Patent Description:
A main job of a cooling system of a vehicle is to dissipate heat into the air to prevent parts from overheating, where an expansion tank is an important part in the cooling system of the vehicle. The expansion tank can store a cooling liquid and supplement the cooling liquid to the cooling system in time when the cooling system lacks the cooling liquid.

In the solution of the related art, a cooling system that is provided on an electric vehicle includes an expansion tank, a liquid-air separator, an electronic water pump, a part to be cooled (such as a battery pack, a motor, etc.) and a heat exchanger. The liquid-air separator, the electronic water pump, the part to be cooled and the heat exchanger are connected in turn by pipelines to form a closed-loop circuit. The expansion tank is connected to the liquid-air separator by a pipeline, thereby absorbing the air separated from the liquid-air separator or supplementing a cooling liquid to the liquid-air separator. When in use, the electronic water pump is started to drive the cooling liquid and a gas to flow into the part to be cooled and take heat away, then the cooling liquid enters the heat exchanger for cooling; and the cooling liquid flowing out from the heat exchanger enters the liquid-gas separator for gas-liquid separating, where the gas flows into the expansion tank and the separated cooling liquid flows into the electronic water pump for continuing to perform cooling cycle.

However, when the solution of the related art is used, the number of parts in the cooling system is high and the weight of the parts is heavy, therefore, it is not conducive to lightweight of vehicles.

<CIT> discloses an expansion tank for an engine cooling system, comprising a housing defining an enclosed chamber and having a coolant inlet connection for coolant discharged from the engine, a coolant collector and a coolant outlet connection. The coolant inlet may direct the coolant tangentially towards a wall of the housing to help trapped air and vapour to escape from the coolant. The collector may comprise a gutter arranged on the housing wall below the stream of incoming coolant from the inlet and a funnel may then direct the coolant from the gutter to the outlet. One side of the gutter may have a weir which extends to a height which is less that of the walls of the gutter and the walls of the funnel. At low coolant flow rates all the coolant collected in the gutter flows in to the funnel and is delivered back to the engine without substantial mixing with a mass of coolant in the chamber. At higher coolant flow rates, coolant spills over the weir to mix with the main body of coolant in the chamber. This flow of coolant returns to the engine through the outlet connection by way of an outlet.

<CIT> discloses a vehicle radiator, which can reduce the number of cooling water hoses and achieve space saving around the radiator. SOLUTION: A body part is provided, which is connected to radiator cores and which constitutes a radiator. A suction port and a discharge port for engine cooling water W are provided at a vehicle body rear side of the body part. Inside the body part, an outlet passage for communicating the radiator cores and the discharge port, an upstream side reservoir passage branched from the outlet passage and extending upward, and a reservoir tank part communicated with the reservoir passage are provided. At an upper part of the body part, a radiator cap is provided for releasing a pressure of the upstream side reservoir passage. By a pressure valve of the radiator cap being opened, a lower end part of a downstream side reservoir passage in which the engine cooling water W flows from the upstream side reservoir passage and a bottom part of the reservoir tank part are communicated with each other.

<CIT> discloses a expansion tank for a cooling circuit, having an inlet line (<NUM>) and an outlet line (<NUM>) for a coolant (<NUM>) and having a venting opening (<NUM>') in a housing (<NUM>), the inlet line (<NUM>) being arranged on the outlet side and the outlet line (<NUM>) being arranged on the inlet side closely adjacent to the housing (<NUM>), so that the coolant (<NUM>') supplied by the inlet line (<NUM>) passes almost completely into the outlet line (<NUM>), without mixing with the coolant (<NUM>) in the expansion tank (<NUM>), while gas bubbles (<NUM>) are discharged from the coolant (<NUM>') into the expansion tank (<NUM>), characterized in that the inlet line (<NUM>) has an inlet line cross-section (<NUM>') which is at least twice as large as an outlet line cross-section (<NUM>') of the outlet line (<NUM>).

<CIT> discloses a the tank (<NUM>) having upper inflow connection (<NUM>) and a lower discharge connection (<NUM>) for blow-enriched and bubble-free coolants, and a container partition wall (<NUM>) for forming chambers (<NUM>, <NUM>, <NUM>, <NUM>). The wall has an upper opening for the blow-enriched coolant or as pressure balance and a lower opening for the bubble-free coolant. The connection (<NUM>) is discharged into one of the chambers and the connection (<NUM>) is ended in the other chamber.

