Middle frame and electronic device

Abstract

This application provides a middle frame and an electronic device including this middle frame. The middle frame includes an integrally formed flat portion and a first recessed portion. The first recessed portion is recessed inward relative to the first surface of the flat portion to form a first groove, and the opening of the first groove is located on the first surface; the first recessed portion includes a bottom wall, a first side wall, and a second side wall. The orientation of the bottom wall is the same as that of the first surface. The first side wall and the second side wall intersect with the bottom wall respectively, and the first side wall and the second side wall are connected; in a first direction, the opening formed by the first side wall and the second side wall gradually becomes larger, and during the die-casting process of the middle frame, the first direction is parallel to the flow direction of the die-casting material. The thickness of the flat portion of the middle frame provided in this application is relatively thin.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of electronic devices, and in particular, to a middle frame and an electronic device. Background Art

[0002] In the field of consumer electronic devices, especially mobile phones, the thickness of the whole machine is one of the key factors affecting the delicacy of the product. In the traditional technology, the middle frame includes a flat portion and a recessed portion that is recessed relative to the flat portion. The groove of the recessed portion is used to accommodate other components of the electronic device to reduce the overall thickness of the electronic device. However, after the middle frame is formed by die casting, the thickness of the flat portion is relatively thick, which affects the overall thickness of the electronic device. Summary of the Invention

[0003] The embodiments of the present application provide a middle frame and an electronic device including this middle frame. The middle frame includes an integrally formed flat portion and a recessed portion. The recessed portion is recessed relative to the flat portion to form a groove, and the thickness of the flat portion is relatively thin.

[0004] In a first aspect, the present application provides a middle frame. The middle frame is prepared by a die-casting process. The die-casting forming process is a casting method in which molten material is filled into a mold cavity at high speed under the action of high pressure and the material solidifies under pressure to form a die-cast part. In this embodiment, the middle frame is prepared by a die-casting forming process, which not only reduces the cost of the middle frame but also improves the forming efficiency of the middle frame.

[0005] The middle frame includes an integrally formed flat portion and a first recessed portion. The first recessed portion is recessed inward relative to the first surface of the flat portion to form a first groove. The opening of the first groove is located on the first surface. The first recessed portion includes a bottom wall, a first side wall, and a second side wall. The orientation of the bottom wall is the same as the orientation of the first surface. The first side wall and the second side wall intersect with the bottom wall respectively, and the first side wall and the second side wall are connected. In a first direction, the opening formed by the first side wall and the second side wall gradually becomes larger, and in the process of die-casting the middle frame, the first direction is parallel to the flow direction of the die-casting material.

[0006] In this embodiment, in the first direction, the opening formed by the first side wall and the second side wall gradually becomes larger, and the direction of the opening is parallel to the material flowing during the die-casting of the middle frame. The material gradually disperses along the mold cavity side walls corresponding to the first side wall and the second side wall, reducing the resistance of the mold cavity side walls corresponding to the first side wall and the second side wall to the material flow, reducing the risk of cold material easily generated at the slag discharge side rib position, and avoiding the relatively thick thickness of the flat portion in the middle frame, which is beneficial to the overall thinning of the middle frame.

[0007] Among them, in the flow direction of the material, the smaller the angle formed by the first side wall and the second side wall, the smaller the angle formed by the first side wall or the second side wall and the flow direction of the material, and the smaller the flow resistance of the first side wall or the second side wall to the material. It can be understood that when the first side wall or the second side wall is perpendicular to the flow direction of the material, or when the first side wall or the second side wall forms an acute angle with the flow direction of the material, part of the structure of the first side wall or the second side wall deviates from the flow direction of the material, resulting in a larger flow resistance of the first side wall or the second side wall to the material.

[0008] In a possible implementation manner, the angle formed by the first side wall and the second side wall is an acute angle.

[0009] This application does not limit the specific angle formed by the first side wall and the second side wall. Exemplarily, the angle formed by the first side wall and the second side wall is less than or equal to 80 degrees.

[0010] In the embodiment of this application, the angle formed by the first side wall and the second side wall is an acute angle, and the angle formed by the first side wall and the second side wall is relatively small. During the die-casting process of the middle frame, the flow resistance of the first side wall and the second side wall to the material is relatively small, which further reduces the flow resistance of the groove wall of the first groove to the material, and is more conducive to reducing the thickness of the flat part.

[0011] In a possible implementation manner, the area of the bottom wall is relatively large, which increases the bonding area between the middle frame and the circuit board, thereby ensuring the stability of the bonding layer for bonding the circuit board and the middle frame. Exemplarily, the angle formed by the first side wall and the second side wall is greater than or equal to 15 degrees, so as to avoid a relatively small area of the bottom wall caused by a relatively small angle formed by the first side wall and the second side wall. It can be understood that the angle formed by the first side wall and the second side wall should not be too small or too large.

[0012] Among them, this application does not limit the specific angle of the acute angle formed by the first side wall and the second side wall, and those skilled in the art can design it according to actual needs.

[0013] In a possible implementation manner, the shape of the bottom wall includes a quadrilateral or a triangle, etc. Exemplarily, the shape of the bottom wall includes a rhombus or an equilateral triangle.

[0014] In this embodiment, when the opening formed by the first side wall and the second side wall gradually becomes larger in the first direction, the shape of the bottom wall can be a triangle or a parallelogram. In other embodiments, the bottom wall can also be in other shapes, such as a pentagon or a hexagon, etc., and this application does not limit this.

[0015] In a possible implementation, the first recessed portion is recessed relative to the flat portion to form a second recessed portion. The opening of the second recessed portion is in the same direction as the opening of the first recessed portion. The first recessed portion is located in the second recessed portion, and the depth of the first recessed portion is greater than the depth of the second recessed portion. The first recessed portion and the second recessed portion are used to accommodate different components in the electronic device.

[0016] In this embodiment, the middle frame is provided with a first groove and a second groove, and the first groove is located in the second groove. Both the first groove and the second groove are used to accommodate components in the electronic device, so that the overall thickness of the electronic device using the middle frame is small.

[0017] In a possible implementation, the flat portion is provided with a second surface disposed opposite to the first surface. The first groove is recessed from the first surface toward the second surface, and the side of the bottom wall away from the first surface is convex relative to the second surface. It can be understood that when the groove depths of the first grooves are equal, when the side of the bottom wall of the first groove away from the first surface is convex relative to the second surface, the bottom wall of the first groove is thicker.

