JPH0775851B2 - Deburring method and apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is for removing burrs formed on one surface of the peripheral edge of a center hole of an optical disk, such as a compact disk or a video disk, on which information is optically recorded. Burr removal method and apparatus therefor.

[0002]

2. Description of the Related Art Conventionally, an optical disc A of this type is injection-molded, but its sprue runner B is
The sprue runner B, which is provided at the center of the optical disk, that is, the central hole 1, is punched out by a punch C as shown in FIG. 3, but when the punching is performed, a burr 2 is formed as shown in FIG. Will occur.

When the reflective film is formed on the signal recording surface of the master in the state where the burr 2 is generated, the burr 2 is detached during transportation before the process or during the process. Then, as shown in FIG. 5, it may be in a state of being attached to the signal recording surface. When the reflection film is formed in this state, the burr 2 portion becomes a pinhole 3 as shown in FIG. The signal recorded in the part will not be reproduced correctly.

Therefore, conventionally, after the center hole 1 is formed, the center hole 1 is formed by the vacuum cap D as shown in FIG.
The peripheral edge is sucked to suck the burr 2 and the burr 2 is removed, or, as shown in FIG. 8, cutting is performed with a conical blade E.

[0005]

However, the burr 2 formed by pressing often remains in a state of being connected to the central hole 1, and it is difficult to remove it only by vacuum suction. During the transportation to the next step or during the setting in the next step, it falls off and adheres to the optical disk A, and becomes a pinhole 3 in the step of forming the reflective film.

Also, when cutting with the blade E, the cutting powder 4 scatters as shown in FIG. 8, and the scattered cutting powder 4 is attracted to the optical disk A by static electricity, etc. However, when the reflective film is formed, it often becomes a pinhole 3 and causes an error.

The present invention is intended to solve the above-mentioned problems in removing burrs from holes in a conventional heat-melting resin, and heat-welding burrs generated on the periphery of one surface of the holes. It is an object of the present invention to provide a burr removing method and a device for melting the burr integrally with the peripheral edge of the hole to prevent the burr from adhering to and remaining on the surface of the resin to be melted by heat.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a method for removing burrs for achieving the above-mentioned object. The method is to form a center hole in a heat-melted resin molding by pressing or the like.
The burrs that occur when the tip of the pin has a cone-shaped inclined surface, the molten resin adhesion prevention layer is formed on the surface of the pin, and
Insert the inclined surface of the pin, which is controlled to a predetermined temperature, into the center hole, and remove the burr formed around the one surface of the center hole.
It is characterized in that it is brought into contact with an inclined surface of the pin to be softened by heat and is welded to an inner edge portion of the central hole .

As a device for carrying out the above method, the tip of the resin molding to be heat-melted is in contact with the inlet edge of the center hole of the inclined surface by pressing the inclined surface , and the tip has a diameter smaller than that of the center hole.
A pin formed on a conical slope having a base end having a diameter larger than that of the center hole, and having a molten resin adhesion preventing layer formed on the surface thereof, a heating wire attached to the pin, and the pin. And a temperature sensor for detecting the temperature and controlling the heating wire to a constant temperature .

[0010]

The burr removing method and device of the present invention melt the burr generated by pressing the heated conical surface of the pin against the burr generated on the one peripheral edge of the hole of the resin to be melted by heat. This burr is removed by being melted and integrated into the peripheral edge of one surface of the center hole.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An example for carrying out the method of the present invention for removing burrs generated in the center hole of an optical disk will be described below with reference to FIGS. As shown in FIG. 1, the pin 10 used as the deburring device is formed with a conical slope 11 at the tip, and the slope 11 is coated with an adhesion preventing layer 12 of a molten resin such as fluororesin. The molten thermoplastic resin of the optical disk A is prevented from adhering to the slope 11.

Then, in a portion directly below the slope 11,
The heating wire 13 is wound, and the pin 10 is heated by passing an electric current through the heating wire 13. Further, a temperature sensor 14 is built in the center of the pin 10, and the temperature sensor 14 senses the temperature of the pin. The temperature of 10 is controlled so as to maintain a constant temperature.

