CN113903612A

CN113903612A - Film switch with light-emitting function, light-emitting key and light-emitting keyboard

Info

Publication number: CN113903612A
Application number: CN202111327914.5A
Authority: CN
Inventors: 朱亚兵
Original assignee: Suzhou Youyue Electronic Co ltd
Current assignee: Suzhou Youyue Electronic Co ltd
Priority date: 2021-11-10
Filing date: 2021-11-10
Publication date: 2022-01-07

Abstract

The invention discloses a membrane switch with a light-emitting function, a light-emitting key and a light-emitting keyboard, wherein the membrane switch comprises: a flexible substrate; the switch circuit layer is positioned on the front surface of the flexible substrate and comprises a plurality of conductive contacts which are not in contact with each other; the light-emitting component is integrated on the flexible substrate and used for generating light beams; the flexible key is covered on the switch circuit layer, and a pressing cavity is reserved between the inner wall of the flexible key and the flexible substrate; and the conductor is positioned in the pressing cavity and used for switching on the plurality of conductive contacts under the pressing of the flexible key so as to realize the switching on of the switch circuit layer. The membrane switch with the light-emitting function, the light-emitting key and the light-emitting keyboard have compact structures, high integration level and thin thickness, and can meet the requirements of the market on lightness and thinness of electronic products.

Description

Film switch with light-emitting function, light-emitting key and light-emitting keyboard

Technical Field

The invention relates to the technical field of membrane switches, in particular to a membrane switch with a light-emitting function, a light-emitting key and a light-emitting keyboard.

Background

Membrane switches, also known as touch keyboards, employ planar multi-layer integrated sealing structures to seal the keyswitches, the panels, the signs, the symbol displays and the lining boards together, and are widely used in various electronic products. The membrane switch mainly comprises an upper circuit board, an isolating layer and a lower circuit board, wherein when the membrane switch is pressed down, a contact of the upper circuit board deforms downwards and is in contact conduction with a contact of the lower circuit board to generate a signal. In addition, in order to satisfy the requirement of consumers for light emission by pressing, a light-emitting layer is added below the membrane switch.

That is, the existing membrane switch with light-emitting function has a four-layer structure (upper circuit board, isolation layer, lower circuit board, light-emitting layer), and the membrane switch with this structure has a thicker thickness and occupies a larger space; in addition, the existing light-emitting layer needs to be controlled by a separate IC control module, and the thickness of the IC control module occupies partial space, so that the design requirement of light and thin products is influenced to a certain extent.

Disclosure of Invention

In order to overcome the above disadvantages, the present invention provides a membrane switch, a light-emitting key and a light-emitting keyboard with a light-emitting function, which have high integration and thin thickness and can meet the market demand for thinning electronic products.

In order to achieve the above purpose, one of the technical schemes adopted by the invention is as follows: a membrane switch with a light-emitting function comprises a flexible substrate; the switch circuit layer is positioned on the front surface of the flexible substrate and comprises a plurality of conductive contacts which are not in contact with each other; the flexible key is covered on the switch circuit layer, and a pressing cavity is reserved between the inner wall of the flexible key and the flexible substrate; the conductor is positioned in the pressing cavity and used for connecting the plurality of conductive contacts under the pressing of the flexible key to realize the conduction of the switch circuit layer; the light-emitting component is integrated on the flexible substrate and used for generating light beams; the light-emitting component comprises a light-emitting circuit integrated on the back of the flexible substrate, the front of the flexible substrate is provided with a plurality of point positions communicated with the light-emitting circuit, the plurality of point positions surround the outer side of the flexible key, and the point positions are provided with LEDs with internal drive ICs.

The invention has the beneficial effects that:

1. an upper circuit board, an isolation layer and a luminescent layer in the prior art are eliminated, and a switch circuit layer and a luminescent circuit are directly integrated on a flexible substrate, namely, the original four-layer structure (the upper circuit board, the isolation layer, the lower circuit board and the luminescent layer) is integrated into a structure (the flexible substrate), so that the overall thickness of the membrane switch is effectively reduced;

2. in the switch circuit layer, the switch circuit layer is in a non-conducting state under a non-pressure state through a plurality of non-contact conductive contacts, so that the switch circuit layer can be used as a switch circuit; pressing the conductor through the flexible key enables the conductor to be in contact with the conductive contact, and then the conductive contact is triggered to conduct the switch circuit layer, and a key pressing signal is generated;

3. the light-emitting component is directly integrated on the flexible substrate integrated with the switch circuit layer, namely the light-emitting component and the switch circuit layer are integrated on one flexible substrate at the same time, so that the thickness of the membrane switch is reduced while the on-off and light-emitting functions of the membrane switch are ensured, the overall structure of the membrane switch is more compact, the thickness of the membrane switch is thinner and thinner, and the membrane switch can meet market demands;

4. the LED with the internal drive IC is internally arranged in the LED, so that the independent control of a single LED is realized, and the mounting space required by additionally arranging an IC control module is saved, so that the light-emitting component is more compact and thinner.