[0018] In this embodiment, the bottom wall of the first groove is protruded relative to the second surface on the side away from the first surface, thereby increasing the thickness of the bottom wall of the first groove. During the molding process of the middle frame, the material encounters less resistance along the mold cavity corresponding to the first groove, thereby reducing the risk of cold material being easily generated at the slag discharge side bone position, and avoiding the thickness of the flat portion of the molded middle frame being too thick, thereby facilitating reducing the thickness of the flat portion in the middle frame.

[0019] In a possible implementation, the middle frame includes a first plate, a second plate, and a third plate connected in sequence, and the first plate, the second plate, and the third plate are used to carry different components. The second plate includes a first end and a second end that are arranged opposite to each other, the first end is connected to the first plate, the second end is connected to the third plate, and the second groove extends from the first end to the second end. There are multiple first grooves, and the multiple first grooves are arranged at intervals and are all located in the second groove.

[0020] Exemplarily, the multiple first grooves are used to accommodate multiple adhesive layers in a one-to-one correspondence, and the multiple adhesive layers are used to bond with different parts of the first recessed portion to improve the stability of the middle frame and the corresponding adhesive member. The shapes of the multiple first grooves can be the same or different, and this application does not limit this. The number of first grooves is also not limited in this application.

[0021] In a possible implementation, the middle frame further includes a second recessed portion. The second recessed portion is integrally formed with the flat portion, and the second recessed portion is recessed relative to the flat portion to form a third groove and a fourth groove. Both the third groove and the fourth groove are recessed from the side of the first surface toward the second surface, the fourth groove is located in the third groove, and the depth of the recess of the fourth groove is greater than the depth of the recess of the third groove.

[0022] In this embodiment, the middle frame is further provided with a second recessed portion integrally formed with the flat portion. The second recessed portion is used to accommodate other components in the electronic device, such as a connector. The connector is accommodated in the middle frame so that the thickness of the connector and the middle frame can be reused, reducing the overall thickness of the electronic device.

[0023] Wherein, in the first direction, the third groove and the second groove are staggeredly arranged, and in the second direction, the fourth groove and the first groove are staggeredly arranged; wherein, the second direction is perpendicular to the first direction.

[0024] In this embodiment, the fourth groove and the first groove are staggeredly arranged in both the first direction and the second direction, reducing the overlapping area between the fourth groove and the first groove, avoiding the double or multiple blockages of the material flow by the mold cavity in the same direction during the molding process of the middle frame, reducing the risk of cold material at the slag discharge side rib position of the mold cavity, and thus further reducing the thickness of the flat portion.

[0025] In a possible implementation, the shape of the fourth groove is the same as the shape of the first groove, and in the first direction, the openings formed by the two adjacent side walls of the fourth groove gradually become larger. Exemplarily, the bottom walls of both the fourth groove and the first groove are rhombic. The groove depth of the fourth groove is the same as the groove depth of the first groove, and the groove depth of the third groove is the same as the groove depth of the second groove.

[0026] In this embodiment, the shape of the fourth groove is the same as the shape of the first groove, and the openings formed by the two adjacent side walls of the fourth groove gradually become larger. During the die-casting molding process of the middle frame, not only the blockage of the material flow by the mold cavity structure corresponding to the first recessed portion is reduced, but also the blockage of the material flow by the mold cavity structure corresponding to the second recessed portion is reduced, further reducing the risk of cold material easily generated at the slag discharge side rib position, and being more conducive to thinning the flat portion.

[0027] In other possible implementations, the shape of the fourth groove may also be different from the shape of the first groove, and the present application does not limit this. For example, the bottom wall of the first groove is rhombic, and the bottom wall of the fourth groove is rectangular.

[0028] In a second aspect, the present application further provides a middle frame. The middle frame is prepared by a die-casting process. The middle frame includes an integrally formed flat portion and a first recessed portion, the first recessed portion is recessed relative to the flat portion to form a first groove, and the flat portion is provided with a first surface and a second surface disposed opposite to each other. The first surface faces the battery, the first groove is recessed from the first surface toward the second surface, and the bottom wall of the first groove is convex relative to the second surface on the side away from the first surface.

[0029] It can be understood that when the groove depths of the first grooves are equal, when the side of the bottom wall of the first groove facing away from the first surface is convex relative to the second surface, the bottom wall of the first groove is thicker.

[0030] In this embodiment, the bottom wall of the first groove is protruded relative to the second surface on the side away from the first surface, thereby increasing the thickness of the bottom wall of the first groove. During the molding process of the middle frame, the material encounters less resistance along the mold cavity corresponding to the first groove, thereby reducing the risk of cold material being easily generated at the slag discharge side bone position, and avoiding the thickness of the flat portion of the molded middle frame being too thick, thereby facilitating reducing the thickness of the flat portion in the middle frame.

[0031] In a third aspect, the present application provides an electronic device. The electronic device includes a battery and a middle frame described in any one of the first aspect or the second aspect, and the battery is installed in the middle frame. The projection of the battery on the middle frame covers the flat part and the recessed part. The battery is used to provide power for various components inside the electronic device. Exemplarily, the battery is carried in the middle area of ​​the middle frame.

[0032] In a possible implementation, the electronic device further includes a circuit board and an adhesive layer. The projection of the circuit board on the middle frame overlaps at least partially with the first recessed portion. The adhesive layer is connected between the circuit board and the first recessed portion, and the adhesive layer is accommodated in the first groove.

[0033] In this embodiment, the adhesive layer is used to fix the circuit board to the middle frame. The present application does not limit the material used for the adhesive layer, and those skilled in the art can design it according to actual needs. For example, the adhesive layer can be a double-sided adhesive.

[0034] In this embodiment, the circuit board and the adhesive layer are both accommodated in the accommodation space formed by the first recessed portion, and the thickness of the circuit board and the adhesive layer is reused with the thickness of the middle frame, thereby reducing the overall thickness of the electronic device.

[0035] In a fourth aspect, the present application further provides an electronic device. The electronic device comprises a battery, a display screen, a middle frame and an auxiliary component, wherein the battery and the display screen are both mounted on the middle frame, and the battery and the display screen are respectively located on two opposite sides of the middle frame, and the auxiliary component is located between the middle frame and the display screen;

[0036] The middle frame includes an integrally formed flat portion and a first recessed portion. The first recessed portion is recessed relative to the flat portion to form a first groove, and the flat portion is provided with a first surface and a second surface disposed opposite to each other, and the first surface faces the battery. The first groove is recessed from the first surface toward the second surface, and the bottom wall of the first groove is protruding relative to the second surface on the side away from the first surface. The auxiliary component is mounted on the second surface, and the portion of the bottom wall of the first groove protruding relative to the second surface is embedded in the auxiliary component.