Then, the slope 11 of the pin 10 which is kept at a constant temperature is pressed against the surface of the center hole 1 of the optical disc A where the burr 2 is generated.
At the same time, a part of the inner edge portion of the center hole 1 of the optical disc A is melted and formed on the tapered surface 15 as shown in FIG.
Are removed.

When the thermoplastic resin of the disk A is melted by the slope 11, the molten thermoplastic resin is converted into the slope 1.
What is attached to No. 1 and is stretched to form a thread is that the adhesion prevention layer 12 coated on the slope 11 prevents the adhesion and does not form a thread.

The pressure and time for which the pin 10 is pressed against the optical disk A must be changed depending on the type of thermoplastic resin and the temperature of the pin 10. The temperature setting of the pin 10 is set to the glass transition temperature of the resin. When the temperature is set to 20 ° C. higher than Tg, the pressure bonding can be performed with a low pressure.

When acrylic resin is used as the material of the optical disk A, the temperature of the heater 10 is Tg =
Since it is 120 ° C, 120 ° C + 20 ° C = 140
Set to ° C, the weight of the optical disc A, that is, 100
If pressure is applied to the slope 11 of the pin 10 with a pressure of about g,
The welding of the burr 2 and the shaping of the inner edge of the central hole 1 are completed in 0.1 to 1.0 sec.

Therefore, when removing the burrs, the burrs 2 are almost completely removed from the surface of the optical disk A due to the scattering of chips and the imperfect suction, and the pin holes accompanying the burrs 2 are adhered to the surface. Therefore, the signal loss of the optical disc A can be prevented.

Although the above-mentioned embodiments have described the method and apparatus for removing the burr in the center hole of the optical disk, the invention is not limited to the optical disk, and the burr in the hole formed in the heat-melting resin product is removed. It can also be applied to cases.

[0019]

As described above, according to the present invention, the conical slope of the heated pin is pressed against the inner edge of the hole of the heat-melting resin in which the burr remains, so that the burr is moved to the inner edge of the hole. Since burrs can be removed by welding while forming an inclined surface, for example, when applied to an optical disc, there is no loss of signal in the pinhole of the reflection film on the signal recording surface, faithful reproduction is possible, and the inner edge of the center hole is In the molding state, the taper surface can be neatly molded, and therefore, it has an effect of not spoiling the appearance.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a heater deburring process in an example of the present invention.

FIG. 2 is a cross-sectional view of an inner peripheral edge portion of a center hole of an optical disc processed by the above.

FIG. 3 is a cross-sectional view before punch punching in an injection molding state.

FIG. 4 is a cross-sectional view of the punch punching process of the above.

FIG. 5 is a perspective view before a reflective film forming step.

FIG. 6 is a perspective view when a reflective film is formed.

FIG. 7 is a perspective view at the time of vacuum suction for removing burrs.

FIG. 8 is a perspective view during a cutting process for removing burrs.

[Explanation of symbols]

 A optical disk 1 center hole 2 burr 10 pin 11 slope 12 adhesion prevention layer 13 heating wire 14 temperature sensor

Claims (2)

[Claims] 1. A heat-melted resin molding is pressed by a press or the like.
The burrs generated when the center hole is drilled are formed on the surface of the pin having a conical sloped tip with a molten resin adhesion prevention layer formed on the pin and the sloped surface of the pin controlled to a predetermined temperature. A method for removing burrs, which is characterized in that the burrs are inserted into the center hole, and burrs formed around one surface of the center hole are brought into contact with an inclined surface of the pin to be softened by heat and then welded to an inner edge portion of the center hole. . 2. The inlet circumference of the center hole of the heat-melted resin molding
The bevel should be pressed against the edge, and the tip should be smaller than the central hole.
And a heating wire attached to the pin, which is formed on a conical slope having a tip end and a base end having a diameter larger than that of the central hole , and on which a molten resin adhesion preventing layer is formed. A deburring device, comprising: a temperature sensor for detecting the temperature of the pin and controlling the heating wire to a constant temperature.