KR100422977B1 - Small hard disk drive device preventing disk slip by controlling range of lubricant layer or using material having large coefficient of friction - Google Patents

Abstract

PURPOSE: A small hard disk drive device preventing disk slip by controlling a range of a lubricant layer or using a material having large coefficient of friction is provided to improve the reliability and the yield. CONSTITUTION: A Ni-P layer is formed on a substrate to improve a mechanical characteristic of a magnetic disk. A Co and Cr layer is formed on the Ni-P layer to show a magnetic characteristic of the magnetic disk. A carbon layer is formed on the Co and Cr layer to protect the Co and Cr layer and the Ni-P layer. A lubricant layer is formed on the carbon layer to protect the magnetic disk when a head and the magnetic disk contact with each other, wherein the lubricant layer is not formed at an area(1) contacting with a bottom of a clamp receiving clamping force.

Description

Small hard disk drive unit that prevents disk slip.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small hard disk drive device that prevents disk slipping. In particular, the present invention relates to an external impact or thermal stress during the manufacturing process or after the completion of manufacturing in a small hard disk drive of 2.5¨ or less. The present invention relates to a disk cross-sectional structure capable of preventing such a disk slip phenomenon by causing slippage of the magnetic disk from its original position due to the like.

In general, as a secondary storage device, a hard disk drive is an important element of a computer. Moreover, in today's multimedia environment, high capacity is inevitable through high-density recording of hard disk drives, and accordingly, the drive industry is trying to preempt any high ground for coping with high capacity through the development of new heads and media as well as more innovative technology. The competition is fierce.

In addition, hard disk drive is a mechatronics product composed of electronic devices and mechanical devices. The hard disk drive is a secondary memory device that records and reproduces information by sending a digital signal to a head that acts as an electromagnet and recording the information on a disk having magnetic properties. One.

In general, a hard disk drive has a base, which is the foundation of all components, a magnetic head for input / output, an actuator for moving the magnetic head to a desired position, and information from a magnetic material. It consists of a number of disks stored, a spindle motor that rotates the disk at a constant circumferential speed, and a cover and gasket that seals off these components from the outside. have. The configuration of the hard disk drive as described above will be easily understood by those skilled in the art.

Referring to the operation state of the compact hard disk drive configured as described above, when the power of the drive is "on", the spindle motor is rotated at a constant circumferential speed, accordingly, the disk fixed to the spindle motor is also rotated at a constant speed. Subsequently, when the disk rotates at a high speed, the magnetic head floats to a constant height by the pressure of the air film generated on the surface of the disk. In this state, the head moves to a track position on the disk, and the drive sends a signal to the host computer that it is ready to execute a command through the interface.

When read / write information is input while the drive is ready for operation, the actuator rotates about the pivot axis according to the position signal and the speed signal of the control circuit, and the read / write head fixed to the end of the actuator is placed on the disk. You will move to the desired position (schedule track). Thereafter, the read / write circuit portion subsequently causes the head to perform a read / write operation. At this time, the position and speed of the magnetic head are controlled by the control circuit unit even during the read / write operation.

In the above hard disk drive, as shown in FIG. 1, a spindle motor 60 connected to a printed circuit board installed below the base plate 10 by a flexible printed circuit is positioned at the center of the base. In the hub of the spindle motor 60 fixed with fasteners or adhesives, a plurality of disks 20 are installed. A clamp 50 is installed at the top of the disks 20, and the disk 20 is fixed by fastening to the upper surface of the spindle motor 60 using one screw 40. The spacer 30 is installed between the plurality of disks 20 to maintain the gap and to fix the spacers due to friction with the contact surface.

In the disk fastening device that is required to fasten a plurality of disks in accordance with this high capacity trend, as shown in Figure 2, the disk located on the lower side in the process of assembling the plurality of disks 20 to the spindle motor 60 is the clamp According to the weight of the disk 50 and the spacer 30 and the disk located at the top, it is firmly fixed to the spindle motor 60 compared to the disk located at the top. In other words, the mass or inertia is increased, so that it is firmly fixed than the top disc.

At this time, the disc located at the top is fastened with the screw 40 by the clamp 50, the vertical force (clamping force) to fasten with the screw 40 is limited. Do not tighten too loosely, too much may damage the disc. In this relationship, the frictional force generated on the disk surface according to the vertical force is as follows.

F = μ · N where F denotes the frictional force generated on the disc, μ denotes the friction coefficient between the clamp and the disc, and N denotes the clamping force generated by screwing. As already described in the above formula, as the vertical force increases, the friction force increases, and when the vertical force decreases, the friction force also decreases. Therefore, in order to increase the friction force due to the limitation of the vertical force, the friction coefficient must be increased.

As shown in Figure 3, looking at the cross-sectional structure of a conventional conventional disk, it is applied in multiple layers. At the bottom, aluminum (Al) or glass (glass) is used as a support layer on which the magnetic disk 20 is based. On the support layer, a nickel (Ni) -phosphorus (P) layer (underlayer) is applied to improve the mechanical properties of the magnetic disk. Cobalt (Co) and chromium (Cr) layers are coated on the nickel-phosphorus layer as a layer showing magnetic properties of the disk. The cobalt and chromium layers are layers for performance. Subsequently, a carbon layer (overlayer-overlayer) is coated on the cobalt and chromium layers. This serves to protect the layers located below the carbon layer. Above the carbon layer is a layer located on the top of the disk, the lubrication layer to protect the disk during contact or landing between the head and the disk.

