KR101164611B1 - Method for manufacturing evaporator for looped heat pipe system - Google Patents

Abstract

The present invention relates to a method of manufacturing an evaporator for a loop heat pipe (LHP) system, comprising: a wick forming step of forming a plurality of porous wicks; Heat generating fin forming step of forming a plurality of heat transfer fins having a wick coupling portion that can be coupled to any one of the plurality of wicks: forming a unit assembly by placing the one wick in the wick coupling portion of the one heat transfer pin Forming a unit binder; Unit bonding step of coupling the contact surface of the wick and the heating fins by applying at least one of heat and pressure to the unit assembly: the unit assemblies are arranged in a transverse direction so that each lower side thereof is on a plane A conjugate structure forming step of forming a conjugate structure of the; A combination structure coupling step of coupling the unit assemblies to each other by applying at least one of heat and pressure to the assembly structure; And arranging the assembly structure on the upper side of the plate-shaped heat transfer plate, and then applying heat or heat to the heat transfer plate coupling step of coupling the mutual contact surfaces of the assembly structure and the heat transfer plate.

Description

Method for manufacturing evaporator for loop heat pipe system {Method for manufacturing evaporator for looped heat pipe system}

The present invention relates to a method for manufacturing an evaporator which forms a loop heat pipe system together with a condenser, a gas transfer pipe, and a liquid transfer pipe. In particular, a heat transfer plate is manufactured after a heat transfer fin coupled to a wick is formed as a single member. The present invention relates to a method of manufacturing an evaporator for a loop type heat pipe system capable of manufacturing wicks and heating fins having various shapes and sizes, as well as minimizing contact thermal resistance between the two.

Electronic components such as CPUs and semiconductor chips used in various electronic devices such as computers generate a lot of heat during operation. Since such electronic components are usually designed to function properly at room temperature, it is necessary to effectively cool the heat generated during operation.

Several attempts have been made to cool electronic components, one of which is the phase change heat transport system. A recent example of such a phase change heat transfer system is a looped heat pipe (LHP) system.

1 conceptually illustrates a conventional looped heatpipe system 110. The loop heat pipe system 110 includes a condenser 112, an evaporator 114, and a vapor line 116 and a liquid line 118 connecting them. A working fluid is injected into the loop heat pipe system. The loop type heat pipe system 110 is provided with a porous wick only inside the evaporator 114, unlike a heat pipe having a normal cylindrical shape.

The basic principle of the operation of the loop heat pipe system 110 is as follows.

First, an evaporator in contact with an electronic component (not shown) that is a heat source is heated. When the evaporator 114 is heated, the working fluid that has permeated the internal wick phase changes into gas.

At this time, the generated gas is moved to the condenser 112 along the steam line 116 connected to one side of the evaporator 114. The migrated gas then releases heat and liquefies as it passes through the condenser 112. The liquefied working fluid is moved back to the evaporator 114 along the liquid line 118 on one side of the condenser 112. This process is repeated in cycles to cool the electronic components that are heat sources.

On the other hand, total heat resistance must be lowered for high performance and miniaturization of the loop type heat pipe system. When the heat resistance decreases, the heat source, that is, the electronic component, can be operated at a low temperature.

In order to reduce the total heat resistance of the system, several factors must be taken into account, but the most direct effect is due to the thermal contact resistance between the wick in the evaporator and the base contact surface of the evaporator. Thermal contact resistance shall not consider only the size of the apparent area of the contacting surface of two objects where heat transfer occurs. That is, even though the physical contact area is the same, the actual contact point area where the two objects actually touch may vary according to the state of the contact surface, so the actual contact point area considering the state of the contact surface should be considered. Heat transfer between the wick and the base contact surface of the evaporator is caused by conduction through the actual contact surface and through the void between the contact surface. Most of the resistance is created by the gap between the wick and the base contact surface of the evaporator. Increasing the area of the contact point of the wick and the base of the evaporator can reduce the thermal contact resistance. In other words, the thermal contact thermal resistance is related to the thermal resistance generated when the metal surface is in contact with another metal surface, and has a great difference depending on the area of the surface of the contact point.

Generally, in order to increase the actual contact area, the surface is polished and contacted, and in some cases, thermal grease is applied.

The thermal contact resistance of the loop heat pipe system is closely related to the state of the heating interface of the evaporator and the contact interface of the sintered wick, and is a very important factor in the phase change of the working fluid in the liquid state into the vapor state by receiving heat. to be.

Even if the sintering wick and the base serving as the hot plate are in contact with the surface over a large area, if the contact state between the contact surfaces in the microscopic view is not good, heat transfer to the sintering wick will not be performed smoothly. The temperature of the base, which serves as a hot plate of the evaporator, is then raised to increase the temperature of the steam to the operating level of the system. Since steam acts as a medium to transfer heat to the condenser, operating at high steam temperatures will result in increased total heat resistance of the loop heat pipe system.

