TW202305852A - Membrane circuit board and keyboard device using the same - Google Patents

Abstract

The present invention discloses a membrane circuit board used in a key structure of a keyboard device, the key structure including an elastic element. The membrane circuit board includes a first membrane substrate and a membrane conduction module. The first membrane substrate includes a first conductive contact and a second conductive contact disposed on a top surface. The elastic element is vertically projected toward the first membrane substrate to form a projection area on the top surface, and the first conductive contact and the second conductive contact are located in the projection area. The membrane conduction module is disposed between the elastic element and the first membrane substrate and is located in the projection area. The membrane conduction module includes a third conductive contact. The first conductive contact and the second conductive contact are opposed to the third conductive contact respectively.

Description

Thin film circuit board and keyboard device with thin film circuit board

The invention relates to the field of input devices, in particular to a thin film circuit board applied to a keyboard device.

With the rapid development of science and technology, the vigorous development of electronic equipment has brought a lot of convenience to human life, so how to make the operation of electronic equipment more humanized is an important issue. Common input devices of electronic equipment include a mouse device, a keyboard device, and a trackball device, among which the keyboard device can be used for users to directly input characters and symbols into the computer, so it is highly valued.

The keyboard device includes multiple key structures, and each key structure mainly includes sequentially stacked key caps, scissor-type connection components, thin film circuit boards, and key bottom plates. Backlight module. Specifically, a membrane switch is provided on the membrane circuit board, and an elastic element is arranged between the key cap and the membrane circuit board. The first frame is the second frame, so the first frame and the second frame can swing relative to each other. Wherein, when the keycap of any key structure is pressed and moves downward relative to the key bottom plate, the first frame and the second frame of the scissor-type connection assembly will change from the open-close state to the folded state, and move downward The keycap will squeeze the elastic element, so that the elastic element will touch and trigger the corresponding membrane switch, so that the keyboard device will generate a corresponding key signal. And when the key cap of the key structure is no longer pressed, the key cap will move upward relative to the key bottom plate in response to the elastic restoring force of the elastic element, and at this time the first frame and the second frame will change from the overlapping state to the open state. and the keycap will return to its original position.

A conventional thin film circuit board of a keyboard device includes an upper thin film substrate, a lower thin film substrate, and a middle thin film substrate between the upper thin film substrate and the lower thin film substrate. The lower surface of the upper film substrate has a first circuit pattern, and the first circuit pattern has a plurality of upper contacts and a plurality of upper silver glue lines respectively corresponding to the above-mentioned button structures. The upper surface of the lower film substrate has a second circuit pattern, and the second circuit pattern has a plurality of lower contacts and a plurality of lower silver glue lines respectively corresponding to the upper contacts. In addition, the middle film substrate has a plurality of openings respectively corresponding to the upper contacts and the lower contacts. Each above-mentioned upper contact and its corresponding lower contact jointly form the above-mentioned membrane switch.

However, conventional thin film circuit boards are formed by stacking an upper film substrate, a lower film substrate, and an intermediate film substrate with approximately the same size (such as the same surface area). Under such a structural design, the keyboard device cannot be thinned. the goal of. Therefore, how to improve the above problems is actually the focus of attention of relevant people in the field.

One of the objectives of the present invention is to provide a thin film circuit board.

Another object of the present invention is to provide a keyboard device having a thin film circuit board.

Other purposes and advantages of the present invention can be further understood from the technical features disclosed in the present invention.

In order to achieve one or part or all of the above objectives or other objectives, the present invention provides a thin film circuit board, which is used in a key structure of a keyboard device, and the key structure includes elastic elements. The thin film circuit board includes a first thin film substrate and a thin film conduction module. The first film substrate includes a first conductive contact and a second conductive contact arranged on the top surface, and the elastic element projects vertically toward the first film substrate to form a projected area on the top surface, and the first conductive contact and the second conductive contact The conductive contacts are located within the projected area. The film conduction module is arranged between the elastic element and the first film substrate and is located in the projection area. The film conduction module includes a third conductive contact, and the first conductive contact and the second conductive contact respectively correspond to the third conductive contact.

