JP2000061795A - Autorotation preventing device of rotary plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent revolution of a rotary plate from being locked by providing driven eccentric shafts on the position where straight lines connecting the driven eccentric shafts with a driving eccentric shaft do not become one straight line. SOLUTION: A polishing table 12 is fixed to a device body 11 through autorotation preventing devices 16, 16. This autorotation preventing device 16 is constituted of a main shaft and a driven eccentric shaft 22 and the like. The eccentric quantity of the shaft axis 63 of the driven eccentric shaft 62 against the axis 61 of the main shaft is set to be equal to the eccentric quantity of a driving eccentric shaft 28 against the main shaft 26 of an eccentric rotational mechanism 14. Hereby, the polishing table 12 is driven to revolve in good balance. The two driven eccentric shafts 62, 62 are arranged on the positions where the straight lines connecting the two driven eccentric shafts 62, 62 with the driving eccentric shaft 28 do not become one straight line, and hence revolution of the polishing table is surely prevented from being locked, As a result, the polishing table 12 can be smoothly driven to revolve under the condition of preventing the autorotation.

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a rotation preventing device for a rotating plate, and more particularly to a rotating plate (grinding table) for rotating a work provided in a polishing device for a glass panel for a cathode ray tube. The present invention relates to a device for preventing rotation. 2. Description of the Related Art In a polishing apparatus of this kind, a glass table for a cathode ray tube is provided by preventing a rotation of a polishing table caused by a revolution driving of the polishing table by a rotation preventing device and performing only a revolving operation of the polishing table. An apparatus for polishing uniformly is known. As an example of the rotation preventing device, the present applicant has proposed a device using a ball joint in Japanese Patent Application No. 10-115347. According to this rotation preventing device, when the polishing table tries to start revolving, it hardly occurs that the polishing table locks and the revolving becomes difficult. Recently, a rotation preventing device using a driven eccentric shaft has been proposed. The driven eccentric shaft has an eccentric amount equal to the eccentric amount of the drive eccentric shaft for revolvingly driving the polishing table, and has substantially the same structure as the drive eccentric shaft, and has a relatively simple structure. In addition, there is an advantage that the polishing table can be stably supported because it is easy to obtain strength in terms of structure. Although the driven eccentric shaft can prevent the rotation with only one shaft,
It is preferable to provide two polishing tables from the viewpoint of stabilizing the revolving operation of the polishing table. However, the anti-rotation device using the driven eccentric shaft is mounted on the polishing table without any consideration of the driven eccentric shaft. Is about to revolve,
There is a disadvantage that the polishing table may lock. The present invention has been made in view of such circumstances, and in a rotation preventing apparatus for preventing rotation of a rotating plate by a driven eccentric shaft, the rotation eccentric shaft is installed at an optimum position by setting the driven eccentric shaft at an optimum position. An object of the present invention is to provide a rotation preventing device for a rotating plate that can prevent revolving lock. In order to achieve the above object, the present invention provides an apparatus for preventing rotation of a rotating plate provided to revolve around a drive eccentric shaft. By providing two driven eccentric shafts having an eccentric amount equal to the amount on the rotary plate, rotation of the rotary plate is prevented, and a straight line connecting the two driven eccentric shafts and the drive eccentric shaft is straight. It is characterized in that the two driven eccentric shafts are installed at positions where they are not required. According to the present invention, since the two driven eccentric shafts are installed at positions where the straight line connecting the two driven eccentric shafts and the drive eccentric shaft is not straight, the revolving lock of the rotating plate is prevented. Can be. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a rotating plate rotation preventing device according to the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a front view including a partial cross section of a glass panel polishing apparatus 10 for a CRT to which a rotation preventing device for a rotating plate according to an embodiment of the present invention is applied. The polishing apparatus 10 shown in FIG. 1 mainly includes a polishing table 12, an eccentric rotation mechanism 14, a rotation preventing device 16,
And a polishing unit 18. The polishing table 12 is provided with two rotation preventing devices 16
(See FIG. 2). The polishing table 12 is formed in a rectangular shape as shown in FIG.
The CRT glass panel 20 is placed on the upper surface. The CRT glass panel 20 is as shown in FIG.
It is placed on the polishing table 12 with the face surface 21 facing upward, and is positioned and held at a predetermined position on the polishing table 12 by positioning members 22 provided on the polishing table 12. As shown in FIG. 1, the eccentric rotation mechanism 14 has a motor 24, a main shaft 26, and a drive eccentric shaft 28 as main components. The motor 24 is supported on a support plate 30 protruding from the side of the apparatus body 11, and is attached to the support plate 30 with its spindle 25 facing downward. The spindle 25
Are arranged to penetrate through holes 31 formed in the support plate 30, and a pulley 32 is attached to a tip end thereof. An endless belt 34 is wound around the pulley 32, and the belt 34 is stretched around a pulley 36 provided below the main shaft 26. The main shaft 26 is arranged in the vertical direction, and is rotatably provided on the apparatus main body 11 via bearings 38, 38. Therefore, according to the eccentric rotation mechanism 14, when the motor 24 is driven, the driving force is generated by the pulley 32 and the belt 3
4 and a pulley 36 to transmit the power to the main shaft 26. As a result, the main shaft 26 is rotated about its axis 27. A drive eccentric shaft 28 is connected to an upper portion of the main shaft 26. The drive eccentric shaft 28 is provided at a position where the shaft center 29 is eccentric with respect to the shaft center 27 of the main shaft 26, and a bearing 40 is provided on a cup-shaped bearing portion 15 formed at the lower center of the polishing table 12. Connected.
