JPH03192586A - Magnetic head and its manufacturing - Google Patents

Abstract

PURPOSE:To reduce the dispersion of the floating height of a head by measuring the floating height of a head slider of a magnetic head, applying thermal displacement to a gimbal spring or a spring arm based upon the measured value to adjust the floating posture or floating height. CONSTITUTION:A glass disk is rotated to float the head slider 1, the floating heights of right and left rails are measured by a known method using laser beams and the difference between both the measured values is calculated. The change thetaR of an inclination angle thetaR1 in the slider direction which has been previously found out in accordance with the sort of a magnetic head is found out from the relation of difference of the changing variables thetaR so that the difference goes '0' and irradiating conditions, i.e. irradiating time, irradiating intensity and irradiating positions such as 9a to 9d are determined from the relation between the previously found thetaR and thermal displacement due to laser beams is applied to the gimbal spring 2. Similarly, the inclination angle thetap in the pitch direction can be adjusted and the minimum floating height of the outflow end of a slider 1 can be optimized.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a magnetic head and a method for manufacturing the same, and particularly to a magnetic head suitable for easily and highly accurately adjusting the flying height of a magnetic head for a magnetic disk device. The present invention relates to a magnetic head and its manufacturing method.

[Prior Art] Normally, a magnetic head for a magnetic disk device flies above a magnetic disk that is rotating at high speed while maintaining a minute interval.
Reading/writing information on the magnetic disk. Recently,
The flying height of this magnetic head is becoming increasingly narrower as the recording density of magnetic disk devices increases, and in order to avoid collisions between the magnetic disk and the magnetic head, it is necessary to stabilize the flying height of the head slider. This has become an important technical issue.

Factors causing variations in the flying height of the head slider can be roughly divided into two types: variations in the flying height of a single head due to manufacturing variations, and dynamic variations in the flying height during operation of the magnetic disk device. In the former case, variations in the flying height of individual heads due to manufacturing variations are caused by the accuracy and assembly precision of each component such as the magnetic head slider and head support spring. Conventionally, reducing flying height variations by improving the accuracy of these parts has been This was the main method.

Additionally, as a related technique, Japanese Patent Publication No. 60-32908 discloses a method of irradiating a slider surface with visible light, measuring the tilt angle from the reflected light, and controlling the tilt angle by bending a gimbal or support arm. has been done. In addition, Japanese Patent Application Laid-open No. 177692/1983 discloses that by inspecting the flying height balance due to manufacturing variations using a camera, etc., and adjusting the angle of the gimbal that supports the head in accordance with the amount of unbalance (tilt), A method of adjusting flying height balance is disclosed.

[Problems to be Solved by the Invention] As mentioned above, as the flying height of the head slider becomes narrower, it is required to reduce the variation in the flying height of the head slider due to manufacturing variations. There is a limit to the improvement in terms of productivity, cost, etc., and if things continue as they are, there is a problem that many defective products will be produced that do not satisfy the specification conditions required when inspecting the flying height.

Furthermore, the invention disclosed in Japanese Patent Publication No. 60-32908 is for adjusting the slider face angle within the specification range, but not for adjusting the flying height. Also, JP-A-61
The invention disclosed in Japanese Patent No. 177692 adjusts only the flying balance by adjusting the gimbal angle, and has a problem in that the entire flying height cannot be adjusted.

Furthermore, the inventions disclosed in Japanese Patent Publication No. 60-32908 and Japanese Patent Application Laid-open No. 61-177692 both use a head support gimbal spring to provide plastic deformation as a means of controlling to correct the head tilt angle. However, it does not take into account the return phenomenon (springback) of the support spring that occurs when the tilt angle of the head spring is corrected, and as a result, the tilt angle changes over time and the flying height changes. There is a problem with this. Furthermore, no consideration is given to automating the work from measuring the flying height of the head to adjusting the tilt angle to perform the adjustment work efficiently.

The present invention overcomes the problems of the above-mentioned conventional techniques and provides a magnetic throat and a method for manufacturing the same, which can change the inclination angle of a head support spring and obtain a head with small flying height variations. It is an object.

[Means for Solving the Problems] The method for manufacturing a magnetic head of the present invention involves making the magnetic head levitate by rotating a disk, measuring the flying height of the magnetic head, the throat, and the throat slider. Based on this, thermal displacement is applied to the gimbal spring or spring arm to adjust the flying attitude and flying height.

Here, the above-mentioned flying height measurement is performed on the flying height of the right rail and left rail of the henode slider of the magnetic head in the flying state and the flying height of the airflow outflow end of the head slider.
Further, the thermal displacement is performed by laser irradiation.