Therefore, in the evaporator, since the actual contact area between the sinter wick provided inside the evaporator and the internal structure of the sinter wick and the evaporator is increased, the value of the thermal contact resistance is reduced, resulting in cooling the electronic components to a low temperature. It will be the key.

By the way, in the evaporator, the prior art which attempted to increase the contact area of the structure and the wick inside is disclosed by patent application 10-2006-0024388. However, the prior art, referring to the published patent publication, although there are structural considerations for increasing the contact area between the protrusions 120 and the wick 410, which are the structures inside the evaporator, there are limitations in the shape implementation of the structures. And, there is a disadvantage that the heat transfer is not made effectively because the state of the contact surface is not good.

That is, in the case of the prior art, referring to FIGS. 1, 5, and 6 (represented by FIGS. 2, 3, and 4 of the present disclosure, respectively) of the patent publication, the area of the portion where the wick and the protrusion contact each other is simply Although it appears to be relatively wider than its predecessor, the actual contact surface between the wick 410 and the contact surface of the protrusion 120 is poor because in practice the wick 410 is simply inserted and coupled between the protrusions 120. Can not do it. In other words, the contact point is not most of the contact surface, there is a disadvantage that the heat transfer from the protrusion 120 to the wick 410 does not occur effectively.

In the related art, referring to FIG. 5, which is illustrated as a contact resistance between an interface and a wick, the contact surface of the protrusion 120 and the wick 410 is enlarged by an electron microscope or the like, between the protrusion 120 and the wick 410. It is found that most of them are coupled by point contact, and thus the temperature decreases at the contact interface.

 Therefore, in case of an evaporator operating under the same heat load, the temperature of the heating surface may vary according to the value of the thermal contact resistance of the evaporator operating at the same steam temperature. If the value of the thermal contact resistance is high, the temperature of the heating interface is high, If the value of the contact resistance is low, the temperature of the heating interface is low.

In the prior art, since the protrusions 120 are integrally formed on the inner surface of the heat generating contact portion 110 which is a metal plate, there are various limitations in controlling the shape of the protrusions and the roughness of the surface, and the protrusions 120 Since the plurality of wicks 410 inserted into the corresponding ones also correspond to the shape of the protrusion 120, there are disadvantages in that the selection of the material or the shape is limited. This limitation is a major reason making it difficult to improve the condition of the connection surface.

That is, in the prior art, since the protrusions 120 are integrated with the heat generating source contact unit 110 in the evaporator, and the wick inserted in the protrusions has a corresponding shape, there is a limit to implementing various shapes. In addition, there is a problem in that the contact interface between the protrusion and the wick is not good and the contact heat resistance is high, so that the cooling of the electronic component is not effectively performed.

The present invention has been proposed to solve the above problems, in the method for manufacturing an evaporator for a loop bottom pipe system, it is possible to implement a variety of materials and shapes of the wick, as well as the heating fins and the heating fins and wicks It is an object of the present invention to provide a manufacturing method capable of improving the contact state therebetween.

The method of manufacturing an evaporator for a loop heat pipe (LHP) system of the present invention includes: a wick forming step of forming a plurality of porous wicks; Heat generating fin forming step of forming a plurality of heat transfer fins having a wick coupling portion that can be coupled to any one of the plurality of wicks: forming a unit assembly by placing the one wick in the wick coupling portion of the one heat transfer pin Forming a unit binder; Unit bonding step of coupling the contact surface of the wick and the heating fins by applying at least one of heat and pressure to the unit assembly: the unit assemblies are arranged in a transverse direction so that each lower side thereof is on a plane A conjugate structure forming step of forming a conjugate structure of the; A combination structure coupling step of coupling the unit assemblies to each other by applying at least one of heat and pressure to the assembly structure; And arranging the assembly structure on the upper side of the plate-shaped heat transfer plate, and then applying heat or heat to the heat transfer plate coupling step of coupling the mutual contact surfaces of the assembly structure and the heat transfer plate.

On the other hand, the wick forming step, using at least one of the metal powder, non-metal powder, metal fiber and non-metal fiber as a material, it is preferable to form a desired shape by applying at least one of heat and pressure.

In the wick forming step, at least one of the thermoplastic polymer and the organic solvent material may be mixed to form a desired shape by applying at least one of heat and pressure.

In addition, the wick forming step, after the wick is formed in a desired shape, it is preferable to remove the thermoplastic polymer or organic solvent material mixed by any one of solvent extraction and pyrolysis.

On the other hand, in the unit binder forming step, before the wick is inserted into the wick coupling portion of the heating fin, the bonding promoter of any one of the metal powder and the bonding material is located on at least a portion of the contact surface of the wick and the heating fin. It is preferable to further include a bonding catalyst insertion step to make.,

On the other hand, the assembly structure forming step, it is preferable to further include the step of disposing at least one of the intermediate wick and the spacer between the adjacent unit assemblies.

