TWI772101B - Membrane circuit board - Google Patents

Abstract

The present invention discloses a membrane circuit board including a first membrane substrate, a second membrane substrate, a spacer substrate, a first circuit pattern and a second circuit pattern. The membrane substrate includes a first conductive contact. The second membrane substrate is disposed relative to the membrane substrate, and the second membrane substrate includes a second conductive contact. The spacer substrate is disposed between the first membrane substrate and the second membrane substrate. The spacer substrate includes a first surface and a second surface opposite to each other, the first surface faces to the first membrane substrate, and the second surface faces to the second membrane substrate. The first circuit pattern is disposed on the first surface of the spacer substrate and the first conductive contacts correspond to each other. The second circuit pattern is disposed on the second surface of the spacer substrate and corresponds to the second conductive contact.

Description

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. Therefore, how to make the operation of electronic equipment more humane 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 allows users to directly input characters and symbols to the computer, and thus has received considerable attention.

Most of the conventional keyboard devices include a key base plate, a thin-film circuit board, and a plurality of key structures. The thin-film circuit board includes a plurality of membrane switches, and the membrane switches correspond to the key structures respectively. Each key structure includes a keycap, a scissor-type connecting element and an elastic element. The scissors-type connecting element is connected between the keycap and the key bottom plate, and the scissor-type connecting element includes a first frame and a second frame that can swing relative to each other. , the elastic element is arranged between the key cap and the film circuit board, and the elastic element has a top. 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 connecting element will be changed from the open and closed state to the overlapping state, and the keys that move downward will The cap will squeeze the elastic element, so that the top of the elastic element is pressed against the top and trigger the corresponding membrane switch, so that the corresponding membrane switch can be electrically connected, and when the key cap of the key structure is no longer pressed At this time, the key cap will move upward relative to the key bottom plate according to the elastic force of the elastic element, at this time, the first frame and the second frame will change from the overlapping state to the opening and closing state, and the key cap will return to its original position.

Please refer to FIG. 1 , which is a schematic side view of a partial structure of a thin film circuit board of a conventional keyboard device. As shown in FIG. 1 , the thin-film circuit board 1 includes an upper-layer thin-film substrate 11 , a lower-layer thin-film substrate 12 , and a middle-layer thin-film substrate 13 interposed between the upper-layer thin-film substrate 11 and the lower-layer thin-film substrate 12 . The lower surface of the upper film substrate 11 has a first circuit pattern 110 , and the first circuit pattern 110 has a plurality of upper contacts 1101 and a plurality of silver glue lines 1102 respectively corresponding to the above-mentioned key structures. The upper surface of the lower film substrate 12 has a second circuit pattern 120 , and the second circuit pattern 120 has a plurality of lower contacts 1201 and a plurality of lower silver glue lines 1202 respectively corresponding to the upper contacts 1101 . In addition, the middle-layer thin film substrate 13 has a plurality of openings 130 corresponding to the upper contacts 1101 and the lower contacts 1201 respectively. Each of the above-mentioned upper contacts 1101 and its corresponding lower contacts 1201 together form the above-mentioned membrane switch.

However, due to the limitation of the circuit pattern printing process, the upper film substrate 11 and the lower film substrate 12 usually use thicker substrates, so that the first circuit pattern 110 and the second circuit pattern 120 can be smoothly printed on the upper layer. The lower surface of the thin film substrate 11 and the upper surface of the lower thin film substrate 12, but choosing the thicker upper thin film substrate 11 and the lower thin film substrate 12 will increase the overall thickness of the thin film circuit board 1, thereby making the keyboard device unable to achieve thinning. Purpose. Therefore, how to improve the above-mentioned problems is really the focus of the relevant personnel in the art.

One of the objects of the present invention is to provide a thin film wiring board.

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

To achieve one or part or all of the above objectives or other objectives, the present invention provides a thin film circuit board, which includes a first thin film substrate, a second thin film substrate, a spacer substrate, a first circuit pattern and a second circuit pattern. The first thin film substrate includes first conductive contacts. The second thin film substrate is disposed relative to the first thin film substrate, and the second thin film substrate includes second conductive contacts. The spacer substrate is disposed between the first thin film substrate and the second thin film substrate. The spacer substrate includes a first surface and a second surface opposite to each other, the first surface faces the first thin film substrate, and the second surface faces the second thin film substrate. The first circuit patterns are disposed on the first surface of the spacer substrate and the first conductive contacts correspond to each other. The second circuit patterns are disposed on the second surface of the spacer substrate and correspond to the second conductive contacts.