In order to overcome the aforesaid defects in the related art, the present application aims to provide an expansion tank, a cooling system, and a vehicle to decrease the number and weight of parts in the cooling system, thereby facilitating the lightweight of the vehicle.

An embodiment of the present application provides an expansion tank including a tank body, a first partition is provided within the tank body, the first partition divides an interior of the tank body into a first chamber and a second chamber, and the first partition is provided with a first through hole, and the first chamber communicates with the second chamber through the first through hole;
the tank body is provided with a pipe communicating with an interior of the tank body, and a side wall of the pipe is provided with a mixed liquid inlet; a second partition is provided within the pipe, one end of the second partition is connected to the side wall of the pipe and the other end of the second partition extends to the mixed liquid inlet so as to form a first channel and a second channel within the pipe; the mixed liquid inlet is simultaneously connected to a side wall of the first channel and a side wall of the second channel; in a direction perpendicular to an axis of the mixed liquid inlet, a first end of the first channel is connected to the first chamber, a second end of the first channel is closed, a first end of the second channel is connected to the second chamber, a second end of the second channel is configured to be connected to connect a water pump.

The expansion tank as described above, optionally, an area of the mixed liquid inlet communicating with the first channel is smaller than an area of the mixed liquid inlet communicating with the second channel.

The expansion tank as described above, optionally, an end cap is provided on the second end of the first channel, and the end cap is fixedly connected to the pipe and the second partition.

The expansion tank as described above, optionally, the pipe is cylindrical or prismatic in shape, an axis of the pipe is perpendicular to an axis of the mixed liquid inlet.

The expansion tank as described above, optionally, the tank body includes a first sub-tank body and a second sub-tank body, the first sub-tank body and the second sub-tank body are welded to form the tank body.

The expansion tank as described above, optionally, the first chamber includes a plurality of first sub-chambers, a third partition is provided between two adjacent first sub-chambers, the third partition is provided with a third through hole; the second chamber includes a plurality of second sub-chambers, a fourth partition is provided between two adjacent second sub-chambers, the fourth partition is provided with a fourth through hole.

The expansion tank as described above, optionally, the first through hole is provided between the first sub-chambers and the second sub-chambers adjacent to the first sub-chambers; or the first through hole is provided between one first sub-chamber of the first sub-chambers and one second sub-chamber of the second sub-chambers adjacent to the one first sub-chamber.

The expansion tank as described above, optionally, a plurality of reinforcing ribs are further provided within the tank body.

Another embodiment of the present application provides a cooling system including a water pump, a part to be cooled, a heat exchanger, and the expansion tank as any one of described above; the water pump, the part to be cooled, the heat exchanger, and the expansion tank are connected in turn by pipelines, where the heat exchanger is connected to the mixed liquid inlet of the expansion tank, the second channel of the expansion tank is connected to the water pump.

A further embodiment of the present application provides a vehicle including the cooling system as described above.

The present application provides an expansion tank, a cooling system, and a vehicle, the expansion tank includes a tank body, a first partition is provided within the tank body, the first partition divides an interior of the tank body into a first chamber and a second chamber, the first partition is provided with a first through hole, and the first chamber communicates with the second chamber through the first through hole; the tank body is provided with a pipe communicating with an interior of the tank body, and a side wall of the pipe is provided with a mixed liquid inlet; a second partition is provided within the pipe, one end of the second partition is connected to the side wall of the pipe and the other end of the second partition extends to the mixed liquid inlet so as to form a first channel and a second channel within the pipe; the mixed liquid inlet is simultaneously connected to a side wall of the first channel and a side wall of the second channel; in a direction perpendicular to an axis of the mixed liquid inlet, a first end of the first channel is connected to the first chamber, a second end of the first channel is closed, a first end of the second channel is connected to the second chamber, a second end of the second channel is configured to be connected to a water pump. When the expansion tank of the present application is in use, a mixed liquid of a cooling liquid and a gas simultaneously flows into the first channel and the second channel through the mixed liquid inlet. The mixed liquid flowing into the second channel flows directly into the water pump; the mixed liquid flowing into the first channel enters the first chamber. The gas and cooling liquid are separated within the first chamber under the action of gravity, the separated gas is stored in the expansion tank, the separated cooling liquid enters the second chamber through the first through hole and flows into the water pump through the second channel, thereby reducing the content of gas in the cooling liquid entering the water pump. The expansion tank of the present application has the function of gas-liquid separation, thus there is no need to provide a special liquid-gas separator in the cooling system, thereby facilitating the reduction of the number and total weight of parts in the cooling system, the reduction of the number of pipelines in the cooling system, and the reduction of the costs, and facilitating the lightweight of the vehicle.

