WO2016031227A1 - Heat receiver, cooling device using same, and electronic device using same - Google Patents

Abstract

A heat receiver is provided with: a heat-receiving plate (17) that comprises a heat-receiving surface on one surface side thereof and a vaporizing section on the opposite surface side from the heat-receiving surface; and a heat-receiving cover (18) that is arranged on the vaporizing section side of the heat-receiving plate (17). In addition, a heat-receiving space is formed by the heat-receiving plate (17) and the heat-receiving cover (18). The heat receiver is additionally provided with a refrigerant inlet (21) on the upper surface of the heat-receiving space and a refrigerant outlet (22) on the lower surface of the heat-receiving space. A refrigerant is supplied into the heat-receiving space by the refrigerant inlet (21) via a check valve (12), the refrigerant flows out from the refrigerant outlet (22), and a plurality of recesses or protrusions are provided in the vertical direction on the vaporizing section side of the heat-receiving plate (17). The heat-receiving cover (18) comprises a protruding section (20) that protrudes on the heat-receiving plate (17) side at a part corresponding to the vaporizing section. In addition, the heat-receiving space is divided into a refrigerant inlet (21) side and a refrigerant outlet (22) side by arranging the protruding section (20) to be in contact with the heat-receiving plate (17) or with a gap therebetween so that the refrigerant is retained on the refrigerant inlet side of the heat-receiving space.

Description

Heat receiver, cooling device using the same, and electronic device using the same

The present invention relates to a heat receiver, a cooling device using the heat receiver, and an electronic device using the cooling device using the heat receiver.

For example, in a server, as the processing capacity is improved (high-speed processing), a semiconductor element such as a CPU (Central Processing Unit) is accompanied by extremely large heat generation. As a result, a cooling device for cooling the semiconductor element is indispensable for ensuring the operational stability of the entire system.

Conventional cooling devices have been configured as follows.

That is, it includes a heat receiving part, a heat radiating part connected to the outlet of the heat receiving part via a heat radiating path, and a return path connecting the heat radiating part and the inlet of the heat receiving part. The heat receiving unit includes a heat receiving plate that contacts the heat generating element to absorb heat and a heat receiving cover that covers the surface of the heat receiving plate and forms a heat receiving space for evaporating the refrigerant that has flowed into the surface. The return path is provided with a check valve that opens due to a balance between the water head pressure of the refrigerant condensed and retained at the inlet and the pressure in the heat receiving space. An inflow pipe for retaining the condensed refrigerant upstream of the check valve is provided on the upstream side of the inflow port. In the heat receiving space, the heat receiving plate includes a refrigerant inflow portion at the center and a vaporization portion provided with a radial groove toward the outer periphery of the refrigerant inflow portion. An introduction pipe is provided that extends from the inflow port toward the refrigerant inflow portion and into which the condensed refrigerant flows. The heat receiving plate of the heat receiving unit is arranged in a substantially vertical direction. The introduction pipe was disposed in a substantially vertical direction with respect to the heat receiving plate (see, for example, Patent Document 1).

JP 2009-88127 A

The problem with the conventional cooling device is that the cooling performance is lowered when the heat receiving portion of the cooling device is arranged substantially vertically and the size of the heat receiving portion is increased.

That is, in the conventional cooling device, a part of the refrigerant flowing into the refrigerant inflow part from the introduction pipe comes into contact with the refrigerant inflow part and receives heat from the heat receiving plate to evaporate. Due to the rapid volume expansion at this time, it diffuses as a high-speed mixed phase (gas phase and liquid phase) flow on the vaporization section together with the non-boiling liquid phase refrigerant. After the initial boiling, the non-boiling liquid phase refrigerant spreads in the form of a thin film on the surface of the vaporization section. And by the continuous heating from a heat generating body, the unboiled liquid phase refrigerant | coolant is heated and vaporized in an instant. Thus, the heat receiving plate is continuously deprived of vaporization heat and cooled.

However, the condensed refrigerant is supplied from the introduction pipe arranged in the substantially horizontal direction in the heat receiving part arranged in the substantially vertical direction. For this reason, the mixed-phase refrigerant generated near the leading end of the introduction pipe and diffused by the initial boiling easily flows downward due to gravity instead of evenly diffusing to the periphery. Therefore, it may be difficult to supply a sufficient mixed phase refrigerant to the upper side of the introduction pipe. As a result, there was a problem that the heat of the upper part of the heat receiving plate could not be sufficiently removed and the cooling performance was lowered. Further, Patent Document 1 describes a method for suppressing this influence when the area of the heat receiving plate arranged vertically is a relatively small size of several hundred mm ² or less. However, in the case where the area of the heat receiving plate exceeds several hundred mm ² , particularly 1000 mm ² or more, sufficient refrigerant cannot often be supplied to the entire surface of the heat receiving plate in a substantially vertical arrangement. In such a configuration, it is a serious problem that not only the performance of the cooling device is lowered, but also it is difficult to ensure the operational stability of the cooling device.

The present invention aims to improve the cooling performance and ensure the operational stability of a cooling device using a large area heat receiving plate arranged in a substantially vertical direction.

In order to achieve this object, a heat receiver of the present invention includes a heat receiving plate having a heat receiving surface on one side and a vaporizing portion on the other side of the heat receiving surface, and a heat receiving cover disposed on the vaporizing portion side of the heat receiving plate, Is provided. Further, a heat receiving space is formed by the heat receiving plate and the heat receiving cover. A refrigerant inlet is provided on the upper surface of the heat receiving space, and a refrigerant outlet is provided on the lower surface of the heat receiving space. In addition, the refrigerant is supplied into the heat receiving space through the check valve at the refrigerant inlet, the refrigerant flows out from the refrigerant outlet, and a plurality of concave or convex portions are provided in the vertical direction on the vaporization portion side of the heat receiving plate. Provide. Further, the heat receiving cover has a protruding portion that protrudes toward the heat receiving plate at a portion corresponding to the vaporizing portion. Further, the protruding portion is arranged in contact with the heat receiving plate or with a gap so that the refrigerant stops at the refrigerant inlet side of the heat receiving space, thereby dividing the heat receiving space into the refrigerant inlet side and the refrigerant outlet side. This achieves the intended purpose.

