Key structure

Abstract

A key structure comprises a key cap, a connecting assembly and a circuit board. One end of the connecting assembly is connected to the keycap. The circuit board comprises an upper-layer film, a middle-layer substrate, a lower-layer film and a clamping hook. The middle substrate comprises a first insulating surface and a second insulating surface which are opposite to each other. The first insulating surface is connected with the upper film. The lower film is connected with the second insulating surface of the middle substrate. The hook is at least connected with the middle substrate. The clamping hook penetrates through the upper layer film and extends in the direction of the key cap. The other end of the connecting assembly is connected to the clamping hook.

Description

Technical Field

[0001] The invention relates to a key structure, in particular to a key structure applied to a membrane keyboard. Background Art

[0002] In terms of current computer usage habits, the keyboard is one of the indispensable input devices. Whether it is the computer itself or its peripheral products, they are all developing towards the design concept of light, thin, short and small. The keyboard has also changed from the early large structure to a thin keyboard. Thin keyboards usually use a membrane circuit board, also known as a membrane keyboard. The main components of a membrane keyboard include a base plate, a membrane circuit board and keys. Generally speaking, the membrane circuit board is arranged above the base plate. The keys mainly include a connecting component and a keycap. The base plate has a hook for connecting the components. Therefore, one end of the connecting component is connected to the keycap, and the other end is connected to the hook on the base plate. When the key is pressed, the membrane circuit board can be triggered to generate a corresponding trigger signal.

[0003] Since the bottom plate is a component for connecting and supporting the keys, the bottom plate is often made of a metal member with high strength, such as a metal plate. However, the use of the bottom plate makes the overall weight of the keyboard heavier and also has a certain thickness. Therefore, the conventional membrane keyboard still has room for improvement. Summary of the invention

[0004] In view of the above problems, the main purpose of the present invention is to provide a key structure, which solves the weight and thickness problems of the conventional membrane keyboard by using a novel design of a circuit board including a hook.

[0005] To achieve the above-mentioned purpose, the present invention provides a key structure, which includes a keycap, a connecting component and a circuit board. One end of the connecting component is connected to the keycap. The circuit board includes an upper film, a middle substrate, a lower film and a hook. The middle substrate includes a first insulating surface and a second insulating surface opposite to each other. The first insulating surface is connected to the upper film. The lower film is connected to the second insulating surface of the middle substrate. The hook is at least connected to the middle substrate. The hook passes through the upper film and extends toward the keycap, and the other end of the connecting component is connected to the hook.

[0006] According to an embodiment of the present invention, the hook further connects the upper film and the lower film.

[0007] According to an embodiment of the present invention, the upper film includes a first opening, the middle substrate includes a second opening, and the lower film includes a third opening. The first opening, the second opening, and the third opening together form a through hole. A bottom of the hook is disposed in the through hole.

[0008] According to an embodiment of the present invention, the diameters of the first opening and the third opening are larger than the diameter of the second opening.

[0009] According to an embodiment of the present invention, the hook is manufactured by insert injection molding, and the bottom of the hook is formed in the through hole.

[0010] According to an embodiment of the present invention, the middle substrate and the hook are formed together by stamping. In addition, one end of the hook is connected to the middle substrate, and the other end faces the key cap.

[0011] According to an embodiment of the present invention, the upper film includes a first opening, and the hook passes through the first opening toward the connecting component and the key cap.

[0012] According to an embodiment of the present invention, the lower film is a closed plate.

[0013] According to an embodiment of the present invention, the middle substrate is a metal plate, and two opposite surfaces of the metal plate are coated with an insulating paint to form a first insulating surface and a second insulating surface.

[0014] According to an embodiment of the present invention, the upper film and the lower film are respectively a plastic plate.

[0015] According to an embodiment of the present invention, the middle substrate includes a hollow portion. The upper film includes an upper conductive circuit, which is disposed on a surface of the upper film facing the middle substrate. The lower film includes a lower conductive circuit, which is disposed on a surface of the lower film facing the middle substrate. The upper conductive circuit and the lower conductive circuit correspond to the hollow portion.