In an embodiment of the present invention, the first thin film substrate has a first thickness, the second thin film substrate has a second thickness, and the spacer substrate has a third thickness, and the first thickness and the second thickness are respectively smaller than the third thickness.

In an embodiment of the present invention, the spacer substrate includes a through hole, the through hole is located between the first conductive contact of the first thin film substrate and the second conductive contact of the second thin film substrate, and the through hole includes a through hole located on the first conductive contact of the first thin film substrate and the second conductive contact of the second thin film substrate. A first opening on a surface and a second opening on a second surface.

In an embodiment of the present invention, the above-mentioned first circuit pattern includes a first ring contact and a first metal circuit connected to each other, and the first ring contact is arranged on the first ring along the periphery of the first opening. on the surface, and the first metal line extends in a first direction away from the first annular contact.

In an embodiment of the present invention, the above-mentioned second circuit pattern includes a second ring contact and a second metal circuit connected to each other, and the second ring contact is along the circumference of the second opening. The edge is disposed on the second surface, and the second metal line extends in a second direction away from the second annular contact, and the second direction and the first direction are not parallel to each other.

In one embodiment of the present invention, the first thin film substrate further includes a bottom surface facing the spacer substrate, the second film substrate further includes a top surface facing the spacer substrate, and the first conductive contacts are disposed on the bottom surface to be connected with the first The first ring contacts of the circuit pattern correspond to each other, the second conductive contacts are disposed on the top surface and the second ring contacts of the second circuit pattern correspond to each other.

In an embodiment of the present invention, at least one of the first metal lines of the first circuit pattern and the second metal lines of the second circuit pattern is a silver paste line.

In an embodiment of the present invention, when the above-mentioned thin film circuit board is in a non-conducting state, there is a first distance between the first circuit pattern and the first conductive contact, and a distance between the second circuit pattern and the second conductive contact second spacing.

In an embodiment of the present invention, when the above-mentioned thin film circuit board is in a conducting state, the first circuit pattern contacts the first conductive contact, and the second circuit pattern contacts the second conductive contact.

In an embodiment of the present invention, the material of the first thin film substrate, the second thin film substrate and the spacer substrate is polyethylene terephthalate, and the thin film circuit board can be configured in the keyboard device.

The thin film circuit board of the embodiment of the present invention adopts a thicker spacer substrate, and the first circuit pattern and the second circuit pattern are respectively printed on the first surface and the second surface of the spacer substrate, and are located on the upper and lower sides of the spacer substrate. The first thin film substrate and the second thin film substrate only need to configure the first conductive contacts and the second conductive contacts respectively. Therefore, the first thin film substrate and the second thin film substrate can be made of thinner substrates. Under such a structural design, the overall thickness of the thin-film circuit board can be effectively reduced to achieve the purpose of thinning.

In order to make the above-mentioned and other objects, features and advantages of the present invention more clearly understood, preferred embodiments are hereinafter described in detail in conjunction with the accompanying drawings.

1, 2: Thin film circuit board

11: Upper film substrate

12: Lower film substrate

13: Middle layer thin film substrate

110, 24: The first circuit pattern

120, 25: Second circuit pattern

130: Opening

21: The first thin film substrate

22: Second thin film substrate

23: Spacer substrate

210: The first conductive contact

211: Bottom surface

220: The second conductive contact

221: Top surface

230: Through hole

231: First Surface

232: Second Surface

241: The first ring contact

242: First Metal Line

251: The second ring contact

252: Second metal line

D1: first direction

D2: Second direction

G1: first pitch

G2: Second Gap

H1: first opening

H2: Second opening

T1: first thickness

T2: Second thickness

T3: The third thickness

FIG. 1 is a schematic side view of a partial structure of a thin film circuit board of a conventional keyboard device.

2 is a schematic side view of a partial structure of a thin film circuit board in a non-conducting state according to an embodiment of the present invention.

FIG. 3 is a schematic side view of a part of the structure of the thin film circuit board shown in FIG. 2 in an on state.

FIG. 4 is a schematic bottom view of the first thin film substrate of the thin film circuit board shown in FIG. 2 .

FIG. 5 is a schematic top view of the second thin film substrate of the thin film circuit board shown in FIG. 2 .

FIG. 6 is a schematic top view of the spacer substrate of the thin film circuit board shown in FIG. 2 .

