JPH02275603A - Variable resistor and sensor using it - Google Patents

Abstract

PURPOSE:To simplify contact structure and improve compactness and durability by using a contact which consists of a conductive rubber and whose at least one section is in projecting shape. CONSTITUTION:A pair of electrodes 10 and 11 which are isolated each other, a plane-shaped resistor 12 which conduct with them and which consists of two parts which are placed so that it is divided into two by a gap, and a contact 13 which consists of a conductive rubber and has a contact part whose section is in approximate projecting shape are provided between the electrodes. The wide surface of the resistor 12 and the contact part of the contact 13 are opposed so that the direction connecting a pair of electrodes and that of section in approximate projection shape agrees each other and at the same time a pair of electrodes 10 and 11 and the relative distance between the resistor 12 and the contact 13 changes according to the force applied externally. The position of the resistor 12 which conducts through the contact 13 due to pressurized applied externally, namely the practical length of resistor between a pair of electrodes changes and the resistance changes. It simplifies structure, miniaturizes the body, and also improves durability.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a variable resistor and a sensor using the same.

(Prior art) Figure 2 shows an example of a conventional variable resistor, for example,
This is disclosed in Japanese Patent No. 77520. That is, at the bottom of a substantially box-shaped housing 1, there are two flat resistors 2.
3 are placed side by side on the same dirt floor at one end with a certain gap 4 in between. Further, a flat contact 5 which is flexible and has a length spanning the resistor 2.degree. 3 is provided on the upper part of the housing 1 so as to be bent toward the resistor 2.3. Further, the contact point 5 is connected to a push button 7 which is urged upwardly in the housing 1 by a coil spring 6. Furthermore, two terminals 8.9 are connected to the other end of the resistor 2.3.

In the above configuration, when the push button 7 is pressed and the contact 5 is moved toward the resistors 2 and 3, the contact 5 comes into contact with one end of the resistors 2 and 3, making them conductive. After that, when the push button 7 is further pressed, the contact area between the resistors 2 and 3 and the contact 5 expands toward the other end side of the resistors 2 and 3, and the resistor becomes conductive via the contact 5. 2 and 3 positions,
That is, the substantial length of the resistors 2, 3 between the terminals 8, 9 is reduced.

Therefore, at the two terminals 8°918 of the variable resistor described above, a resistance value that gradually decreases from almost infinity (non-conducting state) to a predetermined value (conducting state) and then gradually decreases depending on the suppression is obtained. It will be done.

In addition, other conventional variable resistors include those using pressure-sensitive conductive materials. This is designed to change the resistance value between two electrodes by applying pressure between the two electrodes sandwiching a pressure-sensitive conductive material, for example, pressurized conductive rubber.

(Problems to be Solved by the Invention) However, the variable resistor shown in FIG. 2 described above has a complicated structure, is difficult to miniaturize, and has low durability. Also,
For variable resistors using pressure-sensitive conductive materials, it is difficult to obtain parameters that determine the resistance change characteristics, and the characteristics change with repeated use, that is, the reproducibility of the characteristics is low, making it difficult to design. There was a point.

