Water chilling unit

Abstract

The invention provides a water chilling unit which comprises a compressor and a condenser, an outlet of the compressor communicates with an inlet of the condenser through a discharging pipeline, a rotating shaft and a valve plate with a counter weight are further arranged in the discharging pipeline, the rotating shaft is fixed to the inner wall of the discharging pipeline, the valve plate can rotate around the rotating shaft, and the counter weight is arranged on the valve plate. The rotatable stroke of the valve plate includes a first position where the valve plate swings downward to close the discharge duct, and a second position where the valve plate swings upward to a side away from the outlet of the compressor to open the discharge duct.

Description

Technical Field

[0001] The present application relates to the technical field of air conditioning, and in particular to a chiller. Background Art

[0002] When the chiller of the HVAC system is operating normally, the refrigerant is compressed by the compressor and discharged from the outlet of the compressor to the condenser through the discharge pipe. However, when the chiller stops unexpectedly, the uncondensed refrigerant may flow back into the compressor through the discharge pipe, which may pose a risk to the stability of the bearing components and rotating shaft of the compressor, thereby affecting the normal operation of the subsequent chiller.

[0003] The commonly used solution at present is to install a spring check valve in the discharge pipe, but the maximum opening of the spring check valve is usually 45 degrees, which may hinder the normal discharge of the compressor, causing a constant pressure drop (about 1-2psi) on both sides of the spring check valve, affecting the working efficiency of the chiller. In addition, since the spring is prone to aging and damage in the working environment at the outlet of the compressor, the reliability of the spring check valve is largely limited by the reliability of the spring, resulting in a decrease in the overall reliability of the chiller and an increase in maintenance costs. Summary of the invention

[0004] The present application aims to provide a chiller to at least solve or alleviate some of the problems existing in the prior art.

[0005] The present application provides a chiller, including a compressor and a condenser, wherein the outlet of the compressor and the inlet of the condenser are connected via a discharge pipe, and a rotating shaft and a valve plate with a counterweight are also provided in the discharge pipe, wherein the rotating shaft is fixed to the inner wall of the discharge pipe, and the valve plate can rotate around the rotating shaft, and the rotatable stroke of the valve plate includes: a first position of swinging down to close the discharge pipe, and a second position of swinging up to a side away from the outlet of the compressor to open the discharge pipe.

[0006] In an optional chiller, the compressor is arranged above the condenser, the discharge pipe has a main section extending in the vertical direction, and a bending section formed by lateral bending of the main section, the bending section is connected to the outlet located on the side of the compressor, and the rotating shaft and the valve plate are both arranged in the bending section.

[0007] In the chiller of the optional solution, the bending section also includes a horizontal section extending horizontally, and the rotating shaft and the valve plate are arranged in the horizontal section.

[0008] In the optional chiller, it also includes a limit portion formed by the inner wall of the discharge pipe extending radially inward, the limit portion is arranged on the side of the valve plate close to the outlet of the compressor, and the outer edge of the valve plate in the first position abuts against the inner edge of the limit portion.

[0009] In the chiller of the optional solution, the limiting portion is an integrally formed limiting plate having a complete outer edge and connected to the entire circumferential range of the inner wall of the discharge pipe.

[0010] In an optional chiller, the limiting portion includes a side plate and a bottom plate, the side plate is formed by radially extending inward from the side of the inner wall of the discharge pipe, and the bottom plate is formed by radially extending inward from the bottom of the inner wall of the discharge pipe, the top of the valve plate in the first position abuts against the inner wall of the discharge pipe, the side edge of the valve plate abuts against the side plate, and the lower edge of the valve plate abuts against the bottom plate.

[0011] In the chiller of the optional solution, the limiting portion is elastic.

[0012] In the chiller of the optional solution, the limiting portion is fixed to the inner wall of the discharge pipe by welding.

[0013] In the chiller of the optional solution, the limiting portion is inclined at an angle of 0-3° to the vertical direction.

[0014] In the optional chiller, the compressor is a centrifugal compressor.

[0015] In the chiller of the optional solution, the valve plate is driven down to the first position only by its own weight.

[0016] In the optional chiller, the weight of the counterweight is 1kg to 15kg.

