Cooler

Abstract

A cooler (10) comprises: a base layer (1) to which an element is joined; a fin formation layer (2) that has a fin arrangement region (R20) in which a plurality of fins (21) that are connected to the base layer (1) are arranged; and an opening formation layer (3) that is connected to the fin formation layer (2) and has a plurality of fin inflow ports (31) and a plurality of fin outflow ports (32), through which a coolant flows into the fin arrangement region (R20). The plurality of fin inflow ports (31) are connected to an inflow port (71), into which the coolant flows, of the cooler (10) via an inflow channel. The plurality of fin outflow ports (32) are connected to an outflow port (72), from which coolant outflows, of the cooler (10) via an outflow channel. The plurality of fin inflow ports (31) and the plurality of fin outflow ports (32) are arranged alternately and in parallel to each other in the direction radially away from a point within a region where the shape of the element is projected to the opening formation layer (3).

Description

Technical Field

[0001] The present disclosure relates to a cooler that cools an element using a refrigerant circulated by a pump.

Background Art

[0002] Patent Document 1 discloses a cooler for cooling a conventional semiconductor power device. The cooler described in Patent Document 1 includes a substrate assembly in which a manifold layer, a channel layer, a ceramic layer, and a metal layer are laminated in this order and joined together, and a plenum housing having an inlet port and an outlet port. The manifold layer branches cooling water, which is a refrigerant from the inlet port of the plenum housing, into an inlet manifold, which is a plurality of flow paths, and supplies it to the channel layer. Further, the manifold layer receives the cooling water that has passed through the channel layer in an outlet manifold, which is a plurality of flow paths, and joins it to the outlet port of the plenum housing. In the manifold layer, an inlet manifold and an outlet manifold extending in the first direction are alternately provided at intervals defined in the second direction. The channel layer is a layer that supplies the cooling water from the manifold layer to channels extending in the second direction, and returns the cooling water that has flowed through the channels to the manifold layer again. In the channel layer, a plurality of channels extending in the second direction are provided at intervals defined in the first direction on the joint surface side with the manifold layer. The ceramic layer is made of a material having a high thermal conductivity. The metal layer is connected to the semiconductor power device to be cooled.

[0003] In the cooler described in Patent Document 1, when the cooling water flows in from the inlet port of the plenum housing, the cooling water flows through the channels of the channel layer via the inlet manifold of the manifold layer, and is discharged from the outlet port of the plenum housing via the outlet manifold of the manifold layer. Thereby, the heat from the semiconductor power device transmitted through the metal layer and the ceramic layer is removed by the cooling water flowing through the channel layer.

Prior Art Documents

Patent Documents

[0004] [Patent Document 1] Patent No. 5711459 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] In heating elements such as laser elements, where temperature dependence directly affects oscillation performance, a uniform temperature distribution is desirable. In such heating elements, the temperature distribution can be adjusted by changing the heat distribution through internal pattern design or current adjustment. However, designing with such temperature distribution adjustment in mind is not easy. Furthermore, for the sake of design simplification, it is preferable that the temperature distribution be concentric and small. However, in the conventional technology described above, the direction of cooling water flow in the channel layer in contact with the ceramic layer is unidirectional, in the direction of the channel formed to extend in the second direction. As a result, there was a problem in that the temperature distribution was not concentric, and the temperature changed significantly in the direction of the cooling water flow.

[0006] This disclosure has been made in view of the above, and aims to provide a cooler that can bring the temperature distribution generated by the cooler closer to concentric circles, and reduce the temperature distribution inside the element compared to conventional coolers. [Means for solving the problem]

[0007] To solve the above-mentioned problems and achieve the objective, the cooler according to this disclosure is a cooler that is bonded to an element and cools the element, comprising: a base layer to which the element is bonded; a fin forming layer having a fin arrangement region on which a plurality of fins connected to the base layer are arranged; and an opening forming layer connected to the fin forming layer and having a plurality of fin inlets and a plurality of fin outlets for flowing a refrigerant into the fin arrangement region. The plurality of fin inlets are connected to inlets through which the refrigerant of the cooler flows in via inflow channels. The plurality of fin outlets are connected to outlets through which the refrigerant of the cooler flows out via outflow channels. The plurality of fin inlets and the plurality of fin outlets are arranged alternately and in parallel in a direction radially away from a point in a region on which the shape of the element is projected onto the opening forming layer. [Effects of the Invention]

[0008] The cooler according to this disclosure has the effect of making the temperature distribution generated by the cooler closer to concentric circles, and reducing the temperature distribution inside the element compared to conventional coolers. [Brief explanation of the drawing]

[0009] [Figure 1] A schematic cross-sectional view showing an example of the configuration of the cooler according to Embodiment 1. [Figure 2] A top view showing the configuration of each layer of the cooler according to Embodiment 1, in an exploded view. [Figure 3] A diagram illustrating an example of refrigerant flow in a cooler according to Embodiment 1. [Figure 4] This figure shows an example of refrigerant flow in the opening forming layer of the cooler according to Embodiment 1. [Figure 5] This figure shows an example of the relationship between the opening-forming layer and the element arrangement region that constitute the cooler according to Embodiment 1. [Figure 6] Enlarged top view of a portion of the opening-forming layer [Figure 7] A top view showing another example of the configuration of the opening-forming layer constituting the cooler according to Embodiment 1. [Figure 8] A top view showing another example of the configuration of the opening-forming layer constituting the cooler according to Embodiment 1. [Figure 9] Top view showing another example of the configuration of the opening formation layer constituting the cooler according to Embodiment 1 [Figure 10] Top view showing another example of the configuration of the opening formation layer constituting the cooler according to Embodiment 1 [Figure 11] Top view showing another example of the configuration of the opening formation layer constituting the cooler according to Embodiment 1 [Figure 12] Top view schematically showing the positional relationship between the openings in the opening formation layer and the grooves in the fin arrangement region arranged in the fin formation layer [Figure 13] Partially enlarged top view showing an example of the configuration of the fin formation layer constituting the cooler according to Embodiment 1 [Figure 14] Top view showing another example of the configuration of the fin formation layer constituting the cooler according to Embodiment 1 [Figure 15] [[ID=二十]]Top view of a partially enlarged fin arrangement region of the fin formation layer of FIG. 14 [Figure 16] Top view showing an example of the configuration of the opening formation layer corresponding to the fin formation layer of FIG. 14 [Figure 17] Cross-sectional view schematically showing an example of the configuration of the cooler according to Embodiment 2 [Figure 18] Top view showing an example of the configuration of the flow path formation layer constituting the cooler according to Embodiment 2 [Figure 19] Figure showing an example of the state where the opening formation layer and the flow path formation layer are overlapped [Figure 20] Cross-sectional view schematically showing an example of the configuration of the cooler according to Embodiment 3 [Figure 21] Top view showing an example of the configuration of the flow path connection layer constituting the cooler according to Embodiment 3 [Figure 22] Top view showing an example of the configuration of the flow path distribution layer constituting the cooler according to Embodiment 3 [Figure 23] Top view showing an example of the configuration of the outflow / inflow port arrangement layer constituting the cooler according to Embodiment 3 [Figure 24] Top view showing an example of the configuration of the flow path connection layer constituting the cooler according to Embodiment 3

Mode for Carrying Out the Invention

[0010] Hereinafter, the cooler according to the embodiment of the present disclosure will be described in detail based on the drawings.

[0011] Embodiment 1. FIG. 1 is a cross-sectional view schematically showing an example of the configuration of a cooler according to Embodiment 1. The element 100 to be cooled is joined to the cooler 10 via a heat-conducting layer 101 having insulation properties. The element 100 is an element that generates heat due to the operation of a laser element or the like. The heat-conducting layer 101 is a layer that transfers heat from the element 100 to the cooler 10, and is a material having insulation properties and high thermal conductivity that easily transfers heat. The heat-conducting layer 101 and the element 100 are joined with a joining material. Examples of the heat-conducting layer 101 are ceramics such as aluminum nitride (AlN), aluminum oxide (Al2O3), AlSiC, and diamond. The heat-conducting layer 101 also serves to prevent the element 100 from being destroyed by stress generated during joining due to the difference in the coefficient of thermal expansion between the element 100 and the cooler 10. When the element 100 is not insulated by the heat-conducting layer 101, CuW, CuMo, etc. may be used to adjust the stress generated during joining due to the difference in the coefficient of thermal expansion. Also, when insulation is not required depending on the application and the difference in the coefficient of thermal expansion between the element 100 and the cooler 10 does not pose a problem, the element 100 may be directly joined onto the cooler 10 via a joining material without having the heat-conducting layer 101. Note that when the element 100 is disposed on the cooler 10 via the heat-conducting layer 101, the element 100 is energized by connecting a pattern formed by a thin film such as a copper (Cu) film formed on the heat-conducting layer 101 and electrodes around the element 100 via wire bonding or the like. The heat-conducting layer 101 is joined to the cooler 10 via a joining material in one example.

