JPH0664051A - Manufacture of synthetic resin ball containing metallic ball and its manufacturing apparatus - Google Patents

Abstract

PURPOSE:To easily position a metallic ball at the center of a synthetic resin ball thereby to reduce manufacturing costs remarkably, by heating the synthetic resin ball with high frequencies in the state where the centrifugal force is impressed to the ball, and cooling the ball afterwards. CONSTITUTION:A predetermined number of track balls 11 involving metallic balls 22 are supplied onto a bottom part 10a of a rotary disc 10 by injection molding. When a motor 12 is driven to rotate tame rotary disc 10, the track balls 11 at the bottom part 10a are moved to a peripheral wall 10b by the centrifugal force. The track balls 11 roll over while rotating along the peripheral wall 10b, so that coil driving devices 16a, 16b are concurrently driven. As a result, a heating coil device 14 is descended and stopped in a predetermined position. At the same time, a high frequency generating device 21 is activated to feed a predetermined high frequency current to the heating coil device 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a synthetic resin sphere containing metal balls and an apparatus for manufacturing the same, and is particularly suitable for use in a track ball or the like having a metal ball in its center.
The present invention relates to a synthetic resin sphere manufacturing method and a manufacturing apparatus thereof.

[0002]

2. Description of the Related Art Conventionally, an XY coordinate input device using a track ball (hereinafter simply referred to as an input device) has been used as an input device for a computer or the like. This input device is constructed as shown in FIG. That is, the input device 1 has a recess 2a formed in the upper surface of the housing 2 and a track ball 3
Is rotatably arranged, and the movement of the track ball 3 is detected by a rotation position detecting device (not shown), and the signal is input to a computer or the like via a lead wire 4.
As shown in FIG. 6, the track ball 3 is formed by covering a metal ball 5 with a synthetic resin layer 6 and is rotatably supported by a support base 7. The track ball 3 is rotated by touching the upper surface with a hand. To be made.

By the way, the track ball 3 is molded, for example, by injection molding.
It is extremely difficult to position the metal ball 5 at the center G of the track ball 3, and the eccentricity of the metal ball 5 is likely to occur. Due to this eccentricity, there is a problem that it becomes difficult to perform a delicate input operation required for the input device 1. Therefore, as a method for eliminating such eccentricity of the metal ball, for example, Japanese Patent Publication No.
The manufacturing method shown in 8-38089 is known.

In this manufacturing method, a part of the spherical recess having the same diameter as the metal ball to be contained, a part of the spherical recess having the same diameter as the ball when completed, and the intermediate depth of both recesses are provided. The first step of molding the semi-finished product by placing the metal sphere in the cavity having the concave portion, and molding the semi-finished product, and the other cavity having the spherical concave portion having the same diameter as the ball at the time of completion. In the second step, the semi-finished product is placed and a synthetic resin is injected to mold a synthetic resin sphere.

[0005]

However, this manufacturing method has the problems that the manufacturing cost of the synthetic resin spheres is significantly increased and that quality troubles are likely to occur. That is, a semi-finished product having a band or the like as a holding portion is produced in the first step, and is molded into a synthetic resin sphere in the second step, so that the structure of the die cavity becomes complicated and the die cost is reduced. As a result, the cost for manufacturing one synthetic resin sphere increases as a whole because the molding time of the synthetic resin sphere becomes longer and the like. In addition, since the molding process is performed twice, a joint portion is generated, and a quality trouble is likely to occur due to a difference in color at the portion, a step, and the like, and a subtle rotation operation is required. However, it is difficult to apply it to, for example, the track ball of the above-mentioned input device.

The present invention aims to solve the above-mentioned problems, and can reduce the manufacturing cost, and can obtain a high quality synthetic resin sphere with less eccentricity of the metal sphere. The present invention provides a method of manufacturing a filled synthetic resin sphere and a manufacturing apparatus thereof.

