JPH0656740B2 - Resistor with built-in cathode ray tube - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a resistor incorporated in a cathode ray tube for obtaining a predetermined division voltage, and more particularly to a structure of the resistor.

[Technical background of the invention and its problems]

Generally, about 20 KV for a cathode ray tube such as a color picture tube.
In addition to the anode high voltage of 30 to 30 KV, for example, a medium voltage of about 5 KV to 8 KV is required as the focus voltage of the electron gun, and in the case of a mask focusing type color picture tube, a high voltage slightly lower than the anode high voltage. is necessary. Supplying such a medium-high voltage other than the anode high voltage from the outside of the tube causes a big problem mainly in the withstand voltage of the supply unit. Therefore, there are many inconveniences such as a complicated structure of the supply unit. Therefore, a method of arranging a resistor in the cathode ray tube and dividing the high voltage of the anode by this to obtain the required middle and high voltages, for example, is described in Japanese Utility Model Publication 48-215.
61, Japanese Utility Model Publication No. 55-38484 and U.S. Pat. No. 3,93
2,786, U.S. Pat. No. 4,143,298 and the like.

When the resistor is arranged in the cathode ray tube in this manner, the resistor must be small because there is not enough space for arranging the large resistor in the tube. Also about 25 KV or
Since the anode high voltage of 30KV is divided, it is necessary to suppress the power consumption, so the resistance value must be considerably large. However, in a small-volume resistor having a large resistance value, it is very difficult to suppress manufacturing variations in the resistance value. The highly practical resistor as described above is mainly composed of a palladium / ruthenium oxide, and it is particularly preferable that a mixture of ruthenium oxide and glass is printed in a zigzag pattern on an insulating substrate such as a ceramic. , The resistance value of such a resistor usually varies about ± 10%.
It is possible to suppress the variation up to about ± 1% by strictly controlling the manufacturing, but it is extremely difficult to further suppress the variation.

Such a variation in the resistance value of the resistor also results in a variation in the division voltage obtained depending on the ratio of the resistance values, and eventually means for adjusting the variation in the division voltage must be provided outside the tube.

As the adjusting means provided outside the tube, there are a variable resistor and a low-voltage power source, but since the resistance value of the resistor inside the tube is extremely high as described above, the adjusting means provided outside the tube must also have a considerably high impedance. . However, it is extremely difficult in practice to manufacture a variable resistor or a low voltage source having such a high impedance, and providing an adjusting means outside the tube is economically costly when using a cathode ray tube.

[Object of the Invention]

In view of the above-mentioned points, the object of the present invention is to provide a resistor with a built-in cathode ray tube, which can suppress the variation of the division voltage to a small value even if the resistance value of the resistor greatly varies, and is particularly divided outside the tube. It is to eliminate the need to provide a means for adjusting the variation in voltage.

[Outline of Invention]

The cathode ray tube built-in resistor of the present invention has a region for adjusting the variation of the resistance value in the electrode lead-out portion, and adjusts the division voltage by changing the position of contact of the connector, thereby achieving the above object. To do.

Example of Invention

 Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 5 is a schematic configuration of a main part of a conventional electron gun for a color picture tube having a built-in resistor. In FIG. 5, the electron gun (1)
Has a plurality of electrodes (to be described later) and a plurality of insulating supports (2) for supporting them, and is enclosed in a glass cylindrical neck (18).

The plurality of electrodes project red, green and blue color phosphors 3
A row of cathodes (9a), (3a), (3b), (3c) for generating three electron heaters (6a), (6b), (6c), respectively, for generating the electron beams (3a), (3b), (3c). 9b), (9c), and a first grid (11) and a second grid (11) having a unified structure (unitized structure) with predetermined electron beam passage holes projecting at positions corresponding to these three cathodes. 12), 3rd grid (13), 4th
It is composed of a grid (14) and a convergence electrode (15), and they are fixed to the insulating support (2) by implantation in this order.

The first grid (11) and the second grid (12) are plate-like electrodes that are arranged close to each other, and the third grid (13) is the second grid (1).
2 electric cup-shaped electrodes (23a), which are placed near and joined to 2),
(23b), the fourth grid (14) is the third grid.
It is composed of two cup-shaped electrodes (24a) and (24b) which are arranged at a predetermined distance from (13) and are joined together.
5) consists of one cup-shaped electrode (25a) welded and fixed to the fourth grid (14). Each of the grid electrode and the convergence electrode is provided with three circular electron beam passage holes aligned with each electron beam on the bottom surface of the cup-shaped electrode and the flat electrode.

