Oil separator for refrigeration systems at large pressure differences

Abstract

This utility model discloses an oil separator for a refrigeration system under large pressure difference, comprising a housing and an oil-gas separation assembly. The oil-gas separation assembly separates oil from the gas passing through the housing, and the oil flows back to the lubrication system through an oil return port. It also includes a float and an assist device. The housing contains the oil separated from the gas; the assist device acts on the float or the valve needle, with the float acting on the valve needle, which is located at the oil return port of the housing for opening or closing the port. This utility model, by incorporating an assist device to aid in opening the valve needle, avoids the inability to open at the set oil level due to pressure difference between the inside and outside of the housing. This allows the oil in the housing to flow back to the lubrication system for use, ensuring stable operation of the lubrication system. It also prevents excessively high oil levels in the housing, which would cause oil to be discharged with the passing gas, resulting in waste and affecting the operation of other systems.

Description

Technical Field

[0001] This utility model relates to the field of oil separators, and more particularly to an oil separator for a refrigeration system under a large pressure difference. Background Technology

[0002] Oil separators are a very important auxiliary device in refrigeration systems. They help prevent insufficient lubrication in the compressor due to lubricating oil stagnation in the system, which can lead to compressor damage. For a long time, people have focused on reducing costs and improving oil separation efficiency, but have neglected the fundamental issue of protecting the compressor's oil return.

[0003] The widespread attention given to the heat pump function of refrigeration systems has significantly challenged existing usage methods. Increasingly lower evaporation temperatures and increasingly higher condensation temperatures have led to larger pressure ratios and pressure differentials in refrigeration systems. Under these high pressure differentials, the valve needle at the oil return port of the oil separator cannot open properly as originally designed, causing a large amount of oil to remain in the oil separator. This oil then enters the refrigeration system along with the refrigerant gas, resulting in insufficient lubrication and affecting equipment performance. If the oil separator does not have a float valve and relies on pressure differentials and capillary tubes to control the oil return, conventional capillary tube oil return methods are insufficient. Multiple combinations of five or more methods might be needed to meet the oil return requirements, which is impractical in reality. Utility Model Content

[0004] The purpose of this invention is to provide an oil separator for a refrigeration system under large pressure difference, which assists in opening the valve needle by setting an assist device.

[0005] To solve the above technical problems, the following technical solution is adopted: This utility model provides an oil separator for a refrigeration system under a large pressure difference. 1. It includes a shell and an oil-gas separation component. The oil-gas separation component is used to separate oil from the gas passing through the shell. The oil flows back to the lubrication system through the oil return port. The feature is that it also includes a float and an assist device. The shell is filled with the oil separated from the gas. The assist device acts on the float or the valve needle. The float acts on the valve needle, which is located on the oil return port of the housing and is used to open or close the oil return port. The float controls the position of the valve needle according to the oil level in the housing, thereby controlling the opening or closing of the oil return port. The assist device is used to provide an auxiliary force to the float in the same direction as the buoyancy or to provide an auxiliary force to the valve needle to open from the oil return port; When the oil level in the housing is higher than the set value, the float and the assist device cause the valve needle to open from the oil return port; when the oil level in the housing is lower than the set value, the valve needle closes the oil return port.

[0006] Optionally, the assist device includes a compression spring disposed at the bottom of the float, the compression spring having an upward elastic force on the float, assisting the float in opening the valve needle from the oil return port.

[0007] Optionally, the assist device includes a tension spring disposed above the float, one end of the tension spring being mounted on a beam plate and the other end being mounted on the float, the beam plate being mounted on the inner wall of the housing, and the tension spring exerting an upward elastic force on the float to assist the float in opening the valve needle from the oil return port.

[0008] Optionally, the assist device includes a torsion spring, which is mounted on a mounting base disposed on the inner wall of the housing. One end of the torsion spring abuts against the inner wall of the housing, and the other end acts on the float, exerting an upward elastic force on the float.

