JPH09320181A - Spindle motor control method and control system for high density / normal density type flexible disk drive - Google Patents

Abstract

(57) An object of the present invention is to automatically rotate a magnetic disk medium of an inserted FD at a rotation speed suitable for it. A controller 60 includes a switch unit 50.
A logic circuit 61 which selectively outputs one of the low speed selection signal S _L and the high speed selection signal S _H in response to the detection signal from the circuit, a clock generation circuit 62 which generates a clock signal CLK, and a clock signal It has a spindle motor driver 63 for driving the spindle motor 100 based on the CLK, the FG signal, the low speed selection signal S _L and the high speed selection signal S _H. The low speed selection signal S _L is a signal for instructing to rotate the inserted magnetic disk medium of the FD at a low speed (300 rpm).
_H is a high-speed (3
It is a signal instructing rotation at 600 rpm).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk medium of a large capacity flexible disk which needs to be rotated at a high speed during recording and reproduction, and a magnetic disk medium of a normal capacity flexible disk which needs to be rotated at a low speed during recording and reproduction. High density / recording / reproducing data for both
Regarding the standard density combined use type flexible disk drive,
In particular, the present invention relates to a spindle motor control method and control system used in a high density / normal density combined type flexible disk drive.

[0002]

2. Description of the Related Art As is well known, a flexible disk drive is a device for recording / reproducing data on / from a magnetic disk medium of a flexible disk inserted therein. In recent years, the capacity of a flexible disk has been increased, and a storage capacity of 1 M to 2 M bytes (hereinafter,
A memory having a storage capacity of 128 Mbytes (hereinafter referred to as a large capacity) has been developed in comparison with a memory having a normal capacity. Along with this, a flexible disk drive that can record and reproduce data on and from such a magnetic disk medium having a large capacity flexible disk has been developed.

Hereinafter, a flexible disk drive capable of recording and reproducing data only on a magnetic disk medium of a large-capacity flexible disk is referred to as a high-density-dedicated flexible disk drive. A flexible disk drive capable of recording and reproducing data is generally referred to as a density-only flexible disk drive. Furthermore, a flexible disk drive capable of recording and reproducing data on a magnetic disk medium of both large-capacity and normal-capacity flexible disks will be referred to as a high-density / normal-density flexible disk drive. When the high-density dedicated flexible disk drive and the high-density / normal density combined-type flexible disk drive are not distinguished, they are simply referred to as the high-density flexible disk drive.

One of the major mechanical differences between the normal-density dedicated type flexible disk drive and the high-density type flexible disk drive is that the carriage holding the magnetic head is inserted into the flexible disk drive. The drive means is configured to move along a predetermined radial direction (radial direction of the magnetic disk medium) with respect to the disk.
That is, while a stepping motor is used as a driving means in a normal-density type flexible disk drive, a linear motor such as a voice coil motor (VCM) is used as a driving means in a high-density type flexible disk drive. I have.

The voice coil motor used as the driving means for the high-density flexible disk drive will be described in detail below. The voice coil motor is disposed behind the carriage and wound around a drive shaft parallel to a predetermined radial direction, and a magnetic circuit for generating a magnetic field crossing a current flowing through the boil coil. Having. With such a configuration, by causing a current to flow through the boil coil in a direction crossing the magnetic field generated by the magnetic circuit, a driving force is generated in the extending direction of the drive shaft based on the interaction between the current and the magnetic field. . With this driving force, the voice coil motor moves the carriage along a predetermined radial direction.

Another major difference between the normal density dedicated type flexible disk drive and the high density type flexible disk drive is the rotation of the spindle motor rotating the magnetic disk of the inserted flexible disk drive. In number. That is, in the normal density dedicated type flexible disk drive, since the flexible disk to be inserted is limited to the normal capacity flexible disk, the spindle motor for the flexible disk drive uses the magnetic disk medium of the inserted flexible disk.
It may be rotated at a low speed of rpm or 360 rpm. On the other hand, in the high density type flexible disk drive, the flexible disk to be inserted may be only the large capacity flexible disk or both the large capacity flexible disk and the normal capacity flexible disk. Therefore, when the inserted flexible disk is a large-capacity flexible disk, the high-density flexible disk drive spindle motor rotates the magnetic disk medium at a rotation speed of 3600 rpm, which is 12 to 10 times that of the normal-capacity flexible disk. You have to double the speed.

