WO2020114075A1

WO2020114075A1 - Key structure and terminal

Info

Publication number: WO2020114075A1
Application number: PCT/CN2019/110423
Authority: WO
Inventors: 于杨惠文; 罗显友
Original assignee: 中兴通讯股份有限公司
Priority date: 2018-12-05
Filing date: 2019-10-10
Publication date: 2020-06-11
Also published as: CN111276352A; CN111276352B

Abstract

A key structure and a terminal, wherein the key structure comprises a casing (20), a key assembly (10) and a circuit board assembly (30); the casing (20) is provided with a key hole (221); the key assembly (10) comprises a key (11), a safety arm (14) and a mounting seat (13); the key (11) and the mounting seat (13) are connected through an elastic arm (12), and the mounting seat (13) and the casing (20) are connected; a limiting portion (112) is arranged on the side, close to the safety arm (14), of the key (11), a convex portion (15) extending outward is arranged on the side, far away from the limiting portion (112), of the safety arm (14); the circuit board assembly (30) is connected with the casing (20), and is arranged on the side, far away from the casing (20), of the key assembly (10).

Description

Button structure and terminal

This application claims the priority of the Chinese patent application CN201811480844.5 titled "A Key Structure and Terminal" filed on December 05, 2018, the entire contents of which are incorporated herein by reference.

Technical field

The invention relates to the technical field of mobile terminal keys, in particular to a key structure and terminal.

Background technique

Terminals such as communication electronic devices usually have physical function buttons for controlling power on/off, volume up/down, channel up/down, menu, confirmation and other functions. Plastic is currently the most commonly used material for the keys of such products. The self-elasticity of the plastic material can realize the pressing deformation and rebound of the cantilever structure of the button, eliminating the need for springs or other flexible parts and their complex structures, and through a specific design, a plastic part Can realize multiple key functions. At present, various types of plastic buttons have been widely used in communication electronic equipment. The assembly sequence commonly used in the industry is to first assemble the button and the device casing in a certain way, and then participate in the assembly of the whole machine together.

In some cases, the common design of plastic buttons is that a cross-top post is set on the back of the button as a trigger structure. The cross-top post is opposite to the switching device on the circuit board assembly, and there is a certain distance between the two. In consideration of the deformation of the elastic arm, the feel of the keys, and reliability, it is desirable that the distance between the cross-top post and the front end of the switching device on the circuit board be as small as possible, usually only designed to be 0.2 to 0.3 mm. As a result, during the assembly process of the whole machine, as long as there is a slight backward deformation of the button part, the cross top post will be scratched by the front contact of the switching device on the circuit board, resulting in an irreversible deformation of the corresponding button. When the device has multiple buttons in parallel, it is extremely difficult to avoid one or several buttons being scratched and deformed, which may cause assembly failure or even product quality problems.

Summary of the invention

The first object of the present invention is to provide a key structure to solve the problem that the key structure is easily deformed by scraping during the assembly process of the whole machine in some cases, thereby causing problems such as assembly failure and even product quality.

In order to achieve the above object, the technical solution proposed by the present invention is as follows: A key structure including: a housing provided with a key hole; a key component, the key component includes a key that cooperates with the key hole, respectively A safety arm and a mounting base connected to each other on opposite sides of the key; wherein the key is elastically connected to the mounting base, the mounting base is connected to the housing; when the key is close to the safety arm A limit part is provided on one side, and there is a preset distance between the limit part and the safety arm, and when the safety arm deforms toward the limit part, the two can resist each other. The side away from the limit portion is provided with an outwardly protruding convex portion; a circuit board assembly, the circuit board assembly is connected to the housing, and is located on the side of the key assembly away from the housing; When assembling, the circuit board assembly, the convex portion and the limiting portion are sequentially offset, so that a preset interval is formed between the key and the circuit board assembly.

A second object of the present invention is to provide a terminal having the key structure described in any one of the above technical solutions.

The advantages of the above additional aspects will be partially given in the following description, and some will become apparent from the following description, or be learned through the practice of the present invention.