The present invention solves the above-mentioned problems and provides a variable resistor that has a simple structure, is easy to miniaturize, is excellent in durability, and has good reproducibility by easily obtaining parameters of resistance value change characteristics, and a sensor using the same. The purpose is to provide.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes at least a pair of electrodes separated from each other, and a structure in which the pair of electrodes are electrically connected to each other and divided into two by a gap. a planar resistor consisting of two parts, and at least one contact point made of conductive rubber and having at least one contact part with a substantially convex cross section, connecting a pair of electrodes. The wide surface of the resistor and the contact part of the contact are made to face each other so that the direction and the direction of the substantially convex cross section are the same, and the relative distance between the pair of electrodes and the resistor and the contact changes depending on the force applied from the outside. a first +J variable resistor, comprising at least a pair of electrodes spaced apart from each other, and a planar resistor disposed between the pair of electrodes so as to be electrically conductive with both of the electrodes;
at least one contact point made of conductive rubber and having at least one contact portion having a substantially convex cross section;
The wide surface of the resistor and the contact part of the contact point should face each other so that the direction connecting the pair of electrodes and the direction of the substantially convex cross section are the same, and the relative distance between the pair of electrodes, the resistor body, and the contact point should be adjusted from the outside. a second variable resistor configured to change according to applied force; and a pair of electrodes and a resistor provided on one substrate in the second or second variable resistor; A third variable resistor is provided with a contact on the inside of a rubber cover that is formed and deforms in response to an external force applied to the first substrate, and a contact is provided on any one of the first to third variable resistors. A fourth variable resistor in which all parts of the pair of electrodes that the contact portions of contact with are covered with a resistor, and only the sides of the pair of electrodes that are close to each other in any one of the first to third variable resistors. a fifth variable resistor, which is covered by a resistor, and the length between both ends of the substantially convex cross section of the contact portion of the contact is equal to or greater than the distance between the portions of the pair of electrodes that are not covered by the resistor; a sixth variable resistor in which flat surfaces are provided at both ends in the direction of the substantially convex cross section of the contact portion of the contact in any one of the first to fifth variable resistors, and the first to 60th offset. A first sensor having such a variable resistor, a pair of electrodes arranged on a first substrate at a predetermined distance from each other, and a planar resistor arranged between the pair of electrodes, A contact made of conductive rubber and having a contact portion with at least one substantially convex cross section is mounted on a second flexible substrate, and the direction in which the pair of electrodes are connected and the direction of the generally convex cross section are mounted. We propose a second sensor in which the first and second substrates are combined so that the wide surface of the resistor and the contact portion of the contact point are opposed to each other.

(Function) According to the first variable resistor, when no external force is applied, the pair of electrodes are in a non-conducting state due to the gap in the resistor, that is, the resistance value therebetween is almost infinite. When an external force is applied to deform the contact and the contact portion short-circuits the gap, the pair of electrodes become electrically connected and the resistance value therebetween becomes a predetermined initial value. After that, when an external force is further applied and the relative distance between the pair of electrodes and the resistor and the contact changes, the contact deforms in the direction that connects the pair of electrodes, and the contact between the contact and the resistor changes. The area changes and the position of the resistor that conducts through the contact, that is, the substantial length of the resistor between the pair of electrodes changes, thereby changing the resistance value between the pair of electrodes.

In addition, according to the second variable resistor, the resistance value between the pair of electrodes remains a predetermined value even when no force is applied from the outside, and when force is applied from the outside, it is the same as the first variable resistor. Changes to

Further, according to the third variable resistor, when an external force is applied to the rubber cover and the rubber cover is deformed, a contact point provided inside the rubber cover and a pair of electrodes and a resistor provided on one substrate are connected to each other. The distance changes, which changes the resistance between the pair of electrodes, similar to the first or second variable resistor.

Further, according to the fourth variable resistor, the pair of electrodes are not short-circuited by a contact point, and the final resistance value between the pair of electrodes is a value corresponding to the resistance value of the resistor.

Also, according to the fifth variable resistor, a pair of 7?
! The poles will be short-circuited by the contact, and the resistance value at that time will be independent of the resistor.

Further, according to the sixth variable resistor, the contact area between the contact portion of the contact and the resistor does not change after the flat surfaces of both hands contact the resistor or the electrode. The position of the conductive resistor, that is, the substantial length of the resistor between the pair of electrodes does not change, and the resistance value between the pair of electrodes becomes a predetermined final value.

Further, according to the first sensor, a change in resistance value based on the configuration of each variable resistor described above is obtained according to a force applied from the outside, and from the change in resistance value, the force described above or the strain or displacement that causes this force can be obtained. , load, etc. are detected.

Furthermore, according to the second sensor, when a force is applied to the second substrate from the outside and the second substrate is deformed and the relative distance from the first substrate changes, the relative distance between the pair of electrodes and the resistor and the contact also changes. Change. At this time, the contact deforms in the direction that connects the pair of electrodes, and the contact area between the contact part and the resistor changes. The length of the resistor changes, which causes
A change in resistance value can be obtained between a pair of electrodes.

(Example) Figure 1 shows an example of the variable resistor of the present invention.
In the figure, 10.11 is a pair of electrodes, 12 is a resistor, 13 is a contact, 14 is a substrate, 15 is a cavity, and 16 is a rubber cover.
17 and 18 are terminals, and 19 is a fixing ring.

Each of the pair of electrodes 10.11 has a rectangular planar shape as shown in FIG. There is. Note that the substrate 14 is made of a relatively rigid material, such as ceramic.

