JPH0359859A - floating head slider - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a floating head used in a magnetic disk drive, and more particularly to a head slider rail shape suitable for obtaining a stable head flying height.

[Conventional technology]

The slider rail of the conventional floating head was published in Japanese Patent Application Laid-open No. 49-1.
As shown in Japanese Patent No. 21514, a type having a tapered part and a flat part and having a linear shape in the longitudinal direction of the slider rail is often used.

Other known examples include Japanese Patent Laid-Open No. 62-231481, which aims to obtain desired dynamic performance and stability by increasing the pitch angle of flight.
A floating type RAD slider is one in which the slider rail width at the air outflow end is narrower than the slider rail width at the air inflow end.

[Problem to be solved by the invention]

As the recording density of magnetic disk devices increases, the flying height of the head tends to decrease, and stabilization of the flying height of the head has become an important technical issue in order to avoid collisions between the disk and the head.

The causes of variations in head flying height can be broadly divided into two types: flying height variations due to manufacturing variations and dynamic flying height variations during device operation. Among these, measures have been taken to reduce dynamic flying height fluctuations during device operation, such as reducing the fluctuating external force applied to the head slider, but it has become difficult to reduce the external force due to increased access speeds, etc. It's coming.

The head slider floats due to an air film generated on the slider rail. Another method for reducing dynamic flying height fluctuations and stabilizing the head flying height is to increase the stiffness and damping of this air film. However, in a conventional floating head that has a tapered part and a flat part and is linear in the longitudinal direction of the slider rail, the stiffness and attenuation of the air film are determined by the head flying height and head pressing by the load. Head pressing increases the rigidity of the air film by increasing the load, but the damping ratio decreases, which is not necessarily advantageous, and also increases damage when the head contacts the disk. Head C5/S (contact start ・
There are problems such as an increase in the contact force between the head and the disk when the disk is stopped.

An object of the present invention is to stabilize the head flying height by increasing the rigidity and damping of the air film by changing the shape of the head slider rail without changing the head flying height or head pressing load.

[Means to solve the problem]

In order to achieve the above purpose, in the head slider,
The slider rail width at the air outflow end was made larger than the slider rail width at the air inflow end, and the depth of the groove portion other than the slider rail portion was set to 10 μm or more and 25 μm or less.

[Effect]

As described above, in the head slider, the slider rail width at the air outflow end was made larger than the slider rail width at the air inflow end, and the depth of the groove portion other than the slider rail portion was set to be 10 μm or more and 25 μm or less. As a result, the portion where the rail width increases at the air outflow end functions as a step bearing, and positive pressure of the air film is generated there, thereby increasing the rigidity. On the other hand, since the rail width increases toward the air outflow end, damping increases due to the squeeze effect.

In this way, the rigidity and damping of the air film can be increased, and the flying height of the head can be stabilized.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. The head of this embodiment has a tapered portion 1 and a flat portion 2, similar to conventionally applied heads. The magnetic circuit unit 5 for reading and writing information is provided at the outflow end of the airflow as in the conventional case.In the case of a zero head, the width of the slider rail at the outflow end of the airflow is equal to the flat part 2 at the inflow end of the airflow. 35 compared to
It has expanded by about %. Further, the depth of the groove portion 4 that does not generate air pressure is 20 μm as shown in FIG.

With such a structure, the flat portion 3 has a function as a step bearing, and the rigidity of the air film can be increased. Furthermore, since the flat portion 3 has a wider slider rail width than the flat portion 2, a squeezing effect occurs in this portion, increasing attenuation.

The results of numerically calculating the stiffness and damping coefficient of the air film of this example under certain conditions are shown in FIGS. 5 and 6. Figure 4 shows the motion modes considered in the calculation. Under the same conditions, we numerically calculated the stiffness and damping coefficient of the air film of a conventional floating head that has a tapered part and a flat part as shown in Figure 3 and has a linear shape in the longitudinal direction of the slider rail. Figure 5,
It is shown in conjunction with Figure 6. This numerical calculation shows that during vibration at 20 kHz, the stiffness in the vertical direction is improved by about 8%, and the stiffness in the pitching direction is improved by about 15%.

Further, the damping coefficient in the vertical direction is about 2.7 times, and the damping coefficient in the pitching direction is about 3.6 times, which shows a large effect.

In this way, according to this embodiment, the head flying height and head pressing can be stabilized by changing the head slider rail shape by increasing the rigidity and damping of the air film without changing the load. It has the effect of

〔Effect of the invention〕

According to the present invention, the rigidity and damping of the air film can be increased by changing the head slider rail shape without changing the head flying height or head pressing load.
This has the effect of stabilizing the head flying height.

[Brief explanation of drawings]

FIG. 1 is a front view of the r embodiment of the present invention, FIG. 2 is a side view of the present embodiment, FIG. 3 is an explanatory diagram of a conventional floating head, and FIG.
The figure is an explanatory diagram showing the motion mode of the Herad slider, Fig. 5 is an explanatory diagram showing the numerical calculation results of air film stiffness of the embodiment and the conventional head, and Fig. 6 is the numerical value of the air film damping coefficient of the embodiment and the conventional head. It is an explanatory diagram of a calculation result. 1... Part of the taper. 2...Flat part on the inflow end side. 3...Flat part on the outflow end side. 4...Groove. 5...Magnetic circuit section. Muscle rigidity 0 20th Horse Cheer

Claims (1)

[Claims] 1. A floating head slider used in a magnetic disk drive, characterized in that the slider rail width at the air outflow end is larger than the slider rail width at the air inflow end.