JP2017096589A - Cooling device and electronic equipment mounting the same, and electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling device which stably repeats a cooling cycle, which does not deteriorate cooling performance and which can cool a heat generator, by suppressing accumulation of a liquefied refrigerant in a heat radiation part.SOLUTION: A cooling device 3 includes a heat receiving part 4 including a heat receiving plate 11 for transmitting heat to a working fluid 12, a heat radiation part 5 for discharging heat of the working fluid 12, and a heat radiation path 6 and a return path 7 for connecting the heat receiving part 4 and the heat radiation part 5, and it performs transfer of heat by circulating the working fluid 12 in the heat receiving part 4, the heat radiation path 6, the heat radiation part 5, the return path 7 and to the heat receiving part 4. An inflow tube 19 protruding in the heat receiving part 4 is provided on the heat receiving part 4 side of the return path 7, and a check valve 18 is provided at the return path 7 or the inflow tube 19. The heat radiation part 5 laminates hairpin tubes 21 penetrating heat radiation fins 20. The flow passage of the working fluid 12 in the hairpin tubes 21 are arranged to incline downward, and shielding bodies are inserted in gaps of the heat radiation fins 20 opposing to curved parts of the hairpin tubes 21.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a cooling device, an electronic device equipped with the cooling device, and an electric vehicle.

  Conventionally, this type of cooling device is known to be mounted on a power conversion circuit of an electric vehicle. In an electric vehicle, an electric motor serving as a driving power source is switched by an inverter circuit that is a power conversion circuit. A plurality of semiconductor switching elements represented by power transistors are used in the inverter circuit, and a large current of several tens of amperes flows through each element. Therefore, the semiconductor switching element generates a large amount of heat, and a high-performance cooling device is necessary. Therefore, conventionally, in a boiling cooling device provided with a heat receiving portion that receives heat generated from the switching element, a heat radiating portion having a horizontal pipe above the heat receiving portion, a heat receiving portion, and a circulation path that connects the heat radiating portions. The switching element was cooled (see, for example, Patent Document 1).

  Such a conventional cooling device employs a method of removing heat from the switching element by latent heat generated by contacting the semiconductor switching element and vaporizing the liquid refrigerant in the heat receiving portion. Specifically, the vaporized refrigerant rises to the radiator disposed above, and is then cooled and condensed by the wall surface in the radiator to liquefy again. Next, cooling of the liquefied refrigerant is continued by continuously repeating a cycle in which the liquefied refrigerant moves downward along the tube wall surface of the circulation path and again takes heat from the element and vaporizes.

  Generally, the heat removed when cooling a semiconductor switching element or the like, which is a heating element having a high calorific value, is finally radiated from a heat radiating portion having a large area to the air.

JP-A-4-139368

  However, in such a heat radiating section, the condensed liquefied refrigerant stays in the horizontal piping of the heat radiating section, so that the refrigerant does not circulate and the above cycle does not rotate, and the cooling performance is significantly reduced. It was.

  Therefore, the present invention provides a cooling device capable of stably repeating a cooling cycle and cooling a heating element without degrading the cooling performance by suppressing the retention of the liquefied refrigerant in the heat radiating section. It is the purpose.

  In order to achieve this object, the present invention provides a heat receiving portion including a heat receiving plate that transfers heat from the heating element to the working fluid, a heat radiating portion that releases the heat of the working fluid, the heat receiving portion, and the heat receiving portion. Cooling that includes a heat dissipation path and a return path for connecting to the heat dissipation section, and circulates the working fluid to the heat receiving section, the heat dissipation path, the heat dissipation section, the return path, and the heat receiving section to transfer heat. The apparatus includes an inflow pipe projecting into the heat receiving section from a connection portion between the return path and the heat receiving section, and a check valve is provided in the return path or the inflow pipe, and the heat radiating section includes a plurality of heat radiating fins. The hairpin tube is configured such that the flow path of the working fluid is downwardly inclined, and a shield is inserted into the gap of the heat radiating fin facing the curved portion of the hairpin tube, This achieves the intended purpose. It is intended.