[0012] The cooler 10 is a device that is joined to the element 100 and cools the element 100 using a refrigerant circulated by a pump (not shown). The cooler 10 according to Embodiment 1 is broadly composed of seven metal layers. That is, the cooler 10 has, in order from the side where the element 100 is placed, a base layer 1, a fin-forming layer 2, an opening-forming layer 3, a flow-channel-forming layer 4, a flow-channel-forming layer 5, a flow-channel-connecting layer 6, and an inlet / outlet-arrangement layer 7. Each of these layers is composed of a metal layer. Each of these layers can be made of a metal with good thermal conductivity, such as Cu or Al (aluminum). Also, in this example, each layer of the cooler 10 is rectangular in shape. Here, the cooler 10 is divided into multiple layers focusing on the function of each metal layer, and it is not necessarily the case that the cooler 10 is composed of physically separated metal layers joined together. Also, one layer may be composed of multiple physically separated layers. In the following, the stacking direction of each metal layer is the Z-axis direction. Furthermore, the two positions along the Z-axis are expressed using relative vertical coordinates.

[0013] Next, the configuration of each layer constituting each cooler 10 will be described. Figure 2 is a top view showing the configuration of each layer of the cooler according to Embodiment 1 in an exploded view. Here, the origin is defined as the center of the projection region, which is the region obtained by projecting the area where the element 100 is placed onto the upper surface of the opening-forming layer 3. The X-axis is taken in a direction parallel to the long side of the rectangular opening-forming layer 3 passing through the origin, and the Y-axis is taken in a direction parallel to the short side of the rectangular opening-forming layer 3 passing through the origin. The X-axis, Y-axis, and Z-axis are assumed to be perpendicular to each other. However, this is just an example, and the X-axis and Y-axis can be set arbitrarily.

[0014] The base layer 1 is a metal layer on which the element 100 is placed either via or directly on the upper surface via the thermal conductive layer 101, and serves as a base plate. The base layer 1 is a flat metal layer. In the figure, region R100 indicates the element placement region where the element 100 is placed, and region R101 indicates the thermal conductive layer placement region where the thermal conductive layer 101 is placed. In this example, the element 100 is placed such that its center lies at the center of the base layer 1 in the XY plane within the element placement region R100. The thermal conductive layer placement region R101 includes the element placement region R100 and is larger than the element placement region R100.

[0015] The fin-forming layer 2 is a metal layer located on the lower surface of the base layer 1 and connected to the base layer 1. The fin-forming layer 2 has a plurality of fins 21 connected to the base layer 1 to improve cooling performance, in a region that includes at least the region onto which the element arrangement region R100 is projected. The region where the fins 21 are formed is called the fin arrangement region R20. In the fin arrangement region R20, in one example, a plurality of fins 21 are arranged periodically in a two-dimensional plane. Between the fins 21 are grooves 22 that serve as flow paths for the refrigerant. An example of a fin 21 is a pin fin that extends in the Z-axis direction and has one end connected to the base layer 1. Between the pin fins, grooves 22 are formed, which are openings with the pin fins as sidewalls. The grooves 22 on the lower surface of the metal layer constituting the fin-forming layer 2 are openings to the fin arrangement region R20 in the Z-axis direction. The region of the fin-forming layer 2 other than the fin arrangement region R20 is plate-like.

[0016] The base layer 1 and the fin-forming layer 2 can be manufactured using various methods. In one example, the base layer 1 and the fin-forming layer 2 can be integrally formed by etching grooves 22 from a single metal layer. Specifically, masks are formed on the lower surface of a single metal layer in areas other than the fin placement region R20, and at the pin fin formation positions within the fin placement region R20. Then, by etching the lower surface of the metal layer with the masks to a predetermined depth, grooves 22 are formed in the areas where the masks are not formed. In other words, in the fin placement region R20, grooves 22 are formed in the areas where the masks are not formed, leaving the areas where the masks are formed untouched. These remaining areas become pin fins extending in the Z-axis direction. By ending the etching at a position where the depth of the grooves 22 reaches a predetermined value, the area with the grooves 22 becomes the fin-forming layer 2, and the remaining area becomes the base layer 1. Thus, although the base layer 1 and the fin-forming layer 2 are shown as two separate layers in Figures 1 and 2 for illustrative purposes, they are manufactured from a single metal block. Note that the production of base layer 1 and fin-forming layer 2 by etching is just one example; they can also be produced by other methods. For example, base layer 1 and fin-forming layer 2 may be produced by die casting, or by cutting from a single metal component. Furthermore, as will be described later, they can also be produced by laminating metal layers.

[0017] The opening-forming layer 3 is a metal layer having openings that serve as fin inlets 31 and fin outlets 32 for supplying refrigerant to the fin arrangement region R20. The opening-forming layer 3 has a fin inlet 31 for supplying refrigerant to the fin arrangement region R20 and a fin outlet 32 ​​for discharging refrigerant from the fin arrangement region R20, in a region that includes at least the region onto which the element arrangement region R100 is projected. The fin inlets 31 and fin outlets 32, which are the openings, are arranged alternately and in parallel in a direction radially away from a point in the region onto which the element arrangement region R100 is projected. In this example, the point in the region onto which the element arrangement region R100 is projected is the origin. The fin inlets 31 and fin outlets 32 penetrate the metal layer in the Z-axis direction. Here, the fin inlets 31 and fin outlets 32 are constructed by connecting the respective ends of multiple openings that extend in different directions. Specifically, the fin inlet 31 and fin outlet 32 ​​are composed of openings in which an opening extending in the X-axis direction and an opening extending in the Y-axis direction are connected at their ends. The X-axis direction is an example of a first direction, and the Y-axis direction is an example of a second direction. The detailed structure of the openings in the opening-forming layer 3 will be described later. The opening-forming layer 3 is joined to the fin-forming layer 2 at its upper surface.

[0018] The flow channel forming layer 4 is a metal layer having a flow channel that guides refrigerant flowing in from the flow channel forming layer 5 to a predetermined opening in the opening forming layer 3, and guides refrigerant discharged from the predetermined opening in the opening forming layer 3 to the flow channel forming layer 5. The flow channel forming layer 4 has a refrigerant inflow flow channel 41 that forms part of the flow channel that sends refrigerant to the fin arrangement region R20, and a refrigerant outflow flow channel 42 that forms part of the flow channel that discharges refrigerant from the fin arrangement region R20. The refrigerant inflow flow channel 41 and the refrigerant outflow flow channel 42 penetrate the metal layer in the Z-axis direction. The flow channel forming layer 4 is joined to the opening forming layer 3 at its upper surface.

[0019] The flow path forming layer 5 is a metal layer having a flow path that guides refrigerant flowing in from the flow path connecting layer 6 to the refrigerant inflow flow path 41 of the flow path forming layer 4, and refrigerant discharged from the refrigerant outflow flow path 42 of the flow path forming layer 4 to the flow path connecting layer 6. The flow path forming layer 5 has a refrigerant inflow flow path 51 that forms part of the flow path that sends refrigerant to the fin arrangement region R20, and a refrigerant outflow flow path 52 that forms part of the flow path that discharges refrigerant from the fin arrangement region R20. The refrigerant inflow flow path 51 and the refrigerant outflow flow path 52 penetrate the metal layer in the Z-axis direction. The refrigerant inflow flow path 51 and the refrigerant outflow flow path 52 are composed of openings that extend in the X-axis direction. In addition, the refrigerant inflow flow path 51 and the refrigerant outflow flow path 52 are arranged alternately in the Y-axis direction. The refrigerant inflow flow path 51 and the refrigerant outflow flow path 52 have the same length, but are arranged so that the positions of their ends in the X-axis direction are different. In this example, the refrigerant inlet channel 51 and refrigerant outlet channel 52 are arranged such that at the first end, which is the positive end of the X-axis, the refrigerant inlet channel 51 protrudes more towards the positive X-axis than the refrigerant outlet channel 52, and at the second end, which is the negative end of the X-axis, the refrigerant outlet channel 52 protrudes more towards the negative X-axis than the refrigerant inlet channel 51. The region at the positive end of the X-axis where the position of the refrigerant inlet channel 51 does not overlap with the position of the refrigerant outlet channel 52 is called the refrigerant inlet region R53. The region at the negative end of the X-axis where the position of the refrigerant outlet channel 52 does not overlap with the position of the refrigerant inlet channel 51 is called the refrigerant outlet region R54. The channel forming layer 5 is joined to the channel forming layer 4 at its upper surface.

