Air supply device and heat exchange system

Abstract

The utility model provides an air supply device and a heat exchange system. The gas supply device comprises a shell; a piston; an air inlet and an air outlet are formed in the air supply cavity, the air inlet is communicated with an air source, and the air outlet is communicated with the air bearing. According to the air supply device and the heat exchange system provided by the utility model, when a heat pump system stops working due to majeure factors (such as sudden power failure and unstable voltage), the air supply cavity supplies air to the air bearing for a certain time by utilizing the pressure in the pressure cavity and the movement of the piston; therefore, in the process that the rotating shaft of the compressor stops rotating, the gas bearing can obtain gas all the time to support the rotating shaft, and the problem of dry friction between the rotating shaft and the gas bearing due to the fact that the gas bearing cannot supply gas in the prior art is effectively solved. The situation that a compressor rotating shaft or a gas bearing is damaged is effectively avoided, and then the reliability of a heat exchange system is guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of heat exchange devices, in particular to a gas supply device and a heat exchange system. Background Art

[0002] In the field of centrifugal magnetic levitation chillers, due to the unique structure of the magnetic levitation centrifugal compressor, when the compressor is in normal operation, the unit needs to supply gas to its gas bearings to suspend the shaft in the air for rotation to achieve the minimum energy consumption. However, the power drive of the gas supply system relies on an air pump, and the air pump is driven by electricity; when the power is stable, the compressor and the electric air pump can be normally powered, and the unit can operate normally; but when force majeure factors occur (such as sudden power outage, unstable voltage, etc.), the heat pump system will stop working, the compressor and the electric air pump will be forced to stop power supply, and the air supply of the air pump will fail after the power is cut off, and it will be unable to continue supplying gas to the gas bearings; after the power of the compressor is cut off, the rotating shaft of the compressor will lose power, but the rotating shaft of the compressor will still rotate inertially for a few minutes until it completely stops. During the process of the rotating shaft stopping, the gas bearings do not have enough gas supply to suspend the shaft, and the rotating shaft of the compressor and the gas bearings will form dry friction and be damaged, resulting in the problems that the compressor is easily damaged and cannot work reliably. Content of the Utility Model

[0003] In order to solve the technical problem that the gas bearings cannot supply gas reliably and cause damage to the compressor when the power supply is abnormal in the prior art, a gas supply device and a heat exchange system are provided, which use the pressure in the pressure chamber to drive the piston to move to ensure the gas supply effect.

[0004] A gas supply device includes:

[0005] A housing;

[0006] A piston, which is movably arranged in the housing, and the piston divides the interior of the housing into a gas supply chamber and a pressure chamber with variable volume;

[0007] The gas supply chamber is provided with an air inlet and an air outlet, the air inlet is communicated with a gas source, and the air outlet is communicated with the gas bearings;

[0008] The pressure chamber is provided with a pressure inlet and a pressure outlet, the pressure inlet is communicated with a pressure supply structure, and the pressure outlet is communicated with the outside of the pressure chamber.

[0009] The gas supply device is applied to a heat exchange system, the heat exchange system includes a condenser and an evaporator, the pressure inlet is communicated with the condenser, and the pressure outlet is communicated with the evaporator.

[0010] The condenser has a liquid refrigerant outlet, and the liquid refrigerant outlet is communicated with the pressure inlet.

[0011] The condenser includes a shell-and-tube heat exchanger.

[0012] A normally open solenoid valve is provided at the pressure inlet; and / or, a normally closed solenoid valve is provided at the pressure outlet.

[0013] A sealing structure is provided between the piston and the inner wall of the housing.

[0014] The air supply device further includes a first limiting structure and a second limiting structure. The first limiting structure is located on one side of the pressure inlet close to the air outlet, and the second limiting structure is located on one side of the air outlet close to the pressure inlet. The piston is movably arranged between the first limiting structure and the second limiting structure.