As described above, the heat receiver of the present invention has a structure in which the heat receiving space is divided into the refrigerant inlet side and the refrigerant outlet side by the protruding portion. Therefore, the refrigerant supply in the width direction of the front surface of the heat receiving plate can be stabilized and the cooling efficiency can be increased.

That is, in the present invention, the refrigerant supplied from the refrigerant inlet side to the heat receiving space via the check valve first stops in a certain amount in the upper heat receiving space on the refrigerant inlet side. After that, it flows out in the width direction of the heat receiving plate, travels through the concave portion or convex portion on the vaporization portion side, is guided to the heat receiving plate side, and stops again with the heat receiving plate. Then, the refrigerant that is in contact with the heat receiving plate moves downward while being vaporized by the heat from the heating element. Further, since the protruding portion is arranged in contact with the heat receiving plate or with a gap so that the refrigerant stops at the refrigerant inlet side of the heat space, the passage area of the refrigerant in the protruding portion is small, and the protruding portion is in contact with the heat receiving plate. The speed of the refrigerant that moves downward while increasing is increased. As a result, the heat transfer coefficient of the refrigerant vaporized on the surface of the heat receiving plate is improved, and the heat receiver of the present invention can realize a large area and high cooling performance.

FIG. 1 is a perspective view of an electronic apparatus according to the first embodiment of the present invention. FIG. 2A is a front view showing a cooling part of the electronic device according to the first exemplary embodiment of the present invention. FIG. 2B is a side view showing the cooling part of the electronic device according to Embodiment 1 of the present invention. FIG. 3A is a plan view showing the cooling device for the electronic device according to the first exemplary embodiment of the present invention. FIG. 3B is a front view showing the electronic apparatus cooling device according to Embodiment 1 of the present invention. FIG. 3C is a side view showing the electronic apparatus cooling device according to the first exemplary embodiment of the present invention. FIG. 4A is a front view showing the electronic apparatus cooling device according to the first exemplary embodiment of the present invention. FIG. 4B is a perspective view illustrating the entire heat receiver of the cooling device for the electronic device according to the first exemplary embodiment of the present invention. FIG. 4C is a perspective view of the electronic device cooling device according to Embodiment 1 of the present invention with the heat receiver cover removed. FIG. 5A is a plan view showing the heat receiver of the cooling device for the electronic device according to the first exemplary embodiment of the present invention. FIG. 5B is a cross-sectional view showing a 5B-5B cross section of FIG. 5A of the heat receiver of the cooling device for the electronic device according to the first exemplary embodiment of the present invention. 5C is a cross-sectional view showing a 5C-5C cross section of FIG. 5A of the heat receiver of the cooling device for the electronic device according to the first exemplary embodiment of the present invention. FIG. 5D is a diagram illustrating details of a G section illustrated in FIG. 5B of the heat receiver of the cooling device for the electronic device according to the first embodiment of the present invention. FIG. 6A is a perspective view of the refrigerant distributor inside the heat receiver of the cooling device for the electronic device according to the first exemplary embodiment of the present invention. FIG. 6B is a front view of the refrigerant distributor inside the heat receiver of the cooling device for the electronic device according to the first exemplary embodiment of the present invention. FIG. 6C is a side view of the refrigerant distributor inside the heat receiver of the cooling device for the electronic device according to the first exemplary embodiment of the present invention. FIG. 7A is a perspective view of the refrigerant distributor inside the heat receiver of the cooling device according to the second exemplary embodiment of the present invention. FIG. 7B is a front view of the refrigerant distributor inside the heat receiver of the cooling device according to the second exemplary embodiment of the present invention. FIG. 7C is a side view of the refrigerant distributor inside the heat receiver of the cooling device according to the second exemplary embodiment of the present invention. FIG. 8A is a perspective view of the refrigerant distributor inside the heat receiver of the cooling device according to the third exemplary embodiment of the present invention. FIG. 8B is a front view of the refrigerant distributor inside the heat receiver of the cooling device according to the third exemplary embodiment of the present invention. FIG. 8C is a side view of the refrigerant distributor inside the heat receiver of the cooling device according to the third exemplary embodiment of the present invention. FIG. 9A is a front view showing a cooling device for an electronic device according to Embodiment 5 of the present invention. FIG. 9B is a side view showing the electronic apparatus cooling device according to the fifth exemplary embodiment of the present invention. FIG. 9C is a plan view showing the electronic apparatus cooling device according to Embodiment 5 of the present invention. FIG. 10A is a plan view illustrating the inside of the heat receiver of the electronic device according to the fifth exemplary embodiment of the present invention. FIG. 10B is a cross-sectional view taken along the line 10B-10B of FIG. 10A showing the heat receiver of the electronic device according to the fifth exemplary embodiment of the present invention. FIG. 11: is the top view which saw through the inside at the time of double-sided cooling of the heat receiver of the electronic device concerning Embodiment 5 of this invention. FIG. 12A is a plan view illustrating the inside of the heat receiver of the electronic device according to Embodiment 6 of the present invention. FIG. 12B is a cross-sectional view taken along the line 12B-12B in FIG. 12A showing the heat receiver of the electronic device according to the sixth exemplary embodiment of the present invention. 12C is a cross-sectional view of 12C-12C in FIG. 12A showing the heat receiver of the electronic device according to the sixth exemplary embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a perspective view of an electronic apparatus according to the first embodiment of the present invention. FIG. 1 shows a data center 1 in which a plurality of rack-type servers 2 are accommodated.

The rack-type server 2 has a rack housing having openings on the front side and the back side. Inside the rack housing, a plurality of electronic devices 3 are provided in a unit shape with an operation panel and a display unit facing the front side. On the back side, wirings and power lines for connecting the electronic devices 3 to each other or an external device are provided. A plurality of rack-type servers 2 are installed in the data center 1 and are generally called an electronic computer room or a server room as a whole.

