JPS6313178A - Head positioning device for disk device - Google Patents

Abstract

PURPOSE:To establish accurate position setting by moving a head from a position shifted unidirectionally from a home position into the home position and applying setting when a position sensor detects the home position. CONSTITUTION:A detection signal from a photointerrupter 8 is read by a microcomputer 9 after application of power, and when the photointerruptor 8 detects a light shield plate 12, a drive circuit 7 is controlled to drive a step motor 4 by one step, heads 5a, 5b are forwarded by one track until the interrupter 8 detects nothing, the microcomputer 9 reverses the heads 5a, 5b by one step toward the original direction and sets the position detecting the light shield plate 12 as the home position of the heads 5a, 5b. When no light shield plate 12 is detected, the heads 5a, 5b are reversed by one step each toward the direction of 0 track and the point of time at the home position is detected by the interrupter 8 and the light shield plate 12 and the position stopping the reversing is set as the home position.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a head positioning device in a floppy disk device, a magnetic disk device, an optical disk device, or the like.

[Prior Art] A step motor is often used as a head actuator for a floppy disk device or a magnetic disk device. In such a disk device, the head is first set at a reference position called a zero track, and then driven from that position by a predetermined number of steps to position the head on a target track.

Therefore, when the power of the disk device is turned on, the microcomputer that controls the step motor detects the position of the head, and if the head is not at the reference position,
The head actuator is driven to position the head at a reference position. In this case, the detection of whether the head is at the reference position is carried out by providing a position sensor such as a photo interrupter or a mechanical contact that detects the position of the carriage on which the head is mounted or the rotation angle of the step motor.

However, the above-mentioned position sensors only determine whether the object to be detected is within a certain range, and cannot be determined even if the object is displaced within the above range. Therefore, when detecting the reference position of the head in the above, even if the head deviates from the reference position within the above range due to vibration or shock applied to the device while the power is off, the head is determined to be at the reference position. The shifted position is set as the reference position, and as a result, off-track occurs because the head is moved a predetermined step from that position to position the head on the target track.

As described above, the conventional disk device has a problem in that the head cannot be accurately set at the reference position.

[Objective] An object of the present invention is to provide a head positioning device for a disk device that can solve the above problems and accurately set the head at a reference position.

[Configuration] Therefore, in the present invention, when setting the head to the reference position,
The head is always shifted in a certain direction from the reference position and moved in the direction of the reference position, and when the head position sensor detects the reference position, the movement is stopped and the reference position is set. It is characterized by the fact that

Examples of the present invention will be described in detail below.

FIG. 1 is a block diagram of a head positioning device for a magnetic disk device according to an embodiment of the present invention. This device is unitized and installed in a computer system (not shown), and power is supplied from the main body. In the figure, l is a spindle motor that rotates the magnetic disk 2.

3 is a spindle motor drive circuit that rotates the spindle motor l at a predetermined speed. 4 is the read/write head (
A step motor drives a carriage 6 on which the heads (hereinafter simply referred to as heads) 5a and 5b are mounted, and 7 is a step motor drive circuit that drives the step motor 4.

Reference numeral 8 denotes a photointerrupter that detects the reference position of the heads 5a and 5b from the rotation angle of the step motor 4.

The microcomputer 9 inputs the detection signal of the photointerrupter 8 and controls the spindle motor drive circuit 3 and the step motor drive circuit 7, as well as an information recording and reproducing section (not shown) and an interface circuit, thereby controlling the host side (not shown). Data is transferred to and from a computer in a predetermined sequence.

The carriage 6 has a pedestal frame 6a as shown in FIG.
A head support part 6b is fixed to the upper part of the head support part 6b, and a bearing 6c is attached to the lower part of the head support part 6b. Also, bearing 6C
and the carriage rod 10 are engaged with each other, and the single pedestal frame 6a and the rotating shaft of the step motor 4 are connected by a steel belt 11.

As a result, the step motor 4 is rotated to move the carriage 6 along the carriage rod lO, and the head 5a attached to the end of the arm of the head support section 6b,
5b (not shown) can be moved onto any track on the magnetic disk 2.

