Surge tank

Abstract

To provide a surge tank capable of reducing a change of a temperature of temperature control liquid circulating in a vehicle component due to heat exchange between the temperature control liquid and the atmosphere.SOLUTION: A surge tank provided in a flow passage in which temperature control liquid for controlling a temperature of a vehicle component circulates includes: a first tank; a second tank provided within the first tank; an introduction port for introducing the temperature control liquid in the flow passage to the second tank; a derivation port for deriving the temperature control liquid in the second tank to the flow passage; and a communication part that is provided in the second tank and enables flowing of the temperature control liquid between a space between the first tank and the second tank and inside of the second tank.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a surge tank. [Background technology]

[0002] Vehicles such as electric vehicles and engine vehicles include various components such as drive components. For example, if the temperature of the components included in an electric vehicle is excessively low or high, the performance, operation, etc. may be adversely affected. For this reason, various vehicles including electric vehicles may be equipped with a temperature control system that controls the temperature of the components by circulating a liquid.

[0003] In addition, since liquids can expand due to temperature, surge tanks are provided to prevent damage to pipes, components, etc. due to pressure caused by the expansion of the liquid. Patent Document 1 discloses a surge tank used in an engine cooling circuit. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2022-152514 A Summary of the Invention [Problem to be solved by the invention]

[0005] In a temperature control system such as that disclosed in Patent Document 1, when liquid circulates between the surge tank and the component to be temperature controlled, heat exchange occurs in the surge tank between the liquid in the surge tank and the atmosphere outside the surge tank. When used in an engine cooling circuit, the engine is hot, so the impact of heat exchange between the liquid in the surge tank and the atmosphere is thought to be small.

[0006] Incidentally, for example, the temperature of a component that is a temperature control target of an electric vehicle may change in the same manner as the temperature of the atmosphere. Specifically, when the temperature of the atmosphere decreases, the temperature of the component that is a temperature control target also decreases, and when the temperature of the atmosphere increases, the temperature of the component that is a temperature control target also increases.

[0007] For example, when the atmospheric temperature and the temperature of a component to be temperature-controlled are excessively low and the component needs to be heated, the liquid is heated using heat generated by a heater, and the liquid is circulated between the surge tank and the component.

[0008] On the other hand, in such a case, the heat of the liquid circulating between the surge tank and the component to be temperature controlled may be lost to the atmosphere outside the surge tank through heat exchange in the surge tank, resulting in a drop in the temperature of the liquid.

[0009] Also, for example, when the atmospheric temperature and the temperature of a component to be temperature-controlled are excessively high and the component needs to be cooled, a fan, a radiator, etc. are used to cool the liquid while circulating the liquid between the surge tank and the component.

[0010] On the other hand, in such a case, the liquid circulating between the surge tank and the component to be temperature controlled may absorb heat from the atmosphere outside the surge tank through heat exchange in the surge tank, resulting in an increase in the temperature of the liquid.

[0011] Therefore, if heat exchange between the liquid in the surge tank and the atmosphere is easy as in Patent Document 1, the liquid is easily affected by the atmosphere. As a result, for example, components that are not hot and are subject to temperature control in an electric vehicle, such as the engine, may be significantly affected by the atmosphere, and the efficiency of temperature control may decrease. Therefore, for example, in an electric vehicle, if power is supplied to a heater or a fan from the drive battery, the electric fuel efficiency may worsen.

[0012] The present invention has been made in consideration of the above-mentioned situation, and has an object to provide a surge tank that can reduce changes in temperature of a temperature-control fluid caused by heat exchange between the temperature-control fluid circulating through vehicle components and the atmosphere. [Means for solving the problem]

[0013] The present invention has been made to solve at least some of the problems described above, and can be realized in the following aspects or application examples.

[0014] The surge tank of this application example is a surge tank provided in a flow path through which a temperature regulating liquid for regulating the temperature of vehicle components circulates, and includes a first tank, a second tank provided within the first tank, an inlet for introducing the temperature regulating liquid from the flow path into the second tank, an outlet for discharging the temperature regulating liquid from the second tank to the flow path, and a communication portion provided in the second tank to enable the temperature regulating liquid to flow between a space between the first tank and the second tank and the inside of the second tank.

