Heat exchanger, manufacturing method, and device

Abstract

The heat exchanger according to the present disclosure has an evaporator provided with an evaporation body that absorbs heat from the outside and evaporates a liquid-phase working fluid into a gas phase while moving the liquid-phase working fluid by capillary force, and condenses the gas-phase working fluid led out from the evaporator and returns the liquid-phase working fluid to the evaporator, the evaporator is provided with: a main body which is a plate-shaped member and in the plate surface of which a recess in which an evaporation body is provided is formed; and a cover body covering the recess of the main body and the evaporation body provided in the recess, the main body having a structural part in which the depth of the outer side of the recess is shallower than the depth of the center side of the recess, and the outer side of the evaporation body provided in the recess being sandwiched between the structural part and the cover body.

Description

Technical Field

[0001] The present disclosure relates to a heat exchanger, a manufacturing method, and an apparatus. Background Art

[0002] Patent Document 1 discloses a loop heat pipe that is provided inside an evaporation section, a condensation section, and a liquid return pipe, respectively, so as to efficiently cool a heat-generating component regardless of the installation angle, and has a wick that generates capillary force.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2008-215702 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] Furthermore, in recent years, with the miniaturization and high performance of devices such as electronic devices, the heat generation density of heat-generating bodies provided in the devices has increased. Also, for example, with the thinning of the device, a heat exchanger or the like that suppresses the size in the thickness direction while removing the heat flux from the heat-generating body is required.

[0008] Therefore, an object of the technology disclosed in the present specification is to manufacture a heat exchanger or the like that suppresses the size in the thickness direction.

[0009] Solutions to the Problems

[0010] Based on the above object, the technology disclosed in the present specification is a heat exchanger having an evaporator provided with an evaporation body that absorbs heat from the outside and evaporates into a gas phase while moving a liquid-phase working fluid by capillary force, and the heat exchanger condenses the gas-phase working fluid derived from the evaporator and returns it as a liquid-phase working fluid to the evaporator, wherein the evaporator has: a main body, which is a plate-shaped member, and a recess for providing the evaporation body is formed on the plate surface of the main body; and a lid body that covers the recess of the main body and the evaporation body provided in the recess, and the main body has a structural portion that makes the depth of the outside of the recess shallower than the depth of the central side of the recess, and the outside of the evaporation body provided in the recess is sandwiched between the structural portion and the lid body.

[0011] Advantages of the Invention

[0012] According to the technology disclosed in the present specification, a heat exchanger or the like that suppresses the size in the thickness direction can be manufactured. Brief Description of the Drawings

[0013] Figure 1 It is a schematic configuration diagram showing a loop heat pipe of the present embodiment.

[0014] Figure 2 It is an exploded perspective view of a loop heat pipe.

[0015] Figure 3 It is a detailed configuration diagram of the first side plate and the second side plate.

[0016] Figure 4 It is a diagram showing the configuration around the wick.

[0017] Figure 5 It is a diagram showing the configuration of the first support and the second support.

[0018] Figure 6 It is a schematic configuration diagram of the mask.

[0019] Figure 7 It is a diagram showing the process of forming the wick on the first side plate.

[0020] Figure 8 It is a diagram showing the process of forming the joining member on the second side plate.

[0021] Figure 9 It is a diagram showing the process of joining the wick and the joining member.

[0022] Figure 10 It is a diagram showing the configuration of the wick.

[0023] Figure 11 It is a diagram showing the configuration of the strut.

[0024] Figure 12 It is a diagram showing the process of forming the strut.

[0025] Figure 13 It is a diagram showing the configuration of the wing portion.

[0026] Figure 14 It is a diagram showing a device equipped with a loop heat pipe.

[0027] Figure 15 It is a diagram showing a modification example of the present embodiment. Detailed Embodiment

[0028] Hereinafter, with reference to the accompanying drawings, the present embodiment will be described in detail.

[0029] <Schematic Configuration of Loop Heat Pipe 1>

[0030] Figure 1 It is a schematic configuration diagram of the loop heat pipe 1 of the present embodiment.

[0031] First, refer to Figure 1, the configuration of the loop heat pipe 1 applicable to this embodiment will be described. The loop heat pipe 1 applicable to this embodiment is a heat exchanger configured to circulate a working fluid to cool a heating element 10 such as a central processing unit (CPU) of an electronic device or the like without supplying power from the outside.

[0032] Specifically, the loop heat pipe 1 includes: an evaporator 101 that evaporates the working fluid to utilize the latent heat during the vaporization of the working fluid to cool the heating element 10; and a condenser 107 that dissipates heat from the working fluid vaporized in the evaporator 101 to liquefy it.

[0033] In addition, the loop heat pipe 1 includes: a vapor line 105 that sends the working fluid vaporized in the evaporator 101 to the condenser 107; and a liquid line 109 that sends the working fluid liquefied in the condenser 107 to the evaporator 101. A working fluid that undergoes a phase change between the liquid phase and the gas phase is filled in the loop heat pipe 1. It should be noted that the working fluid can be, for example, water, alcohol (such as ethanol), ammonia, acetone, etc.

[0034] <Operation of the Loop Heat Pipe 1>

[0035] Next, with reference to Figure 1 , the operation inside the loop heat pipe 1 will be described.

[0036] The heat generated in the heating element 10 is transferred to the evaporator 101 (refer to arrow H1). The working fluid that has absorbed heat in the evaporator 101 vaporizes and is sent to the condenser 107 via the vapor line 105 (refer to arrow A1) (refer to arrow A2). The working fluid sent to the condenser 107 releases heat (refer to arrow H2) and liquefies. Then, the liquefied working fluid is sent back to the evaporator 101 via the liquid line 109 (refer to arrow A3) (refer to arrow A4). In this way, the loop heat pipe 1 functions as a non-electric fluid device. In addition, the loop heat pipe 1 is a two-phase heat transfer device driven by the capillary force of the fluid.

[0037] <Detailed Configuration of the Loop Heat Pipe 1>

[0038] Figure 2 is an exploded perspective view of the loop heat pipe 1.

[0039] Figure 3 is a detailed configuration diagram of the first side plate 111 and the second side plate 121.

[0040] Next, with reference to Figure 2 andFigure 3 The detailed configuration of the loop heat pipe 1 applicable to this embodiment will be described.

[0041] The general shape of the loop heat pipe 1 in this embodiment is flat. As Figure 2 shown, the loop heat pipe 1 has a configuration in which a wick 130 and a joint 150 are provided inside a housing 100 having a generally flat shape. Here, the housing 100 includes a first side plate 111 and a second side plate 121 each having a generally flat shape. In addition, the wick 130 and the joint 150 each have a generally flat shape. These wick 130 and joint 150 are sandwiched between the first side plate 111 and the second side plate 121.

[0042] Here, the first side plate 111 has a first inner surface 113 and a first outer surface 115 that are each generally rectangular in a front view. In addition, the first side plate 111 has a first through hole 1129 formed through the plate surface. The first through hole 1129 is a hole that is formed approximately at the center of the plate surface of the first side plate 111 and is generally rectangular in a top view.

[0043] In addition, the second side plate 121 has a second inner surface 123 and a second outer surface 125 that are each generally rectangular in a front view. In addition, the second side plate 121 has a second through hole 1229 formed through the plate surface. The second through hole 1229 is a hole that is formed approximately at the center of the plate surface of the second side plate 121 and is generally rectangular in a top view. When the first side plate 111 and the second side plate 121 are overlapped and arranged, the second through hole 1229 is provided at a position opposed to the first through hole 1129. To further explain, the first through hole 1129 and the second through hole 1229 are opposed to form a through hole 218.

[0044] The first side plate 111 and the second side plate 121 are formed of, for example, metal materials such as copper and copper alloys, stainless steel, titanium and titanium alloys, but are not limited to these. In addition, the wick 130 and the joint 150 are laminated and arranged between the first inner surface 113 of the first side plate 111 and the second inner surface 123 of the second side plate 121.

[0045] Here, in the loop heat pipe 1, heat diffusion can be achieved by using the first side plate 111 and the second side plate 121. In addition, the loop heat pipe 1 is generally formed in a flat plate shape with a thickness of, for example, 1 mm or less. In addition, the loop heat pipe 1 is formed, for example, in a size that can be provided in portable terminals such as smartphones and so-called plastic cards such as credit cards. Specifically, in the solution where the loop heat pipe 1 is provided in a portable terminal, it is formed in a so-called thin plate shape with an overall length of 100 mm, a width of 60 mm, and a thickness of 0.3 mm or less, for example. In addition, in the solution where the loop heat pipe 1 is provided in a plastic card, it is formed in a so-called thin plate shape with an overall length of 79 mm, a width of 52 mm, and a thickness of 0.3 mm or less, for example. Further, the loop heat pipe 1 is formed, for example, with a thickness of 5% or less of the size in the plane direction (for example, length or width), preferably 1% or less, and more preferably 0.3% or less.

[0046] It should be noted that in the following description, the thickness direction of the loop heat pipe 1, that is, Figure 2 the up-and-down direction in Figure 2 is sometimes simply referred to as the thickness direction. In addition, the lower side in the up-and-down direction in Figure 2 is sometimes referred to as the first surface side, Figure 2 and the upper side in the up-and-down direction in Figure 2 is sometimes referred to as the second surface side. In addition, the direction in which the wick 130 extends in the transfer direction (flow direction) of the working fluid in the evaporator 101, that is, the direction extending between the lower left and the upper right in Figure 2 is sometimes referred to as the transfer direction (flow direction). In addition, the lower left side in Figure 2 is sometimes referred to as the upstream side, and the upper right side is sometimes referred to as the downstream side. In addition, the direction intersecting the up-and-down direction and the phase direction, that is, the direction extending between the upper left and the lower right in Figure 2 is sometimes referred to as the width direction. In addition, the upper left side in Figure 2 is sometimes referred to as one side, and the lower right side is sometimes referred to as the other side.

[0047] Well, as shown in (A) of Figure 3 , a first recess 110 is formed on the first inner surface 113 of the first side plate 111. The first recess 110 is an annular region formed on the first inner surface 113 around the outer periphery of the first through hole 1129. Further, the first recess 110 has a first evaporator region 112, a first vapor pipe region 116, a first condenser region 117, a first liquid pipe region 118, and a first opening region 119 that are continuously arranged in a ring shape on the first inner surface 113 of the first side plate 111.

[0048] In addition, as Figure 3As shown in (B) thereof, a second recess 120 is formed in a second inner surface 123 of the second side plate 121. The second recess 120 is an annular region formed in the outer periphery of the second through hole 1229 in the second inner surface 123. In addition, the second recess 120 and the first recess 110 are in a mirror image shape. In other words, the first recess 110 and the second recess 120 are in a mirror-symmetrical relationship. To further explain, the second recess 120 has a second evaporator region 122, a second vapor pipe region 126, a second condenser region 127, a second liquid pipe region 128, and a second opening region 129 that are continuously arranged in a ring shape on the second inner surface 123 of the second side plate 121.

