JP2003217446A - Method of manufacturing color cathode ray tube - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a color cathode ray tube, making it possible to produce positive tensile force as preset after fixing a color selecting electrode to frames and to prevent the occurrence of wrinkling. <P>SOLUTION: The method comprises a mounting step of applying compressive force to the direction of reducing a space between the frames 11 to join the color selecting electrode 16 to the frames 11 while applying tensile force to the color selecting electrode 16. The curvature radius of the end face of a pressure plate 15 on the side of the color selecting electrode 16, to which the compressive force is applied, is almost the same as the curvature radii of the upper faces of the frames 11 after the compressive force is applied thereto. Thus, pressure can be applied to the upper ends of the frames 11 all over the total length of the pressure plate 15 and restoring force having almost the same magnitude as the pressure applied thereto can be produced after the compressive fore is released, making it possible to produce the positive tensile force as preset after fixing the color selecting electrode 16 to the frames 11. <P>COPYRIGHT: (C)2003,JPO

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 color cathode ray tube used for a television receiver, a computer display and the like.

[0002]

2. Description of the Related Art In recent years, in a color cathode ray tube, flattening of a panel has been promoted because it has the advantages that the range of reflected external light can be reduced and image distortion can be prevented. The color cathode ray tube plays a role of color selection for three electron beams emitted from an electron gun, and a plate-shaped color selection electrode (shadow mask) having a plurality of apertures is fixed to a frame to perform color selection. The electrode structure is formed.

During operation of the cathode ray tube, thermal expansion due to electron beam bombardment displaces the apertures of the color selection electrode, and the electron beam passing through the apertures does not hit the prescribed phosphor correctly, resulting in uneven color. A doming phenomenon occurs. For this reason, a tensile force capable of absorbing thermal expansion due to a temperature rise of the color selection electrode is applied in advance to stretch and hold the color selection electrode on the support.

In the tensioning step of retaining the tension, a tensile force is applied to the color selection electrode and a compression force is applied to the frame, and then the color selection electrode is joined to the upper surface of the frame by welding. After welding, it is important that a predetermined tensile force is applied to the color selection electrode and that there is no deformation due to wrinkling.

Japanese Unexamined Patent Publication No. 2000-67747 proposes a manufacturing method in which a compressive force is applied to a frame by pressing an upper end portion of a side surface of the frame. According to such a manufacturing method, if the upper end of the frame can be surely pressed, the frame having substantially the same size as the applied frame pressurizing force is compared with the case where the same amount of compressive force is applied to the lower end. The restoring force of the frame 10 can be obtained, and the tensile force after fixing the color selection electrode to the frame can be reliably obtained as set.

Further, Japanese Unexamined Patent Publication No. 2000-315454 proposes a manufacturing method in which a curved surface of a support is brought into contact with the back surface of the color selection electrode in the stretching step to prevent the color selection electrode from wrinkling. ing.

[0007]

However, the conventional manufacturing method as described above has the following problems. In the manufacturing method in which the upper end of the frame is pressed in the straddling step, reliable pressurization of the upper end of the frame is a prerequisite for ensuring a sufficient frame restoring force. However, in the initial setting before pressurization, the pressure plate is
Even if it is in contact with the upper end of the frame, the frame is displaced upward with respect to the pressure plate along with the application of compressive force, and the radius of curvature of the upper surface of the frame also changes. There is a problem that the lower side is pressurized compared to the above, and it may not be possible to secure a sufficient frame restoring force.

Further, in order to prevent the generation of wrinkles, in the manufacturing method in which the curved surface of the support is brought into contact with the back surface of the color selection electrode,
In the initial setting, even if the radius of curvature of the curved surface of the support and the radius of curvature of the upper surface of the frame match, the curvature of the upper surface of the frame becomes smaller due to the pressure applied to the frame, and these radii of curvature differ.

Therefore, even if the color selection electrode is in contact with the upper surface of the frame, it is not completely in contact with the curved surface of the support, and the color selection electrode is deformed so as to hang down. The degree of this deformation is different in each part of the color selection electrode, and the length of the color selection electrode in the stretching direction is different if the position of the support in the curved surface direction is different.

When a tensile force is applied to the color selection electrode in this state, the color selection electrode is distorted due to the dimensional difference between them.
When the distortion is large, wrinkles occur on the color selection electrode.
Even if the wrinkle disappears when the tensile force is applied to the color selection electrode, the thermal expansion amount of the color selection electrode during the high temperature heat treatment in the subsequent process and by the electron beam impinging on the color selection electrode When it becomes larger than the thermal expansion of the frame,
This may cause wrinkles.

