JPS60124339A - Resistor built in cathode ray tube - Google Patents

Abstract

PURPOSE:To avoid accidents during a knocking disposition process and improve the coefficient of utilization of the area of an insulated base plate by selecting a proper one of the turn back positions on the zig-zag pattern of a voltage-dividing resistor layer formed on the insulated base plate. CONSTITUTION:Each turn-back position 19e on the zig-zag pattern of a voltage- dividing resistor layer 19 formed on an insulated base plate 18 is selected so that the minimum distance Lm from it to the outer surface 20a of an insulated coating 20 will be as short as possible and have a sufficient length to prevent changes in the resistance value of the voltage-dividing resistor layer 19 due to the insulated coating 20 being broken by a large potential difference which is caused by a high voltage applied during a cathode ray tube knocking disposition process. In this way, no changes are caused to the resistance value even in the cathode ray tube knocking disposition process, and moreover the voltage-dividing resistor layer 19 having a large effective length can be obtained because the surface area of the insulated base plate is used effectively.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a built-in resistor that is incorporated together with an electron gun in a tube such as a color cathode ray tube.

BACKGROUND ART AND PROBLEMS Conventionally, some color cathode ray tubes and the like used in color television receivers require high voltages to be supplied to convergence electrodes, focus electrodes, etc. in addition to the anode voltage. In such a case, it has been proposed to incorporate a resistor for voltage division into the tube together with the electron gun as a built-in resistor, thereby dividing the anode voltage to obtain high voltages.

An example of a color cathode ray tube incorporating such a built-in resistor is shown in FIG. Reference numeral 1 denotes a tube body, and an electron gun structure 2 is disposed within the neck portion la of the tube body 1. This electron gun structure 2 has a first grid electrode Gl, a common electrode for three cathodes K, Second grid electrode G2. Third grid electrode G3. A fourth grid electrode G4 and a fifth grid electrode G5 are sequentially arranged coaxially. A convergence means 3 is arranged after the fifth grid electrode G5. Each grid electrode G1, G2.
G3. G4 and G5 and the convergence means 3 are mechanically connected by beading glass 4 while maintaining a predetermined positional relationship with each other, and the third grid electrode G3
and the fifth grid electrode G5 are electrically connected by a conductive wire 5. Further, the convergence means 3 is
Inner deflection electrode plates 3a and 3b facing each other and electrically connected to the fifth grid electrode G5 via the conductive plate 6, and an outer deflection electrode disposed on the outside facing the inner deflection electrode plates 3a and 3b. It is formed with electrode plates 3c and 3d.

A built-in resistor 7 is attached to such an electron gun structure 2, and a high-voltage electrode terminal 8 installed on the built-in resistor 7 is conductively attached to the fifth grid electrode G5.
convergence electrode terminal (hereinafter referred to as
A conductive number (referred to as a CV electrode terminal) 10 is connected to the outer deflection electrode plates 3c and 3d of the convergence means 3 via a J barb 11, and a ground electrode terminal] 2 is connected to the neck portion 1a of the tube body 1. The conductive attachment is connected via a piece 15 to an earth electrode terminal pin 14 embedded through the stem 13 at the base of the holder.

Furthermore, a graphite i-electric film 16 extending to the inner wall of the neck portion 1a is adhered to the inner wall of the funnel portion 1b of the tube body 1, and a high-pressure supply button, that is, an anode button ( An anode voltage is supplied through the terminal (not shown). A conductive spring 17 is provided on the conductive plate 6, and when the conductive spring 17 comes into contact with the graphite conductive film 16, the fifth grid electrode G5. Third grid electrode G3. An anode voltage is supplied to the inner deflection electrode plates 3a and 3b of the convergence means 3 and the high voltage electrode terminal 8 of the built-in resistor 7.

