JPS62298924A - Magnetic material coating device for magnetic disk - Google Patents

Abstract

PURPOSE:To minimize the occurrence of turbulent flow having an influence upon film thickness control by placing a clamp claw inward in the radial direction and fitting the inside peripheral part of a disk substrate to the clamp claw. CONSTITUTION:When a wedge member 10 is displaced after a disk substrate 1 is loosely fitted to clamp claws 9 of a clamping device 2, the wedge member 10 is moved along slide parts 8 formed on inside faces of flap part pieces 8, and flap part pieces 8 are bent outward in the radial direction of a main shaft 4 while deforming elastic seal materials 13, and clamp claws 9 are spread and are brought into contact with the inside peripheral face of the disk substrate 1. Flap part pieces 8 having elasticity are bent, and a clamping force corresponding to the extent of this bending is displayed. When the main shaft 4 is rotated and a magnetic material coating liquid is so supplied that this liquid is sprayed out from a coating liquid supply nozzle 3 with a prescribed pressure, the coating liquid is formed into a thin film while going toward the outside peripheral edge part.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Industrial Application Field 1 The present invention relates to a magnetic material coating device for forming a magnetic recording film on the surface of a disk substrate in a magnetic disk manufacturing process. It is something.

[Conventional technology 1] Magnetic disks are made by polishing the surface of a disk substrate made of a circular plate made of aluminum or the like to make it smooth, and then coating the surface with a magnetic material to form a magnetic recording film. The method for forming this magnetic recording film is to apply a magnetic coating liquid to a position near the inner periphery of the disk substrate using a coating liquid supply nozzle while rotating the disk substrate at high speed. A known method is to supply a magnetic material coating liquid to the substrate, and to make the magnetic material coating liquid into a thin film while advancing toward the outer circumferential surface side by the action of centrifugal force due to the rotation of the substrate. The supporting means for rotating the disk substrate at high speed is designed to prevent damage to the surface of the disk substrate and to ensure that the coating liquid drains well at the outer edge portion of the disk substrate. It is necessary to engage the peripheral portion. .

As a support means for supporting the inner circumferential edge of the disk substrate and rotating it at high speed, for example, a clamp unit having male and female clamp members that abuts the front and back surfaces of the inner circumferential edge of the substrate is used. is configured such that the board is held between both clamp members by fitting the board into one clamp member and inserting the other clamp member into the one clamp member,
Using multiple chuck pieces with opposing tapered surfaces,
Each of the chuck pieces is displaced in the radial direction of the substrate, and when chucking the substrate, each of these chuck pieces is expanded radially outward, and the inner peripheral edge corner of the substrate is brought into contact with the tapered surface of the chuck piece. Conventionally, a method has been used in which the chuck is performed by bringing the material into contact with the material.

[Problem to be solved by the invention] Therefore, in order to increase the recording capacity of a magnetic disk and speed up the access time, it is necessary to make the above-mentioned magnetic recording film thinner and to make the film thickness uniform. Is it necessary to
The thinning of the recording film and the uniformity of the film thickness are achieved by controlling the supply amount of the magnetic coating liquid and by rotating the disk substrate at high speed.

By the way, in the disk member support means having the above-mentioned configuration, since the clamp member and the chuck piece protrude from the surface of the disk substrate, when the disk substrate is rotated, the protrusions cause the disk to The air flow generated on the magnetic coating surface of the substrate is disturbed, and this turbulence affects the film thickness of the magnetic coating liquid, making it difficult to form a recording film with a uniform thickness. There will be no. In particular, this turbulent flow increases when the disk substrate is rotated at high speed.Therefore, when the disk substrate is rotated at high speed to promote thinning, this turbulent flow increases the thickness of the magnetic recording film. There are disadvantages such as the inconvenience that the unevenness becomes significantly large.

The present invention has been made in view of the above points.The purpose of the present invention is to minimize the generation of turbulence that affects the film thickness control when forming a magnetic recording film. It is an object of the present invention to provide a magnetic material coating device for a magnetic disk that can form a uniform and extremely thin magnetic recording film by suppressing the amount of magnetic material.

Means for Solving Problem 1 In order to achieve the above-mentioned object, the present invention provides an annular flange section connected to the tip of a cylindrical rotating shaft with an open tip, and from the flange section the above-mentioned At least three clamp claws are formed in the flange portion by forming a slit groove in a portion up to the middle portion of the main shaft, and each clamp claw has a width approximately the same as the inner circumferential surface of the disk substrate. The main shaft is provided with a clamping surface between a clamping position where each clamping claw is deformed and the clamping surface is pressed against the inner peripheral surface of the board and a board mounting position where the board can be inserted. The feature is that the actuating member is engaged with the actuating member to displace the actuator.

