Membrane keyboard with improved structure
By coating the inner wall of the keyboard casing with a waterproof adhesive layer and setting up a labyrinthine vent, as well as setting up vents and air channels inside the membrane circuit board, the waterproofing and venting problems of traditional membrane keyboards are solved, thus protecting the circuit board and extending its service life.
Patent Information
- Application Number
- CN202423232690.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-26
- Publication Date
- 2025-12-02
- Estimated Expiration
- 2034-12-26
AI Technical Summary
Traditional membrane keyboards lack waterproofing and venting capabilities, allowing liquids to enter the keyboard casing and damage the circuit board. Furthermore, the sealed structure can cause key contacts to become either difficult or easy to conduct when temperatures change.
A waterproof adhesive layer is applied to the inner wall of the keyboard casing, and a labyrinthine dustproof and venting hole is set at the edge of the casing. At the same time, vent holes and horizontal air channels are set in the thin film circuit board. Combined with an elastic buffer layer and an annular elastic protrusion structure, waterproof and venting functions are achieved.
It effectively prevents liquid from entering the keyboard, vents gas, avoids damage to the circuit board, and improves the keyboard's lifespan and reliability in harsh environments.
Smart Images
Figure CN223624868U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a notebook keyboard, and more particularly to a membrane keyboard with improved structure. Background Technology
[0002] Traditional laptop membrane keyboards generally lack waterproofing and venting capabilities. Water or other liquids entering the keyboard casing can soak the membrane circuit board, causing short circuits and damage. Therefore, to prevent water ingress, the membrane circuit board is designed with a sealed structure to provide waterproofing. However, over time, the adhesives and other components in the sealed membrane circuit board can generate gas. When the temperature rises, this gas expands, making it difficult for the key contacts on the membrane circuit board to conduct electricity; when the temperature drops, the gas contracts, making it easier for the key contacts to make contact and conduct electricity. Utility Model Content
[0003] To overcome the above shortcomings, this utility model provides a membrane keyboard with improved structure. This improved membrane keyboard has waterproof and venting functions and is not easily damaged during long-term use.
[0004] The technical solution adopted by this utility model to solve its technical problem is: an improved membrane keyboard, including a keyboard shell, a membrane circuit board, a key support plate, and keys. The membrane circuit board is fixedly installed inside the keyboard shell, and the key support plate is fixedly installed on the upper side of the membrane circuit board. The key support plate is provided with several key mounting holes that are directly opposite the membrane switches on the membrane circuit board. The keys are installed in the key mounting holes. Pressing down the key can trigger the membrane switches on the membrane circuit board. The inner sidewall surface of the keyboard shell is coated with a waterproof adhesive layer, which can seal and cover the edge gaps of the keyboard shell. The edge of the keyboard shell has a maze-shaped, reciprocating dustproof and venting hole. One end of the dustproof and venting hole passes through the edge of the keyboard shell and communicates with the outside, and the other end of the dustproof and venting hole communicates with the inside of the keyboard shell.
[0005] As a further improvement of this utility model, the dustproof vent extends in a zigzag pattern along the vertical direction, based on the actual usage direction of the keyboard.
[0006] As a further improvement of this utility model, the thin film circuit board includes an upper PET film, a middle partition layer, a lower PET layer, an adhesive layer, and a key base plate, which are sequentially bonded from top to bottom. A waterproof and breathable membrane is bonded to the lower side of the thin film circuit board through a waterproof adhesive layer. The middle partition layer, the lower PET layer, the adhesive layer, and the key base plate of the thin film circuit board are provided with vent holes that penetrate along their thickness direction. A horizontal air channel is formed between the middle partition layer and the upper PET film, and the horizontal air channel connects the vent holes to the inner space of the keyboard housing.
[0007] As a further improvement of this utility model, a backlight layer is also provided. The backlight layer is bonded to the underside of the button base plate or to the underside of the waterproof and breathable membrane by an adhesive layer. The backlight layer and the adhesive layer are also provided with breathable holes extending along their thickness.