  According to the present invention, a heat receiving portion including a heat receiving plate that transfers heat from the heat generating element to the working fluid, a heat radiating portion that releases the heat of the working fluid, and a heat radiating path that connects the heat receiving portion and the heat radiating portion. And a return path, wherein the working fluid is circulated to the heat receiving part, the heat radiating path, the heat radiating part, the feedback path, and the heat receiving part to transfer heat, and the return path And an inflow pipe projecting into the heat receiving part from a connection part between the heat receiving part, a check valve is provided in the return path or the inflow pipe, the heat radiating part is provided with a hairpin pipe having a plurality of heat radiating fins, The hairpin tube is configured such that the flow path of the working fluid has a downward slope, and is configured such that a shield is inserted into the gap of the heat radiating fin facing the curved portion of the hairpin tube. This reduces the cooling performance There is provided a cooling device which can cool a heating element without.

  In other words, the heat dissipating part includes a hairpin tube having a plurality of heat dissipating fins, and the hairpin tube is configured so that the flow path of the working fluid has a downward slope, whereby the liquefied refrigerant cooled and condensed by the tube wall of the hairpin tube It flows downward along a downwardly inclined channel without staying. As a result, by suppressing the retention of the liquefied refrigerant in the heat radiating section, a cooling device capable of stably repeating the cooling cycle and cooling the heating element without degrading the cooling performance is provided.

  Further, by inserting a shielding body into the gap of the radiating fin facing the curved portion of the hairpin tube, the gap of the radiating fin in the portion through which the cooling air for cooling the radiating section passes, that is, the lower end of the upper radiating fin And the gap existing at the upper end of the radiating fin below the radiating fin is reduced, so that the cooling air does not flow unevenly into the vacant part with less pressure loss and can efficiently pass between the radiating fins. it can. When the cooling air flows into the gap between the radiating fins, the cooling air passes through the radiating portion without receiving heat from the radiating fins, so that the cooling efficiency is lowered. By preventing the air from flowing into the gaps between the fins, it is possible to prevent a decrease in cooling efficiency. As a result, it is possible to provide a cooling device that can cool the heating element continuously and stably and can cool the heating element without deteriorating the cooling performance.

Schematic of the electric vehicle according to the first embodiment of the present invention. Schematic showing the cooling system (A) Configuration diagram before processing of heat radiating portion of cooling device, (b) Configuration diagram after processing of heat radiating portion of cooling device Detailed cross-sectional view of the heat dissipating fin and the shield of the heat dissipating part of the cooling device

  A heat receiving portion having a heat receiving plate for transmitting heat from the heating element to the working fluid; a heat radiating portion that releases heat of the working fluid; a heat radiating path that connects the heat receiving portion and the heat radiating portion; and a feedback path. A cooling device that circulates the working fluid to the heat receiving part, the heat radiating path, the heat radiating part, the return path, and the heat receiving part to move heat, the return path and the heat receiving part side; An inflow pipe projecting into the heat receiving part from the connection part, and a check valve is provided in the return path or the inflow pipe, the heat radiating part is provided with a hairpin pipe having a plurality of radiating fins, and the hairpin pipe is operated The fluid flow path is configured to have a downward slope, and the shield is inserted into the gap of the radiating fin facing the curved portion of the hairpin tube, so that the heating element can be mounted without reducing the cooling performance. Cooling device that can be cooled It is intended to provide.

  In other words, the heat dissipating part includes a hairpin tube having a plurality of heat dissipating fins, and the hairpin tube is configured so that the flow path of the working fluid has a downward slope, whereby the liquefied refrigerant cooled and condensed by the tube wall of the hairpin tube It flows downward along a downwardly inclined channel without staying. As a result, by suppressing the retention of the liquefied refrigerant in the heat radiating section, a cooling device capable of stably repeating the cooling cycle and cooling the heating element without degrading the cooling performance is provided.