[0007]

In order to achieve such an object, a method for producing a synthetic resin sphere of the present invention is such that a centrifugal force is applied to a synthetic resin sphere formed of synthetic resin having metal balls inside. It is characterized by comprising a first step of high-frequency heating in a heated state and a second step of cooling the heated synthetic resin sphere. Further, in the synthetic resin sphere manufacturing apparatus of the present invention, there is provided a rotating disk having a wall surface on the outer peripheral portion thereof on which the synthetic resin sphere abuts and moves, a rotating disk drive means for rotating the rotating disk, and the rotating disk. And a high-frequency current supply means for supplying a high-frequency current to the heating coil.

[0008]

In the method and apparatus for producing a synthetic resin sphere of the present invention, a synthetic resin sphere containing metal spheres is molded by, for example, injection molding without concern for the position of the metal spheres. Is placed on a rotating turntable, and a heating coil connected to a high-frequency current supply means is arranged in a portion where the synthetic resin sphere is rotating.
The synthetic resin sphere is rotated along the peripheral wall of the rotating disk by centrifugal force, and at the time of this rotation, the metal sphere inside is induction-heated and the synthetic resin layer around the metal sphere is melted. In this state, since the synthetic resin sphere rolls while rotating on its own axis, the metal sphere is focused on the center of the sphere. Then, if this sphere is cooled by, for example, an air cooling device, a synthetic resin sphere having a metal sphere at the center can be obtained.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. 1 and 2 are a sectional view and a plan view of a manufacturing apparatus according to the present invention. In the figure, a rotating disk 10 includes a bottom wall 10a formed in a shallow pot bottom shape into which a track ball 11 is inserted, and a peripheral wall 10 formed on the outer circumference.
b and. A drive shaft 13 of the motor 12 is connected to the center of the bottom wall 10a, and a heating coil device 14 is arranged on the peripheral wall 10b. The heating coil device 14 is arranged over the entire circumference of the peripheral wall 10b of the rotary disk 10, and is connected to the coil driving devices 16a and 16b at two points on the diagonal line via the holding plates 15a and 15b. There is.

The heating coil device 14 is constructed as shown in FIG. That is, the copper pipe has a plurality of heating coils 17, 18 ...
The heating coils 17, 18 ...
They are connected by 20a ... Further, the heating coil 17 includes the bending portions 17a and 17b and the connecting portions 17c and 1c.
7d, and one ends of the connecting portions 17c and 17d are connected to the connecting members 19a and 20a. The peripheral wall 10
The other heating coils arranged in b are also heating coils 17, 1
The configuration is exactly the same as that of No. 8 and the description thereof is omitted.

The connecting portion 17c of the heating coil 17 is
17d and a connecting portion of the heating coil 17 and a heating coil (not shown) located on a diagonal line are connected to the holding plate 15a,
It is fixed by brazing to 15b. Further, the connecting members 19n and 20n of the heating coil at the final end are the high frequency generator 2
1 (see FIG. 1), and the other end of the hose whose one end is connected to a cooling water supply device (not shown) while being electrically connected to the output terminal of FIG. It is connected. Each heating coil of the heating coil device 14, for example, the heating coil 17 is connected to the track ball 1.
In the state where 1 is in contact with the peripheral wall, the curved portions 17a and 17b located on both sides of the track ball 11 and the center G of the ball 11 are arranged so as to have the same distance.

Next, a method of manufacturing the track ball 11 by the above manufacturing apparatus will be described. First, a trackball containing a metal ball 22 (see FIG. 4) by injection molding.
A predetermined number of the balls 11 are put on the bottom portion 10a of the rotating disk 10. Then, when the motor 12 is driven to rotate the rotary disk 10, the centrifugal force generated by the rotation of the rotary disk 10 causes the track ball 11 located at the bottom portion 10a to move to the position shown in FIG.
It moves toward the peripheral wall 10b as indicated by the arrow. The track ball 11 rolls along the peripheral wall 10b while rotating, and in this state, the coil drive device 16a,
16b are simultaneously operated to lower the heating coil device 14 and stop it at a predetermined position, and the high frequency generator 21 is operated to supply a predetermined high frequency current to the heating coil device 14. At the same time as the supply of the high frequency current, the cooling water is supplied into the pipe of the heating coil device 14 to suppress the heat generation of the heating coils 17, 18 ...

