JP2598697B2 - Magnetic head tester - Google Patents

Description

The present invention relates to a magnetic head tester, and more particularly, to a magnetic head tester.
The present invention relates to a magnetic head tester that requires a short time to inspect a magnetic head used such as a hard magnetic disk.

2. Description of the Related Art Conventional magnetic head testers include a test device for measuring a flying height of a magnetic head, which is a physical characteristic, and a test device for measuring an electromagnetic conversion characteristic, which is an electrical characteristic. There are types.

Usually, the characteristics of the magnetic head are inspected by these two types of measuring devices. In general, first, the flying characteristics of the magnetic head are measured, and then the electromagnetic conversion characteristics of the acceptable products are measured.

[Problem to be Solved] Therefore, in order to test the magnetic head, it is necessary to mount the magnetic head on each of two test devices, and it takes time and effort to mount and remove the magnetic head.
It is necessary to manage the magnetic head with respect to one of the measurement results, and it takes a lot of time to test one magnetic head.

On the other hand, in recent years, hard magnetic disk devices have been demanded for higher density recording than before, and are required to ensure high reliability. Accuracy is also getting higher. Therefore, the overall throughput of the magnetic head inspection tends to decrease. For this reason, when different tests are performed by the two test devices as described above, it takes time to mount the magnetic head and to remove the magnetic head in this case, and furthermore, the influence of the mounting state on the test results. Which is also a factor that reduces the yield.

The present invention solves such problems of the prior art, and can measure head flying characteristics and electromagnetic conversion characteristics with a single test device, and can improve measurement efficiency. An object of the present invention is to provide a magnetic head tester.

[Means for Solving the Problems] The configuration of the magnetic head tester according to the present invention for achieving the above object includes a first disk for measuring the flying characteristics of the magnetic head and an electrical characteristic of the magnetic head. And a second disk for measuring a magnetic head is arranged in parallel with the first disk. A first carriage position on which a carriage on which a magnetic head is mounted is disposed opposite to the first disk for measuring a flying characteristic is determined by an electric characteristic. The carriage on which the magnetic head is mounted facing the second disk for measuring the
And a carriage on which a magnetic head is mounted, which is selectively positioned at the carriage position.

[Operation] As described above, the disk for measuring the flying height and the disk for measuring the electrical characteristics are juxtaposed and juxtaposed, and one carriage is conveyed by, for example, its conveyance line. Because they are commonly used,
It is no longer necessary to attach and detach the magnetic head to be tested for each measurement.Driving and stopping motors related to mechanisms such as the carriage in each measurement, and starting and controlling each test device and related circuits are eliminated. It is not necessary to carry out each of them independently, and the data of the flying characteristics and the electromagnetic conversion characteristics of the magnetic head can be easily obtained for the magnetic head which is being tested.

As a result, the time required to perform each measurement can be reduced, the head flying characteristics and the electromagnetic conversion characteristics can be measured in a short time with one test apparatus, and the measurement efficiency of the entire measurement process can be improved. .

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic view of an embodiment to which the magnetic head tester of the present invention is applied, and FIG. 2 is a detailed view of a platen portion thereof.

In FIG. 1, reference numeral 20 denotes a magnetic head tester, reference numeral 21 denotes a measurement mechanism unit, and reference numeral 22 denotes a measurement control / data processing unit, which includes a microprocessor, a memory, and the like.

Reference numeral 1 denotes a platen table provided in the measuring mechanism section 21. On the platen table 1, a glass disk 2 for measuring a floating characteristic is fixed to a spindle 3, as shown on the right side of the drawing. A magnetic disk 4 (hard disk) for measuring electromagnetic conversion characteristics is fixed to a spindle 5 as shown on the left side of the drawing. Here, the spindle 3 and the spindle 5 are connected to independent motors, respectively, and are independently driven at the time of each measurement in accordance with a control signal from the measurement control / data processing unit 22.