[0049] Here, when the first inner surface 113 of the first side plate 111 is attached to the second inner surface 123 of the second side plate 121, the first recess 110 and the second recess 120 are arranged opposite to each other. In this arrangement, the first evaporator region 112 and the second evaporator region 122 form the evaporator 101. Similarly, the first vapor pipe region 116 and the second vapor pipe region 126 form the vapor pipe 105. The first condenser region 117 and the second condenser region 127 form the condenser 107. The first liquid pipe region 118 and the second liquid pipe region 128 form the liquid pipe 109.

[0050] In addition, a plurality of first support portions 211 are formed on a first bottom surface 114 of the first recess 110. In the illustrated example, the first support portions 211 are respectively formed in the first evaporator region 112, the first vapor pipe region 116, the first condenser region 117, and the first liquid pipe region 118. In addition, a plurality of second support portions 221 are formed on a second bottom surface 124 of the second recess 120. In the illustrated example, the second support portions 221 are respectively formed in the second evaporator region 122, the second vapor pipe region 126, the second condenser region 127, and the second liquid pipe region 128.

[0051] Here, when the first inner surface 113 of the first side plate 111 is attached to the second inner surface 123 of the second side plate 121, the first support portion 211 and the second support portion 221 are arranged opposite to each other. To explain further, the top end of the first support portion 211 and the top end of the second support portion 221 are in a butting state. In this way, by the butting of the first support portion 211 and the second support portion 221, the contact between the first bottom surface 114 of the first recess 110 of the first side plate 111 and the second bottom surface 124 of the second recess 120 of the second side plate 121 is suppressed. That is, the first support portion 211 and the second support portion 221 are in a state of supporting the inside of the evaporator 101, the vapor pipe 105, the condenser 107, and the liquid pipe 109. In other words, the first support portion 211 and the second support portion 221 suppress the deformation of the evaporator 101, the vapor pipe 105, the condenser 107, and the liquid pipe 109. To explain further, the inside of the evaporator 101, the vapor pipe 105, the condenser 107, and the liquid pipe 109 becomes a negative pressure. Thus, the first support portion 211 and the second support portion 221 have the function of preventing the blockage and narrowing of the flow path of the working fluid formed inside the evaporator 101 and the like. In addition, in the illustrated example, the top end of the first support portion 211 is joined to the top end of the second support portion 221. Thereby, the separation (peeling) of the first inner surface 113 of the first side plate 111 from the second inner surface 123 of the second side plate 121 is suppressed. It should be noted that in the following description, the combination of the first support portion 211 and the second support portion 221 is sometimes collectively referred to as the support 210.

[0052] Then, after the first inner surface 113 of the first side plate 111 is joined to the second inner surface 123 of the second side plate 121, the first opening region 119 and the second opening region 129 in the illustrated example form an opening through which the working fluid can be injected into the first recess 110 and the second recess 120 from the outside. In addition, the opening formed by the first opening region 119 and the second opening region 129 is sealed after the working fluid is injected. To explain further, for the sake of convenience in explanation, the first opening region 119 and the second opening region 129 are formed in Figure 2 etc., but in the completed loop heat pipe 1, the first opening region 119 and the second opening region 129 are sealed (refer to Figure 1 ).

[0053] Next, the evaporator 101 formed by the first evaporator region 112 and the second evaporator region 122 will be described.

[0054] First, the first evaporator region 112 and the second evaporator region 122 are each substantially rectangular in a top view. Therefore, the interior of the evaporator 101 formed by the first evaporator region 112 and the second evaporator region 122 is a substantially rectangular parallelepiped-shaped space. In addition, a wick 130 is disposed inside the evaporator 101. By disposing this wick 130, the interior of the evaporator 101 is partitioned into a liquid pipe 109 side and a vapor pipe 105 side across the wick 130. Here, the space inside the evaporator 101 on the liquid pipe 109 side of the wick 130 functions as a liquid storage portion 160 for accommodating the working fluid in the liquid phase. In addition, the space inside the evaporator 101 on the vapor pipe 105 side of the wick 130 functions as a vapor space 140 through which the working fluid in the vapor phase passes.

[0055] <Configuration of Evaporator 101>

[0056] <Configuration around Wick 130>

[0057] Figure 4 It is a diagram showing the configuration around the wick 130.

[0058] Next, with reference to Figure 3 and Figure 4 the configuration of the wick 130 and the configuration around the wick 130 will be described.

[0059] First, the wick 130 is formed of a porous body such as porous metal, and such porous metal is formed of copper or the like. The wick 130 generates capillary force on the working fluid to move the working fluid. The effective pore diameter of the wick 130 is 0.1 μm to 50 μm. Preferably, the effective pore diameter of the wick 130 is 3.5 μm to 49 μm. More preferably, the effective pore diameter of the wick 130 is 5 μm to 45 μm. Further preferably, the effective pore diameter of the wick 130 is 20 μm to 40 μm. In addition, the porosity of the wick 130 is 20% to 90%. Preferably, the porosity of the wick 130 is 25% to 80%. It should be noted that the measurement methods for the effective pore diameter and the porosity are not particularly limited. For example, it can be measured by the following methods: apparent density measurement based on the water immersion method, pore diameter distribution measurement based on the mercury intrusion method, or pore observation based on X-ray CT (Computed Tomography).

[0060] As Figure 4As shown, the general shape of the wick 130 is a rake shape (fork shape). Specifically, the wick 130 has: a wick base 131 having a substantially rectangular shape, with the long dimension direction along the width direction; wick claws 133 protruding from the wick base 131 toward the downstream side in the transfer direction; and a wick convex portion 137, which is a portion protruding from the wick base 131 toward the upstream side in the transfer direction. In the illustrated example, a plurality of wick claws 133 are provided at a predetermined interval in the width direction. In other words, the wick 130 has a plurality of slits 135 formed along the transfer direction on the downstream side in the transfer direction. It should be noted that the end portion on the upstream side in the transfer direction of the slit 135 is sometimes referred to as the slit bottom 136. Further, in the illustrated example, the wick convex portion 137 is formed at the central portion in the width direction of the wick base 131.

[0061] Here, the general shapes of the wick base 131 and the wick claws 133 in the illustrated wick 130 are comb-tooth shapes. In the wick 130 formed in this comb-tooth shape, the slit 135 functions as a vapor groove, that is, a so-called groove, which promotes the flow of the working fluid vaporized in the wick 130 toward the vapor pipe 105. To further explain, in the illustrated example, by alternately arranging the wick claws 133 and the slits 135 in the same plane, compared with a configuration in which the wick claws 133 and the slits 135 are arranged side by side in the thickness direction, the mechanical strength can be maintained while thinning the wick 130, the first side plate 111, and the second side plate 121. Further, preferably, by providing the wick claws 133 and the slits 135 in the same plane, the wick claws 133 are in contact with both the first side plate 111 and the second side plate 121. Thus, the degree of freedom in the arrangement of the heating element 10 ( Figure 1 ) as a heat source is increased. That is, since the wick claws 133 can be heated from both the first side plate 111 and the second side plate 121, the heating element 10 can be provided on either one or both of the first outer surface 115 of the first side plate 111 and the second outer surface 125 of the second side plate 121.

[0062] In addition, the tips of the illustrated wick claws 133 and the slit bottoms 136 are rounded (curved) shapes. Details will be described later. The wick 130 is formed by coating a metal paste. By setting the tips of the wick claws 133 and the slit bottoms 136 to a curved shape, it is easier to coat the metal paste compared to a non-curved shape such as an angular shape.

[0063] Then, in a case where there is less working fluid stored in the liquid storage unit 160 or the like, the working fluid may be unevenly distributed in the liquid storage unit 160. And due to this unevenness of the working fluid, it may be difficult to supply the working fluid to the wick 130, and the operating performance of the wick 130 may be reduced. Therefore, a wick convex portion 137 is formed on the illustrated wick 130. By forming the wick convex portion 137 that protrudes into the liquid storage unit 160, even when the working fluid is unevenly distributed in the liquid storage unit 160, the working fluid can be stably supplied to the wick base portion 131 and the wick claw portion 133 via the wick convex portion 137.

[0064] It should be noted that the wick convex portion 137 can be regarded as another wick, i.e., an auxiliary wick, for supplying the working fluid to the wick base portion 131 and the like. In addition, the wick convex portion 137 may have a configuration in which a prescribed capillary force acts, and its material, shape (for example, columnar structure, mesh structure), etc. are not particularly limited. It should be noted that it is preferable that the size of the wick convex portion 137 is set so that the flow pressure loss is not greater than a prescribed value.

[0065] In addition, the wick 130 is configured to have a thickness of 0.01 mm to 1 mm, and more preferably a thickness of 0.1 mm to 0.2 mm. Here, the length of the wick base portion 131 of the wick 130 in the width direction is, for example, 10 mm to 300 mm, and the length in the transfer direction is 1 mm to 100 mm. The ratio of the thickness of the wick base portion 131 to the length in the transfer direction is configured to be, for example, 0.01% to 100%, and more preferably 0.1% to 10%. It should be noted that the thickness of the wick 130 in the illustrated example is 0.2 mm. In addition, the length in the width direction is 21 mm, and the length in the transfer direction is 2 mm.

[0066] The length of the wick claw portion 133 in the width direction is 0.5 mm to 2.0 mm, and the length in the transfer direction is 10 mm to 20 mm. In addition, the length of the slit 135 in the width direction is, for example, 0.5 mm to 2.0 mm. To further illustrate, the length of the slit 135 in the width direction is substantially the same as the length of the wick claw portion 133. In addition, in the illustrated example, the heating element 10 (refer to Figure 1 ) is, for example, 10 mm in width and 10 mm in length. Therefore, the area where the wick base portion 131 and the plurality of wick claw portions 133 in the wick 130 are provided has dimensions of width and length that are larger than those of the heating element 10.

[0067] In addition, the length of the wick convex portion 137 in the width direction is 1 mm to 30 mm, and the length in the transfer direction is 10 mm to 100 mm. The wick convex portion 137 in the illustrated example is larger than the wick claw portion 133 in the width direction. In addition, the wick convex portion 137 is larger than the wick claw portion 133 in the transfer direction.

[0068] Then, as described above, the wick 130 is disposed inside the housing 100. The wick 130 is disposed between the first side plate 111 and the second side plate 121 in the thickness direction. Further, the wick 130 divides the vapor space 140 and the liquid storage portion 160 inside the housing 100, that is, between the first side plate 111 and the second side plate 121. Here, it is assumed that a gap (clearance) is formed between the inner peripheral surface of the housing 100 and the wick 130. To further explain, if a gap is formed between the first side plate 111 and the wick 130 or between the second side plate 121 and the wick 130, the liquid-phase working fluid may flow in (leak) into the vapor space 140, and the gas-phase working fluid may flow in (flow backward) into the liquid storage portion 160. And these inflows will reduce the heat exchange rate of the loop heat pipe 1.

[0069] Therefore, in the present embodiment, the material constituting the wick 130 is coated on the first inner surface 113 of the first side plate 111, thereby forming the wick 130 on the first side plate 111 (details will be described later). Thereby, the formation of a gap between the wick 130 and the first inner surface 113 of the first side plate 111 is suppressed.

[0070] Further, in the present embodiment, the joining member 150 is disposed overlapping the wick 130. Thereby, the formation of a gap between the wick 130 and the second inner surface 123 of the second side plate 121 is suppressed.

