CN114584639A

CN114584639A - Cover plate, circuit board fixing assembly and mobile terminal

Info

Publication number: CN114584639A
Application number: CN202011383977.8A
Authority: CN
Inventors: 尚群超; 曾伦
Original assignee: Beijing Xiaomi Mobile Software Co Ltd
Current assignee: Beijing Xiaomi Mobile Software Co Ltd
Priority date: 2020-11-30
Filing date: 2020-11-30
Publication date: 2022-06-03

Abstract

The disclosure relates to a cover plate, a circuit board fixing assembly and a mobile terminal. The cover plate is used for fixing a circuit board, and comprises: the body is used for covering the circuit board; a connecting part bent downward from the body; the limiting part is bent from the connecting part to the outer side of the body; and the bent part is reversely bent from the tail end of the limiting part. Through this disclosed terminal inflection mode at spacing portion for terminal burr is inboard towards, like this, in the equipment process, can effectively avoid terminal burr towards the risk of outside puncture battery.

Description

Cover plate, circuit board fixing assembly and mobile terminal

Technical Field

The disclosure relates to the technical field of terminals, in particular to a cover plate, a circuit board fixing assembly and a mobile terminal.

Background

With the continuous progress of science and technology, the functions of terminal products are more and more, and the convenience and the grippability are also particularly important. Thus, placing a greater number of components in a limited product space is the subject of ongoing research.

End products typically have circuit boards. Taking a mobile phone as an example, the mobile phone includes a middle frame, large and small boards (a main circuit board and an auxiliary circuit board) fixed on the middle frame, and a battery. Wherein, the small plate is fixed on the middle frame through the cover plate. Specifically, the cover plate is provided with a steel sheet which extends out of a part of the cover plate and is matched with the middle frame for limiting. The protruding portion of the steel sheet is usually sharp, and during the assembly process, there is a risk of easily puncturing the battery, and in severe cases, a safety accident may be caused.

Disclosure of Invention

To overcome the problems in the related art, the present disclosure provides a cover plate, a circuit board fixing assembly and a mobile terminal.

According to a first aspect of the embodiments of the present disclosure, there is provided a cover plate for fixing a circuit board, the cover plate including: the body is used for covering the circuit board; a connecting part bent downward from the body; the limiting part is bent from the connecting part to the outer side of the body; and the bent part is reversely bent from the tail end of the limiting part.

In one embodiment, the bending portion is bent from the end of the position-limiting portion by an angle of 180 degrees.

In one embodiment, the connecting portion is perpendicular to the body and the bending portion, and the transition angle between the connecting portion and the body is a right angle, and the transition angle between the connecting portion and the bending portion is a right angle.

In one embodiment, the length of the limiting part is greater than or equal to 0.45 mm.

In one embodiment, the length of the bending part is between 0.45mm and 0.55 mm.

In one embodiment, the distance between the connecting portion and the circuit board is greater than or equal to 1 mm.

In an embodiment, the end of the bending part is a smooth curved surface.

According to a second aspect of the embodiments of the present disclosure, there is provided a circuit board fixing assembly, including a middle frame, the middle frame being provided with a limiting groove; a cover plate as described in any one of the embodiments of the first aspect above; wherein at least one part of the limiting part is positioned in the limiting groove.

In an embodiment, the bending portion is a smooth curved surface. The limiting groove comprises a top wall, a bottom wall and a side wall; the limiting part is abutted against the top wall, and the distance between the bottom surface of the bending part and the bottom wall is greater than or equal to 0.3 mm.

In an embodiment, the bending portion is a smooth curved surface. The distance between the front end face of the bending part and the side wall is 0.45-0.55 mm.

According to a third aspect of the present disclosure, there is provided a mobile terminal comprising: the circuit board fixing assembly according to any one of the embodiments of the second aspect.

The technical scheme provided by the embodiment of the disclosure can have the following beneficial effects:

through the terminal mode of turning over at spacing portion for terminal sharp limit is towards the inboard, like this, in the equipment process, can effectively avoid terminal sharp limit to pierce through the risk of battery towards the outside.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and together with the description, serve to explain the principles of the disclosure.

Fig. 1 is a partial structural diagram of a mobile terminal in the related art.

Fig. 2 is a schematic structural diagram of a mobile terminal shown according to an exemplary embodiment of the present disclosure.

