JPH11297512A - Variable resistor - Google Patents

Abstract

(57) [Problem] To provide a variable resistor used in general electronic equipment, the output characteristic of which does not become unstable. SOLUTION: An end portion of a resistor 13 of an insulating substrate 11 is formed so as to extend on a base electrode layer 14 and the insulating substrate 11, and a plating layer is formed so as to include the extended portion 15 formed on the resistor 13. Reference numeral 16 is formed on the base electrode layer 14 and the resistor 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable resistor used for general electronic equipment.

[0002]

2. Description of the Related Art As a conventional variable resistor of this kind, there is known a variable resistor disclosed in Japanese Patent Application No. Hei 2-13101 (Japanese Utility Model Application Laid-Open No. Hei 3-104706).

Hereinafter, a conventional variable resistor will be described with reference to the drawings. FIG. 5 is a top view of an insulating substrate in the conventional variable resistor, and FIG. 6 is a side sectional view of the insulating substrate in the variable resistor.

In FIGS. 5 and 6, reference numeral 1 denotes an insulating substrate made of ceramic. The insulating substrate 1 has a hollow hole 2 substantially at the center and a horseshoe-shaped resistor 3 provided on the upper surface. In the vicinity of one side surface of the upper surface of the insulating substrate 1, a base electrode layer 4 containing Ag is provided from the upper surface to the side surface and the lower surface of the insulating substrate 1 so as to be located at both ends of the horseshoe-shaped resistor 3. Provided. And this insulating substrate 1
The end of the resistor 3 is extended on the base electrode layer 4 so that the width is narrower than the base electrode layer 4.
And a plating layer 6 is formed on the extension 5 of the resistor 3 and the upper surface of the base electrode layer 4.

[0005]

However, in the above-described conventional structure, when moisture is added between the insides of the pair of base electrode layers 4, Ag of the base electrode layer 4 migrates, thereby causing There is a problem that the output characteristics of the variable resistor become unstable due to electrical conduction between the pair of base electrode layers 4.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a variable resistor which does not cause unstable output characteristics.

[0007]

In order to achieve the above object, a variable resistor according to the present invention has a hollow hole substantially at the center, a horseshoe-shaped resistor provided on the upper surface, and both ends of the resistor. An insulating substrate having a pair of base electrode layers electrically connected on the upper surface and provided from the side surface to the lower surface and a plating layer provided to cover the base electrode layer,
A driver plate provided with a protruding portion having a through hole protruding toward the insulating substrate and a brush sliding on a resistor of the insulating substrate; and a hollow hole of the insulating substrate and a driver provided from a lower surface of the insulating substrate. And a middle terminal having one end inserted through a through hole of the plate to pivotally mount the driver plate, and the other end disposed from the bottom surface of the insulating substrate to one side surface. An end portion is formed so as to extend on the base electrode layer and the insulating substrate, and the plating layer is formed on the base electrode layer and the resistor so as to include the extended portion formed in the resistor, According to this configuration, it is possible to provide a variable resistor that does not cause unstable output characteristics.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first aspect of the present invention, a horseshoe-shaped resistor having a hollow hole at a substantially center and an upper surface is provided, and electrical resistance is provided between both ends and the upper surface of the resistor. An insulating substrate having a pair of base electrode layers provided from the side surface to the lower surface and a plating layer provided so as to cover the base electrode layer, and a protrusion having a through hole protruding toward the insulating substrate. A driver plate provided with a brush that slides on a resistor of the insulating substrate, and one end of the driver plate is inserted from a lower surface of the insulating substrate into a hollow hole of the insulating substrate and a through hole of the driver plate. A middle terminal having a plate pivotally attached and the other end disposed from the bottom surface to one side surface of the insulating substrate, wherein the end of the resistor of the insulating substrate is connected to the base electrode layer and the insulating substrate. And the plating layer is formed on the base electrode layer and the resistor so as to include the extended portion formed in the resistor. According to this configuration, the resistor of the insulating substrate is formed. The end of the base is formed on the base electrode layer and the insulating substrate, and the plating layer is formed on the base electrode layer and the resistor so as to include the extended portion of the resistor. Even if moisture is added to the inside of the base electrode layer, Ag does not expose the base electrode layer due to the extension, so that migration occurs as in the conventional case, and the pair of base electrode layers Does not become electrically conductive, and as a result, the output characteristic of the variable resistor has an effect of always obtaining a stable one.

