Thin-film circuit boards and their keyboard devices

Abstract

This invention provides a thin-film circuit board and a keyboard device thereof. The thin-film circuit board is used in the key structure of the keyboard device, and the key structure includes an elastic element. The thin-film circuit board includes a first thin-film substrate and a second thin-film substrate. The first thin-film substrate includes a first conductive contact and a second conductive contact disposed on its top surface. The elastic element is projected perpendicularly toward the first thin-film substrate to form a projection area on the top surface, and the first conductive contact and the second conductive contact are located within the projection area. A thin-film conductive module is disposed between the elastic element and the first thin-film substrate and is located within the projection area. The thin-film conductive module includes a third conductive contact, and the first conductive contact and the second conductive contact respectively correspond to each other with the third conductive contact.

Description

Technical Field

[0001] This invention relates to the field of input devices, and more particularly to a thin-film circuit board for use in keyboard devices. Background Technology

[0002] With the rapid development of technology and the booming development of electronic devices, many conveniences have been brought to human life. Therefore, making the operation of electronic devices more user-friendly is an important issue. Common input devices for electronic devices include mice, keyboards, and trackballs. Among them, keyboards allow users to directly input text and symbols into the computer, and are therefore highly valued.

[0003] The keyboard device includes multiple key structures. Each key structure mainly includes keycaps stacked sequentially, a scissor-switch connector, a membrane circuit board, and a key base plate. If it is an illuminated keyboard, a backlight module is additionally located below the key base plate. Specifically, the membrane circuit board has a membrane switch, and an elastic element is disposed between the keycap and the membrane circuit board. The scissor-switch connector connects the keycap and the key base plate and includes a first frame and a second frame pivotally connected to the first frame, allowing the first and second frames to swing relative to each other. When a keycap of any key structure is pressed and moves downward relative to the key base plate, the first and second frames of the scissor-switch connector change from an open state to a stacked state. The downward-moving keycap compresses the elastic element, causing the elastic element to abut and trigger the corresponding membrane switch, thus generating a corresponding key signal. When the keycaps of the key structure are no longer pressed, they will move upward relative to the key base plate according to the elastic restoring force of the elastic element. At this time, the first frame and the second frame will change from the overlapping state to the open state, and the keycaps will return to their original positions.

[0004] A known thin-film circuit board for a keyboard device includes an upper thin-film substrate, a lower thin-film substrate, and a middle thin-film substrate situated between the upper and lower thin-film substrates. The lower surface of the upper thin-film substrate has a first circuit pattern, which includes multiple upper contacts and multiple upper silver paste lines corresponding to the aforementioned key structures. The upper surface of the lower thin-film substrate has a second circuit pattern, which includes multiple lower contacts and multiple lower silver paste lines corresponding to the upper contacts. Furthermore, the middle thin-film substrate has multiple openings corresponding to the upper and lower contacts. Each upper contact and its corresponding lower contact together form the aforementioned membrane switch.

[0005] However, conventional thin-film circuit boards are constructed by stacking upper, lower, and middle thin-film substrates of roughly the same size (e.g., same surface area). This structural design makes it impossible to achieve a thinner keyboard device. Therefore, how to improve upon these issues is a focus of attention for those skilled in the art. Summary of the Invention

[0006] One of the objectives of this invention is to provide a thin film circuit board.

[0007] Another object of the present invention is to provide a keyboard device having a thin film circuit board.

[0008] Other objects and advantages of the present invention can be further understood from the technical features disclosed herein.

[0009] To achieve one, some, or all of the above-mentioned objectives, or other objectives, the present invention provides a thin-film circuit board for a key structure of a keyboard device, the key structure including an elastic element. The thin-film circuit board includes a first thin-film substrate and a thin-film conductive module. The first thin-film substrate includes a first conductive contact and a second conductive contact disposed on its top surface. The elastic element is projected perpendicularly toward the first thin-film substrate to form a projection area on the top surface, and the first conductive contact and the second conductive contact are located within the projection area. The thin-film conductive module is disposed between the elastic element and the first thin-film substrate and is located within the projection area. The thin-film conductive module includes a third conductive contact, with the first and second conductive contacts respectively corresponding to the third conductive contact.

