JP7222729B2 - pressure sensitive switch - Google Patents

Description

The present invention relates to a pressure sensitive switch and its manufacturing method.

2. Description of the Related Art Pressure-sensitive switches are used as operation switches for mobile communication devices such as smartphones and electronic devices such as pen tablet devices. A pressure-sensitive switch has a dielectric member inside and a conductive member arranged adjacent to the dielectric part with a gap therebetween. It is a switch that detects changes in capacitance.

Since the capacitance when the dielectric member and the conductive member are in contact varies depending on the surface condition, the pressure sensitive switch is required to be dustproof and waterproof.

Patent Document 1 discloses a dielectric, a first electrode attached to one surface of the dielectric, a flexible second electrode disposed on the other surface, a second electrode, and others. A variable capacitor is disclosed having a spacer spaced between the faces of the . The variable capacitor further has a pressing body that changes the distance between the second electrode and the other surface, and functions as a pressure sensitive switch.

JP-A-05-275283

However, the variable capacitor described in Patent Document 1 does not have dustproof and waterproof properties, and the capacitance between the dielectric and the second electrode varies greatly depending on the surface state of the contact surface, or Undetectable.

SUMMARY OF THE INVENTION An object of the present invention is to provide a pressure-sensitive switch that is easy to manufacture and excellent in dust resistance and water resistance.

A pressure sensitive switch according to the present invention includes a substrate, a conductive first land arranged on the substrate, a conductive second land arranged on the substrate so as to be insulated from the first land, and a second land. The dielectric member is arranged above the dielectric member so that the distance between the dielectric member arranged on one land and the dielectric member when it is not pressed from above is a predetermined separation distance, and is separated from the dielectric member. a flexible conductive member whose distance to the dielectric member becomes shorter than the separation distance when pressed from the substrate; a connecting member that electrically connects the second land and the conductive member; an outer frame member arranged to form an accommodating portion for accommodating the first land, the second land, the dielectric member and the conductive member; and the first land and the second land arranged on the outer frame member and accommodated in the accommodating portion. a sealing sheet for sealing the land, the dielectric member and the conductive member; a first electrode electrically connected to the first land; and a second electrode electrically connected to the second land. Characterized by

In the pressure-sensitive switch according to the present invention, the conductive member is preferably an upwardly convex conductive spring.

A pressure-sensitive switch according to the present invention has a frame-like planar shape whose height is equal to the separation distance, and is arranged between the dielectric member and the conductive member so that the dielectric member and the conductive member are separated by the separation distance. It is preferred to further include spaced-apart spacer frame members.

The pressure-sensitive switch according to the present invention preferably further has an upper frame member between the outer frame member and the sealing sheet.

In the pressure-sensitive switch according to the present invention, the outer frame member is formed with a through hole extending through the upper surface and the lower surface, and the connection member penetrates so that the upper end is in contact with the conductive member and the lower end is in contact with the second land. It is preferably inserted into the hole.

Preferably, in the pressure-sensitive switch according to the present invention, the connection member is attached along the inner surface of the outer frame member.

In the pressure-sensitive switch according to the present invention, the connection member accommodates the substrate, the first land, the second land, the dielectric member, the conductive member, the sealing sheet, and the outer frame member, and the conductive member along the outer surface of the outer frame member. It is preferably a flexible storage case.

A pressure-sensitive switch according to the present invention includes a bottom portion having a downwardly convex shape, a bar-shaped shaft portion extending upward from the bottom portion, and a side surface of the shaft portion extending in a direction orthogonal to the extending direction of the shaft portion. A plunger having a flange and arranged so that the bottom portion is in contact with the sealing sheet, a top surface having an opening through which the shaft can pass, and a side surface extending from the end of the top surface in a direction perpendicular to the top surface. and a plunger case, wherein the flange is preferably located between the top surface and the sealing sheet.

The pressure-sensitive switch according to the present invention corresponds to a shape in which a plurality of substrates are connected to a collective substrate having a shape in which a plurality of substrates on which first lands and second lands insulated from the first lands are arranged are connected. , a collective outer frame member having a shape in which a plurality of outer frame members constituting a pressure-sensitive switch are connected, a dielectric member is disposed on each first land, and each second land and the conductive member are electrically connected to each other; A connection member to be connected is arranged, a conductive member is arranged separately from each dielectric member, each conductive member is covered, a collective sealing sheet is arranged on the collective outer frame member, and collectively sealed on the collective outer frame member. By heating the collective substrate on which the stop sheet is arranged, the collective substrate and collective sealing sheet are adhered to the outer frame member, and the second land, the electric member and the connection member are adhered to the collective outer frame member. The method includes cutting the collective substrate on which the collective sealing sheet is arranged.

According to the present invention, it is possible to provide a pressure-sensitive switch that is easy to manufacture and is excellent in dustproofness and waterproofness.