Fig. 3 is a partial structural diagram of a mobile terminal shown according to an exemplary embodiment of the present disclosure.

Fig. 4 is a partial structural schematic view of a cover plate according to an exemplary embodiment of the present disclosure.

Fig. 5 is a partial structural schematic view of a circuit board securing assembly shown according to an exemplary embodiment of the present disclosure.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the exemplary embodiments below are not intended to represent all implementations consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present disclosure, as detailed in the appended claims.

Fig. 1 is a partial structural diagram of a mobile terminal in the related art.

As shown in fig. 1, the mobile terminal in the related art includes a middle frame 210, a circuit board mounted on the middle frame 210, and a battery adjacent to the circuit board. The circuit board is fixed to the middle frame through the cover plate 220 to effectively protect the circuit board.

The circuit board is used as a sub-board (small board) of the mobile terminal and is electrically connected with elements such as a battery, a charging interface and the like. The cover plate 220 is provided with a plurality of mounting holes. The middle frame is provided with a plurality of mounting columns corresponding to the mounting holes. The cover plate 220 is formed by matching a steel plate with an injection molding piece, so that the strength of the cover plate structure is improved.

During assembly, the circuit board is placed on the small plate area of the middle frame, then the cover plate is covered on the circuit board, and the plurality of screws 230 penetrate through the mounting holes in the cover plate and are screwed into the mounting columns respectively to lock and fix the cover plate.

In order to ensure the stability of the circuit board fixing, the position where the screw 230 fastens the cover plate should be compact, for example, the screw fastens at the edge and the middle part of the cover plate.

In the above-described system, there are problems as follows:

1) the plurality of mounting posts on the middle frame 210 have a complex structure, occupy a large amount of space, and are not beneficial to stacking other devices.

2) When the cover plate 220 is mounted on the middle frame, the mounting holes are aligned with the mounting posts on the middle frame, and the positioning is difficult.

3) The circuit board is fixed on the middle frame through the cover plate 220 and only depends on the fastening of screws, so that the steel plate is limited in thickness and low in strength, and the cover plate 220 still has the risk of deformation at the position with larger screw distance, so that the circuit board is unstable in fixation.

In the related art, the edge of the cover plate 220 is bent outwards twice to form a buckling structure, the buckling structure is a steel plate protruding outwards, the steel plate is matched with a limiting groove on the middle frame 210 to limit the cover plate, so that the number of screws at the position of the buckling structure can be reduced, the number of corresponding mounting columns on the middle frame is reduced, and more space can be provided for stacking other devices.

However, the above-described method has the following problems:

1) since the cover plate is typically only 0.2mm thick, the front end of the snap feature (protruding steel plate) is very sharp and burred. In assembly, on the one hand, fingers are easily cut if carelessness is not taken. In another aspect. The small plate is usually adjacent to the battery, and the battery is easy to puncture if the small plate is careless, and a safety accident can be caused in a serious case.

2) The buckle structure protrudes outwards from the cover plate, so that the space of the mobile phone is undoubtedly occupied, and the space is wasted.

3) The excessive bending angle is generally a rounded angle, and in the manufacturing process, it is difficult to grasp the dimensional accuracy, resulting in poor stability when the circuit board is fixed by the cover plate.

4) Limited by the thickness of the whole machine (terminal), the thickness of the cover plate 220 is limited, the buckling strength is weak, and the limiting and fixing effect is poor.

In view of the above problems, the embodiments of the present disclosure provide a cover plate for fixing a circuit board, in which after the cover plate is bent for three times, the end edge is in a reverse-folded state, so as to effectively prevent the risk of puncturing the battery, and improve the strength of the cover plate, so that the circuit board is more stably fixed.

Fig. 2 is a schematic structural diagram of a mobile terminal shown according to an exemplary embodiment of the present disclosure. Fig. 3 is a partial structural diagram of a mobile terminal shown according to an exemplary embodiment of the present disclosure.

As shown in fig. 2 and 3, the cover plate 10 of the present disclosure may be applied to a mobile terminal 100. The mobile terminal 100 may be a smart phone, a tablet computer, a notebook computer, a personal digital assistant, a smart watch, a smart bracelet, or the like. The present disclosure is illustrated by taking a smart phone as an example, but the present disclosure is not limited thereto.