Therefore, when the main shaft 26 is rotated about the shaft 27, the drive eccentric shaft 28 is eccentrically rotated about the shaft 27 of the main shaft 26, and the polishing table 12 is moved about the shaft 27 of the main shaft 26. The orbit is driven. The rotation of the polishing table 12 (the rotation of the polishing table 12 about the axis 29 of the drive eccentric shaft 28) accompanying the revolving drive of the polishing table 12 is prevented by the rotation preventing device 16. The anti-rotation devices 16, 16 will be described later. In this embodiment, the connection structure in which the polishing table 12 is connected to the drive eccentric shaft 28 provided integrally with the main shaft 26 via the bearing 40 has been described, but the present invention is not limited to this. For example, the main shaft 26 is formed in a hollow shape,
The drive eccentric shaft 28 is inserted and arranged in the hollow portion, and is supported by the main shaft 26 so as to be eccentrically rotatable via a bearing. The connection structure in which the polishing table 12 is directly connected to the drive eccentric shaft 28 can also be applied. . The polishing section 18 has a polishing cloth 42 for polishing the face surface 21 of the CRT glass panel 20. This polishing cloth 42 is fixed to a base plate 44. The base plate 44 is provided with a piston 47 of a cylinder device 46 for vertically moving the base plate 44 and a swing arm 49 of a horizontal swing mechanism 48 for swinging the base plate 44 in the horizontal direction.
0. A slurry supply pipe 52 is connected to the base plate 44, and the slurry is supplied to the polishing pad 42 from the slurry supply pipe 52. Therefore, according to the polishing section 18, by expanding and contracting the piston 47 of the cylinder device 46,
The polishing cloth 42 can be moved forward and backward with respect to the face surface 21, and the polishing cloth 42 with respect to the face surface 21 can be moved.
Polishing pressure can be set. After the polishing pressure is set, the slurry is supplied from the slurry supply pipe 52 to the polishing cloth 42 while the swing arm 49 of the horizontal swing mechanism 48 is reciprocated right and left in FIG.
The entire area can be polished. As the horizontal swing mechanism 48, a cylinder device may be applied, or a mechanical drive device, for example, a drive device having a link mechanism may be applied. Further, in the present embodiment, the polishing cloth 42 is used as a polishing tool for the face surface 21, but the present invention is not limited to this.
Not only can the material be appropriately selected depending on whether rough polishing or finish polishing is performed, and various forms can be used. For example, a drum polishing method may be adopted in which a cylindrical drum polishing tool made of rubber or felt is used, and the drum polishing tool is pressed against the face surface 21 and polished while rotating the drum polishing tool about a central axis. In such a drum polishing method, a rotating hollow cylindrical drum polishing tool having flexibility is rotated while being pressed against a face surface 21 of a glass panel 20 for a cathode ray tube while a predetermined internal pressure is applied, and a predetermined hardness and particle size are determined. The slurry in the form of a slurry is supplied and polished in the meantime. Since this polishing method has good followability to the face surface 21, it is effective as a polishing method for the glass panel 20 for a CRT having various curvatures. Next, the anti-rotation device 16 will be described. As shown in FIG. 3, the anti-rotation device 16 is
0 and a driven eccentric shaft 62 and the like. The main shaft 60 is rotatably supported by hollow housing 64 via bearings 66 and 68, and the driven eccentric shaft 62 is connected to the upper end of the main shaft 60. Main shaft 60
The amount of eccentricity of the shaft 63 of the driven eccentric shaft 62 with respect to the shaft core 61 is set equal to the amount of eccentricity of the drive eccentric shaft 28 with respect to the main shaft 26 of the eccentric rotation mechanism 14 shown in FIG. As a result, the polishing table 12 is revolved in a well-balanced manner. A ring-shaped mounting plate 70 is rotatably provided on the driven eccentric shaft 62 via a bearing 72.
