JPS6030101A - Variable resistor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a variable resistor.

The basic configuration of a variable resistor is as shown in Figure 1.
A film-like current collector 2 and a film-like resistor 3 are arranged side by side on the top, and the resistance value is changed by moving a slider 4 that slides on the current collector 2 and the resistor 3. It is something that forces you to do something.

The relationship between the amount of slider movement and the resistance value of this variable resistor is as shown in Fig.
There are some that have the characteristics shown below. The present invention is directed to a variable resistor having characteristics as shown by curve B.

FIG. 3 shows the state of the resistor 3 in a conventional variable resistor having characteristics as shown by curve B.

As shown in this figure, in the conventional method, the thickness of the resistor 3 is changed stepwise by overcoating, and the resistance value is changed non-linearly in response to the change. The method for manufacturing the resistor 3 is to apply a first layer of resistance paste on the substrate 1, then change the length and apply the second layer on top of the first layer and the third layer on top of the second layer. Then, the resistor paste layers are made thicker from one end to the other in order such as the fourth layer, but the workability in manufacturing the resistor 3 is poor, and there may be steps between each layer. Due to the presence of this step, the sliding movement of the slider is not smooth, and although the characteristic curve as shown in track 14B in Fig. 2 would normally be obtained, the characteristic curve also changes at the step portion. Steps occur, making it impossible to obtain a smooth change in resistance value.

The purpose of the present invention is to eliminate the drawbacks of the prior art as mentioned above,
It is an object of the present invention to provide a variable resistor that is easy to manufacture, allows smooth movement of a slider, and has good resistance value change characteristics.

In order to achieve this object, the present invention forms dot-shaped first resistance parts having different areas and intervals on the surface of a substrate, and on top of the first resistance parts, a first resistance part with an electrical resistance value of An embodiment of the present invention will be described with reference to the drawings, which is characterized in that six different continuous layers of second resistance portions are formed. FIG. 4 is a plan view of the screen used in the present invention, FIGS. 5 and 6 are partial plan views, top views, and cross-sectional views of a large resistance substrate using the screen to form the first resistance section, and FIGS. The figure shows a second resistor section 1fr on top of the first resistor section.
FIG. 2 is a partial cross-sectional view of a vaporized resistor substrate.

On the surface of the insulating substrate 210 made of a ceramic plate, glass plate, synthetic resin plate, etc., and on both sides of the area where the later-described resistive layer is to be formed, conductive parts are formed by screen printing using a conductive paste as shown in No. 51. 22 and 22 are formed respectively.

Next, the first resistive portion 23 is formed between the conductive portions 22° and 22 by screen printing, and the screen 24 used at this time has a through-hole pattern as shown in FIG. . That is, a large number of rectangular through holes 25 are formed in the screen 24 in a lined manner. The area of 25 gradually increases,
In addition, the distance between the through holes 25 is gradually narrowed, and therefore the aperture ratio gradually differs in each of the through hole drilling regions 26A to 26G.

The first resistor section 23 is formed on the insulating substrate 21 using this screen 24, and the subsequent state is shown in FIGS. 5 and 6. Since the screen 24 has the above-mentioned through-hole pattern, the dot-shaped and generally strip-shaped first resistance section 23 formed accordingly is located in the resistance section forming area 27.
In A to 27G (see Figure 5), the first
The formation area of the resistance portion 23 gradually differs. This first
The resistor portion 23 is formed using a resistor paste having a relatively low electrical resistance value so as to obtain a predetermined electrical resistance value at each position.

Next, as shown in FIG.
The resistor portion 28 is formed by screen printing. As mentioned above, the resistor part 23 uses paste with a high resistance value,
Moreover, since the formation area of the first resistance section 23 per unit area, in other words, the density of the first resistance section 23 gradually changes in each of the resistance section formation regions 27A to 27G, the first resistance section 23 is gradually changed. ζ Therefore, the characteristics shown by curve B in FIG. 2 are almost obtained.

Therefore, the second resistance part 28 has the role of filling between each first resistance part 23 and smoothing the change characteristics of the resistance value. Karakuri JR-A is running. Note that the gaps between the first resistor parts 23 may be very fine depending on the location, and if the viscosity of the resistance paste forming the second resistor part 28 is high, the first resistor parts 23 will not fit into the fine gaps. A void may be formed in between.

When voids are formed in this manner, the electrical resistance value changes, making it impossible to obtain desired resistance characteristics. Therefore, it is desirable that the resistance paste forming the second resistance part 28 has good permeability, such as by increasing the content of a solvent or by decreasing the content of a viscous agent.

The fc second resistance section 28 also has the role of flattening the surface of the resistance layer and smoothing the sliding surface of the slider.

In the above embodiment, the case where the planar shape of the first resistor section 23 is a square has been described, but the present invention is not limited to this.
Instead, it can be a triangle, a polygon larger than a pentagon, or a circular shape.

The present invention can be applied not only to so-called sliding type variable resistors but also to rotary variable resistors. The present invention has the above-described configuration, has good resistance value change characteristics, and has a slider. The movement is smooth, and since variable resistors having such resistance parts are used in multiple stages, there is an advantage that there is little movement error.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a resistance board of a variable resistor, Fig. 2 is a resistance value characteristic diagram, Fig. 3 is a partial cross-sectional view of a conventional resistance board, and Fig. 4 is a plan view of a resistance board of a variable resistor.
Figures 1 through 7 are sixth diagrams explaining the present invention in detail. Figure 4 is a plan view of the screen, and Figures 5 and 6 show a part of the resistor board of the present invention in the process of being manufactured. A plan view and a partial cross-sectional view, and FIG. 7 is a cross-sectional view showing the state of the resistor board after it has been manufactured. 21... Insulating substrate, 23... First resistance section, 27A to 27G... Resistance section formation region, 28
...Second resistance section. Figure 1 Figure 2 Figure 3 Figure 4 Figure 6 Death l Figure 7

Claims (1)

[Scope of Claims] (1) Dot-shaped first resistance parts having different areas and intervals are formed on the substrate surface in a substantially band shape, and on the first resistance parts are formed a series of dot-shaped first resistance parts having different electrical resistance values. A variable resistor characterized in that a second resistor section is formed in six layers. (2. Scope of Claims Paragraph (1), wherein the variable resistor is characterized in that the second resistance section has a smaller electrical resistance value than the first resistance section. (3) Scope of Claims The variable resistor according to item (1), wherein the resistance paste for forming the second resistance portion is a paste with good permeability.