To describe the technical solutions in embodiments of the present application or the related art more clearly, the following briefly introduces the accompanying drawings needed for describing the embodiments or the related art. Apparently, the accompanying drawings in the following description are some embodiments of the present application, and other accompanying drawings can be obtained according to these accompanying drawings without creative work for persons of ordinary skill in the art.

To make the objectives, technical solutions, and advantages of embodiments of the present application clearer, the following clearly and comprehensively describes the technical solutions in embodiments of the present application with reference to the accompanying drawings in embodiments of the present application. Apparently, the described embodiments are merely a part rather than all embodiments of the present application.

The following embodiments and the features in the embodiments can be combined with each other in the absence of conflict.

In the solution of the related art, a cooling system that is provided on an electric vehicle includes an expansion tank, a liquid-air separator, an electronic water pump, a part to be cooled (such as a battery pack, a motor, etc.), and a heat exchanger. The liquid-air separator, the electronic water pump, the part to be cooled, and the heat exchanger are connected in turn by pipelines to form a closed-loop circuit. The expansion tank is connected to the liquid-air separator by a pipeline, thereby absorbing the air separated from the liquid-air separator or supplementing a cooling liquid to the liquid-air separator. When in use, the electronic water pump is started to drive the cooling liquid and a gas to flow into the part to be cooled and take heat away, then the cooling liquid enters the heat exchanger for cooling; and the cooling liquid flowing out from the heat exchanger enters the liquid-gas separator for gas-liquid separating, where the gas flows into the expansion tank and the separated cooling liquid flows into the electronic water pump for continuing to perform cooling cycle.

In view of the above, the present application aims to provide an expansion tank, a cooling system, and a vehicle, the function of gas-liquid separation is integrated in the expansion tank by changing the inlet and outlet structure and the internal structure of the expansion tank, so that the liquid-air separator and some pipelines can be removed from the cooling system, thereby facilitating the reduction of the number and total weight of parts in the cooling system, the reduction of the number of pipelines in the cooling system, and the reduction of the costs, and facilitating the lightweight of the vehicle.

The following will describe in detail the contents of embodiments of the present application in combination with the accompanying drawings, so that persons of ordinary skill in the art can understand the contents of the present application in more detail.

<FIG> is a schematic diagram of a structure of an expansion tank provided in an example of the present application; <FIG> is a schematic diagram of a connection structure of pipes and other equipment provided in an embodiment of the present application; <FIG> is an exploded view of an expansion tank provided in an embodiment of the present application; and <FIG> is a flow direction diagram of a mixed liquid in an expansion tank provided in an embodiment of the present application.

Referring to <FIG>, an embodiment provides an expansion tank <NUM>, including a tank body <NUM>, a first partition <NUM> is provided within the tank body <NUM>, the first partition <NUM> divides an interior of the tank body <NUM> into a first chamber <NUM> and a second chamber <NUM>, the first partition <NUM> is provided with a first through hole <NUM>, and the first chamber <NUM> communicates with the second chamber <NUM> through first through hole <NUM>.

Specifically, the tank body <NUM> may be made of a material such as plastic, the tank body <NUM> is generally cylindrical or prismatic in shape, the tank body <NUM> may be provided with a protruding portion to make the interior of the tank body <NUM> have a larger volume.

The first partition <NUM> can be extended along a direction of gravity to divide the tank body <NUM> into the first chamber <NUM> and the second chamber <NUM>, the specific sizes of the first chamber <NUM> and the second chamber <NUM> can be determined as needed. The first through hole <NUM> is provided between the first chamber <NUM> and the second chamber <NUM>, there is a certain gap between the first through hole <NUM> and a bottom of the tank body <NUM> to ensure that a cooling liquid in the first chamber <NUM> will flow into the second chamber <NUM> after exceeding a certain height.