[0017] According to the chiller of the present application, the valve plate with a counterweight is rotatably mounted on the rotating shaft. When the chiller is operating normally, the valve plate can rotate around the rotating shaft and swing up to the second position to maintain a larger opening, and according to the flow rate of the refrigerant, the valve plate can also spontaneously adjust the opening in response to the change in the flow rate of the refrigerant. When the chiller is shut down, the valve plate can swing down to the first position only under the drive of gravity, closing the discharge pipe to prevent the refrigerant from flowing back. Since there is no need to set up deformation driving components such as springs, and the closing of the valve plate is driven only by gravity, the reliability of the check valve is better, which can effectively reduce maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 shows an overall diagram of a chiller according to an embodiment of the present application;

[0019] Figure 2 A schematic cross-sectional view of a discharge pipe of a chiller according to an embodiment of the present application is shown;

[0020] Figure 3 A schematic structural diagram showing a valve plate in a bending section rotated to a first position according to an embodiment of the present application;

[0021] Figure 4A schematic structural diagram showing a valve plate in a bending section rotated to a second position according to an embodiment of the present application;

[0022] Figure 5 A right side view of a horizontal section of a discharge pipe of a chiller according to an embodiment of the present application is shown;

[0023] Figure 6 A left side view of a horizontal section of a discharge pipe of a chiller according to an embodiment of the present application is shown.

[0024] Figure 7 A right side view of a horizontal section of a discharge pipe of another chiller according to an embodiment of the present application is shown;

[0025] Figure 8 A left side view of a horizontal section of a discharge pipe of another chiller according to an embodiment of the present application is shown;

[0026] Fig. 9 A cross-sectional schematic diagram of a horizontal section of a discharge pipe of another chiller according to an embodiment of the present application is shown.

[0027] Figure markings: 1-compressor; 11-compressor outlet; 2-discharge pipe; 21-bending section; 21a-upper bending section; 21b-lower bending section; 22-main section; 3-condenser; 31-condenser inlet; 4-rotating shaft; 5-valve plate; 6-limiting part; 61-limiting plate; 62-side plate; 63-bottom plate. DETAILED DESCRIPTION

[0028] First of all, it should be noted that the composition, working principle, characteristics and advantages of the chiller according to the present application will be explained in an illustrative manner below, but it should be understood that all descriptions are given for illustrative purposes only and should not be construed as forming any limitation on the present application.

[0029] In addition, for any single technical feature described or implied in the embodiments mentioned in this document, or any single technical feature displayed or implied in the accompanying drawings, the present application still allows for continued arbitrary combination or deletion between these technical features (or their equivalents) without any technical obstacles, thereby obtaining more other embodiments of the present application that may not be directly mentioned in this document.

[0030] The term "swing" means to swing downward or sideways and downward along the direction of gravity, and "swing" means to swing upward or sideways and upward along the direction of gravity.

[0031] The valve plate has a "counterweight", which may mean using a valve plate with a heavier weight itself, or adding additional accessories such as a counterweight block or a counterweight plate to fix to the valve plate body. The weight of the counterweight can be selected as long as it can meet the purpose of normally opening the discharge pipe when the compressor is discharged, and stably closing the discharge pipe during backflow. In some embodiments, the weight of the counterweight can be 2kg to 15kg. When the valve plate within the counterweight range is closed, the force acting on the unit flow area is about 1-10psi, which can ensure the reliable closure of the discharge pipe. At the same time, when the refrigerant is flowing normally in the discharge pipe, the valve plate can also be quickly driven to open.

[0032] Figure 1 1 shows an overall diagram of a chiller according to an embodiment of the present application. Figure 1 As shown, the chiller according to the embodiment of the present application includes: a compressor 1 and a condenser 3 , and the outlet 11 of the compressor and the inlet 31 of the condenser are connected through a discharge pipe 2 .

[0033] The specific type of the compressor 1 is not limited here. In some embodiments, the compressor 1 may be a screw compressor, a centrifugal compressor, a scroll compressor, etc. Preferably, the compressor 1 is a centrifugal compressor.

[0034] The specific type of the condenser 3 is not limited here. In some embodiments, the condenser can be a water-cooled condenser, an air-cooled condenser, etc., preferably a water-cooled condenser.

