An air-conditioning refrigeration system pressure-charging device for refrigerating oil

Abstract

The present invention discloses a pressurized refrigerant oil filling device for an air-conditioning refrigeration system, which comprises an oil filling cylinder block (11). Axial ends of the oil filling cylinder block are respectively connected with an oil cylinder low-pressure side connecting pipe (14) and an oil cylinder high-pressure side connecting pipe (20). Stop valves are respectively and communicatively connected to the oil cylinder low-pressure side connecting pipe (14) and the oil cylinder high-pressure side connecting pipe (20). An oil cylinder slider (16) is coaxially and slidably installed in the oil filling cylinder block (11). The oil filling cylinder block (11) is divided into two parts of space by the oil cylinder slider (16). A thimble exhaust valve (18) is installed on the side of the oil filling cylinder block (11). The present invention can solve the problem that the refrigerant in the pipeline of the refrigeration system of existing air-conditioning equipment needs to be emptied before adding refrigerant oil.

Description

Technical Field

[0001] The present invention relates to the field of air-conditioning refrigerant oil filling devices, and more particularly to a pressurized refrigerant oil filling device for an air-conditioning refrigeration system. Background Art

[0002] As Figure 1 shown, an air-conditioning refrigeration system generally mainly consists of a compressor 1, a condenser 4, an expansion valve 6, an evaporator 8, a condensing fan 5 and an evaporating fan 7. When the air-conditioning operates for refrigeration, the compressor 1 compresses the low-temperature and low-pressure Freon gas into a high-temperature and high-pressure gas. The gas is sent into the condenser 4 through the high-pressure connecting pipe 3 and releases heat in the condenser 4, condensing into a high-pressure Freon liquid. After throttling and pressure reduction by the expansion valve 6, it enters the evaporator 8 to evaporate and absorb heat to cool the indoor air passing through the evaporator 8 under the action of the evaporating fan 7. The Freon liquid evaporates and absorbs heat and then becomes a low-pressure gas, which is sucked into the compressor again through the low-pressure connecting pipe 9. This cycle repeats to achieve the purpose of reducing the indoor temperature. A low-pressure needle valve 9 is installed in parallel on the low-pressure connecting pipe 10, and a high-pressure needle valve 2 is installed in parallel on the high-pressure connecting pipe 3. The medium in the pipeline can be discharged through the low-pressure needle valve 9 and the high-pressure needle valve 2.

[0003] When the air-conditioning compressor works, it mainly relies on the internal rotating components to compress the Freon gas. To ensure the reliable operation of the internal rotating components of the compressor 1, a certain amount of refrigerant oil must be added to the compressor 1 and the pipeline of the air-conditioning refrigeration system for lubrication to ensure the reliable operation of the air-conditioning compressor. When the air-conditioning is working, a part of the refrigerant oil in the air-conditioning refrigeration system exists in the compressor 1 and lubricates the internal moving components of the compressor 1. Another part of the refrigerant oil is dissolved in the Freon and circulates in the refrigeration system pipeline together with the Freon. When the pipeline of the air-conditioning equipment refrigeration system decreases due to certain reasons, the total amount of refrigerant oil inside the air-conditioning refrigeration system will decrease. When the amount of refrigerant oil decreases to a certain extent, the refrigerant oil that exists inside the compressor 1 and lubricates its moving components will also decrease accordingly. The compressor 1 will burn out and get stuck due to lack of oil and unreliable lubrication of its internal components.

[0004] To avoid the occurrence of such compressor failures, when it is detected that the amount of compressor refrigerant oil in the air-conditioning refrigeration system is too low, the current common practice is to completely discharge the refrigerant (Freon) in the air-conditioning refrigeration system pipeline, disconnect the pipeline joints at the inlet and outlet of the compressor 1, and replenish a certain amount of refrigerant oil through the oil replenishment port (or the steam return port) of the compressor 1. Then, reconnect the pipeline joints at the inlet and outlet of the compressor 1. After evacuating the internal pipeline of the entire air-conditioning equipment refrigeration system and filling it with Freon, the air-conditioning equipment can work normally again. This kind of operation is time-consuming and laborious. The large amount of Freon that needs to be discharged from the air-conditioning refrigeration system is not only uneconomical but also pollutes the environment. How to replenish refrigerant oil into the refrigeration system pipeline without completely discharging the Freon in the air-conditioning refrigeration system has become an urgent problem to be solved. Summary of the Invention

