Loop heat pipe structure and electronic device

Abstract

This invention discloses a loop heat pipe structure and electronic device. The loop heat pipe structure includes an evaporator, a steam pipe, a condenser, and a liquid pipe connected in sequence. The evaporator includes a housing and a capillary wick unit disposed within the housing. A steam outlet and a liquid inlet are spaced apart along the Y-direction on one side of the housing. The capillary wick unit includes a capillary wick, which comprises a main body extending along the X-direction and corresponding to the liquid inlet position, and multiple branch portions spaced apart along the X-direction on the main body. The branch portions extend at a predetermined angle to the X-direction, with the extension length gradually increasing from the side with the steam outlet to the opposite side to reserve a steam convergence channel communicating with the steam outlet. At least a portion of the steam pipe and liquid pipe is a flexible pipe. The electronic device includes the above-described loop heat pipe structure. This invention facilitates shortening the pipe layout length, reducing space and weight occupation, and enables efficient heat transfer across regions and over long distances.

Description

Technical Field

[0001] This invention belongs to the field of heat dissipation technology for electronic components, and particularly relates to a miniaturized, bendable loop heat pipe structure and electronic device. Background Technology

[0002] With advancements in electronic information technology and microcomputer processing technology, the performance of mobile electronic devices (such as mobile phones, tablets, AR / VR glasses, etc.) is constantly improving, while their size is continuously shrinking, leading to a continuous increase in chip heat dissipation. Currently, these electronic devices generally employ a heat dissipation solution that combines thermal conduction, natural convection, and radiation. This involves attaching a heat-spreading material (such as graphite sheets, copper sheets, heat spreaders, or thermally conductive structures) directly above the chip to transfer heat to the casing. Then, through natural convection and radiation between the casing and the environment, the heat is dissipated into the surroundings.

[0003] However, most existing heat-conducting structures are rigid loop heat pipe structures, which are large in size, occupy a lot of space for pipe layout, and have poor heat transfer performance. In addition, for electronic devices with hinged parts, such as tablet computers and AR / VR glasses, traditional rigid loop heat pipe structures can only conduct heat to the shell area near the chip, and cannot make full use of the remaining shell parts (such as the frame of AR / VR glasses or the screen of tablet computers) for cross-regional and long-distance heat transfer; resulting in poor heat dissipation of electronic devices. Summary of the Invention

[0004] In order to overcome at least one of the shortcomings of the prior art, the present invention provides a loop heat pipe structure, which facilitates the shortening of pipe layout length, reduces space and weight occupation, and enables heat transfer across regions and over long distances.

[0005] As part of the same inventive concept, this invention also provides an electronic device that is advantageous for making full use of its own surface area to achieve effective heat dissipation, resulting in good heat dissipation performance.

[0006] To address the problems existing in the prior art, embodiments of the present invention provide a loop heat pipe structure, including an evaporator, a steam pipe, a condenser, and a liquid pipe connected in sequence; the evaporator includes an encapsulation shell and a capillary wick unit disposed within the encapsulation shell; the encapsulation shell has a steam outlet for connecting to one end of the steam pipe and a liquid inlet for connecting to one end of the liquid pipe formed at intervals along the Y direction on the side facing the condenser;

[0007] The capillary core unit includes a capillary core, which includes a main body extending along the X direction and a plurality of branch portions spaced apart along the X direction on the main body. The main body corresponds to the liquid inlet position. The branch portions extend along a direction forming a preset angle with the X direction, and from the side where the steam outlet is located to the opposite side, the extension length of the branch portions gradually increases to reserve a steam gathering channel communicating with the steam outlet.

[0008] At least a portion of the steam pipeline and at least a portion of the liquid pipeline are respectively configured as flexible pipes.

[0009] As a further improvement, an elastic skeleton is fitted onto the flexible tube.

[0010] As a further improvement, the condenser includes a serpentine tube, the two ends of which are respectively connected to the steam line and the liquid line;

[0011] Alternatively, the condenser includes a condensing shell with a serpentine or U-shaped channel formed inside. The condensing shell has a steam inlet and a liquid outlet spaced along the Y direction on the side facing the evaporator, corresponding to the two ends of the serpentine or U-shaped channel. The other end of the steam pipe is connected to the steam inlet, and the other end of the liquid pipe is connected to the liquid outlet.

[0012] As a further improvement, the two ends of the steam pipeline are welded to the steam inlet and the steam outlet, respectively, or sealed and connected via adapters; the two ends of the liquid pipeline are welded to the liquid inlet and the liquid outlet, or sealed and connected via adapters.

[0013] As a further improvement, the encapsulation shell includes a base plate and a cover that snap together along the Z direction; the cover includes a cover body and an edge portion connected together.

[0014] The edge portion is fitted and sealed to the base plate, and the base plate and the cover are fastened together to form a connected mounting cavity, the steam outlet and the liquid inlet; the capillary core unit is disposed in the mounting cavity.

[0015] As a further improvement, the cover body is formed with an installation groove and two first and second flow grooves that are on the same side and spaced apart along the Y direction; the installation groove, the first flow groove and the second flow groove, together with the bottom plate, respectively enclose the installation cavity, the steam outlet and the liquid inlet.

[0016] As a further improvement, a third flow groove is also formed on the cover body; the third flow groove and the bottom plate surround a vacuum filling port; the vacuum filling port is located near the liquid inlet and is located on the same side or adjacent to each other.