1A is a perspective view of a pressure-sensitive switch 1, and FIG. 1B is an exploded perspective view of the pressure-sensitive switch 1. FIG. , (c) is a sectional view taken along line AA' shown in (a). FIG. 4A is a cross-sectional view illustrating a state in which the pressure-sensitive switch according to the first embodiment changes when it is pressed from above; FIG. ) is a sectional view when the pressure-sensitive switch 1 is pressed from above. It is a figure which shows an example of the manufacturing method of a pressure-sensitive switch. FIG. 10 is a diagram for explaining the outline of the configuration of an example of the pressure-sensitive switch of the second embodiment, (a) is 3 perspective views of the pressure-sensitive switch, (b) is an exploded perspective view of the pressure-sensitive switch 3, (c) is a cross-sectional view taken along line AA' shown in (a). FIG. 10 is a cross-sectional view for explaining a state in which the pressure-sensitive switch of the second embodiment changes when pressed from above; (a) is a sectional view when the pressure-sensitive switch 3 is not pressed from above, and (b) is a sectional view when the pressure-sensitive switch 3 is pressed from above. FIG. 10 is a diagram for explaining the outline of the configuration of an example of the pressure-sensitive switch of the third embodiment, (a) is a perspective view of the pressure-sensitive switch 4, (b) is an exploded perspective view of the pressure-sensitive switch 4, (c) is a cross-sectional view taken along line AA' shown in (a). FIG. 11 is a cross-sectional view illustrating a state in which the pressure-sensitive switch according to the third embodiment changes when pressed from above; (a) is a sectional view when the pressure-sensitive switch 4 is not pressed from above, and (b) is a sectional view when the pressure-sensitive switch 4 is pressed from above. FIG. 10A is a cross-sectional view showing an example of a pressure-sensitive switch 5 of Modification 1, and FIG. 8B is an outer surface of an outer frame member of Modification 2. FIG. FIG. 4 is a cross-sectional view showing an example with an inner surface along the . 1 shows an example of a voltage detection system for detecting the voltage between the first electrode and the second electrode of the pressure-sensitive switch of the present invention corresponding to pressing from above, and (a) shows a pressure-sensitive capacitor equivalent to the pressure-sensitive switch. , (b) shows a block diagram of the voltage detection system.

A pressure-sensitive switch according to one aspect of the present disclosure will be described below with reference to the drawings. However, it should be noted that the technical scope of the present disclosure is not limited to those embodiments, but extends to the invention described in the claims and equivalents thereof. In the following description and drawings, components having the same functional configuration are denoted by the same reference numerals, thereby omitting redundant description.

[Overview of Configuration of Pressure-Sensitive Switch of First Embodiment]
1A and 1B are diagrams for explaining an outline of the configuration of an example of a pressure-sensitive switch according to a first embodiment, in which FIG. 1A is a perspective view of the pressure-sensitive switch, and FIG. 1B is an exploded perspective view of the pressure-sensitive switch. , and (c) is a sectional view taken along the line AA' shown in (a).

The pressure-sensitive switch 1 includes a substrate 10, a first land 11, a second land 12, an outer frame member 13, a dielectric member 14, a spacer frame member 15, a connection member 16, a conductive member 17, an upper frame member 18, and a sealing sheet. 19. In the manufacturing process of the pressure-sensitive switch 1, for example, a thermosetting resin adhesive is used to bond each member, so it is preferable that the members constituting the pressure-sensitive switch 1 have heat resistance that can withstand reflow.

The substrate 10 is a flat member made of, for example, an insulating resin material, and has a rectangular surface. A conductive first land 11 is arranged on the substrate 10 . The first land 11 is, for example, a rectangular flat conductor, is arranged in the center of the upper surface of the substrate 10, and the dielectric member 14 is placed on the upper surface. A conductive second land 12 is arranged on the outer peripheral side of the first land 11 so as to be insulated from the first land 11 . The second land 12 is, for example, a circular flat conductor. The second land 12 may be, for example, rectangular instead of circular, or may be a rectangular frame-shaped flat plate conductor surrounding the first land 11, or a plurality of flat plate conductors may be provided. The first land 11 and the second land 12 are formed of a conductive material such as conductive plastic and arranged on the surface of the substrate 10 . The first land 11 and the second land 12 may be formed by etching a substrate on which metal foil such as copper foil is deposited.

The outer frame member 13 is arranged on the upper surface of the substrate 10 so as to surround the first land 11 and cover the second land 12 . The outer frame member 13 is, for example, a rectangular frame-shaped member made of a resin material so as to match the outer circumference of the substrate 10 , and is adhered to the upper surface of the substrate 10 via an adhesive or an adhesive member such as an adhesive sheet 20 . be. The adhesive or bonding member is preferably made of a thermosetting resin. This is because each member can be heated and bonded after being arranged.

By arranging the outer frame member 13 on the upper surface of the substrate 10, the outer frame member 13 surrounds the first land 11 and accommodates the second land 12, the dielectric member 14, the spacer frame member 15, and the conductive member 17. 131 is formed.