In addition, in the forming of the assembly structure, it is preferable to further include the step of contracting the diameter of the voids present in the interior of the wick by applying pressure to the assembly structure in the transverse direction.

On the other hand, in the step of forming the assembly structure, it is preferable to further include a step of applying a pressure means to shrink the diameter of the pores present in the interior of the wick by applying pressure on both sides of the assembly structure.

In addition, after the wick forming step, the heat generating fin forming step, the unit binder forming step and the binder structure forming step is performed, the unit binder combining step, the binder structure coupling step and the heating plate coupling step is performed simultaneously in one step, Alternatively, the heating plate coupling step may be performed after the unit binder coupling step and the coupling structure coupling step are performed at the same time, or after the coupling unit coupling step is performed, the coupling structure coupling step and the heating plate coupling step are preferably performed.

According to the method for manufacturing an evaporator for a loop type heat pipe system according to the present invention, since the wick and the heating fins are first manufactured, a plurality of them are arranged and then attached to the heat transfer plate, which is a metal plate, to manufacture the evaporator, thus the complicated shape of the heating fins is obtained. Or it is easy to implement the shape according to the user's needs, and it is possible to improve the contact state between the heating fin and the wick, thereby increasing the heating area and the steam generating area and minimizing the contact thermal resistance between the heating fin and the wick. The effect is possible.

The present invention relates to a method for manufacturing an evaporator which forms a loop heat pipe system together with a condenser, a gas conveying tube and a liquid conveying tube. Description of the operation of the loop heat pipe system is applied to the above-described in the background section.

First, the configuration of the evaporator 1 manufactured by one embodiment according to the evaporator manufacturing method for a loop heat pipe system of the present invention will be described with reference to FIG. 6 is a schematic exploded perspective view of the evaporator 1.

The evaporator 1 is configured to include a wick 10, a heat transfer fin 20, a heat transfer plate 50, and a cover member 60.

The wick 10 is porous, and referring to FIG. 8, the shape has the shape of a thin plate.

A plurality of heat transfer fins 20 are provided, and each heat transfer fin 20 is provided with a wick coupling portion 22 to which one wick 10 may be coupled (see FIG. 9). One wick 10 and one heating fin 20 are combined to form a unit assembly 30 (see FIG. 10). The unit assemblies 30 are laterally arranged to form the assembly structure 40 (FIG. 11). The heat transfer plate 50 is coupled to the lower end of the assembly structure 40.

The heat transfer plate 50 is made of a metal material, and its lower surface is a portion in contact with the heat source, and receives heat from the heat source. A heat source is an electronic component that generates heat during operation, for example, a computer central processing unit (CPU), a graphics card chipset, and the like.

The cover member 60 is coupled to the upper portion of the heat transfer plate 50. The cover member 60 forms an inner space together with the heat transfer plate 50, and the assembly structure 40 is positioned in the inner space. One side of the cover member 60 is formed with a steam line coupling hole 62 to which the steam line is coupled, and a liquid line coupling hole 64 to which the liquid line is coupled is formed at one side of the upper surface.

On the other hand, in the assembly structure 40, the steam generated in the wick 10 is coupled between the wick 10 and the projections (26, 28) of the heat transfer fin 20 in a state where the vapor passage is secured. Therefore, it can escape to the steam line coupling hole 62 of the cover member 60.

The operation of the evaporator 1 of this configuration will be described. The working fluid in the liquid state introduced into the evaporator 1 through the liquid line coupling hole 64 is permeated into numerous pores formed in the porous wick 10. Heat of the heat source transferred to the heat transfer fins 20 through the heat transfer plate 50 is transferred to the wick 10 again to change the working fluid in the liquid phase into gas. The working fluid changed into gas exits the evaporator through the vapor line coupling hole 62 through the vapor passage space.

Hereinafter, a method of manufacturing an evaporator for a loop type heat pipe system having the configuration as described above will be described with reference to FIGS. 7 to 12 as one embodiment according to the present invention.

The method of manufacturing an evaporator for a loop heat pipe system according to the present embodiment includes a wick forming step (S1), a heating fin forming step (S2), a unit binder forming step (S3), a unit binder combining step (S4), and a conjugate structure forming step. (S5), the assembly structure coupling step (S6) and the heating plate coupling step (S7) is configured.

The wick forming step (S1) is a step of forming a plurality of porous wicks 10.

The wick 10 is a porous structure in which numerous voids exist. The working fluid is infiltrated into the voids, and is phase-changed into water vapor by heat received from the heat transfer fins 20. In the case of this embodiment, the shape of the wick 10 is a shape of a thin square plate, as shown in FIG. However, the shape of the wick 10 may be variously modified as necessary.

The wick 10 is selected from at least one of metal powder, nonmetal powder, metal fiber and nonmetal fiber as a material, and is formed into a desired shape by applying at least one of heat and pressure to the selected material. That is, heat is applied to the material, pressure is applied, or heat and pressure are applied together to form a desired shape.

