JPH09223607A - Pressure-sensitive electronic components - Google Patents

Abstract

(57) [PROBLEMS] To provide a pressure-sensitive electronic component that can be easily manufactured, can have a long pressing stroke of a key top, and can easily perform fine adjustment of a resistance value. SOLUTION: The pressure-sensitive resistance film 23 that reduces the resistance value in the thickness direction by pressing in the thickness direction, two electrode patterns 21 formed on the lower surface of the pressure-sensitive resistance film 23, and the pressure-sensitive resistance film 23 are formed. The pressure-sensitive film element 20 formed by stacking a conductive pattern 25 formed on the upper surface at a position facing the two electrode patterns 21 on the substrate 10, and the substrate 1
0 is a leaf spring-like elastic member 30 arranged on the pressure sensitive film element 20 so as to press on the conductive pattern 25 located right above the two electrode patterns 21, and a key for pressing the elastic member 30. And a top 40. By pressing the key top 40, the pressure-sensitive resistance film 23 of the pressure-sensitive film element 20 is elastically pressed by the elastic force of the elastic member 30 to reduce the resistance value in the thickness direction, and the resistance between the two electrode patterns 21 is reduced. Change the value.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a pressure-sensitive electronic component.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 8, a pressure-sensitive resistance rubber sheet 81, which is pressed in the thickness direction to reduce the resistance value in the thickness direction, is provided on a key top 8 via a conductive pattern 89.
7, the substrate 85 having the two electrode patterns 83, 83 is disposed directly below the pressure-sensitive resistance rubber sheet 81, and the key top 87 is pushed down to move the pressure-sensitive resistance rubber sheet 81 to the two pressure-sensitive resistance rubber sheets 81. Electrode patterns 83, 8
3 is a pressure-sensitive variable resistor having a structure in which the resistance value between the two electrode patterns 83, 83 is changed by the resistance value in the thickness direction of the pressure-sensitive resistance rubber sheet 81 that is pressed against 3 at the same time. .

Conventionally, as shown in FIG. 9, an elastic conductive rubber 93 having a pressure sensitive resistance film 91 applied to the lower surface thereof to reduce the resistance value in the thickness direction by pressing the elastic conductive rubber 93 on the lower surface of the key top 95. A substrate 99 having two electrode patterns 97, 97 mounted directly under the pressure-sensitive resistance film 91.
The pressure-sensitive resistive film 91 is pressed against the two electrode patterns 97, 97 at the same time by pressing the key top 95, and the resistance value in the thickness direction of the pressure-sensitive resistive film 91 is changed by the pressing force. The two electrode patterns 9
There is a pressure-sensitive variable resistor having a structure in which the resistance value between 7, 97 is changed.

[0004]

However, in these conventional pressure sensitive variable resistors, in addition to providing the electrode patterns 83, 83 (97, 97) on the substrate 85 (99), the key top 87 (95) side is provided. In addition, the pressure-sensitive resistance rubber sheet 81 and the conductive pattern 89 (the pressure-sensitive resistance film 91 and the elastic conductive rubber 93) have to be provided, and the manufacturing thereof is complicated.

In the conventional pressure sensitive variable resistor, the stroke when the key top 87 (95) is pressed is obtained by the amount of deflection of the pressure sensitive resistance rubber sheet 81 or the elastic conductive rubber 93. The pressing stroke obtained by this is short and it is difficult to finely adjust the resistance value, and the pressing force of the key top 87 (95) for bending the rubber material is also considerably large, so the operation feeling as a variable resistor is poor. There was a problem.

Further, in the case of the conventional example shown in FIG. 8, there is a problem that the pressure-sensitive resistance rubber sheet 81 used is expensive.

The present invention has been made in view of the above points, and an object thereof is to provide a pressure-sensitive electronic component which can be easily manufactured, a pressing stroke of a key top can be long, and a fine adjustment of a resistance value can be easily performed. To provide.

