CN114812000A

CN114812000A - Oil return device of dual-mode fluorine pump refrigeration system, control method of oil return device and machine room air conditioner

Info

Publication number: CN114812000A
Application number: CN202210571420.XA
Authority: CN
Inventors: 黄玉优; 林海佳; 赖桃辉; 赵敏娜; 赵材波
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2022-05-24
Filing date: 2022-05-24
Publication date: 2022-07-29
Anticipated expiration: 2042-05-24
Also published as: CN114812000B

Abstract

The invention discloses an oil return device of a double-mode fluorine pump refrigerating system, a control method thereof and a machine room air conditioner, wherein the device comprises the following components: the oil collecting tank is arranged in the tank body, the oil suction assembly is arranged in the oil collecting tank and communicated with the oil return assembly, and the floating plug assembly is arranged at the bottom of the oil collecting tank and part of the floating plug assembly can extend out; the oil collecting tank can float in a lubricating oil layer formed after the oil-liquid mixture is layered, and the bottom of the oil collecting tank can be immersed in the lubricating oil layer or the liquid refrigerant layer; along with the change of the thickness of the lubricating oil layer, the first part and the second part of the floating plug component float up and down so that the lubricating oil in the lubricating oil layer is collected into the oil collecting tank; the oil suction assembly floats on the lubricating oil in the oil collecting tank to suck the lubricating oil, and then the lubricating oil is conveyed back to the double-mode fluorine pump refrigerating assembly through the oil return assembly. This scheme, through the different spare parts that utilize the material preparation liquid storage pot of different density, partial lubricating oil when the fluid layering appears in can collecting and retrieving the liquid storage pot is favorable to promoting the reliability of compressor refrigeration operation.

Description

Oil return device of dual-mode fluorine pump refrigeration system, control method of oil return device and machine room air conditioner

Technical Field

The invention belongs to the technical field of air conditioners, and particularly relates to an oil return device of a double-mode fluorine pump refrigeration system, a control method of the oil return device and a machine room air conditioner.

Background

The data center is provided with various data processing devices. With the large application of 4G and the gradual popularization of 5G, the heat generation amount of various data processing devices is increasing, and the requirements of data centers on the cooling capacity and the energy conservation of air conditioning equipment are also increasing.

The outdoor natural cold source in the transition season and the cold winter is adopted to cool the data center, so that the operating cost of the air conditioning equipment can be greatly reduced. In some embodiments, the air conditioning system employs a dual-mode fluorine pump refrigeration system (e.g., a fluorine pump air conditioner).

In a dual-mode fluorine pump refrigeration system (such as a fluorine pump air conditioner), when a heat pipe and a heat pump are combined to form a shared system, a larger liquid storage tank is required to be arranged in the combined shared system of the heat pipe and the heat pump to adjust the difference of the circulation amount of refrigerant between the heat pipe and the heat pump. However, when the fluorine pump heat pipe operates, oil in the liquid storage tank can be layered, oil shortage in the starting stage of the compressor can be caused, the compressor can be damaged in serious conditions, and the reliability of refrigeration operation of the compressor is influenced.

The above is only for the purpose of assisting understanding of the technical aspects of the present invention, and does not represent an admission that the above is prior art.

Disclosure of Invention

The invention aims to provide an oil return device of a dual-mode fluorine pump refrigerating system, a control method of the oil return device and a machine room air conditioner, and aims to solve the problems that when a fluorine pump heat pipe of the dual-mode fluorine pump refrigerating system runs, oil is deficient in a compressor starting stage due to the fact that oil in a liquid storage tank is layered, even the compressor is damaged, and the reliability of the refrigerating operation of the compressor is affected.

The invention provides an oil return device of a double-mode fluorine pump refrigerating system, wherein the double-mode fluorine pump refrigerating system can operate in a refrigerating mode or a fluorine pump mode; the oil return device of the double-mode fluorine pump refrigerating system comprises: the double-mode fluorine pump refrigerating assembly, the liquid storage tank and the oil return assembly; the liquid storage pot includes: the oil collection tank comprises a tank body, an oil collection tank, an oil absorption assembly and a floating plug assembly; wherein the liquid storage tank is communicated with the dual-mode fluorine pump refrigerating assembly; the oil collecting tank is arranged in the tank body; the oil suction assembly is arranged inside the oil collecting tank and can be communicated to the oil return assembly; the floating plug assembly is arranged at the bottom of the oil collecting tank, a first part of the floating plug assembly is positioned in the oil collecting tank, and a second part of the floating plug assembly can extend out of the bottom of the oil collecting tank so as to float up and down under the buoyancy action of an oil-liquid mixture in the tank body; fluid mixture in the jar body includes: lubricating oil and liquid refrigerant; under the condition that the oil-liquid mixture in the tank body is layered due to the fact that the density of the lubricating oil is different from the density of the liquid refrigerant, the oil collecting tank can float in a lubricating oil layer formed after the oil-liquid mixture is layered, and the bottom of the oil collecting tank can be completely immersed in the lubricating oil layer or partially immersed in the liquid refrigerant layer; along with the change of the thickness of the lubricating oil layer after the oil-liquid mixture is layered, the first part and the second part of the floating plug component float up and down to enable the lubricating oil in the lubricating oil layer to be at least partially collected into the oil collecting tank, so that the separation of the lubricating oil in the oil-liquid mixture is realized; the oil collecting tank is collected with under the condition of the lubricating oil in the fluid mixture, the oil absorption subassembly floats on the lubricating oil in the oil collecting tank and at least partially absorb lubricating oil after, through the oil return subassembly will lubricating oil in the oil collecting tank is at least partially carried back in the double mode fluorine pump refrigeration subassembly, the realization is right the recovery of the lubricating oil in the fluid mixture.

In some embodiments, the dual mode fluorine pump refrigeration assembly comprises: the system comprises a compressor, a first heat exchanger, a four-way valve, a first throttling element, a fluorine pump, a second heat exchanger and a first one-way unit; the oil return device of the double-mode fluorine pump refrigerating system comprises: the dual-mode fluorine pump refrigerating assembly and the liquid storage tank; the liquid storage tank is provided with a first inlet and outlet pipe, an oil pipe and a second inlet and outlet pipe; the first inlet and outlet pipe and the second inlet and outlet pipe can extend into the oil-liquid mixture in the tank body and can extend into the layered liquid refrigerant; when one of the first inlet and outlet pipe and the second inlet and outlet pipe is an inlet pipe, the other one is an outlet pipe; the top of the oil collecting tank is provided with a balance hole; the oil pipe enables the oil suction assembly to be communicated with the oil return assembly through the balance hole; the bottom of the oil collecting tank is provided with an oil collecting hole; the floating plug assembly can float up and down through the oil collecting hole; the outlet of the first unidirectional unit and the exhaust port of the compressor are communicated to a first inlet and outlet pipe of the liquid storage tank after passing through the first heat exchanger; the oil return assembly is communicated to an air suction port of the compressor; a second inlet and outlet pipe of the liquid storage tank is communicated to a D port of the four-way valve; the port C of the four-way valve passes through the first throttling element and the second heat exchanger and then is respectively communicated to an inlet of the first one-way unit and an air suction port of the compressor; an S port of the four-way valve, the first throttling element and an outlet of the fluorine pump are communicated to an inlet of the second heat exchanger together; and an E port of the four-way valve is communicated to an inlet of the first one-way unit and an air suction port of the compressor respectively after passing through the fluorine pump and the second heat exchanger.

In some embodiments, the oil return assembly comprises: an oil return line; the oil suction assembly at least partially conveys lubricating oil in the oil collecting tank back to the dual-mode fluorine pump refrigerating assembly through the oil return pipeline, and the lubricating oil in the oil-liquid mixture is recovered.

In some embodiments, on the oil return line, at least one of a second throttling element, a switching unit and a second one-way unit is further provided; the oil suction assembly can be communicated to an inlet of the second one-way unit under the condition that the second one-way unit is arranged on the oil return pipeline; and the outlet of the second one-way unit can be communicated to the air suction port of the compressor.

In some embodiments, the oil absorption assembly comprises: an oil absorbing member and a hose; the oil suction piece can float on the lubricating oil in the oil collecting tank and at least partially suck the lubricating oil in the oil collecting tank; the hose is communicated to the inside of the oil suction piece and can at least partially convey the lubricating oil sucked by the oil suction piece to the oil return assembly.