In an embodiment of the present invention, the above-mentioned thin film conduction module includes a second thin film substrate and a spacer substrate stacked on each other, the second film substrate is located between the elastic element and the spacer substrate, and the second film substrate has a The bottom surface of the substrate, the third conductive contact is arranged on the bottom surface, the spacer substrate is located between the first film substrate and the second film substrate, and the spacer substrate makes the first conductive contact and the second conductive contact respectively connected with the third film substrate There is a separation distance between the conductive contacts.

In an embodiment of the present invention, the above-mentioned spacer substrate includes through holes. The through hole is located between the first conductive contact, the second conductive contact of the first film substrate and the third conductive contact of the thin film conduction module. In this conduction state, the third conductive contact passes through the through hole and contacts at the first conductive contact and the second conductive contact.

In an embodiment of the present invention, the above-mentioned first film substrate, second film substrate and spacer substrate are made of polyethylene terephthalate.

In an embodiment of the present invention, the above-mentioned elastic element includes a surrounding wall and an annular bottom, the surrounding wall extends toward the direction close to the first film substrate and is connected to the annular bottom, and the annular bottom projects vertically toward the first film substrate to form a projected area , and the annular bottom has an outer diameter length and an inner diameter length.

In an embodiment of the present invention, the above-mentioned second film substrate has a first outer diameter length, the spacer substrate has a second outer diameter length, the outer diameter length of the annular bottom, the first outer diameter length of the first film substrate, and the spacer The lengths of the second outer diameters of the substrates are equal to each other.

In an embodiment of the present invention, the above-mentioned second film substrate has a first outer diameter length, the spacer substrate has a second outer diameter length, and the first outer diameter length of the first film substrate is equal to the second outer diameter length of the spacer substrate. , and the length of the first outer diameter of the first film substrate and the length of the second outer diameter of the spacer substrate are respectively smaller than the length of the inner diameter of the annular bottom.

In an embodiment of the present invention, the area of the projected area formed by the elastic element on the first film substrate is smaller than the surface area of the top surface of the first film substrate.

In an embodiment of the present invention, the above-mentioned first film substrate further includes a first metal circuit and a second metal circuit, the first metal circuit is disposed on the top surface and extends from the first conductive contact to the outside of the projected area. On one side, the second metal circuit is disposed on the top surface and extends from the second conductive contact to the other side outside the projection area.

In an embodiment of the present invention, at least one of the above-mentioned first metal circuit and the second metal circuit is a silver paste circuit.

The present invention further provides a keyboard device, which includes a plurality of key structures, and each key structure includes a key cap, an elastic element and a film circuit board. The elastic element is arranged under the key cap. The film circuit board is arranged under the elastic element. The thin film circuit board includes a first thin film substrate and a thin film conduction module. The first film substrate includes a first conductive contact and a second conductive contact arranged on the top surface, and the elastic element projects vertically toward the first film substrate to form a projected area on the top surface, and the first conductive contact and the second conductive contact The conductive contacts are located within the projected area. The film conduction module is arranged between the elastic element and the first film substrate and is located in the projection area. The film conduction module includes a third conductive contact, and the first conductive contact and the second conductive contact respectively correspond to the third conductive contact.

In the thin film circuit board of the embodiment of the present invention, the size of the first thin film substrate used is different from the size of the thin film conduction module formed by the second thin film substrate and the spacer substrate. In the embodiment of the present invention, both the second film substrate and the spacer substrate are located within the vertical projection range of the vertical projection of the elastic element on the first film substrate, that is, the outer diameter of the second film substrate and the outer diameter of the spacer substrate are respectively equal to The outer diameter of the annular bottom of the elastic element, or the outer diameter of the second film substrate and the outer diameter of the spacer substrate are respectively smaller than the inner diameter of the annular bottom of the elastic element. Under such a structural design, the overall thickness of the thin film circuit board is actually Only the thickness of the first thin film substrate remains, so that the overall thickness of the thin film circuit board is effectively reduced to achieve the purpose of thinning.

