CN109509667B

CN109509667B - Key structure

Info

Publication number: CN109509667B
Application number: CN201710833375.XA
Authority: CN
Inventors: 蔡磊龙
Original assignee: Primax Electronics Ltd
Current assignee: Primax Electronics Ltd
Priority date: 2017-09-15
Filing date: 2017-09-15
Publication date: 2020-07-10
Anticipated expiration: 2037-09-15
Also published as: CN109509667A

Abstract

The invention discloses a key structure, which comprises a flexible key cap, a conductive disc, a switch circuit board capable of generating a key signal and an elastic element. The transmission disc is fixed on the inner surface of the soft key cap and is contacted with a plurality of inner side walls of the soft key cap. The switch circuit board is arranged below the transmission disc, and the elastic element is arranged between the transmission disc and the switch circuit board. When the soft key cap receives the touch pressure, the conductive disc is twisted corresponding to the deformed soft key cap and pushes against a plurality of inner side walls of the soft key cap so as to conduct the touch pressure to corners of the soft key cap.

Description

Key structure

Technical Field

The present invention relates to a key structure, and more particularly to a light and thin key structure.

Background

Common peripheral input devices for computers include mice, keyboards, trackballs, etc., wherein the keyboard can directly input characters and symbols to the computer, and therefore, the users and manufacturers of the input devices pay attention to the input devices. Among them, a keyboard including a scissors-type connecting element is more common.

The structure of the key structure in the keyboard including the scissors-type connecting element is described next. Please refer to fig. 1, which is a schematic cross-sectional side view of a conventional key structure. The conventional key structure 1 includes a key cap 11, a scissors-type connecting element 12, an elastic rubber body 13, a membrane switch circuit 14 and a bottom plate 15, and the bottom plate 15 is used for carrying the key cap 11, the scissors-type connecting element 12, the elastic rubber body 13 and the membrane switch circuit 14. Wherein the scissors-type connecting element 12 is used to connect the bottom plate 15 and the key cap 11.

The scissors connecting element 12 is located between the bottom plate 15 and the key cap 11 and connects the two. Scissor linkage 12 includes a first frame 121 and a second frame 122. A first end of the first frame 121 is connected to the keycap 11, and a second end of the first frame 121 is connected to the bottom plate 15. The elastic rubber 13 is surrounded by the scissors-type connecting element 12, and the membrane switch circuit 14 has a plurality of key contacts (not shown). The key contact outputs a corresponding key signal when triggered. The elastic rubber body 13 is arranged on the membrane switch circuit 14, one elastic rubber body 13 corresponds to one key contact, and when the elastic rubber body 13 is pressed, the elastic rubber body 13 deforms and presses the corresponding key contact in the membrane switch circuit 14 to generate a key signal.

The operation of the conventional key structure 1 pressed by the user will be described next. In fig. 1, when the user presses the key cap 11, the key cap 11 is forced to push the scissors-type connecting element 12 to move, so that the key cap 11 can move downward relative to the bottom plate 15 and press the corresponding elastic rubber 13. At this time, the elastic rubber 13 deforms and presses the membrane switch circuit 14 to trigger the key contact of the membrane switch circuit 14, so that the membrane switch circuit 14 outputs a corresponding key signal. When the user stops pressing the key cap 11, the key cap 11 is no longer stressed and stops pressing the elastic rubber 13, so that the elastic rubber 13 is restored to its original shape due to its elasticity, and at the same time, provides an upward elastic restoring force, so that the key cap 11 is pushed back to the position before being pressed. The above is the structure and operation of the existing key structure.

With the development of technology, users increasingly demand lighter and thinner keyboards, and keyboard manufacturers are dedicated to develop thinner key structures, however, the key structures developed by the manufacturers are still limited by the structure of the connecting elements such as scissors-type connecting elements connecting the key caps and the bottom plate, and the reduction of the thickness is limited. Therefore, a key structure using a soft key cap is provided in the market, wherein the soft key cap is made of an elastic rubber material. The key structure is not provided with a scissors type connecting element, so that the thickness of the key structure can be reduced.