Further, in the magnetic head of the present invention, in a floating magnetic head composed of a gimbal spring, a spring arm, and a core slider, a polar thermal displacement is applied to the gimbal spring or the spring arm to adjust the inclination angle of the head slider. It is characterized by

[Function] According to the present invention, the flying height of the magnetic head flying by the rotation of the disk is measured, and the extreme parts of the gimbal spring or spring arm are heated based on the measured flying height. . This changes the inclination of the gimbal spring and spring arm, producing a magnetic head with an optimal flying posture.

To explain in more detail, it has been known that there is a certain relationship between the flying height of the head slider and the tilt angle of the gimbal spring, and this relationship can be divided into the tilt in the roll direction and the tilt in the pitch direction. That is, when adjusting the balance of the flying height of the slider outflow end, the tilt angle of the slider in the roll direction is relevant, and when adjusting the minimum flying height of the slider trailing end, the tilt angle of the slider in the pitch direction is relevant. Therefore, in order to adjust the head flying height, the magnetic head facing the disk is made to fly by rotating the disk, and the flying height of the left rail and right rail of the head slider (flying balance) and the flying height of the airflow outflow end are adjusted. measure quantity. Then, each of the measured flying heights is applied to the relationship between the flying balance of the head slider, the flying height of the airflow outflow end, and the corresponding tilt direction and amount of the gimbal spring, which have been determined in advance, and the deviation is calculated from the above. Calculate the amount of tilt angle adjustment of the gimbal spring in the roll direction and pitch direction.

The gimbal spring has a structure in which it has a degree of freedom in tilt angle in the roll and pitch directions due to dimples, so the tilt angle can be changed by applying thermal displacement to the gimbal spring. Therefore, in order to apply a thermal displacement corresponding to the gimbal spring tilt angle adjustment amount using a laser, the laser irradiation position corresponding to the tilt angle adjustment direction and the laser irradiation conditions (number of irradiation points) corresponding to the adjustment amount are set.

Determine the irradiation time and irradiation intensity) and irradiate. As a result, the gimbal spring part deforms due to the thermal displacement of the laser beam, changing the tilt angle, making it possible to adjust not only the flying height balance but also the minimum flying height.

Furthermore, the thermal deformation of the gimbal spring can be completed in a short time at high temperatures, allowing efficient adjustment work.

Further, according to the present invention, since springback of the spring does not occur, it is possible to eliminate changes in the flying height over time.

[Examples] The present invention will be described in more detail below with reference to Examples shown in the attached drawings.

FIG. 1(a) shows a position 9a on the gimbal spring 2 attached to the spring arm 4 for the purpose of giving the head slider 1 an appropriate flying balance by the method of the present invention.
FIG. 9 is a top view showing a state in which thermal displacement is applied to parts 9b, 9c, and 9d by laser irradiation.

The flying balance of the head slider 1 can be optimized by adjusting the slider direction inclination angle θ8 shown in FIG. 1(b). Here, FIG. 1(b) shows the first
FIG. 2 is a side view of the magnetic head shown in FIG.

Next, a method of providing proper flying balance to the above-mentioned head slider 1 will be explained. Figure 2 is similar to Figure 1 (b
) is a side view of the magnetic head shown in FIG. 1(a) when viewed from the direction of arrow A, and shows a state in which the magnetic head is floating on a glass disk 3. In FIG. 2, the head slider 1 is floated by the rotation of the glass disk 3, and the flying height H u @ of the left rail 1a and the flying height Hl of the right rail 1b are measured. And (H, u, -H,,;)
seek. Here, the measurement of the flying height Hout and H is as follows.
This is performed by a known method H using laser light. Next, as shown in FIG.
. From the relationship between and (H, u, H+-), (H05H1-)
Find the amount of change Δθ6 such that Δθ6 becomes O, and calculate this amount of change Δθ. The gimbal spring is machined with a laser so that the adjustment amount is applied to the gimbal spring. At this time, as shown in FIG. 4, the laser irradiation conditions are determined from the relationship between the amount of change Δθ determined in advance and the laser irradiation conditions. Here, the laser irradiation conditions include, for example, laser irradiation time, irradiation intensity, and irradiation position. That is, the laser irradiation positions 9a, 9b, 9c, and 9d shown in FIG. 1(a) are determined at this time.

Next, the adjustment of the minimum flying height at the outflow end of the airflow will be explained. FIG. 5(a) is a top view showing a state where positions 9e and 9f of the gimbal spring 2 are irradiated with a laser to give thermal displacement for the purpose of adjusting the minimum flying height of the outflow end according to the method of the present invention. . When adjusting the minimum flying height of the outflow end, the inclination angle θ in the pitch direction is adjusted as shown in FIG. 5(b). Here, FIG. 5(b) is a side view of the magnetic head shown in FIG. 5(a) viewed from the direction of arrow B.

Next, a method for optimizing the minimum flying height of the outflow end of the head slider 1 described above will be explained.