[0071] Further, in the present embodiment, the first support 1123 and the second support 1124 are formed on the first bottom surface 114 of the first recess 110 provided in the first side plate 111. Further, the third support 1223 and the fourth support 1224 are formed on the second bottom surface 124 of the second recess 120 provided in the second side plate 121 (refer to (B) of Figure 3 . By these first support 1123, second support 1124, third support 1223, and fourth support 1224, the formation of a gap at both ends in the width direction of the wick 130 is suppressed.

[0072] Then, as Figure 4 shown, the joining member 150 is a plate-like member having a substantially rectangular shape with its long dimension direction along the width direction. In the illustrated example, the length of the joining member 150 in the transfer direction is 2 mm, and the length in the width direction is 19 mm. The joining member 150 is formed of a metal such as copper or bronze.

[0073] Here, the joining member 150 is provided at a position covering the wick base portion 131 of the wick 130. More specifically, the upstream end face 155 of the joining member 150 of the joining member is aligned with the upstream end face 132 of the wick base portion 131 in the transfer direction. In addition, the position of the downstream end face 157 of the joining member 150 of the joining member is downstream of the upstream end face 132 and upstream of the imaginary line L11 along the bottom of the slit 136 in the transfer direction. Here, when the downstream end face 157 of the joining member is upstream of the upstream end face 132 in the transfer direction, leakage of the working fluid may occur. In addition, when the downstream end face 157 of the joining member is downstream of the imaginary line L11 in the transfer direction, the function of the slit 135 may be reduced.

[0074] <First support body 1123 and second support body 1124>

[0075] Figure 5 It is a diagram showing the configuration of the first support body 1123 and the second support body 1124.

[0076] Next, with reference to Figure 5 , the configuration of the first support body 1123 and the second support body 1124 will be described. More specifically, Figure 5 (A) of Figure 5 is a plan view of the periphery of the first support body 1123 and the second support body 1124, Figure 5 (B) of Figure 5 is a cross-sectional view taken along VB-VB of (A) of

[0077] As Figure 5 (A) shows, the first support body 1123 and the second support body 1124 are each in a substantially rectangular parallelepiped shape and are formed on the first bottom surface 114 of the first recess 110. The first support body 1123 and the second support body 1124 are formed such that their long dimension directions are along the transfer direction. In addition, the first support body 1123 and the second support body 1124 are formed to be separated from each other in the width direction. The regions where the first support body 1123 and the second support body 1124 are formed are positions facing the ends in the width direction of the wick 130.

[0078] The first support body 1123 is a portion protruding from the inner side surface, i.e., the first opposing surface 1131, of the first recess 110 in the width direction, and has a first support upper surface 1133 facing the upper side in the thickness direction and a first support side surface 1135 facing one side in the width direction.

[0079] The second support 1124 is a part that protrudes in the width direction from the inner side surface of the first recess 110, that is, the second opposing surface 1132, and has a second support upper surface 1134 facing the upper side in the thickness direction and a second support side surface 1136 facing the other side in the width direction.

[0080] Here, the first support upper surface 1133 and the second support upper surface 1134 are substantially rectangular planes. Moreover, substantially rectangular parallelepiped-shaped spaces are formed above the respective upper sides of the first support upper surface 1133 and the second support upper surface 1134. These spaces can be regarded as notches 1128 formed on the first side plate 111 (refer to Figure 5 (B) of ). Details will be described later. The end portion in the width direction of the liquid absorption core 130 is disposed in the notch 1128.

[0081] <First conical surface 1125 and second conical surface 1126>

[0082] Next, with reference to Figure 5 , the configurations of the first conical surface 1125 and the second conical surface 1126 will be described.

[0083] Although not described above, as shown in Figure 5 , a first conical surface 1125 is formed at a position adjacent to the first support 1123 on the upstream side in the transfer direction of the first support 1123 in the first recess 110. In addition, a second conical surface 1126 is formed at a position adjacent to the second support 1124 on the upstream side in the transfer direction of the second support 1124 in the first recess 110. In addition, a third conical surface 1225 and a fourth conical surface 1226 are formed on the upstream sides in the transfer directions of the third support 1223 and the fourth support 1224 in the second recess 120, respectively (refer to Figure 3 (B) of ). The third conical surface 1225 and the fourth conical surface 1226 are mirror images of the first conical surface 1125 and the second conical surface 1126. These first conical surface 1125, second conical surface 1126, third conical surface 1225, and fourth conical surface 1226 are configured to guide the working fluid.

[0084] Hereinafter, the first conical surface 1125 and the second conical surface 1126 will be further described as examples. First, as shown in Figure 5As shown in (A) thereof, the first conical surface 1125 inclines in the direction of protruding from the first side surface 1121 as it advances toward the downstream side in the transfer direction. In addition, the second conical surface 1126 inclines in the direction of protruding from the second side surface 1122 as it advances toward the downstream side in the transfer direction. The first conical surface 1125 and the second conical surface 1126 guide the flow of the working fluid. To further explain, through the first conical surface 1125 and the second conical surface 1126, the flow path of the working fluid narrows in the width direction as it advances toward the downstream side in the transfer direction. And, the working fluid advancing toward the downstream side in the first recess 110 is guided toward the center side in the width direction of the flow path by the first conical surface 1125 and the second conical surface 1126 (refer to Figure 5 the arrow C9 in (A) thereof).

[0085] <Operation of the evaporator 101>

[0086] Next, with reference to Figure 5 (A) thereof, the operation inside the evaporator 101 will be described.

[0087] First, the liquid-phase working fluid accommodated in the liquid storage portion 160 flows toward the wick base portion 131 (refer to the arrow C1) and penetrates into the wick base portion 131. In addition, a part of the liquid-phase working fluid accommodated in the liquid storage portion 160 penetrates into the wick convex portion 137 (refer to the arrow C3), and while moving inside the wick convex portion 137 by capillary force, it tends toward the wick base portion 131 (refer to the arrow C5). Moreover, a part of the liquid-phase working fluid accommodated in the liquid storage portion 160 tends toward the wick base portion 131 while being guided by the first conical surface 1125, the second conical surface 1126, the third conical surface 1225, and the fourth conical surface 1226 (refer to the arrow C9).

[0088] And, the liquid-phase working fluid moves inside the wick base portion 131 by the capillary force of the wick base portion 131 and is heated by the heat of the heating element 10 to be vaporized. The vaporized working fluid moves toward the steam pipe 105 side through the slit 135 or the like (refer to the arrow C7), then flows out from the steam pipe 105 and is sent to the condenser 107 (refer to Figure 1 ). And, the working fluid liquefied in the condenser 107 (refer to Figure 1 ) flows into the evaporator 101 and penetrates into the wick 130 again through the liquid storage portion 160. Thus, in the wick 130, the flow of the working fluid does not interrupt, and the above cycle is repeated. And, the heat generated by the heating element 10 is transferred from the evaporator 101 to the condenser 107 (refer to Figure 1 ).

[0089] <Forming process of the first side plate 111 and the second side plate 121>

[0090] Next, with reference to Figure 5 , a schematic overview of the forming process of the first side plate 111 and the second side plate 121 will be described.

[0091] First, as described above, in the first side plate 111 and the second side plate 121, a flat member made of a metal material such as copper is processed to form the first recess 110 and the second recess 120. In the illustrated example, an etching process is performed on a copper flat plate with a thickness of 0.15 mm (refer to the thickness T1 of (B) in Figure 5 ) to form the first recess 110 and the second recess 120. Here, the depth of the first recess 110 and the second recess 120 is 0.1 mm (refer to the depth G1 of (B) in Figure 5 ). That is, the thickness of the bottom of the region where the first recess 110 and the second recess 120 are formed in the first side plate 111 and the second side plate 121 is 0.05 mm (refer to the thickness T3 of (B) in Figure 5 ). To further explain, by etching, more than 50% of the thickness of the first side plate 111 and the second side plate 121 is recessed.

[0092] Here, details will be described later. By performing an etching process different from the etching process for forming the first recess 110 and the second recess 120, the first support 1123, the second support 1124, the third support 1223, and the fourth support 1224 are formed. Here, the depth to the first support upper surface 1133 of the first support 1123 is 0.05 mm (refer to the depth G3 of (B) in Figure 5 ). That is, the thickness of the bottom of the region where the first support 1123, the second support 1124, the third support 1223, and the fourth support 1224 are formed in the first side plate 111 and the second side plate 121 is 0.1 mm (refer to the thickness T5 of (B) in Figure 5 ). Thus, compared with other regions in the first recess 110 and the second recess 120, the region where the first support 1123, the second support 1124, the third support 1223, and the fourth support 1224 are formed has a thicker bottom thickness. In addition, the first support 1123, the second support 1124, the third support 1223, and the fourth support 1224 can be regarded as a structure that raises the bottom of the first recess 110 and the second recess 120.

[0093] In addition, in the above etching process, by masking the regions where the first support 1123 and the second support 1124 are formed, the first support 1123 and the second support 1124 are formed in the first recess 110 and the second recess 120. In addition, in order to be able to take out the first side plate 111 and the second side plate 121, through etching, i.e., outer contour copper plate etching, is performed around the outer shapes of the first side plate 111 and the second side plate 121. In addition, in the illustrated example, through the through etching, a first through hole 1129 is formed in the first side plate 111, and a second through hole 1229 is formed in the second side plate 121.

[0094] <Process of forming the liquid absorption core 130 and the joining member 150>

[0095] Next, with reference to Figure 4 and Figure 5 , an outline of the process of forming the liquid absorption core 130 and the joining member 150 will be described.

[0096] First, in the present embodiment, instead of disposing the pre-formed liquid absorption core 130 and the joining member 150 on the first side plate 111 and the second side plate 121, the liquid absorption core 130 and the joining member 150 are formed on the first side plate 111 and the second side plate 121. Then, the first side plate 111 on which the liquid absorption core 130 is formed and the second side plate 121 on which the joining member 150 is formed are overlapped and bonded, so that the liquid absorption core 130 and the joining member 150 are fixed to each other.

[0097] Here, the illustrated liquid absorption core 130 is formed on the first side plate 111 by coating the material of the liquid absorption core 130 on the first side plate 111. More specifically, the liquid absorption core 130 is formed by coating a metal paste containing pure copper powder in a predetermined region of the first side plate 111. It should be noted that when coating the liquid absorption core 130, a mask 180 (refer to Figure 6 described later) will be used.

[0098] In addition, the illustrated joining member 150 is formed on the second side plate 121 by coating the material of the joining member 150 on the second side plate 121. More specifically, the joining member 150 is formed by coating a metal paste containing copper and bronze powder in a predetermined region of the second side plate 121. Here, by masking the periphery of the region where the joining member 150 is formed by a so-called masking tape, i.e., the fifth masking member M23 (refer to Figure 8 (F) described later) and coating the metal paste, the joining member 150 is formed.

[0099] <Mask 180>

[0100] Figure 6 is a schematic configuration diagram of the mask 180.