In order to make the above and other objects, features and advantages of the present invention more comprehensible, preferred embodiments will be described in detail below together with the attached drawings.

Please refer to FIG. 1 to FIG. 4 . FIG. 1 is a schematic diagram of the appearance and structure of a keyboard device according to an embodiment of the present invention. FIG. 2 is a schematic perspective view of the key structure shown in FIG. 1 . FIG. 3 is a schematic cross-sectional view along line AA shown in FIG. 2 . FIG. 4 is an exploded schematic view of the key structure shown in FIG. 2 . For a clearer illustration, FIG. 2 to FIG. 4 only show a single button structure and its related components.

As shown in FIGS. 1 to 4 , the keyboard device 1 of this embodiment includes a plurality of key structures 10 . Each key structure 10 includes a key cap 101 , an elastic element 102 and a film circuit board 103 . The keycap 101 is disposed above the elastic element 102 . The elastic element 102 is disposed between the keycap 101 and the thin film circuit board 103 . In this embodiment, these button structures 10 can be classified into general keys, number keys, function keys, etc., which are respectively pressed by the user's fingers to make the keyboard device 1 generate a corresponding word key input signal to the computer, thereby enabling The computer performs corresponding functions, for example, the general keys are used to input symbols such as English letters, the number keys are used to input numbers, and the function keys are used to provide various shortcut functions, such as F1~F12, etc. Multiple keys such as longer blank key (Space) or displacement (Shift) key. It should be noted that, in order to clearly express the connection relationship between the elastic element 102 and the film circuit board 103 , the keycap 101 shown in FIG. 1 is omitted from FIGS. 2 to 4 .

It should be noted that the thin film circuit board 103 of this embodiment is disposed under the plurality of key structures 10 (as shown in FIG. 1 ) in the keyboard device 1 . Generally speaking, besides the above-mentioned key cap 101, elastic element 102 and film circuit board 103, the key structure 10 further includes components such as scissor-type connection components and a key base plate, but these components are not the focus of the present invention, and these The connection relationship between the components and other components is known in the art, so it will not be repeated here.

As shown in FIGS. 2 to 4 , the thin film circuit board 103 of this embodiment includes a first thin film substrate 1031 and a thin film conduction module 1032 . The first film substrate 1031 includes a first conductive contact C1 and a second conductive contact C2 disposed on the top surface F1 . In this embodiment, the elastic element 102 above the thin film circuit board 103 projects vertically toward the first film substrate 1031 to form a projected area R on the top surface F1, the first conductive contact C1 of the first film substrate 1031 and the second The conductive contacts C2 are all located within the range of the projection area R mentioned above. The thin film conduction module 1032 is disposed between the elastic element 102 and the first film substrate 1031 , and the thin film conduction module 1032 is located within the range of the projection area R mentioned above. The thin film conduction module 1032 includes a third conductive contact C3, the first conductive contact C1 and the second conductive contact C2 of the first film substrate 1031 respectively correspond to the third conductive contact C3 of the thin film conduction module 1032, Moreover, a membrane switch is formed between the first conductive contact C1 , the second conductive contact C2 and the third conductive contact C3 .

As shown in FIGS. 2 to 4 , the thin film conduction module 1032 of this embodiment includes a second thin film substrate 10321 and a spacer substrate 10322 . The second film substrate 10321 and the spacer substrate 10322 are stacked on each other, the second film substrate 10321 is located between the elastic element 102 and the spacer substrate 10322, and the second film substrate 10321 has a bottom surface F2 facing the first film substrate 1031, and the film conducts The third conductive contact C3 of the module 1032 is disposed on the bottom surface F2 of the second film substrate 10321 . The spacer substrate 10322 is located between the first film substrate 1031 and the second film substrate 10321, and the spacer substrate 10322 makes the first conductive contact C1, the second conductive contact C2 on the first film substrate 1031 and the second film substrate on the second film substrate There is a distance between the third conductive contacts C3 on 10321.