[Function] Thus, the clamp claws are positioned on the inside in the radial direction, and held in a state where the inner peripheral portion of the disk substrate can be inserted into the clamp claws, that is, in a board mounting position.

Then, the disk substrate is taken out from the previous process by an appropriate handling means, for example, by clamping its outer periphery, and transported to a working section where magnetic material is applied. Make it fit. Thereafter, the actuating member is actuated to spread the clamp claws of the main shaft to a clamp position in which they are displaced radially outward, and the clamp surface is pressed into contact with the inner surface of the disk substrate. This allows the disk substrate to be clamped by the clamp claws.

Since the width of the clamping surface of the clamp claw is almost the same as the thickness of the disk substrate, the clamp claw forms the same plane as the surface of the disk substrate during clamping, and in this state, the disk Even when the substrate is rotated, the air waves generated on its surface flow undisturbed from the center toward the outer periphery. Therefore, if the magnetic coating liquid is supplied to a position near the inner peripheral edge of the disk substrate by the coating liquid supply nozzle, the magnetic coating liquid will be smoothly spread over the outer circumferential surface by the action of centrifugal force without being affected by airflow. As the magnetic recording film progresses toward the side, it becomes thinner, making it possible to form a magnetic recording film with a uniform thickness on the disk substrate. Since this centrifugal force increases as the rotational speed of the disk substrate increases, in order to make the film extremely thin, it is sufficient to rotate the disk substrate at high speed. Since no turbulence is caused in the airflow, there is no risk that the magnetic recording film will become non-uniform even if the rotational speed of the disk substrate is increased.

[Example] Hereinafter, an example of the present invention will be described in detail based on the drawings.

1 to 3 show a first embodiment of the present invention. In the figures, 1 indicates a disk substrate made of an annular plate made of aluminum or the like, and the disk substrate 1 is connected to a clamping device 2.
During this period, a magnetic coating liquid is supplied from the coating liquid supply nozzle 3 to the surface of the disk substrate 1, thereby forming a magnetic recording film. It has become.

The clamping device 2 has a main shaft 4 formed into a hollow cylindrical shape and made of a metal material with spring properties, and the main shaft 4 is rotated at high speed by a rotation drive means 5 formed of an electric motor or the like. The tip of the main shaft 4 has a thickness approximately equal to that of the disk substrate l.
An annular flange portion 6 having a thickness of 6 slit grooves 7,7. The flap pieces 8, 8 .
... and the clamp claws 9, 9 on the flange portion 6 side. ...is formed. The outer peripheral surface of each clamp claw 9 is a clamping surface 9a, and in order to make surface contact with the inner surface of the disk substrate 1 as much as possible, the clamping surface 9a is designed to be in contact with the inner surface of the disk substrate 1. It has a curved surface shape that approximates the inner peripheral surface of No. 1.

When the flap piece 8 on the main shaft 4 is in a free state, the clamp surface 9a of the clamp claw 9 is at the board mounting position slightly inside the inner peripheral surface of the disk substrate 1, and the flap piece 8 When the clamping claws 9 are displaced radially outward by bending them in the expanding direction, the clamping surfaces 9a are displaced to a clamping position where they can be pressed into contact with the inner circumferential surface of the disk substrate 1. .

In order to expand and deform the flap piece 8 in this way, a truncated conical wedge member 10 is provided inside the main shaft 4 as an operating member.
A sliding portion 8a having a tapered surface that slides into sliding contact with the wedge member 10 is formed on the inner surface of the flap piece 8. This wedge member IO has an operating rod 10a.
The operating rod 10a is connected to a driving member 11, such as a cylinder, for moving the main shaft 4 in the direction of the arrow in FIG. 1 along the axis thereof. Further, a bearing 12 is interposed between the driving member 11 and the operating rod 10a in order to make the operating rod 10a rotatable, and the driving member 11 causes the flap piece 8 to warp outward. It is curved so that the clamp claw 9 can be moved from the board mounting position to the clamp position, and the operating rod 10a can be rotated following the main shaft 4. Furthermore, it prevents adhesion of magnetic coating liquid, etc. to the sliding contact area between the wedge member 10 and the sliding part 8a of the flap piece 8, and prevents abrasion powder, etc. from adhering to the disk substrate 1 due to the sliding contact between the wedge member 10 and the sliding part 8a of the flap piece 8. In order to prevent this from happening and to flatten the distal end surface of the clamp device 2, the portion where the slit groove 5 is formed and the distal opening portion of the main shaft 4 are filled with an elastic sealing material 13 made of silicone rubber or the like. ing.