Further, the LED with the internal drive IC comprises an insulating main body, a conductive terminal, the internal drive IC, a light emitting chip and a light transmitting cover. The insulating main body is fixedly connected on the flexible substrate, and is provided with a conductive terminal which is communicated with the point position. The inner drive IC and the light emitting chip are fixedly connected on the conductive terminals and are electrically connected through wires. The light-transmitting cover is arranged on the internal drive IC and the LED and is fixed with the insulating main body. The insulation main body separates the internal drive IC, the light-emitting chip and the flexible substrate, and the internal drive IC, the light-emitting chip and the light-emitting circuit are electrically connected through the conductive terminals.

Further, the conductor is a metal dome sheet covered on the switch circuit layer, and the edge of the metal dome sheet is fixedly connected to the flexible substrate. The metal snap dome not only realizes the function of conductor conduction, but also realizes the function of a spring plate which rebounds when pressed; and strong mechanical knocking sound can be generated during pressing, so that the individual requirements of different users are met.

Further, the pressing cavity is internally provided with a silica gel elastic sheet covered on the switch circuit layer, the conductor is conductive silver paste coated on the inner wall of the silica gel elastic sheet facing the switch circuit layer, and the conductive silver paste is positioned right above the switch circuit layer. Compared with metal snap pieces, the silica gel elastic pieces have better pressing elasticity and good silencing effect, and can meet the individual requirements of different users; the installation space of the conductor is saved by directly arranging the conductive silver paste on the silica gel elastic sheet.

Furthermore, a silica gel elastic sheet covered on the switch circuit layer is arranged in the pressing cavity, an insulating layer surrounding the outer side of the switch circuit layer is arranged in the silica gel elastic sheet, the upper end face of the insulating layer is higher than the upper end face of the switch circuit layer, and the conductor is erected on the upper end face of the insulating layer; a pressing gap is reserved between the silica gel elastic sheet and the conductor. An isolation gap can be reserved between the conductor and the switch circuit layer through the arrangement of the insulating layer, so that the conductor is prevented from directly contacting the switch circuit layer in a non-pressing state; compared with the method that conductive silver paste is directly coated on the silica gel elastic piece, the service life of the silica gel elastic piece can be effectively prolonged through the insulating layer and the conductor which are arranged in the silica gel elastic piece.

Furthermore, a silica gel elastic sheet covering the switch circuit layer is arranged in the pressing cavity, an insulating layer surrounding the outer side of the switch circuit layer is arranged in the silica gel elastic sheet, and the upper end face of the insulating layer is higher than the upper end face of the switch circuit layer; a PET flat plate is erected on the upper end face of the insulating layer, and a pressing gap is reserved between the PET flat plate and the silica gel elastic sheet; the conductor is conductive silver paste coated on the lower end face of the PET flat plate.

Further, the insulating layer is made of a UV glue material.

Further, the thickness of the insulating layer is 2 to 4 μm or 8 to 12 μm. When the thickness of the insulating layer is 2-4 mu m, the insulating layer is only slightly higher than the upper end surface of the switch circuit layer, and when water vapor spreads, the water vapor easily crosses the insulating layer and enters the switch circuit layer, so that when the thickness of the insulating layer is 2-4 mu m, the insulating layer only can play a role in separating the conductor from the switch circuit layer; when the thickness of the insulating layer is 8-12 mu m, the insulating layer not only can separate the conductor from the switch circuit layer, but also can block water vapor outside the insulating layer, so that the water vapor is prevented from crossing the insulating layer and entering the switch circuit layer.

Further, the switch circuit board further comprises a waterproof structure, the waterproof structure is a waterproof layer surrounding the outer side of the flexible key, the lower end of the waterproof layer is fixedly connected to the flexible substrate, and the upper end face of the waterproof layer is higher than the upper end face of the switch circuit layer. Steam can be kept apart through the setting of waterproof layer, prevents the switch circuit layer oxidation that steam erosion leads to.