The outer frame member 13 has through holes 132 and notch guides 133 . The through hole 132 is a hole for inserting the connection member 16 for electrically connecting the second land and the conductive member 17, and is provided so as to pass from the upper surface to the lower surface of the outer frame member 13. As shown in FIG. The through hole 132 is provided such that the lower surface side opening of the through hole 132 overlaps at least a portion of the second land 12 . The shape of the opening of the through-hole 132 may be, for example, a rectangular shape other than a circle as long as it corresponds to the shape of the connection member.

The adhesive sheet 20 for bonding the outer frame member 13 to the upper surface of the substrate 10 has openings at portions corresponding to portions where the lower surface side openings of the through holes 132 and the second lands 12 overlap. This is for electrically connecting the second land 12 and the conductive member 17 . Similarly, when an adhesive such as a thermosetting resin adhesive is applied and the outer frame member 13 is arranged on the upper surface of the substrate 10, it corresponds to the portion where the lower surface side opening of the through hole 132 and the second land 12 overlap. No adhesive is applied to the

The notch guide 133 is a groove that fits the projecting portion 172 of the conductive member 17 and guides the projecting portion 172 to the opening of the through hole 132 on the upper surface of the outer frame member 13 .

The dielectric member 14 is a plate-shaped member, and is a dielectric having a dielectric constant of 1,000 or more and a thickness of 0.2 mm or more, which is arranged on the first land 11, for example. The dielectric is, for example, barium titanate. The dielectric member 14 has the effect of increasing the sensitivity of the capacitance change due to the change in the distance of the gap between the dielectric member 14 and the conductive member 17 when the pressure sensitive switch is pressed from above. The dielectric member 14 is adhered to the upper surface of the first land 11 via an adhesive agent or adhesive member (not shown).

The spacer frame member 15 is a flat plate-like frame member having insulating properties. to form a void. The spacer frame member 15 is, for example, an insulating resin with a thickness of 0.005 mm or more and 0.5 mm or less. The spacer frame member 15 is adhered to the upper surface of the dielectric member 14 via an adhesive agent or adhesive member (not shown).

The connection member 16 is inserted into the through-hole 132 and electrically connects the second land 12 and the conductive member 17, and is made of, for example, a cylindrical conductive resin. As an example, the connecting member 16 may have a cuboid shape or a substantially conical shape. Alternatively, the connection member 16 may be formed by injecting, for example, a conductive thermosetting resin paste or solder paste into the through-hole 132 and arranging the conductive member 17, followed by heat treatment. Electrical connection between the second land 12 and the conductive member 17 can be easily ensured.

The conductive member 17 has a body portion 171 and a projecting portion 172, and is made of, for example, a flat plate-like conductive rubber having flexibility. The thickness of the conductive member 17 is 0.1 mm or more and 1.0 mm or less. The main body portion 171 is arranged on the spacer frame member 15 , and the projecting portion 172 extends from the main body portion 171 toward the outer frame member 13 , engages with the notch guide 133 , and extends through the through hole on the upper surface of the outer frame member 13 . 132 opening to electrically connect with the connecting member 16 .

The conductive member 17 is spaced above the dielectric member 14 so that the distance from the dielectric member 14 when the pressure sensitive switch 1 is not pressed down from above is a predetermined separation distance. As the conductive member 17 is pressed from above, the distance between it and the dielectric member 14 becomes shorter than the predetermined separation distance, and the capacitance between the dielectric member 14 and the conductive member 17 changes.

The upper frame member 18 is, for example, a rectangular frame-shaped member made of a resin material so as to match the outer periphery of the substrate 10, and is adhered to the upper surface of the outer frame member 13 via an adhesive or adhesive member (not shown). be. This is to strengthen the fixation of the projecting portion 172 that fits into the notch guide 133 . Incidentally, the upper frame member 18 may be provided with a notch guide on the lower surface side in place of the notch guide 133 of the outer frame member 13 or similarly. Note that the upper frame member 18 may be omitted.

The sealing sheet 19 is adhered to the upper surface of the upper frame member 18 via an adhesive agent or adhesive member (not shown) so as to cover the conductive member 17 . The sealing sheet 19 is made of, for example, a polyimide sheet that is waterproof and flexible. By using the sealing sheet 19, it is possible to seal the first land 11, the second land 12, the dielectric member 14, the spacer frame member 15, and the conductive member 17 accommodated in the accommodating portion 131. The dustproof and waterproof properties of the switch 1 are ensured. Furthermore, it is preferable that the adhesive agent or adhesive member for bonding each member has dust resistance and water resistance.

FIG. 1(c) is a sectional view taken along line AA' shown in FIG. 1(a). By arranging the outer frame member 13 on the upper surface of the substrate 10 , an accommodation portion 131 is formed that surrounds the first land 11 and accommodates the second land 12 , the dielectric member 14 , the spacer frame member 15 and the conductive member 17 .