[0016] As mentioned above, according to the key structure of the present invention, its circuit board includes an upper film, a middle substrate, a lower film and a hook. The middle substrate includes a first insulating surface and a second insulating surface relative to each other. In addition, the hook is at least connected to the middle substrate. The hook passes through the upper film and extends in the direction of the keycap, so that the connecting component can be connected to the hook. When the keycap is pressed, the main supporting force can be provided by the middle substrate, and there is no need to set up a base plate separately. In other words, in addition to the function of the circuit board itself, the circuit board of the present invention can also directly replace the base plate of the conventional keyboard. Therefore, a keyboard using the key structure of the present invention can reduce its overall weight and thickness to meet the design concept of lightness and thinness. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is an exploded schematic diagram of the key structure of the first embodiment of the present invention;

[0018] Figure 2 for Figure 1 The schematic diagram of the circuit board after assembly shown;

[0019] Figure 3 for Figure 1 The schematic diagram of the key structure after combination shown;

[0020] Figure 4 for Figure 3 An enlarged schematic diagram of a circled portion A of the key structure shown;

[0021] Figure 5 for Figure 3 An enlarged schematic diagram of the circled portion B of the key structure shown;

[0022] Figure 6 is an exploded schematic diagram of a key structure according to a second embodiment of the present invention;

[0023] Figure 7 for Figure 6 The schematic diagram of the circuit board after assembly shown;

[0024] Figure 8 for Figure 6 The schematic diagram of the key structure after combination shown;

[0025] Fig. 9 for Figure 8 An enlarged schematic diagram of the circled portion C of the key structure shown.

[0026]

Explanation of symbols

[0027] Key structure 1, 1a

[0028] Circuit boards 10, 10a

[0029] Upper film 11, 11a

[0030] First openings 111, 111a

[0031] Upper conduction circuit 112

[0032] Middle layer substrates 12, 12a

[0033] Second openings 121, 121a

[0034] Hollow parts 122, 122a

[0035] First insulating surface 123, 123a

[0036] Second insulating surfaces 124, 124a

[0037] Lower film 13, 13a

[0038] The third opening 131

[0039] Lower conduction circuit 132

[0040] Light-shielding ink 133

[0041] Hooks 14, 14a

[0042] Bottom 141

[0043] Hook 142

[0044] Connecting components 20

[0045] Outer frame 21

[0046] Inner frame 22

[0047] Keycap 30

[0048] Elastic member 40

[0049] Circle A, B, C

[0050] Through hole H DETAILED DESCRIPTION

[0051] In order to better understand the technical content of the present invention, preferred specific embodiments are described below.

[0052] Figure 1 is an exploded schematic diagram of the key structure of the first embodiment of the present invention, Figure 2 for Figure 1 The schematic diagram of the circuit board after assembly is shown. Figure 3 for Figure 1 Please refer to the schematic diagram of the key structure combination shown in the figure. Figure 1 , Figure 2 and Figure 3 As shown. In this embodiment, the key structure 1 includes a circuit board 10, a connecting component 20 and a key cap 30. Among them, the key structure 1 can be applied to a membrane keyboard, so the circuit board 10 is a membrane circuit board with a three-layer structure (or a membrane switch circuit board). In this embodiment, the circuit board 10 includes an upper film 11, a middle substrate 12, a lower film 13 and a hook 14. Figure 1 For example, the three-layer structure of the circuit board 10 is, from top to bottom, an upper film 11, a middle substrate 12, and a lower film 13. Among them, the upper film 11 is closest to the keycap 30. The hook 14 is at least connected to the middle substrate 12. In this embodiment, the hook 14 is connected to the upper film 11, the middle substrate 12, and the lower film 13 at the same time. Moreover, the hook 14 passes through the upper film 11 and extends toward the keycap 30.

[0053] Preferably, the middle substrate 12 of this embodiment can be a metal plate, such as an iron plate, so as to increase the structural strength of the circuit board 10. Preferably, the hook 14 can be made by embedding injection molding. Figure 1As shown, the upper film 11 includes a first opening 111, the middle substrate 12 includes a second opening 121, and the lower film 13 includes a third opening 131. The number of the first opening 111, the second opening 121, and the third opening 131 corresponds to the number of the hooks 14, and four are used as an example in this embodiment. When preparing the circuit board 10, the upper film 11, the middle substrate 12, and the lower film 13 can be stacked first, and the first opening 111, the second opening 121, and the third opening 131 are aligned with each other, so that the first opening 111, the second opening 121, and the third opening 131 together form a through hole H (marked at Figure 2 The upper film 11, the middle substrate 12 and the lower film 13 may be bonded to each other by water glue.