When a high-frequency current is supplied to the heating coils 17, 18, ..., The metal balls 22 of the track ball 11 are heated, and the heat of the metal balls 22 melts the synthetic resin layer 23 around them. become. And in this state,
Since the track ball 11 rolls along the peripheral wall 10b while rotating as shown in FIG. 4, the metal ball 22 is at a certain distance from the outer surface of the track ball 11, that is, the ball 1.
It will focus on the center G of 1.

Further, since the distance between the center G of the rolling track ball 11 and the curved portions of the heating coils arranged on both sides of the ball 11 is set to be the same, high frequency heating is performed. In the state where the metal ball 2 is
2 will be pulled together and will be located in the center G of the ball 11. The melting range of the synthetic resin layer 23 around the metal sphere 22 can be regulated by the condition of the high frequency current supplied to the heating coil device 14. Therefore, for example, if the degree of eccentricity of the metal sphere 22 during injection molding is checked by a sampling check or the like, and the condition of the high frequency current is set according to the degree, it is possible to prevent the synthetic resin layer 23 from unduly melting. .

After a lapse of a predetermined time, the coil driving devices 16a and 16b are operated to raise the heating coil device 14, and thereafter the rotation of the rotary disk 10 is stopped. Then, the heated track ball 11 is attached to the rotary disc 1
It is taken out from 0 and cooled under a predetermined condition, for example, by an air cooling device (not shown).

As described above, according to the above-described embodiment, the track ball 11 including the metal balls 22 is attached to the rotary disk 10 and the track ball 11 is rotated.
In order to heat the ball 11 at a high frequency while rolling the ball 11 along its peripheral wall 10b, the metal ball 22 is positioned at the center G of the ball 11 while the track ball 11 is rolling. Become. Therefore, it is not necessary to pay attention to the position of the metal ball 22 at the time of injection molding of the track ball 11, the molding time of the ball 11 can be shortened, and a complicated mold or the like is also unnecessary.

Further, by appropriately setting the high-frequency current, the eccentricity of the metal ball 22 can be corrected in a short time, and if it is properly connected to the feeding device, the cooling device, etc. of the track ball 11, The manufacturing process can be automated. As a result, the manufacturing cost of the track ball 11 can be significantly reduced as a whole. Furthermore, a high-quality track ball 1 with less eccentricity of the metal balls 22
1 can be obtained, and if this track ball 11 is used in the input device 1 as shown in FIG. 7, a delicate input operation becomes possible and an accurate XY coordinate input operation is performed. be able to.

The coil driving devices 16a and 16 in the above embodiment are not always necessary. For example, the track ball 11 is preliminarily arranged along the peripheral wall portion 10b, and the heating coils 17, 18 ... Are also preliminarily arranged. Even if the rotary disk 10 is rotated, it is clear that the same effect as the above embodiment can be obtained. Further, in the above embodiment, the rotating disk 10 is rotated on a horizontal plane, but it may be rotated on a vertical plane or an inclined plane. Furthermore, as shown in FIG.
By disposing a plurality of protrusions 24, 25 on the peripheral wall 10b portion, the rotation of the track ball 11 becomes better, and the focusing of the metal ball 22 on the center G can be promoted.