The mobile terminal 100 may include a case forming an external appearance, such as a front case 102 and a rear case 101. The front case 102 and the rear case 101 are combined to form an accommodating space for accommodating various electronic components, such as a circuit board, e.g., a main board (large board), a sub board (small board), a speaker assembly, a battery, a camera assembly, and the like. The main board can be located at the upper part of the accommodating space, the battery can be located at the middle part of the accommodating space, and the auxiliary board can be located at the lower part of the accommodating space and electrically connected with the main board.

The mobile terminal 100 may further include a display screen disposed at the front of the terminal body, and a middle frame 20 supporting the rear of the display screen. A power key and a volume key may be further provided on the side of the middle frame 20. Functional devices such as a speaker for playing sound, a charging interface for supplying power to a battery, and a microphone for receiving user voice may be further installed at the bottom of the middle frame 20. These functional devices may be electrically connected to the sub-board (small board), among others. The battery may be installed at a middle position of the middle frame. The middle frame 210 may be independently disposed between the front case 101 and the rear case 102 as a supporting member, or may be integrally formed with the front case 101 or the rear case 102.

As shown in fig. 3 and 4, the cover plate 10 of the embodiment of the present disclosure includes a body 11, a connecting portion 12, a limiting portion 13, and a bending portion 14.

The body 11 is used for covering the circuit board and forming effective protection for the circuit board. The circuit board may be a sub-board (small board) of the mobile terminal. The body 11 may be a plate-shaped structure, and a plurality of mounting holes are formed thereon. The mounting holes correspond to mounting posts on the middle frame, and the screws 15 pass through the mounting holes to fasten the cover plate 10 to the middle frame 20. Illustratively, a plurality of mounting holes may be disposed about the periphery of the body 11.

A connecting portion 12 is formed by bending downward from the main body 11, and a stopper portion 13 is formed by bending outward from the main body 11 from the connecting portion 12. The connecting portion 12 is used for connecting the body 11 and the limiting portion 13, and the limiting portion 13 and the body 11 form a height difference. The limiting part 13 is used for matching with a limiting groove of the middle frame 20 to limit the circuit board (shown in fig. 5).

The bent portion 14 is formed by bending back from the end of the stopper 13. The bending portion 14 is bent toward the inner side of the body 11. Thus, the front end of the bending part 14 is an arc edge, and the tail end is a sharp edge. In one example, the bending portion 14 may be formed by bending upward from the end of the limiting portion 13. In another example, the bent portion 14 may be formed by bending downward from the end of the stopper 13.

The connecting portion 12, the stopper portion 13 and the bending portion 14 may form a snap structure. The snap structure can be one or more. That is, a snap structure is formed at one side or a plurality of sides of the body 11.

During the equipment, place the platelet installing zone on the center with the circuit board, then, insert the spacing inslot on the center with spacing portion 13 slant on the apron 10, then with body 11 lid on the circuit board, at this moment, because spacing portion 13 and spacing groove's cooperation, the mounting hole on the body 11 can be aligned with the erection column on the center, that is to say, can fix a position the apron through spacing portion 13. Then, screws 15 are screwed into the mounting posts of the middle frame 20 through the plurality of mounting holes of the body 11, respectively, to fix the cover plate, and thus the circuit board, to the middle frame.

In the cover plate 10 according to the embodiment of the present disclosure, the bent portion is formed by reversely folding the end of the stopper portion 13, the sharp edge at the end of the bent portion is on the inner side, and the arc-shaped edge at the front end of the bent portion is on the outer side. Like this, in the assembly process, can effectively avoid terminal sharp limit to have the risk of puncturing the battery towards the outside. In addition, the cover plate can be positioned through the limiting part 13, and compared with the traditional mode in which the two edges (the edge in the direction of X, Y in fig. 3) of the cover plate are positioned, the positioning is more convenient, and the assembly efficiency of the cover plate 10 can be effectively improved. Furthermore, through the arrangement of the limiting part 13, the number of screw fastening can be reduced, so that the number of mounting columns on the middle frame 20 is reduced, and more space is provided for stacking other devices.