Built-in resistor 7 built into such a color cathode ray tube
is assumed to have a configuration as shown in FIGS. 2 to 4. FIG. 2 shows the built-in resistor 7 seen through from above the insulating coating forming the outer surface, and FIGS. 3 and 4 show the built-in resistor 7 shown in FIG.
A cross section along the line and a cross section along the TV-TV line are shown. In the conventional built-in resistor 7 shown in FIGS. 2 to 4, a terminal portion formed by depositing a conductive layer on an insulating substrate 18 such as a ceramic plate, that is, an anode voltage is supplied. High voltage electrode terminal 8. A CV electrode terminal 10 and a ground electrode terminal 12 are provided to obtain a high voltage for the convergence electrode, that is, a convergence voltage.
Between the CV electrode terminal 10 and the earth electrode end -r-12, a resistor layer 19a having a jig-shaped pattern having a predetermined resistance value is connected to the high voltage electrode terminal 8 and the CV electrode terminal 10.
zigzag shape with the same predetermined resistance value between
Further, fine adjustment resistor layers 19C are deposited between the resistor layers 19a and 191] and the CV electrode terminal 10, respectively.
9 is formed. An insulating film 20 made of lead glass or the like is provided on the shaded area in FIG. 2, covering the voltage dividing resistor layer 19. In addition, fine adjustment resistor layer 1
9c is provided so that the resistance value of the resistor layers 19a and 1.9b between each terminal can be adjusted by removing a part of it in the manufacturing process of the built-in resistor 7. Ru.

When the built-in resistor 7 configured as described above is installed together with the electron gun assembly 2 in the above-mentioned ray tube, the anode voltage supplied to the high voltage electrode terminal 8 is applied to the CV electrode terminal 10 at a resistance. A convergence voltage is obtained by dividing the voltage between the body layers 19a and 19b, and this convergence voltage is supplied to the outer deflection electrode plates 3C and 3d. Further, the earth electrode terminal 12 is passed through the earth electrode terminal pin 14 of the tube body 1 and is normally grounded via an external variable resistor for adjustment.

In such a built-in resistor 7, the CV electrode terminal 10 is required to supply a constant convergence voltage to the outer deflection electrode plates 3c and 3d of the convergence means 3, and fine adjustment of this convergence voltage is performed by the tube body 1. This is done using an external adjustable variable resistor inserted between the earth electrode terminal pin 14 and the ground. For this reason, those with a narrow variable range are used. For this reason, in order to enable adjustment in a narrow variable range of the variable resistance layer, the resistor layers 11 (of the resistor layers forming the voltage dividing resistor layer 19 of the built-in resistor 7) 9a and 19b are In order to keep the resistance as constant as possible, adjustment is performed using the above-mentioned fine adjustment resistor layer 19c.

By the way, in the first generation resistor 7, the voltage dividing resistor layer 19 is formed into a zigzag pattern by utilizing the board surface of the insulation board IB as effectively as possible, especially the resistor layer t9a has a large effective effect. In order to obtain a long
It is desired that the meandering width W be made larger than the position near the edge portion I8a of No.8. However, if each folded end 19e of the zigzag pattern of the resistor layer 19a is located extremely close to the edge 18a of the insulating cutting board 18, problems as described below will occur.

When the built-in layer 11 (antilayer 7) is installed and used in a cathode ray tube as shown in FIG. Then, the resistor layer 1
A potential difference is generated between the potential at each part of 9a and the potential on the outer surface of the insulating coating 2o, and this potential difference is applied to the insulating coating 2o. The thickness of the insulating coating 2o is selected so that it can withstand such a potential difference.
In the cross section in the meandering width direction of a, as shown in FIG. It gradually becomes thinner. This naturally occurs because the insulating film 2o is formed by drying and baking a fluid insulating material that is coated on the insulating substrate 18 to cover the resistor layer 19a. That's true. Therefore, the position near the cut/notch part 18a of the insulation cutting board 18 is insulated at n@20.
This is the part where the thickness is small and the withstand voltage characteristics are reduced. When the folded end portion 19e of the zigzag pattern of the resistor layer 19a is arranged at such a position, the potential difference between the folded end portion 19e and the outer surface of the insulating coating 20 is reduced due to the small thickness. If the withstand voltage limit of the insulating wave film 20 is exceeded, the insulating coating 20 may undergo dielectric breakdown, and as a result, the resistance value of the resistor layer 19a may change significantly. In particular, people are at risk of such inconveniences occurring during the knocking process in the manufacturing process of cathode ray tubes.