[0008]

In order to solve the above-mentioned problems, the present invention provides a pressure-sensitive resistance film which reduces the resistance value in the thickness direction by pressing in the thickness direction, and both surfaces of the pressure-sensitive resistance film or A pressure-sensitive film element that has at least two electrode patterns formed on one of the surfaces, and changes the resistance value between the two electrode patterns when the pressure-sensitive resistance film is pressed in the thickness direction. A pressure-sensitive film element, a base material, and a resilient member disposed directly on the pressure-sensitive film element formed portion of the base material or indirectly via another pressing member, By pressing the elastic member, the pressure-sensitive film element is elastically pressed by the elastic force of the elastic member.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic side sectional view showing a pressure-sensitive variable resistor according to an embodiment of the present invention. As shown in the figure, in the case of this embodiment, the pressure sensitive film element 20 is formed on the substrate 10, and the elastic member 30 and the key top (pressing body) 40 are arranged thereon, and further the elastic member 30. The key top 40 is surrounded by a case 50. Hereinafter, each component will be described.

FIG. 2 shows the pressure sensitive film element 2 of the substrate 10.
It is a figure which shows the part which formed 0, (a) of this figure is an enlarged plan view of an essential part, (b) is a sectional view taken along the line AA of (a) of the figure.

As shown in the figure, the pressure-sensitive film element 20 is
Two circular electrode patterns 21 on the insulating substrate 10,
21 is formed, and a pressure sensitive resistance film 23 is formed so as to cover both electrode patterns 21 and 21. Further, the pressure sensitive resistance film 2 is formed.
One conductive pattern 25 is formed at a position on the electrode 3 facing the two electrode patterns 21, 21.

The electrode patterns 21 and 21 are formed by screen-printing silver paste, and the circuit patterns 22 and 22 are drawn out from one end thereof. The thickness of the electrode patterns 21 and 21 is 10 μm in this embodiment.

Next, the pressure sensitive resistance film 23 is formed by printing a pressure sensitive material having a function of reducing the resistance value in the thickness direction by pressing in the thickness direction. The thickness of the pressure sensitive resistance film 23 is 40 to 100 μm in this embodiment.
m.

In the pressure-sensitive resistance film 23 according to this embodiment,
An anisotropic pressure-sensitive resistance film whose resistance value changed only in the pressing direction and remained in the insulating state in the other directions was used. As the material of the pressure-sensitive resistance film 23, an elastic material mixed with conductive powder is used. Specifically, in this embodiment, silicon rubber is used as the elastic material, carbon powder is used as the conductive powder, and 1 part by weight of carbon powder is mixed with 0.2 to 2 parts by weight of silicon rubber. It is dissolved in a solvent such as the high boiling point solvent. As the carbon powder, granulated carbon black having an average particle size of 1 to 20 μm is used.

The elastic material is not limited to silicone rubber, but other various rubber materials (eg, butadiene rubber, acrylonitrile / butadiene / styrene rubber, etc.) or thermoplastic elastomers (eg, styrene-based thermoplastic elastomer, olefin-based material). A thermoplastic elastomer or the like), a vinyl chloride / vinyl acetate resin material, or a material having various elasticity such as polyethylene can be used.

As the material of the conductive powder, in addition to granulated carbon black, spherical graphite, beaded graphite, scaly graphite,
Flake graphite, earth graphite and the like can be used, and a mixture thereof may be used. Other conductive metal powders may also be used.

Next, the conductive pattern 25 is formed by screen-printing a silver paste. The thickness of the conductive pattern 25 is 10 μm in this embodiment.
And

Next, FIG. 3 is an enlarged perspective view showing the elastic member 30. As shown in the figure, the elastic member 30 is formed by bending a conductive metal plate having elasticity into a substantially V shape. More specifically,
The angle between the lower surface 31 and the upper surface 33 is set to about 30 to 40 so that the upper surface 33 covers the lower surface 31.

In addition, in the vicinity of one end of the lower surface 31, two pressing protrusions 3 projecting downward in a substantially hemispherical shape.
5, 35 (see FIG. 1) are provided. In the pressing protrusions 35, 35, the elastic member 30 is the pressure-sensitive film element 20.
When disposed above, they are provided so as to be located directly above the two electrode patterns 21 and 21 shown in FIG.

On the other hand, one end portion of the upper surface 33 is provided with a pressure sliding contact portion 37 by being processed so as to be gently curved downward.