A first electrode 102 connected to the first land 11 through a via hole 101 and a second electrode 104 connected to the second land 12 through a via hole 103 are formed on the lower surface of the substrate 10 . The pressure sensitive switch 1 is connected to an external device via the first electrode 102 and the second electrode 104 . A predetermined voltage is applied between the first electrode and the second electrode from an external device. The second electrode outputs a voltage between the first electrode and the first electrode that varies as the distance between the dielectric member 14 and the conductive member 17 becomes shorter than the predetermined separation distance.

FIG. 2 is a cross-sectional view illustrating how the pressure-sensitive switch according to the first embodiment changes when pressed from above. (a) is a sectional view when the pressure-sensitive switch 1 is not pressed from above, and (b) is a sectional view when the pressure-sensitive switch 1 is pressed from above.

When the pressure sensitive switch 1 is not depressed from above, the predetermined separation distance between the dielectric member 14 and the conductive member 17 is d. When the pressure-sensitive switch 1 is pressed from above the sealing sheet 19 by a pressing body 200 such as a finger or a pen made of non-dielectric resin, the sealing sheet 19 protrudes downward, and the main body portion 171 of the conductive member 17 is pressed. press down. Since the conductive member 17 is made of, for example, a flat plate-like conductive rubber having flexibility, the body portion 171 is curved downward. Since the main body portion 171 is curved downward, the distance between the dielectric member 14 and the conductive member 17 becomes d−Δd, which is shorter than the predetermined separation distance, and the capacitance between the dielectric member 14 and the conductive member 17 is reduced. changes.

[Overview of an example of a method for manufacturing a pressure-sensitive switch]
Taking the pressure-sensitive switch of the first embodiment as an example, a process for collectively manufacturing a plurality of pressure-sensitive switches according to the present invention will be described.

FIG. 3 is a diagram showing an example of a method of manufacturing a pressure-sensitive switch. (a) shows a collective outer frame member 23 in a shape in which a plurality of outer frame members are connected via a collective adhesive sheet 22 in a shape in which a plurality of adhesive sheets are connected on a collective substrate 21 in a shape in which a plurality of substrates are connected. FIG. 10 is a diagram showing the steps to be performed; (b) is a diagram showing a process of arranging dielectric members 14, spacer frame members 15, connecting members 16, and conductive members 17 in each box 24 formed by the collective substrate 21 and collective outer frame member 23. FIG. . (c) is a diagram showing a process in which a collective upper frame member 25 having a shape in which upper frame members are connected is arranged, and further a collective sealing sheet 26 having a shape in which a plurality of sealing sheets are connected is arranged. (d) is a diagram showing a step of cutting the aggregate substrate.

First, a single collective substrate 21 having a shape in which a plurality of substrates 10 of the pressure-sensitive switch 1, for example, a total of 6 substrates 10 of 2×3, are connected is prepared. A first land 11 and a second land 12 formed by, for example, pattern etching are arranged on the upper surface of each substrate 10 .

A collective adhesive sheet 22 is arranged on the upper surface of the collective substrate 21 . The collective adhesive sheet 22 is an adhesive sheet in which portions corresponding to the first land and the second land of each substrate 10 are opened. A collective outer frame member 23 is arranged on the collective adhesive sheet 22 . The collective outer frame member 23 is a collective outer frame member having a shape in which a plurality of outer frame members 13 are connected in the same arrangement as the substrates 10 of the collective substrate 21 . By arranging the collective board 21 and the collective outer frame member 23, a plurality of boxes 24, in this example, a total of 6 boxes 24 (2×3) are formed. Each box 24 corresponds to a housing portion 131 that surrounds the first land 11 and houses the second land 12 , the dielectric member 14 , the spacer frame member 15 and the conductive member 17 .

Then, within each box 24, the dielectric member 14, the spacer frame member 15, the connection member 16, and the conductive member 17 are placed respectively. The dielectric member 14 is arranged on the first land 11, and the spacer frame member 15 is arranged on the dielectric member 14 via, for example, a thermosetting resin adhesive or adhesive sheet. The connection member 16 is inserted into the through hole 132 . When the connection member 16 is, for example, a conductive thermosetting resin paste or solder paste, the paste is injected into the through holes 132 using a dispenser. The conductive member 17 is arranged so as to fit into the notch guide 133 .

Furthermore, a collective upper frame member 25 having a shape in which the upper frame members are connected is arranged, and a collective sealing sheet 26 having a shape in which a plurality of sealing sheets are connected is provided via, for example, a thermosetting resin adhesive or adhesive sheet. A collective pressure-sensitive switch 27 is arranged and connected to the pressure-sensitive switch 1 . Incidentally, when the pressure-sensitive switch 1 does not use the upper frame member, the collective upper frame member 25 is not arranged. The collective pressure-sensitive switch 27 is subjected to heat treatment for thermal curing of the adhesive or adhesive sheet and melting of the conductive thermosetting resin paste and solder paste used for the connection member 16 . After the heat treatment, the collective pressure-sensitive switch 27 becomes normal temperature, and then the collective pressure-sensitive switch 27 is cut off as shown by the broken line in FIG. It becomes pressure switch 1.

