JPH06325910A - Variable resistor for high voltage - Google Patents

Abstract

PURPOSE:To decrease the soldered places of lead terminals and the like on an insulating substrate or to contrive to completely eliminate the soldered parts in a variable resistor for high voltage, which is formed by providing first and second output terminal electrodes on the end surface on the side of the same short side of the reactangular insulating substrate. CONSTITUTION:In the surface of a rectangular insulating substrate 22, at least a first output terminal electrode 25 and a second output terminal electrode 26 are formed of a cermet resistance material having a sheet resistivity lower than that of a first film resistor 28 having a first variable resistance part 28a and a second variable resistance part 28b. The electrode 26 and a second center electrode 30 on the side of the part 28b are connected to each other through a third film resistor 53 formed along the end surface on the side of the long side of the substrate 22 and at the same time, this resistor 53 is formed of a cermet resistance material having a sheet resistivity lower than the of the resistor 28, conductive rubbers are respectively arranged on at least the electrodes 25 and 26 and lead terminals are respectively connected to these conductive rubbers.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high voltage variable resistor, and more particularly to a high voltage variable resistor suitable for supplying a high voltage to a focus electrode and a screen electrode of a cathode ray tube of a television receiver or the like. Regarding vessels.

[0002]

2. Description of the Related Art Conventionally, this type of high-voltage variable resistor is
For example, it is configured as shown in FIGS. 4 and 5. FIG. 4 is a longitudinal sectional view of a main part of the high voltage variable resistor, and FIG. 5 is a plan view of an insulating substrate that constitutes the high voltage variable resistor.

That is, a rectangular insulating substrate 22 made of ceramic such as alumina is attached to an inner wall surface step portion 21 of an insulating case 20 which is made of resin and has a bottom wall portion 20a and a side wall portion 20b and which has an opening on one side. It is fixed by etc.
On the surface of the insulating substrate 22, the input terminal electrode 23, the ground terminal electrode 24, the first output terminal electrode 25, the second
The output terminal electrode 26 and the relay terminal electrode 27 are formed. Of these terminal electrodes, the first output terminal electrode 25 and the second output terminal electrode 26 are the insulating substrate 2
2 is disposed at a predetermined distance along one end surface of the short side, and the grounding terminal electrode 24 and the relay terminal electrode 27 are disposed along the other end surface of the insulating substrate 22 at a predetermined interval. It is arranged. The input terminal electrode 23 is arranged between the grounding terminal electrode 24 and the first output terminal electrode 25. That is, in this embodiment, the input terminal electrode 23, the ground terminal electrode 24, and the first output terminal electrode 25 are arranged at predetermined intervals along one long-side end surface of the insulating substrate 22. ing.

Further, a first film resistor 28 connected to the input terminal electrode 23 and the grounding terminal electrode 24 is formed on the surface of the insulating substrate 22. The first film resistor 28 includes an arc-shaped first variable resistance portion 28a near the input terminal electrode 23 and an arc-shaped second variable resistance portion 28b near the ground terminal electrode 24. have.
A first center electrode 29 is formed in the center of a region surrounded by the first variable resistance portion 28a on the surface of the insulating substrate 22.
A second center electrode 30 is formed in the center of the region surrounded by the variable resistance portion 28b.

On the surface of the insulating substrate 22, the second film resistor 3 is connected to the first output terminal electrode 25 and the first center electrode 29 and covers the first center electrode 29.
1, the relay terminal electrode 27 and the second center electrode 3 are formed.
The film conductor 32 is formed by being connected to 0. Further, a third film resistor 33 is formed so as to cover the second center electrode 30 and the film conductor 32.

Further, at both end positions of the first variable resistor portion 28a and the second variable resistor portion 28b of the first film resistor 28 (positions which are the start point and the end point of the rotation range of the slider described later). The reference point electrodes 34, 35, 36 and 37 are formed between the insulating substrate 22 and the first film resistor 28, respectively.

The above-mentioned terminal electrodes 23, 24, 25, 2
6, 27, the center electrodes 29, 30, the film conductor 32, and the reference point electrodes 34, 35, 36, 37 are made of Ag-based conductive materials such as Ag and Ag-Pd, and the film resistors 2 are formed.
8, 31, 33 are made of the same cermet resistance material.

