CN218544791U

CN218544791U - Hydraulic center and air conditioner circulating water system with same

Info

Publication number: CN218544791U
Application number: CN202121957920.4U
Authority: CN
Inventors: 陈龙; 朱胜民
Original assignee: Zhejiang Intech Technology Co ltd
Current assignee: Zhejiang Intech Technology Co ltd
Priority date: 2021-08-19
Filing date: 2021-08-19
Publication date: 2023-02-28
Anticipated expiration: 2031-08-19

Abstract

The utility model relates to an air conditioning system field especially relates to a water conservancy center and have air conditioner circulating water system at this water conservancy center. The hydraulic center comprises a box body, a water return pipeline connected with the main machine, a water outlet pipeline connected with the main machine, a water return pipeline connected with the tail end, a water supplementing pipeline and at least one water outlet pipeline connected with the tail end, wherein the water return pipeline, the water outlet pipeline and the water supplementing pipeline are arranged in the box body; it is characterized in that; a water tank is connected between a water return pipeline connected with the tail end in the box body and a water outlet pipeline connected with the main machine, and the inner end part of the water supplementing pipeline is connected to the water return pipeline or the water tank connected with the tail end. The water tank of the scheme is connected to the water outlet pipeline of the main machine, so that sufficient running water is ensured in the water outlet pipeline of the main machine, and the phenomenon of suction of the water outlet pipeline of the main machine when the water pump is started is avoided.

Description

Hydraulic center and air conditioner circulating water system with same

Technical Field

The utility model relates to an air conditioning system field especially relates to a water conservancy center and have air conditioner circulating water system at this water conservancy center.

Background

The hydraulic module integrates a water pump, a valve piece, a filter, a constant-pressure water replenishing device, a water pump control electric control cabinet and the like (almost all things except a main machine and a tail end) into a box; the device is suitable for circulating delivery of air conditioning water, cooling water and sanitary hot water of a central air conditioning water system and delivery of other aqueous media. The existing hydraulic module can refer to a non-negative pressure hydraulic module for an air conditioning unit, which is referred to in a Chinese utility model patent text with the publication number of CN207797343U, and an air conditioning hydraulic module with a descaling function, which is referred to in a Chinese utility model patent text with the publication number of CN 208952480U. In the prior art, only the performing function in the pipeline is provided within the hydro module. After the water conservancy module is connected to in the closed circulation system, if the water distribution in the closed circulation system is inhomogeneous, then the water pump leads to the vacuummate phenomenon of appearance of return water pipeline easily when starting.

Disclosure of Invention

In order to solve the problem, the utility model discloses a first aim at provides a hydraulic center, and the water tank of this scheme is connected at the outlet conduit who connects the host computer, is favorable to guaranteeing to have sufficient operation water yield in the outlet conduit who connects the host computer to when avoiding the water pump to start, connect the appearance of the outlet conduit of host computer to inhale empty phenomenon.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

the hydraulic center comprises a box body, a water return pipeline connected with the main machine, a water outlet pipeline connected with the main machine, a water return pipeline connected with the tail end, a water supplementing pipeline and at least one water outlet pipeline connected with the tail end, wherein the water return pipeline, the water supplementing pipeline and the at least one water outlet pipeline are arranged in the box body; the water return pipeline of the main connecting machine is used for connecting a water outlet of the main air conditioner, and the water outlet pipeline of the main connecting machine is used for connecting a water inlet of the main air conditioner; the water return pipeline connected with the tail end is used for connecting the water outlet at the tail end, and the water outlet pipeline connected with the tail end is used for connecting the water inlet at the tail end; it is characterized in that; and a water tank is connected between a water return pipeline connected with the tail end in the box body and a water outlet pipeline connected with the main machine, and the inner end part of the water supplementing pipeline is connected to the water return pipeline or the water tank connected with the tail end.

