JPH07182811A - Servo light device - Google Patents

Abstract

(57) [Abstract] [Purpose] To realize an external positioning type servo write device that can suppress the amount of dust generated, suppress the variation in pitch between tracks, and suppress heat generation and thermal deformation of the magnetic disk device. The purpose is to [Structure] Push pin 8 in caulking hole 4a of gimbal 4
Is inserted and pressed to reliably position the magnetic head 3 fixed to the carriage 5. Further, the shafts 10 of the servo write device and the shaft 6 of the magnetic disk device are aligned by the adjuster 13 so that their central axes coincide with each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a servo write device for writing a servo pattern on a magnetic disk.

[0002]

2. Description of the Related Art With the recent demand for smaller size and larger capacity of magnetic disk devices, improvement in track density is becoming the most important issue in magnetic disk device development. Today, the surface servo system that positions the magnetic head based on the servo information recorded on the magnetic disk is the mainstream, and the so-called servo write technology, which is the servo information writing operation performed after the magnetic disk device is assembled. The improvement of the above is the key to downsizing the device shape and increasing the capacity of the magnetic disk device.

An example of a conventional servo write device is shown below. FIG. 4 and FIG. 5 are a perspective view and a main cross-sectional view of the configuration of an example of a conventional servo write device, respectively. In FIGS. 4 and 5, 1 is a housing of a magnetic disk device, 2 is a magnetic disk, 3 is a magnetic head, 4 is a gimbal that supports the magnetic head 3, 5 is a carriage that supports the gimbal 4 and is rotatable, and 6 Is a shaft serving as a rotation axis of the carriage 5,
Reference numeral 7 is a voice coil motor for driving the carriage 5, and the above are components of the magnetic disk device. In addition,
The bottom of the housing 1 is provided with an oval notch 21. In FIG. 4, 22 is the base plate of the servo light device,
Reference numeral 23 is a stopper, 24 is a spring stopper, and 25 is a push pin for pressing the carriage 5 of the magnetic disk device. In FIG. 5, 26 is a push arm to which the push pin 25 is fixed, 27 is a shaft that supports the push arm 26 to allow rotation, 28 is a voice coil motor that drives the push arm 26, and 29 is the push arm 2.
6 is a laser light reflecting mirror for measuring the displacement of 6 by a laser length measuring device (not shown).

The operation of the conventional servo write device will be described below with reference to FIGS. 4 and 5. First, the magnetic disk device is installed on the base plate 22, and the position of the magnetic disk device is regulated by the three stoppers 23.
It is pressed and fixed by. Push pin 2 at this time
5 passes through the notch 21 of the housing and projects to a position where it does not contact the carriage 5. The push arm 26 is supported by a shaft 27 through two bearings and driven by a voice coil motor 28. Push arm 26
The position of the reflecting mirror 29 attached to is accurately measured by the laser length-measuring device, and the push arm 26 is accurately positioned by controlling the current flowing to the voice coil motor 28 based on the data. At the start of servo writing, the push pin 25 moves the push arm 26 in the direction toward the inner peripheral side of the magnetic disk 2. The push pin 25 contacts the outer side surface of the carriage 5 and presses it in the inner peripheral direction. A direct current is applied to the voice coil motor 7 of the magnetic disk device so that the carriage 5 generates a force toward the outer peripheral side, and the carriage 5 and the push pin 25 are pressed against each other to reliably maintain the contact therebetween. By controlling the position of the push arm 26, the position of the magnetic head 3 is indirectly controlled. At the time of writing the servo pattern, the magnetic head 3 writes the servo pattern while moving the magnetic head 3 by 1 track or 1/2 track from the outermost circumference to the innermost circumference on the magnetic disk 2. At the end of the servo write, the push pin 25 is moved to the outer peripheral side until it is separated from the carriage 5, the direct current flowing in the voice coil motor 7 of the magnetic disk device is cut off, and the magnetic disk device is removed from the base plate 22.