[0015] According to this application example, the temperature control liquid is retained between the first tank and the second tank, and the temperature control liquid reduces heat exchange between the temperature control liquid in the second tank and the atmosphere outside the surge tank. That is, the temperature of the temperature control liquid in the second tank is maintained to a certain degree by the temperature control liquid between the first tank and the second tank. In other words, the temperature control liquid between the first tank and the second tank reduces temperature changes in the temperature control liquid in the second tank. In addition, because of these factors, when controlling the temperature of components of an electric vehicle, for example, the temperature of the components of the electric vehicle can be efficiently controlled to a temperature at which the performance, operation, etc. of the components are stabilized, by circulating the temperature control liquid while separating air bubbles in the temperature control liquid from the temperature control liquid in the surge tank. [Brief description of the drawings]

[0016] [Figure 1] 1 is a schematic diagram showing a portion of an example of the configuration of a temperature adjustment system according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a side end view showing an example of the configuration of the surge tank of the present embodiment. [Diagram 3]FIG. 3 is an AA end view of the surge tank shown in FIG. 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] 1. Temperature control system configuration First, a temperature adjustment system 10 of the present embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic diagram showing a portion of an example of the configuration of the temperature adjustment system 10 of the present embodiment.

[0018] The temperature adjustment system 10 is a system provided in an electric vehicle (not shown) and adjusts the temperature of a target component among the components provided in the electric vehicle. Hereinafter, the target component of the temperature adjustment may be simply referred to as a "temperature adjustment target part."

[0019] An electric vehicle is a vehicle that uses at least a power source as a power source. Examples of electric vehicles (xEVs) include hybrid electric vehicles (HEVs), electric vehicles (EVs), plug-in hybrid vehicles (PHVs), and fuel cell vehicles (FCVs, or Fuel Cell Electric Vehicles).

[0020] The temperature adjustment system 10 includes a temperature adjustment liquid 20 (see FIG. 2), a circulation flow path 30, one or more temperature adjustment target parts 40, a flow path switching part 50, and a surge tank 60. Although not shown in the figures, the temperature adjustment system 10 may also include a radiator, a fan that blows air to the radiator, a heater for heating the temperature adjustment liquid 20, and the like.

[0021] The temperature adjustment liquid 20 is a liquid for adjusting the temperature of the temperature adjustment target portion 40. As the temperature adjustment liquid 20, for example, water is used.

[0022] The circulation flow path 30 is a flow path through which the temperature adjustment liquid 20 circulates. The circulation flow path 30 includes a plurality of pipes 32 that form a flow path for the temperature adjustment liquid 20. Ends of the pipes 32 are connected to the temperature adjustment target portion 40, the surge tank 60, an intermediate position of another pipe 32, a flow path switching unit 50, or the like. In FIG. 1, the end of the pipe 32 is connected to any one of the temperature adjustment target portion 40, the surge tank 60, an intermediate position of another pipe 32, and the flow path switching unit 50.

[0023] As described above, the temperature adjustment target portion 40 is a component that is a target for temperature adjustment among the components provided in the electric vehicle.

[0024] The temperature adjustment target unit 40 is, for example, a component that operates in conjunction with the driving of the electric vehicle, and whose temperature itself affects the performance, operation, and the like.

[0025] A battery, which is a specific example of the temperature adjustment target 40, has an adverse effect on performance, operation, etc. if its temperature is excessively high or low. Other examples of the temperature adjustment target 40 include a motor generator, an inverter, a pump, and a fan, in addition to a battery.

[0026] The flow path switching unit 50 is provided at the end of the circulation flow path 30, specifically, the tube 32, and switches the flow path of the temperature regulating liquid 20. For example, an electrically controllable valve is used as the flow path switching unit 50. Also, for example, a thermostat that switches between an open state and a closed state depending on the temperature of the temperature regulating liquid 20 may be used as the flow path switching unit 50.

[0027] The surge tank 60 is a tank capable of containing the temperature adjustment liquid 20, and separates air bubbles generated within the temperature adjustment liquid 20. The surge tank 60 is provided on the circulation flow path 30, specifically, on the end of the tube 32. The surge tank 60 is formed, for example, from a resin member.