Further, in detail, when the color selection electrode hangs down, a small gap is generated between the upper surface of the frame and the color selection electrode. In this case, stress is applied to the color selection electrode so as to eliminate the gap during welding, and the color selection electrode is distorted, causing wrinkles.

The present invention is to solve the above-mentioned conventional problems, and it is possible to reliably obtain the tensile force after fixing the color selection electrode on the frame as set and to prevent the occurrence of wrinkles. It is an object of the present invention to provide a method of manufacturing a color cathode ray tube that can achieve the above.

[0013]

In order to achieve the above object, a first method of manufacturing a color cathode ray tube according to the present invention is to apply a compressive force in a direction in which a space between opposing sides of a frame is reduced, and An end face on the color selection electrode side of a pressure plate for applying the compression force, which comprises a stretching step of joining the color selection electrode to the frame in a state where a tensile force is applied to the selection electrode in a direction opposite to the compression force. And the radius of curvature of the joint surface of the color selection electrode of the frame after applying the compressive force are substantially the same. According to the manufacturing method of the color cathode ray tube as described above, since the radius of curvature of the upper end of the pressure plate is substantially the same as the radius of curvature of the upper surface of the frame after the compression force is applied, the total length of the pressure plate after the compression force is applied. It becomes possible to pressurize the upper end portion of the frame over, and it is possible to effectively apply a compressive force to the frame,
After releasing the compressive force, the restoring force of the frame having substantially the same magnitude as the applied pressure of the frame can be obtained, and the tensile force after fixing the color selection electrode to the frame can be reliably obtained as set.

Next, in the second method of manufacturing a color cathode ray tube according to the present invention, a compressive force is applied in a direction in which the distance between the opposing sides of the frame is reduced, and the color selection electrode is pulled in a direction opposite to the compressive force. A step of joining the color selection electrode to the frame in a state where force is applied, and in the step of stretching,
Of the two surfaces of the color selection electrode, a support that supports the color selection electrode by contacting the surface on the frame side is used, and the color of the frame when the color selection electrode is placed on the support. The radius of curvature of the bonding surface of the selection electrode and the radius of curvature of the contact surface of the support on the color selection electrode are substantially the same. According to the manufacturing method of the color cathode ray tube as described above, it is possible to prevent the generation of a gap between the color selection electrode and the upper surface of the frame when the color selection electrode is placed on the support. Therefore, the length of the color selection electrode in the stretching direction is uniform in the curved surface direction of the support over the entire color selection electrode, and the distortion of the color selection electrode due to the application of tensile force can be prevented and the occurrence of wrinkles can be prevented. .

Next, in the third method of manufacturing a color cathode ray tube according to the present invention, a compressive force is applied in a direction in which the distance between the opposite sides of the frame is reduced, and the color selection electrodes are pulled in a direction opposite to the compressive force. A step of joining the color selection electrode to the frame in a state where a force is applied, and a holding means for sandwiching both sides of the color selection electrode is used to apply the tensile force, and the color selection electrode is applied to the frame. And the holding means sandwiches both sides of the color selection electrode, the radius of curvature of the joint surface of the color selection electrode of the frame, and the holding means of at least the color selection electrode It is characterized in that the radius of curvature of the surface that comes into contact with the surface on the frame side is substantially the same. According to the method of manufacturing a color cathode ray tube as described above, it is possible to prevent the generation of a gap between the color selection electrode and the upper surface of the frame, prevent the color selection electrode from being distorted due to the application of tensile force, and prevent the occurrence of wrinkles.

Next, in the fourth method of manufacturing a color cathode ray tube according to the present invention, a compressive force is applied in the direction in which the distance between the opposing sides of the frame is reduced, and the color selection electrodes are pulled in the direction opposite to the compressive force. A step of joining the color selection electrode to the frame in a state in which a force is applied, the radius of curvature of the end surface of the pressure plate to which the compression force is applied on the side of the color selection electrode, and after applying the compression force. And the radius of curvature of the joint surface of the color selection electrode of the frame is substantially the same, and in the stretching step, the color selection is performed by contacting the surface of the color selection electrode on the frame side. Using a support that supports the electrode,
The radius of curvature of the joint surface of the color selection electrode of the frame when the color selection electrode is placed on the support is substantially the same as the radius of curvature of the contact surface of the color selection electrode of the support. Yes, a state in which holding means for sandwiching both sides of the color selection electrode is used for applying the tensile force, the color selection electrode is placed on the support, and the holding means sandwiches both sides of the color selection electrode. The radius of curvature of the joint surface of the color selection electrode of the frame and the radius of curvature of at least the surface of the holding means that abuts the surface of the color selection electrode on the frame side are substantially the same. To do.