Further, in each of the above-mentioned embodiments, one heating coil device 14 is arranged all around the rotary disk 10,
The heating coil device 14 may be divided into a plurality of parts, or the heating coil device 14 may be partly arranged on the peripheral wall 10b of the rotating disk 10. Further, in the above embodiment, the magnets are arranged at the inner and outer target positions of the peripheral wall 10b of the rotating disk 10,
The magnetic force of this magnet may be used to attract or repel the metal ball 22 to the center of the trackball 11.

Furthermore, in the above embodiment, the track ball was described as the synthetic resin sphere, but
The present invention is not limited to this, and can be applied to all other synthetic resin spheres containing metal spheres. Further, it is needless to say that the configuration and driving of the rotary disk, the rotating method, the shape and driving method of the heating coil device, the cooling method, etc. are merely examples and can be appropriately changed without departing from the scope of the present invention.

[0021]

As described in detail above, according to the method for producing a synthetic resin sphere containing metal balls and the apparatus for producing the same, according to the present invention,
High frequency heating in a state where centrifugal force is applied to synthetic resin spheres,
Since the metal sphere can be easily positioned at the center position of the synthetic resin sphere simply by cooling it, the manufacturing cost can be greatly reduced and high quality synthetic resin sphere can be easily obtained. Produce the effect of.

[Brief description of drawings]

FIG. 1 is a sectional view of a manufacturing apparatus according to the present invention.

FIG. 2 is a plan view of the same.

FIG. 3 is a perspective view of the main part.

FIG. 4 is a perspective view for explaining the same action.

FIG. 5 is a perspective view of an XY coordinate input device to which the present invention can be applied.

6 is a cross-sectional view of the main part of FIG.

[Explanation of symbols]

 3, 11: Track ball 5, 22: Metal sphere 6, 23: Synthetic resin layer 10: Rotating disk 10b: Peripheral wall 12: Motor 14: Heating coil device 17, 18 ...: Heating coil 21: High frequency generation apparatus

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] June 15, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction content]

[Document name] Statement

Title: Method and apparatus for manufacturing synthetic resin spheres containing metal balls

[Claims]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a synthetic resin sphere containing metal balls and an apparatus for manufacturing the same, and is particularly suitable for use in a track ball or the like having a metal ball in its center.
The present invention relates to a synthetic resin sphere manufacturing method and a manufacturing apparatus thereof.

[0002]

2. Description of the Related Art Conventionally, an XY coordinate input device using a track ball (hereinafter simply referred to as an input device) has been used as an input device for a computer or the like. This input device is constructed as shown in FIG. That is, the input device 1 has a recess 2a formed in the upper surface of the housing 2 and a track ball 3
Is rotatably arranged, and the movement of the track ball 3 is detected by a rotation position detecting device (not shown), and the signal is input to a computer or the like via a lead wire 4.
As shown in FIG. 6, the track ball 3 is formed by covering a metal ball 5 with a synthetic resin layer 6 and is rotatably supported by a support base 7. The track ball 3 is rotated by touching the upper surface with a hand. To be made.

By the way, the track ball 3 is molded, for example, by injection molding.
It is extremely difficult to position the metal ball 5 at the center G of the track ball 3, and the eccentricity of the metal ball 5 is likely to occur. Due to this eccentricity, there is a problem that it becomes difficult to perform a delicate input operation required for the input device 1. Therefore, as a method for eliminating such eccentricity of the metal ball, for example, Japanese Patent Publication No.
The manufacturing method shown in 8-38089 is known.

In this manufacturing method, a part of the spherical recess having the same diameter as the metal ball to be contained, a part of the spherical recess having the same diameter as the ball when completed, and the intermediate depth of both recesses are provided. The first step of molding the semi-finished product by placing the metal sphere in the cavity having the concave portion and molding the semi-finished product, and the other cavity having the spherical concave portion having the same diameter as that of the completed ball In the second step, the semi-finished product is placed and a synthetic resin is injected to mold a synthetic resin sphere.