Further, the switch circuit layer is a copper foil circuit pattern etched on the surface of the flexible substrate, the copper foil circuit pattern comprises a pair of mutually non-contact and mutually perpendicular and outwards surrounding zigzag copper foil circuits, and each zigzag copper foil circuit is provided with at least one conductive contact.

Further, the switch circuit layer is a copper foil circuit pattern etched on the surface of the flexible substrate, the copper foil circuit pattern comprises a pair of mutually non-contact and staggered and inserted comb-tooth-shaped copper foil circuits, and each comb-tooth-shaped copper foil circuit is provided with at least one conductive contact.

In order to achieve the above purpose, the second technical scheme adopted by the invention is as follows: a luminous key comprises any one of the luminous membrane switches. The key made of the light-emitting membrane switch is more compact in structure and thinner in thickness compared with the existing key, and can meet the requirements of light weight and thinness in the market.

In order to achieve the above purpose, the invention adopts the third technical scheme that: a luminous keyboard comprises a keyboard substrate, wherein a plurality of keys are arranged on the keyboard substrate, and any one of the keys is adopted as the key. The keyboard manufactured by the keys is compact in structure, light and thin in thickness and capable of meeting the requirements of light weight and thinness in the market.

Drawings

Fig. 1 is a schematic circuit diagram of a membrane switch according to a first embodiment of the present invention;

FIG. 2 is a partial enlarged view of portion A of FIG. 1;

fig. 3 is a schematic structural diagram of a membrane switch according to a first embodiment of the invention;

fig. 4 is a schematic top view of a flexible substrate in a membrane switch according to a first embodiment of the invention;

fig. 5 is a schematic top view of a switch circuit layer in a membrane switch according to a first embodiment of the invention;

fig. 6 is a schematic structural diagram of a membrane switch according to a second embodiment of the present invention;

fig. 7 is a schematic structural diagram of a membrane switch according to a third embodiment of the present invention;

fig. 8 is a schematic structural view of another aspect of a membrane switch according to a third embodiment of the present invention;

fig. 9 is a schematic structural diagram of a membrane switch according to a fourth embodiment of the present invention;

fig. 10 is a schematic structural diagram of a membrane switch according to a fifth embodiment of the present invention;

fig. 11 is a schematic structural view of a membrane switch according to a sixth embodiment of the present invention;

fig. 12 is a schematic top view of a switch circuit layer in a membrane switch according to a seventh embodiment of the present invention.

In the figure:

11-a flexible substrate; 12-switching line layer; 121a, 121 b-zigzag copper foil circuit; 122a, 122b, 124a, 124 b-conductive contacts; 123a, 123 b-a comb-tooth copper foil circuit; 131-a light emitting circuit; 132-point location; 133-LED; 1331-an insulating body; 1332-conductive terminals; 1333-a light transmissive cover; 1334-a light emitting chip; 1335-internal drive IC; 2-flexible keys; 21-pressing the cavity; 22-key body; 23-a key contact; 3-a conductor; 4-a silica gel elastic sheet; 5-an insulating layer; 6-PET flat plate; 7-waterproof layer.

Detailed Description

The following detailed description of the preferred embodiments of the present invention, taken in conjunction with the accompanying drawings, will make the advantages and features of the invention easier to understand by those skilled in the art, and thus will clearly and clearly define the scope of the invention.

Examples

Example one

Referring to fig. 1 to 5, a membrane switch with a light emitting function includes: a flexible substrate 11, a switch circuit layer 12, a light emitting module, a flexible key 2, and a conductor 3. The switch circuit layer 12 and the light emitting component 8 are integrated on the flexible substrate 11. The flexible key 2 is covered on the switch circuit layer 12, and a pressing cavity 21 is reserved between the inner wall of the flexible key and the flexible substrate 11; the conductor 3 is located in the pressing cavity 21 for turning on the switch wiring layer 12 upon pressing of the flexible key 2.

Specifically, the switch circuit layer 12 is a copper foil circuit pattern etched on the front surface of the flexible substrate 11, as shown in fig. 5, the copper foil circuit pattern includes a pair of rectangular-square-shaped

copper foil circuits

121a and 121b which are not in contact with each other and are perpendicular to each other and surround outwards, at least one conductive contact 122a is disposed on the rectangular-square-shaped copper foil circuit 121a, and at least one conductive contact 122b is disposed on the rectangular-square-shaped copper foil circuit 121 b. The number of conductive contacts provided on the zigzag

copper foil lines

121a and 121b is kept uniform. In fig. 3, a conductive contact 122a is disposed on the meander-shaped copper foil line 121a, and a conductive contact 122b is disposed on the meander-shaped copper foil line 121 b.