[0020] The flow path forming layers 4 and 5 correspond to the second flow path forming layer having refrigerant inflow channels 41, 51 and refrigerant outflow channels 42, 52. The flow path forming layer 5 has the role of transporting the refrigerant in the X-axis direction, while the flow path forming layer 4 has the role of transporting the refrigerant in both the X-axis and Y-axis directions. In the flow path forming layer 4, the refrigerant inflow channel 41 is connected to the fin inlet 31 of the opening forming layer 3 but is not connected to the fin outlet 32, and the refrigerant outflow channel 42 is connected to the fin outlet 32 ​​but is not connected to the fin inlet 31. As a result, the refrigerant inflow channel 41 is interrupted at the location of the fin outlet 32, and the refrigerant outflow channel 42 is interrupted at the location of the fin inlet 31. In the flow path forming layer 5, the refrigerant inflow channel 51 and the refrigerant outflow channel 52 are composed of openings that extend in the X-axis direction.

[0021] The flow path connection layer 6 is a metal layer having a flow path that guides refrigerant flowing in from the inlet / outlet arrangement layer 7 to the refrigerant inlet flow path 51 of the flow path forming layer 5, and refrigerant discharged from the refrigerant outlet flow path 52 of the flow path forming layer 5 to the inlet / outlet arrangement layer 7. The flow path connection layer 6 is in the region outside the region projected from the element arrangement region R100, and has two openings extending in the Y-axis direction at both ends in the X-axis direction. In this example, the flow path connection layer 6 has an inlet connection port 61 extending in the Y-axis direction at the positive X-axis end, and an outlet connection port 62 extending in the Y-axis direction at the negative X-axis end. The inlet connection port 61 is located at a position corresponding to the refrigerant inlet region R53 of the flow path forming layer 5, and the outlet connection port 62 is located at a position corresponding to the refrigerant outlet region R54 of the flow path forming layer 5. The inlet connection port 61 and the outlet connection port 62 penetrate the metal layer in the Z-axis direction. The flow path connection layer 6 is joined to the flow path forming layer 5 at its upper surface.

[0022] The inlet / outlet configuration layer 7 is a metal layer having openings that guide refrigerant flowing in from the outside via piping to the inlet connection port 61 of the flow path connection layer 6, and refrigerant discharged from the outlet connection port 62 of the flow path connection layer 6 to the external piping. The inlet / outlet configuration layer 7 has inlet 71 and outlet 72, which are smaller openings than the inlet connection port 61 and outlet 62 of the flow path connection layer 6, corresponding to the areas where the inlet connection port 61 and outlet 62 of the flow path connection layer 6 are located. The inlet 71 and outlet 72 penetrate the metal layer in the Z-axis direction. A pipe supplying refrigerant is fixed to the inlet 71 via a fixing member. A pipe discharging refrigerant is fixed to the outlet 72 via a fixing member. The inlet / outlet configuration layer 7 is connected to the flow path connection layer 6 at its upper surface.

[0023] Thus, the flow path connection layer 6 is positioned between the flow path forming layer 5 and the inlet / outlet arrangement layer 7. The inlet connection port 61 connects the inlet 71 to the refrigerant inlet flow path 51, and the outlet connection port 62 connects the outlet 72 to the refrigerant outlet flow path 52.

[0024] The refrigerant flowing in from the inlet 71 of the inlet / outlet arrangement layer 7 is spread out at the inlet connection port 61 of the flow path connection layer 6. The refrigerant flows into the refrigerant inlet flow path 51 located in the refrigerant inlet region R53 of the flow path forming layer 5 and flows along the X-axis. The refrigerant flows to the flow path forming layer 4, the opening forming layer 3 and the fin forming layer 2, and after contacting the lower surface of the base layer 1, flows to the fin forming layer 2, the opening forming layer 3 and the flow path forming layer 4. The refrigerant flows along the refrigerant outflow flow path 52 extending in the X-axis direction of the flow path forming layer 5 and flows out from the refrigerant outlet region R54 to the flow path connection layer 6. The refrigerant is collected at the outflow connection port 62 of the flow path connection layer 6 corresponding to the refrigerant outlet region R54, at a position corresponding to the location of the outlet 72 of the inlet / outlet arrangement layer 7, and discharged from the outlet 72 of the inlet / outlet arrangement layer 7. In the flow path forming layer 5, only the refrigerant inlet flow path 51 is located at the inlet connection port 61 connected to the inlet 71, and the refrigerant outflow flow path 52 is not located there. Furthermore, the outlet connection port 62 connected to the outlet 72 is equipped only with a refrigerant outflow channel 52, and no refrigerant inflow channel 51. As a result, the refrigerant flowing into the cooler 10 is not connected to the refrigerant outflow channels 42 and 52, nor is the refrigerant flowing out of the cooler 10 connected to the refrigerant inflow channels 41 and 51.

[0025] Figure 3 is a diagram illustrating an example of refrigerant flow in a cooler according to Embodiment 1. Figure 3 shows a top view from the opening-forming layer 3 to the flow-channel forming layer 5. The refrigerant 90 flows in from the refrigerant inflow channel 51 located in the refrigerant inflow region R53 of the flow-channel forming layer 5 and spreads along the refrigerant inflow channel 51. At this time, the refrigerant 90 also flows into the refrigerant inflow channel 41 of the flow-channel forming layer 4. The refrigerant 90 flowing in the refrigerant inflow channel 51 of the flow-channel forming layer 5 is then guided to the fin inlet 31 of the opening-forming layer 3 via the refrigerant inflow channel 41 of the flow-channel forming layer 4.

[0026] In Figure 3, the projection position 51a of the refrigerant inflow channel 51 in the flow path forming layer 4 is shown, and the projection position 41a of the refrigerant inflow channel 41 in the flow path forming layer 4 is shown in the opening forming layer 3. The flow path forming layer 4 has a cover 43 at the position of the refrigerant inflow channel 41 corresponding to the fin outlet 32 ​​of the opening forming layer 3. The cover 43 blocks the fin outlet 32 ​​of the opening forming layer 3 and has the function of preventing the refrigerant 90 flowing through the refrigerant inflow channel 41 from connecting with the fin outlet 32. As a result, as shown in the projection position 41a of the refrigerant inflow channel 41 in the opening forming layer 3, the refrigerant inflow channel 41 is connected to the fin inlet 31 of the opening forming layer 3, but not to the fin outlet 32. Figure 4 is a diagram showing an example of refrigerant flow in the opening forming layer of a cooler according to Embodiment 1. As shown in Figure 4, the refrigerant 90 from the flow channel forming layer 4 flows along the fin inlet 31, expanding two-dimensionally within the opening forming layer 3 before flowing into the fin forming layer 2.

[0027] The same applies to the discharge of the refrigerant 90. In this case, the flow path forming layer 4 has a cover 44 at the position of the refrigerant outflow flow path 42, which corresponds to the fin inlet 31 of the opening forming layer 3. The cover 44 blocks the fin inlet 31 of the opening forming layer 3 and has the function of preventing the refrigerant 90 flowing through the refrigerant outflow flow path 42 from connecting with the fin inlet 31. As a result, the refrigerant outflow flow path 42 is connected to the fin outlet 32 ​​of the opening forming layer 3, but not to the fin inlet 31.

[0028] In other words, when the fin-forming layer 2 and the flow path forming layer 5 are stacked, the opening of the flow path forming layer 4, i.e., the refrigerant inflow flow path 41, is positioned such that the refrigerant inflow flow path 51 of the flow path forming layer 5 connected to the inlet 71 overlaps at least partially with the fin inlet 31 of the opening forming layer 3 for allowing refrigerant 90 to flow into the fin arrangement region R20, but does not overlap with the fin outlet 32 ​​of the opening forming layer 3 for discharging refrigerant 90 from the fin arrangement region R20. Similarly, the opening of the flow path forming layer 4, i.e., the refrigerant outflow flow path 42, is positioned such that the refrigerant outflow flow path 52 of the flow path forming layer 5 connected to the outlet 72 overlaps at least partially with the fin outlet 32 ​​of the opening forming layer 3 for discharging refrigerant 90 from the fin arrangement region R20, but does not overlap with the fin inlet 31 of the opening forming layer 3 for allowing refrigerant 90 to flow into the fin arrangement region R20. In other words, the refrigerant inflow channel 51 and refrigerant outflow channel 52 of the flow path forming layer 5, the refrigerant inflow channel 41 and refrigerant outflow channel 42 of the flow path forming layer 4, and the fin inlet 31 and fin outlet 32 ​​of the opening forming layer 3 are installed so that the refrigerant 90 that flows in from the inlet 71 of the inlet / outlet arrangement layer 7 does not flow out from the outlet 72 of the inlet / outlet arrangement layer 7 without passing through the fin arrangement region R20.