[0101] The mask 180 is, for example, a metal member of a flat plate portion with a plate thickness of 0.15 mm. A liquid absorption core type opening 190 serving as a through hole is formed in the mask 180. The liquid absorption core type opening 190 has: a liquid absorption core base region 191 which is a region where the liquid absorption core base 131 is formed; a liquid absorption core claw region 193 which is a region where the liquid absorption core claw 133 is formed; and a liquid absorption core convex region 197 which forms the liquid absorption core convex 137. Here, the liquid absorption core base region 191 is a substantially rectangular portion whose long dimension direction is along the width direction. The liquid absorption core claw region 193 is a portion protruding from the liquid absorption core base region 191 toward the downstream side in the transfer direction. In addition, the liquid absorption core convex region 197 is a portion protruding from the liquid absorption core base region 191 toward the upstream side in the transfer direction.

[0102] The mask 180 is disposed in alignment with the first side plate 111 in which the first recess 110 is formed. Then, a metal paste containing pure copper powder is guided onto the mask 180 to the liquid absorption core type opening 190, and excess metal paste and the like are scraped off using a rubber squeegee (so-called scraper) or the like for coating. Thus, the material of the liquid absorption core 130 is disposed in the first recess 110 with a predetermined thickness (for example, 0.25 mm). The coated material of the liquid absorption core 130 is solidified by sintering or the like, and thus, the liquid absorption core 130 is formed in the first recess 110. It should be noted that by using the mask 180, the process of forming the liquid absorption core 130 can be simplified.

[0103] <Manufacturing Process of Loop Heat Pipe 1>

[0104] Figure 7 It is a diagram showing the process of forming the liquid absorption core 130 on the first side plate 111.

[0105] Figure 8 It is a diagram showing the process of forming the joining member 150 on the second side plate 121.

[0106] Figure 9 It is a diagram showing the process of joining the liquid absorption core 130 and the joining member 150.

[0107] It should be noted that especially in Figures 7 to 9 the vertical dimensions of each component are described in an emphasized (magnified) manner.

[0108] Next, with reference to Figures 7 to 9 , an example of the manufacturing process of the loop heat pipe 1 in the present embodiment will be described. The manufacturing process of the loop heat pipe 1 in the present embodiment includes: a forming process of forming a housing 100 composed of a first side plate 111 and a second side plate 121; and a filling process of filling a working fluid into the housing 100.

[0109] In addition, the forming process further includes three processes. These three processes are: forming the liquid absorption core 130 on the first side plate 111; forming the engaging member 150 on the second side plate 121; and joining the liquid absorption core 130 formed on the first side plate 111 and the engaging member 150 formed on the second side plate 121. Hereinafter, these three processes will be described.

[0110] <Liquid Absorption Core 130 Forming Process>

[0111] First, with reference to Figure 7 , the process of forming the liquid absorption core 130 on the first side plate 111 will be described. In the following processes, a first recess 110, a first support 1123, and a second support 1124 are formed on the first side plate 111, and then the liquid absorption core 130 is formed in the first recess 110.

[0112] First, the process of forming the first recess 110, the first support 1123, and the second support 1124 on the first side plate 111 will be described. Specifically, as shown in (A) of Figure 7 , the first side plate 111 is placed on the support table TB. It should be noted that although not shown in the figure, the following processes are performed in the state of being placed on the support table TB.

[0113] Next, as shown in (B) of Figure 7 , the first masking member M11 is used to cover the area of the first inner surface 113 except for the areas where the first support 1123 and the second support 1124 are to be formed. And, as shown in (C) of Figure 7 , after etching the first side plate 111, the first masking member M11 is removed. The areas where etching is performed in this process form the first support upper surface 1133 and the second support upper surface 1134.

[0114] Next, as shown in (D) of Figure 7 , the second masking member M12 is used to cover the area of the first inner surface 113 except for the area of the first bottom surface 114 of the first recess 110 to be formed. And, as shown in (E) of Figure 7 , after etching the first side plate 111, the second masking member M12 is removed. The areas where etching is performed in this process form the first bottom surface 114. In addition, through this process, the state where the first recess 110, the first support 1123, and the second support 1124 are formed on the first side plate 111 is achieved.

[0115] Next, the liquid absorption core 130 is formed in the first recess 110, the first support 1123, and the second support 1124. Specifically, as shown in (F) of Figure 7 , the mask 180 is disposed on the first inner surface 113. And, as shown in Figure 7As shown in (G), the first metal paste 149 that constitutes the liquid absorption core 130 is applied. At this time, a part of the first metal paste 149 is also placed on the first support 1123 and the second support 1124.

[0116] Next, as Figure 7 shown in (H), the first metal paste 149 is sintered in a sintering furnace (not shown) under specified conditions (details will be described later) to form the liquid absorption core 130. This liquid absorption core 130 is fixed to the first bottom surface 114, the first support 1123, and the second support 1124.

[0117] <Forming process of the joining member 150>

[0118] Next, with reference to Figure 8 , the process of forming the joining member 150 on the second side plate 121 will be described. In the following process, a second recess 120, a third support 1223, and a fourth support 1224 are formed on the second side plate 121, and then the joining member 150 is formed in the second recess 120.

[0119] First, the process of forming the second recess 120, the third support 1223, and the fourth support 1224 on the second side plate 121 will be described. Specifically, as Figure 8 shown in (A), the second side plate 121 is placed on the support table TB. It should be noted that although not shown, the following processes are performed in the state of being placed on the support table TB.

[0120] Next, as Figure 8 shown in (B), the third masking member M21 is used to cover the region of the second inner surface 123 except for the regions where the third support 1223 and the fourth support 1224 are to be formed. And, as Figure 8 shown in (C), after etching the second side plate 121, the third masking member M21 is removed. The regions where etching is performed in this process form the third support upper surface 1233 and the fourth support upper surface 1234.

[0121] Next, as Figure 8 shown in (D), the fourth masking member M22 is used to cover the region of the second inner surface 123 except for the region of the second bottom surface 124 where the second recess 120 is to be formed. And, as Figure 8 shown in (E), after etching the second side plate 121, the fourth masking member M22 is removed. The regions where etching is performed in this process form the second bottom surface 124. In addition, in this process, the state where the second recess 120, the third support 1223, and the fourth support 1224 are formed on the second side plate 121 is achieved.

[0122] Next, a joining member 150 is formed in the second recess 120. Specifically, as shown in (F) of Figure 8 , a fifth masking member M23 is disposed on the first inner surface 113. And, as shown in (G) of Figure 8 , a second metal paste 159 that constitutes the joining member 150 is applied.

[0123] Next, as shown in (H) of Figure 8 , the second metal paste 159 is heated in a sintering furnace (not shown) under specified conditions (details will be described later) to be sintered, thereby forming the joining member 150. This joining member 150 is in a state of being fixed to the second bottom surface 124, the third support 1223, and the fourth support 1224.

[0124] <Joining process of the liquid absorption core 130 and the joining member 150>

[0125] Next, with reference to Figure 9 , the process of joining the liquid absorption core 130 and the joining member 150 will be described.

[0126] First, as shown in (A) of Figure 9 , the first side plate 111 and the second side plate 121 are overlapped. Thereby, the liquid absorption core 130 and the joining member 150 are opposed to each other and are arranged to abut against each other. And, as shown in (B) of Figure 9 , the first side plate 111 and the second side plate 121 are pressed (refer to F11 in the figure), and after reducing the thickness of the liquid absorption core 130, the first side plate 111 and the second side plate 121 are heated in a sintering furnace (not shown). Thereby, the liquid absorption core 130 and the joining member 150 are joined.

[0127] Next, as shown in (C) of Figure 9 , after taking out of the furnace, a process for improving airtightness is performed. Specifically, a laser LA is irradiated to the first side plate 111 and the second side plate 121. Thereby, the first side plate 111 and the second side plate 121 are joined to each other, and the airtightness is further improved. In the illustrated example, in the region where the first support 1123 and the third support 1223 are opposed to each other, a gap GA is formed between the liquid absorption core 130. Similarly, a gap GA is formed in the region where the second support 1124 and the fourth support 1224 are opposed to each other.

[0128] Next, as shown in (D) of Figure 9 , a part (specific region) of the first side plate 111 and the second side plate 121 is pressed. Specifically, the regions where the first support 1123 and the third support 1223 are opposed to each other and where the second support 1124 and the fourth support 1224 are opposed to each other in the first side plate 111 and the second side plate 121 are pressed (F13 in the figure) by a stamping machine (not shown). Thereby, as shown in Figure 9As shown in (E), the area where the first support 1123 and the third support 1223 face each other is pressed flat, and the gap GA decreases (in the illustrated example, it becomes a state without the gap GA). Thus, the area where the first support 1123 and the third support 1223 face each other becomes a state filled with the liquid absorption core 130. Similarly, in the area where the second support 1124 and the fourth support 1224 face each other, the gap GA also decreases and becomes a state filled with the liquid absorption core 130. It should be noted that in the above description, it is omitted that in a specific area that has been pressurized, the first groove 1127 and the second groove 1128, which are recesses (pressing marks), are formed. Through the first groove 1127 and the second groove 1128, the heat transfer to the liquid absorption core 130 is promoted. To further explain, for example, during the heating in the bonding process of the liquid absorption core 130 and the bonding member 150, sometimes the components of the bonding member 150 diffuse into the second side plate 121, resulting in a reduction in the strength of the housing 100. However, by pressurizing specific areas of the first side plate 111 and the second side plate 121 to form the first groove 1127 and the second groove 1128, the reduction in the strength of the housing 100 can be suppressed.

[0129] It should be noted that in the illustrated example, as Figure 7 shown in (H) and Figure 8 shown in (H), when sintering the first metal paste 149 and the second metal paste 159, the first side plate 111 and the second side plate 121 are heated while being supported by a support table TB that is a flat surface. Thus, compared with the case where the first side plate 111 and the second side plate 121 are not supported by the support table TB, the deformation of the first side plate 111 and the second side plate 121 during heating can be suppressed.

[0130] Well, in the illustrated example, as described above Figure 7 shown in (H), the first side plate 111 is heated to form the liquid absorption core 130. In addition, as Figure 8 shown in (H), the second side plate 121 is heated to form the bonding member 150. Here, since at least one of the first side plate 111 and the second side plate 121 is heat-treated, the reflectivity of the laser LA of each of the first side plate 111 and the second side plate 121 decreases (the absorption rate increases). Due to this change in reflectivity, the bonding of the first side plate 111 and the second side plate 121 by the laser LA becomes more reliable. It should be noted that the heat treatment process shown in Figure 7 (H) above or Figure 8 (H) can be regarded as a process for performing pretreatment for laser welding. In other words, the heat treatment process shown in Figure 7 (H) above or Figure 8 (H) can be regarded as the following process: performing a pretreatment process of the copper plate simultaneously with the sintering process of the liquid absorption core 130 or the bonding member 150.

[0131] In addition, as described above, as Figure 9 shown in (D) above, by pressing both ends in the width direction of the wick 130, the contact between the wick 130 and the first recess 110 (second recess 120) becomes more reliable. That is, the formation of gaps at both ends in the width direction of the wick 130 is suppressed. Here, as Figure 7 shown in (G) above, the first metal paste 149 that constitutes the wick 130 by sintering as described above is applied to the first side plate 111 via the mask 180. In this application, both ends in the width direction of the first metal paste 149 may sometimes separate from the first recess 110 due to phenomena such as so-called slumping.