According to the manufacturing method of the color cathode ray tube as described above, the tensile force after fixing the color selection electrode to the frame can be reliably obtained according to the setting, and the distortion of the color selection electrode due to the application of the tensile force can be prevented. It can prevent wrinkles.

[0018]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a sectional view of a color cathode ray tube according to an embodiment of the present invention. The color cathode-ray tube 1 shown in this figure has a substantially rectangular face panel 2 having a phosphor screen surface 2a formed on the inner surface thereof, and a funnel 3 connected to the rear of the face panel 2 to form an envelope. Has been formed. An electron gun 4 that emits three electron beams is built in the neck portion 3 a of the funnel 3, and the electron beam emitted from the electron gun 4 is generated by a deflection yoke 5 arranged on the outer peripheral surface of the funnel 3. , Is deflected and reaches the screen surface 2a.

Inside the face panel 2, a color selection electrode (shadow mask) 6 provided so as to face the phosphor screen surface 2a is arranged. The color selection electrode 6 plays a role of color selection for the three electron beams emitted from the electron gun 4. A indicates the electron beam trajectory. The color selection electrode structure in which the color selection electrode 6 is joined to the frame 7 is hooked on the panel pin 9 of the face panel 2 by the spring 8 provided in the frame 7.

FIG. 2 is a perspective view of an example of the color selection electrode assembly according to this embodiment. Frame-shaped frame 10 (Fig. 1
(Corresponding to the frame 7 of FIG. 2), a color selection electrode 16 having a large number of openings 17 formed in a plate member is joined. During operation of the cathode ray tube, the opening 17 of the color selection electrode 16 is displaced due to thermal expansion due to the bombardment of the electron beam.
The electron beam that passes through does not hit the predetermined phosphor correctly, causing a doming phenomenon in which color unevenness occurs.

For this reason, a tensile force capable of absorbing the thermal expansion of the color selection electrode 16 due to the temperature rise is applied in advance so that the color selection electrode 16 is stretched and held on the frame-shaped frame 10. According to the stretching and holding, the color selection electrode 1
Even if the temperature of 6 rises, it is possible to reduce the misalignment between the openings 17 of the color selection electrodes 16 and the phosphor stripes on the phosphor screen surface.

In the example of this figure, a tensile force is applied to the color selection electrode 16 in the direction of arrow A, and an arrow B is applied to the frame-shaped frame 10.
The color selection electrode 16 is joined to the upper surface of the long-side frame 11 by welding with a compressive force applied in the direction.

The steps until the color selection electrode structure shown in FIG. 2 is completed will be described below in the order of manufacturing steps. FIG. 3A shows a perspective view of the frame-shaped frame formed in the frame assembly process. The frame-shaped frame 10 includes a pair of long side frames 11
Is formed by welding the upper surfaces of the pair of short side frames 12 to the lower surfaces of the.

The long side frame 11 has a plate thickness of 1.4 to 1.8.
It is a press-punched material having a size of about mm that is bent. Further, in order to increase rigidity and ensure a predetermined strength, there is a bent portion 11a having a triangular cross section. Further, the end portion 11b of the bent portion is welded along the longitudinal direction. Like the long-side frame 11, the short-side frame 12 is made by bending a press-punched material having a plate thickness of 1.4 to 1.8 mm.

After the frame-shaped frame 10 is completed, the frame-shaped frame 10 is heat-treated under the conditions of, for example, 550 ° C. or higher for 15 minutes in order to remove the processing strain during welding in the frame heat treatment step.

Through the frame assembling process and the heat treatment process, the frame upper surface 11c, which is the bonding surface of the color selecting electrode 16, is distorted and the radius of curvature is also changed.
Therefore, in the next milling step, the frame upper surface 11c is cut to have a predetermined radius of curvature.
The purpose of this milling process is to correct the variation of the radius of curvature of the frame upper surface 11c due to the strain, remove the oxide film attached to the frame upper surface 11c in the heat treatment process, and smooth the surface condition of the frame upper surface 11c. There is.

Further, the radius of curvature of the frame upper surface 11c after cutting allows for a variation in the radius of curvature of the frame upper surface 11c which occurs when a compressive force is applied to the frame-shaped frame 10 in the subsequent stretching step. I am trying. By the cutting process of this process, the color selection electrode surface and the phosphor screen surface 2a
It is possible to set a proper distance to (FIG. 1) and prevent color shift due to position shift of the electron beam.