BRIEF DESCRIPTION

FIG. 1 is a schematic exploded structural diagram of a button structure according to an embodiment of the present invention (1);

FIG. 2 is an exploded schematic structural view of a key structure according to an embodiment of the present invention (2);

3 is a schematic structural diagram of a button structure according to an embodiment of the present invention;

4 is a cross-sectional view of a key structure according to an embodiment of the invention.

In the drawings, the list of parts represented by each reference number is as follows:

10. Button assembly; 11 buttons; 111. keycap; 112. limit portion; 113. first bump; 12. elastic arm; 13. mounting seat; 131. base; 132. side; 133. second bump 134. Card hole; 135. Card slot; 14. Safety arm; 141. Side arm; 142. Beam; 15. Outer convex part; 151. Resisting surface; 152. Guide surface; 153. Bevel; 16. Cross top Column; 161. Transmission surface; 162. Guide surface;

20. Shell; 21. Second side wall; 22. First side wall; 221. Button hole; 222. Guide slot; 23. Limiting rib; 24. Mounting column; 25. Card hook;

30. Circuit board assembly; 31. Circuit board; 311. Circuit board edge; 32. Switch device; 321. Contact.

detailed description

The principles and features of the present invention will be described below in conjunction with the drawings. The examples given are only used to explain the present invention, not to limit the scope of the present invention.

Example one

With reference to FIGS. 1-2, this embodiment provides a key structure, which includes a key assembly 10, a housing 20, and a circuit board assembly 30. The key assembly 10 is installed inside the casing 20 of the terminal. The casing 20 may be a front panel casing of the terminal. The circuit board assembly 30 is welded with at least one switching device 32. When assembling, the key assembly 10 is assembled with the device casing 20 first, and then assembled with the circuit board assembly 30 as a component. The material of the key assembly 10 and the device casing 20 of this embodiment are both plastic, which has good structural stability and deformability.

The housing 20 of this embodiment includes a first side wall 22 (side wall in the figure) and a second side wall 21 (bottom wall in the figure) which are angled to each other, wherein the first side wall 22 is provided with a key hole 221 and In the first connection portion, the second side wall is provided with a second connection portion, and the plurality of key holes 221 are in one-to-one correspondence with the plurality of keys 11 described below.

The key assembly 10 of this embodiment includes a mounting frame and a key 11. The mounting frame and the key may be detachably connected or fixedly connected or integrally formed. The mounting frame includes a mounting base 13 and a safety arm 14 on opposite sides of the key. The mounting base 13 It is connected to the safety arm 14 through two connecting arms at opposite ends of the button 11. In this embodiment, there are a plurality of keys. Each key is provided with a key cap 111 and two symmetrical two elastic arms 12. The key cap 111 is connected to the limiting portion 112 above the key cap 111, and a cross top post 16 is provided on the back of each key cap 111. The key 11 is connected to the mounting base 13 through its elastic arm 12; the key cap 111 passes through the key hole 221 on the first side wall 22 and is exposed to the outside of the device. When the user presses the operation, the key cap 111 is displaced and its back The cruciform top post 16 will trigger the switching device 32 on the circuit board 31, and at the same time, the elastic arm 12 is elastically deformed. After the pressing action is completed, the elastic arm 12 drives the key cap 111 to rebound and return to position.

The safety arm 14 of this embodiment includes two arms 141 connected to the mounting base 13 and a beam 142. The beam 142 is located at the rear of the key 11 and is opposite to the limiting portion 112 above the key cap 111 at a certain distance, and when the limiting portion 112 or the beam 142 is deformed, the two can resist each other.

In addition, in this embodiment, an outer convex portion 15 is further provided on the side of the safety arm 14 away from the first side wall 22. The outer convex portion 15 is located on the back of the safety arm 14, and includes at least one that is sequentially connected in the direction of approaching the second side wall 21. The resisting surface 151, the guide surface 152 and the inclined surface 153, the limiting portion 112, the crossbeam 142 and the outer convex portion, during assembly, the circuit board assembly 30, the outer convex portion 15 and the limiting portion 112 sequentially abut against each other, making the cross of the button resist A predetermined interval is formed between the contacts on the switching device of the circuit board assembly 30. The design of the outer convex portion 15 can effectively prevent the problem of key failure caused by scratching during the assembly of the circuit board assembly. The specific function and protection principle of the outer convex portion 15 will be described in detail in the specific installation process below.