[0015] The air supply device further includes a pressurizing structure. The inlet of the pressurizing structure is communicated with the air source, and the outlet of the pressurizing structure is communicated with the air inlet.

[0016] The number of the air outlets is at least two, and all the air outlets are annularly distributed with the axis of the housing as the axis. The air inlet is located on the end face of the air supply cavity.

[0017] The air supply device further includes an air outlet pipe. The air outlet pipe is arranged in the housing, and one end of the air outlet pipe forms the air outlet on the housing, and the other end faces the central area of the air supply cavity.

[0018] A heat exchange system includes the above-mentioned air supply device.

[0019] When force majeure factors (such as sudden power outage, unstable voltage, etc.) cause the heat pump system to stop working, the air supply device and heat exchange system provided by the present utility model utilize the pressure in the pressure cavity and the movement of the piston to supply air to the gas bearing in the air supply cavity for a certain period of time, so as to ensure that the gas bearing can always obtain gas during the process of the rotation shaft of the compressor stopping rotating, thereby ensuring the support for the rotation shaft, effectively avoiding the problem of dry friction between the rotation shaft and the gas bearing caused by the inability to supply air to the gas bearing in the prior art, effectively avoiding the situation that the rotation shaft of the compressor or the gas bearing is damaged, and further ensuring the reliability of the heat exchange system. Description of the Drawings

[0020] Figure 1 is a schematic structural diagram of the air supply device provided by an embodiment of the present utility model;

[0021] Figure 2 is a schematic structural diagram of the air supply device provided by an embodiment of the present utility model during normal power supply;

[0022] Figure 3Schematic diagram of the structure of the gas supply device provided by the embodiment of the present utility model when power is off;

[0023] Figure 4 Schematic diagram of the structure of the gas supply device provided by the embodiment of the present utility model for supplying gas to a gas bearing;

[0024] In the figure:

[0025] 1. Housing; 2. Piston; 11. Gas supply chamber; 12. Pressure chamber; 13. Air inlet; 14. Air outlet; 15. Pressure inlet; 16. Pressure outlet; 3. Gas bearing; 4. Normally open solenoid valve; 5. Normally closed solenoid valve; 17. First limit structure; 18. Second limit structure; 6. Pressurizing structure. Detailed implementation manners

[0026] In order to make the objectives, technical solutions and advantages of the present utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.