FIG. 2A is a front view showing a cooling portion of the electronic device 3 according to the first exemplary embodiment of the present invention. FIG. 2B is a side view showing a cooling part of the electronic apparatus 3. As shown in FIGS. 2A and 2B, the rack-type server 2 has a predetermined horizontal direction with boards 5 having heating elements such as semiconductor elements standing vertically on each stage of the rack 4 casing. Arranged at intervals. The radiators 10 of the plurality of cooling devices 6 are installed in a heat exchangeable state with respect to the heat exchanger 13. Each radiator 10 is cooled by circulating cooling water from the external cooling tower 25 to the heat exchanger 13 via the pump 14.

FIG. 3A is a plan view showing the cooling device 6 of the electronic device 3 according to the first exemplary embodiment of the present invention. FIG. 3B is a front view showing the cooling device 6 of the electronic apparatus 3. FIG. 3C is a side view showing the cooling device 6 of the electronic apparatus 3. On the board 5, the heating element 7 is arranged in contact with the cooling device 6.

That is, as shown in FIGS. 3A and 3B, the heating element 7 is mounted on the board 5, and this is cooled by the cooling device 6.

Specifically, as shown in FIGS. 3A and 3B, the cooling device 6 includes a heat receiver 8 that is in contact with the heating element 7, a radiator 10 that is connected to the heat receiver 8 via a trachea 9, and this heat dissipation. And a check valve 12 connected to the vessel 10 via a liquid pipe 11.

By connecting the check valve 12 to the heat receiver 8, a circulation path that becomes the heat receiver 8, the trachea 9, the radiator 10, the liquid pipe 11, the check valve 12, and the heat receiver 8 is formed. The inside of the circulation path is in a reduced pressure state, and water is enclosed as an example of the refrigerant. The heat exchanger 13 cools the radiator 10.

Next, the internal structure of the heat receiver 8 of the cooling device 6 of the electronic apparatus 3 according to this embodiment will be described with reference to FIGS. 4A, 4B, and 4C. FIG. 4A is a front view showing the cooling device 6 of the electronic device 3 according to the first exemplary embodiment of the present invention. FIG. 4B is a perspective view showing the entire heat receiver 8 of the cooling device 6 of the electronic apparatus 3. FIG. 4C is a perspective view of the electronic device 3 with the cover of the heat receiver 8 of the cooling device 6 removed. As shown in FIG. 4C, the heat receiver 8 has a heat receiving plate 17 that makes contact with the heat generating body 7 and gradually heats, and a refrigerant vaporizes on the opposite side of the surface of the heat receiving plate 17 that contacts the heat generating body 7. There is a vaporization section 16 that takes heat away from the heat receiving plate 17. Furthermore, a heat receiving cover 18 that forms a heat receiving space so as to cover the vaporizing section 16 is disposed. Here, as shown in FIG. 4C, the surface of the vaporization portion 16 of the heat receiving plate 17 is provided with a vaporization promotion groove concave portion 17 a which is a plurality of groove portions for promoting efficient vaporization by increasing the surface area. ing.

Also, the heat receiving cover 18 is formed with a protruding portion 20 that protrudes toward the heat receiving plate 17 in the heat receiving space. The protrusion 20 divides the heat receiving space up and down into an upper heat receiving space 19a and a lower heat receiving space 19b. The refrigerant distributor 50 is arranged in the upper heat receiving space 19a so as to be close to the heat receiving plate 17. The protruding portion 20 protrudes into the plurality of vaporization promoting groove concave portions 17a of the heat receiving plate 17, or contacts the surface of the heat receiving plate 17 on the vaporizing portion 16 side so that the refrigerant stops in the upper heat receiving space 19a. Or are arranged with a gap. A refrigerant inlet 21 is provided on the side surface of the upper heat receiving space 19 a via the check valve 12. A refrigerant outlet 22 is provided on a side surface of the lower heat receiving space 19b. The refrigerant flowing into the heat receiver 8 from the check valve 12 temporarily stops in the refrigerant distributor 50 disposed inside the heat receiver 8, and then from a plurality of refrigerant outlets 51 provided in the heat receiver width direction. Evenly distributed in the heat receiver 8.

Next, with reference to FIGS. 5A, 5B, 5C, and 5D, the slow heat function in the heat receiver 8 and the refrigerant distributor 50 mounted in the upper heat receiving space 19a will be described while following the flow of the refrigerant. FIG. 5A is a plan view showing the heat receiver 8 of the cooling device 6 of the electronic device 3 according to the first exemplary embodiment of the present invention. 5B is a cross-sectional view showing a 5B-5B cross section of the heat receiver 8 of the cooling device 6 of the electronic apparatus 3 in FIG. 5A. FIG. 5C is a cross-sectional view showing a 5C-5C cross section of FIG. 5A of the heat receiver 8 of the cooling device 6 of the electronic apparatus 3. FIG. 5D is a diagram illustrating details of a G section illustrated in FIG. 5B of the heat receiver 8 of the cooling device 6 of the electronic apparatus 3.

5A and 5B, the refrigerant supplied to the heat receiver 8 flows from the refrigerant inlet 21 into the refrigerant distributor 50 in the upper heat receiving space 19a via the check valve 12. At this time, since the refrigerant distributor 50 has a function of holding a certain amount of refrigerant, the refrigerant temporarily stops as the primary holding liquid 53 shown in FIG. 5B. FIG. 5D shows the state of the primary stationary liquid 53 and the secondary stationary liquid 54 in detail.

Thereafter, the refrigerant flows out from each refrigerant outlet 51 almost uniformly in the heat receiving plate width direction. The refrigerant that has flowed out is guided to the vaporization section 16 side of the heat receiving plate 17 through the recess introduction path 52 provided on the side surface of the refrigerant distributor 50 in order to smoothly guide the refrigerant downward. The refrigerant is retained again as the secondary retention liquid 54 in the gap between the slope of the protrusion 20 of the heat receiving cover 18 and the heat receiving plate 17.