After these steps, the process moves to the stretching step. FIG.3 (b) has shown the perspective view in the stretching process. In the stretching step, the color selection electrode 16 has an arrow A
A tensile force is applied in the direction, and a compressive force is applied to the frame 10 in the arrow B direction.

FIG. 4 shows a frame-shaped frame 1 in the erection process.
0 is a side view (a view from arrow C in FIG. 3B), and FIG. 5 is a perspective view of a main part in the state of FIG. 4. The tensile force of the color selection electrode 16 in the direction of arrow A is
It is applied by a chucking device 13, which is a holding means that holds both ends of 6 from above and below. The chucking device 13 has an upper portion 13a and a lower portion 13b, the lower surface of the upper portion 13a has a concave curved surface shape, and the upper surface of the lower portion 13b has a convex curved surface. The shape is formed. Therefore, the color selection electrode 16 is held in a curved shape, and at least in the portion held by the chucking device 13,
The color selection electrode 16 is held in the same curved surface shape as the chucking device 13.

A pressure plate 15 is in contact with the longitudinal side surface of the long side frame 11. The pressure plate 15 is provided in the pressure unit 14 of the pressure device, and the pressure plate 15 presses the side surface of the long side frame 11 by moving the pressure unit 14 by a power unit (not shown). be able to. By the pressure applied by the pressure plate 15, the frame-shaped frame 1
A compressive force is applied to 0 in the direction of arrow B.

Further, a support 18 is arranged on the back surface of the color selection electrode 16 (on the side of the frame 10). Figure 5
As shown in, the support 18 is arranged over the entire length of the color selection electrode 16 in the long side direction (direction of arrow D), and the upper surface of the support 18 has a convex curved surface shape. Therefore, by bringing the color selection electrode 16 into contact with the upper surface of the support 18, the color selection electrode 16 can be held in a curved shape along the shape of the upper surface of the support 18.

In the stretching step, after the frame-shaped frame 10 is positioned, the frame-shaped frame 1 is applied with a pressure that does not move the frame-shaped frame 10 by the pressure plate 15.
0 is supported (hereinafter referred to as “temporary pressurization”). In this state, as shown in FIG. 3B, the color selection electrode 16 is placed on the frame-shaped frame 10, a predetermined tensile force is applied to the color selection electrode 16, and then a predetermined pressure is applied to the frame-shaped frame 10. Applied (hereinafter,
It is called "main pressurization". ) Do. It should be noted that the pressure in the temporary pressurization is a value that is sufficiently smaller than the pressure in the main pressurization, since a minimum pressure that does not move the frame 10 is sufficient.

The long-side frame 11 is provided for each temporary pressure and main pressure.
Deforms, and the radius of curvature of the frame upper surface 11c also changes.
Therefore, the radius of curvature of the upper surface 11c of the frame is different in each state of before pressurization, temporary pressurization, and main pressurization. For example, the radius of curvature of the frame upper surface 11a is
15,000 after cutting in the milling process
mm, 12500 mm after temporary pressurization, and 6000 mm after main pressurization. Hereinafter, this numerical example will be used in the case of a numerical example.

FIG. 6 shows the color selection electrode 16 after provisional pressurization.
5 shows the supporting state of No. 5, and each drawing corresponds to a cross-sectional view taken along line I-I of FIG. FIG. 6A is a diagram for comparison with the configuration of FIG. 6B, and shows the relationship between the frame-shaped frame 10, the color selection electrodes 16 (16 a, 16 b), and the support 21 after the temporary pressurization. Shows. In the configuration of FIG. 6A, the radius of curvature of the curved surface shape of the upper surface of the support 21 and the lower side portion of the chucking device (corresponding to the lower side portion 13b of FIG. 4) is set after the milling step (before pressing). The figure when it matches with the curvature radius of the frame upper surface 11c in FIG. Note that FIG. 6A is a comparative diagram used for explaining the problems of the conventional configuration in order to facilitate understanding of the function and effect in the embodiment of the present invention. Not shown.

Using the above numerical example, the radius of curvature R1 of the curved surface shape of the support 21 and the lower side of the chucking device.
Is 15,000 mm. Further, the radius of curvature R2 of the frame upper surface 11c after the temporary pressure is 12500 mm.

Assuming that the color selection electrode 16 is placed on the frame-shaped frame 10 before the frame-shaped frame 10 is temporarily pressed, the support body 21 and the radius of curvature R1 of the lower side of the chucking device, Since the curvature radius R2 of the frame upper surface 11c is the same, the back surface of the color selection electrode 16 is
The lower surface of the chucking device and the entire curved surface of the frame upper surface 11c are in contact with each other.

