Vapor chamber, electronic device, and manufacturing method for vapor chamber

Abstract

The present application provides a vapor chamber, an electronic device, and a manufacturing method for a vapor chamber, for use in solving the problems of a complicated production process and a low yield of existing vapor chambers having a step difference. During laser welding of the vapor chamber provided in the present application, a laser welding head is suspended above a second cover plate, and a laser beam emitted from the laser welding head is perpendicular to the surface of a third portion of the second cover plate facing away from a first cover plate. By controlling the laser welding head to move in a plane, a laser spot moves along an edge area of the third portion on the second cover plate around an accommodating cavity formed by the communication of a first recessed portion and a second recessed portion, so as to weld a first portion of the first cover plate and the third portion of the second cover plate together, thereby completing edge sealing of a housing. In the described welding process, one-time welding can be achieved without adjusting welding parameters (for example, welding focal length, laser power, etc.), thus improving welding efficiency and the yield and stability of the vapor chamber.

Description

Heat spreader, electronic equipment, and manufacturing method of heat spreader

[0001] This application claims priority to Chinese Patent Application No. 202411922172.4, filed with the State Intellectual Property Office of China on December 23, 2024, entitled "Evaporator, Electronic Device and Method for Manufacturing Evaporator", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of electronic equipment technology, and in particular to a vapor chamber, an electronic device, and a method for manufacturing the vapor chamber. Background Technology

[0003] With the continuous development of electronic devices (such as mobile phones and tablets), the heat generated by some components inside these devices is also increasing. Therefore, heat spreaders are installed inside electronic devices to dissipate heat from components that generate a lot of heat.

[0004] As the density of components inside electronic devices increases and the size of some components grows, the vapor chamber may interfere with some components along the thickness direction of the electronic device. Therefore, in some cases, it is necessary to design stepped sections on the vapor chamber (i.e., the vapor chamber consists of multiple sections that are not on the same plane) to avoid interference with other components. However, existing vapor chambers with stepped sections have a relatively complicated manufacturing process and a low yield rate. Summary of the Invention

[0005] This application provides a vapor chamber, an electronic device, and a method for manufacturing a vapor chamber, which solves the problems of cumbersome manufacturing process and low yield of existing vapor chambers with stepped differences.

[0006] To achieve the above objectives, the embodiments of this application adopt the following technical solutions:

[0007] In a first aspect, embodiments of this application provide a temperature distribution plate, which includes a shell and a liquid absorption core.

[0008] The housing includes a first cover plate and a second cover plate disposed opposite to each other. The first cover plate has a first surface adjacent to the second cover plate and includes a first portion and a second portion. The first portion extends around the second portion, the thickness of the second portion is greater than the thickness of the first portion, and the first and second portions are flush with the first surface. A first recess is provided on the side of the second portion adjacent to the second cover plate. The second cover plate has a second surface adjacent to the first cover plate and includes a third portion and a fourth portion. The third portion extends around the fourth portion, the thickness of the fourth portion is greater than the thickness of the third portion, and the third and fourth portions are flush with the second surface. A second recess is provided on the side of the fourth portion adjacent to the first cover plate. In the thickness direction of the heat spreader, a portion of the second portion overlaps with a portion of the fourth portion, and the first and second recesses communicate to form a receiving cavity. A liquid-absorbing core is disposed within the receiving cavity.

[0009] The heat spreader provided in the first aspect of this application, through the aforementioned structural design of the first and second cover plates, can also form a stepped structure on the heat spreader. During manufacturing, simply fix the first and second cover plates onto a fixture, ensuring the first and second surfaces are in contact. Taking the second cover plate clamped above the first cover plate as an example, during laser welding, the laser welding head is suspended above the second cover plate, and the emitted laser beam is perpendicular to the third portion of the second cover plate, away from the surface of the first cover plate. By controlling the movement of the laser welding head, the laser spot moves around the accommodating cavity formed by the connection of the second and first recesses along the edge area of ​​the third portion on the second cover plate, thus welding the third portion of the second cover plate and the first portion of the first cover plate together, completing the edge sealing of the shell. During the welding process, the distance between the laser welding head and the surface of the third portion away from the first cover plate remains constant. Therefore, it is possible to achieve one-time welding without adjusting welding parameters (such as laser power, welding focal length, laser welding head moving speed, etc.), thereby improving welding efficiency, as well as the yield and stability of the heat spreader.

[0010] In conjunction with the first aspect, in one possible implementation, the absorbent core is attached to the second cover plate. The absorbent core includes a first region and a second region connected together. The first region is at least partially located within a second recess, and the second region is at least partially located within the first recess. The following examples will use the first region of the absorbent core as the evaporation region and the second region as its condensation region. In use, the fourth portion of the second cover plate is attached to the heating element, and the first cover plate is attached to the middle plate of the electronic device (the middle plate has a clearance groove for avoiding the second portion of the first cover plate). A heat dissipation channel is formed between the sidewall of the absorbent core and the inner wall of the accommodating cavity. The heat generated by the heating element is conducted through the fourth portion of the second cover plate to the first region of the absorbent core. The liquid working fluid in the first region rapidly vaporizes to form steam. Driven by thermal diffusion, this steam flows through the heat dissipation channel to the second region, where it condenses into liquid and releases heat. The heat is conducted through the second portion of the first cover plate to the middle frame and then diffuses into the external environment. The liquid entering the second region flows back to the first region through the capillary action of the wick, and this cycle can achieve heat dissipation and cooling of the heating element.

[0011] In conjunction with the first aspect, in another possible implementation, a first groove is provided on the side of the third part near the second part. The first groove communicates with the second recess, and the second region of the absorbent core is located within the first groove. This effectively embeds a portion of the second region of the absorbent core into the third part of the second cover plate, thereby reducing the depth of the first recess for accommodating the second region and consequently reducing the thickness of the second part of the first cover plate. This reduces the overall thickness of the vapor chamber, contributing to the thinner and lighter design of electronic devices. Furthermore, by creating the first groove, the material thickness of the second cover plate at the bottom of the first groove is reduced, allowing the heat released during vapor condensation to be conducted to the surrounding environment more quickly through the second cover plate, thus improving the heat dissipation efficiency of the vapor chamber.