In some embodiments, the oil absorbing member includes: an oil absorption ball; the oil suction ball is a hollow ball, and more than one oil passing hole is formed in the hollow ball, so that lubricating oil in the oil collecting tank can at least partially enter the oil suction ball through the oil passing holes; the hose is communicated to the inside of the oil suction ball.

In some embodiments, the number of float plug assemblies is more than one; the number of the oil collecting holes at the bottom of the oil collecting tank is the same as that of the floating plug assemblies; each of the float plug assemblies comprising: the device comprises a stop block, a floating plug rod and a floating plug; the check block is arranged at the top of the floating plug rod and is positioned inside the oil collecting tank; the floating plug is positioned at the bottom of the floating plug rod and positioned outside the oil collecting tank; the floating plug rod penetrates through the oil collecting hole, and can cooperate with the change of buoyancy of lubricating oil in the oil liquid mixture in the tank body and buoyancy of liquid refrigerant the dog with the floating plug floats up and down in the oil collecting hole that corresponds, so as to with lubricating oil after the layering in the oil liquid mixture in the tank body is collected to the inside of oil collecting tank through the oil collecting hole that corresponds at least partially.

In some embodiments, the number of float plug assemblies is two; and the two floating plug assemblies are symmetrically arranged relative to the central axis of the oil collecting tank.

In some embodiments, in a case where the stopper and the floating plug are horizontally disposed and the floating plug rod is vertically disposed, the stopper has a cross-sectional area larger than that of the floating plug rod and smaller than that of the floating plug; after the oil-liquid mixture in the tank body is layered, if the thickness of a layered lubricating oil layer is smaller than a set minimum thickness, the oil collecting tank is close to a layered liquid refrigerant; if the thickness of the layered lubricating oil layer is increased, the oil collecting tank is far away from the layered liquid refrigerant and is close to or even enters the layered lubricating oil layer; when the floating plug rod moves downwards to the set lowest limit, the stop block is clamped at the upper part of the corresponding oil collecting hole to prevent the floating plug rod from falling off from the bottom of the oil collecting tank; when the floating plug rod moves upwards to the set uppermost limit, the upper surface of the floating plug is attached to the bottom of the oil collecting tank, and the floating plug completely blocks the corresponding oil collecting hole, so that liquid refrigerant in the tank body is prevented from entering the oil collecting tank.

In some embodiments, the stopper and the floating plug are both disc-shaped on the plane of the lubricating oil layer.

In some embodiments, the stopper is provided with one or more through holes penetrating in a moving direction of the floating plug rod to increase an oil passing area of the lubricating oil inside the oil collecting tank.

In some embodiments, wherein in the case where the density of the lubricating oil in the dual-mode refrigeration system is less than the density of the liquid refrigerant, the tank density of the oil trap, the density of the lubricating oil, the density of the floating plug, and the density of the liquid refrigerant increase in sequence; under the condition that the density of lubricating oil in the dual-mode refrigeration system is greater than that of liquid refrigerant, the density of the liquid refrigerant, the density of a tank body of the oil collecting tank, the density of the lubricating oil and the density of the floating plug are sequentially increased; the density of the oil collecting tank body can be set by at least one of the material and/or the structure of the oil collecting tank body; the density of the floating plug can be set by at least one of the material and/or structure of the floating plug.

In accordance with another aspect of the present invention, there is provided a machine room air conditioner including: the oil return device of the double-mode fluorine pump refrigerating system is described above.

The present invention further provides a method for controlling an oil return device of a dual-mode fluorine pump refrigeration system, which is matched with the oil return device of the dual-mode fluorine pump refrigeration system, and comprises: step S110, determining the operation mode of the dual-mode fluorine pump refrigerating system; the operation mode of the double-mode fluorine pump refrigerating system is a refrigerating mode or a fluorine pump mode; step S120, under the condition that the dual-mode fluorine pump refrigerating system operates in a refrigerating mode, determining the oil temperature superheat degree of a compressor in the dual-mode fluorine pump refrigerating system, or determining the duration of the dual-mode fluorine pump refrigerating system without oil return control, and determining whether oil return operation needs to be executed or not according to the oil temperature superheat degree of the compressor in the dual-mode fluorine pump refrigerating system or the duration of the dual-mode fluorine pump refrigerating system without oil return control; if oil return operation needs to be executed, controlling a pipeline where the oil return assembly is located to be communicated; if the oil return operation is not required to be executed, controlling a pipeline where the oil return assembly is located to be closed; and S130, under the condition that the dual-mode fluorine pump refrigerating system operates in a fluorine pump mode, controlling a pipeline where the oil return assembly is located to be closed so as to prevent refrigerant at an outlet of an evaporator in the dual-mode fluorine pump refrigerating system from returning to the liquid storage tank.

Therefore, according to the scheme of the invention, different parts (such as the oil collecting tank and the floating plug assembly) of the liquid storage tank are manufactured by using materials with different densities, so that the arrangement of the tank body density of the oil collecting tank and the floating plug assembly density is realized, the separation of lubricating oil and liquid refrigerant is realized by using the density difference of the lubricating oil and the liquid refrigerant, and the collection of the lubricating oil is realized, so that the parts of the liquid storage tank which are layered with the oil can be collected and recovered by manufacturing the different parts of the liquid storage tank by using the materials with different densities, and the reliability of the refrigeration operation of the compressor is favorably improved.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.

Drawings

FIG. 1 is a schematic structural diagram of an oil return device of a dual-mode fluorine pump refrigeration system according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of the dual-mode fluorine pump refrigeration system of the present invention when operating in the compression mode, i.e. when the compressor is on and the fluorine pump is off;

FIG. 3 is a schematic structural diagram of the dual-mode fluorine pump refrigeration system of the present invention operating in the fluorine pump mode, i.e., when the compressor is stopped and the fluorine pump is operating;

FIG. 4 is an enlarged schematic view of one embodiment of a reservoir in the dual mode fluorine pump refrigeration system of the present invention;

fig. 5 is a schematic flow chart illustrating a method for controlling an oil return device of a dual-mode fluorine pump refrigeration system according to an embodiment of the present invention.

The reference numbers in the embodiments of the present invention are as follows, in combination with the accompanying drawings:

1-a compressor; 2-a first heat exchanger (e.g. a condenser); 20-a first fan (e.g. an outdoor fan); 3-a liquid storage tank; 30-tank body; 31-inlet pipe; 32-oil pipe; 33-an outlet pipe; 34-a balancing hole; 35-an oil return hose; 36-an oil-absorbing ball; 37-a stopper; 38-floating plug rod; 39-a floating plug; 40-an oil collecting tank; 4-a four-way valve; 5-a throttle valve; 6-fluoro pump; 7-a second heat exchanger (e.g. an evaporator); 70-a second fan (e.g. an indoor fan); 8-first check valve (e.g. check valve a); 9-a second one-way valve (e.g., one-way valve B); 10-an electromagnetic valve; 11-capillary tube.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the specific embodiments of the present invention and the corresponding drawings. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

A dual-mode fluorine pump refrigeration system (such as a fluorine pump air conditioner) has a refrigeration mode and a fluorine pump mode. In winter or transition season, the outdoor cold air is very suitable to be used as a natural cold source, at the moment, a fluorine pump mode is started, the operation of a compressor is stopped in the fluorine pump mode, a fluorine pump is used for driving a refrigerant to realize the cooling operation of a heat pipe, and the heat pipe transfers the cold energy of the outdoor natural cold source (namely, the cold air) in winter or transition season into the room to cool the data center, so that the operation cost of the air conditioning equipment is greatly reduced.

A dual-mode fluorine pump refrigeration system (such as a fluorine pump air conditioner) is used as a split air conditioner, and usually adopts a mechanically driven split heat pipe, for example, a liquid pump or an air pump and other fluorine pumps are used to drive the heat pipe. The mechanical driven separated heat pipe is one heat pipe system with two or more parts, the evaporating section and the condensing section are manufactured and distributed separately and assembled into one integral in site, and the two parts are connected via pipeline for long distance heat transfer. Generally, integral heat pipes are not capable of remote heat transfer relative to integrally fabricated heat pipes.