[0017] As a further improvement, the end face of the branch near the steam outlet along the Y direction and away from the main body is flush with the inner wall of the side of the steam outlet facing the liquid inlet.

[0018] As a further improvement, the capillary core unit also includes a first metal wire mesh structure and a second metal wire mesh structure located on both sides of the capillary core along the Z direction and conformally adapted to the mounting cavity; the first metal wire structure is attached to the base plate, and the second metal wire mesh structure is attached to the cover.

[0019] As a further improvement, the first metal wire mesh structure, the capillary core, and the base plate are an integrated sintered structure.

[0020] As a further improvement, the overall thickness of the capillary core unit is greater than the depth of the mounting cavity along the Z direction.

[0021] As a further improvement, the evaporator is manufactured based on a manufacturing mold; the manufacturing mold includes a mold base, a mold body, and a mold cap arranged sequentially from bottom to top, as well as a locking element for locking and fixing the three together; the manufacturing steps include:

[0022] S1. Place the base plate, the first metal wire mesh structure, and the mold body onto the mold base in sequence from bottom to top; fill the capillary core forming cavity on the mold body with metal powder and a pore-forming agent; wherein the mass fraction of the pore-forming agent is 10% to 20%;

[0023] S2. After filling, cover the mold cap and use the locking device to lock the manufacturing mold for pre-tightening and pressurization; then place the entire manufacturing mold into a vacuum sintering furnace for sintering; nitrogen or argon is used for gas protection during the sintering process.

[0024] S3. After sintering, open the mold cover, take out the integrated sintered structure, and then put it into deionized water. After the pore-forming agent is completely dissolved, put it into a vacuum drying oven to dry.

[0025] S4. Place the second metal wire mesh structure on the integrated sintered structure, then fasten the cover, and weld the second metal wire mesh structure to the cover using a medium-frequency diffusion welding method, while simultaneously completing the sealing connection between the base plate and the edge of the cover; the evaporator is now complete.

[0026] As a further improvement, the pore-forming agent is Na2CO3 or NaCl particles.

[0027] As a further improvement, the mold cover is provided with a contour pressing head adapted to the capillary core forming cavity, and the mold base is provided with a base plate positioning groove for positioning the base plate.

[0028] Another embodiment of the present invention provides an electronic device, including a first component and at least one second component hinged to the first component; it also includes the above-described loop heat pipe structure;

[0029] The evaporator is arranged in the first component, which is the hot end, and abuts against the heat dissipation device disposed thereon. The flexible tube is located at the hinge. The condenser is arranged in one of the second components, which is the cold end.

[0030] Alternatively, the evaporator is arranged within one of the second components, which serves as the hot end, and abuts against the heat dissipation device disposed thereon, with the flexible tube located at the hinge, and the condenser arranged within the first component, which serves as the cold end.

[0031] Alternatively, the evaporator is arranged within one of the second components, which serves as the hot end, and abuts against the heat dissipation device disposed thereon, with the flexible tube located at the hinge, and the condenser is arranged within the other of the second components, which serves as the cold end.

[0032] The beneficial effects achieved by this invention due to the adoption of the above technical solution are as follows:

[0033] The loop heat pipe structure of this invention includes an evaporator, a steam pipe, a condenser, and a liquid pipe connected in sequence. The evaporator includes a housing and a capillary wick unit disposed within the housing. On the same side of the housing, a steam outlet for connecting to one end of the steam pipe and a liquid inlet for connecting to one end of the liquid pipe are formed at intervals along the Y direction. The capillary wick unit includes a capillary wick, which includes a main body extending along the X direction and multiple branches spaced at intervals along the X direction on the main body. The main body corresponds to the liquid inlet position. The branches extend at a predetermined angle to the X direction, and their extension length gradually increases from the side where the steam outlet is located to the opposite side, thus reserving a steam convergence channel communicating with the steam outlet. At least a portion of the steam pipe and at least a portion of the liquid pipe are respectively configured as flexible pipes. An electronic device includes the above-described loop heat pipe structure, with its flexible pipe located at the hinge of the electronic device.

[0034] In this invention, the reserved steam gathering channel facilitates the same-side setting of the steam outlet and liquid inlet, which can minimize the length of the steam and liquid pipelines, reducing space and weight. Furthermore, the unequal lengths of the multiple branches extending along the Y direction can effectively prevent collapse during vacuuming due to excessive reserved steam gathering channel. In addition, the flexible tube design facilitates efficient heat transfer across regions and over long distances when used in electronic equipment.