In actual setting, the two rectangular-square-shaped

copper foil lines

121a and 121b can be respectively set as a positive electrode line and a negative electrode line, and when the flexible key 2 is not pressed, the positive electrode line and the negative electrode line are in a non-conductive state because the two rectangular-square-shaped

copper foil lines

121a and 121b are not in contact with each other; when the flexible key 2 is pressed, the conductor is forced to move downwards and simultaneously contacts the

conductive contacts

122a and 122b, so that the

conductive contacts

122a and 122b are connected, and further, the conduction between the positive circuit and the negative circuit is realized, when the conductor 3 connects the

conductive contacts

122a and 122b on the two rectangular

copper foil circuits

121a and 121b, the positive circuit and the negative circuit can be simultaneously conducted, and further, a key pressing signal is generated.

Copper foil circuit pattern adopts the direct whole preparation of etching process on flexible substrate, compares in traditional printed silver thick liquid circuit, can be applicable to harsh environment more, and because the etching process precision is higher, the line width and the line spacing of the copper circuit that it made compare in the printing can reduce by a wide margin (lines are more meticulous promptly), and then make two word returning line type copper foil circuit can arrange more densely on the prerequisite of not touching each other, and the clearance is littleer between two word returning line type copper foil circuit promptly. Thus, when the conductor abuts against the copper foil circuit pattern, the possibility that the conductor simultaneously contacts the two zigzag-shaped copper foil circuits is higher, the possibility that the conductive contacts on the two zigzag-shaped copper foil circuits are connected is higher, and the two zigzag-shaped copper foil circuits are easier to be connected.

In actual processing, the flexible substrate 11 may be made of polyimide or polyester film as a base material. Because the polyimide or polyester film has excellent high and low temperature resistance and tensile strength, the prepared flexible substrate can have better bending degree, and therefore, the flexible substrate can be suitable for products with bending requirements.

In this embodiment, referring to fig. 3 to 4, the flexible key 2 includes a key body 22 fixed on the flexible substrate 11, and a pressing cavity 21 is left between the key body 22 and the flexible substrate 11. The inner wall of the middle part of the key body 22 extends downwards to form a key contact 23 which is positioned right above the conductive contact of the switch circuit layer 12. When the key body 22 and the key contact 23 are pressed, the key body 22 deforms and presses down to drive the key contact 23 to move toward the switch circuit layer 12. In practice, the edge of the flexible key 2 may be glued to the flexible substrate 11 with glue (e.g. UV glue).

The conductor 3 is a metal dome arranged between the switch circuit layer 12 and the key contact 23, and the edge of the metal dome is fixedly connected to the flexible substrate 11 through waterproof glue (such as UV glue). In the process that the key contact 23 moves towards the switch circuit layer 12, the key contact 23 can be pressed against the metal dome sheet and drives the metal dome sheet to deform and move down to contact with the

conductive contacts

122a and 122b of the switch circuit layer 12, so that the switch circuit layer 12 is conducted, and a key pressing signal is generated.

In this embodiment, adopt metal snap dome as the conductor, both realized electrically conductive function, had the shell fragment function of pressing the resilience again concurrently, be equivalent to unite two into one conductor, shell fragment, saved spare part. Moreover, when the metal snap is pressed, the metal snap can generate strong mechanical knocking sound, and the requirement of partial users on strong knocking feeling is met. In addition, glue through the UV with the edge of metal dome piece admittedly to flexible substrate, firstly realize the fixed of metal dome piece, secondly make the inside of metal dome piece form an airtight space, effectively isolated steam avoids steam to corrode on the circuit layer, causes the oxidation on switch circuit layer.

In this embodiment, the light emitting device includes a light emitting circuit 131 integrated on the back surface of the flexible substrate 11, the front surface of the flexible substrate 11 is provided with a plurality of points 132 electrically connected to the light emitting circuit 131, the points 132 are located on the same side as the switch circuit layer 12 and are disposed on the outer side of the flexible key 2 for soldering an LED 133 with an internal driver ic (integrated circuit). The independent control of the single internal drive IC on the corresponding LED is realized by arranging the internal drive IC in the LED 133, so that the light emission of the single key is controlled conveniently.