[0005]

However, the length of the carriage 5 has been shortened due to the recent progress of miniaturization of the magnetic disk device, and in the configuration of the conventional servo write device, a push pin is provided on the carriage. It has become difficult to secure a space for contact, and it has been difficult to realize an ultra-small magnetic disk device. Further, the base material of the carriage 5 is an alloy mainly composed of aluminum or magnesium, and the surface hardness is low because it is die cast, and the surface is rough, so that dust is likely to be generated by rubbing at the contact portion with the push pin 25. However, the reliability of the magnetic disk device has been significantly reduced.

Further, when fixing the magnetic disk device, the side surface of the housing 1 of the magnetic disk device is pressed against the stopper 23 to perform positioning, so that the shaft 27 of the servo write device and the shaft 6 of the magnetic disk device are positioned. There was a non-negligible error on the central axis. Therefore, the rotation angle of the push arm 26 and the rotation angle of the carriage 5 do not match,
The track-to-track pitch recorded on the magnetic disk 2 causes a large deviation between the inner and outer circumferences.

Further, during the writing of the servo pattern, the voice coil motor 7 of the magnetic disk device keeps flowing a direct current, so that the voice coil motor 7 generates heat, and this heat generation causes thermal distortion in each part of the magnetic disk device. It was In order to suppress this heat generation, the current value needs to be lowered, but the torque constant of the voice coil motor 7 has also become smaller due to the miniaturization of the magnetic disk device, and as a result, the mutual pressing force with the push pin 25 decreases. The carriage 5 pushes the push pin 25 due to slight vibration.
There was a significant deviation in the position of the magnetic head 3 away from. That is, the occurrence of thermal distortion in the servo write or the deterioration of the positioning accuracy of the magnetic head deteriorates the quality of the servo pattern, which is an obstacle to the realization of high-speed access and high track density, which are important performances of the magnetic disk device.

Therefore, the present invention solves the above-mentioned conventional problems, and an object thereof is to provide a servo write device for realizing a small-sized, highly reliable, and high-performance magnetic disk device.

[0009]

In order to achieve the above object, the present invention has a supporting means for supporting a carriage by inserting a substantially cylindrical rod into a caulking hole of a gimbal, and a rotating means for rotating the carriage. And a holding means for holding the carriage by a substantially cylindrical rod and a holder, and an axis aligning means for making the rotation center axis of the carriage and the rotation center axis of the rotation means for rotating the carriage substantially coincide with each other. The shaft alignment means has an adjuster for making the shaft of the carriage and the shaft of the rotation means contact the V-shaped groove at the same time.

[0010]

According to the present invention, the amount of dust generated can be suppressed to a low level because the present invention abuts and presses the caulking hole of the gimbal. Further, since the central axes of the two shafts of the servo write device and the magnetic disk device are made to coincide with each other, it is possible to suppress variations in track pitch.
Further, by pressing the carriage from two directions, it is not necessary to supply a direct current to the voice coil motor of the magnetic disk device, and heat generation and thermal deformation due to heat generation can be suppressed.

[0011]

EXAMPLES An example of the present invention will be described below.
FIG. 1 is a perspective view showing the configuration of the servo light device of the present invention. In FIG. 1, reference numeral 1 is a housing of the magnetic disk device, 2 is a magnetic disk, 3 is a magnetic head, 4 is a gimbal for supporting the magnetic head 3, and 4 a is a caulking hole of the gimbal 4. 5 is a carriage, which is a gimbal caulking hole 4a
At, the gimbal 4 and the carriage 5 are fixed.
Reference numeral 6 is a shaft that serves as a rotation axis of the carriage 5, reference numeral 7 is a voice coil motor that drives the carriage 5, and the above are components of the magnetic disk device. Reference numeral 8 is a push pin that presses the carriage 5 to seek the magnetic head 3, and uses stainless steel as a material. Reference numeral 9 is a push arm that supports the push pin 8, 10 is a shaft that serves as a rotation axis of the push arm 9, 11 is a voice coil motor that drives the push arm 9, and 12 is the push arm 9
Of the laser beam for measuring the displacement of the disk by a laser length measuring device (not shown), 13 is an adjuster for aligning the central axes of the shaft 6 of the magnetic disk device and the shaft 10 of the servo write device, and 14 is a vertical movement A stage, 15 is a stopper that regulates and fixes the position of the housing 1, and 16 is a spring stopper that fixes the housing 1.