[0035] In summary, this invention facilitates the shortening of pipeline layout length, reduces space and weight occupation, and enables efficient heat transfer across regions and over long distances. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This is a schematic diagram of the first embodiment of the loop heat pipe structure of the present invention;

[0038] Figure 2 yes Figure 1 Schematic diagram of the structure of the evaporator

[0039] Figure 3 yes Figure 2 Exploded structural diagram;

[0040] Figure 4 yes Figure 3 Schematic diagram of the installation positions of the medium capillary core and the cover;

[0041] Figure 5 yes Figure 1 Exploded view of the intermediate condenser;

[0042] Figure 6 This is a schematic diagram of the evaporator structure in the second embodiment of the loop heat pipe structure of the present invention;

[0043] Figure 7 yes Figure 6 Schematic diagram showing the positions of the middle capillary core, the first metal wire mesh, and the cover;

[0044] Figure 8 This is a schematic diagram of the condenser structure in the third embodiment of the loop heat pipe structure of the present invention;

[0045] Figure 9 This is an exploded structural diagram of the first embodiment of the smart glasses of the present invention;

[0046] Figure 10 This is an exploded structural diagram of a second embodiment of the smart glasses of the present invention;

[0047] Figure 11 This is an exploded view of the folding receiver of the present invention;

[0048] Figure 12 This is an exploded view of the structure of the tablet computer of the present invention;

[0049] Figure 13 This is a reference diagram showing the application of the manufacturing mold in the evaporator manufacturing process of the present invention;

[0050] In the diagram: 1-Evaporator, 11-Encapsulation shell, 111-Base plate, 112-Cover, 1121-Cover body, 1122-Edge, 1123-Mounting groove, 1124-First flow channel, 1125-Second flow channel, 1126-Third flow channel, 113-Steam gathering channel, 114-Steam outlet, 115-Liquid inlet, 116-Vacuum filling port, 12-Capillary wick unit, 121-Capillary wick, 1211-Main body, 1212-Branch, 122-First wire mesh structure, 123-Second wire mesh structure, 2-Steam pipeline, 3-Cold Condenser, 31-Serpentine tube, 32-Condensing shell, 321-U-shaped groove, 322-Straight groove, 32a-Upper plate, 32b-Lower plate, 4-Liquid pipeline, 5-Spring frame, 6-Adapter, 7-Smart glasses, 71-Frame, 72-Template, 73-Hinge, 8-Folding phone, 81-Main body, 82-Folding body, 9-Laptop, 91-Computer main body, 92-Computer display, c-Device to be cooled, 10-Manufacturing mold, 101-Mold base, 1011-Base plate positioning groove, 102-Mold body, 1021-Capillary core forming cavity, 103-Mold cap. Detailed Implementation

[0051] It should be noted that if the present invention involves directional indicators, such as X, Y, Z, etc., the directional indicators are only used to explain the relative positional relationship between the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0052] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0053] Depend on Figures 1 to 4As shown in the figure, one embodiment of the present invention discloses a loop heat pipe structure, including an evaporator 1, a steam pipe 2, a condenser 3, and a liquid pipe 4 connected in sequence; the evaporator 1 includes a housing 11 and a capillary wick unit 12 disposed in the mounting cavity of the housing 11; the housing 11 has a steam outlet 114 for connecting to one end of the steam pipe 2 and a liquid inlet 115 for connecting to one end of the liquid pipe 4 at intervals along the Y direction on the side facing the condenser 3; wherein, the capillary wick unit 12 includes a capillary wick 121, and the capillary wick 121 includes a body extending along the X direction (i.e., extending in the direction of the liquid inlet 115). The main body 1211 comprises a main body 1211 and a plurality of branch portions 1212 spaced apart along the X-direction. The main body 1211 corresponds to the liquid inlet 115. Specifically, one end face of the main body 1211 along the X-direction covers the liquid inlet 115. The branch portions 1212 extend along a direction forming a predetermined angle with the X-direction, and from the side where the steam outlet 114 is located to the opposite side, the extension length of the branch portions 1212 gradually increases to reserve a steam gathering channel 113 communicating with the steam outlet 114. At least a portion of the steam pipeline 2 and at least a portion of the liquid pipeline 4 are respectively configured as flexible pipes. The two ends of the main body 1211 along the X-direction abut against the corresponding inner walls of the encapsulation shell 11.

[0054] "At least part of the pipe section" means: a part of the pipe section, two parts of the pipe section, multiple parts of the pipe section, or all of the pipe section.

[0055] The working principle of this loop heat pipe structure is as follows: The evaporator 1 is tightly attached to the device to be cooled, and the heat is conducted to the mounting cavity of the evaporator 1. The working fluid in the capillary wick unit 12 absorbs heat and turns into steam. The steam enters the steam outlet 114 through the steam channel between the two branches and the steam gathering channel 113. Then it enters the condenser 3 through the steam pipe 2, releases heat and turns into liquid. Then it enters the liquid pipe 4, and finally enters the evaporator 1 under the action of capillary force to enter the next heat exchange cycle, thus realizing heat transfer.

[0056] In this embodiment, the reserved steam gathering channel 113 facilitates the same-side setting of steam outlet 114 and liquid inlet 115. Compared with setting them on opposite sides, this can minimize the length of steam pipeline 2 and liquid pipeline 4, reducing space and weight. Furthermore, the varying lengths of the multiple branches 1212 extending along the Y direction can effectively prevent collapse during vacuuming due to excessive reserved steam gathering channel 113. In addition, the flexible tube design facilitates efficient heat transfer across regions and over long distances when used in electronic devices.

[0057] In other embodiments of the present invention, an elastic skeleton, such as a spring skeleton 5 (preferably a metal spring), is fitted onto the flexible tube; this arrangement can locally strengthen the flexible tube and improve its bending resistance; it can effectively prevent the flexible tube from sinking at the hinge of electronic products, which would increase flow resistance, or from breaking or leaking due to repeated bending.