FIG. 7 is a schematic bottom view of the spacer substrate of the thin film circuit board shown in FIG. 2 .

Please refer to FIGS. 2 to 7 . FIG. 2 is a schematic side view of a partial structure of a thin film circuit board in a non-conducting state according to an embodiment of the present invention. FIG. 3 is a schematic side view of a part of the structure of the thin film circuit board shown in FIG. 2 in an on state. FIG. 4 is a schematic bottom view of the first thin film substrate of the thin film circuit board shown in FIG. 2 . FIG. 5 is a schematic top view of the second thin film substrate of the thin film circuit board shown in FIG. 2 . FIG. 6 is a schematic top view of the spacer substrate of the thin film circuit board shown in FIG. 2 . FIG. 7 is a schematic bottom view of the spacer substrate of the thin film circuit board shown in FIG. 2 .

As shown in FIGS. 2 to 7 , the thin film circuit board 2 of this embodiment includes a first thin film substrate 21 , a second thin film substrate 22 , a spacer substrate 23 , a first circuit pattern 24 and a second circuit pattern 25 . The first thin film substrate 21 includes first conductive contacts 210 . The second thin film substrate 22 phases It is configured for the first thin film substrate 21 , and the second thin film substrate 22 includes a second conductive contact 220 . The spacer substrate 23 is disposed between the first thin film substrate 21 and the second thin film substrate 22 . The spacer substrate 23 includes a first surface 231 and a second surface 232 opposite to each other. The first surface 231 of the spacer substrate 23 faces the first thin film substrate 21 , and the second surface 232 faces the second thin film substrate 22 . The first circuit patterns 24 are disposed on the first surface 231 of the spacer substrate 23 , and the first circuit patterns 24 and the first conductive contacts 210 of the first thin film substrate 21 correspond to each other. The second circuit patterns 25 are disposed on the second surface 232 of the spacer substrate 23 , and the second circuit patterns 25 and the second conductive contacts 220 of the second thin film substrate 22 correspond to each other.

The detailed structure of the thin film circuit board 2 according to the embodiment of the present invention will be further described below.

As shown in FIGS. 2 , 3 , 6 and 7 , the spacer substrate 23 of this embodiment includes through holes 230 . The through hole 230 is located between the first conductive contact 210 of the first thin film substrate 21 and the second conductive contact 220 of the second thin film substrate 22 . In this embodiment, the through hole 230 penetrates from the first surface 231 to the second surface 232 of the spacer substrate 23 , and then the first opening H1 is formed on the first surface 231 of the spacer substrate 23 and the first opening H1 is formed on the second surface 232 of the spacer substrate 23 . The two openings H2, the first opening H1 and the second opening H2 correspond to the first conductive contact 210 and the second conductive contact 220 respectively.

As shown in FIG. 6 , the first circuit pattern 24 in this embodiment includes a first ring contact 241 and a first metal line 242 which are connected to each other. The first annular contact 241 of the first circuit pattern 24 is disposed on the first surface 231 of the spacer substrate 23 along the periphery of the first opening H1 of the spacer substrate 23 , and the first metal line 242 faces away from the first annular The first direction D1 of the contact point 241 extends. In this embodiment, the first metal line 242 is, for example, a silver paste line, but the invention is not limited thereto.

As shown in FIG. 7 , the second circuit pattern 25 of this embodiment includes a second ring contact 251 and a second metal line 252 which are connected to each other. The second ring contact 251 of the second circuit pattern 25 is disposed on the second surface 232 of the spacer substrate 23 along the periphery of the second opening H2 of the spacer substrate 23 , and the second metal line 252 faces away from the second ring contact 251 extends in the second direction D2, and the second direction D2 in which the second metal line 252 extends and the first direction D1 in which the first metal line 242 extends are not parallel to each other. For example, the two directions D2 and the first direction D1 in which the first metal lines 242 extend are perpendicular to each other, but the invention is not limited to this. In this embodiment, the second metal line 252 is, for example, a silver paste line, but the invention is not limited thereto.

It should be noted that the present invention does not limit the shapes of the first annular contact 241 and the second annular contact 251. In other embodiments, the first annular contact 241 and the second annular contact 251 The shape of the spacer substrate 23 can be changed to other shapes of contacts according to the shapes of the first opening H1 and the second opening H2 of the spacer substrate 23 .