When the heat pipe and the heat pump share the same system, a throttling element and a solenoid valve are generally designed in parallel. When the heat pump operates, the electromagnetic valve is closed, and the refrigerant performs pressure reduction operation through the throttling element; when the heat pipe operates, the electromagnetic valve is opened, and the refrigerant mainly passes through the electromagnetic valve with low resistance, so that the large resistance of the throttling element is prevented from consuming most gravity action or the lift of the fluorine pump.

When the heat pipe and the heat pump are combined to form a shared system, although many parts can be reduced, debugging and optimization of the heat pipe and heat pump combined shared system are very complex problems, and some problems which cannot be ignored exist in the aspect of the reliability operation of the heat pipe and heat pump combined shared system. Such as: the refrigerant circulating amount in the compression refrigeration mode is much larger than that of the refrigerant circulating amount of the fluorine pump heat pipe, and a larger liquid storage tank is usually arranged in a common system combining the heat pipe and the heat pump to adjust the difference of the refrigerant circulating amounts between the heat pipe and the heat pump. Because the heat pipe and the heat pump are combined to share the system, the refrigerant quantity required by different circulation is different, but one system is shared, a liquid storage tank is required to be arranged, and redundant refrigerant can be stored in the liquid storage tank; if redundant refrigerant is not stored in the liquid storage tank, excessive refrigerant can exist in the heat pipe and heat pump combined sharing system, the heat pipe and heat pump combined sharing system can occupy the heat exchange area and the like of the heat pipe and heat pump combined sharing system, and therefore the heat exchange area of the heat pipe and heat pump combined sharing system is insufficient, and the heat exchange efficiency of the heat pipe and heat pump combined sharing system is reduced.

The fluorine pump heat pipe runs at low outdoor temperature, the low-temperature liquid refrigerant and the lubricating oil returned by the outdoor condenser easily generate oil stratification in the liquid storage tank, the lubricating oil at the moment is not easy to return to the compressor which is just started along with the liquid refrigerant, oil shortage at the starting stage of the compressor is possibly caused, and the compressor is damaged in serious cases.

Therefore, the phenomenon of oil stratification in the liquid storage tank caused by the operation of the fluorine pump heat pipe needs to be considered, stratified lubricating oil can be ensured to return to the compressor oil sump in time when the compressor is started for refrigeration, and the reliable operation of compression refrigeration is ensured.

According to an embodiment of the invention, an oil return device of a dual-mode fluorine pump refrigeration system is provided. Referring to fig. 1, a schematic diagram of an embodiment of the apparatus of the present invention is shown. The dual-mode fluorine pump refrigeration system can operate in a refrigeration mode or a fluorine pump mode. The oil return device of the double-mode fluorine pump refrigerating system comprises: the dual-mode fluorine pump refrigeration assembly, the liquid storage tank 3 and the oil return assembly. The liquid storage tank 3 includes: the oil collecting tank comprises a tank body 30, an oil collecting tank 40, an oil absorption assembly and a floating plug assembly.

The liquid storage tank 3 is communicated with the dual-mode fluorine pump refrigerating assembly; the oil collecting tank 40 is arranged in the tank body 30. The oil suction assembly is arranged inside the oil collecting tank 40 and can be communicated to the oil return assembly. The floating plug assembly is arranged at the bottom of the oil collecting tank 40, a first part of the floating plug assembly is positioned inside the oil collecting tank 40, and a second part of the floating plug assembly can extend out of the bottom of the oil collecting tank 40 so as to float up and down under the buoyancy of the oil-liquid mixture in the tank body 30. The oil-liquid mixture in the tank 30 includes: lubricating oil and liquid refrigerant.

In the case where the oil-liquid mixture in the tank 30 is layered due to the difference between the density of the lubricating oil and the density of the liquid refrigerant, the oil collection tank 40 floats in the layer of the lubricating oil after the oil-liquid mixture is layered, and the bottom of the oil collection tank 40 is completely immersed in the layer of the lubricating oil or partially immersed in the layer of the liquid refrigerant. Along with the change of the thickness of the lubricating oil layer after the oil-liquid mixture is layered, the first part and the second part of the floating plug component float up and down, so that the lubricating oil in the lubricating oil layer is at least partially collected in the oil collecting tank 40, and the separation of the lubricating oil in the oil-liquid mixture is realized.

Under the condition that the oil collecting tank 40 collects the lubricating oil in the oil-liquid mixture, the oil suction component floats on the lubricating oil in the oil collecting tank 40 and at least partially sucks the lubricating oil, and then the lubricating oil in the oil collecting tank 40 is at least partially conveyed back to the double-mode fluorine pump refrigerating component through the oil return component, so that the lubricating oil in the oil-liquid mixture is recovered.

Fig. 2 is a schematic structural diagram of the dual-mode fluorine pump refrigeration system of the present invention when operating in the compression mode, that is, when the compressor is operating and the fluorine pump is stopped. Fig. 3 is a schematic structural diagram of the dual-mode fluorine pump refrigeration system of the present invention operating in the fluorine pump mode, i.e., the compressor is stopped and the fluorine pump is operating. The scheme of the invention provides an oil return device of a dual-mode fluorine pump refrigerating system and a control scheme thereof, and the oil return device can realize automatic separation and collection of lubricating oil by accurately designing the density of a tank body of an oil collecting tank in a liquid storage tank and the density of a floating plug assembly and utilizing the density difference of the lubricating oil and a liquid refrigerant, so that the lubricating oil is automatically separated and collected, a complex mechanical structure and electric control are not needed, and the problems of separation and collection of the lubricating oil when oil in the liquid storage tank is layered under the low-temperature condition of the dual-mode fluorine pump refrigerating system can be solved. And the oil return control system of the oil return device of the double-mode fluorine pump refrigerating system can avoid the return of excessive lubricating oil and solve the problem of oil return control of the lubricating oil which is separated and collected to return to the compressor, thereby being beneficial to improving the reliability of the refrigerating operation of the compressor.

In some embodiments, the dual mode fluorine pump refrigeration assembly comprises: the system comprises a compressor 1, a first heat exchanger 2, a four-way valve 4, a first throttling element, a fluorine pump 6, a second heat exchanger 7 and a first one-way unit. A first throttle element such as a throttle valve 5 and a first check unit such as a first check valve (e.g., check valve a) 8. The liquid storage tank 3 is provided with a first inlet and outlet pipe, an oil pipe 32 and a second inlet and outlet pipe. The first inlet and outlet pipe and the second inlet and outlet pipe can both extend into the oil-liquid mixture in the tank body 30 and can extend into the layered liquid refrigerant. When one of the first inlet and outlet pipe and the second inlet and outlet pipe is an inlet pipe, the other one is an outlet pipe. A first inlet and outlet pipe such as inlet pipe 31, and a second inlet and outlet pipe such as outlet pipe 33. The top of the oil collecting tank 40 is provided with a balance hole 34. The oil pipe 32 is used for communicating the oil suction assembly with the oil return assembly through the balance hole 34. The bottom of the oil collecting tank 40 is provided with an oil collecting hole. The floating plug assembly can float up and down through the oil collecting hole.

The outlet of the first unidirectional unit and the exhaust port of the compressor 1 are communicated to a first inlet and outlet pipe of the liquid storage tank 3 after passing through the first heat exchanger 2. The oil return assembly is communicated to an air suction port of the compressor 1. And a second inlet and outlet pipe of the liquid storage tank 3 is communicated to a D port of the four-way valve 4. The port C of the four-way valve 4 is communicated with the inlet of the first one-way unit and the suction port of the compressor 1 respectively after passing through the first throttling element and the second heat exchanger 7; an S port of the four-way valve 4 and outlets of the first throttling element and the fluorine pump 6 are communicated to an inlet of the second heat exchanger 7 together; and an E port of the four-way valve 4 is communicated with an inlet of the first one-way unit and an air suction port of the compressor 1 respectively after passing through the fluorine pump 6 and the second heat exchanger 7.