On the back surface of the insulating substrate 22, a lead wire 38 for connecting the second output terminal electrode 26 and the relay terminal electrode 27 on the surface of the insulating substrate 22 is provided on the other long side end surface of the insulating substrate 22. Both ends are inserted into through holes formed in the terminal electrodes 26, 27 of the insulating substrate 22 and soldered to the terminal electrodes 26, 27.

For the input terminal electrode 23 and the grounding terminal electrode 24, the lead terminal 3 is formed in the through hole formed in the terminal electrode portion of the insulating substrate 22 from the back side of the insulating substrate 22.
9 and 40 are inserted and soldered to the terminal electrodes 23 and 24, respectively. The lead terminal 40 is bent in the middle and drawn out from the side wall portion 20b of the insulating case 20 to the outside of the case.

In the first output terminal electrode 25 and the second output terminal electrode 26, the relay terminal 41 (from the surface side of the insulating substrate 22 to the through hole formed in the terminal electrode portion of the insulating substrate 22). (Only one shown) is inserted into each terminal electrode 2
Soldered to 5,26. This relay terminal 41 is
It is formed by pressing a metal plate, and has a pair of sandwiching pieces 41a and 41b in the center. Then, a lead terminal 42 (only one of which is shown) inserted between the pair of holding pieces 41a and 41b from the outside of the insulating case 20 via the side wall portion 20b is attached to the relay terminal 41 so as to be held between the pair of holding pieces 41a and 41b. . An insulating sleeve 43 (only one is shown) integrally formed with the insulating case 20 is provided around the lead terminals 42.

The insulating case 20 has a bottom wall portion 20a bearing a first rotating shaft 44 and a second rotating shaft 45, and is positioned inside the insulating case 20 integrally formed with the rotating shafts 44 and 45. Sliders 46 and 47 are attached to the flange portions 44a and 45a, respectively. These sliders 4
Reference numerals 6 and 47 denote center electrodes 29 and 30 on the surface of the insulating substrate 22.
Centering on each of the variable resistance portions 2 of the first film resistor 28.
8a, 28b on the reference point electrodes 34, 35 and 36,
Each slides between 37.

A rib 48 for preventing discharge is formed on the bottom wall portion 20a of the insulating case 20 if necessary.
The back surface of the insulating substrate 22 is filled with resin 49. When the discharge preventing ribs 48 are formed, the insulating substrate 22 is adhered to the discharge preventing ribs 48 with an adhesive.

The high-voltage variable resistor configured as described above is used, for example, integrally with a flyback transformer, the input terminal electrode 23 side is connected to the high-voltage output of the flyback transformer, and the ground terminal is used. The electrode 24 side is connected to the reference potential. Then, the first variable resistance portion 28a
Side, that is, the first output terminal electrode 25 side, the first output (focus voltage) is output via the side wall portion 20b of the insulating case 20, and the second variable resistance portion 28b side, that is, the second output side. Insulation case 20 from the output terminal electrode 26 side
Second output (screen voltage) through the side wall 20b of the
Is output.

In the variable resistor for high voltage described above, the lead terminal 42 connected to the relay terminal 41 is not provided on the manufacturer side of the variable resistor for high voltage, but the variable resistor for high voltage is replaced by the flyback transformer. In some cases, the lead terminal made of a high-voltage lead wire or the like is attached to the relay terminal 41 on the user side after attachment to the relay terminal 41.

[0015]

As described above, in the conventional high voltage variable resistor, the lead terminals 39 and 4 are used.
0 and the relay terminal 41 are attached to a predetermined terminal electrode by soldering. Since this soldering is usually performed manually using a soldering iron, there is a problem that if there are many soldering points, the soldering work becomes complicated accordingly.

Further, in order to obtain the output from the second variable resistance portion 28b side from the second output terminal electrode 26 side, the lead wire 38 is arranged on the back surface side of the insulating substrate 22, and both ends thereof are arranged. Second output terminal electrode 26 and relay terminal electrode 2
Must be soldered to 7. This soldering is usually
Since the soldering iron is used as in the above case, there is a problem that the number of soldering points is further increased and the soldering work is further complicated.

Accordingly, it is an object of the present invention to provide a high voltage variable resistor which can reduce the number of soldering points such as lead terminals or eliminate the soldering points such as lead terminals altogether. .