As shown in FIG. 2 to FIG. 5 , the first thin film substrate 21 of the present embodiment further includes a bottom surface 211 facing the spacer substrate 23 . The second thin film substrate 22 further includes a top surface 221 facing the spacer substrate 23 . The first conductive contact 210 is disposed on the bottom surface 211 of the first thin film substrate 21 and corresponds to the first annular contact 241 of the first circuit pattern 24 . The second conductive contact 220 is disposed on the top surface 221 of the second thin film substrate 22 and corresponds to the second annular contact 251 of the second circuit pattern 25 .

As shown in FIG. 2 and FIG. 3 , the first thin film substrate 21 in this embodiment has a first thickness T1 , the second thin film substrate 22 has a second thickness T2 , and the spacer substrate 23 has a third thickness T3 . In this embodiment, the first thickness T1 of the first thin film substrate 21 and the second thickness T2 of the second thin film substrate 22 are respectively smaller than the third thickness T3 of the spacer substrate 23 . Compared with the conventional thin-film circuit board structure (please refer to FIG. 1 ), since the conventional thin-film circuit board 1 combines the first circuit pattern 110 with the first circuit pattern 110 . The two circuit patterns 120 are respectively arranged on the upper layer film substrate 11 and the lower layer film substrate 12, so the upper layer film substrate 11 and the lower layer film substrate 12 must be made of thicker substrates to have sufficient structural strength to configure the circuit patterns, which results in The overall thickness of the conventional thin film circuit board 1 is increased. In contrast, in the thin film circuit board 2 of the present embodiment, both the first circuit pattern 24 and the second circuit pattern 25 are arranged on the thicker spacer substrate 23, and the first thin film substrate Only the first conductive contacts 210 and the second conductive contacts 220 need to be arranged on the 21 and the second thin film substrate 22 respectively, so the first thin film substrate 21 and the second thin film substrate 22 can be made of thinner substrates, which can effectively reduce the film The overall thickness of the circuit board 2 achieves the purpose of thinning.

It should be noted that the materials of the first film substrate 21 , the second film substrate 22 and the spacer substrate 23 in this embodiment are, for example, polyethylene terephthalate (PET), but the present invention does not This is the limit. In this embodiment, the first circuit pattern 24 and the second circuit pattern 25 are respectively formed on the bottom surface 211 of the first thin film substrate 21 and the top surface 221 of the second thin film substrate 22 according to a specified shape by printing, but the present invention Not limited to this. The thin film circuit board 2 of this embodiment can be configured on an external keyboard (eg, a PS2 interface keyboard or a USB interface keyboard) used in a desktop computer, a built-in keyboard used in a notebook computer or a laptop computer, However, the present invention is not limited to this, that is, the concept of the thin film circuit board 2 of the embodiment of the present invention can be applied to any electronic product using the thin film circuit board 2 as a signal input interface.

Specifically, the thin-film circuit board 2 of this embodiment is disposed below a plurality of key structures (not shown) in the keyboard device. Generally speaking, the key structure includes elements such as a key cap, a scissor-type connection assembly, an elastic member, and the like, and the connection relationship between these elements is not described here. A plurality of membrane switches may be formed between the first circuit pattern 24 , the second circuit pattern 25 , the first conductive contact 210 and the second conductive contact 220 of the thin film circuit board 2 , that is, a plurality of the first circuit patterns 24 . A ring contact 241 , a plurality of second ring contacts of the second circuit pattern 25 251 , the plurality of first conductive contacts 210 and the plurality of second conductive contacts 220 form these membrane switches, and these membrane switches are located below the corresponding key structures respectively.

As shown in FIG. 2 , when the key cap of the key structure is not pressed, the thin film circuit board 2 is in a non-conducting state, and there is a connection between the first ring contact 241 of the first circuit pattern 24 and the first conductive contact 210 . For the first distance G1, there is a second distance G2 between the second annular contact 251 of the second circuit pattern 25 and the second conductive contact 220. As shown in FIG. 3 , when the key cap of the key structure is pressed to move toward the thin film circuit board 2 , the key cap will directly or indirectly push the first thin film substrate 21 and the spacer substrate 23 to move toward the direction close to the second thin film substrate 22 , so that the first ring contact 241 of the first circuit pattern 24 is in contact with the first conductive contact 210 and the second ring contact 251 of the second circuit pattern 25 is contacted with the second conductive contact 220, thereby making the thin film circuit board 2 is in a conducting state and immediately generates a trigger signal corresponding to the pressed key structure.

