JP3804177B2 - Polishing method and apparatus for funnel glass for cathode ray tube - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method and an apparatus for polishing a sealing surface of a funnel glass for a cathode ray tube.
[0002]
[Prior art]
The sealing surface of the funnel glass for the cathode ray tube with the panel glass is required to be flat and free from scratches from the viewpoint of the sealing strength and the degree of sealing in the vacuum state of the cathode ray tube. The funnel glass and panel glass are sealed by aligning the alignment points of the funnel glass and panel glass so that the center line of the electron gun attached to the neck and the center of the panel glass are aligned. line of connecting the center and the neck center or yoke center indexed from the sidewall support points 3 points an alignment point (center axis), it is necessary interlinked straight sealing surface. This is because the center axis is strictly defined so as to be substantially orthogonal to the seal surface in the product standard of funnel glass in order to accurately obtain alignment with the panel glass.
[0003]
However, because funnel glass is made by molding molten glass and then welding the neck, the shape and positional relationship of the sealing surface cannot be satisfied. Normally, this sealing surface should be polished to meet the standards. I have to.
[0004]
As the polishing method conventionally, a method described in JP-B-61-19389, there is known a method described in JP-B-45-16368.
The former is a method of rotating while supporting the funnel glass on the outside of the neck and pressing it against one large disk-type polishing grindstone that rotates at high speed, and since the funnel glass cannot be fixed firmly with the position adjusted, the sealing surface Remains to be polished in parallel to the molding surface. Accordingly, the polished seal surface is not necessarily orthogonal to the central axis, and depends on the accuracy of the molding and neck welding processes.
[0005]
On the other hand, in the latter, the funnel glass is rotated while being fixed at the inner four corners close to the yoke portion inner surface and the seal surface, and is polished while being pressed against a plurality of concentric grinding wheels. There is no guarantee of the position with respect to the point and the center of the inner surface of the neck, and it depends on the accuracy of the molding and neck welding process as in the former.
[0006]
In both methods, after polishing the seal surface, it is possible to correct the position by polishing the three side wall support points with reference to the three points on the seal surface and the neck inner surface, but depending on the type of funnel glass, the side wall support points cannot be polished. Production costs increase as the number of processes increases.
Further, since the polishing by rotating the funnel glass itself, supporting and fixing the funnel glass tends less stable, and equipment also tends to become complicated.
[0007]
[Problems to be solved by the invention]
The present invention aims to eliminate the above-mentioned drawbacks of the prior art, and improves the positioning accuracy of the funnel glass by polishing the sealing surface in a state where the funnel glass is fixed without being rotated. be improved, molding and without being influenced by the accuracy of the neck of the welding process, determined by the center and the neck in the mind that are indexed by Neighboring Ru three support points in the vicinity of the sealing surface of the funnel glass side wall outer surface To polish the sealing surface of the funnel glass so as to be orthogonal to the central axis, and to be able to polish a predetermined sealing surface even for funnel glass in which the side wall support point cannot be finished and polished after polishing of the sealing surface. The problem is to solve the problem of increased production costs due to increased processes.
[0008]
[Means for Solving the Problems]
The present invention relates to a method for polishing a seal surface of a funnel glass for a cathode ray tube with a panel glass, a center determined by three adjacent support points in the vicinity of the seal surface on the outer surface of the funnel glass side wall, and three on the inner surface of the neck. The center axis of the funnel glass is centered as a straight line passing through the center indexed by the support point, and the funnel glass is positioned and fixed by holding the seal surface downward with respect to the center axis. and, in the fixed state without rotating the funnel glass, and characterized by polishing the sealing surface by the sealing surfaces to pivot the grindstone so as to be perpendicular to the central axis about the central axis of the funnel glass A method for polishing funnel glass for a cathode ray tube is provided.