The resistor 12 is disposed between a pair of electrodes 10.11, and here the gap 15 connects the electrodes 10.11.
It consists of two resistors 12a and 12b divided into two at approximately the center.

The resistor 12a is arranged on the substrate 14 so as to substantially cover one electrode 10 and extend toward the other electrode 11, and the resistor 12b substantially cover the other electrode 11 and extend toward the other electrode 10. ing.

Note that the electrodes 10.11 are made of a metal with good conductivity, such as copper,
Using aluminum or the like, the resistor 12 is formed using carbon ink or the like by a well-known printing wiring technique or the like.

As shown in FIG. 4(a), the contact 13 is a columnar member having a substantially isosceles triangular cross section, and is entirely made of conductive rubber. A portion of the contact point 13 corresponding to the equilateral sides of the substantially isosceles triangle constitutes a contact portion 13a. Also, contact 1
3 is a ridgeline portion 13a corresponding to the apex of the substantially isosceles triangle;
The rubber cover 16 is attached to the rubber cover 16 through a portion corresponding to the base of the substantially isosceles triangle so as to be along the gap 15 and to face each other with a slight distance from each other.

The length of the contact portion 13a in the direction corresponding to the base of the substantially isosceles triangle is approximately the same as the spacing between the electrodes 10 and 11 described above, and the length in the ridge direction is the same as that of the resistor 1.
The length in the direction along the gap 15 of No. 2 is approximately the same as that of No. 2.

The rubber cover 16 is composed of a pressing part 16a that fixes the contact 13 inside thereof, and a support wall part 16b that supports the pressing part 16a so as to be movable with respect to the substrate 14. The rubber cover 16 is fixed around the substrate 14 via a fixing ring 19 on the opening side of the support wall 16b. In addition, in order to prevent side deformation when mounting the contact 13, press the pressing part 6a.
A metal piece or the like may be enclosed inside.

The terminals 17 and 18 are bottle-shaped terminals installed perpendicularly to the substrate 14, and are connected to the electrode 10 and the resistor 12, respectively.
a and electrode 11. It is connected to the resistor 12b. Note that a pattern provided on the back surface of the substrate 14 and connected to the electrode 10 or 11 via a through hole can also be used as the terminal.

Next, the operation of the variable resistor described above will be explained with reference to FIG.

First, when no external force is applied to the suppressing portion 16a, the contact portion 13 of the contact 13 as shown in FIG.
A does not contact either of the resistors 12a and 12b at all. At this time, the resistor 12a.

Since the space between electrodes 12b is non-conductive due to the gap 15, the resistance value between the electrodes 10 and 11, that is, between the terminals 17 and 18 becomes almost infinite.

Next, when an external force is applied to the suppressing part 16a, the contact 13 moves downward, and first, as shown in FIG. and 12
b comes into contact with the cavity 15 side. At this time, the resistor 12a,
12b becomes electrically conductive through the contact portion 13a.

Here, the resistance of the contact 13 and the resistor 12a.

The contact resistance between 12b and contact 13 is the resistor 12a.

12b, the resistance value R between terminals 17 and 18 is R-(Ω/S)ρ (1
) (However, g is the length of the resistors 12a, 12b excluding the gap 15 between the electrodes 10.11, S is the length of the resistors 12a, 12
b is the cross-sectional area, and ρ is the specific resistance of the resistors 12a and 12b).

Furthermore, an external force is applied to the suppressing portion 16a, and the contact point 13
When moves downward, the contact point 1 as shown in Fig. 5(C)
The contact portion 13a of No. 3 is deformed, and the contact portion 13a and the resistor 1
The contact area with 2a and 12b is expanded. At this time, resistor 1
2a and 12b are electrically connected at the outermost position of contact by the contact portion 13a, that is, at a position closer to the electrode 10.11.

This shows that the length Ω in the above equation (1) decreases, and therefore the resistance value R between the terminals 17 and 18 decreases.

When an external force is further applied to the suppressing portion 16a, the contact portion 13a and the resistors 12a, 12
The contact area with b is further expanded, and the above-mentioned conduction position is further closer to electrode 10.11. Therefore, the length Ω in the equation (1) is further reduced, and the resistance value R between the terminals 17 and 18 is also further reduced.

In this way, in the variable resistor, the resistance value between the two terminals 17 and 18 changes from almost infinite, ie, OFF (non-conducting state), to a predetermined value, ie, ON (conducting state), depending on the suppression by the suppressing section 16a. !!, followed by a gradual decrease.