[0027] In order to enable those skilled in the art to better understand the solution of the present utility model, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0028] It should be noted that the terms "first", "second", etc. in the specification and claims of the present utility model and the above-mentioned drawings are used to distinguish similar objects and do not necessarily need to describe a specific order or sequence. It should be understood that such terms can be interchanged under appropriate circumstances for the embodiments of the present utility model described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0029] It should be noted that in the description of the present utility model, the terms indicating the direction or positional relationship such as "upper", "lower", "left", "right", "inner", "outer", etc. are based on the direction or positional relationship shown in the drawings. This is only for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0030] In addition, it should also be noted that in the description of the present utility model, unless otherwise clearly specified and limited, the terms "installation", "setting", "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and can also be the communication inside two elements. For those skilled in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0031] In the field of centrifugal air suspension chillers, due to the unique structure of the air suspension centrifugal compressor, when the compressor is in normal operation, the unit needs to supply gas to its gas bearings to suspend the shaft in the air for rotation to achieve the minimum energy consumption. However, the power drive of the gas supply system relies on an air pump, and the air pump is electrically driven; when the power is stable, the compressor and the electric air pump can be normally powered, and the unit can operate normally; but when force majeure factors occur (such as sudden power outage, unstable voltage, etc.), the heat pump system will stop working, the compressor and the electric air pump will be forced to stop power supply. After the air pump loses power, the air supply of the air pump will fail and it cannot continue to supply gas to the gas bearings; after the compressor loses power, the rotating shaft of the compressor will lose power, but the rotating shaft of the compressor will still rotate inertially for several minutes until it completely stops. During the process of the rotating shaft stopping, the gas bearings do not have enough gas supply to suspend the shaft, and the rotating shaft of the compressor and the gas bearings will form dry friction and be damaged, resulting in the problems that the compressor is easily damaged and cannot work reliably. For this reason, the present application provides a Figures 1 to 4The shown air supply device includes: a housing 1; a piston 2, which is movably arranged inside the housing 1, and the piston 2 divides the interior of the housing 1 into a variable-volume air supply chamber 11 and a pressure chamber 12; an air inlet 13 and an air outlet 14 are provided on the air supply chamber 11, the air inlet 13 is communicated with an air source, and the air outlet 14 is communicated with a gas bearing 3; a pressure inlet 15 and a pressure outlet 16 are provided on the pressure chamber 12, the pressure inlet 15 is communicated with a pressure supply structure, and the pressure outlet 16 is communicated with the outside of the pressure chamber 12. When the heat exchange system where the air supply device is located is powered on normally, the air supply device can normally supply gas to the gas bearing 3. The gas can enter the air supply chamber 11 through the air inlet 13 and be sent to the gas bearing 3 through the air outlet 14. Since the gas at the air inlet 13 has pressure, the gas in the air supply chamber 11 will push the piston 2 to move. At this time, the volume of the air supply chamber 11 increases, and correspondingly, the volume of the pressure chamber 12 decreases, and a certain amount of gas can be stored in the air supply chamber 11; when force majeure factors (such as sudden power outage, unstable voltage, etc.) cause the heat pump system to stop working, the gas supply at the air inlet 13 of the air supply device stops, and the pressure in the pressure chamber 12 and the movement of the piston 2 are used to supply gas to the gas bearing 3 by the air supply chamber 11 for a certain period of time. At this time, the pressure in the pressure chamber 12 and the movement of the piston 2 can make the gas stored in the air supply chamber 11 continue to be sent to the gas bearing 3 through the air outlet 14, so as to ensure that during the process of the rotating shaft of the compressor stopping rotating, the gas bearing 3 can always obtain gas to ensure the support of the rotating shaft, effectively avoiding the problem of dry friction between the rotating shaft and the gas bearing 3 in the prior art, effectively avoiding the damage of the rotating shaft of the compressor or the gas bearing 3, and further ensuring the reliability of the heat exchange system. When the air supply device and the heat exchange system are powered on again, the air inlet 13 continuously sends gas into the air supply chamber 11, and the air supply chamber 11 starts to supply power to the gas bearing 3 through the air outlet 14. At the same time, the gas in the air supply chamber 11 will drive the piston 2 to move, so that the volume of the air supply chamber 11 increases and part of the gas is stored again, preparing for the next unexpected situation.

[0032] Preferably, the piston 2 moves along the height direction of the housing 1, and the air supply chamber 11 is located below the piston, and the pressure chamber 12 is located above the piston 2. When an unexpected situation occurs, the self-weight of the piston 2 can also drive the piston to move downward. At this time, the driving force for the piston 2 to move downward is the pressure at the pressure inlet 15 and the self-weight of the piston 2, ensuring the reliable movement of the piston 2 and further ensuring the reliable gas supply of the air supply chamber 11.

[0033] As an implementation manner, the air supply device is applied to a heat exchange system, which includes a condenser and an evaporator. The pressure inlet 15 is communicated with the condenser, and the pressure outlet 16 is communicated with the evaporator. When the heat exchange system suddenly loses power, there is still heat exchange working medium in the condenser. Therefore, the heat exchange working medium in the condenser can be sent into the pressure chamber 12, and the pressure generated by this part of the heat exchange working medium is used to push the piston 2 to move, so that the piston 2 can squeeze the gas in the air supply chamber 11 to be discharged from the air outlet 14, ensuring the gas pressure sent from the air outlet 14 to the gas bearing 3, ensuring the support for the rotating shaft, effectively avoiding the problem of dry friction between the rotating shaft and the gas bearing 3 caused by the inability to supply air to the gas bearing 3 in the prior art, effectively avoiding the damage of the compressor rotating shaft or the gas bearing 3, and further ensuring the reliability of the heat exchange system.