[0008] As a further improvement of this utility model, an elastic buffer layer is also fixedly provided on the bottom inner side of the keyboard housing, and the thin film circuit board is fixedly attached to the surface of the elastic buffer layer.
[0009] As a further improvement of this utility model, the key support plate is provided with an annular elastic protrusion structure, which elastically abuts against the lower edge of the keycap.
[0010] The beneficial technical effects of this utility model are as follows: By coating the inner wall of the keyboard housing with a waterproof adhesive layer, the keyboard housing becomes waterproof, preventing external liquids from entering. Simultaneously, the keyboard housing features reciprocating dustproof vents to expel gases generated within the membrane circuit board, preventing external liquids and dust from entering through these vents. Furthermore, the utility model includes vent holes and horizontal air channels within the membrane circuit board to expel gases generated inside the keyboard housing, which are then discharged to the outside of the keyboard housing via the dustproof vents. Finally, the utility model incorporates a shock-absorbing structure within the keyboard housing to prevent damage to the membrane circuit board from vibration. This utility model provides ample protection for the membrane circuit board, preventing damage during use in harsh environments. Attached Figure Description
[0011] Figure 1 This is a front view illustrating the principle of the waterproof venting structure for the keyboard casing of this utility model.
[0012] Figure 2 for Figure 1 Cross-sectional view of the middle AA section;
[0013] Figure 3 This is a first interlayer structure diagram of the thin-film circuit board of this utility model;
[0014] Figure 4 This is a second interlayer structure diagram of the thin-film circuit board of this utility model; Detailed Implementation
[0015] Example: An improved membrane keyboard includes a keyboard housing 1, a membrane circuit board, a key support plate, and keys. The membrane circuit board is fixedly installed inside the keyboard housing 1, and the key support plate is fixedly disposed on the upper side of the membrane circuit board. The key support plate has several key mounting holes that are directly opposite the membrane switches on the membrane circuit board. The keys are installed in the key mounting holes. Pressing down on the key can trigger the membrane switches on the membrane circuit board. The inner wall surface of the keyboard housing 1 is coated with a waterproof adhesive layer 2, which can seal and cover the edge gaps of the keyboard housing 1. The edge of the keyboard housing 1 has a maze-shaped, reciprocating dustproof vent 3. One end of the dustproof vent 3 passes through the edge of the keyboard housing 1 and communicates with the outside, and the other end of the dustproof vent 3 communicates with the inside of the keyboard housing 1.
[0016] During use, external liquids cannot enter the keyboard casing through gaps, effectively reducing the possibility of the membrane circuit board being soaked or contaminated by liquids and preventing damage to the circuit board due to liquid. The membrane keyboard also features a maze-like dustproof vent 3 on the keyboard casing. Gases generated by the material itself during use can be discharged to the outside of the keyboard casing through the dustproof vent 3, preventing damage to the membrane circuit board due to heat expansion. At the same time, the maze-like dustproof vent 3 also prevents external liquids or dust from entering the keyboard casing 1 and contaminating the membrane circuit board, achieving full protection for the membrane circuit board, effectively extending the service life of the membrane keyboard, and enabling the membrane keyboard to be used in various harsh environments.
[0017] Based on the actual usage direction of the keyboard, the dustproof vent 3 extends in a zigzag pattern along the vertical direction, or it can extend in other directions.
[0018] The thin-film circuit board includes an upper PET film 4, a middle partition layer 5, a lower PET layer 6, an adhesive layer 7, and a key base plate 8, which are sequentially bonded from top to bottom. A waterproof and breathable membrane 9 is bonded to the lower side of the thin-film circuit board through a waterproof adhesive layer 15. The middle partition layer 5, the lower PET layer 6, the adhesive layer 7, and the key base plate 8 of the thin-film circuit board are provided with vent holes 10 that penetrate along their thickness direction. A horizontal air channel 11 is formed between the middle partition layer 5 and the upper PET film 4, and the horizontal air channel 11 connects the vent hole 10 to the inner space of the keyboard housing 1.