The utility model adopts the above technical scheme, the technical scheme relates to a hydraulic center, the water return pipeline of the host machine is arranged in the hydraulic center and is used for connecting the water outlet of the air conditioner host machine, and the water outlet pipeline of the host machine is used for connecting the water inlet of the air conditioner host machine; the water return pipeline connected with the tail end is used for being connected with the water outlet at the tail end, and the water outlet pipeline connected with the tail end is used for being connected with the water inlet at the tail end. In the scheme, a water tank is connected between a water return pipeline connected with the tail end and a water outlet pipeline connected with the main machine; the water tank is constructed in the box body of the hydraulic center and is connected in the system, so that the running water quantity in the air-conditioning system can be increased, and the running stability of the air-conditioning system is ensured; on the basis, the water tank of the scheme is connected with the water outlet pipeline of the main machine, so that sufficient running water quantity in the water outlet pipeline of the main machine is favorably ensured, and the phenomenon of suction of the water outlet pipeline of the main machine when the water pump is started is avoided.

Preferably, an expansion air bag is arranged in the tank body of the water tank and is used for stabilizing the water pressure of the water tank and the connecting pipeline of the water tank.

As mentioned in the background art, an expansion tank is required to be arranged in the traditional hydraulic center, and the expansion tank can reduce the water pressure fluctuation of the system caused by the expansion of water, thereby improving the safety and the reliability of the operation of the system. In the technical scheme, the expansion airbag is arranged in the water tank, namely, the expansion function of the expansion airbag is combined on the basis of the water storage function of the water tank, so that the function of the expansion tank is achieved.

According to the scheme, the expansion structure is arranged in the water tank, and the existing water tank and the existing expansion tank are combined functionally, so that the structure is simplified, and the occupied space of the system is reduced.

Preferably, a limit frame used for limiting the range of the expansion air bag is further arranged inside the tank body of the water tank; the expansion air bag is arranged in the limiting frame, and the limiting frame is provided with a water permeable hole. This scheme adopts spacing frame to limit the inflation region of inflation gasbag to avoid the inflation gasbag that expands too big. The limiting frame is provided with a water permeable hole, and the water storage cavity of the shell is communicated with an expansion area framed by the limiting frame, so that the water pressure of the water storage cavity and a connecting pipeline of the water storage cavity can be controlled based on the expansion and contraction of the expansion air bag.

Preferably, a differential pressure balancing pipeline and a differential pressure balancing valve connected to the differential pressure balancing pipeline are further arranged in the box body; one end of the differential pressure balance pipeline is connected to the water outlet pipeline at the tail end, and the other end of the differential pressure balance pipeline is connected to the water return pipeline or the water tank at the tail end. According to the technical scheme, the pressure difference balance pipeline and the pressure difference balance valve connected with the pressure difference balance pipeline can enable the pressure difference between the water outlet pipeline connected with the tail end and the water return pipeline connected with the tail end to be kept within a certain range, and unstable system operation caused by too large and too small pressure difference under the conditions of opening and closing of the two-way valve at the tail end of the air conditioner and the like is avoided.

Preferably, a flow sensor for acquiring the amount of water to be supplemented is arranged on the water supplementing pipeline, a first pressure sensor for acquiring the pressure of outlet water is arranged on the water returning pipeline connected with the host or the water outlet pipeline connected with the tail end, and a second pressure sensor for acquiring the pressure of the return water is arranged on the water returning pipeline or the water tank connected with the tail end; the controller can judge whether the system has a water leakage condition or not based on the water supplementing amount of the flow sensor, the water outlet pressure obtained by the first pressure sensor and/or the water return pressure obtained by the second pressure sensor. In the technical scheme, the water supplementing pipeline is used for supplementing water when the running water quantity in the closed circulation system is reduced, a water supplementing valve on the water supplementing pipeline is used for controlling the on-off of the water supplementing pipeline, and the flow sensor is used for acquiring the water supplementing quantity. Furthermore, a first pressure sensor is arranged in the hydraulic center to acquire water outlet pressure, and a second pressure sensor acquires water return pressure.