Furthermore, numeral 14 in the figure indicates a positioning member fitted to the main shaft 4, and the positioning member 14 is a shaft portion 1 formed in a hollow cylindrical shape.
The main shaft 4 of the clamping device 2 is formed by connecting an annular portion 14b protruding radially outward at the tip of the clamping device 4a.
The top can be moved in the axial direction. By bringing the annular portion 14b into and out of contact with the back surface of the clamp claw 9, when the disk substrate 1 is inserted into the clamp claw 9, it comes into contact with the inner peripheral portion of the disk substrate l, and the disk substrate 1 can be positioned at a position where its inner circumferential surface reliably faces the clamp surface 9a of the clamp claw 9.

Note that 15 in FIG. 1 is a handler that chucks the outer peripheral edge of the disk substrate 1 and transfers the disk substrate 1 from the previous process to the magnetic material coating process.

This embodiment is constructed as described above, and its operation will be explained next.

First, the drive member (1) is held in a state in which no external force is applied to the wedge member IO or the clamp claw 9 by protruding it, and the clamp surface 9a of the clamp claw 9 is slightly inward from the inner peripheral surface of the disk substrate 1. In this state, the disk substrate l is chucked by the handler 15 and transferred toward the clamping device 2. Then, the disk substrate 1 is fitted into the clamp claw 9 of the clamp device 2, or when the disk substrate 1 is fitted into the clamp claw 9, there is no contact between the clamp claw 9 and the disk substrate 1. The handler 15 is equipped with a sensor (not shown) to
Detect the center position 1 of the regular clamp device 2 by
The disk substrate 1 is transferred to the clamp device 2 while maintaining a predetermined gap between the disk substrate 1 and the clamp claws 9. During this transfer, since the flange portion 8a of the positioning member 10 is in contact with the back surface of the clamp claw of the clamp device 2, it is necessary to ensure the axial positioning of the disk substrate 1 in the clamp device 2. I'll come.

After the disk substrate 1 is loosely fitted into the clamp claws 9 of the clamp device 2 in this way, when the wedge member 10 is displaced in the direction of the arrow in FIG.
The flap piece 8 moves along a sliding portion 8a formed on the inner surface of the main shaft 4, and the flap piece 8 is bent in a direction radially outward of the main shaft 4 while deforming the elastic sealing material 13. Become.

As a result, the clamp claws 9 are expanded, and the disk substrate 1
It comes into contact with the inner circumferential surface of. Then, when the wedge member 1o is further moved from this state and pressed in a direction to expand the clamp claws 9, the clamp surface 9a of the clamp claws 9 is
At this time, the flap piece 8 having spring properties is bent and exerts a clamping force corresponding to the amount of the bending. Therefore, by adjusting the amount of movement of this wedge member 10 by the drive member 12, the clamping force of the disk substrate 1 by the clamp claws 9 can be adjusted, and the ramp force can be adjusted to an appropriate level according to the rotational speed of the disk substrate 1. During this rotation, there is no risk of vibration or the like occurring in the plate thickness direction. In addition, in this case, when the flap piece 8 is in the free state and in the unclamped state,
By setting the clamping surface 6a to have a slightly smaller diameter than the inner circumferential edge of the disk substrate 1, the flap piece 8 can exert a large ramping force with a small amount of displacement during clamping.

The disk substrate 1 is clamped by the clamp claw 9 as described above.
After clamping the disk substrate 1, the handler 11 is attached to the disk substrate 1.
and move the positioning member 14 backward,
In this state, when the main shaft 4 is rotated by the rotary motion means 5 and the magnetic coating liquid is supplied from the coating liquid supply nozzle 3 by spouting it at a predetermined pressure, this coating liquid is distributed inside the disk substrate 1. The film advances from the peripheral edge toward the outer peripheral edge due to the action of centrifugal force due to the rotation of the disk substrate 1, and becomes a thin film during this time. The coating liquid that has reached the outer peripheral edge is directly scattered by the action of the centrifugal force described above.