As shown in fig. 2 and 3, the dual-mode fluorine pump refrigeration assembly comprises: the system comprises a compressor 1, a first heat exchanger (such as a condenser) 2, a first fan (such as an outdoor fan) 20 which is matched with the first heat exchanger (such as a condenser) 2, a liquid storage tank 3, a four-way valve 4, a throttle valve 5, a fluorine pump 6, a second heat exchanger (such as an evaporator) 7, a second fan (such as an indoor fan) 70 which is matched with the second heat exchanger (such as an evaporator) 7, and a first check valve (such as a check valve A) 8. Among them, the four-way valve 4 is preferably a pressure difference driven four-way valve, such as the pressure difference driven four-way valve described in the prior application having application No. 202111396002.3 filed by the present applicant.

In the example shown in fig. 2 and fig. 3, the compressor 1 is connected in parallel with the first check valve (e.g., check valve a)8, the flow direction of the first check valve (e.g., check valve a)8 is directed from the suction port of the compressor 1 to the exhaust port of the compressor 1, specifically, the pipeline where the suction port of the compressor 1 is located is communicated with the pipeline where the inlet of the first check valve (e.g., check valve a)8 is located, and the pipeline where the exhaust port of the compressor 1 is located is communicated with the pipeline where the outlet of the first check valve (e.g., check valve a)8 is located. The pipeline where the exhaust port of the compressor 1 is located is communicated to the pipeline where the inlet of the first heat exchanger (such as a condenser) 2 is located, the pipeline where the outlet of the first heat exchanger (such as a condenser) 2 is located is communicated to the pipeline where the inlet of the liquid storage tank 3 is located (such as an inlet pipe 31 of the liquid storage tank 3), and the pipeline where the outlet of the liquid storage tank 3 is located (such as an outlet pipe 33 of the liquid storage tank 3) is communicated to a port D of the four-way valve 4. The pipeline where the oil pipe 32 of the liquid storage tank 3 is located is communicated to the air suction port of the compressor 1 through the oil return component.

FIG. 4 is an enlarged schematic view of one embodiment of a receiver in the dual mode fluorine pump refrigeration system of the present invention. As shown in fig. 4, the liquid reservoir tank 3 includes: a tank 30, an inlet pipe 31, an oil pipe 32, an outlet pipe 33, an oil collecting tank 40, and a floating plug assembly. Tank 30 has liquid refrigerant therein, and sump 40 is located inside tank 30 and is submerged on the liquid refrigerant in tank 30, specifically, a portion of sump 40 is submerged in the liquid refrigerant in tank 30 and another portion of sump 40 is floating above the liquid refrigerant in tank 30.

In the example shown in fig. 4, the tank 30 of the liquid storage tank 3 has an inlet and an outlet at the top, and the tank 30 is a closed high-pressure tank. The inlet and the outlet may be located at the top of the tank 30 relative to the position of the oil collection tank 40 within the tank 30, and may enable the corresponding inlet pipe 31 and outlet pipe 33 to avoid the oil collection tank 40 and the float plug assembly. A first portion of the inlet pipe 31 extends out of the top of the tank 30, a second portion of the inlet pipe 31 extends into the tank 30 from the outside of the tank 30 through the inlet, and a nozzle of the second portion of the inlet pipe 31 extends into the liquid refrigerant inside the tank 30. Similarly, a first portion of the outlet pipe 33 extends out of the top of the tank 30, a second portion of the outlet pipe 33 extends into the tank 30 from the outside of the tank 30 through the inlet, and a nozzle of the second portion of the outlet pipe 33 extends into the liquid refrigerant inside the tank 30.

Preferably, the inlet pipe 31 of the liquid storage tank 3 and the outlet pipe 33 of the liquid storage tank 3 are not distinguished (for example, the structure and the arrangement position are the same, one is used for inlet and the other is used for outlet), so that connection errors are avoided, and the use efficiency is improved.

In some embodiments, the oil return assembly comprises: an oil return line. The oil suction assembly at least partially conveys the lubricating oil in the oil collecting tank 40 back to the dual-mode fluorine pump refrigerating assembly through the oil return pipeline, so that the lubricating oil in the oil-liquid mixture is recovered.

In the example shown in fig. 4, the tank body 30 of the liquid storage tank 3 is also provided with an oil return port at the top. A first part of an oil pipe 32 of the liquid storage tank 3 extends out of the top of the tank body 30, a second part of the oil pipe 32 extends into the tank body 30 from the outside of the tank body 30 through the oil return opening, and a pipe orifice of the second part of the oil pipe 32 is communicated with an oil return hose 35.

In some embodiments, at least one of a second throttling element, a switching unit and a second one-way unit is further provided on the oil return line. A second throttling element such as a capillary tube 11, a switching unit such as an electromagnetic valve 10, and a second check unit such as a second check valve (e.g., check valve B) 9.

And under the condition that the second one-way unit is arranged on the oil return pipeline, the oil absorption assembly can be communicated to an inlet of the second one-way unit. An outlet of the second unidirectional unit is communicated to an air suction port of the compressor 1.

As shown in fig. 2 and 3, the dual-mode fluorine pump refrigeration system further includes: a second check valve (e.g., check valve B)9, a solenoid valve 10, and a capillary tube 11.

Wherein, the pipeline where the oil pipe 32 of the liquid storage tank 3 is located is communicated to the pipeline where the inlet of the second check valve (such as the check valve B)9 is located after passing through the pipeline where the capillary tube 11 is located and the pipeline where the electromagnetic valve 10 is located. The outlet of the second check valve (such as check valve B)9 is connected to the inlet of the compressor 1. The pipeline of the port C of the four-way valve 4 is communicated to the pipeline of the inlet of the throttle valve 5. The outlet of the throttle valve 5 is connected to the inlet of a second heat exchanger (e.g. evaporator) 7. The pipeline where the outlet of the second heat exchanger (such as an evaporator) 7 is located is communicated to the pipeline where the air suction port of the compressor 1 is located. The pipeline of the S port of the four-way valve 4 is communicated to the pipeline of the inlet of the second heat exchanger (such as an evaporator) 7. The pipeline with the E port of the four-way valve 4 is communicated to the pipeline with the inlet of the fluorine pump 6. The outlet of the fluorine pump 6 is connected to the inlet of a second heat exchanger (e.g., an evaporator) 7.

Specifically, in the example shown in fig. 2 and 3, the port C of the four-way valve 4 is connected to the inlet of the throttle valve 5, and the port E of the four-way valve 4 is connected to the inlet of the fluorine pump 6. The S port of the four-way valve 4, the throttle valve 5 and the outlet of the fluorine pump 6 are commonly connected to the inlet of a second heat exchanger (e.g., evaporator) 7, and the outlet of the second heat exchanger (e.g., evaporator) 7 is connected to the suction port of the compressor 1 and the inlet of a first check valve (e.g., check valve a) 8. An outlet of an oil pipe 32 of the liquid storage tank 3 is connected to a capillary tube 11 for oil return, an outlet of the capillary tube 11 is connected to an inlet of an electromagnetic valve 10, an inlet of the electromagnetic valve 10 is connected to an inlet of a second check valve (such as a check valve B)9, and an outlet of the second check valve (such as a check valve B)9 is connected between an air suction port of the compressor 1 and an outlet of the second heat exchanger (such as an evaporator) 7.

In the example shown in fig. 2, the refrigerant is discharged from the discharge port of the compressor 1, passes through the first heat exchanger (e.g., a condenser) and the receiver 3, enters the D port of the four-way valve 4, is discharged from the C port of the four-way valve 4, passes through the throttle valve 5 and the second heat exchanger (e.g., an evaporator) 7, and then returns to the suction port of the compressor 1.

In the example shown in fig. 3, the fluorine pump 6 is activated to pump the liquid refrigerant in the liquid storage tank 3, so that the liquid refrigerant in the liquid storage tank 3 flows into the inlet of the four-way valve 4 through the outlet pipe 33 of the liquid storage tank 3, and further flows into the inlet of the fluorine pump 6 through the port E of the four-way valve 4, and the pumped liquid refrigerant flows out through the outlet of the fluorine pump 6, then flows through the second heat exchanger (e.g. evaporator) 7, the first one-way valve (e.g. one-way valve a)8 and the first heat exchanger (e.g. condenser) 2, and then flows back into the tank 30 of the liquid storage tank 3 through the inlet pipe 31 of the liquid storage tank 3. In the example shown in fig. 3, the heat pipe circulation method is a separate heat pipe circulation method, and the specific circulation path is as follows: the fluorine pump 6 → the second heat exchanger (e.g., evaporator) 7 (evaporation stage) → the first check valve (e.g., check valve a)8 → the first heat exchanger (e.g., condenser) 2 (condensation stage) → the liquid storage tank 3 → the four-way valve 4 → the fluorine pump 6.