[0058] In other embodiments, such as Figure 4 As shown, the main body 1211 is disposed on a first side of the encapsulation shell 11 along the Y direction and extends along the direction of the encapsulation shell 11. On the other side of the main body 1211 opposite to this side, a plurality of spaced branches 1212 are connected. The branches 1212 extend along a direction at a certain angle (e.g., 90 degrees, extending in the Y direction) to the extending direction of the main body 1211, and the length of at least one branch 1212 is different from the length of the other branches 1212. The encapsulation shell 11 also includes a second side disposed opposite to the first side, and a third side located between the first and second sides and close to the condenser 3. A steam outlet 114 and a liquid inlet 115 are spaced apart on the third side of the encapsulation shell 11, with the liquid inlet 115 close to the first side of the encapsulation shell 11 and the steam outlet 114 close to the second side of the encapsulation shell 11.

[0059] In some embodiments, a steam gathering channel 113 is formed between the branch 1212 and the second side of the encapsulation shell 11, through which steam quickly reaches the steam outlet 114.

[0060] The length of the branch 1212 closest to the third side of the package 11 is less than the length of the branch 1212 closest to the fourth side of the package 11 (i.e.) Figure 4 The leftmost branch 1212 is shorter than the rightmost branch 1212. The fourth side of the encapsulation shell 11 is located between the first side and the second side of the encapsulation shell 11 and is opposite to the third side of the encapsulation shell 11. In some embodiments, the length of the branch 1212 closest to the third side of the encapsulation shell 11 may be less than the length of any other branch 1212, or less than the length of some branches 1212.

[0061] In order to accelerate the flow of steam from the encapsulation shell 11 to the steam outlet 114, the branch 1212, which is closest to the third side of the encapsulation shell 11, has its end away from the main body 1211 flush with the side wall of the steam outlet 114 facing the liquid inlet 115, so as to completely not block the steam outlet 114.

[0062] In some embodiments of the present invention, the condenser 3 includes a condensing shell 32, within which a serpentine or U-shaped channel is formed. On the same side of the condensing shell 32, a steam inlet and a liquid outlet are spaced apart along the Y direction, corresponding to the two ends of the serpentine or U-shaped channel. The other end of the steam pipe 2 is connected to the steam inlet, and the other end of the liquid pipe 4 is connected to the liquid outlet. Figure 5 As shown, in one specific embodiment, the condenser shell 32 includes an upper plate 32a and a lower plate 32b that are welded together. Both the upper plate 32a and the lower plate 32b include a first main portion and two first extension portions spaced apart along the Y direction on the first main portion. The first main portion has a U-shaped groove 321, and the first extension portions have straight grooves 322 communicating with one end of the U-shaped groove 321. The two U-shaped grooves 321 form a U-shaped channel, the straight grooves 322 on the two opposing first extension portions form a steam inlet, and the straight grooves 322 on the other two opposing first extension portions form a liquid outlet. In this embodiment, the thickness of the condenser shell 32 does not exceed 1 mm, and the upper plate 32a and the lower plate 32b are sealed together using diffusion welding, brazing, or laser welding processes.

[0063] In another specific embodiment, the condenser shell 32 includes a base plate and a cover that are snapped together; the structure of the cover is the same as that of the upper plate 32a described above (see...). Figure 5 The structures are the same, except that the U-shaped channel, steam inlet, and liquid outlet are enclosed by corresponding grooves and substrates. The serpentine or U-shaped channel arrangement increases the heat exchange path and improves thermal efficiency. Furthermore, the same-side arrangement of the steam inlet and liquid outlet further minimizes the length of the steam pipe 2 and liquid pipe 4 between the evaporator 1 and condenser 3, reducing size, weight, and flow resistance. Therefore, the condenser shell 32 can have many structures; as long as it has a serpentine or U-shaped channel, steam inlet, and liquid outlet, other structures are not listed here.

[0064] In another specific embodiment, by Figure 8 As shown, the condenser 3 includes a serpentine tube 31, with its two ends on the same side connected to a steam pipe 2 and a liquid pipe 4, respectively; the steam pipe 2 and the liquid pipe 4 are arranged in parallel between the evaporator 1 and the condenser 3. This embodiment is suitable for use in electronic devices with large housings, such as laptops.

[0065] This invention Figure 1 In one specific embodiment shown, the encapsulation shell 11 and the condenser shell 32 are flat structures, the steam outlet 114, the liquid inlet 115, the steam inlet, and the liquid outlet are flat openings, while the liquid pipeline 4 and the steam pipeline 2 are cylindrical structures; therefore, both ends of the steam pipeline 2 are sealed to the steam inlet and steam outlet 114 respectively via adapter 6; both ends of the liquid pipeline 4 are sealed to the liquid inlet 115 and liquid outlet via adapter 6. In another specific embodiment, by Figure 1and Figure 4 As shown, the adapter 6 has a funnel-shaped structure. The first end of the adapter 6 is connected to the evaporator 1 / condenser 3, and the second end is connected to the steam line 2 / liquid line 4. The width of the first end is greater than the width of the second end. The width of the steam outlet 114 and the liquid inlet 115 is less than the width of the first end of the adapter 6, but greater than the width of the steam line 2 and the liquid line 4, respectively.

[0066] In addition, the outer walls of at least both ends of the liquid pipeline 4 and the steam pipeline 2 are coated with a polymer film, which helps to improve the sealing performance of the pipeline and facilitates a sealed connection with the adapter 6. Optionally, the material of the adapter 6 is the same as that of the evaporator 1 and the condenser 3 (metal materials such as copper, aluminum or stainless steel) to facilitate welding or bonding.