The operation will be described below. In FIG. 1, components 8 to 13 are fixed to the elevating stage 14 as one unit and can be vertically moved. The elevating stage 14 is positioned at the uppermost position in advance, and the magnetic disk device can be attached and detached. First, the housing 1 of the magnetic disk device is pressed against the stopper 15 to perform rough positioning. Next, the elevating stage 14 is lowered and fixed at a predetermined position. In this position, the push pin 8 is gimbal 4
The lowermost part of the adjuster 13 inserted in the caulking hole 4a is located below the uppermost part of the shaft 6 of the magnetic disk device. Here, the protruding portion of the shaft 6 of the magnetic disk device is brought into contact with the adjuster 13, and the housing 1 of the magnetic disk device is fixed by the pressing force of the spring stopper 16.

The operation of the adjuster 13 will be described with reference to FIG. FIG. 2 is a plan view showing the axial alignment operation of the adjuster 13 in the servo write device according to the embodiment of the present invention. The adjuster 13 has two planes arranged in a V-shape sandwiching a right angle, and these two surfaces are fixed in advance in positions where they abut on the shaft 10 of the servo light device.
Since the two shafts 6 and 10 have the same diameter, when the shafts 6 of the magnetic disk device come into contact with the two flat surface portions of the adjuster 13, the two shafts 6 and 10 are brought into contact.
The shaft 10 and the shaft 10 are completely overlapped with each other in FIG. Further, the adjuster 13 serves as a positioning reference when fixing the housing 1 together with the stopper 15, and it is not necessary to pursue the accuracy of the outer dimensions of the housing 1 with high accuracy.

Next, the operation during servo write will be described. The current flowing to the voice coil motor 11 of the servo write device is controlled so that the magnetic head 3 moves from the outermost circumference to the innermost circumference on the magnetic disk 2 by 1 track or 1/2 track. The push pin 8 comes into contact with the outer side surface of the carriage 5 and presses it toward the inner peripheral direction, and a direct current is applied to the voice coil motor 7 of the magnetic disk device so that the carriage 5 generates a force toward the outer peripheral side. The push pins 8 are pressed against each other to ensure contact between them. At this time, since the respective shafts 6 and 10 of the servo write device and the magnetic disk device are accurately aligned by the adjuster 13, the rotation angles of the push arm 9 and the carriage 5 are almost completely aligned. The amount of movement of the magnetic head 3 is actually converted by measuring the displacement of the reflecting mirror 12 of the laser beam mounted on the push arm 9 by a laser length measuring device.
And the actual displacement of the magnetic head 3 have an extremely high correlation, the fluctuation of the track pitch between the inner and outer circumferences is eliminated, and the servo pattern can be recorded with high accuracy.

Here, by making the caulking hole 4a of the gimbal 4 made of stainless steel having a high hardness and having a smooth surface to be pressed by the push pin 8, the generation of dust due to the rubbing of both can be eliminated. Therefore, the positioning accuracy of the magnetic head 3 can be kept high.