[0028] In such a temperature adjustment system 10, the temperature of the temperature adjustment target portion 40 can be adjusted by circulating the temperature adjustment liquid 20 through the circulation flow path 30. For example, when the temperature of the temperature adjustment target portion 40 is lower than that of the temperature adjustment liquid 20, the temperature adjustment target portion 40 can be heated by circulating the temperature adjustment liquid 20. Also, when the temperature of the temperature adjustment target portion 40 is higher than that of the temperature adjustment liquid 20, the temperature adjustment target portion 40 can be cooled by circulating the temperature adjustment liquid 20.

[0029] 2. Configuration of surge tank Next, the surge tank 60 of this embodiment will be described with reference to Fig. 2 and Fig. 3. Fig. 2 is a side end view of an example of the configuration of the surge tank 60 of this embodiment. Fig. 3 is an AA end view of the surge tank 60 shown in Fig. 2.

[0030] Specifically, the surge tank 60 is a tank with a double structure capable of containing the temperature regulating liquid 20, and includes a first tank 70 and a second tank 90. ​​Among the pipes 32 connected to the surge tank 60, the pipe 32 that introduces the temperature regulating liquid 20 into the surge tank 60 is an inlet pipe 32i. Among the pipes 32 connected to the surge tank 60, the pipe 32 that discharges the temperature regulating liquid 20 from the surge tank 60 is an outlet pipe 32o.

[0031] The first tank 70 is a tank capable of containing the temperature regulating liquid 20. The first tank 70 includes an opening 72, a pressure cap 74, a first insertion portion 76, and a second insertion portion 78. The first tank 70 has, for example, a hollow, substantially rectangular parallelepiped shape.

[0032] The opening 72 is a vent hole, and is provided at a position higher than the water surface position of the temperature regulating fluid 20 in the surge tank 60. In the example shown in FIG.

[0033] The water surface position of the temperature regulating liquid 20 is, for example, the water surface position of the temperature regulating liquid 20 when the temperature regulating liquid 20 is circulating through the circulation flow path 30 as shown in Fig. 2. The water surface position of the temperature regulating liquid 20 is determined based on, for example, the amount of the temperature regulating liquid 20, the volume of the circulation flow path 30, the volume of the surge tank 60, the amount of the temperature regulating liquid 20 introduced into the surge tank 60 per hour, and the amount of the temperature regulating liquid 20 discharged from the surge tank 60 per hour.

[0034] In addition, a pressure cap 74 is attached to the opening 72. The pressure cap 74 includes a pressure valve (not shown) and a vacuum valve (not shown).

[0035] The pressure valve opens when the pressure in the surge tank 60 reaches or exceeds a specified value. On the other hand, the vacuum valve opens when the pressure in the surge tank 60 becomes negative. As a result, the pressure cap 74 maintains the pressure in the circulation flow path 30 at a specified value.

[0036] The first insertion portion 76 is an insertion port through which the introduction pipe 32i extending to the second tank 90 is inserted. In the example shown in Fig. 2 and Fig. 3, the first insertion portion 76 is provided on the side wall 70b of the first tank 70. The first insertion portion 76 is also subjected to a leak-proof treatment to prevent the temperature regulating liquid 20 from leaking from the first tank 70 to the outside of the surge tank 60.

[0037] The second insertion portion 78 is an insertion port through which the outlet pipe 32o extending to the second tank 90 is inserted. In the example shown in Fig. 2 and Fig. 3, the second insertion portion 78 is provided on the side wall 70b of the first tank 70. The second insertion portion 78 is also subjected to a leak-proof treatment to prevent the temperature regulating liquid 20 from leaking from the first tank 70.

[0038] The second tank 90, like the first tank 70, is a tank capable of containing the temperature regulating liquid 20, and is disposed within the first tank 70. The second tank 90 can also be said to be the innermost tank in the surge tank 60.

[0039] Furthermore, since the second tank 90 is disposed inside the first tank 70, the volume of the second tank 90 is smaller than the volume of the first tank 70. As a result, the wall forming the first tank 70 serves as the outer wall of the surge tank 60, and the wall forming the second tank 90 serves as the inner wall of the surge tank 60.

[0040] Furthermore, for these reasons, a space D is provided between the wall forming the first tank 70 and the wall forming the second tank 90.

