CN216203954U - Air conditioning system - Google Patents

Abstract

The present application provides an air conditioning system. The air conditioning system comprises a compressor (1), a condenser (2), a throttling device (3) and an evaporator (4), wherein the evaporator (4) comprises a vertical gas collecting pipe (5), the top of the vertical gas collecting pipe (5) is connected to an air suction port of the compressor (1) through an air suction pipe (6), a liquid return pipe (7) is arranged at the bottom of the vertical gas collecting pipe (5), the other end of the liquid return pipe (7) is connected to the air suction pipe (6), a control valve (8) is arranged on the liquid return pipe (7), and the liquid return pipe (7) is opened by the control valve (8) when the air conditioning system reaches a preset condition. According to the air conditioning system, the problem that the refrigerant liquid at the bottom of the evaporator directly returns to the air suction pipe of the compressor through the oil return pipe easily or even reaches the oil tank of the compressor can be effectively solved, and the compressor is started with liquid and is easy to liquid impact in the next starting process.

Description

Air conditioning system

Technical Field

The application relates to the technical field of refrigeration, in particular to an air conditioning system.

Background

In the current steam compression type refrigeration cycle, a compressor is an important part and is used as a power source for flowing of a refrigerant in the system cycle, and the compressors in most refrigeration cycles need sufficient lubrication, so that the lubrication of moving parts such as a crankshaft, a bearing, a connecting rod and the like is ensured, and the sealing of a moving surface in a compression chamber can be enhanced.

But lubricating oil and refrigerant have phenomena such as intersolubility, separation, stay lubricating oil easily in the refrigerating system, often can't realize sufficient lubricating oil backward flow in some abominable operating condition, lead to the compressor to lack oil operation, and then cause efficiency to descend, the compressor is overheated the card jar easily and damages etc..

The reasons for unsmooth oil return are many, for example, the structural design has an oil return dead angle, the low flow rate of the low-frequency operation refrigerant cannot carry more oil to return to the compressor, the flow rate and the oil return of the bottom branch are insufficient due to the excessively high gas collecting pipe, and the like.

In the design of a common air-conditioning refrigeration system, an oil separator is adopted to separate lubricating oil in high-pressure exhaust in advance, and the separated lubricating oil is led to return to an air suction pipeline of a compressor in advance under the action of high-pressure and low-pressure differential pressure through structures such as an oil return capillary tube and the like, so that the amount of the lubricating oil flowing in the refrigeration system is very small.

However, in an air conditioning refrigeration system without an oil separator, how to achieve safe oil return is a significant problem to be considered by system and structure designers. In an air-conditioning refrigeration system which does not adopt a gas-liquid separator, the prevention of liquid impact of a compressor is also an important problem, refrigerant liquid which is not completely evaporated in an evaporator enters the compressor along with high-speed refrigerant gas, and the liquid impacts the compressor to easily cause damage.

In order to prevent the liquid refrigerant in the evaporator from entering the compressor, the return air header is usually connected above the highest possible liquid level in the gas collecting header of the evaporator, but this easily causes the liquid refrigerant and the lubricating oil to be easily reserved at the bottom of the gas collecting header, because the refrigerant flow of the bottom branch is small and the flow rate is low, the refrigerant cannot carry enough liquid refrigerant and/or lubricating oil to flow upwards, and after the operation time is too long, the liquid refrigerant and the retained part of the lubricating oil are easily accumulated at the bottom of the gas collecting header. When the liquid heights gradually rise, the liquid seal is easily formed on the bottom branches, and the flow of the refrigerant capable of passing through is less, so that the phenomenon of liquid storage at the bottom of the evaporator is caused.

In the prior art, a gas collecting tube assembly is proposed, in which an oil return tube is connected to a gas return main at the bottom of the gas collecting tube assembly of an evaporator, and liquid remaining at the bottom of the gas collecting tube is sucked and returned to a compressor by a pressure difference. However, after the air-conditioning refrigeration system is stopped and stands still, the high pressure and the low pressure of the air-conditioning refrigeration system can gradually realize pressure balance, the high pressure end can extrude liquid refrigerant to be accumulated towards the evaporator, the refrigerant liquid at the bottom of the evaporator easily directly returns to the air suction pipe of the compressor through the oil return pipe and even reaches the oil tank of the compressor, and the liquid-carrying starting, the liquid impact and the like of the compressor can be caused in the next starting process.

