JPS61147442A - Built-in resistor for cathode-ray tube - Google Patents

Abstract

PURPOSE:To prevent a creeping discharge, make a spark hard to occur, and prevent thermal destruction from occurring by ruggedly forming the surface of an insulating layer. CONSTITUTION:An electrode takeoff section 52a is arranged on a rectangular, thin ceramic substrate 51, next a resistance material 53 is arranged in a zigzag pattern, and this resistance material 53 is coated with an insulating material 54 such as glass. In this case, portions to be protruded are thickly coated. The resistance material is patterned with the electrode takeoff section and resistance material pattern using a mask and is sintered at about 800 deg.C, next it is patterned with a glass material once using a mask, and further the portion to be protruded is patterned with the glass material twice or three times using a different mask, and the glass material is again sintered at about 500 deg.C to form such resistance material. A resistor thus formed is corrugated in its longitudinal direction and is surrounded in the direction perpendicular to the longitudinal direction.

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to the structure of a resistor built into a cathode ray tube.

[Technical background of the invention and its problems]

Generally (in cathode ray tubes such as Yucolor picture tubes, approximately 2
In addition to the high voltage of the anode of 5 to 30, for example, a medium voltage of about 5 to 8 is required for the focusing electrician of an electron gun, and in cases such as mask concentrated color picture tubes, the anode is A high voltage slightly lower than the high voltage is required. Separately supplying such a medium-high voltage other than the anode high voltage from outside the tube has many disadvantages, mainly because the withstand voltage of the supply section becomes large and the structure of the supply section becomes complicated. Therefore, methods of disposing a resistor inside the cathode ray tube and dividing the anode high voltage to obtain the required medium and high voltages are disclosed, for example, in Japanese Utility Model Application No. 48-21561 and No. 55-38484.
No. 3,932,786, and US Pat. No. 4,143,298.

In this case, there is a problem inside the C2 cathode ray tube: When placing a resistor, there is not enough space inside the tube to place a large resistor. . Moreover, this small space forms a fairly complex potential distribution due to the potential of each electrode of the electron gun and the high voltage from the anode from the internal conductive film, and especially (the area near the second internal conductive film is a strong electric field region). Therefore, if a two-handed resistor is placed in such a space, creeping discharge is likely to occur on the surface of the resistor, making it extremely impractical.

Furthermore, when current flows through this resistor, it generates heat, making it more likely to spark, become more susceptible to thermal breakdown, or cause other permanent damage.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a highly reliable resistor for use in a built-in cathode ray tube, which overcomes the above-mentioned conventional drawbacks.

[Summary of the invention]

The present invention provides a resistor for built-in cathode ray tubes, which includes a resistive material having a predetermined length and an insulating layer covering the resistive material, in which the surface of the insulating layer is formed into an uneven shape. This is a resistor for use in cathode ray tubes.

[Embodiments of the invention]

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

FIG. 1 is a perspective view of a resistor implementing the present invention, and FIG.
The figure is a partial cross-sectional view. FIG. 3 is a diagram of an electron gun for a color picture tube using this resistor.

In FIG. 3, the electron gun (1) has a plurality of electrodes, which will be described later, and a plurality of insulating supports 12) that support them.

The plurality of electrodes generate three electron beams (38), (3b), (3C) that strike red, green, and blue phosphors.
three respective heaters (68) for generating.

(6b), (6C-'') are arranged in a row (9a).

(9b) and (9C), predetermined electron beam passage holes are arranged at positions relative to these three cathodes, respectively,
1st grid + with integrated structure (unitized structure)
111. It consists of a second grid a, a third grid αJ, a fourth grid I, and a convergence electrode (151), which are implanted and fixedly supported in this order on the insulating support (2).

The first grid αυ and the second grid are flat electrodes arranged close to each other, and the third grid αJ is the second grid u.
2j l: Consists of two cup-shaped electrodes (231) and (23b) arranged close to each other and connected, and the fourth grid a
4 are two cup-shaped electrodes (248), (2
4b), and the convergence electrode α9 consists of one cup-shaped electrode (251) welded and fixed to the fourth grid. The bottom surface of the cup-shaped electrode and the flat plate electrode of each of the grids and convergence electrodes are provided with three aligned circular electron beam passage holes. A pulp spacer ση is housed in the electrode (15), which applies a high voltage of approximately 25 mm to the anode terminal (not shown) through the internal conductive membrane.Furthermore, a resistor (50) is installed near the electrode. One end of this resistor (50) is connected to a convergence electrode (151), and the other end is externally connected to a variable resistor (49) through a stem pin 4 provided at the bottom of the neck α. The stem pin holder supports and fixes the electron gun, and also allows each grid potential other than the convergence electrode a9 and the fourth grid I to be supplied from the outside through the stem bin α9.