Based on the water replenishing quantity, the water outlet pressure and the water return pressure which are obtained in unit time, the controller can judge whether the running water quantity in the closed circulation system is normally reduced or not and whether the condition of pipeline leakage exists or not.

Preferably, a first temperature sensor for acquiring the outlet water temperature is arranged on the water outlet pipeline at the connection tail end, and a second temperature sensor for acquiring the return water temperature is arranged on the return water pipeline or the water tank at the connection tail end; the controller more accurately judges whether the system has water leakage conditions according to the historical data of the water outlet temperature and/or the water return temperature. According to the scheme, the influence of the water temperature in the system on the volume and the pressure of the liquid is considered, so that the outlet water temperature and the return water temperature are detected in the scheme, and the influence of the temperature on the water pressure is judged by combining the historical data of the outlet water temperature and/or the return water temperature; when judging whether the running water quantity in the closed circulation system is reduced normally, the influence of the temperature on the water pressure is eliminated, and whether the water leakage condition exists in the system is judged more accurately.

Preferably, a drain valve is arranged at the bottom of the water tank, and a water supplementing valve is arranged on the water supplementing pipeline; and when the controller judges that the water leakage condition exists based on the acquired data and logic reasoning, the water supplementing valve is closed, the drain valve is opened or the water supplementing valve is closed, and sound and light alarm is performed.

Preferably, the top of the water tank is provided with an air exhaust device, the air exhaust device is an automatic air exhaust device or a spiral air exhaust device, and the automatic air exhaust device or the spiral air exhaust device extends to the outer side of the water tank and is communicated with the outside through an air exhaust port. The scheme considers that bubbles are likely to be generated when pipelines are arranged, when the pipelines are supplemented with water and when running water is heated, and oxygen in the bubbles is extremely easy to corrode the pipelines, so that the scheme is that an exhaust device is arranged on the water tank and can be used for exhausting the bubbles in the pipelines and prolonging the service life of the pipelines.

Preferably, the water tank is provided with a safety valve and/or an electric heating device, and the water replenishing pipeline is provided with a filter and/or a check valve. The safety valve in the scheme has the function that when the pressure of a medium in the water tank rises to exceed a specified value, the medium is discharged to the outside of the system; the electric heating device is used for performing auxiliary heating on the function of the air conditioner main machine, so that the heating requirement in winter is ensured; the filter is used for filtering the supplemented water; the check valve prevents the medium in the system from flowing back from the water replenishing pipeline.

Preferably, the number of the water outlet pipelines connected with the tail end is two, and one water outlet pipeline connected with the tail end is provided with a control valve. Two water outlet pipelines connected with the tail ends in the technical scheme are used for being connected with the tail ends of an air conditioner (such as a fan coil, a floor heating piece and a heating piece), wherein the fan coil can be used in winter and summer, and the floor heating piece and the heating piece can be used only in winter. Therefore, the scheme is provided with at least two water outlet pipelines connected with the tail ends, one of the water outlet pipelines connected with the tail ends can be selectively closed, and the flowing direction of the internal running water is controlled.

A second object of the present invention is to provide an air-conditioning circulating water system, which comprises an air-conditioning main unit, a hydraulic center and a tail end; a hydraulic center as described above for the hydraulic center; the water return pipeline of the host is connected with the water outlet of the air-conditioning host, and the water outlet pipeline of the host is connected with the water inlet of the air-conditioning host; the water return pipeline connected with the tail end is connected with the water outlet at the tail end, and the water outlet pipeline connected with the tail end is connected with the water inlet at the tail end; the water pump is arranged on the air conditioner host, the hydraulic center or a system pipeline.

In a further preferred scheme, when the tail end comprises a fan coil, a floor heating and heating sheet, the fan coil is connected with the downstream of the water outlet pipeline of one of the tail ends, and the floor heating and heating sheet is connected in parallel with the downstream of the water outlet pipeline of the other tail end. When the tail end of an air conditioner connected with an air conditioner circulating water system comprises a fan coil, a floor heater and a heating sheet, as described above, the fan coil, the floor heater and the heating sheet are different in use seasons, so that the system connects the fan coil to the downstream of the water outlet pipeline of one terminal, and connects the floor heater and the heating sheet to the downstream of the water outlet pipeline of the other terminal in parallel; in summer refrigeration environment, the valve can be closed through a control valve on the other water outlet pipeline connected with the tail end.