[0037] In this embodiment, the auxiliary component is mounted on the second surface, and the portion of the bottom wall of the first groove that protrudes relative to the second surface is embedded in the auxiliary component. In this embodiment, the structure of the first recessed portion protruding relative to the flat portion is embedded in the auxiliary component, and the auxiliary component absorbs the structure of the first recessed portion protruding relative to the flat portion, so that the display screen can be installed flatly relative to the middle frame.

[0038] It is understandable that the side of the auxiliary member facing away from the second surface is a flat surface, so that the display screen can be installed flatly on the auxiliary member. Exemplarily, when the auxiliary member is a heat sink, the side of the auxiliary member facing away from the second surface is a flat surface, so that the display screen is fully in contact with the auxiliary member, thereby improving the heat dissipation effect of the auxiliary member on the display screen.

[0039] Exemplarily, the auxiliary component may be, but is not limited to, a heat sink. The heat sink is used to dissipate heat for the display screen to improve the reliability of the electronic device.

[0040] In a possible implementation, the first recessed portion is recessed relative to the flat portion to form a second recessed portion, and the opening of the second recessed portion is in the same direction as the opening of the first recessed portion; wherein the first recessed portion is located in the second recessed portion, and the depth of the first recessed portion is greater than the depth of the second recessed portion. The electronic device further includes a circuit board and an adhesive layer, the adhesive layer is connected between the circuit board and the recessed portion, the adhesive layer is accommodated in the first recessed portion, and a portion of the circuit board structure is accommodated in the second recessed portion.

[0041] In this embodiment, the depth of the first groove is greater than the depth of the second groove, so that the adhesive layer is accommodated in the first groove and part of the structure of the circuit board is accommodated in the second groove. The thickness of the adhesive layer and the circuit board is reused with the thickness of the middle frame, thereby reducing the overall thickness of the electronic device. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to illustrate the technical solutions in the embodiments of the present application or the background technology, the drawings required for use in the embodiments of the present application or the background technology will be described below.

[0043] Figure 1 is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application;

[0044] Figure 2 is Figure 1 a partial exploded structural schematic diagram of the electronic device shown;

[0045] Figure 3 is Figure 2 a structural schematic diagram of the middle frame shown;

[0046] Figure 4 is Figure 3 a top view of the middle frame shown;

[0047] Figure 5 is Figure 4 a cross-sectional schematic diagram of the middle frame shown along line A-A in the first embodiment;

[0048] Figure 6 is Figure 4 an enlarged structural schematic diagram of part a shown;

[0049] Figure 7 is Figure 3 a structural schematic diagram of the middle frame shown from another angle;

[0050] Figure 8 is Figure 1 a structural schematic diagram of the middle frame shown in the second embodiment;

[0051] Figure 9 is Figure 8 a cross-sectional schematic diagram of the middle frame shown along line B-B;

[0052] Figure 10 is Figure 1 a structural schematic diagram of the middle frame shown in the third embodiment;

[0053] Figure 11 is Figure 1 a structural schematic diagram of the middle frame shown in the fourth embodiment;

[0054] Figure 12 is Figure 11 a cross-sectional schematic diagram of the middle frame shown along line C-C;

[0055] Figure 13 is a partial cross-sectional schematic diagram of the electronic device provided in the embodiments of the present application in another embodiment. Detailed implementation manners

[0056] The embodiments of the present application will be described below with reference to the accompanying drawings in the embodiments of the present application.

[0057] Please refer to Figure 1 , Figure 1It is a schematic structural diagram of the electronic device 100 provided by an embodiment of the present application. The electronic device 100 can be products such as mobile phones, tablet computers, laptop computers, in-vehicle devices, wearable devices, etc., and the present application does not limit this. Among them, the wearable device can be a smart bracelet, a smart watch, augmented reality (AR) glasses, virtual reality (VR) glasses, etc. In the embodiment of the present application, the electronic device 100 is taken as a mobile phone for description.

[0058] As Figure 1 shown, the electronic device 100 includes a housing 101 and a battery 102, a main board 103, a sub-board 104, and a circuit board 105 located inside the housing 101. The battery 102 is used to provide power for each component inside the electronic device 100. The main board 103 (motherboard, Mobo), also known as the main board, system board, logic board, motherboard, or baseboard, etc., is the central or main circuit board that constitutes a complex electronic system such as the electronic device 100. The main board 103 integrates the operation management of the electronic device 100. The main board 103 is connected to the sub-board 104 and external accessories, and the external accessories can be, but are not limited to, a memory card, a subscriber identity module (SIM) card, or a charging interface, etc. The battery 102 is located between the main board 103 and the sub-board 104. The main board 103 and the sub-board 104 are respectively located at both ends of the battery 102. The circuit board 105 is electrically connected between the main board 103 and the sub-board 104, and the circuit board 105 extends from one end of the battery 102 to the other end of the battery 102. The circuit board 105 can be, but is not limited to, a flexible circuit board. Among them, Figure 1 the shapes, sizes, or positions of the battery 102, the main board 103, the sub-board 104, or the circuit board 105 shown in

[0059] are only examples, and the present application does not limit them.

[0060] Please refer to Figure 1 and Figure 2 , Figure 2 is Figure 1Exploded partial structural schematic diagram of the electronic device 100 shown. The electronic device 100 further includes a display screen 107. The display screen 107 is used to display images. The display screen 107 can be a flat screen or a curved screen, and the present application does not limit this. The housing 101 includes a middle frame 10 and a rear cover 20 mounted on the middle frame 10. The middle frame 10 provides a bearing function, for example, bearing one or more of the main board 103, the secondary board 104, the circuit board 105, the display screen 107, or the battery 102. Exemplarily, the display screen 107 and the battery 102 are respectively located on two opposite sides of the middle frame 10. The shapes of the middle frame 10 and the rear cover 20 in the figure are only examples, and the present application does not limit this.

[0061] As Figure 2 shown, the electronic device 100 further includes an adhesive layer 108. The adhesive layer 108 is used to fix the circuit board 105 and the connector 106 to the middle frame 10. In this embodiment, the circuit board 105 and the connector 106 are directly fixed to the middle frame 10 through the adhesive layer 108, which facilitates the assembly of the electronic device 100. The present application does not limit the material used for the adhesive layer 108, and those skilled in the art can design this according to actual requirements. For example, the adhesive layer 108 can be double-sided tape.