However, after the frame-shaped frame 10 is temporarily pressed, the radius of curvature R2 of the frame upper surface 11c becomes smaller, and the relationship of R2 <R1 is satisfied. Applying compressive force
The bottom surface of the long-side frame 11 is supported to perform this. For this reason,
As shown in FIG. 4, by applying a compressive force, the frame upper surface 11c is displaced in an arc shape as shown by a line 19 around the fulcrum a, and the frame upper surface 11c is pressed by the pressing plate 15.
It will be displaced upward with respect to. Long side frame 11
Since the corner portion 11d has a circular arc shape formed by bending, in order to perform stable support, the support position of the bottom surface is usually at a position substantially displaced to the center of the bottom surface or the tip 11e side. . In any case, the frame upper surface 11c is displaced upward with respect to the pressure plate 15.

Therefore, when a compressive force is applied to the frame-shaped frame 10, the central portion of the frame-shaped frame 10 is pushed up,
As the radius of curvature of the frame upper surface 11c becomes smaller,
The top portion (center portion) of the frame upper surface 11c projects above the support body 21.

Therefore, after the frame-shaped frame 10 is temporarily pressed, the color selection electrode 16 is attached to the frame upper surface 11c and the support 21.
If it is placed so that it touches both sides of the
The state becomes as shown in (a). That is, the color selection electrode 16
The position of is different between the portion of the frame upper surface 11c (the portion indicated by the reference numeral 16b) and the portion of the support 21 (the portion indicated by the reference numeral 16a).

However, in reality, the color selection electrode 16 which is a thin metal plate has a predetermined rigidity, and the reference numeral 16
As shown by a and 16b, the color selection electrode 16 is
It is impossible for the support 21 and the frame upper surface 11c to be in complete contact with each other.

In practice, the support 21 and the color selection electrode 16a
There will always be a gap between the frame upper surface 11c and the color selection electrode 16b. If welding is performed in this state, stress is applied to the color selection electrode 16 so as to eliminate these gaps, and the color selection electrode 16 is distorted. This causes wrinkles in the color selection electrode 16.

As shown in FIG. 6A, a step is formed between the frame upper surface 11c and the curved surface of the support 21. This step, that is, the drop of the curved surface of the support 21 with respect to the frame upper surface 11c is large at the central portion in the longitudinal direction of the long side frame 11 and hardly occurs at both end portions, as shown in the figure. When the color selection electrode 16 is placed in this state, the frame upper surface 11c supports the color selection electrode 16, but because of the step as described above, the color selection electrode 16 is provided between the pair of frame upper surfaces 11c. Drooping occurs.

Looking at this sag in the vertical direction (stretching direction), the sag amount increases as the distance from the frame upper surface 11c increases (as it approaches the central portion in the longitudinal direction). On the other hand, in the lateral direction (curved surface direction of the support body 21), as described above, the step is large in the central portion in the longitudinal direction of the long side frame 11, and therefore the amount of sag increases as it approaches the central portion in the lateral direction. Become. That is, the degree of vertical sag of the color selection electrode 16 varies depending on the position of the color selection electrode 16 in the horizontal direction.

Therefore, in this state, as shown in FIG. 4, when both ends of the color selection electrode 16 are held by the chucking device 13, even if the distance between the chucking devices 13 at both ends is fixed, Color selection electrode 16 held by
The length in the vertical direction will vary depending on the position of the color selection electrode 16 in the horizontal direction.

When a tensile force is applied to the color selection electrode 16 in this state, the color selection electrode 16 is distorted due to the respective dimensional differences, and when the distortion is large, the color selection electrode 16 is wrinkled. Even if the wrinkles disappear when the tensile force is applied to the color selection electrode 16, the high-temperature heat treatment in the subsequent process and the electron beam impinging on the color selection electrode 16 cause the color selection electrode 16 to fall. When the amount of thermal expansion of is larger than the amount of thermal expansion of the frame, it causes wrinkles.

On the other hand, FIG. 6B shows the upper surface of the support 18,
7A and 7B are diagrams showing a case where the radius of curvature of the curved surface shape of the lower side portion 13a of the chucking device 13 is matched with the radius of curvature of the frame upper surface 11c after the temporary pressure. Using the above numerical example, since the radius of curvature R2 of the frame upper surface 11c after provisional pressing is 12500 mm, the radius of curvature R1 of the curved surface shape of the support 18 and the lower side portion 13b of the chucking device 13 is 12500 mm. Become. The radius of curvature of the upper portion 13a of the chucking device 13 is preferably a radius of curvature that allows for the thickness of the color selection electrode 16 so that the color selection electrode 16 can be sandwiched in close contact.