[0009] Optionally, the assist device also includes a lever structure, wherein the float and the valve needle are spaced apart on the lever structure, and the force transmitted from the float to the valve needle is adjusted by the lever structure.

[0010] Optionally, the lever structure includes an end fulcrum lever, the fulcrum of which is mounted on a hinge seat, the hinge seat being mounted on the bottom or side wall of the housing, the valve needle being disposed on the lever at one end near the fulcrum, and the float being disposed on the lever at one end away from the fulcrum.

[0011] Optionally, the lever structure includes a central fulcrum lever, the fulcrum of which is disposed on a support seat, the support seat being mounted on the bottom or side wall of the housing, and the valve needle and the float ball being disposed at opposite ends of the lever.

[0012] Optionally, it also includes a capillary tube and a filter screen; the oil outlet of the capillary tube is connected to the lubrication system, and the oil inlet is located at the bottom of the housing for discharging the oil retained at the bottom of the housing; the filter screen is provided at the oil inlet of the capillary tube.

[0013] Optionally, the housing is provided with an air inlet and an exhaust outlet. Gas enters from the air inlet, and after passing through the oil-gas separation component inside the housing to separate the oil from the gas, the gas is discharged from the exhaust outlet.

[0014] Optionally, the oil return port is connected to an oil return pipe, which passes through the housing and connects to the lubrication system.

[0015] Compared with the prior art, the beneficial effects achieved by this utility model are as follows: 1. This utility model, by setting an assist device, assists in opening the valve needle, avoiding the inability to open at the set oil level due to the pressure difference inside and outside the housing. This allows the oil in the housing to flow back into the lubrication system for use, ensuring the stable operation of the lubrication system. It also prevents the oil level in the housing from being too high, causing the oil to be discharged with the passing gas, resulting in waste and affecting the operation of other systems.

[0016] 2. The assist device provided in this utility model can adopt a lever structure or a spring structure, or a combination of both. Without changing the original design structure, the assist device can be added to ensure the opening of the valve needle on the oil return port. The structure is simple and easy to install.

[0017] 3. By setting a capillary tube, this utility model can slowly return the oil trapped in the housing to the lubrication system, which can prevent the oil from remaining at the bottom of the housing for a long time, ensuring the minimum circulation oil supply requirement and maintaining the oil level stability in the housing for a long time; it can also prevent the float from frequently moving when the oil level changes frequently above and below the set value, causing frequent fluctuations in the oil supply in the lubrication system, and slowly returning the trapped oil to improve the stability of the oil supply in the lubrication system. Attached Figure Description

[0018] Figure 1 This is a cross-sectional structural schematic diagram of one embodiment of the oil separator of this utility model; Figure 2 This is a cross-sectional structural schematic diagram of another embodiment of the oil separator of this utility model; Figure 3 This is the book Figure 2 Enlarged view of a portion of the image; Figure 4 This is a force characteristic diagram in an embodiment of this utility model; Figure 5 This is a force analysis diagram of the valve needle in an embodiment of this utility model.

[0019] Explanation of reference numerals in the attached figures: 1. Housing; 2. Air inlet; 3. Air outlet; 4. Float; 5. End fulcrum lever; 6. Hinge seat; 7. Middle fulcrum lever; 8. Support seat; 9. Valve needle; 10. Valve seat; 11. Oil return port; 12. Oil return pipe; 13. Compression spring; 14. Tension spring; 15. Beam plate; 16. Torsion spring; 17. Mounting seat one; 18. Capillary tube; 19. Filter screen; 20. Mounting seat two. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use.

[0021] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more. In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0022] Example 1

[0023] This embodiment provides an oil separator for a refrigeration system under a large pressure difference, including a housing 1 and an oil-gas separation component. The refrigeration gas in the refrigeration system passes through the interior of the housing 1, and the oil-gas separation component separates the oil in the refrigeration gas and stores it inside the housing 1. The separated oil is returned to the lubrication system for use through the return port on the return pipe.