[0062] In some embodiments, the battery 102, the circuit board 105, the connector 106, the main board 103, and the secondary board 104 are located on the same side of the middle frame 10. The rear cover 20 is located on the side of the battery 102 facing away from the display screen 107. The rear cover 20 is fixed to the middle frame 10 to protect structures such as the circuit board 105 and the battery 102 carried on the middle frame 10. The present application does not limit the shape or material of the rear cover 20, etc., and those skilled in the art can design this according to actual requirements.

[0063] In some embodiments, the circuit board 105 and the connector 106 are arranged in a staggered manner, avoiding the stacking of the circuit board 105 and the connector 106, which is beneficial to reducing the thickness of the electronic device 100. Exemplarily, the connector 106 is located at the end of the battery 102 to electrically connect the battery 102 to the components inside the electronic device 100. The circuit board 105 extends from one end of the battery 102 to the other end of the battery 102 to connect the main board 103 and the secondary board 104.

[0064] Please continue to refer to Figure 1 and Figure 2, the middle frame 10 includes a first plate 11, a second plate 12, and a third plate 13 that are connected in sequence. The first plate 11, the second plate 12, and the third plate 13 are used to carry different components. Exemplarily, the first plate 11 is used to carry the main board 103, the second plate 12 is used to carry the battery 102, and the third plate is used to carry the secondary board 104. The second plate 12 includes a first end and a second end that are disposed opposite to each other. The first end is connected to the first plate 11, and the second end is connected to the third plate 13. Exemplarily, the first plate 11, the second plate 12, and the third plate 13 are integrally formed.

[0065] Please refer to Figure 1 and Figure 3 , Figure 3 is Figure 2 the schematic structural diagram of the middle frame 10 shown. The second plate 12 includes a flat portion 121, a first recessed portion 122, and a second recessed portion 123 that are integrally formed. The first recessed portion 122 recesses relative to the flat portion 121 to form a first receiving space 110. The first recessed portion 122 recesses relative to the flat portion 121 to form a second receiving space 120. The first receiving space 110 and the second receiving space 120 can be grooves or through holes. In the embodiments of the present application, the first receiving space 110 and the second receiving space 120 are taken as grooves for description.

[0066] Among them, the part of the circuit board 105 located on the second plate 12 is received in the first receiving space 110 and is located below the battery 102. The part of the connecting member 106 located on the second plate 12 is received in the second receiving space 120 and is located below the battery 102. It can be understood that the part of the circuit board 105 located on the first plate 11 or the third plate 13 is offset from the battery 102 to be connected to the main board 103 or the secondary board 104. The part of the connecting member 106 located on the first plate 11 is offset from the battery 102 to be electrically connected to the corresponding components. The shape of the first receiving space 110 matches the shape of the circuit board 105, and the shape of the second receiving space 120 matches the shape of the connecting member 106. Those skilled in the art can design the shapes of the first receiving space 110 and the second receiving space 120 according to the shapes of the circuit board 105 and the connecting member 106 inside the electronic device 100.

[0067] In this embodiment, the second plate 12 is provided with a receiving space for receiving the circuit board 105 and the connecting member 106. The part of the circuit board 105 or the connecting member 106 located below the battery 102 is embedded in the second plate 12, and the thickness space of the second plate 12 is reused with that of the circuit board 105 or the connecting member 106, reducing the thickness of the electronic device 100.

[0068] Exemplarily, the adhesive layer 108 includes a first adhesive layer 81 and a second adhesive layer 82. The first adhesive layer 81 is adhered between the circuit board 105 and the middle frame 10, and the first adhesive layer 81 is received in the first receiving space 110. The second adhesive layer 82 is adhered between the connecting member 106 and the middle frame 10, and the second adhesive layer 82 is received in the second receiving space 120.

[0069] Please refer to Figure 4 and Figure 5 , Figure 4 is Figure 3 the top view of the middle frame 10 shown in the figure; Figure 5 is Figure 4 the cross-sectional schematic view of the middle frame 10 shown in the figure along the line A-A in the first embodiment. The first receiving space 110 includes a first groove 111 and a second groove 112. The opening directions of the first groove 111 and the second groove 112 are the same. The first groove 111 is located in the second groove 112, and the groove depth of the first groove 111 is greater than the groove depth of the second groove 112. It can be understood that a part of the structure of the first groove 111 further recesses towards the first surface relative to the second groove 112. The first groove 111 is used to receive the first adhesive layer 81, and the second groove 112 is used to receive the circuit board 105. As Figure 4 shown, the first groove 111 is located at a partial position of the second groove 112.

[0070] Exemplarily, the flat portion 121 includes a first surface 1211 and a second surface 1212 which are arranged opposite to each other. The first surface 1211 faces the battery 102. The openings of the first groove 111 and the second groove 112 are both the first surface 1211. The first groove 111 and the second groove 112 both recess from the first surface 1211 towards the side of the second surface 1212 and do not penetrate the second surface 1212.

[0071] In this embodiment, the outer surface of the first adhesive layer 81 is smaller than the outer surface of the circuit board 105. The first adhesive layer 81 is adhered to a partial area of the circuit board 105. On the premise of ensuring the adhesion between the circuit board 105 and the middle frame 10, the space occupied by the first adhesive layer 81 is reduced, which is beneficial to the miniaturization of the electronic device 100.

[0072] In some embodiments, the second receiving space 120 includes a third groove 113 and a fourth groove 114. The opening directions of the third groove 113 and the fourth groove 114 are the same. The fourth groove 114 is located in the third groove 113, and the groove depth of the fourth groove 114 is greater than the groove depth of the third groove 113. It can be understood that a part of the structure of the fourth groove 114 further recesses towards the first surface 1211 relative to the third groove 113. The fourth groove 114 is used to receive the second adhesive layer 82, and the third groove 113 is used to receive the connecting member 106. As Figure 4As shown, the fourth groove 114 is located at a partial position of the third groove 113. In this embodiment, the second plate 12 is also correspondingly provided with a groove for accommodating the connecting member 106 and the second adhesive layer 82, which reduces the thickness of the electronic device 100 as a whole.