[0009 ]
[0010]
Furthermore, the present invention is an apparatus for polishing a seal surface of a funnel glass for a cathode ray tube with a panel glass, and a yoke support and a funnel glass for supporting the funnel glass on the inner surface of the yoke portion so that the seal surface faces down. A device for centering and positioning the center axis of the funnel glass at the three support points on the funnel side wall and the three points on the inner surface of the neck. A fixing means for positioning, and a polishing grindstone provided below a sealing surface of the funnel glass and having a polishing surface orthogonal to the central axis of the funnel glass, and the polishing grindstone is swiveled around the central axis The cathode ray tube fan is configured to polish the sealing surface of the funnel glass in a fixed state without being rotated. To provide a polishing apparatus of Nerugarasu.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIGS. 1 and 2, the cathode-ray tube funnel glass 1 has a neck 4 sealed at one end and a generally funnel-shaped hollow having a substantially rectangular opening surrounded by a side wall at the other end. It is a glass body. The sealing surface 6 with the panel glass is formed by polishing this opening. This funnel glass 1 has three support points 3 in the vicinity of the sealing surface 6 on the outer surface of the adjacent side walls . Usually has two support points 3 on the long side of the sealing surface 6, it has one of the supporting points 3 on the short side.
[0012]
These support points 3 are specified as a part of the outer surface of the side wall or a part of the protrusion provided on the wall surface, and are formed at a predetermined distance from the reference axis determined by the design of the funnel glass. Neck 4, the tube axis Ru are sealed so as to coincide with the reference axis. As a result, the center axis extending through the center of the neck 4 or the center of the yoke portion 5 and the center of the opening indexed by the three support points theoretically coincides with this reference axis. However, errors occur in actual products due to molding accuracy and neck sealing accuracy.
[0013]
Further, these support points 3 are often used as reference points for inspecting the sealing accuracy of the neck 4 or as reference points for alignment when sealing the funnel glass and the panel glass when manufacturing the cathode ray tube. Is done . Polishing the sealing surface 6 relative to the hunt supporting point three, it means that share the supporting points 3 having such a role, a great advantage which can not be obtained by polishing so far.
[0014]
In the present invention, the sealing surface 6 is polished while the funnel glass is fixed without being rotated. As is conventional, in the case of polishing the sealing surface 6 while rotating the funnel glass, there is also limitation of the device as, provide support point of the funnel side wall with or or utilized as a reference in positioning It is practically difficult. On the other hand, since the present invention does not rotate the funnel glass, it can be positioned with reference to the support point of the funnel side wall.
[0015]
In the present invention, center axes passing through the centers of the neck side and the opening side of the funnel glass 1 are centered, the funnel glass is positioned based on the center axis, and the sealing surface is polished. Usually, the center of the neck side to center as the center of a good yoke portion or neck inner surface forming accuracy, since the sealing accuracy of the neck is ignored if the yoke portion center, centering by the center of the neck inner surface Is preferable. The center on the opening side is determined from the three support points 3 on the adjacent funnel side walls. Specifically, for example, the center is determined from three points on the neck inner surface 2 and three support points 3 in the vicinity of the seal surface of the funnel glass side wall, and the center axis is centered as a straight line passing through these centers.
[0016]
In the present invention, the funnel glass is positioned on the basis of the central axis, and is supported and fixed so as not to move in that state, so that the central axis is always orthogonal to the polishing surface of the grinding stone, and then the sealing surface 6 The polished seal surface 6 is always made perpendicular to the central axis.
[0017]
For example, when the neck 4 is inclined and welded to the funnel glass 1 as shown in FIG. 3, the central axis 19 passing through the center of the neck inner surface and the center calculated from the three support points 3 on the funnel side wall is The surface that is inclined with respect to the case where the neck is not inclined and is perpendicular to the central axis is 20. Therefore, in the present invention, the sealing surface is polished so as to match the surface 20 with a polishing grindstone having a polishing surface orthogonal to the central axis 19.
