JPH0258781A - Disk device - Google Patents

Abstract

PURPOSE:To secure required pressing force without distorting disks by providing an interval member provided with an elastic member on at least one side surface and holding the disks with the pressing force by compressing the interval member with a compressing member provided to a rotating member after the disks are put on the rotating member. CONSTITUTION:A magnetic disk 7a one surface of which is brought into contact with the supporting surface 25a of a flange section 25b, spacer 8a, disk 7b, interval member 30 made of an elastic material, disk 7c, space 8c, and disk 7d are successively put on a hub 25 and the disks, spacers, and interval member are fixed by means of a compressing member 29 fixed to the top of the hub 25 by means of a screw 26 screwed into a tapped hole 25d in a state where the interval member 30 is compressed in the axial direction. As a result, the interval member 30 appropriately make elastic deformation and application of local or excessive force to the disks 7a-7d can be prevented. Moreover, the interval member 30 absorbs the finishing error of the disks 7a-7d and rotating member 25 and differences in thermal expansion and contraction between the disks and rotating member when the materials used for the base plates of the disks and rotating member are different from each other. Therefore, required pressing force can be secured without distorting the disks.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a disk device equipped with a disk-shaped data recording medium such as a magnetic disk or an optical disk.

[Conventional technology]

3 to 5 show an example of a conventional magnetic disk device. FIG. 3 is a side sectional view of the magnetic disk device, FIG. 4 is a plan view of the disk cap, and FIG. 5 is a plan view of the disk mounting section. It is a partial sectional view showing details. In these figures,
The container (1) is composed of a base (2) and a cover (3) fixed to the base (2) in a substantially airtight manner. (
4) is a spindle motor which is an example of a rotational drive device fixed to the base (2), and (5) is a spindle motor (4).
) is a rotating member, in this example, a hub, which is fitted onto the shaft (4a) and rotationally driven by the spindle motor (4). The hub (5) has a flange portion (5b) on the spindle motor (4) side.
) has a supporting surface (5a) and its top (5C)
6 large screws (5d) for screws (6) (Fig. 5)
and a guide (5e), and the disks (7a) to (7d) for magnetically recording data have one surface of the disk (7a) in contact with the support surface (5a) of the hub as shown in the figure. annular spacers (8a) to (8C) which are spacing members that keep the disks (7a) to (7d) at regular intervals;
, disks (7b) to (7d) are installed alternately. (9) is a disk cap, the plan view of which is shown in Figure 4, which has a central hole (9a) in the center and a thin walled portion (9b) around it so that it can be elastically deformed. ,
This thin part (9b) has six holes (9u) for screws (6).
) to (9z), and the outermost periphery has a thick presser part (
9C). The discs (7a) to (7d) attached to the hub (5) fit through the holes (
9u) to (9z) through which six screws (6) (only one is shown in Fig. 5; illustration is omitted in Fig. 3) are inserted into the hub (5). screw hole (5d)
(Fig. 5) to fix the disc cap (9).
9C) presses and holds the disks (7a) to (7d). In addition, when the guide (5e) provided on the hub engages with the center hole (9a) of the disc cap (9) and fixes the disc cap (9) to the hub (5), the center of the disc cap (9) It functions to determine the position of the 00 is a head for reading and writing data recorded on the disk, αυ is a suspension fixed to the arm @ and supporting the head αO, and this suspension Qη
During the rotation of the disks (7a) to (7d), the air film on the surface of the disks (7a) to (7d) causes the head 00 to bend by about 0.3 [μm].
d) away from the surface.

Next, with reference to FIG. 5, the operation of clamping and fixing the disks (7a) to (7d) using the disk cap (9) will be explained. First, disks (7a) to (7d) and spacers (8a) to (8C) are alternately mounted on the hub (5) as shown. Next, the disc cap (9) is attached to the top of the hub (5C) by engaging its center hole (9a) with the guide (5e) provided on the hub, and the disc cap (9) is attached to the top of the hub (5C).
Align the centers of the holes (9u) to (9z) in 9) with the screw holes (5d) provided in the hub (5) (only one hole is shown in Figure 5), then tighten the screws (6). Hole (9u) ~ (9z)
The disc cap (9) is fixed to the hub (5) by passing through the screw hole (5) and screwing it into the hub (5), but before tightening the screw (6), the thin part (9b) of the disc cap (9) and Hub (5) so that there is a slight gap α■ between it and the top of the hub (5C).