The high density / normal density combined type flexible disk drive requires a means for discriminating and detecting whether the flexible disk inserted therein is a large capacity flexible disk or a normal capacity flexible disk.

[0008]

As described above, in the high density / normal density combined type flexible disk drive, in order to rotate the magnetic disk medium of the flexible disk inserted therein by the spindle motor, the inserted flexible disk Magnetic disk media of the disk,
There is a need to provide a spindle motor control method and a control system for a high density / normal density combined type flexible disk drive, which can be automatically driven to rotate at a rotation speed suitable for this.

[0009]

According to the present invention, a magnetic disk medium of a large-capacity flexible disk that needs to be rotated at a high speed during recording and reproduction and a magnetic disk medium that is rotated at a low speed much lower than the high speed during recording and reproduction. A method for controlling a spindle motor used in a high-density flexible disk drive for recording / reproducing data to / from a required normal capacity flexible disk magnetic disk medium, wherein the high-density / normal-density flexible disk is used. Discriminating and detecting whether the flexible disk inserted in the disc drive is the large-capacity flexible disc or the normal-capacity flexible disc; and the inserted flexible disc is discriminated and detected as the large-capacity flexible disc. When the spindle mode And rotating the spindle motor at the high speed, and drivingly controlling the spindle motor to rotate at the low speed when the inserted flexible disk is identified and detected as the normal capacity flexible disk. / A spindle motor control method for a normal density / flexible flexible disk drive can be obtained.

Further, according to the present invention, a magnetic disk medium of a large-capacity flexible disk that needs to be rotated at a high speed during recording and reproduction and a normal disk that needs to be rotated at a low speed much lower than the high speed during recording and reproduction. A control system of a spindle motor used for a high density / normal density combined type flexible disk drive for recording / reproducing data to / from both a magnetic disk medium of a capacity flexible disk, wherein the high density / normal density combined type flexible system Identification detection means for identifying and detecting whether the flexible disk inserted in the disk drive is the large capacity flexible disk or the normal capacity flexible disk, and the inserted flexible disk has the large capacity by the identification detection means. Identified as a flexible disk When it is detected, the spindle motor is rotated at the high speed, and when it is detected that the inserted flexible disk is the normal capacity flexible disk, the spindle motor is controlled to rotate at the low speed. A spindle motor control system for a high density / normal density type flexible disk drive including a control device is obtained.

[0011]

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

Referring to FIG. 2, description will be given of a high density / normal density combined type flexible disk drive to which the spindle motor control method according to the present invention is applied. The illustrated high density / normal density combined type flexible disk drive (FDD) is a device for recording / reproducing data on / from both a large capacity flexible disk magnetic disk medium and a normal capacity flexible disk magnetic disk medium described later. The flexible disk is inserted into the high density / normal density combined type flexible disk drive from the direction indicated by arrow A in FIG. The inserted flexible disk is held on the disk table 12 rotatably supported on the surface of the main frame 11 with their central axes aligned with each other. The disk table 12 is rotationally driven by a spindle motor (described later) provided in a recessed portion (described later) of the main frame 11 so that the magnetic disk medium of the flexible disk is rotated. Also, the main frame 11
A printed wiring board (not shown) on which a large number of electronic components are mounted is attached to the back surface of the.

The high density / normal density combined type flexible disk drive has a magnetic head (not shown) for reading / writing data from / to the magnetic disk medium of the flexible disk. The magnetic head is gimbal 14
It is held by the carriage 15 via. The combination of the magnetic head, gimbal 14, carriage 15, voice coil 17 (described later), FPC (flexible printed circuit), scale, spring holder, and spring is called a carriage assembly. The carriage 15 is arranged on the surface of the main frame 11 so as to be separated from the main frame 11, and allows the magnetic head to move along a predetermined radial direction (direction shown by arrow B in FIG. 2) with respect to the flexible disk. keeping.

