JPH0786009A - Chip type variable resistor - Google Patents

Abstract

PURPOSE:To give a specific resistance value to a high resistance value part while reducing the variation ratio of the resistance value to the turning angle of a slider in a low resistance value part by providing an arc resistor film with plural resistance value regions in different resistance values per unit area. CONSTITUTION:An arc resistor film 12 is electrically connected to upper surface electrodes 13a, 14a on both connecting electrode terminals 13, 14. Next, the first resistor films 12a, 12b respectively having proper lengths of L1, L2 from the upper surface electrodes 13a, 14a are electrically connected to both ends of the second resistor film 12c in less resistance value per unit area than those of the first resistor films 12a, 12b. At this time, the resistance value can be finely and precisely adjusted in the region of the second resistor film 12c by turning a slider within the range of proper turning angle on the arc resistor film 12. On the other hand, the resistance value between both connecting electrode terminals 13, 14 can have the whole specified nominal resistance value by giving specific resistance value to the first resistor films 12a, 12b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a chip type variable resistor constructed so that its resistance value can be arbitrarily adjusted.

[0002]

2. Description of the Related Art Generally, a chip type variable resistor of this type is described in, for example, Japanese Utility Model Laid-Open No. 58-44805.
In addition, as shown in FIGS. 9 and 10, an arc-shaped resistance film 2 is provided on the upper surface of the insulating substrate 1, and both ends of the resistance film 2 are a pair of connection electrode terminals 3 on one side surface of the insulating substrate 1. Four
This arc-shaped resistance film 2 is formed so as to be electrically connected to
On the other hand, by slidingly contacting the slider 5 which is rotatably pivoted to the insulating substrate 1, the slider 5 is rotated within the range of an appropriate rotation angle θ ' The resistance value between one of the connecting electrode terminals 3 and 4 and the intermediate terminal 6 electrically connected to the slider 5 is adjusted in the range of r1 ′ to r2 ′. I am configuring.

[0003]

However, in this conventional chip type variable resistor, both connection electrode terminals 3 and 4 are used.
Since the width dimension and the thickness dimension of the arc-shaped resistance film 2 between the two are substantially uniform over the entire length of the resistance film 2 in the length direction, the both connection electrode terminals 3,
As shown in FIG. 11, the resistance change characteristics between one of the electrode terminals and the intermediate terminal 6 are as follows:
Thus, a substantially straight line having a large inclination angle is formed to connect between the nominal total resistance value R between the connection electrode terminals 3 and 4.

That is, as shown in FIG. 11, the resistance change characteristic of the conventional chip-type variable resistor is a substantially straight line that relatively inclines, so that the resistance value of the slider 5 depending on the unit rotation angle δθ is changed. The change value δr ′ is large, in other words, the change rate of the resistance value with respect to the rotation angle of the slider 5 is large, so that one of the connection electrode terminals 3 and 4 and the intermediate terminal 6 are connected. There is a problem that the resistance value cannot be finely and precisely adjusted.

The present invention solves this problem and reduces the resistance value to
It is a technical object to provide a variable resistor that can be finely and precisely adjusted.

[0006]

In order to achieve the above-mentioned technical objects, the present invention provides an insulating substrate with arc-shaped resistive films on both connecting electrode terminals provided on the insulating substrate at both ends of the resistive film. In a chip type variable resistor formed so as to be electrically connected and rotatably mounted so that a slider electrically connected to an intermediate terminal is slidably in contact with the resistance film. The arc-shaped resistance film has a plurality of resistance value regions having different resistance values per unit area.

[0007]

As described above, the fact that the arcuate resistance film has a plurality of resistance value regions having different resistance values per unit area means that the resistance film has a small resistance value per unit area on the resistance film. That is, the large part is formed, and as a result, in the part where the resistance value per unit area is small, the variable characteristic of the resistance value between one of the connecting electrode terminals and the intermediate terminal is The inclination of can be made gentle, in other words, the change rate of the resistance value with respect to the rotation angle of the slider can be reduced. on the other hand,
By setting a portion having a large resistance value per unit area to a predetermined resistance value, the resistance value between the connection electrode terminals can be set to a predetermined nominal total resistance value.