[0029] Furthermore, while the inlet / outlet arrangement layer 7 has only one inlet 71 and one outlet 72, the fin inlet 31 of the opening-forming layer 3 is provided in multiple locations and extends two-dimensionally across the entire area projected from the fin arrangement region R20, thus requiring the flow channel forming layer 4.

[0030] Next, the detailed configuration of the opening-forming layer 3 will be described. As shown in Figure 2, the intersection of the X and Y axes, i.e., the origin, is located within the region obtained by projecting the element placement region R100, where the element 100, which is the heat source, is placed, onto the opening-forming layer 3. Generally, it is preferable that the origin be at the center of the heat source. Figure 5 is a diagram showing an example of the relationship between the opening-forming layer and the element placement region that constitute the cooler according to Embodiment 1. As shown in Figure 5, the region R100a, obtained by projecting the element placement region R100 onto the opening-forming layer 3, is located inside the region where the fin inlet 31 and fin outlet 32 ​​of the opening-forming layer 3 are located. Furthermore, the region where the fin inlet 31 and fin outlet 32 ​​are located almost coincides with the fin placement region R20. This is because if the element 100 to be cooled, which is bonded to the base layer 1, does not coincide with the fin placement region R20, the element 100 will not be able to be sufficiently cooled.

[0031] Figure 6 is an enlarged top view of a portion of the opening-forming layer. Here, an enlarged view of the first quadrant of the XY plane defined in Figure 2 is shown. In Embodiment 1, the opening-forming layer 3 has a cross-shaped opening 311 which is a fin inlet 31 along the X and Y axes. That is, the cross-shaped opening 311 has a shape that is four rotationally symmetric with respect to the origin and extends planarly in a two-dimensional direction. In other words, the cross-shaped opening 311 does not extend in a one-dimensional direction, but rather has a shape that is four rotationally symmetric with respect to the origin in a two-dimensional plane and is composed of openings that extend in multiple directions.

[0032] The opening-forming layer 3 has openings 312 and 313, which are fin inlets 31, and openings 321 and 322, which are fin outlets 32, located radially away from the origin relative to the cross-shaped opening 311. In other words, multiple openings 311, 312, 313, 321, and 322 are formed in the metal layer. Similar openings are also formed in the second, third, and fourth quadrants. As a result, the shape of the openings in the region projected from the fin arrangement region R20 of the opening-forming layer 3 exhibits four rotational symmetries around the origin.

[0033] The opening 321 adjacent to the cross-shaped opening 311 is positioned at a certain distance from the cross-shaped opening 311 in both the X-axis and Y-axis directions. In other words, it does not extend linearly in one direction, but rather extends planarly in a two-dimensional direction. In this example, the opening 321 has an L-shape where the opening extending in the X-axis direction and the opening extending in the Y-axis direction are connected at a position on a line approximately 45° from the X-axis, and bends vertically at this position. Similarly, the opening 312 adjacent to the opening 321, the opening 322 following the opening 312, and the opening 313 following the opening 322 also extend planarly in a two-dimensional direction and have an L-shape where they bend vertically at a position on a line approximately 45° from the X-axis.

[0034] The cross-shaped opening 311 and the L-shaped openings 312 and 313 serve as fin inlets 31 in the fin arrangement region R20, and are connected to the inlet 71 through openings formed in the layers from the flow channel forming layer 4 to the inlet / outlet arrangement layer 7.

[0035] The L-shaped openings 321 and 322 serve as fin outlets 32 in the fin arrangement region R20, and are connected to outlet 72 through openings formed in the layers from the flow channel forming layer 4 to the inlet / outlet arrangement layer 7.

[0036] Thus, in the cooler 10 according to Embodiment 1, the cross-shaped opening 311 and L-shaped openings 312, 313, which are fin inlets 31 for flowing refrigerant into the fin arrangement region R20, and the L-shaped openings 321, 322, which are fin outlets 32, are alternately arranged in a direction that is radially away from the origin.

[0037] Next, the flow of refrigerant in the structure of the cooler 10 according to Embodiment 1 will be described. Here, with reference to Figure 6, the explanation will focus on the first quadrant of the XY plane. A portion of the refrigerant that flows in from the cross-shaped opening 311 flows out through the groove 22 of the fin arrangement region R20 and out through the L-shaped opening 321 adjacent to the cross-shaped opening 311. Here, the flow of refrigerant can be simplified and divided into the following three elements. (A) The flow of refrigerant that has passed through the cross-shaped opening 311 into the groove 22 of the fin arrangement region R20. Note that in this case, the refrigerant will collide with the base layer 1. (B) Flow of refrigerant passing through groove 22 in fin arrangement region R20. (C) Flow of refrigerant flowing out from groove 22 in fin arrangement region R20 to L-shaped opening 321.

[0038] In each of the three elements described above, the heat dissipation performance, or heat transfer coefficient, of the metal layers constituting the base layer 1 and the fin-forming layer 2 to the refrigerant is different. Furthermore, as the refrigerant flows in through the cross-shaped opening 311, passes through the groove 22 of the fin arrangement region R20, and flows out through the L-shaped opening 321, the temperature of the refrigerant gradually rises.

[0039] Similarly, refrigerant flowing in from the L-shaped opening 312 flows through the groove 22 of the fin arrangement region R20 and flows out from the L-shaped openings 321 and 322 adjacent to the L-shaped opening 312. Refrigerant flowing in from the L-shaped opening 313 flows through the groove 22 of the fin arrangement region R20 and flows out from the L-shaped opening 322 adjacent to the L-shaped opening 313. The flow of refrigerant in these cases is approximately equivalent to the flow described above, where refrigerant flows from the cross-shaped opening 311, through the groove 22 of the fin arrangement region R20, and flows out from the L-shaped opening 321.

[0040] Focusing on the direction of refrigerant flow, the heat dissipation performance transferred from the metal layer to the refrigerant differs for each element of the flow. Furthermore, the temperature of the refrigerant gradually increases. Therefore, a temperature distribution inevitably occurs in the direction of refrigerant flow.

[0041] However, in Embodiment 1, the fin inlet 31 and fin outlet 32 ​​in the opening forming layer 3 for flowing refrigerant into the fin arrangement region R20 are arranged alternately from the center toward the periphery. By narrowing the interval between the alternating arrangements, the generation of temperature distribution can be confined to a narrow area.

[0042] Furthermore, since the fin inlets 31 and fin outlets 32 are arranged alternately, a fin outlet 32 ​​is located next to a fin inlet 31. Similarly, a fin inlet 31 is located next to a fin outlet 32. Consequently, a flow of refrigerant from the adjacent fin inlets 31 is formed at the fin outlet 32, and since the directions of these flows are opposite to each other, the temperature distributions cancel each other out. As a result, the temperature distribution can be averaged in local areas. In particular, since the base layer 1 is made of a metal with good thermal conductivity, the temperature distribution can be reduced.

[0043] Furthermore, since the fin inlets 31 and fin outlets 32 for flowing refrigerant into the fin arrangement region R20 are arranged alternately and in parallel in a direction radially away from the origin, a concentric temperature distribution can be obtained. In addition, by reducing the distance between adjacent fin inlets 31 and fin outlets 32, the distance over which the refrigerant flows through the grooves 22 of the fin arrangement region R20 can be shortened. Therefore, the increase in pressure loss when the refrigerant flows through the grooves 22 of the fin formation layer 2 can be suppressed.

[0044] Furthermore, the fin inlets 31 and fin outlets 32, which are arranged alternately and in parallel in a direction radiating away from a predetermined point in the region obtained by projecting the element arrangement region R100 onto the aperture-forming layer 3, are arranged to exhibit four-fold rotational symmetry with respect to the predetermined point. By making the shape of the opening formed in the aperture-forming layer 3 four-fold rotational symmetry, biases in the X-axis and Y-axis directions are suppressed, and a temperature distribution approaching a concentric circle centered on the predetermined point can be achieved. The case in which the arrangement of the opening has even higher-order rotational symmetry will be discussed later.

[0045] In Embodiment 1, the cross-shaped opening 311 in the opening-forming layer 3 is a fin inlet 31, not a fin outlet 32. Typically, the temperature in the center of a heat source is high, and the temperature around the heat source is low. In Embodiment 1, the origin is located directly below the element 100, which is the heat source. This is because introducing a lower-temperature fluid into the origin improves the cooling capacity.