The wick formation step S1 may be referred to as a pre-formming process.

First, the step of forming the wick using the metal powder and the metal fiber will be described. The wick forming step (S1) is a step for obtaining a porous member, and among metal powder particles and metal wires such as copper, brass, bronze, nickel, titanium, aluminum, and stainless steel, etc. It is carried out using at least one as the material. It is common to select one type of metal powder and metal fiber, but if necessary, two or more metal powders may be selected, or a metal powder and a metal fiber may be mixed and selected.

At least one of heat and pressure is applied to the selected material to form a desired shape. That is, the raw metal or the raw metal fiber is filled into a jig, a frame, or the like, and then heat is applied, pressure is applied, or heat and pressure are simultaneously applied to form a desired shape. In the case of applying heat, the raw metal may be applied at a sintering temperature at which the raw metal may be sintered, or may be heated to a presintering temperature lower than the sintering temperature. The presintering temperature is a temperature in the range of approximately 80% to 90% of the sintering temperature at which the raw metal is sintered.

In addition, in order to form a desired shape by applying pressure to the raw material metal, a method of injection, or a method of applying pressure after filling a jig or a mold is used.

On the other hand, when a metal powder or a metal fiber is used as a wick material, the wick becomes a porous sintered body by sintering. However, the wick is sintered may be made in the wick forming step (S1), it may be made by heating to the sintering temperature during any one of the unit binder bonding step, the assembly structure bonding step or the heating plate bonding step to be carried out. .

In other words, if sintering has already been performed in the wick forming step, heat is applied in the subsequent step, in which heat is applied at a temperature lower than the sintering temperature in order to improve the bonding state of the contact surface. However, if the wick is not sintered in the wick forming step, the sintering should be performed in a subsequent step, so that heat is applied to the sintering temperature in any one of the subsequent bonding steps, wherein the contact surface Will also be in good condition.

On the other hand, the wick 10 may be formed in a desired shape by selecting at least one of the non-metal powder and the non-metal fiber as a material, and applying at least one of heat and pressure to the selected material.

Examples of the base metal include powder of alumina (Al 2 O 3), which is a ceramic series, and active carbon and carbon graphite, which are graphite series. Fill non-metal powder or non-metal fiber into jig or shape frame and apply heat, pressure or heat and pressure at the same time to make shape.

However, when the non-metal material is selected as the material of the wick, in the unit bonding step in which the wick and the heating fin are combined, the wick and the metal heating fins of the non-metal material may be a desired bond by heat. And thus increase the mutual contact point area by pressure.

On the other hand, in the present embodiment, the wick forming step (S1) is configured to mix at least one of the thermoplastic polymer and the organic solvent material to form a desired shape by applying at least one of heat and pressure. Thermoplastic polymers are adhesive polymer materials such as polyethylene (PE), polypropylene (PP), acrylic resins, and styrene resins. These thermoplastic polymers promote adhesion to powders of the required shape before sintering, Used to minimize breakage, volume change, etc.

A wick is formed through injection or pressurization after mixing an organic solvent material, which is a polymer or a sublimable material, with a material such as metal powder and metal fiber.

The organic solvent material, which is a sublimable material, is in a solid state at room temperature and undergoes a phase change from a solid state to a gas state as it is heated to a predetermined temperature. Organic solvent materials include substances that have sublimation properties such as naphthalene. Either ether or alcohol, or a mixture of two may be used.

Such an organic solvent material is used for the manufacture of a complex shape that is difficult to implement, and when the organic solvent material is inserted before the molding, the place where the organic solvent material is inserted during the sintering molding is sublimed, thereby making it possible to produce the required shape.

In addition, when the thermoplastic polymer and the organic solvent material are mixed with the material metal in the wick forming step (S1), the thermoplastic polymer or the organic solvent material, which is mixed with one of solvent extraction and pyrolysis, is formed after the wick is formed in a desired shape. You can also remove it. In subsequent loop heat pipe operation, the residues of thermoplastic polymers or organic solvents may react with the working fluid, causing corrosion, fouling, and non-condensible gases. Should be removed.

The heat transfer fin forming step (S2) is a step of forming a plurality of heat transfer fins 20 having a wick coupling portion 22 to which one wick 10 may be coupled (see FIG. 9). The heat transfer fin 20 processes a metal having a relatively high thermal conductivity by using a cutter such as milling. However, the processing method can be variously applied. The heat transfer fin 20 serves to transfer heat back from the heat transfer plate 50 to the wick 10.

The heat transfer fin 20 is composed of a lower member 24 and a plurality of protrusions 26 and 28. The upper surface of the lower member 24 is in contact with the lower side of the wick 10, and the inner surfaces of the protrusions 26 and 28 are in contact with both sides of the wick.