[0010] In one embodiment of the present invention, the thin film conductive 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 second thin film substrate has a bottom surface facing the first thin film substrate. A third conductive contact is disposed on the bottom surface. The spacer substrate is located between the first thin film substrate and the second thin film substrate, and the spacer substrate makes the first conductive contact and the second conductive contact have a spacing distance from the third conductive contact.

[0011] In one embodiment of the present invention, the aforementioned spacer substrate includes a through hole. The through hole is located between a first conductive contact and a second conductive contact of the first thin film substrate and a third conductive contact of the thin film conductive module. In the conductive state, the third conductive contact passes through the through hole and contacts the first conductive contact and the second conductive contact.

[0012] In one embodiment of the present invention, the first thin film substrate, the second thin film substrate and the spacer substrate are made of polyethylene terephthalate.

[0013] In one embodiment of the present invention, the above-mentioned elastic element includes a surrounding wall and an annular bottom. The surrounding wall extends toward the first thin film substrate and is connected to the annular bottom. The annular bottom is projected perpendicularly toward the first thin film substrate to form a projection area, and the annular bottom has an outer diameter length and an inner diameter length.

[0014] In one embodiment of the present invention, the second thin film substrate has a first outer diameter length, the spacer substrate has a second outer diameter length, and the outer diameter length of the annular bottom, the first outer diameter length of the first thin film substrate, and the second outer diameter length of the spacer substrate are equal to each other.

[0015] In one embodiment of the present invention, the second thin film substrate has a first outer diameter length, the spacer substrate has a second outer diameter length, the first outer diameter length of the first thin film substrate is equal to the second outer diameter length of the spacer substrate, and the first outer diameter length of the first thin film substrate and the second outer diameter length of the spacer substrate are respectively smaller than the inner diameter length of the annular bottom.

[0016] In one embodiment of the present invention, the area of ​​the projection region formed by the elastic element on the first thin film substrate is smaller than the surface area of ​​the top surface of the first thin film substrate.

[0017] In one embodiment of the present invention, the first thin film substrate further includes a first metal line and a second metal line. The first metal line is disposed on the top surface and extends from the first conductive contact to one side outside the projection area, and the second metal line is disposed on the top surface and extends from the second conductive contact to the other side outside the projection area.

[0018] In one embodiment of the present invention, at least one of the first metal line and the second metal line described above is a silver paste line.

[0019] The present invention also provides a keyboard device, including multiple key structures, each key structure including a keycap, an elastic element, and a thin-film circuit board. The elastic element is disposed below the keycap. The thin-film circuit board is disposed below the elastic element. The thin-film circuit board includes a first thin-film substrate and a thin-film conductive module. The first thin-film substrate includes a first conductive contact and a second conductive contact disposed on its top surface. The elastic element is projected perpendicularly toward the first thin-film substrate to form a projection area on the top surface, and the first conductive contact and the second conductive contact are located within the projection area. The thin-film conductive module is disposed between the elastic element and the first thin-film substrate and is located within the projection area. The thin-film conductive module includes a third conductive contact, with the first conductive contact and the second conductive contact respectively corresponding to the third conductive contact.

[0020] In this embodiment of the thin-film circuit board, the size of the first thin-film substrate is different from the size of the thin-film conductive module formed by the second thin-film substrate and the spacer substrate. In this embodiment, both the second thin-film substrate and the spacer substrate are located within the vertical projection range of the elastic element onto the first thin-film substrate. That is, the outer diameter of the second thin-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 thin-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 this structural design, the overall thickness of the thin-film circuit board is actually only the thickness of the first thin-film substrate. In this way, the overall thickness of the thin-film circuit board is effectively reduced, achieving the purpose of thinning.