However, the absence of the scissor-type connecting element poses new problems: the soft key cap is easy to be stressed unevenly. For example, when a user touches and presses a corner of the soft key cap, the soft key cap is made of a soft elastic rubber material, and the supporting force of the soft key cap is insufficient due to the absence of the scissors-type connecting element, so that the touch pressure applied to the soft key cap by the user cannot be transmitted to the whole soft key cap from the corner. In other words, when the user touches the soft key cap, the soft key cap is stressed unevenly, so that the key signal cannot be generated, and the malfunction is caused.

Therefore, a key structure with a light and thin profile and capable of avoiding malfunction is needed.

Disclosure of Invention

The invention aims to provide a key structure which has a light and thin appearance and avoids misoperation.

In a preferred embodiment, the present invention provides a key structure, which includes a flexible key cap, a conductive plate, a switch circuit board and an elastic element, wherein the flexible key cap is exposed outside the key structure for being pressed to deform. The conducting disc is fixed on an inner surface of the soft key cap and is in contact with a plurality of inner side walls of the soft key cap. The switch circuit board is arranged below the conducting disc and is used for being triggered in response to the deformation of the soft key cap so as to generate a key signal. The elastic element is arranged between the conduction disc and the switch circuit board and is used for being pushed by the conduction disc to touch and press the switch circuit board; when the soft key cap is pressed and receives a touch pressure, the conduction disc is twisted according to the deformed soft key cap and pushes against the inner side walls of the soft key cap so as to conduct the touch pressure to one corner of the soft key cap.

In a preferred embodiment, the soft key cap includes a plurality of oblique corner posts and a fixing post. Each oblique angle column corresponds to the inner side wall of the key cap and extends out of the inner side wall of the corresponding key cap, and the oblique angle column is arranged on the inner side wall of the corresponding key cap and is close to the corner of the soft key cap. The fixing column is arranged on an inner surface of the key cap and extends out of the inner surface of the key cap. The oblique angle column is provided with an asymmetric inclined surface facing the inner surface of the key cap and used for being contacted with the conduction plate and being pushed by the twisted conduction plate to conduct the contact pressure to the corner of the soft key cap.

In a preferred embodiment, the conductive plate includes a body and a plurality of protruding bumps, the body has an opening, the fixing post passes through the opening, and the body is fixed on the inner surface of the soft key cap. The protruding lugs extend out of the body, each protruding lug corresponds to one oblique angle column, and each protruding lug is provided with a contact inclined plane corresponding to one asymmetric inclined plane and used for being in contact with the corresponding asymmetric inclined plane.

In short, the key structure of the present invention utilizes the structure of the soft key cap and the conductive plate to improve the problem of uneven stress of the soft key cap, and each inner sidewall of the soft key cap is provided with an oblique angle column, and the oblique angle column is close to a corner of the soft key cap. The conductive plate has protruding bumps protruding out of the body to contact the angled posts, respectively. The oblique angle column is provided with an asymmetric inclined surface facing upwards, and the protruding lug is provided with a contact inclined surface facing downwards. When the soft key cap is deformed due to the contact pressure, the contact pressure can be conducted to the corners of the soft key cap through the body, the protruding blocks and the oblique corner columns, so that the problem of uneven stress of the soft key cap can be solved, and the occurrence of false operation due to the contact pressure is avoided.

Drawings

Fig. 1 is a schematic cross-sectional side view of a conventional key structure.

FIG. 2 is an exploded view of the key structure of the present invention in a preferred embodiment.

Fig. 3 is a schematic structural diagram of a flexible key cap and a conductive plate of the key structure according to a preferred embodiment of the invention.

Fig. 4 is a partial sectional view of the flexible key cap and the conductive plate of the key structure according to a preferred embodiment of the invention.