The color selection electrode 16 is placed on the support 18, and the chucking device 13 as a holding means is used for the color selection electrode 1.
6 has a relationship of R2 = R1 in a state where both sides are sandwiched, as shown in FIG. 6B, after provisional pressurization, a gap is formed between the color selection electrode 16 and the frame upper surface 11c. The color selection electrode 16 is in contact with the upper surface 11c of the frame over the entire length of the long side frame 11 without being generated.

Therefore, the color selection electrode 16 as described above is used.
In this state, the length of the color selection electrode 16 held between the chucking devices 13 in the vertical direction is uniform over the entire color selection electrode 16 in the curved direction of the support 18. Therefore, even if a tensile force is applied, the color selection electrode 16 is not distorted, and it is possible to prevent the generation of wrinkles after welding or during high temperature heat treatment.

Next, application of compressive force to the frame 10 will be described. It is preferable to pressurize the long side frame 11 on the upper end portion (on the frame upper surface 11c side) of the longitudinal side surfaces of the long side frame 11. As a result, as compared with the case where a compressive force of the same magnitude is applied to the lower end side, after the compressive force after welding is released, a restoring force of the frame-shaped frame 10 having substantially the same magnitude as the applied pressure can be obtained. Therefore, the tensile force after fixing the color selection electrode 16 to the frame-shaped frame 10 can be reliably obtained as set.

FIG. 7 shows the long side frame 1 in the erection process.
It is a side view which shows the relationship between 1 and the pressure plates 15 and 22.
The pressure plates 15 and 22 indicate portions corresponding to pressure surfaces. FIG. 7A is a diagram for comparison with the configuration of FIG. 7B, in which the radius of curvature R3 of the upper end 22a of the pressure plate is set to the radius of curvature R4 of the frame upper surface 11c after the milling process (before pressure). It is a side view at the time of combining. Note that FIG.
FIG. 4A is a comparative diagram used to explain problems of the conventional configuration in order to facilitate understanding of the operation and effect in the embodiment of the present invention, and is not a diagram showing the embodiment of the present invention.

The long side frame 11 shown by the solid line shows the state before the pressurization, and the broken line shows the state after the main pressurization. In the above numerical example, the radius of curvature R4 of the frame upper surface 11c is 15000 mm, and in this case, the pressure plate upper end 22
The radius of curvature R3 of a is 15000 mm, which is the same as this.

As described above, the radius of curvature of the frame upper surface 11c after the temporary pressurization is different from that after the main pressurization. In the state before pressurization, the pressurizing surface of the pressurizing plate 22 is in contact with the upper end portion of the long side frame 11, but after the main pressurization, as shown by the broken line, the long side frame 11 is in the upper side. It is displaced upward with respect to the pressure plate 22 while curving so as to be convex to
The pressing plate 22 presses the lower end side of the long side frame 11 as compared with the state before pressing.

That is, at the beginning of main pressurization, the pressurizing plate 22 presses the upper end of the long side frame 11,
After the main pressurization, the pressurizing position is displaced to the lower end side, so that a sufficient restoring force of the frame-shaped frame 10 cannot be obtained eventually.

FIG. 7B is a side view showing the relationship between the long side frame 11 and the pressure plate 15 before pressure is applied according to this embodiment. In the configuration of this figure, the radius of curvature R3 of the upper end portion 15a of the pressing plate is set to the frame upper surface 11a after the main pressing.
It matches the radius of curvature of. Using the numerical example above,
The radius of curvature of the frame upper surface 11c after the main pressurization is 60
Since it is 00 mm, the radius of curvature R3 of the upper end 15a of the pressure plate is R3.
Is also 6000 mm. Further, since the drawing is before pressurization, the radius of curvature R4 of the frame upper surface 11c is 15000.
mm. Since there is a relationship of R3 <R4, the pressure plate 15 is arranged as close to the upper end side of the long side frame 11 as shown in the figure. In the example of this figure, in the central portion, the frame upper surface 11c and the upper end 15a of the pressure plate are substantially aligned.

FIG. 7C is a side view showing the relationship between the long side frame 11 and the pressure plate 15 after the temporary pressure is applied.
When the long side frame 11 is pressed, it is curved so as to be convex upward, and the radius of curvature R5 of the frame upper surface 11c is increased.
Is smaller than the radius of curvature R4 in FIG. 7 (b). Using the above numerical examples, the frame upper surface 11c after the temporary pressure is applied.
Radius of curvature R5 is 12,500 mm, R4 = 150
It is smaller than 00 mm.