For example, in a cathode ray tube equipped with a built-in resistor 7 shown in FIG. 1, if there are sharp protrusions on various parts of the electron gun structure 2, undesired discharge will occur during actual use. Therefore, in the manufacturing process, parts of the electron gun assembly 2 that are likely to generate electric discharge, such as sharp protrusions, are melted and molded after generating electric discharge in advance, so that the parts that are likely to generate electric discharge, such as sharp protrusions, can be melted and molded. Knocking treatment is performed with the primary purpose of stabilizing the operation. In such a knocking treatment process, for example, a high voltage (knocking voltage) that is 2 to 3 times higher than when the cathode ray tube is in actual operation is applied. is applied to the third grid electrode G3, the fifth grid electrode G5, and the high voltage electrode terminal 8 of the built-in resistor 7, and is applied to each of the first, second, and fourth grid electrodes Gl, G2, and G.
4 is considered to be in a grounded state. Furthermore, the ground electrode terminal 12 of the built-in resistor 7 is grounded via an external variable resistor for adjustment. During this knocking process, the outer surface of the insulating coating 20 of the built-in resistor 7 is charged to a high potential according to the knocking voltage, and the insulating coating 20 is temporarily charged with a voltage on the low voltage side of the resistor layer 19a compared to when it is in actual operation. Therefore, a large potential difference will be applied. For example, the third grid electrode G3 to which a high voltage is applied
The potential difference between the resistor layer 19a and the surface of the insulating coating 2o becomes particularly large at a portion of the resistor layer 19a that has a relatively low potential at a position close to the insulating coating P. ;! 20 will be subject to a large potential difference. Therefore, each folded end 19e of the zigzag pattern of the resistor layer 19a of the built-in resistor 7 is connected to the insulating substrate 18.
In the vicinity of the edge portion 18a of the insulating substrate 18 in the vicinity of the third grid electrode G3, a potential difference that exceeds the withstand voltage is applied to the insulating coating 20, causing the insulating coating 20 to become disconnected! (A situation that causes destruction of the coating 20 easily occurs, and the 11(jjL body layer 19a... is damaged and its 11°C resistance value changes abruptly.)Then, the resistance of the built-in resistor 7 If the resistance value of the body layer 19a changes, it becomes impossible to obtain a predetermined convergence voltage at the C2 electrode terminal 10.

Therefore, in the conventional built-in resistor 7, the insulating substrate 1
Each folded end 19e of the zigzag pattern of the voltage dividing resistor layer 19 on the top 8 is designed to be more secure than necessary so that the insulating coating 20 will not be destroyed even during knocking treatment of the cathode ray tube, which has been obtained from experience. It is placed sufficiently away from the expected edge portion 182 of the insulating substrate 18, and as a result, the plate surface of the insulating substrate 18 cannot be used effectively.

Purpose of the Invention In view of the above, the present invention provides a method for attaching a cathode ray tube to a cathode ray tube by appropriately selecting the position of each folded end of a zigzag pattern of a voltage dividing resistor layer formed on an insulating substrate. Even when faced with the non-king treatment process for cathode ray tubes,
Accidents in which the resistance value of the voltage-dividing resistor layer is significantly changed or tightened can be avoided, and the utilization rate of the board surface of the insulating substrate is improved, making it possible to make the effective length of the voltage-dividing resistor layer sufficiently large. The purpose of the present invention is to provide a built-in resistor for a cathode ray tube.