[0132] In the present embodiment, in order to suppress the gaps at both ends in the width direction of the first metal paste 149, the first support 1123 and the second support 1124 are formed. That is, a part of the first metal paste 149 is placed on the first support 1123 and the second support 1124 that are bottom elevation portions. Thereby, for example, even when the coating by the above-mentioned rubber squeegee is insufficient, the first metal paste 149 can reach both ends in the width direction.

[0133] In addition, in the present embodiment, as Figure 7 shown in (H) above, after sintering the first metal paste 149 and bonding it to the bonding member 150, as Figure 9 shown in (D) above, the regions of the first support 1123 and the second support 1124 are pressurized. By this pressurization, the gaps at both ends in the width direction of the wick 130 are suppressed. Here, in the illustrated example, the region having a thickness greater than the region where the first support 1123 and the second support 1124 are formed, that is, the region where the first bottom surface 114 is formed, is pressurized. In this way, by pressurizing the thick region, the occurrence of breakage and the like due to pressurizing the thin region is suppressed. In addition, in the illustrated example, the copper plate forming the portions at both ends in the width direction of the wick 130 is made into a stepped shape to increase the thickness of the bottom, thereby forming a structure capable of extrusion processing. In addition, the first support 1123 and the second support 1124 can be regarded as reinforcing portions.

[0134] <First Metal Paste 149 and Second Metal Paste 159>

[0135] The first metal paste 149 and the second metal paste 159 are formed in the following manner, for example. The first metal paste 149 that constitutes the wick 130 can be formed by mixing pure copper powder with a particle size of 45 μm or less with a binder solution. In addition, the second metal paste 159 that constitutes the joint 150 can be formed by mixing bronze powder with a particle size of 45 μm or less with a binder solution. However, the particle size and material of the metal powder used in the first metal paste 149 that constitutes the wick 130 and the second metal paste 159 that constitutes the joint 150 are just examples and are not limited thereto. The binder solution is composed of a binder component and an organic solvent. The binder component can be selected from acrylic, butyral, cellulose, etc., and the organic solvent can be selected from acetone, benzene, isopropyl alcohol, methanol, ethanol, toluene, n-butanol, xylene, ethylene glycol, ethyl acetate, terpineol, butyl acetate, tetrahydrofuran (THF), carbon tetrachloride, methyl ethyl ketone (MEK), chloroform, methyl isobutyl ketone (MIBK), n-hexane, methanol, cyclohexane, etc., but is not limited thereto.

[0136] The first metal paste 149 and the second metal paste 159 are subjected to debinding and sintering in a belt-type sintering furnace. Here, the first metal paste 149 and the second metal paste 159 disposed (coated) on the first side plate 111 and the second side plate 121 are sintered under the following conditions, for example. The debinding temperature of the first metal paste 149 is 400°C to 600°C, the sintering is 700°C to 1050°C, the holding time is 10 minutes to 40 minutes, and the atmosphere gas is 10% to 95% nitrogen and 5% to 90% hydrogen. In addition, the debinding temperature of the second metal paste 159 is 400°C to 600°C, the sintering is 500°C to 700°C, the holding time is 10 minutes to 60 minutes, and the atmosphere gas is 10% to 95% nitrogen and 5% to 90% hydrogen. In addition, the atmosphere for degreasing and sintering is not limited to a nitrogen-hydrogen mixture, and can also be pure hydrogen, argon, an argon-hydrogen mixture, or vacuum, etc. However, the debinding and sintering conditions are an example in the case where pure copper powder with a particle size of 45 μm or less is used in the first metal paste 149 that constitutes the wick 130 and bronze powder with a particle size of 45 μm or less is used in the second metal paste 159 that constitutes the joint 150, and can be appropriately selected according to the metal powder material and binder component used.

[0137] <Fixing of the first side plate 111 and the second side plate 121>

[0138] As Figure 9 shown in (B) of, the fixing of the first side plate 111 and the second side plate 121 is carried out under the following conditions, for example. First, in a state where the first side plate 111 and the second side plate 121 overlap, the portion where the wick 130 and the joint 150 are formed is pressed from the outside (refer to the arrow F11 in the figure), and the thickness after the wick 130 and the joint 150 are adhered is adjusted to be equal to the flow path height.

[0139] Next, the wick 130 and the joint 150 are joined in a mesh belt sintering furnace. This joining is performed, for example, under the following heat treatment conditions. That is, the temperature is 500°C to 700°C, the holding time is 10 minutes to 40 minutes, and the atmosphere gas is 10% to 95% nitrogen and 5% to 90% hydrogen. The atmosphere is not limited to a nitrogen-hydrogen mixture, and it can also be pure hydrogen, argon, an argon-hydrogen mixture, or vacuum, etc. In addition, the first side plate 111 and the second side plate 121 are clamped by a ceramic plate, and a heavy object is placed to make the load 1 kg and heat treatment is performed.

[0140] Then, in a state where the wick 130 and the joint 150 are already joined, the outer surface of the first side plate 111 or the second side plate 121, particularly the outer peripheral edge and the inner peripheral edge, and, if necessary, the support column 210 are laser welded, thereby joining the first side plate 111 and the second side plate 121. At this time, in order to improve the weldability, a jig (not shown) in which the first side plate 111 and the second side plate 121 are in close contact is used for laser welding.

[0141] It should be noted that in the above example, the following situation has been described: after joining the wick 130 and the joint 150 in a mesh belt sintering furnace, the first side plate 111 and the second side plate 121 are laser welded. However, it is also possible to laser weld the first side plate 111 and the second side plate 121 and then join the wick 130 and the joint 150 in a mesh belt sintering furnace.

[0142] It should be noted that a leakage test was performed on the loop heat pipe 1 formed under the above conditions, and it was confirmed that there was no degassing problem. In addition, a heat load test was performed on the manufactured loop heat pipe 1, and it was confirmed that it operated at 4.5 W to 10 W.

[0143] <Joining via the joint 150>

[0144] As described above, the wick 130 and the second side plate 121 are fixed to each other via the joint 150. The fixing performed by this joint 150 will be described.

[0145] First, as Figure 7As shown in (H), the first surface side in the thickness direction (the lower side in the figure) of the wick 130 formed by sintering the first metal paste 149 is in a state of being joined to the first side plate 111. In addition, it is required that the second surface side in the thickness direction (the upper side in the figure) of the wick 130 be joined (sealed) to the second side plate 121. Here, different from this embodiment, when soldering (for example, 500 °C) is used instead of the joining member 150 to join the wick 130 to the second side plate 121, the solder will be absorbed by the wick 130, which may reduce the function of the wick 130. In addition, different from this embodiment, when brazing (for example, 800 °C) or diffusion bonding (for example, 1000 °C) is used to join the wick 130 to the second side plate 121, due to deformation such as flexure of the first side plate 111 and the second side plate 121, the flow path of the working fluid may be blocked.

[0146] Therefore, in the illustrated example, the joining member 150 is used for joining. As the material of the joining member 150, a material same as the material of the wick 130 (for example, pure copper) or a material having a lower melting point than it (for example, bronze) can be used. The material of the joining member 150 is not particularly limited as long as it is easy to alloy with the wick 130 and the second side plate 121 or is easy to fuse. For example, when the wick 130 is formed of pure copper, other materials such as brass can be used as the joining member 150. It should be noted that the material of the joining member 150 can be regarded as a material having the same composition (for example, copper) as the wick 130 and the second side plate 121. In addition, the material of the joining member 150 can be regarded as a material having the same melting point as or lower than the alloy of the second side plate 121. It should be noted that in the above example, the sintering of the first metal paste 149, that is, the first heating temperature is 700 °C to 1050 °C. In addition, the joining of the wick 130 and the joining member 150, that is, the second heating temperature is 500 °C to 700 °C, which is lower than the first temperature. Thereby, the compositional change of the wick 130 accompanying the second heating is reduced.

[0147] In this way, by joining the wick 130 and the joining member 150, the wick 130 is fixed relative to the first side plate 111 and the second side plate 121. The fixed wick 130 and the joining member 150 function as a pressure partition between the vapor space 140 and the liquid storage portion 160.

[0148] <Detailed configuration of the wick 130>

[0149] Figure 10 is a diagram showing the configuration of the wick 130.

[0150] Next, refer to Figure 10 to describe the configuration of the wick 130.

[0151] AsFigure 10 As shown, the wick 130 can be regarded as having a central portion 1311 in the width direction and end portions 1313 located at both ends in the width direction of the central portion 1311. Here, as described with reference to (D) of the above Figure 9 as described, the end portion 1313 is the portion of the wick 130 where the pressing process is performed. In this end portion 1313, the porosity is lower than that of the central portion 1311. In addition, in the end portion 1313, the effective pore diameter is smaller than that of the central portion 1311.

[0152] In this end portion 1313, since the voids formed in the wick 130 are smaller, for example, the contact area with the first side plate 111 becomes larger. That is, the wick 130 can increase the heat receiving area from the heating element. In addition, since the wick 130 is a porous metal, its shape is more likely to change by pressing than in the case of a non-porous metal.

[0153] In addition, as described above, after the end portion 1313 is compressed due to pressing, as a result, the porosity is smaller than that of the central portion 1311. Therefore, the behavior of the working fluid in the end portion 1313 may be different from that of the central portion 1311. Therefore, in the illustrated example, the area (size) of the compressed end portion 1313 is suppressed. Specifically, each one of the plurality of wick claw portions 133 provided on the wick 130 located at both ends in the width direction is pressed. Thereby, a larger non-pressed area can be ensured in the wick 130.

[0154] <Configuration of the support column 210>

[0155] Figure 11 is a diagram showing the configuration of the support column 210.

[0156] Next, with reference to Figure 11 , the configuration of the support column 210 will be described. It should be noted that in the following description, the support column 210 formed on the condenser 107 will be described.

[0157] The support column 210 is a component (so-called columnar) that supports the interior of the condenser 107. In the illustrated example, the support column 210 is a columnar body with a substantially elliptical cross-section. In addition, the support column 210 in the illustrated example is arranged in a prescribed configuration. To explain further, in the illustrated example, a combination of two support columns 210 and one support column 210 is arranged at every first interval L2 along the transfer direction. More specifically, the arrangement of one support column 210 (the first support column 2101) formed at the center in the width direction of the condenser 107 and the arrangement of two support columns 210 (the second support column 2102 and the third support column 2103) formed across the center in the width direction are repeated along the transfer direction. Here, the second support column 2102 and the third support column 2103 are formed at a prescribed interval, i.e., the second interval D2, from the support column 210 at the center in the width direction. In addition, the second support column 2102 and the third support column 2103 are respectively formed at a distance D3, which is 1 / 4 of the width direction length D4 of the condenser 107, from the inner walls 1071 and 1073 of the condenser 107.

[0158] Here, the configuration of the support column 210 will be further explained. The width direction length D1 of the support column 210 is, for example, 0.25 mm. It should be noted that this width direction length D1 is wider than the plate thickness of 0.15 mm of the first side plate 111 and the second side plate 121. In this way, by making the width direction length D1 of the support column 210 longer than the plate thickness of the first side plate 111 and the second side plate 121, the strength of the support column 210 is ensured.

