JP2001079743A - Device for polishing glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the biased abrasion of a polishing drum and to unify the polishing margin distribution of a glass object by providing a revolution mechanism operating the polishing drum in the direction perpendicular to the rotation axis of the polishing drum and in the axial direction of the rotation axis of the polishing drum. SOLUTION: A motor 38 is driven to rotate a polishing drum 12, and another motor is driven to drive a revolution mechanism 40, thereby the polishing drum 12 is revolved in the plane parallel with the plane of a turntable 16 around a main shaft driving an eccentric shaft while being rotated around its axis 12A by the motor 38, and it polishes the face surface 22A of a glass panel 22 in this state. The polishing drum 12 is operated in the direction X perpendicular to the axis 12A of the polishing drum 12 and in the direction Y of the axial direction of the polishing drum 12, the biased abrasion of the polishing drum 12 is prevented, and the polishing margin distribution of the face surface 22A is unified.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass polishing apparatus for polishing a face surface of a glass panel for a cathode ray tube.

[0002]

2. Description of the Related Art A glass panel for a cathode ray tube, which constitutes an image display portion of a cathode ray tube such as a television or a display, supplies a lump of glass melted at about 1000 ° C. to a female mold and presses it with a male mold. Molded.

In a method of manufacturing a glass panel by pressing, minute sharp point defects or wrinkle-like line defects are easily generated on the face surface of a glass panel used as a screen or an image display portion. The face surface is polished to ensure the optical surface quality.

[0004] Such a method of polishing the surface of the face includes a method of polishing by pressing against a face surface while rotating a cylindrical drum polishing tool made of rubber or felt around a central axis (hereinafter referred to as "drum polishing method"). )It has been known.
The drum polishing method is a method of applying a predetermined internal pressure to a flexible hollow cylindrical drum polishing tool, pressing the drum polishing tool against the face surface of a glass panel, rotating the polishing tool, and forming a slurry having a predetermined hardness and particle size. This is a method in which a polishing agent in the form of a liquid is supplied and polished in the meantime, and is used as a polishing method for a glass panel having a good followability to the face surface and having various curvatures.

[0005] Such a drum polishing method can polish efficiently when the face surface has a single spherical shape formed with one curvature, but has an aspherical shape formed with a plurality of curvatures on the face surface. In this case, the polishing allowance distribution is not uniform over the entire surface of the face, and a part of the drum polishing tool, particularly, a portion corresponding to the edge of the face surface is unevenly worn, so that the service life of the drum polishing tool is shortened. There was a disadvantage.

Therefore, there is a polishing apparatus proposed in Japanese Patent Application Laid-Open No. 9-192959 as a device for making the polishing allowance distribution on the face surface uniform. This polishing apparatus polishes the face surface while reciprocating the drum polishing tool in a direction perpendicular to the rotation axis of the drum polishing tool.Because the followability of the drum polishing tool to the aspheric surface of the face surface is improved, The polishing allowance distribution on the face surface can be made uniform.

On the other hand, as a device for preventing uneven wear of a drum polishing tool, there is a polishing device proposed in Japanese Patent Application Laid-Open No. 9-131657. This polishing apparatus polishes the face surface while reciprocatingly swinging the drum polishing tool in the axial direction of the rotation axis of the drum polishing tool, and can prevent the drum polishing tool from hitting against the edge of the face surface. Uneven wear of the polishing tool can be prevented.

[0008]

However, the polishing apparatuses disclosed in JP-A-9-192959 and JP-A-9-131657 are designed to prevent uneven wear of the drum polishing tool and to make the distribution of the stock removal on the face surface uniform. There was a disadvantage that it could not be achieved at the same time.

Therefore, as an apparatus for solving the above-mentioned drawbacks,
X having an X-direction moving table and a Y-direction moving table
A polishing apparatus that polishes the face surface while moving the drum polishing tool in the XY directions by a Y moving mechanism is conceivable.
However, the XY moving mechanism requires a motor and a moving mechanism for moving each table, and thus has a drawback that the structure of the polishing apparatus is complicated.

The present invention has been made in view of the above circumstances, and has a simple glass polishing structure having a structure capable of simultaneously preventing uneven wear of a drum polishing tool and uniforming a distribution of a stock removal of a glass article. It is intended to provide a device.