Summary of the Invention A built-in resistor for a cathode ray tube according to the present invention includes a plurality of electrode terminals and a resistor layer arranged in a zigzag pattern between the electrode terminals on an insulating substrate made of ceramic or the like. Further, an insulating film covering the resistor layer is provided, and the position of each folded end of the zigzag pattern of the resistor layer is such that the shortest distance to the outer surface of the insulating film disposed thereon is: The length is selected to have a length necessary to prevent a change in the resistance value of the resistor layer due to the high voltage applied in the non-king process of the cathode ray tube, and to be as short as possible. With this configuration, the position of each folded end of the zigzag pattern of the resistor layer is >th Lm 45 +Fi within a range that does not cause damage due to voltage application exceeding the withstand voltage limit of the insulating film.
The surface of the insulating substrate is effectively utilized.

Example Examples of the present invention will be described in detail below.

An example of the built-in fLE resistance layer 7 according to the present invention has the same configuration and external shape as the built-in resistor 7 shown in FIGS. The position of each folded end 19e of the zigzag pattern of the body layer 19 is determined by the shortest distance from the outer surface 20a of the insulating coating 20, which is represented by Lm in the enlarged cross section shown in FIG. It has a length necessary to prevent the insulating film 20 from being destroyed by a large potential difference caused by a high voltage applied in the voltage dividing resistor layer 19, and a change in resistance I1 of the voltage dividing resistor layer 19. The results are selected to be as short as possible.

The selection of the position of the folded end portion 19e of the zigzag pattern of the voltage dividing resistor layer 19 as described above will be described below.

The insulating coating 20 of the built-in resistor 7 as shown in FIGS. 2 to 4H has a thickness t on the insulating substrate 18 as shown in FIG.
Except for the area near a, the thickness T is within the size range necessary to prevent dielectric breakdown under various conditions including the conditions during non-king treatment of cathode ray tubes and is as small as possible. It is assumed that the thickness T is set as follows, and such a thickness T is obtained at least in the central portion in the width direction of the insulating substrate. Therefore, the shortest distance Lm" to the outer surface 20a of the insulating coating 20 on the insulating substrate 18 is Thickness T of the insulating coating 20 at the central portion in the width direction of the substrate 18 (hereinafter simply 17
(referred to as Tc).

The inventor of the present application set the width, that is, the dimension in the direction of the meandering width W of the voltage dividing resistor layer 19, to be 9.6 mm as the built-in resistor 7 having the configuration shown in FIGS. 2 to 4. The insulating coating 20 is formed on the insulating plate 1'8, and the insulating coating 20 covering the partial voltage resistor layer 19 has a thickness Tc of 0.
3mm, 0.5mm, 0.6mm and 1. Om
m, and the thickness t of the insulating coating 20 at each part on the insulating substrate 18 was measured for each of them. Figure 6 shows the relationship between the distance X from the edge measured toward the center (vertical axis is t (mm)
The experimental results are obtained as shown in (the horizontal axis is x (mm)). In FIG. 6, curves A, B, C, and D have thickness Tc of 0.3 mm and 0.5 mm, respectively.
, indicates the thickness t of the insulating coating 20 in the case of 0.6 mm and 1.0 mm, and therefore indicates the position of the outer surface 20a of the insulating coating 20 on the insulating substrate 18. From this result, the position P where the shortest distance L m I to the outer surface 20a of the insulating coating 20 on the insulating substrate 18 is equal to the thickness Tc
a (for Tc-0.3mm), Pb (Tc
= 0.5mm), Pc (Tc-Oz6m
The distances from the edge of Pd (for Tc = 1.0 mm) and Pd (for Tc = 1.0 mm) are 0.7 mm and 1.3 mm, respectively.
, 1.5 mm and 2.0 mm, and the position where the thickness Tc as shown in FIG. 7 and the shortest distance Lm' between the outer surface 20a of the insulating coating 20 on the insulating substrate 18 are equal to 17 mm Tc. The relationship with the distance Lx from the edge is obtained.