[0041] 2 and 3, the ceiling wall 90a of the second tank 90 faces, with a gap between it and the ceiling wall 70a of the first tank 70 within the first tank 70. Furthermore, the side wall 90b of the second tank 90 faces, with a gap between it and the side wall 70b of the first tank 70 within the first tank 70. Furthermore, the bottom wall 90c of the second tank 90 faces, with a gap between it and the bottom wall 70c of the first tank 70 within the first tank 70.

[0042] The end of the side wall 90b of the second tank 90 on the side of the ceiling wall 90a is located higher than the water surface position of the temperature regulating liquid 20.

[0043] The second tank 90 includes an opening 92, an inlet 94, an outlet 96, a communication part 98, and the like. The opening 92 is a vent hole, similar to the opening 72 of the first tank 70. The opening 92 is provided at a position higher than the water surface position of the temperature regulating liquid 20. In the example shown in FIGS. 2 and 3, the opening 92 is provided in the ceiling wall 90a of the second tank 90.

[0044] The introduction part 94 is an inlet for the temperature regulating liquid 20. In the example shown in FIGS. 2 and 3, the introduction part 94 is provided on a side wall 90b of the second tank 90. ​​The introduction part 94 is connected to the introduction pipe 32i. Therefore, the introduction pipe 32i specifically introduces the temperature regulating liquid 20 into the second tank 90 of the surge tank 60.

[0045] Moreover, the introduction section 94 is provided at a position lower than the water surface position of the temperature regulating liquid 20. The air bubbles in the temperature regulating liquid 20 rise toward the water surface position of the temperature regulating liquid 20, and when they reach the water surface position, the air bubbles are separated from the temperature regulating liquid 20.

[0046] Therefore, the closer the position of the inlet part 94 is to the surface level of the temperature regulating liquid 20, the faster the air bubbles can be separated from the temperature regulating liquid 20. In other words, the closer the position of the inlet part 94 is to the surface level of the temperature regulating liquid 20, the lower the possibility that air bubbles will be contained in the temperature regulating liquid 20 discharged from the discharge part 96.

[0047] For these reasons, it is preferable that the introduction section 94 be provided at a position lower than the level of the surface of the temperature adjustment liquid 20 and close to that level.

[0048] The outlet portion 96 is an outlet for the temperature regulating liquid 20. In the example shown in Fig. 2 and Fig. 3, the outlet portion 96 is provided on a side wall 90b of the second tank 90. ​​The outlet portion 96 is connected to the outlet pipe 32o. Specifically, the outlet pipe 32o therefore leads out the temperature regulating liquid 20 in the second tank 90 of the surge tank 60 from the surge tank 60.

[0049] Moreover, the outlet portion 96 is provided at a position lower than the surface position of the temperature regulating liquid 20. The air bubbles in the temperature regulating liquid 20 rise toward the surface position of the temperature regulating liquid 20, as described above.

[0050] Therefore, the further the position of the outlet portion 96 is from the surface position of the temperature regulating liquid 20, the lower the possibility that air bubbles will be contained in the temperature regulating liquid 20 that is discharged from the outlet portion 96.

[0051] For these reasons, it is preferable that the outlet portion 96 is provided at a position lower than the level of the temperature adjustment liquid 20 and far from the level of the liquid surface.

[0052] Furthermore, as described above, air bubbles in the temperature-regulating liquid 20 rise toward the water surface position of the temperature-regulating liquid 20, so if the position of the outlet portion 96 is lower than the position of the inlet portion 94, the possibility of air bubbles being contained in the temperature-regulating liquid 20 discharged from the surge tank 60 is reduced.

[0053] For these reasons, it is preferable that the outlet portion 96 be provided at a position lower than the surface position of the temperature adjustment liquid 20 and lower than the inlet portion 94.

[0054] In addition, in such a surge tank 60, the temperature regulating liquid 20 flows from the inlet portion 94 toward the outlet portion 96. Therefore, the greater the distance between the inlet portion 94 and the outlet portion 96, the longer it takes for the temperature regulating liquid 20 to reach the outlet portion 96 from the inlet portion 94.

[0055] For this reason, the greater the separation between the inlet portion 94 and the outlet portion 96, the more air bubbles can be separated from the temperature regulating liquid 20. In other words, the greater the separation between the inlet portion 94 and the outlet portion 96, the less likely air bubbles will be contained in the temperature regulating liquid 20 that is discharged from the surge tank 60 to the outlet pipe 32o.

