JPS62146461A - Magnetic disk pressing mechanism for magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To prevent the inner peripheral part of a magnetic disk from the generation of a flaw due to a stabilizing plate by sticking a soft material which does not hurt the magnetic disk in spite of slidable contact with the magnetic disk to the most inside part of the stable plate in the radius direction of the magnetic disk. CONSTITUTION:When the magnetic disk 11 is supported by a center hub 13 and rotated by a spindle motor 12, the largest floating height h0 is obtained on the center part in the radius direction by an air flow due to the rotation of the magnetic disk 11, but the most outside part and most inside part of the stabilizing plate 15 are floated only by a slight height because of the horizontal leakage of the air flow or the magnetic disk 11 is contacted with the plate 15. Since the most inside part of the plate 15 especially presses the magnetic disk 11 downward, the bending rigidity and floating force are offset each other and the plate 15 may be often contacted with the magnetic disk 11. However, the soft materials 20 are stuck to the most inside and outside parts of the plate 15 and the magnetic disk 11 is slidably contacted with only the soft materials 20, so that the magnetic disk 11 is not damaged.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD The present invention relates to a magnetic recording and reproducing apparatus for recording and reproducing data on and from a flexible magnetic disk, and more particularly to a magnetic disk pressing mechanism that presses a magnetic disk against a magnetic head.

"Prior Art and its Problems" In the camera field, this type of magnetic recording/reproducing device is used in electronic still cameras that convert video signals into electrical signals and store them. In this device, in order to ensure that the magnetic disk comes into contact with the magnetic head, a stabilizing plate is located on the opposite side of the magnetic head, and the stabilizing plate presses the magnetic disk against the magnetic head. What about this stabilizer?
There is a type that directly presses the back of the head, and there are four parts that correspond to the magnetic head, and by pressing the magnetic disk on the side edge of the back of the magnetic head, the bending rigidity of the disk is used to create a magnetic disk. An indirect press type is known, and the latter indirect press type is used in electronic still cameras.

4 to 9 are diagrams for explaining the structure and problems of this conventional indirect press type. As shown in FIGS. 4 and 5, the support hole 11a at the center of the magnetic disk 11 is connected to the center hub 11 of the spindle motor
It is supported by and rotates. A magnetic head 14 and a stabilizing plate 15 are located on the front and back sides of the magnetic disk 11.
corresponds to the moving direction of the magnetic head 14. A recess 16 is formed oriented in the radial direction of the magnetic disk 11.

The tip of the stabilizer plate 15 in the radial direction of the magnetic disk is a pressing surface 17 that contacts the magnetic disk 11. This pressing surface 17 suppresses vibrations when the magnetic disk 11 runs (rotates), and acts on each track. The magnetic helad 14 is brought into stable contact.

The above magnetic recording/reproducing device, as shown exaggerated in the figure,
The magnetic disk pressing surface 15a of the stabilizing plate 15 is brought into contact with the magnetic disk 11 to bend the magnetic disk 11 into the recess 16, and due to its rigidity, recording and reproduction are performed while the magnetic disk 11t is in contact with the magnetic head 14. At this time, the upper surface of the magnetic disk 11 supported by the spindle motor 12 near the support hole 11a and the magnetic disk 1 of the stabilizing plate 15
1, that is, the magnetic disk pressing surface L5a, the lower end 13a of the center hub 13
Therefore, when the dimension B of the upper surface of the magnetic disk 11 has a certain tolerance depending on different magnetic disks 11, the following problem occurs. FIG. 6 shows the dimensional variation due to the tolerance of the magnetic disk 11 in terms of ±B.
Even if the dimensions are determined to be, if the above-mentioned dimension B is different, when the magnetic disk 11 is considered as a double-supported beam, the height of one fulcrum will not be constant as shown by ±B°. Then, the contact pressure between the magnetic disk 14 and the magnetic disk 11 becomes inconsistent, and the contact becomes unstable.

Therefore, as shown in FIGS. 7 and 8, the spindle motor 12 is slightly raised relative to the magnetic head 14 and the stabilizer plate 15, and the dimension of the upper surface of the magnetic disk 11 from the lower surface 13a of the center hub 13 is 18'. An apparatus has been proposed in which the size of the upper surface of the magnetic disk 11 from the magnetic disk pressing surface 15a of the stabilizing plate 15 can be ensured even with a tolerance of . According to this device, when the magnetic disk 11 is considered as a beam supported on both sides, as shown in FIG.
Center hub 13 (7i disk 11 support hole 11a
) moves up and down, fulcrums 17s and 18s are formed on the outermost pressing surface 17 and the innermost part 18 of the stabilizer plate 15, respectively. Therefore, the deflection iE of the magnetic disk 11 due to the two fulcrums 17s, 18s and the magnetic head 14 is constant regardless of the type of the magnetic disk 11, so the problem of unstable contact pressure is avoided.

However, in this device, the following problem arises. FIG. 9 is a sectional view taken along line IX-IX in FIG. 4.1. When the magnetic disk 11 rotates, the stabilizer plate 15
It floats with respect to the magnetic helad 14 between the holding surface (outermost part) 17 and the innermost part 18. However, at the holding surface 17 and the innermost portion 18, the flying height of the magnetic disk 11 with respect to the magnetic helad 14 becomes small due to lateral leakage of airflow. That is, even if a flying height of ho can be secured at the radial center of the magnetic disk 11, at the holding surface 17 and the innermost portion 18, the flying height is hl,
The magnetic disk 11, which can only secure a flying height of h2, especially near the innermost part 18 of the stabilizer 15, tends to move away from the stabilizer 15 due to the levitation near the center in the radial direction, but the bending rigidity of the magnetic disk 11 itself To counteract this, the overall flying height cannot be secured. In particular, in this part, the contact between the magnetic disk 11 and the stabilizer 15 is close to a line contact or a point contact, which causes scratches on the magnetic disk 11 and the stabilizer 15, which increases the frequency jitter of the recording/reproduction signal. cause it to happen.