  Furthermore, by inserting a shielding body into the gap of the radiation fin facing the curved portion of the hairpin tube, the gap of the radiation fin in the part through which the cooling air for cooling the radiation part passes, that is, the lower end of the upper radiation fin and By reducing the gap that exists at the upper end of the radiating fin below the radiating fin, cooling air can be efficiently passed between the radiating fins without flowing into the gap with little pressure loss. . When the cooling air flows into the gap between the radiating fins, the cooling air passes through the radiating portion without receiving heat from the radiating fins, so that the cooling efficiency is lowered. By preventing the air from flowing into the gaps between the fins, it is possible to prevent a decrease in cooling efficiency. As a result, it is possible to provide a cooling device that can cool the heating element continuously and stably and can cool the heating element without deteriorating the cooling performance.

  Moreover, the said shielding body is good also as a structure which has the protrusion part which protruded facing the inflow direction of the cooling air which cools the said thermal radiation part. With this configuration, the cooling air toward the shield can smoothly flow between the heat radiating fins along the protruding portion of the shield. Therefore, the cooling air can efficiently pass between the radiating fins. Therefore, the pressure loss due to the movement of the cooling air does not increase, and the efficiency of cooling the radiating fins does not decrease. As a result, the cooling of the heating element is repeated continuously and the cooling performance is lowered. Therefore, it is possible to provide a cooling device that can cool the heating element.

  Moreover, the said shielding body is good also as a structure which has the other protrusion part which protrudes in the reverse direction to the direction where the said protrusion part protrudes. With this configuration, even if the cooling air is sucked from any of the heat radiation fins into which the shield is inserted, that is, even when the direction in which the cooling air flows is reversed, the cooling air flows into the protruding portion of the shield. It can flow smoothly between the radiating fins. Therefore, the cooling air can efficiently pass between the radiating fins. Therefore, the pressure loss due to the movement of the cooling air does not increase, and the efficiency of cooling the radiating fins does not decrease. As a result, the cooling of the heating element is repeated continuously and the cooling performance is lowered. Therefore, it is possible to provide a cooling device that can cool the heating element.

  Moreover, you may make it the structure of the electronic device carrying the cooling device of this invention. Thereby, it can be set as the electronic device which cools a heat generating body with the cooling device in which the efficiency at the time of cooling a radiation fin does not fall.

  Moreover, you may make it the structure of the electric vehicle carrying the cooling device of this invention. Thereby, it can be set as the electric vehicle which cools a heat generating body with the cooling device in which the efficiency at the time of cooling a radiation fin does not fall.

(Embodiment 1)
Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, an electric motor (not shown) that drives an axle (not shown) of an electric vehicle 1 is connected to an inverter circuit 2 that is a power conversion device arranged in the electric vehicle 1.

  The inverter circuit 2 supplies electric power to the electric motor, and includes a plurality of semiconductor switching elements (10 in FIG. 2). The semiconductor switching elements (10 in FIG. 2) generate heat during operation. For this reason, in order to cool this semiconductor switching element (10 in FIG. 2), a cooling device 3 is provided. The cooling device 3 includes a heat receiving portion 4 and a heat radiating portion 5 that radiates heat absorbed by the heat receiving portion 4, and a working fluid (12 in FIG. 2) serving as a heat medium between the heat receiving portion 4 and the heat radiating portion 5. For example, by providing the heat radiation path 6 for circulating water) and the return path 7, a circulation path that circulates with the heat receiving part 4, the heat radiation path 6, the heat radiation part 5, the return path 7, and the heat receiving part 4 is configured.

  That is, in this circulation path, the working fluid (12 in FIG. 2) is a gas (water vapor in the case of water) or a liquid and a mixed state thereof, the heat receiving part 4, the heat radiation path 6, the heat radiation part 5, the return path 7, It circulates in one direction with the heat receiving part 4.