[0067] In some embodiments, the liquid pipeline 4 and the steam pipeline 2 are flat pipes adapted to flat openings. In this case, a sealed connection can be achieved by adding a sealing ring through insertion or welding. Based on the above, the sealing connection method with the steam outlet 114, liquid inlet 115, steam inlet, and liquid outlet can be reasonably selected according to the structure of the liquid pipeline 4 and the steam pipeline 2, which will not be elaborated here.

[0068] Optionally, the flexible pipe is made of a flexible, lightweight polymer material with high barrier properties, such as polyethylene (PE), polyamide (PA), or Teflon (PTFE). This polymer material has advantages such as stable physical and chemical properties, good temperature resistance, and strong vapor barrier properties. Therefore, the flexible pipe made of these polymer materials is lighter and more flexible in layout than the traditional metal corrugated hose.

[0069] In some embodiments of the present invention, the encapsulation shell 11 includes a base plate 111 and a cover 112 that are fastened together along the Z-direction; the cover 112 includes a cover body 1121 and an edge portion 1122 connected together; the edge portion 1122 is attached to the base plate 111 and sealed together by processes such as diffusion welding, brazing, and laser welding. After the base plate 111 and the cover 112 are fastened and sealed together, they form a connected mounting cavity, a steam outlet 114, and a liquid inlet 115; the capillary wick unit 12 is disposed in the mounting cavity. The base plate 111 and the cover 112 can be formed by processes such as wet etching, stamping, and machining.

[0070] Depend on Figure 3 and Figure 4As shown, in a specific embodiment of the present invention, the cover body 1121 includes a second main portion and two second extension portions disposed on the same side and spaced apart along the Y direction on the second main portion; a mounting groove 1123 is formed on the second main portion, and a first flow groove 1124 and a second flow groove 1125 are respectively formed on the two second extension portions; the mounting groove 1123, the first flow groove 1124 and the second flow groove 1125, together with the base plate 111, respectively enclose an installation cavity, a steam outlet 114 and a liquid inlet 115. The cover body 1121 also includes a third extension portion, which is located on the same side or adjacent to the second extension portion, and a third flow groove 1126 is also formed on the third extension portion; the third flow groove 1126 and the base plate 111 enclose a vacuum filling port 116; the vacuum filling port 116 is disposed adjacent to the liquid inlet 115 and is located on the same side or adjacent to the liquid inlet 115. After completing the vacuuming and working fluid filling by connecting the four-way valve to the vacuum filling port 116, the vacuum filling port 116 is sealed; the working fluid is preferably water, methanol, ethanol or electronic fluorinated liquid (such as FC-72, HFE-7100, etc.).

[0071] In another specific embodiment, the base plate 111 and Figure 3 The cover 112 in the middle has a symmetrical structure, which will not be described in detail here.

[0072] In another specific embodiment of the present invention, by Figure 4 As shown, the end face of the branch 1212 of the capillary wick 121 near the steam outlet 114 (i.e., the first flow channel 1124) facing away from the main body 1211 along the Y direction is flush with the side wall of the first flow channel 1124 facing the second flow channel 1125. This arrangement prevents the branch 1212 from blocking the steam outlet 114, which is beneficial for steam to enter the steam pipeline 2 smoothly. In addition, the end face of the branch 1212 of the capillary wick 121 near the steam outlet 114 facing away from the main body 1211 along the Y direction abuts against the side wall of the mounting groove 1123.

[0073] In another embodiment of the present invention, by Figure 6 and Figure 7As shown, the capillary wick unit 12 also includes a first wire mesh structure 122 and a second wire mesh structure 123 located on both sides of the capillary wick 121 along the Z-direction and conformally adapted to the mounting cavity (i.e., mounting groove 1123), forming a "sandwich" structure. The first wire mesh structure 122 is attached to the base plate 111, and the second wire mesh structure 123 is attached to the bottom of the mounting groove 1123 on the cover 112. The first wire mesh structure 122 and the second wire mesh structure 123 are used to provide support for the capillary wick 121 from both sides, thereby improving the mechanical strength and service life of the capillary wick 121. Furthermore, the first wire mesh structure 122 is a porous structure formed by wire mesh, with a large effective pore size and a porosity of over 75%, which can significantly reduce the flow resistance of liquid entering the base plate 111, thereby improving heat transfer performance. In this embodiment, capillary force is used to draw the liquid working fluid into the main body 1211 of the main capillary core 121 and the first metal wire mesh structure 122 for heat exchange. In addition, after the liquid is saturated, the second metal wire mesh structure 123 and the branch 1212 can also form a vapor-liquid isolation zone to prevent vapor from flowing back into the liquid pipeline 4, thereby improving the accuracy of gas-liquid separation.

[0074] In one specific embodiment, the overall thickness of the evaporator 1 does not exceed 1 mm. The overall thickness of the capillary wick 121, the first metal mesh structure 122, and the second metal mesh structure 123 is greater than the depth of the mounting cavity (i.e., the mounting groove 1123) along the Z direction; this arrangement can achieve an interference fit between the capillary wick unit 12 and the encapsulation shell 11, effectively preventing steam from crossing the second metal mesh structure 123 and entering the liquid pipeline 4 to form crosstalk.

