JPH11283535A - Method and apparatus for manufacturing cathode ray tube - Google Patents

Abstract

[PROBLEMS] To provide a method and an apparatus for manufacturing a cathode ray tube in which a plurality of funnels can be accurately set at predetermined positions and which have improved withstand voltage characteristics and vacuum tightness characteristics. A rear envelope having a side wall, a rear plate, and a plurality of funnels integrally formed by molding a softened sheet glass with a molding die. The molding die has a plurality of divided first molding portions 41a and second molding portions 41b. The first molding portions are connected to each other by first coupling portions 42a, and the second molding portions are coupled to each other by second coupling portions 42b. Linked to each other. The first and second molded portions are formed of a material having excellent moldability and mold release properties of glass, and the first and second connecting portions are formed of a material having a thermal expansion coefficient close to that of glass.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phosphor screen having a face plate having a phosphor screen formed on an inner surface, a rear plate facing the face plate, and a plurality of electron guns attached to the rear plate. The present invention relates to a method and an apparatus for manufacturing a cathode ray tube which scans a plurality of areas by scanning a plurality of areas.

[0002]

2. Description of the Related Art In recent years, various studies have been made on high-definition broadcasting or a high-resolution cathode ray tube having a large screen accompanying this. Generally, in order to achieve high resolution of a cathode ray tube, the spot diameter of an electron beam on a phosphor screen must be reduced.

[0003] On the other hand, conventionally, an attempt has been made to improve the electrode structure of an electron gun or to enlarge and extend the diameter of the electron gun itself, but no satisfactory results have yet been obtained. The biggest cause of this is that the distance from the electron gun to the phosphor screen increases as the size of the cathode ray tube increases, and the magnification of the electron lens becomes too large. Therefore, it is important to reduce the distance (depth) from the electron gun to the phosphor screen in order to realize high resolution. Further, if the deflection angle of the electron beam is wide, the magnification difference between the center and the periphery of the screen increases. For this reason, wide-angle deflection is not advantageous for achieving high resolution.

In order to solve the above-mentioned problems of the conventional cathode ray tube, for example, Japanese Patent Application Laid-Open No. 5-363 is disclosed.
As disclosed in JP-A-63-63, a face plate and a rear plate are formed flat, and a phosphor screen having an integrated structure formed on an inner surface of the face plate is emitted from a plurality of electron guns attached to the rear plate. There has been developed a cathode ray tube which scans by dividing into a plurality of regions by using the obtained electron beam.

More specifically, this type of cathode ray tube includes a flat glass face plate and a rear plate which are opposed to each other in parallel with each other, and a joining material such as frit glass or the like is provided on the periphery of the face plate. The glass sidewalls are joined and extend vertically. The rear plate is fixed to the face plate via the side wall. In the rear plate, a plurality of rectangular openings are formed corresponding to a plurality of regions of the phosphor screen which are divided and scanned. A plurality of funnels are fixed to the rear plate so as to surround the openings, respectively, with a bonding material, and the electron gun is sealed in the neck of each funnel.

[0006] The integrated phosphor screen formed on the inner surface of the face plate is divided into a plurality of regions and scanned by electron beams emitted from the plurality of electron guns. Images drawn in each area by the divided scanning are connected by controlling signals applied to an electron gun and a deflection device mounted corresponding to each electron gun, so that there is no break or overlap in the entire area of the phosphor screen. Play the image.

[0007]

As described above, in a cathode ray tube which scans a fluorescent screen by dividing it into a plurality of regions by electron beams emitted from a plurality of electron guns,
To obtain an image in which the raster of each area has a predetermined size and there is no break or overlap between adjacent areas, place the electron gun precisely at a predetermined position so that the axis of each electron gun passes through the center of the corresponding area. Must be placed.

However, when joining a plurality of funnels to the rear plate, it is necessary to join them with high precision so that the axis of the electron gun sealed in the neck of each funnel passes through the center of each region as described above. Is not easy and very difficult. Further, a plurality of funnels and side walls must be fixed to the glass rear plate with a bonding material, and this bonding portion reduces the positional accuracy of each member,
This may cause a decrease in reliability such as withstand voltage characteristics and vacuum hermetic characteristics.