In addition, since the decrease in resistance value at this time depends only on the length of the resistors 12a, 12b that contact the contact portion 13a, the parameters of the resistance value change characteristics are mainly
The specific resistance and cross-sectional area of 2b are obtained, and the design becomes easy. Furthermore, since conductive rubber is used as the contact 13, the contact structure is simple, it is easy to downsize, and it is highly durable.

Further, in the above embodiment, the resistor 12 is replaced with the one shown in FIG.
If a resistor 20 without a gap as shown in b) is used, the resistance value between the two terminals 17 and 18 will simply decrease gradually from a predetermined value in response to the pressure applied to the suppressing portion 16a. Become.

Further, as shown in FIG. 3(C), a pair of 7
Alternatively, two sets of poles and a resistor disposed between the poles may be provided. That is, in the figure, 21, 22, 23° 24 are electrodes, 2
5 is a resistor disposed between the electrodes 21 and 22, and 26 is a resistor disposed between the electrodes 23 and 24. By providing two contacts (not shown) corresponding to these resistors 25 and 26, two independent variable resistors are housed in one unit.

Note that it is also possible to use a resistor 25 or 26 that has a cavity, or a pair of resistors 25 or 26. [t! It is also possible to provide three or more sets of resistors arranged between these.

In addition, in the above embodiment, instead of the contact 13, the
) can also be used. That is,
The contact point 27 is a columnar member whose cross section is approximately isosceles triangular, and is located approximately in the center of a plate-shaped member having a side longer than the length of the base of the approximately isosceles triangle and a side that is the same length as the length in the ridge direction. It has a shape equipped with. The contact 27 is the contact 1
3, the entire body is made of conductive rubber, and the portion corresponding to the equilateral sides of the substantially isosceles triangle and the flat portion continuous thereto constitute a contact portion 27a. Further, the contact point 27 is attached to the rubber cover 16 so that the ridgeline portions 27a' corresponding to the apexes of the substantially isosceles triangle are opposed to each other along the gap portion 15 and at a slight distance from each other.

The length of the contact portion 27a in the direction corresponding to the base of the substantially isosceles triangle is the length of the electrode 1 including the two flat surfaces 278'.
The distance in the ridge line direction is approximately the same as the length in the direction along the gap 15 of the resistor 12.

When an external force is applied to the variable resistor equipped with the contact 27 described above, initially the contact 2
7a and the resistors 12a, 12b come into contact with each other, but eventually, as shown in FIG. do.

After this, even if an external force is applied, the contact area between the contact portion 27a and the resistors 12a and 12b does not increase, and therefore the conduction position does not change, so the resistance value between the terminals 17 and 18 does not change.

In this manner, the contact 27 allows a clear final value to be given to the resistance value between the terminals 17 and 18.

Note that this final value is determined by the parameters of the resistance value change characteristics described above.

FIG. 7 shows other examples of electrode and resistor patterns, which are useful when used in combination with the contact 27 described above.

In FIG. 7(a), 28 and 29 are a pair of electrodes, each having a rectangular planar shape.
9a and lead portions 28b and 29b continuous thereto, and are disposed on a substrate (not shown) such that the long sides of the electrode portions 28a and 29a face each other with a predetermined distance apart.

Further, 30 is a resistor disposed between the pair of electrodes 28 and 29, and in this case, the gap 31
．． Two resistors 3 divided into two near the center between 29
It consists of 0a and 30b. The resistor 30a covers the electrode portion 28a of one electrode 28 up to approximately the center in its short side direction, and extends toward the other electrode 29.
The resistor 30b is disposed on a substrate (not shown) so as to cover the electrode portion 29a of the other electrode 29 up to approximately the center in the short side direction and extend toward the one electrode 28 side.

When an external force is applied to a variable resistor in which the pair of electrodes 28, 29 and the resistor 30 are arranged in correspondence with the contact point 27, the electrodes 10, 29 and the resistor 1 are initially
As in case 2, contact portion 27a and resistors 30a, 30b
Finally, as shown in FIG. 6(b), almost the entire surfaces of two flat surfaces 27a' of the contact portion 27a come into contact with the electrode portions 28a and 29a of the electrodes 28 and 29.

At this time, the electrodes 28 and 29 are electrically connected through the contact 27, and the resistance value therebetween is completely unrelated to the resistor 30.