OBJECTS OF THE INVENTION The present invention aims to solve the above-mentioned problems with conventional magnetic recording and reproducing devices, and to provide a device in which the stabilizer plate does not damage the magnetic disk.

``Summary of the Invention'' The present invention was made based on the fact that conventional stabilizers are made entirely of hard and smooth materials for the purpose of stable running of magnetic disks. The part of the stabilizer plate that is likely to come into contact with and damage the magnetic disk, that is, at least the innermost surface of the stabilizer plate in the radial direction of the magnetic disk, facing the magnetic disk.
It is characterized by a soft material attached.

"Embodiments of the Invention" The present invention will be described below with reference to illustrated embodiments. 1 to 3 show an embodiment of the present invention, and the same parts as in the conventional device are given the same reference numerals. The soft material 2o according to the present invention is attached to the innermost and outermost parts of the magnetic disk 11 of the stabilizer plate 15 in the radial direction, and its lower end faces the magnetic disk 11. In FIG. 2, the four parts 16 formed on the stabilizing plate 15 are passed through in the radial direction of the magnetic disk 11, and the outer part is closed by a soft material 20 on the outer side. It has a machine part with surface 17. At the inner end of the recess 16,
No soft material 20 is attached.

Further, the concave portion 16 shown in FIG. 3 is closed on the outside in the radial direction of the magnetic disk, and a holding surface (closed portion) 17 is formed on the outside as in the conventional device. In this example, the soft material 2G is also attached to the edge portion of the inner end of this pressing surface 17. The other parts are the same as in FIG. 2.

As the soft material 20, a material that does not damage the magnetic disk 11, such as nonwoven fabric or felt, can be used.

The device with the above configuration has a magnetic disk 1 in the center hub 13.
When the magnetic disk 1 is supported and rotated by the spindle motor 12, the largest flying height ha is obtained at the center in the radial direction due to the air flow caused by the rotation of the magnetic disk 11, as in the conventional device. At the outermost portion and the innermost portion, due to lateral leakage of airflow, the magnetic disk 11 floats only slightly or the magnetic disk 11 and the stabilizing plate 15 come into contact with each other. In particular, since the magnetic disk 11 is pressed downward at the innermost portion of the stabilizing plate 15, the bending rigidity of the magnetic disk 11 and the floating blade often cancel each other out, causing contact and sliding. However, in the present invention, the innermost and outermost parts of the stabilizer plate 15 are made of soft material 2.
Since the soft material 20 is attached to the soft material 20, the magnetic disk 11 comes into contact with and slides on this soft material 20, so that the magnetic disk 11 is not scratched.

``Effects of the Invention'' As described above, the present invention provides a magnetic recording/reproducing device in which the innermost part of the stabilizing plate that may come into contact with the magnetic disk is prevented from damaging the magnetic disk even if the plate contacts and slides. Since the soft material is attached, it is possible to prevent scratches on the inner peripheral portion of the magnetic disk caused by the stabilizing plate, and to prevent frequency jitter.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a magnetic disk pressing mechanism of a magnetic recording and reproducing apparatus according to the present invention, and FIGS. 2 and 3 are perspective views showing embodiments of a stabilizer plate to which a soft material is attached according to the present invention, respectively. 4 is a sectional view taken along the line IV-IV in FIG. 5, showing an example of a conventional magnetic disk pressing mechanism, FIG. 5 is a sectional view taken along the line V-v in FIG. 4, and FIG. is a skeleton diagram for explaining the problems in the conventional device shown in FIGS. 4 and 5, FIG. 7 is a vertical sectional view showing an example of another conventional magnetic disk pressing mechanism, and FIG. A skeleton diagram showing the state of deformation of the magnetic disk in the device, FIG.
FIG. 6 is a sectional view taken along line IX-IX in FIG. 5, illustrating a problem with the device shown in the figure. DESCRIPTION OF SYMBOLS 11... Magnetic disk, 12... Spindle motor, 13... Center hub, 14... Magnetic head, 1
5... Stabilizer plate, 16... Concave portion, 17... Holding surface (
outermost part), 18... innermost part, 2o... soft material. Patent Applicant: Asahi Optical Industry Co., Ltd. Agent Kunio Miura Shigeru Matsui Figure 1 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9

Claims (4)

[Claims] (1) On the front and back sides of a flexible magnetic disk, a magnetic head for recording and reproducing data on the magnetic disk and a stabilizing plate having a concave portion in the corresponding part of the magnetic head are arranged, and the stabilizing plate allows the magnetic disk to be In a magnetic disk pressing mechanism of a magnetic recording and reproducing device that is brought into pressure contact with a magnetic head, a soft material that does not damage the magnetic disk even if it comes into contact and sliding contact with the magnetic disk is attached to at least the innermost part of the magnetic disk in the radial direction of the stabilizer plate. A magnetic disk pressing mechanism for a magnetic recording/reproducing device characterized by: (2) The magnetic disk pressing mechanism of a magnetic recording and reproducing device according to claim 1, wherein the soft material is also attached to the outermost part of the magnetic disk in the radial direction of the stabilizer. (3) In claim 1 or 2, the recess of the stabilizer plate penetrates the magnetic disk in the radial direction, and the outermost part of the recess is closed by a soft material. The device's magnetic disk pressing mechanism. (4) In claim 1 or 2, the concave portion of the stabilizer plate is closed on the outside in the radial direction of the magnetic disk, and the edge portion of the closed portion is also attached with a soft material. A magnetic disk pressing mechanism of a recording/reproducing device.