The protrusions 26 located on one side and the protrusions 28 located on the other side protrude upward from both ends of the lower member 24, respectively. The protrusions 26 and 28 are spaced apart from each other, and the spaces spaced apart from each other become a passage of steam generated in the wick 10.

Since the heat transfer fins 20 are made of different members and are also separate from the heat transfer plate 50, they are easy to process relatively complicated shapes including the protrusions 26 and 28 and the wick coupling portion 22. In addition, it is easy to adjust the roughness of the machined surface to the desired degree.

On the other hand, in performing the wick forming step (S1) and the heat transfer fin forming step (S2), any step may be performed first.

Next, the unit assembly forming step (S3) is performed.

In the unit assembly forming step (S3), the one wick 10 is inserted into the wick coupling portion 22 of the one heating fin 20 to form the unit assembly 30 as shown in FIG. 10. to be.

On the other hand, in the present embodiment, the unit assembly forming step (S3), before the wick 10 is inserted into the wick coupling portion 22 of the heat transfer fins 20, the coupling promoter, the wick 10 and the heat transfer It is configured to further include a coupling promoter insertion step to be located at least a portion of the contact surface of the pin (20).

The coupling promoter insertion step is a step of placing the coupling promoter on the surface that the wick 10 and the heat transfer fins 20 are in contact with each other. Bonding promoter, by the heat or pressure applied in the process of the subsequent unit binder bonding step (S4), to help the wick and the heat-contacting surface of the heating pin is made of a more solid metal bond.

As the bonding promoter, any one of a metal powder and a joining material is selected. However, in the case where the bonding promoter is inserted, the heat of the heat and the output of the unit binder must be applied to the unit binder in a subsequent unit binder bonding step.

First, the case where the bond family is a metal powder will be described.

Before inserting the wick 10 between the heating fins 20, the metal powder is sprayed between the protrusions 26 and 28 and the upper surface of the lower member 24, and then the wick 10 is projected to the protrusion 26. 28)) between them. Since the size of the metal powder is quite small as a micro unit, when the wick 10 is inserted after sprinkling the metal powder on the corresponding surface of the heating fin 20, the surface of the wick and the heating fin 20 is in contact with each other. The metal powder can be placed. Alternatively, the metal powder may be sprinkled on the surface of the wick 10 and then inserted into the heat transfer fin 20.

11 illustrates an exaggerated view in which the metal powder 11 is positioned on the surface where the wick 10 and the heating fin 20 are in contact with each other.

On the other hand, the metal kind of the metal powder may be the same as that of a molding material, or another kind of metal powder may be used.

In addition, a joining material may be used as the bonding promoter. Soldering material shall contain solder material.

The wick 10 and the heating fins 20 are further provided with a step of inserting a brazing material or a solder material on the surface. According to the melting point of the base material of the wick 10 and the heat transfer fin 20 is inserted and soldered. For example, in the case of the wick 20 and the heat-transfer fin 20 of the copper material, or in the case of the wick of the nickel material and the heat-transfer fin 20 of the copper material, Sn-Pb, Sn, Pb In the case of stainless wick and aluminum heating fins, materials such as silver lead, brass lead, silver lead, gold lead, platinum lead, aluminum lead and iron lead are used.

On the other hand, as the bonding promoter, a polymer contact agent may be used, and a thermoplastic polymer, polyethylene (PE), polypropylene (PP), acrylic resin, styrene resin, or the like, which is an adhesive polymer material, may be used.

 The unit bonding step (S4) is a step of coupling the contact surface of the wick 10 and the heat transfer fin 20 by applying at least one of heat and pressure to the unit assembly 30. Heat is applied to the unit assembly 30, or pressure is applied to both sides of the unit assembly 30 in the vertical direction, or by applying heat and pressure together to join the contact surface of the wick 10 and the heat transfer fins 20 in contact with each other. Step. On the other hand, in the case where the bonding unit inserting step is included in the unit assembly forming step (S3), the coupling of the mutual contact surface may be more robust.

The temperature of the heat to be applied is appropriately set depending on whether the material of the wick and the material of the wick are metal are sintered at this stage or at a later stage.

In the assembly structure forming step S5, a plurality of unit assemblies 30 are disposed in a transverse direction so that each of the lower side surfaces 29 is on one imaginary plane, and one assembly structure 40 is formed. Forming a step. By bringing the lower side 29 of each unit assembly 30 on an imaginary plane, it can be easily coupled to the flat upper surface of the heat transfer plate 50 to be described later.

Meanwhile, in the present embodiment, the assembly structure forming step S5 includes disposing the intermediate wick 12 between the unit assemblies 30 adjacent to each other. 12 illustrates an assembly structure 40 with an intermediate wick 12 disposed between the unit assemblies 30. By adding the intermediate wick 12, it is possible to increase the heat transfer area and the steam generation area.

