JPH0612663A - Magnetic disk manufacturing method - Google Patents

Abstract

(57) [Summary] [Object] To provide a method of manufacturing a magnetic disk with high production efficiency and an inexpensive magnetic disk manufactured by the manufacturing method. [Structure] A blank assembly is made up of a plurality of simulated blanks that cannot be completely punched out only by making cuts in a magnetic disk substrate material. Productivity is improved by processing this blank assembly as a minimum unit and separating it from the blank assembly after completion of the magnetic disk. [Effects] By processing with the above-described manufacturing method, the production efficiency of a small magnetic disk is improved, and a special jig for holding a blank is unnecessary. Therefore, the completed magnetic disk also becomes inexpensive.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk substrate,
The present invention relates to a method for manufacturing a magnetic disk, and particularly to the shape of a magnetic disk substrate material aimed at improving productivity.

[0002]

2. Description of the Related Art In recent years, the importance of magnetic disk devices, which are external storage devices of computer systems, has been increasing. Furthermore, downsizing has been achieved aiming at further miniaturization by being installed in a laptop type word processor for personal use or a personal computer.
This downsizing has not stopped, and along with this, the size of the magnetic disk, which is a recording medium, is also becoming smaller. Initially, the outer diameter was 356 mm, the inner diameter was 178 mm, and the thickness was 1.9 mm. Diameter 25.4 mm,
An inner diameter of 5 mm and a thickness of 0.3 mm are considered.

However, even if the magnetic disk is miniaturized up to this point, as for the manufacturing method, the method from the beginning, in which a single blank obtained by cutting a substrate material into a desired magnetic disk size is used as a minimum unit, is directly followed. ing.

A sputter disk will be described as an example of a conventional magnetic disk manufacturing method. Inner / outer diameter processing of a blank Surface grinding processing Plating surface polishing processing Texture processing Magnetic film / protective film formation Lubricant film coating protrusion removal processing Disk characteristic inspection process After that, the magnetic disk is completed.

In these processes, there are one in which blanks are held and processed one by one as in the above number, and one in which a plurality of blanks are mounted on a special jig and collectively processed as in the above. In any case,
When a blank is put into a facility or a special jig to be used and taken out after the work is completed, it is carried out one by one by a human or a robot. When handling this blank, it is necessary to hold the inner peripheral end face portion or the outer peripheral end face portion or the inner peripheral end face portion and the outer peripheral end face portion so as to sandwich the inner peripheral end face portion or the outer peripheral end face portion so as not to stain or scratch the magnetic recording surface. .

For this reason, the blank holding portion of the robot has been devised, and a special holding jig has been devised. As a typical example, there is the actual development number 59-107723, but it will be further miniaturized in the future. It is difficult to hold the magnetic disk by the conventional method so as not to come in contact with the magnetic recording surface due to the size limitation.

Further, as means for improving productivity, JP-A-3-66025, JP-A-3-93043, and JP-A-62-62.
There are known examples such as -232726 and Japanese Patent Laid-Open No. 3-8118, but in each case, the minimum unit of processing is one blank, and the manufacturing method is particularly improved for small magnetic disks. Absent.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a method for manufacturing a magnetic disk, which improves the productivity of a small magnetic disk.

Yet another object of the present invention is to provide a method of manufacturing a blank that does not separate from the substrate material during processing and can be easily separated from the substrate material after completion.

Still another object of the present invention is to provide a magnetic disk substrate and a manufacturing method capable of simultaneously forming a magnetic film on a plurality of blanks.

Still another object of the present invention is to provide a magnetic disk which can be manufactured efficiently and inexpensively by using the above-mentioned magnetic disk substrate.

Still another object of the present invention is to provide an inexpensive magnetic disk device using the above-mentioned magnetic disk.

[0013]

In order to achieve the above object, in the present invention, a small-sized magnetic disk blank for which a holding condition is severe is not punched out from a substrate material, but is cut so as to leave one or more connecting portions with the substrate material. A blank is put in, and a plurality of the blanks are put together to be cut into an arbitrary size. This blank assembly is processed in the same manner as a conventional blank, so that a plurality of magnetic disks can be simultaneously completed from one blank assembly.

[0014]

In the blank assembly, unnecessary portions other than the simulated blank serve as holding portions.

Therefore, the holding mechanism of the robot or the like becomes simple.

The connecting portion prevents the simulated blank from being separated from the substrate material by the resistance due to the cutting of the processing tape or the grindstone which is the processing means.

The notch has a shape and a depth such that the simulated blank can be easily separated from the blank aggregate without using a press machine or the like.

[0018]

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a plan view of a substrate material for a magnetic disk. Reference numeral 1 is a substrate material for a magnetic disk. The dummy blank 2 has a shape of a magnetic disk formed by a notch 3.
It is not separated from the substrate material 1 by the connecting portion 4. The blank assembly 5 is a collection of a plurality of dummy blanks 2, cut into the size and shape of the cutting line 6, and put into the production line as a minimum unit. The unnecessary portion 7 is discarded when it is completed as a magnetic disk, but is used as a holding portion while the manufacturing line is being put in.