[0005]

However, this manufacturing method has the problems that the manufacturing cost of the synthetic resin spheres is significantly increased and that quality troubles are likely to occur. That is, a semi-finished product having a band or the like as a holding portion is produced in the first step, and is molded into a synthetic resin sphere in the second step, so that the structure of the die cavity becomes complicated and the die cost is reduced. As a result, the cost for manufacturing one synthetic resin sphere increases as a whole because the molding time of the synthetic resin sphere becomes longer and the like. In addition, since the molding process is performed twice, a joint portion is generated, and a quality trouble is likely to occur due to a difference in color at the portion, a step, and the like, and a subtle rotation operation is required. However, it is difficult to apply it to, for example, the track ball of the above-mentioned input device.

The present invention aims to solve the above-mentioned problems, and can reduce the manufacturing cost, and can obtain a high quality synthetic resin sphere with less eccentricity of the metal sphere. The present invention provides a method of manufacturing a filled synthetic resin sphere and a manufacturing apparatus thereof.

[0007]

In order to achieve such an object, a method for producing a synthetic resin sphere of the present invention is such that a centrifugal force is applied to a synthetic resin sphere formed of synthetic resin having metal balls inside. It is characterized by comprising a first step of high-frequency heating in a heated state and a second step of cooling the heated synthetic resin sphere. Further, in the synthetic resin sphere manufacturing apparatus of the present invention, there is provided a rotating disk having a wall surface on the outer peripheral portion thereof on which the synthetic resin sphere abuts and moves, a rotating disk drive means for rotating the rotating disk, and the rotating disk. And a high-frequency current supply means for supplying a high-frequency current to the heating coil.

[0008]

In the method and apparatus for producing a synthetic resin sphere of the present invention, a synthetic resin sphere containing metal spheres is molded by, for example, injection molding without concern for the position of the metal spheres. Is placed on a rotating turntable, and a heating coil connected to a high-frequency current supply means is arranged in a portion where the synthetic resin sphere is rotating.
The synthetic resin sphere rotates along the peripheral wall of the rotating disk by centrifugal force, and at the time of this rotation, the metal sphere inside is induction-heated, and the synthetic resin layer around the metal sphere melts. In this state, since the synthetic resin sphere rolls while rotating on its own axis, the metal sphere is focused on the center of the sphere. Then, if this sphere is cooled by, for example, an air cooling device, a synthetic resin sphere having a metal sphere at the center can be obtained.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. 1 and 2 are a sectional view and a plan view of a manufacturing apparatus according to the present invention. In the figure, a rotating disk 10 includes a bottom wall 10a formed in a shallow pot bottom shape into which a track ball 11 is inserted, and a peripheral wall 10 formed on the outer circumference.
b and. A drive shaft 13 of the motor 12 is connected to the center of the bottom wall 10a, and a heating coil device 14 is arranged on the peripheral wall 10b. The heating coil device 14 is arranged over the entire circumference of the peripheral wall 10b of the rotary disk 10, and is connected to the coil driving devices 16a and 16b at two points on the diagonal line via the holding plates 15a and 15b. There is.

The heating coil device 14 is constructed as shown in FIG. That is, the copper pipe has a plurality of heating coils 17, 18 ...
The heating coils 17, 18 ...
They are connected by 20a ... Further, the heating coil 17 includes the bending portions 17a and 17b and the connecting portions 17c and 1c.
7d, and one ends of the connecting portions 17c and 17d are connected to the connecting members 19a and 20a. The peripheral wall 10
The other heating coils arranged in b are also heating coils 17, 1
The configuration is exactly the same as that of No. 8 and the description thereof is omitted.