It should be noted that the projected area R formed by the elastic element 102 on the top surface F1 of the first film substrate 1031 includes the space area directly above the projected area R, therefore, the second film substrate 10321 of the film conduction module 1032 Both the second film substrate 10321 and the spacer substrate 10322 are located within the range of the projected region R, that is, the maximum surface area of the second film substrate 10321 and the spaced substrate 10322 is smaller than or equal to the area of the projected region R. In addition, in this embodiment, the projected region R formed by the elastic element 102 on the top surface F1 of the first film substrate 1031 has an area smaller than the surface area of the top surface F1 of the first film substrate 1031 . Under such a structural design, when the film conduction module 1032 and the elastic element 102 are assembled with each other, the film conduction module 1032 and the elastic element 102 will present an integrally formed appearance, so when the film conduction module 1032 is assembled with each other After being disposed on the first thin film substrate 1031 with the elastic element 102 , the overall thickness of the thin film circuit board 103 is actually only the thickness of the first thin film substrate 1031 , which effectively reduces the overall thickness of the thin film circuit board 103 and achieves the purpose of thinning.

As shown in FIGS. 2 to 4 , the spacer substrate 10322 of this embodiment includes a through hole H. As shown in FIG. The through hole H is located between the first conductive contact C1 and the second conductive contact C2 of the first film substrate 1031 and the third conductive contact C3 of the film conductive module 1032 . In the conduction state, the third conductive contact C3 passes through the through hole H of the spacer substrate 10322 and contacts the first conductive contact C1 and the second conductive contact C2 .

As shown in FIG. 2 and FIG. 4 , the first film substrate 1031 of this embodiment further includes a first metal line L1 and a second metal line L2 . The first metal line L1 is disposed on the top surface F1 and constitutes a first circuit pattern P1 with the first conductive contact C1 . The first metal line L1 extends from the first conductive contact C1 to a side outside the projected area R. The second metal line L2 is disposed on the top surface F1 and forms a second circuit pattern P2 with the second conductive contact C2, that is, the second metal line L2 extends from the second conductive contact C2 to another part of the projection area R. side. Since there is a gap G between the first conductive contact C1 and the second conductive contact C2 , in the non-conductive state, the first circuit pattern P1 and the second circuit pattern P2 are in an open circuit state. In this embodiment, the first metal circuit L1 and the second metal circuit L2 are, for example, silver paste circuits, but the present invention is not limited thereto.

It should be noted that the materials of the first film substrate 1031, the second film substrate 10321 and the spacer substrate 10322 in this embodiment are, for example, polyethylene terephthalate (PET for short), but the present invention does not This is the limit. The first circuit pattern P1 and the second circuit pattern P2 in this embodiment are formed on the top surface F1 of the first film substrate 1031 according to a specified shape by printing, for example, but the invention is not limited thereto. The thin film circuit board 103 of the present embodiment can be configured as an external keyboard (for example, a keyboard with a PS2 interface, a keyboard with a USB interface, or a mechanical keyboard) used by a desktop computer, a notebook computer or a laptop computer. Built-in keyboard, but the present invention is not limited thereto, that is to say, the concept of the thin circuit board 2 of the embodiment of the present invention can be applied to any electronic product that uses the thin film circuit board 103 as a signal input interface.

As shown in FIGS. 2 to 4 , the elastic element 102 of this embodiment includes a surrounding wall 1021 and an annular bottom 1022 . The surrounding wall 1021 extends toward the direction close to the first film substrate 1031 and is connected to the annular bottom 1022 . The annular bottom 1022 of the elastic element 102 is vertically projected toward the first film substrate 1031 to form the above-mentioned projection area R on the top surface F1. Specifically, the projection area R is that the opening of the annular bottom 1022 of the elastic element 102 faces the first film substrate The direction 1031 is then vertically projected on the top surface F1 of the first film substrate 1031 . Furthermore, the annular bottom 1022 of the elastic element 102 has an outer diameter length D. As shown in FIG. In this embodiment, the second film substrate 10321 of the film conduction module 1032 has a first outer diameter D1, the spacer substrate 10322 has a second outer diameter D2, the first outer diameter D1 of the second film substrate 10321, the spacer substrate 10322 The second outer diameter D2 and the outer diameter D of the annular bottom 1022 of the elastic element 102 are equal to each other.