[0018]

To achieve the above object, in a high voltage variable resistor according to claim 1 of the present invention, at least a first output terminal electrode and a second output terminal are provided. The electrode is formed of a cermet resistance material having a lower sheet resistance than the first film resistor having the first variable resistance portion and the second variable resistance portion, and the second output terminal electrode and the second variable resistance are provided. The second center electrode on the side of the insulating film is connected by a third film resistor formed on the surface of the insulating substrate along the end face on the long side thereof, and the third film resistor is connected to the first film resistor. It is characterized in that it is formed of a cermet resistance material having a lower sheet resistance than the body, and conductive rubber is arranged on at least the first output terminal electrode and the second output terminal electrode.

Further, a high voltage variable resistor according to a second aspect of the present invention is characterized in that a lead terminal is connected to the conductive rubber of the high voltage variable resistor according to the first aspect.

[0020]

According to the present invention, at least the first output terminal electrode and the second output terminal electrode among the respective terminal electrodes are formed of a cermet resistance material having a lower sheet resistance than the first film resistor. Therefore, not only does it function as a terminal electrode similar to the case of the conventional Ag-based conductive material, but the surface is oxidized like a conventional Ag-based conductive material even when exposed to air for a long period of time. Never be done. Therefore, good electrical contact with the conductive rubber is maintained for a long period of time. Since the lead terminal is inserted or contacted with this conductive rubber on the manufacturer side or the user side of the high-voltage variable resistor, the number of soldering points of the lead terminal can be reduced or completely eliminated. It becomes possible.

In order to obtain the output from the second variable resistance portion side from the second output terminal electrode side, the second center electrode and the second output terminal electrode are connected by the third film resistor. Therefore, it is not necessary to solder even in this portion, and when assembling the high-voltage variable resistor, the number of soldering points can be reduced or eliminated altogether.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a main part of a high voltage variable resistor according to the present invention, and FIG. 2 is a plan view of an insulating substrate constituting the high voltage variable resistor. By using the same reference numerals for the same or similar members as those in the conventional example in these drawings, detailed description thereof will be omitted, and the differences from the conventional example will be mainly described below.

That is, inside the insulating case 20, the input terminal electrode 23, the grounding terminal electrode 24, the first output terminal electrode 25, and the second output terminal electrode 26 formed on the surface of the insulating substrate 22. At the position corresponding to
Cylindrical conductive rubber storage parts 50, 51, 52 (conductive rubber storage parts corresponding to the second output terminal electrodes 26 are not shown) are formed to store conductive rubber described later.

Each terminal electrode 23, 2 on the surface of the insulating substrate 22
4, 25 and 26 are, for example, 10Ω / □ to 100KΩ
A resistance paste made of a cermet resistance material such as ruthenium oxide having an area resistance of about / □ lower than that of the first film resistor 28 is printed and fired.
This sheet resistance indicates the resistance value between both ends of the square shaped film resistor.

On the other hand, the first film resistor 28 connected to the input terminal electrode 23 and the grounding terminal electrode 24.
Is formed by printing and firing a resistance paste made of a cermet resistance material such as ruthenium oxide having a sheet resistance of about 1 MΩ / □ to 10 MΩ / □.

First center electrode 29 and second center electrode 30
Is formed by printing and firing a resistance paste made of a cermet resistance material having the same low sheet resistance as the terminal electrodes 23, 24, 25 and 26. The second film resistor 31 connected to the first output terminal electrode 25 and the first center electrode 29 is printed with a resistance paste made of a cermet resistor material having the same sheet resistance as the first film resistor 28. It is then fired and formed. The third film resistor 53 is connected to the second output terminal electrode 26 and the second center electrode 30.
Are formed. The third film resistor 53 is disposed on the surface of the insulating substrate 22 and along the end face on the long side of the insulating substrate 22, and has the same low cermet resistance as the terminal electrodes 23, 24, 25, 26. A resistance paste made of a resistance material is printed and fired. That is, in this embodiment, the second output terminal electrode 26, the second
Since the center electrode 30 and the third film resistor 53 of 5 are made of the same material, they are all formed at the same time.

The intermediate portion of the third film resistor 53 may be cut off, and this portion may be connected with an Ag-based conductive material. In addition, because the third film resistor 53 is provided along the end face of the insulating substrate 22 on the long side,
In the film resistor 28, the high potential side of the first variable resistor portion 28a is displaced from the second variable resistor portion 28b side to the longer side of the opposite side where the input terminal electrode 23 and the like are formed. Are provided. However, if there is no problem in terms of withstand voltage characteristics, it is not always necessary to adopt this embodiment.