A valve spacer (17) is applied to the convergence electrode (15), which is applied to an anode terminal (not shown), passes through the internal conductive film (16) and applies a high voltage E _b of about 25 KV.
Further, a resistor (50) is installed near the electrode, and one end (51) of this resistor (50) is connected to the convergence electrode (15) and the other end (5
3) is a stem pin (19) provided at the bottom of the neck (18)
Externally through the variable resistor (49) and the connectors (61), (6
3) is connected via. The stem pin (19) supports and fixes the electron gun, and also the convergence electrode (15) and the fourth electrode.
Each grid potential other than the grid (14) can be externally supplied through the stem pin (19). The appropriate position (52) of the resistor (50) is in contact with the third grid (13) via the connector (62). Therefore, electrically, as shown in FIG. 7, the electrode potential of about 8 KV of the third grid (13) is about 25 KV of high voltage E _b applied to the convergence electrode (15) and the fourth grid (14). It is given as a division potential by the resistor (50), whereby the electron beam is focused on the predetermined screen.

FIG. 6 is a perspective view including a partial cross section of the resistor (50) described in FIG. 1, and the resistor (50) is an insulating substrate such as a ceramic.
The resistance material (55) is arranged on the (54) in a zigzag pattern, and the first, second, and third electrode lead-out portions (71), (72), (73) are provided at predetermined positions, respectively. ing. An insulating material (56) made of glass or the like is coated on the surface of the resistance material (55) except for the electrode extraction portion.

The resistance material (55) was composed mainly of ruthenium oxide 50
A high resistance value of about 0 MΩ to 5000 MΩ is suitable, and the electrode extraction parts (71), (72), (73) are mainly made of a ruthenium oxide having a resistance much lower than that of the resistance material (55). A conductive paint containing silver or gold is suitable. The electrodes (71), (72), (73) are fitted with connectors (61), (62), (63) made of elastic material, respectively, as shown in FIG. Form an electrical circuit. Therefore, the resistor (50) is two resistors
When the variable resistance (49) is divided into R ₁ and R ₂ and the variable resistance (49) is set to 0Ω, the potential of the electrode extraction part (62), that is, the third grid (13) is divided by this division ratio R ₂ / (R ₁ + R ₂ ). Decided. However, the resistance value of the resistor (50) is usually manufactured with a variation of about ± 10%, and it can be suppressed to ± 1% by strict control, but the variation within ± 1% is possible. It is extremely difficult to control. Therefore, the division voltage also varies by ± 1% or more. On the other hand, in the electron gun as described above, the third grid (1
The manufacturing variation of the potential of 3), that is, the focus voltage is usually about ± 0.2% of the anode voltage, and this variation does not significantly deteriorate the electron beam spot diameter on the screen and is generally Although it is within the allowable range for a color picture tube for televisions, the division voltage, that is, a variation of ± 1% of the focus voltage is not acceptable. Therefore, the variable voltage (49) placed outside the tube divides the voltage. Must be adjusted.

Therefore, in the present invention, the variation of the divided voltage is controlled to be within the range of ± 1%, and the variation of the division voltage is suppressed within the above-mentioned practically allowable range.

1 to 3 are views corresponding to the conventional examples of FIGS. 5 to 7 when the present invention is carried out, respectively, and the same parts are denoted by the same reference numerals.

As shown in FIG. 1 and FIG. 2, the resistor (50) is
The third large electrode extraction part (71), (72), (73) is provided,
The first and second large electrode lead-out portions (71), (72) are equivalent to the conventional electrode lead-out portions (71), (72) shown in FIGS. 5 and 6, but
The third large electrode extraction part (73) has 10 small electrode extraction parts (8
3 ₁ ), (83 ₂ ), ..., (83 ₁₀ ) are provided. Then, the same connectors (61), (62) as the conventional connectors are fitted to the first and second large electrode extraction parts (71), (72), but the third large electrode extraction part (71 73) has two connectors (63-a) and (63-a) as connecting members.
b) is fitted.

One of the connectors (63-a) is connected to the small electrode (83 ₁₀ ) at the end of the resistor, and the other connector (63-b) is the appropriate one of the remaining small electrodes. Connect to one small electrode.

By connecting in this way, the electric circuit as shown in FIG. 3 is constructed, and the resistance value R ₁ from the first extraction portion (71) to the second extraction portion (72) and the second extraction portion (72) Part (72) to third extraction part (73)
The resistance value R ₃ up to one small extraction part of
The potential of (72) will be determined.

As can be seen from Figs. 2 and 3, the resistance value R ₃ is the connector (63-b).
Depends on which of the ten small electrode lead-out portions (83 ₁ ) to (83 ₁₀ ) of the third large electrode lead-out portion (73) is connected.

Therefore, a resistor (50 ') with a variation in resistance of ± 1%
It is possible to suppress the variation of the divided voltage taken out from the second take-out portion (72) within ± 0.2% by using.