Due to this bending, the long side frame 11 is displaced upward with respect to the pressure plate 15. As described above, before the temporary pressure is applied, the frame upper surface 11c and the pressure plate upper end 15a are set to substantially coincide with each other in the central portion.
In the state shown in the figure, the frame upper surface 11c is located at the center.
And the upper end 15a of the pressure plate are close to each other.

It is important that the upper end 15a of the pressure plate does not come into contact with the color selection electrode 16 in the temporary pressure state, and the upper end 15a of the pressure plate is located below the frame upper surface 11c. is necessary.

After the temporary pressurization, as shown in FIG.
The color selection electrode 16 is placed on the frame upper surface 11c, a tensile force is applied to the color selection electrode 16 in the direction of arrow A, and a compression force in the main pressurization is applied to the frame-shaped frame 10 in the direction of arrow B. To do.

As described above, in the temporary pressure state, the pressure plate upper end 15a needs to be below the frame upper face 11c so that the color selection electrode 16 does not come into contact with the pressure plate upper end 15a. is there. If importance is given to ensuring the frame restoring force, it is ideal that the upper end 15a of the pressure plate is located above the frame upper surface 11c so as to substantially coincide with the upper surface 11c.
However, the upper end 15a of the pressure plate does not necessarily have to be located at such an upper limit position, and the upper end 15a of the pressure plate is located below the upper surface 11c of the frame so that a predetermined frame restoring force can be secured. You may set it.

FIG. 7D is a side view showing the relationship between the long side frame 11 and the pressure plate 15 after the main pressurization.
When the actual pressurization is changed from the temporary pressurization state of FIG. 7C,
The long side frame 11 is curved so as to be further convex and is displaced upward with respect to the pressure plate 15. Therefore, the radius of curvature R6 of the frame upper surface 11c is smaller than the radius of curvature R5 of FIG. 7C. In the above numerical example, the radius of curvature R6 of the frame upper surface 11c after the main pressurization is 6000 mm, which coincides with the radius of curvature R3 of the upper end 15a of the pressure plate. In the present embodiment, the position of the upper end 15a of the pressure plate after the main pressure is set to be 0.5 to 2 mm below the upper surface 11c of the frame.

In the present embodiment, as shown in FIG. 7B, the pressure plate 15 is arranged as high as possible in the frame 11 in anticipation of the upward displacement of the frame 11 with respect to the pressure plate 15. As shown in (d), the relationship of R3 (upper end of pressing plate) = R6 (upper surface of frame 11c) is satisfied.
The distance between the upper end 15a of the pressure plate and the upper surface 11c of the frame is substantially the same over the entire length of the frame 11. Therefore, the pressure surface of the pressure plate 15 extends over the entire length of the pressure plate 15,
This means that the upper end of the long side frame 11 is being pressed.

Therefore, after releasing the compressive force after welding, the restoring force of the frame-shaped frame 10 having substantially the same magnitude as the applied pressure can be obtained, and the color selection electrode 16 is fixed to the frame-shaped frame 10. The subsequent tensile force can be reliably obtained as set.

In FIG. 7D, for ease of explanation, the radius of curvature R6 of the frame upper surface 11c and the radius of curvature R3 of the pressing plate upper end surface 15 after the main pressurization are
Although it has been explained with numerical examples that completely match, after the main pressurization,
The pressure plate 15 is provided over the entire length of the long side frame 11.
Need only apply the upper end of the long-side frame 11, and the effect of the present invention can be exhibited as long as the radii of curvature R6 and R3 substantially match.

After the main pressurization, as shown in FIG.
The color selection electrode 16 is bonded to the long side frame 11 while rotating the roller electrode 20 along the frame upper surface 11c. After the welding, the color selection electrode is cut into a predetermined length to complete a color selection electrode assembly which is a joined body of the frame-shaped frame 10 and the color selection electrode 16 as shown in FIG.

[0065]

As described above, according to the present invention, the radius of curvature of the upper end of the pressure plate and the radius of curvature of the upper surface of the frame after the application of the compressive force are made substantially the same so that the compressive force is applied after the compressive force is applied. It is possible to apply pressure to the upper end of the frame over the entire length of the pressure plate. Therefore, the compressive force can be effectively applied to the frame, and after the compressive force is released, the restoring force of the frame which is almost the same as the applied pressure can be obtained, and the color selection electrode is fixed to the frame. It is possible to reliably obtain the tensile force of the color selection electrode after the setting as set.

