JP3063651B2 - Fluorescent display tube and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent display tube having a reinforcing column for preventing an envelope hermetically sealed in a high vacuum state from being deformed by external atmospheric pressure, and a fluorescent display tube having the same. It relates to a manufacturing method.

[0002]

2. Description of the Related Art A general fluorescent display tube has a lid-shaped container portion consisting of a front plate and a frame-shaped side plate sealed to a base substrate, and has a box-shaped outer portion hermetically sealed in a high vacuum state. It has an enclosure. Inside the envelope, an anode having a phosphor is formed on the surface of the base substrate, a control electrode is provided above the anode, and a plurality of filament cathodes for emitting electrons are provided above the control electrode. Is provided.

[0003] In the thus constructed fluorescent display tube, when the filamentary cathode is heated and electrons are emitted from the cathode, the electrons are accelerated and controlled by the control electrode and strike the anode. As a result, the phosphor is excited and emits light, and a desired display is performed.

A fluorescent display tube of this type has a structure in which a base substrate and a front plate are fixed only at an outer peripheral portion by a frame-shaped side plate, and each substrate (base substrate) constituting an envelope is provided. , Front plate and side plate) to increase the thickness to some extent to obtain strength. Specifically, in the conventional fluorescent display tube, the thickness of each substrate is set to 3.5 mm.

However, simply increasing the thickness of each of the substrates constituting the envelope causes atmospheric pressure to be applied from the outside to the base substrate and the wall surface of the front plate. Can not stand. For this reason, the structure which arrange | positions the support | pillar for reinforcement in several places in an envelope, and supports between boards, ie, between a base board and a front plate, is adopted.

FIG. 3 is a side sectional view of a conventional fluorescent display tube provided with reinforcing columns. In FIG.
1 is an anode 32 so as not to disturb the display pattern.
Are disposed at two places on the left and right of the base substrate 34 in the envelope 33 so as to avoid this. The reinforcing column 31 is formed in a quadrangular prism shape, and one end surface 31 a is fixed to the base substrate 34 by the fixing paste 35, and the other end surface 31 b is fixed to the front plate 37 by the low melting point paste 36. As the fixing paste 35, an intermediate paste for the control electrode 38 applied to the base substrate 34 is also used. Further, the low melting point paste 36 is applied to the other end surface 31b of the reinforcing column 31 in advance.

In manufacturing the fluorescent display tube on which the reinforcing columns 31 are provided, a low-melting-point paste 36 is applied to one side surface of a strip-shaped thin plate, baked, and cut at predetermined intervals (for example, 4 mm). By doing so, a plurality of square pillar-shaped reinforcing columns 31 having the low melting point paste 36 applied to the other end surface 31b are formed.

At the time of assembly, the reinforcing posts 3 are placed on the fixing paste 35 applied to the base substrate 34.
1 is fired and solidified in a state where one end face 31a is placed and erected. Thereby, one end surface 31 a of the reinforcing column 31 is fixed on the base substrate 34. Next, the lid-shaped container portion 39 is arranged on the base substrate 34, and heated by applying pressure from above and below. As a result, the low melting point paste 40 applied to the base substrate 34 and the low melting point paste 36 applied to the reinforcing columns 31 are melted. When the low-melting pastes 40 and 36 are cooled and solidified, the base substrate 34 is cooled.
Between the outer peripheral portion of the support column and the container portion 39, and the other end surface 31b of the reinforcing column 31 is fixed to the front plate 37.

As described above, in the conventional fluorescent display tube, the contact surface (the other end surface 31) of the reinforcing column 31 with the front plate 37 is provided.
The low-melting-point paste 36 was applied to b), and the variation in height of the reinforcing columns 31 when the low-melting-point paste 36 was fixed to the front plate 37 was absorbed by the molten low-melting-point paste 36.

[0010]

However, the above-mentioned conventional fluorescent display tube provided with a reinforcing column has the following problems.

(1) Base substrate 3 inside envelope 33
4, the reinforcement columns 31 are provided only at two places on the left and right sides, and the strength is maintained by the reinforcement columns 31 provided at the two places on the left and right sides of the base board 34. Must be bigger. Specifically, the width is set to about 4 mm × 1.8 mm and the height is about 5.4 mm. For this reason, when observing the display from the front plate 37 side, the viewing angle becomes narrow and it is difficult to see.

(2) Since the reinforcing columns 31 are formed of a glass substrate having the same light-transmitting properties as the respective substrates constituting the envelope 33, the light emission of the display pattern leaks from the side surface and is affected by reflection. This makes the display difficult to read.