The connecting portion 17c of the heating coil 17 is
17d and a connecting portion of the heating coil 17 and a heating coil (not shown) located on a diagonal line are connected to the holding plate 15a,
It is fixed by brazing to 15b. Further, the connecting members 19n and 20n of the heating coil at the final end are the high frequency generator 2
1 (see FIG. 1), and the other end of the hose whose one end is connected to a cooling water supply device (not shown) while being electrically connected to the output terminal of FIG. It is connected. Each heating coil of the heating coil device 14, for example, the heating coil 17 is connected to the track ball 1.
In the state where 1 is in contact with the peripheral wall, the curved portions 17a and 17b located on both sides of the track ball 11 and the center G of the ball 11 are arranged so as to have the same distance.

Next, a method of manufacturing the track ball 11 by the above manufacturing apparatus will be described. First, a trackball containing a metal ball 22 (see FIG. 4) by injection molding.
A predetermined number of the balls 11 are put on the bottom portion 10a of the rotating disk 10. Then, when the motor 12 is driven to rotate the rotary disk 10, the centrifugal force generated by the rotation of the rotary disk 10 causes the track ball 11 located at the bottom portion 10a to move to the position shown in FIG.
It moves toward the peripheral wall 10b as indicated by the arrow. The track ball 11 rolls along the peripheral wall 10b while rotating, and in this state, the coil drive device 16a,
16b are simultaneously operated to lower the heating coil device 14 to stop at a predetermined position, and the high frequency generator 21 is operated to supply a predetermined high frequency current to the heating coil device 14. At the same time as the supply of the high frequency current, the cooling water is supplied into the pipe of the heating coil device 14 to suppress the heat generation of the heating coils 17, 18 ...

When a high-frequency current is supplied to the heating coils 17, 18, ..., The metal balls 22 of the track ball 11 are heated, and the heat of the metal balls 22 melts the synthetic resin layer 23 around them. become. And in this state,
Since the track ball 11 rolls along the peripheral wall 10b while rotating as shown in FIG. 4, the metal ball 22 is at a certain distance from the outer surface of the track ball 11, that is, the ball 1.
It will focus on the center G of 1.

Further, since the distance between the center G of the rolling track ball 11 and the curved portions of the heating coils arranged on both sides of the ball 11 is set to be the same, high frequency heating is performed. In the state where the metal ball 2 is
2 will be pulled together and will be located in the center G of the ball 11. The melting range of the synthetic resin layer 23 around the metal sphere 22 can be regulated by the condition of the high frequency current supplied to the heating coil device 14. Therefore, for example, if the degree of eccentricity of the metal sphere 22 during injection molding is checked by a sampling check or the like, and the condition of the high frequency current is set according to the degree, it is possible to prevent the synthetic resin layer 23 from unduly melting. .

After a lapse of a predetermined time, the coil driving devices 16a and 16b are operated to raise the heating coil device 14, and thereafter the rotation of the rotary disk 10 is stopped. Then, the heated track ball 11 is attached to the rotary disc 1
It is taken out from 0 and cooled under a predetermined condition, for example, by an air cooling device (not shown).

As described above, according to the above-described embodiment, the track ball 11 including the metal balls 22 is attached to the rotary disk 10 and the track ball 11 is rotated.
In order to heat the ball 11 at a high frequency while rolling the ball 11 along its peripheral wall 10b, the metal ball 22 is positioned at the center G of the ball 11 while the track ball 11 is rolling. Become. Therefore, it is not necessary to pay attention to the position of the metal ball 22 at the time of injection molding of the track ball 11, the molding time of the ball 11 can be shortened, and a complicated mold or the like is also unnecessary.

Further, by appropriately setting the high-frequency current, the eccentricity of the metal ball 22 can be corrected in a short time, and if it is properly connected to the feeding device, the cooling device, etc. of the track ball 11, The manufacturing process can be automated. As a result, the manufacturing cost of the track ball 11 can be significantly reduced as a whole. Furthermore, a high-quality track ball 1 with less eccentricity of the metal balls 22
1 can be obtained, and if this track ball 11 is used in the input device 1 as shown in FIG. 7, a delicate input operation becomes possible and an accurate XY coordinate input operation is performed. be able to.