According to the electrodes 28, 29, resistor 30, and contact 27 described above, the final resistance value between the pair of electrodes 28, 29 can be given an extremely small value that is independent of the resistor between them.

Further, instead of the resistor 30, a resistor 32 without a gap as shown in FIG. , a resistance value is simply obtained that gradually decreases from a predetermined value and finally becomes a value unrelated to the resistor 32.

FIG. 8 shows a main part of another embodiment of the variable resistor of the present invention, and here an example is shown in which a pair of electrodes, a resistor, and a contact point are generally concentric circles as a whole. That is, in the figure, 3
3.34 is a pair of electrodes, each of which covers approximately 2 rings.
It consists of electrode portions 33a, 34a having a planar shape divided into equal parts, and lead portions 33b, 34b continuous thereto.

The electrodes 33 and 34 are mounted on a substrate (not shown) such that the outer and inner peripheries of the electrode portions 33a and 34a are on concentric circles centered on a predetermined point 35, and the end faces face each other with a slight interval. ) is placed on top.

Further, 36 is a resistor disposed between the pair of electrodes 33 and 34, and in this case, a gap 37 is provided between the electrodes 33 and 34.
It consists of two resistors 36a and 36b divided into two along the end face of 34.

The resistor 36a covers the electrode portion 33a of one electrode 33 to approximately the center in the radial direction, and forms part of a small circle centered on the predetermined point 35. The electrode @534a of the electrode 34 is disposed on a substrate (not shown) so as to cover the electrode 34 to approximately the center in the radial direction and to form another part of the small circle.

Further, 38 is a contact point, which is the electrode portion 33a.

A conical member having a bottom surface diameter that is approximately the same as the inner circumference of the electrode portion 34a is mounted concentrically on one end surface of a cylindrical member having an outer diameter that is approximately the same as the outer circumference of the electrode portions 33a and 34a. We are prepared. Like the contact 13, the contact 38 is entirely made of conductive rubber, and the portion corresponding to the circumferential surface of the conical member and the flat portion continuous thereto are the contact portion 3.
8a. Further, the contact point 38 is such that the apex portion 3F3a- corresponding to the apex of the conical member is opposed to the point 35 with a slight distance from it (however, it is drawn quite apart in the drawing for ease of understanding), and It is arranged to be movable in the axial direction in response to external forces.

When an external force is applied to the variable resistor having the above-described configuration and the relative distance between the electrodes 33, 34 and the resistor 36 and the contact 38 becomes smaller, the contact portion 38a of the contact 38 contacts the resistors 36a and 36b. The inner circumferential portion gradually contacts the flat surface 38 of the contact portion 38a in a concentric and solid manner.
Almost the entire surface of a' is the electrode part 33a, 34 of the electrode 33.34.
contact a.

In the variable resistor described above, the electrodes 3B and 34, the resistor 36, and the contact 38 have a substantially -like structure in all radial directions, so the resistance value between the electrodes 33 and 34 is initially determined by the contact with the resistor 36. The value depends on the radial length of the contact point 38 and ultimately becomes an extremely small value that is unrelated to the resistor 36.

Note that a circular resistor having no void portion may be used as the resistor 36, or a circular resistor that covers the entire electrode portion may be used.

Figure 9 shows an example of actual measured values of the resistance change characteristics. Sa0.
An example of a variable resistor in which a three-fin, approximately conical, conductive rubber contact is combined is shown.

Note that as the resistor of the present invention, one having a sheet resistance of 0.5 to 50 Ω/gate is suitable.

FIG. 10 shows a sensor using the variable resistor of the present invention, in which 39 is the first substrate, 40 is the second substrate, 4
1.42 is a pair of electrodes, 43 is a resistor, 44 is a contact, 4
5 is a spacer.

The first substrate 39 is made of a relatively rigid material, such as ceramic, and has a rectangular planar shape. An eleventh plate is located near one end 39a in the longitudinal direction of one surface of the substrate 39.
As shown in the figure, a pair of electrodes 41, 42 and a resistor 43 are provided between them.

The second substrate 40 is made of a flexible material, such as plastic or metal, and has a rectangular planar shape that is slightly shorter than the first substrate 39 . A contact 44 having a columnar shape with a substantially isosceles triangular cross section is attached near one end 40a of one surface of the substrate 40 in the longitudinal direction.