Drawings

Fig. 1 is a schematic view of the hydraulic center structure described in example 1.

Fig. 2 is a schematic structural view of an air-conditioning circulating water system described in embodiment 2.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present invention, and should not be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and to simplify the description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, unless otherwise specified, "a plurality" means two or more unless explicitly defined otherwise.

In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood according to specific situations by those of ordinary skill in the art.

In the present disclosure, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise direct contact between the first and second features, or may comprise contact between the first and second features not directly. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

Example 1:

as shown in fig. 1, the present embodiment relates to a hydraulic center, which comprises a box 1, and a return pipe 111 connected to a main machine, a water outlet pipe 112 connected to the main machine, a return pipe 113 connected to a tail end, a water replenishing pipe 13, and at least one water outlet pipe 114 connected to the tail end, which are arranged inside the box 1; the water return pipeline 111 of the host is used for connecting a water outlet of the air-conditioning host 2, and the water outlet pipeline 112 of the host is used for connecting a water inlet of the air-conditioning host 2; the water return line 113 connected to the end is used for connecting the water outlet of the end, and the water outlet line 114 connected to the end is used for connecting the water inlet of the end.

In this embodiment, the water tank 3 is connected between the water return line 113 connected to the end of the tank 1 and the water outlet line 112 connected to the main unit, and the inner end of the water supply line 13 is connected to the water return line 113 connected to the end or the water tank 3. The water tank is constructed in the box body of the hydraulic center and is connected in the system, so that the running water quantity in the air-conditioning system can be increased, and the running stability of the air-conditioning system is ensured; on the basis, the water tank of the scheme is connected with the water outlet pipeline of the main machine, so that sufficient running water quantity in the water outlet pipeline of the main machine is guaranteed, and the phenomenon of air suction of the water outlet pipeline of the main machine when the water pump is started is avoided.

Specifically, as shown in the figure, there are two of the terminal water outlet pipes 114, and one of the terminal water outlet pipes 114 is provided with a control valve 115. In the technical scheme, the two water outlet pipelines 114 connected with the tail ends are used for connecting the tail ends of an air conditioner (such as a fan coil, a floor heating piece and a heating piece), wherein the fan coil can be used in winter and summer, and the floor heating piece and the heating piece can be used only in winter. Therefore, the scheme is provided with at least two water outlet pipes 114 connected with the tail end, and the water outlet pipe 114 connected with one tail end can be selectively closed, so as to control the flowing direction of the internal running water.

In a further embodiment, an inner end of the water supply line 13 is connected to the water return line 113 or the water tank 3, and the water supply line 13 is provided with a water supply valve 131, a filter 134, a flow sensor 133, and a check valve 132. The water replenishing valve 131 in the scheme is used for controlling the on-off of the water replenishing pipeline 13, and the filter 134 is used for filtering the replenished water; the check valve 132 prevents the medium inside the system from flowing back from the water replenishing pipeline; the flow sensor 133 is used to obtain the amount of water supplement.

A differential pressure balance pipeline 14 and a differential pressure balance valve 141 connected to the differential pressure balance pipeline 14 are also arranged in the box body 1; one end of the differential pressure equalizing line 14 is connected to the water outlet line 114 of the junction, and the other end of the differential pressure equalizing line 14 is connected to the water return line 113 or the water tank 3 of the junction. According to the technical scheme, the pressure difference balance pipeline and the pressure difference balance valve connected with the pressure difference balance pipeline can enable the pressure difference between the water outlet pipeline connected with the tail end and the water return pipeline connected with the tail end to be kept within a certain range, and unstable system operation caused by too large and too small pressure difference under the conditions of opening and closing of the two-way valve at the tail end of the air conditioner and the like is avoided.