Reference numeral 23 shown by a dotted line denotes an optical system for measuring the flying height arranged on the upper side of the glass disk 2, which irradiates a laser beam or a normal light beam to receive reflected light, and receives the reflected light. The distance between the magnetic head 9 and the loaded magnetic head 9 is measured, the measurement result is converted into an electric signal, and transmitted to the measurement control / data processing unit 22.

Reference numeral 6 denotes a linear transport line disposed adjacent to the two disks so as to be parallel to each other, and is constituted by a transport mechanism such as a ball screw mechanism and an air cylinder. Connected to the member.

The carriage 7 includes an X table 7x and a Y table 7y provided on the X table 7x. When the carriage 7 is driven by the linear transport line 6, the X table 7x and the Y table 7y serve as the rotation centers of the two disks. Move in the X direction parallel to the passing line. Then, the Y table 7y placed on the X table 7x is driven in a direction perpendicular to the X table 7x to move in the Y direction perpendicular to the linear transport line 6 (crossing the two disks). , Radial movement).

Reference numeral 8 denotes a platen which is positioned at a precise position on the Y table 7y by a claw mechanism, a screw, or the like, and is detachably fixed thereto. As shown in FIG. The target magnetic head 9 is mounted. As can be seen from FIG. 2 showing this state, the magnetic head 9 is detachably fixed to the holder 10 on the platen 8.

The holder 10 includes a right-angle hook-shaped fixing member 11 having two sides in a right angle direction serving as a guide and a stopper, and two positioning pins 12 and 12 provided therein. By moving back and forth in the direction of 45 degrees, the rectangular member 9a at the base of the magnetic head 9 is brought into contact with each side at a right angle, and abutting in the XY direction is performed, so that the two positioning pins 12, 1
Positioning is fixed between the two. Note that positioning pin 1
The magnetic heads 2 and 12 are positioned in a more accurate position on the platen 8 by being fitted into two positioning holes provided in the rectangular member 9a at the base of the magnetic head 9, respectively.

Reference numeral 13 denotes a paddle, which has contact stripes 13a and 13b with which the probe contacts, and the lead wire 9b of the magnetic head 9 is connected to the contact stripes 13a and 13b. This is, for example, a small ceramic substrate, which is mounted on a box-shaped paddle guide 14 having an open end provided on the platen 8 and having rotating claws 15, 15 from both sides.
It is detachably fixed by the rotation of.

Therefore, when the magnetic head 9 to be tested is mounted on the holder 10, the lead wire 9b of the magnetic head 9 is connected to the paddle 13, so that the probe 16 is connected to the contact stripes 13a, 13b provided on the paddle 13. 1 (see FIG. 1) is contacted and connected to a read / write amplifier (R / W amplifier) 19a arranged on the base table 1. As a result, the magnetic head 9 is connected to the electric circuit of the measurement control / data processing unit 22 disposed below the base table 1 via the read / write amplifier 19a.

17a, 17b, 17c, and 17d are position detection sensors such as a photo interrupter and a photo sensor, respectively. When the carriage 7 is driven and moved by the linear transport line 6, the position of the carriage 7 is transferred to the carriage 7. By detecting the provided detecting pieces, holes, and the like, it is detected that they are at the positioning reference position, and their detection outputs are sent to the measurement control / data processing unit 22.

Therefore, the carriage 7 is disposed so as to face the center of the glass disk 2 so that the locus of the access process of the magnetic head 9 mounted on the platen 8 of the XY table 7 corresponds to the center of the glass disk 2 by detecting the positions of the position detection sensors 17a and 17b. And the movement is stopped. Note that a stopper or the like may be provided corresponding to this position. This position is the position of the carriage 7 indicated by a dashed line corresponding to the glass disk 2, and is the positioning position of the carriage with respect to the glass disk 2 in the flying characteristic measurement.

In addition, the carriage 7 is disposed so as to face the center of the magnetic disk 4 so that the locus of the access process of the magnetic head 9 corresponds to the center of the magnetic disk 4 by the position detection of the position detection sensors 17c and 17d, and the movement is stopped. Note that a stopper or the like may be provided corresponding to this position. This position is the position of the carriage 7 indicated by a dashed line corresponding to the magnetic disk 4, and is the position of the carriage relative to the magnetic disk 4 in the measurement of electromagnetic conversion characteristics.