In some embodiments, the oil absorption assembly comprises: an oil sucking member such as an oil sucking ball 36, and a hose such as an oil return hose 35.

Wherein, the oil suction piece can float on the lubricating oil in the oil collecting tank 40 and at least partially suck the lubricating oil in the oil collecting tank 40. One port of the hose is communicated to the inside of the oil suction piece and can at least partially convey the lubricating oil sucked by the oil suction piece to the oil return assembly. The other port of the hose communicates to an internal port of the tubing 32. The internal port of the oil pipe 32 is one of the two ports of the oil pipe 32 near the balance hole 34.

Therefore, lubricating oil can be collected in the oil collecting tank 40 through the oil suction piece and the hose and at least partially conveyed back to the compressor 1, so that the compressor 1 is not in oil shortage operation, and the reliability of the operation of the compressor 1 is favorably ensured.

In some embodiments, the oil absorbing member includes: an oil suction ball 36. The oil suction ball 36 is a hollow ball, and more than one oil passing hole is opened on the hollow ball, so that the lubricating oil in the oil collecting tank 40 can enter the inside of the oil suction ball 36 at least partially through the oil passing holes. The hose communicates to the inside of the oil suction ball 36.

In the example shown in fig. 4, the oil sump 40 can accommodate lubricating oil therein. Inside the oil collection tank 40, an oil suction ball 36 is provided. The suction ball 36 can float on the lubricating oil inside the sump tank 40. The top of the oil collecting tank 40 is provided with a balance hole 34, and the oil return hose 35 is connected with the nozzle of the second part of the oil pipe 32 and the oil suction ball 36 through the balance hole 34.

The oil suction ball 36 has a low density and can float on the surface of the lubricating oil in the oil collection tank 40. The oil absorption ball 36 can be made of light plastic, rubber and other materials and made into a hollow ball. On the ball wall of the hollow ball, a plurality of oil inlet small holes are arranged inside and outside in a penetrating way, and the oil return hose 35 can be connected to the inside of the oil suction ball 36. Thus, the oil suction ball 36 mainly floats on the liquid level of the lubricating oil in the oil collection tank 40, and the lubricating oil can enter the oil suction ball 36 through the small hole on the oil suction ball 36 because the density of the lubricating oil is less than that of the liquid refrigerant, so that the lubricating oil can reach the pipe orifice of the oil return hose 35, and the oil return hose 35 is ensured to absorb the liquid rich in the lubricating oil.

In some embodiments, the number of float plug assemblies is more than one. The number of the oil collecting holes at the bottom of the oil collecting tank 40 is the same as that of the floating plug assemblies. That is, at the bottom of the oil collecting tank 40, oil collecting holes are opened in the same number as the floating plug assemblies. Each of the float plug assemblies comprising: a stop 37, a floating plug rod 38 and a floating plug 39.

Wherein the stopper 37 is arranged on the top of the floating plug rod 38 and is positioned inside the oil collecting tank 40. The floating plug 39 is located at the bottom of the floating plug rod 38 and outside the oil collecting tank 40. The floating plug rod 38 penetrates through the oil collecting hole, and can cooperate with the change of buoyancy of lubricating oil in the oil-liquid mixture in the tank body 30 and buoyancy of liquid refrigerant, the stop block 37 and the floating plug 39 float up and down in the corresponding oil collecting hole, so that the lubricating oil after layering in the oil-liquid mixture in the tank body 30 is collected to the inside of the oil collecting tank 40 through the corresponding oil collecting hole at least partially.

In the example shown in fig. 4, the number of the floating plug assemblies is two, and the two floating plug assemblies have the same structure. Each float assembly comprising: a stop 37, a floating plug rod 38 and a floating plug 39. The stopper 37 is provided on the top of the floating plug rod 38, and the floating plug 39 is provided on the bottom of the floating plug rod 38.

In some embodiments, the number of float plug assemblies is two. Two of the floating plug assemblies are symmetrically arranged relative to the central axis of the oil collecting tank 40.

In the example shown in fig. 4, 2 oil collecting holes are formed in the bottom of the oil collecting tank 40 at positions symmetrical to each other. In each float assembly, the stop 37 is located inside the oil sump 40 and the stop 37 cannot pass through the corresponding oil collection hole to the outside of the oil sump 40. In each floating plug assembly, the floating plug rod 38 passes through the corresponding oil collecting hole, the top of the floating plug rod 38 is arranged inside the oil collecting tank 40, and the top of the floating plug rod 38 is connected with a stop 37, and the stop 37 is used for preventing the floating plug 38 from sliding out of the oil collecting hole. The bottom of the floating plug rod 38 is outside the oil collecting tank 40, and the bottom of the floating plug rod 38 is connected with the floating plug 39.

In some embodiments, in the case where the stopper 37 and the floating plug 39 are horizontally disposed and the floating plug rod 38 is vertically disposed, the cross-sectional area of the stopper 37 is larger than that of the floating plug rod 38, and the cross-sectional area of the stopper 37 is smaller than that of the floating plug 39.

Wherein the density of the lubricating oil in the oil-liquid mixture in the tank body 30 is between the density of the oil collecting tank 40 and the density of the floating plug rod 38, after the oil-liquid mixture in the tank body 30 is layered, if the thickness of the layered lubricating oil layer is smaller than the set minimum thickness, the oil collecting tank 40 is close to the layered liquid refrigerant. If the thickness of the layered lubricating oil layer is increased, the oil collecting tank 40 is far away from the layered liquid refrigerant and is close to or even enters the layered lubricating oil layer.

When the floating plug rod 38 moves down to the set lowest limit, the stop 37 is clamped at the upper part of the corresponding oil collecting hole to prevent the floating plug rod 38 from falling out of the bottom of the oil collecting tank 40.

When the floating plug rod 38 moves up to the set uppermost limit, the upper surface of the floating plug 39 is attached to the bottom of the oil collecting tank 40, and the floating plug 39 completely blocks the corresponding oil collecting hole, so as to prevent the liquid refrigerant inside the tank 30 from entering the oil collecting tank 40.

In the example shown in fig. 4, the area of the floating plug 39 is larger than the area of the stopper 37 and further larger than the area of the cross section of the floating plug rod 38, so that the floating plug rod 38 can move up and down. Because the density of the oil is between that of the oil sump 40 and that of the float rod 38, the oil sump 40 rises more as the thickness of the oil increases. When the thickness of the lubricating oil is insufficient, the oil collecting tank 40 cannot be floated higher, the oil collecting tank 40 is closer to the liquid level of the refrigerant, the oil collecting tank 40 descends relative to the floating plug rod 38, and the floating plug rod 38 moves upwards relative to the oil collecting tank 40, and moves downwards.

When the floating plug rod 38 moves down to the maximum, the stopper 37 connected to the top of the floating plug rod 38 is clamped on the upper part of the corresponding oil collecting hole. The stopper 37 is designed to prevent the floating plug rod 38 from coming off the oil collecting tank 40, and is equivalent to a clamping strip, so that the stopper 37 does not completely block the corresponding oil collecting hole, when the stopper 37 connected to the top of the floating plug rod 38 is clamped on the upper part of the corresponding oil collecting hole, the stopper 37 cannot completely block the oil collecting hole, and the lubricating oil floating on the liquid level of the refrigerant can enter the oil collecting tank 40. When the floating plug rod 38 moves up to the maximum, the large-area upper surface of the floating plug 39 is attached to the bottom surface of the oil collecting tank 40, and the floating plug 39 completely blocks the oil collecting hole to prevent the liquid refrigerant from entering the oil collecting tank 40.

In some embodiments, the stopper 37 and the floating plug 39 are both disc-shaped in shape in the plane of the layer of lubricating oil.