[0019] There are some gases inside the thin-film circuit board, such as the gases released by the adhesive layer during use. These gases can enter the vent 10 along the interlayer structure, and then be discharged into the keyboard housing 1 through the horizontal air passage 11 along the vent 10. Then, they are discharged to the outside of the keyboard housing through the dustproof exhaust hole 3, which avoids the thin-film circuit board from being unable to be discharged smoothly, causing poor signal or damage to the thin-film circuit board.
[0020] A backlight layer 12 is also provided, which is bonded to the underside of the key base plate 8 or to the underside of the waterproof and breathable membrane 9 via an adhesive layer 13. Ventilation holes 14 extending along the thickness of both the backlight layer 12 and the adhesive layer 13 are also provided. For membrane keyboards with luminous functionality, the backlight layer 12 below can also be provided with ventilation holes 14, allowing gas generated by the backlight layer 12 and adhesive layer 13 to escape through the ventilation holes 14, preventing internal air accumulation from affecting the uniformity of light emitted by the backlight layer 12.
[0021] An elastic buffer layer 16 is also fixedly provided on the inner bottom surface of the keyboard housing 1, and the thin film circuit board is fixedly attached to the surface of the elastic buffer layer 16. The elastic buffer layer 16 provides shock absorption for the thin film keyboard, preventing damage to the electronic components on the keyboard and causing malfunctions due to vibration.
[0022] The key support plate is provided with an annular elastic protrusion structure, which elastically abuts against the lower edge of the keycap. This annular elastic protrusion structure supports the edge of the keycap, providing shock absorption and improving key rebound.
Claims
1. An improved membrane keyboard, comprising a keyboard housing (1), a membrane circuit board, a key support plate, and keys, wherein the membrane circuit board is fixedly installed inside the keyboard housing, the key support plate is fixedly disposed on the upper side of the membrane circuit board, the key support plate is provided with a plurality of key mounting holes facing the membrane switches on the membrane circuit board, the keys are installed in the key mounting holes, and pressing the key can trigger the membrane switches on the membrane circuit board, characterized in that: The inner wall surface of the keyboard housing is coated with a waterproof adhesive layer (2), which can seal and cover the edge gaps of the keyboard housing. The edge of the keyboard housing is provided with a maze-shaped, reciprocating dustproof and exhaust hole (3). One end of the dustproof and exhaust hole passes through the edge of the keyboard housing and communicates with the outside, while the other end of the dustproof and exhaust hole communicates with the inside of the keyboard housing.
2. The improved membrane keyboard according to claim 1, characterized in that: Based on the actual usage direction of the keyboard, the dustproof vent extends in a zigzag pattern along the vertical direction.
3. The improved membrane keyboard according to claim 1, characterized in that: The thin-film circuit board includes an upper PET film (4), a middle partition layer (5), a lower PET layer (6), an adhesive layer (7), and a key base plate (8) that are sequentially bonded from top to bottom. A waterproof and breathable membrane (9) is bonded to the lower side of the thin-film circuit board through a waterproof adhesive layer (15). The middle partition layer, the lower PET layer, the adhesive layer, and the key base plate of the thin-film circuit board are provided with vent holes (10) that penetrate along their thickness direction. A horizontal air channel (11) is formed between the middle partition layer and the upper PET film. The horizontal air channel connects the vent hole to the inner space of the keyboard housing.
4. The improved membrane keyboard according to claim 3, characterized in that: It also has a backlight layer (12), which is bonded to the underside of the button base plate or to the underside of the waterproof and breathable membrane by an adhesive layer (13). The backlight layer and the adhesive layer also have breathable holes (14) extending along their thickness.
5. The improved membrane keyboard according to claim 1, characterized in that: an elastic buffer layer (16) is fixedly provided on the bottom inner side of the keyboard housing, and the membrane circuit board is fixedly attached to the surface of the elastic buffer layer.
6. The improved membrane keyboard according to claim 1, characterized in that: The key support plate is provided with an annular elastic protrusion structure, which elastically abuts against the lower edge of the keycap.