[0011]

According to the present invention, in order to achieve the above object, a glass article is placed and fixed on a rotary table surface, and the glass article is rotated on the surface of the glass article while rotating the rotary table. In a glass polishing apparatus for polishing the surface by pressing a cylindrical drum polishing tool, the glass polishing apparatus is provided with a revolving motion mechanism for revolving the drum polishing tool, and the revolving motion mechanism includes an eccentric shaft. And a glass polishing apparatus characterized in that a drum polishing tool revolves around a rotary table surface around a main shaft for driving the eccentric shaft.

According to the present invention, the surface of the glass article is polished while the drum polishing tool is revolved along the rotary table surface around the main shaft for driving the eccentric shaft by the revolving motion mechanism. When the drum polishing tool revolves in this way, the drum polishing tool operates in a direction orthogonal to the rotation axis of the drum polishing tool and in the axial direction of the rotation axis of the drum polishing tool, thereby preventing uneven wear of the drum polishing tool. And uniformity of the polishing allowance distribution of the glass article can be achieved at the same time.

Further, a preferable revolving motion mechanism has a structure including one driving eccentric shaft and two driven eccentric shafts for connecting a fixed portion of the glass polishing apparatus and a supporting portion on which the drum polishing tool is supported. The structure is simpler than that of the XY moving mechanism, and a stable revolving motion can be obtained.

The revolving motion mechanism will be described. If only two or more driving eccentric shafts are mounted, the drum polishing tool revolves without rotating, but the revolving motion mechanism has a complicated structure. A revolving motion mechanism for revolving a drum polishing tool with a drive eccentric shaft is desired. However, if there is one drive eccentric shaft, it is necessary to prevent the drum polishing tool from rotating on its own axis. As a measure to prevent rotation, it can be dealt with by installing a driven eccentric shaft that does not drive, but if the driven eccentric shaft is mounted without considering the mounting position of the driven eccentric shaft, depending on the position where the drum polishing tool starts revolving motion May be locked by dead center.

Therefore, in order to avoid the locking phenomenon, the present invention provides two driven eccentric shafts, and the two driven eccentric shafts are located at positions where the straight line connecting the two driven eccentric shafts and the drive eccentric shaft is not straight. A driven eccentric shaft is arranged. Thus, the revolving motion mechanism of the present invention can avoid the locking phenomenon, and can smoothly revolve the drum polishing tool regardless of the position of the drum polishing tool.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a glass polishing apparatus according to the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a top view showing a polishing apparatus 10 for a glass article, for example, a glass panel for a cathode ray tube (hereinafter referred to as "glass panel") to which the glass polishing apparatus of the present invention is applied, and FIG. FIG. The polishing apparatus 10 shown in these figures includes a polishing section 1 having a drum polishing tool 12.
4 and a table rotating unit 18 having a rotating table 16
And the polishing unit 14 and the table rotating unit 18
They are installed on the same base 20 at predetermined intervals.

The glass panel 22 polished by the drum polishing tool 12 has a face surface 22A formed in an aspherical shape, and is placed and fixed on the surface of the rotary table 16 with the face surface 22A facing upward. Then, the rotary table 16 is rotated at a predetermined rotational speed by a driving force of a motor 24 for rotating the rotary table 16. This rotation speed is preferably in the range of 5 to 100 rpm, and particularly preferably in the range of 10 to 50 rpm. If it is less than 5 rpm, the polishing efficiency is reduced.
If the rotation speed exceeds 100 rpm, it becomes difficult to fix the glass panel 10 to the turntable 16 and a large-capacity motor 24 is required.

The table rotating section 18 comprises two rotating tables 16, 16, a turret plate 26, a motor 24 and the like. The rotary table 16 is a rotary table 16
The turret plate 26 having a larger diameter than the turret plate 26
Are installed with the rotary shaft 28 interposed therebetween. The rotary table 16 has a shaft 30 pivotally supported by the turret plate 26 and is arranged so as to penetrate the turret plate 26. A clutch 32 having an uneven portion is provided below the shaft 30. The clutch 32 is detachably connected to a clutch 36 provided above an output shaft 34 of the motor 24. When the clutch 32 is connected to the clutch 36, the driving force of the motor 24 is changed to the output shaft 34 → the clutch 36 →
The power is transmitted from the clutch 32 to the rotary table 16 via the shaft 30, whereby the rotary table 16 on the left side in FIG. 2 is rotated at the above-described rotation speed.

