JPS6282590A - Enclosed magnetic recorder - Google Patents

Abstract

PURPOSE:To obtain an enclosed magnetic recorder that can reduce heat off-track phenomena and deterioration of each part of recorder with high density and high reliability, by storing the primary component elements of the recorder such as a magnetic recording medium, a head, etc. into an enclosed container together with a refrigerant which is evaporated by the temperature on the inside of the container and then condensed by the temperature on the outside of the container. CONSTITUTION:A refrigerant 21 is evaporated by the temperature at the inside of a container 3 and then condensed by the temperature outside the container 3 in an active mode of an enclosed magnetic reproducing device. The container 3 containing the primary component elements of a magnetic disk device has an opening part 11 at the side of a base 1 and is attached to the base 1 with contact secured between an end face 13 at the side of the part 11 and a side face 1a of the base 1. The temperature on the inside of the container 3 rises up in response to the rise of the temperature of the magnetic disk device. Then the heat caused by the temperature rise is received by the liquid refrigerant 21 via an inner wall 17 of the container 3. Thus the refrigerant 21 is evaporated. In this case, the inside of the container 3 is cooled by the latent heat of evaporation and vaporization. This prevents the rise of temperature of the magnetic disk device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a technique for improving the heat dissipation characteristics of a sealed magnetic recording device in which each mechanical part is housed in a sealed container.

[Technical background of the invention and its problems] In general, in magnetic disk drives, in order to achieve large capacity and high density, the principle of gas bearings is applied to magnetic recording media (magnetic disks) with submicron order. A floating RAD slider is used to float the electromagnetic conversion head with a gap of . Since this floating RAD slider operates through an extremely small gap between the magnetic disk that rotates at high speed, even a small amount of dust entering the flying gap can cause the head to come into contact with the magnetic disk, resulting in a 1Ω scratch on the head. Therefore, in order to ensure the reliability of the device, it is necessary to keep the gas inside the device, especially around the magnetic disk head, as clean as possible.

In order to realize this, conventionally, as shown in FIG.
A structure is adopted in which the main components of the magnetic disk drive, such as the There is.

By the way, in such a sealed magnetic disk device, a plurality of stacked magnetic disks 101 are packed together with the main components in a narrow space with a high density.
It rotates at a high speed of Orpm or higher. For this reason, the sealed magnetic disk device is subjected to a considerable temperature rise of 4 degrees due to heat generation caused by viscous friction (pressure loss) between the surface of the magnetic disk 101 and the internal gas. Furthermore, heat generated from the drive unit of the head positioning mechanism 107 and the spindle drive motor (rotation support system 103) that perform high-speed random seek operations also contributes to a rise in the temperature of the apparatus.

It goes without saying that a rise in the temperature of a magnetic disk device accelerates the deterioration of each component of the device and shortens the life of the device, but the biggest problem is due to thermal expansion or uneven temperature distribution due to the rise in temperature of each component. This is the track deviation (thermal off-track) of the magnetic disk 101 due to the difference in thermal expansion, and this has been a factor that hinders improvement in track density and, by extension, in the recording density of magnetic disk devices.

However, in the above-mentioned conventional device, since the container 109 has a nearly completely sealed structure, cooling mainly involves dissipating the heat conducted through the walls of the container 109 to the cooling air passing through fins provided on the outer wall of the container 109. was at best.

In FIG. 8, the temperature drop from the inside of the device to the outside air through the wall of the container 109 is shown by a dashed-dotted line, but there is a considerable temperature difference at the interface between the wall of the container 109 and the air.
It can be seen that the thermal resistance here is large. In particular, it can be seen that this temperature difference is relatively smaller at the interface of the inner wall of the container 109 than at the interface of the outer wall.

This is because the gas inside the container 109 forms a fairly high-speed flow of several tens of m/s due to the high-speed rotation of the magnetic disk 101, so heat exchange between the inner wall surface of the container 109 and the internal gas is difficult. While it is relatively easy to do compared to the outer wall,
The air flow velocity at the outer wall of the container 109 is at most several IIl/
It is thought that this is because the heat transfer characteristics are relatively poor, being as small as S or less.

In any case, in a conventional sealed magnetic disk device, there is no doubt that the thermal resistance at the interface between the surface of the container 109 and the air is the main factor that prevents the device from improving its characteristics. In order to reduce the thermal off-track caused by the upper temperature limit of the device, which is mainly caused by wind damage with the internal gas, and to realize a high-speed access, high-density sealed magnetic disk device, a fairly large-scale installation is required. It had the disadvantage of requiring a cooling device.