(3) The reinforcing column 31 is fixed to the front plate 37 with a low-melting paste 36, and the low-melting paste 36 melted at the time of fixing adheres around the other end 31b of the reinforcing column 31. Since it is extended out, the viewing angle when observing the display from the front plate 37 side is narrowed, making it difficult to see.

(4) Since the number of reinforcing columns 31 provided in the envelope 33 is reduced and the thickness of each substrate constituting the envelope 33 is increased, the overall weight is increased. Specifically, the thickness of each of the base substrate 34, the front plate 37, and the side plate 41 is 3.5 mm, and the weight when a 60 mm × 220 mm fluorescent display tube is manufactured is 270 g.

(5) Since the reinforcing pillar 31 has a surface on which the low-melting-point paste 36 is applied (the other end surface 31b) and a surface on which the low-melting-point paste 36 is not applied (one end surface 31a), a step of separating these surfaces is required. Since it is necessary, it is difficult to automatically align the plurality of reinforcing columns 31 all at once by vibration.

(6) The low melting point paste 36 is applied to one surface (the other end surface 31b) of the reinforcing column 31 in a separate step of forming the reinforcing column, so that the cost per column becomes high. .

If the low-melting-point paste 36 applied to the reinforcing columns 31 is deleted to solve the above-mentioned problems, the front plate 3 may be removed due to variations in the height of the reinforcing columns.
There is a problem that a reinforcing column which does not contact with 7 is generated and does not function as a reinforcing column.

Further, when trying to reduce the thickness and weight of the fluorescent display tube, the number of the reinforcing columns 31 is insufficient in the above-mentioned conventional fluorescent display tube, and the fluorescent display tube cannot sufficiently withstand external pressure. In this case, it is necessary to dispose a plurality of reinforcing columns 31 on the base substrate 34 so as not to interfere with the display pattern, that is, to avoid the anode 32. For this purpose, the reinforcing column 31 may be made sufficiently small. However, the reinforcing column 31 used in the conventional fluorescent display tube has a low melting point paste 36 applied to one surface (the other end surface 31b). For,
It takes time and effort to align on the base substrate 2.

In view of the above, the present invention has been made in view of the above-mentioned problems, and a reinforcing column is provided on a front plate side without using a low-melting-point paste in a state where the reinforcing column is securely in contact with the front plate. The present invention aims to provide a fluorescent display tube capable of absorbing variations in height of a support column, observing a display without reducing a viewing angle, and achieving a thin, lightweight, efficient work and reduced cost, and a method of manufacturing the same. And

[0020]

In order to achieve the above object, according to the present invention, an anode forming a display pattern is formed on a base substrate, and a control electrode is located above the anode and the control electrode is formed on the base substrate. Is fixed by a fixing paste that is not re-melted, and a lid-shaped container portion including a front plate and a frame-shaped side plate is sealed to the outer peripheral portion of the base substrate. In a fluorescent display tube provided with a device, at a portion avoiding the anode in the envelope, one end surface is in contact with the inner surface of the front plate, and the other end surface is applied on the base substrate and pre-baked. A reinforcing column is fixed on the base substrate via a low-melting paste and a non-remelting fixing paste used also for fixing the control electrode disposed so as to sink into the low-melting paste. It is characterized by the following.

According to a second aspect of the present invention, in the fluorescent display tube of the first aspect, the reinforcing column is made of a glass material mixed with a black pigment.

According to a third aspect of the present invention, a low-melting-point paste is applied to an outer peripheral portion of a base substrate on which an anode forming a display pattern is formed, and reinforcing columns are provided on the base substrate at locations avoiding the anode. A step of applying a low-melting paste to a place to be provided and pre-baking, and applying a non-remelting fixing paste for fixing a control electrode positioned above the anode to the base substrate on the base substrate. Applying a non-remelting fixing paste, which is also used for fixing the control electrode, onto a low melting paste applied to a portion of the base substrate avoiding the anode; and fixing on the low melting paste. The reinforcing posts are erected on the paste for fixing, the fixing paste is baked and solidified, the control electrode is fixed on the base substrate, and the reinforcing posts are fixed on the fixing paste. Temporarily fixing and heating by applying pressure from above and below in a state where a lid-shaped container portion composed of a front plate and a frame-shaped side plate faces the base substrate, and the reinforcing column is temporarily fixed. The fixing paste is submerged in the low-melting paste, the container is sealed to the outer peripheral portion of the base substrate to form an envelope, and the reinforcing column is pressed into contact with the inner surface of the front plate. Fixing between the base substrate and the front plate.