[0073] Please refer to Figure 2 and Figure 4 , the first adhesive layer 81 includes a plurality of sub-adhesive layers 108 arranged at intervals. The number of the first grooves 111 is multiple, and the multiple first grooves 111 are arranged at intervals and are all located in the second groove 112. The plurality of sub-adhesive layers 108 are respectively accommodated in the plurality of first grooves 111 to bond different positions of the circuit board 105, improving the stability of the bonding between the circuit board 105 and the middle frame 10. Among them, the shapes of the plurality of first grooves 111 may be the same or different, and the present application does not limit this. The number of the first grooves 111 is also not limited in the present application, and the number in the figure is only an example.

[0074] Among them, the flat portion 121, the first concave portion 122 and the second concave portion 123 are prepared by a die-casting process. The die-casting process is a casting method in which molten material is filled into the die cavity at high speed under the action of high pressure and the material solidifies under pressure to form a die-cast part. In this embodiment, the flat portion 121, the first concave portion 122 and the second concave portion 123 are prepared by the die-casting process, which not only reduces the cost of the middle frame 10, but also improves the forming efficiency of the middle frame 10.

[0075] In this embodiment, the first groove 111 is located in the second groove 112, and the groove depth of the first groove 111 is greater than the groove depth of the second groove 112. During the die-casting process of the middle frame 10, in the material flow direction, the cavity structure corresponding to the groove wall of the second groove 112 forms a first flow resistance to the material flow, and the cavity structure corresponding to the groove wall of the first groove 111 forms another flow resistance to the material flow, affecting the thickness of the flat portion 121 integrally formed with the first concave portion 122 and the second concave portion 123, and finally affecting the thickness of the middle frame 10.

[0076] In the traditional technology, the bottom wall of the first groove is rectangular, and the material flow direction is perpendicular to the side of the rectangle. During the die-casting process of the middle frame, the cavity structure corresponding to the groove wall of the first groove has a strong flow resistance to the material, and cold material defects are likely to occur at the slag discharge side rib position, resulting in a thicker thickness of the formed middle frame. For example, the thicknesses of the first concave portion, the second concave portion and the flat portion are thicker, which is not conducive to the overall thinning of the middle frame.

[0077] In this application, by changing the shape of the first recess 122 in the middle frame 10, the flow resistance of the material by the cavity structure corresponding to the first recess 122 is reduced, the risk of cold material generation at the slag discharge side rib position is minimized, and the thickness of the formed first recess 122, second recess 123, and flat portion 121 is avoided from being too thick, thereby facilitating the overall thinning of the middle frame 10.

[0078] Please refer to Figure 6 , Figure 6 is Figure 4 an enlarged schematic structural view of part a shown in the figure. The first recess 122 includes a bottom wall 1220, a first side wall 1221, and a second side wall 1222. The orientation of the bottom wall 1220 is the same as that of the first surface 1211. The first side wall 1221 and the second side wall 1222 intersect with the bottom wall 1220 respectively. The first side wall 1221 and the second side wall 1222 are connected and intersect. Exemplarily, the shape of the bottom wall 1220 is quadrilateral. The groove wall of the first groove 111 further includes a third side wall 1223 and a fourth side wall 1224 that are connected and intersect. The third side wall 1223 is connected between the second side wall 1222 and the fourth side wall 1224, and the fourth side wall 1224 is between the first side wall 1221 and the third side wall 1223. The first side wall 1221, the second side wall 1222, the third side wall 1223, the fourth side wall 1224, and the bottom wall 1220 together enclose and form the first groove 111. It can be understood that the first side wall 1221, the second side wall 1222, the third side wall 1223, the fourth side wall 1224, and the bottom wall 1220 are all groove walls of the first groove 111.

[0079] As Figure 4 shown, in the first direction X, the opening formed by the first side wall 1221 and the second side wall 1222 gradually becomes larger. Among them, during the die-casting process of the middle frame 10, the first direction X is parallel to the flow direction of the die-casting material. Exemplarily, the first direction X is the shortest direction for the filling material to flow along the middle frame 10. In this embodiment, taking the first direction X as the width direction of the middle frame 10 as an example for description. It can be understood that the first direction X is the short side direction of the middle frame 10. In other embodiments, the first direction X can also be other directions of the middle frame 10, and this application does not limit this.

[0080] In this embodiment, in the first direction X, the opening formed by the first side wall 1221 and the second side wall 1222 gradually becomes larger, and the direction of the opening is parallel to the material flowing during the die-casting process of the middle frame 10. The material gradually disperses along the cavities corresponding to the first side wall 1221 and the second side wall 1222, reducing the flow resistance of the cavity side walls corresponding to the first side wall 1221 and the second side wall 1222 to the material, minimizing the risk of cold material generation at the slag discharge side rib position, and avoiding the thickness of the first recess 122, second recess 123, and flat portion 121 in the middle frame 10 from being too thick, thereby facilitating the overall thinning of the middle frame 10.

[0081] Among them, the thickness of the flattening part 121 is thinned, and correspondingly, the thicknesses of the first recessed part 122 and the second recessed part 123 are also thinned. The thinned thickness of the flattening part 121 can be different from the thinned thickness of the first recessed part 122 or the second recessed part 123. Exemplarily, in the first direction X, the opening formed by the first side wall 1221 and the second side wall 1222 gradually becomes larger, which can reduce the thickness of the flattening part 121 by more than 0.05 mm, and reduce the thickness of the first recessed part 122 or the second recessed part 123 by more than 0.03 mm.

[0082] Among them, in the direction of the material flow, the smaller the angle formed by the first side wall 1221 and the second side wall 1222, the smaller the angle formed by the first side wall 1221 or the second side wall 1222 and the material flow direction, and the smaller the flow resistance of the first side wall 1221 or the second side wall 1222 to the material. It can be understood that when the first side wall 1221 or the second side wall 1222 is perpendicular to the material flow direction, and the first side wall 1221 or the second side wall 1222 forms an acute angle with the material flow direction, part of the structure of the first side wall 1221 or the second side wall 1222 deviates from the material flow direction, resulting in a large flow resistance of the first side wall 1221 or the second side wall 1222 to the material.

[0083] In some embodiments, the angle formed by the first side wall 1221 and the second side wall 1222 is an acute angle. The present application does not limit the specific angle formed by the first side wall 1221 and the second side wall 1222. Exemplarily, the angle formed by the first side wall 1221 and the second side wall 1222 is less than or equal to 80 degrees.

[0084] In the embodiment of the present application, the angle formed by the first side wall 1221 and the second side wall 1222 is an acute angle, and the angle formed by the first side wall 1221 and the second side wall 1222 is small. During the die-casting process of the middle frame 10, the flow resistance of the first side wall 1221 and the second side wall 1222 to the material is small, further reducing the flow resistance of the groove wall of the first groove 111 to the material, which is more conducive to thinning the thicknesses of the first recessed part 122, the second recessed part 123 and the flattening part 121.