Further, a suitable position of the resistor (50) is in contact with the third grid (1'5).Therefore, the electrical potential (2) is as shown in Fig. 4, and the electrode potential of the third grid 0 is the convergence electrode. (l!19, it is given as a divided potential by the resistor (50) of the high voltage Eb applied to the fourth grid α.

Such an electron gun is enclosed in the neck (18) of a thin glass cylinder, but the space between each electrode and electrode support of the electron gun and the inner wall of the neck is usually only about 1.0 to 1.51111, so This space has a strong field due to the charge on the inner wall of the neck and the potential of each electrode of the electron gun, and when a normal rectangular parallelepiped or cylindrical resistor is inserted into such a space, the surface of the resistor Charges are accumulated and these charges move easily due to the strong electric field, easily causing creeping discharge, making them extremely impractical. Therefore, in the present invention, as shown in FIGS. 1 and 2, the surface of the resistor is formed with a concave and convex groove, which increases the distance on the surface and allows the charge to flow to prevent creeping discharge. . Further, although current flows through the resistor, the surface area of the insulating layer is large, so the temperature of the resistor does not rise due to the heat dissipation effect, and the characteristics are improved.

Such a resistor is manufactured, for example, in the following manner. Second
In the figure, an electrode receiving part (52a) is placed on a rectangular thin ceramic substrate (51), then a resistive material (53) is placed in a zigzag pattern, and an insulating material (such as glass) is placed on top of this resistive material (63). 54). At this time, the portion that will become the protrusion (55) may be coated thickly. The resistive material 63) is preferably made of ruthenium oxide and has a high resistance value of about 500 to 5000 MΩ.
b), (52C) is preferably a resistive material mainly composed of ruthenium oxide, which has a considerably lower resistance than the resistive material (53), or a conductive paint. When using such a resistance material (
Second, a mask is used to pattern the metal electrode extraction part and a resistive material pattern, and the resistive material is sintered at about 800°C.Then, the glass material is patterned once using a mask, and then exposed using another mask. part (=glass material twice, three times)
It is manufactured by buttering the glass material twice and sintering the glass material again at about 500°C.

The resistor produced as described above has a wavy shape in its longitudinal direction (second direction), and the resistor is coiled in a direction perpendicular to the longitudinal direction.

In the above embodiment, the resistor is fixed to the dorsiflexion of the insulating support of the electron gun in contact with the ceramic substrate side, so the above protrusion is not particularly provided on the ceramic cutting board side, but the resistor is When placing the gun on the electrode side, it is better to provide the above-mentioned unevenness on the ceramic substrate side as well.

In the embodiment described above, the resistor is formed on a rectangular thin ceramic substrate, but the present invention is not limited to this, and the resistor material may be spirally coated on an elongated cylindrical ceramic substrate. In this case, the insulating layer is divided into two parts with a concave and convex shape so as to completely surround the resistor.

Further, in the embodiment described above, a resistor was shown that was arranged near the electron gun and supplied the electrode potential of the electron gun as a divided voltage by the resistor, but the present invention is not limited to this.
It can also be applied to the resistor placed near the electron gun for reducing spark current as shown in the specification of No. 345.185, and it can also be applied to the resistor placed in the focus mask tube to supply a mask potential. It can also be applied to resistors.

〔Effect of the invention〕

As described above, in the resistor for built-in cathode ray tubes, creeping discharge can be prevented by forming the surface of the insulating layer in a concave and convex shape, and the resistor is highly reliable, with less sparks and no thermal breakdown. body! It can be realized.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a resistor according to an embodiment of the present invention, and FIG.
Part of the diagram! Cut 78: @ Recovery, Figure 3 is a schematic diagram of an electron gun incorporating the resistor of the present invention, and Figure 4 is an electrical circuit diagram of the resistor. Agent Patent attorney Nori Haruka Chika (and 1 other person) Figure 2 Figure 3

Claims (1)

[Claims] A cathode ray tube built-in resistor comprising a resistive material having a predetermined length and an insulating layer covering the resistive material, wherein the surface of the insulating layer is formed into an uneven shape. Built-in resistor.