[Overview of Configuration of Pressure-Sensitive Switch of Second Embodiment]
In the pressure-sensitive switch of the first embodiment, pressing from above is performed on the sealing sheet. In the pressure-sensitive switch of the second embodiment, a plunger is provided on the sealing sheet, and the plunger is pushed down from above.

4A and 4B are diagrams for explaining an outline of the configuration of an example of the pressure-sensitive switch of the second embodiment, where (a) is a perspective view of the pressure-sensitive switch and (b) is an exploded perspective view of the pressure-sensitive switch. (c) is a cross-sectional view taken along the line AA' shown in (a).

The pressure-sensitive switch 3 includes a substrate 10, a first land 11, a second land 12, an outer frame member 13, a dielectric member 14, a spacer frame member 15, a connection member 16, a conductive member 17, an upper frame member 18, and a sealing sheet 19. , plunger 31 and plunger case 32 .

The substrate 10, the first land 11, the second land 12, the outer frame member 13, the dielectric member 14, the spacer frame member 15, the connection member 16, the conductive member 17, the upper frame member 18, and the sealing sheet 19 are described in the embodiment. Since it is the same as the pressure-sensitive switch 1 of No. 1, the description is omitted.

A plunger 31 is placed on the sealing sheet 19 . The plunger 31 includes a bottom portion 311 having a convex shape in contact with the sealing sheet 19 , a rod-shaped shaft portion 312 extending upward from the bottom portion 311 , and a side surface of the shaft portion 312 perpendicular to the extending direction of the shaft portion 312 . and a flange 313 extending in the direction of The plunger 31 is formed by, for example, a resin mold made of polyphthalamide.

The plunger case 32 is, for example, a rectangular frame-shaped case made of a resin material to match the outer periphery of the substrate 10, and is adhered to the upper surface of the sealing sheet 19 via an adhesive or adhesive member (not shown). be. The plunger case 32 has an upper surface in which an opening 321 is formed, and a side surface extending from the end of the upper surface in a direction perpendicular to the upper surface, and a portion of the plunger 31 above the flange 313 protrudes from the opening 321, It houses the lower portion of plunger 31 including flange 313 .

The plunger 31 moves in a direction perpendicular to the substrate 10 when pressure is applied from above, and the pressure is transmitted to the sealing sheet 19 . By using the plunger 31, it is possible to detect subtle changes in pressure.

FIG. 5 is a cross-sectional view illustrating how the pressure-sensitive switch according to the second embodiment changes when pressed from above. (a) is a sectional view when the pressure-sensitive switch 3 is not pressed from above, and (b) is a sectional view when the pressure-sensitive switch 3 is pressed from above.

When the pressure sensitive switch 3 is not depressed from above, the predetermined separation distance between the dielectric member 14 and the conductive member 17 is d. In the pressure-sensitive switch 3, when the head of the plunger 31 is pushed by the pusher 200, the sealing sheet 19 in contact with the bottom 311 of the plunger 31 is pushed down from above. It becomes convex and pushes down the body portion 171 of the conductive member 17 . Since the conductive member 17 is made of, for example, a flat plate-like conductive rubber having flexibility, the body portion 171 is curved downward. Since the main body portion 171 is curved downward, the distance between the dielectric member 14 and the conductive member becomes d−Δd, which is shorter than the predetermined separation distance, and the electrostatic capacitance between the dielectric member 14 and the conductive member 17 becomes Change.

[Overview of Configuration of Pressure-Sensitive Switch of Third Embodiment]
The pressure-sensitive switches of the first and second embodiments use a flat plate-shaped conductive member. The pressure-sensitive switch of the second embodiment uses an upwardly convex conductive spring as a conductive member.

6A and 6B are diagrams for explaining an outline of the configuration of an example of the pressure-sensitive switch of the third embodiment, where (a) is a perspective view of the pressure-sensitive switch and (b) is an exploded perspective view of the pressure-sensitive switch. (c) is a cross-sectional view taken along the line AA' shown in (a).

The pressure sensitive switch 4 has a substrate 40 , a first land 41 , a second land 42 , an outer frame member 43 , a dielectric member 44 , a connection member 45 , a conductive member 46 and a sealing sheet 47 .

The substrate 40 is a flat member made of, for example, an insulating resin material, and has a rectangular surface. A conductive first land 41 is disposed on the substrate 40 . The first land 41 is, for example, a rectangular flat conductor, is arranged in the center of the upper surface of the substrate 40, and the dielectric member 44 is placed on the upper surface. A conductive second land 42 is arranged on the outer peripheral side of the first land 41 so as to be insulated from the first land 41 . The second land 42 is, for example, a circular flat conductor. The second land 42 may be, for example, a rectangular frame-shaped flat plate conductor surrounding the first land 41 . The first land 41 and the second land 42 are formed of a conductive material such as conductive plastic and arranged on the surface of the substrate 40 . The first land 41 and the second land 42 may be formed by etching a substrate on which metal foil such as copper foil is vapor-deposited.

