JPH07211254A - Color cathode-ray tube - Google Patents

Abstract

PURPOSE:To prevent an electron gun from being tilted due to shock by thickening the diameter of an inner lead wire of a stem pin to be connected to an electrode more than that of an inner lead wire to be connected to a support part. CONSTITUTION:Out of step pins 22a to 22j of a stem 20, the diameter of an inner lead wire 24 of a stem pin 22a to be connected to grids G3 and G5 is thickened more than that of an inner lead wire 24 of stem pins 22b to 22j other than the stem pin 22a to be connected to the grids G3 and G5. Thereby, the stem pin 22a contributes to support an electron gun 7 on the cathode side and the entire circumference of the electron gun 7 is evenly supported from the four directions by setting its thickness properly, so that the electron gun 7 may not tilted even if a shock of approximately 50G is applied to a color cathode-ray tube in a direction perpendicular to the tube axis.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color cathode ray tube, and more particularly to a color cathode ray tube in which an electron gun is prevented from tilting due to impact or the like.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 3, a color cathode ray tube has an envelope composed of a panel 1 and a funnel 2, and faces a shadow mask 3 arranged inside the panel 1 to face the panel 1. A phosphor screen 4 consisting of a phosphor layer of three colors is formed on the inner surface of the, and a three electron beam 8 emitted from an electron gun 7 arranged in a neck 6 of the funnel 2 is attached to the outside of the funnel 2 for deflection. The phosphor screen 4 is deflected by a magnetic field generated by the device 9 and horizontally and vertically scanned to form a structure for displaying a color image.

Among such color cathode ray tubes, an in-line type color cathode ray tube, in which the electron gun 7 is an electron gun which emits three electron beams arranged in a line passing through the same horizontal plane, is currently the mainstream of color cathode ray tubes.

Generally, the electron gun 7 of a color cathode ray tube has three
It has a plurality of cathodes, a heater for heating each of the cathodes individually, and a plurality of electrodes arranged at predetermined intervals in the phosphor screen direction from the cathodes. The cathodes, the heaters, and the plurality of electrodes are rod-shaped insulating supports. It is formed in a structure that is integrally fixed by the body. The electron gun 7 is attached to a plurality of stem pins 12 of a stem 11 whose cathode side is welded to the end of the neck 6, and the phosphor screen 4 side is a bulb spacer made of a plurality of elastic members pressed against the inner surface of the funnel 2. It is supported by (not shown) and is arranged in the neck so as to coincide with the tube axis (z axis).

As an example of such an electron gun 7, a QPF (Qu
adra Potential Focus) type electron gun. This electron gun comprises three cathodes K arranged in a row, heaters H for heating the cathodes K individually, and first to eighth electrodes K which are sequentially arranged from the cathode K in the phosphor screen direction at predetermined intervals.
A structure having grids G1 to G8, in which the cathode K, the heater H, and the first to eighth grids G1 to G8 are integrally fixed via a support portion planted in a pair of rod-shaped insulating supports 14. Has been formed.

The stem 11 has a plurality of stem pins 16 penetrating airtightly on the same circumference of the flare portion 15 at predetermined unequal intervals. In the electron gun shown in FIG. Of the ten stem pins 16a to 16j, three stem pins 16b, 16f and 16i, that is, the stem pin 16b welded to the support portion 18 of the first grid G1,
Stem pin 16f welded to the support 18 of the cathode K
, The stem pin 16i welded to the support portion 18 of the heater H
The cathode K side is supported by a substantially straight inner lead wire 17.

By the way, as described above, the electron gun 7 in which the cathode K side is supported by the stem pins 16a to 16j and the phosphor screen 4 side is supported by the bulb spacers.
Then, when a shock of about 50 G is applied to the color CRT in the direction orthogonal to the tube axis (Z axis) during transportation, the shock causes the beam to tilt as shown by the broken line in FIG. 3 and the beam spot on the phosphor screen 4. It shifts. The deviation of the beam spots is caused by the stem pins 16a to 16 welded to the supporting portion.
If the diameter of the inner lead wire 17 of j is 0.65 mm,
There is a problem that it becomes 0.5 mm or more and the image quality is deteriorated.