Hereinafter, a variable resistor according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is an exploded perspective view of a variable resistor according to an embodiment of the present invention, FIG. 2 is a side sectional view of the variable resistor,
FIG. 3 is a side sectional view showing an electrode portion of an insulating substrate in the variable resistor, and FIG. 4 is a top view of the insulating substrate in the variable resistor.

In FIG. 1 to FIG. 4, reference numeral 11 denotes an insulating substrate made of ceramic. The insulating substrate 11 has a hollow hole 12 substantially at the center and a horseshoe-shaped resistor 13 provided on the upper surface. The insulating substrate 11 has the resistor 13
Pair of base electrode layers 1 electrically connected at both ends and the upper surface
4 is provided from the side surface to the lower surface. and again,
An end portion of the resistor 13 in the insulating substrate 11 is formed so as to extend on the base electrode layer 14 and the insulating substrate 11, and the plating layer 16 is formed so as to include the extended portion 15 formed in the resistor 13. It is formed on the base electrode layer 14 and the resistor 13. 17 is a metal driver plate,
The driver plate 17 has a protruding portion 18 protruding toward the insulating substrate 11.
A through hole 19 is provided at substantially the center of 8, and a driver groove 17 a is provided on the upper surface of the driver plate 17. A brush 20 is fixed to the lower surface of the driver plate 17, and the brush 20
It comes into sliding contact with the first resistor 13. Reference numeral 21 denotes a metal middle terminal.
2 and the through hole 19 of the driver plate 17, and the driver plate 17 is pivotably connected to the driver plate 17. The other end 23 of the middle terminal 21 is provided from the lower surface of the insulating substrate 11 to one side surface.

Next, a method of assembling the variable resistor according to the embodiment of the present invention will be described.

First, a pair of base electrode layers 14 are printed on the upper surface near one side surface of an insulating substrate 11 made of ceramic prepared in advance, and are passed through a baking furnace (not shown). The base electrode layer 14 is formed.

Next, a horseshoe-shaped resistor 13 is printed on the upper surface of the insulating substrate 11 on which the base electrode layer 14 is formed, and the base electrode layer 14 and the insulating substrate are formed on the end of the horseshoe-shaped resistor 13. After printing the extension portion 15 extending so as to be located on the upper surface of both of them, firing is performed to form the horseshoe-shaped resistor 13 and the extension portion 15.

Next, a resin plating resist (not shown) is printed on the upper surface of the horseshoe-shaped portion of the resistor 13 of the insulating substrate 11 and cured, and then the base electrode layer 14 and the extension portion are formed. After plating of Ni on the upper surface of 15, a plating layer 16 of solder is formed.

Finally, the driver plate 17 is placed on the upper surface of the insulating substrate 11 so that the resistor 13 of the insulating substrate 11 and the brush 20 of the driver plate 17 are in sliding contact with each other. From one end 22 of the middle terminal 21 to the hollow hole 12 of the insulating substrate 11 from below.
And the driver plate 17 is inserted through the through hole 19 of the driver plate 17, and the driver plate 17 is pivotably connected to the driver plate 17.

The operation of the variable resistor constructed as described above according to one embodiment of the present invention will now be described.