The carriage 15 is supported and guided at its lower ends on both sides by a pair of guide bars 16 extending parallel to a predetermined radial direction B.

The carriage 15 is driven along a predetermined radial direction B by a voice coil motor as described below. More specifically, the voice coil motor is disposed behind the carriage 15 and has a predetermined radial direction B.
It has a pair of voice coils 17 wound around a drive axis parallel to and a magnetic circuit 20 for generating a magnetic field intersecting with the current flowing through the boil coil 17.
In the voice coil motor having such a configuration, a current is caused to flow through the boil coil 17 in a direction crossing the magnetic field generated by the magnetic circuit 20, so that the direction of extension of the drive shaft is determined based on the interaction between the current and the magnetic field. A driving force is generated.
This driving force causes the voice coil motor to move the carriage 1
5 is moved in a predetermined radial direction B.

Next, a spindle motor used in a high density / normal density combined type flexible disk drive will be described with reference to FIG. In FIG. 3, (A)
FIG. 1B is a plan view, and FIG. 1B is a cross-sectional view of the rotor taken along line CC and the stator taken along line DD.

The illustrated spindle motor 100 is of a type mounted on the surface of the main frame 11 (that is, the surface on which a flexible disk (not shown) is inserted), not the back surface of the main frame 11. In particular, it is a type that is attached in a state of being embedded in the recess 11a of the main frame 11.

The main frame 11 has a substantially cylindrical bearing metal 102 in the recess 11a.
Are erected substantially perpendicular to the main surface of the main frame 11. In the bearing metal 102, a spindle shaft 104 is provided with a ball bearing 106 in a state substantially perpendicular to the main surface of the main frame 11.
And is rotatably supported by the main frame 11 via the. This spindle shaft 104 has a high density /
Normally, the flexible disk inserted in the dual-purpose flexible disk drive functions as the rotation axis O of the magnetic disk medium. A disk-shaped disk table 12 is fitted on the upper end side of the spindle shaft 104, and the main surface of the disk table 12 extends in a direction orthogonal to the longitudinal direction of the spindle shaft 104 (the rotation axis O direction). .

That is, the disk table 12 is rotatably supported on the surface of the main frame 11 and has a high density /
The flexible disk inserted in the normal-density dual-purpose flexible disk drive is held in a state where the suspension axes (rotational axes A) of the flexible disks are aligned with each other.

FIG. 4 is a plan view of the large capacity flexible disk 40 as viewed from the back side. As shown in FIG. 4, the large-capacity flexible disk 40 has a magnetic disk medium 41 as a magnetic recording medium and a case 42 that covers the magnetic disk medium 41. A circular opening 42a is opened at the center of the back side of the case 42. A disk hub (disc-shaped metal fitting) 43 holding the magnetic disk medium 41 is loosely inserted into the circular opening 42a. In the center of the disk hub 43, a disk center hole 43a through which the spindle shaft 104 is freely inserted, and a chucking pin (drive roller) to be described later is freely inserted in a peripheral position shifted from the disk center hole 43a. A chucking hole (a disc-side driving long hole) 43b is formed.

Returning to FIG. 3, the diameter of the disk table 12 is longer than the diameter of the disk hub 43 and the circular opening 4 is formed.
2a.

The disk table 12 is provided with a table-side driving elongated hole 12a at a position corresponding to the chucking hole (disk-side driving elongated hole) 43b. The chucking pin (drive roller) 108 passes through the chucking hole 43b through the table-side driving slot 12a. The chucking pin 108 is rotatably attached to one end of a flexible arm 112 of a magnet case 110 attached to the lower surface of the disc table 12 via a holding portion 114 while being biased upward. There is. Therefore, when a load is applied to the chucking pin 108 from above, the chucking pin 108 moves downward (sinks).

The magnet case 110 is made of iron,
A disk portion 116 formed in a substantially tray shape by pressing and extending parallel to the extending direction of the disk table 12, and an outer peripheral wall 118 bent downward at the outer peripheral end of the disk portion 116.
Consisting of A ring-shaped main magnet 120 is fixed to the inner side surface of the outer peripheral wall 118.