Next, another embodiment of the present invention will be described with reference to FIG. FIG. 3 is a sectional view showing the holding operation of the holder in the servo write device according to another embodiment of the present invention.
In this embodiment, a holder is added to the servo writer of the above-described embodiment, and the same operation is performed except for the holding operation of the carriage 5. In FIG. 3, 17 is a holder that holds the carriage 5 by pressing it from the direction opposite to the push pin 8, and 18 is a hinge that allows the holder 17 to rotate.
Reference numeral 19 is a pressing spring, and 20 is a hook for holding the holder 17. The holder 17 is retained on the hook 20 with the pressing spring 19 compressed most until the fixing of the magnetic disk device is completed. In this state, the holder 17
The carriage abutting portion is away from the push pin 8 and the outer diameter of the push pin 8 is smaller than the caulking hole 4a of the gimbal 4, so the carriage 5 is not fixed to the push arm 9. After the fixing of the magnetic disk device is completed, when the holder 17 is removed from the hook 20, the carriage contact portion of the holder 17 presses the carriage 5 together with the push pin 8 in both directions by the force of the pressing spring, and the carriage 5 is The push arm 9 is fixed in the seek direction. By using the holder 17, it is not necessary to apply a direct current to the voice coil motor 7 of the magnetic disk device, and heat generation and thermal deformation of the magnetic disk device can be suppressed. Further, it is suitable for an ultra-small magnetic disk device in which the torque generated by the voice coil motor is small.

[0017]

As is apparent from the above description, according to the present invention, since the push pin is brought into contact with the caulking hole of the gimbal and pressed to write the servo pattern, it is difficult for the conventional servo write device. It is possible to realize servo write of ultra-small magnetic disk unit. Further, since both the push pin and the caulking hole of the gimbal are made of stainless steel as the base material, the amount of dust generated can be kept low, and the reliability of the magnetic disk device is greatly improved. Further, since the center axes of the two shafts of the servo write device and the magnetic disk device are made to coincide with each other, it is possible to suppress the variation in the pitch between tracks, and further, by holding the carriage by the push pin and the holder, the voice coil motor of the magnetic disk device. Since it is not necessary to apply a direct current to the device, heat generation and thermal deformation due to heat generation can be suppressed, and high positioning accuracy against vibration can be maintained, which facilitates realization of a high-performance magnetic disk device. Thus, the effect of the present invention is extremely large.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration of a servo light device according to an embodiment of the present invention.

FIG. 2 is a plan view showing the axial alignment operation of the adjuster in the servo write device according to the embodiment of the present invention.

FIG. 3 is a sectional view showing a holding operation of a holder in a servo light device according to another embodiment of the present invention.

FIG. 4 is a perspective view showing the configuration of an example of a conventional servo light device.

FIG. 5 is a main cross-sectional view showing the configuration of an example of a conventional servo write device.

[Explanation of symbols]

 1 Case 2 Magnetic Disk 3 Magnetic Head 4 Gimbal 4a Caulking Hole 5 Carriage 6 Magnetic Disk Device Shaft 7 Magnetic Disk Device Voice Coil Motor 8 Push Pin 9 Push Arm 10 Servo Light Device Shaft 11 Servo Light Device Voice Coil Motor 12 Reflector 13 Adjuster 14 Lifting Stage 15 Stopper 16 Spring Stopper 17 Holder 18 Hinge 19 Pressing Spring 20 Hook

Claims (6)

[Claims] 1. A servo write device having a supporting means for supporting a carriage of a magnetic disk device and a rotating means for rotating the carriage, wherein the supporting means has a substantially cylindrical rod. Servo light device to do. 2. A servo write device according to claim 1, further comprising a support means for inserting a substantially cylindrical rod into a caulking hole of a gimbal attached to a carriage of the magnetic disk device. 3. A servo write device having a supporting means for supporting a carriage of a magnetic disk device and a rotating means for rotating the carriage, wherein the carriage is held by a substantially cylindrical rod and a holder. A servo light device having a holding means. 4. A servo write device having a supporting means for supporting a carriage of a magnetic disk device and a rotating means for rotating the carriage, wherein a rotation center shaft of the carriage and the carriage are rotated. A servo light device comprising axis alignment means for substantially matching the rotation center axis of the rotation means. 5. A shaft of a carriage of a magnetic disk device and a shaft of a rotating means for rotating the carriage have substantially the same diameter, and the shaft of the carriage and the shaft of the rotating means are in contact at the same time. The servo write device according to claim 4, wherein the axis aligning means has an adjuster in contact therewith. 6. The servo write device according to claim 5, wherein the adjuster has a V-shaped groove.