Thereafter, the refrigerant in contact with the vaporizing section 16 of the heat receiving plate 17 is boiled and vaporized by receiving heat from the heating element. For this reason, the pressure in the upper heat receiving space 19a increases due to the volume expansion of the refrigerant. The refrigerant becomes a high-speed multiphase flow accompanied by unboiling refrigerant, and creates a state of diffusing as a thin film-like refrigerant through the vaporization promoting groove recess 17a to the entire vaporization section 16 below. Since this high-speed multiphase flow has an increased transmission coefficient during vaporization, effective refrigerant vaporization is promoted, and as a result, it is possible to realize the heat receiver 8 that exhibits extremely high heat dissipation performance.

Next, in this part, after much of the circulating refrigerant is vaporized, it reaches the radiator 10 through the trachea 9 from the refrigerant outlet 22. Here, the refrigerant is liquefied by being cooled and releasing condensed heat to the heat exchanger 13. After liquefaction, the refrigerant returns to the upstream side of the check valve 12 again through the liquid pipe 11.

Continuous cooling is performed by repeating a series of cycles as described above.

The materials of the heat receiving plate 17 and the heat receiving cover 18 here are both metals having high thermal conductivity. For example, copper is desirable.

Next, the refrigerant distribution function of the refrigerant distributor 50 will be described in more detail with reference to FIGS. 6A, 6B, and 6C. FIG. 6A is a perspective view of the refrigerant distributor 50 inside the heat receiver 8 of the cooling device 6 of the electronic device 3 according to the first exemplary embodiment of the present invention. FIG. 6B is a front view of the refrigerant distributor 50 inside the heat receiver 8 of the cooling device 6 of the electronic apparatus 3. FIG. 6C is a side view of the refrigerant distributor 50 inside the heat receiver 8 of the cooling device 6 of the electronic apparatus 3.

6A, 6B, and 6C show that the refrigerant flows into the refrigerant distributor 50 from the direction of the solid arrow after passing through the check valve 12, and reaches the height of the refrigerant outlet 51 as a primary retaining liquid 53 for a fixed volume of refrigerant. Indicates the state of accumulation. When the refrigerant is further supplied to the primary stationary liquid 53, the same amount of refrigerant as the supplied refrigerant flows from the respective refrigerant outlets 51 in the width direction of the refrigerant distributor 50 as the outflow refrigerant 55 through the recess introduction path 52. It flows out evenly. The refrigerant that has flowed out due to this refrigerant distribution structure is retained in the gap between the heat receiving cover 18 and the heat receiving plate 17 in the upper heat receiving space, like the secondary retention liquid 54 in FIG. Evenly supplied. This makes it possible to realize a high-performance heat receiver that can supply a uniform refrigerant even with a wide and large heating element 7.

In the present embodiment, the shape of the refrigerant outlet 51 is circular.

Note that the refrigerant distributor 50 can be omitted.

As described above, the heat receiver 8 of the present embodiment is disposed on the heat receiving plate 17 having the heat receiving surface on one surface side and the vaporizing portion 16 on the other surface side of the heat receiving surface, and on the vaporizing portion 16 side of the heat receiving plate 17. And a heat receiving cover 18. Further, the heat receiving plate 17 and the heat receiving cover 18 form a heat receiving space. Moreover, the refrigerant | coolant inlet 21 is provided in the upper surface of heat receiving space, and the refrigerant | coolant outlet 22 is provided in the lower surface of heat receiving space. In addition, the refrigerant is supplied to the refrigerant inlet 21 through the check valve 12 into the heat receiving space, and the refrigerant flows out from the refrigerant outlet 22, and a plurality of parts in the vertical direction are provided on the vaporization section 16 side of the heat receiving plate 17. A recess 17a is provided. Further, the heat receiving cover 18 has a protruding portion 20 that protrudes toward the heat receiving plate 17 at a portion corresponding to the vaporizing portion 16. Further, the protruding portion 20 is arranged in contact with the heat receiving plate 17 or with a gap so that the refrigerant stops at the refrigerant inlet side of the heat receiving space, thereby dividing the heat receiving space into the refrigerant inlet 21 side and the refrigerant outlet 22 side. ing.

Thereby, the refrigerant supply in the width direction of the front surface of the heat receiving plate 17 can be stabilized and the cooling efficiency can be improved. Therefore, the heat receiver 8 of the present embodiment can achieve a large area and high cooling performance.

Further, the refrigerant distributor 50 having a plurality of refrigerant outlets 22 in the heat receiving space on the refrigerant inlet 21 side may be arranged in contact with either the heat receiving plate 17 or the heat receiving cover 18. Thereby, even if it is the wide and large area heat generating body 7, the high performance heat receiver which can supply a uniform refrigerant | coolant is realizable.

In addition, the cooling device 6 of the present embodiment connects the radiator 10 to the refrigerant outlet 22 of the vaporization unit 16 in the heat receiver 8 via the first pipe line corresponding to the trachea 9, and the liquid is connected to the radiator 10. A check valve 12 may be connected via a second pipe line corresponding to the pipe 11, and the refrigerant inlet 21 of the vaporization section 16 in the heat receiver 8 may be connected to the check valve 12 to constitute a circulation path. Further, the refrigerant may be sealed with the inside of the circulation path in a reduced pressure state. Thereby, the cooling performance of the cooling device 6 can be improved and the operational stability can be ensured.

Further, in the electronic device 3 of the present embodiment, the heating element 7 may be brought into contact with the heat receiving plate 17 constituting the heat receiver 8 of the cooling device 6. Thereby, the heat generating body 7 can be cooled efficiently.