6 is a side view of the magnetic head shown in FIG. 5(a) seen from the direction of arrow B, similar to FIG. 5(b), and shows the magnetic head floating on the glass disk 3. It shows. In FIG. 6, the head slider 1 is floated by rotating the glass disk 3, and the outflow end flying height H is measured. and,
The difference (H-Hp) between the flying height and the target value H9 is determined. Then, as shown in FIG. 7, the amount of change Δθ is determined from the relationship between the tilt angle θ in the pitch direction determined in advance and (HH,). Furthermore, the gimbal spring 2 is processed with a laser so that the amount of change Δθ is applied to the gimbal spring 2 as an adjustment amount. At this time, as shown in Figure 8,
The laser irradiation conditions are determined from the relationship between the amount of change Δθ8 determined in advance and the laser irradiation conditions. As described above, the laser irradiation conditions include, for example, laser irradiation time, irradiation intensity, and irradiation position. That is, FIG. 5(a)
Laser irradiation positions 9e and 9f shown in are determined at this time.

The quality can be ensured by measuring the flying height again after adjusting the slider direction inclination angle θ6 and the pitch direction inclination angle θ.

In addition, in the above-described embodiment, FIGS. 3, 4, and 7
The relationships shown in Figures 8 and 8 must be determined in advance for each model.

In the above explanation, the gimbal spring 2 was adjusted by laser irradiation, but the present invention is not limited to this.
For example, heating using electromagnetic waves can also be used. Further, the heating position is not limited to the gimbal spring, but may also be the spring arm 4.

According to this embodiment, since the flying balance and the outflow end flying height are adjusted by laser irradiation or the like, the flying height does not change over time. Furthermore, according to this embodiment, by simply determining the relationships shown in FIGS. 3, 4, 7, and 8 for each model,
Adjustment work can be performed efficiently.

[Effects of the Invention] According to the present invention, it is possible to reduce variations in volume caused by variations in manufacturing without increasing the accuracy of parts or assembly, and as a result, the levitation balance can be optimized. The minimum value of the head flying height can be optimized, and stable flying of the magnetic head can be realized. Therefore, it is possible to contribute to higher density recording and higher reliability of magnetic disk devices.

Further, according to the present invention, since the gimbal spring is adjusted by heating the gimbal spring at an extremely high temperature, the head inclination angle does not change over time. Furthermore, since the deformation process is completed instantly, a series of operations from measuring the flying height to adjustment operations can be performed efficiently.

[Brief explanation of drawings]

FIG. 1(a) is a top view showing a state in which a part of the gimbal spring is irradiated with a laser to give thermal displacement in order to give the head slider an appropriate flying balance according to the present invention, and FIG. 1(b)
) is a side view of the magnetic head shown in Fig. 1(a) as seen from the direction of arrow A, and Fig. 2 is a side view of the magnetic head floating above the glass substrate in the direction of arrow A shown in Fig. 1(a). Figure 3 is a side view of the slider direction tilt angle, which is determined according to the magnetic head model, and the amount of change Δθ8 and (H, , u, -H).
3°); FIG. 4 is a diagram showing the relationship between the amount of change Δθ1 determined in advance and the laser irradiation conditions;
FIG. 5(a) is a top view showing a state in which a part of the gimbal spring is irradiated with a laser to cause thermal displacement for the purpose of adjusting the minimum flying height of the airflow outflow end of the head slider according to the method of the present invention; Figure (b) is a side view of the magnetic head shown in Figure 5 (a) as seen from the direction of arrow B, and Figure 6 is a side view of the magnetic head floating above the glass substrate as shown by the arrow in Figure 5 (a). A side view seen from the direction of B, Fig. 7 shows the pitch direction inclination angle θ,
FIG. 8 is a diagram showing the relationship between the amount of change Δθ determined in advance and the laser irradiation conditions. 1... Head slider, 2... Gimbal spring, 3...
...Glass disc, 4...Spring arm, 9a, 9
b. 9c, 9d, 9e, 9f--Laser irradiation position.

Claims (1)

[Claims] 1. The magnetic head is levitated by rotation of a disc, and the flying height of the right rail and left rail of the head slider of the magnetic head in the flying state and the flying height of the airflow outflow end of the head slider are measured. A method for manufacturing a magnetic head, characterized in that the flying attitude and flying height are adjusted by applying thermal displacement to a gimbal spring or a spring arm based on each measured flying height. 2. The method of manufacturing a magnetic head according to claim 1, wherein the thermal displacement is performed by laser irradiation. 3. A floating magnetic head composed of a gimbal spring, a spring arm, and a core slider, characterized in that the gimbal spring or spring arm is subjected to extreme thermal displacement to adjust the tilt angle of the head slider. magnetic head.