Discs (7a) to (7d), spacers (8a) to
(8C).

The dimensional relationship of the disc cap (9) is designed,
That is, the disc cap (9) is in the shape shown by the dashed line in FIG. From this state, insert the screw (6) passing through (9z) into the hole (9u) of the disc cap (9), for example, through the hole (9u) p (9v) - (9
W) - followed by hole (9x), (9Y) p (9z)
Tighten the screws about half way in this order, and then tighten the holes (9u) again.
(9v), (9W) screws, holes (9x), (9y)
.

Tighten the screws (9z) in this order until the thin walled portion (9b) of the disc cap (9) is elastically deformed and comes into contact with the top (5C) of the hub (5) (as shown by the solid line in Figure 5). hub cap condition). In this way, hole (9u) ~
By sequentially and evenly tightening the screws corresponding to (9z) several times, it is possible to prevent the disks (7a) to (7d) from being fixed in a distorted state due to uneven force being applied to them.

Furthermore, although the components installed and fixed as described above expand and contract due to thermal expansion and contraction due to changes in ambient temperature, the axial tightening force of the disks (7a) to (7d) is not changed due to this expansion and contraction. Discs (7a) to (7d)
) and the spacers (8a) to (8C) must match the amount of axial expansion and contraction of the hub (5). Substrates (7a) to (7d), spacers (8a) to (
sc) The p-hubs (5) are all constructed of the same material, for example aluminum.

However, in recent years, glass with good flatness has been used to improve the performance of disks, which are magnetic data recording media.
In this case, the material of the disks (7a) to (7d) has been changed to glass, so that the disk (7a) is used as a substrate for a) to (7d) due to temperature changes.
Amount of expansion and contraction of ~(7d) and spacers (8a) ~(8C) (
Since the amount of expansion and contraction of the cap (aluminum) does not match the amount of expansion and contraction of the cap (5) (aluminum), the tightening force with the disc cap (9) changes greatly depending on temperature changes.

Since the operation of the magnetic disk device configured as described above is well known, the details will be omitted.
) to (7d) are rotated at high speed (e.g., 3,600 revolutions/min) by the spindle motor (4), and the head αQ is moved approximately 0.3 Ctt m) from the surface of the disks (7a) to (7d). An actuator (not shown) quickly moves the head QO held by the arm (6) via a suspension (1υ) to a predetermined position on the surface of the disks (7a) to (7d) to read and write data. .

In order to record a large amount of data in a magnetic disk device, the data recording density of disks (7a) to (7d) is extremely high, and disks (7a) to (7d) are attached to the hub (5). It is important to prevent distortion when pressing and fixing with the disk cap (9), and it is also necessary to press with a stable force against expansion and contraction due to temperature changes.

[Problem to be solved by the invention]

The disks (7a) to (7d) have a thickness of, for example, 1.9 (
A magnetic material of 1 to 0.1 mm is coated on an aluminum substrate (disc) by coating, sputtering, plating, etc.
It is formed on a magnetic film with a thin layer of about 1 μm], and when it is pressed strongly, distortion occurs, and the disks (7a) to (7d
) may cause errors in reading and writing data. Therefore, the disks (7a) to (7d) are mounted on the hub (5),
In order to prevent large distortions or local distortions from occurring due to uneven pressing force on the discs (7a) to (7d) when fixed with the disc cap (9), the method described in the conventional example above is used. Hub (5) with disc cap (9) like
) to tighten the screws in the disc cap holes (9u), (9v), (9W), hole (9X) p
(cry) t Although the screws (9Z) were tightened by about half in the order and the screws were tightened again in the same order, there was still a risk that uneven force would be applied to the disks (7a) to (7d). In addition, in order to make the pressing force on the discs (7a) to (7d) a predetermined value in the initial assembled state, the top part of the hub (5C) and the thin part (9b) of the disc cap should be tightened beforehand. The dimensions of the gap (g) must be managed so that it falls within a predetermined range. This is because the thin part (9b) of the disc cap is elastically deformed by the gap α1, so that the discs (7a) to (7)
This is because a pressing force is applied to d). Therefore, in order to manage the dimensions of this gap α frame, hub (5), disks (7a) to (7d), e-spacers (8a) to (8C
) #The processing accuracy of the disk cap (9) had to be extremely high.