(Embodiment 2)
The refrigerant distributor 50 of the cooling device according to the second embodiment of the present invention will be described with reference to FIGS. 7A, 7B, and 7C. FIG. 7A is a perspective view of the refrigerant distributor 50 inside the heat receiver 8 of the cooling device 6 according to the second embodiment of the present invention. FIG. 7B is a front view of the refrigerant distributor 50 inside the heat receiver 8 of the cooling device 6. FIG. 7C is a side view of the refrigerant distributor 50 inside the heat receiver 8 of the cooling device 6. FIG. 7C shows the state of the primary retention liquid 53 in detail.

The refrigerant distributor 50 of the present embodiment has a structure in which the upper part of the cylindrical refrigerant distributor 50 shown in FIGS. 6A and 6B is cut. The refrigerant distributor 50 of the present embodiment has a refrigerant distribution function substantially equivalent to the case of FIGS. 6A and 6B. In the refrigerant distributor 50 of the present embodiment, the outlet shape of the refrigerant outlet 51 is particularly rectangular, and is parallel to the stationary liquid surface. Therefore, it becomes the structure which is easy to maintain the uniformity of refrigerant distribution. In addition, with this structure, a normal sheet metal construction method can be adopted, so that it is easy to manufacture. Therefore, the refrigerant distributor 50 of the present embodiment can greatly contribute to cost reduction by reducing the number of steps.

(Embodiment 3)
A refrigerant distributor 50 of the cooling device 6 according to the third embodiment of the present invention will be described with reference to FIGS. 8A, 8B, and 8C. FIG. 8A is a perspective view of the refrigerant distributor 50 inside the heat receiver 8 of the cooling device 6 according to the third embodiment of the present invention. FIG. 8B is a front view of the refrigerant distributor 50 inside the heat receiver 8 of the cooling device 6. FIG. 8C is a side view of the refrigerant distributor 50 inside the heat receiver 8 of the cooling device 6. FIG. 8C shows the state of the primary retention liquid 53 in detail.

The refrigerant distributor 50 according to the present embodiment has substantially the same structure as the refrigerant distributor according to the second embodiment. The refrigerant distributor 50 of the present embodiment has a refrigerant distribution function substantially equivalent to that of the refrigerant distributor of the second embodiment. In the refrigerant distributor 50 of the present embodiment, the outlet shape of the refrigerant outlet 51 is particularly wedge-shaped. With this structure, fluctuations in the amount of outflow due to the refrigerant surface tension are suppressed, and the uniformity of refrigerant distribution is easily maintained. Also in this case, the ease of manufacture and the cost are the same as those of the refrigerant distributor of the second embodiment.

As described above, the shape of the refrigerant outlet of the refrigerant distributor according to the first to third embodiments is any of a circle, a rectangle, and a wedge. Thereby, the fluctuation | variation of the outflow amount by refrigerant | coolant surface tension is suppressed, and it is easy to maintain the uniformity of refrigerant distribution. In addition, with this structure, a normal sheet metal construction method can be adopted, so that it is easy to manufacture. Therefore, it can greatly contribute to cost reduction by reducing man-hours.

(Embodiment 4)
The surface shape of the vaporization part 16 of the cooling device 6 in Embodiment 4 of this invention is demonstrated using FIG. 4C. The shape of the vaporization portion 16 in FIG. 4C has been described as the vaporization promotion groove recess portion 17a in the first embodiment. However, it does not necessarily have to be recessed from the substrate surface. Even with a vaporization promoting convex portion (fin shape) having a protruding shape, it is possible to ensure substantially the same cooling performance as the vaporization promoting groove concave portion.

As described above, the heat receiver 8 of the present embodiment is disposed on the heat receiving plate 17 having the heat receiving surface on one surface side and the vaporizing portion 16 on the other surface side of the heat receiving surface, and on the vaporizing portion 16 side of the heat receiving plate 17. And a heat receiving cover 18. Further, the heat receiving plate 17 and the heat receiving cover 18 form a heat receiving space. Moreover, the refrigerant | coolant inlet 21 is provided in the upper surface of heat receiving space, and the refrigerant | coolant outlet 22 is provided in the lower surface of heat receiving space. In addition, the refrigerant is supplied to the refrigerant inlet 21 through the check valve 12 into the heat receiving space, and the refrigerant flows out from the refrigerant outlet 22, and a plurality of parts in the vertical direction are provided on the vaporization section 16 side of the heat receiving plate 17. Protrusions are provided. Further, the heat receiving cover 18 has a protruding portion 20 that protrudes toward the heat receiving plate 17 at a portion corresponding to the vaporizing portion 16. Further, the protruding portion 20 is arranged in contact with the heat receiving plate 17 or with a gap so that the refrigerant stops at the refrigerant inlet side of the heat receiving space, thereby dividing the heat receiving space into the refrigerant inlet 21 side and the refrigerant outlet 22 side. ing.

Thereby, the refrigerant supply in the width direction of the front surface of the heat receiving plate 17 can be stabilized and the cooling efficiency can be improved. Therefore, the heat receiver 8 of the present embodiment can achieve a large area and high cooling performance.

(Embodiment 5)
The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

The electronic device 3 according to the present embodiment is the same as that described in the first embodiment and is the same as that shown in FIG. The cooling part of the electronic device 3 of the present embodiment is the same as that described in the first embodiment and is the same as that shown in FIGS. 2A and 2B.

FIG. 9A is a front view showing the cooling device 6 of the electronic device 3 according to the fifth exemplary embodiment of the present invention. FIG. 9B is a side view showing the cooling device 6 of the electronic apparatus 3. FIG. 9C is a plan view showing the cooling device 6 of the electronic apparatus 3. FIG. 10A is a plan view illustrating the inside of the heat receiver 8 of the electronic apparatus 3 as seen through. 10B is a cross-sectional view of the heat receiver 8 of the electronic device 3 taken along the line 10B-10B in FIG. 10A.

Each board 5 is provided with a cooling device 6 shown in FIGS. 9A and 9C.

As shown in FIGS. 9A and 9C, a plurality of semiconductor elements 27 (an example of a heating element) are mounted on each board 5. The cooling device 6 cools the plurality of semiconductor elements 27.