The tank body <NUM> is further provided with a pipe <NUM> communicating with the interior of the tank body <NUM>, the pipe <NUM> can also be made of a plastic material, the shape of the cross-section of the pipe <NUM> may be a circle, a rectangle, or a triangle, preferably a pipe with a circular cross-section is used. A side wall of the pipe <NUM> is provided with a mixed liquid inlet <NUM>, the mixed liquid inlet <NUM> is connected to a pipeline of the cooling system to introduce a mixed liquid including a cooling liquid and a gas into the tank body <NUM>. A second partition <NUM> is provided within the pipe <NUM>, the second partition <NUM> is provided along an axial direction of the tank body <NUM>, one end of the second partition <NUM> is connected to the side wall of the pipe <NUM> and the other end of the second partition <NUM> extends to the mixed liquid inlet <NUM> so as to form a first channel <NUM> and a second channel <NUM> within the pipe <NUM>. It is understood that the first channel <NUM> and the second channel <NUM> are also extend along the axial direction of the pipe <NUM>. The mixed liquid inlet <NUM> is simultaneously connected to a side wall of the first channel <NUM> and a side wall of the second channel <NUM> to make the mixed liquid flow into both the first channel <NUM> and the second channel <NUM>. In a direction perpendicular to an axis of the mixed liquid inlet <NUM>, a first end of the first channel <NUM> is connected to the first chamber <NUM>, a second end of the first channel <NUM> is closed, a first end of the second channel <NUM> is connected to the second chamber <NUM>, a second end of the second channel <NUM> is configured to connect a water pump <NUM>. Since the second end of the first channel <NUM> is closed, the mixed liquid entering the first channel <NUM> is only able to enter the first chamber <NUM> within the tank body <NUM>, while the mixed liquid entering the second channel <NUM> is able to directly flow into the water pump <NUM>.

When the expansion tank <NUM> of the present embodiment is in use, the mixed liquid of the cooling liquid and gas simultaneously flows into the first channel <NUM> and the second channel <NUM> through the mixed liquid inlet <NUM>. The mixed liquid flowing into the second channel <NUM> flows directly into the water pump <NUM>; the mixed liquid flowing into the first channel <NUM> enters the first chamber <NUM>. The gas and cooling liquid are separated in the first chamber <NUM> under the action of gravity, the separated gas is stored in the expansion tank <NUM>, and the separated gas can be discharged through a pressure valve on the tank body <NUM> when the pressure reaches a certain value; the separated cooling liquid enters the second chamber <NUM> through the first through hole <NUM> and flows into the water pump <NUM> through the second channel <NUM>. By the way as described above, the expansion tank <NUM> of the present embodiment has a better function of gas-liquid separation, and can reduce the content of gas in the cooling liquid entering the water pump, thereby facilitating the normal operation of the cooling system.

Since the expansion tank <NUM> of the present embodiment has the function of gas-liquid separation, there is no need to provide a special liquid-gas separator in the cooling system, thereby facilitating the reduction of the number and total weight of parts in the cooling system, the reduction of the number of pipelines in the cooling system, and the reduction of the costs, and facilitating the lightweight of the vehicle.

In a possible implementation, in the present embodiment, the area of the mixed liquid inlet <NUM> communicating with the first channel <NUM> is smaller than the area of the mixed liquid inlet <NUM> communicating with the second channel <NUM>. This makes the volume of the mixed liquid entering the first chamber <NUM> smaller than the volume of the mixed liquid entering the second chamber <NUM> per unit time, thereby achieving gas-liquid separation in the mixed liquid while ensuring normal cycle.

Optionally, the area of the mixed liquid inlet <NUM> communicating with the first channel <NUM> may be <NUM>-<NUM>% of the area of the mixed liquid inlet <NUM> communicating with the second channel <NUM>.

In the present embodiment, an end cap <NUM> is provided on the second end of the first channel <NUM>, and the end cap <NUM> is fixedly connected to the pipe <NUM> and the second partition <NUM>. When the shape of the cross-section of the pipe <NUM> is a circle, the shape of the cross-section of the first channel <NUM> is generally a semicircle, so that the shape of the end cap <NUM> may also be a semicircle. The material of end cap <NUM> is same as that of the tank body <NUM>, and bonding, hot plate welding, etc. may be used for specific connection and fixation.