[0085] In some embodiments, the area of the bottom wall 1220 is relatively large, which increases the bonding area between the middle frame 10 and the circuit board 105, thereby ensuring the stability of the bonding layer 108 for bonding the circuit board 105 and the middle frame 10. Exemplarily, the angle formed by the first side wall 1221 and the second side wall 1222 is greater than or equal to 15 degrees, preventing the area of the bottom wall 1220 from being small due to the small angle formed by the first side wall 1221 and the second side wall 1222. It can be understood that the angle formed by the first side wall 1221 and the second side wall 1222 should not be too small or too large. The present application does not limit the specific angle of the acute angle formed by the first side wall 1221 and the second side wall 1222, and those skilled in the art can design it according to actual requirements.

[0086] In some embodiments, the length of the first side wall 1221 is equal to the length of the second side wall 1222. The first side wall 1221 and the second side wall 1222 are symmetrically arranged. In this embodiment, since the first side wall 1221 and the second side wall 1222 are symmetrically arranged, they have the same flow resistance to the material, which is beneficial to the uniform thickness distribution of the side structures of the first side wall 1221 and the second side wall 1222.

[0087] Exemplarily, the shapes of the first side wall 1221, the second side wall 1222, the third side wall 1223, and the fourth side wall 1224 are the same. In this embodiment, the shape of the bottom wall 1220 is described as a rhombus. In other embodiments, the length of the first side wall 1221 and the length of the third side wall 1223, or the length of the second side wall 1222 and the length of the fourth side wall 1224 may also be different, and the present application does not limit this.

[0088] Please continue to refer to Figure 4 and Figure 5 , in some embodiments, the shape of the fourth groove 114 is the same as the shape of the first groove 111, and in the first direction X, the openings formed by two adjacent side walls of the fourth groove 114 gradually become larger. Exemplarily, the bottom walls 1220 of both the fourth groove 114 and the first groove 111 are in the shape of a rhombus. The groove depth of the fourth groove 114 is the same as the groove depth of the first groove 111, and the groove depth of the third groove 113 is the same as the groove depth of the second groove 112.

[0089] In this embodiment, since the shape of the fourth groove 114 is the same as the shape of the first groove 111 and the openings formed by two adjacent side walls of the fourth groove 114 gradually become larger, during the die-casting process of the middle frame 10, not only the flow resistance of the cavity structure corresponding to the first recess 122 to the material is reduced, but also the flow resistance of the cavity structure corresponding to the second recess 123 to the material is reduced. Further, the risk of cold material generation in the slag discharge side rib position is reduced, which is more beneficial to the thinning of the first recess 122, the second recess 123, and the flat portion 121.

[0090] In other embodiments, the shape of the fourth groove 114 may also be different from the shape of the first groove 111, and the present application does not limit this. For example, the bottom wall 1220 of the first groove 111 is diamond-shaped, and the bottom wall 1220 of the fourth groove 114 is rectangular.

[0091] Please refer to Figure 5 and Figure 7 , Figure 7 is Figure 3 a schematic structural diagram of the middle frame 10 shown in another angle. Figure 7 is Figure 4 a schematic structural diagram of the middle frame 10 shown after being flipped 180 degrees in another angle.

[0092] In this embodiment, the side of the bottom wall 1220 of the first groove 111 facing away from the first surface 1211 is flush with the second surface 1212, and the side of the bottom wall 1220 of the fourth groove 114 facing away from the first surface 1211 is flush with the second surface 1212. Among them, the shapes of the first groove 111 and the fourth groove 114 cannot be observed in the top view of the middle frame 10 along the angle of the second surface 1212. Figure 7 The structures of the first groove 111 and the fourth groove 114 are marked with dotted lines in

[0093] to indicate the approximate positions of the first groove 111 and the fourth groove 114. In this embodiment, both opposite sides of the flat portion 121 are planar. Figure 8 and Figure 9 , Figure 8 is Figure 1 a schematic structural diagram of the middle frame 10 in the second embodiment shown; Figure 9 is Figure 8 a schematic cross-sectional diagram of the middle frame 10 along the line B-B shown. The middle frame 10 in this embodiment includes most of the technical features of the first embodiment, and the following content of most of the technical solutions that are the same as those of the first embodiment will not be repeated. For example, the middle frame 10 includes an integrally formed flat portion 121 and a first recessed portion 122. The first recessed portion 122 is recessed inward relative to the first surface 1211 of the flat portion 121 to form the first groove 111. Among them, in the first direction X, the opening formed by the adjacent first side wall 1221 and the second side wall 1222 of the first groove 111 gradually becomes larger.

[0094] In this embodiment, the third groove 113 is staggered from the second groove 112, and in the second direction Y, the fourth groove 114 is staggered from the first groove 111. The second direction Y is perpendicular to the first direction X. Exemplarily, the second direction Y is the length direction of the middle frame 10. It can be understood that the fourth groove 114 and the first groove 111 are staggered in both the first direction X and the second direction Y. The third groove 113 and the second groove 112 are only staggered in the first direction X. As Figure 9 shown, in the cross-sectional view of the middle frame 10 along the line parallel to the first direction X, only the third groove 113, the second groove 112, and the first groove 111 are shown, and the fourth groove 114 is not shown.

[0095] In this embodiment, the fourth groove 114 and the first groove 111 are staggered in both the first direction X and the second direction Y, reducing the overlapping area of the fourth groove 114 and the first groove 111, avoiding the double or multiple blockages of the material flow by the mold cavities in the same direction during the molding process of the middle frame 10, reducing the cold material risk of the slag discharge side ribs of the mold cavity to the material, and thus further reducing the thickness of the first recessed portion 122, the second recessed portion 123, and the flat portion 121.

[0096] Please refer to Figure 10 , Figure 10 which Figure 1 is a schematic structural view of the middle frame 10 in the third embodiment. The middle frame 10 in this embodiment includes most of the technical features of the foregoing embodiment, and most of the same technical solution contents in this embodiment and the foregoing embodiment will not be described in detail hereinafter. For example, the middle frame 10 includes an integrally formed flat portion 121 and a first recessed portion 122. The first recessed portion 122 is recessed inward relative to the first surface 1211 of the flat portion 121 to form the first groove 111. Among them, in the first direction X, the opening formed by the first side wall 1221 and the second side wall 1222 adjacent to the first groove 111 gradually becomes larger.