[0035] Taking a centrifugal compressor as an example, a centrifugal compressor uses centrifugal force to drive the refrigerant from the low-pressure side of the system to the high-pressure side, and the high-pressure refrigerant is discharged from the outlet 11 of the compressor to the condenser 3 via the discharge pipe 2. When the exhaust pressure is too high, that is, the pressure in the condenser 3 or the discharge pipe 2 is too high, the centrifugal compressor may also stop pumping because it cannot overcome the pressure difference, and send a "surge" phenomenon. In addition, when the chiller is shut down, the high-temperature and high-pressure refrigerant may flow back along the discharge pipe 2, impacting the bearing components or rotating shaft of the centrifugal compressor, and affecting the subsequent normal operation of the chiller.

[0036] Figure 2 FIG. 2 shows a schematic cross-sectional view of a discharge pipe of a chiller according to an embodiment of the present application. Figure 2 As shown, the chiller of an embodiment of the present application also includes a rotating shaft 4 and a valve plate 5 with a counterweight arranged in the discharge pipe 2, wherein the rotating shaft 4 is fixed to the inner wall of the discharge pipe 2, and the valve plate 5 can rotate around the rotating shaft 4 under the action of gravity or a combination of gravity and other driving forces.

[0037] According to the chiller of the embodiment of the present application, the valve plate 5 with a counterweight is rotatably mounted on the rotating shaft 4.

[0038] When the chiller is operating normally, the compressor 1 continuously discharges refrigerant into the discharge pipe 2, and the high-temperature and high-pressure refrigerant continuously flows from the compressor outlet 11 to the condenser inlet 31. Driven by the refrigerant, the valve plate 5 swings upward to the side away from the compressor outlet 11. Since the spring is eliminated and there is no restriction on the spring elastic force, the valve plate 5 can rotate to the second position and maintain a large opening under the drive of the pressure difference on both sides. And according to the flow rate of the refrigerant, the driving force of the refrigerant on the valve plate 5 will also change accordingly, so that the opening of the valve plate 5 can spontaneously respond to the change in the flow rate of the refrigerant, avoiding obstruction to the flow of the refrigerant in the discharge channel, resulting in excessive pressure drop at the compressor outlet 11 and loss of pressure head.

[0039] When the chiller is shut down normally, that is, when there is no refrigerant flowing in the discharge pipe 2, the valve plate 5 can swing down to the first position only by its own gravity to close the discharge pipe 2 and prevent the high-temperature and high-pressure refrigerant from flowing back. In the event of an unexpected shutdown, if a certain amount of refrigerator backflow occurs, the refrigerator that flows back can also accelerate the swing down of the valve plate 5, thereby reducing the amount of backflow as much as possible.

[0040] In some embodiments of the present application, the valve plate 5 and the rotating shaft 4 of the chiller can maintain a relatively large opening when the chiller is operating normally, and can adjust the opening automatically in response to changes in the flow rate of the refrigerant. In addition, since there is no need to set elastic elements such as springs, and the closing of the valve plate 5 is driven only by gravity, the reliability of the check valve is better, and the maintenance cost can be effectively reduced.

[0041] The valve plate 5 can be rotated and swung down to the first position where the valve plate extends in the direction of gravity, or can be swung down to the first position inclined with respect to the direction of gravity, as long as the valve plate 5 can stop swinging down at this position and close the discharge pipe 2. For example, the valve plate 5 can be inclined at an angle of 0-3° with respect to the direction of gravity. Setting a certain inclination angle can utilize the gravity of the valve plate 5 itself, increase the stress between the valve plate 5 and the limiting portion 6, and increase the reliability of the valve plate 5 closing the discharge pipe 2 when the valve plate 5 is in the first position.

[0042] In the chiller of the embodiment of the present application, the compressor 1 and the condenser 3 can be arranged according to the actual use environment. For example, the compressor 1 and the condenser 3 can be stacked in the height direction with at least partial overlap, the outlet 11 of the compressor and the inlet 31 of the condenser can be arranged on the same side, and the two ends of the discharge pipe 2 are bent to connect the outlet 11 of the compressor and the inlet 31 of the condenser respectively, so that the internal structure of the chiller is more compact.