[0046] Here, the cross-shaped opening 311, which is the fin inlet 31 directly below the heat source element 100, is not only located at or near the origin, but also extends planarly in a two-dimensional direction from the opening near the origin, as shown in Figures 7 and 11, which will be described later. With this structure, the entire element 100 can be cooled uniformly compared to the case where the opening is located only at or near the origin as shown in Figures 7 and 11, which will be described later, and thus the cooling performance can be improved.

[0047] Furthermore, the L-shaped openings 312, 313, which are fin inlets 31, and L-shaped openings 321, 322, which are fin outlets 32, are arranged alternately and in parallel in a direction radiating away from a predetermined point in the region obtained by projecting the element arrangement region R100 onto the opening forming layer 3. By installing them at a certain distance from the cross-shaped opening 311, the temperature distribution can be reduced. Since the L-shaped openings 312, 313, 321, and 322 are installed at a certain distance from the cross-shaped opening 311, they inevitably extend planarly in a two-dimensional direction and have a structure that bends vertically.

[0048] Next, a modified example of the cooler 10 according to Embodiment 1 will be described. Figure 7 is a top view showing another example of the configuration of the opening-forming layer constituting the cooler according to Embodiment 1. In Figure 7 as well, the origin is the center of the region obtained by projecting the element arrangement region R100 onto the opening-forming layer 3. In the example of Figure 7, a point-shaped opening 311a, which will be the fin inlet 31, is provided at the origin. Furthermore, linear openings 312a, 313a, which will be the fin inlets 31, and linear openings 321a, 322a, which will be the fin outlets 32, are arranged alternately and in parallel in a direction radiating away from the origin. In this example, the linear openings 312a, 313a, 321a, 322a have an inclination of 45° or -45° with respect to the X axis and extend in a direction perpendicular to the line passing through the origin. The arrangement of the openings in the opening-forming layer 3 is a rotationally symmetrical arrangement with four rotations around the origin. Therefore, the temperature distribution can be averaged and made closer to concentric circles.

[0049] In the example shown in Figure 7, the structure of the base layer 1 and the fin-forming layer 2 is joined to the opening-forming layer 3. In the opening-forming layer 3, as described above, openings are formed from a single metal layer by processing such as etching and cutting. For this reason, the opening-forming layer 3 has support portions 33 to maintain its structure as a metal layer. In the example shown in Figure 7, square-shaped openings are formed in parallel in the direction away from the origin. The vertices of the square-shaped openings coincide with the X and Y axes, but no openings are formed at these vertices, and these are support portions 33 where the metal layer remains. These support portions 33 support the metal layer sandwiched between the openings, thus maintaining its structure as a metal layer.

[0050] The optimal position and number of support parts 33 are determined by the shape of the fins 21, the thickness (i.e., strength) of the opening-forming layer 3, etc. Figures 8 to 10 are top views showing other examples of the configuration of the opening-forming layer constituting the cooler according to Embodiment 1. Figure 8 shows a case where the support parts 33 are formed on a straight line passing through the origin and inclined at 45° and -45° from the X-axis. Figure 9 is a combination of Figures 7 and 8, showing a case where the support parts 33 are formed on the X-axis and Y-axis, and on a straight line passing through the origin and inclined at 45° and -45° from the X-axis. Note that if the support parts 33 are thin, the position of the support parts 33 does not significantly affect the temperature distribution even if it is not in a position with four rotational symmetries around the origin. In other words, if the support parts 33 are formed thinly, the support parts 33 can be provided at any position. However, ideally, as shown in Figure 10, it is preferable to have no support parts 33. In this case, the metal layer constituting the opening-forming layer 3 is bonded to the base layer 1 and fin-forming layer 2 structures, and then only the metal layer is processed, which complicates the manufacturing process.

[0051] As described above, generally, the temperature at the center of a heat source is high, and the temperature at the periphery of the heat source is low because it does not generate heat. For this reason, in Figures 7 to 10, the spacing between adjacent openings in the direction radiating away from the origin is wider on the outside than on the inside. In other words, the spacing between adjacent fin inlets 31 and fin outlets 32 is wider at positions farther from a point in the region projected onto the element arrangement region R100 than at positions closer to that point in the region. In one example, the spacing between adjacent openings can be made wider the further away from a defined point.

[0052] By widening the spacing between adjacent openings on the outside compared to the inside, the length of the flow path for the refrigerant increases in the outer fin arrangement region R20, which is the periphery of the heat source. As a result, the flow rate decreases due to increased pressure loss on the outside, and the length from one fin inlet 31 to the fin outlet 32 ​​increases, thus increasing the total heat generation in the region of the flow path through which the refrigerant flows on the outside. Consequently, the temperature rise of the fluid on the outside is greater than the temperature rise of the fluid on the inside, the temperature around the heat source rises, and the temperature distribution of the heat source can be reduced. However, since the temperature of the center also rises when the temperature around the heat source rises, it is necessary to design the spacing between openings according to the heat generation amount, required temperature specifications, and temperature distribution.

[0053] Figure 11 is a top view showing another example of the configuration of the opening-forming layer constituting the cooler according to Embodiment 1. In Figure 11 as well, the origin is the center of the region projected from the element arrangement region R100. In the example of Figure 11, arc-shaped openings 311b, 312b, 313b, which serve as fin inlets 31, and arc-shaped openings 321b, 322b, which serve as fin outlets 32, are arranged alternately and in parallel in a direction radiating away from the origin. In the example of Figure 11 as well, the arrangement of the openings in the region projected from the element arrangement region R100 is a rotationally symmetrical arrangement with four rotations around the origin. In addition, the spacing between adjacent openings is wider on the outer side than on the inner side.

[0054] In the case of Figure 11, the fin inlet 31 and fin outlet 32 ​​are formed into a circular shape by connecting the arc-shaped openings 311b, 312b, 313b, 321b, and 322b with the support portion 33. Thus, the shapes of the fin inlet 31 and fin outlet 32 ​​are not only circularly symmetric but also possess higher-order rotational symmetry, which further improves the uniformity of the temperature distribution. However, generally, the grooves 22 in the fin arrangement region R20 are often formed by a combination of straight lines. Therefore, as described above, it is preferable for the openings 311b, 312b, 313b, 321b, and 322b in the opening-forming layer 3 to coincide with the direction of the openings in the fin arrangement region R20 in terms of suppressing the increase in pressure loss. In other words, it is desirable that the fins 21 in the fin arrangement region R20 of the fin-forming layer 2 also be arranged so that the grooves 22 are arc-shaped, i.e., circularly symmetric, in line with the openings in the opening-forming layer 3. However, the manufacturing of circularly symmetric fins 21 and openings is more complex compared to linear shapes.

[0055] In addition, if the opening-forming layer 3 has a shape as shown in Figures 7 to 11, the shape of the flow channels of the flow channel-forming layer 4 and flow channel-forming layer 5 in Figure 2 may change. In this case, the flow channels of the flow channel-forming layer 4 and flow channel-forming layer 5 are arranged so that the refrigerant flowing in from the inlet 71 of the inlet / outlet arrangement layer 7 does not flow out from the outlet 72 of the inlet / outlet arrangement layer 7 without passing through the fins 21. In other words, the opening of the flow channel-forming layer 4, i.e., the refrigerant inflow flow channel 41, is installed so that the refrigerant inflow flow channel 51 of the flow channel-forming layer 5 connected to the inlet 71 overlaps at least a portion with the fin inlet 31 of the opening-forming layer 3 for flowing refrigerant into the fin arrangement region R20, but does not overlap with the fin outlet 32 ​​of the opening-forming layer 3 for discharging refrigerant from the fin arrangement region R20. Furthermore, the opening of the flow channel forming layer 4, i.e., the refrigerant outflow channel 42, is positioned such that the refrigerant outflow channel 52 of the flow channel forming layer 5, which is connected to the outlet 72, overlaps at least partially with the fin outlet 32 ​​of the opening forming layer 3 for discharging refrigerant from the fin arrangement region R20, but does not overlap with the fin inlet 31 of the opening forming layer 3 for allowing refrigerant to flow into the fin arrangement region R20. In other words, the refrigerant inflow channel 51 and refrigerant outflow channel 52 of the flow channel forming layer 5, the refrigerant inflow channel 41 and refrigerant outflow channel 42 of the flow channel forming layer 4, and the fin inlet 31 and fin outlet 32 ​​of the opening forming layer 3 are positioned so that refrigerant flowing in from the inlet 71 of the inlet / outlet arrangement layer 7 does not flow out from the outlet 72 of the inlet / outlet arrangement layer 7 without passing through the fin arrangement region R20.

