JPS59221870A - Floating slider - Google Patents

Abstract

PURPOSE:To obtain minute floating distance stably by providing a groove whose air flowing-in end is opened along the longitudinal direction of a floating face and flowing-out end is closed. CONSTITUTION:A groove 14 that is opened in an air flowing-in end tapered face 13 and is closed in the opposite side which is an air flowing-out end 15 along the longitudinal direction of a floating face 12 of a floating slider. Accordingly, the pressure distribution on the floating face 12 becomes a curve Y, that is, high at the flowing-in end B, relatively low at the flowing-out end C, and at the intermediate part pressure is reduced. Therefore, the air film rigidity in the direction of pitching becomes high, and the danger of contact etc. is reduced remarkably, and the stable floating is obtained. The total of pressure generated as a whole is reduced without marring stability and the floating distance can be reduced than before.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a floating slider that holds a magnetic head, and particularly to the structure of the floating surface.

2. Description of the Related Art Magnetic storage devices use a floating slider that floats above a recording medium through a small gap by using the fluid force of the airflow created by the traveling of the recording medium.

Figure 1 is a plan view of the conventional floating slider, and Figure 2 is a plan view of the conventional floating slider.
The figure is a side view of the floating slider shown in FIG. 1. In each figure, (1) is a floating slider, and floating surfaces (2) extending in the direction of movement of the recording medium are formed on both sides of the slider. A tapered surface (3) is formed at the air inflow end of the floating surface (2). (4) is the air inflow end of the floating slider (1), (
5) is the air outflow end of the floating slider (1), and (6) is the load spring. The floating surface (2) is formed on the surface of the floating slider (1) facing the recording medium, and generates positive pressure by airflow generated by the movement of the recording medium. The hydrodynamic force of the air flow will balance 7 the load being applied elastically by the load spring (6). In order to achieve high-density, large-capacity recording in magnetic storage devices and increase the reliability of data processing, the separation distance between the magnetic head and the recording medium, or the flying distance, must be kept as small and stable as possible, and the magnetic head It is important to improve electromagnetic conversion performance.

In such a floating slider (1), in order to minimize the flying distance, the spring force of the load spring (6) can be increased, or the width W of the floating surface (2) that generates positive pressure can be decreased to reduce the air flow. There are methods such as reducing the fluid force caused by the flow. However, although it is physically possible to increase the spring force of the load spring (6), the pressure per unit area on the floating surface (2) increases. For this reason, in the case of a floating slider used in the contact start/stop method, the contact pressure between the floating surface (2) and the recording medium surface increases, increasing the probability of head crash when starting or stopping the recording medium. turn into. On the other hand, when the area of the floating surface (2) is made smaller, similar results occur; in particular, reducing the width W of the floating surface reduces the horizontal beam coefficient, which lowers the rigidity of the air film and increases the slider's This will worsen the stability of floating. As described above, in the conventional floating slider, it is difficult to stably obtain a small flying distance.

The present invention was made in order to eliminate the drawbacks of the conventional ones as described above, and by forming a groove in the floating surface with the air inflow end side open along the extension direction, a minute floating distance can be stabilized. In addition, it is an object of the present invention to provide a floating slider whose flying distance is reduced by a small amount even if the tilt (hereinafter referred to as yaw angle) of the floating slider's orientation with respect to the air inflow direction is reduced. Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 3 is a plan view showing an embodiment of the floating slider according to the present invention, and FIG. 4 is a sectional view taken along line AA in FIG. 3. Figure 3,
In FIG. 4, (11) is a floating slider, and (12) is a floating surface extending on both sides of the floating slider (11) in the moving direction of the recording medium, and facing the recording medium.

(13) is a tapered surface provided at the air inflow end of the floating surface (12), (14) is a groove provided in the floating surface (12),
It extends in the longitudinal direction of the floating surface (12). The above groove (14)
is open at the air inflow end on the Taber surface (13), and the opposite side is closed to form the air outflow end terminal point (15). Note that the bottom surface (16) is parallel to the floating surface (12).

Here, when the movement of the recording medium generates an air flow in the direction shown by arrow S in FIG.
Air flows into the groove (14) from 3), and the air flows into the groove (14).
Since three sides of the groove (14) are closed by the floating surface 12), there is no escape, and the air outlet end of the groove (14) (
In step 15), a rapidly rising positive pressure fluid force is generated. Therefore, if this air outflow end side terminal point (15) is provided closer to the air outflow end (5) of the floating slider (11), the positive pressure at the air outflow end will become very high.
The stiffness of the air film increases, allowing for stable levitation. On the other hand, also in the air inflow end tapered surface (13), by optimally setting the inclination of the tapered surface, the area of the tapered surface, etc., it is possible to further increase the positive pressure fluid force on the air inflow side compared to the conventional example. These conditions are shown in FIG. The figure shows the pressure distribution of the fluid force generated on the floating surface of each floating slider (1) and (11), where curve X is the pressure distribution in the conventional floating slider (1), and curve Y is the pressure distribution in the floating slider (1) of the conventional example. This is the pressure distribution on the floating slider (11) due to As can be seen from the figure, in the floating slider (11) according to the present invention, the positive pressure rapidly increases at the peak points Yl and Y at the air inflow end point B and the air outflow end point C.
2 are provided. On the other hand, between point B and point 0 is a floating surface (12
) is divided into two by the groove (14) and the area decreases, and at the same time, the width of the divided floating surface becomes narrower, so the horizontal beam coefficient decreases, and the pressure generated between points B and C is equal to the curve X. This is significantly lower than the pressure of the conventional example shown in . In this way, in the present invention, the pressure due to the fluid force at the center of the floating surface (12) is further reduced, and the reduced pressure is applied to the air inflow end.