The mounting base 13 of this embodiment is installed on the inner side of the first side wall 22 of the device by mechanical fixing. The mechanical fixing method is specifically snap-fitting, that is, a first matching portion and a second matching portion are provided on the mounting base; Wherein, the first matching portion is snap-fitted with the above-mentioned first connecting portion, the second matching portion is snap-fitted with the above-mentioned second connecting portion, the first connecting portion may be a hook 25, and the first matching portion is a hook With the matching hole 134, the second connecting portion may be the mounting post 24, and the second matching portion is a receiving slot 135 adapted to the mounting post. Of course, the structural forms of the connecting part and the mating part are not limited to this, as long as the two can be engaged and connected and facilitate disassembly.

As shown in FIG. 3, the installation method of the key assembly 10 of this embodiment is that the key cap 111 is first passed through the key hole 221 of the first side wall 22, so that the first bump 113 and the second bump 133 are in close contact with the first A side wall 22, and then the mounting seat 13 is fixed. At least one hook 25 is provided on the side wall of the housing. When the key cap 111 passes through the key hole 221, the first bump 113 and the second bump 133 are closely attached to the first side wall 22, the mounting base 13 is designed by The buckle position 134 is just under the hook 25, so as to limit the displacement of the mounting base 13 in the Z direction. Finally, the mounting base 13 is fixed in the X and Y directions. At least two clamping slots 135 are provided on the base 131 where the mounting base 13 cooperates with the second side wall 21 (the top/bottom surface of the casing), and at their corresponding positions, the second side wall is provided with mounting posts 24 and key clamping slots 135 The diameter is slightly larger than the diameter of the housing mounting post 24. When the key cap 111 and the snap position 134 are installed in place, the base 131 is slanted over the mounting post 24, and the base 131 is forcibly pressed down by the elasticity of the plastic material to form two phases of the locking groove 135 and the mounting post 24 The line contact of the cylindrical surface is cut, and the mounting seat 13 is clamped and cannot move in any direction.

When the key assembly 10 includes a plurality of keys, a limiting rib 23 is provided on the first side wall 22 to allow a small and movable gap between the limiting rib 23 and the side wall 141 of the key assembly 10 to assist the key assembly 10 Perform a top-down translational installation, guiding multiple keycaps 111 to align and enter their corresponding keyholes 221 at the same time, improving assembly efficiency.

A guide groove 222 is provided inside the first side wall 22, on the one hand, it can avoid scratching the appearance of the key cap 111 during the assembly process, and on the other hand, it can also play a guiding role, helping multiple key caps 111 to be easily aligned into their respective key holes 221, improve product appearance and assembly efficiency.

The first bump 113 and the second bump 133 are provided to facilitate accurate fine adjustment of important dimensions of the injection mold of the key assembly 10. Adjusting the height of the first bump 113 can ensure that the height of the key cap 111 protruding from the appearance surface of the product casing 20 is accurate, and avoid tilting. Adjusting the height of the second bump 133 can ensure that the mounting seat 13 is tightly fixed and avoids shaking.

The following describes the specific assembly process of the key structure of this embodiment in detail:

First, the key assembly 10 and the device casing 20 are assembled to make the two into one assembly. As shown in FIG. 4, after the key is assembled in place, the key cap 111 passes through the key hole 221 of the casing, the first bump 113 and the second bump 133 Adjacent to the first side wall 22, the locking position 134 and the locking groove 135 respectively clamp the hook 25 and the mounting post 24 of the housing 20, and the beam 142 maintains a certain distance from the limiting portion 112 of the front key 11 in the initial state.