At this time, the right rotary table 16 in FIG.
Is at a position retracted from the motor 24 and is not rotated, and the glass panel 22 is delivered at this position. That is, the glass panel 22 that has been polished on the left turntable 16 is positioned at the transfer position on the right side by a half-turn operation of the turret plate 26 in a state of being fixedly mounted on the turntable 16. . At this position, the polished glass panel 22 is placed on the turntable 1.
6 and removed from the glass panel 22 before polishing
Is mounted and fixed on the turntable 16. After the glass panel 22 is positioned at the polishing position on the left side of FIG. 2 by the half rotation of the turret plate 26, the clutch 36 of the motor 24 is connected to the clutch 32 of the turntable 16, and the driving of the motor 24 is performed. Polished by the drum polishing tool 12 while being rotated by force.

The polishing section 14 comprises the drum polishing tool 12, a drum motor 38, a revolving motion mechanism 40, an air spring 42, and a drum lifting / lowering cylinder device 44.

The drum polishing tool 12 has bearings 48A, 48B attached to a pair of arms 46, 46 as shown in FIG.
The shafts 12A and 12B at both ends are rotatably supported, and the shafts 12A and 12B are
Is supported in parallel with the surface of Also, the shaft 12
A protrudes laterally from the bearing 48A, and its protruding portion 12A
A pulley 50 is fixed to C. This pulley 50
Is connected via a belt 56 to a pulley 54 attached to the output shaft 52 of the drum motor 38,
When the driving force from the motor 38 is transmitted to the drum polishing tool 12 via the pulley 54 → the belt 56 → the pulley 50, the drum polishing tool 12 is rotated at a predetermined rotation speed. The motor 38 is fixed on a rocking plate 58, and the arms 46 are fixed to the rocking plate 58 via a shaft 60.

The diameter of the drum polishing tool 12 is 300 to 80.
A range of 0 mm is preferred. If it is less than 300 mm, it is difficult to increase the peripheral speed of the drum polishing tool 12, and
This is because if it exceeds mm, the strength of the drum polishing tool 12 with respect to the internal pressure decreases. The length of the drum polishing tool 12 needs to be determined according to the size of the glass panel 22 in order to obtain good followability to the face surface 22A when the drum polishing tool 12 is pressed against the glass panel 22. Assuming that the diagonal diameter of 22 is A and the length of the drum polishing tool 12 is B, the length is set to 1.5A <B <2.5A. At 1.5 A or less, the ability to follow the face surface 22A is insufficient. At 2.5A or more, the amount of deformation of the drum polishing tool 12 when the drum polishing tool 12 is pressed against the glass panel 22 increases, and the drum polishing tool 12 This is because polishing efficiency decreases due to problems such as generation of vibrations due to rotation of.

The rotational speed of the drum polishing tool 12 is 100 to 10
The range of 00 rpm is preferable, and the range of 300 to 800 rpm is particularly preferable. When the rotational speed is less than 100 rpm, the peripheral speed of the drum polishing tool 12 decreases, and the polishing efficiency decreases. When the rotational speed exceeds 1000 rpm, the polishing efficiency decreases due to generation of vibration and the like.

The drum polishing tool 12 has a face surface 22A.
Is preferably made of hollow rubber or felt so as to obtain a good followability with respect to the change in curvature, and is used by applying a predetermined internal pressure. This internal pressure is 0.2-2kg
/ Cm ² is preferable, and 0.4 to 1.2 kg / cm 2
A range of ² is particularly preferred. Is less than 0.2 kg / cm ^2, is because the polishing efficiency by the pressing force deficit is decreased, when it exceeds 2 kg / cm ^2, the face surface 22A
This is because the followability to the curvature of the image is reduced.