FIG. 5 is a schematic cross-sectional side view of a key structure according to a preferred embodiment of the invention.

[ notation ] to show

1. 2 key structure 11 key cap

12-scissors type connecting element 13 elastic rubber body

14 film switch circuit 15 backplane

21 soft key cap 22 conductive disc

23 switch circuit board 24 elastic element

121 first frame 122 second frame

211 oblique angle column 212 fixing column

Inner surface of 213 Soft Key Cap inner side wall of 214 Soft Key Cap

215 corner 221 body of soft key cap

222 protruding out of the circuit board on the bump 231

232 lower wiring board 233 spacer layer

2112 asymmetric inclined 2121 cylinder

2122 opening of the stopper 2211

2221 contact inclined surface 2311 upper contact

2321 the bottom contact 2331 is opened by the spacer layer

Detailed Description

In view of the problems in the prior art, the present invention provides a key structure with a light and thin profile, which can avoid touch malfunction, so as to solve the problems in the prior art. Referring to fig. 2 and fig. 3, fig. 2 is an exploded view of a key structure of the present invention in a preferred embodiment, and fig. 3 is a schematic view of a flexible key cap and a conductive plate of the key structure of the present invention in a preferred embodiment. The key structure 2 includes a flexible key cap 21, a conductive plate 22, a switch circuit board 23 and an elastic element 24. The soft key cap 21 is exposed outside the key structure 2, and can be deformed by being pressed, and the soft key cap 21 includes a plurality of oblique corner posts 211 and fixing posts 212. The conductive plate 22 is fixed to the inner surface 213 of the soft key cap 21 and contacts with the inner sidewalls 214 of the soft key cap 21. The switch circuit board 23 is disposed below the conductive plate 22 and functions to be triggered in response to the deformation of the soft key cap 21 to generate a key signal. The elastic element 24 is disposed between the conductive plate 22 and the switch circuit board 23, and can be pushed by the conductive plate 22 to press the switch circuit board 23. In the preferred embodiment, the elastic element 24 is an elastic rubber body and is made of an elastic rubber material.

When the soft key cap 21 is pressed to receive the contact pressure, the soft key cap 21 deforms and partially recesses, and the inner surface 213 of the deformed soft key cap 21 pushes against the transmission plate 22, so that the transmission plate 22 twists and pushes against the inner side walls 214 of the soft key cap 21 to transmit the contact pressure to the corners of the soft key cap 21. Therefore, the key structure 2 of the present invention can solve the problem of uneven stress of the soft key cap 21.

The switch circuit board 23 includes an upper wiring board 231, a lower wiring board 232, and a separation layer 233. The upper wiring board 231 is in contact with the elastic element 24, and it has an upper contact 2311. The lower wiring board 232 is located below the upper wiring board 231, and has a lower contact 2321 corresponding to the upper contact 2311. The separation layer 233 is located between the upper wiring board 231 and the lower wiring board 232, and functions to isolate the upper wiring board 231 from the lower wiring board 232, so as to prevent the upper contacts 2311 from being erroneously contacted with the corresponding lower contacts 2321. And the spacer layer 233 has spacer layer openings 2331 corresponding to the upper contacts 2311. When the elastic element 24 contacts and presses the upper wiring board 231, the upper contact 2311 extends into the separating layer opening 2331 to contact with the lower contact 2321, so that the switch circuit board 23 generates a key signal. In the preferred embodiment, the switch circuit board 23 is a thin film switch circuit.