[0018]
In the present invention, as described above, the funnel glass is fixed without being rotated, and the polishing grindstone is moved in the direction orthogonal to the central axis of the funnel glass for polishing. In this case, a single grinding wheel may be used, but 2 to 4 are usually used in combination in order to balance the polishing efficiency or the polishing pressure. These polishing grindstones are arranged at equal intervals below the funnel glass positioned and fixed, and turn around the funnel glass, more preferably around the central axis of the funnel glass to polish the sealing surface. At this time, the polishing grindstone may be swung in a direction different from the turning direction.
[0019]
【Example】
Next, embodiments of the present invention will be described with reference to the drawings. 4 is a schematic side view of a main part of the polishing apparatus according to the embodiment of the present invention, and FIG. 5 is a side view of the polishing apparatus according to the embodiment of the present invention.
When the funnel glass 1 is supplied to the apparatus, the funnel glass is mounted on the yoke support 9 attached to the main shaft 10, and the inside of the yoke portion 5 is supported by the yoke support 9. I support you. In this case, the yoke support 9 is attached to the main shaft 10 elastically, for example, and when an external force is applied to the funnel glass, the yoke support 9 fluctuates up and down and left and right to obtain a desired degree of freedom. .
[0020]
A bar-shaped support 11 is connected to the upper portion of the main shaft 10. When the funnel glass is placed on the yoke support 9, the bar-shaped support 11 is inserted into the neck 4. Since three centering tools 12 are provided at the top of the rod-shaped support 11 so as to be pushed out at equal intervals of 120 degrees in the horizontal direction, they are mounted on the yoke support 9 at the same time as they are inserted into the neck. Index the center of the neck of the funnel glass. The height of the centering tool 12 is not particularly limited, but it is usually preferable that the centering tool 12 is adjusted to the position defined by the quality standard for the sealing accuracy of the neck 4.
[0021]
On the other hand, three positioning tools 14 are installed at predetermined positions from the main shaft 10 corresponding to the support points 3 on the side walls adjacent to the funnel glass. These positioning tools together with the above-described neck centering tool 12 function as a funnel glass positioning device. In this example, the positioning tool 14 is provided so that the pushing position can be made constant by the cylinder 13, but these may be fixed at a fixed position.
[0022]
Further, three pressing tools 15 are provided so as to face the positioning tools 14. These pushers 15 are attached to the cylinder 16 and act so as to press the funnel glass 1 against the positioning tool 14 by the operation of the cylinder 16. Further, a fixing means 18 is provided above the funnel glass 1 supported by the yoke support 9 and attached to a head 17 that can be moved in the vertical direction by a cylinder 32. The fixing means 18 is in contact with the outer surface of the yoke portion of the funnel glass 1 from above, and holds the funnel glass at a constant height so that the funnel glass does not move further upward even when a force from below is applied to the funnel glass. .
[0023]
The funnel glass 1 mounted on the yoke support 9 is in a state of being able to move around the centering point of the neck, and in this state, three support points 3 near the seal surface of the adjacent funnel glass side wall are attached to the cylinder 13. The positioning tool 14 is pushed in and the other adjacent funnel side wall is pressed toward the positioning tool 14 with the pressing tool 15 attached to the cylinder 16 from the opposite side. The funnel glass 1 is positioned by the positioning tool 14 and the pressing tool 15, and at the same time, is fixed in a state where it does not rotate around the left and right and the main shaft 10. Next, the head 17 is lowered, and the fixing means 18 attached to the head is pressed against the outer surface of the yoke portion so that the funnel glass does not move upward during polishing.
[0024]
Next, four polishing wheels 8 are arranged on the spindle table 21 at equal intervals on a concentric circle, and the polishing wheel 8 and the drive motor 22 are connected by a rotating shaft 23. The rotating shaft 23 is accommodated in a bearing 24 and can be moved up and down with respect to the spindle table 21 together with the bearing. The bearing 24 is moved up and down by a circular rail 26 that moves up and down by a cylinder 25 connected to the main shaft 10. When the bearing 24 is pushed up, the grinding stone 8 hits the sealing surface of the funnel glass 1 to be polished. The polishing surface of the polishing grindstone 8 is formed so as to be orthogonal to the central axis 10 or the central axis of the funnel glass 1, and the push-up amount or polishing amount of the polishing grindstone 8 is constant from the surface where the seal surface includes the funnel side wall. It is controlled to be a distance.