SUMMERY OF THE UTILITY MODEL

Therefore, the technical problem to be solved in the present application is to provide an air conditioning system, which can effectively solve the problem that the refrigerant liquid at the bottom of the evaporator is easy to directly return to the air suction pipe of the compressor through the oil return pipe, and even reaches the oil tank of the compressor, and the compressor is started with liquid and easy to be subjected to liquid impact in the next starting process.

In order to solve the above problem, the present application provides an air conditioning system, including compressor, condenser, throttling arrangement and evaporimeter, the evaporimeter includes vertical collecting pipe, and the top of vertical collecting pipe is connected to the induction port of compressor through the breathing pipe, and the bottom of vertical collecting pipe is provided with back the liquid pipe, and the other end that returns the liquid pipe is connected to the breathing pipe, is provided with the control valve on returning the liquid pipe, and the control valve opens back the liquid pipe when air conditioning system reaches preset condition.

Preferably, the liquid return pipe comprises a reserved section located in the suction pipe, and the reserved section extends along the flowing direction of the refrigerant.

Preferably, the reserve section is arranged coaxially with the suction pipe.

Preferably, the liquid return pipe is positioned in the part of the vertical gas collecting pipe, the distance between the inlet end and the pipe bottom of the vertical gas collecting pipe is h, and h is more than 0.

Preferably, the control valve is a solenoid valve.

Preferably, a one-way valve is arranged on a pipeline between the control valve and the vertical gas collecting pipe.

Preferably, the air conditioning system further comprises an oil separator and a capillary section, one end of the capillary section is connected to an oil return port of the oil separator, and the other end of the capillary section is connected to a liquid return pipe between the solenoid valve and the one-way valve.

Preferably, the preset condition is that the pressure difference between the vertical gas collecting pipe and the gas suction pipe reaches a preset value.

Preferably, the preset condition is that the air conditioning system reaches an oil return condition.

Preferably, the liquid return pipe is welded and sealed with the bottom of the vertical gas collecting pipe; and/or, the liquid return pipe and the air suction pipe are welded and sealed.

Preferably, the evaporator further comprises a liquid separation head and a liquid separation branch pipe, the liquid separation head is connected with the throttling device, and the liquid separation branch pipe is respectively connected with the liquid separation head and the evaporator.

Preferably, the condenser comprises a liquid collecting pipe and a gas distributing pipe, the gas distributing pipe is connected with an exhaust port of the compressor, and the liquid collecting pipe is connected with the throttling device.

The application provides an air conditioning system, including compressor, condenser, throttling arrangement and evaporimeter, the evaporimeter includes vertical collecting pipe, and the induction port that the breathing pipe is connected to the compressor is passed through at the top of vertical collecting pipe, and the bottom of vertical collecting pipe is provided with back the liquid pipe, and the other end that returns the liquid pipe is connected to the breathing pipe, returns and is provided with the control valve on the liquid pipe, and the control valve opens back the liquid pipe when air conditioning system reaches the preset condition. This air conditioning system increases liquid return pipe in the bottom of vertical gas collecting pipe, and increase the control valve on liquid return pipe, can be at air conditioning system operation in-process, utilize the intercommunication of control valve control liquid return pipe, make the refrigerant liquid suction that vertical gas collecting pipe bottom was reserved return the induction port of compressor after atomizing, when air conditioning system shut down, utilize the control valve to make liquid return pipe close, prevent that refrigerant liquid from returning the compressor, thereby when preventing the compressor restart, produce the problem that the compressor takes liquid to start and easy liquid to hit, guarantee air conditioning system's safe and reliable operation.

Drawings

Fig. 1 is a schematic structural diagram of an air conditioning system according to an embodiment of the present application.

The reference numerals are represented as:

1. a compressor; 2. a condenser; 3. a throttling device; 4. an evaporator; 5. a vertical gas collecting pipe; 6. an air intake duct; 7. a liquid return pipe; 8. a control valve; 9. reserving a section; 10. a capillary segment; 11. a liquid separation head; 12. a branch liquid separating pipe; 13. a liquid collecting pipe; 14. a gas distributing pipe; 15. a one-way valve; 16. an oil separator.

Detailed Description

Referring to fig. 1 in combination, according to an embodiment of the present application, an air conditioning system includes a compressor 1, a condenser 2, a throttling device 3, and an evaporator 4, where the evaporator 4 includes a vertical gas collecting pipe 5, the top of the vertical gas collecting pipe 5 is connected to a suction port of the compressor 1 through a gas suction pipe 6, the bottom of the vertical gas collecting pipe 5 is provided with a liquid return pipe 7, the other end of the liquid return pipe 7 is connected to the gas suction pipe 6, the liquid return pipe 7 is provided with a control valve 8, and the control valve 8 opens the liquid return pipe 7 when the air conditioning system reaches a preset condition.