In the first substrate 39 and the second substrate 40, the ridgeline portion corresponding to the apex of the substantially isosceles triangle of the contact point 44 is the resistor 4.
The other ends 39b and 40b in the longitudinal direction are attached substantially parallel to each other via a spacer 45 so as to be in contact with approximately the middle of the three electrodes 41 and 42.

The portion of the contact 44 corresponding to the equilateral sides of the substantially isosceles triangle constitutes a contact portion 44a, and the length of the contact portion 44a in the direction corresponding to the base of the substantially isosceles triangle is the length of the electrode 41.
42, and the length in the ridge direction is approximately the same as the length in the width direction of the resistor 43.

In the sensor, when a force in the direction of arrow 46 is applied to one end 40, a side of the second substrate 40, the one end 40a side
It bends toward the board 39 side. At this time, the relative distance between the resistor 43 and the contact 44 becomes shorter, the contact 44 deforms, and the resistor 43
The contact area between the contact portion 44a and the electrode 41.42 changes.
The substantial length of the resistor 43 between them changes, and its resistance value changes.

The resistance value is the terminal 41a of the electrode 41.42.

It is detected by a detection circuit (not shown) via 42a,
The relative distance between the resistor 43 and the contact 44, in other words, the first
Since it depends on the relative distance between the substrate 39 and the second substrate 40, the force applied to the second substrate 40 or the strain, displacement, load, etc. that causes this force can be determined from the resistance value.

FIG. 12 shows another example of the pattern of electrodes and resistors in the embodiment of FIG. 8.

In TSL 2 (a), 47 and 48 are a pair of electrodes, each consisting of electrode portions 47a and 48a each having a planar shape that divides a ring into approximately four equal parts, and lead portions 47b and 48b that are continuous with the electrode portions 47a and 48a. .

The electrodes 47, 48 have electrode portions 47a, 48a located on concentric circles centered on a predetermined point 49 and are point symmetrical, and lead portions 47b, 48b thereof are located on a concentric circle centered on a predetermined point 49.
A is arranged on a substrate (not shown) so as to extend from approximately the center of each outer side.

Further, 50 is a resistor disposed between the pair of electrodes 47 and 48, which here consists of two semicircular resistors 50a and 50b divided into two by a gap 51. The resistor 50a covers the electrode portion 47a of the first electrode 47 up to approximately the center in the radial direction.
b is disposed on a substrate (not shown) so as to cover the electrode portion 48a of the other electrode 48 to approximately the center in the radial direction.

According to the electrodes 47 and 48 and the resistor 50 described above, the eighth
Since the area of the electrode portion is smaller than in the example shown in the figure, the length of the resistor between the electrodes is substantially longer, and a large resistance value can be obtained.

Further, in FIG. 12(b), 52 and 53 are a pair of electrodes, each consisting of electrode portions 52a and 53a each having a planar shape that roughly divides a ring into two, and lead portions 52b and 53b that are continuous with the electrode portions 52a and 53a. There is. The electrode 52.53
is arranged on a substrate (not shown) such that its electrode portions 52a and 53a are on concentric circles centered on a predetermined point 54, and their end faces face each other with a slight interval between them.

Further, 55 is the pair of electrodes 52. -53, here, it consists of two semicircular resistors 55a and 55b divided into two by a gap 56. The resistor 55a is disposed on a substrate (not shown) so as to completely cover the electrode section 52a of one electrode 52, and the resistor 55b is disposed so as to entirely cover the electrode section 53a of the other electrode 53.

According to the electrodes 52 and 53 and the resistor 55 described above, since the electrode parts are all covered with the resistor, the electrodes are not short-circuited by contacts, and the final resistance value is the resistance value of the resistor. The value corresponds to

Further, in FIG. 12(c), 57 and 58 are a pair of electrodes, each consisting of electrode portions 57a and 58a each having a planar shape that divides the ring into approximately four equal parts, and lead portions 57b and 58b continuous with the electrode portions 57a and 58a. ing. The electrodes 57 and 58 are the electrode portions 57a.

58a is on a concentric circle centered on five predetermined points and is point symmetrical, and its lead portion 57b.

58b is disposed on a substrate (not shown) so as to extend from near one outer end of each of the electrode portions 57a and 58a.