Specifically, as shown in FIGS. 9A and 9C, the cooling device 6 includes a heat receiver 8 that is in contact with the semiconductor element 27, a heat radiator 10 that is connected to the heat receiver 8 via a conduit 9, And a check valve 12 connected to the vessel 10 via a conduit 11.

By connecting the check valve 12 to the heat receiver 8, a circulation path that connects the heat receiver 8, the pipe 9, the radiator 10, the pipe 11, the check valve 12, and the heat receiver 8 is formed. The circulation path is depressurized, and water as an example of a refrigerant is enclosed.

As shown in FIGS. 10A and 10B, the heat receiver 8 used in the present embodiment includes a heat receiving portion 15 that contacts the semiconductor element 27 on one surface side, and a vaporizing portion on a portion corresponding to the heat receiving portion 15 on the other surface side. The heat receiving plate 17 having 16 and the heat receiving cover 18 disposed on the vaporization unit 16 side of the heat receiving plate 17 are provided. A heat receiving space 19 is formed by the heat receiving plate 17 and the heat receiving cover 18.

The heat receiving cover 18 has a protruding portion 20 that protrudes toward the heat receiving plate 17 in the heat receiving space 19. The protrusion 20 protrudes into the plurality of vaporization promoting groove recesses 17 a of the heat receiving plate 17. A refrigerant inlet 21 is provided above the heat receiving space 19, and a refrigerant outlet 22 is provided below the heat receiving space 19.

The liquid refrigerant is supplied to the refrigerant inlet 21 of the heat receiver 8 via the check valve 12. From the refrigerant outlet 22, a liquid refrigerant and a gaseous refrigerant flow out to the conduit 9.

The closest portion 20a of the protruding portion 20 to the heat receiving plate 17 has a portion 20b parallel to the vaporization promoting convex portion 17b of the plurality of vaporization promoting groove concave portions 17a in a substantially vertical direction. The portions 20b parallel to the vaporization promoting convex portions 17b are separated by a gap of about 1 mm, for example. This gap serves as a passage for the liquid refrigerant.

Further, θ> α is preferable, where θ and α are angles extending from both ends of the parallel portion 20b of the protruding portion 20 to the refrigerant inlet 21 side and the refrigerant outlet 22 side, respectively. α is preferably smaller in order for the liquid refrigerant to move in contact with the heat receiving plate 17, but a certain amount of passage space for the gaseous refrigerant is also required. Therefore, α is, for example, about 20 to 30 degrees as shown in FIG. 10B.

Further, as shown in FIG. 10A, the heat receiving space 19 gradually extends in the horizontal direction parallel to the heat receiving plate 17 from the refrigerant inlet 21 side to the middle part between the refrigerant inlet 21 and the refrigerant outlet 22. The space from the coolant outlet 22 gradually narrows in the horizontal direction parallel to the heat receiving plate 17.

Here, both the heat receiving plate 17 and the heat receiving cover 18 are made of metal, for example, copper.

In the above configuration, when the liquid refrigerant is supplied from the refrigerant inlet 21 of the heat receiver 8 through the check valve 12 and flows into the plurality of vaporization promotion groove recesses 17a of the heat receiving plate 17, the heat from the semiconductor element 27 is received. The liquid refrigerant begins to vaporize immediately.

At this time, the liquid refrigerant passage is formed with a gap of about 1 mm, for example, by the protrusion 20 of the heat receiving cover 18 of the heat receiver 8. Therefore, due to the expansion pressure generated on the refrigerant inlet 21 side with respect to the protrusion 20, the liquid refrigerant and the gaseous refrigerant vigorously flow into the vaporization section 16 in the plurality of vaporization promotion groove recesses 17 a of the heat receiving plate 17. At the same time, vaporization of the liquid refrigerant proceeds.

Here, most of the liquid refrigerant is vaporized and reaches the radiator 10 from the refrigerant outlet 22 through the conduit 9. The vaporized refrigerant is cooled and liquefied by the radiator 10 and returns to the upstream side of the check valve 12 via the pipe line 11.

In the above situation, in this embodiment, the closest portion 20a of the protrusion 20 to the heat receiving plate 17 has a portion 20b parallel to the vaporization promotion convex portions 17b of the plurality of vaporization promotion groove concave portions 17a in a substantially vertical direction. is doing. Thereby, the liquid refrigerant that has passed through the gap between the portion 20b parallel to the vaporization promotion convex portions 17b of the plurality of vaporization promotion groove concave portions 17a has a larger downward vector than when there is no parallel portion 20b, and the heat receiving plate 17 It becomes easy to pass through the plurality of vaporization promoting groove recesses 17a toward the refrigerant outlet 22 side.

Furthermore, the shape of the protrusion 20 of the heat receiver 8 is such that the angle α spreading toward the refrigerant outlet 22 is smaller than the angle θ spreading toward the refrigerant inlet 21 from both ends of the parallel portion 20b of the protrusion 20. The liquid refrigerant and the gaseous refrigerant heated by the heat receiving plate 17 can more easily pass through the plurality of vaporization promoting groove concave portions 17a of the heat receiving plate 17.

That is, the liquid refrigerant moves downward while being in contact with the heat receiving plate 17 heated by the heat generation of the semiconductor element 27, so that most of the liquid refrigerant absorbs heat and becomes a gaseous refrigerant. Can be cooled.

Further, by positioning the upper end of the parallel portion 20b of the protruding portion 20 below the upper end of the semiconductor element 27, the liquid refrigerant that has flowed into the plurality of vaporization promoting groove concave portions 17a on the refrigerant inlet 21 side of the protruding portion 20 is a semiconductor. Heat is absorbed from the heat receiving plate 17 heated by the heat generated by the element 27, and is easily changed to a gaseous refrigerant. Expansion pressure is generated by evaporation of the refrigerant. The refrigerant in which the liquid refrigerant and the gaseous refrigerant are mixed moves downward more vigorously through the gap between the portion 20b parallel to the vaporization promotion convex portion 17b.