[0012] In conjunction with the first aspect, in another possible implementation, a second groove is provided on the side of the first part near the fourth part, and the second groove communicates with the first recess. In this way, when the absorbent core is also in contact with the first cover plate, the first area of ​​the absorbent core can be partially located in the second groove, which is equivalent to embedding a part of the first area of ​​the absorbent core into the first part of the first cover plate. This reduces the depth of the second recess used to accommodate the first area, and the thickness of the fourth part of the second cover plate is also reduced accordingly. This reduces the overall thickness of the heat spreader, which is beneficial for the thinning and lightening of electronic devices.

[0013] In conjunction with the first aspect, in another possible implementation, the vapor chamber also includes a support structure supported between the wick and the first cover plate. In this way, when the wick is not in contact with the first cover plate (i.e., the thickness of the wick is less than the depth of the first and second recesses), the support structure can compress the wick, ensuring it adheres tightly to the second cover plate and guaranteeing efficient heat transfer between them. Furthermore, the support structure can also work with the wick to support the vapor chamber shell, preventing partial collapse of the shell when subjected to pressure or impact. Additionally, the support structure separates the wick from the first cover plate, allowing a portion of the space between them to serve as a heat dissipation channel. This enables the vapor generated in the first region to flow quickly to the second region, improving the evaporation and condensation cycle efficiency of the liquid working fluid and thus enhancing the vapor chamber's heat dissipation efficiency.

[0014] In conjunction with the first aspect, in another possible implementation, the support structure includes multiple support columns spaced apart, with one end of each support column abutting against the first cover plate and the other end of each support column abutting against the liquid-absorbing core.

[0015] In conjunction with the first aspect, in another possible implementation, a portion of the first cover plate protrudes towards the second cover plate to form a support structure. That is, the support structure is integrally formed with the first cover plate, for example, through processes such as stamping, casting, machining, or 3D printing.

[0016] In conjunction with the first aspect, in another possible implementation, the heat spreader also includes a fastener connected to the outside of the housing, which is used to mount and secure the heat spreader. This facilitates the mounting and securing of the heat spreader within the electronic device and ensures a tight fit between the heat spreader and the heating element and the middle plate.

[0017] In conjunction with the first aspect, in another possible implementation, the fastener has mounting holes that penetrate the fastener along the thickness direction of the heat spreader. For example, the heat spreader can be fixed to the middle plate by screws, rivets, clips, etc., inserted into the mounting holes.

[0018] In conjunction with the first aspect, in another possible implementation, the vapor chamber also includes a liquid working fluid, which is filled within the wick. The liquid working fluid undergoes evaporation and condensation circulation within the vapor chamber, thereby dissipating heat from the heating element. For example, the liquid working fluid can be deionized water, refrigerant, etc.

[0019] Secondly, this application provides an electronic device comprising:

[0020] The housing, the heating element, and the heat spreader provided in the first aspect of this application are provided, wherein the heating element and the heat spreader are both disposed inside the housing, and the heating element is attached to the heat spreader.

[0021] It is understood that the beneficial effects that the electronic device described in the second aspect and any possible implementation thereof can be referred to as the beneficial effects in the first aspect and any possible implementation thereof, and will not be repeated here.

[0022] Thirdly, this application provides a method for manufacturing a heat exchanger, the method comprising the following steps:

[0023] The first cover plate is stamped to form a first recess on the first cover plate; wherein the first cover plate includes a first part and a second part, the first part extends around the second part, and the first recess is formed by stamping the second part;

[0024] The second cover plate is stamped to form a second recess on the second cover plate; wherein the second cover plate includes a third part and a fourth part, the third part extends around the fourth part, and the second recess is formed by stamping the fourth part;

[0025] The absorbent core is attached to the second cover plate;

[0026] The first cover plate and the second cover plate are fastened together; wherein, after fastening, a portion of the first recess and a portion of the second recess overlap in the thickness direction of the first portion;

[0027] The first and third parts are welded together using laser welding to obtain a heat spreader.

[0028] In conjunction with the third aspect, in one possible implementation, the method further includes, before attaching the absorbent core to the second cover plate:

[0029] An injection hole is made on the first or second cover plate.

[0030] In conjunction with the third aspect, in another possible implementation, after welding the first and third parts together using laser welding, the method further includes:

[0031] Liquid working fluid is injected into the first or second recess through the injection hole;

[0032] Seal the injection hole.

[0033] In conjunction with the third aspect, in another possible implementation, the above method further includes, before the first cover plate and the second cover plate are fastened together:

[0034] Multiple support columns are provided on the side of the suction core away from the second cover plate, and the multiple support columns are distributed at intervals.

[0035] Understandably, the beneficial effects that can be achieved by the method of manufacturing the heat spreader described in the third aspect and any possible implementation thereof can be referred to as the beneficial effects in the first aspect and any possible implementation thereof, and will not be repeated here. Attached Figure Description

[0036] Figure 1 is a structural diagram of the electronic device provided in an embodiment of this application;

[0037] Figure 2 is an exploded view of the electronic device in Figure 1 above;

[0038] Figure 3 is a schematic diagram of the connection between a heat spreader and a heating element provided in an embodiment of this application;

[0039] Figure 4 is an exploded view of the vapor chamber in Figure 3;

[0040] Figure 5 is a bottom view of the internal structure of the heat exchange plate in Figure 3;

[0041] Figure 6 is a schematic diagram of another connection between a heat spreader and a heating element provided in an embodiment of this application;

[0042] Figure 7 is an exploded view of the protective shell of the heat spreader in Figure 6;

[0043] Figure 8 is an exploded view of a heat spreader provided in an embodiment of this application;

[0044] Figure 9 is a schematic diagram of another perspective of the exploded view in Figure 8;

[0045] Figure 10 is a schematic cross-sectional view of the shell of the heat spreader in Figure 8;

[0046] Figure 11 is a schematic cross-sectional view of the internal structure of the heat exchange plate in Figure 8;

[0047] Figure 12 is a schematic diagram of the cross-section at point AA in Figure 11;

[0048] Figure 13 is a schematic diagram of the laser welding path of the shell in Figure 10;

[0049] Figure 14 is an exploded view of another heat spreader provided in an embodiment of this application;