It is concentrated at both ends of the outflow end. Viewed from the entire floating slider, the generated fluid force is concentrated at the four corners, which is an ideal condition for stably floating the floating slider (11), and is especially true for the conventional floating slider (11). Compared to 1), the rigidity in the pitching direction is significantly higher.

This type of floating slider (11) usually floats slightly above the recording medium, and the flying distance is the largest at the air inlet end and the smallest at the air outlet end.

The magnetic head is normally mounted at the air outflow end where the flying distance is small.

By the way, when the flying distance is very small, such as 0.5 m or less, the air on the floating slider may be affected by a slight disturbance such as unevenness on the surface of the recording medium or external vibration. The outflow end will come into contact with the surface of the recording medium, and in the worst case, there is an increased probability that this will lead to hendokrasoch. However, according to the present invention, the rigidity in the pitching direction is increased, and at the same time, the air film rigidity is particularly high near the air outlet end where contact accidents are likely to occur, so the risk of accidents is greatly reduced and stable floating is achieved. can be obtained. In addition, since the pressure increased at point B and point 0 at both ends is decreased between point B and point 0, the total pressure generated in the entire floating slider (11) is the total pressure in the conventional example. Since the overall positive pressure fluid force can be reduced without compromising stability, the flying distance can be set smaller than before.

Furthermore, according to the present invention, yaw angle characteristics can also be improved. The situation will be explained using FIG. 6. In FIG. 6, when the direction θ between the center line of the floating slider and the air inflow direction, that is, the yaw angle, is zero, the fluid force F generated on the floating surface (2) of the floating slider (11) is calculated using the approximate formula (1) ) is calculated.

Here, αp is the horizontal beam coefficient, μ is the viscosity coefficient of air, U is the velocity of the air flow, W is the floating surface width, LO is the floating surface length, and h is the flying distance. On the other hand, when the yaw angle θ has a finite value, the effective floating surface length is Ll as shown in the figure, and by substituting this into approximate equation (1), the fluid force (or floating blade) is When calculating F+, the floating surface length Ll is calculated for the fluid force F1.
acts as a square, so Fl will be significantly reduced compared to the case of θ-〇. The fact that the flying blade F1 becomes smaller means that the flying distance of the floating slider becomes significantly smaller than when the flying distance is θ-0. When a low reactuator method is adopted as a method for accessing the magnetic head to the required track, the yaw angle is constantly changing, and the flying distance changes each time. The amount of change in the flying distance can reach 30 to 40% compared to when the yaw angle is zero, especially in recent years when flying distance is set in a minute area where the overall flying distance is less than 0.5 μm. With a slider, the amount of change in flying distance due to the amount of change in yaw angle tends to increase.

Since the design value of the floating slider is determined by the lower limit of the flying distance, in order to minimize the overall flying distance, it is preferable to minimize the amount of change in the flying distance due to changes in the yaw angle. In the conventional example, a floating surface (
2), the fluid force F is the length of the floating surface Lo,
The fluid force generated in the groove (14) of the present invention, which is directly and significantly influenced by The amount of air does not change significantly even when the yaw angle has a finite value, and the amount of change in flying distance is small compared to the conventional example, resulting in a floating slider with excellent yaw angle characteristics.

Note that FIG. 7 shows another embodiment of the floating slider according to the present invention, and this figure corresponds to the sectional view taken along line AA shown in FIG. 3G. In this case, the groove (1) formed in the floating surface (12)
4) has an inclined surface where the bottom surface is deep at the air inflow end (l[11) and shallow at the air outflow end. The same effect as in the embodiment described above can be obtained.Furthermore, the present invention is also applicable to the end point (15) of the groove (14) as shown in FIG.
Even if the side is formed into a bay dog, or the width of the groove (14) shown in No. 9 TyU is made gradually narrower toward the air outlet end, or the width of the groove (14) shown in FIG. Even if a plurality of grooves (14) are provided on the floating surface (12) of 1 (-), or the cross-sectional shape of the groove (14) is made into an inverted trapezoidal shape as shown in Figure 11, the above embodiment can be achieved. Of course, similar effects can be achieved.

As is clear from the above explanation, the present invention makes it possible to provide a floating slider that can set the flying distance more minutely, can float stably, and has excellent yaw angle characteristics. Become.

[Brief explanation of drawings]

Figure 1 is a plan view showing an example of a conventional floating slider;
The figures are a side view of the conventional floating slider shown in Fig. 1, and a side view of the conventional floating slider shown in Fig. 3.
4 is a cross-sectional side view of the floating slider according to the present invention shown in FIG. 3; and FIG. 5 is a plan view showing a floating slider according to an embodiment of the present invention; FIG. FIG. 6 is a diagram showing the pressure distribution, FIG. 6 is a diagram explaining the yaw angle θ between the center line of the floating slider and the direction of air flow, and FIG. 7 is a diagram showing another embodiment of the floating slider according to the present invention. 8 to 11 are a plan view and a cross-sectional view of a floating slider showing another embodiment of the present invention. (1), (11) ...Floating slider, (2)
. (12)...Floating surface, (4)...Air inflow end, (7
), (14) ...groove. The same reference numerals in each figure indicate the same or corresponding parts.

Claims (2)

[Claims] (1) In a floating slider having a plurality of floating surfaces facing the recording medium and extending along the moving direction of the recording medium, the floating surface has a groove that is open at the air inflow end and closed at the air outflow end. A floating slider characterized in that it is provided along the longitudinal direction of a floating surface. (2) The floating slider according to claim 1, wherein the groove extends to a position where the closed end is close to the air outflow end of the floating slider.