Also, the space from the refrigerant inlet 21 side to the middle part between the refrigerant inlet 21 and the refrigerant outlet 22 has a space that gradually spreads in the direction perpendicular to the refrigerant flow, as can be seen from FIG. 10A. Between the middle part and the refrigerant outlet 22, there is a space that gradually narrows in the direction perpendicular to the refrigerant flow. For this reason, the liquid refrigerant is smoothly supplied from the refrigerant inlet 21 side to the vaporization section 16 via the check valve 12. Further, the gaseous refrigerant and the liquid refrigerant vaporized in the vaporizing section 16 smoothly travel from the vaporizing section 16 to the refrigerant outlet 22. As a result, the speed of the refrigerant flowing through the vaporizing unit 16 is increased. Therefore, the cooling efficiency can be increased.

FIG. 11 is a plan view illustrating the inside of the heat receiver 8 of the electronic device 3 according to the fifth embodiment of the present invention when both sides are cooled. As shown in FIG. 11, the heat receiver 8 shown in FIG. 10A can easily cope with double-sided cooling.

In the present embodiment, the heat receiving cover 18 is described as a block shape, but may be formed in a plate shape as indicated by a broken line in FIG. 10B. Although processing of a board becomes complicated, weight reduction can be achieved compared with a block shape.

Further, in the present embodiment, the configuration in which the closest portion 20a of the protruding portion 20 to the heat receiving plate 17 is protruded into the plurality of vaporization promoting groove concave portions 17a has been described. However, even if the depth of the plurality of vaporization promoting groove recesses 17a is reduced, if there is no problem as a heat transfer area, the closest portion 20a is not projected, and the top surface of the plurality of vaporization promotion groove recesses 17a is flush with the top surface. Good. In this case, it is not necessary to perform uneven processing on the tip of the protruding portion 20 of the heat receiving cover 18. Therefore, it has the merit at the time of manufacture.

As described above, in the heat receiver 8 of the present embodiment, the closest part to the heat receiving plate of the protrusion is flush with the top surfaces of the plurality of recesses, and the closest part is the bottom surface of the plurality of recesses. A portion parallel to the top surface may be provided in a substantially vertical direction. Thereby, the uneven | corrugated process of the front-end | tip of the protrusion part 20 of the heat receiving cover 18 becomes unnecessary. Therefore, it has the merit at the time of manufacture.

In addition, the heat receiving space 19 has a shape extending in a direction parallel to the heat receiving plate 17 between the refrigerant inlet 21 and the refrigerant outlet 22, and extends in a direction parallel to the heat receiving plate 17 from the middle to the refrigerant outlet 22. The shape may be narrowed. Thereby, the liquid refrigerant is smoothly supplied from the refrigerant inlet 21 side to the vaporization section 16 via the check valve 12. Further, the gaseous refrigerant and the liquid refrigerant vaporized in the vaporizing section 16 smoothly travel from the vaporizing section 16 to the refrigerant outlet 22. As a result, the speed of the refrigerant flowing through the vaporizing unit 16 is increased. Therefore, the cooling efficiency can be increased.

Further, the heating element may be the semiconductor element 27. Thereby, the semiconductor element 27 can be efficiently cooled.

(Embodiment 6)
In the present embodiment, the heat receiver 8 of the fifth embodiment is a box-shaped heat receiver 30, and the protruding portion 20 is configured as a separate member from the heat receiving cover 18, and a plurality of them instead of the plurality of vaporization promoting groove concave portions 17 a. This is a convex portion 33a. Constituent elements similar to those of the fifth embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

FIG. 12A is a plan view of the inside of the heat receiver 30 of the electronic device 3 according to the sixth exemplary embodiment of the present invention. 12B is a cross-sectional view taken along the line 12B-12B of FIG. 12A showing the heat receiver 30 of the electronic device 3. FIG. 12C is a cross-sectional view taken along the line 12C-12C in FIG. 12A showing the heat receiver 30 of the electronic device 3. FIG.

As shown in FIGS. 12A, 12B, and 12C, the heat receiver 30 has a heat receiving portion 31 that is in contact with the semiconductor element 27 on one surface side, and a vaporizing portion 32 in a portion corresponding to the heat receiving portion 31 on the other surface side. A heat receiving plate 33 and a heat receiving cover 34 disposed on the vaporizing section 32 side of the heat receiving plate 33 are provided.

Also, the heat receiving cover 34 is provided with a protrusion 36 having a U-shaped cross section protruding into the heat receiving plate 33 in the heat receiving space 35. The heat receiving plate 33 is provided with a plurality of convex portions 33a. A refrigerant inlet 37 is provided in the upper part of the heat receiving space 35. A refrigerant outlet 38 is provided in the lower part of the heat receiving space.

Further, the closest part 36a of the projecting part 36 enters the plurality of convex parts 33a and has a part 36b parallel to the heat receiving plate 33 in a substantially vertical direction, as in the fifth embodiment. The portion 36b parallel to the heat receiving plate 33 is separated from the heat receiving plate 33 by a gap of about 1 mm, for example, and this gap serves as a passage for the liquid refrigerant.

For this reason, liquid refrigerant is supplied to the refrigerant inlet 37 of the heat receiver 30 via the check valve 12, and liquid refrigerant and gaseous refrigerant flow out from the refrigerant outlet 38 to the conduit 9.

In the above configuration, since the heat receiver 30 has a box shape and the heat receiving cover 34 also has a simple lid shape, it is easier to manufacture than the heat receiver 8 of FIG. 10A of the fifth embodiment.

Further, since the projecting portion 36 is inclined downward from the heat receiving cover 34 side to the heat receiving plate 33 side, the liquid refrigerant supplied from the refrigerant inlet 37 to the heat receiving space 35 via the check valve 12 is transferred to the heat receiving plate. It flows down to the 33 side and contacts the plurality of convex portions 33 a and the heat receiving plate 33.

Since the subsequent operation of the liquid refrigerant is the same as that in the fifth embodiment, detailed description thereof is omitted.