Returning to FIG. 1, the key top 40 is made of synthetic resin and has a collar portion 41 provided on the outer periphery of the lower end thereof.

The case 50 is provided with a through hole 51 through which the key top 40 is inserted, and a pressing projection accommodating portion 53 for positioning the pressing projection 35 of the elastic member 30 near the center of the lower surface. Is provided.

At the center of the case 50, there is provided a stopper portion 55 extending from the front side to the back side of the paper of FIG.

To assemble this pressure sensitive variable resistor, as shown in FIG. 1, a case 50 accommodating the elastic member 30 and the key top 40 is mounted on the substrate 10, and the substrate 10 is fixed to the substrate 10 by a fixing means (not shown). This is done by fixing the cases 50 together.

At this time, the pressing protrusion 35 of the elastic member 30
Is located inside the pressing projection housing portion 53 of the case 50, and the pressing sliding contact portion 37 of the elastic member 30 is in elastic contact with the center of the lower surface of the key top 40.

When the key top 40 is pushed down, the resilient member 30 bends and the pressing sliding contact portion 37 descends, and the resilient member 3 is pushed by a force corresponding to the amount of depression of the key top 40.
The two pressing protrusions 35, 35 of 0 simultaneously press the conductive patterns 25 directly above the two electrode patterns 21, 21 of the pressure sensitive film element 20, respectively.

As a result, the pressure sensitive resistance film 2 shown in FIG.
3 has a resistance value in the thickness direction of the two pressing protrusions 35,
It becomes smaller only in the portion pressed by 35.
That is, the two electrode patterns 21 and 21 and the conductive pattern 2
The resistance value between 5 becomes smaller according to the pressing force. Since the conductive pattern 25 is a single conductive film, the resistance value between the electrode patterns 21 and 21 via the conductive pattern 25 eventually decreases according to the pressing force.

By the way, according to this embodiment, since the leaf spring-shaped elastic member 30 is interposed between the pressure sensitive film element 20 and the key top 40, the pressure sensitive to the change of the pressing stroke of the key top 40. The elastic force applied to the membrane element 20 does not change rapidly, and the resistance value can be finely adjusted by that amount, and the pressing stroke can be lengthened.

Further, in the present embodiment, the pressure sensitive film element 2
Since 0 can be formed on only one substrate 10 and only the elastic member and the key top 40 need to be arranged thereon, the manufacturing and assembling work can be easily performed.

In this embodiment, the elastic member 30 is used.
Is made of a conductive metal plate, the elastic member 30 itself has the function of the conductive pattern 25, and thus the conductive pattern 25 is not always necessary.

That is, when the elastic member 30 is a conductive member, as shown in FIG. 4, two electrode patterns 21-2 and 21-2 are formed on the substrate 10-2, and a pressure sensitive material is formed thereon. It is also possible to only form the resistance film 23-2.

By the way, in the embodiment shown in FIGS. 1 to 3, the elastic member 30 is bent so that the angle between the upper and lower surfaces 31, 33 is about 30 to 40 °. When housed in the case 50, the lower surface 31 is made substantially parallel to the surface of the substrate 10 as shown in FIG.

Since the pressing direction of the key top 40 is substantially perpendicular to the surface 31, the key top 4
The surface 31 does not shift to the left or right on the substrate 10 with respect to the vertical movement of 0, and is held at a fixed position. It slides on the lower surface while being pressed.

For this reason, when the elastic member 30 having this shape is used, it is a leaf spring bent in a dogleg shape,
The positions of the pressing protrusions 35, 35 elastically contacting the pressure sensitive film element 20 do not shift due to the vertical movement of the key top 40,
Therefore, the surface of the pressure sensitive film element 20 is less likely to be worn.

In this embodiment, since the stopper portion 55 is provided in the case 50, when the key top 40 is pushed in, the lower surface of the push-sliding contact portion 37 of the elastic member 30 comes into contact therewith, and The descent of the key top 40 is stopped.