[0025]
The spindle table 21 can be rotated with respect to the spindle 10, and rotates around the spindle 10 when the gear 27 on the outer periphery of the table is rotated by the drive motor 28. Since the grinding wheel 8 is installed on the spindle table 21, when the table 21 rotates, the grinding wheel 8 turns around the spindle 10 parallel to the rotation axis of the grinding wheel. In addition, when the spindle table is rotating, the electric power supplied to the grinding wheel drive motor 22 is such that the contact 30 attached to the tip of the guide rod 29 descending from the spindle table is applied to the conduction band 31 below the spindle. It is done by touching.
[0026]
【The invention's effect】
According to the method of the present invention, since the sealing surface is polished in a state where the funnel glass is fixed without being rotated, it is possible to perform positioning and support fixing of the funnel glass from the outside of the funnel side wall. The center axis can be centered and positioned. As a result, the sealing surface can be polished so as to be orthogonal to the central axis, so that more ideal polishing can be realized and the polishing accuracy can be improved. Furthermore, a flat seal surface orthogonal to the central axis can be obtained even for funnel glass whose support points on the funnel side walls cannot be polished after polishing the seal surface.
[0027]
Further, since the sealing surface is positioned polished with respect to the center to be indexed from the three supporting region point near the sealing surface of the funnel glass side walls, as compared with a method of polishing by following the sealing surface on the molding surface, the seal surface portion There is also an advantage that shape management at the time of molding is relaxed.
Furthermore, by not rotating the funnel glass, a device for positioning and fixing the funnel glass in the polishing apparatus can be simplified.
[Brief description of the drawings]
FIG. 1 is a plan view of a funnel glass. FIG. 2 is a side view of the funnel glass. FIG. 3 is a side view of a main part of an apparatus for carrying out the polishing method of the present invention. FIG. 5 is a side view of a polishing apparatus according to an embodiment of the present invention.
1: Funnel glass 2: Neck inner surface 3: Support point 4: Neck 5: Yoke part 6: Sealing surface 8: Polishing grindstone 9: Yoke support tool 10: Spindle 11: Bar-shaped support tool 12: Centering tool 14: Positioning tool 18: Fixing means 19: central axis 21: spindle table

Claims (2)

In the method of polishing the sealing surface with the panel glass of the funnel glass for cathode ray tube,
The center axis of the funnel glass is defined as a straight line passing through the center determined by three adjacent support points near the seal surface on the outer surface of the funnel glass side wall and the center determined by the three support points on the inner surface of the neck. Centered,
Using the central axis as a reference, the funnel glass is positioned and fixed by holding the seal surface downward.
A cathode ray, wherein the sealing surface is polished by rotating a polishing grindstone around the central axis of the funnel glass so that the sealing surface is orthogonal to the central axis in a state where the funnel glass is fixed without rotating. A method for polishing funnel glass for tubes. A device for polishing a sealing surface of a funnel glass for a cathode ray tube with a panel glass, a yoke support for supporting the funnel glass on the inner surface of the yoke portion so that the sealing surface is down, and the funnel glass on the outer surface of the funnel glass side wall. A device that centers and positions the center axis of the funnel glass at the three support points near the seal surface and the three points on the inner surface of the neck, and contacts the outer surface of the yoke portion of the positioned funnel glass so that the funnel glass does not move upward. A fixing means for localizing, and a polishing grindstone provided below the sealing surface of the funnel glass and having a polishing surface orthogonal to the central axis of the funnel glass,
An apparatus for polishing a funnel glass for a cathode ray tube configured to polish the sealing surface of the funnel glass in a state where the polishing grindstone is swiveled around a central axis and fixed without rotating.

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