[0050] Figure 15 is a schematic cross-sectional view of the internal structure of the heat exchange plate in Figure 14;

[0051] Figure 16 is a schematic cross-sectional view of the internal structure of a heat exchanger provided in an embodiment of this application;

[0052] Figure 17 is an exploded view of another type of heat spreader provided in an embodiment of this application;

[0053] Figure 18 is a magnified view of part B in Figure 17;

[0054] Figure 19 is a schematic cross-sectional view of the internal structure of another heat exchanger provided in an embodiment of this application;

[0055] Figure 20 is a schematic diagram of another perspective of the exploded view in Figure 17;

[0056] Figure 21 is a magnified view of a portion of point C in Figure 20;

[0057] Figure 22 is a schematic cross-sectional view of the internal structure of another heat exchanger provided in an embodiment of this application;

[0058] Figure 23 is a schematic diagram of the overall structure of a heat spreader provided in an embodiment of this application;

[0059] Figure 24 is a flowchart of the fabrication method of the heat spreader in Figure 23.

[0060] Reference numerals: 01, Electronic device; 10, Display module; 11, Light-transmitting cover; 12, Display screen; 20, Housing; 21, Middle frame; 211, Frame; 212, Middle plate; 2120, Clearance groove; 22, Back cover; 30, Main board; 40, Battery; 50, Heating element; 60, Heat spreader; 61, Protective shell; 611, Base plate; 611a, First plate; 611b, Second plate; 611c, Third plate; 612, Top cover; 612a, First cover; 612b, Second cover; 612c, Third cover; 612d, Skirt; 62, Liquid absorbent core; 621, First area; 622, Second area; 71, Housing; 711, First cover; 711a, First part; 711b, Second part; 701, First surface; 7110, Protrusion; 712, Second cover plate; 712a, Third part; 712b, Fourth part; 702, Second surface; 710a, First recess; 710b, Second recess; 710c, First groove; 710d, Second groove; 72, Support structure; 721, Support column; 73, Fixing element; 730, Mounting hole; 100, Heat dissipation channel. Detailed Implementation

[0061] To make the purpose, technical solution, and advantages of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0062] In the description of this application, it should be clarified that the terms "vertical," "lateral," "longitudinal," "front," "rear," "left," "right," "up," "down," and "horizontal," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are merely for the convenience of describing this application, and do not mean that the device or element referred to must have a specific orientation or position, and therefore should not be construed as a limitation of this application. Similarly, the term "quantity" should not be construed as a limitation of this application.

[0063] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0064] This application provides an electronic device 01. Specifically, the electronic device 01 can be a portable electronic device or other types of electronic devices. For example, the electronic device 01 can be a mobile phone, a tablet personal computer, a laptop computer, a personal digital assistant (PDA), a monitor, a camera, a personal computer, a laptop computer, a wearable device, etc. For ease of explanation, the following description uses a mobile phone as an example of the electronic device 01.

[0065] Please refer to Figures 1 and 2. Figure 1 is a structural diagram of the electronic device 01 provided in an embodiment of this application, and Figure 2 is an exploded view of the electronic device 01 in Figure 1. As can be seen from the above, in this embodiment, the electronic device 01 is a mobile phone, and the electronic device 01 can have an approximately rectangular plate-like structure. The electronic device 01 may include a display module 10, a casing 20, a motherboard 30, a battery 40, and electronic components.

[0066] For ease of description below, an XYZ coordinate system is established, defining the width direction of electronic device 01 as the X-axis, the length direction of electronic device 01 as the Y-axis, and the thickness direction of electronic device 01 as the Z-axis. It should be noted that the coordinate system of electronic device 01 can be flexibly set according to actual needs; this application only provides an example and should not be considered a specific limitation thereof.

[0067] It is understood that Figures 1 and 2 only schematically show some of the components included in the electronic device 01, and the actual shape, size, location and construction of these components are not limited by Figures 1 and 2.

[0068] The aforementioned display module 10 is used to display images, videos, etc. The display module 10 may include a light-transmitting cover 11 and a display screen 12, with the light-transmitting cover 11 and the display screen 12 stacked together. The material of the light-transmitting cover 11 includes, but is not limited to, glass. For example, the light-transmitting cover 11 can be a common light-transmitting cover to protect the display screen from damage caused by external forces and to provide dust protection. Alternatively, the light-transmitting cover 11 can also be a touch-sensitive cover to enable the electronic device 01 to have touch functionality, thus making it more convenient for users. Therefore, this application does not specifically limit the material of the light-transmitting cover 11.

[0069] Furthermore, the aforementioned display screen 12 can be a flexible display screen or a rigid display screen. For example, the display screen 12 can be an organic light-emitting diode panel (OLED), an active-matrix organic light-emitting diode panel (AMOLED), a mini organic light-emitting diode panel, a micro light-emitting diode panel, a micro organic light-emitting diode panel, a quantum dot light-emitting diode panel (QLED), or a liquid crystal display panel (LCD).

[0070] The aforementioned housing 20 is used to protect and secure the electronic components inside the electronic device 01. The housing 20 may include a middle frame 21 and a rear cover 22. The rear cover 22 is located on the side of the display screen 12 away from the light-transmitting cover plate 11 and is stacked with the light-transmitting cover plate 11 and the display screen 12. The middle frame 21 is located between the light-transmitting cover plate 11 and the rear cover 22, and both the light-transmitting cover plate 11 and the rear cover 22 are fixed to the middle frame 21. For example, the rear cover 22 can be fixed to the middle frame 21 by means of adhesive bonding, threaded connection, welding, snap-fitting, etc. The light-transmitting cover plate 11 can be fixed to the middle frame 21 by adhesive bonding.

[0071] In some embodiments, the aforementioned middle frame 21 may include a side frame 211 and a middle plate 212. The side frame 211 is arranged around the middle plate 212, and the middle plate 212 is fixedly connected to the side frame 211. For example, the middle plate 212 and the side frame 211 can be fixedly connected by means of adhesive, threaded connection, welding, snap-fit, etc. Alternatively, the middle plate 212 and the side frame 211 may also be an integrally formed structure, that is, the middle plate 212 and the side frame 211 form a whole structural component, with no partition between the middle plate 212 and the side frame 211. Compared with a split structure, the integrally formed structure is more robust and convenient for assembly. The side frame 211 and the middle plate 212 enclose an accommodating space, in which the aforementioned motherboard 30, battery 40, and electronic components are all disposed.