[0075] Some embodiments of the present invention, Figure 6 The evaporator 1 shown is manufactured using a combination of integral sintering and diffusion welding, and is based on a manufacturing mold 10; wherein, the manufacturing mold 10 (made of...) Figure 13 (As shown) includes, from bottom to top, a mold base 101, a mold body 102, and a mold cap 103, as well as a locking element for locking and fixing the three together; the specific manufacturing steps include:

[0076] S1. Place the base plate 111, the first metal wire mesh structure 122 and the mold body 102 on the mold base 101 from bottom to top; fill the capillary core forming cavity 1021 on the mold body 102 with metal powder and pore-forming agent; wherein the mass fraction of the pore-forming agent is 10% to 20%, and the remainder is metal powder.

[0077] S2. After filling, cover the mold cap 103 and use locking components to lock the manufacturing mold 10 for pre-tightening and pressurization (the pressurization intensity is 50-100 MPa, which can enhance the contact between the metal powder and the pore-forming agent, thereby forming a larger sintering neck); then place the manufacturing mold 10 as a whole into a vacuum sintering furnace for sintering; nitrogen or argon is used for gas protection during the sintering process.

[0078] S3. After sintering, open the mold cover 103, take out the integrated sintered structure, and then put it into deionized water. After the pore-forming agent is completely dissolved (forming a porous structure), put it into a vacuum drying oven to dry.

[0079] S4. Place the second metal wire mesh structure 123 on the integrated sintered structure, then fasten the cover 112. Weld the second metal wire mesh structure 123 to the cover 112 using medium-frequency diffusion welding, and simultaneously complete the sealing connection between the bottom plate 111 and the edge of the cover 112; the evaporator 1 is now complete. The maximum welding temperature is 500–600℃, and the welding pressure is 100–200 MPa.

[0080] The purpose of adding a pore-forming agent is to increase the porosity and permeability of the capillary wick 121 and reduce the resistance to liquid flow. The pore-forming agent is Na2CO3 or NaCl particles with a particle size of tens of micrometers. A pore-forming agent content of 10% to 20% by mass can ensure a high porosity while preventing the mechanical strength of the capillary wick 121 from being reduced due to excessive pore-forming agent content.

[0081] In this embodiment, the mold cap 103 is provided with a contour pressing head adapted to the capillary core forming cavity 1021, and the mold base 101 is provided with a base plate positioning groove 1011 for positioning the base plate 111. This arrangement can ensure the pressure strength and the sintering accuracy of the base plate 111 with the first metal wire mesh structure 122 and the capillary core 121.

[0082] In traditional loop heat pipes, the capillary wick is a block structure that makes mechanical contact with the heat transfer base plate, meaning it is placed directly on the base plate. In this case, the contact thermal resistance between the capillary wick and the base plate is relatively high, making it difficult for heat to be quickly transferred to the liquid inside the capillary wick. This results in a high temperature on the heat transfer base plate and a slow start-up process. However, the evaporator 1, manufactured using a combination of integrated sintering and diffusion welding, achieves atomic-level contact between the cover 112, the second metal mesh structure 123, the first metal mesh structure 122, the capillary wick 121, and the base plate 111. This atomic-level contact significantly reduces the contact thermal resistance between the capillary wick 121, the first metal mesh structure 122, and the base plate 111, facilitating rapid heat transfer to the liquid inside the capillary wick 121, thereby reducing the temperature of the base plate 111 and the start-up time. Furthermore, the atomic-level contact between the cover 112 and the second metal mesh structure effectively prevents steam in the steam collection channel 113 from entering the liquid pipe 4, ensuring gas-liquid separation during the operation of the loop heat pipe structure.

[0083] Some embodiments of the present invention also disclose an electronic device, including a first component and at least one second component hinged to the first component; it also includes the aforementioned loop heat pipe structure; an evaporator is arranged in the first component as the hot end and abuts against a heat dissipation device disposed thereon, a flexible tube is located at the hinge, and a condenser is arranged in one of the second components as the cold end; or, an evaporator is arranged in one of the second components as the hot end and abuts against a heat dissipation device disposed thereon, a flexible tube is located at the hinge, and a condenser is arranged in the first component as the cold end; or, an evaporator is arranged in one of the second components as the hot end and abuts against a heat dissipation device disposed thereon, a flexible tube is located at the hinge, and a condenser is arranged in another second component as the cold end.

[0084] Depend on Figure 9 As shown, in a specific embodiment of the present invention, the electronic device is smart glasses 7. The first component is a frame 71, and the second component is a temple 72. The temple 72 is hinged to the end of the frame 71 via a hinge 73, allowing the temple 72 to be folded relative to the frame 71. In the loop heat pipe structure, the evaporator 1 is arranged within one of the temples 72 (the hot end) and abuts against the heat-dissipating device c mounted thereon. At least part of the flexible tube is located at the hinge. The condenser 3 is arranged within the frame 71 (the cold end). The vapor pipe 2 and liquid pipe 4 on one side of the flexible tube are encapsulated within the temple 72, and the vapor pipe 2 and liquid pipe 4 on the other side are encapsulated within the frame 71. The loop heat pipe structure can transfer the heat generated by the heat-dissipating device c within one temple 72 across regions and over long distances to the frame 71 and dissipate it into the external environment; it fully utilizes the surface area of ​​the smart glasses 7 for effective heat dissipation, resulting in good heat dissipation performance.