This air conditioning system increases liquid return pipe 7 in the bottom of vertical collecting pipe 5, and increase control valve 8 on liquid return pipe 7, can be in air conditioning system operation in-process, utilize the intercommunication of control valve 8 control liquid return pipe 7, make the refrigerant liquid of reserving in the bottom of vertical collecting pipe 5 pass through liquid return pipe 7 and get into in breathing pipe 6, and return the induction port of compressor 1 after breathing pipe 6 suction atomizing, when air conditioning system shuts down, utilize control valve 8 to make liquid return pipe 7 close, prevent that refrigerant liquid from returning compressor 1, thereby when preventing compressor 1 from restarting, produce the problem that compressor 1 starts with liquid and easy liquid hits, guarantee air conditioning system's safe and reliable operation.

In one embodiment, the liquid return pipe 7 comprises a reserved section 9 located inside the suction pipe 6, and the reserved section 9 extends along the flow direction of the refrigerant. Reserve section 9 and extend along the flow direction of refrigerant, can be the same with the refrigerant flow direction in the breathing pipe 6, can be more convenient under the suction effect of breathing pipe 6 by follow the suction in reserving section 9 come out, the resistance is littleer, and the suction effect is more obvious, conveniently realizes the atomizing of refrigerant more, effectively avoids liquid refrigerant directly to enter into and takes place the liquid attack phenomenon in the compressor 1. In this embodiment, the length of the reserved segment 9 is L, and L > 0. As a preferred embodiment, L.gtoreq.1 cm.

In an embodiment, the reserved section 9 and the air suction pipe 6 are coaxially arranged, so that the air suction pipe on the peripheral side of the reserved section 9 can suck the refrigerant in the reserved section 9 more uniformly, the flow of the refrigerant is more stable, and the atomization effect of the air suction pipe 6 on the refrigerant in the reserved section 9 can be further enhanced.

In one embodiment, the liquid return pipe 7 is inserted into the vertical gas collecting pipe 5 from the bottom, and the liquid return pipe 7 is located in the portion of the vertical gas collecting pipe 5, where the distance between the inlet end of the liquid return pipe 7 and the bottom of the vertical gas collecting pipe 5 is h, and h > 0, so that the inlet end of the liquid return pipe 7 is higher than the bottom of the vertical gas collecting pipe 5, and the impurities remaining at the bottom of the vertical gas collecting pipe 5 are prevented from entering the control valve 8 and causing blockage.

In one embodiment, the control valve 8 is a solenoid valve, provided that the pressure difference between the vertical gas header 5 and the gas suction pipe 6 reaches a predetermined value. In this embodiment, adopt the solenoid valve as the control valve of control liquid return pipe 7 break-make, can detect the pressure differential of the import and the export of liquid return pipe 7 through pressure sensor simultaneously, the exit pressure differential of liquid return pipe 7 that detects according to pressure sensor controls the solenoid valve, when pressure differential does not reach the default, then control solenoid valve closes liquid return pipe 7, avoid the refrigerant to take place the backward flow, when pressure differential reaches the default, then control solenoid valve opens liquid return pipe 7, make the induction port that returns the compressor after the refrigerant suction in vertical gas collecting pipe 5 atomizes, thereby effectively avoid evaporimeter and 5 bottoms of vertical gas collecting pipe to be detained the liquid problem.

In this embodiment, because the solenoid valve is active control to the on-off control of liquid return pipe 7, consequently can adjust the control threshold value of solenoid valve through the mode of adjusting preset differential pressure value, realize adjusting the liquid return of the different operating modes of air conditioning system, use more in a flexible way, and the range of application is wider, can satisfy the liquid return demand of the evaporimeter of different air conditioning systems and vertical collecting pipe 5 better, further improves the reliability of air conditioning system during operation.

In one embodiment, a check valve 15 is provided on the line between the control valve 8 and the vertical header 5.

In one embodiment, the air conditioning system further comprises an oil separator 16 and a capillary section 10, one end of the capillary section 10 is connected to an oil return port of the oil separator 16, and the other end of the capillary section 10 is connected to the liquid return pipe 7 between the solenoid valve and the check valve 15.

In the present embodiment, by connecting the capillary section 10 between the liquid return pipe 7 and the oil separator 16, the oil return of the oil separator 16 can be achieved by the capillary section 10.