Then, the circuit board assembly 30 is assembled into the device housing assembly from top to bottom. The circuit board edge 311 first contacts the guide surface 152 of the outer convex portion 15, slides along the guide surface 152 and pushes the beam 142 forward, and when the circuit board edge 311 slides to the abutment surface 151 of the outer convex portion 15, the beam 142 resists The limiting portion 112 of the button 11 in front of it, makes the first bump 113 in front of the limiting portion 112 close to the inner side of the first side wall 22, that is, forcing the button 11 to stay at its most front end position, eliminating any backward tilt of the button 11 Displacement, thereby ensuring that when the circuit board assembly 30 continues downward and the switching device 32 reaches behind the cross top post 16, the two maintain the designed gap. The reason for this design is that the back of the existing plastic key button is provided with a cross-top post as a trigger structure. For the consideration of the deformation of the elastic arm and the feel of the key, it is hoped that the distance between the cross-top post and the front end of the switching device on the circuit board As small as possible, usually only designed to 0.2 ~ 0.3mm. As a result, during the assembly of the circuit board, as long as there is a slight backward deformation of the button part, the cruciform top post will be scratched by the contact of the front end of the switching device, resulting in an irreversible deformation of the corresponding button. When the device has multiple buttons in parallel, it is extremely difficult to avoid one or several buttons being scratched and deformed, which may cause assembly failure or even product quality problems.

Therefore, the structural design of the outer convex portion 15 and the limiting portion 112 of the above-mentioned beam 142 is carried out. The essence of this design is to design the outer convex portion 15 to push the switching device 32 right before the cross top post 16 is assembled. The key 11 does not tilt backward. The purpose is to solve the problem that the cruciform top post 16 is close to the switching device 32 and is easy to be scratched during the assembly process, thereby avoiding unrecoverable backward tilt deformation of the key 11 and collision damage of the contact 321 of the switching device.

During assembly of the circuit board assembly 30, the lateral beam 142 is pushed to elastically deform the side arm 141. When the assembly is completed, the lateral arm 141 drives the lateral beam 142 to return backward until the inclined surface 153 below the outer convex portion 15 abuts against the edge of the circuit board 311, by designing that the deformation of the side arm 141 is not completely released when it is in the final position, the safety arm 141 can be ensured to be stable and sloshing noise can be avoided.

When the keycap 11 is subjected to an inappropriate excessive pressing force, the stroke of the limiting portion 112 will be limited by the beam 142 due to the outer convex portion 15 abutting the circuit board edge 311, that is, the stroke of the key 11 will be limited. To avoid the cross top post 16 pushing the switching device contact 321 beyond the specified stroke, the switching device 32 is damaged by overvoltage.

When the circuit board assembly 30 is assembled to the final position, the circuit board edge 311 abuts the limiting rib 23, thereby restricting the movement of the circuit board assembly 20 in the direction of the key assembly 10, thereby preventing the switching device contact 321 from being crossed by the cross top post 161 Triggered in advance.

In summary, the key structure disclosed in the present invention is mechanically fixed, which can realize hot-melt-free and screw-free installation, does not bring additional parts and installation costs, and is reliable in installation, no looseness, and no shaking noise. The key structure also has a unique safety arm design, which can effectively prevent the key failure caused by assembly, reduce the product assembly failure rate, and save product quality costs.

Example 2

This embodiment provides a terminal (not shown in the figure), which may be any existing electronic communication device, which has a key structure as described in Embodiment 1, and other components of the terminal are related to the prior art Similarly, this embodiment does not make too much description.

According to the key structure provided by the present invention, during the assembly process of the whole machine, the safety arm can be pushed by the circuit board assembly until it presses against the key limit portion, so that the key is close to the product shell, that is, the key's tipping deformation to the direction of the circuit board returns to zero In order to avoid the deformation and damage of the button cross top post by the circuit board assembly during the assembly process. The key structure scheme of the present invention can effectively prevent the key failure caused by assembly, reduce the defective assembly rate of the whole product, and save the product quality cost.