Referring to fig. 2, fig. 3 and fig. 4, fig. 4 is a schematic partial sectional view of a soft key cap and a conductive plate of a key structure according to a preferred embodiment of the invention. In the soft key cap 21, each of the plurality of oblique corner posts 211 corresponds to an inner sidewall 214 of one key cap 21 and extends out of the corresponding inner sidewall 214 of the key cap 21, and the oblique corner posts 211 are disposed on the corresponding inner sidewall 214 of the key cap 21 and are close to corners 215 of the soft key cap 21. The fixing posts 212 are disposed on the inner surface 213 of the key cap 21 and extend out of the inner surface 213 of the key cap 213. Each of the oblique corner posts 211 has an asymmetric oblique surface 2112 facing the inner surface 213 of the key cap 21, i.e., facing upward, the asymmetric oblique surface 2112 can contact the conductive plate 22 and can be pushed by the twisted conductive plate 22 to transmit the received contact pressure to the corner 215 of the soft key cap 21. In the preferred embodiment, the oblique corner posts 211 and the fixing posts 212 are integrally formed with the soft key cap 21, and the soft key cap 21 is made of an elastic rubber material.

In fig. 2, 3 and 4, the conductive plate 22 includes a main body 221 and a plurality of protruding bumps 222, the main body 221 has an opening 2211, so that the fixing posts 212 of the soft key cap 21 pass through the opening 2211, and the main body 221 is fixed on the inner surface 213 of the soft key cap 21. A plurality of protruding protrusions 222 protrude from the body 221, each protruding protrusion 222 corresponds to one of the corner posts 211, each protruding protrusion 222 has a contact inclined surface 2221, and the contact inclined surface 2221 corresponds to an asymmetric inclined surface 2112, which can contact with the corresponding asymmetric inclined surface 2112, as shown in fig. 4. In the preferred embodiment, the protruding bumps 222 are integrally formed with the body 221, and the body 221 is made of an elastic rubber material.

On the other hand, the fixing post 212 of the soft key cap 21 includes a post 2121 and a stopper 2122, and the post 2121 can pass through the opening 2211 of the main body 221. The limiting portion 2122 is disposed at one end of the pillar 2121, and contacts the main body 221 when the main body 221 is sleeved on the pillar 2121, so as to fix the main body 221 on the inner surface 213 of the soft key cap 21. It should be noted that although the size of the position-limiting portion 2122 is larger than the opening 2211, since the body 221 is made of elastic rubber material, it can slightly deform to enlarge the opening 2211, so that the position-limiting portion 2122 can pass through the opening 2211 to fit the body 221 on the cylinder 2121.

Referring to fig. 2, fig. 3, fig. 4 and fig. 5, fig. 5 is a schematic cross-sectional side view of a key structure according to a preferred embodiment of the invention. Fig. 5 shows the key structure 2 formed by combining the components, and the operation of the key structure 2 of the present invention is touched and pressed by the user's force as follows: when a user's finger touches any corner 215 of the soft key cap 21, the soft key cap 21 deforms and the inner surface 213 thereof pushes against the main body 221 of the transmission disc 22, and the pushed main body 221 twists in response to the structure of the contact inclined surfaces 2221 and the corresponding asymmetric inclined surfaces 2112, so that the contact inclined surfaces 2221 push against the asymmetric inclined surfaces 2112 to transmit the touch pressure to other corners 215 of the soft key cap 21. It should be noted that the twisting direction of the conductive plate 22 is determined by the arrangement direction of the asymmetric inclined surface 2112 and the arrangement direction of the corresponding contact inclined surface 2221.

On the other hand, the twisted body 221 pushes down the elastic element 24, so that the elastic element 24 deformed by the elastic element 24 touches the switch circuit board 23 to trigger the switch circuit board 23 to generate the key signal. When the user stops pressing the soft key cap 21, the elastic element 24 is restored from the deformed state and provides an upward pushing force to the main body 221, so that the conductive plate 22 is pushed back to the position before being pressed. The soft key cap 21 is also restored from the deformed state.