In one embodiment, the angle of the bending portion 14 from the end of the positioning portion 13 is 180 degrees. Further, the limiting portion 13 includes a limiting surface and a back surface opposite to the limiting surface. The limiting surface is used for being abutted against the limiting groove of the middle frame. The bent portion 14 formed by folding the end of the position-limiting portion 13 back by 180 degrees may be attached to the back of the position-limiting portion 13. Like this, increased the thickness of spacing portion 13 for the intensity of spacing portion 13 is equivalent to the improvement one time of intensity when not buckling, and then makes the intensity of spacing portion 13 improve, and the steadiness of fixed circuit board can be strengthened, and the reliability improves. In addition, the length of the bent limiting part 13 is also reduced, and correspondingly, the size of the limiting groove on the middle frame 20 in the length direction (Y direction) can be reduced, so that the occupied space of the middle frame is reduced, and the stacking of other devices is facilitated.

Fig. 5 is a partial structural schematic view of a circuit board securing assembly shown according to an exemplary embodiment of the present disclosure. As shown in fig. 5, in an embodiment, to ensure the reliability of the position limiting portion 13, the length L1 of the position limiting portion 13 is greater than or equal to 0.45 mm. Thus, the stability of the limiting part 13 in contact with the middle frame limiting groove can be ensured, the possibility that the limiting part 13 falls off from the middle frame limiting groove due to too short time can be prevented, and the reliability of the cover plate 10 for fixing the circuit board can be improved.

In one embodiment, the dimension L4 of the bent portion 14 formed after the limiting portion 13 is bent can reduce the occupied space of the battery compartment as much as possible. The length of the bent portion 14 may be 0.45mm to 0.55mm, for example, the length of the bent portion 14 may be 0.5 mm. If the length of the bent portion 14 is too long, interference with other parts on the middle frame 20 may occur, and it is necessary to increase the space of the small plate region on the middle frame, and thus, it is necessary to encroach on the space of the battery compartment adjacent to the small plate region. Therefore, the dimension L4 of the bent portion 14 is not excessively long. According to the cover plate 10 disclosed by the embodiment of the disclosure, the size L4 of the bent part 14 is limited to be 0.45 mm-0.55 mm, so that the bent part 14 can be effectively prevented from interfering with other parts, the occupation of the battery compartment space is avoided, and the realization of a large-capacity battery is facilitated.

In one embodiment, the distance L5 between the connection portion 12 and the circuit board is greater than or equal to 1mm, such as 1.05 mm. During assembly, the limiting portion 13 of the cover plate 10 is obliquely inserted into the limiting groove of the middle frame 20 from the gap between the middle frame 20 and the circuit board, and in this installation process, a certain avoiding space needs to be reserved for the limiting portion 13, so that the limiting portion 13 is smoothly inserted into the limiting groove of the middle frame. The apron 10 of this embodiment sets up distance L5 between through connecting portion 12 and the circuit board to be more than or equal to 1mm, under the prerequisite of guaranteeing not additionally to occupy other device spaces, can ensure the spacing inslot of the smooth inserting center 20 of spacing portion 13 of apron 10, improves the convenience of equipment, improves the packaging efficiency.

In one embodiment, the connecting portion 12 is perpendicular to the body 11 and the bending portion 14, and the transition angle between the connecting portion 12 and the body 11 is a right angle, and the transition angle between the connecting portion 12 and the bending portion 14 is a right angle. That is, the corner where the body 11 is bent to form the connecting portion 12 and the corner where the connecting portion 12 is bent to form the bent portion 14 are both right-angled. That is, the connecting portion 12 and the bent portion 14 are formed by being bent at a right angle. In the prior art, the fillet bending mode is adopted, when processing, the fillet is excessive, the error in dimension is generated, and the dimensional accuracy of the connecting part 12 and the limiting part 13 is difficult to guarantee. Therefore, the cover plate 10 according to the embodiment of the present disclosure forms the connecting portion 12 and the bent portion 14 by bending at a right angle, so that the dimensional accuracy of the connecting portion 12 and the limiting portion 13 can be ensured, the machining dimension can be more easily controlled, and the reliability of the cover plate 10 for fixing and mounting the circuit board can be further improved.

In another example, the connecting portion 12 may be disposed at an angle to the body 11 and the stopper portion 13, respectively, i.e., the connecting portion 12 may be disposed non-perpendicular to the body 11 and the stopper portion 13, i.e., obliquely. For example, the position-limiting part 13 is parallel to the main body 11, and the connecting part 12 connected between the position-limiting part 13 and the main body 11 is inclined toward the outer side of the main body 11, so that the inclined connecting part 12 can enable the position-limiting part 13 to be more conveniently inserted into the position-limiting groove on the middle frame 20, and can reduce the space in the Z direction when the cover plate fixes the circuit board.