The LED structure with the internal drive IC is as follows:

referring to fig. 3, the LED 133 with an internal driver IC includes an insulating body 1331, a conductive terminal 1332, an internal driver IC1335, a light emitting chip 1334, and a light transmissive cover 1333. The insulating main body 1331 is fixedly connected to the flexible substrate 11 located at the outer side of the flexible key 2, and a conductive terminal 1332 is disposed on the insulating main body and is conducted with the point 132. The internal drive IC1335 and the light emitting chip 1334 are fixed on the conductive terminal 1332 by welding, and the internal drive IC1335 and the light emitting chip 1334 are electrically connected through a wire. The light-transmitting cover 1333 covers the insulating main body 1331, and two ends of the light-transmitting cover are clamped and fixed with the insulating main body 1332 or fixed with threads. The internal drive IC1335 and the light emitting chip 1334 are both located in the light transmissive cover 1333.

The conductive terminal 1332 includes a plurality of conductive pins embedded in the insulating main body 1331, and the lower ends of the conductive pins extend out of the insulating main body 1331 and electrically contact the point locations 132. The upper ends of the plurality of conductive fillets extend out of the insulating body 1331 and are commonly connected to a conductive pad. The internal drive IC1335 and the light emitting chip 1334 are both fixed to the conductive pad.

The internal drive IC1335 is arranged in the light-transmitting cover 1333, and the internal drive IC1335 is directly electrically connected with the light-emitting chip 1334 through a lead, so that the aim of integrating the internal drive IC1335 and the light-emitting chip 1334 is fulfilled, the independent control light emission of a single LED by the single internal drive IC1335 is realized, the space occupied by an additional IC control module is reduced through the internal drive IC, the thin production of a product is facilitated, and the internal drive IC 35 and the light-emitting chip 1334 are directly connected in the light-transmitting cover 1333 through leads, so that the light emission of the light-emitting chip 1334 is more stable and reliable.

In this embodiment, the light-transmitting cover 1333 may be made of epoxy resin. The epoxy resin has high light transmittance, high refractive index, good heat resistance, moisture resistance, insulativity, high mechanical strength and chemical stability, and can realize good light transmittance function and good insulation protection performance.

In this embodiment, the front surface and the back surface of the flexible substrate 11 are further coated with an insulating black glue coating, and the insulating black glue coating on the front surface is provided with through holes corresponding to the conductive contacts and the point locations. The oxidation speed of the copper foil circuit pattern can be slowed down by coating the insulating black glue coating.

Compared with the prior art, the upper circuit board, the isolation layer and the light-emitting layer in the prior art are omitted, the switch circuit layer with the switch circuit function and the light-emitting circuit with the light-emitting function are directly integrated on the flexible substrate, namely the original four-layer structure (the upper circuit board, the isolation layer, the lower circuit board and the light-emitting layer) is integrated into one structure (the flexible substrate), and the overall thickness of the membrane switch is effectively reduced; and then the metal dome sheet can contact the conductive contact on the switch circuit layer by pressing the metal dome sheet through the flexible key, so that two circle-shaped copper foil circuits on the circuit layer are conducted, and the generation of a key pressing signal is realized.

Example two

In the first embodiment, the membrane switch using the metal dome as the conductor generates a strong metal knocking feeling when being pressed, but in actual use, some users have a requirement of pressing silence. In order to meet the personalized requirements of users, the present embodiment improves the conductor of the membrane switch of the first embodiment, and the difference between the conductor and the first embodiment is that: replacing the metal dome sheet with a silica gel elastic sheet, and coating conductive silver paste on the silica gel elastic sheet to serve as a conductor.

Specifically, referring to fig. 6, a silicone elastic sheet 4 covering the switch circuit layer 12 is disposed in the pressing cavity 21, and an edge of the silicone elastic sheet 4 is fixedly connected to the flexible substrate 11 through a waterproof adhesive (e.g., UV adhesive). The conductor 3 is conductive silver paste coated on the inner wall of the silica gel elastic sheet 4, and the conductive silver paste is positioned right above the switch circuit layer 12. When the flexible key 2 is pressed down, the flexible key 2 can be pressed against the silica gel elastic sheet 4, and the silica gel elastic sheet 4 is driven to deform and move down to contact the switch circuit layer 12, so that the switch circuit layer 12 is conducted.

Compared with a metal snap sheet, the silicone elastic sheet has better pressing elasticity and better hand feeling experience, and the sound generated during pressing is extremely small, so that the requirement of a user on mute pressing can be met; through directly setting up conductor (electrically conductive silver thick liquid) on the silica gel shell fragment, both saved the installation space of conductor, still make the power of applying on the silica gel shell fragment directly transmit electrically conductive silver thick liquid on, reduce the loss of pressing force.