[0056] Furthermore, in the example described above, since the cooler 10 has one inlet 71 and one outlet 72, the refrigerant from the inlet 71 is spread out in the flow path connecting layer 6 and connected to the refrigerant inlet region R53 of the flow path forming layer 5, and the refrigerant from the refrigerant outlet region R54 of the flow path forming layer 5 is collected in the flow path connecting layer 6 and connected to the outlet 72 of the inlet / outlet arrangement layer 7. When the cooler 10 has multiple inlets 71 and multiple outlets 72, the flow path forming layer 4 and the flow path forming layer 5 may have different shapes in order to connect the multiple inlets 71 to the refrigerant inlet region R53 of the flow path forming layer 5 and the multiple outlets 72 to the refrigerant outlet region R54 of the flow path forming layer 5.

[0057] Furthermore, while Figures 5 and 6 show the case where the spacing between adjacent L-shaped openings 312, 313, 321, and 322 is constant, as shown in Figures 7 to 11, the spacing between adjacent L-shaped openings 312, 313, 321, and 322 may be wider on the outside than on the inside.

[0058] Figure 12 is a schematic top view showing the positional relationship between the openings in the opening-forming layer and the grooves in the fin arrangement area of ​​the fin-forming layer. Figure 12 is an enlarged view of a part of region R34 in Figure 7. The fin inlets 31 and fin outlets 32, which are openings in the opening-forming layer 3, are positioned in a direction that coincides with the direction of the openings, which are grooves 22 between the fins 21 installed in the fin-forming layer 2. In other words, the fin inlets 31 and fin outlets 32 are positioned in the direction in which the openings formed by the fins 21 on the surface in contact with the opening-forming layer 3 extend in the XY plane. As a result, when refrigerant flows from the fin inlets 31 formed in the opening-forming layer 3 into the grooves 22 of the fin-forming layer 2, and conversely when refrigerant flows out from the grooves 22 of the fin-forming layer 2 into the fin outlets 32 formed in the opening-forming layer 3, there are fewer obstacles obstructing the flow, and the increase in pressure loss can be suppressed.

[0059] The adjacent fin inlets 31 and fin outlets 32 of the opening-forming layer 3 are arranged radially away from the origin, resulting in different areas. In other words, the area of ​​the opening decreases as it moves further away from the origin. Consequently, if the grooves 22 of the fin-forming layer 2 are one-dimensional, stagnation occurs, leading to an increase in temperature distribution and a decrease in cooling capacity. For this reason, it is desirable that the grooves 22 of the fin-forming layer 2 be structured to expand locally two-dimensionally between the fin inlets 31 and fin outlets 32. This suppresses uneven flow between the fin inlets 31 and fin outlets 32, eliminates stagnation, and improves cooling performance.

[0060] Figure 13 is a partially enlarged top view showing an example of the configuration of the fin-forming layer constituting the cooler according to Embodiment 1. Figure 13 is an enlarged view of a part of the fin arrangement region R20 in the fin-forming layer 2. In Figure 13, the flow of refrigerant in the groove 22 of the fin arrangement region R20 of the fin-forming layer 2 shown in Figure 2 is indicated by arrows. As shown in Figure 13, the groove 22 of the fin arrangement region R20 has local periodicity, and the flow repeatedly merges and branches in a narrow area. Furthermore, this periodic groove 22 is formed throughout the entire fin arrangement region R20. In one example, as shown in Figure 13, the refrigerant flowing through the groove 22, which is the flow path of the fin arrangement region R20, merges at position 23 and then branches. Alternatively, it is desirable that the openings for forming the fins 21 be provided such that the refrigerant repeatedly merges and branches between adjacent fin inlets 31 and fin outlets 32. Therefore, even if the areas of the fin inlet 31 and the fin outlet 32 ​​are different, the flow can be made uniform in two dimensions, that is, in all directions within the plane formed by the X and Y axes. As a result, the temperature distribution can be reduced and the cooling capacity can be improved.

[0061] Figure 14 is a top view showing another example of the configuration of the fin-forming layer constituting the cooler according to Embodiment 1. Figure 15 is an enlarged top view of a part of the fin arrangement region of the fin-forming layer in Figure 14. Figure 15 is an enlarged view of the region R210 in Figure 14. Figures 14 and 15 show an example of a fin-forming layer 2 having fins 21 of a different shape from those in Figure 13, which locally merge and diverge repeatedly. In the example of Figures 14 and 15, the fin-forming layer 2a has a thin plate 210 in which an opening 211 extending in a first direction is formed in the fin arrangement region R20, which includes the region onto which the element arrangement region R100 is projected, and a thin plate 220 in which an opening 221 extending in a second direction intersecting the first direction is formed in the fin arrangement region R20, and has a structure in which multiple thin plates 210 and 220 are stacked alternately. In the fin arrangement region R20 of the fin-forming layer 2a, the fins 21a are formed by the overlapping of an opening 211 extending in the first direction and an opening 221 extending in the second direction. In the examples of Figures 14 and 15, a groove 22a is formed by the stacking of the openings 211 and 221. The groove 22a has a three-dimensional mesh-like structure.

[0062] Figure 16 is a top view showing an example of the configuration of the opening-forming layer corresponding to the fin-forming layer in Figure 14. In the example shown in Figure 16, the cross-shaped opening 311c passing through the origin is positioned in a direction that coincides with the direction of the groove 22a in the fin-positioning region R20 in Figures 14 and 15, i.e., the first and second directions. In this case as well, the L-shaped openings 312c, 313c, 321c, and 322c are positioned in parallel in a direction radiating away from the origin, and at a certain distance from the cross-shaped opening 311c.

[0063] The refrigerant flows from the fin inlet 31 of the opening-forming layer 3 into the fin arrangement region R20 of the fin-forming layer 2. Specifically, it flows in through an opening formed in the fin arrangement region R20 that overlaps with the fin inlet 31. The opening formed in the fin arrangement region R20 corresponds to the position of the groove 22a as viewed from the lower surface of the fin-forming layer 2a. The refrigerant then flows through gaps formed along the openings 211 and 221 of the laminated thin plates 210 and 220, repeatedly merging and branching, before flowing out through the opening that overlaps with the fin outlet 32 ​​and the fin outlet 32 ​​of the opening-forming layer 3. By making the thin plates 210 and 220 that constitute the fins 21a thin, a narrow flow path can be created, thus enabling the realization of a cooler with high cooling performance.

[0064] In the fin 21a shown in Figure 14, the flow repeatedly merges and branches within a narrow region. In other words, the fin 21a shown in Figure 14 has a flow channel that can spread the flow uniformly in all directions within the plane formed by the X and Y axes in two dimensions. There are no particular restrictions on the manufacturing method or form of the fin 21a itself.

[0065] As described above, the cooler 10 according to Embodiment 1 comprises a base layer 1 to which the element 100 is bonded, a fin forming layer 2 having a fin arrangement region R20 on which a plurality of fins 21, 21a are arranged and connected to the base layer 1, and an opening forming layer 3 connected to the fin forming layer 2 and having a plurality of fin inlets 31 and a plurality of fin outlets 32 for flowing refrigerant into the fin arrangement region R20. The plurality of fin inlets 31 are connected to an inlet 71 through which the refrigerant of the cooler 10 flows in via an inflow channel, and the fin outlets 32 are connected to an outlet 72 through which the refrigerant of the cooler 10 flows out via an outflow channel. Furthermore, the plurality of fin inlets 31 and the plurality of fin outlets 32 are arranged alternately and in parallel in a direction radially away from a point in the region on which the shape of the element 100 is projected onto the opening forming layer 3. This makes the temperature distribution due to the heat generated by the element 100 closer to concentric circles and reduces the temperature distribution. In addition, it is possible to suppress the increase in refrigerant pressure loss in the fin forming layer 2 between the fin inlets 31 and the fin outlets 32.

[0066] Embodiment 2. Figure 17 is a schematic cross-sectional view showing an example of the configuration of a cooler according to Embodiment 2. Note that the same reference numerals are used for components identical to those described in Embodiment 1, and their descriptions are omitted. The cooler 10a of Embodiment 2 further includes a flow path forming layer 8 between the opening forming layer 3 and the flow path forming layer 4.

[0067] Figure 18 is a top view showing an example of the configuration of a channel-forming layer constituting a cooler according to Embodiment 2. The channel-forming layer 8 is a metal layer having channels 81 and 82, which are openings, in a region that encompasses the region onto which the element arrangement region R100 is projected. The region in which the channels 81 and 82 of the channel-forming layer 8 are arranged is called the channel arrangement region R80. The channel-forming layer 8 corresponds to the first channel-forming layer.