[Purpose of the Invention] This invention has been made by focusing on such conventional problems, and by improving the heat dissipation characteristics, it is possible to eliminate the loss caused by the relative movement between the magnetic recording medium and the head as the main cause. The purpose of the present invention is to provide a sealed magnetic disk device that can suppress the temperature rise inside the device and realize high recording density and high-speed access with little thermal off-track.

[Summary of the Invention] In order to achieve this object, the present invention stores main components of a magnetic recording device such as a magnetic recording medium and a head in a sealed container, and provides a space inside the wall of the container. The space is filled with a refrigerant that evaporates at the temperature inside the container and condenses at the temperature outside the container when the magnetic recording device is in operation.

[Action of the invention] The temperature inside the container rises by 8 degrees due to the operation of the magnetic recording device.

The refrigerant sealed in the inner space of the wall of the container receives heat due to this temperature rise through the inner wall of the container and evaporates, and the latent heat of evaporation at this time cools the inside of the container. The evaporated refrigerant is cooled by the outside air through the outer wall of the container, releases heat, and condenses. By repeating such a cycle of evaporation and condensation of the refrigerant, heat is radiated within the container, and an upper limit of the temperature within the apparatus is prevented.

[Example] The present invention will be explained in detail below.

FIG. 1 and FIG. 2 show a first embodiment of the present invention, and the structure thereof will be explained first.

A container 3, which is shown in a perspective view in FIG. 2, is attached to the base 1 shown in FIG. 1 with the container interior 5 sealed.

Inside the container 5, a plurality of laminated magnetic disks (la
The magnetic disk 7 is rotatably supported by a spindle 9, and the spindle 9 is further connected to the base 1.
It is driven by a drive motor (not shown) inside. This drive motor, spindle 9, etc. constitute a drive mechanism.

Although not shown inside the container 5, a head and a head support system for recording and reproducing information on a magnetic disk 7, which is substantially similar to that shown in FIG. A head positioning mechanism for positioning the head is housed.

The container 3 that seals and stores the main components of the magnetic disk drive has an opening 11 on the base 1 side, and is attached to the base 1 with the end surface 13 on the side of the opening 11 in contact with the side surface 1a of the base 1. It is. The upper part of the container 3, the side opposite to the opening 11, and the walls of the portion of the container 3 having a semicircular cross section on both end sides in the arm direction are in communication with each other, and the outer wall 15, the inner wall 17, and the end surface are connected to each other. A sealed space 19 surrounded by 13 is provided. Based on the principle of a heat pipe, a refrigerant that is spontaneously generated at the temperature inside the container 5 when the magnetic disk device is in operation and condenses at the temperature outside the container is sealed in the space 19 until it reaches the upper surface of the container. There is. As shown in FIG. 1, the refrigerant 21 is in a liquid state and is in contact with the entire side wall 23 of the container interior 5 in the space 19, and is sealed with a small space above.

Further, a plurality of radiation fins 25 are attached to the upper surface of the container 3. The radiation fins 25 are for improving the cooling effect of the refrigerant 21 that has evaporated by receiving the heat inside the container 5.

In a sealed magnetic disk device with such a heat dissipation mechanism, when the device is operated, the magnetic disk 7 is rotated at high speed, resulting in viscous friction (windage loss) between the surface of the magnetic disk 7 and the gas (air). The temperature of the magnetic disk device increases due to heat generation and further heat generation from the drive unit of the head positioning mechanism (not shown) that performs high-speed random seek operations and the drive motor of the spindle 9.

As the temperature of the magnetic disk device increases, the temperature inside the container 5 rises, and the liquid refrigerant 21 receives heat due to this temperature upper limit via the inner wall 17 of the container 3, and the refrigerant 21 evaporates.

The interior of the container 5 is cooled by the latent heat of evaporation at this time,
Temperature rise in the magnetic disk device is suppressed. The evaporated refrigerant gathers at the upper side of the space 19, is cooled by the outside air through the radiation fins 25 and the outer wall 15 of the container 3, radiates heat, condenses, becomes liquid again, and drips to the lower side of the space 19. By repeating such a cycle of evaporation and condensation of the refrigerant, heat dissipation within the magnetic disk device is performed efficiently.