Furthermore, when glass is used as the substrate for the disks (7a) to (7d), the pressing force on the disks (7a) to (7d) does not change significantly even with thermal expansion and contraction caused by changes in ambient temperature. A solution was needed to do this.

This invention was made in order to solve the above-mentioned problems, and it is possible to easily assemble the disc without causing distortion, and also to solve the problem when the material of the disc is different from the material of the hub, which is a rotating member. However, it is an object of the present invention to provide a disk device in which the pressing force on the disk does not change significantly due to thermal expansion and expansion/contraction, and the required pressing force is ensured.

[Means to solve the problem]

In the disk device according to the present invention, a spacing member made of an elastic material is provided on at least one surface of the disk, and the one surface of the disk is in contact with the rotating member directly or via the spacing member. The rotating member is provided with a compression member that is attached to the rotating member and compresses the spacing member by contacting the other surface of the disk directly or via the spacing member.

[Effect]

In this invention, by appropriately elastically deforming the spacing member made of an elastic material, it is possible to prevent local or excessive force from being applied to the disk and cause distortion, and also to prevent processing errors in the disk or rotating members. When the material of the substrate of the disk is different from the material of the rotating member or the material of the spacing member, the difference in thermal expansion and contraction between the two is absorbed, and the pressing force necessary for fixing the disk is always applied.

[Embodiments of the invention]

FIG. 1 is a partial cross-sectional view of a disk mounting portion showing an embodiment of the present invention. In the figure, (4) to (8C) are the same as those of the conventional device, and therefore their explanations will be omitted.

(C) is a hub, which is almost the same as the conventional example above, but
The length from the support surface (25a) of the lower flange portion (25b) to the top (25C) is slightly shorter than that of the conventional example, that is, the length of the disc (7a) of the conventional example (FIG. 5).
- (It is manufactured so that it is approximately equal to the dimension of 7 plus the axial dimension of spacers (8a) to (8C),
There is a screw hole (25d) and a guide (25e) on the top (25C).
)have. (to) is a spacing member made of a tidy material, synthetic rubber in this example, which is provided on one surface of the magnetic disk (7b). The magnetic disk (7a) with one side in contact with the surface (25a), the spacer (8a) #disk (7b), and the spacing member (1), the disk (7c),
Spacer (8C) t disk (7d) is installed, and spacer member ■ is compressed in the axial direction by the compression member fixed to the screw hole (25d) at the top of the hub with six screws. Fixed. The compression member has a disc-like shape with sufficient rigidity, and has a central hole (
29a) and a through hole (2gb) for the screw (c) around it.
It has six disk caps (9) and has a planar shape similar to that of the disk cap (9) shown in FIG. Spacing member (to)
Before it is compressed by the compression member, the disk (
The upper surface of 7d), that is, the surface on the compression member side, protrudes above the top of the hub (25C), and in this state, the center hole (29a) of the compression member and the guide (25e) of the hub are engaged. After that, the screw (1) is passed through the through hole (29b) of the compression member and tightened to the hub), and the synthetic rubber spacing member (g) is compressed to assemble the disks (7a) to (7d).

In this case, the mutual dimensions of the disks (7a) to (7d) are the support surface (25a) of the flange part of the hub and the top (25a).
C) and the axial dimensions of the spacers (8a) and (8C), and are determined to be a predetermined dimension, and are not affected by the compression margin or the elastic modulus of the spacing member (1).

FIG. 2 shows still another embodiment, in which each spacing member (
40a) to (40C) are made of three cosynthetic rubber spacing members, and the length of the elastic spacing member in the axial direction is three times that of the above-mentioned embodiment (there are three spacing members). Therefore, the hub (c), disks (7a) to (7d
) has three times the ability to absorb dimensional errors, and the disc (7
The change in pressing force from a) to (7d) can be reduced to 1/3.