[0054] Next, the stacked and bonded upper film 11, middle substrate 12 and lower film 13 are placed in a mold, and the hook 14 is formed at the through hole H by insert injection. The bottom 141 of the hook 14 is formed in the through hole H, and a hook portion 142 is formed from the upper film 11 toward the keycap 30. In other words, the hook 14 of this embodiment includes the bottom 141 and the hook portion 142. The bottom 141 is disposed in the through hole H, and the hook portion 142 extends from the upper film 11 toward the keycap 30.

[0055] Figure 4 for Figure 3 Please refer to the enlarged schematic diagram of the circled area A of the key structure shown in FIG. Figure 1 and Figure 4 As shown. Preferably, the apertures of the first opening 111 and the third opening 131 are larger than the aperture of the second opening 121. In other words, the apertures of the openings located in the upper film 11 and the lower film 13 (i.e., the first opening 111 and the third opening 131) are larger than the apertures of the openings located in the middle substrate 12 (i.e., the second opening 121). Therefore, when the upper film 11, the middle substrate 12, and the lower film 13 are stacked, a structure in which the middle substrate 12 protrudes toward the through hole H can be formed in the through hole H (indicated by the edge line of the inner wall of the through hole H). When the hook 14 is formed by embedded injection, the protruding structure of the middle substrate 12 allows the bottom 141 to be stably set in the through hole H.

[0056] In addition, the hook 14 passes through the upper film 11 and extends toward the keycap 30, so that the hook 14 can be used to connect the connecting component 20. In this embodiment, one end of the connecting component 20 is connected to the keycap 30, and the other end is connected to the hook 14 of the circuit board 10. It should be noted that the connecting component 20 of this embodiment is a scissor-type connecting component, so the connecting component 20 includes an outer frame 21 and an inner frame 22 pivotally connected to each other. One end of the outer frame 21 is connected to the keycap 30, and the other end is connected to the hook 14 of the circuit board 10. Similarly, one end of the inner frame 22 is connected to the keycap 30, and the other end is connected to the hook 14 of the circuit board 10. Therefore, one end of the connecting component 20 referred to in this embodiment can be one end of the outer frame 21 and one end of the inner frame 22. The other end of the connecting component 20 referred to in this embodiment can be the other end of the outer frame 21 and the other end of the inner frame 22. Through the above structure, the (scissor-type) connecting component 20 can guide the keycap 30 to rise and fall relative to the circuit board 10. When the keycap 30 is pressed, the middle substrate 12 (metal plate) with relatively high strength can provide the main supporting force.

[0057] It should be noted that the shape of the circuit board 10 may correspond to a membrane keyboard, such as a rectangle, and the attached drawings of the present case only show a portion of the structure of the circuit board 10 corresponding to one of the key structures 1. In addition, the number of hooks 14 (i.e., four) shown in the attached drawings of the present case also corresponds to the number of one of the key structures 1 (or keycaps 30), which can be adjusted according to the structure of the connecting component 20. Specifically, the connecting component 20 of the present embodiment includes an outer frame 21 and an inner frame 22. Furthermore, the opposite sides of the outer frame 21 and the inner frame 22 are connected to the circuit board 10, so the circuit board 10 corresponding to each key structure 1 may have four hooks 14, such as Figure 1 and Figure 2 shown.

[0058] Figure 5 for Figure 3 Please refer to the enlarged schematic diagram of the circled portion B of the key structure shown in FIG. Figure 3 and Figure 5 As shown. In this embodiment, the middle substrate 12 includes a hollow portion 122, a first insulating surface 123 and a second insulating surface 124 opposite to each other. The first insulating surface 123 faces and is connected to the upper film 11, and the second insulating surface 124 faces and is connected to the lower film 13. In addition, the corresponding surfaces of the upper film 11 and the lower film 13 respectively have conductive circuits (for example, circuits configured with silver paste lines), which are at least partially located in the hollow portion 122. The first insulating surface 123 and the second insulating surface 124 are used to prevent the conductive circuits outside the hollow portion 122 from contacting each other.

[0059] Specifically, if Figure 5As shown, the upper film 11 includes an upper conductive circuit 112, which is disposed on a surface of the upper film 11 facing the middle substrate 12. The lower film 13 includes a lower conductive circuit 132, which is disposed on a surface of the lower film 13 facing the middle substrate 12. The upper conductive circuit 112 and the lower conductive circuit 132 correspond to the hollow portion 122. In other words, the upper conductive circuit 112 is disposed on the lower surface of the upper film 11, and is partially located in the hollow portion 122. The lower conductive circuit 132 is disposed on the upper surface of the lower film 13, and is partially located in the hollow portion 122.