[0023]

FIG. 1 is a side sectional view showing one embodiment of a fluorescent display tube according to the present invention.

The fluorescent display tube has an envelope 1 whose inside is hermetically maintained in a high vacuum state, and has a structure in which various electrodes and the like are housed.

The envelope 1 includes a base substrate 2 made of a glass substrate, a front plate 3, and a frame-shaped side plate 4. The envelope 1 includes a front plate 3 having insulation and translucency.
By forming a lid-shaped container portion 5 from the insulating frame-shaped side plate 4 and sealing the container portion 5 on the outer peripheral portion of the insulating base substrate 2 with a sealing agent, It is evacuated to a high vacuum and kept airtight.

An anode conductor 6 of Al or the like is formed on the inner surface of the base substrate 2, a phosphor layer 7 is formed on the anode conductor 6, and an anode 8 having a predetermined pattern shape is defined. I have. A mesh-shaped control electrode 9 is provided above the anode 8, and a filament-shaped cathode 10 is provided above the control electrode 9. The filament cathode 10 emits electrons by heating, and the control electrode 9 controls the acceleration of the electrons emitted from the filament cathode 10 toward the anode 8 forming a display pattern.

On the base substrate 2 in the envelope 1, thin reinforcing columns 11 having a quadrangular prism shape are arranged at a plurality of locations. Each reinforcing column 11 is fixed between the base substrate 2 and the front plate 3 in a state of being pressed against the front plate 3 while avoiding the anode 8 forming a display pattern so as not to hinder display. Specifically, when manufacturing a 60 mm × 220 mm fluorescent display tube, 34 reinforcing columns 11 are provided.

The height of the reinforcing column 11 is slightly higher than the height of the side plate 4, and the outer dimensions are set smaller than those of the conventional one. As specific external dimensions,
The width is set to 1 mm × 1 mm and the height is 4.4 mm.
In addition, the support | pillar 11 for reinforcement is not limited to a square pillar shape,
Other shapes such as a polygonal pillar shape and a cylindrical shape may be used.

The reinforcing column 11 is formed by, for example, mixing a black pigment with a glass material and press-molding it. Thereby, the reinforcing columns 11 are formed in black of the same color as the background of the base substrate 2, and when the display is observed from the front plate 3 side, each reinforcing column 11 is buried in the background of the base substrate 2 and stands out. Nothing. Also, light emission of the display pattern leaks from the side,
Since the display is not affected by the reflection, the display is easy to see and the visibility is excellent as compared with the conventional fluorescent display tube shown in FIG.

A low-melting paste 12 as a fixing agent is applied to a position on the base substrate 2 where the reinforcing column 11 is to be provided. When the low melting point paste 12 is fixed to the base substrate 2 to form the envelope 1, the low melting point paste 12 is applied together with the operation of applying the low melting point paste 13 to the outer peripheral portion of the base substrate 2.

As the low-melting paste 12, a paste having a softening point of 380 ° C. containing frit glass as a main component is used.

On the low melting point paste 12, the reinforcing columns 1
1 for fixing the one end face 11a
Is applied. The fixing paste 14 is used together with an operation of applying an intermediate paste for fixing the control electrode 9 to the base substrate 2. The fixing paste 14 is
Once the old song is used, the paste for attaching the control electrode 9 that does not melt again is also used.

Each reinforcing column 11 has one end face 11
a is fixed on the fixing paste 14 via the low-melting paste 12 fixed on the base substrate 2, and the other end surface 11 b is pressed between the base substrate 2 and the front plate 3 with the inner surface of the front plate 3. And supports between the base substrate 2 and the front plate 3. This prevents the envelope 1 from being deformed by external atmospheric pressure.

Next, a method of manufacturing the fluorescent display tube having the above-described configuration will be described. First, the anode 8 partitioned into a predetermined shape forming a display pattern is formed on the base substrate 2. More specifically, although not specifically shown, Al is patterned on the base substrate 2 to print and form a wiring, and an insulating layer with through holes is printed and formed on the wiring. Then, the through hole of the insulating layer is filled with Ag paste, and the anode conductor 6 is formed on the through hole.
The phosphor layer 7 is formed on the upper surface by printing.

Next, a low melting point paste 13 is applied to the outer peripheral portion of the base substrate 2 on which the anode 8 is formed. At this time, the low-melting-point paste 12 is also applied to the portion of the base substrate 2 where the reinforcing columns 11 are to be provided, and these low-melting-point pastes 12 and 13 are preliminarily fired (FIG. 2A). Subsequently, an intermediate paste for fixing the control electrode 9 to the base substrate 2 is applied onto the base substrate 2. At this time, the intermediate paste is used as the fixing paste 14, and the reinforcing columns 11 are used.
Is applied together on the low melting point paste 12 on which is disposed (FIG. 2B).