[0072] The aforementioned motherboard 30 is used to set up the electronic components of the electronic device 01 and to realize the electrical connections between the electronic components. For example, the electronic components can be control chips (such as system-on-chips, SOCs), graphics processing units (GPUs), universal flash storage (UFS), etc.

[0073] The aforementioned electronic devices generate heat during operation, and these heat-generating electronic devices can also be referred to as heat-generating elements 50. To reduce the risk of damage to the heat-generating elements 50 due to overheating, the aforementioned electronic device may also include a vapor chamber 60 (VC), which is used to dissipate heat and cool the heat-generating elements 50.

[0074] For ease of description below, the thickness direction of the heat spreader 60 is the thickness direction (i.e., the Z-axis direction) of the electronic device 01, the length direction of the heat spreader 60 is the length direction (i.e., the Y-axis direction) of the electronic device 01, and the width direction of the heat spreader 60 is the width direction (i.e., the X-axis direction) of the electronic device 01; or, the width direction of the heat spreader 60 can be the length direction of the electronic device 01, and the length direction of the heat spreader 60 can be the width direction of the electronic device 01. Therefore, this application does not impose any special limitations on this.

[0075] Specifically, please refer to Figures 3, 4 and 5. Figure 3 is a schematic diagram of the connection between a heat spreader 60 and a heating element 50 provided in an embodiment of this application. Figure 4 is an exploded view of the structure of the heat spreader 60 in Figure 3. Figure 5 is a bottom view of the internal structure of the heat spreader 60 in Figure 3 (along the positive Z-axis).

[0076] The heat spreader 60 may include a protective shell 61 and a liquid absorbent core 62. The protective shell 61 may include a top cover 612 and a bottom plate 611. The top cover 612 includes a cover body 6121 and a skirt 6122 that is turned outward around the cover body 6121. The top cover 612 is fastened to the bottom plate 611, and its skirt 6122 is attached to and welded to the bottom plate 611. The cover body 6121 and the bottom plate 611 together form a receiving cavity. The liquid absorbent core 62 is disposed in the receiving cavity, and a heat dissipation channel 100 is formed between the side wall of the liquid absorbent core 62 and the inner wall of the protective shell 61. The liquid absorbent core 62 is also filled with a liquid working fluid. For example, the liquid working fluid may be deionized water, refrigerant, etc.

[0077] The absorbent core 62 may include a first region 621 and a second region 622. In use, the first region 621 of the absorbent core 62 may serve as its evaporation region, and part or all of the second region 622 may serve as its condensation region. Alternatively, part or all of the first region 621 may serve as its condensation region, and part or all of the second region 622 may serve as its evaporation region. This application does not impose any special limitations on this.

[0078] For ease of understanding, the following examples use the first region 621 of the liquid-absorbing core 62 as its evaporation region and the second region 622 as its condensation region.

[0079] At this time, the vertical projections of the heating element 50 and the first region 621 of the liquid absorption core 62 in the XY plane overlap with each other in at least a portion, that is, the heating element 50 is attached to the protective shell 61 at the position corresponding to the first region 621.

[0080] When the heat spreader 60 is heated, the liquid working fluid in the first region 621 of the liquid absorber 62 rapidly vaporizes to form steam. Driven by thermal diffusion, the steam flows through the heat dissipation channel 100 in the direction shown by the dashed arrow in Figure 5 to the second region 622, where it condenses into liquid and releases heat. The heat diffuses to the outside through the protective shell 61, and the liquid that enters the second region 622 flows back to the first region 621 by the capillary action of the liquid absorber. This cycle can effectively dissipate heat and cool the heating element 50.

[0081] As the density of components inside electronic device 01 increases and the volume of some components also increases, the heat spreader 60 may interfere with some components in the thickness direction of electronic device 01. Therefore, in some cases, it is necessary to design steps on the heat spreader 60 (i.e., the heat spreader 60 includes multiple segments, and the segments are not on the same plane) to avoid interference with other components.

[0082] For example, please refer to Figure 6, which is a schematic diagram of another connection between a heat spreader 60 and a heating element 50 provided in an embodiment of this application. The main board 30 and the intermediate board 212 are disposed opposite each other, and the heating element 50 is disposed on the main board 30 on the side closer to the intermediate board 212. The heat spreader 60 and the battery 40 are attached to the intermediate board 212, and the portion of the heat spreader 60 corresponding to the first region 621 (not shown in Figure 6) of the liquid-absorbing core 62 is sandwiched between the heating element 50 and the intermediate board 212.

[0083] To avoid the battery 40, in the orientation shown in Figure 6, the portion of the heat spreader 60 corresponding to the second region 622 (not shown in Figure 6) of the liquid absorber 62 "sinks" towards the middle plate 212 to form a step (i.e., the cross-section of the heat spreader 60 parallel to the YZ plane is Z-shaped). Correspondingly, a relief groove 2120 is provided on the middle plate 212 to accommodate the "sunken" portion of the heat spreader 60, so that the bottom of the heat spreader 60 fits against the relief groove 2120. The heat released by the vapor in the heat spreader 60 after condensation in the second region 622 is conducted through the protective shell 61 to the middle plate 212, then from the middle plate 212 to the frame 211, and finally dissipated into the external environment from the frame 211.

[0084] When manufacturing the stepped heat spreader 60, the step difference is generally created by placing the flat heat spreader 60 (as shown in Figure 3) into a mold and pressing it directly into shape using a cold pressing process. While this method can produce a stepped heat spreader 60, the cold pressing process can adversely affect the performance of the heat spreader 60. For example, the liquid absorption core 62 inside the heat spreader 60 may break during the cold pressing process, and the weld between the top cover 612 and the bottom plate 611 may crack.