The present invention has been made in view of the above points, and has as its object to provide a plurality of funnels on a rear plate facing a face plate and a plurality of funnels sealed in the neck of each funnel. A plurality of funnels are accurately set at predetermined positions in a cathode ray tube that scans by dividing an integrated phosphor screen having an inner surface of a face plate into a plurality of regions by an electron beam emitted from an electron gun. It is an object of the present invention to provide a method and apparatus for manufacturing a cathode ray tube, which is capable of improving a withstand voltage characteristic and a vacuum hermetic characteristic while being capable of improving a withstand voltage characteristic and a vacuum airtight characteristic.

[0010]

In order to achieve the above object, a manufacturing method according to the present invention comprises a substantially rectangular face plate having a phosphor screen formed on an inner surface thereof;
A substantially rectangular rear plate opposed to the face plate via a side wall, a plurality of funnels extending from the rear plate, and a plurality of necks respectively extending from the funnel. A cathode ray tube for scanning the phosphor screen by dividing the phosphor screen into a plurality of regions by electron beams emitted from a plurality of electron guns disposed in the neck, wherein the plurality of funnels are formed. A plurality of forming parts, and a connecting part connecting the plurality of forming parts to each other, using a forming die in which the forming part and the connecting part are formed of materials having different coefficients of thermal expansion, a single It is characterized in that the rear plate and the plurality of funnels are integrally formed from a sheet glass. Further, the manufacturing apparatus according to the present invention includes a substantially rectangular face plate having a phosphor screen formed on an inner surface thereof, and a substantially rectangular rear plate disposed to face the face plate via a side wall. A plurality of funnels extending from the rear plate, and a plurality of necks respectively extending from the funnels, and an electron beam emitted from a plurality of electron guns disposed in the necks. An apparatus for manufacturing a cathode ray tube that scans the phosphor screen by dividing the phosphor screen into a plurality of regions by using a beam, has a lower mold and an upper mold that can be opened and closed, and uses a single sheet of glass to form the side wall, the rear plate, and the plurality of funnels. And a plurality of first molding portions for molding the inner surface of the side wall, the plurality of funnels, and the rear plate, and A first connecting portion that connects the first forming portions to each other, wherein the upper mold cooperates with the first forming portion to form the outer surface of the side wall, the plurality of funnels, and the rear plate. A second molding part; and a second coupling part that couples the second molding parts to each other. The first coupling part and the second coupling part are formed of materials having the same thermal expansion coefficient. The part and the second molding part are characterized in that they are formed of materials having different thermal expansion coefficients from the first connection part and the second connection part.

[0011] According to the manufacturing method and the manufacturing apparatus having the above-described structure, a molding die for integrally molding a plurality of funnels and a rear plate from a single sheet glass is connected to a plurality of molding portions for molding a funnel and the molding portion. And the formed portion and the connected portion are formed of materials having different thermal expansions.
For example, the forming portion uses a material having excellent moldability and mold release properties of glass, and the connecting portion uses a material similar to the thermal expansion of glass at the time of glass forming. Thereby, it is possible to avoid the displacement of the funnel caused by the difference in the thermal expansion between the glass and the molded portion, and it is possible to precisely mold the axis of the electron gun sealed in the neck of each funnel to a predetermined position. it can.

Further, it is possible to avoid breakage of the glass caused by a difference in thermal expansion between the glass and the mold. Furthermore, since the funnel is integrally formed with the rear plate, the bonding surface of each member is reduced, the reliability such as withstand voltage and vacuum tightness is greatly improved, and the cost of materials and man-hours involved in bonding are also reduced.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings. First, the configuration of a cathode ray tube manufactured by the manufacturing method and the manufacturing apparatus of the present invention will be described.