On the other hand, the swing plate 58 is supported by a support plate (corresponding to a support portion) 62 via the air spring 42 as shown in FIG. The air spring 42 has a function of absorbing the reaction force from the glass panel 22 transmitted from the drum polishing tool 12 to the rocking plate 58 via the arms 46, 46. That is, the air spring 42 is formed in an airbag shape, and absorbs the reaction force by performing a contracting operation. The swinging plate 58 is swung with respect to the support plate 62 by the contraction operation of the air spring 42, whereby the drum polishing tool 12 satisfactorily follows the face surface 22A. The internal pressure of the air spring 42 is set according to the internal pressure of the drum polishing tool 12 and the like, but is set to 0.5 to 2.0 kg / cm ² in consideration of the followability of the drum polishing tool 12. Is preferred.

Below the support plate 62, a base plate (corresponding to a fixed portion) 64 is arranged.
1, one drive eccentric shaft mechanism 66 and two driven eccentric shaft mechanisms 68, 68 (FIG.
Are disposed at predetermined positions. The orbiting mechanism 40 will be described later.

The base plate 64 is rotatably supported via a shaft 72 on an upper part of a column 70 erected on the base 20.
The base plate 64 is provided with the cylinder device 44 for raising and lowering the drum.
The rod 78 is rotatably connected to the distal end of a rod 74 via a pin 76, and the cylinder 78 of the drum lifting / lowering cylinder device 44 is rotatably connected to a support 70 via a pin 80. Therefore, the drum lifting / lowering cylinder device 4
When the rod 74 of FIG. 4 contracts from the extended state of FIG. 2, the base plate 64 is pulled by the rod 74 and rotates counterclockwise in FIG. With this operation, the drum polishing tool 12 mounted on the base plate 64 moves up and retreats from the glass panel 22.

Next, the revolving motion mechanism 40 will be described. The drive eccentric shaft mechanism 6 constituting the revolving motion mechanism 40
6 includes a main shaft 82 as shown in FIG. 3 and an eccentric shaft 84 eccentric with respect to the main shaft 82 formed integrally with the main shaft 82.

The main shaft 82 is rotatably supported via a bearing 90 on a case 88 fixed to the upper surface of the base plate 64 by bolts 86, while the eccentric shaft 84 is fixed to the lower surface of the support plate 62 by bolts 92. The case 94 is rotatably supported via a bearing 96. The eccentric shaft 84 protrudes upward through a through hole 63 formed in the support plate 62. The output shaft 104 of the motor 102 is connected to the protrusion 85 via a coupling 98 and a speed reduction mechanism 100. Are linked. The motor 102 includes a support plate 62 as shown in FIG.
Is fixed on a motor mounting base 106 provided in the motor.

Therefore, according to the drive eccentric shaft mechanism 66 having such a structure, the rotational force of the motor 102 is controlled by the eccentric shaft 8 shown in FIG.
4, the main shaft 82 is moved to the axis 84A of the eccentric shaft 84.
However, since the main shaft 82 is restricted in eccentric rotation by the base plate 64, the rotational force is transmitted from the main shaft 82 to the eccentric shaft 84. As a result, the eccentric shaft 84 is eccentrically rotated about the axis 82A of the main shaft 82, so that the eccentric rotational force is transmitted to the support plate 62 via the case 94, and thus the support plate 62 is It is revolved around 82A. Accordingly, the drum polishing tool 12 mounted on the support plate 62 is driven to revolve around the axis A substantially perpendicular to the surface of the turntable 16 as shown in FIG. . Then, the rotation of the support plate 62 (the rotation of the support plate 62 about the axis 84A of the eccentric shaft 84) due to the revolving drive of the support plate 62 is prevented by the driven eccentric shaft mechanism 68 of FIG.

The driven eccentric shaft mechanism 68 comprises a main shaft 110, an eccentric shaft 112 and the like. The main shaft 110 is a case 1 fixed to the upper surface of the base plate 64 with bolts 114.
16 is rotatably supported via bearings 118, while
The eccentric shaft 112 is rotatably supported via a bearing 124 on a case 122 fixed to the lower surface of the support plate 62 with bolts 120. The amount of eccentricity a of the shaft 112 of the driven eccentric shaft 112 with respect to the axis 110A of the main shaft 110 is set equal to the amount of eccentricity a of the drive eccentric shaft mechanism 66 shown in FIG.
Thus, the support plate 62 is driven to revolve in a well-balanced manner.