If the relationship shown in FIG. 7 is expressed in semi-logarithmic coordinates with the vertical axis on a logarithmic scale, it will be approximated by a straight line IE as shown in FIG. Then, when the approximate expression representing the straight line E in Fig. 8 is calculated by the least squares method, log Tc=0.4009 ・Lx−0,8127・
...(1) was obtained. That is, the distance I,
approximately satisfies the relationship of equation (1).

Accordingly, in the example of the built-in resistor according to the present invention, each folded end portion 19e of the zigzag pattern of the voltage dividing resistor layer I9 formed on the insulating substrate 18 is as small as I! ! It is assumed that the distance of Enburi, l 81 from that work, Noji @ B1 a a is arranged at a position that matches Lx that satisfies the above-mentioned formula (1).

As a result of doing this, each folded end portion 19e of the zigzag pattern of the voltage dividing resistor layer 19 has an insulating film temporary 18J.
- ' Shortest distance L to the outer surface 20a of the insulation coating 20
Therefore, the shortest distance to the outer surface 20a of the insulating coating 20 is shortened by the distance G caused by the high voltage applied in the backing process of the cathode ray tube. It has a length necessary to prevent changes in the resistance value of the piezoresistive layer and is as short as possible.

As a result, the resistance value does not change even during the knocking process of the cathode ray tube, and the effective length of the partial voltage resistor is increased by effectively utilizing the plate surface of the insulating substrate 18. It is accompanied by a body layer 19.

Effects of the Invention As is clear from the above explanation, according to the built-in resistor according to the present invention, the insulating coating covering the voltage dividing resistor layer formed in a zigzag pattern on the insulating substrate prevents the knocking of the cathode ray tube. Maximum utilization of the board surface of the insulating substrate while ensuring protection from destruction and changes in resistance due to large potential differences caused by high voltages applied during the processing process. As a result, the meandering width of the zigzag pattern can be expanded and the effective length can be increased. The effective use of the plate surface of the insulating substrate and the increase in the effective length of the voltage dividing resistor layer can alleviate the voltage load per unit length of the voltage dividing resistor layer, and reduce the heating effect on Joule heat in the voltage dividing resistor layer. This brings about benefits such as improved performance.

In addition, since the built-in resistor of the cathode ray tube according to the present invention has extremely small change in the resistance value of the voltage dividing resistor layer, by using this, a relatively high constant voltage within the cathode ray tube is not required. It is possible to stably supply the required constant voltage to the convergence electrode, for example, and further narrow the variable range of the external adjustment variable resistor connected to the outside of the cathode ray tube. As a result, it is possible to improve the accuracy of the external variable resistor for adjustment and reduce power consumption.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram showing the main parts of a cathode ray tube in which a built-in resistor is incorporated, Fig. 2 is a plan view showing details of the built-in resistor incorporated in the cathode ray tube shown in Fig. 1, and Fig. 3. is a sectional view taken along the line I-III in FIG. 2, FIG. 4 is a sectional view taken along the line IV-rl/in FIG. 7 and 8 are diagrams showing experimental results for explaining an example of a built-in resistor of a cathode ray tube according to the present invention. In the figure, 2 is an electron gun assembly, 7 is a built-in resistor, 8 is a high voltage electrode terminal, ] 0 is a convergence electrode terminal, 12 is a ground electrode terminal, 18 is an insulating substrate, 18a is an edge of the insulating substrate 18, and 19 is an Voltage dividing resistor layer 19a is voltage dividing resistor layer 1
9 is a folded end of the zigzag pattern, 20 is an insulating coating, and 20a is an outer surface of the insulating coating 20.

Claims (1)

[Claims] A plurality of electrode terminals and a resistor layer arranged in a zigzag pattern between the electrode terminals are formed on the insulating substrate, and an insulating coating is provided to cover the resistor layer, and the resistor layer The position of each folded end of the zigzag pattern is such that the shortest distance to the outer surface of the insulating film disposed thereon is determined by the high voltage applied in the non-king process of the cathode ray tube. 1. A built-in resistor for a cathode ray tube, which has a length necessary to prevent a change in resistance value of the cathode ray tube, and is selected to be as short as possible.