In a further preferred scheme, a first pressure sensor 31 for acquiring outlet water pressure is arranged on the return pipeline 111 connected to the main machine or the outlet pipeline 114 connected to the tail end, and a second pressure sensor 41 for acquiring return water pressure is arranged on the return pipeline 113 connected to the tail end or the water tank 3; the controller can determine whether the system has a water leakage condition based on the amount of water replenished by the flow sensor 133, the water outlet pressure obtained by the first pressure sensor 31 and/or the water return pressure obtained by the second pressure sensor 41. In the technical scheme, the controller can judge whether the running water quantity in the closed circulation system is reduced normally or not and whether the condition of pipeline leakage exists or not based on the water supplementing quantity, the water outlet pressure and the water return pressure which are obtained in unit time.

In a more preferable scheme, a first temperature sensor for acquiring the outlet water temperature is arranged on the outlet water pipeline 114 connected with the tail end, and a second temperature sensor 42 for acquiring the return water temperature is arranged on the return water pipeline 113 or the water tank 3 connected with the tail end; the controller more accurately judges whether the system has water leakage conditions according to the historical data of the water outlet temperature and/or the water return temperature. According to the scheme, the influence of the water temperature in the system on the volume and the pressure of the liquid is considered, so that the outlet water temperature and the return water temperature are detected in the scheme, and the influence of the temperature on the water pressure is judged by combining the historical data of the outlet water temperature and/or the return water temperature; when judging whether the running water quantity in the closed circulation system is reduced normally, the influence of the temperature on the water pressure is eliminated, and whether the water leakage condition exists in the system is judged more accurately.

In addition, as shown in the figure, a drain valve 33 is arranged at the bottom of the water tank 3, and when the controller judges that a water leakage condition exists based on the collected data and logic reasoning, the water supplementing valve 131 is closed, the drain valve 33 is opened or the water supplementing valve 131 is closed, and sound and light alarm is given.

The top of the water tank 3 is provided with an air exhaust device 34, the air exhaust device 34 is an automatic air exhaust device or a spiral air exhaust device, and the automatic air exhaust device or the spiral air exhaust device extends to the outer side of the water tank 3 and is communicated with the outside through an air exhaust port 35. The scheme considers that bubbles are likely to be generated when pipelines are arranged, when the pipelines are supplemented with water and when running water is heated, and oxygen in the bubbles is extremely easy to corrode the pipelines, so that the scheme is that an exhaust device is arranged on the water tank and can be used for exhausting the bubbles in the pipelines and prolonging the service life of the pipelines.

In addition, the water tank 3 is provided with a safety valve 44 and/or an electric heating device 37, and the safety valve in the scheme has the function of discharging media to the outside of the system when the pressure of the media in the water tank is increased to exceed a specified value; the electric heating device 37 performs auxiliary heating on the function of the air conditioner main unit 2, so as to ensure the heating requirement in winter.

Finally, an expansion air bag 80 is arranged inside the tank body of the water tank 3, and the expansion air bag 80 is used for stabilizing the water pressure of the water tank 3 and the connecting pipeline thereof. As mentioned in the background art, an expansion tank is required to be arranged in the traditional hydraulic center, and the expansion tank can reduce the water pressure fluctuation of the system caused by the expansion of water, thereby improving the safety and the reliability of the operation of the system. In the technical scheme, the expansion airbag is arranged in the water tank, namely, the expansion function of the expansion airbag is combined on the basis of the water storage function of the water tank, so that the function of the expansion tank is achieved. According to the scheme, the expansion structure is arranged in the water tank, and the existing water tank and the expansion tank are combined functionally, so that the structure is simplified, and the occupied space of the system is reduced.

In a further scheme, a limit frame 81 for limiting the range of the expansion air bag 80 is further arranged in the box body of the water tank 3; the expansion air bag 80 is arranged in the limiting frame 81, and the limiting frame 81 is provided with a water permeable hole. This scheme adopts spacing frame to limit the inflation region of inflation gasbag to avoid the inflation gasbag that expands too big. The limiting frame 81 is provided with a water permeable hole, and the purpose of the water permeable hole is to enable the water storage cavity of the shell to be communicated with an expansion area defined by the limiting frame 81, so that the water pressure of the water storage cavity and a connecting pipeline of the water storage cavity can be controlled based on the expansion and contraction of the expansion air bag.

