Bypassing flushing method for vehicle air conditioner

Abstract

The present invention relates to a vehicle air conditioner flushing method using a flushing device that repeatedly performs a cycle of recovering refrigerant and oil flowing in from a low-pressure connection of a vehicle air conditioner system to a high-pressure connection of the vehicle air conditioner system through a low-pressure connection hose, a waste oil separator, a filter, a compressor, an oil separator, said waste oil separator, a recovery container, and a high-pressure connection hose, wherein the flushing device is equipped with an inlet control valve, an outlet control valve, and a bypass valve in the recovery container, and while the inlet control valve and the outlet control valve are closed and the bypass valve is open, the method comprises: a refrigerant flushing step that repeatedly performs a cycle of recovering refrigerant and oil flowing in from a low-pressure connection of the vehicle air conditioner system to a high-pressure connection of the vehicle air conditioner system through the low-pressure connection hose, said waste oil separator, the filter, said compressor, said oil separator, said waste oil separator, the bypass valve, and the high-pressure connection hose; The method is characterized by including a refrigerant recovery step in which, with the bypass valve closed and the inlet control valve open, flushed refrigerant flowing in from the low-pressure connection of the vehicle air conditioning system is recovered through the inlet control valve to the recovery container. According to this, problems such as environmental pollution, weakened device durability, increased costs, and reduced flushing effect caused by conventional flushing operations can be resolved.

Description

Technology Field

[0001] The present invention relates to a flushing method for a vehicle air conditioner, and more specifically, to a bypass flushing method for a vehicle air conditioner using a bypass valve. Background Technology

[0002] The process of replacing the refrigerant and oil circulating in a vehicle's air conditioning system is called flushing, and it is a type of air conditioning service that is currently commonly performed at car repair shops and auto repair shops.

[0003] Specifically, the vehicle air conditioning system is equipped with a compressor for circulating refrigerant, and 100 to 150 cc of refrigerant oil is injected to ensure smooth operation of the compressor.

[0004] As leaks occur in the vehicle's air conditioning system or foreign substances are generated due to cylinder friction inside the compressor, the refrigerant oil within the system also loses its properties due to moisture and foreign substances as the vehicle ages.

[0005] Such contaminated refrigerant oil causes performance degradation and compressor failure in vehicle air conditioners, so a vehicle maintenance service, namely a vehicle air conditioner flushing service, is being performed to discharge contaminated refrigerant from aging vehicle air conditioner systems and inject new, clean refrigerant and oil.

[0006] Referring to FIG. 1, a conventional vehicle air conditioner flushing method has a method (forward flushing) to increase the purity of the refrigerant by repeating a cycle in which the waste oil is separated and the clean refrigerant is recovered into the vehicle air conditioner system through a flow in which the refrigerant and oil flowing in from the low-pressure connection of the vehicle air conditioner system pass through the low-pressure connection hose (11) -> waste oil separator (12) -> filter (13) -> compressor (14) -> oil separator (15) -> waste oil separator (12) -> recovery container (16) -> high-pressure connection hose (17) and then flow back into the high-pressure connection of the vehicle air conditioner system.

[0007] Alternatively, a method (reverse flushing) was adopted to increase the purity of the refrigerant by repeating a cycle in which the waste oil is separated and the clean refrigerant is recovered into the vehicle air conditioning system through a flow in the opposite direction to the above, in which the refrigerant and oil flowing in from the high-pressure connection of the vehicle air conditioning system pass through the high-pressure connection hose (17) -> waste oil separator (12) -> filter (13) -> compressor (14) -> oil separator (15) -> waste oil separator (12) -> recovery container (16) -> low-pressure connection hose (11) and flow back into the low-pressure connection of the vehicle air conditioning system.

[0008] However, as described above, whether it is forward flushing or reverse flushing, the refrigerant pressure inside the recovery container (16) tends to rise excessively as it passes through the recovery container (16), and in such cases, the following problems occur.

[0009] (1) Environmental pollution

[0010] During the refrigerant recovery operation after the completion of flushing, the non-condensable refrigerant inside was exhausted to the outside due to the increase in internal pressure of the recovery container (16). As described above, the flushing device (10) having a general flushing refrigerant flow discharged about 1 to 2 kg of refrigerant into the atmosphere, causing environmental pollution.

[0011] (2) Weakening of the device's durability

[0012] During the flushing operation, the increase in internal pressure of the recovery container (16) caused the compressor (14) inside the flushing device (10) to operate excessively, which shortened its lifespan.