As shown in FIGS. 1 and 2, the cathode ray tube comprises a vacuum envelope 7, which comprises a substantially rectangular flat glass face plate 1 and a face plate 1 made of glass. A frame-like side wall 2 joined to a peripheral portion of the base plate 1 with a bonding material such as frit glass and extending substantially perpendicular to the face plate 1, and substantially opposed to the face plate 1 through the side wall 2 in parallel. The rear plate 3 has a rectangular flat glass rear plate 3 and a plurality of funnels 4 extending from the rear plate 3. The funnels 4 are arranged in a matrix, for example, five in the horizontal direction (X direction) and four in the vertical direction (Y direction), for a total of 20 funnels.
Are provided.

Such a vacuum envelope 7 includes the face plate 1 and a rear envelope 10. The rear envelope 10 is a structure in which the side wall 2, the rear plate 3, and the funnel 4 are integrated, and is joined to the face plate 1 by a joining material to form the vacuum envelope 7. Side wall 2
Is bent outward at a substantially right angle to form a flange 2a. The vacuum envelope 7 is formed by joining the flange 2a and the face plate 1 using, for example, frit glass.

On the inner surface of the face plate 1, a stripe-shaped three-color phosphor layer extending in the vertical direction Y and emitting blue, green, and red light, and a black stripe provided between the three-color phosphor layers are provided. A phosphor screen 8 having an integral structure is formed.

In the neck 5 of each funnel 4,
An electron gun 12 that emits an electron beam toward the phosphor screen 8 is sealed. Further, a deflection device 14 is attached to the outer periphery of each funnel.

Between the face plate 1 and the rear plate 3, there are arranged a plurality of plate supporting members 16 for supporting the atmospheric pressure applied to the face plate 1 and the rear plate 3 of the vacuum envelope 7. Plate support member 16
Is formed by a cylindrical metal rod. The tip of each plate support member 16 is formed in a knife edge shape,
It is in contact with the black stripe of the phosphor screen 8. In particular, each plate support member 16 is disposed such that the tip thereof abuts on the intersection of the boundaries between adjacent scanning regions of the phosphor screen 8 described later. The base end of each plate support member 16 is in contact with a reference surface 18 formed at a predetermined position on the inner surface of the rear plate 3 and is fixed by frit glass.

By providing the plate supporting member 16 having such a structure, sufficient atmospheric pressure intensity can be obtained even if the face plate 1, the side wall 2, the rear plate 3 and the like are each made of glass having a thickness of 4 to 15 mm. The weight of the vacuum envelope 7 can be greatly reduced.

In the cathode ray tube configured as described above, the electron beams emitted from the plurality of electron guns 12 are deflected by the magnetic field generated by the deflecting device 14 mounted outside each of the funnels 4, and the fluorescent screen 8 Is divided into a plurality of regions, in the illustrated example, five in the horizontal direction and four in the vertical direction, that is, divided into 20 regions R1 to R20 for scanning. An image drawn on the phosphor screen 8 by the divided scanning is connected by a signal applied to the electron gun 12 and the deflecting device 14 to reproduce one large image without any breaks or overlaps on the entire surface of the phosphor screen 8. I do.

Next, a method of manufacturing the cathode ray tube having the above-described structure and a manufacturing apparatus used for implementing the method will be described. First, the glass sheet used as the material of the rear vacuum envelope 10 is heated to a temperature equal to or higher than the softening point of the glass to be softened, and the softened glass sheet is formed into a predetermined shape by a molding die described later. Thereby, as shown in FIG. 3, the side wall 2, the rear plate 3, and the funnel 4 are integrally formed. The plurality of funnels 4 formed on the rear plate 3 are each formed into a funnel shape, and the glass on the neck side is thinner. In addition, the side wall 2 has an end on the face plate side bent outward at a right angle to form a flange 2 a, and has a shape that allows a wide bonding width when bonding to the face plate 21. In addition, since a glass pool is formed at the tip end of the funnel 4 after molding, this portion is cut.