As a result of the investigation, it was found that the tilt due to the impact of the electron gun 7 occurs mainly in the direction of the stem pin 16a. This is supported by the three stem pins 16b, 16f, 16i located on the cathode K side of the electron gun 7 in a specific direction, and the support is not averaged over the entire circumference of the electron gun 7, and FIG. In the case of the electron gun 7 shown in FIG. 1, a highly flexible connector wire 19 in which a stem pin 16a capable of averaging its support is welded to an inner lead wire 17 is provided.
This is because they are connected to the third and fifth grids G3 and G5 via the and are hardly contributed to the support of the electron gun 7.

In order to suppress the inclination of the electron gun 7 shown in FIG. 4, as shown in FIG. 5, a supporting portion 18a is planted at the end of the insulating support 14 on the cathode K side, and this supporting portion is formed. 18
The inner lead wire 17 of the stem pin 16a is welded to a, and the entire circumference of the electron gun 7 is connected to the other stem pins 16b, 16f,
16i, and the third and fifth grids G3 and G5 are arranged so as to support them uniformly from four directions.
Although it may be connected by a connector wire via 8a, when the supporting portion 18a is provided at the end of the insulating support 14 on the cathode K side, the supporting portion 18a is implanted into the supporting portion 18 of the cathode K. The distance between the parts is as close as 1-2 mm, and a potential difference of about 7-8 kV occurs between them. As a result, a discharge may occur between the supporting portions 18 and 18a, and the insulating support 14 may cause dielectric breakdown. In order to prevent this dielectric breakdown, the distance between the supporting portions 18a and 18 may be set to 10 mm or more, but if this is done, the total length of the electron gun becomes long, which is a practical problem.

As another means for suppressing the inclination of the electron gun 7 shown in FIG. 4, the inner lead wires 17 of the three stem pins 16b, 16f, 16i for supporting the cathode K side of the electron gun 7 and the third, If the inner lead wire 17 of the stem pin 16a connected to the fifth grid G3, G5 is made thicker by 30%, the inclination of the electron gun 7 can be made to a level at which there is no practical problem, but in this case, the impact applied to the color cathode ray tube. Is transmitted to the electron gun 7 with almost no attenuation, and the welded support portions of the stem pins 16b, 16f, 16i are deformed, and the third and fifth grids G3, G5 connected via the connector wire 19 are deformed. The problem arises.

[0011]

As described above, the electron gun of the color cathode ray tube has the cathode side supported by a plurality of stem pins that hermetically penetrate the stem welded to the neck end, and the phosphor screen side of the funnel. A plurality of valve spacers made of an elastic body pressed against the inner surface are arranged in the neck so as to coincide with the tube axis. However, this electron gun is supported by a stem pin located in a specific direction and is not averaged over the entire circumference of the electron gun, so it is supported when a shock is applied to the color CRT in the direction orthogonal to the tube axis. However, there is a problem that the beam spot on the phosphor screen is deviated and the image quality is deteriorated.

In order to suppress the tilt of the electron gun, another support portion is planted at the cathode side end portion of the insulating support body for integrally fixing the cathode, the heater, the grid and the like through the support portion. , The stem pin located in the above-mentioned unsupported direction may be welded to this support part so as to uniformly support the entire circumference of the electron gun together with the other stem pins. If another support portion is planted at the end portion, electric discharge may occur between the support portion and the adjacent support portion, and the insulating support may cause dielectric breakdown. In order to prevent this dielectric breakdown, it is sufficient to increase the distance from the adjacent support portion, but this makes the total length of the electron gun longer,
It becomes a problem in practical use.

As another means for suppressing the tilt of the electron gun, if the inner lead wire of the stem pin that supports the cathode side of the electron gun is made thicker, it is made about 30% thicker so that there is no practical problem of tilting the electron gun. Although it can be set to a level, in this case, the impact applied to the color cathode ray tube is transmitted to the electron gun without being attenuated, and the deformation of the support part and the electrode welded to the stem pin supporting the cathode side of the electron gun are deformed. The problem arises.

The present invention has been made to solve the above problems, and an object thereof is to prevent the electron gun from tilting even when a shock is applied to the color CRT.