That is, the connector (63-b) is connected to the resistor (50) having a resistance value of ± 1%.
When mounting, the position of the connector (63-b) is determined so that the divided voltage of the second extraction part (72) is within a predetermined range.

As described above, the variation of the electric potential of the second take-out portion (72), that is, the third grid (13) can be suppressed within ± 0.2% without providing any adjusting means outside the tube.

Therefore, in a general color picture tube for televisions, the focus voltage adjustment is not necessary outside the tube.

In the above-mentioned embodiment, the divided voltage extracting portion is 1 for simplification.
However, the present invention is not limited to this and may be provided at a plurality of locations. Further, although only one large electrode extraction portion having the small electrode extraction portion is provided, the present invention is not limited to this, and a similar small electrode extraction portion may be provided in another large electrode extraction portion. Needless to say.

Further, in the present invention, it goes without saying that adjustment means for fine adjustment may be provided outside the pipe.

Further, in the above embodiment, an example in which the small electrode lead-out portion is divided into several parts is shown, but the present invention is not limited to this, and the resistance material (94) is exposed as shown in FIG. 4, and this is used as the small electrode portion. The connector (64) may be moved on this to adjust the resistance value. The resistor (50) in FIG. 4 corresponds to that in FIG. 2 and the same elements are designated by the same reference numerals.

In FIG. 4, the third large electrode lead-out portion (73) is the small electrode lead-out portion (9).
3 ₁ ), (94), (93 ₂ ), and the upper and lower electrode extraction parts (93 ₁ ), (9
3 ₂ ) is a resistance material or a metallic material having a resistance significantly lower than that of the resistance material (55), and the central electrode extraction portion (94) is the resistance material of the same quality as the resistance material (55) or a resistance value slightly changed. . In such a case, the connector (64) can be continuously varied on the extraction part (94), and the resistance value can be adjusted more accurately.

Further, in the above-mentioned embodiment, one of the electrode potentials of the electron gun is supplied by the divided voltage by the resistor, but the present invention is not limited to this, and the screen portion, the mask portion, and When the inner surface of the funnel has different potentials, or when a plurality of masks having different potentials are used in the mask portion, at least one of these potentials is given as a divided potential by the resistor from the anode high voltage supplied from the outside. Sometimes the invention can be used.

〔The invention's effect〕

As described above, according to the present invention, when one of the potentials required for the cathode ray tube is supplied by the division voltage by the resistor built in the tube, the division voltage of the resistance value of the resistor varies due to manufacturing variations. It is possible to suppress an unacceptable variation within an allowable range, and therefore, it is possible to provide a cathode ray tube with a high economical efficiency, without particularly providing a means for adjusting the unacceptable variation of the division voltage outside the tube. .

[Brief description of drawings]

1 is a schematic configuration diagram showing the vicinity of a neck portion of a cathode ray tube to which the present invention is applied, FIG. 2 is a partially cutaway perspective view showing the resistor of FIG. 1, and FIG. 3 is an electrical configuration of FIG. FIG. 4 is a partially cutaway perspective view showing a resistor according to another embodiment of the present invention, FIG. 5 is a schematic configuration view showing the vicinity of a neck portion of a conventional cathode ray tube, and FIG. 6 is shown in FIG. FIG. 7 is a partially cutaway perspective view showing the resistor, and FIG. 7 is an electrical configuration diagram of FIG. (49) …… External adjustment resistor, (50) …… Built-in resistor (71), (72), (73) …… Large electrode outlet (83 ₁ ) to (83 ₁₀ ) …… Small electrode outlet Part (61), (62), (63) …… Connector

Claims (1)

[Claims] 1. An insulating substrate disposed near an electron gun having a plurality of electrodes arranged thereon, a resistance material formed on the insulation substrate in a predetermined pattern, and an insulation material formed on the resistance material. A film; a first large electrode lead-out portion provided at one end of the resistor material and to which a high voltage is applied; a second large electrode lead-out portion provided in the middle of the resistor material to take out a predetermined potential; and the resistor material. A third large electrode lead-out portion provided on the other end of the electron gun, and a connector is brought into contact with the large electrode lead-out portion to form an electric circuit, thereby giving a predetermined division potential to a predetermined electrode of the electron gun. In the resistor with a built-in cathode ray tube, the third large electrode lead-out portion has at least two small electrode lead-out portions including a small electrode lead-out portion located at the end of the resistance material, and one end thereof is the end. Connected to the small electrode extraction part located at There comprising a connecting member connected to the other small electrode lead-out portion, the cathode ray tube internal resistor and adjusts the division potential of the second large electrode lead-out portion by a connection position of the connecting member.