[0013] (3) Reduced flushing effect

[0014] In each cycle, the refrigerant inside the recovery container (16) is newly added to the flow of the refrigerant being flushed, thereby reducing the oil density in the circulating refrigerant, which leads to a reduction in the amount of pure waste oil discharged after the flushing operation is completed.

[0015] (4) Increase in costs

[0016] After the flushing is completed, the amount of refrigerant lost as described above must be replenished with new refrigerant, which results in additional costs. The problem to be solved

[0017] Accordingly, the objective of the present invention is to provide a vehicle air conditioner flushing method using an improved flushing refrigerant flow method, so-called 'bypassing flushing,' to solve problems such as environmental pollution, weakened durability of the device, increased costs, and reduced flushing effect caused by the refrigerant flow method of the conventional general vehicle air conditioner flushing method. means of solving the problem

[0018] To achieve the above objective, the present invention relates to a vehicle air conditioner flushing method using a flushing device that repeatedly performs a cycle of recovering refrigerant and oil flowing in from a low-pressure or high-pressure connection of a vehicle air conditioner system through a low-pressure or high-pressure connection hose, a waste oil separator, a filter, a compressor, an oil separator, said waste oil separator, a recovery container, and a high-pressure or low-pressure connection hose to the high-pressure or low-pressure connection of the vehicle air conditioner system, wherein the flushing device further comprises an inlet control valve installed in the refrigerant inlet line of the recovery container, an outlet control valve installed in the refrigerant outlet line of the recovery container, and a bypass valve that causes the refrigerant to bypass from the refrigerant inlet line to the refrigerant outlet line without passing through the recovery container, so as to the vehicle air conditioner flushing method, with the inlet control valve and the outlet control valve closed and the bypass valve open, the refrigerant and oil flowing in from the low-pressure or high-pressure connection of the vehicle air conditioner system through the low-pressure or high-pressure connection hose, said waste oil separator, said filter, said compressor, said A vehicle air conditioner flushing method is provided, characterized by comprising: a refrigerant flushing step of repeatedly performing a cycle of recovering the refrigerant to a high-pressure or low-pressure connection part of the vehicle air conditioner system through an oil separator, the waste oil separator, the bypass valve, and the high-pressure or low-pressure connection hose; and a refrigerant recovery step of recovering the flushed refrigerant flowing in from the low-pressure or high-pressure connection part of the vehicle air conditioner system to a recovery container through the low-pressure or high-pressure connection hose, the waste oil separator, the filter, the compressor, the oil separator, the waste oil separator, and the inlet control valve while the bypass valve is closed and the inlet control valve is opened.

[0019] Here, the vehicle air conditioner flushing method may further include a vacuuming step prior to the refrigerant flushing step, wherein the low-pressure connecting hose and the high-pressure connecting hose connected to the low-pressure connecting part and the high-pressure connecting part of the vehicle air conditioner system are blocked, and the inlet control valve, the outlet control valve, and the bypass valve are all opened, and a vacuum is created using a vacuum pump for all paths leading to the low-pressure or high-pressure connecting hose, the waste oil separator, the filter, the compressor, the oil separator, the waste oil separator, the recovery container, and the high-pressure or low-pressure connecting hose.

[0020] And, the vehicle air conditioner flushing method may further include a refrigerant injection step, which, following the vacuuming step and prior to the refrigerant flushing step, opens both the low-pressure connecting hose and the high-pressure connecting hose connected to the low-pressure and high-pressure connecting parts of the vehicle air conditioner system, and fills all the paths leading to the low-pressure or high-pressure connecting hose, the waste oil separator, the filter, the compressor, the oil separator, the waste oil separator, the recovery container, and the high-pressure or low-pressure connecting hose with refrigerant and oil flowing in from the low-pressure or high-pressure connecting part of the vehicle air conditioner system. Effects of the invention

[0021] As described above, the vehicle air conditioner flushing method according to the present invention has the following effects.

[0022] (1) Prevention of environmental pollution

[0023] Since there is no increase in internal pressure of the recovery container during the flushing operation, non-condensable refrigerant is not discharged into the atmosphere when the refrigerant is recovered to the vehicle air conditioning system to end the flushing. According to experiments, the amount of non-condensable refrigerant exhausted into the atmosphere is 200 to 300 g, which is significantly reduced compared to conventional methods.

[0024] (2) Increased device durability

[0025] Since the internal pressure of the recovery container does not increase, the compressor operates at a normal level, which has the effect of increasing the durability of the flushing device.