Please refer to FIG. 5 , which is a schematic cross-sectional view of a button structure according to another embodiment of the present invention. As shown in FIG. 5 , the button structure 10a of this embodiment is similar to the button structure 10 shown in FIGS. The thin film conduction module 1032 shown in FIG. 4 has different dimensions. In this embodiment, the annular bottom 1022 of the elastic element 102 has an inner diameter length D', and the first outer diameter D1' of the second film substrate 10321 of the film conduction module 1032a is equal to the second outer diameter D2' of the spacer substrate 10322 , and the first outer diameter D1' of the second film substrate 10321 and the second outer diameter D2' of the spacer substrate 10322 are respectively smaller than the inner diameter length D' of the annular bottom 1022 of the elastic element 102. Under such a structural design, the film conduction The module 1032a is located in the containing space defined by the surrounding wall 1021 and the annular bottom 1022 .

To sum up, in the thin film circuit board of the embodiment of the present invention, the size of the first thin film substrate used is different from the size of the thin film conduction module composed of the second thin film substrate and the spacer substrate. In the embodiment of the present invention, both the second film substrate and the spacer substrate are located within the vertical projection range of the vertical projection of the elastic element on the first film substrate, that is, the outer diameter of the second film substrate and the outer diameter of the spacer substrate are respectively equal to The outer diameter of the annular bottom of the elastic element, or the outer diameter of the second film substrate and the outer diameter of the spacer substrate are respectively smaller than the inner diameter of the annular bottom of the elastic element. Under such a structural design, the overall thickness of the thin film circuit board is actually Only the thickness of the first thin film substrate remains, so that the overall thickness of the thin film circuit board is effectively reduced to achieve the purpose of thinning.

But what is described above is only a preferred embodiment of the present invention, and should not limit the scope of implementation of the present invention with this, that is, all simple equivalent changes and modifications made according to the patent scope of the present invention and the content of the description of the invention, All still belong to the scope covered by the patent of the present invention. In addition, any embodiment or scope of claims of the present invention does not necessarily achieve all the objectives or advantages or features disclosed in the present invention. In addition, the abstract and the title are only used to assist the search of patent documents, and are not used to limit the scope of rights of the present invention. In addition, terms such as "first" and "second" mentioned in this specification or the scope of the patent application are only used to name elements (elements) or to distinguish different embodiments or ranges, and are not used to limit the number of elements. upper or lower limit.

1: Keyboard device 10, 10a: key structure 101: keycap 102: elastic element 103a: Thin film circuit board 1021: around the wall 1022: ring bottom 1031: the first film substrate 1032, 1032a: thin film conduction module 10321: Second film substrate 10322: spacer substrate C1: the first conductive contact C2: Second conductive contact C3: The third conductive contact D: Outer diameter length D': inner diameter length D1, D1': length of the first outer diameter D2, D2': second outer diameter length F1: top surface F2: bottom surface G: Gap H: through hole L1: first metal line L2: second metal line P1: The first circuit pattern P2: Second circuit pattern R: projection area AA: line segment

FIG. 1 is a schematic diagram of the appearance and structure of a keyboard device according to an embodiment of the present invention. FIG. 2 is a three-dimensional schematic diagram of the button structure shown in FIG. 1 . FIG. 3 is a schematic cross-sectional view along line AA shown in FIG. 2 . FIG. 4 is an exploded schematic view of the key structure shown in FIG. 2 . FIG. 5 is a schematic cross-sectional view of a button structure according to another embodiment of the present invention.