In addition, a spacer may be disposed instead of the intermediate wick 12. 13 to 16, two embodiments of a binder structure in which spacers are disposed between unit assemblies are shown. The space between the unit assemblies secured by the spacers is used as a vapor passage to help the steam generated in the wick to be discharged to the outside more smoothly.

13 and 14, the spacer structure 14, which is shaped like a comb, is provided between the unit assemblies 30a in the assembly structure 40a illustrated in FIGS. 13 and 14. In this case, the heat transfer fin 20a to which the wick 10 is coupled is made of a considerably thinner thickness as compared with the previous embodiment. Since the heating fins 20a are individually processed, the lower member 24a and the protrusions 26a and 28a may be processed to a considerably thin thickness. The vapor passage 15 is secured between the unit assemblies 30a by the spacers 14.

15 and 16 show an assembly structure 40b having a spacer 16 of a different shape than the previous embodiment. Each portion of the heat transfer fin 20b, that is, the lower member 24b and the projections 26b and 28b, is thinner in thickness. The vapor passage 17 is secured between the unit assemblies 30b by the spacer 16.

On the other hand, to secure the vapor passage, it may be provided with a jig (not shown) having a similar shape to the spacer to serve as the spacer (14, 16). The jig is configured to be removed from the binder structure after the heat transfer plate bonding step S7 in which the binder structure is bonded to the heat transfer plate 50 is performed.

In addition, the assembly structure forming step (S5), by pressing the assembly structure 40 in the transverse direction, the direction in which the unit assemblies are arranged side by side to further shrink the diameter of the voids present in the interior of the wick (10) It may also include. In Fig. 17, the direction in which the force is applied is shown by an arrow.

In FIG. 18, it is illustrated that the length of the diameter of the gap 18 inside the wick 10 before being pressed is reduced to D1 by being pressed in the arrow direction at D0. The reduced voids are suited to the material of the wick, and remain reduced even when the pressure is removed. On the other hand, the wick 10 serves to transfer the working fluid to the evaporation interface by capillary pressure. At this time, if the diameter of the pores 18 is contracted, that is, the diameter is reduced, capillary pressure can be increased, and as a result, the working fluid can be quickly transferred to the interface where evaporation occurs to increase the cooling efficiency.

In addition, according to the embodiment, the assembly structure forming step (S5) may further comprise the step of providing a pressing means capable of applying pressure on both sides of the assembly structure (40). The pressurizing means is a means capable of contracting the diameter of the void existing in the wick 10 by applying pressure to the assembly structure 40 in both directions in the transverse direction.

The pressurizing means may be a rectangular frame 42 as illustrated in FIG. 19, or may be a clamp (not shown) capable of holding the assembly structure on both sides and screwing it together. In addition, after providing a through hole penetrating the assembly structure in the transverse direction, it is also possible to press the bolt screw therein to pressurize the assembly structure in the transverse direction.

The assembly structure coupling step (S6) is a step of coupling the unit assemblies 30 to each other by applying at least one of heat and pressure to the assembly structure 40. The heat is applied to the assembly structure 40, the pressure is applied in the transverse direction toward both sides of the assembly structure 40, or by applying heat and pressure together to combine the contact surface that the unit assembly 30 is in contact with each other.

The heat transfer plate coupling step (S7), as shown in Figure 12, after placing the assembly structure 40 on the upper surface of the plate-shaped heat transfer plate 50, by applying heat or heat and pressure, the assembly structure 40 And a step of coupling the mutual contact surfaces of the heat transfer plate 50.

At this time, according to the material and characteristics of the heat transfer plate 50 by applying a metal melting technique such as brazing and soldering, the assembly structure 40 and the heat transfer plate 50 can be combined.

After the heat transfer plate coupling step S7, the cover member 60 is coupled to the upper portion of the heat transfer plate 50 (see FIG. 6).

Meanwhile, the steps constituting the method for manufacturing the evaporator for the loop type heat pipe system of the present invention may be sequentially performed from step S1 to step S7 as described above. However, the present invention does not necessarily achieve the object if these steps are performed sequentially. That is, the wick forming step (S1), the heat transfer fin forming step (S2), the unit binder forming step (S3) and the binder structure forming step (S5) is first performed, then applying heat or pressure, or heat and pressure The unit binder bonding step (S4), the binder structure coupling step (S6) and the heat transfer plate coupling step (S7), which are made by adding together, may be simultaneously performed in one step.

 In addition, after the wick forming step (S1), the heating fin forming step (S2), the unit binder forming step (S3) and the binder structure forming step (S5) is performed, the unit binder coupling step (S4) and the binder structure coupling step ( After S6) is first performed in one process at the same time, the heat transfer plate coupling step S7 may be performed in a separate process.

 In addition, after the wick forming step (S1), the heating fin forming step (S2), the unit binder forming step (S3) and the binder structure forming step (S5) is performed, the unit binder bonding step (S4) is performed, and then The assembly structure coupling step (S6) and the heating plate coupling step (S7) may be performed simultaneously in one process.