Contrary to the pressure sensitive film element 20 (see FIG. 2) used in the above-described embodiment, as shown in FIG.
Even if the conductive pattern 25-3 is formed on 0-3, the pressure sensitive resistance film 23-3 is formed thereon, and the two electrode patterns 21-3 and 21-3 are formed thereon, The same function as the pressure sensitive film element 20 shown in FIG. 2 is exhibited. That is, by pressing on the two electrode patterns 21-3, 21-3, the resistance value between the two electrode patterns 21-3, 21-3 changes.
An insulating member is used as the elastic member 30 for pressing the pressure sensitive film element 20-3. If an insulating film is formed by screen printing so as to cover both of the electrode patterns 21-3 and 21-3, a conductive material may be used as the elastic member 30.

FIG. 6 is a schematic side sectional view showing a pressure sensitive variable resistor according to another embodiment of the present invention. In the case of this embodiment, the pressure sensitive film element 20-4 is formed on the substrate 10-4, and the elastic member 3 is formed on the pressure sensitive film element 20-4 via another pressing member 60-4.
0-4 and the key top 40-4 are arranged, and these members are housed in the case 50-4.

Here, the substrate 10-4 and the pressure-sensitive film element 20-4 are used.
1 has the same structure as that shown in FIG. 1, the description thereof will be omitted.

The elastic member 30-4 is composed of a coil spring. On the other hand, the pressing member 60-4 is made of a rod-shaped synthetic resin material, the lower end of which is in contact with the conductive pattern 25-4, and the two electrode patterns 21-4 and 21-4 (one on the front side in the figure). (Only shown) is pressed directly above.

The hole 43 provided in the key top 40-4
-4 accommodates the elastic member 30-4, and the upper end of the pressing member 60-4 is inserted below the elastic member 30-4.

When the key top 40-4 is pushed down, the elastic member 30-4 bends and the pressing member 60-4 is pushed downward, and the key top 40-4 is pushed with a force corresponding to the pushing amount. The lower end of the member 60-4 is the conductive pattern 2
Repress 5-4. As a result, similarly to the above-described embodiment, the resistance value between the two electrode patterns 21-4 and 21-4 becomes smaller according to the amount of depression of the key top 40-4. Although the pressure-sensitive element 20-4 of this embodiment is constructed as shown in FIG. 2, it may be constructed as shown in FIG.

Next, FIG. 7 is a diagram showing a pressure-sensitive film element 20-5 having another structure used in the present invention. FIG. 7 (a) is an enlarged plan view of the main part, and FIG. 7 (b) is the same figure ( It is DD sectional drawing of a).

The pressure sensitive film element 20-5 is composed of the substrate 10-5.
One circular electrode pattern 21-5 is formed on the pressure sensitive resistance film 23- so as to cover the electrode pattern 21-5.
5 is formed, and another circular electrode pattern 27-5 is formed on the pressure-sensitive resistance film 23-5 at a position facing the electrode pattern 21-5.

Here, both electrode patterns 21-5 and 27-5
From, the circuit patterns 22-5 and 28-5 are drawn out, respectively.

If the electrode pattern 27-5 on the upper side of the pressure sensitive film element 20-5 thus constructed is pressed by the elastic member or the pressing member as shown in each of the above embodiments (in the case of this embodiment, It is sufficient to press only one place), and the resistance value between the electrode patterns 27-5 and 21-5 changes according to the pressing force. This pressure sensitive film element 20-5 is also a substrate 10-5.
Can only be formed on top.

By the way, the base material for forming the pressure-sensitive film element may be a hard insulating substrate, a film-shaped substrate, an insulating film formed on a metal plate, or a mold case itself. It may be.

If an insulating protective film is formed by screen printing on the pressure-sensitive film element of the embodiments of FIGS. 2, 5 and 7, the pressure-sensitive film element is protected from mechanical abrasion.

In each of the above embodiments, the pressure-sensitive electronic component according to the present invention is used as a variable resistor, but the present invention can be configured as a push-type switch. That is, since the pressure-sensitive resistance film has an action of changing its resistance value by the pressing force in the thickness direction, the resistance value at the time of pressing is adjusted by adjusting the material, thickness and elastic force of the pressure-sensitive resistance film. It is also possible to construct a switch by constructing the switch so that it becomes abruptly smaller.