[0097] In this embodiment, the bottom wall 1220 of the first groove 111 is triangular. The side walls of the first groove 111 include a first side wall 1221, a second side wall 1222, and a third side wall 1223. The first side wall 1221, the second side wall 1222, and the third side wall 1223 are connected to each other and are connected to the bottom wall 1220. Exemplarily, the angle formed by the first side wall 1221 and the second side wall 1222 is 60 degrees, and the bottom wall 1220 is an equilateral triangle.

[0098] It is understandable that in the first direction X, when the opening formed by the first side wall 1221 and the second side wall 1222 gradually becomes larger, the present application exemplifies that the shape of the bottom wall 1220 can be a triangle or a parallelogram. In other embodiments, the bottom wall 1220 can also be in other shapes, such as a pentagon or a hexagon, etc., and the present application does not limit this.

[0099] See also Figure 11 and Figure 12 , Figure 11 yes Figure 1 The structure diagram of the middle frame 10 in the fourth embodiment is shown; Figure 12 yes Figure 11 The middle frame 10 is shown as a cross-sectional schematic diagram along the CC line. The middle frame 10 in this embodiment includes most of the technical features of the aforementioned embodiments, and most of the technical solutions of this embodiment that are the same as those of the aforementioned embodiments are not repeated here. For example, the middle frame 10 includes an integrally formed flat portion 121 and a first recessed portion 122, and the first recessed portion 122 is recessed inward relative to the first surface 1211 of the flat portion 121 to form a first groove 111. Among them, in the first direction X, the opening formed by the first side wall 1221 and the second side wall 1222 adjacent to the first groove 111 gradually becomes larger.

[0100] In this embodiment, the first groove 111 is recessed from the first surface 1211 toward the second surface 1212, and the side of the bottom wall 1220 of the first groove 111 away from the first surface 1211 is protruding relative to the second surface 1212. Figure 11 As shown, the shapes of the first groove 111 and the fourth groove 114 can be observed from the top view of the middle frame 10 along the second surface 1212. It can be understood that when the groove depths of the first groove 111 are equal, when the side of the bottom wall 1220 of the first groove 111 away from the first surface 1211 is convex relative to the second surface 1212, the bottom wall 1220 of the first groove 111 is thicker.

[0101] In this embodiment, the side of the bottom wall 1220 of the first groove 111 that is away from the first surface 1211 is protruded relative to the second surface 1212, thereby increasing the thickness of the bottom wall 1220 of the first groove 111. During the molding process of the middle frame 10, the material has less resistance to flow along the mold cavity corresponding to the first groove 111, thereby reducing the risk of cold material being easily generated at the slag discharge side bone position, and avoiding the thickness of the flat portion 121 of the molded middle frame 10 being too thick, thereby facilitating reducing the thickness of the flat portion 121 in the middle frame 10.

[0102] In some embodiments, the height of the bottom wall 1220 of the first groove 111 protruding from the second surface 1212 is less than or equal to 0.2 mm. Exemplarily, the height of the bottom wall 1220 of the first groove 111 protruding from the second surface 1212 is 0.16 mm, 0.1 mm or 0.05 mm.

[0103] In this embodiment, the height by which the bottom wall 1220 of the first groove 111 protrudes relative to the second surface 1212 is small, and the thickness of the bottom wall 1220 of the first groove 111 is appropriately increased to avoid increasing the overall thickness of the middle frame 10 due to the relatively thick bottom wall 1220 of the first groove 111.

[0104] Please continue to refer to Figure 13 , Figure 13 FIG. is a partial cross-sectional schematic diagram of the electronic device 100 provided in an embodiment of the present application in another embodiment. The electronic device 100 in this embodiment includes most of the technical features of the foregoing embodiment, and most of the same technical solution contents in this embodiment and the foregoing embodiment will not be described in detail below. For example, the electronic device 100 includes a battery 102, a display screen 107, a middle frame 10, a main board, a secondary board, and a circuit board 105. The battery 102, the main board, and the secondary board are located on the same side of the middle frame 10 and are arranged staggeredly. The display screen 107 and the battery 102 are respectively installed on two opposite sides of the middle frame 10. The circuit board 105 is electrically connected between the main board and the secondary board. The middle frame 10 includes an integrally formed flat portion 121 and a first recessed portion 122. The first recessed portion 122 is recessed relative to the flat portion 121 to form a first groove 111. The flat portion 121 is provided with a first surface 1211 and a second surface 1212 that face away from each other. The first surface 1211 faces the battery 102, and the first groove 111 is recessed from the first surface 1211 toward the side of the second surface 1212.

[0105] In this embodiment, the side of the bottom wall 1220 of the first groove 111 facing away from the first surface 1211 protrudes relative to the second surface 1212. In this embodiment, the side of the bottom wall 1220 of the first groove 111 facing away from the first surface 1211 protrudes relative to the second surface 1212, which increases the thickness of the bottom wall 1220 of the first groove 111. During the molding process of the middle frame 10, the resistance of the material flowing along the cavity corresponding to the first groove 111 is small, reducing the risk of cold material easily generated at the slag discharge side rib position, and avoiding the relatively thick thickness of the flat portion 121 of the molded middle frame 10, thereby facilitating reducing the thickness of the flat portion 121 in the middle frame 10.

[0106] Among them, the electronic device 100 further includes an auxiliary member 109. The auxiliary member 109 is located between the middle frame 10 and the display screen 107. Exemplarily, the auxiliary member 109 is a heat sink. The heat sink is used to dissipate heat from the display screen 107 to improve the reliability of the electronic device 100. The present application does not limit the shape of the auxiliary member 109, and the shape of the auxiliary member 109 in the figure is only an example. The heat sink can be, but is not limited to, a graphite sheet. In other embodiments, the auxiliary member 109 can also be a foam or a mylar sheet, etc., and the present application does not limit this.

[0107] In this embodiment, the auxiliary member 109 is installed on the second surface 1212, and a portion of the bottom wall 1220 of the first groove 111 protruding relative to the second surface 1212 is embedded in the auxiliary member 109. In this embodiment, a structure in which the first recess 122 protrudes relative to the flat portion 121 is embedded in the auxiliary member 109, and the auxiliary member 109 absorbs the structure in which the first recess 122 protrudes relative to the flat portion 121, so that the display screen 107 can be installed flatly relative to the middle frame 10.