[0034] Moreover, there are impurities in the refrigerant in the heat exchange system. When the impurities enter the gas bearing 3, they will cause wear and damage to the gas bearing 3. In this application, the piston 2 is used to separate the refrigerant in the pressure chamber 12 from the gas in the air supply chamber 11, which can prevent impurities from entering the gas bearing 3 and ensure the reliability of the gas bearing 3. Moreover, even when the power is off, the refrigerant in the condenser drives the piston 2 to move downward as a power source to provide air supply power for the air supply chamber 11. At this time, due to the isolation effect of the piston 2, the gas sent from the air supply chamber 11 to the gas bearing 3 will not be mixed with other impurities. Therefore, the gas sent from the air supply chamber 11 to the gas bearing 3 is still pure gas, which is beneficial to ensuring the purity of the air supply and further ensuring the reliable operation of the gas bearing 3.

[0035] In addition, small liquid droplets are mixed in the gaseous refrigerant obtained from the condenser, and the small liquid droplets are not evenly distributed. When the small liquid droplets encounter the running high-temperature gas suspension bearing, they will instantly vaporize from the liquid state to the gaseous state, forming local detonation (similar to the explosion of firecrackers), which will cause the running accuracy of the gas bearing 3 to be low. In this application, the piston 2 is used to separate the refrigerant in the pressure chamber 12 from the gas in the air supply chamber 11, which can prevent small liquid droplets from entering the gas bearing 3 and ensure the reliability of the gas bearing 3. Moreover, even when the power is off, the refrigerant in the condenser drives the piston 2 to move downward as a power source to provide air supply power for the air supply chamber 11. At this time, due to the isolation effect of the piston 2, the gas sent from the air supply chamber 11 to the gas bearing 3 will not be mixed with small liquid droplets. Therefore, the gas sent from the air supply chamber 11 to the gas bearing 3 is still clean gas, which is beneficial to ensuring the purity of the air supply and further ensuring the reliable operation of the gas bearing 3.

[0036] In a heat exchange system, a condenser is connected to a compressor. The exhaust gas of the compressor can be sent into the condenser. However, the exhaust gas of the compressor will cause pressure fluctuations in the condenser. At this time, if the condenser is directly used as a gas source or the exhaust gas pressure of the compressor is directly used as the supply gas, since the supply gas obtained from both of these will be affected by the disturbed air flow of the compressor exhaust, the gas is actually fluctuating and not stable. If it is directly used to supply gas to the gas bearing 3, it will result in a low operating accuracy of the gas bearing 3. The unstable supply gas is also likely to cause the rotating shaft of the compressor to run with jumps, easily causing the problem of shaft collision. In this application, the piston 2 is used to separate the refrigerant in the pressure chamber 12 and the gas in the supply gas chamber 11. When the refrigerant of the condenser enters the pressure chamber 12, it will provide a driving force for the movement of the piston 2. At this time, the pressure fluctuations of the refrigerant will be offset by the movement of the piston 2, which can not only ensure the reliable supply of gas to the gas bearing 3, but also avoid the influence of the pressure fluctuations in the condenser on the working reliability of the gas bearing 3, ensuring the working reliability of the gas bearing 3.

[0037] Preferably, the condenser has a liquid refrigerant outlet, and the liquid refrigerant outlet is connected to the pressure inlet 15. Introducing the liquid refrigerant in the condenser into the pressure chamber 12, the liquid refrigerant is located at the bottom of the condenser and will not be affected by the exhaust gas of the compressor connected to the condenser, which can avoid the problem that the pressure in the condenser is disturbed by the compressor exhaust, ensure the smooth movement of the piston 2, and thus ensure the smooth and reliable gas supply of the gas supply device. Optionally, the condenser includes a shell-and-tube heat exchanger, and the liquid refrigerant outlet is located below the liquid level of the shell-and-tube heat exchanger.