For the present embodiment, it can also be considered that an oil return line formed by the control valve 8 and the capillary section 10 is used as a conventional oil return line, then on the basis of the conventional oil return line, the liquid return pipe 7 is connected between the control valve 8 and the capillary section 10, the other end of the liquid return pipe 7 is connected to the vertical gas collecting pipe 5, and the check valve 15 is additionally arranged on the liquid return pipe 7, so that the air conditioning system of the embodiment of the present application can increase the liquid return function by only adding one check valve 15 and one liquid return pipe 7, and fully utilizes the electromagnetic valve with the original oil return function, so that the cost is low, the practicability is good, and the reliability is high.

For this embodiment, the preset condition is that the air conditioning system reaches the oil return condition, and therefore, the control of the control valve 8 in this embodiment is controlled by the oil return control of the air conditioning system, and it is not necessary to additionally set an independent control system, and the oil return control of the air conditioning system itself can be utilized to return oil, and meanwhile, the liquid return control of the vertical gas collecting pipe 5 is simultaneously realized by utilizing the liquid return pipe 7, so that the structure is simpler, the control procedure is simpler, and the control is more convenient.

In this embodiment, when the solenoid valve is closed, the check valve 15 prevents the lubricant oil separated in the oil separator 16 from entering the bottom of the vertical header 5 through the capillary segment 10. At this time, the outlet of the check valve 15 is in a high pressure state (the capillary tube is not throttled when no fluid flows, and the inlet and the outlet of the capillary tube are in a pressure balance state), and the inlet of the check valve 15 is in a low pressure state, so that the check valve 15 is in a reverse cut-off closing state, and no refrigerant or lubricating oil flows.

In other embodiments, the preset condition for opening the control valve 8 may be the compressor operation frequency, the air conditioning system operation time, or other control conditions.

In one embodiment, the liquid return pipe 7 is welded and sealed with the bottom of the vertical gas collecting pipe 5; and/or, the liquid return pipe 7 is welded and sealed with the air suction pipe 6, so that the connection stability of the liquid return pipe 7 with the air suction pipe 6 and the vertical gas collecting pipe 5 is ensured on one hand, and the sealing reliability of the connection position of the liquid return pipe 7 with the air suction pipe 6 and the vertical gas collecting pipe 5 is ensured on the other hand.

In one embodiment, the evaporator 4 further comprises a liquid separation head 11 and a branch liquid separation pipe 12, wherein the liquid separation head 11 is connected with the throttling device 3, and the branch liquid separation pipe 12 is respectively connected with the liquid separation head 11 and the evaporator 4.

In one embodiment, the condenser 2 comprises a liquid collecting pipe 13 and a gas distributing pipe 14, the gas distributing pipe 14 is connected with the exhaust port of the compressor 1, and the liquid collecting pipe 13 is connected with the throttling device 3.

The above-mentioned throttle device is, for example, an expansion valve.

In this embodiment, the exhaust port of the compressor 1 is connected to the gas distribution pipe 14 of the condenser 2 through an exhaust pipe, the gas distribution pipe 14 distributes high-temperature and high-pressure refrigerant gas to each branch in the condenser 2 through a plurality of gas distribution branch pipes, phase change condensation and liquefaction are realized in the condenser 2, the refrigerant gas is collected to the liquid collection pipe 13 through the liquid collection branch pipe, the total outlet of the liquid collection pipe 13 is connected to the inlet of the throttling device 3, the outlet of the throttling device 3 is connected to the liquid distribution head 11 of the evaporator 4, and the high-pressure refrigerant is throttled, cooled and depressurized through the throttling device 3; the liquid distributing head 11 is connected with a plurality of incomplete same liquid distributing branch pipes 12, each liquid distributing branch pipe 12 distributes low-temperature and low-pressure refrigerant liquid to each branch of the evaporator 4, phase change evaporation and gasification are realized in the evaporator 4, the low-temperature and low-pressure refrigerant liquid is collected to the vertical gas collecting pipe 5 through the gas collecting branch pipe, the total outlet of the vertical gas collecting pipe 5 is connected to the gas suction pipe 6, and the gas suction pipe 6 is connected with the gas suction port of the compressor 1.

The air conditioning system is particularly suitable for air conditioners in precision rooms, wherein the compressor 1, the evaporator 4, the throttling device 3, the indoor fan and the like are usually arranged in an indoor unit, the condenser 2, the outdoor fan and the like are arranged in an outdoor unit, and the indoor unit and the outdoor unit are connected through a connecting pipe. Because the air conditioner of the precise machine room operates the refrigeration working condition all the year round, the vertical gas collecting pipe 5 of the evaporator 4 is very suitable for using the design scheme of oil return liquid at the bottom of the gas collecting pipe, the pipeline flow required to be connected by the liquid return pipe assembly is short, and the oil return control of the compressor can be realized by fully utilizing the pressure difference.

