JPS6152561B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a substrate type variable resistor obtained by etching a resistance circuit board having a laminated structure of a resistor layer and a conductor layer on an insulating substrate.

Figure 1 is a plan view of a conventional substrate type variable resistor.
2 is an enlarged partial sectional view taken along line aa' in FIG. 1, and FIG. 3 is an equivalent circuit diagram of FIG. 1. Figure 1~
In FIG. 3, a substrate type variable resistor A includes only an insulating region 1 and a conductive layer C, which are formed by etching away the resistor layer R and the conductive layer C on the insulating substrate B to expose the surface of the insulating substrate 1. Resistance region 2 in which the surface of resistor layer R is exposed by etching away, and conductive region 3 in which neither resistor layer R nor conductor layer C is removed and the surface layer is a conductive layer. It consists of three areas. The conductive region 3 includes an electrode 31, an electrode 3
2, an intermediate electrode 33, and a large number of electrode pieces 34, and the resistance region 2 becomes the strip-shaped resistor 21 between the electrodes 31 and 32.

By sliding the S section in Figure 1 with a brush,
Output voltage V ₁ is output for input voltage V ₀ .

By the way, in manufacturing the above-mentioned conventional substrate type variable resistor, when forming the resistance region 2 by etching only the conductor layer C, there is often a problem of over-etching.

That is, since the resistance Ri of the strip resistor 21 between two adjacent electrode pieces 34 is proportional to the gap width between the two adjacent electrode pieces, when overetching occurs on the side surface of the electrode piece 34, the resistance increases. Ri
increases, and as a result, the total resistance (Ri) of the strip resistor 21 also changes, resulting in a problem that the total resistance varies between products.

The present invention proposes a novel substrate-type variable resistor in which the above-mentioned problems are solved, and in which a branch resistor layer continuous with one side of the strip resistor is formed at the intermediate electrode lead-out portion of the strip resistor. It is characterized by the fact that the conductor layer thereon is formed so as not to overlap the band-shaped resistor.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

4 is a plan view of an embodiment of the present invention, FIG. 5 is an enlarged sectional view taken along line bb' in FIG. 4, and FIG. 6 is an equivalent circuit diagram of FIG. 4. Each part in FIGS. 4-6 is designated by the same reference numeral as the corresponding part in FIGS. 1-3. However, unlike the case shown in FIG. Each tip of the electrode piece 34 is connected to the side band portion 21 opposite to the side 211 of the band-shaped resistor 21 from which the electrode piece 34 is led out.
not covered. Therefore, there is no electrode piece 34 on the strip resistor 21, and in this embodiment,
The strip resistor 21 itself is the continuous resistor strip described above. R ₁₁ , R ₁₂ , -Ri ₁ ...Rn ₁ shown in Figure 6
represents the resistance of the resistor protrusion 22.

In the variable resistor shown in FIGS. 1 and 4, if the length of the strip resistor 21 between the electrodes 31 and 32 is L, and the flat electrode width of the electrode piece 34 is l, then the first
In the variable resistor shown in the figure, the total resistance of the strip resistor 21 is a value proportional to (L−nl), whereas in the embodiment shown in FIG. 4, the total resistance of the resistor 21 is is proportional to L, and therefore, there is no influence of l, in other words, there is no influence of the presence or absence of overetching of the side surface of the electrode piece 34.

In the embodiment shown in FIG. 4, as described above, the electrode piece 34 is connected to the strip resistor 2 through the resistor protrusion 22.
It is conducting with 1. The resistance of this resistor protrusion 22
Ri ₁ does not affect the total resistance of the strip resistor 21 at all.

According to the present invention, since a single resistor circuit board having a laminated structure of a resistor layer and a conductor layer on an insulating substrate is manufactured by etching, it is ultra-thin, lightweight, and highly suitable for mass production. There are few points and it is cheap.
In addition, the resistance between the electrode pieces due to overetching on the side surface of the electrode piece 34 in FIG.
Since the problem of Ri variation is resolved, the output voltage
The linearity of V ₁ is improved. Furthermore, in the case of FIG. 4, the effective length of the strip resistor 21 between the electrodes 31 and 32 as a resistor is longer than that in FIG.
In order to obtain a total resistance value similar to that of the strip resistor shown in FIG. 1, it is possible to design the strip resistor 21 to have a wider width. Variations in values can also be reduced from this aspect.

The present invention is not limited to the above embodiments, but includes various modified embodiments. For example, the strip resistor may have a linear shape, an arc shape, or another shape, and the width of the continuous resistor strip where the electrode piece 34 is not provided is the same as that of the electrode 34.
It is not necessary that the width be constant between 1 and 32, and the width may change toward one side of the electrode. Further, the tip of the electrode piece 34 shown in FIG. 4 may extend above the band-shaped resistor 21 as long as it does not cover the side band portion 212 of the band-shaped resistor 21.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a conventional example, FIG. 2 is an enlarged sectional view taken along line a-a' in FIG. 1, and FIG. 3 is an equivalent circuit diagram of FIG. FIG. 4 is a plan view showing an embodiment of the present invention;
FIG. 5 is an enlarged sectional view taken along line bb' in FIG. 4, and FIG. 6 is an equivalent circuit diagram of FIG. 4. I... Insulating substrate, R... Resistor layer, C... Conductor layer, 22... Resistor protrusion continuous with strip resistor 21, 21... Strip resistor, 31, 32... Electrode, 33 ...Intermediate electrode, 34...electrode piece.

Claims (1)

[Scope of Claims] 1. Using a laminated structure substrate in which a resistor layer is provided as a lower layer and a conductor layer as an upper layer on an insulating substrate, a portion obtained by etching away the upper conductor layer from the laminated structure becomes a resistor, It consists of a resistor circuit board in which the portion of the laminated structure left intact serves as an electrode, and electrode pieces for leading out intermediate electrodes are temporarily installed at a number of predetermined locations on a band-shaped resistor formed between the electrodes at both ends. In the device, a branched resistor layer continuous with one side of the strip resistor is formed at the intermediate electrode lead-out location, and the conductor layer is disposed on the branch resistor layer. A substrate type variable resistor characterized in that the electrode piece is formed so as not to hang over the substrate. 2. The substrate type variable resistor according to claim 1, wherein a resistor protrusion is formed between the tip of the electrode piece on the branched resistor layer and one side of the band-shaped hypobody.