[0038] Among them, a normally open solenoid valve 4 is provided at the pressure inlet 15. When the gas supply device and the heat exchange system where it is located are normally powered, the normally open solenoid valve 4 is energized and in a closed state. At this time, the liquid refrigerant of the condenser will not flow into the pressure chamber 12, and the refrigerant in the condenser can circulate and exchange heat in the heat exchange system. When the gas supply device and the heat exchange system where it is located suddenly lose power, the normally open solenoid valve 4 loses power and opens, and the liquid refrigerant in the condenser will enter the pressure chamber 12 to squeeze the piston 2, thereby driving the piston 2 to squeeze the gas in the supply gas chamber 11 to be discharged from the air outlet 14, maintaining the gas supply to the gas bearing 3.

[0039] A normally closed solenoid valve 5 is provided at the pressure outlet 16. When the air supply device and the heat exchange system where it is located are normally powered, the normally closed solenoid valve 5 is energized and in an open state. At this time, the gas entering from the air inlet 13 can smoothly drive the piston 2 to move after entering the air supply chamber 11. The volume of the pressure chamber 12 decreases due to the movement of the piston 2, and the gas in the pressure chamber 12 can enter the evaporator through the pressure outlet 16, reducing the difficulty of the piston 2 moving. When the air supply device and the heat exchange system where it is located suddenly lose power, the normally closed solenoid valve 5 loses power and closes. At the same time, the liquid refrigerant in the condenser enters the pressure chamber 12 and does not flow into the evaporator through the pressure outlet 16, ensuring the reliability of the liquid refrigerant driving the piston 2 to move. The piston 2 squeezes the gas in the air supply chamber 11 and discharges it from the air outlet 14, maintaining the air supply to the gas bearing 3.

[0040] A sealing structure is provided between the piston 2 and the inner wall of the housing 1. The sealing structure is used to prevent the pressure chamber 12 and the air supply chamber 11 from communicating, ensuring the air supply reliability of the air supply device. At the same time, it can also prevent the refrigerant in the pressure chamber 12 from mixing with the gas in the air supply chamber 11 and affecting the cleanliness of the refrigerant working medium in the heat exchange system, ensuring the reliable operation of the heat exchange system.

[0041] The air supply device further includes a first limiting structure 17 and a second limiting structure 18. The first limiting structure 17 is located on the side of the pressure inlet 15 close to the air outlet 14, and the second limiting structure 18 is located on the side of the air outlet 14 close to the pressure inlet 15. The piston 2 is movably arranged between the first limiting structure 17 and the second limiting structure 18. The first limiting structure 17 and the second limiting structure 18 are used to limit the movement range of the piston 2, preventing the piston 2 from blocking the pressure inlet 15 or the air outlet 14, and ensuring the reliability of the air supply device.

[0042] The air supply device further includes a pressurizing structure 6. The inlet of the pressurizing structure 6 is communicated with the gas source, and the outlet of the pressurizing structure 6 is communicated with the air inlet 13. The pressurizing structure 6 is used to pressurize the gas sent into the air supply chamber 11, ensuring that the pressure in the air supply chamber 11 can meet the requirements of the gas bearing 3, and also ensuring that the pressure in the air supply chamber 11 can reliably drive the piston 2 to move, ensuring the working reliability of the air supply device. At this time, the gas source can provide non-pressure gas. The pressurizing structure 6 can obtain non-pressure gas from the gas source, form pressure gas after being pressurized by the pressurizing structure 6, and then send it to the gas bearing 3 through the air supply chamber 11, reducing the requirements of the air supply device for the gas source and increasing the applicable range of the air supply device.