Optionally, the pipe <NUM> in the present embodiment is cylindrical or prismatic in shape, an axis of the pipe <NUM> is perpendicular with the axis of the mixed liquid inlet <NUM>. When in use, the mixed liquid flows into the first channel <NUM> and the second channel <NUM> in a horizontal direction, the mixed liquid flowing into the second channel <NUM> flows directly into the water pump under the influence of gravity; the mixed liquid flowing into the first channel <NUM> gradually accumulates to the interior of the first chamber <NUM> due to the blockage of the end cap <NUM>. Because the gas is lighter, the gas in the mixed liquid is gradually separated to the top of the first chamber <NUM> under the action of gravity, while the liquid accumulates to the bottom of the first chamber <NUM>. When the liquid accumulates to a certain height, it flows into the second chamber <NUM> through the first through hole <NUM> and flows into the water pump under the action of gravity.

Optionally, the tank body <NUM> of the present embodiment includes a first sub-tank body <NUM> and a second sub-tank body <NUM>, the first sub-tank body <NUM> and the second sub-tank body <NUM> are welded to form the tank body <NUM>. The first sub-tank body <NUM> and the second sub-tank body <NUM> can be divided along a plane perpendicular to the axial direction of the pipe <NUM>, and parts of the first chamber <NUM>, of the second chamber <NUM>, of the first partition <NUM>, and of the second partition <NUM> are included within each of the first sub-tank body <NUM> and the second sub-tank body <NUM>. The first sub-tank body <NUM> and the second sub-tank body <NUM> form a complete tank body <NUM> after being combined by hot plate welding. The tank body <NUM> using split design facilitates setting of the structure within the tank body <NUM> and is conducive to improving the accuracy of the production.

Further, the first chamber <NUM> of the present embodiment may include a plurality of first sub-chambers <NUM>, a third partition <NUM> is provided between two adjacent first sub-chambers <NUM>, the third partition <NUM> is provided with a third through hole <NUM>. The second chamber <NUM> may include a plurality of second sub-chambers <NUM>, a fourth partition <NUM> is provided between two adjacent second sub-chambers <NUM>, the fourth partition <NUM> is provided with a fourth through hole <NUM>. The third partition <NUM> and the fourth partition <NUM> are parallel to each other. In other words, in the present embodiment the first chamber <NUM> and the second chamber <NUM> can be divided into a plurality of small chambers that are communicated with each other. Such arrangement, on the one hand, is conducive to enhancing the efficiency of gas-liquid separation inside the tank body <NUM>, and on the other hand, to enhancing the strength of the tank body <NUM> using the third partition <NUM> and the fourth partition <NUM>.

Optionally, in the present embodiment, the first through hole <NUM> is provided between the first sub-chambers <NUM> and the second sub-chambers <NUM> adjacent to the first sub-chambers <NUM>, thereby facilitating gas-liquid separation and increasing the speed of the cooling liquid entering the second chamber <NUM>.

Alternatively, the first through hole <NUM> is provided between one first sub-chamber <NUM> of the first sub-chambers <NUM> and one second sub-chamber <NUM> of the second sub-chambers <NUM> adjacent to the one first sub-chamber <NUM>, and preferably may be provided between a first sub-chamber <NUM> located in a middle position and a second sub-chamber <NUM> adjacent thereto.

Furthermore, in order to enhance the strength of the tank body <NUM>, a plurality of reinforcing ribs <NUM> are also provided within the tank body <NUM>, the reinforcing ribs <NUM> may be provided along a direction parallel to the first partition <NUM>, or may also be provided along a direction parallel to the third partition <NUM>.

As can be seen from the above description, in the expansion tank <NUM> of the present embodiment, the first chamber <NUM> and the second chamber <NUM> that communicate with each other are provided within the tank body <NUM>. The side wall of the pipe <NUM> communicating with the tank body <NUM> is provided with the mixed liquid inlet <NUM>, the first channel <NUM> and the second channel <NUM> are formed within the pipe <NUM> by the second partition <NUM>, one end of the first channel <NUM> is closed and the other end of that is connected to the first chamber <NUM>, the second channel <NUM> is connected to the second chamber and the water pump. After the mixed liquid flows into the pipe <NUM>, the mixed liquid flowing into the second channel <NUM> flows directly into the water pump; the mixed liquid flowing into the first channel <NUM> enters the first chamber <NUM>, the gas and cooling liquid are separated within the first chamber <NUM> under the action of gravity, the separated gas is stored in the expansion tank <NUM>, and the separated cooling liquid enters the second chamber <NUM> through the first through hole <NUM> and flows into the water pump through the second channel <NUM>. Thus, the expansion tank <NUM> of the present embodiment also has the function of gas-liquid separation, so there is no need to provide a special liquid-gas separator in the cooling system, thereby facilitating the reduction of the number and total weight of parts in the cooling system, the reduction of the number of pipelines in the cooling system and the reduction of the costs, and facilitating the lightweight of the vehicle.