[0024] An air inlet 2 and an air outlet 3 are provided at the upper end of the housing 1. The cooling gas enters from the air inlet 2, passes through the oil-gas separation component, and is discharged from the air outlet 3. The oil-gas separation component can use baffles. The gas changes its flow direction after passing through the baffles, generating centrifugal force, which causes oil droplets in the gas to condense on the inner wall of the housing 1 and fall down along the inner wall of the housing 1 for storage inside the housing 1.

[0025] like Figure 1As shown, the housing 1 is provided with a return pipe, and one end of the return pipe located inside the housing 1 is the return port. A valve needle 9 is provided on the return port. The float 4 acts on the valve needle 9. The valve needle 9 is sealed on the return port by the gravity of the float 4, so that the oil in the housing 1 cannot flow out from the return port. When the oil reaches a certain height, the buoyancy of the float 4 overcomes the gravity of the float 4. At the same time, the remaining buoyancy after overcoming the gravity of the float acts on the valve needle 9, opening the valve needle 9 from the oil return port, and the oil flows back from the return port into the lubrication system.

[0026] When the external temperature and humidity change, a pressure difference appears inside and outside the housing 1. This pressure difference causes a change in the opening force of the valve needle. When the pressure difference increases the opening force of the valve needle, when the oil level reaches the set value, the buoyancy force on the float 4 cannot overcome the weight of the float and thus cannot open the valve needle. This reduces the amount of oil flowing back to the lubrication system, thereby reducing the performance of the device. The oil level inside the housing 1 rises, affecting the separation efficiency of the oil-gas separation component inside the housing 1. This causes oil to enter the refrigeration system with the refrigerant gas, resulting in oil waste and impacting the equipment within the refrigeration system. When the pressure difference is large enough that the float is fully submerged and subjected to maximum buoyancy, it still cannot open the valve needle, causing the device to fail. Therefore, the oil separator provided in this embodiment also includes an assist device. Both the float 4 and the assist device act on the valve needle 9. The assist device assists in opening the valve needle 9. The assist device includes a device that provides an upward assist force to the float 4. By providing an upward assist force to the float 4, the valve needle 9 can be opened even when the oil level reaches the set value. Of course, the valve needle 9 can also be opened even when there is no pressure difference.

[0027] like Figure 1 As shown, the assist device used in this embodiment is an end fulcrum lever 5. When transmitting force between the float 4 and the valve needle 9, the magnitude of the force transmitted to the valve needle 9 is changed, so that the weight of the float 4 acts on the end fulcrum lever 5, and then is transmitted to the valve needle 9, thereby sealing the valve needle 9 at the return port 11. When the float opens the valve needle due to buoyancy, the buoyancy is also transmitted to the valve needle 9 through the lever to open the valve needle. By designing the lever arm ratio, the force transmitted to the float acting on the valve needle 9 is adjusted. Figure 1 As described above, one end of the end fulcrum lever 5 is hinged to the hinge seat 6, which is mounted on the side wall of the housing 1. The lever can rotate around point O in the figure. A valve needle 9 is installed at point B of the lever, and the valve needle 9 is positioned downwards at the return port of the return pipe. The float 4 is fixedly installed at point A of the hinge rod. Point B is closer to point O, and point A is farther from point O. The weight of the float 4 acting on point A is transmitted to the valve needle 9 at point B, thereby sealing the valve needle 9 at the return port. When the oil level reaches the set value, the float 4 experiences an upward buoyancy force, which is transmitted to the valve needle at point B through the lever. The valve needle 9 opens, and the oil flows back from the return port to the lubrication system.

[0028] The force on the float 4 is transmitted to the valve needle 9 via the end fulcrum lever 5, thereby assisting in opening the valve needle. Changing the positions of the float 4 and valve needle 9 on the end fulcrum lever 5 changes the magnitude of the transmitted force, thus achieving an assisting effect. Simultaneously changing the distances of points A and B from point O alters the force transmitted from the float 4 to the valve needle 9. When the valve needle opening force increases due to the pressure difference inside and outside the housing 1, moving point A away from point B increases the force transmitted to point B, enabling the valve needle 9 to open when the oil level reaches the set value.

[0029] like Figure 2 As shown, in this embodiment, a capillary tube 18 is also provided inside the housing 1. The capillary tube 18 is connected to the lubrication system and is mounted on the mounting base 20. The mounting base 20 is mounted on the bottom or side wall of the housing 1 to prevent the capillary tube 18 from floating. A filter screen 19 is provided on one end of the capillary tube 18 inside the housing 1. The filter screen 19 is located at the bottom of the housing 1. The oil in the housing 1 slowly flows back to the lubrication system through the filter screen 19 and the capillary tube 18, preventing the oil at the bottom of the housing 1 from stagnating for a long time. It also prevents the oil level in the housing 1 from changing frequently around the set value, so that the float 4 repeatedly acts on the valve needle 9, improving the stability of the oil return of the lubrication system.

[0030] Therefore, in this embodiment, the end fulcrum lever 5 is used as an assist device, which has a simple structure. During the design, the distance difference between point A and point B and point O can be adjusted according to the requirements to realize the magnitude of the force exerted by the float 4 on the valve needle 9.

[0031] Example 2

[0032] This embodiment provides an oil separator for a refrigeration system under a large pressure difference, based on Embodiment 1. The difference is that the assist device uses a central fulcrum lever 7 to realize the transmission of force between the float 4 and the valve needle 9. While transmitting force, it can also change the direction and magnitude of the force. The float 4 acts on one end of the lever, and the valve needle 9 acts on the other end of the lever. The origin of the lever is installed on the support seat 8, which is installed on the bottom or side wall of the housing 1. The oil return pipe 12 extends from the side wall of the housing 1, and its end oil return port 11 bends downward and extends into the oil. The oil return port 11 is located above the valve needle 9. Through the gravity of the float 4 on the other end of the lever, the valve needle 9 located on the other end of the lever is pushed upward, thereby sealing the valve needle 9 in the oil return port 11. When the oil level reaches the set value, the buoyancy of the float 4 reduces the gravity acting on the lever, and the force transmitted to the valve needle 9 decreases. When the oil return port 11 cannot be sealed, the valve needle 9 opens, and the oil flows out from the oil return port 11.

[0033] like Figure 2 , Figure 3As shown, the valve needle 9 is mounted on the valve seat 10, which is installed on the side wall of the housing 1. The float 4 is set by a lever. One end of the float 4 is subjected to a downward force due to the gravity of the float 4, while the other end of the lever is subjected to an upward force, which acts on the valve needle 9 on the valve seat 10. When the force acting on the valve needle 9 is less than the sealing force required for the oil return port, the valve needle 9 opens, and oil enters the lubrication system from the oil return port 11.

[0034] The lever structure can also be combined with other forms of assistive devices. For example, when the lever structure is set, a compression spring 13 is set at the bottom of the float 4 or a tension spring 14 is installed above the float 4 to further assist the opening of the valve needle 9.

[0035] The lever structure can also be designed to have an adjustable origin position. For example, by installing a magnetic element that mates with the support seat 8 on the outside of the housing 1, and ensuring a tight seal, a positioning element can be installed at one end of the lever. During adjustment, the positioning element first fixes one end of the lever in place. Then, driven by the magnetic element, the internal support seat 8 can slide on the lever, thereby changing the origin position and thus adjusting the lever arm size. Alternatively, an adjusting rod can be installed on the hinge seat 6 and extended outward from the housing 1. Ensuring a tight seal, the position of the hinge seat 6 can be adjusted via the adjusting rod, thereby changing the origin position on the lever.

[0036] When the pressure difference between the inside and outside of housing 1 reduces the sealing force required by valve needle 9, the origin is adjusted to a position close to float 4. This reduces the force transmitted from float 4 to valve needle 9 via lever, allowing valve needle 9 to open when the oil level reaches the set value. Conversely, when the pressure difference between the inside and outside of housing 1 increases the sealing force required by valve needle 9, the origin is adjusted to a position close to float 4. This increases the force transmitted from float 4 to valve needle 9 via lever, ensuring the oil level opens within the specified range and preventing premature opening of valve needle 9 and excessive lubrication.

[0037] like Figure 4 As shown, ① is the weight of the float, which is constant; ② is the valve needle opening force, which increases with the increase of the gas pressure inside the housing when the external pressure of the housing is constant; ③ is the spring force of the compression spring, which increases with the increase of the spring compression; ④ is the constant buoyancy of the float when fully submerged or when the return port is open. The initial opening force of the valve needle 9 is the initial sealing force of the valve needle 9. When the opening force provided to the valve needle 9 is less than the sealing force, the valve needle 9 cannot be opened; when the opening force is greater than the sealing force, the valve needle 9 is opened. When the oil level in the housing reaches the set value, the opening force provided by the float 4 to the valve needle 9 is greater than the sealing force, and the valve needle is opened by 9. For example, when the weight of the float 4 is -25 and the valve needle sealing force is 10, when the buoyancy of the float 4 is 35, the valve needle 9 opens from the return port. When an upward auxiliary force is provided by the compression spring 13, the buoyancy of the float 4 is less than 35, and the return port can be opened.

[0038] The float 4 is precisely calculated to distribute the pre-set force under various changing conditions to ensure the reliability of oil discharge from the housing 1. The following is a specific example using a compression spring 13 and a lever structure as the assist device: like Figure 5 As shown, the external pressure of the housing is P2, and the internal pressure of the housing is P1. Ensure the pressure difference at the sealing port between the valve needle 9 and the valve seat 10. Within the range of force calculation, the mechanical loss of the valve group is negligible. The initial sealing force of the valve needle 9 is A. In the absence of external force, providing an upward opening force of magnitude A to the valve needle 9 can open the valve needle 9. Let the upward direction be positive.

[0039] △F = (P1 - P2) / S F y =(F z -F f )·x Among them, F y The preload on the valve needle, when F y When it is a positive number, it provides an opening force to the valve needle; when it is F... y When the value is negative, a sealing force is provided to the valve needle, F. z For the weight of the buoy, F f Where x is the buoyancy of the float, x is the lever ratio, and S is the cross-sectional area of ​​the valve needle. When F y When +△F is greater than the sealing force A, valve needle 9 opens from the oil return port. When F y When +△F is less than the sealing force A, the valve needle 9 seals at the oil return port.

[0040] Example 3

[0041] This embodiment provides an oil separator for a refrigeration system under large pressure difference. The assist device also includes a compression spring 13 acting on the float 4 or a tension spring 14 acting on the float 4, or a combination of both.

[0042] like Figure 2 As shown, one end of the tension spring 14 is mounted on the beam plate 15, and the other end is mounted on the top of the float 4. Both ends of the beam plate 15 are fixed to the inner wall of the housing 1. The width and installation height of the beam plate 15 do not affect the operation of the oil-gas separation component on it, nor do they affect the fall of the oil. The tension spring 14 has upward elastic potential energy. The tension spring 14 provides an upward force to the float 4, so that when the oil level reaches the set value under the pressure difference between the inside and outside of the housing 1, the elastic force of the tension spring 14 and the buoyancy of the float 4 together overcome the action of the float 4, thereby reducing the force acting on the valve needle 9 and enabling the valve needle 9 to open.

[0043] One end of the compression spring 13 is installed at the inner bottom of the housing 1, and the other end is installed at the bottom of the float 4. The compression spring 13 has upward elastic potential energy and provides an upward force to the float 4.

[0044] Both the tension spring 14 and the compression spring 13 are cylindrical. In use, both can be installed on the float 4 simultaneously to provide a larger auxiliary force, or a single tension spring 14 or compression spring 13 can be used. During the design, the compression amount of the compression spring 13 or the extension amount of the tension spring 14 is determined according to the required auxiliary force.

[0045] Example 4

[0046] This embodiment provides an oil separator for a refrigeration system under a large pressure difference, based on Embodiment 1. Figure 2 As shown, the assist device also includes a torsion spring 16, which is mounted on a mounting base 17. The mounting base 17 is located on the inner wall of the housing 1. One end of the torsion spring 16 abuts against the inner wall of the housing 1, and the other end is located at the bottom of the float 4. It has an upward elastic force on the float 4, providing an upward auxiliary force to the float 4 to assist in opening the valve needle 9.

[0047] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. An oil separator for a refrigeration system under high pressure differential, comprising a housing and an oil-gas separation assembly, wherein the oil-gas separation assembly is used to separate oil from the gas passing through the housing, and the oil flows back to the lubrication system through an oil return port, characterized in that... It also includes a float and a booster device, and the housing contains oil separated from the gas; The assist device acts on the float or valve needle, the float acts on the valve needle, and the valve needle is located on the oil return port of the housing for opening or closing the oil return port; the float controls the position of the valve needle according to the oil level in the housing, thereby controlling the opening or closing of the oil return port; The assist device is used to provide an auxiliary force to the float in the same direction as the buoyancy or to provide an auxiliary force to the valve needle to open from the oil return port; When the oil level in the housing is higher than the set value, the float and the assist device cause the valve needle to open from the oil return port; when the oil level in the housing is lower than the set value, the valve needle closes the oil return port.

2. The oil separator for a refrigeration system under large pressure differential as described in claim 1, characterized in that, The assist device includes a compression spring disposed at the bottom of the float, the compression spring exerting an upward elastic force on the float, assisting the float in opening the valve needle from the oil return port.

3. The oil separator of a refrigeration system under large pressure difference according to claim 1, characterized by, The assist device includes a tension spring disposed above the float. One end of the tension spring is mounted on a beam plate, and the other end is mounted on the float. The beam plate is mounted on the inner wall of the housing. The tension spring exerts an upward elastic force on the float, assisting the float in opening the valve needle from the oil return port.

4. The oil separator of a refrigeration system under large pressure difference according to claim 1, characterized by, The assist device includes a torsion spring, which is mounted on a mounting base located on the inner wall of the housing. One end of the torsion spring abuts against the inner wall of the housing, and the other end acts on the float, exerting an upward elastic force on the float.

5. An oil separator for a refrigeration system operating at large pressure differentials according to any one of claims 1-4, characterized in that, The assist device also includes a lever structure, on which the float and valve needle are spaced apart, and the force transmitted from the float to the valve needle is adjusted by the lever structure.

6. The oil separator of a refrigeration system under large pressure difference according to claim 5, characterized by, The lever structure includes an end fulcrum lever, the fulcrum of which is mounted on a hinge seat, which is mounted on the bottom or side wall of the housing. The valve needle is located on the lever at one end near the fulcrum, and the float is located on the lever at one end away from the fulcrum.

7. The oil separator of a refrigeration system under large pressure difference according to claim 5, characterized by, The lever structure includes a central fulcrum lever, the fulcrum of which is set on a support seat, which is mounted on the bottom or side wall of the housing, and the valve needle and the float ball are respectively set at both ends of the lever.

8. The oil separator for a refrigeration system under large pressure differential as described in claim 1, characterized in that, It also includes a capillary tube and a filter screen; the oil outlet of the capillary tube is connected to the lubrication system, and the oil inlet is located at the bottom of the housing to discharge the oil stagnant at the bottom of the housing; the filter screen is provided at the oil inlet of the capillary tube.

9. The oil separator for a refrigeration system under large pressure differential as described in claim 1, characterized in that, The housing is provided with an air inlet and an exhaust outlet. Gas enters from the air inlet, and after passing through the oil-gas separation component inside the housing to separate the oil from the gas, the gas is discharged from the exhaust outlet.

10. The oil separator of a refrigeration system under large pressure difference according to claim 1, characterized by, The oil return port is connected to an oil return pipe, which passes through the housing and connects to the lubrication system.

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