The reference point electrodes 34, 35, 36, 37 provided on the first variable resistance portion 28a and the second variable resistance portion 28b of the first film resistor 28 are the terminal electrodes 23, 2 respectively.
A resistance paste made of a cermet resistance material having the same low sheet resistance as 4, 25 and 26 is printed and fired.

According to this embodiment, each terminal electrode and each film resistor on the surface of the insulating substrate 22 are made of two types of cermet resistance materials having different sheet resistances.
Two prints and one or two firings will suffice. However, it is not always necessary to use two types of cermet resistance materials, and three or more types may be used.

Further, each terminal electrode 23, 24, 25, 26
The conductive rubbers 54, 55, 56 (the conductive rubber corresponding to the second output terminal electrode 26 is not shown) are arranged in contact with the. These conductive rubbers 54, 55, 56 are
Conductive rubber storage parts 50, 51, 52 in the insulating case 20
When the insulating substrate 22 is arranged inside and fixed to the inner wall surface step portion 21 by adhering it with an adhesive or the like, each electrode 23, 24, 2
5, 26 are in elastic contact with each other.

The conductive rubbers 54 and 55 arranged on the input terminal 23 and the grounding terminal electrode 24 are attached to the insulating substrate 22.
Of the lead terminal 3 from the rear surface side of the insulating substrate 22 through the through holes formed in the corresponding terminal electrodes 23, 24 of the
9 and 40 are inserted. Of these, the lead terminal 40
Is bent in the middle and is bent to a side wall portion 20b of the insulating case 20.
It is pulled out from the side to the outside of the case.

The conductive rubber 56 (the conductive rubber on the second output terminal electrode 26 is not shown) is disposed on the first output terminal electrode 25 and the second output terminal electrode 26. Lead terminals 42 (lead terminals corresponding to the second output terminal electrodes 26 are not shown) inserted from the outside of the insulating case 20 through the side wall portions 20b are inserted. Each of these lead terminals is not limited to a plate-shaped or pin-shaped one, and may be a lead wire with an insulating coating. The lead terminal inserted through the side wall portion 20b of the insulating case 20 is not inserted on the manufacturer side of the high voltage variable resistor, but after it is mounted on the flyback transformer or the like on the user side. Good. Further, each lead terminal and each conductive rubber are connected by contacting the lead terminal with the surface of the conductive rubber instead of connecting the lead terminal by inserting the lead terminal into the conductive rubber as in the above embodiment. You may When the lead terminal is brought into contact with the surface of the conductive rubber as described above, the lead terminal 42 and the like may be provided on the side wall portion 20b of the insulating case 20 in advance.

In the above embodiment, the conductive rubber is used for each terminal electrode 23, 24, 25, 26,
In such a case, the soldering of the lead terminals can be completely eliminated, and as a result, the cleaning for removing the flux becomes unnecessary. Cleaning to remove flux is
Usually, trichlene, chlorofluorocarbon, etc. are used, but if such cleaning is not necessary, it can also contribute to the prevention of environmental damage to the earth.

However, in the present invention, it is not always necessary to use conductive rubber for all the terminal electrodes. At least the first output terminal electrode 25
It may be used only for the second output terminal electrode 26. In that case, the terminal electrode not using the conductive rubber is made of the same Ag-based conductive material as the conventional one, and the lead terminal is soldered. Even in that case, the number of soldering points can be reduced and the soldering work can be simplified.

The lead terminal inserted through the side wall portion 20b of the insulating case 20 is not directly inserted into the conductive rubber as in this embodiment, but is connected to the first output terminal electrode 25. As shown in FIG. 3 showing only the corresponding side, the relay terminal 41 similar to the conventional one may be inserted into the conductive rubber 56, and the lead terminal 42 may be inserted between the sandwiching pieces 41a and 41b of the relay terminal 41. In such a case, the relay terminal 41 and the lead terminal 42 are collectively referred to as a lead terminal. The same applies to the lead terminal corresponding to the second output terminal electrode 26 (not shown).