[0085] Preferably, the mounting plane of the evaporator 1 is parallel to the inner and outer walls of the mirror temple 72, and the mounting plane of the condenser 3 is parallel to the mounting plane of the mirror frame 71. This helps to reduce the space occupied and realize the development of the product towards miniaturization. In addition, the vacuum filling port 116 is set downwards. The liquid pipeline 4 and the steam pipeline 2 are in an L-shaped structure, and the liquid pipeline 4 is set parallel to the bottom of the steam pipeline 2. This setting can accelerate the liquid return by using its own gravity.

[0086] Depend on Figure 10 As shown, in another specific embodiment, the electronic device is still the smart glasses 7. In this case, both the steam pipe 2 and the liquid pipe 4 have two flexible tubes, corresponding to the positions of the two hinges 73. The evaporator 1 is arranged inside one of the temples 72 (the hot end) and contacts the heat-dissipating device c mounted thereon. The condenser 3 is arranged inside the other temple 72 (the cold end). The loop heat pipe structure can transfer the heat generated by the heat-dissipating device c in one temple 72 across regions and over long distances to the other temple 72 and dissipate it into the external environment.

[0087] Preferably, the mounting plane of the evaporator 1 is parallel to the inner and outer walls of one of the mirror legs 72, and the mounting plane of the condenser 3 is parallel to the inner and outer walls of the other mirror leg 72; the liquid pipeline 4 and the steam pipeline 2 are U-shaped, and the liquid pipeline 4 is arranged parallel to the bottom of the steam pipeline 2. This arrangement can accelerate the liquid return by means of its own gravity.

[0088] In another specific embodiment (not shown in the figure), the electronic device is smart glasses. In this embodiment, the evaporator in the loop heat pipe structure is arranged within one of the frames (the hot end) and contacts the device to be cooled. The flexible tube is located at the hinge, and the condenser is arranged within the temple (the cold end). The loop heat pipe structure can transfer heat generated by the device to be cooled across regions and over long distances to a temple and dissipate it into the external environment. It fully utilizes the surface area of ​​the smart glasses for effective heat dissipation, resulting in good heat dissipation performance.

[0089] Depend on Figure 11As shown, in another specific embodiment of the present invention, the electronic device is a foldable phone 8, the first component is a main body 81, and the second component is a foldable body 82. In the loop heat pipe structure, the evaporator 1 is arranged within one of the main bodies 81 (the hot end) and abuts against the heat-dissipating device c disposed thereon. The flexible tube is located at the hinge, and the condenser 3 is arranged within the foldable body 82 (the cold end). The steam pipe 2 and liquid pipe 4 on one side of the flexible tube are encapsulated within the main body 81, and the steam pipe 2 and liquid pipe 4 on the other side are encapsulated within the foldable body 82. The loop heat pipe structure can transfer the heat generated by the heat-dissipating device c within the main body 81 across regions and over long distances to the foldable body 82 and dissipate it into the external environment; it fully utilizes the surface area of ​​the foldable phone 8 itself for effective heat dissipation, resulting in good heat dissipation performance. Similarly, if the heat-dissipating device c is located within the foldable body 82, the evaporator 1 and condenser 3 can be interchanged, which will not be elaborated here.

[0090] Depend on Figure 12 As shown, in another specific embodiment of the present invention, the electronic device is a laptop computer 9, the first component is the computer body 91, and the second component is the computer display unit 92. In the loop heat pipe structure, the evaporator 1 is arranged within one of the computer body parts 91 (the hot end) and abuts against the heat-dissipating device c disposed thereon. The flexible tube is located at the hinge, and the condenser 3 is arranged within the computer display unit 92 (the cold end). The vapor pipe 2 and liquid pipe 4 on one side of the flexible tube are encapsulated within the computer body 91, and the vapor pipe 2 and liquid pipe 4 on the other side are encapsulated within the computer display unit 92. The loop heat pipe structure can transfer the heat generated by the heat-dissipating device c within the computer body 91 across regions and over long distances to the computer display unit 92 and dissipate it into the external environment; it fully utilizes the surface area of ​​the computer body 91 itself for effective heat dissipation, resulting in good heat dissipation performance. Similarly, if the heat-dissipating device c is located within the computer display unit 92, the evaporator 1 and condenser 3 can be interchanged, which will not be elaborated here. In this embodiment, since the laptop computer 9 is a large-size electronic device, the condenser 3 preferably has a serpentine tube 31 structure.

[0091] In summary, the flexible tube arrangement allows electronic devices using loop heat pipe structures to fully utilize their own surface area for effective heat dissipation, resulting in good heat dissipation performance.

[0092] In summary, this invention facilitates the shortening of pipeline layout length, reduces space and weight occupation, and enables efficient heat transfer across regions and over long distances.