A constant voltage is applied to one of the plating layers 16 provided on the upper surfaces of the pair of base electrode layers 14, the other is grounded, and the other end 23 of the middle terminal 21 is connected to an external circuit (not shown). Connecting. Then, by inserting a mating driver (not shown) into the driver groove 17a of the driver plate 17 and rotating the same, the potential of the middle terminal 21 is set to an arbitrary resistance value.

Here, when the variable resistor according to one embodiment of the present invention is used for a long time with water added,
In one embodiment of the present invention, the end of the resistor 13 of the insulating substrate 11 is formed to extend over the base electrode layer 14 and the insulating substrate 11, and the extended portion 15 of the resistor 13 is formed. Plating layer 16 so as to include
4 and the resistor 13, even if moisture is added to the inside of the pair of base electrode layers 14, the extension 15 becomes an obstacle and the Ag of the base electrode layer 14 is not exposed.
g causes migration, and a pair of base electrode layers 1
This has the effect of preventing electrical conduction between the four elements.

[0020]

As described above, the variable resistor according to the present invention has a hollow hole substantially at the center and a horseshoe-shaped resistor provided on the upper surface, and is electrically connected to both ends of the resistor at the upper surface. An insulating substrate having a pair of base electrode layers provided from the side surface to the lower surface and a plating layer provided to cover the base electrode layer, and a protruding portion having a through hole protruding toward the insulating substrate. A driver plate provided with a brush that slides on a resistor of the insulating substrate,
One end is inserted from the lower surface of the insulating substrate into the hollow hole of the insulating substrate and the through hole of the driver plate to pivotally mount the driver plate, and the other end is disposed from the bottom surface of the insulating substrate to one side surface. And an end portion of the resistor of the insulating substrate extending over the base electrode layer and the insulating substrate, and the plating layer including an extended portion of the resistor. Is formed on the base electrode layer and the resistor. According to this configuration, the end of the resistor of the insulating substrate is formed to extend on the base electrode layer and the insulating substrate, and the extension formed on the resistor is formed. Since the plating layer is formed on the base electrode layer and the resistor so as to include the extended portion, even if moisture is added to the inside of the pair of base electrode layers, the extension portion becomes an obstacle and the base electrode is obstructed. Because the Ag of the layer is not exposed As in the conventional case, the migration of Ag does not occur and the pair of base electrode layers are not electrically connected to each other. As a result, the output characteristics of the variable resistor can always be stable. It has.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a variable resistor according to an embodiment of the present invention.

FIG. 2 is a side sectional view of the variable resistor.

FIG. 3 is a side sectional view showing an electrode portion of an insulating substrate in the variable resistor.

FIG. 4 is a top view of an insulating substrate in the variable resistor.

FIG. 5 is a top view of an insulating substrate in a conventional variable resistor.

FIG. 6 is a side sectional view of an insulating substrate in the variable resistor.

DESCRIPTION OF SYMBOLS 11 Insulating substrate 12 Hollow hole 13 Resistor 14 Base electrode layer 15 Extension 16 Plated layer 17 Driver plate 18 Projection 19 Through hole 20 Brush 21 Middle terminal 22 One end 23 Other end

Claims (1)

[Claims] 1. A pair of bases having a hollow hole substantially in the center, a horseshoe-shaped resistor provided on the upper surface, and electrically connected at both ends and the upper surface of the resistor and provided from the side surface to the lower surface. An insulating substrate having an electrode layer and a plating layer provided so as to cover the base electrode layer; and a protruding portion having a through hole protruding toward the insulating substrate, and sliding on a resistor of the insulating substrate. A driver plate provided with a brush, and one end of the driver plate is pivotally mounted by inserting one end from the lower surface of the insulating substrate into the hollow hole of the insulating substrate and the through hole of the driver plate, and the other end is insulated. A middle terminal disposed from the bottom surface to one side surface of the substrate, wherein an end of the resistor in the insulating substrate is formed to extend on the base electrode layer and the insulating substrate, and A variable resistor, wherein the plating layer is formed on the base electrode layer and the resistor so as to include the extended portion formed.