In the above embodiment, each center electrode 2
9, 30 and each of the reference point electrodes 34, 35, 36, 37 are made of a cermet resistance material, and in this case, the rotation life characteristics and the pulse resistance characteristics are excellent,
These can also be formed of the same Ag-based conductive material as in the past. Alternatively, the first center electrode 29 may be removed so that the second film resistor 31 covering it may serve as the center electrode. Alternatively, the first center of the second film resistor 31 may be removed. The electrode 29 portion may be removed so that the first center electrode 29 made of a cermet material having a low sheet resistance is exposed. Furthermore, each reference point electrode 34, 35, 3
Although 6, 37 are formed on the lower side of the first film resistor 28, they may be formed on the upper side thereof. Further, the portion of the first film resistor 28 where the reference point electrodes 34, 35, 36, 37 are located is cut off, and the reference point electrodes 34, 35,
The first film resistor 28 may be in a continuous state via 36 and 37.

[0038]

As is apparent from the above description,
According to claims 1 and 2 of the present invention, at least the first output terminal electrode and the second output terminal electrode are formed of a cermet resistance material having a lower sheet resistance than the first film resistor, Since the lead terminals are connected to the conductive rubber placed on the terminal electrodes, it is possible to reduce the soldering points on the lead terminals or to eliminate the soldering points altogether, and it is said that the assembly workability is excellent. Become.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of a main part of a high voltage variable resistor according to an embodiment of the present invention.

FIG. 2 is a plan view of an insulating substrate used in the high voltage variable resistor of the present invention.

FIG. 3 is a partial cross-sectional view of a high voltage variable resistor according to another embodiment of the present invention.

FIG. 4 is a longitudinal sectional view of a main part of a conventional high voltage variable resistor.

FIG. 5 is a plan view of an insulating substrate used in a conventional high voltage variable resistor.

[Explanation of symbols]

 20 Insulating Case 21 Inner Wall Step 22 Insulating Substrate 23 Input Terminal Electrode 24 Ground Terminal Electrode 25 First Output Terminal Electrode 26 Second Output Terminal Electrode 28 First Film Resistor 29 First Central Electrode 30 2nd center electrode 31 2nd film resistor 34, 35, 36, 37 Reference point electrode 39, 40, 42 Lead terminal 41 Relay terminal 43 Insulation sleeve 44, 45 Rotating shaft 46, 47 Slider 48 Discharge prevention Ribs 49 Resin 50, 51, 52 Conductive rubber housing 53 Third film resistor 54, 55, 56 Conductive rubber

Claims (2)

[Claims] 1. A rectangular insulating substrate is housed in a one-sided opening-shaped insulating case having a bottom wall portion and a side wall portion, and a first rotating shaft and a second rotating shaft are provided on the bottom wall portion of the insulating case. And a first output and a second output from the same side wall portion of the insulating case of the variable resistor for high voltage, wherein the input terminal electrode and the ground are provided on the insulating substrate surface. A circle on the side close to the input terminal electrode, the first output terminal electrode, the second output terminal electrode, the input terminal electrode and the grounding terminal electrode. The arc-shaped first variable resistance portion and the arc-shaped second variable resistance portion on the side close to the ground terminal electrode.
A first film resistor having a variable resistance part of
A first center electrode located in a region surrounded by the variable resistance part, a second center electrode located in a region surrounded by the second variable resistance part, and the first output terminal electrode A second film resistor for connecting the first center electrode and a third film resistor for connecting the second output terminal electrode and the second center electrode are provided, and the first film resistor for the first output is provided. The terminal electrode and the second output terminal electrode are arranged along the same short side end surface of the insulating substrate at a predetermined interval, and the third film resistor is arranged along the long side end surface of the insulating substrate. Then, in the insulating case, the first
And a second slider attached to the rotating shaft of the first rotating body and sliding on the first variable resistance portion around the first center electrode, and attached to the second rotating shaft and having the second center. A second slider that slides on the second variable resistance portion centering on the electrode, and the first film resistor is formed of a cermet resistance material,
At least the first output terminal electrode, the second output terminal electrode, and the third film resistor are formed of a cermet resistance material having a lower sheet resistance than the first film resistor, and at least the first film resistor is formed. 2. A variable resistor for high voltage, characterized in that conductive rubber is arranged on the output terminal electrode and the second output terminal electrode. 2. The variable resistor for high voltage according to claim 1, wherein a lead terminal is connected to the conductive rubber.