[0093] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A loop heat pipe structure, comprising an evaporator, a vapor pipe, a condenser, and a liquid pipe connected in sequence; characterized in that, The evaporator includes a housing and a capillary wick unit disposed within the housing; the housing is formed along the Y direction on the side facing the condenser with a steam outlet for connecting to one end of the steam pipeline and a liquid inlet for connecting to one end of the liquid pipeline. The capillary core unit includes a capillary core, which includes a main body extending along the X direction and a plurality of branch portions spaced apart along the X direction on the main body. The main body corresponds to the liquid inlet position. The branch portions extend along a direction forming a preset angle with the X direction, and from the side where the steam outlet is located to the opposite side, the extension length of the branch portions gradually increases to reserve a steam gathering channel communicating with the steam outlet. At least a portion of the steam pipeline and at least a portion of the liquid pipeline are respectively configured as flexible pipes; The encapsulation shell includes a base plate and a cover that are fastened together along the Z direction; the capillary core unit also includes a first metal mesh structure and a second metal mesh structure located on both sides of the capillary core along the Z direction and conformally adapted to the mounting cavity; the first metal mesh structure is attached to the base plate, and the second metal mesh structure is attached to the cover.

2. The loop heat pipe structure according to claim 1, characterized in that, An elastic skeleton is fitted onto the flexible tube.

3. The loop heat pipe structure according to claim 1, characterized in that, The condenser includes a serpentine tube, the two ends of which are respectively connected to the steam pipeline and the liquid pipeline; Alternatively, the condenser includes a condensing shell with a serpentine or U-shaped channel formed inside. The condensing shell has a steam inlet and a liquid outlet spaced along the Y direction on the side facing the evaporator, corresponding to the two ends of the serpentine or U-shaped channel. The other end of the steam pipe is connected to the steam inlet, and the other end of the liquid pipe is connected to the liquid outlet.

4. The loop heat pipe structure according to claim 1, characterized in that, The two ends of the steam pipeline are welded to the steam inlet and the steam outlet, respectively, or are sealed and connected via adapters; the two ends of the liquid pipeline are welded to the liquid inlet and the liquid outlet, or are sealed and connected via adapters.

5. The loop heat pipe structure according to claim 1, characterized in that, The cover includes a cover body and an edge portion connected together; The edge portion is fitted and sealed to the base plate, and the base plate and the cover are fastened together to form a connected mounting cavity, the steam outlet and the liquid inlet; the capillary core unit is disposed in the mounting cavity.

6. The loop heat pipe structure according to claim 5, characterized in that, The cover body is formed with an installation groove and two first and second flow grooves that are on the same side and spaced apart along the Y direction; the installation groove, the first flow groove and the second flow groove, together with the base plate, respectively enclose the installation cavity, the steam outlet and the liquid inlet.

7. The loop heat pipe structure according to claim 6, characterized in that, The cover body is also formed with a third flow groove; the third flow groove and the bottom plate surround a vacuum filling port; the vacuum filling port is located near the liquid inlet and is located on the same side or adjacent to each other.

8. The loop heat pipe structure according to claim 1, characterized in that, The end face of the branch near the steam outlet along the Y direction and away from the main body is flush with the inner wall of the side of the steam outlet facing the liquid inlet.

9. The loop heat pipe structure according to claim 5, characterized in that, The first metal wire mesh structure, the capillary core, and the base plate are an integrated sintered structure.

10. The loop heat pipe structure according to claim 5, characterized in that, The overall thickness of the capillary core unit is greater than the depth of the mounting cavity along the Z direction.

11. The loop heat pipe structure according to claim 10, characterized in that, The evaporator is manufactured based on a manufacturing mold; the manufacturing mold includes, from bottom to top, a mold base, a mold body, and a mold cap, as well as a locking element for locking and fixing the three together; the manufacturing steps include: S1. Place the base plate, the first metal wire mesh structure, and the mold body onto the mold base in sequence from bottom to top; fill the capillary core forming cavity on the mold body with metal powder and a pore-forming agent; wherein the mass fraction of the pore-forming agent is 10%~20%; S2. After filling, cover the mold cap and use the locking device to lock the manufacturing mold for pre-tightening and pressurization; then place the entire manufacturing mold into a vacuum sintering furnace for sintering; nitrogen or argon is used for gas protection during the sintering process. S3. After sintering, open the mold cover, take out the integrated sintered structure, and then put it into deionized water. After the pore-forming agent is completely dissolved, put it into a vacuum drying oven to dry. S4. Place the second metal wire mesh structure on the integrated sintered structure, then fasten the cover, and weld the second metal wire mesh structure to the cover using a medium-frequency diffusion welding method, while simultaneously completing the sealing connection between the base plate and the edge of the cover; the evaporator is now complete.

12. The loop heat pipe structure according to claim 11, characterized in that, The pore-forming agent is Na2CO3 or NaCl particles.

13. The loop heat pipe structure according to claim 11, characterized in that, The mold cover is provided with a contour pressing head that matches the capillary core forming cavity, and the mold base is provided with a base plate positioning groove for positioning the base plate.

14. An electronic device comprising a first component and at least one second component hinged to the first component; characterized in that, It also includes the loop heat pipe structure as described in any one of claims 1-13; The evaporator is arranged in the first component, which is the hot end, and abuts against the heat dissipation device disposed thereon. The flexible tube is located at the hinge. The condenser is arranged in one of the second components, which is the cold end. Alternatively, the evaporator is arranged within one of the second components, which serves as the hot end, and abuts against the heat dissipation device disposed thereon, with the flexible tube located at the hinge, and the condenser arranged within the first component, which serves as the cold end. Alternatively, the evaporator is arranged within one of the second components, which serves as the hot end, and abuts against the heat dissipation device disposed thereon, with the flexible tube located at the hinge, and the condenser is arranged within the other of the second components, which serves as the cold end.

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