The mounting plate 70 is fixed to the polishing table 12 by screws 74. Next, the installation location of the anti-rotation device 16 will be described. As shown in FIG. 2, two anti-rotation devices 16 are installed at the left side in FIG. In addition, the anti-rotation device 16,
The 16 installation locations are the B position and the C position in FIG. Referring to FIG. 4, a revolving lock mechanism of the polishing table 12 and a countermeasure thereof will be described. First, the revolution lock mechanism will be described. When there is only the driven eccentric shaft A on the linear extension line L1 positioned by the two points of the shaft center 27 of the main shaft 26 of the eccentric rotation mechanism 14 and the shaft center 29 of the drive eccentric shaft 28, the polishing table 12 is revolved. Then, since the driven eccentric shaft A may rotate in the opposite direction, the polishing table 12 may be locked without revolving. Such a problem similarly occurs when the driven eccentric shaft B is installed on the opposite side of the driven eccentric shaft A with the eccentric rotation mechanism 14 interposed therebetween (in parallel with the driven eccentric shaft A). Therefore, as a measure for preventing such a problem, in the present embodiment, the position where the straight line connecting the two driven eccentric shafts B and C and the drive eccentric shaft 28 does not become a straight line is set.
Two driven eccentric shafts B and C were arranged. In principle, the driven eccentric shaft C may be installed at a position that does not overlap with the extension line L1, but at a position very close to the extension line L1, the polishing table 12 may be locked or adversely affect the operation of starting revolution. May be given. Therefore, from such a viewpoint, the drive eccentric axis C is provided at a position on the extension line L2 in a direction (90 °) orthogonal to the extension line L1. In practice, the driven eccentric shaft C may be installed at a position of 90 ° ± 45 °. Therefore, in the present embodiment, the two driven eccentric shafts 62, 62 are installed at the optimum positions for preventing the revolution lock of the polishing table 12, so that the revolution lock of the polishing table 12 is surely achieved. Can be prevented. Next, the operation of the polishing apparatus 10 configured as described above will be described. First, the glass panel 20 for a cathode ray tube is placed on the polishing table 12, and the positioning member 22,
22 and are positioned and fixed. And the polishing unit 18
Drive the cylinder device 46 to extend the piston 47,
The polishing cloth 42 is pressed against the face surface 21 and the polishing pressure is set to a predetermined pressure. Thus, the preparation for polishing is completed. Next, the motor 24 is driven and the horizontal swing mechanism 48 is driven, and a slurry is supplied to the polishing pad 42 to start polishing the face surface 21. The motor 2
When 4 is driven, its rotational force is transmitted to the main shaft 26 via the belt transmission mechanism, and the main shaft 26 rotates. When the main shaft 26 rotates, the drive eccentric shaft 28 provided at a position eccentric to the main shaft 26 rotates eccentrically about the axis 27 of the main shaft 26, whereby the polishing table 12 is driven to revolve. Here, the drive eccentric shaft 28 has a bearing 40
When the main shaft 26 rotates, the polishing table 12 rotates together with the rotation of the main shaft 26, that is, the polishing table 12 rotates about the axis 29 of the drive eccentric shaft 28. And But,
Since the polishing table 12 is fixed to the apparatus main body 11 via the rotation preventing devices 16, 16, the polishing table 12 smoothly revolves while its rotation is prevented. Therefore, according to the rotation preventing device 16 for the rotating plate, the face surface 21 can be uniformly polished. In this embodiment, since the two driven eccentric shafts 62 and 62 are disposed at positions where the straight line connecting the two driven eccentric shafts 62 and the drive eccentric shaft 28 is not straight, the polishing table The revolving lock of the polishing table 12 when the revolving wheel 12 starts revolving can be prevented.
In the present embodiment, the rotation preventing device for the polishing apparatus table 12 has been described, but the present invention is not limited to this. That is, any device can be applied as long as it is a device for preventing the rotation of the rotating plate that revolves around the driving eccentric shaft. As described above, according to the apparatus for preventing rotation of a rotating plate according to the present invention, two rotating eccentric shafts and a driving eccentric shaft are located at a position where the straight line connecting the two eccentric shafts is not straight. Since the driven eccentric shaft is disposed, the revolving lock of the rotating plate can be prevented.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view including a partial cross section of a polishing apparatus according to an embodiment. FIG. 2 is a top view of the polishing apparatus shown in FIG. 1. FIG. FIG. 4 is a sectional view of an applied driven eccentric shaft. FIG. 4 is an explanatory view for explaining an installation place of a driven eccentric shaft. [Description of References] 10 ... Polishing device 12 ... Polishing table 14 ... Eccentric rotation mechanism 16 ... Rotation prevention device 18 ... Polishing unit 20. CRT glass panel 24. Motor 28. Drive eccentric shaft 62.

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Yasuo Sato             1-10-1 Kitahoncho, Funabashi City, Chiba Prefecture Asahi Glass             Child Co., Ltd. F term (reference) 3C034 BB71                 3C049 AB01 AC04 CA01 CA06

Claims (1)

Claims 1. An apparatus for preventing rotation of a rotating plate provided to revolve around a drive eccentric shaft, wherein two driven eccentric shafts having an eccentric amount equal to the eccentric amount of the drive eccentric shaft. Is provided on the rotating plate to prevent rotation of the rotating plate, and the two driven eccentric shafts are installed at positions where a straight line connecting the two driven eccentric shafts and the drive eccentric shaft is not straight. An apparatus for preventing rotation of a rotating plate.