[0043] In some embodiments, the bending section 21 further includes a horizontal section extending horizontally, and the rotating shaft 4 and the valve plate 5 are arranged in the horizontal section of the discharge pipe 2. The valve plate 5 can be quickly lowered in the horizontal discharge pipe 2 to abut against the bottom of the inner wall of the discharge pipe 2, and can also be opened to a position close to, equal to, or even exceeding 90° to increase the maximum opening of the discharge pipe 2.

[0044] In other embodiments, the compressor 1 is arranged above the condenser 3, and the discharge pipe 2 has a main section 22 extending in the vertical direction, and a bent section 21 formed by the lateral bending of the main section 22. Figure 1 From the above, the upper and lower parts of the discharge pipe 2 are both formed with bent sections 21, wherein the upper bent section 21a is connected to the outlet located on the side of the compressor 1, and the lower bent section 21b is connected to the inlet located on the side of the condenser 3. The arrangement of stacking the compressor 1 and the condenser 3 up and down can make the internal structure of the chiller more compact.

[0045] Hereinafter, the assembly structure of the valve plate 5 and the rotating shaft 4 in the bending section 21 of the discharge pipe 2 will be described by taking the case where the valve plate 5 and the rotating shaft 4 are arranged in the upper bending section 21 a as an example. Figure 3 A schematic structural diagram is shown in which the valve plate 5 in the bending section 21 according to an embodiment of the present application rotates to the first position. Figure 4 A schematic structural diagram is shown in which the valve plate 5 in the bending section 21 according to an embodiment of the present application rotates to the second position.

[0046] Combination Figure 3 and Figure 4 As shown in FIG. 2 , in the bending section 21 , the rotating shaft 4 is fixed to the top of the inner wall of the bending section 21 , and the valve plate 5 is arranged below the rotating shaft 4 and can rotate around the rotating shaft 4 .

[0047] When the compressor is not working and there is no refrigerant flowing in the discharge pipe 2, the valve plate 5 rotates and swings down to the first position driven by its own gravity. The height of the valve plate 5 is greater than the diameter of the discharge pipe 2. After the valve plate 5 swings down, the bottom end of the valve plate 5 can directly abut against the bent lower surface of the inner wall of the bending section 21, thereby closing the discharge pipe 2 and blocking the refrigerant refluxed from the condenser 3 when necessary. When the compressor is working, the refrigerant discharged by the compressor 1 is discharged from the discharge pipe 2 to the condenser 3. Driven by the pressure difference and the flowing refrigerant, the valve plate 5 swings to the second position on the side away from the outlet 11 of the compressor, thereby opening the discharge pipe 2. When the pressure difference is large enough, the valve plate 5 can be opened until it abuts against the top of the inner wall of the bending section 21 of the discharge pipe 2, thereby reducing the obstruction to the circulation of the refrigerant in the discharge pipe 2 and keeping the refrigerant in the discharge pipe 2 flowing smoothly.

[0048] The chiller also includes a limit portion 6 formed by the inner wall of the discharge pipe 2 extending radially inwardly, and the limit portion 6 is arranged on the side of the valve plate 5 close to the outlet 11 of the compressor, and the outer edge of the valve plate 5 in the first position abuts against the inner edge of the limit portion 6. The setting that the limit portion 6 abuts against the valve plate 5 can ensure the reliability of the valve plate 5 closing the discharge pipe 2 in the first position, and prevent the valve plate 5 from swinging in the opposite direction (i.e., swinging to the side close to the compressor outlet) under the impact of the refluxed refrigerant.

[0049] The limiting portion 6 can be directly formed by the inner wall protrusion of the discharge pipe 2 (such as Figure 3 , 4 The structure shown in the figure) can also be fixedly mounted on the inner wall of the discharge pipe 2, or, in some embodiments, the inner diameter of the discharge pipe 2 on the side of the valve plate 5 close to the outlet 11 of the compressor can be slightly reduced (such as Figure 2 As shown in ), a limiting portion 6 is formed so that when the valve plate swings down to close, the outer edge of the valve plate can abut against the discharge pipe 2 with a small inner diameter all around. The above are all applicable to the chiller of the present application.

[0050] In some embodiments, the discharge pipe 2 and the limiting portion 6 are both made of metal, and the limiting portion 6 is welded and fixed to the inner wall of the discharge pipe 2 , which can increase the reliability and firmness of the limiting portion 6 .