Example 2:

as shown in fig. 2, the present embodiment provides an air-conditioning circulating water system, which includes an air-conditioning main unit 2, a hydraulic center, and a tail end. The hydraulic center as described in example 1 of the hydraulic center, of course, also includes the water tank with the inflatable bladder of example 1. The water return pipeline 111 of the host is connected with the water outlet of the air-conditioning host 2, and the water outlet pipeline 112 of the host is connected with the water inlet of the air-conditioning host 2; the water return pipeline 113 connected with the tail end is connected with the water outlet of the tail end, and the water outlet pipeline 114 connected with the tail end is connected with the water inlet of the tail end; the heat exchanger 21 is arranged in the air conditioner main machine 2, and the water pump 51 is arranged on the air conditioner main machine 2, the hydraulic center 1 or a system pipeline.

In a further preferred scheme, when the terminals include the fan coil 52, the floor heating 53 and the heating sheet 54, the fan coil 52 is connected to the downstream of the water outlet pipeline 114 of one terminal, and the floor heating 53 and the heating sheet 54 are connected in parallel to the downstream of the water outlet pipeline 114 of the other terminal. When the air conditioner tail end connected with the air conditioner circulating water system comprises the fan coil, the floor heating and the heating sheet, as mentioned above, the use seasons of the fan coil, the floor heating and the heating sheet are different, so that the system connects the fan coil to the downstream of the water outlet pipeline 114 of one of the tail ends, and connects the floor heating and the heating sheet to the downstream of the water outlet pipeline 114 of the other tail end in parallel; in summer refrigeration environments, the valve may be closed by a control valve on the other, terminal, water outlet line 114.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although embodiments of the present invention have been shown and described, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that changes, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art without departing from the principles and spirit of the present invention.

Claims

1. The hydraulic center comprises a box body (1), a water return pipeline (111) connected with a main machine, a water outlet pipeline (112) connected with the main machine, a water return pipeline (113) connected with the tail end, a water supplementing pipeline (13) and at least one water outlet pipeline (114) connected with the tail end, wherein the water return pipeline (111), the water outlet pipeline (112) and the water supplementing pipeline are arranged in the box body (1); the water return pipeline (111) connected with the main unit is used for being connected with a water outlet of the air-conditioning main unit (2), and the water outlet pipeline (112) connected with the main unit is used for being connected with a water inlet of the air-conditioning main unit (2); the water return pipeline (113) connected with the tail end is used for connecting the water outlet of the tail end, and the water outlet pipeline (114) connected with the tail end is used for connecting the water inlet of the tail end; it is characterized in that; a water tank (3) is connected between a water return pipeline (113) connected with the tail end in the box body (1) and a water outlet pipeline (112) connected with the main machine, and the inner end part of the water supplementing pipeline (13) is connected to the water return pipeline (113) or the water tank (3) connected with the tail end.

2. The hydraulic center of claim 1, wherein: an expansion air bag (80) is arranged in the tank body of the water tank (3), and the expansion air bag (80) is used for stabilizing the water pressure of the water tank (3) and a connecting pipeline thereof.

3. The hydraulic center of claim 2, wherein: a limiting frame (81) used for limiting the range of the expansion air bag (80) is further arranged in the box body of the water tank (3); the inflatable air bag (80) is arranged in the limiting frame (81), and the limiting frame (81) is provided with water permeable holes.

4. The hydraulic center of claim 1, wherein: the box body (1) is also internally provided with a differential pressure balancing pipeline (14) and a differential pressure balancing valve (141) connected to the differential pressure balancing pipeline (14); one end of the differential pressure balancing pipeline (14) is connected to the water outlet pipeline (114) at the tail end, and the other end of the differential pressure balancing pipeline (14) is connected to the water return pipeline (113) or the water tank (3) at the tail end.