Further, 60 is a resistor disposed between the pair of electrodes 57 and 58, which here consists of two semicircular resistors 60a and 60b divided into two by a gap 61. The resistor 60a is disposed on a substrate (not shown) so as to completely cover the electrode section 57a of one electrode 57, and the resistor 60b is disposed so as to entirely cover the electrode section 58a of the other electrode 58.

According to the electrodes 57 and 58 and the resistor 60 described above, the first
Since the area of the electrode portion is smaller than in the example shown in FIG. 2(b), the length of the resistor between the electrodes is substantially longer, and a large resistance value can be obtained.

Note that the patterns of the electrodes and resistors and the shapes of the contacts described above are just examples; for example, the patterns of the resistors may be shaped like comb teeth, or the shape of the contacts may be approximately semicircular in cross section.

(Effects of the Invention) As explained above, according to the present invention, since a contact is made of conductive rubber and has a contact portion with at least one substantially convex cross section, the contact structure is simplified and the contact is made smaller. This makes it easier to use and also increases durability. In addition, a planar resistor is provided between a pair of electrodes separated from each other and consists of two parts arranged so as to be electrically conductive with each other and divided into two parts by a gap, and the above-mentioned contact points are attached to these two parts in a substantially convex shape. are arranged to face each other so that the direction of the cross section matches the direction connecting the pair of electrodes, and the relative distance between the pair of electrodes, the resistor, and the contact point changes according to the force applied from the outside. It changes from a non-conducting state to a conducting state depending on the force, and then the contact area between the contact and the resistor changes depending on the force applied from the outside, and the position of the resistor that conducts through the contact, that is, the pair of The effective length of the resistor between the electrodes changes, and a resistance value corresponding to the external force is obtained between the pair of electrodes, creating a device that combines an on-off switch and a variable resistor. can get. In addition, at this time, the resistance value between a pair of electrodes depends only on the length of the contact portion between the contact and the resistor, so parameters that determine the resistance change characteristics can be easily obtained, and Since it does not use materials such as pressure-sensitive conductive rubber whose characteristics change with repeated use, the reproducibility of resistance value change characteristics is good, and therefore design is easy.

Further, according to the variable resistor of the present invention, since a resistor is provided between the pair of electrodes and conductive to both sides, the resistance value between the pair of electrodes simply decreases in response to the force applied from the outside. .

Further, according to the variable resistor of the present invention, a pair of electrodes and a resistor are provided on one substrate, the pair of electrodes and the resistor are formed so as to cover the one substrate, and the variable resistor responds to a force applied from the outside. Since the contact point is provided inside the rubber cover that deforms due to the rubber cover, the contact point can be held by the rubber cover, and a restoring force can be given to the contact point against the force applied from the outside. Therefore, it is possible to realize a bush type variable resistor with an extremely simple structure as a whole.

Further, according to the variable resistor of the present invention, all parts of the pair of electrodes that are in contact with the contact portions of the contacts are covered with the resistor, so that the pair of electrodes are not short-circuited by the contacts, and the pair of electrodes are not short-circuited by the contacts. A final value corresponding to the resistance value of the resistor is obtained as the resistance value between the electrodes.

Further, according to the variable resistor of the present invention, only the sides of the pair of electrodes that are close to each other are covered with the resistor, and the length between both ends in the direction of the substantially convex cross section of the contact portion of the contact is Because the spacing was greater than the distance between the parts of the electrodes that are not covered by the resistor, the pair of electrodes would eventually be shorted together by the contact, and the final value of the resistance between the pair of electrodes would be independent of the resistor. can get.

Further, according to the variable resistor of the present invention, flat surfaces are provided at both ends in the direction of the substantially convex cross section of the contact portion of the contact, so that the contact area between the contact portion of the contact and the resistor is such that both flat surfaces have resistance. Therefore, the position of the resistor that conducts through the contact point, that is, the effective length of the resistor between the pair of electrodes, does not change after it contacts the body or the electrode, and the resistance between the pair of electrodes does not change. A clear final value is obtained.

Further, according to the sensor of the present invention, a change in resistance value based on the configuration of each variable resistor described above can be obtained in accordance with an externally applied force, and from the change in resistance value, the force described above or the distortion that causes this force can be obtained. , displacement, ir:1 fold, etc. can be detected.