[0051] In some embodiments of the present application, the limiting portion 6 may be an integrally formed limiting plate 61 having a complete outer edge and connected to the entire circumferential range of the inner wall of the discharge pipe 2. Thus, when the valve plate 5 is in the first position, the outer edge of the entire circumference of the valve plate 5 may abut against the inner edge of the limiting plate 61, thereby being able to more tightly close the discharge pipe 2 and prevent a small amount of refrigerant from flowing back through the gap between the valve plate 5 and the limiting portion 6.

[0052] In some other embodiments of the present application, the limiting portion 6 may not have a complete outer edge, but one or more limiting plates 61 are arranged at intervals in the circumferential range of the inner wall of the discharge pipe 2. Correspondingly, the outer edge portion of the valve plate 5 contacts the inner wall of the discharge pipe 2, and the other portion abuts against the limiting plate 61. Since the limiting plate 61 is not connected to the inner wall of the discharge pipe 2 around the entire circumference, it has less impact on the flow of refrigerant in the discharge pipe 2, and the maximum flow in the discharge pipe 2 is larger, thereby improving the working efficiency of the chiller.

[0053] Figure 5-Figure 9 The assembly structure of two valve plates 5 and a rotating shaft 4 of a chiller according to the present application in a discharge pipe is shown.

[0054] Figure 5 and Figure 6The right side view and the left side view respectively show a horizontal section of a discharge pipe of a chiller according to an embodiment of the present application. Figure 5 and Figure 6 From the perspective of the embodiment, the rotating shaft 4 is fixed to the top of the inner wall of the discharge pipe 2, the upper edge of the valve plate 5 is connected to the rotating shaft 4, the two side edges of the valve plate 5 are formed into parallel straight outer edges, and the lower edge of the valve plate 5 matches the shape of the inner wall of the bottom of the pipe. Therefore, in the process of the valve plate 5 rotating and swinging from the first position to the second position, since the bottom of the valve plate 5 swings upward, and the upper edge and the side outer edge of the valve plate 5 do not contact the inner wall of the pipe, it is possible to ensure the flow area while not scraping the inner wall of the discharge pipe 2.

[0055] Correspondingly, refer to Figure 6 The limiting portion 6 is formed as an integrally formed limiting plate 61, the outer edge of which matches the circumferential shape of the inner wall of the discharge pipe 2, and can be fixedly installed (for example, welded) with the inner wall of the discharge pipe 2 in the entire circumferential range, and the inner edges of the side, bottom and top of the limiting plate 61 enclose a flow opening. Among them, the inner edge of the limiting plate 61 on the side abuts against the parallel straight outer edges on both sides of the valve plate 5, the limiting plate 61 on the top corresponds to the rotating shaft 4, and the lower edge of the top limiting plate 61 abuts against the upper edge of the valve plate 5, and the bottom limiting plate 61 abuts against the lower edge of the valve plate 5, so that the valve plate 5 can close the discharge pipe 2 in the first position by completely covering the flow opening. Since the outer edges of the valve plate 5 abut against the limiting portion 6, the sealing performance of the valve plate 5 to the closed structure of the discharge pipe 2 is better, more firm and reliable.

[0056] Another example, Figure 7 and Figure 8 The right view and left view of the horizontal section of the discharge pipe of another chiller according to an embodiment of the present application are respectively shown. Fig. 9 A cross-sectional schematic diagram of a horizontal section of a discharge pipe of another chiller according to an embodiment of the present application is shown. Figure 7-Figure 9 From the perspective of the embodiment, the rotating shaft 4 is fixed to the top of the inner wall of the discharge pipe 2, the two side edges of the valve plate 5 are formed into parallel straight outer edges, and the upper and lower edges of the valve plate 5 match the inner wall shape of the bottom of the pipe, so that the top and bottom of the valve plate 5 in the first position (the position of the solid line valve plate 5 in the figure) are both in contact with the inner wall of the discharge pipe 2, and the rotating shaft 4 is connected to the middle of the valve plate 5 (excluding the upper and lower edges of the valve plate 5). In the process of the valve plate 5 rotating and swinging from the first position to the second position (the position of the dotted line valve plate 5 in the figure), the outer edges of the side of the valve plate 5 do not contact the inner wall of the pipe, so that a larger flow area can be obtained while reducing the scratching with the inner wall of the discharge pipe 2.