5. The hydraulic center of claim 1, wherein: a flow sensor (133) for acquiring the amount of water to be supplemented is arranged on the water supplementing pipeline (13), a first pressure sensor (31) for acquiring the pressure of outlet water is arranged on the water return pipeline (111) connected with the main machine or the water outlet pipeline (114) connected with the tail end, and a second pressure sensor (41) for acquiring the pressure of the outlet water is arranged on the water return pipeline (113) connected with the tail end or the water tank (3); the controller can judge whether the system has water leakage condition or not based on the water supplementing amount of the flow sensor (133), the water outlet pressure obtained by the first pressure sensor (31) and/or the water return pressure obtained by the second pressure sensor (41).

6. The hydraulic center of claim 5, wherein: a first temperature sensor for acquiring the temperature of the outlet water is arranged on the outlet water pipeline (114) at the connection tail end, and a second temperature sensor (42) for acquiring the temperature of the return water is arranged on the return water pipeline (113) or the water tank (3) at the connection tail end; the controller more accurately judges whether the system has water leakage conditions according to the historical data of the water outlet temperature and/or the water return temperature.

7. Hydraulic centre according to claim 5 or 6, characterized in that: a drain valve (33) is arranged at the bottom of the water tank (3), and a water supplementing valve (131) is arranged on the water supplementing pipeline (13); and when the controller judges that the water leakage condition exists based on the acquired data and logic reasoning, the water supplementing valve (131) is closed, the drain valve (33) is opened or the water supplementing valve (131) is closed, and sound and light alarm is given.

8. The hydraulic center of claim 1, wherein: the top of the water tank (3) is provided with an exhaust device (34), the exhaust device (34) is an automatic exhaust device or a spiral exhaust device, and the automatic exhaust device or the spiral exhaust device extends to the outer side of the water tank (3) and is communicated with the outside through an exhaust port (35).

9. The hydraulic center of claim 1, wherein: the water tank (3) is provided with a safety valve (44) and/or an electric heating device (37), and the water replenishing pipeline (13) is provided with a filter (134) and/or a check valve (132).

10. The hydraulic center of claim 1, wherein: the number of the water outlet pipelines (114) connected with the tail ends is two, and a control valve (115) is arranged on one water outlet pipeline (114) connected with the tail end.

11. The air-conditioning circulating water system comprises an air-conditioning main machine (2), a hydraulic center and a tail end; the method is characterized in that: a hydraulic center as claimed in any one of claims 1 to 9 of said hydraulic center; the water return pipeline (111) of the host is connected with the water outlet of the air-conditioning host (2), and the water outlet pipeline (112) of the host is connected with the water inlet of the air-conditioning host (2); a water return pipeline (113) connected with the tail end is connected with a water outlet at the tail end, and a water outlet pipeline (114) connected with the tail end is connected with a water inlet at the tail end; the water pump (51) is arranged on the air conditioner main machine (2), the hydraulic center or a system pipeline.

12. The air-conditioning circulating water system comprises an air-conditioning main machine (2), a hydraulic center and a tail end; the method is characterized in that: the hydraulic center of claim 10 of the hydraulic center; the water return pipeline (111) of the host is connected with the water outlet of the air-conditioning host (2), and the water outlet pipeline (112) of the host is connected with the water inlet of the air-conditioning host (2); a water return pipeline (113) connected with the tail end is connected with a water outlet at the tail end, and a water outlet pipeline (114) connected with the tail end is connected with a water inlet at the tail end; the water pump (51) is arranged on the air conditioner main machine (2), the hydraulic center or a system pipeline; when the tail end comprises a fan coil (52), a floor heater (53) and a heating sheet (54), the fan coil (52) is connected with the downstream of the water outlet pipeline (114) of one of the tail ends, and the floor heater (53) and the heating sheet (54) are connected in parallel with the downstream of the water outlet pipeline (114) of the other tail end.