[0015]

A cathode, a heater for heating the cathode, and a plurality of electrodes sequentially arranged in the phosphor screen direction from the cathode, the cathode, the heater and the plurality of electrodes serving as an insulating support. A plurality of electron guns that are integrally fixed via a support portion that is implanted, and a stem in which a plurality of stem pins are arranged at a predetermined interval on the same circumference, The individual support portions and a plurality of stem pins selected from the above stem pins are connected by inner lead wires of these stem pins, and at least one of the plurality of electrodes is directly connected to the inner lead wires of the stem pins without interposing the support portions. In a color CRT that is connected via a connector, it is connected to at least one of a plurality of electrodes either directly or via a connector. The diameter of the inner lead wire stem pins being, is larger than the diameter of the inner leads of stem pins connected to the plurality of support portions that are selected.

Further, in a color cathode ray tube in which a focusing electrode of a plurality of electrodes is connected to an inner lead wire of a stem pin directly or through a connector without a support portion, the focusing electrode is directly or through a connector. The diameter of the inner lead wire of the stem pin to be connected was made larger than the diameter of the inner lead wire of the stem pin to be connected to the selected plurality of supporting portions.

Further, the diameter of the inner lead wire of the stem pin connected to the focusing electrode via the connector is less than 30% larger than the diameter of the inner lead wire of the stem pin connected to the plurality of selected supporting portions. did.

[0018]

As described above, the diameter of the inner lead wire of the stem pin, which is connected to at least one of the plurality of electrodes or the focusing electrode directly or through the connector, is connected to the plurality of selected supporting portions. If the diameter is larger than the diameter of the inner lead wire of the stem pin, the stem pin connected to the selected plurality of supporting portions and the stem pin connected to at least one of the plurality of electrodes or the focusing electrode directly or via the connector The average circumference of the electron gun is supported, and the electron gun can be prevented from tilting even when a shock is applied to the color cathode ray tube.

In particular, if the diameter of the inner lead wire of the stem pin connected to the focusing electrode via the connector is made larger than the diameter of the inner lead wire of the stem pin connected to the selected plurality of supporting portions by less than 30%, Even if an impact is applied to the color cathode ray tube, the deformation of the focusing electrode can be reduced.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described based on embodiments with reference to the drawings.

FIG. 2 shows an in-line type color cathode ray tube which is an embodiment of the invention. This color cathode-ray tube has an envelope made up of a panel 1 and a funnel 2 integrally joined to the panel 1, and a blue,
A phosphor screen 3 composed of a striped three-color phosphor layer that emits green and red is formed, and a shadow mask 3 is arranged inside the phosphor screen 3 so as to face the phosphor screen 3. On the other hand, in the neck 6 of the funnel 2, a QPF that emits a row of three electron beams 8 that pass on the same horizontal plane.
A model electron gun 7 is arranged. Reference numeral 9 is a deflecting device mounted outside the funnel 2.

As shown in FIG. 1, the electron gun 7 includes three cathodes K arranged in a line in the horizontal direction, three heaters H for heating the cathodes K, and a phosphor screen from the cathodes K. The first to eighth grids G1 to G8 (electrodes) are sequentially arranged at predetermined intervals in the direction. In this electron gun 7, the fifth grid G5 serves as a focusing electrode for finally focusing the three electron beams on the phosphor screen. The cathode K, the heater H, and the first to eighth grids G1 to G8 are planted in a rod-shaped insulating support 14 made of a pair of glasses.
It is formed in the structure fixed integrally through 8.

In this electron gun 7, the phosphor screen side is
It is attached to the eighth grid G8 and is supported by a valve spacer (not shown) made of a plurality of elastic members that is pressed against the inner surface of the funnel, and the cathode K side is welded to the end of the neck 6 shown in FIG. The stem 20 is supported by a predetermined stem pin 22 selected from a plurality of stem pins 22 that hermetically penetrate the stem 20.

The stem 20 is, as shown in FIG.
The flare portion 23 has ten stem pins 22a to 22j that penetrate airtightly on the same circumference at predetermined intervals. Of these stem pins 22a to 22j, the third and fifth grids G3 are provided.
, G5, the diameter of the inner lead wire 24 of the other stem pins 22b to 22j excluding the stem pin 22a connected thereto is 0,65 mm, and the inner lead wire 24 of the stem pin 22a connected to the third and fifth grids G3, G5 is The diameter was 0.85mm, which was thicker than that. The inner lead wire 24 extending almost straight from the stem pin 22b
On the support 18 of the first grid G1 and the stem pin 22f
The inner lead wire 24 extending substantially straight is welded to the supporting portion 18 of the cathode K, and the inner lead wire 24 extending substantially straight of the stem pin 22i is welded to the supporting portion 18 of the heater H, and the inner lead wire 24 of the stem pin 22a is welded. It is connected to the third and fifth grids G3 and G5 via a connector 26 composed of a wire. This stem 2
In the connection structure of 0, the inner lead wire 24 of the stem pin 22a is thickened so that the stem pin 22a can be connected to other stem pins 22b. 22f and 22i support the cathode K side of the electron gun.

