JPH01213865A - Spindle motor controller for floppy disk device - Google Patents

Abstract

PURPOSE:To secure a chucking by controlling a spindle motor so as to be driven with a low revolving number, which is determined in advance, at the time of drive starting in a high density recording mode and to be driven with a high revolving number, which is determined in advance, after a prescribed time passes. CONSTITUTION:When a disk 10 of a high density recording system is inserted to a disk drive, a controller FDC20 detects a mark, which is added to the disk 10, and outputs a signal, which instructs a high revolving number mode, to a control circuit 24. A spindle motor 22 is revolved by the control circuit 24 through a driving circuit 23 and controlled with the low revolving number, which is determined in advance, at the time of revolution starting. Then, after the prescribed time passes, the spindle motor is normally revolved and driven with the revolving number to correspond to the high density recording mode. Thus, while the disk 10 is revolved and driven with the low revolving number, and the chucking of the disk is executed by a chucking mechanism 25 in a normal condition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a spindle motor control device for a floppy disk device for high-density recording.

(Prior Art) Conventionally, in a 3.5-inch floppy disk device, for example, when a magnetic recording medium (disk) is inserted into the device, it is chucked by a spindle mechanism and driven to rotate. The spindle mechanism is roughly divided into a chucking mechanism and a spindle motor. Here, as shown in FIG. 4 (plan view), the disk 10 includes a center hole 12 and a drive hole 13 formed in a hub 11 at the center.

The chaffing mechanism includes a spindle shaft 14 and a drive pin 15, and is configured such that the spindle shaft 14 fits into the center hole 12 of the disk 10, and the drive pin 15 fits into the drive hole 13.

The spindle shaft 14 and the drive pin 15 are rotationally driven by a spindle motor (not shown), and the disk 10 is rotationally driven by being fitted with the spindle shaft 14 and the drive pin 15, respectively.

By the way, when the disk 10 is inserted into the apparatus, it comes into contact with a magnetic head. The spindle shaft 14 and drive pin 15 are positioned with respect to the center hole 12 and drive hole 13 of the disk 10 by the contact friction force with the magnetic head.

With such positioning, the disk 10 is driven to rotate at a predetermined rotational speed. Here, the rotation speed is, for example, 30 ORPM (300 per minute) when the storage capacity of the disk lO is IMb (megabytes).
rotation). In the case of the storage capacity of IMb, the recording density is 50,000 bits per track of the disk 10, and the data transfer rate is 250 kb (bit)/s. That is, the rotation speed of the disk 10 is determined according to the bit recording density and the data transfer speed.

For this reason, in a high-density recording device with a storage capacity of 4 Mb, for example, the number of rotations of the disk IO is 150.
It has been increased to 0Rr'M. However, even in the case of the high-density recording method, since the size and structure of the disk IO are the same, the operation when the disk IO is chucked by the chucking mechanism is also the same. Such a chucking operation is performed at a rotation speed of 30 ORPM as described above.
It is suitable for low-density recording devices such as For this reason, in a high-density recording device with a rotation speed of 150 ORPM, etc., the disk 10 is not properly chucked by the chucking mechanism, and the center hole of the disk 10 is
If a sudden impact is applied to the drive hole 2 or the drive hole 13, problems such as ljl fR of each edge may occur. This is considered to be because when the rotational speed is high, the magnetic head tends to push up from the disk IO, and the contact friction force between the rotating disk IO and the magnetic head decreases.

(Problem to be solved by the invention) In the conventional high-density recording type floppy disk device,
Compared to a low-density recording system, the number of rotations of the disk 10 is significantly increased. For this reason, when the disk IO is chucked to the spindle mechanism, the disk IO is not chucked properly, resulting in damage to the structure such as the center hole 12 or drive hole 13 of the disk 0.

An object of the present invention is to enable a high-density recording type floppy disk device to reliably chuck a disk to a spindle mechanism, which is the rotating mechanism of the disk, thereby preventing damage to the structure of the disk. It is an object of the present invention to provide a spindle motor control device for a floppy disk device that can reliably prevent such a situation.

[Structure of the Invention] (Means and Effects for Solving the Problems) The present invention provides a floppy disk drive equipped with a spindle mechanism that chucks and rotationally drives a magnetic recording medium, in which the magnetic recording medium is adapted to a high-density recording mode. This device controls the motor drive control means that controls the rotation speed of the spindle motor accordingly.

In the high rotation speed mode, the motor drive control means drives the spindle motor at a low rotation speed at the start of driving to chuck the magnetic recording medium in the chucking mechanism, and after a predetermined time has elapsed from the start of driving, the spindle motor is driven at a predetermined high rotation speed. The spindle motor is controlled by the number.

With this configuration, in the case of high rotational speed mode, when chucking the magnetic recording medium, the magnetic recording medium is rotationally driven at low rotational speed to ensure chucking, and then the magnetic recording medium is rotated at low rotational speed to reliably chuck it, and then the magnetic recording medium is chucked at a high rotational speed corresponding to high-density recording mode. The magnetic recording medium is rotated by the rotational speed. Therefore, the magnetic recording medium can be properly chucked onto the spindle mechanism, and the magnetic recording medium can be rotated at a high rotational speed corresponding to the high-density recording mode.