At any rate, the spindle motor 104 is constituted by the spindle shaft 104, the disk table 12, the chucking pin 108, the magnet case 110, the arm 112, the holding portion 114, and the main magnet 118.
0 rotor is configured.

The bearing metal 102 has a flange portion 102a. A core 122 is fixed and mounted on the flange portion 102a by a screw (not shown). The core 122 has a plurality of magnetic pole forming portions 122a extending radially at equal intervals. A coil 124 is wound around each magnetic pole forming part 122a. That is, the magnetic pole forming portion 122a
And the coil 124 are combined to form an electromagnet (magnetic pole)
Is formed. This electromagnet has a predetermined gap
The main magnet 120 is disposed so as to face the above. Anyway, the stator of the spindle motor 100 is constituted by the core 122 and the coil 124.

A substantially rectangular parallelepiped index detecting magnet 128 is fixed at an arbitrary position on the outer surface of the outer peripheral wall 118 of the magnet case 108. In addition, the printed wiring board 12 is provided in the recess 11 a of the main frame 11.
6 is fixedly housed by a screw (not shown). A magnetic sensor (not shown) that detects the magnetism from the index detecting magnet 128 is arranged on the printed wiring board 126.

Further, the illustrated spindle motor 100
Is provided with a balancer 130 as balance means. This balancer 130 is used for the spindle shaft 104.
On the opposite side of the chucking pin 108,
It is attached to the lower surface of the magnet case 110.
Thereby, the center of gravity G of the rotor is made to coincide with the rotation axis O,
The rotor is balanced during rotation (especially during high-speed rotation).

Referring again to FIG. 4, in the case 42 of the large-capacity flexible disk 40, when viewed from the back surface side, the right corner of the rear end in the insertion direction (when viewed from the front surface side). A write protection hole (not shown) is formed in the left corner. FIG. 4 shows a state in which the write protection hole is closed by the write protection tab 44. The write protection tab 44 is slidable in the insertion direction. By manually operating the write protection tab 44, the write protection hole can be opened and closed. When the write-protection tab 44 closes the write-protection hole, recording is enabled, and when the write-protection hole is opened, recording is disabled.

The illustrated large capacity flexible disk 40
Has two types of storage capacity (for example, 128 MB and 25 MB
6 M bytes). A large capacity identification detection hole 45 is formed near the write protection hole.
The large capacity discriminating / detecting hole 45 is for identifying the large capacity flexible disk 40 and the normal capacity flexible disk. Further, a hole 46 for type identification detection is selectively formed near the hole for write protection together with the hole 45 for large capacity identification detection. The type identification detection hole 46 is for identifying the type of the large-capacity flexible disk 40, and the type of the large-capacity flexible disk 40 can be identified by its presence or absence. For example, the recording capacity is 12
In the case of a large capacity flexible disk of 8 Mbytes,
The type identification detection hole 46 is not formed in the case 42, and in the case of a large-capacity flexible disk having a recording capacity of 256 Mbytes, the type identification detection hole 46 may be formed in the case 42. .

Although not shown, as is well known, a large capacity discriminating and detecting hole 45 is formed in the normal capacity flexible disk.
The type identification detection hole 46 is not formed.

Returning to FIG. 2, in the high density / normal density combined type flexible disk drive, the switch unit 50 is further mounted on the printed wiring board (not shown) at the left corner of the rear end in the insertion direction. There is. The switch unit 50 includes a push switch. The switch unit 50 is for detecting the write protection hole, the large capacity identification detection hole 45, and the type identification detection hole 46.

More specifically, the switch unit 50
Has a write control switch 51, a large capacity identification switch 52, and a type identification switch 53. The write control switch 51 is a switch for detecting the open / close state of the write protection hole, and is provided at a position corresponding to the write protection hole. The large capacity identification switch 52 is a switch for identifying and detecting whether the inserted flexible disk is the large capacity flexible disk 40 or the normal capacity flexible disk, and is provided at a position corresponding to the large capacity identification detection hole 45. ing. The type identification switch 53 is a switch for detecting the presence or absence in the type identification detection hole 46, and is provided at a position corresponding to the type identification detection hole 46.