[0049]

As described in detail above, the present invention has the following excellent effects. Since the pressure-sensitive film element used in the present invention can be formed by printing or the like on only one base material, it suffices to dispose the elastic member on the base material, which facilitates the manufacturing and assembling work. I can do it.

Further, according to the present invention, the pressure sensitive film element can be formed only on one substrate as shown in the above effect, and any constituent element of the pressure sensitive film element is provided on the elastic member side as in the prior art. Since there is no need, it is possible to freely design the elastic member.
That is, for example, a leaf spring or a coil spring suitable for improving the operation feeling can be used as it is as the elastic member.

Further, according to the present invention, not only the resistance value can be finely adjusted, but also the pressing stroke can be lengthened.

[Brief description of drawings]

FIG. 1 is a schematic side sectional view showing a pressure sensitive variable resistor according to an embodiment of the present invention.

2A and 2B are diagrams showing a portion of a substrate 10 on which a pressure sensitive film element 20 is formed. FIG. 2A is an enlarged plan view of an essential part, and FIG.
FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is an enlarged perspective view showing a resilient member 30.

FIG. 4 is a pressure-sensitive film element 20-2 having another structure used in the present invention.
FIG. 3A is an enlarged plan view of a main part, and FIG. 3B is a sectional view taken along line BB of FIG.

FIG. 5 is a pressure-sensitive film element 20-3 having another structure used in the present invention.
FIG. 7A is an enlarged plan view of a main part, and FIG. 7B is a sectional view taken along line CC of FIG.

FIG. 6 is a schematic side sectional view showing a pressure-sensitive variable resistor according to another embodiment of the present invention.

FIG. 7 is a pressure-sensitive film element 20-5 having another structure used in the present invention.
FIG. 4A is an enlarged plan view of a main part, and FIG. 3B is a sectional view taken along line D-D of FIG.

FIG. 8 is a diagram showing a conventional example.

FIG. 9 is a diagram showing a conventional example.

[Explanation of symbols]

 10 Substrate (Base Material) 20 Pressure Sensitive Membrane Element 21, 21 Electrode Pattern 23 Pressure Sensitive Resistive Film 25 Conductive Pattern 30 Elastic Member 40 Key Top (Pressing Body) 60-4 Other Pressing Member

Claims (4)

[Claims] 1. A pressure-sensitive resistance film that reduces a resistance value in the thickness direction by pressing in the thickness direction, and at least two electrode patterns formed on both surfaces or one surface of the pressure-sensitive resistance film. A pressure-sensitive film element that changes the resistance value between the two electrode patterns when the pressure-sensitive resistance film is pressed in the thickness direction, a base material that forms the pressure-sensitive film element, and the base. A resilient member disposed directly on the pressure-sensitive film element-forming portion of the material or indirectly via another pressing member, and by pressing the resilient member, the pressure-sensitive film element is A pressure-sensitive electronic component that is elastically pressed by the elastic force of the elastic member. 2. The pressure-sensitive film element includes the pressure-sensitive resistance film,
The base material includes a plurality of electrode patterns formed on one surface of the pressure-sensitive resistance film, and a conductive pattern formed on the other surface of the pressure-sensitive resistance film at a position facing the plurality of electrode patterns. The pressure-sensitive electronic component according to claim 1, wherein the pressure-sensitive electronic component is formed by stacking layers on the elastic member, and the elastic member is arranged to press either the plurality of electrode patterns or the conductive pattern. . 3. The pressure-sensitive film element includes the pressure-sensitive resistance film,
A plurality of electrode patterns formed on the lower surface of the pressure-sensitive resistive film are laminated on the base material, while the elastic member is a conductor and directly on the pressure-sensitive film element. 2. The elastic member is further arranged so as to press on the pressure sensitive film element located on each of the plurality of electrode patterns.
The pressure-sensitive electronic component described. 4. The pressure-sensitive film element includes the pressure-sensitive resistance film,
At least two electrode patterns formed so as to face each other on both sides of the pressure-sensitive resistive film are laminated on the base material, and at least one elastic member for pressing the pressure-sensitive film element is used. The pressure-sensitive electronic component according to claim 1, wherein the pressure-sensitive electronic component is arranged so as to press the two electrode patterns.