[0085] For the reasons mentioned above, the top cover 612 and the bottom plate 611 of the protective shell 61 can be designed as structures with stepped edges, so that a heat spreader 60 with stepped edges can be directly obtained after welding the top cover 612 and the bottom plate 611. Please refer to Figure 7, which is an exploded view of the structure of the protective shell 61 of the heat spreader 60 in Figure 6. The bottom plate 611 may include a first plate 611a, a second plate 611b, and a third plate 611c. The first plate 611a and the third plate 611c are parallel to each other but not coplanar, and are spaced apart along the Y-axis. The second plate 611b is inclined between the first plate 611a and the third plate 611c, and its two ends are connected to the first plate 611a and the third plate 611c, respectively.

[0086] The cover body 6121 of the top cover 612 may include a first cover portion 612a, a second cover portion 612b and a third cover portion 612c. The first cover portion 612a and the third cover portion 612c are parallel to each other but not coplanar, and the first cover portion 612a and the third cover portion 612c are spaced apart along the Y-axis. The second cover portion 612b is inclinedly disposed between the first cover portion 612a and the third cover portion 612c, and the two ends of the second cover portion 612b are respectively connected to the first cover portion 612a and the third cover portion 612c. After the top cover 612 is fastened onto the bottom plate 611, the first cover part 612a is opposite to and parallel to the first plate 611a, the second cover part 612b is opposite to and parallel to the second plate 611b, and the third cover part 612c is opposite to and parallel to the third plate 611c. Correspondingly, the skirt 6122 is respectively attached to the first plate 611a, the second plate 611b, and the third plate 611c of the bottom plate 611.

[0087] During laser welding, the laser is focused on the surface of the skirt 6122 away from the base plate 611, and then the laser spot is moved around the cover 6121 along the skirt 6122 to weld the skirt 6122 and the base plate 611 together, thereby obtaining a temperature-controlled plate 60 with stepped differences.

[0088] However, since the skirt 6122 of the top cover 612 and the corresponding parts of the base plate 611 are not on the same plane, and the laser welding head is suspended above the top cover 612 and can only move in a horizontal plane, the distance between the laser welding head and the surface of the skirt 6122 away from the base plate 611 changes as the laser welding head moves. Therefore, the welding focal length needs to be adjusted according to the welding position on the skirt 6122 during laser welding, which results in low welding efficiency. Furthermore, if different welding focal lengths are used with the same welding power and welding speed, it may lead to local welding defects, such as incomplete welds and over-welding, resulting in a decrease in the yield of the heat spreader 60.

[0089] To address the aforementioned problems, this application provides a heat spreader 60, as shown in Figures 8, 9, 10, and 11. Figure 8 is an exploded view of the structure of the heat spreader 60 provided in this application embodiment; Figure 9 is a schematic diagram from another perspective of the exploded view in Figure 8; Figure 10 is a schematic cross-sectional view (parallel to the YZ plane) of the shell 71 of the heat spreader 60 in Figure 8; and Figure 11 is a schematic cross-sectional view (parallel to the YZ plane) of the internal structure of the heat spreader 60 in Figure 8. The heat spreader 60 may include the shell 71 and the aforementioned liquid-absorbing core 62.

[0090] Specifically, the housing 71 includes a first cover plate 711 and a second cover plate 712 disposed opposite to each other, the first cover plate 711 and the second cover plate 712 being parallel to the XY plane. The first cover plate 711 has a first surface 701 adjacent to the second cover plate 712, and the first cover plate 711 includes a first portion 711a and a second portion 711b, the first portion 711a extending around the second portion 711b. Along the Z-axis direction, the thickness h2 of the second portion 711b is greater than the thickness h1 of the first portion 711a, and the first portion 711a and the second portion 711b are flush on the first surface 701. A first recess 710a is provided on the side of the second portion 711b adjacent to the second cover plate 712. It should be noted that the first part 711a and the second part 711b being flush on the first surface 701 means that, in the orientation shown in Figure 8, the first surface 701 is a plane, that is, the end face of the first part 711a near the second cover plate 712 and the end face of the second part 711b near the second cover plate 712 are in the same plane.

[0091] The second cover plate 712 has a second surface 702 adjacent to the first cover plate 711. The second cover plate 712 includes a third portion 712a and a fourth portion 712b, with the third portion 712a extending around the fourth portion 712b. Along the Z-axis, the thickness h4 of the fourth portion 712b is greater than the thickness h3 of the third portion 712a, and the third portion 712a and the fourth portion 712b are flush on the second surface 702. A second recess 710b is provided on the side of the fourth portion 712b closest to the first cover plate 711. It should be noted that the third portion 712a and the fourth portion 712b being flush on the second surface 702 means that, in the orientation shown in Figure 9, the second surface 702 is a plane, that is, the end face of the third portion 712a closest to the first cover plate 711 and the end face of the fourth portion 712b closest to the first cover plate 711 are in the same plane.

[0092] In the thickness direction (parallel to the Z-axis) of the heat exchanger 60, a portion of the second part 711b overlaps with a portion of the fourth part 712b. It should be noted that the overlap of a portion of the second part 711b with a portion of the fourth part 712b means that, in the orientation shown in Figures 8 and 9, the vertical projection of a portion of the second part 711b onto the plane containing the first surface 701 (parallel to the XY plane) overlaps with the vertical projection of a portion of the fourth part 712b onto the plane containing the first surface 701.

[0093] The first recess 710a and the second recess 710b communicate to form a receiving cavity, and the liquid suction core 62 is disposed in the receiving cavity.

[0094] The heat spreader 60 provided in this application, through the aforementioned structural design of the first cover plate 711 and the second cover plate 712, can also achieve the formation of a step on the heat spreader 60. During production, it is only necessary to fix the first cover plate 711 and the second cover plate 712 on the fixture and make the first surface 701 and the second surface 702 fit together. Please continue to refer to Figure 10 and Figure 13. Figure 13 is a schematic diagram of the laser welding path of the shell 71 in Figure 10. The second cover plate 712 is clamped above the first cover plate 711. During laser welding, the laser welding head is suspended above the second cover plate 712, and the laser beam emitted by it is perpendicular to the surface of the third part 712a of the second cover plate 712 away from the first cover plate 711 (not shown in Figure 13). By controlling the movement of the laser welding head, the laser spot moves around the accommodating cavity formed by the second recess 710b and the first recess 710a along the edge area of ​​the third part 712a on the second cover plate 712. The dotted line in Figure 13 is the movement path of the laser spot, so as to weld the third part 712a of the second cover plate 712 and the first part 711a of the first cover plate 711 together, thus completing the sealing of the shell 71.