[0021] To make the above and other objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the external structure of a keyboard device according to an embodiment of the present invention.

[0023] Figure 2 for Figure 1 The diagram shows a three-dimensional structure of the button.

[0024] Figure 3 For along Figure 2 The diagram shows a cross-sectional view of line segment AA.

[0025] Figure 4 for Figure 2 The diagram shows an exploded view of the button structure.

[0026] Figure 5 This is a cross-sectional schematic diagram of the button structure according to another embodiment of the present invention.

[0027] The attached figures are labeled as follows:

[0028] 1: Keyboard device

[0029] 10, 10a: Key structure

[0030] 101: Keycaps

[0031] 102: Elastic element

[0032] 103a: Thin-film circuit board

[0033] 1021: Surrounding the Wall

[0034] 1022: Circular bottom

[0035] 1031: First thin film substrate

[0036] 1032, 1032a: Thin-film conduction module

[0037] 10321: Second thin film substrate

[0038] 10322: Spacer substrate

[0039] C1: First conductive contact

[0040] C2: Second conductive contact

[0041] C3: Third conductive contact

[0042] D: Outer diameter length

[0043] D': Inner diameter length

[0044] D1, D1': First outer diameter length

[0045] D2, D2': Second outer diameter length

[0046] F1: Top surface

[0047] F2: Bottom surface

[0048] G: Gap

[0049] H: Through hole

[0050] L1: First metal circuit

[0051] L2: Second metal circuit

[0052] P1: First circuit diagram

[0053] P2: Second circuit diagram

[0054] R: Projection area

[0055] AA: line segment Detailed Implementation

[0056] Please see Figures 1 to 4 , Figure 1 This is a schematic diagram of the external structure of a keyboard device according to an embodiment of the present invention. Figure 2 for Figure 1 The diagram shows a three-dimensional structure of the button. Figure 3 For along Figure 2 The diagram shows a cross-sectional view of line segment AA. Figure 4 for Figure 2 The diagram shows an exploded view of the button structure. For a clearer illustration, Figures 2 to 4 Only a single button structure and its related components are shown.

[0057] like Figures 1 to 4As shown, the keyboard device 1 of this embodiment includes a plurality of key structures 10. Each key structure 10 includes a keycap 101, an elastic element 102, and a membrane 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 membrane circuit board 103. In this embodiment, these key structures 10 can be classified as general keys, number keys, function keys, etc., which are used by the user to press with their fingers to cause the keyboard device 1 to generate corresponding key input signals to the computer, thereby causing the computer to perform corresponding functions. For example, general keys are used to input symbols such as English letters, number keys are used to input numbers, and function keys are used to provide various shortcut functions, such as F1 to F12, or larger and longer space keys or shift keys. It should be noted that, in order to clearly express the connection relationship between the elastic element 102 and the membrane circuit board 103, therefore Figures 2 to 4 Omitted Figure 1 The keycap 101 shown is the component.

[0058] It should be noted that, in this embodiment, the thin-film circuit board 103 is disposed in the keyboard device 1 on multiple key structures 10 (e.g., ...). Figure 1 (As shown below). Generally speaking, in addition to the keycap 101, elastic element 102 and membrane circuit board 103 mentioned above, the key structure 10 also includes scissor-type connecting components and key base plate, etc. However, these components are not the focus of this invention, and the connection relationship between these components and other components is known technology, so they will not be described in detail here.