When the air conditioning system is started and operated, the electromagnetic valve is opened as required, so that liquid at the bottom of the evaporator 4 and/or the vertical gas collecting pipe 5 flows under the action of differential pressure suction, enters the gas suction pipe 6 after passing through the one-way valve 15 and the electromagnetic valve, and is atomized at an outlet and returns to the compressor 1; when the air conditioning system is stopped or liquid return and oil return are not needed, the electromagnetic valve is closed to prevent liquid from entering the suction pipe 6 of the compressor 1. Obviously, when the electromagnetic valve is opened, the normal oil return function can be realized.

When the refrigeration load is small, the compressor 1 is usually operated at a low frequency, the circulating amount of the refrigerant in the system is small, and surplus refrigerant exists, so that the time interval between oil return and liquid return can be longer. However, when the low-frequency operation time is too long, the compressor 1 may have an oil shortage problem, so that the high-frequency operation is performed to realize oil return; surplus refrigerant can be accumulated at the bottom of the evaporator 4 and/or the bottom of the vertical gas collecting pipe 5 at low frequency, and the refrigerant cannot flow to the compressor 1 because the electromagnetic valve is closed, so that proper refrigerant circulation amount is ensured during low-frequency operation, and excessive refrigerant circulation amount is avoided. Therefore, the embodiment of the application can realize the functions of liquid return and oil return at the same time, and is a better simplified control scheme.

It is readily understood by a person skilled in the art that the advantageous ways described above can be freely combined, superimposed without conflict.

The present invention is not intended to be limited to the particular embodiments shown and described, but is to be accorded the widest scope consistent with the principles and novel features herein disclosed. The foregoing is only a preferred embodiment of the present application, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present application, and these modifications and variations should also be considered as the protection scope of the present application.

Claims (12)

1. The utility model provides an air conditioning system, its characterized in that, includes compressor (1), condenser (2), throttling arrangement (3) and evaporimeter (4), evaporimeter (4) are including vertical collecting pipe (5), the top of vertical collecting pipe (5) is connected to through breathing pipe (6) the induction port of compressor (1), the bottom of vertical collecting pipe (5) is provided with returns liquid pipe (7), the other end of returning liquid pipe (7) is connected to breathing pipe (6), be provided with control valve (8) on returning liquid pipe (7), control valve (8) are in air conditioning system opens when reaching preset condition return liquid pipe (7).

2. Air conditioning system according to claim 1, characterized in that the liquid return pipe (7) comprises a reserve (9) inside the suction pipe (6), the reserve (9) extending in the direction of flow of the refrigerant.

3. Air conditioning system according to claim 2, characterized in that the reserve (9) is arranged coaxially to the suction duct (6).

4. Air conditioning system according to claim 1, wherein the liquid return pipe (7) is located in the vertical header (5) at a distance h between the inlet end and the bottom of the vertical header (5), h > 0.

5. Air conditioning system according to claim 1, characterized in that the control valve (8) is a solenoid valve.

6. Air conditioning system according to claim 5, characterized in that a non-return valve (15) is arranged on the line between the control valve (8) and the vertical header (5).

7. Air conditioning system according to claim 6, further comprising an oil separator (16) and a capillary section (10), wherein one end of the capillary section (10) is connected to an oil return of the oil separator (16), and the other end of the capillary section (10) is connected to a liquid return pipe (7) between the solenoid valve and the check valve (15).

8. Air conditioning system according to claim 5, characterized in that said preset condition is that the pressure difference between said vertical header (5) and said suction duct (6) reaches a preset value.

9. The air conditioning system of claim 7, wherein the predetermined condition is the air conditioning system reaching an oil return condition.

10. The air conditioning system as claimed in claim 1, characterized in that the liquid return pipe (7) is sealed by welding with the bottom of the vertical header (5); and/or the liquid return pipe (7) and the air suction pipe (6) are welded and sealed.

11. Air conditioning system according to claim 1, wherein said evaporator (4) further comprises a liquid separation head (11) and a liquid separation branch (12), said liquid separation head (11) being connected to said throttling means (3) and said liquid separation branch (12) being connected to said liquid separation head (11) and said evaporator (4), respectively.

12. Air conditioning system according to claim 1, characterized in that the condenser (2) comprises a liquid collecting pipe (13) and a gas distributing pipe (14), the gas distributing pipe (14) being connected to a gas outlet of the compressor (1), the liquid collecting pipe (13) being connected to the throttling means (3).

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