FIG. 3 shows a second embodiment. In this embodiment, a fine mesh member 27 is installed on the left side and top surface of the side wall surface 23 of the container interior 5 in the space 19, and radiation fins 25 are extended from the top surface of the container 3 to the bottom of the side surface. Therefore, the old refrigerant 21 was used in less container 3 than in the above-mentioned embodiment.
It barely reaches the bottom edge of the side wall.

With this configuration, the refrigerant 21 spreads between the mesh member 27 and the side wall surface 23 of the container interior 5, which has one space, due to capillary action, so that ω of the refrigerant 21 can be reduced, and the same effect as in the previous embodiment can be achieved. Since the refrigerant 21 comes into contact with the entire inner wall 17 of the container 3, the heat absorption effect can also be maintained at the same level. In addition, since the heat dissipation section to which the heat dissipation fins 25 are attached is provided not only on the top surface of the container 3 but also on the side surface thereof, the heat dissipation characteristics are significantly improved compared to the above-mentioned embodiments. Other configurations and operations are similar to those of the previous embodiment.

FIGS. 4 and 5 show a third embodiment. In this embodiment, the container 3 is first formed as a plate material having a plurality of independent spaces 19 in the longitudinal direction of the container 3 by extruding metal, etc., and then bent and welded together at the ends of the plate material. Furthermore, a side plate 29 is attached in a sealed state to the side opposite to the opening 11 on the base 1 side, and a refrigerant 21 is sealed in one space. Other configurations and functions are shown in Figure 1.

This is similar to the first embodiment shown in FIG. In addition, the fourth
In the figure, the magnetic disk and the like inside the container 5 are omitted.

FIG. 6 is a sectional view of the vicinity of the upper surface of the container 3 showing the fourth embodiment. In this embodiment, a large number of grooves 31 are formed in an annular shape over the entire outer wall 15 of the container 3 to form a space inside the wall of the container 3, and a sealing member 33 covering the grooves 31 is joined to the outer wall 15 over the entire circumference. A refrigerant 21 is sealed between the sealing member 33 and the outer wall 15. In this embodiment, the radiation fins 25 are arranged in a direction perpendicular to the arrangement direction of each of the above-described embodiments. In such a configuration, the thermal resistance at the inner wall 17 of the container 3 is the same as before, but the conventional container can be used as is by providing the groove 31, and the heat resistance at the outer wall 15 of the container 3 can be reduced with an extremely simple configuration. Resistance can be reduced.

In the second to fourth embodiments described above, the same components as those in the first embodiment are given the same reference numerals and explained.

[Effect of the invention 1 As described above, according to the present invention, a refrigerant is sealed in the space provided inside the container wall of a closed magnetic recording device, and the inside of the container is cooled by the evaporation and condensation of this refrigerant. There is no need to install a separate large-scale cooling mechanism (compared to the conventional method in which heat dissipation fins are simply attached to the outer wall of the container), the heat dissipation characteristics are significantly improved, and there is less heat off-track and deterioration of various parts of the equipment. A high-density, highly reliable sealed magnetic recording device can be realized.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a sealed magnetic disk device according to a first embodiment of the present invention, FIG. 2 is a perspective view of a container in the device of FIG. 1, and FIG. FIG. 4 is a sectional view similar to FIG. 1, FIG. 4 is a sectional view similar to FIG. 1 of the third embodiment of the present invention, FIG. 5 is a perspective view of the container in the apparatus of FIG. 7 is a sectional view of a conventional sealed magnetic disk drive; FIG. 8 is a sectional view of the inside and outside of the container wall of the device shown in FIG. 7; FIG. 3... Container 7... Magnetic disk (magnetic recording medium) 19... Space 21... Refrigerant Figure 3

Claims (1)

[Claims] A magnetic recording medium, a head for recording and reproducing information on the magnetic recording medium, a drive mechanism for generating relative movement between the magnetic recording medium and the head, and a drive mechanism for positioning the head at a predetermined position on the magnetic recording medium. In a closed magnetic recording device having a head positioning mechanism for positioning and storing the head positioning mechanism in a sealed container, a space is provided inside the wall of the sealed container, and the operation of the closed magnetic recording device is 1. A closed magnetic recording device characterized in that a refrigerant that evaporates at a temperature inside the container and condenses at a temperature outside the container is sealed in the space.