[0159] In addition, the transfer direction length L1 of the support column 210 is 1.1 mm. The transfer direction length L1 of the support column 210 is longer than the width direction length D1. Thereby, the support column 210 can guide the working fluid. Here, if the transfer direction length L1 of the support column 210 is longer than a prescribed length, the joint strength after laser welding will increase. For example, as in the example of (C) above Figure 9 when joining the support column 210 by heating by irradiating the laser LA on the outer sides of the first side plate 111 and the second side plate 121, heating is performed while moving the irradiation position of the laser LA along the transfer direction (details will be described later). In the heating process by this laser LA, the output of the laser LA at the timing of starting the irradiation of the laser LA and the timing of ending the irradiation of the laser LA may become unstable. Therefore, by making the transfer direction length L1 of the support column 210 longer than a prescribed length, even when the irradiation position of the laser LA is moved along the transfer direction, the joining of the support column 210 can be made more reliable.

[0160] On the other hand, when the transfer direction length L1 of the support column 210 becomes longer, the irradiation time of the laser LA becomes longer, and the thermal deformation of the first side plate 111 and the second side plate 121 becomes larger. In the illustrated example, since the first side plate 111 and the second side plate 121 are thin plates, the deformation of the first side plate 111 and the second side plate 121 caused by the irradiation of the laser LA is more likely to occur. In the illustrated example, by making the transfer direction length L1 smaller than the second interval D2, the heat generated by the laser LA is reduced.

[0161] In addition, when the transfer direction length L1 of the support column 210 becomes longer, the flow path of the working fluid in the width direction becomes a state of being divided into multiple paths. Thus, when multiple flow paths are formed, the pressure in the flow path becomes different according to the flow path, and in some flow paths, the reverse flow of the working fluid may occur, etc., which may hinder the flow of the working fluid. In the illustrated example, by making the transfer direction length L1 of the support column 210 smaller than the second interval D2, the situation where the flow of the working fluid is hindered is suppressed.

[0162] It should be noted that in the width direction, the second interval D2 between the first support column 2101 and the second support column 2102 (third support column 2103) is 1.4 mm. In addition, in the transfer direction, the first interval L2 between the first support column 2101 and the second support column 2102 (third support column 2103) is 3.9 mm. This first interval L2 is shorter than 6 mm, which is the width direction length D4 of the condenser 107. Thus, the distance that the working fluid can freely move in the transfer direction is shorter than the distance in the width direction. In the illustrated example, the first interval L2 is longer than the transfer direction length L1 of the support column 210. Thus, the working fluid is allowed to move in the width direction.

[0163] In addition, when the volume of the support column 210 occupying the interior of the housing 100 increases, the flow path of the working fluid decreases. In addition, the presence of the support column 210 becomes a flow path resistance of the working fluid. Therefore, it is preferable to suppress the size and the number of the support columns 210. On the other hand, as the arrangement of the support columns 210, the support columns 210 are arranged in a dispersed manner, that is, the unevenness of the support columns 210 is suppressed, and thus, the interior of the housing 100 is supported more reliably. In the illustrated example, the support columns 210 are arranged in a pattern of two and one in the transfer direction. Thus, by arranging the support columns 210 regularly, the strength of the housing 100 is ensured. In addition, by arranging the support columns 210 regularly, the processing process of the support columns 210 is simplified, and the volume inside the housing 100 is ensured. It should be noted that the process of forming the support columns 210 (the first support column portion 211 and the second support column portion 221) on the first side plate 111 and the second side plate 121 is not particularly limited. For example, as described above Figure 7 of (B) and Figure 8As shown in (B) etc., by covering the region where the first support column portion 211 is formed with the first masking member M11, the first support column portion 211 etc. can be formed by etching together with the first support body 1123 and the second support body 1124. In addition, the first support column portion 211 etc. can be formed by etching in a process different from that of the first support body 1123 and the second support body 1124, or the first support column portion 211 etc. can be formed by laser processing etc.

[0164] <Process of forming support column 210>

[0165] Figure 12 It is a diagram showing the process of forming the support column 210.

[0166] It should be noted that in Figure 12 , the dimensions in the vertical direction of each component are described in a particularly emphasized (magnified) manner. In addition, Figure 12 (A) of Figure 9 shows the configuration around the first support column portion 211 and the second support column portion 221 in the process shown in (A) of Figure 12 . That is, Figure 9 (A) of Figure 12 corresponds to the process shown in (A) of Figure 9 . Similarly, Figure 12 (B) of Figure 9 corresponds to the process shown in (B) of Figure 12 (C) of Figure 9 corresponds to the process shown in (C) of

[0167] Next, referring to Figure 12 , the process of forming the support column 210 in the present embodiment will be described.

[0168] First, as shown in (A) of Figure 12 , the first side plate 111 and the second side plate 121 are overlapped. As a result, the first support column portion 211 and the second support column portion 221 formed on the first side plate 111 and the second side plate 121 respectively are in a mutually opposed configuration. And, as shown in (B) of Figure 12 , the top end of the first support column portion 211 and the top end of the second support column portion 221 are in a butted state.

[0169] Next, as shown in (C) of Figure 12 , a laser LA is irradiated from the outside of the first side plate 111 and the second side plate 121 to heat the first support column portion 211 and the second support column portion 221. In this process, the irradiation position of the laser LA moves along the transfer direction (refer to arrow M1). By this movement of the irradiation position of the laser LA, it is possible to heat the entire length direction of the first support column portion 211 and the second support column portion 221 that are long in the transfer direction. And, asFigure 12 As shown in (D), a part of the first support portion 211 and the second support portion 221 is melted to form a joint portion 231, whereby the first support portion 211 and the second support portion 221 are in a connected state. That is, the support 210 is formed.

[0170] <Wing portion 310>

[0171] Figure 13 It is a diagram showing the configuration of the wing portion 310.

[0172] Next, with reference to Figure 13 the configuration of the wing portion 310 will be described.

[0173] First, the wing portion 310 is a sealed configuration of the loop heat pipe 1. The wing portion 310 has: a wing body 311, which is a plate-like member having a substantially rectangular shape; and a notch 313, which is formed at the root of the wing body 311.

[0174] As described above, the manufacturing process of the loop heat pipe 1 includes a filling process, which is a process of filling the working fluid in the housing 100 (the first side plate 111 and the second side plate 121). After this filling process, a part of the wing portion 310 is sealed and cut off.

[0175] First, the filling process will be described. A metal pipe (not shown) constituting the flow path of the working fluid is connected to the first opening region 119. Specifically, in a state where the metal pipe is connected to the first opening region 119, a configuration in which the metal pipe is inserted between the two wing bodies 311 is formed. At this time, the wing body 311 presses the metal pipe, and the metal pipe is inhibited from falling off from the first opening region 119.

[0176] Next, the process of sealing and cutting off the wing portion 310 is as follows. First, a part of the wing body 311 is pressed (flattened) with an imaginary line A1 passing through the root of the wing body 311. That is, so-called riveting is performed at the root of the wing body 311. And the peripheral region A2 of the first opening region 119 is welded by laser. That is, laser welding is further performed on the riveted region. Thereby, the sealing becomes more reliable. And at the position along the imaginary line A1, the wing body 311 is cut off by a known cutting technique such as stamping or laser processing. It should be noted that by cutting off the wing body 311 after filling the working fluid, the shape of the loop heat pipe 1 is simplified.

[0177] <Electronic device>

[0178] Figure 14 It is a diagram showing a device including the loop heat pipe 1.

[0179] Next, with reference to Figure 14 , a device including the loop heat pipe 1 will be described.

[0180] As shown in Figure 14 (A) of FIG. 1, the loop heat pipe 1 is provided in an electronic device such as a mobile phone 800. The illustrated mobile phone 800 is a so-called smart phone. The mobile phone 800 includes: a central processing unit (CPU) 801 as an example of a heat generating body; and a loop heat pipe 1 that cools the CPU 801. Further, the heat generated by the CPU 801 is controlled by the loop heat pipe 1. The mobile phone 800 is manufactured by disposing the CPU 801 in the loop heat pipe 1.

[0181] Here, as described above, the loop heat pipe 1 does not require power supply from the outside. That is, the loop heat pipe 1 can operate without power. Further, the loop heat pipe 1 can perform long-distance heat transfer (for example, 100 mm to 1 m, etc.) and highly efficient heat transfer using latent heat. Further, the loop heat pipe 1 has a thin thickness and is also advantageous in terms of layout.

[0182] It should be noted that in recent years, due to the introduction of the so-called fifth-generation mobile communication system (5G), etc., the demand for high-frequency communication (3.7 GHz, 4.5 GHz, 28 GHz) has been increasing. And, in smart phones such as the mobile phone 800 and tablet terminals, for example, densification by adding components, an increase in the required values of the processing capabilities of the CPU and GPU, an increase in the heat generation density, and an increase in heat transfer are required. The loop heat pipe 1 described above is a device that can meet these required performances.

[0183] Here, as an example of an electronic device, the mobile phone 800 has been described, but the above loop heat pipe 1 can also be provided in a personal computer (PC), a tablet-type terminal, a projector, etc. Further, the loop heat pipe 1 can also be provided in an electronic control unit (Electronic Control Unit, ECU) and a battery mounted on an automobile, or various devices such as a satellite.

[0184] Here, as shown in Figure 14 (B) of FIG. 1, the loop heat pipe 1 can also be provided in a card 900 as an example of a device. It should be noted that the illustrated card 900 is called a so-called smart card, and its specifications are defined by an international standard (ISO / IEC7810).

[0185] Smart cards are mainly divided into contact type and non-contact type. Devices with a thickness of less than 0.4 mm are embedded inside the card as needed. For example, integrated circuit (IC) chips, near-field communication (NFC) antennas, Bluetooth (registered trademark) communication, fingerprint authentication sensors, displays, power ICs, DC / DC converters, batteries, capacitors, etc. In addition, in the future, with the advancement of the high performance of IC chips and various devices, the PCization of smart cards can be expected. The driving power for the PC is powered through the card reader 950 in the contact case and through the NFC antenna in the non-contact case. And, as the operating speed of the PC CPU 901 increases, the heat generation will increase, so a cooling mechanism needs to be set inside the card 900.

[0186] The loop heat pipe 1 has a thickness of, for example, 0.3 mm, so it can be embedded inside the card 900. In addition, the loop heat pipe 1 can also dissipate heat by exposing a part of the surface (condensing surface, etc.) of the condenser 107 to the outside of the card 900. To explain further, in the design where the card 900 is of the contact type and the PC CPU 901 has to be arranged inside the card reader 950, the loop heat pipe 1 can be effective. It should be noted that for the through hole 218 of the loop heat pipe 1 in the illustrated example, components required for the smart card, etc. can also be arranged. Such components are, for example, batteries, CPUs, random access memories (RAMs), read-only memories (ROMs), coprocessors, EEPROMs (non-volatile memories), and interfaces (I / Fs), etc. The size of this through hole is, for example, 38 mm in length in the width direction and 27 mm in length in the transfer direction.

[0187] <Modified Example>

[0188] Figure 15 This is a diagram showing a modified example of the present embodiment.

[0189] Next, with reference to Figure 15 , a modified example of the present embodiment will be described. It should be noted that in the following description, the same reference numerals are given to the parts having the same configuration as those in the above embodiment, and the detailed description thereof may sometimes be omitted.