In the example shown in fig. 4, it is preferable that the stopper 37 and the floating plug 39 are both plate-shaped structures or strip-shaped structures, and the stopper 37 and the floating plug 39 are horizontally arranged in parallel at the top and bottom of the floating plug rod 38, and the floating plug rod 38 is vertically arranged. More preferably, the floating plug 39 is in a disc shape, and the stopper 37 is also in a disc shape, so that the central point can be easily found by the disc-shaped arrangement, and the floating plug rod 38 is easily centered and vertically upwards and is not easy to incline.

In some embodiments, one or more through holes penetrating in the moving direction of the float plug rod 38 are provided in the stopper 37 to increase the oil passing area of the lubricating oil inside the oil collecting tank 40.

In the example shown in fig. 4, it is preferable that the stopper 37 further has a plurality of through holes penetrating in the vertical direction, which is advantageous for increasing the oil passing area, so that when the stopper 37 is attached to the inner bottom surface of the oil collection tank 40, the lubricating oil can enter the oil collection tank 40 through the plurality of through holes of the stopper 37.

The following is a description of the specific process of the oil return control scheme of the dual-mode refrigeration system in the scheme of the present invention.

In some embodiments, in the case where the density of the lubricating oil is less than the density of the liquid refrigerant in the dual-mode refrigeration system, the tank density of the oil sump 40, the density of the lubricating oil, the density of the floating plug 39, and the density of the liquid refrigerant increase in order.

In the first case: when the density of the lubricating oil < the density of the liquid refrigerant under low temperature conditions, it is necessary to make the densities of the parts of the oil storage tank 3 meet the following requirements: tank density of the oil trap 40 < density of the lubricating oil < density of the floating plug 39 < density of the liquid refrigerant. Of course, different lubricants and refrigerants have different corresponding low temperature conditions, and the low temperature condition referred to herein is a low temperature condition matched to the lubricant and the refrigerant. The density of the components of the oil storage tank 3 may be set by materials (e.g., materials of different densities), or may be set by structures, for example, the components may be made into a closed hollow form to reduce the density.

Under the condition of low temperature, under the condition that the density of the oil collecting tank 40 is less than that of the lubricating oil, less than that of the floating plug 39 is less than that of the liquid refrigerant, when the liquid in the liquid storage tank 3 is in standing state and oil liquid layering occurs, the lubricating oil is on the upper layer surface, and the liquid refrigerant is on the lower layer of the bottom. In the receiver 3 shown in fig. 4, the interior of the oil collection tank 40 is the lubricating oil and the bottom of the oil collection tank 40 is the lubricating oil and liquid refrigerant. The lubricating oil at the bottom of the oil collecting tank 40 is floating oil floating on the liquid refrigerant, and a transitional oil mixing layer is also arranged between the lubricating oil and the liquid refrigerant.

When the thickness of the lubricant layer is larger (e.g., the thickness of the lubricant layer is greater than or equal to a predetermined thickness), the oil collecting tank 40 floats on the lubricant layer but the bottom thereof sinks into the lubricant layer due to gravity. By the same token, the floating plug 39 sinks in the liquid refrigerant, and at this time, the floating plug 39 separates from the lower surface of the oil collection tank 40, and the lubricating oil (lubricating oil) enters the oil collection tank 40 through the oil collection hole.

When the thickness of the lubricating oil layer is smaller (for example, the thickness of the lubricating oil layer is smaller than a set thickness), the upper surface of the floating plug 39 cannot be effectively separated from the lower surface of the oil collecting tank 40 (namely, the bottom outer bottom surface of the oil collecting tank 40), which means that the oil collecting hole is blocked, and a large amount of oil cannot enter the oil collecting tank 40, which means that excessive lubricating oil is not accumulated in the liquid storage tank 3, and the reliability of the starting operation of the compressor 1 is high.

In some embodiments, in the case where the density of the lubricating oil is greater than the density of the liquid refrigerant in the dual-mode refrigeration system, the density of the liquid refrigerant, the density of the tank body of the oil sump 40, the density of the lubricating oil, and the density of the floating plug 39 increase in order.

In the second case: when the density of the lubricating oil > that of the liquid refrigerant under low temperature conditions, it is necessary to make the density of the parts of the oil storage tank 3 meet the following requirements: density of liquid refrigerant < tank density of the oil trap 40 < density of the lubricating oil < density of the floating plug 39.

Under the condition of low temperature, when the density of the liquid refrigerant is less than the density of the oil collecting tank 40 and less than the density of the lubricating oil is less than the density of the floating plug 39, and the liquid in the liquid storage tank 3 is still standing to cause the phenomenon of oil liquid stratification, the lubricating oil is on the lower layer of the bottom, and the liquid refrigerant is on the upper layer of the surface.

When the thickness of the lubricating oil layer is large, the oil collecting tank 40 floats on the lubricating oil layer and the bottom of the oil collecting tank 40 is lower than the liquid refrigerant layer, and meanwhile, the bottom of the oil collecting tank 40 sinks in the lubricating oil layer due to the action of gravity. By the same token, the floating plug 39 sinks into the lubricant in the bottom layer, and the floating plug 39 separates from the lower surface of the oil collection tank 40, and the lubricant enters the oil collection tank 40 through the oil collection hole.

When the thickness of the lubricating oil layer is smaller, the upper surface of the floating plug 39 and the lower surface (outer bottom surface) of the oil collecting tank 40 cannot be effectively separated, which means that the oil collecting hole is blocked, and a large amount of oil cannot enter the oil collecting tank 40, which indicates that no excessive lubricating oil is accumulated in the liquid storage tank 3, and the reliability of the starting operation of the compressor 1 is higher.

The tank density of the oil collecting tank 40 can be set by at least one of the material and/or structure of the tank of the oil collecting tank 40. The density of the floating plug 39 can be set by at least one of the material and the structure of the floating plug 39.

In the related scheme, when the dual-mode fluorine pump refrigerating system works, the liquid storage tank is easily influenced by pressure fluctuation, liquid level fluctuation and the like, and the continuity and the reliability of oil return are poor. According to the scheme of the invention, the density difference principle can be utilized, parts and components are designed by adopting materials with different densities for collecting and separating lubricating oil, and the reliable oil return function is realized by combining with an oil return control system, so that the structure is simple, and the control is reliable. Therefore, the oil is separated by using the density difference and then stored, and then the separated lubricating oil is directly pumped, and the oil return control system is not easy to be fluctuated by the liquid level. Specifically, the collection may be performed after the apparatus is stopped and left still.

According to the scheme, different parts of the oil collecting tank in the liquid storage tank are made of materials with different densities aiming at the liquid storage tank in the dual-mode fluorine pump refrigerating system, so that the sinking depths of the floating plug in the floating plug assembly in the liquid with different densities are different, and the oil collecting tank is opened or closed. When the thickness of the lubricating oil layer is larger, the floating plug is separated from the tank body of the oil collecting tank so as to be opened, and the lubricating oil enters the oil collecting tank. When the thickness of the lubricating oil layer is smaller, the floating plug is tightly attached to the tank body of the oil collecting tank, and lubricating oil is not easy to enter the oil collecting tank. The thickness of the lubricating oil layer is dependent on the density and volume of the selected floating plug, the structural form and the like, and is dependent on the specific design choice and the calculation result. Wherein, the density of the oil collecting tank body < the density of the lubricating oil < the density of the floating plug < the density of the liquid refrigerant. Or the density of the liquid refrigerant < the density of the tank body of the oil collecting tank < the density of the lubricating oil < the density of the floating plug.

By adopting the technical scheme of the invention, different parts (such as the oil collecting tank and the floating plug assembly) of the liquid storage tank are manufactured by using materials with different densities, so that the arrangement of the tank body density of the oil collecting tank and the density of the floating plug assembly is realized, the separation of lubricating oil and liquid refrigerant is realized by using the density difference of the lubricating oil and the liquid refrigerant, and the collection of the lubricating oil is realized, so that the parts of the liquid storage tank which are manufactured by using the materials with different densities can collect and recycle part of the lubricating oil when oil is layered in the liquid storage tank, and the reliability of the refrigeration operation of the compressor is favorably improved.

According to the embodiment of the invention, the machine room air conditioner corresponding to the oil return device of the dual-mode fluorine pump refrigerating system is also provided. The machine room air conditioner may include: the oil return device of the double-mode fluorine pump refrigerating system is described above.