[0068] Figure 19 shows an example of a state in which the opening-forming layer and the channel-forming layer are superimposed. In Figure 19, the parts of the channels 81 and 82 of the channel-forming layer 8 that overlap with the area of ​​the opening-forming layer 3 other than the opening are shaded. In the example shown in Figure 19, the channel arrangement region R80 encompasses the element arrangement region R100 and has a larger area than the element arrangement region R100. In this example, the size of the channel arrangement region R80 in the Y-axis direction is the same as that of the element arrangement region R100, but the size in the X-axis direction is larger than that of the element arrangement region R100. Also, as shown in Figures 18 and 19, the channels 81 and 82 of the channel arrangement region R80 are arranged corresponding to the opening of the opening-forming layer 3. The widthwise centers of the channels 81 and 82 of the channel-forming layer 8 and the widthwise centers of the corresponding openings of the opening-forming layer 3 are arranged to coincide. Thus, the channel arrangement region R80 has a cross-shaped opening 81a passing through the origin and L-shaped openings 81b and 82b. The L-shaped openings 81b and 82b are arranged in parallel in a direction radiating away from the origin. In other words, the channel forming layer 8 has a channel arrangement region R80 that encompasses a region having openings 81a and 81b, which are projections of the fin inlets 31 that are alternately and parallel arranged in a direction radiating away from the origin of the opening forming layer 3, and an opening 82b, which is projection of the fin outlet 32. Therefore, the width and length of the channels 81 and 82 of the channel forming layer 8 are equal to or greater than the width and length of the openings of the opening forming layer 3.

[0069] In order to widen the area through which the refrigerant flows in the fin arrangement region R20 of the fin forming layer 2, the opening of the opening forming layer 3 is often made narrow. Also, in Figure 2 of Embodiment 1, the refrigerant inflow channel 41 and refrigerant outflow channel 42, which are the openings of the flow path forming layer 4, basically encompass the area projected onto the flow path forming layer 4 from the fin inlet 31 and fin outlet 32, which are the openings of the opening forming layer 3, and the refrigerant inflow channel 51 and refrigerant outflow channel 52, which are the openings of the flow path forming layer 5. However, in order to prevent the refrigerant flowing in from the inlet 71 from flowing out from the outlet 72 without passing through the fins 21, an area without an opening in the flow path forming layer 4 occurs directly above the opening in the opening forming layer 3. In this area, the refrigerant does not easily flow to the fins 21. Conversely, an area without an opening in the opening forming layer 3 also occurs at a position corresponding to the opening in the flow path forming layer 4. As a result, the flow becomes uneven, the temperature distribution increases, and a decrease in cooling capacity may occur.

[0070] Therefore, in Embodiment 2, as shown in Figure 18, a channel forming layer 8 having a channel arrangement region R80 in which channel paths 81 and 82 are formed, which are projected onto fin inlets 31 and fin outlets 32 that are alternately and parallelly arranged in a direction radially away from the origin of the opening forming layer 3, is connected to the opening forming layer 3. A wide channel is installed above the area of ​​the channel forming layer 4 that does not have an opening, allowing the refrigerant to circulate and flow evenly across the fins 21. As a result, the temperature distribution can be reduced and the cooling capacity can be improved. In addition, a wide channel is installed below the area of ​​the opening forming layer 3 that does not have an opening, at a position corresponding to the opening of the channel forming layer 4, allowing the refrigerant to circulate and flow evenly across the fins 21.

[0071] Furthermore, the channels 81 and 82 arranged in the channel forming layer 8 smooth out the flow bias that occurs at the openings in the channel forming layer 4. Therefore, by reducing the thickness of the opening forming layer 3 and increasing the thickness of the channel forming layer 8, specifically by making the thickness of the channel forming layer 8 greater than the thickness of the opening forming layer 3, the elimination of refrigerant flow bias can be further improved. As a result, the temperature distribution can be further reduced, and the cooling capacity can be improved.

[0072] The cooler 10a according to Embodiment 2 is connected to the opening forming layer 3 and includes a projected region which is the area where the plurality of fin inlets 31 and plurality of fin outlets 32 of the opening forming layer 3 are projected. The cooler further includes a flow channel forming layer 8 which has flow channels 81 and 82 in a region larger than the projected region, and in which at least one of the length and width of the plurality of fin inlets 31 and plurality of fin outlets 32 of the opening forming layer 3 is increased. As a result, wide flow channels 81 and 82 are installed above the region of the flow channel forming layer 4 where there are no openings, and the coolant flows evenly across the fins 21 as it circulates. This has the effect of reducing the temperature distribution and improving the cooling capacity.

[0073] Embodiment 3. Figure 20 is a schematic cross-sectional view showing an example of the configuration of a cooler according to Embodiment 3. Note that the same reference numerals are used for components identical to those described in Embodiment 1, and their descriptions are omitted. Figure 20 shows a case where three elements 100, arranged in the same direction, for example in the X-axis direction, are joined to a single cooler 10b. Even in this case, focusing on region A of the cooler 10b to which one element 100 is joined, the structure from the base layer 1 to the flow path forming layer 5 is substantially the same as that shown in Figure 2. The same applies to elements 100 joined at other positions. That is, the cooler 10b has a configuration in which the structures of each metal layer shown in Figure 2 are arranged in parallel three times.

[0074] The cooler 10b according to Embodiment 3 differs from Embodiment 1 in the configuration of the flow path connecting layer 6b and the inlet / outlet arrangement layer 7b, and further includes a flow path distribution layer 9 between the flow path connecting layer 6b and the inlet / outlet arrangement layer 7b. In other words, the flow path connecting layer 6b, the flow path distribution layer 9, and the inlet / outlet arrangement layer 7b are joined in order below the flow path forming layer 5.

[0075] Figure 21 is a top view showing an example of the configuration of the flow path connection layer constituting the cooler according to Embodiment 3. As shown in Figure 21, the flow path connection layer 6b has inlet connection ports 61b and outlet connection ports 62b at positions corresponding to each of the three elements 100. However, in Embodiment 1, as shown in Figure 2, the positions of the inlet connection port 61 and outlet connection port 62 in the Y-axis direction were the same, but in Embodiment 3, the positions of the inlet connection port 61b and outlet connection port 62b in the Y-axis direction are offset. In the example in Figure 21, the inlet connection port 61b is offset from the outlet connection port 62b by a distance Δy defined in the positive Y-axis direction.

[0076] The flow path distribution layer 9 is a metal layer having a flow path that distributes the refrigerant flowing in from the inlet 71b of the inlet / outlet arrangement layer 7b to the respective inlet connection ports 61b of the flow path connection layer 6b, and merges the refrigerant from the respective outlet connection ports 62b of the flow path connection layer 6b to the outlet 72b of the inlet / outlet arrangement layer 7b. Figure 22 is a top view showing an example of the configuration of the flow path distribution layer constituting the cooler according to Embodiment 3. As shown in Figure 22, the flow path distribution layer 9 has a distribution flow path 91 that distributes the refrigerant from the inlet 71b to the inlet connection ports 61b of the flow path connection layer 6b, and a merging flow path 92 that merges the refrigerant from the outlet connection ports 62b of the flow path connection layer 6b to the outlet 72b. The distribution flow path 91 is arranged to intersect with the inlet connection ports 61b of the flow path connection layer 6b, but not with the outlet connection ports 62b. The merging flow path 92 is arranged to intersect with the outlet connection ports 62b of the flow path connection layer 6b, but not with the inlet connection ports 61b. In this example, the distribution channel 91 is positioned on the positive side in the Y-axis direction relative to the merging channel 92.

[0077] Figure 23 is a top view showing an example of the configuration of the inlet / outlet arrangement layer constituting the cooler according to Embodiment 3. As shown in Figure 23, the inlet / outlet arrangement layer 7b has one inlet 71b and one outlet 72b. The inlet 71b is positioned at a location that intersects with the distribution channel 91 of the flow path distribution layer 9. The outlet 72b is positioned at a location that intersects with the merging channel 92 of the flow path distribution layer 9. In the example of Figure 23, the inlet 71b and outlet 72b are shown to be spaced apart in the Y-axis direction at a location corresponding to the element 100 at the left end of Figure 20, but the inlet 71b and outlet 72b can be provided at any location as long as the inlet 71b intersects with the distribution channel 91 of the flow path distribution layer 9 and the outlet 72b intersects with the merging channel 92 of the flow path distribution layer 9. Furthermore, in Embodiment 3, although three elements 100 are arranged in the cooler 10b, there is only one inlet 71b and one outlet 72b.