In one embodiment, the end of the bending portion 14 is a smooth curved surface. The bending portion 14 includes a front curved surface 141 and a tail sharp edge, and the front curved surface and the tail sharp surface of the bending portion 14 can be processed by a magnetic grinding process to remove burrs on the bending portion. In the manufacturing process, the assembling process and the subsequent maintenance process, the tail end is smooth and curved, so that assembly personnel or maintenance personnel can be prevented from being scratched by burrs, and the safety is improved.

According to a second aspect of the present disclosure, a circuit board fixing assembly is provided, which includes the middle frame 20 and the cover plate of any one of the embodiments of the first aspect.

As shown in fig. 5, the middle frame 20 is provided with a stopper groove, and at least a portion of the stopper portion 13 of the cover plate 10 is located in the stopper groove.

Set up spacing groove and spacing portion 13's cooperation through center 20, can fix a position the apron through spacing portion 13, compare in traditional mode, through the mode of two limits of apron (X, Y direction's limit in fig. 3) location, it is more convenient to fix a position, can effectively improve the packaging efficiency of apron 10. In addition, through the arrangement of the limiting part 13, the number of screw fastening can be reduced, so that the number of mounting columns on the middle frame 20 is reduced, and more space is provided for stacking other devices.

In one embodiment, the retaining groove includes a top wall 211, a bottom wall 212, and a side wall 213. The top wall 211 is opposite to the bottom wall 212, and the side walls 213 are connected to the top wall 211 and the bottom wall 212, respectively. The top wall 211 abuts against the stopper 13, for example, a stopper surface (upper surface) of the stopper 13. A distance L3 between the bottom surface of the bent portion 14 and the bottom wall 212 is greater than or equal to 0.3mm, for example, L3 is 0.33 mm.

During assembly, the limiting portion 13 on the cover plate 10 is obliquely inserted into the limiting groove of the middle frame 20 from the gap between the middle frame 20 and the circuit board, and the limiting groove of the middle frame 20 needs to reserve a certain avoiding space for the limiting portion 13, so that the limiting portion 13 can smoothly enter the limiting groove for installation. The subassembly is fixed to the circuit board of this embodiment, the spacing groove of center 20 provides a certain amount for the spacing portion entering of apron 10 dodges the space, and the distance L3 between the bottom surface of kink 14 and the diapire 212 is more than or equal to 0.33mm promptly, when can getting into the spacing groove for spacing portion 13, reserves certain space of dodging to, under the prerequisite of guaranteeing not additionally to occupy other device spaces, improve the convenience of equipment, improve the packaging efficiency.

In one embodiment, the distance between the front end surface of the bending portion 14 and the side wall 213 is between 0.45mm and 0.55 mm.

The front end face of the bent portion 14 is a curved surface formed by bending the stopper portion 13, and the distance L2 between the arc end of the curved surface and the side wall 213 is between 0.45mm and 0.55 mm. When the limiting portion 13 of the cover plate 10 is disposed in the limiting groove of the middle frame 20, if the front end surface of the bending portion 14 contacts and abuts against the side wall 213 of the limiting groove, the side surface of the limiting groove will form a reaction force against the bending portion 14, and the cover plate 10 deforms due to the reaction force. In order to prevent the deformation of the cover plate 10, after the cover plate 10 is assembled, a gap needs to be reserved between the front end surface of the bending portion 14 and the side wall 213, in the embodiment of the present disclosure, when the limiting portion 13 on the cover plate 10 is disposed in the limiting groove on the middle frame 20, the gap reserved between the front end surface of the bending portion 14 and the side wall 213 is between 0.45mm and 0.55mm, which can effectively prevent the deformation of the cover plate 10 caused by the interference between the bending portion 14 and the limiting groove, which affects the assembly risk, and improves the reliability of the assembly.

According to a third aspect of the embodiments of the present disclosure, there is provided a mobile terminal 100 including the circuit board fixing assembly of any one of the embodiments of the second aspect.