[0108] It can be understood that one side of the auxiliary member 109 facing away from the second surface 1212 is a flat surface, so that the display screen 107 can be installed flatly on the auxiliary member 109. Exemplarily, when the auxiliary member 109 is a heat sink, one side of the auxiliary member 109 facing away from the second surface 1212 is a flat surface, so that the display screen 107 is in full contact with the auxiliary member 109, improving the heat dissipation effect of the auxiliary member 109 on the display screen 107.

[0109] In some embodiments, a second groove 112 is further formed by the first recess 122 being recessed relative to the flat portion 121. The opening direction of the second groove 112 is the same as that of the first groove 111. Among them, the first groove 111 is located in the second groove 112, and the groove depth of the first groove 111 is greater than the groove depth of the second groove 112. The electronic device 100 further includes an adhesive layer 108, and the adhesive layer 108 is connected between the circuit board 105 and the recessed portion. The adhesive layer 108 is received in the first groove 111, and a partial structure of the circuit board 105 is received in the second groove 112.

[0110] In this embodiment, the groove depth of the first groove 111 is greater than that of the second groove 112, so that the adhesive layer 108 is received in the first groove 111, and a partial structure of the circuit board 105 is received in the second groove 112. The thicknesses of the adhesive layer 108 and the circuit board 105 are reused with the thickness of the middle frame 10, reducing the overall thickness of the electronic device 100.

[0111] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present application, and all of them should be covered by the protection scope of the present application; without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A middle frame, which is prepared by a die-casting process, characterized in that, The middle frame includes an integrally formed flat portion and a first recessed portion, wherein the first recessed portion is recessed inward relative to the first surface of the flat portion to form a first groove, and an opening of the first groove is located on the first surface; The first recessed portion includes a bottom wall, a first side wall and a second side wall, the orientation of the bottom wall is the same as that of the first surface, the first side wall and the second side wall respectively intersect with the bottom wall, and the first side wall is connected to the second side wall; in a first direction, the opening formed by the first side wall and the second side wall gradually becomes larger, and during the die-casting process of the middle frame, the first direction is parallel to the flow direction of the die-casting material.

2. The middle frame according to claim 1, characterized in that, An angle formed by the first side wall and the second side wall is an acute angle.

3. The middle frame according to claim 1, characterized in that, The shape of the bottom wall includes a quadrilateral or a triangle.

4. The middle frame according to any one of claims 1 to 3, characterized in that, The first recessed portion is recessed relative to the flat portion to form a second recessed portion, and the opening of the second recessed portion has the same opening direction as the first recessed portion; wherein the first recessed portion is located in the second recessed portion, and the depth of the first recessed portion is greater than the depth of the second recessed portion.

5. The middle frame according to claim 4, characterized in that The flattened portion is provided with a second surface disposed opposite to the first surface, the first groove is recessed from the first surface toward the second surface, and the side of the bottom wall away from the first surface is convex relative to the second surface.

6. The middle frame according to claim 5, characterized in that, The middle frame includes a first plate, a second plate and a third plate connected in sequence, and the first plate, the second plate and the third plate are used to carry different components; the second plate includes a first end and a second end arranged opposite to each other, the first end is connected to the first plate, the second end is connected to the third plate, and the second groove extends from the first end to the second end; wherein the number of the first grooves is multiple, the multiple first grooves are arranged at intervals, and are all located in the second groove.

7. The middle frame according to claim 6, characterized in that, The middle frame further includes a second recessed portion, the second recessed portion is integrally formed with the flat portion, and the second recessed portion is recessed relative to the flat portion to form a third recessed groove and a fourth recessed groove, the third recessed groove and the fourth recessed groove are both recessed from the first surface toward one side of the second surface, the fourth recessed groove is located in the third recessed groove, and the recessed depth of the fourth recessed groove is greater than the recessed depth of the third recessed groove; Along the first direction, the third groove is staggered with the second groove, and along the second direction, the fourth groove is staggered with the first groove; wherein the second direction is perpendicular to the first direction.

8. The middle frame according to claim 7, wherein The shape of the fourth groove is the same as that of the first groove, and in the first direction, an opening formed by two adjacent side walls of the fourth groove gradually becomes larger.

9. The middle frame according to any one of claims 1 to 3, characterized in that The flattened portion is provided with a second surface disposed opposite to the first surface, the first groove is recessed from the first surface toward the second surface, and the side of the bottom wall away from the first surface is convex relative to the second surface.

10. An electronic device, characterized in that, The invention comprises a battery and a middle frame as claimed in any one of claims 1 to 9, wherein the battery is installed on the middle frame.

11. The electronic device according to claim 10, characterized in that, The electronic device also includes a circuit board and an adhesive layer, the projection of the circuit board on the middle frame at least partially overlaps with the first recessed portion, the adhesive layer is connected between the circuit board and the first recessed portion, and the adhesive layer is accommodated in the first groove.

12. An electronic device, characterized in that, It includes a battery, a display screen, a middle frame and an auxiliary component, wherein the battery and the display screen are both installed on the middle frame, and the battery and the display screen are respectively located on two sides of the middle frame that are arranged opposite to each other, and the auxiliary component is located between the middle frame and the display screen; The middle frame includes an integrally formed flat portion and a first recessed portion, the first recessed portion is recessed relative to the flat portion to form a first groove, the flat portion is provided with a first surface and a second surface disposed opposite to each other, the first surface faces the battery, the first groove is recessed from the first surface toward the second surface, and the bottom wall of the first groove is protruded relative to the second surface on the side away from the first surface; wherein the auxiliary component is mounted on the second surface, and the portion of the bottom wall of the first groove protruding relative to the second surface is embedded in the auxiliary component; The first recessed portion includes a bottom wall, a first side wall and a second side wall, the orientation of the bottom wall is the same as that of the first surface, the first side wall and the second side wall respectively intersect with the bottom wall, and the first side wall is connected to the second side wall; in a first direction, the opening formed by the first side wall and the second side wall gradually becomes larger, and during the die-casting process of the middle frame, the first direction is parallel to the flow direction of the die-casting material.

13. The electronic device according to claim 12, wherein The first recessed portion is recessed relative to the flat portion to form a second recessed portion, and the opening of the second recessed portion is in the same direction as the opening of the first recessed portion; wherein the first recessed portion is located in the second recessed portion, and the depth of the first recessed portion is greater than the depth of the second recessed portion; The electronic device further includes a circuit board and an adhesive layer, wherein the adhesive layer is connected between the circuit board and the recessed portion, the adhesive layer is received in the first groove, and a part of the structure of the circuit board is received in the second groove.

Images