EXAMPLE III

When the membrane switch is tested, the applicant finds that in the second embodiment, the wear resistance of the silica gel elastic piece 4 may be reduced by directly coating the conductive silver paste on the inner wall of the silica gel elastic piece 4, which directly shortens the service life of the silica gel elastic piece 4; therefore, the present embodiment improves the installation position and manner of the conductor of the second embodiment, and the difference from the second embodiment is that: and separating the conductor 3 from the silica gel elastic sheet 4.

Specifically, referring to fig. 7, a silicone elastic sheet 4 covering the switch circuit layer 12 is disposed in the pressing cavity 21, and an edge of the silicone elastic sheet 4 is fixedly connected to the flexible substrate 11 through a waterproof adhesive (e.g., UV adhesive) to form a cavity. An insulating layer 5 surrounding the outside of the switch circuit layer 12 is arranged in the cavity of the silica gel elastic sheet 4, the lower end of the insulating layer 5 is fixedly connected to the flexible substrate 11, and the upper end face of the insulating layer 5 is higher than the upper end face of the switch circuit layer 12. The insulating layer 5 may be in a closed loop, square or other closed configuration. Illustratively, the height of the insulating layer 5 is set to 3 μm. In the actual design, the height of the insulating layer 5 may be set to 2-4 μm according to actual requirements. The conductor 3 is fixed on the upper end face of the insulating layer 5, and a pressing gap is reserved between the conductor 3 and the silica gel elastic sheet 4. The insulating layer 5 is made of UV glue or other insulating materials. The conductor 3 is made of a flat conductive material.

The silica gel elastic sheet 4 is separated from the conductor 3 through the arrangement of the pressing gap, so that the problem that the abrasion resistance of the silica gel elastic sheet 4 is reduced due to the fact that the conductor 3 is directly integrated on the silica gel elastic sheet 4 is solved; the insulating layer 5 is arranged to leave an isolation gap between the conductor 3 and the switch circuit layer 12, so that the conductor 3 is prevented from directly contacting the switch circuit layer 12 in a non-pressed state. And adopt UV glue as insulating layer 5 both realized the sticky fixed to the conductor, can play certain waterproof effect again. When the flexible key 2 is pressed down, the flexible key 2 can be abutted against the silica gel elastic sheet 4, the silica gel elastic sheet 4 is driven to deform and press down the conductor 3, and the conductor 3 moves down along with the silica gel elastic sheet and contacts the switch circuit layer 12 positioned in the insulating layer 5, so that the switch circuit layer 12 is conducted.

Compared with the second embodiment, the membrane switch of the embodiment can effectively prolong the service life of the silica gel elastic sheet while ensuring mute pressing, and meets the requirement of a user on the number of times of knocking the membrane switch.

As another alternative of this embodiment, referring to fig. 8, the conductor 3 is not directly laid on the upper end face of the insulating layer 5, but a PET plate 6 is laid on the upper end face of the insulating layer 5, and a conductive silver paste is coated on the lower end face of the PET plate 6 as the conductor 3. Wherein, the PET flat plate is a polyester plate.

Example four

Because the switch circuit layer of this application is integrated on a flexible substrate with just, negative pole circuit, appears the circuit oxidation phenomenon because of steam when the switch circuit layer, and just, the negative pole circuit on the switch circuit layer on the same flexible substrate very easily appears the phenomenon of simultaneously oxidation damage, leads to a plurality of conductive joint all can't be put through, and consequently, this embodiment further improves membrane switch's waterproof performance.

The difference between this embodiment and the third embodiment is that: the height of the insulating layer 5 is 8-12 μm.

Specifically, referring to fig. 9, the height of the insulating layer 5 is directly raised to 10 μm in this embodiment, so that the insulating layer 5 forms a barrier surrounding the switch wiring layer 12, which directly functions to enhance the waterproof performance. When water vapor spreads on the flexible substrate, the insulating layer 5 can play a good role in blocking due to the higher height setting. When water vapor moves towards the switch circuit layer 12, the insulating layer surrounding the outer side of the switch circuit layer 12 forms an annular barrier similar to the dam principle, so that the water vapor is isolated at the outer side of the insulating layer 5, and the corrosion of the water vapor to the switch circuit layer is further avoided. It should be noted that, in order to enhance the waterproof performance, the height of the insulating layer is not limited to 10 μm, and the designer may set it to 8-12 μm according to the actual design requirement.