<FIG> is a schematic diagram of a structure of a cooling system provided in an embodiment of the present application.

Referring to <FIG>, the present embodiment provides a cooling system including a water pump <NUM>, a part to be cooled <NUM>, a heat exchanger <NUM>, and an expansion tank <NUM> as any one of described above, and the water pump <NUM>, the part to be cooled <NUM>, the heat exchanger <NUM>, and the expansion tank <NUM> are connected in turn by pipelines, where the heat exchanger <NUM> is connected to the mixed liquid inlet of the expansion tank <NUM>, the second channel of the expansion tank <NUM> is connected to the water pump <NUM>.

Specifically, the part to be cooled <NUM> in the present embodiment can be an engine, motor, or battery pack, and the like. The water pump <NUM> is used to provide circulating power for the whole system, the mixed liquid of the cooling liquid and gas can circularly flow along the pipeline in the system under the action of the water pump <NUM> to reduce the temperature of the part to be cooled <NUM>. Since the expansion tank <NUM> of Example <NUM> is provided, the mixed liquid can realize gas-liquid separation in the expansion tank <NUM>, thus reducing the amount of gas that circulates within the cooling system, and eliminating the need of installing a special liquid-gas separator in the cooling system, thereby facilitating the reduction of the number and total weight of parts in the cooling system, the reduction of the number of pipelines in the cooling system, and the reduction of the costs, and facilitating the lightweight of the vehicle.

The present embodiment provides a vehicle including a cooling system in Example <NUM> as described above.

Specifically, the cooling system in the present embodiment can be located in an engine compartment of the vehicle or in a space between a chassis and a body of the vehicle. For the vehicle of the present embodiment, since the cooling system in Example <NUM> as described above is used, no special liquid-gas separator is needed to provide in the cooling system, thereby facilitating the reduction of the number and total weight of parts in the cooling system, the reduction of the number of pipelines in the cooling system, and the reduction of the costs, and facilitating the lightweight of the vehicle.

In the description of the present application, it is to be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, only to facilitate the description of the present application and simplify the description, and not to indicate or imply that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be interpreted as a limitation to the present application.

In the present application, unless otherwise expressly specified and limited, the terms "mounted", "linked", "connected", "fixed", etc. shall be understood in a broad sense, for example, the connection may be fixed connection, detachable connection, integrated connection, direct connection, indirect connection by an intermediate medium, interconnection between the interiors of two components, or an interaction relationship between two components. For persons of ordinary skill in the art, the specific meanings of the aforesaid terms in the present application can be understood based on the specific situations.

It should be noted that in the description of the present application, the terms "first" and "second" are only used to facilitate the description of different components and are not to be understood as indicating or implying a sequential relationship, relative importance, or implicitly specifying the number of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature.

Claim 1:
An expansion tank (<NUM>), comprising a tank body (<NUM>), a first partition (<NUM>) is provided within the tank body (<NUM>), the first partition (<NUM>) divides an interior of the tank body (<NUM>) into a first chamber (<NUM>) and a second chamber (<NUM>), the first partition (<NUM>) is provided with a first through hole (<NUM>), and the first chamber (<NUM>) communicates with the second chamber (<NUM>) through the first through hole (<NUM>);
the tank body (<NUM>) is provided with a pipe (<NUM>) communicating with an interior of the tank body (<NUM>), and a side wall of the pipe (<NUM>) is provided with a mixed liquid inlet (<NUM>);
characterized in that,
a second partition (<NUM>) is provided within the pipe (<NUM>), one end of the second partition (<NUM>) is connected to the side wall of the pipe (<NUM>) and the other end of the second partition (<NUM>) extends to the mixed liquid inlet (<NUM>) so as to form a first channel (<NUM>) and a second channel (<NUM>) within the pipe (<NUM>); the mixed liquid inlet (<NUM>) is simultaneously connected to a side wall of the first channel (<NUM>) and a side wall of the second channel (<NUM>); in a direction perpendicular to an axis of the mixed liquid inlet (<NUM>), a first end of the first channel (<NUM>) is connected to the first chamber (<NUM>), a second end of the first channel (<NUM>) is closed, a first end of the second channel (<NUM>) is connected to the second chamber, a second end of the second channel (<NUM>) is configured to be connected to a water pump.