of a predetermined time after setting the control gain value to the high-level gain. Item 11. The disk storage device according to item 10. 12. A head load / unload type disk drive in which a head is loaded on a disk during data recording and reproduction, and after the recording and reproduction is completed, the head is unloaded from the disk to a ramp member. A control method applied to a spindle motor control device for performing drive control of a spindle motor to be driven, comprising: at the time of rotation start, an error value between a target rotation speed and the rotation speed of the spindle motor; and a normal gain value set as a control gain. Performing a drive control based on the above, and, during a loading operation, setting the control gain to a high-level gain value when the head has loaded onto the disk, and setting the high-level gain value and the error value. Performing drive control based on Is reset to the normal gain value as the control gain after being suppressed within the allowable range,
Performing drive control based on the normal gain value and the error value.