[0095] During the above welding process, the distance between the laser welding head and the surface of the third part 712a away from the first cover plate 711 remains constant. Therefore, one-time welding can be achieved without adjusting welding parameters (such as welding focal length, laser power, laser welding head moving speed, etc.), thereby improving welding efficiency, as well as the yield and stability of the heat spreader 60.

[0096] It is understood that the material of the aforementioned shell 71 can be copper, copper alloy, stainless steel, or other metals with high thermal conductivity and high structural strength. The materials of the first cover plate 711 and the second cover plate 712 can be the same or different.

[0097] The first cover plate 711 and one side surface of the absorbent core 62 can be in contact with each other or have a gap. The second cover plate 712 and the other side surface of the absorbent core 62 can be in contact with each other or have a gap. This application does not impose any special limitations on this. For example, please refer to Figure 12, which is a cross-sectional view of point AA in Figure 11. Along the Z-axis direction, the two side surfaces of the absorbent core 62 are in contact with the first cover plate 711 and the second cover plate 712 of the housing 71, respectively. That is, the depth of the first recess 710a (not shown in Figure 12) and the depth of the second recess 710b are equal to the thickness of the absorbent core 62. A heat dissipation channel 100 is formed between the side wall of the absorbent core 62 (the side wall parallel to the YZ plane) and the inner wall of the housing 71 (the inner wall parallel to the YZ plane).

[0098] Furthermore, the end of the first region 621 of the aforementioned absorbent core 62 that is away from the second region 622 may be located within the first recess 710a (correspondingly, the end of the second region 622 that is away from the first region 621 is located within the second recess 710b), or it may be located within the second recess 710b (correspondingly, the end of the second region 622 that is away from the first region 621 is located within the first recess 710a). As long as the absorbent core 62 extends from the second recess 710b to the first recess 710a, this application does not impose any special limitations on this.

[0099] For ease of understanding, the following examples will be described with the first region 621 of the liquid-absorbing core 62 located away from the second region 622 within the second recess 710b. In this case, when using the heat spreader 60, the fourth part 712b of the second cover plate 712 needs to be attached to the heating element 50, and the second part 711b of the first cover plate 711 needs to be attached to the bottom of the relief groove 2120 on the middle plate 212.

[0100] In the Y-axis direction, the first region 621 of the aforementioned absorbent core 62 can be entirely located within the second recess 710b, or it can be partially located within the second recess 710b and partially located within the first recess 710a. Similarly, the second region 622 of the absorbent core 62 can be entirely located within the first recess 710a, or it can be partially located within the first recess 710a and partially located within the second recess 710b. This application does not impose any special limitations on this.

[0101] In other words, the position of the step on the heat spreader 60 is set and adjusted according to the internal component layout of the electronic device 01, and the distribution of the first region 621 and the second region 622 of the liquid suction core 62 will not affect the position of the step. Specifically, the position of the step on the heat spreader 60 can be changed by adjusting the position of the second part 711b on the first cover plate 711, the size of the second part 711b and the first part 711a, the position of the fourth part 712b on the second cover plate 712, and the size of the fourth part 712b and the third part 712a.

[0102] For ease of understanding, the following examples will be described with the first region 621 of the absorbent core 62 located within the second recess 710b and the second region 622 located within the first recess 710a.

[0103] For example, in Figure 11 above, the first cover plate 711 and the second cover plate 712 have the same structure and dimensions. The second cover plate 712 is obtained by rotating the first cover plate 711 180° around the X-axis. The first region 621 of the liquid-absorbing core 62 is entirely located within the second recess 710b, and the second region 622 is entirely located within the first recess 710a.

[0104] In use, the heat spreader 60 in Figure 11 can have the fourth part 712b of the second cover plate 712 attached to the heating element 50, and the first cover plate 711 attached to the middle plate 212, with the second part 711b of the first cover plate 711 abutting the bottom surface of the clearance groove 2120 on the middle plate 212. The heat generated by the heating element 50 is conducted through the fourth part 712b of the second cover plate 712 to the first region 621 of the liquid-absorbing core 62. The liquid working fluid in the first region 621 rapidly vaporizes to form steam. Driven by thermal diffusion, the steam flows through the heat dissipation channel 100 (not shown in Figure 11) to the second region 622, where it condenses into liquid and releases heat. The heat is conducted through the second part 711b of the first cover plate 711 to the middle plate 212, then from the middle plate 212 to the frame 211, and finally diffused from the frame 211 into the external environment.

[0105] In some embodiments, please refer to Figures 14 and 15. Figure 14 is an exploded view of another heat spreader 60 provided in this application embodiment, and Figure 15 is a schematic cross-section (parallel to the YZ plane) of the internal structure of the heat spreader 60 in Figure 14. The heat spreader 60 may further include a support structure 72, which is supported between the liquid absorption core 62 and the first cover plate 711.

[0106] In this way, on the one hand, the support structure 72 can compress the liquid-absorbing core 62, making it fit tightly against the second cover plate 712, ensuring the heat transfer efficiency between the second cover plate 712 and the liquid-absorbing core 62. On the other hand, the support structure 72 can also cooperate with the liquid-absorbing core 62 to support the shell 71 of the heat spreader 60. When the heat spreader 60 is subjected to compression or impact, it can prevent the shell 71 from collapsing to a certain extent.

[0107] Furthermore, the support structure 72 also separates the liquid-absorbing core 62 from the first cover plate 711, so that a part of the space between the liquid-absorbing core 62 and the first cover plate 711 can also serve as a heat dissipation channel 100, thereby enabling the steam generated on the first region 621 to flow quickly to the second region 622, improving the evaporation and condensation cycle efficiency of the liquid working fluid, and thus helping to improve the heat dissipation efficiency of the heat spreader 60.

[0108] It is understood that the aforementioned support structure 72 may include multiple support columns 721 separately disposed in the housing 71 as shown in Figures 14 and 15. The multiple support columns 721 are distributed at intervals, one end of the support column 721 abuts against the first cover plate 711, and the other end of the support column 721 abuts against the liquid absorption core 62.