Next, as shown in FIG.
Of these inner surfaces, these portions are polished so that all portions where the plurality of plate support members 16 are arranged are located on the same plane, and a flat concave reference surface 18 is processed. Subsequently, a neck 5 previously processed into a flared shape is connected to the tip of each funnel 4. The funnel 4 and the neck 5 are connected by welding by burner heating. Thereby, the rear envelope 10 is completed.

Subsequently, the plurality of plate support members 16 are positioned with respect to the reference surface 18 of the rear plate 3 using a jig, and the base end of the plate support member 16 is positioned on the reference surface 18 by applying and firing frit glass. Fix it. Further, the electron gun 12 is sealed in the plurality of necks 5. Further, after the phosphor screen 8 is formed on the inner surface of the face plate 1, the rear envelope 10 and the face plate are integrally joined by applying and firing a frit glass using an assembling jig to form a vacuum envelope. 7 is formed. After that, the vacuum envelope 7 is evacuated to complete the cathode ray tube. Next, a molding die used for molding the rear envelope 10 will be described. As shown in FIG. 5, the molding die 40 includes a lower die 40a and an upper die
0b. The lower mold 40a has a first forming portion 41a for forming the inner surface of the side wall 2, the inner surface of the rear plate 3, and the inner surface of the funnel 4, and a first connecting portion 42a of a rectangular plate shape connecting these first forming portions to each other. And
These first forming portions 41a are used in the same number as the corresponding funnels 4, that is, 20 in this embodiment. In addition, upper mold 4
0b is a second forming portion 41b for forming the outer surface of the side wall 2, the outer surface of the rear plate 3, and the outer surface of the funnel 4, a rectangular plate-shaped second connecting portion 42b connecting these second forming portions to each other, have. The number of the second forming portions 41b is the same as the number of the corresponding funnels 4 similarly to the first forming portion 41a, and in the present embodiment, 20 are used.

Each first forming portion 41a is formed in a prismatic shape,
A convex portion 44a is integrally formed on the upper surface side. The projection 44a is formed in a substantially conical shape corresponding to the funnel 4. The side surfaces of the fourteen first forming portions 41a located at the ends in the X direction and the Y direction are formed in a shape corresponding to the inner surface of the side wall 2. Also, each first forming part 4
A recess 45 a is formed on the surface opposite to the molding surface of 1 a, that is, on the bottom surface, and is located on the central axis C of the funnel 4.

On the upper surface of the first connecting portion 42a, 2
Zero ribs 46a are formed, and each is located on the central axis C of the funnel 4. The twenty first forming portions 41a are fixed on the first connecting portions 42a in a state where the respective recesses 45a are fitted to the ribs 46a.
As a result, the first forming portions 41a are connected to each other by the first connecting portions 42a, and are also connected in the X direction and the Y direction.
They are lined up with a gap of about 1 mm in the direction. Further, a side wall 4 extending vertically upward is provided on a peripheral portion of the first connecting portion 42a.
7 is erected.

On the other hand, each of the second molded portions 41b is formed in a prismatic shape, and a concave portion 44b is formed on the lower surface thereof. These recesses 44 b are formed in a substantially conical shape corresponding to the funnel 4. The side surfaces of the 14 second molded portions 41b located at the ends in the X direction and the Y direction are formed in a shape corresponding to the outer surface of the side wall 2. A depression 45 b is formed on the surface opposite to the molding surface of each second forming portion 41 b, that is, on the upper surface, and is located on the center axis C of the funnel 4.

On the lower surface of the second connecting portion 42b,
Zero ribs 46b are formed, and are located on the central axis C of the funnel 4, respectively. The twenty second forming portions 41b are fixed to the second connecting portions 42a in a state where the respective recesses 45b are fitted to the ribs 46b. Thus, the second forming portions 41b are connected to each other by the second connecting portion 42b, and are arranged with a gap of about 1 mm in the X direction and the Y direction. Further, a side wall 48 extending vertically downward is erected at the peripheral edge of the second connecting portion 42b, and is slidably fitted to the side wall 47 of the first connecting portion 42a.