[0005] The object of the present invention is to provide a device for pressurized filling of refrigerant oil in an air-conditioning refrigeration system to solve the problem that the refrigerant oil in the refrigeration system of an air-conditioning equipment needs to be discharged from the internal pipeline of the system before refueling in the prior art.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A device for pressurized filling of refrigerant oil in an air-conditioning refrigeration system includes an oil filling cylinder body (11). One axial end of the oil filling cylinder body is connected with a low-pressure side connecting pipe of the oil cylinder (14), and the low-pressure side connecting pipe of the oil cylinder (14) is connected to the low-pressure inlet end of the compressor in the air-conditioning refrigeration system. The other axial end of the oil filling cylinder body is connected with a high-pressure side connecting pipe of the oil cylinder (20), and the high-pressure side connecting pipe of the oil cylinder (20) is connected to the high-pressure outlet end of the compressor in the air-conditioning refrigeration system. Stop valves are respectively connected and accessed in the low-pressure side connecting pipe of the oil cylinder (14) and the high-pressure side connecting pipe of the oil cylinder (20). An oil cylinder slider (16) is coaxially installed in the oil filling cylinder body (11). The oil cylinder slider (16) can slide axially along the oil filling cylinder body (11), and the oil filling cylinder body (11) is divided into two parts of space by the oil cylinder slider (16). A thimble exhaust valve (18) is installed on the side of the oil filling cylinder body (11), and when the thimble exhaust valve (18) is pressed, it communicates the inside and outside of the oil filling cylinder body (11).

[0008] Further, both axial ends of the oil filling cylinder body are respectively set as cylinder openings, and each cylinder opening is covered and installed with a cylinder head. The low-pressure side connecting pipe of the oil cylinder (14) and the high-pressure side connecting pipe of the oil cylinder (20) are respectively connected to the cylinder heads at corresponding positions.

[0009] Further, a one-way valve (17) is installed in the oil cylinder slider (16), and the two parts of the space separated in the oil filling cylinder body (11) are unidirectionally communicated by the one-way valve (17).

[0010] Further, the refueling cylinder block (11) is made of a transparent material.

[0011] The present invention can solve the problem that when adding refrigerant oil to the refrigeration system of existing air-conditioning equipment, it is necessary to evacuate the Freon inside the refrigeration system pipeline before refueling. Moreover, the design structure is simple and easy to implement, and it has the following advantages:

[0012] 1. When refueling the air-conditioning refrigeration system, there is no need to evacuate the refrigerant (Freon) in the system pipeline in advance, and it will not cause pollution to the environment.

[0013] 2. There is no need to provide an additional power source. Only by using the pressure difference between the high pressure in the high-pressure pipeline and the low pressure in the low-pressure pipeline of the air-conditioning refrigeration system, the compressor refrigerant oil can be supplemented and filled into the air-conditioning refrigeration system pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a schematic diagram of the refrigeration system of existing air-conditioning equipment.

[0015] Figure 2 is a structural diagram of the present invention.

[0016] Figure 3 is a working state diagram of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0017] The present invention will be further described below in conjunction with the drawings and embodiments.

[0018] As Figure 2 shown, a device for pressurized filling of refrigerant oil in an air-conditioning refrigeration system of the present invention includes a refueling cylinder block 11, a refueling cylinder head 12, an oil cylinder slider 16, an oil cylinder low-pressure side connecting pipe 14 and an oil cylinder high-pressure side connecting pipe 20, an oil cylinder low-pressure side connecting pipe stop valve 13, an oil cylinder high-pressure side connecting pipe stop valve 21, and a check valve 17.

[0019] Axial ends of the refueling cylinder block 11 (i.e., the upper and lower ends in the figure) are respectively set as cylinder openings. There are two refueling cylinder heads 12, and the two refueling cylinder heads 12 are tightly covered and installed at the two cylinder openings of the refueling cylinder block 11 by means of threaded sealing connection. The oil cylinder slider 16 is coaxially arranged inside the refueling cylinder block 11. The oil cylinder slider 16 can slide up and down along the axis of the refueling cylinder block 11, and the outer diameter of the oil cylinder slider 16 matches the inner diameter of the refueling cylinder block 11. The refueling cylinder block 11 is divided into upper and lower two-part spaces A and B by the oil cylinder slider 16.