To sum up, in the thin film circuit board of the embodiment of the present invention, a spacer substrate with a thicker thickness is used, and the first circuit pattern and the second circuit pattern are printed on the first surface and the second surface of the spacer substrate respectively, and are located on the spacer substrate. The first thin film substrate and the second thin film substrate on the upper and lower sides of the spacer substrate only need to be respectively provided with the first conductive contacts and the second conductive contacts. Therefore, the first thin film substrate and the second thin film substrate can be selected with thinner thicknesses. Under such a structural design, the overall thickness of the thin film circuit board can be effectively reduced to achieve the purpose of thinning.

However, the above are only preferred embodiments of the present invention, and should not limit the scope of the present invention, that is, any simple equivalent changes and modifications made according to the scope of the patent application of the present invention and the contents of the description of the invention, All still fall within the scope of the patent of the present invention. In addition, any embodiment of the present invention or the scope of the claims is not required to achieve all of the objects or advantages or features disclosed herein. In addition, the abstract section and the title are only used to aid the search of patent documents and are not intended to limit the scope of the present invention. In addition, this manual or application The terms such as "first" and "second" mentioned in the scope of the patent are only used to name the elements or to distinguish different embodiments or ranges, and are not used to limit the upper or lower limit of the number of elements.

2: Thin film circuit board

21: The first thin film substrate

22: Second thin film substrate

23: Spacer substrate

24: The first circuit pattern

25: Second circuit pattern

210: The first conductive contact

211: Bottom surface

220: The second conductive contact

221: Top surface

230: Through hole

231: First Surface

232: Second Surface

241: The first ring contact

251: The second ring contact

G1: first pitch

G2: Second Gap

H1: first opening

H2: Second opening

T1: first thickness

T2: Second thickness

T3: The third thickness

Claims (7)

A thin film circuit board, comprising: a first thin film substrate including a first conductive contact; a second thin film substrate disposed relative to the first thin film substrate, and the second thin film substrate including a second conductive contact; A spacer substrate is disposed between the first film substrate and the second film substrate, the spacer substrate includes a first surface and a second surface opposite to each other, the first surface faces the first film substrate, the first surface Two surfaces face the second thin film substrate, and the spacer substrate includes a through hole located between the first conductive contact of the first thin film substrate and the second conductive contact of the second thin film substrate, And the through hole includes a first opening located on the first surface and a second opening located on the second surface; a first circuit pattern is arranged on the first surface of the spacer substrate and is connected to the first conductive The contacts correspond to each other, wherein the first circuit pattern includes a first ring contact and a first metal circuit connected to each other, the first ring contact is arranged along the periphery of the first opening on the on the first surface, and the first metal circuit extends in a first direction away from the first ring contact; and a second circuit pattern is disposed on the second surface of the spacer substrate, and is connected with the second The conductive contacts correspond to each other, wherein the second circuit pattern includes a second ring contact and a second metal circuit connected to each other, the second ring contact is arranged along the periphery of the second opening on the first On the two surfaces, the second metal line extends in a second direction away from the second ring contact, and the second direction and the first direction are not parallel to each other. The thin film circuit board of claim 1, wherein the first thin film substrate has a first thickness, the second thin film substrate has a second thickness, the spacer substrate has a third thickness, and the first thickness is the same as the first thickness. The second thicknesses are respectively smaller than the third thickness. The thin film circuit board of claim 1, wherein the first thin film substrate further includes a bottom surface facing the spacer substrate, the second film substrate further includes a top surface facing the spacer substrate, and the first conductive contacts The first ring contacts of the first circuit pattern are arranged on the bottom surface and correspond to each other, the second conductive contacts are arranged on the top surface and the second ring contacts of the second circuit pattern are mutually corresponding correspond. The thin film circuit board of claim 1, wherein at least one of the first metal circuit of the first circuit pattern and the second metal circuit of the second circuit pattern is a silver paste circuit. The thin film circuit board as claimed in claim 1, wherein in a non-conducting state, there is a first distance between the first circuit pattern and the first conductive contact, and the second circuit pattern and the second conductive contact There is a second spacing between the dots. The thin-film circuit board of claim 1, wherein in an on state, the first circuit pattern contacts the first conductive contact, and the second circuit pattern contacts the second conductive contact. The thin film circuit board of claim 1, wherein the material of the first thin film substrate, the second thin film substrate and the spacer substrate is polyethylene terephthalate, and the thin film circuit board can be configured on a keyboard device middle.

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