When molding the rear envelope 10 using the molding die 40 having the above-described configuration, the lower mold 40a and the upper mold 40b are opened, and softened between the first molding portion 41a and the second molding portion 41b. After disposing the glass sheet 30, the lower mold and the upper mold are closed, and the glass sheet 30 is sandwiched between the molding surface of the first molding portion 41a and the molding surface of the second molding portion 41b. In this state, the mold 4
By heating the entirety 0 to a high temperature, the rear envelope 10 having a predetermined shape is formed. In the present embodiment, the first and second forming portions 41a and 41b and the first and second connecting portions 42a and 42b are formed of materials having different coefficients of thermal expansion. That is, the first and second forming portions 41
The first and second connecting portions 42a and 42b are made of a carbon material having a thermal expansion coefficient of about 30 × 10 ⁻⁷ / ° C.
b is a nickel alloy material having a thermal expansion coefficient close to the thermal expansion coefficient of glass (about 90 × 10 ⁻⁷ / ° C.) (for example, 50
% Nickel steel). In forming a large-sized vacuum envelope as in the present embodiment, the amount of thermal expansion of glass is as large as 1 mm or more for a cathode ray tube equivalent to 30 inches. In order to absorb this difference in thermal expansion, the thermal expansion of the entire mold 40 must be approximated to that of glass as in the present embodiment.

Further, if the entire mold 40 is made of a material similar to the thermal expansion of glass, the problem of destruction due to the difference in thermal expansion does not occur, but it is difficult to release the glass from the mold. Considering the releasability, it is desirable that the thermal expansion coefficient between the glass and the formed part is somewhat apart. If the coefficients of thermal expansion match completely, the glass and the mold may be sealed (adhered). In the present embodiment, since each second molding die 41b has a gap between the glass and the molding die in the cooling process after the glass molding, no external force is applied to the rear envelope. On the other hand, each of the first forming portions 41a applies an external force (tensile stress) to the glass in the cooling process after the glass is formed. However, since the rear envelope can slide upward from the forming die 40, the glass is prevented from being broken. You can do it.

As described above, according to the present embodiment, the side wall 2, the rear plate 3, and the plurality of funnels 4
Are formed integrally from a single sheet of glass, and the first and second forming portions 41a and 41b that are in contact with the glass are formed of a carbon material having excellent mold release properties.
By forming the 2a and 42b from a material having a thermal expansion coefficient similar to that of glass, a plurality of funnels 4 can be formed at a predetermined position with high precision without breaking the glass. Finally, the position of the electron gun sealed in each neck 5 of the funnel 4 can also be set accurately.

In a cathode ray tube for displaying a screen by dividing the screen into a plurality of areas, one of the conditions for preventing the connection of the screens from being invisible is that an electron beam actually emitted from an electron gun is used. And the axis (normal axis) passing through the center of each divided and displayed area must be matched.

To accurately set the trajectory of the electron beam,
The relationship between the electron gun and the neck, the relationship between the rear vacuum envelope 10 and the face plate 1 (phosphor screen), and the mutual positional relationship between the plurality of funnels 4 must all be set with high precision.

The relationship between the electron gun 12 and the neck 5 can be easily maintained at a high level because the position of the electron gun can be corrected at room temperature in the step of sealing the electron gun to the neck. The rear vacuum envelope 10 and the face plate 1 are compared by using a method in which a part of the outer shape of both parts is pressed against a reference pad of a firing jig as a reference position (each three points) and bonded with frit glass. High accuracy can be easily maintained.

The mutual positional relationship between the plurality of funnels 4 is the relative positional relationship between the side wall 2, the rear plate 3, and the funnel 4 that constitute the rear vacuum envelope 10. Since the funnel 4 is integrally formed, the relative position of the funnel 4 is determined by the structure, material, and processing accuracy of the forming part used for the forming die, and the manufacturing method and the manufacturing apparatus (forming die) having the above-described configuration are used. Thereby, the rear envelope 10 can be formed with high accuracy without being affected by the difference in the thermal expansion coefficient of each member.