[0057] Correspondingly, the limiting portion 6 has a side plate 62 and a bottom plate 63. The side plate 62 is formed by the radially inward extension of the side portion of the inner wall of the discharge pipe 2, and the bottom plate 63 is formed by the radially inward extension of the bottom portion of the inner wall of the discharge pipe 2. The inner edges of the side plate 62 and the bottom plate 63 and the inner wall of the discharge pipe 2 are enclosed together to form a larger flow opening. Among them, the inner edge of the side plate 62 abuts against the parallel straight outer edges on both sides of the valve plate 5, and the bottom plate 63 abuts against the lower edge of the valve plate 5, so that the valve plate 5 can abut against the limiting portion 6 in the first position to close the discharge pipe 2. When the valve plate 5 rotates and swings to the second position, because the limiting portion 6 is larger than the valve plate 5, the valve plate 5 can be closed by the limiting portion 6. Figure 5 , Figure 6 The area of ​​the embodiment is smaller, and the flow opening area for the refrigerant to circulate is larger, which is beneficial to improving the working efficiency of the chiller.

[0058] The limiting portion 6 of the chiller of some embodiments of the present application may be elastic, so that when the lower edge of the valve plate 5 abuts against the limiting portion 6, it can be elastically pressed against the limiting portion 6, thereby improving the sealing performance and also having a certain buffering effect on the impact of the returning refrigerant.

[0059] In some embodiments of the present application, the rotating shaft 4 and the valve plate 5 are both arranged close to the outlet of the compressor 1, so that the distance between the one-way valve composed of the rotating shaft 4 and the valve plate 5 and the outlet of the compressor 1 is minimized, thereby minimizing the gas capacity in this section of the pipeline and reducing the possibility of reversal of the compressor caused by backflow.

[0060] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A chiller, characterized in that: include: compressor; Condenser; a discharge pipe connecting the outlet of the compressor and the inlet of the condenser; A rotating shaft fixed to the inner wall of the discharge pipe; The valve plate with a counterweight can rotate around the rotating shaft, and the rotatable stroke of the valve plate includes: a first position of swinging down to close the discharge pipe, and a second position of swinging up to a side away from the outlet of the compressor to open the discharge pipe.

2. The water chiller according to claim 1, characterized in that: The compressor is arranged above the condenser, the discharge pipe has a main section extending in the vertical direction, and a bending section formed by lateral bending of the main section, the bending section is connected to the outlet located on the side of the compressor, and the rotating shaft and the valve plate are both arranged in the bending section.

3. The chiller according to claim 2, characterized in that: The bending section further comprises a horizontal section extending horizontally, and the rotating shaft and the valve plate are arranged in the horizontal section.

4. The water chiller according to claim 2 or 3, characterized in that: It also includes a limiting portion formed by the inner wall of the discharge pipe extending radially inward, the limiting portion is arranged on a side of the valve plate close to the outlet of the compressor, and the outer edge of the valve plate in the first position abuts against the inner edge of the limiting portion.

5. The water chiller according to claim 4, characterized in that: The limiting portion is an integrally formed limiting plate having a complete outer edge and connected to the entire circumferential range of the inner wall of the discharge pipe.

6. The water chiller according to claim 4, characterized in that: The limiting portion includes a side plate and a bottom plate, the side plate is formed by radially extending inward from the side of the inner wall of the discharge pipe, and the bottom plate is formed by radially extending inward from the bottom of the inner wall of the discharge pipe, the top of the valve plate in the first position abuts against the inner wall of the discharge pipe, the side edge of the valve plate abuts against the side plate, and the lower edge of the valve plate abuts against the bottom plate.

7. The water chiller according to claim 4, characterized in that: The limiting portion is elastic.

8. The water chiller according to claim 4, characterized in that: The limiting portion is fixed to the inner wall of the discharge pipe by welding.

9. The water chiller according to claim 4, characterized in that: The limiting portion is inclined at an angle of 0-3° to the vertical direction.

10. The water chiller according to claim 1, characterized in that: The compressor is a centrifugal compressor.

11. The water chiller according to claim 1, characterized in that: The valve plate swings down to the first position only by its own weight providing driving force.

12. The water chiller according to claim 1, characterized in that: The weight of the counterweight is 1kg to 15kg.

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