[0059] like Figures 2 to 4 As shown, the thin-film circuit board 103 of this embodiment includes a first thin-film substrate 1031 and a thin-film conductive module 1032. The first thin-film substrate 1031 includes a first conductive contact C1 and a second conductive contact C2 disposed on the top surface F1. In this embodiment, an elastic element 102 located above the thin-film circuit board 103 is projected vertically toward the first thin-film substrate 1031 to form a projection area R on the top surface F1. The first conductive contact C1 and the second conductive contact C2 of the first thin-film substrate 1031 are both located within the projection area R. The thin-film conductive module 1032 is disposed between the elastic element 102 and the first thin-film substrate 1031, and the thin-film conductive module 1032 is located within the projection area R. 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 thin-film substrate 1031 correspond to the third conductive contact C3 of the thin-film conduction module 1032, and the first conductive contact C1, the second conductive contact C2 and the third conductive contact C3 form a thin-film switch.

[0060] like Figures 2 to 4As shown, the thin-film conductive module 1032 of this embodiment includes a second thin-film substrate 10321 and a spacer substrate 10322. The second thin-film substrate 10321 and the spacer substrate 10322 are stacked on top of each other. The second thin-film substrate 10321 is located between the elastic element 102 and the spacer substrate 10322, and the second thin-film substrate 10321 has a bottom surface F2 facing the first thin-film substrate 1031. The third conductive contact C3 of the thin-film conductive module 1032 is disposed on the bottom surface F2 of the second thin-film substrate 10321. The spacer substrate 10322 is located between the first thin-film substrate 1031 and the second thin-film substrate 10321, and the spacer substrate 10322 provides a spacing between the first conductive contact C1, the second conductive contact C2 located on the first thin-film substrate 1031, and the third conductive contact C3 located on the second thin-film substrate 10321.

[0061] It should be noted that the projection area R formed by the elastic element 102 on the top surface F1 of the first thin film substrate 1031 includes the space directly above the projection area R. Therefore, the second thin film substrate 10321 and the spacer substrate 10322 of the thin film conduction module 1032 are both located within this projection area R. That is, the maximum surface area of ​​the second thin film substrate 10321 and the spacer substrate 10322 is less than or equal to the area of ​​the projection area R. Furthermore, in this embodiment, the area of ​​the projection area R formed by the elastic element 102 on the top surface F1 of the first thin film substrate 1031 is less than the surface area of ​​the top surface F1 of the first thin film substrate 1031. With this structural design, when the thin-film conductive module 1032 and the elastic element 102 are assembled together, the thin-film conductive module 1032 and the elastic element 102 will present an integral appearance. Therefore, when the thin-film conductive module 1032 and the elastic element 102 are arranged on the first thin-film substrate 1031, the overall thickness of the thin-film circuit board 103 is actually only the thickness of the first thin-film substrate 1031, effectively reducing the overall thickness of the thin-film circuit board 103 and achieving the purpose of thinning.

[0062] like Figures 2 to 4 As shown, the spacer substrate 10322 in this embodiment includes a through hole H. The through hole H is located between the first conductive contact C1 and the second conductive contact C2 of the first thin film substrate 1031 and the third conductive contact C3 of the thin film conductive module 1032. In the conductive 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.

[0063] like Figure 2 , Figure 4As shown, the first thin-film substrate 1031 in 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 forms a first circuit pattern P1 with a first conductive contact C1. The first metal line L1 extends from the first conductive contact C1 to one side outside the projection area R. The second metal line L2 is disposed on the top surface F1 and forms a second circuit pattern P2 with a second conductive contact C2. That is, the second metal line L2 extends from the second conductive contact C2 to the other side of the projection area R. Since there is a gap G between the first conductive contact C1 and the second conductive contact C2, the first circuit pattern P1 and the second circuit pattern P2 are in an open circuit state when not conducting. In this embodiment, the first metal line L1 and the second metal line L2 are, for example, silver paste lines, but the present invention is not limited thereto.