The relationship between each funnel 4 and the reference position of the rear vacuum envelope 10 can be corrected after polishing the side wall 2, the rear plate 3, and the funnel 4 by correcting the reference position 18 by a method such as polishing. Does not.

Further, the trajectory of the electron beam is determined by the emission position of the electron beam and its emission angle, and the emission position is the position of the electron gun. receive. Thus, even if the axis of the electron gun is arranged at a predetermined position, the trajectory of the electron beam does not always match the predetermined trajectory. Therefore, conventionally, as a method of correcting the trajectory of the electron beam to a predetermined trajectory, the trajectory of the electron beam is corrected and corrected using a ring-shaped magnet. Therefore, the trajectory of the electron beam can be corrected to some extent by variously combining the correction by the magnet. What is important here is that if this correction is used excessively, the electron beam shape will be distorted, and for example, a high-resolution image cannot be reproduced. In order to perform the correction relatively easily and accurately without affecting the beam shape of the electron beam, the inventors have set the arrangement accuracy of the electron gun to approximately 0.5.
mm or less.

In order for the positioning accuracy of the electron gun, that is, the positioning accuracy of the funnel, to satisfy the above-mentioned values, the amount of misalignment caused by the difference in thermal expansion between the molding die and the glass material in the present embodiment is equal to or less than the above-mentioned values. However, the actual displacement is 0.05 mm or less, and the present embodiment makes it possible to manufacture a cathode ray tube having a highly accurate vacuum envelope.

As described above, according to the cathode ray tube manufacturing method and the molding die according to the present embodiment, the molding die for molding the rear envelope includes a plurality of molding parts for molding the funnel and these molding parts. The molded part is made of carbon material with excellent moldability and mold release properties of glass, and the joint part is made of nickel alloy material that is similar to the thermal expansion of glass during glass molding. By doing so, it is possible to avoid the misalignment of the funnel caused by the difference in thermal expansion between the glass and the molded part, and mold the electron gun sealed in the neck of each funnel so that it precisely matches the predetermined position with the predetermined position. can do. Further, breakage of the glass caused by a difference in thermal expansion between the glass and the mold can be avoided, and the releasability of the glass can be maintained and improved. Furthermore, by integrally molding the funnel with the rear plate, the bonding surface of each member is reduced, the reliability such as withstand voltage and vacuum tightness is greatly improved, and the cost of materials and man-hours involved in bonding are also reduced. Can be.

The present invention is not limited to the above-described embodiment, but can be variously modified within the scope of the present invention. For example, in the above-described embodiment, the first and second forming portions 41a and 41b are formed of a carbon material,
Although a nickel alloy material was used as a material for forming the second connecting portions 42a and 42b, the present invention is not limited to this, and various materials can be selected as needed. May be used in combination.

For example, the first forming part 41a uses HCF (manufactured by Toshiba), the second forming part 41b uses carbon material, and the first and second connecting parts 42a and 42b use the heat of the glass during the glass forming. A nickel alloy material that approximates expansion can also be used. HCF has poor wettability to glass and excellent releasability, and has a larger coefficient of thermal expansion than glass. Therefore, as in the above-described embodiment, the first molding portion 41a exerts an external force on the glass during the cooling process after glass molding. Since no (tensile stress) is applied, there is no need to slide the rear envelope upward from the mold 40 during the cooling process, and the molding process is simplified.

In addition, the material for forming the first and second molded portions 41a and 41b may be ceramic (for example,
(Macerite CSP: manufactured by Mitsui Mining Materials) and other metals. Further, it goes without saying that various materials having a thermal expansion coefficient close to the thermal expansion coefficient of glass can be selected as a material for forming the first and second connecting portions 42a and 42b.

Further, in the above-described embodiment, the mold 4
The first and second molded portions 41a and 41b of the first embodiment are entirely formed of a material having excellent releasability. However, as shown in FIG. 7, the main body 50 of each molded portion is obtained at low cost. It may be formed of a material that is easy to use, for example, a nickel alloy material, and only the contact portion 52 that comes into contact with glass may be formed of a material having excellent moldability and mold release properties.