The operation of the evaporator for the loop type heat pipe system manufactured by the above-described manufacturing process will be outlined.

The heat transfer plate 50 is coupled to an electronic component (not shown) that is a heat source to receive heat. The heat is transferred to the heat transfer fins 20, and then to the wick 10. The working fluid, which is present as a liquid in the interior voids of the wick 10 by the heat transferred to the porous wick 10, vaporizes and moves along the gas passage provided in the upper part of the wick 10. After that, it is moved to the condenser along the steam line. Heat is released again from the condenser and the liquefied working fluid is supplied to the wick 10 from the top through the liquid line coupling hole. As this process is circulated, the electronic parts are cooled.

Hereinafter, the effect of the manufacturing method of the evaporator for loop type heat pipe systems of the above-mentioned structure is demonstrated.

Characteristic of the configuration of the present invention, the heat transfer pin to which one of the wick is coupled to form a separate member, and the wick and the heat transfer pin combined to make a unit assembly, and then arranged a plurality of unit assemblies horizontally to form a combined structure Afterwards, the bonding structure is bonded to the heat transfer plate. As a result, it is possible not only to manufacture the wick and the heating fin having various shapes and sizes, but also to minimize the contact heat resistance between each other.

In other words, compared to the prior art that all the projections are integrally formed directly on the heat transfer plate, in the case of the present invention, since the heat transfer fin is processed into one separate member, processing of a complicated shape is relatively easy and considerably easy. It is also possible to process to have a thin thickness.

In the prior art, only the approach by tolerance and the like is possible to increase the contact force between the wick and the heating fin, and thus there is a limit to improving the adhesion between the wick and the heating fin. However, in the case of the present invention, the wick and the heating fin are limited. Because of the high adhesion of the fins, it is possible to activate steam generation and, consequently, to increase the performance of the evaporator.

In addition, in the case of the present invention, it is possible to easily adjust the thickness of the heat transfer fin, it is possible to find and apply the appropriate size of the vapor path. In addition, it is possible to manufacture the heating fins in accordance with the thickness of the wick, there is an advantage that it is easy to form the optimum structure by appropriately matching the steam generation area and the heat transfer area by applying a thin wick.

In addition, in the case of the present invention, the ease of processing described above can increase the heating area and the steam generating area, and minimizes the contact thermal resistance between the heat transfer fin and the wick provided with the projections, and thus, the loop heat pipe system. It is possible to reduce the total heat resistance.

In addition, when the wick is made of a metallic material, the wick and the heat-transfer fins, and the heat-transfer fins and the heat-transfer plate, are not simply in contact with each other at the mutually contacting surfaces, but rather by heat or pressure or heat and pressure. Because of this, the contact thermal resistance at the mating surface is reduced.

In the case of the prior art, after the sintered wick was manufactured, it was simply inserted into and joined between the protrusions of the base serving as a heat transfer plate by a physical method. Because of this, although the surface area of the contact surface between the sintered wick and the base appears to be increased in appearance, the bonding at the contact surface of the protrusion of the sintered wick and the base is mostly point contact, not surface contact, and thus the contact surface is not in good condition. In practice, the heat resistance at the contact surface is relatively high, which makes it difficult to transfer heat from the heat source to the sintered wick.

However, in the present invention, since the contact surface of the wick and the heating fin is not a simple physical bond, but is made of a metallic bond in which the metal is slightly melted to bond, the thermal resistance can be significantly lower than in the prior art. It is. This in turn makes it possible to operate the electrical component as a heat source at a low temperature.

On the other hand, in the case of the present invention, since the wick and the heating fins do not directly contact the heat source, it is possible to freely adjust the structure, width, thickness, and the like of the heating fins. That is, in the shape of the wick and the heat transfer fin, there is an advantage that it is easy to adjust the thickness and the total width, etc. so as to secure a wider heat transfer area and a steam generation area.

On the other hand, in order to combine the wick and the heating fins, when heat and pressure are applied at the same time, because the mutual coupling is made more closely, the thermal resistance at the contact surface is reduced.

In addition, due to the configuration for pressing the assembly structure in the transverse direction, the diameter of the voids in the interior of the wick is contracted, thereby increasing the capillary pressure has the advantage that the working fluid is well moved.

In addition, according to the present invention, the shape of the heat transfer fin can be variously formed, as well as providing a spacer disposed between the unit assembly. Due to this configuration, the shape design of each component can be freely modified and optimized so that the generated steam can smoothly escape to the outside of the evaporator.

21 to 23 show an embodiment in which the modified heating fin 20c is employed. Compared with the heat transfer fins 20 illustrated in FIG. 9, the heat transfer fins 20c of the present embodiment have one side protrusion removed and consist of only the other side protrusion 28c and the lower member 24c. 22 and 23 illustrate a unit assembly 30c in which the heating fins 20c and the wick 10 are coupled to each other, and an assembly structure 40c in which the unit assemblies 30c are disposed laterally. The manufacturing method for manufacturing the assembly structure 40c is applied as it is.