As shown in fig. 2, the mobile terminal 100 may include that the mobile terminal 100 may be a smart phone, a tablet computer, a notebook computer, a personal digital assistant, a smart watch, a smart bracelet, etc. The present disclosure is illustrated by taking a smart phone as an example, but the present disclosure is not limited thereto.

The mobile terminal 100 may include a case forming an external appearance, such as a front case 101 and a rear case 102. The front case 101 and the rear case 102 are combined to form an accommodating space for accommodating various electronic components such as a main board (large board), a sub board (small board), a speaker assembly, a battery, a camera assembly, and the like. The main board can be located on the upper portion of the accommodating space, the battery can be located in the middle of the accommodating space, and the auxiliary board can be located on the lower portion of the accommodating space and electrically connected with the main board.

The mobile terminal 100 may further include a display screen disposed at the front of the terminal body, and a middle frame 20 supporting the rear of the display screen. A power key and a volume key may be further provided on the side of the middle frame 20. Functional devices such as a speaker for playing sound, a charging interface for supplying power to a battery, and a microphone for receiving user voice may be further installed at the bottom of the middle frame 20. These functional devices may be electrically connected to the sub-board (small board), among others. The battery is arranged at the middle position of the middle frame. The middle frame 210 may be independently disposed between the front case 101 and the rear case 102 as a supporting member, or may be integrally formed with the front case 101 or the rear case 102.

The mobile terminal 100 provided by the present disclosure can improve the safety, convenience and reliability of circuit board fixation in the assembly process on the premise of ensuring the overall space utilization rate by configuring the circuit board fixing assembly of the present disclosure.

It is understood that "plurality" in this disclosure means two or more, and other terms are analogous. "and/or" describes the association relationship of the associated objects, meaning that there may be three relationships, e.g., a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship. The singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It will be further understood that the terms "first," "second," and the like are used to describe various information and that such information should not be limited by these terms. These terms are only used to distinguish one type of information from another and do not denote a particular order or importance. Indeed, the terms "first," "second," and the like are fully interchangeable. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present disclosure.

It will be further understood that the terms "central," "longitudinal," "lateral," "front," "rear," "upper," "lower," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship indicated in the drawings for convenience in describing the present embodiment and to simplify the description, but do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation.

It will be further understood that, unless otherwise specified, "connected" includes direct connections between the two without the presence of other elements, as well as indirect connections between the two with the presence of other elements.

It is further to be understood that while operations are depicted in the drawings in a particular order, this is not to be understood as requiring that such operations be performed in the particular order shown or in serial order, or that all illustrated operations be performed, to achieve desirable results. In certain environments, multitasking and parallel processing may be advantageous.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any variations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

It will be understood that the present disclosure is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A cover plate for fixing a circuit board, the cover plate comprising:

the body is used for covering the circuit board;

a connecting part bent downward from the body;

the limiting part is bent from the connecting part to the outer side of the body; and

and the bent part is reversely bent from the tail end of the limiting part.

2. The cover sheet according to claim 1,

the bending part is bent from the tail end of the limiting part by 180 degrees.

3. The cover sheet according to claim 1,

the connecting part is respectively vertical to the body and the bending part, the transition angle between the connecting part and the body is a right angle, and the transition angle between the connecting part and the bending part is a right angle.

4. The cover sheet according to claim 1,

the length of the limiting part is greater than or equal to 0.45 mm.

5. The cover sheet according to claim 1,

the length of the bending part is 0.45-0.55 mm.

6. The cover sheet according to claim 3,

the distance between the connecting part and the circuit board is larger than or equal to 1 mm.

7. The decking of claim 1,

the tail end of the bending part is a smooth curved surface.

8. A circuit board securing assembly, comprising:

the middle frame is provided with a limiting groove;

the cover sheet of any one of claims 1 to 7;

wherein at least one part of the limiting part is positioned in the limiting groove.

9. The circuit board securing assembly according to claim 8,

the limiting groove comprises a top wall, a bottom wall and a side wall;

the limiting part is abutted against the top wall, and the distance between the bottom surface of the bending part and the bottom wall is larger than or equal to 0.3 mm.

10. The circuit board securing assembly according to claim 9,

the distance between the front end face of the bending part and the side wall is 0.45-0.55 mm.

11. A mobile terminal, comprising:

a circuit board securing assembly as claimed in any one of claims 8 to 10.