[0020] The fuel injector cylinder block 11 is made of transparent material, through which the movement of the oil cylinder slider 16 in the cylinder block and the flow of Freon and refrigerant oil inside it can be observed. A high-pressure side connection nozzle 19 is provided at the center of the fuel injector cylinder head at the lower part of the fuel injection cylinder block 11, and one end of the oil cylinder high-pressure side connecting pipe 20 is connected to the high-pressure side connection nozzle 19. A low-pressure side connection nozzle 15 is provided at the center of the fuel injector cylinder head 12 at the upper part of the fuel injection cylinder block 11, and one end of the oil cylinder low-pressure side connecting pipe 14 is connected to the high-pressure side connection nozzle 19.

[0021] A thimble exhaust valve 18 is installed on the side of the fuel injector cylinder block 11. The position of the thimble exhaust valve 18 corresponds to space B. By using a tool to press against the valve needle at the center of the thimble exhaust valve 18, the gas in space B can be discharged from the fuel injector cylinder block 11.

[0022] As Figure 3 shown, the other end of the oil cylinder low-pressure side connecting pipe 14 is communicated with the low-pressure needle valve 9 of the air-conditioning refrigeration system, and an oil cylinder low-pressure side connecting pipe stop valve 13 is connected in series in the oil cylinder low-pressure side connecting pipe 14 to control the on-off of the pipeline. The other end of the oil cylinder high-pressure side connecting pipe 20 is communicated with the high-pressure needle valve 2 of the air-conditioning refrigeration system, and an oil cylinder high-pressure side connecting pipe stop valve 21 is connected in series in the oil cylinder high-pressure side connecting pipe 20 to control the on-off of the pipeline.

[0023] A check valve 17 is installed at the center of the oil cylinder slider 16. The check valve 17 unidirectionally connects space A and space B, and the connection direction is from space B to space A. When the pressure in space B is greater than that in space A, the gas inside B will flow into A, and the reverse flow is not allowed.

[0024] When it is necessary to supplement the refrigerant oil into the refrigeration system of the air-conditioning equipment, first power on and start the air-conditioning equipment for refrigeration work. At this time, the pressure of the Freon gas inside the pipeline at the high-pressure needle valve 2 on the high-pressure connecting pipe 3 of the refrigeration system of the air-conditioning equipment is about 1.5 MPa, and the pressure of the Freon gas inside the pipeline at the low-pressure needle valve 9 on the low-pressure connecting pipe 10 of the refrigeration system of the air-conditioning equipment is about 0.2 MPa. Unscrew the oil filler cylinder head 12 from the oil filler cylinder body 11, pour the refrigerant oil to be added into its internal space A, and screw the oil filler cylinder head 12 back onto the oil filler cylinder body 11 again (note that spaces A and B must not leak air). Connect one end of the low-pressure side connecting pipe 14 of the oil cylinder to the low-pressure side connecting pipe nozzle 15, and keep the cut-off valve 13 of the low-pressure side connecting pipe of the oil cylinder open; connect one end of the high-pressure side connecting pipe 20 of the oil cylinder to the high-pressure side connecting pipe nozzle 19, keep the cut-off valve 21 of the high-pressure side connecting pipe of the oil cylinder closed, and connect the other end to the high-pressure needle valve 2 of the air-conditioning refrigeration system; use a tool to hold the valve needle at the center of the thimble exhaust valve 18, and at the same time slowly open the cut-off valve 2 of the high-pressure side connecting pipe of the oil cylinder, so that the Freon gas in the high-pressure pipeline 3 of the refrigeration system flows through the high-pressure side connecting pipe 20 of the oil cylinder into the space B of the oil filler cylinder body 11, and expel the air in the space B from the thimble exhaust valve 18. When Freon gas is discharged from the thimble exhaust valve 18, it means that the space B is filled with Freon gas and the air in the space B is expelled. At this time, immediately release the tool holding the thimble exhaust valve 18, and at the same time quickly close the cut-off valve 21 of the high-pressure side connecting pipe of the oil cylinder; slowly open the cut-off valve 21 of the high-pressure side connecting pipe of the oil cylinder again, and use the high-pressure Freon gas (1.5 MPa) in the space B to push the oil cylinder slider 16 to move upward. The refrigerant oil in the space A gradually fills the space A and the low-pressure side connecting pipe 14 of the oil cylinder. When it is found that the refrigerant oil fills to the end of the low-pressure side connecting pipe 14 connected to the low-pressure needle valve 9, immediately close the cut-off valve 21 of the high-pressure side connecting pipe of the oil cylinder; connect the other end of the low-pressure side connecting pipe 14 to the low-pressure needle valve 9 of the air-conditioning refrigeration system. At this time, open the cut-off valve 21 of the high-pressure side connecting pipe of the oil cylinder again, and the refrigerant oil in the space A will be instantly pressed into the air-conditioning refrigeration system pipeline from the low-pressure needle valve 9; immediately close the cut-off valve 14 of the high-pressure side connecting pipe of the oil cylinder at this time. Because the space B is filled with high-pressure Freon gas and the space A is filled with low-pressure Freon gas, the high-pressure Freon gas in the space B will slowly flow into the space A. After about 5 minutes, the pressure between the two reaches an equilibrium of about 0.2 MPa.