  Further, as shown in FIG. 2, the heat receiving portion 4 is in contact with the semiconductor switching element 10 to absorb heat and a heat receiving space that covers the surface of the heat receiving plate 11 and evaporates the flowing working fluid 12. And a heat-receiving plate cover 14 that forms 13.

  Furthermore, the heat receiving plate cover 14 is provided with an inlet 15 for flowing the liquefied working fluid 12 into the heat receiving space 13 and an outlet 16 for discharging the working fluid 12 from the heat receiving space 13 as a gas. That is, the inlet 15 and the outlet 16 are provided on the upper surface or the side surface of the heat receiving plate cover 14, the return path 7 is connected to the inlet 15, and the heat dissipation path 6 is connected to the outlet 16. .

  Further, an inflow pipe 19 that supplies the working fluid 12 into the heat receiving portion 4 is connected to the heat receiving portion 4 side of the return path 7 in a state of protruding into the heat receiving space 13. The inflow pipe 19 may be an extension of the return path 7 in which the return path 7 is plunged into the heat receiving portion 4, or an inflow pipe 19 that is a member different from the return path 7 is connected to the return path 7. It may be. Further, a check valve 18 is provided at the inlet 15 of the heat receiving part 4 and the connecting part of the inflow pipe 19. The check valve 18 may be provided in the return path 7 or the inflow pipe 19 as long as it is in the vicinity of the heat receiving portion 4.

  As shown in FIG. 3A, the heat dissipating part 5 includes a hairpin tube 21 having heat dissipating fins 20 for releasing heat to the outside air. For example, the heat dissipating fins 20 formed of aluminum in a thin strip shape have a predetermined interval. Are stacked. Then, heat is radiated by blowing outside air from the blower 9 to the surface of the radiating fin 20. The heat radiation from the surface of the heat radiation fin 20 can also be utilized for heating in the electric vehicle 1. Moreover, the heat radiating part 5 cut | disconnects the slight connection part of each notch part provided in the radiation fin 20 of Fig.3 (a), and as shown in FIG.3 (b), two straight pipes are V-shaped direction. (The both ends of the hairpin tube 21 are expanded vertically). That is, the heat radiating section 5 is installed so that the working fluid flow path has a downward slope by connecting the upper end to the heat radiating path 6 and the lower end to the return path 7. Further, the shielding body 28 is formed in the gap of the radiating fin 20 facing the curved portion of the hairpin tube 21, that is, the gap seen from the horizontal direction between the lower end of the radiating fin 20 and the upper end of the radiating fin 20 disposed below. By adopting the inserted configuration, the gap between the lower end of the upper radiating fin 20 and the upper end of the lower radiating fin 20 in the portion through which the cooling air passes is reduced, so that the cooling air is reduced to a gap with less pressure loss. There is no uneven flow, and the heat radiation fins 20 can be efficiently passed. When the cooling air flows into the gaps between the radiating fins 20, the cooling air passes through the radiating unit 5 without receiving heat from the radiating fins 20, so that the cooling efficiency is lowered. By preventing air from flowing into the gaps between the radiating fins 20, it is possible to prevent a decrease in cooling efficiency. As a result, cooling of the semiconductor switching element 10 that is a heating element is continuously and stably repeated, so that the cooling device 3 can cool the heating element without deteriorating the cooling performance.

  Further, the shield 28 may have a protruding portion 30 that protrudes in the inflow direction of the cooling air that cools the heat radiating portion 5. With this configuration, the cooling air toward the shield 28 can smoothly flow between the heat radiating fins 20 along the protrusion 30 of the shield 28. Therefore, the cooling air can efficiently pass between the radiation fins 20. Therefore, the pressure loss due to the movement of the cooling air does not increase, and the efficiency of cooling the radiating fin 20 does not decrease. As a result, the cooling of the heating element is repeated continuously and the cooling performance is lowered. Therefore, it is possible to provide the cooling device 3 that can cool the heating element.