[0060] refer to Figure 1 , Figure 3 and Figure 5 As shown, the key structure 1 of this embodiment further includes an elastic member 40. The elastic member 40 is disposed between the circuit board 10 and the key cap 30 and is located in the connecting assembly 20. When the key cap 30 is pressed, the elastic member 40 presses down the upper film 11, causing the upper film 11 to deform toward the hollow portion 122, thereby causing the upper conductive circuit 112 to contact with the lower conductive circuit 132 of the lower film 13 and conduct, thereby generating a trigger signal.

[0061] In order to prevent the upper conductive circuit 112 and the lower conductive circuit 132 located outside the hollow portion 122 from being connected to each other, the upper and lower surfaces of the middle substrate 12 must be made of insulating materials (i.e., the first insulating surface 123 and the second insulating surface 124). Since the middle substrate 12 of this embodiment is a metal plate, preferably, insulating paint can be applied to the two opposite surfaces of the metal plate, for example, by roller coating, to form the first insulating surface 123 and the second insulating surface 124.

[0062] In the present embodiment, the main supporting force is provided by the middle substrate 12 made of metal material, so the circuit board 10 of the present embodiment can replace the bottom plate of the conventional keyboard. Preferably, the upper film 11 and the lower film 13 can use a lighter material. The upper film 11 and the lower film 13 of the present embodiment are respectively plastic films, which can be, for example but not limited to, polyethylene terephthalate (PET or PETE for short). In other embodiments, the upper film 11, the middle substrate 12 and the lower film 13 can all be made of plastic materials. By increasing the thickness of the middle substrate 12 to increase its strength, and forming the hook 14 by injection molding, the circuit board 10 can also replace the bottom plate of the conventional keyboard. In addition, in the embodiment where the middle substrate 12 is a plastic plate body, its two opposite surfaces are the first insulating surface 123 and the second insulating surface 124, and there is no need to apply insulating paint separately.

[0063] Preferably, the lower film 13 is made of a light-transmissive material and includes a light-shielding ink 133, such as Figure 5As shown. The light-shielding ink 133 is disposed on a surface of the lower film 13 away from the middle substrate 12. When a backlight module (not shown) is disposed below the key structure 1, the light-shielding ink 133 can be used to block light, and a light-transmitting area is formed where the light-shielding ink 133 is not disposed, so that light can irradiate the key structure 1 through the light-transmitting area. In this embodiment, the light-shielding ink 133 is disposed on the lower surface of the lower film 13, but the present invention is not limited thereto. In other embodiments, the light-shielding ink 133 can also be disposed on the upper surface of the lower film 13. Specifically, the lower film 13 is made of plastic material, so the light-shielding ink 133 can be formed on the lower surface or upper surface of the lower film 13 by roller coating, spraying, etc., so that the lower film 13 can also be used as a light-shielding sheet.

[0064] Figure 6 is an exploded schematic diagram of the key structure of the second embodiment of the present invention, Figure 7 for Figure 6 The schematic diagram of the circuit board after assembly is shown. Figure 8 for Figure 6 The schematic diagram of the key structure after combination is shown. Fig. 9 for Figure 8 Please refer to the enlarged schematic diagram of the circled portion C of the key structure shown in FIG. Figure 6 , Figure 7 , Figure 8 and Fig. 9 As shown. The key structure 1a of this embodiment also includes a circuit board 10a, a connecting component 20, a key cap 30 and an elastic member 40. Among them, the structure and connection relationship of the connecting component 20, the key cap 30 and the elastic member 40 are the same as those of the first embodiment, so their numbers are used. In this embodiment, the circuit board 10a also includes an upper film 11a, a middle substrate 12a, a lower film 13a and a hook 14a. The main difference from the previous embodiment is that the hook 14a of this embodiment is only connected to the middle substrate 12a, but not to the upper film 11a and the lower film 13a.

[0065] In this embodiment, the middle substrate 12a and the hook 14a can be formed together by stamping and bending. One end of the hook 14a is connected to the middle substrate 12a, and the other end faces the keycap 30. Specifically, the middle substrate 12a can be a metal plate or a plastic plate. The middle substrate 12a of this embodiment is a plastic plate as an example. When preparing the middle substrate 12a and the hook 14a, the complete plastic plate (or metal plate) can be stamped to form holes such as the second opening 121a and the hollow portion 122a, and at the same time, a planar hook 14a structure is formed. Then, the planar hook 14a is bent upward to form a hook 14a protruding in the direction of the keycap 30.