Although not shown, the stator of the spindle motor 100 has a frequency generation pattern (hereinafter, abbreviated as FG pattern) for detecting the rotational speed thereof.
Are arranged. This FG pattern generates an FG signal having 60 pulses while the spindle shaft 104 of the spindle motor 100 makes one rotation. As is well known, 300 rpm is equal to 5 Hz / rev and 3600
rpm is equal to 60 Hz / rev. Therefore, the magnetic disk medium of the normal capacity flexible disk has a specified rotation speed of 30 by the spindle motor 100.
When rotating at 0 rpm, the FG pattern is 300 Hz
FG signal is generated. Similarly, the magnetic disk medium of the large capacity flexible disk 40 is the spindle motor 10
When the FG pattern is rotating at 3600 rpm, which is its specified rotation speed by 0, the FG pattern generates an FG signal of 3600 Hz.

FIG. 1 shows a spindle motor control system according to an embodiment of the present invention. The control device 60 receives the detection signal from the switch unit 50, and selectively outputs one of the low speed selection signal S _L and the high speed selection signal S _H , as will be described later, and 1 MHz.
A clock generation circuit 62 for generating a clock signal CLK having a clock frequency of, and a spindle motor driver for driving the spindle motor 100 based on the clock signal CLK, the FG signal, the low speed selection signal S _L and the high speed selection signal S _H. And 63.

The low speed selection signal S _L is a signal for instructing to rotate the inserted flexible disk (FD) magnetic disk medium at a low speed (300 rpm), and the high speed selection signal S _H is inserted. It is a signal instructing to rotate the magnetic disk medium of the FD at a high speed (3600 rpm).

The spindle motor driver 63 is composed of a phase synchronization circuit (PLL) 631 and a drive transistor 632. Phase synchronization circuit 631 includes a frequency divider (not shown) that divides clock signal CLK. Low speed selection signal S
_In response to _L , the divider divides the clock signal CLK having a clock frequency of 1 MHz into a divided signal having a dividing frequency of 300 Hz. Similarly, in response to the high speed selection signal S _H, the divider a clock signal CLK having a clock frequency of 1MHz is divided frequency dividing the divided signal 3600 Hz. The phase synchronization circuit 631 compares the FG signal with the frequency-divided signal and outputs a control signal indicating a phase difference between the signal and the frequency-divided signal.
The drive transistor 632 drives the spindle motor 100 based on this control signal. That is, the spindle motor driver 63 sets the spindle motor 10 so that the frequency of the FG signal matches the frequency division frequency of the frequency division signal.
Drive 0.

Next, a spindle motor control method according to an embodiment of the present invention will be described with reference to FIG.

It is assumed that the large capacity flexible disk 40 (FIG. 4) is inserted in the high density / normal density combined type flexible disk. In this case, the flexible disk inserted by the switch unit 50 is identified and detected as the large capacity flexible disk 40, and the switch unit 50 sends a detection signal indicating that the large capacity flexible disk 40 has been identified and detected to the logic circuit 61. To do.
The logic circuit 61 sends the high speed selection signal S _H to the phase synchronization circuit 631 in response to this detection signal. In response to the high speed selection signal S _H , the spindle motor driver 6
3 drives the spindle motor 100 to rotate at a high speed of 3600 rpm.

On the other hand, it is assumed that the normal capacity flexible disk is inserted in the high density / normal density combined type flexible disk. In this case, the flexible disk inserted by the switch unit 50 is identified and detected as a normal capacity flexible disk, and the switch unit 50 sends a detection signal indicating that the flexible disk has been identified and detected to the logic circuit 61. To do. The logic circuit 61 sends the low speed selection signal S _L to the phase synchronization circuit 631 in response to this detection signal. In response to the low speed selection signal S _L , the spindle motor driver 63 drives the spindle motor 100 to rotate at a low speed of 300 rpm.

In this way, the type of the inserted flexible disk is discriminated and, based on the discrimination result, the magnetic disk medium of the inserted flexible disk is automatically rotated by the spindle motor at a rotation speed suitable for the disc. It is driving.