  The shield 28 may have another protrusion 30 that protrudes in the direction opposite to the direction in which the protrusion 30 protrudes. With this configuration, even if the cooling air is sucked in from which of the heat radiation fins 20 with the shield 28 inserted, that is, even when the direction in which the cooling air flows is reversed, the cooling air is not protruded from the shield 28. 30 can smoothly flow between the radiating fins 20. Therefore, the cooling air can efficiently pass between the radiation fins 20. Therefore, the pressure loss due to the movement of the cooling air does not increase, and the efficiency of cooling the radiating fin 20 does not decrease. As a result, the cooling of the heating element is repeated continuously and the cooling performance is lowered. Therefore, it is possible to provide the cooling device 3 that can cool the heating element.

  The operation of the cooling device 3 having such a configuration will be described.

  In the above configuration, when the semiconductor switching element 10 of the inverter circuit 2 starts to operate, electric power is supplied to the electric motor, and the electric vehicle 1 starts to move. At this time, a large current flows through the semiconductor switching element 10, and at least several percent of the total power is lost to generate a large amount of heat. On the other hand, the heat generated from the semiconductor switching element 10 is removed by the latent heat generated when the working fluid 12 supplied onto the heat receiving plate 11 of the heat receiving space 13 is instantly vaporized. The heat flows from the discharge port 16 to the heat radiation path 6, and heat is released from the heat radiation fins 20 to the outside air due to condensation in the heat radiation unit 5 to be liquefied. The working fluid 12 liquefied in the heat radiating section 5 flows to the return path 7 and accumulates on the check valve 18 at the inlet 15. The liquefied working fluid 12 gradually increases in the return path 7, while the pressure in the heat receiving space 13 decreases conversely as the working fluid 12 is vaporized. When the pressure in the heat receiving space 13 becomes smaller than the water head pressure of the working fluid 12 accumulated on the check valve 18, the check valve 18 is pushed and operates again on the heat receiving plate 11 in the heat receiving space 13. Fluid 12 is supplied. In this way, the working fluid 12 circulates in the cooling device 3 to cool the semiconductor switching element 10.

  Here, the cooling mechanism in the heat receiving space 13 will be described.

  In the heat receiving space 13, the working fluid 12 from the return path 7 is dropped as droplets from the inflow pipe 19 onto the heat receiving plate 11. The dropped working fluid 12 is diffused from the gap between the end opening of the inflow pipe 19 and the heat receiving plate 11 to the outer peripheral portion. At this time, the surface of the heat receiving plate 11 has a shape in which the flow path radially expands, and the working fluid 12 spreads on the heat receiving plate 11 as a thin liquid film. Since the back surface side of the heat receiving plate 11 is in contact with the semiconductor switching element 10, the working fluid 12 that has become a thin liquid film is vaporized in an instant.

  For example, when the working fluid 12 is water and the atmospheric pressure in the circulation path including the heat receiving space 13 is set lower than the atmospheric pressure, the vapor can be vaporized at a temperature lower than the boiling of water in the atmospheric pressure.

  As in this embodiment, by setting the atmospheric pressure to -97 kPa and keeping the inside of the circulation path saturated, the boiling temperature according to the outside air temperature is determined and water can be easily vaporized. The semiconductor switching element 10 can be deprived of heat and cooled.

  Further, when the working fluid 12 is vaporized, the pressure in the heat receiving space 13 increases. However, the working fluid 12 does not flow back to the return path 7 due to the action of the check valve 18, and the discharge port 16 is surely provided. To the heat dissipation path 6. By operating the cooling device 3 in this manner, a regular heat receiving and releasing cycle can be performed, and the working fluid 12 can be continuously vaporized in the heat receiving space 13 to cool the semiconductor switching element 10. A large cooling effect can be obtained.