Next, the control electrode 9 is placed on the paste for attachment, and the control electrode 9 is fixed to the base substrate 2. continue,
One end surface 11a of the reinforcing column 11 is placed on the fixing paste 14, and the reinforcing column 11 is erected on the fixing paste 14 and temporarily fixed (FIG. 2C). An automatic alignment machine (not shown) is used for placing the reinforcing columns 11 on the fixing paste 14. In the automatic alignment machine, a plurality of reinforcing columns 11 are sorted by vibration in accordance with the arrangement position, and automatic alignment is simultaneously performed. Then, the fixing paste 14
Is fired and solidified. As a result, one end surface 11 a of each reinforcing column 11 is fixed on the fixing paste 14.

Here, a frame on which the filament-shaped cathode 10 is stretched is assembled in a process different from the above operation. Then, the bottom peripheral surface of the side plate 4 in the container portion 5 is positioned on the outer peripheral portion of the base substrate 2 to which the low melting point paste 13 has been applied (FIG. 2D), and the base substrate 2 and the container portion 5 are vertically positioned. Pressure is applied to seal the outer peripheral portion of the base substrate 2 and the container portion 5 to assemble the envelope 1 (FIG. 2E).

Here, in the assembling work of the envelope 1, the thin reinforcing strut 11 is fixed to the fixing paste 14 whose lower surface (the other end surface 11b) is solidified, and the base substrate 2 and the container When a force is applied to the part 5 from above and below, the fixing paste 14 sinks into the low melting point paste 12 melted by the pressing force of the front plate 3 (FIG. 2).
(E)). As a result, height variations of the reinforcing columns 11 are absorbed.

Thereafter, the inside of the envelope 1 is evacuated to a high vacuum state and sealed to complete the fluorescent display tube.

As described above, according to the fluorescent display tube of the above embodiment, the solidified fixing paste 1 on the base substrate 2
The reinforcing column 11 fixed to 4 is pressed into the low-melting paste 12 that is melted at the time of firing when the envelope 1 is assembled.

Therefore, as in the prior art, the reinforcing columns 11
The height variation of the reinforcing posts 11 can be absorbed by the low-melting paste 12 applied to the base substrate 2 side without applying the low-melting paste to the surface on the front plate 3 side. 3 can be fixedly provided between the base substrate 2 and the front plate 3 in a state where the contact is securely made.

Since the reinforcing pillars 11 as parts do not need to be distinguished between the upper and lower surfaces as in the prior art, it is possible to perform automatic alignment all at once by an automatic alignment machine.

Each reinforcing column 11 is formed to have a smaller outer dimension than the conventional one, and no low-melting-point paste is used between the reinforcing column 11 and the front plate 3. The restriction of the viewing angle due to sag can be reduced as compared with the conventional fluorescent display tube shown in FIG.

The reinforcing column 11 is formed only of a glass material, and it is not necessary to apply a low-melting paste to one surface in advance as in the prior art, so that the cost can be reduced.

Since the reinforcing columns 11 are formed in the same color black as the background of the base substrate 2, each of the reinforcing columns 11 is buried in the background of the base substrate 2 when observing the display from the front plate 3 side. Not noticeable. In addition, it is possible to provide a fluorescent display tube which is easy to see and has excellent visibility compared to the conventional fluorescent display tube shown in FIG. it can.

Since a plurality of reinforcing columns 11 whose outer dimensions are set smaller than in the prior art are arranged in the envelope 1,
The fluorescent display tube can be made thinner and lighter than before. Specifically, when manufacturing a 60 mm × 220 mm fluorescent display tube, the reinforcing columns provided in the envelope 1 are:
Conventional width 4mm × 1.8mm, height 5.4mm to width 1
mm × 1 mm and height 4.4 mm.

As a result, the thickness of each of the substrates (the base substrate 2, the front plate 3, and the side plate 4) constituting the envelope 1 is reduced from the conventional 3.5 mm to 1.8 mm, and the thickness of the side plate 4 is reduced. The height is also reduced from 5.2 mm to 4 mm. As a result, the weight of the fluorescent display tube can be reduced from 270 g to 150 g.

Also, as the height of the side plate 4 is reduced and the thicknesses of the base substrate 2 and the front plate 3 are reduced, the vertical viewing angle is wider than that of the conventional fluorescent display tube.