In the above embodiment, the speed of the spindle motor 100 is switched by switching the frequency division ratio of the phase control circuit 631, but it can also be switched by switching the clock frequency of the clock generator 62. it can. Alternatively, two low-speed phase-locked circuits and a high-speed phase-locked circuit may be prepared as the phase-locked circuits, and these may be switched by a switch to select the speed.

[0042]

As is apparent from the above description, according to the present invention, the type of the inserted flexible disk is discriminated, and the magnetic disk medium of the inserted flexible disc is set to the spindle motor based on the discrimination result. With this, there is an effect that it can be automatically rotationally driven at a rotational speed suitable for it.

[Brief description of drawings]

FIG. 1 is a block diagram showing a spindle motor control system according to an embodiment of the present invention.

FIG. 2 is a plan view showing a high density / normal density combined type flexible disk drive to which the spindle motor control method according to the present invention is applied.

3A and 3B are diagrams showing in detail a spindle motor used in the high density / normal density combined type flexible disk drive shown in FIG. 2, in which FIG. 3A is a plan view and FIG. 3B is a rotor line CC line. FIG. 6 is a sectional view of the stator side taken along the line D-D.

4 is a plan view of a large-capacity flexible disk accessed by the high-density / normal-density dual-purpose flexible disk drive shown in FIG. 2, as viewed from the back side.

[Explanation of symbols]

 40 large capacity flexible disk 50 switch unit 60 controller 61 logic circuit 62 clock generator 63 spindle motor driver 100 spindle motor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshimitsu Ito 1601 Sakai, Atsugi, Kanagawa Mitsumi Electric Co., Ltd. Atsugi Plant

Claims (6)

[Claims] 1. A magnetic disk medium of a large capacity flexible disk which needs to be rotated at a high speed during recording and reproduction, and a magnetic disk of a normal capacity flexible disk which needs to be rotated at a low speed much lower than the high speed during recording and reproduction. A method for controlling a spindle motor used in a high-density flexible disk drive for recording / reproducing data on / from a medium, wherein the flexible disk inserted in the high-density / normal density dual-purpose flexible disk drive is Discriminating and detecting whether it is a large-capacity flexible disc or the normal-capacity flexible disc; and when the inserted flexible disc is discriminated and detected as the large-capacity flexible disc, the spindle motor is operated at the high speed. Rotate the above A high density / normal density combination type flexible disk drive spindle, which includes the step of controlling the spindle motor to rotate at the low speed when the inserted flexible disk is identified and detected as the normal capacity flexible disk. Motor control method. 2. The spindle motor control method for a high density / normal density combined type flexible disk drive according to claim 1, wherein the high speed is 10 times or more the low speed. 3. The high-speed rotation speed is 3600 rpm.
3. The spindle motor control method for a high density / normal density combined type flexible disk drive according to claim 2, wherein the rotation speed at the low speed is 300 rpm. 4. A magnetic disk medium of a large capacity flexible disk which needs to be rotated at a high speed during recording and reproduction, and a magnetic disk of a normal capacity flexible disk which needs to be rotated at a low speed much lower than the high speed during recording and reproduction. A spindle motor control system used in a high-density / normal-density flexible disk drive for recording / reproducing data to / from a medium, which is inserted in the high-density / normal-density flexible disk drive. Identification detecting means for identifying and detecting whether the flexible disk is the large capacity flexible disk or the normal capacity flexible disk, and the inserted flexible disk is identified as the large capacity flexible disk by the identification detecting means. Before when detected A control device for rotating the spindle motor at the high speed, and drivingly controlling the spindle motor to rotate at the low speed when the inserted flexible disk is identified and detected as the normal capacity flexible disk. Spindle motor control system for high density / normal density flexible disk drive. 5. The spindle motor control system for a high density / normal density combination type flexible disk drive according to claim 4, wherein the high speed is 10 times or more as high as the low speed. 6. The rotation speed of the high speed is 3600 rpm
6. The spindle motor control system for a high density / normal density combined type flexible disk drive according to claim 5, wherein the low speed rotation speed is 300 rpm.