[0064] It should be noted that the materials of the first thin-film substrate 1031, the second thin-film substrate 10321, and the spacer substrate 10322 in this embodiment are, for example, polyethylene terephthalate (PET), but the present invention is not limited thereto. The first circuit pattern P1 and the second circuit pattern P2 in this embodiment are, for example, formed on the top surface F1 of the first thin-film substrate 1031 by printing according to a specified shape, but the present invention is not limited thereto. The thin-film circuit board 103 of this embodiment can be configured in external keyboards used in desktop computers (e.g., PS / 2 interface keyboards, USB interface keyboards, or mechanical keyboards), built-in keyboards used in laptops or notebook computers, but the present invention is not limited thereto. That is, the concept of the thin-film circuit board 103 of this embodiment can be applied to any electronic product that uses the thin-film circuit board 103 as a signal input interface.

[0065] like Figures 2 to 4As shown, the elastic element 102 of this embodiment includes a surrounding wall 1021 and an annular bottom 1022. The surrounding wall 1021 extends toward the first thin film substrate 1031 and is connected to the annular bottom 1022. The annular bottom 1022 of the elastic element 102 is projected perpendicularly toward the first thin film substrate 1031 to form the aforementioned projection region R on the top surface F1. Specifically, the projection region R is the vertical projection of the opening of the annular bottom 1022 of the elastic element 102 toward the first thin film substrate 1031 onto the top surface F1 of the first thin film substrate 1031. Furthermore, the annular bottom 1022 of the elastic element 102 has an outer diameter length D. In this embodiment, the second thin film substrate 10321 of the thin film conduction module 1032 has a first outer diameter length D1, the spacer substrate 10322 has a second outer diameter length D2, and the first outer diameter length D1 of the second thin film substrate 10321, the second outer diameter length D2 of the spacer substrate 10322 and the outer diameter length D of the annular bottom 1022 of the elastic element 102 are all equal to each other.

[0066] Please see Figure 5 This is a cross-sectional schematic diagram of a button structure according to another embodiment of the present invention. Figure 5 As shown, the button structure 10a in this embodiment and Figures 2 to 4 The button structure 10 shown is similar, except that the thin-film conduction module 1032a of the thin-film circuit board 103a in this embodiment has the same dimensions as... Figures 2 to 4 The thin-film conductive module 1032 shown has different dimensions. In this embodiment, the annular bottom 1022 of the elastic element 102 has an inner diameter length D', while the first outer diameter length D1' of the second thin-film substrate 10321 of the thin-film conductive module 1032a is equal to the second outer diameter length D2' of the spacer substrate 10322. The first outer diameter length D1' of the second thin-film substrate 10321 and the second outer diameter length D2' of the spacer substrate 10322 are both smaller than the inner diameter length D' of the annular bottom 1022 of the elastic element 102. Under this structural design, the thin-film conductive module 1032a is located within the accommodating space defined by the surrounding wall 1021 and the annular bottom 1022.

[0067] In summary, the thin-film circuit board of this embodiment uses a different size for the first thin-film substrate than the thin-film conductive module formed by the second thin-film substrate and the spacer substrate. In this embodiment, both the second thin-film substrate and the spacer substrate are located within the vertical projection range of the elastic element onto the first thin-film substrate. That is, the outer diameter of the second thin-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 thin-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 this structural design, the overall thickness of the thin-film circuit board is actually only the thickness of the first thin-film substrate. In this way, the overall thickness of the thin-film circuit board is effectively reduced, achieving the purpose of thinning.

[0068] However, the above description is merely a preferred embodiment of the present invention and should not be construed as limiting the scope of the invention. Any simple equivalent changes and modifications made in accordance with the claims and description of the invention are still within the scope of this patent. Furthermore, no embodiment or claim of the present invention needs to achieve all the objectives, advantages, or features disclosed in the invention. In addition, the abstract and headings are merely for assisting in patent document searches and are not intended to limit the scope of the invention. Moreover, the terms "first," "second," etc., mentioned in this specification or claims are only used to name elements or distinguish different embodiments or scopes, and are not used to limit the upper or lower limit of the number of elements.