In addition, in the above embodiment and other embodiments, for example, the hub (c), the substrates of the disks (7a) to (7d), and the spacers (8a) and (8b) are made of metal materials such as aluminum and brass, glass or The spacing members (1)t (40a) to (40a) are made of synthetic resin or the like having sufficient rigidity.
Regarding 0C), it is possible to use an appropriate combination of synthetic resins having appropriate elasticity in addition to synthetic rubber, and the same applies when there is only one disk.

Further, although the case where the disk is a magnetic disk has been described, the same effect can be obtained even if the disk is of another data recording method such as an optical disk.

Although an example is shown in which the compression member is fixed to the rotating member with six screws, the number of screws may be increased or decreased as necessary. For example, the number of screws may be increased or decreased as required. A compression member using a screw and a nut that is screwed into the screw.
You may also use methods such as tightening the

Further, for example, in the above other embodiments, the spacing member (40
Since it is possible to arbitrarily select the tensile coefficient of a) to (40c) using glass fiber-containing nylon resin, the hub (c) and discs (7a) to (7d) can be made of nylon resin depending on the material type. ) for the amount of thermal expansion and contraction of disk (7a)
~ (7d) The sum of the thermal expansion and contraction amounts of the spacing members (40a) ~ (40C) can be made to approximately the same value, and the disc (7a) ~ due to the thermal expansion and contraction of these materials.
(It is also possible to greatly suppress the change in the pressing force to
When a) to (40C) are provided, the thermal expansion coefficient of the spacing member is a value obtained from the following formula, where n: number of disks (four in the other embodiments) tl:
Thickness of disk [related] t2: Thickness of spacing member [related] (spacing member (40a) ~ (
.
:] This objective can be achieved by selecting the value (K) calculated by the calculation formula: K2: Thermal expansion coefficient of the hub.

For example, in the above other embodiments, t, = 1.9 (
II) jtt = 5.1 [im) t n = 4
C], and if the substrates of disks (7a) to (7d) are made of glass, then is approximately 8 x 10'6. If the material of the hub (a) is aluminum, then is approximately 10 pieces, so K : 30.45 The thermal expansion coefficient in (2) may be calculated and the spacing member may be adjusted to approximately match this value.

Incidentally, even if the thermal expansion coefficients of the spacing members (4oa) to (40c) etc. are not adjusted, if there is an elastic material having a value close to the value calculated by the above equation (1), it may be used as is.

〔Effect of the invention〕

As described above, according to the present invention, a spacing member made of an elastic material is provided on at least one surface, a disk is attached to a rotating member, and the spacing member is compressed by a compression member provided on the rotating member. As a result, the disk is configured to be pressed and clamped in the axial direction, so the necessary pressing force on the disk can be secured regardless of the accuracy of the rotating parts and the machining dimensions of the disk, and it also prevents excessive force from being applied to the disk during assembly. This has the effect of preventing distortion from occurring on the disk and eliminating data read/write errors caused by this distortion. Furthermore, even if the rotating member and the disk are made of different materials, the difference in thermal expansion and contraction between the two is absorbed by the spacing member, so thermal expansion and contraction will not cause excessive force to be applied to the disk and cause distortion. Alternatively, it is possible to obtain a disk device in which there is no risk of insufficient pressing force on the disk.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view of a disk mounting section showing one embodiment of the present invention, FIG. 2 is a partial sectional view showing another embodiment of the invention, and FIGS. 3 to 5 are conventional magnetic disk devices. An example is shown in FIG. 3, which is a side sectional view of a magnetic disk device;
FIG. 4 is a plan view of the disc cap, and FIG. 5 is a partial sectional view showing details of the disc mounting portion. In the figure, (4) is a spindle motor, (7a) to
(7 is the disk, (8a) and (8c) are the spacers, (c) is the knob, the handle is the compression member, (e) t (40a)
) to (40C) are spacing members. In addition, in the figures, the same symbols indicate the same or equivalent parts.

Claims (1)

[Claims] A rotating member that is rotationally driven by a rotational drive device, and a disk that is provided with a spacing member made of an elastic material on at least one surface and is mounted such that one surface abuts the rotating member directly or through the spacing member. and a disk device including a compression member provided on the rotating member and compressing the spacing member by contacting the other surface of the disk directly or via the spacing member.