[0109] Alternatively, please refer to Figure 16, which is a schematic cross-section (parallel to the YZ plane) of the internal structure of a heat spreader 60 provided in an embodiment of this application. The aforementioned support structure 72 may include a plurality of protrusions 7110, wherein the protrusions 7110 are formed by a portion of the first cover plate 711 protruding towards the second cover plate 712, and the plurality of protrusions 7110 are spaced apart on the first portion 711a and the second portion 711b. That is to say, the protrusions 7110 are part of the first cover plate 711, and the protrusions 7110 and the first cover plate 711 are integrally formed. For example, in Figure 16, the protrusions 7110 are formed by stamping and stretching a portion of the first cover plate 711, and correspondingly, a recess is formed on the surface of the first cover plate 711 opposite to the second cover plate 712 in the area corresponding to the protrusions 7110.

[0110] Furthermore, the aforementioned protrusion 7110 and the first cover plate 711 can be integrally formed by processes such as casting, cutting, or 3D printing, which will not be elaborated here.

[0111] Based on the above, to reduce the thickness of the heat spreader 60, please refer to Figures 17, 18, and 19. Figure 17 is an exploded view (bottom view) of another heat spreader 60 provided in this application embodiment. Figure 18 is a partial enlarged view of point B in Figure 17. Figure 19 is a schematic diagram of the internal structure cross-section (parallel to the YZ plane) of another heat spreader 60 provided in this application embodiment. Specifically, a first groove 710c is provided on the third part 712a of the second cover plate 712 near the second part 711b of the first cover plate 711. The first groove 710c communicates with the second recess 710b, and the second region 622 of the liquid absorption core 62 is located within the first groove 710c.

[0112] In this way, on the one hand, it is equivalent to embedding a portion of the second region 622 of the liquid-absorbing core 62 into the third portion 712a of the second cover plate 712, thereby reducing the depth of the first recess 710a in the Z-axis direction for accommodating the second region 622, and consequently reducing the thickness of the second portion 711b of the first cover plate 711, thus reducing the overall thickness of the heat spreader 60, which is beneficial for the thinning and lightening of the electronic device 01. On the other hand, by opening the first groove 710c, the material thickness of the second cover plate 712 at the bottom of the first groove 710c is reduced, allowing the heat released during vapor condensation to be released to the surrounding environment more quickly through the second cover plate 712, which is beneficial for improving the heat dissipation efficiency of the heat spreader 60.

[0113] Further, please refer to Figure 19, and in conjunction with Figures 20 and 21. Figure 20 is a schematic diagram from another perspective of the exploded view in Figure 17, and Figure 21 is a partial enlarged view of point C in Figure 20. Specifically, a second groove 710d may be provided on the side of the first portion 711a of the first cover plate 711 near the fourth portion 712b of the second cover plate 712. The second groove 710d communicates with the first recess 710a.

[0114] For example, please continue to refer to Figure 19. The temperature distribution plate 60 does not have a support structure 72. Along the Z-axis, the two side surfaces of the liquid absorption core 62 are respectively attached to the first cover plate 711 and the second cover plate 712.

[0115] At this time, a portion of the second region 622 of the absorbent core 62 is located within the first groove 710c. A portion of the first region 621 is located within the second groove 710d, which is equivalent to embedding a portion of the first region 621 into the first portion 711a of the first cover plate 711. This reduces the depth of the second recess 710b in the Z-axis direction for accommodating the first region 621, and consequently reduces the thickness of the fourth portion 712b of the second cover plate 712. This reduces the overall thickness of the heat spreader 60, which is beneficial for the thinning of the electronic device 01. On the other hand, by opening the second groove 710d, the material thickness of the first cover plate 711 at the bottom of the second groove 710d is reduced, allowing more heat from the heating element 50 to be conducted along the Z-axis direction through the fourth portion 712b of the second cover plate 712 → the first region 621 of the absorbent core 62 → the first portion 711a of the first cover plate 711 to the middle plate 212, which is beneficial for improving the heat dissipation efficiency of the heat spreader 60.

[0116] For example, please refer to Figure 22, which is a schematic cross-section (parallel to the YZ plane) of the internal structure of another heat spreader 60 provided in this application embodiment. Multiple support columns 721 are provided inside the heat spreader 60, and the liquid absorption core 62 is only attached to the second cover plate 712. The support columns 721 are supported between the first cover plate 711 and the liquid absorption core 62.

[0117] At this time, a portion of the second region 622 of the liquid-absorbing core 62 is located within the first groove 710c, thereby reducing the depth of the first recess 710a in the Z-axis direction for accommodating the second region 622 and the support column 721, and consequently reducing the thickness of the second portion 711b of the first cover plate 711. A portion of the support column 721 is located within the second groove 710d, thereby reducing the depth of the second recess 710b in the Z-axis direction for accommodating the first region 621 and the support column 721, and consequently reducing the thickness of the fourth portion 712b of the second cover plate 712, thus reducing the overall thickness of the heat spreader 60.

[0118] In some embodiments, please refer to Figure 23, which is a schematic diagram of the overall structure of a heat spreader 60 provided in an embodiment of this application. The heat spreader 60 may also include a fixing member 73. The fixing member 73 is fixed to the housing 71 and is used to install and fix the heat spreader 60 so that the heat spreader 60 is in close contact with the heating element 50 and the middle plate 212.

[0119] It is understood that the aforementioned fastener 73 can be connected to the first part 711a of the first cover plate 711 or to the third part 712a of the second cover plate 712, and this application does not make any special limitation in this regard.

[0120] Further, referring to Figure 23, the fixing member 73 is provided with a mounting hole 730, which penetrates the fixing member 73 along the thickness direction of the heat exchange plate 60 (parallel to the Z-axis). In this way, the heat exchange plate 60 can be fixed to the middle plate 212 by using fasteners passing through the mounting hole 730. Correspondingly, the middle plate 212 is also provided with assembly holes that mate with the fasteners.

[0121] It is understood that the fasteners mentioned above can be screws, rivets, clips, etc., and this application does not make any special limitations on them.