The coil driving devices 16a and 16 in the above embodiment are not always necessary. For example, the track ball 11 is preliminarily arranged along the peripheral wall portion 10b, and the heating coils 17, 18 ... Are also preliminarily arranged. Even if the rotary disk 10 is rotated, it is clear that the same effect as the above embodiment can be obtained. Further, in the above embodiment, the rotating disk 10 is rotated on a horizontal plane, but it may be rotated on a vertical plane or an inclined plane. Furthermore, as shown in FIG.
By disposing a plurality of protrusions 24, 25 on the peripheral wall 10b portion of the above, the rotation of the track ball 11 becomes better, and the focusing of the metal ball 22 to the center G can be promoted.

Further, in each of the above-mentioned embodiments, one heating coil device 14 is arranged all around the rotary disk 10,
The heating coil device 14 may be divided into a plurality of parts, or the heating coil device 14 may be partly arranged on the peripheral wall 10b of the rotating disk 10. Further, in the above embodiment, the magnets are arranged at the inner and outer target positions of the peripheral wall 10b of the rotating disk 10,
The magnetic force of this magnet may be used to attract or repel the metal ball 22 to the center of the trackball 11.

Furthermore, in the above embodiment, the track ball was described as the synthetic resin sphere, but
The present invention is not limited to this, and can be applied to all other synthetic resin spheres containing metal spheres. Further, it is needless to say that the configuration and driving of the rotary disk, the rotating method, the shape and driving method of the heating coil device, the cooling method, etc. are merely examples and can be appropriately changed without departing from the scope of the present invention.

[0021]

As described in detail above, according to the method for producing a synthetic resin sphere containing metal balls and the apparatus for producing the same, according to the present invention,
High frequency heating in a state where centrifugal force is applied to synthetic resin spheres,
Since the metal sphere can be easily positioned at the center position of the synthetic resin sphere simply by cooling it, the manufacturing cost can be greatly reduced and high quality synthetic resin sphere can be easily obtained. Produce the effect of.

[Brief description of drawings]

FIG. 1 is a sectional view of a manufacturing apparatus according to the present invention.

FIG. 2 is a plan view of the same.

FIG. 3 is a perspective view of the main part.

FIG. 4 is a perspective view for explaining the same action.

FIG. 5 is a perspective view of an XY coordinate input device to which the present invention can be applied.

6 is a cross-sectional view of the main part of FIG.

[Description of Reference Signs] 3, 11: Track ball 5, 22: Metal sphere 6, 23: Synthetic resin layer 10: Rotating disk 10b: Peripheral wall 12: Motor 14: Heating coil device 17, 18 ...: Heating Coil 21: High frequency generator

[Procedure amendment]

[Submission date] September 22, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0015

[Correction method] Change

[Correction content]

After a lapse of a predetermined time, the coil driving devices 16a and 16b are operated to raise the heating coil device 14, and thereafter the rotation of the rotary disk 10 is stopped. Then, the heated track ball 11 is attached to the rotary disc 1
It is taken out from 0, and is cooled by an appropriate method such as air cooling by an air cooling device (not shown) in the state where centrifugal force is applied as in the case of heating.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location // B29L 31:54 4F

Claims (2)

[Claims] 1. A first step of heating a synthetic resin sphere, which is formed of a synthetic resin and has a metal sphere inside, under a high frequency with a centrifugal force applied, and cooling the heated synthetic resin sphere. A second step of
A method for producing a synthetic resin sphere containing metal spheres, comprising: 2. A rotary disk having a wall surface on the outer periphery of which a synthetic resin spherical body abuts and moves, a rotary disk drive means for rotating the rotary disk, and a wall surface of the rotary disk. An apparatus for producing a synthetic resin sphere containing metal balls, comprising: a heating coil; and a high-frequency current supply means for supplying a high-frequency current to the heating coil.