[0190] In the description of (B) etc. of the above Figure 5 , it has been described that the thickness of the second support body 1124 etc. formed outside the first recess 110 of the first side plate 111 is thicker than the central side of the first recess 110, but this is not limited thereto. For example, as Figure 15As shown in (A), the thickness of the first side plate 1120 may be consistent on the outside and the center of the first recess 1110. It should be noted that in the example shown in the figure, the thickness of the second side plate 1220 is also consistent on the outside and the center of the first recess 1110. In addition, the liquid absorbent core 1130 is arranged in the first recess 1110.

[0191] In addition, in the above Figure 5 In the description of (B) and the like, a case where a step shape such as the second support body 1124 is formed outside the first recess 110 formed on the first side plate 111 is described, but the present invention is not limited thereto. Figure 15 As shown in (B), the bottom surface 2111 of the first concave portion 2110 formed in the first side plate 2120 may be curved. It should be noted that in the example shown in the figure, the bottom surface 2221 of the first concave portion 2110 formed in the second side plate 2220 is also curved. In addition, the liquid absorbent core 2130 is arranged in the first concave portion 2110.

[0192] In addition, in the above Figure 9 In the description of (E) and the like, it is described that the area where the first support body 1123 and the third support body 1223 are opposed to each other in the first side plate 111 and the second side plate 121 and the area where the second support body 1124 and the fourth support body 1224 are opposed to each other are pressurized. Here, as long as the outer side of the first recessed portion 1110 is pressurized, a structure without the first support body 1123 to the fourth support body 1224 may be used. For example, Figure 15 As shown in (C), the bottom surface 3111 of the first recessed portion 3110 formed in the first side plate 3120 may be flat. It should be noted that in the example shown in the figure, the bottom surface 3221 of the first recessed portion 3110 formed in the second side plate 3220 is also flat. In addition, the absorbent core 3130 is arranged in the first recessed portion 3110, and the end of the absorbent core 3130 is pressurized together with the first side plate 3120 and the second side plate 3220, thereby forming the first groove 1127 and the second groove 1128.

[0193] It should be noted that, in the above description, the first side plate 3120 and the second side plate 3220 are sandwiched from both sides, and the first groove 1127 or the second groove 1128 is formed on both the first side plate 3120 and the second side plate 3220, but it is not limited to this. For example, it can also be a scheme as follows: either one of the first side plate 3120 and the second side plate 3220 is pressed against a flat surface, and the outer side of the first recessed portion 1110 in the other side is pressurized. In this scheme, the first groove 1127 and the first groove 1227 or the second groove 1128 and the second groove 1228 are formed on one of the first side plate 3120 and the second side plate 3220.

[0194] <Other Modification Examples>

[0195] In the description of the above-mentioned Figure 9 (D), the case of pressing a part (specific area) of the first side plate 111 and the second side plate 121 was described. Here, as long as the gap GA can be reduced and the gap can be narrowed, it may also be a configuration in which the entire surfaces of the first side plate 111 and the second side plate 121 are pressed. In addition, as long as the gap GA is below a specified size, there may also be no process of pressing the first side plate 111 and the second side plate 121.

[0196] In addition, in the above description, the case of forming the support column 210 by heating the top of the first support column portion 211 and the top of the second support column portion 221 by laser welding or the like was described, but it is not limited thereto. For example, it may also be a configuration in which the top of the first support column portion 211 and the top of the second support column portion 221 are joined using other members such as an adhesive. In addition, it may also be a configuration in which only the top of the first support column portion 211 and the top of the second support column portion 221 are in contact without being joined.

[0197] In addition, in the above description, the case where the cross section of the support column 210 is a columnar body with a substantially elliptical shape was described, but as long as it is a protrusion that can support the space between the first side plate 111 and the second side plate 121, the shape is not particularly limited. For example, the cross section of the support column 210 may be a polygon such as a substantially rectangular parallelepiped, or it may be a circle.

[0198] In addition, in the above description, the case where the support column 210 is provided in the evaporator 101, the steam pipe 105, the condenser 107, and the liquid pipe 109 was described, but it is not limited thereto. For example, it may also be a configuration in which the support column 210 is provided in any one of the evaporator 101, the steam pipe 105, the condenser 107, and the liquid pipe 109. In addition, it may also be a configuration in which the support column 210 is not provided in any of the evaporator 101, the steam pipe 105, the condenser 107, and the liquid pipe 109.

[0199] In addition, in the above-mentioned Figure 4 etc., the case where the wick 130 has a wick convex portion 137 at the central portion in the width direction of the wick base portion 131 was described, but it is not limited thereto. It may also be a configuration in which the wick convex portion 137 is provided closer to the end side of the wick base portion 131 in the width direction. In addition, it may also be a configuration in which the wick 130 does not have the wick convex portion 137. In addition, the above-mentioned Figure 4The liquid absorption core convex portion 137 shown in the figure is substantially rectangular in a top view, but it is not limited to this as long as the supply of the working fluid to the liquid absorption core base portion 131 is promoted. For example, it may also be configured such that the width of the liquid absorption core convex portion 137 increases as it goes downstream in the transfer direction. In addition, it may also be configured such that the liquid absorption core convex portion 137 is bent. In addition, it may also be configured to have a plurality of liquid absorption core convex portions 137.

[0200] In addition, in the above description, the case where the effective void diameter of the liquid absorption core 130 is 0.1 μm to 50 μm or the like is described, but it is not limited to this. For example, in the case where the liquid absorption core 130 is a dual-porosity liquid absorption core having different characteristic pore diameters, the peak value on the side with the smaller effective void diameter may also be 3.5 μm to 49 μm. In addition, it may also be configured such that the effective void diameters of the liquid absorption core base portion 131, the liquid absorption core claw portion 133, and the liquid absorption core convex portion 137 are different from each other. For example, it may also be configured such that the liquid absorption core 130 has: a liquid absorption core base portion 131 and a liquid absorption core claw portion 133 with a first opening diameter; and a liquid absorption core convex portion 137 with a second average opening diameter different from the first opening diameter (larger than the first opening diameter).

[0201] In addition, in the above description, the case of using the mask 180 and coating the liquid absorption core 130 is described, but it is not limited to this. For example, it may also be the following scheme: using a known technique such as a screen for screen printing, a dispenser, or a masking tape 280 instead of the mask 180 to pre-coat the liquid absorption core 130 onto a predetermined area. In addition, it may also be: after forming a sheet-like (thin plate-like) liquid absorption core member by a coater, cutting it into a specified shape to form the liquid absorption core 130. Similarly, the method of forming the coating of the joining member 150 is not limited either.

[0202] In addition, in the above description, the case of forming the liquid absorption core 130 by coating is described, but the forming method of the liquid absorption core 130 is not limited to this. For example, it may also be: disposing the material of the liquid absorption core 130 in a powder state on the first side plate 111 and forming the liquid absorption core 130 by sintering. For example, it may also be the following scheme: spreading a powder material with a thickness of about 0.3 mm at the position where the liquid absorption core 130 is to be formed on the first side plate 111. In addition, the liquid absorption core 130 may also be formed by etching fine holes in a plate-like member. It should be noted that, as in the above-described embodiment, by combining the powder material with a binder to form a paste, the material of the liquid absorption core 130 can be thinly and evenly coated.

[0203] In addition, the material constituting the liquid absorption core 130 is not limited to the above-mentioned porous body made of metal. As long as it can be processed into powder and the positions of each other can be fixed by heating, it may also be other materials such as ceramic porous bodies, glass porous bodies, and porous fibers.

[0204] In addition, in the above description, the case of forming the first recess 110, the second recess 120, etc. by etching has been described, but it is not limited thereto. For example, the first recess 110 and the second recess 120 can also be formed by performing known processing such as cutting and stamping on the first side plate 111 and the second side plate 121. In addition, as long as a space for disposing the liquid absorption core 130 and the joining member 150 can be formed between the first side plate 111 and the second side plate 121, it can also be a configuration in which only one of the first recess 110 and the second recess 120 is formed. It should be noted that, as described above, by etching the first recess 110 to roughen the first bottom surface 114, the liquid absorption core 130 can be more reliably fixed to the first side plate 111. In addition, by etching the second recess 120 to roughen the second bottom surface 124, the joining member 150 can be more reliably fixed to the second side plate 121.

[0205] In addition, the first side plate 111 and the second side plate 121 only need to be configured to suppress the size in the thickness direction, and are not limited to a substantially plate-like shape. For example, the first side plate 111 and the second side plate 121 can be configured with concavities and convexities formed on their plate surfaces, or with other members fixed on their plate surfaces. In addition, the first side plate 111 and the second side plate 121 can be regarded as a main body and a cover body covering the main body, respectively. In addition, the loop heat pipe 1 can also be formed by sandwiching a frame body separated from the first side plate 111 and the second side plate 121 between the first side plate 111 and the second side plate 121.

[0206] In addition, in the above description, the case where the joining member 150 is formed by sintering after applying the material of the joining member 150 has been described, but it is not limited thereto. For example, it can also be the following configuration: the joining member 150 is pre-formed as a plate-like member, and the plate-like joining member 150 is heated in a state where it is sandwiched between the second side plate 121 and the liquid absorption core 130, whereby the plate-like joining member 150 is fixed to the second side plate 121 and the liquid absorption core 130. In addition, different from the illustrated example, it can also be a configuration in which the joining member 150 is not provided.

[0207] In addition, in the above description, the case of joining the first side plate 111 and the second side plate 121 with a laser has been described, but it is not limited thereto. For example, as long as the inflow of solder and brazing material into the first recess 110 and the second recess 120 can be suppressed, the first side plate 111 and the second side plate 121 can also be joined by welding or brazing. In addition, as long as the blockage of the flow path can be prevented, diffusion bonding can also be used. In addition, the joining can also be performed by using adhesive bonding, ultrasonic bonding, friction stir bonding, etc.

[0208] In addition, in the above description, the loop heat pipe 1 has been described as a heat exchanger, but as long as it is a two-phase heat transfer device, there is no particular limitation. For example, in other heat exchangers such as a heat spreader, the above-described configurations such as the wick 130 and the first side plate 111 can also be employed.

[0209] Then, the above-described various embodiments and modification examples have been described, but of course, these embodiments and modification examples can be combined with each other to form a configuration.

[0210] In addition, the present disclosure is not limited to any of the above-described embodiments, and can be implemented in various forms without departing from the gist of the present disclosure.

[0211] The loop heat pipe 1 is an example of a heat exchanger. The wick 130 is an example of an evaporator. The first side plate 111 is an example of a main body. The second side plate 121 is an example of a cover. The first recess 110 is an example of a recess. The first support 1123 is an example of a structural part. The first conical surface 1125 is an example of an inclined surface. The first metal paste 149 is an example of a material. The mobile phone 800 is an example of a device. The heating element 10 is an example of a heating component.

[0212] Description of Reference Numerals

[0213] 100: Loop heat pipe; 110: First recess; 111: First side plate; 121: Second side plate; 130: Wick; 149: First metal paste; 180: Mask; 1123: First support; 1127: First groove.