In the above movement, when the heads 5a and 5b return from each data track to the 0 track, which is the reference position, when the heads 5a and 5b reach exactly 1 track above the 0 track, the light shielding plate 12 attached to the rotating shaft of the step motor 4 The detection light inside the photointerrupter 8 is blocked, and the reference position is detected.

The head positioning device for the disk drive of this embodiment has the above configuration, and the reference position of the head is set by the operation shown in FIG. 3 when the power is turned on. Namely.

When the power is turned on, the microcomputer 9 reads the detection signal from the photointerrupter 8.

It is determined whether the photointerrupter 8 has detected the light shielding plate 12 (process 21 in FIG. 3).

Here, when the photointerrupter 8 is detecting the light shielding plate 12 (v in process 21), the step motor drive circuit 7
is controlled to rotate the step motor 4 by one step, and advance the heads 5a and 5b in the direction of one track (
Process 22) and then return to process 21 above.

As a result, the heads 5a and 5b are moved forward until the photointerrupter 8 no longer detects the light shielding plate 12.

When the light shielding plate 12 is no longer detected (N of process 21)
, the microcomputer 9 has the head 5a, contrary to the above.
, 5b is moved one step in the original direction (process 23
). Next, it is confirmed that the photointerrupter 8 detects the light shielding plate 12, and the operation ends (Y in process 24).

In this way, when the light shielding plate 12 has already been detected in the power-on process 21 (Y in process 21), the heads 5a and 5b are operated until the light shielding plate 12 is no longer detected.
is advanced in the direction of one track, and then the head 5a is moved forward.

5b back one step in the original direction. This results in
The position where the light shielding plate 12 is detected is set as the reference position of the heads 5a and 5b.

On the other hand, in the above process 21, if the light shielding plate 12 is not detected (N in process 21), the heads 5a and 5b are moved back one step at a time in the direction of the O track (from process 23 to process 24 N), and the light shielding plate 12 is detected. The above-mentioned retreat is stopped at the detected position (Y in process 24), thereby setting the reference position in the same manner as above.

As described above, in this embodiment, when the power is turned on, the heads 5a and 5b are always moved back one step at a time from the 1 track side to the O track side, which is the reference position, and when the heads 5a and 5b enter the reference position, is detected by the photointerrupter 8 and the light shielding plate 12, and the head 5a is stopped at that point and set as the reference position for the heads 5a and 5b.As a result, the head 5a is always kept at a constant reference position.

5b can be set.

In addition, in this embodiment, when the power is turned on, the head 5a,
Although the reference position setting in 5b has been described, the present invention can be applied not only when the power is turned on. Furthermore, although we have shown an example in which a pulse motor is used as the head actuator, it is also possible to use a voice coil motor or the like to move the head actuator continuously rather than in steps, and to stop the head actuator at the moment the light shielding plate is detected. . Furthermore, the present invention can be widely applied not only to magnetic disk devices but also to storage devices having a structure in which heads are moved.

[Effects] As described above, according to the present invention, when setting the head to the reference position, the head is always shifted from the reference position in a certain direction to the reference position, and the head position sensor detects the reference position. Since the head is stopped at the point at which the reference position is set, the head can be accurately set at the reference position.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a head positioning device for a magnetic disk drive according to an embodiment of the present invention, FIG. 2 is a perspective view of the vicinity of a step motor, and FIG. 3 shows a head reference position setting operation when the power is turned on. It is a flowchart. 1... Spindle motor, 2... Magnetic disk, 3
...Spindle motor drive circuit, 4...Step motor, 5a, 5b... Read/write head, 6.
... Carriage, 7... Step motor drive circuit,
8... Photo interrupter, 9... Microcomputer, 10... Carriage rod, 11...
Steel belt, 12...shading plate. Figure 2 Figure 3

Claims (1)

[Claims] A rotating information recording medium, a head that moves on each data track of the information recording medium, a head actuator that drives the head, and a position sensor that detects the reference position of the head using one of binary signals. , initial position setting means for driving the head in one direction until the output signal from the position sensor indicates one of the binary signals, the output signal is inverted to the other of the binary signals; and and a reference position setting means for driving the head in the opposite direction until the signal is inverted to one of the binary signals when the signal indicates the other of the binary signals, and the head is accurately positioned at the reference position. A head positioning device for a disk device, characterized in that: