JPH0329547B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an apparatus for polishing disks, such as coated magnetic disks, used as external storage devices for computers.

Conventionally, this type of polishing device polishes the disk surface by rotating the disk to be polished at a constant angular velocity and scanning the polishing head in a direction perpendicular to the direction of rotation of the disk (hereinafter referred to as the radial direction). However, since the polishing linear velocity on the inner and outer circumferences of the disk is not constant, there has been a drawback that the polishing roughness on the inner and outer circumferences of the disk is different. Furthermore, the polishing speed for the inner and outer circumferences of the disk must be set within the polishing linear speed that provides a polished surface with a roughness greater than the required roughness, and when polishing disks with different outer diameters, the polishing line must cover the polishing width. A speed reset is required,
In addition, when the polishing width is large, it is difficult to determine the polishing linear speed to obtain the desired polished surface over a wide range.

In order to eliminate such drawbacks, it is an object of the present invention to provide a disk polishing device in which the polishing linear velocity on the inner and outer circumferences of the disk to be polished is constant.

According to the present invention, in a disk polishing device that polishes a disk surface by moving a polishing head in the radial direction of the disk while being in pressure contact with a rotating disk to be polished, a rotary table for rotating the polishing head and the disk to be polished is provided. The product of the output signal from the polishing head position detection section, which outputs a signal proportional to the distance from the center, and the output signal from the rotation angular velocity output section, which outputs the rotation angular velocity of the disk to be polished, is the polishing linear velocity of the polishing head. It is possible to realize a disk polishing apparatus having a disk rotation angular velocity control section that controls the rotation angular velocity so that the output is equal to the output of the polishing speed setting section that sets the angular velocity.

Next, embodiments of the present invention will be described in detail using the drawings.

FIG. 1 is a schematic diagram illustrating an example of a polished state of a disk, and FIG. 2 is a block diagram showing the configuration of an embodiment of the present invention. In FIG. 1, a polishing head 1 moves a polishing tape 2 coated with abrasive grains from the inner circumference to the outer circumference while applying a predetermined pressure to the surface of the disk 3, and the head 1' indicated by a broken line is This shows the state before the head is moved. At the time of polishing, the optimum linear polishing speed is first set in the polishing speed setting section 4, and this linear polishing speed is determined from the relationship between the polishing surface roughness and the polishing linear speed. Prior to the start of polishing, the polishing head 1 moves to the innermost circumference, pressurizes the disk 3 at a set pressure, and starts polishing. The polishing linear velocity at this time is determined by the output signal from the polishing head position detection section 5 that detects the polishing head position and the rotational angular velocity output section 7 that provides the rotational angular velocity of the spindle 6.
The disk rotation angular velocity control unit 8 controls the rotation angular velocity so that the product with the output signal from the polishing speed setting unit 4 becomes equal to the polishing linear velocity set in the polishing velocity setting unit 4. That is, the polishing linear velocity is determined so as to satisfy the relationship: polishing linear velocity=polishing head position×disk rotational angular velocity. In this embodiment, an output correction circuit 9 is inserted after the polishing speed setting section 5 to add a required slope to the polishing linear velocity, thereby making it possible to cope with changes in the roughness of the inner and outer circumferences of the disk 3 before polishing. In the figure, 10 is a pressurizing mechanism for the disk 3 of the polishing head 1, 11 is a polishing head movement drive unit, 12 is a rotary table, 13 is a movement stroke of the polishing head 1,
Reference numeral 14 indicates the running direction of the abrasive tape 2, and 15 indicates the rotation direction of the disk 3.

With the above structure, according to the present invention, the polishing linear velocity does not change on the inner and outer peripheries of the disk, and the polished surface roughness can be made the same, which eliminates the conventional problem of polishing on the inner and outer circumferences of the disk. Uneven surface roughness can be resolved. Furthermore, the amount of polishing in the radial direction can be treated as a function of time.
Film thickness shaping in the radial direction of the disk can also be easily performed. Even when the external dimensions of the disk to be polished are changed, there is no need to reset the polishing speed, which was a problem in the prior art, and the polishing roughness can be controlled very easily.

In this embodiment, a coated magnetic disk used for an external storage device of a computer is used as the disk 3, but the same effect can be obtained even if it is applied to polishing the surface of a general disk such as a blank plate before applying a magnetic medium. obtain.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram illustrating an example of a polished state of a disk, and FIG. 2 is a block diagram showing the configuration of an embodiment of the present invention. In the figure, 1 is a polishing head, 2 is a polishing tape, 3 is a disk, 4 is a polishing speed setting section, 5 is a polishing head position detection section, 6 is a spindle, 7 is a rotational angular velocity output section, and 8 is a disk rotational angular velocity control section. ,
9 is an output correction circuit, 10 is a pressurizing mechanism for the disk 3 of the polishing head 1, 11 is a polishing head movement drive unit, 12 is a rotary table, 13 is a movement stroke of the polishing head 1, and 14 is a running direction of the polishing tape 2. , 15 represent the rotation direction of the disk 3, respectively.

Claims (1)

[Claims] 1. A disk polishing device comprising a polishing head, a rotary table on which a disk to be polished is installed, a spindle for rotating the rotary table, and a polishing head movement drive unit for moving the polishing head in the radial direction of the disk to be polished, A polishing head position detection part is connected to the polishing head movement drive part and outputs a signal proportional to the distance from the center of the rotary table to the polishing head, and a polishing head position detection part is connected to the spindle and outputs a signal corresponding to each rotational angular speed of the rotary table. These two output signals are input, and the spindle is controlled and the angular velocity of the rotary table is adjusted so that the product of these two output signals is equal to the signal from the polishing speed setting section. A disk polishing device having a disk rotation angular velocity control section.