Claims

1. A thin-film circuit board for a key structure of a keyboard device, the key structure including a spring element, the thin-film circuit board comprising: A first thin-film substrate includes a first conductive contact and a second conductive contact disposed on a top surface. An elastic element is projected perpendicularly toward the first thin-film substrate to form a projection area on the top surface, and the first conductive contact and the second conductive contact are located within the projection area; and A thin-film conductive module is disposed between the elastic element and the first thin-film substrate and located in the projection area. The thin-film conductive module includes a third conductive contact, and the first conductive contact and the second conductive contact are respectively opposite to the third conductive contact. The thin-film conductive 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 second thin-film substrate has a bottom surface facing the first thin-film substrate. The third conductive contact is disposed on the bottom surface. The spacer substrate is located between the first thin-film substrate and the second thin-film substrate, and the spacer substrate makes the first conductive contact and the second conductive contact have a distance between them and the third conductive contact.

2. The thin-film circuit board as claimed in claim 1, wherein the thin-film circuit board includes a conductive state and a non-conductive state, wherein the spacer substrate includes a through hole, the through hole being located between the first conductive contact and the second conductive contact of the first thin-film substrate and the third conductive contact of the thin-film conductive module, and in the conductive state, the third conductive contact passes through the through hole and contacts the first conductive contact and the second conductive contact.

3. The thin-film circuit board as claimed in claim 1, wherein the first thin-film substrate, the second thin-film substrate and the spacer substrate are made of polyethylene terephthalate.

4. The thin-film circuit board of claim 1, wherein the elastic element includes a surrounding wall and an annular bottom, the surrounding wall extending toward the first thin-film substrate and connected to the annular bottom, the annular bottom being projected perpendicularly toward the first thin-film substrate to form the projection area, and the annular bottom having an outer diameter length and an inner diameter length.

5. The thin-film circuit board of claim 4, wherein the second thin-film substrate has a first outer diameter length, the spacer substrate has a second outer diameter length, and the outer diameter length of the annular bottom, the first outer diameter length of the first thin-film substrate, and the second outer diameter length of the spacer substrate are equal to each other.

6. The thin-film circuit board of claim 4, wherein the second thin-film substrate has a first outer diameter length, the spacer substrate has a second outer diameter length, the first outer diameter length of the first thin-film substrate is equal to the second outer diameter length of the spacer substrate, and the first outer diameter length of the first thin-film substrate and the second outer diameter length of the spacer substrate are respectively less than the inner diameter length of the annular bottom.

7. The thin-film circuit board of claim 1, wherein the area of ​​a region of the projection area formed by the elastic element on the first thin-film substrate is smaller than the surface area of ​​the top surface of the first thin-film substrate.

8. The thin-film circuit board of claim 1, wherein the first thin-film substrate further comprises a first metal line and a second metal line, the first metal line being disposed on the top surface and extending from the first conductive contact to one side outside the projection area, and the second metal line being disposed on the top surface and extending from the second conductive contact to the other side outside the projection area.

9. The thin-film circuit board of claim 8, wherein at least one of the first metal line and the second metal line is a silver paste line.

10. A keyboard device, comprising Multiple button structures, each button structure including: One-click cap; A flexible element is disposed below the keycap; as well as A thin-film circuit board is disposed below the elastic element, the thin-film circuit board comprising: A first thin-film substrate includes a first conductive contact and a second conductive contact disposed on a top surface. An elastic element is projected perpendicularly toward the first thin-film substrate to form a projection area on the top surface, and the first conductive contact and the second conductive contact are located within the projection area; and A thin-film conductive module is disposed between the elastic element and the first thin-film substrate and located in the projection area. The thin-film conductive module includes a third conductive contact, and the first conductive contact and the second conductive contact are respectively opposite to the third conductive contact. The thin-film conductive 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 second thin-film substrate has a bottom surface facing the first thin-film substrate. The third conductive contact is disposed on the bottom surface. The spacer substrate is located between the first thin-film substrate and the second thin-film substrate, and the spacer substrate makes the first conductive contact and the second conductive contact have a distance between them and the third conductive contact.

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