[0078] As described above, a flow path distribution layer 9 is inserted between the flow path connection layer 6b and the inlet / outlet arrangement layer 7b. The distribution flow path 91 connects one inlet 71b to the inlet connection port 61b of the flow path connection layer 6b, which is provided corresponding to each of the three elements 100, and the confluence flow path 92 connects one outlet 72b to the outlet connection port 62b of the flow path connection layer 6b, which is provided corresponding to each of the three elements 100. As a result, the refrigerant flowing in from the inlet 71b of the inlet / outlet arrangement layer 7b flows through the distribution flow path 91 to the inlet connection port 61b connected to the fins 21 that cool each element 100. At the location of each element 100, the refrigerant reaches the fins 21 and returns to the outlet connection port 62b. The refrigerant flowing out from the outlet connection port 62b flows through the confluence flow path 92 and is discharged from the outlet 72b of the inlet / outlet arrangement layer 7b. In this example, the X-axis corresponds to the third direction, and the Y-axis corresponds to the fourth direction.

[0079] Thus, even if multiple heat source elements 100 are present on the cooler 10b, which is a heat sink, cooling can be performed in the same configuration as when a single element 100 is present on the cooler 10b.

[0080] In Figure 21, the region R20b, which is the projection of the fin arrangement region R20 of the fin formation layer 2 onto the flow channel connection layer 6b, is shown by a dashed line. Hereafter, the region R20b onto which the fin arrangement region R20 is projected will be referred to as the fin projection region R20b. As shown in Figure 21, the three fin projection regions R20b are arranged in parallel along the X-axis direction. However, the fin inlet 31 and fin outlet 32, which are openings to the fin arrangement region R20 having fins 21 that form grooves 22 that repeatedly merge and branch locally, are defined by the opening formation layer 3. Figure 24 is a top view showing an example of the configuration of the flow channel connection layer constituting the cooler according to Embodiment 3. As shown in Figure 24, the fin arrangement regions R20 provided on each of the three elements 100 are connected to form one fin arrangement region. The dashed fin projection region R20c is the projection of this fin arrangement region onto the flow channel connection layer 6b. In this way, fins 21 may be installed over the entire surface of the fin formation layer 2.

[0081] Although the above example describes the case where three elements 100 are installed in one cooler 10b, the cooler 10b of Embodiment 3 can also be applied to two elements 100, or four or more elements 100.

[0082] The cooler 10b according to Embodiment 3 has a plurality of elements 100 arranged in one direction, and each element 100 has the same structure from the base layer 1 to the flow path forming layer 5 as described in Embodiment 1, and below the flow path forming layer 5, there is a flow path connection layer 6b, a flow path distribution layer 9, and an inlet / outlet arrangement layer 7b. In the flow path connection layer 6b, the position of the inlet connection port 61b is offset along the extending direction relative to the position of the outlet connection port 62b. The flow path distribution layer 9 has a distribution flow path 91 connecting a plurality of inlet connection ports 61b of the flow path connection layer 6b and a confluence flow path 92 connecting a plurality of outlet connection ports 62b. The inlet / outlet arrangement layer 7b has an inlet 71b provided at a part of the position corresponding to the distribution flow path 91 and an outlet 72b provided at a part of the position corresponding to the confluence flow path 92. With this configuration, even when a plurality of elements 100 are connected to the cooler 10b, the temperature distribution due to the heat generated by the elements 100 can be made closer to concentric circles, and the temperature distribution can be reduced. Furthermore, it is possible to suppress the increase in refrigerant pressure loss in the fin-forming layer 2 between the fin inlet 31 and the fin outlet 32.

[0083] The configurations shown in the above embodiments are merely examples, and it is possible to combine them with other known technologies, combine different embodiments, and omit or modify parts of the configuration without departing from the gist of the invention. [Explanation of Symbols]

[0084] 1 Base layer, 2,2a Fin-forming layer, 3 Opening-forming layer, 4,5,8 Flow channel forming layer, 6,6b Flow channel connection layer, 7,7b Inlet / outlet arrangement layer, 9 Flow channel distribution layer, 10,10a,10b Cooler, 21,21a Fins, 22,22a Grooves, 31 Fin inlet, 32 Fin outlet, 33 Support section, 41,51 Refrigerant inlet flow channel, 42,52 Refrigerant outlet flow channel, 43,44 Cover, 61,61b Inlet connection port, 62,62b Outlet connection port, 71,71b Inlet, 72,72b Outlet, 81,82 Flow channels, 81a, 81b, 82b, 211, 221, 311, 311a, 311b, 311c, 312, 312a, 312b, 312c, 313, 313a, 313b, 313c, 321, 321a, 321b, 321c, 322, 322a, 322b, 322c Opening, 90 Refrigerant, 91 Distribution flow channel, 92 Confluence flow channel, 100 Element, 101 Thermal conduction layer, 210, 220 Thin plate, A, R34, R100a, R210 Region, R20 Fin arrangement region, R20b, R20c Fin projection region, R53 Refrigerant inflow region, R54 Refrigerant outflow region, R80 Flow channel arrangement region, R100 Element arrangement region, R101 Region where the heat conduction layer is located.

Claims

1. A cooler that is joined to an element and cools the element, The base layer to which the aforementioned element is bonded, A fin-forming layer having a fin arrangement region where a plurality of fins connected to the base layer are arranged, An opening-forming layer connected to the fin-forming layer, having a plurality of fin inlets and a plurality of fin outlets for flowing refrigerant into the fin arrangement region, Equipped with, The multiple fin inlets are connected to the inlets through which the refrigerant of the cooler flows in via inflow paths. The multiple fin outlets are connected to the outlets from which the refrigerant of the cooler flows out via outlet channels. A cooler characterized in that the plurality of fin inlets and plurality of fin outlets are arranged alternately and in parallel in a direction radially away from a point in the region in which the shape of the element is projected onto the opening forming layer.

2. The cooler according to claim 1, characterized in that the distance between adjacent fin inlets and fin outlets is wider at positions further from the point in the region than at positions closer to the point.

3. The cooler according to claim 1 or 2, characterized in that the arrangement of the plurality of fin inlets and plurality of fin outlets is rotationally symmetric four times with respect to the point.

4. The cooler according to claim 1 or 2, characterized in that the fins are provided such that the refrigerant repeatedly merges and branches between adjacent fin inlets and fin outlets.

5. The cooler according to claim 1 or 2, characterized in that the plurality of fin inlets and plurality of fin outlets are arranged in accordance with the direction of the openings formed by the fins on the surface in contact with the opening-forming layer.

6. The cooler according to claim 1 or 2, characterized in that the plurality of fin inlets and plurality of fin outlets are formed by connecting the respective ends of a plurality of openings extending in different directions.

7. The cooler according to claim 6, characterized in that the plurality of fin inlets and plurality of fin outlets have a shape in which a linear opening extending in a first direction and a linear opening extending in a second direction perpendicular to the first direction are connected.

8. The cooler according to claim 1 or 2, further comprising a first channel forming layer connected to the opening forming layer, which includes a projection region that is a region onto which the plurality of fin inlets and plurality of fin outlets of the opening forming layer are projected, and having openings in a region larger than the projection region, where at least one of the length and width of the plurality of fin inlets and plurality of fin outlets of the opening forming layer is increased.

9. The cooler according to claim 8, characterized in that the thickness of the first channel forming layer is greater than the thickness of the opening forming layer.

10. A second channel forming layer connected to the opening forming layer and having the inflow channel and the outflow channel, An inlet and outlet arrangement layer having the inlet and outlet, A flow channel connecting layer is disposed between the second flow channel forming layer and the inlet / outlet arrangement layer, and has an inlet connection port connecting the inlet and the inlet flow channel, and an outlet connection port connecting the outlet and the outlet flow channel, Furthermore, The base layer has a plurality of elements arranged in a third direction. The cooler according to claim 1 or 2, characterized in that each of the multiple elements is provided with a plurality of fin inlets, a plurality of fin outlets, an inflow channel, and an outflow channel.

11. The inlet / outlet arrangement layer and the flow path connection layer further comprises a flow path distribution layer having a distribution flow path for distributing the refrigerant flowing in from the inlet to each of the inlet connection ports, and a merging flow path for merging the refrigerant from the outlet connection port to the outlet, The inlet and outlet connections of the flow path connection layer are positioned with a staggered position in a fourth direction perpendicular to the third direction. The distribution channel is an opening extending in the third direction, which is arranged to connect to the inlet connection port at a position that does not overlap with the outlet connection port in the fourth direction. The cooler according to claim 10, characterized in that the confluence channel is an opening extending in the third direction, which is arranged to connect with the outlet connection port at a position that does not overlap with the inlet connection port in the fourth direction.

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