EXAMPLE five

In the testing of the membrane switch, the applicant finds that the membrane switch of the fourth embodiment can obviously feel that the pressing hand feeling is hard when the membrane switch is pressed because the height of the insulating layer is greatly different from that of the switch circuit layer, so that the embodiment cancels the insulating layer with the waterproof function in the fourth embodiment on the basis of the fourth embodiment, sets the height of the insulating layer to be 2-4 μm, and sets the waterproof structure on the outer side of the flexible key.

The height of the insulating layer is set to be 2-4 mu m and is only slightly higher than the switch circuit layer, so that the waterproof effect of the switch circuit layer is limited, and water vapor easily passes through the insulating layer and enters the insulating layer to corrode the switch circuit layer in the insulating layer. Therefore, referring to fig. 10, the waterproof structure of the present embodiment is a waterproof layer 7 surrounding the flexible key 2, and the waterproof layer 7 is fixed to the flexible substrate 11 at its lower end and is higher than the upper end of the switch circuit layer 12 at its upper end. The height of the waterproof layer 7 is 8-12 μm. The waterproof layer 7 is a closed ring structure to completely surround the flexible key 2. The waterproof layer 7 is a UV glue layer. Establish the waterproof layer through adding in the outside of flexible button, just keep apart steam from the outside of flexible button, and then avoid steam to enter into the inside of flexible button, realized the holistic waterproof protection of flexible button, set up the waterproof layer in the outside of flexible button moreover for highly can not influence the feeling that the flexible button pressed of waterproof layer.

When steam stretchs on flexible substrate 11, because the stopping of waterproof layer 7, steam is directly isolated in the outside of waterproof layer 7, and then has blockked in steam enters into flexible button 2, has realized the water proof to switch circuit layer 12 in the flexible button 2.

EXAMPLE six

The difference between this embodiment and any one of the first to third embodiments is: a waterproof structure is added, as shown in fig. 11, the waterproof structure is a waterproof layer 7 surrounding the outer side of the flexible key 2, the lower end of the waterproof layer 7 is fixedly connected to the flexible substrate 11, and the upper end surface of the waterproof layer 7 is higher than the upper end surface of the circuit layer 12. The height of the waterproof layer 7 is not less than 8 μm. The waterproof layer 7 is a UV glue layer. The waterproof layer 7 is a closed annular structure to completely surround the flexible key.

EXAMPLE seven

The difference between this embodiment and any one of the first to sixth embodiments is: the copper foil circuit patterns are different.

Specifically, referring to fig. 12, the copper foil circuit pattern in the present embodiment includes a pair of interlaced comb-shaped

copper foil circuits

123a, 123b that are not in contact with each other, at least one conductive contact 124a is disposed on the comb-shaped copper foil circuit 123a, and at least one conductive contact 124b is disposed on the comb-shaped copper foil circuit 123 b. Illustratively, in fig. 10, five conductive contacts 124a are provided on the comb-shaped copper foil line 123a, and five conductive contacts 124b are provided on the comb-shaped copper foil line 123 b.

In actual installation, the two comb-tooth-shaped

copper foil lines

123a and 123b can be respectively set as a positive electrode line and a negative electrode line, and when the flexible key 2 is not pressed, the positive electrode line and the negative electrode line are in a non-conduction state because the two comb-tooth-shaped

copper foil lines

123a and 123b are not in contact with each other; when the flexible key 2 is pressed, the conductor is forced to move downwards and simultaneously contacts the

conductive contacts

124a and 124b, so that the

conductive contacts

124a and 124b are connected, and further, the conduction between the positive circuit and the negative circuit is realized, when the conductor 3 connects the

conductive contacts

124a and 124b on the two comb-tooth-shaped

copper foil circuits

123a and 123b, the positive circuit and the negative circuit can be simultaneously conducted, and further, a key pressing signal is generated.

In the present embodiment, the closer the comb teeth of the two comb-tooth-shaped copper foil lines are arranged, the more likely the conductor 3 is to simultaneously contact the conductive contacts on the two comb-tooth-shaped copper foil lines, and the more easily the two lines are conducted.

Example eight

A key with a membrane switch of this embodiment includes the membrane switch of any one of embodiments one to seven. This button compares in current button, and the structure is compacter, and thickness is more frivolous, can adapt to market lightweight, extremely thin demand.

Example nine

The keyboard with the membrane switch comprises a keyboard substrate, wherein a plurality of keys are arranged on the keyboard substrate, and the keys in the eighth embodiment are adopted. The keyboard has the characteristics of compact structure, light thickness and thinness, and can meet the requirements of light weight and thinness in the market.