  Normally, the working fluid 12 flows into the hairpin tube 21 in a mixed state of the gas phase and the liquid phase in the heat radiating unit 5, and is completely liquefied immediately before the lowermost end of the hairpin tube 21, that is, immediately before the connection part with the return path 7. It flows to the return path 7 and accumulates on the check valve 18 at the inlet 15.

  As described above, as shown in FIG. 3B, the heat dissipating unit 5 connects the upper end to the heat dissipating path 6 and the lower end to the return path 7 so that the working fluid 12 in the hairpin tube 21 has a flow path. It is installed so as to have a downward slope. The reason for the downward slope is that when the hairpin tube 21 is horizontal, the liquefied working fluid 12 stays in the hairpin tube 21 (particularly, in the case of water, it tends to adhere to the inner wall of the tube), This is because there is a possibility that it will not flow, and when the outside air temperature is low, liquefaction is promoted and stagnation is likely to occur on the upper end side of the hairpin tube 21, and this configuration is particularly effective. Further, the downward gradient is from top to bottom, and the gradient, that is, the inclination angle, is configured to satisfy θ1 <θ2 <θ3. In order to make it difficult for the liquefied working fluid 12 to stay in the hairpin tube 21, the inclination angle may be constant and large. However, as is apparent from FIGS. 3 (a) and 3 (b), the size of the cooling device 3 is increased. In consideration of this, since it is preferable that the gradient is not small, it is preferable that the working fluid 12 is in a gas-liquid mixed state and the amount of gas in the upper hairpin tube 21 is large. This is effective in reducing the size of the cooling device 3. On the other hand, the flow of the working fluid 12 in the hairpin tube 21 on the lower end side where the amount of gas is small is greatly influenced by gravity, and it is necessary to increase the inclination angle, so that the influence of gravity increases as it goes from top to bottom. As can be seen, the inclination angle is also increased in order.

  Next, the heat dissipating part shown in FIG. 3B can be easily manufactured as follows.

  As shown in FIG. 3A, the heat dissipating fin 20 is provided with a plurality of through-holes 23 through which the hairpin tube 21 is penetrated, for example, in a long and narrow aluminum plate, and the through-hole 23 and the adjacent through-hole 23 A notch 24 that is elongated in the lateral direction is provided at the center in the lateral direction of the plate. The hairpin tube 21 is composed of a straight tube and a curved tube, and a plurality of plates are arranged so that the through-holes 23 are connected at a predetermined interval, and the straight tubes are respectively passed through the connected through-holes 23. The end of the straight pipe adjacent to the pipe is connected to both ends of the curved pipe, the connecting portions 27 of the plurality of plate bodies are separated by, for example, a disk cutter, and the two straight pipes are expanded in the V-shaped direction to thereby dissipate the radiating fins 20. Form and manufacture. Further, the shield 28 formed in advance is inserted into a space viewed from the horizontal direction between the lower end of the heat radiating fin 20 and the upper end of the heat radiating fin 20 disposed below. FIG. 4 is a view showing how the cooling air 29 passes between the shield 28 and the heat radiating fins 20. When the cooling air 29 flows into the space between the radiating fins 20, it collides with the shield 28, but moves along the wedge-shaped portion of the shield 28 and can pass between the radiating fins 20. Further, the shield 28 may have a shape combining wedge shapes as shown in FIG. With this configuration, the same effect can be obtained even if the inflow direction of the cooling air 29 is switched.