[0043] The number of the air outlets 14 is at least two, and all the air outlets 14 are annularly distributed with the axis of the housing 1 as the axis. The air inlet 13 is located on the end face of the air supply chamber 11. The use of multiple air outlets 14 can supply air to multiple gas bearings 3 simultaneously. By arranging the air inlet 13 on the end face of the air supply chamber 11, the distance from the air inlet 13 to each air outlet 14 is basically equal, so as to ensure that the gas pressure at each air outlet 14 is basically equal, ensuring that all gas bearings 3 can receive the same pressure gas for normal operation. Moreover, the air inlet 13 does not point to any one of the air outlets 14, avoiding the gas from the air inlet 13 blowing directly into the air outlet 14, and reducing the fluctuation and impact of the air flow.

[0044] As an implementation manner, the air supply device further includes an air outlet pipe, which is arranged in the housing 1. One end of the air outlet pipe forms the air outlet 14 on the housing 1, and the other end faces the central area of the air supply chamber 11. The air outlet pipe further avoids the gas from the air inlet 13 blowing directly into the air outlet 14, reducing the fluctuation and impact of the air flow. At the same time, the air outlet pipe forms a protrusion on the inner wall of the housing 1, and this protrusion can limit the piston 2, that is, at this time, the air outlet pipe constitutes the second limiting structure 18. Preferably, the end of the air outlet pipe facing the inside of the housing 1 is bent, so that the gas sent into the air inlet 13 needs to flow through a baffle before flowing into the air outlet pipe, further avoiding the gas from the air inlet 13 blowing directly into the air outlet 14, and reducing the fluctuation and impact of the air flow.

[0045] A heat exchange system includes the above-mentioned air supply device.

[0046] The above embodiments only represent several implementation manners of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention should be subject to the appended claims.

Claims

1. A gas supply device, characterized in that: include: Housing (1); A piston (2), the piston (2) being movably disposed in the housing (1), and the piston (2) dividing the interior of the housing (1) into an air supply chamber (11) and a pressure chamber (12) with variable volumes; The air supply cavity (11) is provided with an air inlet (13) and an air outlet (14), the air inlet (13) is connected to an air source, and the air outlet (14) is connected to a gas bearing (3); The pressure chamber (12) is provided with a pressure inlet (15) and a pressure outlet (16); the pressure inlet (15) is connected to a pressure supply structure, and the pressure outlet (16) is connected to the outside of the pressure chamber (12).

2. The gas supply device according to claim 1, characterized in that: The air supply device is applied to a heat exchange system, wherein the heat exchange system comprises a condenser and an evaporator, wherein the pressure inlet (15) is connected to the condenser, and the pressure outlet (16) is connected to the evaporator.

3. The gas supply device according to claim 2, characterized in that: The condenser has a liquid refrigerant outlet, and the liquid refrigerant outlet is connected to the pressure inlet (15).

4. The air supply device according to claim 2, characterized in that: The condenser comprises a shell and tube heat exchanger.

5. The air supply device according to claim 1, characterized in that: A normally open solenoid valve (4) is provided at the pressure inlet (15); and / or a normally closed solenoid valve (5) is provided at the pressure outlet (16).

6. The gas supply device according to claim 1, characterized in that: The air supply device further comprises a first limiting structure (17) and a second limiting structure (18), wherein the first limiting structure (17) is located on a side of the pressure inlet (15) close to the air outlet (14), and the second limiting structure (18) is located on a side of the air outlet (14) close to the pressure inlet (15), and the piston (2) is movably arranged between the first limiting structure (17) and the second limiting structure (18).

7. The gas supply device according to claim 1, characterized in that: The number of the air outlets (14) is at least two, and all the air outlets (14) are distributed in a ring shape with the axis of the shell (1) as the axis, and the air inlet (13) is located on the end surface of the air supply cavity (11).

8. The air supply device according to claim 7, characterized in that: The air supply device further comprises an air outlet pipe, which is arranged in the shell (1), and one end of the air outlet pipe forms the air outlet (14) on the shell (1), and the other end faces the central area of ​​the air supply cavity (11).

9. A heat exchange system, characterized in that: A gas supply device comprising the gas supply device according to any one of claims 1 to 8.

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