[0056] For these reasons, it is preferable that the inlet portion 94 and the outlet portion 96 are spaced apart as far as possible.

[0057] The communication part 98 is a communication port, and connects the interior of the second tank 90 with the space D. The communication part 98 is provided at a position lower than the water surface position of the temperature adjustment liquid 20. In the example shown in FIG. 2, the communication part 98 is provided in the side wall 90b of the second tank 90 at a position lower than the outlet part 96. The surge tank 60 of this embodiment has one communication part 98.

[0058] The size of the communication opening corresponding to the communication portion 98 is set to a size that allows the second tank 90 to maintain its role as the inner wall of the surge tank 60. Therefore, the communication portion 98 can also be called, for example, a slit or a gap.

[0059] The communication part 98 allows the temperature regulating liquid 20 to move to the space D via the second tank 90, and the temperature regulating liquid 20 to be stored in the space D. The communication part 98 also allows the temperature regulating liquid 20 to move from the space D into the second tank 90. ​​In other words, the communication part 98 allows the temperature regulating liquid 20 to flow between the second tank 90 and the space D.

[0060] In addition, with regard to the surge tank 60 of this embodiment, the air pressure acting on space D and the air pressure acting inside the second tank 90 are made the same, and the water surface position of the temperature regulating liquid 20 stored in space D and the water surface position of the temperature regulating liquid 20 stored in the second tank 90 are aligned, so that the space at a position higher than the water surface position of the temperature regulating liquid 20 is made into an integrated space.

[0061] In the surge tank 60 of this embodiment, the temperature regulating liquid 20 that is retained in the space D exists between the temperature regulating liquid 20 in the second tank 90 and the atmosphere outside the surge tank 60. The space D is connected to the inside of the second tank 90 via a communication part 98 that serves both to introduce the temperature regulating liquid 20 and to discharge the temperature regulating liquid 20, so that the fluidity of the temperature regulating liquid 20 is low between the space D and the second tank 90. ​​In this case, even if the temperature of the temperature regulating liquid 20 in the space D becomes higher or lower than that of the temperature regulating liquid 20 in the second tank 90 due to the atmosphere outside the surge tank 60, the temperature regulating liquid 20 in the space D is unlikely to mix with the temperature regulating liquid 20 in the second tank 90. ​​Therefore, the temperature regulating liquid 20 retained in the space D functions as a heat insulating material, and the heat exchange between the atmosphere outside the surge tank 60 and the temperature regulating liquid 20 in the second tank 90 is reduced by the temperature regulating liquid 20 in the space D. That is, according to the surge tank 60 of this embodiment, the temperature of the temperature regulating liquid 20 in the second tank 90 is maintained to a certain degree by the temperature regulating liquid 20 retained in the space D between the first tank 70 and the second tank 90. ​​In other words, the temperature change of the temperature regulating liquid 20 in the second tank 90 is reduced by the temperature regulating liquid 20 retained in the space D between the first tank 70 and the second tank 90.

[0062] Furthermore, for this reason, when controlling the temperature of the temperature-control target portion 40, the temperature can be efficiently controlled to a temperature at which the performance, operation, etc. of the temperature-control target portion 40 is stabilized by separating the air bubbles in the temperature-control liquid 20 from the temperature-control liquid 20 in the surge tank 60 while circulating the temperature-control liquid 20 in the circulation flow path 30.

[0063] For example, when the atmospheric temperature and the temperature of the temperature control target part 40 are excessively low and the temperature control target part 40 needs to be heated, and the temperature control liquid 20 circulates between the surge tank 60 and the temperature control target part 40, the temperature of the temperature control liquid 20 gradually rises together with the temperature control target part 40. In such a case, the temperature control liquid 20 in the space D of the surge tank 60 reduces the amount of heat of the temperature control liquid 20 in the second tank 90 that is taken away by the atmosphere outside the surge tank 60. Also, for this reason, when the temperature control target part 40 is heated, the temperature control target part 40 can be efficiently heated to a temperature at which the performance, operation, etc. of the temperature control target part 40 are stable.