Claims

1. A heat exchanger having an evaporator provided with an evaporation body that absorbs heat from the outside and evaporates into a gas phase while causing a working fluid in a liquid phase to move by capillary force, the heat exchanger condensing the working fluid in the gas phase derived from the evaporator and returning it as a working fluid in the liquid phase to the evaporator, wherein, the evaporator has: a main body, which is a plate-like member, and a recess for providing the evaporation body is formed on the plate surface of the main body; and a cover body that covers the recess of the main body and the evaporation body provided in the recess, the main body has a structural portion in which the depth of the outside of the recess is shallower than the depth of the central side of the recess, the outside of the evaporation body provided in the recess is sandwiched between the structural portion and the cover body.

2. The heat exchanger according to claim 1, wherein, the structural portion is a portion in the recess where the thickness is thicker than the thickness of the bottom of the central side.

3. The heat exchanger according to claim 2, wherein, the structural portion is a step formed at an end portion in the crossing direction of the evaporation body, and the crossing direction is a direction crossing the direction of flow of the working fluid, that is, the flow direction.

4. The heat exchanger according to claim 3, wherein, an inclined surface is provided at a position on the upstream side in the flow direction with respect to the structural portion, and the inclined surface is inclined toward the central side in the crossing direction as it goes toward the downstream side in the flow direction.

5. The heat exchanger according to any one of claims 1 to 4, wherein, the effective pore diameter of the pores formed in the evaporation body is 3.5 μm to 49 μm.

6. The heat exchanger according to claim 5, wherein, the effective pore diameter of the outside of the evaporation body is smaller than the effective pore diameter of the central side.

7. A heat exchanger having an evaporator provided with an evaporation body that absorbs heat from the outside and evaporates into a gas phase while causing a working fluid in a liquid phase to move by capillary force, the heat exchanger condensing the working fluid in the gas phase derived from the evaporator and returning it as a working fluid in the liquid phase to the evaporator, wherein, the evaporator has: a main body, which is a plate-like member, and a recess for providing the evaporation body is formed on the plate surface of the main body; and a cover body that covers the recess of the main body and the evaporation body provided in the recess, a pressing mark obtained by pressing the main body, the cover body, and the evaporation body is formed at a position on the plate surface of at least one of the main body and the cover body that is closer to the outside than the center of the recess.

8. A manufacturing method, which is a manufacturing method of a heat exchanger having an evaporator provided with an evaporation body that absorbs heat from the outside and evaporates into a gas phase while causing a working fluid in a liquid phase to move by capillary force, the heat exchanger condensing the working fluid in the gas phase derived from the evaporator and returning it as a working fluid in the liquid phase to the evaporator, wherein, the evaporator has: a main body, which is a plate-like member, and a recess for providing the evaporation body is formed on the plate surface of the main body; and A cover body that covers the concave portion of the main body and the evaporation body provided in the concave portion The manufacturing method includes the following steps: Form the concave portion in the main body and form a structural portion in which the depth of the outer side of the concave portion is shallower than the depth of the central side of the concave portion; Apply the material of the evaporation body in the concave portion and solidify the material to form the evaporation body; and Cover the concave portion provided with the evaporation body with the cover body, and sandwich the outer side of the evaporation body provided in the concave portion between the structural portion and the cover body.

9. The manufacturing method according to claim 8, including the following steps: Press the outer side of the evaporation body sandwiched between the structural portion and the cover body together with the main body and the cover body.

10. The manufacturing method according to claim 8 or 9, wherein The structural portion is a portion in the concave portion where the thickness is thicker than the thickness of the bottom of the central side.

11. The manufacturing method according to claim 10, wherein The structural portion is a step formed at the end in the crossing direction of the bottom of the concave portion, and the crossing direction is a direction crossing the flow direction, which is the direction in which the working fluid flows in the evaporation body.

12. The manufacturing method according to claim 11, wherein An inclined surface is provided at a position on the upstream side of the flow direction with respect to the step, and the inclined surface inclines toward the central side in the crossing direction as it goes to the downstream side of the flow direction.

13. The manufacturing method according to claim 8, wherein The effective pore diameter of the pores formed in the evaporation body is 3.5 μm to 49 μm.

14. The manufacturing method according to claim 13, wherein The effective pore diameter of the outer side of the evaporation body is smaller than the effective pore diameter of the central side.

15. A manufacturing method is a manufacturing method of a heat exchanger. The heat exchanger has an evaporator. The evaporator is provided with an evaporation body that absorbs heat from the outside and evaporates into a gas phase while moving a liquid-phase working fluid by capillary force. The heat exchanger condenses the gas-phase working fluid derived from the evaporator and returns it as a liquid-phase working fluid to the evaporator. Among them, The evaporator has: A main body, which is a plate-shaped member, and a concave portion for providing the evaporation body is formed on the plate surface of the main body; and A cover body that covers the concave portion of the main body and the evaporation body provided in the concave portion The manufacturing method includes the following steps: Form the concave portion in the main body; Form a structural portion in which the depth of the outer side of the concave portion is shallower than the depth of the central side of the concave portion and the thickness of the bottom of the outer side of the concave portion is thicker than the thickness of the bottom of the central side of the concave portion; Apply the material of the evaporation body in the concave portion and solidify the material to form the evaporation body; Cover the concave portion provided with the evaporation body with the cover body; and Clamp the regions of the plate surfaces of the main body and the cover body covering the main body where the outer side of the evaporation body provided in the concave portion is located, and compress the evaporation body through the structural portion and the cover body.

16. A device, the device includes: A heating element; and A heat exchanger having an evaporator provided with an evaporation body that absorbs heat from the heat generating body and evaporates into a gas phase while causing a working fluid in a liquid phase to move by capillary force, the heat exchanger condensing the gas-phase working fluid derived from the evaporator and returning it as a liquid-phase working fluid to the evaporator, wherein, The evaporator has: A main body, which is a plate-shaped member, and a recess for arranging the evaporation body is formed on the plate surface of the main body; and A cover body covering the recess of the main body and the evaporation body arranged in the recess, The main body has a structural part that makes the depth of the outside of the recess shallower than the depth of the central side of the recess, The outside of the evaporation body arranged in the recess is clamped between the structural part and the cover body.

17. A heat exchanger having an evaporator provided with an evaporation body that absorbs heat from the outside and evaporates into a gas phase while causing a working fluid in a liquid phase to move by capillary force, the heat exchanger condensing the gas-phase working fluid derived from the evaporator and returning it as a liquid-phase working fluid to the evaporator, wherein, The evaporator has: A main body, which is a plate-shaped member, for arranging the evaporation body, and a flow path for the working fluid is formed on the plate surface of the main body; A cover body covering the evaporation body and the flow path arranged on the main body; And A guiding part arranged at the bottom of the flow path, supporting the main body and the cover body in the flow path, and formed with its long dimension direction along the flow direction of the working fluid flow, the guiding part guiding the working fluid, The length of the guiding part in the flow direction is shorter than the length of the flow path in the width direction.

18. The heat exchanger according to claim 17, wherein, A plurality of the guiding parts are arranged at regular intervals along the flow direction.

19. The heat exchanger according to claim 18, wherein, The regular interval is longer than the length of the guiding part in the flow direction.

20. The heat exchanger according to claim 17, wherein, In the guiding part, a plurality of groups of the guiding parts with different positions in the width direction are arranged side by side in the flow direction.

21. The heat exchanger according to claim 17, wherein, The length of the guiding part in the width direction is longer than the thickness of the main body.

22. The heat exchanger according to claim 17, wherein, The guiding part connects the main body and the cover body in the thickness direction of the main body.

23. The heat exchanger according to claim 22, wherein, The guiding part is heated by a heating part that moves along the flow direction outside the main body and the cover body and heats the guiding part, thereby connecting the main body and the cover body.

24. The heat exchanger according to claim 17, wherein, The guiding part is arranged inside the evaporator provided with the evaporation body.

25. The heat exchanger according to claim 17 has: A condenser that condenses the gas-phase working fluid flowing out from the evaporator and returns it to the evaporator, The guiding part is arranged inside the condenser.

26. The heat exchanger according to any one of claims 17 to 25, wherein the effective pore diameter of the pores formed in the evaporation body is 3.5 μm to 49 μm.

27. A heat exchanger having an evaporator provided with an evaporation body that absorbs heat from the outside and evaporates into a gas phase while causing a working fluid in a liquid phase to move by capillary force, the heat exchanger condensing the working fluid in the gas phase derived from the evaporator and returning it as a working fluid in the liquid phase to the evaporator, wherein the evaporator has: a main body, which is a plate-shaped member on which the evaporation body is provided, and a flow path for the working fluid is formed on the plate surface of the main body; a cover body that covers the evaporation body and the flow path provided on the main body; and a guiding portion provided at the bottom of the flow path, supporting the main body and the cover body in the flow path, and formed with its long dimension direction along the flow direction of the working fluid, the guiding portion guiding the working fluid, the length of the guiding portion in the flow direction is shorter than the length of the flow path in the width direction, the length of the guiding portion in the width direction is longer than the thickness of the main body, the guiding portion is provided in the flow path at a plurality of prescribed intervals along the flow direction and is provided at positions different from each other in the width direction according to the position in the flow direction, the prescribed interval is longer than the length of the guiding portion in the flow direction.

28. A manufacturing method for manufacturing a heat exchanger having an evaporator provided with an evaporation body that absorbs heat from the outside and evaporates into a gas phase while causing a working fluid in a liquid phase to move by capillary force, and the heat exchanger condensing the working fluid in the gas phase derived from the evaporator and returning it as a working fluid in the liquid phase to the evaporator, wherein the evaporator has: a main body, which is a plate-shaped member on which the evaporation body is provided, and a flow path for the working fluid is formed on the plate surface of the main body; a cover body that covers the evaporation body and the flow path provided on the main body; and a guiding portion provided at the bottom of the flow path, supporting the main body and the cover body in the flow path, and formed with its long dimension direction along the flow direction of the working fluid, the guiding portion guiding the working fluid, the length of the guiding portion in the flow direction is shorter than the length of the flow path in the width direction, the manufacturing method includes the following steps: forming the flow path and the guiding portion in the main body; covering the evaporation body and the flow path provided on the main body with the cover body; and heating the guiding portion by a heating portion to connect the main body and the cover body in the thickness direction of the main body, wherein the heating portion moves along the flow direction outside the main body and the cover body and heats the guiding portion, and the guiding portion supports the main body and the cover body in the flow path.

29. A device comprising: a heating element; and A heat exchanger having an evaporator provided with an evaporation body that absorbs heat from the heating body and evaporates into a gas phase while causing a working fluid in a liquid phase to move by capillary force, the heat exchanger condensing the working fluid in a gas phase derived from the evaporator and returning it as a working fluid in a liquid phase to the evaporator, wherein, the evaporator has: a main body, which is a plate-shaped member on which the evaporation body is provided, and a flow path for the working fluid is formed on the plate surface of the main body; a cover body that covers the evaporation body and the flow path provided on the main body; and a guiding portion provided at the bottom of the flow path, supporting the main body and the cover body in the flow path, and formed with its long dimension direction along the flow direction of the working fluid, the guiding portion guiding the working fluid, the length of the guiding portion in the flow direction is shorter than the length of the flow path in the width direction.

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