As can be seen from a comparison between FIGS. 10A and 10B and FIGS. 12A and 12B, the width of the heat receiving space 35 below the protrusion 36, which is the difference between the fifth embodiment and the present embodiment, is the protrusion 36. By adjusting the length of the portion 36b parallel to the heat receiving plate 33, the demerit of the heat receiving space 35 of FIGS. 12A and 12B, which is wider than FIGS. 10A and 10B, can be eliminated.

In the present embodiment, the closest portion 36a of the heat receiving cover 34 of the protrusion 36 is inserted into the plurality of protrusions 33a. However, even if the depth of the plurality of protrusions 33a is reduced, the heat transfer area is reduced. If there is no problem, the closest portion 36a may be flush with the top surfaces of the plurality of convex portions 33a without entering. In this case, it is not necessary to process the top and bottom of the protrusion 36. Therefore, it has the merit at the time of manufacture.

In the fifth embodiment, when the heat receiving cover 18 and the projecting portion 20 are integrated and the vaporization promoting groove concave portion 17a is provided in the heat receiving plate 17, in the sixth embodiment, the heat receiving cover 34 and the projecting portion 36 receive heat by separate members. The case where the convex part 33a was provided in the board 33 was demonstrated. However, when the heat receiving cover 18 and the protruding portion 20 are integrated with the heat receiving plate 33 and the convex portion 33a is provided, and when the heat receiving cover 34 and the protruding portion 36 are separate members and the heat receiving plate 17 is provided with the vaporization promoting groove concave portion 17a. Also, the effects described in the fifth embodiment are provided.

As described above, in the heat receiver 30 of the present embodiment, the closest portion of the protruding portion to the heat receiving plate is flush with the top surface of the plurality of convex portions 33a, and the closest portion is the plurality of convex portions. A portion parallel to the top surface of the bottom surface of 33a may be provided in a substantially vertical direction. Thereby, the uneven | corrugated process of the front-end | tip of the protrusion part 20 of the heat receiving cover 18 becomes unnecessary. Therefore, it has the merit at the time of manufacture.

As described above, the heat receiver of the present invention can realize a large area and high cooling performance. Further, it is useful as a cooling device using a heat receiver and an electronic device using the cooling device using the heat receiver.

DESCRIPTION OF SYMBOLS 1 Data center 2 Server 3 Electronic device 4 Rack 5 Board 6 Cooling device 7 Heat generating body 8 Heat receiving device 9 Air pipe 10 Radiator 11 Liquid tube 12 Check valve 13 Heat exchanger 14 Pump 15 Heat receiving portion 16 Vaporizing portion 17 Heat receiving plate 17a Vaporization Promotion groove concave portion 17b Evaporation promotion convex portion 18 Heat receiving cover 19 Heat receiving space 19a Upper heat receiving space 19b Lower heat receiving space 20 Protruding portion 20a Nearest portion 20b Parallel portion 21 Refrigerant inlet 22 Refrigerant outlet 25 External cooling tower 27 Semiconductor element 30 Heat receiver 31 Heat receiving portion 32 Vaporizing portion 33 Heat receiving plate 33a Protruding portion 34 Heat receiving cover 35 Heat receiving space 36 Protruding portion 36a Closest portion 36b Parallel portion 37 Refrigerant inlet 38 Refrigerant outlet 50 Refrigerant distributor 51 Refrigerant outlet 52 Recessed inlet passage 53 Primary stop Liquid 54 Secondary retention liquid 55 Flow Refrigerant

Claims (8)

A heat receiving surface having a heat receiving surface on one surface side, and a vaporizing portion on the other surface side of the heat receiving surface;
A heat receiving cover disposed on the vaporization part side of the heat receiving plate,
A heat receiving space is formed by the heat receiving plate and the heat receiving cover,
A refrigerant inlet is provided on the upper surface of the heat receiving space, and a refrigerant outlet is provided on the lower surface of the heat receiving space,
Refrigerant is supplied to the refrigerant inlet through the check valve into the heat receiving space, and the refrigerant flows out of the refrigerant outlet.
A plurality of concave or convex portions are provided in the vertical direction on the vaporization portion side of the heat receiving plate,
The heat receiving cover has a protruding portion protruding toward the heat receiving plate in a portion corresponding to the vaporizing portion,
The projecting portion is arranged in contact with the heat receiving plate or with a gap so that the refrigerant stays on the refrigerant inlet side of the heat receiving space, so that the heat receiving space is placed on the refrigerant inlet side and the refrigerant outlet side. Divided heat receiver. The heat receiver according to claim 1, wherein a refrigerant distributor having a plurality of refrigerant outlets in the heat receiving space on the refrigerant inlet side is disposed in contact with either the heat receiving plate or the heat receiving cover. The heat receiver according to claim 2, wherein a shape of the refrigerant outlet of the refrigerant distributor is any one of a circular shape, a rectangular shape, and a wedge shape. The closest part of the protrusion to the heat receiving plate is flush with the top surface of the plurality of recesses or protrusions,
2. The heat receiver according to claim 1, wherein the closest portion has a portion parallel to a bottom surface of the plurality of concave portions or a top surface of the convex portion in a substantially vertical direction. The heat receiving space has a shape extending in a direction parallel to the heat receiving plate between the refrigerant inlet and the refrigerant outlet, and narrows in a direction parallel to the heat receiving plate from the middle to the refrigerant outlet. The heat receiver according to claim 1, which has a shape. A radiator is connected to the refrigerant outlet of the vaporization unit in the heat receiver according to any one of claims 1 to 5 via a first pipe line,
A check valve is connected to the radiator via a second conduit;
While connecting the refrigerant inlet of the vaporization part in the heat receiver to the check valve to constitute a circulation path,
A cooling device in which a refrigerant is sealed with the inside of the circulation path in a reduced pressure state. The electronic device which made the heat generating body contact | abut to the heat receiving plate which comprises the said heat receiver of the said cooling device of Claim 6. The electronic device according to claim 7, wherein the heating element is a semiconductor element.

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