The driven eccentric shaft mechanism 6 configured as described above
As shown in FIG. 6, the reference numerals 8 and 68 are provided at the right position in FIG. 6 with respect to the drive eccentric shaft mechanism 66. The installation location of the drive eccentric shaft mechanism 66 is the position A in FIG. 7, and the installation locations of the driven eccentric shaft mechanisms 68, 68 are the B position and the C position.

With reference to FIG. 7, a description will be given of the cause of the occurrence of the revolution locking phenomenon of the support plate 62 and a measure for preventing the phenomenon.

First, the cause of the occurrence of the revolution locking phenomenon will be described. The shaft 82 of the main shaft 82 of the drive eccentric shaft mechanism 66 will be described.
A and a straight extension line L1 connecting the eccentric shaft 84 and the shaft center 84A.
When only one driven eccentric shaft mechanism (the driven eccentric shaft mechanism at the position B) 68 is disposed above, when the driven eccentric shaft mechanism 68 rotates in the opposite direction when the support plate 62 starts revolving. There is. Thus, the support plate 62 is locked without revolving. This is the cause of the occurrence of the revolution locking phenomenon.

In order to prevent the revolution locking phenomenon,
In the present embodiment, the two driven eccentric shaft mechanisms 68, 68 are arranged at positions where the straight lines connecting the two driven eccentric shaft mechanisms 68, 68 and the drive eccentric shaft mechanism 66 are not straight. In principle, the second driven eccentric shaft mechanism (the driven eccentric shaft mechanism at the position C) 68 may be installed at a position not overlapping with the extension line L1, but at a position very close to the extension line L1, the support plate 62 may be provided. May be locked or adversely affect the operation of revolving start. Therefore, from such a viewpoint, the second driven eccentric shaft mechanism 68 is installed at a position on a line L2 at 63 ° with respect to the extension line L1. In practice, two driven eccentric shaft mechanisms 68, 68 may be installed at 90 ° ± 45 °.

Therefore, in the present embodiment, the support plate 6
Since the two driven eccentric shaft mechanisms 68, 68 are installed at the optimal positions for preventing the revolution lock of the support plate 6,
2 or the revolution locking phenomenon of the drum polishing tool 12 can be reliably prevented.

In this embodiment, the motor 102 for revolving motion is used.
As described above, the support plate 6 is
2, the motor 102 may be set below the base plate 64, for example, and the main shaft 82 may be driven to rotate so that the motor 102 revolves. By doing so, the motor 1
The drive mechanism mainly composed of the orbit 02 is released from the orbital motion, and the orbital motion mechanism can be reduced in weight.

Next, the operation of the polishing apparatus 10 for a glass panel for a cathode ray tube configured as described above will be described.

First, the glass panel 2 before polishing is placed on the turntable 16 located at the transfer position on the upper right side in FIG.
Place 2 and fix. Then, the turret plate 26 is rotated half a turn to position the glass panel 22 at the polishing position on the left side of FIG. At this time, since the drum polishing tool 12 has escaped to the standby position retracted upward by the drum lifting / lowering cylinder device 44, the glass panel 22 is set at the polishing position without being disturbed by the drum polishing tool 12. Thereafter, the clutch 32 on the rotary table 16 side is connected to the clutch 36 on the motor 24 side. Then, the drum polishing tool 12 is moved downward by the drum lifting and lowering cylinder device 44 to press and contact the face surface 22A of the glass panel 22 and set the polishing pressure to a predetermined pressure. Thus, the preparation for polishing the face surface 22A is completed.

Next, the motor 38 is driven to rotate the drum polishing tool 12, and the motor 102 is driven to drive the revolving motion mechanism 40. Further, the glass panel 22 is rotated by the motor 24. Thus, the drum polishing tool 12 is driven by the motor 38 so that the shafts 12A, 12B
While rotating about the axis A in FIG. 4 (corresponding to the main shaft for driving the eccentric shaft in claim 1),
The revolving motion is performed in a plane parallel to the plane, and the face surface 22A is polished in this state.