That is, when the inner lead wire 24 of the stem pin 22a connected to the third and fifth grids G3 and G5 is thickened as described above, the stem pin 22a also becomes thicker.
The electron gun 7 contributes to the support on the cathode K side, and by appropriately setting the thickness thereof, the entire circumference of the electron gun 7 is uniformly supported from four directions, and is orthogonal to the tube axis in the color CRT. It is possible to prevent the electron gun 7 from tilting even when a shock of about 50 G is applied in the direction.

The inner lead wire 24 of this stem 20
Is usually formed of nickel wire, but it is also possible to increase the rigidity by using iron wire, plated iron wire, nickel-chromium alloy wire such as stainless wire.

With respect to the electron gun 7 shown in FIG. 1, four stem pins 22a, 22b.
The diameters of the inner lead wires 24 of 22f and 22i are changed to assemble a color cathode ray tube, and the inclination of the electron gun 7 when a shock of 50 G is applied to the color cathode ray tube in the direction orthogonal to the tube axis is displayed on the phosphor screen 3. Of the stem pin 22b. 22f
Table 1 shows the results of evaluating the deformations of the support portion 25 and the fifth grit G5 welded to the No. 22i. In Table 1, # 1, # 2, # 3 and # 4 are stem pins 22a, 22b. ． 22f and 22i are shown.

[0028]

[Table 1] In Table 1, sample A is a conventional stem in which the diameter of the inner lid wire of each stem pin is 0.65 mm. In this case, the fifth grit is not deformed, but the beam spot is displaced by 0.5 mm or more, which is a practical problem, as described above.

Sample B includes stem pins 22a, 22b. The diameter of the inner lead wires of 22f and 22i is 15%, and that of sample C is 30% thicker. In the case of sample B, even if the diameter of the inner lead wire of stem pin 22a is 15% thicker, No deformation occurs, but the beam spot is still between 0.1 and
A 0.5 mm deviation causes a practical problem. On the other hand, when the diameter of the inner lead wire is increased by 30% as in Sample C, the deviation of the beam spot can be reduced to 0.1 mm or less, which is practically no problem, but in this case,
Deformation occurs in the fifth grit.

In Sample D, the diameter of the inner lead wire of the stem pin 22a is made 15% thicker than that of the conventional stem,
Other stem pin 22b. This is the stem of this embodiment in which the inner lead wires of 22f and 22i have the same diameter as the conventional stem, and the deviation of the beam spot is 0.1 mm or less.
The grit is not deformed, which indicates that it is practically possible. However, like sample E, the stem pin 22a
30% of inner lead wire diameter compared to conventional stem
If it is made thicker, the strength of the inner lead wire becomes too large and the other stem pins 22b. Although the balance with 22f and 22i is lost and the fifth grit is not deformed, the beam spot is deviated by 0.1 to 0.5 mm, which is a practical problem.

Samples F to H are made up of stem pins 22b. This is the case where the diameter of any one of the inner lead wires 22f and 22i is made 15% thicker than the inner lead wire of the conventional stem. In this way, the stem pin 22b. Two
If any one of the inner lead wires 2f and 22i is thickened, the balance of the strength with the other stem pins 22a is lost and the beam spot is displaced, which is a practical problem.

That is, the inner lead wire 24 of the stem pin 22b connected to the fifth grit G5 is connected to the other stem pins 22b. 22f
, 22i have the same inner lead wire 24,
By making the thickness 30% or less, and optimally 15% thicker than that, it is possible to reduce the deviation of the beam spot on the phosphor screen 3 to a practical level without deforming the fifth grit G5.