The above embodiments are merely illustrative of the technical concept and features of the present invention, and the present invention is not limited thereto, and equivalent changes and modifications made according to the spirit of the present invention should be covered thereby.

Claims

1. A membrane switch with a light-emitting function is characterized by comprising:

a flexible substrate;

the switch circuit layer is positioned on the front surface of the flexible substrate and comprises a plurality of conductive contacts which are not in contact with each other;

the flexible key is covered on the switch circuit layer, and a pressing cavity is reserved between the inner wall of the flexible key and the flexible substrate;

the conductor is positioned in the pressing cavity and used for switching on the plurality of conductive contacts under the pressing of the flexible key so as to realize the conduction of the switch circuit layer;

the light-emitting component is integrated on the flexible substrate and used for generating light beams; the light-emitting assembly comprises a light-emitting circuit integrated on the back surface of the flexible substrate, the front surface of the flexible substrate is provided with a plurality of point positions communicated with the light-emitting circuit, and the plurality of point positions surround the outer side of the flexible key; and the point positions are provided with LEDs with internal drive ICs.

2. The membrane switch of claim 1, wherein the LED with the internal driver IC comprises an insulating body, a conductive terminal, an internal driver IC, a light emitting chip, and a light transmissive cover; the insulating main body is fixedly connected to the flexible substrate, and a conductive terminal which is communicated with the point position is arranged on the insulating main body; the internal drive IC and the light-emitting chip are fixedly connected on the conductive terminal and are electrically connected through a lead; the light-transmitting cover is arranged on the internal drive IC and the LED and is fixed with the insulation main body.

3. The membrane switch of claim 2, wherein the conductor is a metal dome covering the switch circuit layer, and an edge of the metal dome is fixed to the flexible substrate.

4. The membrane switch of claim 2, wherein a silicone spring piece covered on the switch circuit layer is arranged in the pressing cavity, the conductor is conductive silver paste coated on an inner wall of the silicone spring piece facing the switch circuit layer, and the conductive silver paste is located right above the switch circuit layer.

5. The membrane switch of claim 2, wherein a silicone spring covering the switch circuit layer is arranged in the pressing cavity, an insulating layer surrounding the switch circuit layer is arranged in the silicone spring, the upper end face of the insulating layer is higher than the upper end face of the switch circuit layer, and the conductor is erected on the upper end face of the insulating layer.

6. The membrane switch of claim 5, wherein a pressing gap is left between the silicone dome and the conductor.

7. The membrane switch of claim 2, wherein a silicone spring covering the switch circuit layer is arranged in the pressing cavity, an insulating layer surrounding the switch circuit layer is arranged in the silicone spring, and the upper end surface of the insulating layer is higher than the upper end surface of the switch circuit layer; a PET flat plate is erected on the upper end face of the insulating layer, and a pressing gap is reserved between the PET flat plate and the silica gel elastic sheet; the conductor is conductive silver paste coated on the lower end face, facing the switch circuit layer, of the PET flat plate.

8. The membrane switch according to any of claims 5 to 7, characterized in that the insulating layer is made of a UV glue material.

9. The membrane switch of claim 7, wherein the height of the insulating layer is 2-4 μm or 8-12 μm.

10. The membrane switch according to any one of claims 1 to 7, further comprising a waterproof structure, wherein the waterproof structure is a waterproof layer surrounding the outer side of the flexible key, the waterproof layer is fixedly connected to the flexible substrate at a lower end thereof, and an upper end surface thereof is higher than an upper end surface of the switch circuit layer.

11. The membrane switch according to any of claims 1 to 10, wherein the switch circuit layer is a copper foil circuit pattern etched on the surface of the flexible substrate, the copper foil circuit pattern comprises a pair of zigzag copper foil circuits which are not in contact with each other, and each of the zigzag copper foil circuits is provided with at least one conductive contact.

12. The membrane switch according to any of claims 1 to 10, wherein the switch circuit layer is a copper foil circuit pattern etched on the surface of the flexible substrate, the copper foil circuit pattern comprises a pair of comb-shaped copper foil circuits which are not in contact with each other and are interleaved, and each of the comb-shaped copper foil circuits is provided with at least one conductive contact.

13. An illuminated key comprising a membrane switch according to any one of claims 1 to 12.

14. A light-emitting keyboard, comprising a keyboard substrate, wherein a plurality of keys are disposed on the keyboard substrate, and the keys are the keys according to claim 13.