Further, by making the radius of curvature of the upper surface of the frame and the radius of curvature of the support when the color selection electrodes are placed substantially equal to each other, it is possible to prevent the occurrence of a gap between the color selection electrode and the upper surface of the frame. Therefore, the length of the color selection electrode in the extending direction is uniform in the curved surface direction of the support over the entire color selection electrode, and even if a tensile force is applied, the color selection electrode is not distorted. Wrinkles can be prevented.

[Brief description of drawings]

FIG. 1 is a sectional view of a color cathode ray tube according to an embodiment of the present invention.

FIG. 2 is a perspective view of a color selection structure according to an embodiment of the present invention.

3A is a perspective view of a frame-like frame according to an embodiment of the present invention, FIG. 3B is a perspective view of a stretching step according to an embodiment of the present invention, and FIG. 3C is welding according to an embodiment of the present invention. Perspective view of process

FIG. 4 is a side view of a stretching step according to the embodiment of the present invention.

FIG. 5 is a perspective view of a stretching step according to an embodiment of the present invention.

FIG. 6A is a cross-sectional view showing a supported state of the color selection electrode after the main pressurization for comparison. FIG. 6B is a cross-sectional view showing a supported state of the color selection electrode according to the embodiment of the present invention.

FIG. 7A is a side view for comparison showing the relationship between the long side frame after the main pressurization and the pressure plate, and FIG. 7B is a side view of the long side frame before the pressurization and the pressurization according to the embodiment of the present invention. Side view showing the relationship with the pressure plate (c) Side view showing the relationship between the long side frame and the pressure plate after temporary pressurization according to one embodiment of the present invention (d) The present application according to one embodiment of the present invention Side view showing the relationship between the long side frame and the pressure plate after pressure

[Explanation of symbols]

6,16 color selection electrode 7,10 Frame-shaped frame 11 long side frame 11c frame top 12 short side frames 13 Chucking device 15 Pressure plate 15a Upper end of pressure plate 18 Support 20 roller electrode

Claims (4)

[Claims] 1. The color selection electrode is applied to the frame in a state where a compression force is applied in a direction in which a space between opposing sides of the frame is reduced and a tension force is applied to the color selection electrode in a direction opposite to the compression force. And a radius of curvature of an end surface of the pressure plate that applies the compressive force on the color selection electrode side, and a radius of curvature of the bonding surface of the color selection electrode of the frame after the application of the compression force. A method for manufacturing a color cathode ray tube, characterized in that: 2. The color selection electrode is applied to the frame in a state where a compression force is applied in a direction in which a space between opposing sides of the frame is reduced and a tension force is applied to the color selection electrode in a direction opposite to the compression force. A joining step of joining is used, and in the stretching step, a support body that supports the color selection electrode by abutting on the frame-side surface of both surfaces of the color selection electrode is used. The radius of curvature of the joint surface of the color selection electrode of the frame when mounted on the support is substantially the same as the radius of curvature of the contact surface of the color selection electrode of the support. And a method for manufacturing a color cathode ray tube. 3. The color selection electrode is applied to the frame in a state where a compression force is applied in a direction in which a space between opposing sides of the frame is reduced and a tension force is applied to the color selection electrode in a direction opposite to the compression force. A step of joining is provided, and in order to apply the tensile force, holding means sandwiching both surfaces of the color selection electrode is used, the color selection electrode is placed on the frame, and the holding means is the color selection electrode. In a state in which both sides are sandwiched, the radius of curvature of the joint surface of the color selection electrode of the frame,
A method for manufacturing a color cathode ray tube, wherein at least a radius of curvature of a surface of the holding means that abuts a surface of the color selection electrode on the frame side is substantially the same. 4. The color selection electrode is applied to the frame in a state where a compression force is applied in a direction in which a space between opposing sides of the frame is reduced and a tension force is applied to the color selection electrode in a direction opposite to the compression force. And a radius of curvature of an end surface of the pressure plate that applies the compressive force on the color selection electrode side, and a radius of curvature of the bonding surface of the color selection electrode of the frame after the application of the compression force. Are substantially the same, in the stretching step, of both surfaces of the color selection electrode, a support that supports the color selection electrode by contacting the surface on the frame side is used, and the color selection electrode is The radius of curvature of the joint surface of the color selection electrode of the frame when mounted on a support and the radius of curvature of the contact surface of the color selection electrode of the support are substantially the same, Holds both sides of the color selection electrode for voltage application Using stage, the color selection electrode is placed on the support, and in the holding means is sandwiched state both sides of the color selection electrode, and the radius of curvature of the cemented surface of the color selecting electrode of said frame,
A method of manufacturing a color cathode ray tube, wherein at least a radius of curvature of a surface of the holding means that abuts a surface of the color selection electrode on the frame side is substantially the same.