Since the processes and functions implemented by the air conditioner in the room of this embodiment basically correspond to the embodiments, principles and examples of the apparatus, reference may be made to the related descriptions in the foregoing embodiments for details that are not described in detail in the description of this embodiment, and no further description is given here.

By adopting the technical scheme of the invention, different parts (such as the oil collecting tank and the floating plug assembly) of the liquid storage tank are manufactured by using materials with different densities, so that the density of the tank body of the oil collecting tank and the density of the floating plug assembly are set, the separation of lubricating oil and liquid refrigerant is realized by using the density difference of the lubricating oil and the liquid refrigerant, the collection of the lubricating oil is realized, the problems of the separation and the collection of the lubricating oil when the oil in the liquid storage tank is layered under the low-temperature condition of the dual-mode fluorine pump refrigerating system can be solved, and the dual-mode fluorine pump refrigerating system has the advantages of simple structure and good reliability.

According to the embodiment of the invention, a control method of the oil return device of the dual-mode fluorine pump refrigeration system corresponding to the machine room air conditioner is also provided, as shown in a flow chart of an embodiment of the method shown in fig. 5. The control method of the oil return device of the dual-mode fluorine pump refrigeration system can comprise the following steps: step S110 to step S130.

At step S110, the operating mode of the dual mode fluorine pump refrigeration system is determined. The operation mode of the double-mode fluorine pump refrigerating system is a refrigerating mode or a fluorine pump mode.

At step S120, in a case that the dual-mode fluorine pump refrigeration system operates in the refrigeration mode, determining an oil temperature superheat degree of a compressor in the dual-mode fluorine pump refrigeration system (for example, determining the oil temperature superheat degree of the compressor 1), or determining a time length during which the dual-mode fluorine pump refrigeration system does not perform oil return control, and determining whether an oil return operation needs to be performed according to the oil temperature superheat degree of the compressor in the dual-mode fluorine pump refrigeration system or the time length during which the dual-mode fluorine pump refrigeration system does not perform oil return control. And if the oil return operation needs to be executed, controlling the pipeline where the oil return assembly is located to be communicated. And if the oil return operation is not required to be executed, controlling the pipeline where the oil return assembly is located to be closed. Of course, if the oil return operation needs to be executed, the pipeline where the oil return assembly is located can be controlled to be communicated or communicated and throttled. And if the oil return operation is not required to be executed, controlling the pipeline where the oil return assembly is located to be closed or not closed but throttled.

In step S130, in the case that the dual-mode fluorine pump refrigeration system operates in the fluorine pump mode, the pipeline where the oil return component is located is controlled to be closed, so as to prevent the refrigerant at the outlet of the evaporator in the dual-mode fluorine pump refrigeration system from returning to the liquid storage tank 3.

In the scheme of the invention, the oil return control process of the dual-mode fluorine pump refrigerating system can comprise the following processes:

first oil return condition: under the normal compressor 1 refrigeration mode, lubricating oil can have stable backward flow, can not appear fluid layering phenomenon in the liquid storage pot 3, but the fluid layering just can appear in the too long fluid storage pot 3 of down time. Therefore, at the start stage of the compressor 1, the operation of the compressor 1 can be controlled according to the superheat degree of the oil temperature of the compressor 1 to prevent the oil-starved operation of the compressor 1.

When the oil temperature superheat degree of the compressor 1 is high (for example, the oil temperature superheat degree of the compressor 1 is greater than or equal to a set superheat degree) or oil return control is not performed for a long time (for example, the time when the oil return control is not performed by the compressor 1 is greater than or equal to a set operation time), the lubricating oil is likely to be insufficient, oil return operation needs to be performed, at this time, the electromagnetic valve 10 is opened, and then the lubricating oil (lubricating oil) in the oil collecting tank 40 passes through the capillary tube 11 under the action of high-low pressure difference, and returns to the compressor 1 after passing through the electromagnetic valve 10 and the second one-way valve (for example, the one-way valve B) 9. Of course, the opening time and duration of the solenoid valve 10 are related to the magnitude of the pressure difference, the specific type of the compressor 1, the design of the system pipeline, and other factors, and can be determined according to experimental conditions.

Second oil return situation: when the fluorine pump mode is started (i.e. the fluorine pump mode when the compressor 1 is closed and the fluorine pump 6 is started), the second check valve (e.g. the check valve B)9, the solenoid valve 10 and the capillary tube 11 can prevent the refrigerant at the outlet of the second heat exchanger (e.g. the evaporator) 7 from bypassing and returning to the liquid storage tank 3 on the pipeline where the second heat exchanger (e.g. the evaporator) is located, thereby ensuring that the sufficient refrigerant flow passes through the first heat exchanger (e.g. the condenser) 2.

Since the processing and functions implemented by the method of this embodiment basically correspond to the embodiments, principles and examples of the air conditioner in the machine room, reference may be made to the related descriptions in the foregoing embodiments without being detailed in the description of this embodiment.

Adopt the technical scheme of this embodiment, through the different spare parts (like oil collecting tank and floating plug subassembly) that utilize the material preparation liquid storage pot of different densities to the setting of the jar body density of oil collecting tank and floating plug subassembly density is realized, and then the density difference of utilizing lubricating oil and liquid refrigerant, the separation to lubricating oil and liquid refrigerant is realized, and the realization is to the collection of lubricating oil, can solve the oil return control problem that the lubricating oil of separation collection returns the compressor, can prevent that the compressor from lacking the oil operation, promote compressor operational reliability.

In summary, it is readily understood by those skilled in the art that the advantageous modes described above can be freely combined and superimposed without conflict.

The above description is only an example of the present invention, and is not intended to limit the present invention, and it is obvious to those skilled in the art that various modifications and variations can be made in the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.

Claims

1. The oil return device of the double-mode fluorine pump refrigerating system is characterized in that the double-mode fluorine pump refrigerating system can operate in a refrigerating mode or a fluorine pump mode; the oil return device of the double-mode fluorine pump refrigerating system comprises: the double-mode fluorine pump refrigerating assembly, the liquid storage tank (3) and the oil return assembly; the liquid storage tank (3) comprises: the oil collection tank comprises a tank body (30), an oil collection tank (40), an oil absorption assembly and a floating plug assembly; wherein the content of the first and second substances,

the liquid storage tank (3) is communicated with the dual-mode fluorine pump refrigerating assembly; the oil collecting tank (40) is arranged in the tank body (30);

the oil suction assembly is arranged inside the oil collecting tank (40) and can be communicated to the oil return assembly;

the floating plug assembly is arranged at the bottom of the oil collecting tank (40), a first part of the floating plug assembly is positioned in the oil collecting tank (40), and a second part of the floating plug assembly can extend out of the bottom of the oil collecting tank (40); fluid mixture in the jar body (30) includes: lubricating oil and liquid refrigerant;

the oil collecting tank (40) can float in a lubricating oil layer formed after the oil-liquid mixture is layered, and the bottom of the oil collecting tank (40) can be completely immersed in the lubricating oil layer or partially immersed in a liquid refrigerant layer; as the thickness of the lubricating oil layer changes, the first part and the second part of the floating plug assembly float up and down to enable lubricating oil in the lubricating oil layer to be at least partially collected into the oil collecting tank (40);

the oil suction component floats on the lubricating oil in the oil collecting tank (40), at least partially sucks the lubricating oil, and then the lubricating oil is conveyed back to the double-mode fluorine pump refrigerating component through the oil return component.