18 and 19 are glass disk 2 and magnetic disk 4 respectively
The head loading mechanism for the magnetic head 9 provided in correspondence with the above. The read / write amplifier 19a for amplifying the electric signal from the magnetic head 9 is provided on the magnetic disk 9 side as described above. It is arranged adjacent to the mechanism 19.

Next, the operation will be described.
Are usually arranged on a pallet or the like and are placed separately from the magnetic head tester 20. One of them is first mounted on the holder 10 of the platen 8 and mounted. The platen 8 on which the magnetic head 9 is mounted is positioned at a predetermined position set on the Y table 7y of the carriage 7 and mounted on the carriage 7. If the magnetic head 9 can be replaced by making the platen 8 an independent unit as described above, even if the shape and form of the magnetic head 9 are changed, the platen 8 can be replaced.
It is only necessary to change the mounting relationship between the device and the magnetic head 9, and no modification on the device side is required.

The carriage 7 on which the platen 8 is mounted is in an initial state (initial position) before measurement, as shown by a solid line in FIG.
It is located between the glass disk 2 and the magnetic disk 4. This is almost at the center of the transport path of the linear transport line 6. Therefore, the measurement control / data processing unit 22 first
The linear transport line 6 is activated to position the carriage 7 in the flying height measurement system. In this positioning in this case, first, the linear transport line 6 is driven according to a control signal from the measurement control / data processing unit 22, the carriage 7 moves to the glass disk 2 side, and the position detection sensor 17a detects the position. Is positioned at the X direction position which coincides with the center of the glass disk 2, and is then positioned at the reference position in the Y direction by the position detection of the position detection sensor 17b. And
This position is a regular position where the carriage is arranged facing the glass disk 2 as a flying characteristic measuring device. The position detection is performed by the measurement control / data processing unit 22 receiving signals from the position detection sensors 17a, 17b, 17c, and 17d, for example, by determining whether these signals are in the “ON” state. This is done by making a determination.

Next, the Y table 7y of the carriage 7 is driven by a control signal from the measurement control / data processing unit 22 to move the magnetic head 9 toward the spindle 3, which is the center of the glass disk 2. Then, the magnetic head 9 is loaded on the glass disk 2 by the head loading mechanism 18, and the glass disk 2 is driven to rotate. Here, the magnetic head 9 flies. Note that this is an example of a contact start / stop, and the glass disk 2 may be rotated before head loading.

Next, the Y table 7y is measured by the measurement control / data processing unit 22.
Is controlled, and the magnetic head 9 moves to a predetermined measurement point which is a light irradiation point of the optical system 23 for measuring the flying height. At this position, the flying height is measured by the flying height measuring optical system 23, and the measurement is performed by the measurement control / data processing unit.
22 are stored in the memory corresponding to the data of the magnetic head. If the flying height measurement results in a failure, the platen 8 is removed from the carriage 7, the magnetic head 9 is removed from the platen, and the magnetic head 9 to be tested next is removed.
Is mounted on the platen 8, and the next magnetic head test is performed in the same manner as described above.

When the measurement of the flying height is completed, the carriage 7 returns to the initial position, which is the original reference position. Then, the process proceeds to the measurement of the electromagnetic conversion characteristics. First, the linear transport line 6 is driven according to a control signal from the measurement control / data processing unit 22, the carriage 7 moves to the magnetic disk 4 side, and the position of the magnetic disk 4 is detected by the position detection sensor 17c. The carriage 7 is positioned at a position in the X direction that coincides with the center of the position, and is further positioned at a reference position in the Y direction by detecting the position of the position detection sensor 17d. Then, this position is a regular position where the carriage is arranged so as to face the magnetic disk 4 as the electromagnetic conversion characteristic measuring device.