10: Button structure

102: elastic element

103: Thin film circuit board

1021: around the wall

1022: ring bottom

1031: the first film substrate

1032:Thin film conduction module

10321: Second film substrate

10322: spacer substrate

C1: the first conductive contact

C2: Second conductive contact

C3: The third conductive contact

D: Outer diameter length

D1: Length of the first outer diameter

D2: second outer diameter long crossing

F1: top surface

F2: bottom surface

G: Gap

H: through hole

Claims (11)

A thin film circuit board is used for a key structure of a keyboard device, the key structure includes an elastic element, and the thin film circuit board includes: A first film substrate, including a first conductive contact and a second conductive contact disposed on a top surface, the elastic element projects vertically toward the first film substrate to form a projected area on the top surface, And the first conductive contact and the second conductive contact are located in the projected area; and A film conduction module, arranged between the elastic element and the first film substrate and located in the projection area, the film conduction module includes a third conductive contact, the first conductive contact and the second conductive contact The contacts correspond to the third conductive contacts respectively. The thin film circuit board according to claim 1, wherein the thin film conduction module includes a second thin film substrate and a spacer substrate stacked on top of each other, the second thin film substrate is located between the elastic element and the spacer substrate, the first thin film substrate The second film substrate has a bottom surface facing the first film substrate, the third conductive contact is disposed on the bottom surface, the spacer substrate is located between the first film substrate and the second film substrate, and the spacer substrate There is a distance between the first conductive contact and the second conductive contact and the third conductive contact respectively. The thin film circuit board according to claim 2, wherein the spacer substrate includes a through hole, the through hole is located between the first conductive contact of the first thin film substrate, the second conductive contact and the thin film conduction module. Between the third conductive contacts, in the conduction state, the third conductive contacts pass through the through holes and contact the first conductive contacts and the second conductive contacts. The thin film circuit board as claimed in claim 2, wherein the material of the first thin film substrate, the second thin film substrate and the spacer substrate is polyethylene terephthalate. The thin film circuit board as claimed in claim 2, wherein the elastic element includes a surrounding wall and an annular bottom, the surrounding wall extends toward the direction close to the first thin film substrate and is connected to the annular bottom, and the annular bottom faces the first thin film substrate A film substrate is vertically projected to form the projected area, and the annular bottom has an outer diameter length and an inner diameter length. The thin film circuit board as claimed in claim 5, wherein the second thin film substrate has a first outer diameter length, the spacer substrate has a second outer diameter length, the outer diameter length of the annular bottom, the first thin film substrate The length of the first outer diameter of the spacer substrate and the length of the second outer diameter of the spacer substrate are equal to each other. The thin film circuit board as claimed in item 5, wherein the second thin film substrate has a first outer diameter length, the spacer substrate has a second outer diameter length, and the first outer diameter length of the first thin film substrate is equal to the The second outer diameter length of the spacer substrate, and the first outer diameter length of the first film substrate and the second outer diameter length of the spacer substrate are respectively smaller than the inner diameter length of the annular bottom. The thin film circuit board as claimed in claim 1, wherein an area of the projected area of the elastic element formed on the first thin film substrate is smaller than a surface area of the top surface of the first thin film substrate. The thin film circuit board as claimed in claim 1, wherein the first thin film substrate further includes a first metal circuit and a second metal circuit, the first metal circuit is disposed on the top surface and extends from the first conductive contact and out of the projection area to one side, the second metal circuit is disposed on the top surface and extends from the second conductive contact to the other side outside the projection area. The thin film circuit board as claimed in claim 7, wherein at least one of the first metal circuit and the second metal circuit is a silver paste circuit. A keyboard device comprising Multiple button structures, each button structure includes: One key cap; an elastic element is arranged under the keycap; and A thin film circuit board is arranged under the elastic element, and the thin film circuit board includes: A first film substrate, including a first conductive contact and a second conductive contact disposed on a top surface, the elastic element projects vertically toward the first film substrate to form a projected area on the top surface, And the first conductive contact and the second conductive contact are located in the projected area; and A film conduction module, arranged between the elastic element and the first film substrate and located in the projection area, the film conduction module includes a third conductive contact, the first conductive contact and the second conductive contact The contacts correspond to the third conductive contacts respectively.

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