1 is a conceptual diagram of a prior art loop type heat pipe system 110,

2 to 4 are views for explaining the prior art,

5 is a view for explaining the state of the contact surface between the interface and the wick of FIGS.

6 is a schematic exploded perspective view of an evaporator manufactured by a method of manufacturing an evaporator for a loop type heat pipe system according to an embodiment of the present invention;

7 is a flowchart of a method of manufacturing an evaporator for a loop type heat pipe system according to an embodiment of the present invention;

8, 9, and 10 are views illustrating a wick, a heating fin, and a unit assembly, respectively.

FIG. 11 is a view in which the metal powder is located on the surface where the wick and the heating fin are in contact with each other.

12 is a view illustrating the assembly structure,

13 and 14 are cross-sectional views of the assembly structure of another embodiment, respectively,

15 and 16 are a cross-sectional view of the assembly structure and still another embodiment of the embodiment,

17 and 18 are views for explaining the lateral pressure is applied to the assembly structure,

19 is a view showing that a rectangular frame is provided as a pressing means in the assembly structure of another embodiment,

20 is a view illustrating a state in which the heat transfer plate is coupled to the assembly structure,

21 to 23 are views illustrating heat transfer fins, unit assemblies, and assembly structures of another embodiment, respectively.

Claims (9)

In the method of manufacturing an evaporator for a looped heat pipe (LHP) system, A wick forming step of forming a plurality of porous wicks; Heat generating fin forming step of forming a plurality of heat transfer fins having a wick coupling portion which can be coupled to any one of the plurality of wicks: A unit assembly forming step of forming a unit assembly by placing the one wick in a wick coupling portion of the one heat transfer fin; Unit bonding step of coupling the contact surface of the wick and the heating fins by applying at least one of heat and pressure to the unit assembly: An assembly structure forming step of arranging the unit assemblies in a transverse direction such that their respective lower sides are on one plane to form one assembly structure; A combination structure coupling step of coupling the unit assemblies to each other by applying at least one of heat and pressure to the assembly structure; And And arranging the assembly structure on the upper surface of the plate-shaped heat transfer plate, and then applying heat or heat and pressure to heat transfer plate joining step of joining the mutual contact surfaces of the assembly structure and the heat transfer plate. The wick forming step, A method of manufacturing an evaporator for a loop type heat pipe system, comprising at least one of a metal powder, a nonmetal powder, a metal fiber, and a nonmetal fiber to form a desired shape by applying at least one of heat and pressure. delete Claim 3 has been abandoned due to the setting registration fee. The method of claim 1, The wick forming step, A method of manufacturing an evaporator for a loop type heat pipe system, comprising mixing at least one of a thermoplastic polymer and an organic solvent to form a desired shape by applying at least one of heat and pressure. Claim 4 has been abandoned due to the setting registration fee. The method of claim 3, The wick forming step, After the wick is formed in a desired shape, a method of manufacturing an evaporator for a loop type heat pipe system, characterized in that the thermoplastic polymer or organic solvent material mixed by any one of solvent extraction and pyrolysis is removed. Claim 5 was abandoned upon payment of a set-up fee. The method of claim 1, The unit binder forming step, In the evaporator of the loop type heat pipe system characterized in that it further comprises a bonding catalyst inserting step of placing the bonding promoter of any one of the metal powder and the joining material on at least a portion of the contact surface of the wick and the heating fins. Manufacturing method. Claim 6 has been abandoned due to the setting registration fee. The method of claim 1, The assembly structure forming step, A method of manufacturing an evaporator for a loop type heat pipe system, further comprising disposing at least one of an intermediate wick and a spacer between the unit assemblies adjacent to each other. Claim 7 was abandoned upon payment of a set-up fee. The method of claim 1, In the assembly structure forming step, And compressing the assembly structure in a transverse direction to shrink the diameter of the voids present in the interior of the wick. Claim 8 was abandoned when the registration fee was paid. The method of claim 1, In the assembly structure forming step, And applying pressure on both sides of the assembly structure to provide pressurizing means for shrinking the diameter of the voids present in the wick. Claim 9 has been abandoned due to the setting registration fee. The method of claim 1, After the wick forming step, the heat generating fin forming step, the unit binder forming step and the binder structure forming step are performed, The unit binder coupling step, the assembly structure coupling step and the heating plate coupling step are carried out simultaneously as one step, or the unit plate coupling step and the coupling unit structure coupling step is performed at the same time, the heating plate coupling step is performed, or unit assembly coupling step After the is carried out, the assembly structure coupling step and the heat plate coupling step is characterized in that the manufacturing method of the evaporator for a loop type heat pipe system.

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