2. The oil return arrangement for a dual mode fluorine pump refrigeration system of claim 1 wherein said dual mode fluorine pump refrigeration assembly comprises: the system comprises a compressor (1), a first heat exchanger (2), a four-way valve (4), a first throttling element, a fluorine pump (6), a second heat exchanger (7) and a first one-way unit;

the liquid storage tank (3) is provided with a first inlet and outlet pipe, an oil pipe (32) and a second inlet and outlet pipe; the first inlet and outlet pipe and the second inlet and outlet pipe can extend into the oil liquid mixture in the tank body (30) and can extend into the layered liquid refrigerant; when one of the first inlet and outlet pipe and the second inlet and outlet pipe is an inlet pipe, the other one is an outlet pipe;

the top of the oil collecting tank (40) is provided with a balance hole (34); the oil pipe (32) is used for communicating the oil suction assembly with the oil return assembly through the balance hole (34);

the bottom of the oil collecting tank (40) is provided with an oil collecting hole; the floating plug assembly can float up and down through the oil collecting hole;

the outlet of the first unidirectional unit and the exhaust port of the compressor (1) are communicated to a first inlet and outlet pipe of the liquid storage tank (3) after passing through the first heat exchanger (2); the oil return assembly is communicated to an air suction port of the compressor (1); a second inlet and outlet pipe of the liquid storage tank (3) is communicated to a D port of the four-way valve (4); the port C of the four-way valve (4) passes through the first throttling element and the second heat exchanger (7) and then is respectively communicated to the inlet of the first one-way unit and the suction port of the compressor (1); an S port of the four-way valve (4) and outlets of the first throttling element and the fluorine pump (6) are communicated to an inlet of the second heat exchanger (7) together; and an E port of the four-way valve (4) passes through the fluorine pump (6) and the second heat exchanger (7) and is respectively communicated to an inlet of the first one-way unit and an air suction port of the compressor (1).

3. The oil return apparatus of a dual mode fluorine pump refrigeration system of claim 1, wherein the oil return assembly comprises: an oil return line; the oil suction assembly at least partially conveys lubricating oil in the oil collection tank (40) back to the dual-mode fluorine pump refrigerating assembly through the oil return pipeline, so that the lubricating oil in the oil-liquid mixture is recovered.

4. The oil return apparatus of a dual mode fluorine pump refrigeration system according to claim 3, wherein at least one of a second throttling element, a switching unit and a second check unit is further provided on the oil return line; wherein the content of the first and second substances,

under the condition that the second one-way unit is arranged on the oil return pipeline, the oil absorption assembly can be communicated to an inlet of the second one-way unit; and the outlet of the second one-way unit can be communicated to the air suction port of the compressor (1).

5. The oil return device of the dual-mode fluorine pump refrigerating system as claimed in any one of claims 1 to 4, wherein the oil suction assembly comprises: an oil absorbing member and a hose; wherein the content of the first and second substances,

the oil suction piece can float on the lubricating oil in the oil collecting tank (40) and at least partially sucks the lubricating oil in the oil collecting tank (40);

the hose is communicated to the inside of the oil suction piece and can at least partially convey the lubricating oil sucked by the oil suction piece to the oil return assembly.

6. The oil return device of the dual-mode fluorine pump refrigerating system as claimed in claim 5, wherein the oil suction member comprises: an oil suction ball (36); the oil suction ball (36) is a hollow ball, and more than one oil passing hole is formed in the hollow ball, so that lubricating oil in the oil collecting tank (40) can enter the inside of the oil suction ball (36) at least partially through the oil passing holes; the hose is communicated to the inside of the oil suction ball (36).

7. The oil return apparatus of a dual mode fluorine pump refrigeration system according to any of claims 1 to 4, wherein the number of the float plug assemblies is more than one; the number of the oil collecting holes at the bottom of the oil collecting tank (40) is the same as that of the floating plug assemblies;

each of the float plug assemblies comprising: a stop block (37), a floating plug rod (38) and a floating plug (39); wherein the content of the first and second substances,

the stop block (37) is arranged at the top of the floating plug rod (38) and is positioned inside the oil collecting tank (40); the floating plug (39) is positioned at the bottom of the floating plug rod (38) and is positioned outside the oil collecting tank (40); the floating plug rod (38) penetrates through the oil collecting hole, and can change along with the buoyancy of lubricating oil in the oil-liquid mixture in the tank body (30) and the buoyancy of liquid refrigerant, and in cooperation, the stop block (37) and the floating plug (39) float up and down in the corresponding oil collecting hole, so that the lubricating oil after layering in the oil-liquid mixture in the tank body (30) is at least partially collected to the inside of the oil collecting tank (40) through the corresponding oil collecting hole.

8. The oil return apparatus of a dual mode fluorine pump refrigeration system of claim 7 wherein the number of the float plug assemblies is two; the two floating plug assemblies are symmetrically arranged relative to the central axis of the oil collecting tank (40).

9. A oil return apparatus of a dual mode fluorine pump refrigerating system according to claim 7, wherein in a case where the stopper (37) and the floating plug (39) are horizontally disposed and the floating plug rod (38) is vertically disposed, the cross sectional area of the stopper (37) is larger than that of the floating plug rod (38), and the cross sectional area of the stopper (37) is smaller than that of the floating plug (39);

wherein the density of the lubricating oil in the oil-liquid mixture in the tank body (30) is between the density of the oil collecting tank (40) and the density of the floating plug rod (38), and after the oil-liquid mixture in the tank body (30) is layered, if the thickness of the layered lubricating oil layer is smaller than a set minimum thickness, the oil collecting tank (40) is close to the layered liquid refrigerant; if the thickness of the layered lubricating oil layer is increased, the oil collecting tank (40) is far away from the layered liquid refrigerant and is close to or even enters the layered lubricating oil layer.

10. The oil return apparatus of a dual mode fluorine pump refrigeration system of claim 9 wherein,

when the floating plug rod (38) moves downwards to a set lowest limit, the stop block (37) is clamped at the upper part of the corresponding oil collecting hole to prevent the floating plug rod (38) from falling out of the bottom of the oil collecting tank (40);

when the floating plug rod (38) moves upwards to a set uppermost limit, the upper surface of the floating plug (39) is attached to the bottom of the oil collecting tank (40), and the floating plug (39) completely blocks the corresponding oil collecting hole so as to prevent the liquid refrigerant in the tank body (30) from entering the oil collecting tank (40);

and/or the presence of a gas in the gas,

the shape of the stop block (37) and the shape of the floating plug (39) on the plane where the lubricating oil layer is located are both disc-shaped.

11. A oil return apparatus of a dual mode fluorine pump refrigerating system according to claim 9, wherein one or more through holes penetrating in a moving direction of the floating plug rod (38) are provided on the stopper (37) to increase an oil passing area of the lubricating oil inside the oil collecting tank (40).

12. A oil return apparatus for a dual mode fluorine pump refrigeration system according to any of claims 7 to 11, wherein,

in the case where the density of the lubricating oil in the dual-mode refrigeration system is less than that of the liquid refrigerant, the tank body density of the oil collecting tank (40), the density of the lubricating oil, the density of the floating plug (39) and the density of the liquid refrigerant increase in sequence;

in the case that the density of the lubricating oil in the dual-mode refrigeration system is greater than that of the liquid refrigerant, the density of the tank body of the oil collecting tank (40), the density of the lubricating oil and the density of the floating plug (39) are increased in sequence;

wherein the tank body density of the oil collecting tank (40) can be set by at least one of the material and/or the structure of the tank body of the oil collecting tank (40); the density of the floating plug (39) can be set by at least one of the material and/or structure of the floating plug (39).

13. A machine room air conditioner, comprising: the oil return arrangement for a dual mode fluorine pump refrigeration system as claimed in any one of claims 1 to 12.

14. A control method of an oil return device of a dual mode fluorine pump refrigeration system according to any one of claims 1 to 12, comprising:

step S110, determining the operation mode of the dual-mode fluorine pump refrigerating system; the operation mode of the double-mode fluorine pump refrigerating system is a refrigerating mode or a fluorine pump mode;

step S120, under the condition that the dual-mode fluorine pump refrigerating system operates in a refrigerating mode, determining the oil temperature superheat degree of a compressor in the dual-mode fluorine pump refrigerating system, or determining the duration of the dual-mode fluorine pump refrigerating system without oil return control, and determining whether oil return operation needs to be executed or not according to the oil temperature superheat degree of the compressor in the dual-mode fluorine pump refrigerating system or the duration of the dual-mode fluorine pump refrigerating system without oil return control; if oil return operation needs to be executed, controlling a pipeline where the oil return assembly is located to be communicated; if the oil return operation is not required to be executed, controlling a pipeline where the oil return assembly is located to be closed;

and S130, under the condition that the dual-mode fluorine pump refrigerating system operates in a fluorine pump mode, controlling a pipeline where the oil return component is located to be closed so as to prevent the refrigerant at the outlet of the evaporator in the dual-mode fluorine pump refrigerating system from returning to the liquid storage tank (3).