When the drum polishing tool 12 is revolved as described above, the drum polishing tool 12 is moved to the axis 1 of the drum polishing tool 12.
It operates in the X direction (horizontal direction, see FIG. 1) orthogonal to 2A and 12B and in the Y direction which is the axial direction of the drum polishing tool 12 (actually, it operates in a direction in which the X direction and the Y direction are combined). Therefore, it is possible to simultaneously prevent uneven wear of the drum polishing tool 12 and uniformize the distribution of the stock removal on the face surface 22A.

Further, the revolving motion mechanism 40 of the present embodiment
Is a structure composed of one drive eccentric shaft mechanism 66 and two driven eccentric shaft mechanisms 68, 68, and therefore has a simple structure as compared with an XY movement mechanism having an X-direction movement table and a Y-direction movement table. Accordingly, the overall structure of the polishing apparatus 10 can be simplified.

In the present embodiment, the face surface 2
Although the glass panel 22 whose 2A is formed in an aspherical shape has been described, the glass panel 22 is not limited to this, and may be a glass panel whose face surface is formed in a single spherical shape, or a glass panel whose face surface is flat. But it can be applied.

In this embodiment, the glass panel 22 for a cathode ray tube is exemplified as a glass article. However, the present invention is not limited to this, and any glass article that requires surface polishing can be applied.

[0046]

As described above, according to the glass polishing apparatus of the present invention, the drum polishing tool is rotated by the revolving motion mechanism in the direction perpendicular to the rotation axis of the drum polishing tool and the axis of the rotation axis of the drum polishing tool. , The prevention of uneven wear of the drum polishing tool and the uniformization of the polishing allowance distribution of the glass article can be achieved at the same time.
Since it has a simple structure including two drive eccentric shafts and two driven eccentric shafts, the overall structure of the glass polishing apparatus can be simplified.

[Brief description of the drawings]

FIG. 1 is a top view of a glass panel polishing apparatus for a cathode ray tube according to an embodiment of the present invention.

FIG. 2 is a side view of the polishing apparatus shown in FIG. 1;

FIG. 3 is a cross-sectional view of a drive eccentric shaft mechanism constituting a revolution motion mechanism.

FIG. 4 is an explanatory diagram showing a revolution locus of a drum polishing tool.

FIG. 5 is a cross-sectional view of a driven eccentric shaft mechanism constituting a revolving motion mechanism.

FIG. 6 is an explanatory diagram showing the revolving locus of each eccentric shaft of the drive eccentric shaft mechanism and the driven eccentric shaft mechanism.

FIG. 7 is an explanatory diagram showing an arrangement position of a driven eccentric shaft mechanism with respect to a drive eccentric shaft mechanism.

[Explanation of symbols]

DESCRIPTION OF REFERENCE NUMERALS 10: glass panel polishing apparatus for cathode ray tube, 12: drum polishing tool, 14: polishing section, 16: rotary table, 18
... Table rotating unit, 22 ... CRT glass panel,
22A: face surface, 40: revolving motion mechanism, 66: drive eccentric shaft mechanism, 68: driven eccentric shaft mechanism

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yasunari Ikuta 1-1-10 Kitahonmachi, Funabashi-shi, Chiba F-term in Asahi Glass Co., Ltd. (reference) 3C049 AA03 AA11 AA16 AB06 CA06 CB01 CB03

Claims (2)

[Claims] 1. A glass polishing apparatus for mounting and fixing a glass article on a rotary table surface, and pressing a rotating cylindrical drum polishing tool against the surface of the glass article while rotating the rotary table to polish the surface. In the apparatus, the glass polishing apparatus is provided with a revolving motion mechanism that revolves the drum polishing tool, the revolving motion mechanism includes an eccentric shaft, and the drum polishing device rotates the drum polishing tool around a main shaft that drives the eccentric shaft. A glass polishing apparatus characterized by revolving a tool along a rotating table surface. 2. The revolving motion mechanism includes one drive eccentric shaft and two driven eccentric shafts connecting a fixed portion of the glass polishing apparatus and a support portion on which the drum polishing tool is supported, 2. The glass polishing apparatus according to claim 1, wherein the two driven eccentric shafts are arranged at positions where a straight line connecting the two driven eccentric shafts and the drive eccentric shaft is not straight.