According to the above, the key structure of the present invention utilizes the structure of the soft key cap and the conductive plate to improve the problem of uneven stress of the soft key cap, and each inner sidewall of the soft key cap is provided with the oblique corner column, and the oblique corner column is close to the corner of the soft key cap. The conductive plate has protruding bumps protruding out of the body to contact the angled posts, respectively. The oblique angle column is provided with an asymmetric inclined surface facing upwards, and the protruding lug is provided with a contact inclined surface facing downwards. When the soft key cap is deformed due to the contact pressure, the contact pressure can be conducted to the corners of the soft key cap through the body, the protruding blocks and the oblique corner columns, so that the problem of uneven stress of the soft key cap can be solved, and the occurrence of false operation due to the contact pressure is avoided.

The above description is only a preferred embodiment of the present invention and should not be taken as limiting the claims, so that other equivalent changes and modifications without departing from the spirit of the present invention are intended to be included in the claims.

Claims

1. A key structure, comprising:

a soft key cap exposed outside the key structure for being deformed by being pressed;

a conducting disc fixed on an inner surface of the soft key cap and contacted with a plurality of inner side walls of the soft key cap;

a switch circuit board arranged below the conducting disc for being triggered to generate a key signal in response to the deformation of the soft key cap; and

the elastic element is arranged between the conduction disc and the switch circuit board and is used for being pushed by the conduction disc to touch and press the switch circuit board; when the soft key cap is pressed and receives a touch pressure, the conduction disc is twisted according to the deformed soft key cap and pushes against the inner side walls of the soft key cap so as to conduct the touch pressure to one corner of the soft key cap;

wherein, this soft button cap includes:

a plurality of oblique angle columns, each oblique angle column corresponding to the inner side wall of a key cap and extending out of the inner side wall of the corresponding key cap, the oblique angle columns being arranged on the inner side wall of the corresponding key cap and close to the corners of the soft key cap; and

and the fixing column is arranged on an inner surface of the key cap and extends out of the inner surface of the key cap.

2. The key structure of claim 1, wherein the oblique angle pillar has an asymmetric oblique surface facing the inner surface of the key cap for contacting the conductive plate and being pushed by the twisted conductive plate to transmit the contact pressure to the corner of the soft key cap.

3. The key structure of claim 1, wherein the plurality of corner posts and the fixing posts are integrally formed with the soft key cap, and the soft key cap is made of an elastic rubber material.

4. The key structure of claim 2, wherein the direction of the rotation of the conductive plate is determined by the direction of the asymmetric inclined surface.

5. The key structure of claim 2, wherein the conductive plate comprises:

a main body with an opening for the fixing column to pass through and fix the main body on the inner surface of the soft key cap; and

and the protruding lugs extend out of the body, each protruding lug corresponds to one oblique angle column, and each protruding lug is provided with a contact inclined plane corresponding to one asymmetric inclined plane and used for being in contact with the corresponding asymmetric inclined plane.

6. The key structure of claim 5, wherein the protruding bumps are integrally formed with the body, and the body is made of an elastic rubber material.

7. The key structure of claim 5, wherein the fixing post comprises:

a cylinder passing through the opening;

and the limiting part is arranged at one end of the column body and is used for contacting the body when the body is sleeved on the column body so as to fix the body on the inner surface of the soft key cap.

8. The key structure of claim 5, wherein when the soft key cap receives the touch pressure, the soft key cap deforms and pushes against the body, and the pushed body twists, so that the plurality of contact slopes push against the asymmetric slope to transmit the touch pressure to the corners of the soft key cap.

9. The key structure of claim 1, wherein the switch circuit board comprises:

an upper circuit board, which is contacted with the elastic element and is provided with an upper contact point;

a lower circuit board which is positioned below the upper circuit board and is provided with a lower contact point; and

a separation layer arranged between the upper circuit board and the lower circuit board for separating the upper circuit board and the lower circuit board, wherein the separation layer is provided with a separation layer opening; when the elastic element contacts and presses the upper circuit board, the upper contact point extends into the opening of the separation layer and contacts with the lower contact point, so that the switch circuit board generates the key signal.