The outer frame member 43 is arranged on the upper surface of the substrate 40 so as to surround the first land 41 and cover the second land 42 . The outer frame member 43 is, for example, a rectangular frame-shaped member made of a resin material so as to match the outer circumference of the substrate 40 , and is adhered to the upper surface of the substrate 40 via an adhesive or an adhesive member such as the adhesive sheet 20 . be.

By placing the outer frame member 43 on the upper surface of the substrate 40 , the outer frame member 43 surrounds the first land 41 and forms a housing portion 431 that houses the second land 42 , the dielectric member 44 and the conductive member 46 . .

The outer frame member 43 has a through-hole 432 and two opposed notches 433 and 434 formed by notching the inner surface of the outer frame member. The through-hole 432 is a hole for inserting the connecting member 45 for electrically connecting the second land 42 and the conductive member 46 , and the through-hole 432 is formed so as to pass from the upper surface of the notch 433 to the lower surface of the outer frame member 43 . is provided in The through hole 432 is provided such that the lower surface side opening of the through hole 432 overlaps at least a portion of the second land 42 . The opening shape of the through hole 432 may be rectangular, for example, other than circular. This is to accommodate the shape of the connecting member 45 .

Further, the adhesive sheet 48 for bonding the outer frame member 43 to the upper surface of the substrate 40 has openings at portions corresponding to portions where the lower surface side openings of the through holes 432 and the second lands overlap. This is for electrically connecting the second land and the conductive member 46 . Similarly, when the outer frame member 43 is adhered to the upper surface of the substrate 40 by applying an adhesive such as a thermosetting adhesive, the portion corresponding to the portion where the lower surface side opening of the through hole 432 and the second land 42 overlap is applied. No adhesive is applied to the

Two cutouts 433 and 434 are provided to cut out the inner surface of the outer frame member 43 and face each other in order to arrange the two ends of the conductive member 46 bridged over the dielectric member 44 . .

The dielectric member 44 is a plate-shaped member, and is a dielectric having a dielectric constant of 1,000 or more and a thickness of 0.2 mm or more, which is arranged on the first land 41, for example. The dielectric member 44 has a function of increasing the sensitivity of capacitance change due to a change in the distance of the gap between the dielectric member 44 and the conductive member 46 when the pressure sensitive switch 4 is pressed from above. The dielectric member 44 is adhered to the upper surface of the first land 41 via an adhesive agent or adhesive member (not shown).

The connection member 45 is inserted into the through-hole 432 and electrically connects the second land 42 and the conductive member 46, and is made of, for example, a cylindrical conductive resin. As an example, the connecting member 45 may be cuboidal. Alternatively, the connection member 45 may be formed by injecting, for example, a conductive thermosetting resin paste or solder paste into the through-hole 432 and arranging the conductive member 46, followed by heat treatment.

The conductive member 46 is an elastic conductive leaf spring member that can bend in response to being pressed from above, and is made of, for example, stainless steel. Also, the conductive member 46 may be a spring member made of a conductive resin material. The conductive member 46 has a body portion 461 having a curved spring shape and a protruding portion 462 extending from an end portion of the body portion 461 by bending toward the inside of the body portion. The conductive member 46 is arranged in the two notches 433 and 434 so as to protrude upward with respect to the dielectric member 44 .

The conductive member 46 is bridged over the dielectric member 44, and extends above the dielectric member 44 so that the distance between the dielectric member 44 and the dielectric member 44 is a predetermined separation distance when the pressure sensitive switch 4 is not pressed down from above. It is spaced apart from the member 44 to form an air gap spaced apart from the dielectric member 44 . When the pressure-sensitive switch 4 is pushed down from above, the capacitance between the first land 41 and the body portion 461 of the conductive member 46 changes due to the change in separation distance between the dielectric member 44 and the body portion 461 of the conductive member 46 .

The protruding portion 462 extends from the end portion of the main body portion 461 by bending toward the inner side of the main body portion and reaches the opening of the through hole 432 on the upper surface of the notch portion 433 , so that it is electrically connected to the connecting member 45 . .

The sealing sheet 47 is adhered to the upper surface of the outer frame member 43 via an adhesive agent or adhesive member (not shown) so as to cover the conductive member 46 . The sealing sheet 47 is formed of, for example, a polyimide sheet having waterproofness and flexibility. By using the sealing sheet 47, the first land 41, the second land 42, the dielectric member 44, and the conductive member 46 accommodated in the accommodating portion 431 can be sealed, and the pressure-sensitive switch 4 can be dust-proof. , waterproofness is ensured. Furthermore, it is preferable that the adhesive agent or adhesive member for bonding each member has dust resistance and water resistance.