Further, according to the sensor of the present invention, a pair of electrodes are arranged on the first substrate at a predetermined distance from each other, and a planar resistor is arranged between the pair of electrodes (7, flexible A contact made of conductive rubber and having a contact portion with at least one substantially convex cross section is mounted on a second substrate having a conductive rubber, and the direction in which the pair of electrodes are connected and the direction of the generally convex cross section are the same. Since the first and second substrates are combined so that the wide surface of the resistor and the contact portion of the contact face each other, the contact can be held by the second substrate, and the contact can be protected against external forces applied to the contact. It is possible to provide a restoring force, and therefore, it is possible to realize a sensor having an extremely simple configuration as a whole.

[Brief Description of the Drawings] Fig. 1 is a sectional view showing one embodiment of the variable resistor of the present invention;
Figure 2 is a cross-sectional view showing an example of a conventional variable resistor, Figures 3 (a), (b), and (c) are plan views showing examples of patterns of electrodes and resistors, and Figures 4 (a) and (b). 5(a), (b), (c), and (d) are main part sectional views showing changes in the contact state between the contact and the resistor, and FIGS. 6(a) and (b). ) is a cross-sectional view of the main part showing the final contact state between the contact and the resistor, FIGS. 7(a) and 7(b) are plan views showing other pattern examples of the electrode and resistor, and FIG. FIG. 9 is a graph showing an example of an actual resistance value change characteristic, and FIG. 10 is a sensor using the variable resistor of the present invention. 11 is a plan view of the first substrate in FIG. 10, and FIG. 12 (a), (b), and ('c) are electrodes and resistors in the embodiment of FIG. 8. FIG. 7 is a plan view showing another example of a body pattern. 10, 11. 21. 22. 23. 24. 2
8゜29. 33. 34. 41. 42. 47.
48°52.53, 57.58...electrode, 12.2
0°25, 26. 30. 32. 36. 43.
50°55.60...Resistor, 13,27.38.
44... Contact, 14, 39.40... Board, 15,
31゜37.51.56.61...Gap, 16...
・Rubber cover

Claims (8)

[Claims] (1) A planar resistor consisting of at least a pair of electrodes separated from each other, and two parts disposed so as to be electrically conductive between the pair of electrodes and divided into two by a gap, and a conductive rubber. and at least one contact having a contact portion with at least one substantially convex cross section, and the resistor is wide so that the direction connecting the pair of electrodes and the direction of the generally convex cross section coincide with each other. A variable resistor characterized in that a surface and a contact portion of a contact face each other, and the relative distance between a pair of electrodes, a resistor, and the contact changes in accordance with an external force. (2) At least a pair of electrodes spaced apart from each other, a planar resistor disposed between the pair of electrodes so as to be electrically conductive with both electrodes, and at least one of the electrodes is made of conductive rubber and has a substantially convex cross section. at least one contact having a contact portion formed by the resistor, and the wide surface of the resistor and the contact portion of the contact facing each other so that the direction in which the pair of electrodes are connected and the direction of the substantially convex cross section are aligned; A variable resistor characterized in that the relative distance between a pair of electrodes, a resistor, and a contact point changes in response to an external force. (3) A pair of electrodes and a resistor are provided on one substrate, and a contact is placed inside a rubber cover that is formed to cover the pair of electrodes and resistor together with the one substrate and deforms in response to external force. The variable resistor according to claim 1 or 2, further comprising a variable resistor. (4) The variable resistor according to any one of claims (1) to (3), characterized in that all parts of the pair of electrodes that are in contact with the contact portions of the contacts are covered with a resistor. (5) Only the sides of the pair of electrodes that are close to each other are covered by the resistor, and the length between the ends of the substantially convex cross section of the contact portion of the contact is not covered by the resistor of the pair of electrodes. The variable resistor according to any one of claims 1 to 3, characterized in that the distance between the parts is greater than or equal to the distance between the parts. (6) The variable resistor according to any one of claims (1) to (5), characterized in that flat surfaces are provided at both ends in the direction of the substantially convex cross section of the contact portion of the contact. (7) A sensor comprising the variable resistor according to any one of claims (1) to (6). (8) A pair of electrodes are arranged on a first substrate at a predetermined distance from each other, and a planar resistor is arranged between the pair of electrodes, and on a flexible second substrate. Attach a contact made of conductive rubber and having a contact portion with at least one substantially convex cross section, and connect the wide surface of the resistor so that the direction connecting the pair of electrodes and the direction of the generally convex cross section match. A sensor characterized in that first and second substrates are combined so that the contact portions of the contacts face each other.