[0049]

As is apparent from the above description, according to the present invention, the height variation of the reinforcing columns is achieved without applying a low-melting-point paste to the front-plate-side surface of the reinforcing columns as in the prior art. Can be absorbed, and the reinforcing columns can be fixedly provided between the base substrate and the front plate in a state where they are securely contacted with the front plate.

Since the reinforcing columns as components do not need to be distinguished between the upper and lower surfaces as in the prior art, it is possible to perform automatic alignment all at once by an automatic alignment machine.

Since the low-melting-point paste is not used between the reinforcing column and the front plate, even if the outer dimensions of the reinforcing column are made smaller than before, the viewing angle due to the sagging of the low-melting-point paste as in the prior art can be reduced. Restrictions can be reduced compared to conventional fluorescent display tubes. Moreover, the thinning and weight reduction of the fluorescent display tube can be achieved by arranging a plurality of reinforcing columns provided in the envelope, which are thinner than the conventional ones.

The reinforcing column is formed only of a glass material,
Since it is not necessary to apply a low-melting-point paste on one surface in advance as in the related art, cost can be reduced.

Since the reinforcing columns are formed in black of the same color as the background of the base substrate, when the display is observed from the front plate side, each reinforcing column is not buried in the background of the base substrate and does not stand out. . In addition, it is possible to provide a fluorescent display tube that is easy to view and has excellent visibility compared to a conventional fluorescent display tube without emission of a display pattern leaking from a side surface or being affected by reflection.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing an embodiment of a fluorescent display tube according to the present invention.

2 (a) to 2 (e) are views showing a manufacturing process for arranging reinforcing columns of the fluorescent display tube.

FIG. 3 is a side sectional view of a conventional fluorescent display tube having a reinforcing column.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Envelope, 2 ... Base board, 3 ... Front plate, 4 ... Side plate, 5 ... Container part, 8 ... Anode, 11 ... Reinforcement support, 12 ...
Low melting point paste, 14: paste for fixing.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-8-148101 (JP, A) JP-A-8-83579 (JP, A) JP-A 7-142015 (JP, A) JP-A-6-14859 342630 (JP, A) JP-A-8-138554 (JP, A) JP-A-7-326306 (JP, A) JP-A-4-289646 (JP, A) JP-A-1-164656 (JP, U) Japanese Utility Model Application Hei 4-21049 (JP, U) Japanese Utility Model Application Hei 1-62642 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01J 31/15 H01J 9/24 H01J 9/26 H01J 29/86

Claims (3)

(57) [Claims] An anode forming a display pattern is formed on a base substrate, and a control electrode is located above the anode and the control electrode is located on the base substrate.
Paste that does not re-melt on the base substrate
A fluorescent display tube further comprising a box-shaped envelope in which a lid-shaped container portion formed of a front plate and a frame-shaped side plate is sealed on an outer peripheral portion of the base substrate ; the position that avoids the anode of the envelope, in contact with the inner surface of one end face is the front plate, low melting paste and low melting paste in the other end surface is to calcined coating on the base substrate Of the control electrode disposed so as to be submerged in
Through a non-remelting fixing paste that is also used for
A fluorescent display tube having a reinforcing column fixed on a base substrate . 2. The fluorescent display tube according to claim 1, wherein the reinforcing column is made by mixing a black pigment with a glass material. 3. A low-melting-point paste is applied to an outer peripheral portion of a base substrate on which an anode forming a display pattern is formed, and reinforcing columns are provided on the base substrate at positions avoiding the anode.
Work to apply low-melting paste to the place where it will be installed and to temporarily bake
And a control electrode located above the anode on the base substrate.
The fixing paste that does not re-melt for fixing is
Coated on a base substrate, and the anode on the base substrate
The control electrode is placed on the low-melting paste applied to
Apply a non-remelting fixing paste that is also used for fixing the poles.
A step of fabric, the front with erected the reinforcing strut on the fixing paste on low melting paste solidified by firing the fixing paste, to fix the control electrode on the base substrate
Temporarily fixing the reinforcing column on the fixing paste
And pressing and heating from above and below in a state in which a lid-shaped container portion composed of a front plate and a frame-shaped side plate faces the base substrate, the fixing paste to which the reinforcing columns are temporarily fixed, The container is sealed to the outer peripheral portion of the base substrate by being immersed in a low-melting paste to form an envelope, and the reinforcing column is brought into pressure contact with the inner surface of the front plate to contact the base substrate. method for manufacturing a fluorescent display tube which comprises a step of fixedly between the front plate.