FIG. 6(c) is a sectional view taken along line AA' shown in FIG. 6(a). By arranging the outer frame member 43 on the upper surface of the substrate 40 , a housing portion 431 that surrounds the first land 41 and houses the second land 42 , the dielectric member 44 and the conductive member 46 is formed.

A first electrode 402 connected to the first land 41 through a via hole 401 and a second electrode 404 connected to the second land 42 through a via hole 403 are formed on the lower surface of the substrate 40 . The pressure sensitive switch 4 is connected to an external device via the first electrode 402 and the second electrode 404 .

FIG. 7 is a cross-sectional view for explaining how the pressure-sensitive switch according to the third embodiment changes when pressed from above. (a) is a cross-sectional view when the pressure-sensitive switch is not pressed from above, and (b) is a cross-sectional view when the pressure-sensitive switch is pressed from above.

The predetermined separation distance between the dielectric member 44 and the conductive member 46 is d when the pressure sensitive switch 4 is not depressed from above. When the sealing sheet 47 is pressed from above by the pressing body 200 , the sealing sheet 47 protrudes downward and presses down the main body portion 461 of the conductive member 46 . Since the conductive member 46 is a conductive leaf spring member that is bendable and has elasticity, the main body portion 461 bends downward, and the two cutout portions 433 and 434 of the outer frame member 43 face each other. It spreads in the direction and touches each side surface of the cutouts 433 and 434 . By bending body portion 461, the distance between dielectric member 44 and conductive member 46 becomes d-Δd, which is shorter than the predetermined separation distance, and the capacitance between dielectric member 14 and conductive member 17 changes.

[Modified example of connection member]
In the pressure-sensitive switches of the first to third embodiments, the connection member is inserted into the through-hole of the outer frame member. The pressure-sensitive switch of Modification 1 is an example in which the connection member is arranged along the inner surface of the outer frame member. The pressure-sensitive switch of Modification 2 is an example in which the connection member is formed along the outer surface of the outer frame member as a conductive storage case. In order to simplify the description, a modification of the pressure-sensitive switch 1 of the first embodiment will be described, but the modification of the connecting member is not limited to the pressure-sensitive switch of the first embodiment.

8A and 8B are diagrams showing modifications of the connection member of the pressure-sensitive switch, where (a) is a cross-sectional view showing an example of the pressure-sensitive switch of modification 1, and (b) is a pressure-sensitive switch of modification 2. FIG. It is a cross-sectional view showing an example of.

The pressure-sensitive switch 5 of Modification 1 includes a substrate 10, a first land 11, a second land 52, an outer frame member 53, a dielectric member 14, a spacer frame member 15, a connecting member 56, a conductive member 57, an upper frame member 18, and a sealing sheet 19 . A connection member 56 is attached along the inner surface of the outer frame member 53 . Therefore, the second land 52 on the substrate 10 moves toward the first land 11 so as to be connected to the connecting member 56 . The via hole 503 and the second electrode 504 move to correspond to the movement of the second land 52 . A protruding portion 572 of the conductive member 57 is shortened so as to connect to the connecting member 56 . Furthermore, the outer frame member 53 is not provided with through holes and notch guides.

The pressure-sensitive switch 6 of Modification 2 includes the substrate 10, the first land 11, the second land 62, the outer frame member 63, the dielectric member 14, the spacer frame member 15, the conductive member 67, the upper frame member 18, and the sealing sheet. 19 has an electrically conductive storage case 66 . The storage case 66 is, for example, a case made of metal or conductive resin. The storage case 66 covers the sealing sheet 19 and reaches the lower surface of the substrate 10 along the outer surfaces of the outer frame member 63 and the upper frame member 18 . The second land 62 extends to the outer periphery of the substrate 10 so as to be electrically connected to the storage case 66, and the projecting portion 672 extends to the outer surface of the outer frame member 63 to be electrically connected to the storage case 66. are doing. A conductive storage case 66 functions as a connecting member.

By fixing between the storage case 66 and the sealing sheet and between the storage case 66 and the outer periphery of the substrate 10 with a waterproof adhesive, the pressure-sensitive switch 6 can be made more dustproof and waterproof. If the conductor pattern is extended from the second electrode 604 to the storage case 66 for electrical connection, the second land 62 becomes unnecessary.

[Voltage detection system for pressure sensitive switch]
An example of a voltage detection system for detecting the voltage between the first electrode and the second electrode of the pressure-sensitive switch of the present invention corresponding to depression from above will be described. To simplify the explanation, the pressure-sensitive switch 1 of the first embodiment will be described as an example, but the voltage detection system is not limited to the pressure-sensitive switch 1 of the first embodiment.

FIG. 9 shows an example of a voltage detection system for detecting the voltage between the first electrode and the second electrode of the pressure-sensitive switch of the present invention corresponding to depression from above. (b) shows a block diagram of the voltage detection system.