In the above-described embodiment, when the neck 5 and the funnel 4 are connected, the neck is flared in advance and then welded to the funnel with a burner. This method is effective when the funnel 4 is formed from a thick plate glass or when the funnel 4 is welded to a thin neck. Further, in the above-described embodiment, the case where the side wall, the rear plate, and the funnel are integrally formed has been described. However, only the rear plate portion including the funnel may be formed, and the separately formed side wall may be joined. Furthermore, although the face plate side end of the side wall is bent to the outer peripheral side, when the end can secure a width or flatness sufficient for bonding,
As shown in FIG. 6, a shape without a flange may be used. Further, in the present embodiment, a cathode ray tube having a structure without a shadow mask has been described, but the present invention can be applied to another type of cathode ray tube such as a beam index regardless of the presence or absence of a shadow mask. it can.

Further, the first and second molding dies 41a, 41
1b has a configuration of 20 divisions, respectively. For example, when the difference in thermal expansion coefficient between glass and a molding die is small in a small cathode ray tube or the like, the number of divisions of the molding section can be reduced. As a forming method to which the present invention is applied, a method in which a sheet glass and a forming die are set in a forming furnace and the glass is formed at a temperature equal to or higher than the softening temperature of the glass, or a mold and glass are heated in an open air with an electric heater, a gas burner, a high frequency, and a current It can be applied to a method of heating and molding.

[0045]

As described in detail above, according to the present invention, a plurality of funnels can be accurately set at predetermined positions, and a cathode ray tube capable of improving withstand voltage characteristics and vacuum hermetic characteristics can be manufactured. A method and an apparatus for manufacturing the same can be provided.

[0046]

[Brief description of the drawings]

[0047]

FIG. 1 is a perspective view showing a cathode ray tube manufactured by a manufacturing method and a manufacturing apparatus according to an embodiment of the present invention.

[0048]

FIG. 2 is a sectional view taken along the line AA in FIG. 1;

[0049]

FIG. 3 is a sectional view showing a manufacturing process of a rear envelope of the cathode ray tube.

[0050]

FIG. 4 is an exploded sectional view showing the cathode ray tube.

[0051]

FIG. 5 is a sectional view showing a molding die according to the embodiment of the present invention.

[0052]

FIG. 6 is a sectional view showing a manufacturing process of a rear envelope according to a modification of the present invention.

[0053]

FIG. 7 is a sectional view showing a forming portion of a molding die according to a modification of the present invention.

[0054]

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Face plate 2 ... Side wall 3 ... Rear plate 4 ... Funnel 5 ... Neck 7 ... Vacuum envelope 8 ... Phosphor screen 10 ... Rear envelope 12 ... Electron gun 16 ... Plate support member 18 ... Reference surface 30 ... Sheet glass 40 ... Mold 40a ... Lower mold 40b ... Upper mold 41a ... 1st molding part 41b ... 2nd molding part 42a ... 1st connection part 42b ... 2nd connection part

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Susumu Hoshika 5358, Kawajiri, Yoshida-cho, Haibara-gun, Shizuoka Prefecture Inside Shiba Glass Co., Ltd. (72) Inventor Makoto Shiratori 5east of 3583 Kawajiri, Yoshida-machi, Harihara-gun, Shizuoka Prefecture Inside Shiba Glass Co., Ltd. (72) Inventor Takashi Kadari 5-5358 Kawajiri, Yoshida-cho, Haibara-gun, Shizuoka Prefecture

Claims (10)