Next, the Y table 7y of the carriage 7 is driven by a control signal from the measurement control / data processing unit 22 to move the magnetic head 9 toward the spindle 5, which is the center of the magnetic disk 4. Then, the magnetic head 9 is loaded on the magnetic disk 4 by the head loading mechanism 19, and the magnetic disk 4 is driven to rotate. This is also a contact
This is a start / stop case. Next, similarly to the above, the Y table 7y is controlled by the measurement control / data processing section 22, and the magnetic head 9 is moved to a predetermined track position for measuring the electrical characteristics. W) The test is performed.

In the R / W test, the probe 16 comes into contact with the contact provided on the paddle with the magnetic head 9 positioned at a predetermined track position, and the electrical output of the magnetic head 9 is changed to the paddle 13, the probe 16, and the lead. A signal is sent to the measurement control / data processing unit 22 via the write amplifier 19a, and the signal is sent to the measurement control / data processing unit 22 for analysis.The data is analyzed by the data processing unit 22 in the same manner as the measurement of the flying height. This is performed by storing the data in a memory corresponding to the data. As in the case of the flying height measurement, if the result of the measurement of the electromagnetic conversion characteristics is unacceptable, the platen 8 is removed from the carriage 7 and
The magnetic head 9 is removed from the platen, the magnetic head 9 to be tested next is mounted on the platen 8, and the next magnetic head test is performed in the same manner as described above.

When the measurement of the flying height and the measurement of the electromagnetic conversion characteristics are completed in this way, the linear transport line 6 is driven, and the carriage 7 returns to its initial position, that is, the center position, and ends the measurement. Then, the platen 8 is removed at this position, the magnetic head 9 of the platen 8 for which the test has been completed is removed, and the magnetic head to be tested next is attached to the platen 8.

As described above, in the embodiment, the glass disk and the magnetic disk are connected by a linear transport line. However, this is not necessarily a linear transport line. In short, any transport mechanism may be used as long as it is a mechanism for transporting one carriage on which the magnetic head to be tested is mounted so that it can be positioned at the measurement position of the glass disk and the measurement position of the magnetic disk.

Although a glass disk is used as a disk for measuring the flying characteristics, the disk is not limited to the glass disk as long as it is a disk used for measuring the flying height.

In the embodiment, the trajectory of the access process of the magnetic head 9 coincides with the center of each disk. However, without doing so, for example, the access direction of the magnetic head may be arranged at right angles. .

Further, in the embodiment, each device is placed on the surface plate table, but this need not necessarily be on the surface plate table.

[Effects of the Invention] As can be understood from the above description, in the present invention, a disk for measuring the flying height and a disk for measuring the electrical characteristics are juxtaposed and juxtaposed, and one carriage is mounted. The common use eliminates the need to attach and detach the magnetic head to be tested for each measurement, and drives and stops the motors related to the carriage and other mechanisms in each measurement, as well as each test device and There is no need to independently start and control the related circuits,
The respective data of the flying characteristics and the electromagnetic conversion characteristics of the magnetic head can be easily obtained for the magnetic head which is being tested.

As a result, the time required to perform each measurement can be reduced, the head flying characteristics and the electromagnetic conversion characteristics can be measured in a short time with one test apparatus, and the measurement efficiency of the entire measurement process can be improved. .

[Brief description of the drawings]

FIG. 1 is a schematic view of an embodiment to which a magnetic head tester of the present invention is applied, and FIG. 2 is a detailed view of a platen portion thereof. Reference Signs List 1 ... Stable table, 2 ... Glass disk, 3,5 ... Spindle, 4 ... Magnetic disk, 6 ... Linear transfer line, 7 ... Carriage, 7x ... X table, 7y ... Table, 8 ... platen, 9 ... magnetic head, 10 ... holder, 11 ... fixing member, 12 ... positioning pin, 13 ... paddle.

Claims (1)

(57) [Claims] A first disk for measuring the flying characteristics of a magnetic head and a second disk for measuring the electrical characteristics of the magnetic head are juxtaposed to measure the flying characteristics. A carriage on which a magnetic head is mounted facing the first disk is arranged, and a carriage on which a magnetic head is mounted is arranged facing the second disk in order to measure a first carriage position and electrical characteristics. A magnetic head tester, comprising: a carriage on which the magnetic head is mounted, the carriage being selectively positioned at a second carriage position.