[0008]

Therefore, according to the present invention, the resistance value of the chip type variable resistor can be finely adjusted with high accuracy while keeping the nominal total resistance value of the chip type variable resistor at a predetermined value. It has the effect that

[0009]

Embodiments of the present invention will be described below with reference to the drawings of FIGS.

FIGS. 1 to 3 show an embodiment of the present invention. In this figure, reference numeral 11 denotes a ceramic insulating substrate formed in a chip type. The film 12 is formed in an arc shape centered on the through hole 11 a formed substantially in the center of the insulating substrate 11, and one side surface of the insulating substrate 11 is connected to both ends of the arc resistance film 12. Electrode terminals 13 and 14 are formed.

The electrode terminals 13 and 14 for both connections are
Is the upper surface electrodes 13a, 14a and the lower surface electrodes 13b, 14
b and the side surface electrodes 13c and 14c.

Reference numeral 15 indicates an intermediate terminal made of a metal plate, which is disposed on the lower surface side of the insulating substrate 11.
A hollow shaft 15a that is fitted into the through hole 11a of the insulating substrate 11 is integrally formed therewith.

Reference numeral 16 indicates a slider made of a metal plate disposed on the upper surface side of the insulating substrate 11.
6 is rotatably fitted to the upper end of the hollow shaft 15a, and then caulked the upper end of the hollow shaft 15a so that the hollow shaft 15a is rotatably attached to the insulating substrate 11. The circular arc resistance film 1 is provided on the child 16.
A sliding contact 16a that slidably contacts the 2 is provided.

At this time, the arcuate resistance film 12 is formed.
Is the upper surface electrode 13 of both connection electrode terminals 13 and 14.
a, 14a and a first resistance film 12 electrically connected to the upper surface electrode and having appropriate lengths L1 and L2 from the upper surface electrode.
a, 12b and the first resistance films 12a, 12b whose both ends are electrically connected to the first resistance films 12a, 12b.
Second resistance film 12 having a smaller resistance value per unit area
and c. The first resistance films 12a and 12
The b does not necessarily have to have the same resistance value per unit area.

In this structure, the arc-shaped resistance film 12 is formed.
Since the slider 16 appropriately rotates within the range of the rotation angle θ, the resistance value between one of the connection electrode terminals 13 and 14 and the intermediate terminal 15 is adjusted. However, particularly in the region of the second resistance film 12c on the arc-shaped resistance film 12, fine and precise adjustment can be performed.

That is, as shown in FIG. 4, a region of the second resistance film 12c in the arc-shaped resistance film 12, r1 to r2.
Within the range, the slope of the resistance change characteristic between one of the connection electrode terminals 13 and 14 and the intermediate terminal 15 can be made gentle. In other words, the unit rotation of the slider 16 can be reduced. The rate of change δr of the resistance value with respect to the angle δθ can be reduced, while the resistance value between the connection electrode terminals 13 and 14 is
By setting the resistance films 12a and 12b to have a predetermined resistance value, the resistance value between the connection electrode terminals 13 and 14 can be set to a predetermined nominal total resistance value.

In the above embodiment, on the insulating substrate 11,
To form the both connection electrode terminals 13 and 14, and the first resistance films 12a and 12b and the second resistance film 12c, for example, as shown in FIG. On the upper surface of the insulating substrate 11, both connection electrode terminals 1
3 and 14, upper surface electrodes 13a and 14a are formed on the lower surface of the insulating substrate 11, and lower surface electrodes 13b and 14b of both connecting electrode terminals 13 and 14 are formed on the lower surface of the insulating substrate 11. Then, as shown in FIG. 11 on the upper surface,
Of the resistance films 12a and 12b are formed so that one ends thereof partially overlap the upper surface electrodes 13a and 14a, and then the resistance films 12a and 12b are formed between the other ends of the first resistance films 12a and 12b. Second resistance film 12c so as to be electrically connected
To form.