[0025] At this time, the oil cylinder slider 16 has slid to the top of the oil filler cylinder body 11. Therefore, the actual volume of space A is zero, and the volume of space B reaches the maximum. At this time, the low-pressure side connecting pipe 14 of the oil cylinder and the space B in the oil filler cylinder body contain low-pressure (0.2 MPa) Freon gas. Immediately close the stop valve 13 of the low-pressure side connecting pipe of the oil cylinder, disconnect the low-pressure side connecting pipe 14 of the oil cylinder from the low-pressure needle valve 9. After shutting down the air-conditioning equipment and waiting for 5 minutes, the pressure on the high-pressure side of the air-conditioning refrigeration system will drop to about 0.5 MPa. Disconnect the high-pressure side connecting pipe 20 of the oil cylinder from the high-pressure needle valve 2, and the supplementary oil filling work of the air-conditioning refrigeration system is completed. What the air-conditioning refrigeration system loses is only the low-pressure (0.2 MPa) Freon gas contained in the low-pressure side connecting pipe 14 of the oil cylinder and the space B in the oil filler cylinder body. Since the amount of the low-pressure (0.2 MPa) Freon gas is extremely small, this method of supplementing the refrigerant oil is economical and effective.

[0026] The embodiments described in the present invention are only descriptions of the preferred embodiments of the present invention, and do not limit the concept and scope of the present invention. Without departing from the design idea of the present invention, various modifications and improvements made by those skilled in the art to the technical solutions of the present invention shall fall within the protection scope of the present invention. The technical content claimed by the present invention has been fully recorded in the claims.

Claims

1. A device for pressurized filling of refrigerant oil in an air-conditioning refrigeration system, characterized in that, it includes an oil filling cylinder body (11). One axial end of the oil filling cylinder body is connected with a low-pressure side connecting pipe of the oil cylinder (14), and the low-pressure side connecting pipe of the oil cylinder (14) is connected to the low-pressure inlet end of the compressor of the air-conditioning refrigeration system. The other axial end of the oil filling cylinder body is connected with a high-pressure side connecting pipe of the oil cylinder (20), and the high-pressure side connecting pipe of the oil cylinder (20) is connected to the high-pressure outlet end of the compressor of the air-conditioning refrigeration system. Stop valves are respectively and separately communicated and connected in the low-pressure side connecting pipe of the oil cylinder (14) and the high-pressure side connecting pipe of the oil cylinder (20). An oil cylinder slider (16) is coaxially installed in the oil filling cylinder body (11). The oil cylinder slider (16) can slide axially along the oil filling cylinder body (11), and the oil filling cylinder body (11) is divided into two parts of space by the oil cylinder slider (16). A thimble exhaust valve (18) is installed on the side of the oil filling cylinder body (11), and when the thimble exhaust valve (18) is pressed, it communicates the inside and outside of the oil filling cylinder body (11); both axial ends of the oil filling cylinder body are respectively set as cylinder openings, and each cylinder opening is respectively covered and installed with a cylinder head. The low-pressure side connecting pipe of the oil cylinder (14) and the high-pressure side connecting pipe of the oil cylinder (20) are respectively connected to the cylinder heads at corresponding positions; a check valve (17) is installed in the oil cylinder slider (16), and the two parts of the space divided in the oil filling cylinder body (11) are unidirectionally communicated by the check valve (17).

2. The device for pressurized filling of refrigerant oil in an air-conditioning refrigeration system according to claim 1, characterized in that, the oil filling cylinder body (11) is made of a transparent material.

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