However, in the general disc cross-sectional structure as described above, the vertical force generated when the disc is clamped to the spindle cap with the clamp, as described above, has a limitation in the characteristics of the disc. It often happens on hard disk drives. This is because such a small hard disk drive can only use one screw to secure the clamp. Therefore, there is a limit to increasing the clamping force as desired.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to adjust a range of a lubrication layer or to prevent disk slip by using another material having a large coefficient of friction, thereby providing a high reliability small hard disk drive To provide a device.

Another object of the present invention is to provide a small hard disk drive device capable of increasing the process yield by preventing disk slip.

In order to achieve the above object, the most preferred embodiment according to the spirit of the present invention is to prevent the disk slip phenomenon by increasing the friction force in the area where the bottom surface of the clamp receiving the clamping force is in contact with the fixed disk It is characterized by not applying a lubricating layer to the area.

1 is an exploded perspective view illustrating a state in which a disk is fastened by using a fastening device in a small hard disk drive according to a conventional embodiment.

Figure 2 is a partial cross-sectional view showing a state in which the disk is fixed to the spindle motor using a fastening device according to a conventional embodiment

Figure 3 is a cross-sectional view showing the structure of the disk surface in contact with the clamp of the fastening device according to a conventional embodiment

Figure 4 is a plan view showing a disk surface in contact with the clamp of the fastening device according to an embodiment of the present invention

Figure 5 is a cross-sectional view showing the structure of the disk surface in contact with the clamp of the disk fastening device in a small hard disk drive according to an embodiment of the present invention

Figure 6 is a cross-sectional view showing the structure of the disk surface in contact with the clamp of the disk fastening device in the hard disk drive according to another embodiment of the present invention

Explanation of symbols on the main parts of the drawing

1; contact surface between clamp bottom and disk

20: disk 30: spacer

40: screw 50: clamp

100: hard disk drive

Hereinafter, with reference to the accompanying drawings will be described in detail the most preferred embodiment of the present invention. First, in describing each of the drawings, the same components have the same reference numerals as much as possible even though they are shown in different drawings. In describing the present invention, when it is determined that description of related known functions or configurations may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

As shown in Figures 4 and 5, looking at the cross-sectional structure of the disk according to an embodiment of the present invention, as in the prior art is applied in multiple layers. At the bottom, aluminum (A) or glass is used as a support layer on which the magnetic disk is based. On the support layer is applied a nickel-phosphorus (Ni-P) layer (called an underlayer) to improve the mechanical properties of the magnetic disk. Cobalt (Co) and chromium layer (Cr) are coated on the nickel-phosphorus layer as a layer showing magnetic properties of the disk. The cobalt and chromium layers are layers for performance. Subsequently, a carbon layer (called an overlayer) is coated on the cobalt and chromium layers. This serves to protect the layers located below the carbon layer. Above the carbon layer is a layer located on the top of the disk, the lubrication layer to protect the disk during contact or landing between the head and the disk. At this time, by adjusting the range of the region of the lubricating layer located on the top of the disk, the present invention can be applied.

FIG. 6 is a small hard disk drive device preventing disk slip according to another embodiment of the present invention. Referring to the drawings, the disk cross-sectional structure is composed of a plurality of layers as in the prior art. That is, at the bottom, aluminum (A) or glass is used as a support layer on which the magnetic disk is based. On the support layer is applied a nickel-phosphorus (Ni-P) layer (called an underlayer) to improve the mechanical properties of the magnetic disk. Cobalt (Co) and chromium layer (Cr) are coated on the nickel-phosphorus layer as a layer showing magnetic properties of the disk. The cobalt and chromium layers are layers for performance. Subsequently, a carbon layer (called an overlayer) is coated on the cobalt and chromium layers. This serves to protect the layers located below the carbon layer. Above the carbon layer is a layer located on the top of the disk, the lubrication layer to protect the disk during contact or landing between the head and the disk. At this time, by adjusting the range of the region of the lubricating layer located on the top of the disk, the present invention can be applied. That is, when the disk is fastened to the spindle motor by the fastening device, the clamp bottom surface of the fastening device comes into contact with the lubrication layer of the disk. By removing the contact surface of the lubrication layer, the bottom surface of the clamp is the carbon of the disk. It is in contact with the layer. At this time, the friction coefficient between the carbon layer and the bottom surface of the clamp is larger than the lubrication layer, and as a result, the removal of the lubrication layer on the contact surface increases the frictional force.

As described above, the present invention is effective in preventing disk slip in a small hard disk drive apparatus by increasing friction between the bottom surface of the clamp and the contact surface of the disk. On the other hand, in the detailed description of the present invention has been described with respect to specific embodiments, it is obvious to those skilled in the art that various modifications are possible without departing from the scope of the present invention.

Claims (1)

In the hard disk drive device, It is characterized in that the lubricating layer is not applied to the area in order to prevent the disc slipping by increasing the frictional force in the area 1 holding the clamp 20 in contact with the bottom surface of the clamp 50 subjected to the clamping force. Small hard disk drive unit that prevents disk slip.