In the above embodiment, the in-line type color cathode ray tube equipped with the QPF type electron gun has been described. However, the present invention has an in-line type color cathode ray tube equipped with an electron gun other than the QPF type electron gun, and a color other than the in-line type color cathode ray tube. It can be applied to the cathode ray tube when the inner lead wire of at least one stem pin is directly connected to the electrode of the electron gun through a connector.

[0034]

INDUSTRIAL APPLICABILITY The diameter of the inner lead wire of the stem pin which is connected to at least one of the plurality of electrodes or the focusing electrode directly or through the connector is set to the inner diameter of the stem pin which is connected to the plurality of selected supporting portions. If the diameter is larger than the diameter of the lead wire, the electron gun may include a stem pin connected to a plurality of selected support portions and at least one of the plurality of electrodes or a stem pin directly connected to the focusing electrode or through a connector. Thus, the electron gun can be prevented from tilting even when a shock is applied to the color CRT, and deviation of the beam spot on the phosphor screen can be prevented.

Particularly, by making the diameter of the inner lead of the stem pin connected to the focusing electrode via the connector less than 30% larger than the diameter of the inner lead wire of the stem pin connected to the plurality of selected supporting portions. Even when an impact is applied to the color cathode ray tube, the electron gun is prevented from tilting, deformation of the focusing electrode can be reduced, and a highly reliable color cathode ray tube in which the focus characteristic does not change can be obtained.

[Brief description of drawings]

FIG. 1 (a) is a front view showing the connection between an electron gun and a stem of a color cathode ray tube according to an embodiment of the present invention, and FIG. 1 (b) is a view as seen from the stem side.

FIG. 2 is a diagram showing a configuration of a color CRT which is an embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of a conventional color CRT.

FIG. 4 (a) is a front view showing the connection of a conventional color CRT with an electron gun and a stem, and FIG. 4 (b) is a view seen from the stem side.

5A and 5B are views for explaining a problem in connection between a focusing electrode and a stem pin of a conventional color CRT electron gun.

[Explanation of symbols]

 4 ... Phosphor screen 6 ... Neck 7 ... Electron gun 14 ... Rod-shaped insulating support 18 ... Support 20 ... Stem 22 ... Stem pin 24 ... Inner lead wire 26 ... Connector G1 ... First grid G2 ... Second grid G3 ... Third Grid G4 ... 4th grid G5 ... 5th grid G6 ... 6th grid G7 ... 7th grid G8 ... 8th grid H ... Heater K ... Cathode

Claims (3)

[Claims] 1. A cathode, a heater for heating the cathode, and a plurality of electrodes sequentially arranged in the phosphor screen direction from the cathode. The cathode, the heater and the plurality of electrodes are implanted in an insulating support. A plurality of supports selected from the above-mentioned supporting parts, and an electron gun integrally fixed via the supporting parts, and a stem in which a plurality of stem pins are arranged at predetermined intervals on the same circumference. Section and a plurality of stem pins selected from the stem pins are connected by inner lead wires of the stem pins, and at least one of the plurality of electrodes is directly connected to the inner lead wire of the stem pin without interposing the support portion. In a color cathode ray tube connected through a connector, at least one of the plurality of electrodes, directly or through a connector. Color CRT in which the diameter of the inner lead wire stem pins to be connected being greater than the diameter of the inner leads of stem pins connected to the plurality of support portions that are the selected Te. 2. A cathode, a heater for heating the cathode, and a plurality of electrodes including a focusing electrode sequentially arranged in the phosphor screen direction from the cathode, the cathode, the heater and the plurality of electrodes being an insulating support. An electron gun integrally fixed via a support part implanted in the, and a stem in which a plurality of stem pins are arranged at predetermined intervals on the same circumference, and selected from the above support parts. A plurality of support portions and a plurality of stem pins selected from the stem pins are connected by inner lead wires of these stem pins, and the focusing electrode is directly or directly connected to the inner lead wires of the stem pins without interposing the support portions. In the color CRT which is connected via the stem pin of the stem pin which is directly connected to the focusing electrode or through the connector. Color CRT in which the diameter of N'narido line being greater than the diameter of the inner leads of stem pins connected to the plurality of support portions that are above selected. 3. The diameter of the inner lead wire of the stem pin connected to the focusing electrode via the connector is less than 30% larger than the diameter of the inner lead wire of the stem pin connected to the plurality of selected supporting portions. Claim 2 characterized by the above-mentioned.
Color CRT as described.