The clamp claw 9 in the clamp device 2 has a flat shape with approximately the same thickness as the disk substrate 1! Since the airflow is formed in a circular shape, there is no fear that the air flow generated on the surface of the disk substrate l will be disturbed by the rotation of the disk substrate l, and the airflow is moved from the center along the surface of the disk substrate l to the outer circumference side. Since the flow is constant and stable, when the magnetic coating liquid is supplied to the disk substrate 1, it diffuses from the inner circumferential side to the outer circumferential side of the disk substrate 1 and then progresses to become a thin film. In actuality, there is no inconvenience that the film thickness becomes uneven due to the influence of the air flow. In this way, since the magnetic material can be applied without the risk of air turbulence, the disk substrate 1 can be rotated at high speed to form an extremely thin and uniform magnetic recording film. This makes it possible to improve recording capacity and speed up access time.

Note that when applying this magnetic material, the coating liquid may get around to the inner circumferential side of the disk substrate 1, but the wedge member 9 and the sliding portion 8a of the flap piece 8 are sealed by the elastic sealing material 9. Therefore, foreign matter on these sliding contact surfaces may get mixed in, or conversely, dust generated during the sliding operation between the wedge member 10 and the sliding portion 8a may be attached to the disk substrate l. There's no fear.

When the formation of the magnetic recording film on the disk substrate 1 is completed as described above, the disk substrate 1 is transported to the next process by an appropriate handler that supports the outer peripheral surface, etc., or at this time, the wedge member 9 is By displacing it in the opposite direction to the aforementioned operating direction, the flap piece 8 returns to its free state due to its spring properties, and the clamp claw 9 returns to the unclamped state I.
8. Displaced to.

In addition, in the above-mentioned embodiment, a configuration in which six flap pieces are provided on the main shaft 4 is shown, but this is based on convenience in manufacturing, and three points on the inner circumference of the disk substrate l are supported. For this purpose, at least three should be provided. Furthermore, when the disk substrate l is fitted into the clamp piece 8, its positioning in the plate thickness direction is as follows:
As shown in FIG.
a' and a clamping surface 9b on the tip side of the stepped wall 9a'.
It may be configured to form '. Further, the actuating member may be formed of a truncated conical wedge member, or may be formed of a wedge member having a spherical shape, for example, or may be formed into a ring shape that fits the main shaft 4, It is also possible to adopt a configuration in which the flap part is in a clamping position for clamping the disk substrate 1 in its free state, and is moved to the board mounting position by displacing the flap part radially inward by the ring-shaped actuating member. .

[Effects of the Invention] As described in detail above, the present invention uses a clamping device that clamps the inner peripheral edge of a disk substrate in a state where its surface is substantially flush with the magnetic material coated surface of the disk substrate. Since the disk substrate is clamped and the magnetic material is applied without rotationally driving the disk substrate, turbulence is generated in the air flow generated on the surface during the magnetic material application process. It becomes possible to form a magnetic recording film that is extremely thin and has a uniform thickness without causing any damage.

[Brief Description of the Drawings] Figures 1 to 3 show a first embodiment of the present invention, in which Figure 1 is a sectional view of the clamping device, Figure 2 is a perspective view thereof, and Figure 3 is a sectional view of the clamping device. The plan view and FIG. 4 are cross-sectional views of a clamp device showing a second embodiment of the present invention. 1: disk substrate, 2: clamp device, 3: coating liquid supply nozzle, 4: main shaft, 6: slit groove, 8: flap piece, 8a: sliding part, 9: clamp claw, 9a: clamp surface,
10: Wedge member.

Claims (2)

[Claims] (1) A magnetic disk in which a magnetic recording film is formed on the surface of an annular disk substrate by supplying a magnetic coating liquid from a coating liquid supply nozzle to the surface of the substrate while rotating the substrate at high speed. In a magnetic material coating device, an annular flange portion is connected to the tip of a cylindrical rotating shaft with an open tip, and a slit groove is formed in a portion from the flange portion to an intermediate portion of the main shaft. At least three clamp claws are formed on the flange portion, each clamp claw is formed with a clamp surface having a width substantially the same as the inner peripheral surface of the disk substrate, and each clamp claw is formed on the main shaft. It is characterized by a structure in which an actuating member is engaged and provided to deform and displace the clamp surface between a clamp position where the clamp surface is pressed against the inner peripheral surface of the board and a board mounting position through which the board can be inserted. Magnetic material coating equipment for magnetic disks. (2) A magnetic material coating device for a magnetic disk according to claim (1), characterized in that an elastic sealing member is filled in the gap between the clamp claws and the open end portion of the main shaft. .