[Claims] A substantially rectangular face plate having a phosphor screen formed on an inner surface thereof; a substantially rectangular rear plate disposed to face the face plate via a side wall; An envelope having a plurality of extended funnels and a plurality of necks respectively extending from the funnel is provided, and the phosphor is formed by an electron beam emitted from a plurality of electron guns disposed in the neck. A method of manufacturing a cathode ray tube that scans a screen by dividing the screen into a plurality of regions, comprising: a plurality of forming portions for forming the plurality of funnels; and a connecting portion for connecting the plurality of forming portions to each other; The rear plate and the plurality of funnels are integrally formed from a single sheet of glass using a mold in which the connecting portions are formed of materials having different coefficients of thermal expansion. A method for manufacturing a cathode ray tube, characterized by being shaped. 2. The method for manufacturing a cathode ray tube according to claim 1, wherein the side wall, the rear plate, and the plurality of funnels are integrally formed from a single sheet of glass using the molding die. 3. The method for manufacturing a cathode ray tube according to claim 2, further comprising a step of joining the integrally formed side wall, rear plate, and funnel to the face plate with a joining material. 4. A substantially rectangular face plate having a phosphor screen formed on an inner surface thereof, a substantially rectangular rear plate disposed to face the face plate via a side wall, and: An envelope having a plurality of extended funnels and a plurality of necks respectively extending from the funnel is provided, and the phosphor is formed by an electron beam emitted from a plurality of electron guns disposed in the neck. In a cathode ray tube manufacturing apparatus that divides a screen into a plurality of areas and scans, a mold having an openable lower mold and an upper mold, and integrally molding the rear plate and a plurality of funnels from a single sheet of glass. The lower mold includes a plurality of first forming portions that form the inner surfaces of the plurality of funnels and the rear plate, and a plurality of first forming portions that connect the first forming portions to each other. Has a connecting portion, and the upper mold,
A plurality of second forming portions for forming the outer surfaces of the plurality of funnels and the rear plate; and a second connecting portion for connecting the second forming portions to each other.
The connecting portion is formed of a material having a coefficient of thermal expansion close to the coefficient of thermal expansion of the glass, and the first forming portion and the second forming portion have different thermal expansion coefficients from the first connecting portion and the second connecting portion. An apparatus for manufacturing a cathode ray tube, which is formed of a material. 5. The cathode ray tube according to claim 4, wherein said first molded portion is made of a material having a larger coefficient of thermal expansion than said first connecting portion and said second connecting portion. Manufacturing equipment. 6. The cathode ray tube according to claim 4, wherein said second molded portion is made of a material having a smaller coefficient of thermal expansion than said first connecting portion and said second connecting portion. Manufacturing equipment. 7. The method according to claim 1, wherein the first molding portions are provided side by side with a predetermined gap therebetween, and the second molding portions are provided side by side with a predetermined gap therebetween. Item 7. An apparatus for manufacturing a cathode ray tube according to any one of Items 4 to 6. 8. The method according to claim 4, wherein the side wall, the rear plate, and the plurality of funnels are integrally formed from a single sheet of glass using the molding die. A method for manufacturing a cathode ray tube. 9. A substantially rectangular face plate having a phosphor screen formed on an inner surface thereof; a substantially rectangular rear plate disposed to face the face plate via a side wall; An envelope having a plurality of extended funnels and a plurality of necks respectively extending from the funnel is provided, and the phosphor is formed by an electron beam emitted from a plurality of electron guns disposed in the neck. In a cathode ray tube manufacturing apparatus that divides a screen into a plurality of areas and scans, a mold having an openable lower mold and an upper mold, and integrally molding the rear plate and a plurality of funnels from a single sheet of glass. The lower mold includes a plurality of first forming portions that form the inner surfaces of the plurality of funnels and the rear plate, and a plurality of first forming portions that connect the first forming portions to each other. Has a connecting portion, and the upper mold,
A plurality of second forming portions for forming the outer surfaces of the plurality of funnels and the rear plate; and a second connecting portion for connecting the second forming portions to each other.
The connecting portion is formed of a material having a coefficient of thermal expansion close to the coefficient of thermal expansion of the glass, and the first or second molded portion is provided with a contact portion in contact with the sheet glass, having excellent mold releasability from the glass. An apparatus for manufacturing a cathode ray tube, wherein a material is formed. 10. The method for manufacturing a cathode ray tube according to claim 9, wherein the side wall, the rear plate, and the plurality of funnels are integrally formed from a single sheet glass using the molding die.