In this embodiment, eight simulated blanks having a diameter of 32 mm are grouped in a blank aggregate having a diameter of 135 mm, but of course, depending on the size of the magnetic disk to be manufactured,
Further, the size and shape may be arbitrary according to the structure of manufacturing equipment.

2a and 2b are detailed views of the dummy blank 2, FIG. 2a is a plan view, and FIG. 2b is A--A in FIG. 2a.
It is a figure which shows the cross section in a line. The cut 2 cuts the inner peripheral part and a part of the outer peripheral part as shown in the drawing, and is also formed in the thickness direction of the connecting part 4. The notch 8 in the thickness direction is for separating the simulated blank 2 from the blank aggregate 5 by using a simple tool or a machine such as a hand press without requiring equipment such as a press machine.

In the present embodiment, the notch 2 having the illustrated shape
Also, four connecting portions 4 having a width of 1.5 mm are provided, and the depth of the cut 2a in the thickness direction is set to 0.1 mm. Of course, depending on the size of the magnetic disk to be manufactured, and the structure of the manufacturing equipment. Depending on the size and shape, any size may be used.

FIG. 3 is a flow chart showing the manufacturing process of the magnetic disk. The difference between the conventional manufacturing method and the manufacturing method according to the present invention will be described with reference to this drawing.

(1) "Blank Assembly Punching" In the conventional method, a blank is punched from a sheet-like magnetic disk substrate by a press machine, and then the outer diameter and the inner diameter of the blank are machined into specified dimensions by turning and the outer peripheral edge is cut. And chamfer the inner end.

According to the method of the present invention, the blank blank punching step corresponds to the conventional blank punching and inner / outer diameter machining step, in which the blank blank is punched at the same time when the notch is made. At this time, the outside diameter and the inside diameter are punched out to the specified dimensions by the notch, and chamfering is also performed if necessary. Such a processing method can be sufficiently dealt with by the current pressing technology.

In the following steps and thereafter, one blank was conventionally put in the minimum unit, but according to the present invention, one blank aggregate is put in as the minimum unit, and it is handled in the same manner as the conventional blank. Is processed. And since eight simulated blanks are contained in this, productivity will be improved eight times as compared with the conventional one.

In this embodiment, a press machine is used as a method for cutting and punching a blank assembly.
A method using etching is also conceivable.

(2) "Surface grinding process" to "projection removal process" In this process, one blank assembly corresponds to one conventional blank, and the same process is performed. According to this embodiment, it is possible to process a so-called 5.25-inch magnetic disk by the conventional processing method.

(3) "Disc separation" In this step, the simulated blank is obtained by the steps up to this point.
It is a step of separating the magnetic disk from the blank assembly after it is completed as a magnetic disk, which is a step which the conventional manufacturing method does not have.

A blank assembly is installed in a lower mold composed of a portion for holding the inner diameter of each magnetic disk in the blank assembly and a cutting tooth for cutting the connecting portion, and a cutting tooth for cutting the connecting portion. The magnetic disk is separated from the blank assembly by applying a force so as to hold the upper mold holding the grip from above.

Since each magnetic disk has a notch in the thickness direction, it can be easily separated by a force such as a hand press. This work uses a hand press in this embodiment, but of course tools such as pliers may be used, or dedicated equipment may be used.

(4) "Disk characteristic inspection" The electromagnetic conversion characteristics and error defect characteristics of the completed magnetic disk are inspected in the same manner as in the past.

The outer diameter does not become a perfect circle as produced by the conventional method because there is a separated part, but this part is not used as a magnetic recording surface, so there is no problem.

[0033]

According to the present invention, a large number of magnetic disks can be manufactured at a time by the same manufacturing method as the conventional one, so that it is possible to provide an inexpensive magnetic disk with improved production efficiency.

[Brief description of drawings]

FIG. 1 is a plan view of a blank assembly.

FIG. 2 is a view showing a detailed plane and a detailed cross section of the simulated blank.

FIG. 3 is a flowchart showing a manufacturing process of a magnetic disk.

[Explanation of symbols]

 1 ... Substrate material for magnetic disk, 2 ... Simulated blank, 3 ... Notch, 4 ... Connection part, 5 ... Blank assembly, 6 ... Cutting line, 7 ... Unnecessary part, 8 ... Notch in thickness direction.

Claims (6)

[Claims] 1. A blank obtained by punching a sheet-shaped magnetic disk substrate material into an arbitrary size of a magnetic disk, a magnetic disk substrate obtained by subjecting the blank to a surface treatment, and a magnetic disk substrate surface. In a method of manufacturing a magnetic disk having a magnetic film formed by vapor deposition or sputtering, a plurality of blanks are simultaneously processed without punching blanks from the substrate material one by one. Method. 2. The method of manufacturing a blank according to claim 1, wherein notches are formed so as to leave at least one connecting portion with the substrate material. 3. A method for manufacturing a magnetic disk substrate, comprising collecting a plurality of the blanks of claim 2 and punching them out as a blank aggregate, and performing surface processing with the blank aggregate as a minimum unit. 4. A magnetic disk substrate manufactured by the method for manufacturing a magnetic disk substrate according to claim 3. 5. A magnetic disk manufactured by using the magnetic disk substrate according to claim 4. 6. A magnetic disk drive using the magnetic disk of claim 5.