[0066] In this embodiment, since the middle substrate 12a is a plastic plate, its two opposite surfaces are respectively a first insulating surface 123a and a second insulating surface 124a. Figure 6 As shown. Preferably, the thickness of the middle substrate 12a is greater than the thickness of the upper film 11a and the lower film 13a to provide better strength and support. In addition, the upper film 11a also includes an upper conduction circuit, and the lower film 13a also includes a lower conduction circuit to generate a trigger signal. The details of generating the trigger signal can be directly referred to the description of the first embodiment, and will not be repeated here.

[0067] In this embodiment, since the hook 14a is only connected to the middle substrate 12a, the lower film 13a can be a closed film. Therefore, the lower film 13a of this embodiment is more suitable for being used as a light shielding film. The relevant contents of the light shielding ink can be directly referred to the description of the first embodiment above, and no further description is given here.

[0068] In addition, the upper film 11a of the present embodiment also includes a first opening 111a. The hook 14a located on the middle substrate 12a can pass through the first opening 111a and then extend toward the connecting component 20 and the keycap 30. Compared with the first embodiment, the first opening 111a and the second opening 121a of the present embodiment are larger in area, which can reduce the overall weight of the circuit board 10a and can serve as a space for the pivot connecting the connecting component 20 and the hook 14 to move downward, so as to ensure that the elastic member 40 can press down the upper film 11a to generate a trigger signal.

[0069] In summary, according to the key structure of the present invention, its circuit board includes an upper film, a middle substrate, a lower film and a hook. The middle substrate includes a first insulating surface and a second insulating surface relative to each other. Furthermore, the hook is at least connected to the middle substrate. The hook passes through the upper film and extends in the direction of the keycap, so that the connecting component can be connected to the hook. When the keycap is pressed, the main supporting force can be provided by the middle substrate, and there is no need to set up a base plate separately. In other words, in addition to the function of the circuit board itself, the circuit board of the present invention can also directly replace the base plate of the conventional keyboard. Therefore, a keyboard using the key structure of the present invention can reduce its overall weight and thickness to meet the design concept of lightness and thinness.

[0070] It should be noted that the above embodiments are provided for the purpose of illustration, and the scope of rights claimed by the present invention should be based on the claims, rather than being limited to the above embodiments.

Claims

1. A key structure, characterized in that: include: One key cap; a connecting component, one end of which is connected to the key cap; as well as A circuit board, comprising: an upper film; A middle substrate, comprising a first insulating surface and a second insulating surface opposite to each other, wherein the first insulating surface is connected to the upper film; a lower film connected to the second insulating surface of the middle substrate; and A hook is at least connected to the middle substrate, the hook passes through the upper film and extends toward the key cap, and the other end of the connecting component is connected to the hook.

2. The key structure according to claim 1, characterized in that: The hook further connects the upper film and the lower film.

3. The key structure according to claim 2, characterized in that: The upper film includes a first opening, the middle substrate includes a second opening, the lower film includes a third opening, the first opening, the second opening and the third opening together form a through hole, and a bottom of the hook is arranged in the through hole.

4. The key structure according to claim 3, characterized in that: The apertures of the first opening and the third opening are larger than the aperture of the second opening.

5. The key structure according to claim 3, characterized in that: The hook is made by embedding injection, and the bottom of the hook is formed in the through hole.

6. The key structure according to claim 1, characterized in that: The middle substrate and the hook are formed together by stamping, and one end of the hook is connected to the middle substrate, and the other end faces the key cap.

7. The key structure according to claim 6, characterized in that: The upper film comprises a first opening, and the hook passes through the first opening and faces the connecting component and the key cap.

8. The key structure according to claim 6, characterized in that: The lower film is a closed plate.

9. The key structure according to claim 1, characterized in that: The middle substrate is a metal plate, and an insulating paint is used to coat two opposite surfaces of the metal plate to form the first insulating surface and the second insulating surface.

10. The key structure according to claim 1, characterized in that: The lower film includes a light-shielding ink, which is arranged on a surface of the lower film away from the middle substrate.

11. The key structure according to claim 1, characterized in that: The middle substrate includes a hollow portion, the upper film includes an upper conductive circuit, which is arranged on a surface of the upper film facing the middle substrate, and the lower film includes a lower conductive circuit, which is arranged on a surface of the lower film facing the middle substrate. The upper conductive circuit and the lower conductive circuit correspond to the hollow portion.

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