[0064] Furthermore, for example, when the atmospheric temperature and the temperature of the temperature control target part 40 are excessively high and the temperature control target part 40 needs to be cooled, and the temperature control liquid 20 circulates between the surge tank 60 and the temperature control target part 40, the temperature of the temperature control liquid 20 gradually decreases together with the temperature control target part 40. In such a case, the temperature control liquid 20 in the space D of the surge tank 60 reduces the amount of heat that the temperature control liquid 20 in the second tank 90 takes from the atmosphere outside the surge tank 60. Therefore, when the temperature control target part 40 is cooled, the temperature control target part 40 can be cooled efficiently.

[0065] The specific configuration shown in this embodiment is just one example, and as long as it is possible to maintain the temperature of the temperature control liquid 20 in the second tank 90, the aspects of the present invention are not limited to the configuration shown in this embodiment.

[0066] For example, there is no particular limitation on the configuration of the circulation flow path 30. In addition, for example, with respect to the second tank 90, the ceiling wall 90a may be omitted, and the ceiling side of the second tank 90 may be the opening 92.

[0067] Furthermore, for example, the position of the communication part 98 in the second tank 90 is not particularly limited as long as it is provided at a position lower than the water surface position of the temperature adjustment liquid 20 .

[0068] Furthermore, for example, the number of communication parts 98 is not particularly limited as long as they are provided in the second tank 90 at a position lower than the water surface position of the temperature regulating liquid 20. From the viewpoint of reducing the fluidity of the temperature regulating liquid 20 between the space D and inside the second tank 90, it is preferable that the number of communication parts 98 is small.

[0069] Furthermore, for example, the positions and numbers of the first insertion portion 76 and the second insertion portion 78 in the surge tank 60 are not particularly limited.

[0070] Furthermore, for example, the positions of the inlet portion 94 and the outlet portion 96 in the second tank 90 are not particularly limited as long as they are provided at a position lower than the water surface position of the temperature adjustment liquid 20 .

[0071] Furthermore, for example, as long as the inlet portions 94 and outlet portions 96 are provided at positions lower than the water surface position of the temperature adjustment liquid 20, the number of these is not particularly limited.

[0072] Furthermore, for example, if a space D is provided between a wall forming the first tank 70 and a wall forming the second tank 90, a part of the wall forming the second tank 90 may be omitted, and the wall of the first tank 70 facing the omitted wall may be shared by the first tank 70 and the second tank 90. ​​That is, in this case, the wall of the first tank 70 shared by the first tank 70 and the second tank 90 also serves as the wall of the second tank 90. ​​As a specific example, when the bottom wall 90c of the second tank 90 is omitted, the bottom wall 70c of the first tank 70 is shared by the first tank 70 and the second tank 90, and also serves as the bottom wall 90c of the second tank 90.

[0073] Furthermore, for example, the second tank 90 may be formed of a heat insulating material, or a heat insulating paint may be applied to the second tank 90. ​​In such a case, the heat exchange between the atmosphere outside the surge tank 60 and the temperature adjustment liquid 20 in the second tank 90 can be further reduced.

[0074] Also, for example, the surge tank 60 may be a tank with a triple or more layer structure. In this case, the second tank 90 is disposed in the first tank 70 via another tank, and the other tank has an opening that functions similarly to the communication part 98. In such a case, the heat exchange between the atmosphere outside the surge tank 60 and the temperature regulating liquid 20 in the second tank 90 can be further reduced.

[0075] In addition, although the present embodiment has been described using an electric vehicle, the surge tank 60 may be a surge tank for a vehicle other than an electric vehicle. For example, the present invention can also be applied to a case where it is desired to reduce the temperature change caused by heat exchange with the atmosphere for the temperature control fluid 20 in the surge tank 60 of an engine vehicle or the like. [Explanation of symbols]

[0076] 10 Temperature Control System 20 Temperature Control Liquid 30 Circulation flow path 40 Temperature controlled part 60 Surge Tank 70 Tank 1 90 Tank 2 94 Introduction 96 Derivation part 98 Communication section

Claims

[Claim 1] A surge tank provided in a flow path through which a temperature control fluid for controlling the temperature of a vehicle component circulates, A first tank; a second tank provided within the first tank; an inlet through which the temperature regulating liquid in the flow path is introduced into the second tank; an outlet through which the temperature control liquid in the second tank is discharged to the flow path; a surge tank provided in the second tank, the surge tank including a space between the first tank and the second tank and a communication portion that allows the temperature regulating liquid to flow between the space and the inside of the second tank.

Images