Then, on one side surface of the insulating substrate 11, the side surface electrode 13 of both connection electrode terminals 13 and 14 is formed.
c and 14c are formed.

Of course, the lower electrode 13b, 14b, the upper electrode 13a, 14a, the first resistance film 12a, 12b, and the second resistance film 12c are formed on the insulating substrate 11 by the present inventor, for example. In the same manner as in the above-mentioned patent application (Japanese Patent Application No. 63-292096 and Japanese Patent Application Laid-Open No. 2-137201), a material plate in which a plurality of the insulating substrates 11 are aligned vertically and horizontally and integrated is used. This is performed for each insulating substrate 11, then the material plate is divided into rods, and in this rod-shaped state, the side electrodes 13c and 14c are formed on each insulating substrate 11, and then the insulating substrates 11 are divided. To do.

The present invention is not limited to the above-described embodiment, but includes the case where the formation region of the second resistance film 12c having a small resistance value per unit area in the above-mentioned embodiment is appropriately changed. By changing the formation region of the second resistance film 12c, the resistance changing characteristic can be set arbitrarily. 5 (1) and 5 (2) show an example of the arc-shaped resistance film pattern and its resistance change characteristics when the formation region of the second resistance film 12c is changed.

FIG. 5A shows a second resistance film 12c.
Shows an example in which the first resistance film 12a and the first resistance film 12b are integrally provided so as to join the divided second resistance film 12c. The change characteristic is as shown in (1) b.

In (2) a of FIG. 5, most of the arcuate resistance film is formed of the second resistance film 12c, one end of which is connected to one of the connection electrode terminals 13, and the first resistance film 12a, 12b
Integrated into the other connecting terminal 14 and the second resistance film 12c.
In this example, the resistance change characteristics are as shown in (2) b.

In FIG. 5, the same reference numerals as those shown in FIGS. 3 and 4 indicate the same parts as those shown in FIGS.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view of a chip variable resistor according to a first embodiment of the present invention.

FIG. 2 is a partially cutaway plan view of FIG.

FIG. 3 is a perspective view of the insulating substrate in FIG.

FIG. 4 is a diagram showing resistance change characteristics in the first embodiment.

FIG. 5 is a plan view showing arcuate resistive film patterns in the second and third embodiments of the present invention, and a diagram showing resistance change characteristics in each of them.

FIG. 6 is a perspective view of an insulating substrate.

7 is a perspective view showing a state where a lower surface electrode and an upper surface electrode of a connecting electrode terminal are formed on the insulating substrate of FIG.

8 is a perspective view showing a state in which a first resistance film and a second resistance film are formed on the insulating substrate of FIG.

FIG. 9 is a vertical sectional front view of a conventional chip type variable resistor.

FIG. 10 is a partially cutaway plan view of FIG.

FIG. 11 is a diagram showing resistance change characteristics of a conventional chip type variable resistor.

[Explanation of symbols]

 11 Insulating Substrate 12 Arc Resistive Films 12a, 12b First Resistive Film 12c Second Resistive Film 13, 14 Connection Electrode Terminal 15 Intermediate Terminal 16 Slider

Claims (1)

[Claims] 1. An insulating substrate is formed with an arc-shaped resistance film such that both ends of the resistance film are electrically connected to both connecting electrode terminals provided on the insulating substrate, and an electrical resistance is provided to an intermediate terminal. In a chip type variable resistor in which a slider connected to is rotatably mounted so as to slidably contact the resistance film, the arc-shaped resistance film has a resistance value per unit area. A chip-type variable resistor having a plurality of different resistance value regions.