The pressure-sensitive switch 1 is equivalent to the variable capacitor 7 because the capacitance changes in accordance with the change in separation distance between the dielectric member 14 and the conductive member 17 when pressed from above. The first electrode 102 and the second electrode 104 correspond to terminals of the variable capacitor 7, respectively. The capacitance of the variable capacitor 7 is represented by Cs.

The voltage detection system 8 includes an oscillation circuit 81, a switched capacitor circuit 82 connected to the output terminal of the oscillation circuit 81, a sample hold circuit 83 connected to the output terminal of the switched capacitor circuit 82, and an output terminal of the oscillation circuit 81. It has a monostable multivibrator 84 connected between the sample and hold circuit 83 and an amplifier 85 connected to the output terminal of the sample and hold circuit 83 .

The switched capacitor circuit 82 includes an operational amplifier 86, a reference capacitor 87 having a capacitance of Cr connected between the inverting input terminal of the operational amplifier 86 and the oscillation circuit 81, and a capacitor between the inverting input terminal of the operational amplifier 86 and the output terminal. It has a variable capacitor 7 with a connected capacitance of Cs, and an analog switch 88 connected in parallel to the variable capacitor 7 and connected to the oscillation circuit 81 .

When the analog switch 88 is switched in synchronism with the oscillator circuit 81, a half-wave amplitude-modulated output proportional to the quotient of the capacitances of the variable capacitor 7 and the reference capacitor 87 is obtained. This output voltage Vout is
Vout=-Vp.(Cr/Cs)
is represented. Here, Vp is the applied voltage to the variable capacitor 7 and the reference capacitor 87 .

A monostable multivibrator 84 that receives the output signal of the oscillation circuit 81 generates a timing pulse and supplies it to the sample hold circuit 83 . The sample hold circuit 83 holds the output of the operational amplifier 86 at the time of receiving the timing pulse and supplies it to the amplifier 85 . The voltage detection system 8 makes it possible to detect the output voltage Vout proportional to the capacitance Cr of the variable capacitor 7 .

In the pressure-sensitive switch according to the present invention, the substrate has a rectangular planar shape, but it may have another planar shape, such as a circular shape. At least one of the first land, the outer frame member, the dielectric member, the spacer frame member, the main body portion of the conductive member, the upper frame member, and the sealing sheet, which are arranged in accordance with the shape of the substrate, has a circular planar shape. There may be.

It should be understood by those skilled in the art that various changes, substitutions and modifications can be made thereto without departing from the spirit and scope of the present invention.

1, 3, 4, 5, 6 pressure sensitive switch 10, 40 substrate 102, 402 first electrode 104, 404, 504, 604 second electrode 11, 41 first land 12, 42, 52, 62 second land 13, 43, 53, 63 Outer frame member 14, 44 Dielectric member 15 Spacer frame member 16, 45, 56, 66 Connection member 17, 46 Conductive member 18 Upper frame member 19, 47 Sealing sheet 21 Collective substrate 22 Collective adhesive sheet 23 Collective Outer frame member 24 Box 25 Collective upper frame member 26 Collective sealing sheet 27 Collective pressure sensitive switch 8 Voltage detection system

Claims (5)

a substrate;
a conductive first land disposed on the substrate;
a dielectric member disposed on the first land;
It is arranged above the dielectric member so as to be separated from the dielectric member so that the distance between the dielectric member and the dielectric member when not pressed from above is a predetermined separation distance, and when pressed from above a flexible conductive member whose distance from the dielectric member is shorter than the separation distance;
a sealing sheet disposed on the substrate and sealing the first land, the dielectric member and the conductive member;
a first electrode electrically connected to the first land;
a second electrode electrically connected to the conductive member ;
At least a portion of the conductive member is separated from the sealing sheet,
pressure sensitive switch. A spacer having a frame-like planar shape with a height equal to the separation distance , and arranged between the dielectric member and the conductive member to separate the dielectric member and the conductive member by the separation distance 2. The pressure sensitive switch of claim 1 , further comprising a frame member. 3. The pressure sensitive switch according to claim 1 , further comprising an upper frame member between said substrate and said sealing sheet. a conductive second land disposed on the substrate so as to be insulated from the first land;
an outer frame member disposed on the substrate and formed with an accommodating portion that accommodates the first land, the second land, the dielectric member, and the conductive member;
a connection member that electrically connects the second land and the conductive member;
The connection member is arranged along the inner surface of the outer frame member,
3. The conductive member has a main body portion disposed on the dielectric member, and a protruding portion extending from the main body portion in the direction of the outer frame member and electrically connected to the connecting member. The pressure sensitive switch according to any one of 1 . an outer frame member disposed on the substrate and formed with an accommodating portion for accommodating the first land, the dielectric member, and the conductive member;
a conductive storage case for storing the substrate, the first land, the outer frame member, the dielectric member, and the conductive member;
4. The conductive member has a main body portion disposed on the dielectric member, and a protruding portion extending from the main body portion to the outer surface of the outer frame member and electrically connected to the storage case. The pressure sensitive switch according to any one of 1 .

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