(Example) The present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram showing a partial configuration of a floppy disk device according to the same embodiment. Floppy disk devices are broadly divided into disk drives (FDD) and controllers (FD).
C) consists of 20. FDD is a device that supports high-density recording mode, and as shown in FIG.
1. A motor drive circuit 23 and a control circuit 24 are provided for driving the spindle motor 22. The spindle mechanism 21 includes a spindle motor 22 and a chucking mechanism 2.
Consists of 5. The chucking mechanism 25 connects the spindle shaft 1
The chucking hub 2 supports the chucking hub 26 and the drive pin 15 provided around the chucking hub 4.
6 is provided with a leaf spring 28 fixed by a screw 27. The spindle shaft 14 is rotationally driven by a spindle motor 22.

The motor drive circuit 23 is a circuit that drives the spindle motor 22 under the control of the control circuit 24. Control circuit 2
Reference numeral 4 denotes a circuit that performs various control signals necessary for the operation of the FDD and transfer control of read/write data. FD
C20 is a circuit that exchanges various control signals and read/write data with the control circuit 24. In this embodiment, a mode signal instructing either high rotation speed mode or low rotation speed mode is sent to the control circuit 24. Output to 24.

Next, the operation of this embodiment will be explained. First, as shown in step S1 in FIG. 3, when the disk 10 is inserted into the FDD, the disk IO is moved toward the spindle mechanism 21 while being held by a receiver mechanism (not shown). At this time, depending on the recording density of the disk IO, the FDC20
For example, if the storage capacity is 4 Mb, a mode signal instructing a high rotation speed mode is output to the control circuit 24. In this case, a mark instructing the high-density recording mode is added to the disk IO in advance, and this mark is detected by an optical sensor or the like attached to the FDD in advance.

By outputting this detection signal to the FDC 20, the FDC 20 recognizes that it is in the high-density recording mode and outputs a mode signal.

The control circuit 24 starts the rotation of the spindle motor 22 through the motor drive circuit 23 (step S2). The control circuit 24 controls the rotation speed of the spindle motor 22 to increase to a predetermined speed of, for example, 300 RPM during a period of, for example, 0.2 to 0.5 seconds from the start of rotation (step S3). Here, the rotation speed of 300 RPM corresponds to a low density recording mode with a storage capacity of IMb, for example.

The disk IO is chucked by the chucking mechanism 25 while being rotationally driven at a rotation speed of 300 RPM.

That is, the disk 10 is rotated due to the contact friction force with the magnetic head (not shown) and the rotation speed corresponding to the low density recording mode.
As shown in FIG. 2, the spindle shaft 14 is fitted into the center hole 12, and the drive pin 1 is fitted into the drive hole 13.
5 are chucked so that they fit together. Thereafter, the control circuit 24 controls the rotation speed of the spindle motor 22 to 1, for example, according to the high-density recording mode through the motor drive circuit 23.
The speed is increased to 500 RPM (step S5). As a result, the disk 10 is chucked to the spindle mechanism 21, and the disk 10 is set to 1500 yen according to the high-density recording mode.
Steady rotation is driven at the rotation speed of RPM (step S6)
.

In this way, for example, when performing one read/write operation on the disk 10 in the high density recording mode with a storage capacity of 4 Mb, immediately after the disk 1o is inserted, the rotation speed corresponding to the low density recording mode is set. (For example, 30 ORP
M) rotates the disk IO. As a result, the disk lO
is chucked by the chucking mechanism 25 of the spindle mechanism 21 in a normal state. Therefore, unlike the case where the disk is chucked at a high rotational speed corresponding to the high-density recording mode, it is possible to reliably prevent a situation such as damage to the edge of the center hole 12 or drive hole 13 of the disk 1o. .

After the disk lO is chucked by the spindle mechanism 21, it is recorded with a recording speed of, for example, 1500, which corresponds to the high-density recording mode.
Rotationally driven at high RPM speed.

Therefore, read/write operations in the high-density recording mode are reliably performed on the disk 10.

In addition, when the disk 1o corresponding to the low-density recording mode is loaded and a read operation is performed in the FDD in the high-density recording mode, the spindle motor 22 rotates at a rotation speed of 300 RPM or the like corresponding to the low-density recording mode. Therefore, it is rotated both at the start and during steady state.

[Effects of the Invention] As detailed above, according to the present invention, when chucking a disk to a spindle mechanism in a floppy disk device in a high-density recording mode, an appropriate rotational speed corresponding to a low-density recording mode can be achieved. chucking can be performed in a normal state. Therefore, it is possible to reliably prevent damage to the structure of the disk during chucking. Further, after chucking, the disk is rotated at a rotational speed corresponding to the high-density recording mode, so that read/write operations corresponding to the high-density recording mode can be reliably executed.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a partial configuration of a floppy disk device according to an embodiment of the present invention, FIG. 2 is a plan view for explaining the operation of the embodiment, and FIG. 3 is a diagram illustrating the operation of the embodiment. FIG. 4 is a flow chart for explaining the conventional method. ”0... Disc, 12... Center hole, 13
... Drive hole, 14 ... Spindle shaft, 15
... Drive pin, 22 ... Spindle motor, 2
4... Control circuit, 25... Chucking mechanism. Applicant's representative Patent attorney Takehiko Suzue 14th C) Niru Axis @1 Figure 2 Figure 3

Claims (1)

[Scope of Claims] A floppy disk device that performs read/write operations on a magnetic recording medium in accordance with a high-density recording mode, comprising: a chucking mechanism for holding a magnetic recording medium set in the device; and this chucking mechanism. a spindle mechanism including a spindle motor that rotationally drives the magnetic recording medium chucked in the magnetic recording medium; a motor drive control means that controls the spindle motor to be driven to chuck the magnetic recording medium in the chucking mechanism and to drive the spindle motor at a predetermined high rotational speed after a predetermined time has elapsed from the start of the drive; A spindle motor control device for a floppy disk device, characterized in that: