Liquid-impingement-resistant refrigerant recovery machine

Abstract

This utility model belongs to the technical field of refrigerant recovery machines, specifically relating to a refrigerant recovery machine with anti-liquid slugging properties. Addressing the shortcomings of existing refrigerant recovery machines with low detection accuracy in their anti-liquid slugging structures, this utility model adopts the following technical solution: a refrigerant recovery machine with anti-liquid slugging properties, comprising: a compressor with a compression inlet and a compression outlet; an inlet valve controlling the intake volume of the compressor's compression inlet; a condenser connected to the compression outlet; a pressure sensor; and a controller connected to the pressure sensor and controlling the inlet valve; wherein the pressure sensor is located between the compression outlet and the condenser, and the controller controls the inlet valve in real time based on the signal from the pressure sensor. In this utility model's anti-liquid slugging refrigerant recovery machine, the pressure sensor is located between the compression outlet and the condenser, upstream of the condenser, thus avoiding the influence of the condenser on the exhaust pressure and achieving more accurate detection.

Description

Technical Field

[0001] This utility model belongs to the technical field of refrigerant recovery machines, specifically relating to a refrigerant recovery machine that prevents liquid slugging. Background Technology

[0002] With increasing environmental awareness and rising refrigerant prices, refrigerant recovery machines are becoming increasingly popular. However, existing refrigerant recovery machines commonly suffer from liquid slugging during the recovery process. This occurs when too much liquid refrigerant enters the compressor cylinder. Due to the incompressible nature of liquids, when the compressor piston reaches near top dead center during operation, the liquid refrigerant cannot be discharged in time, causing the compressor piston to impact with the liquid refrigerant. While minor, short-term liquid slugging has little impact on the machine's lifespan, prolonged and severe liquid slugging with large amounts of liquid refrigerant can easily damage compressor piston rings, bearings, valve assemblies, and other related components. It can also easily damage pressure components (pressure gauges, pressure sensors, pressure protection switches, etc.), not only reducing the machine's lifespan but also potentially causing the entire machine's protection system to fail, leading to safety accidents and directly threatening life and property.

[0003] The existing anti-liquid slugging solution is: an automatic anti-liquid slugging system for a refrigerant recovery machine, including a recovery machine, the compressor inlet of the recovery machine is connected to an air conditioning system, a vibration sensor or a high-precision pressure sensor is provided on the recovery machine, and both the vibration sensor and the high-precision pressure sensor are connected to a controller, which controls the diameter of the inlet in real time based on the detection information of the vibration sensor or the compressor exhaust pressure fluctuation value detected by the high-precision pressure sensor.

[0004] The aforementioned solution can mitigate liquid slugging by installing a high-precision pressure sensor on the recycling machine, but it also has the following drawbacks: the high-precision pressure sensor is located downstream of the condenser and the check valve, and some pressure fluctuations are buffered and filtered by the condenser and the check valve, resulting in lower recognition accuracy and a delay in feedback. Summary of the Invention

[0005] This invention addresses the shortcomings of existing refrigerant recovery machines' anti-liquid-slugging structures, which suffer from low recognition accuracy. It provides an anti-liquid-slugging refrigerant recovery machine by changing the position of the pressure sensor that detects the discharge pressure at the compressor outlet, thereby improving recognition accuracy. Furthermore, by changing the pressure sensor used, the recognition time sensitivity is improved.

[0006] To achieve the above objectives, this utility model adopts the following technical solution: a refrigerant recovery machine to prevent liquid slugging, the refrigerant recovery machine comprising:

[0007] A compressor has a compression inlet and a compression outlet;

[0008] The intake valve controls the amount of air entering the compressor's compression inlet;

[0009] Condenser, connected to the compressor exhaust port;

[0010] Pressure sensor;

[0011] The controller is connected to the pressure sensor and controls the intake valve.

[0012] The pressure sensor is located between the compressor exhaust port and the condenser, and the controller controls the intake valve in real time based on the signal from the pressure sensor.

[0013] The refrigerant recovery machine for preventing liquid slugging of this invention has a pressure sensor located between the compressor exhaust port and the condenser, with the pressure sensor positioned upstream of the condenser. This avoids the influence of the condenser on the exhaust pressure, resulting in more accurate detection.

[0014] As an improvement, the controller compares the difference between the peak and average pressure at the compressor's exhaust port detected by the pressure sensor with the set value.

[0015] As an improvement, the pressure sensor is a high refresh rate pressure sensor, whose sampling time is less than or equal to the time required for a single compression cycle.

[0016] As an improvement, the sampling time of the high refresh rate pressure sensor is less than or equal to 1ms.

[0017] As an improvement, the anti-liquid slugging refrigerant recovery unit also includes a control valve body, which has a valve inlet and a valve outlet. The valve inlet is connected to the compressor inlet, and the valve outlet is connected to the compressor outlet. A pressure sensor is installed on the control valve body and is located upstream of the valve outlet.

[0018] As an improvement, the anti-liquid slugging refrigerant recovery machine also includes a control valve body. The control valve body is provided with a valve inlet and a valve outlet. The valve inlet is connected to the compressor inlet, the valve outlet is connected to the compressor outlet, and the valve outlet is connected to a tee. A pressure sensor is installed on the tee. The valve inlet, compressor inlet, compressor outlet, and valve outlet are connected in sequence.

[0019] As an improvement, the anti-liquid slugging refrigerant recovery unit also includes an exhaust valve located at the compressor's exhaust port, with the intake valve and exhaust valve linked together.

[0020] As an improvement, the intake valve and exhaust valve are linked by a synchronous gear mechanism. The synchronous gear mechanism includes a synchronous gear set and a valve motor that drives the synchronous gear set. The synchronous gear set includes a driving gear fixed to the output shaft of the valve motor, a driven gear meshing with the driving gear, a first air passage gear that rotates coaxially with the driven gear, and a second air passage gear meshing with the first air passage gear. The valve motor is controlled by a controller.

[0021] As an improvement, the first air passage gear is fixed to the manual knob.

[0022] As an improvement, the anti-liquid slugging refrigerant recovery unit also includes a one-way valve, with the pressure sensor located upstream of the condenser and the one-way valve located downstream of the condenser.

[0023] As an improvement, the anti-liquid slugging refrigerant recovery unit also includes a high-pressure sensor and a safety valve located downstream of the one-way valve, with the safety valve located downstream of the high-pressure sensor; the anti-liquid slugging refrigerant recovery unit also includes a low-pressure sensor located at the inlet valve.

[0024] The beneficial effects of this anti-liquid slugging refrigerant recovery machine are as follows: the pressure sensor is located between the compressor exhaust port and the condenser, upstream of the condenser, thus avoiding the influence of the condenser on the exhaust pressure and making the detection more accurate. Furthermore, the pressure sensor is a high refresh rate pressure sensor, whose refresh rate is less than or equal to the time required for a single compression cycle, thereby capturing the pressure changes of the compressor in each compression cycle and providing more timely feedback. Attached Figure Description

[0025] Figure 1 and Figure 2 These are schematic diagrams of the anti-liquid-slugging refrigerant recovery machine according to Embodiment 1 of this utility model from different angles.

[0026] Figure 3 This is a structural block diagram of the anti-liquid-slugging refrigerant recovery machine according to Embodiment 1 of this utility model.

[0027] Figure 4 This is a schematic diagram of the anti-liquid-slugging refrigerant recovery machine according to Embodiment 2 of this utility model.

[0028] Figure 5 This is a structural block diagram of the anti-liquid-slugging refrigerant recovery machine according to Embodiment 2 of this utility model.

[0029] In the diagram, 1 represents the intake valve;

[0030] 2. Low-pressure sensor;

[0031] 30. Control valve body; 31. Valve inlet; 32. Valve outlet;

[0032] 4. Compressor;

[0033] 5. Exhaust valve;

[0034] 6. Pressure sensor;

[0035] 7. Synchronous gear mechanism; 71. Valve motor; 72. Drive gear; 73. Driven gear; 74. First air path gear; 75. Second air path gear; 76. Manual knob;

[0036] 81. Condenser; 82. Check valve; 83. High-pressure sensor; 84. Safety valve;

[0037] 9. Three-way connector. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be explained and described below. However, the following embodiments are only preferred embodiments of the present invention and not all of them. Other embodiments obtained by those skilled in the art based on the embodiments in the implementation methods without creative effort are all within the protection scope of the present invention.

[0039] See Figures 1 to 3 The refrigerant recovery machine for preventing liquid slugging according to an embodiment of the present invention includes:

[0040] A compressor has a compression inlet and a compression outlet;

[0041] The intake valve controls the amount of air entering the compressor's compression inlet;

[0042] Condenser, connected to the compressor exhaust port;

[0043] Pressure sensor;

[0044] The controller is connected to the pressure sensor and controls the intake valve.

[0045] The pressure sensor is located between the compressor exhaust port and the condenser, and the controller controls the intake valve in real time based on the signal from the pressure sensor.

[0046] The anti-liquid-slugging refrigerant recovery machine of this utility model has a pressure sensor located between the compressor exhaust port and the condenser, with the pressure sensor located upstream of the condenser, thereby avoiding the influence of the condenser on the exhaust pressure and making the detection more accurate.

[0047] Example 1

[0048] See Figures 1 to 3 The first embodiment of this utility model discloses a refrigerant recovery machine for preventing liquid slugging, which includes:

[0049] Compressor 4 has a compression inlet and a compression outlet;

[0050] Intake valve 1 controls the amount of air entering the compressor 4 through its compression inlet.

[0051] Condenser 81, connected to the compressor exhaust port;

[0052] Pressure sensor 6;

[0053] The controller is connected to the pressure sensor 6 and controls the intake valve 1.

[0054] The pressure sensor 6 is located between the compressor exhaust port and the condenser 81, and the controller controls the intake valve 1 in real time based on the signal from the pressure sensor 6.

[0055] In this embodiment, the controller compares the difference between the peak pressure and the average pressure at the compressor 4's exhaust port detected by the pressure sensor 6 with a set value.

[0056] In this embodiment, the pressure sensor 6 is a high refresh rate pressure sensor 6. The sampling time of the high refresh rate pressure sensor 6 is less than or equal to the time required for a single compression cycle, thereby capturing the pressure changes of the compressor 4 in real time for each compression cycle and achieving more timely adjustment. The high refresh rate pressure sensor 6 is different from the high precision pressure sensor 6. High refresh rate requires time, while high precision requires accuracy. A certain amount of accuracy can be sacrificed to obtain a high refresh rate. Of course, with technological advancements and / or cost reductions, the high refresh rate pressure sensor 6 can also be a high precision pressure sensor 6.

[0057] In this embodiment, the sampling time of the high refresh rate pressure sensor 6 is less than or equal to 1ms.

[0058] In this embodiment, the anti-liquid slugging refrigerant recovery machine also includes an exhaust valve 5 located at the compressor exhaust port of the compressor 4, and the intake valve 1 and the exhaust valve 5 are linked.

[0059] In this embodiment, the intake valve 1 and the exhaust valve 5 are linked by a synchronous gear mechanism 7. The synchronous gear mechanism 7 includes a synchronous gear set and a valve motor 71 that drives the synchronous gear set. The synchronous gear set includes a driving gear 72 fixed to the output shaft of the valve motor 71, a driven gear 73 meshing with the driving gear 72, a first air passage gear 74 rotating coaxially with the driven gear 73, and a second air passage gear 75 meshing with the first air passage gear 74. The valve motor 71 is controlled by a controller. The first air passage gear 74 can be connected to the intake valve 1 or the exhaust valve 5, and the second air passage gear 75 is connected to the other valve.

[0060] In this embodiment, the first air passage gear 74 is fixedly connected to the manual knob 76.

[0061] In this embodiment, the refrigerant recovery unit with liquid slugging prevention includes an integrated control valve. The integrated control valve includes a control valve body 30 and a valve inlet 31 and a valve outlet 32 ​​disposed on the control valve body 30. The valve inlet 31 is connected to a compression inlet, and the valve outlet 32 ​​is connected to a compression outlet. The valve outlet 32 ​​is connected to a tee 9, and a pressure sensor 6 is mounted on the tee 9. The valve inlet 31, compression inlet, compression outlet, and valve outlet 32 ​​are sequentially connected. An intake valve 1 and an exhaust valve 5 are disposed within the control valve body 30. The integrated control valve includes a control valve body 30, a valve inlet 31, a valve outlet 32, an intake valve 1, and an exhaust valve 5, etc.

[0062] In this embodiment, the refrigerant recovery unit for preventing liquid slugging also includes a one-way valve 82, which is located downstream of the condenser 81. The one-way valve 82 prevents backflow.

[0063] In this embodiment, the anti-liquid slugging refrigerant recovery unit also includes a high-pressure sensor 83 and a safety valve 84 located downstream of the one-way valve 82. The safety valve 84 is located downstream of the high-pressure sensor 83. The high-pressure sensor 83 detects the pressure value in the receiving container to prevent excessive pressure in the receiving container. Both the one-way valve 82 and the high-pressure sensor 83 are mounted on the control valve body 30.

[0064] In this embodiment, the refrigerant recovery machine for preventing liquid slugging also includes a low-pressure sensor 2 located at the inlet valve 1. The low-pressure sensor 2 detects the pressure in the container to be recovered, and when it falls below a certain threshold (which can be as low as 0), it indicates that the recovery is complete.

[0065] See Figure 3 During recycling, the inlet of the recycling machine receives the recycling container. The refrigerant in the container to be recycled first passes through the filter, valve inlet 31, control valve body 30, inlet valve 1, compressor inlet, compressor 4, compressor outlet, exhaust valve 5, three-way valve 9, condenser 81, check valve 82, safety valve 84 and recycling machine outlet, and finally enters the receiving container.

[0066] In this embodiment, the discharge pressure fluctuation limit of compressor 4 is set to 5 bar. The high refresh rate pressure sensor 6 continuously collects the discharge pressure waveform of compressor 4. When the difference between the pressure peak and trough is greater than 5 bar, it is determined that liquid slugging has occurred. The controller uses the synchronous gear mechanism 7 to link the intake valve 1 and the exhaust valve 5, reducing the intake volume of compressor 4 (reducing the diameter of the intake port) until the discharge pressure fluctuation limit of compressor 4 is ≤ 5 bar. When the discharge pressure fluctuation limit of compressor 4 remains ≤ 5 bar for a period of time, the intake volume of compressor 4 is increased.

[0067] The beneficial effects of the anti-liquid slugging refrigerant recovery machine in Embodiment 1 of this utility model are as follows: The pressure sensor 6 is located between the compressor exhaust port and the condenser 81, and the pressure sensor 6 is located upstream of the condenser 81, thereby avoiding the influence of the condenser 81 (and the one-way valve 82) on the exhaust pressure, and the detection is more accurate (the integrated control valve has almost no influence on the exhaust pressure, and the exhaust pressure of the compressor exhaust port 4 and the valve exhaust port 32 of the integrated control valve are almost equal); the pressure sensor 6 is a high refresh rate pressure sensor 6, and the refresh rate of the high refresh rate pressure sensor 6 is less than or equal to the time required for a single compression cycle, thereby capturing the pressure change of each compression cycle of the compressor 4, providing more timely feedback and higher time sensitivity.

[0068] Example 2

[0069] See Figure 4 and Figure 5 In this embodiment, the installation position of the pressure sensor 6 is different.

[0070] In this embodiment, the refrigerant recovery unit for preventing liquid slugging also includes a control valve body 30. The control valve body 30 is provided with a valve inlet 31 and a valve outlet 32. The valve inlet 31 is connected to the compressor inlet, and the valve outlet 32 ​​is connected to the compressor outlet. A pressure sensor 6 is installed on the control valve body 30 and is located upstream of the valve outlet 32. The pressure sensor 6 is located downstream of the compressor outlet.

[0071] In this embodiment, the anti-liquid slugging refrigerant recovery unit includes an integrated control valve. The integrated control valve includes a control valve body 30, a valve inlet 31, a valve outlet 32, an inlet valve 1, and an outlet valve 5. The structure of the integrated control valve is the existing technology (before the installation of the pressure sensor 6). The integrated control valve is a valve structure that integrates refrigerant recovery, charging, and self-cleaning. By integrating the inlet valve 1 and the outlet valve 5 into the integrated control valve, the structure is simplified and the reliability of use is improved.

[0072] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art should understand that the present invention includes, but is not limited to, the content described in the above specific embodiments. Any modifications that do not depart from the functional and structural principles of the present invention will be included within the scope of the claims.

Claims

1. A refrigerant recovery machine with anti-liquid slugging feature, characterized in that: The refrigerant recovery machine for preventing liquid slugging includes: The compressor (4) has a compression inlet and a compression outlet; The intake valve (1) controls the intake volume of the compressor (4) at the compressor intake port; Condenser (81), connected to the compression exhaust port; Pressure sensor (6); The controller is connected to the pressure sensor (6) and controls the intake valve (1); The pressure sensor (6) is located between the compressor exhaust port and the condenser (81), and the controller controls the intake valve (1) in real time based on the signal from the pressure sensor (6).

2. The refrigerant recovery machine for preventing liquid slugging according to claim 1, characterized in that: The controller compares the difference between the peak and average pressure at the compressor (4) exhaust port detected by the pressure sensor (6) with the set value.

3. The refrigerant recovery machine for preventing liquid slugging according to claim 1, characterized in that: The pressure sensor (6) is a high refresh rate pressure sensor (6), and the sampling time of the high refresh rate pressure sensor (6) is less than or equal to the time required for a single compression cycle.

4. The refrigerant recovery machine for preventing liquid slugging according to claim 3, characterized in that: The sampling time of the high refresh rate pressure sensor (6) is less than or equal to 1 ms.

5. The refrigerant recovery machine for preventing liquid slugging according to claim 1, characterized in that: The anti-liquid slugging refrigerant recovery machine also includes a control valve body (30), which has a valve inlet (31) and a valve outlet (32). The valve inlet (31) is connected to the compression inlet, and the valve outlet (32) is connected to the compression outlet. The pressure sensor (6) is installed on the control valve body (30) and is located upstream of the valve outlet (32).

6. The refrigerant recovery machine for preventing liquid slugging according to claim 1, characterized in that: The anti-liquid slugging refrigerant recovery machine also includes a control valve body (30), which is provided with a valve inlet (31) and a valve outlet (32). The valve inlet (31) is connected to the compression inlet, the valve outlet (32) is connected to the compression outlet, and the valve outlet (32) is connected to a tee (9). A pressure sensor (6) is installed on the tee (9). The valve inlet (31), compression inlet, compression outlet, and valve outlet (32) are connected in sequence.

7. The refrigerant recovery machine for preventing liquid slugging according to claim 1, characterized in that: The anti-liquid slugging refrigerant recovery machine also includes an exhaust valve (5) located at the compressor exhaust port of the compressor (4), and the intake valve (1) and exhaust valve (5) are linked.

8. The refrigerant recovery machine for preventing liquid slugging according to claim 7, characterized in that: The intake valve (1) and exhaust valve (5) are linked by a synchronous gear mechanism (7). The synchronous gear mechanism (7) includes a synchronous gear set and a valve motor (71) that drives the synchronous gear set. The synchronous gear set includes a drive gear (72) fixed to the output shaft of the valve motor (71), a driven gear (73) meshing with the drive gear (72), a first air passage gear (74) rotating coaxially with the driven gear (73), and a second air passage gear (75) meshing with the first air passage gear (74). The valve motor (71) is controlled by a controller.

9. The refrigerant recovery machine for preventing liquid slugging according to claim 8, characterized in that: The first air passage gear (74) is fixed to the manual knob (76).

10. The refrigerant recovery machine for preventing liquid slugging according to claim 1, characterized in that: The anti-liquid slugging refrigerant recovery unit also includes a one-way valve (82) located downstream of the condenser (81); and / or, The anti-liquid slugging refrigerant recovery unit also includes a high-pressure sensor (83) and a safety valve (84) located downstream of the one-way valve (82). The safety valve (84) is located downstream of the high-pressure sensor (83). The anti-liquid slugging refrigerant recovery unit also includes a low-pressure sensor (2) located at the inlet valve (1).

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