In the description of the present invention, it should be understood that the terms "upper", "lower", "left", "right", "inner", "outer", etc. indicate the orientation or positional relationship based on the drawings The orientation or positional relationship is only for the convenience of describing the present invention and simplifying the description, but does not indicate or imply that the device referred to must have a specific orientation, be constructed and operated in a specific orientation, and should not be construed as limiting the present invention.

In addition, the terms “first” and “second” are used for description purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is more than two, unless otherwise specifically limited.

In the present invention, unless otherwise clearly specified and defined, the terms "installation", "connection", "connection" and other terms should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or integrated Wait. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention according to specific situations.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above-mentioned embodiments are exemplary and cannot be construed as limitations to the present invention, and those of ordinary skill in the art within the scope of the present invention can The embodiments are changed, modified, replaced, and modified.

Claims

A key structure, including:

Shell, the shell is provided with key holes;

A key assembly, the key assembly includes a key that cooperates with the key hole, a safety arm and a mounting seat that are respectively located on opposite sides of the key and connected to each other; wherein the key is elastically connected to the mounting seat, so The mounting base is connected to the housing; a limit portion is provided on a side of the key close to the safety arm, and there is a preset distance between the limit portion and the safety arm, and the safety arm When the deformation in the direction of the limit portion occurs, the two can resist each other, and the outer side of the safety arm away from the limit portion is provided with an outwardly protruding portion;

A circuit board assembly, the circuit board assembly is connected to the casing, and is located on a side of the key assembly away from the casing; during assembly, the circuit board assembly, the convex portion and the limiting portion Sequentially offset, and form a preset interval between the key and the circuit board assembly.
The key structure according to claim 1, wherein the outer convex portion has a guide surface, an abutment surface and an inclined surface which are sequentially connected in a direction close to the mounting seat; the circuit board assembly is sequentially connected with the The guide surface, the abutment surface and the inclined surface are offset, and move to the assembly position along the preset direction of the guide surface, the abutment surface and the inclined surface, and when the circuit board assembly moves to the abutment surface, the safety arm pushes The limiting portion is in contact with the casing.
The key structure according to claim 2, wherein the guide surface and/or the inclined surface and the outer surface of the circuit board assembly close to the key assembly form an angle with each other.
The key structure according to claim 2, wherein the resisting surface is parallel to the outer surface of the circuit board assembly close to the key assembly.
The key structure according to claim 1, wherein the key includes a key cap, and the key cap extends out of the limit portion in a direction away from the mounting seat.
The key structure according to claim 5, wherein the key cap and the mounting base are connected by an elastic arm.
The key structure according to any one of claims 1-6, wherein the housing includes a first side wall and a second side wall that are angled to each other; wherein the first side wall is provided with the key hole and A first connecting portion, the second side wall is provided with a second connecting portion; the mounting seat is provided with a first matching portion and a second matching portion; wherein, the first matching portion is locked with the first connecting portion The second engagement portion is snap-fitted with the second connection portion.
The key structure according to claim 7, wherein the first connection portion is a hook, and the first matching portion is a hole that fits the hook; or, the first connection portion is For the card hole, the first matching portion is a card hook adapted to the card hole.
The key structure according to claim 7, wherein the mounting seat is installed on the second side wall between the first side wall and the second connecting portion, and the mounting seat is provided with Describe the second mating part.
The key structure according to claim 9, wherein the second connecting portion is a mounting post provided on the second side wall, and the second fitting portion is a card slot adapted to the mounting post .
The key structure according to claim 7, wherein the key assembly is provided with a bump against the first side wall.
The key structure according to claim 11, wherein the bump includes a first bump provided on the limiting portion and a second bump provided on the mounting seat.
The key structure according to claim 7, wherein a guide groove matched with the key is provided on the first side wall.
The key structure according to claim 7, wherein two limiting ribs are respectively provided on both sides of the first side wall, and the key assembly is located between the two limiting ribs.
The key structure according to any one of claims 1-7, wherein the number of the key hole and the key is multiple, and the two are connected in one-to-one correspondence.
A terminal, wherein it has a key structure according to any one of claims 1-14.