  As described above, the installation of the working fluid 12 in the hairpin tube 21 of the heat radiating unit 5 so as to have a downward slope can suppress the retention of the working fluid 12 in the hairpin tube 21. Can be continuously circulated through the cooling device 3, and the semiconductor switching element 10 can be cooled stably and continuously. Furthermore, since the amount of the working fluid 12 staying in the heat radiating section 5 can be reduced, the amount of the working fluid 12 initially sealed in the cooling device 3 can be reduced, and when a storage tank or the like is provided, this storage tank A capacity | capacitance can also be made small and the effect of size reduction and weight reduction of the cooling device 3 can be created. Furthermore, the manufacture of the heat radiating part 5 having the downward gradient of the flow path is still simple, by cutting the slight connecting part 27 between the notches 24 of the heat radiating fin 20 and expanding the two straight pipes in the V-shape. By inserting a shield with a structure, it can be easily manufactured, and the efficiency of cooling the radiating fins will not decrease. As a result, the cooling of the heating element is repeated continuously and stably, without reducing the cooling performance. In addition, a cooling device that can cool the heating element can be provided.

  In the above embodiment, the cooling device 3 is applied to the electric vehicle 1. However, the cooling device 3 can also be applied to a hybrid vehicle using both electricity and gasoline, and the inverter circuit 2 that is a power converter is an electronic device. However, the cooling device 3 can also be applied to electronic equipment.

  The cooling device according to the present invention has a circulation path of the working fluid as one direction by setting a circulation path of the working fluid serving as a refrigerant as a heat receiving section, a heat radiation path, a heat radiation section, a return path, and the heat receiving section. An inflow pipe that supplies the working fluid into the heat receiving part is connected to the heat receiving part side of the return path, and a check valve is provided at a connection part between the heat receiving part and the inflow pipe, so that the working fluid is supplied in the heat receiving part. It is possible to rapidly vaporize and move the working fluid vigorously in the heat receiving plate portion. As a result, the heat transfer efficiency on the heat transfer surface can be increased and the cooling effect can be increased.

  Further, in the present invention, the flow path of the working fluid in the heat radiating portion is configured to have a downward slope, and the heat radiating portion is configured by a hairpin tube having a heat radiating fin, By adopting a configuration in which the shield is inserted into the space viewed from the horizontal direction between the lower end and the upper end of the heat dissipating fins disposed below, the cooling efficiency of the heat dissipating fins does not decrease.

  For this reason, it is useful for cooling power semiconductors used in power conversion devices as drive devices for electric vehicles, CPUs with high heat generation, and the like.

DESCRIPTION OF SYMBOLS 1 Electric vehicle 2 Inverter circuit 3 Cooling device 4 Heat receiving part 5 Heat radiating part 6 Heat radiating path 7 Return path 9 Blower 10 Semiconductor switching element 11 Heat receiving plate 12 Working fluid 13 Heat receiving space 14 Heat receiving plate cover 15 Inlet 16 Outlet 18 Check valve DESCRIPTION OF SYMBOLS 19 Inflow pipe 20 Radiation fin 21 Hairpin pipe 23 Through-hole 24 Notch part 27 Connection part 28 Shielding body 29 Cooling air 30 Protrusion part

Claims (5)

A heat receiving section having a heat receiving plate for transferring heat from the heating element to the working fluid;
A heat dissipating part for releasing the heat of the working fluid;
A heat dissipation path and a return path that connect the heat receiving section and the heat dissipation section;
A cooling device that circulates the working fluid to the heat receiving portion, the heat radiating path, the heat radiating portion, the return path, and the heat receiving portion to move heat;
An inflow pipe projecting into the heat receiving portion from a connection portion between the return path and the heat receiving portion;
Provide a check valve in the return path or the inflow pipe,
The heat dissipating part includes a hairpin tube having a plurality of heat dissipating fins,
The hairpin tube is configured so that the flow path of the working fluid has a downward slope,
A cooling device, characterized in that a shielding body is inserted into the gap of the heat radiating fin facing the curved portion of the hairpin tube. The cooling device according to claim 1, wherein the shield has a protruding portion that protrudes in an inflow direction of cooling air that cools the heat radiating portion. The cooling device according to claim 2, wherein the shielding body has another protrusion that protrudes in a direction opposite to a direction in which the protrusion protrudes. An electronic apparatus comprising the cooling device according to claim 1. An electric vehicle comprising the cooling device according to any one of claims 1 to 3.