[0122] This application embodiment also provides a method for manufacturing a heat spreader 60. Taking the heat spreader 60 shown in FIG23 as an example, FIG24 is a flowchart of the manufacturing method of the heat spreader 60 in FIG23. The method specifically includes the following steps:

[0123] S1. The second portion 711b of the first cover plate 711 is stamped and stretched to form a first recess 710a on the first cover plate 711. The fourth portion 712b of the second cover plate 712 is stamped and stretched to form a second recess 710b on the second cover plate 712.

[0124] S2. An injection hole is made on the first cover plate 711 or the second cover plate 712;

[0125] For example, injection holes can be formed by drilling or punching.

[0126] S3. Attach the liquid-absorbing core 62 to the second cover plate 712.

[0127] Specifically, the absorbent core 62 extends from the bottom of the second recess 710b to the third portion 712a.

[0128] S4. Multiple support columns 721 are provided at intervals on the side of the liquid-absorbing core 62 away from the second cover plate 712.

[0129] S5. Fasten the first cover plate 711 and the second cover plate 712 together;

[0130] Specifically, after being fastened, a portion of the second part 711b of the first cover plate 711 overlaps with a portion of the fourth part 712b of the second cover plate 712 in the Z-axis direction, and the first recess 710a and the second recess 710b communicate to form a receiving cavity. The first region 621 of the liquid-absorbing core 62 is located in the second recess 710b, the second region 622 is located in the first recess 710a, and the support column 721 abuts against the first cover plate 711.

[0131] S6. Laser welding is used to weld the first part 711a of the first cover plate 711 to the third part 712a of the second cover plate 712 together.

[0132] Specifically, the first cover plate 711 and the second cover plate 712, after being fastened together, are placed on a fixture, with the second cover plate 712 positioned between the first cover plate 711 and the laser welding head. Then, the laser spot is directed to circle the receiving cavity formed by the first recess 710a and the second recess 710b on the surface of the third part 712a of the second cover plate 712 away from the first cover plate 711, thereby welding the edge region of the first part 711a to the edge region of the third part 712a together.

[0133] S7. Inject liquid working fluid into the accommodating cavity through the injection hole, and then seal the injection hole.

[0134] S8. Weld fastener 73 onto housing 71 to complete the manufacturing process.

[0135] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0136] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A heat spreader, characterized in that, include: A housing, the housing comprising a first cover plate and a second cover plate disposed opposite to each other; The first cover plate has a first surface close to the second cover plate. The first cover plate includes a first part and a second part. The first part extends around the second part. The thickness of the second part is greater than the thickness of the first part. The first part and the second part are flush with the first surface. A first recess is provided on the side of the second part close to the second cover plate. The second cover plate has a second surface close to the first cover plate. The second cover plate includes a third part and a fourth part. The third part extends around the fourth part. The thickness of the fourth part is greater than the thickness of the third part. The third part and the fourth part are flush on the second surface. A second recess is provided on the side of the fourth part close to the first cover plate. In the thickness direction of the heat exchange plate, a part of the second part overlaps with a part of the fourth part, and the first recessed part communicates with the second recessed part to form an accommodating cavity; A liquid-absorbing core is disposed within the accommodating cavity.

2. The temperature distribution plate according to claim 1, characterized in that, The absorbent core is attached to the second cover plate. The absorbent core includes a first region and a second region connected to each other. The first region is at least partially located within the second recess, and the second region is at least partially located within the first recess.

3. The temperature distribution plate according to claim 2, characterized in that, The third part has a first groove on the side near the second part, the first groove is connected to the second recess, and the second region is located in the first groove.

4. The temperature distribution plate according to claim 2 or 3, characterized in that, A second groove is provided on the side of the first part near the fourth part, and the second groove communicates with the first recess.

5. The temperature distribution plate according to any one of claims 2 to 4, characterized in that, The temperature equalization plate also includes a support structure, which is supported between the liquid absorption core and the first cover plate.

6. The temperature distribution plate according to claim 5, characterized in that, The support structure includes multiple support columns, which are spaced apart. One end of each support column abuts against the first cover plate, and the other end of each support column abuts against the liquid-absorbing core.

7. The temperature distribution plate according to claim 5, characterized in that, A portion of the first cover plate protrudes towards the second cover plate to form the support structure.

8. The temperature distribution plate according to any one of claims 1 to 7, characterized in that, The temperature distribution plate also includes a fixing member, which is connected to the outside of the housing and is used to install and fix the temperature distribution plate.

9. The temperature distribution plate according to claim 8, characterized in that, The fixing member is provided with mounting holes, which penetrate the fixing member along the thickness direction of the heat exchange plate.

10. The temperature distribution plate according to any one of claims 1 to 9, characterized in that, The temperature distribution plate also includes a liquid working fluid, which is filled inside the liquid absorption core.

11. An electronic device, characterized in that, include: shell; The heating element is disposed inside the housing; The heat spreader is the heat spreader according to any one of claims 1 to 10, wherein the heat spreader is disposed inside the outer casing and is attached to the heating element.

12. A method for manufacturing a heat spreader, characterized in that, The method includes: A first cover plate is stamped to form a first recess on the first cover plate; wherein the first cover plate includes a first part and a second part, the first part extends around the second part, and the first recess is formed by stamping the second part; The second cover plate is stamped to form a second recess on the second cover plate; wherein the second cover plate includes a third part and a fourth part, the third part extends around the fourth part, and the second recess is formed by stamping the fourth part; The absorbent core is attached to the second cover plate; Fasten the first cover plate and the second cover plate together; The first part and the third part are welded together using laser welding to obtain the heat spreader.

13. The method for manufacturing a heat spreader according to claim 12, characterized in that, Before attaching the absorbent core to the second cover plate, the method further includes: An injection hole is made on the first cover plate or the second cover plate.

14. The method for manufacturing a heat spreader according to claim 13, characterized in that, After the first part and the third part are welded together using laser welding, the method further includes: Liquid working fluid is injected into the first recess or the second recess through the injection hole; Seal the injection hole.

15. The method for manufacturing a heat spreader according to any one of claims 12 to 14, characterized in that, Before fastening the first cover plate and the second cover plate together, the method further includes: Multiple support columns are provided on the side of the liquid-absorbing core away from the second cover plate, and the multiple support columns are distributed at intervals.

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