[0026] (3) Cost reduction

[0027] Since no refrigerant is emitted into the atmosphere, it offers cost savings on replenishing new refrigerant.

[0028] (4) Increased flushing effect

[0029] During bypass flushing operation, the initially injected refrigerant continues to circulate in the forward or reverse direction without the inflow of new refrigerant from the recovery container, thereby increasing the oil density of the flushing refrigerant. This increase in oil density leads to an increase in the amount of pure waste oil discharged at the end of the operation, thus enhancing the effect of flushing. Brief explanation of the drawing

[0030] FIG. 1 is a system configuration diagram for explaining a vehicle air conditioner flushing method according to the prior art, FIG. 2 is a configuration diagram of a flushing device used in a vehicle air conditioner flushing method according to an embodiment of the present invention. FIG. 3 is a system configuration diagram for explaining a vehicle air conditioner flushing method according to an embodiment of the present invention. Specific details for implementing the invention

[0031] A vehicle air conditioner flushing method according to an embodiment of the present invention uses a flushing device (20) as shown in FIG. 2. Most of the components forming the flushing device (20) are identical to a flushing device according to the prior art (see 10 in FIG. 1).

[0032] That is, the flushing device (20) is equipped with all the same components, such as a waste oil separator (22), filter (23), compressor (24), oil separator (25), and recovery container (26), from a low-pressure connecting hose (21) connected to a low-pressure connection part of a vehicle air conditioning system and a high-pressure connecting hose (27) connected to a high-pressure connection part.

[0033] However, in addition to the above configurations, the flushing device (20) further includes an inlet control valve (28) installed in the refrigerant inlet line (26a) of the recovery container (26), an outlet control valve (29) installed in the refrigerant outlet line (26b) of the recovery container (26), and a bypass valve (30) that causes the refrigerant to bypass from the refrigerant inlet line (26a) to the refrigerant outlet line (26b) without passing through the recovery container (26).

[0034] A vehicle air conditioner flushing method using such a flushing device (20) is performed in the order of i) vacuuming step, ii) refrigerant injection step, iii) refrigerant flushing step, and iv) refrigerant recovery step.

[0035] Referring to FIG. 3, in the vacuuming step, the valves of the low-pressure connecting hose (21) and the high-pressure connecting hose (27), which are connected to the low-pressure and high-pressure connecting parts of the vehicle air conditioning system, are first closed to block the inflow of refrigerant. Then, the inflow control valve (28), the outflow control valve (29), and the bypass valve (29) are all opened (i.e., opened). In this state, a vacuum pump (not shown in the drawing) provided in the flushing device (20) is driven to vacuum all the flow paths leading to the low-pressure connecting hose (21), the waste oil separator (22), the filter (23), the compressor (24), the oil separator (25), the waste oil separator (22), the recovery container (26), and the high-pressure connecting hose (27).

[0036] In the following refrigerant injection step, the low-pressure connecting hose (21) and the high-pressure connecting hose (27), which are connected to the low-pressure and high-pressure connecting parts of the vehicle air conditioning system, are both opened to fill all the paths leading from the low-pressure connecting hose (21), waste oil separator (22), filter (23), compressor (24), oil separator (25), waste oil separator (22), recovery container (26), and high-pressure connecting hose (27) with refrigerant and oil flowing in from the low-pressure connecting part (21) of the vehicle air conditioning system.

[0037] Next, in the refrigerant flushing step, the inlet control valve (28) and the outlet control valve (29) are first closed, and the bypass valve (30) is opened (i.e., opened). In this state, a cycle is repeated to recover the refrigerant and oil flowing in from the low-pressure connection of the vehicle air conditioning system to the high-pressure connection of the vehicle air conditioning system through the low-pressure connection hose (21), waste oil separator (22), filter (23), compressor (24), oil separator (25), the waste oil separator (22), the bypass valve (30), and the high-pressure connection hose (27). At this time, the refrigerant recovered to the high-pressure connection of the vehicle air conditioning system comes out again to the low-pressure connection, so the cycle can continue.

[0038] In the final refrigerant recovery step performed after the above cycle is repeated several times, with the bypass valve (30) closed and the inlet control valve (28) open, the flushed refrigerant flowing in from the low-pressure connection of the vehicle air conditioning system is recovered into the recovery container (26) via the low-pressure connection hose (21), waste oil separator (22), filter (23), compressor (24), oil separator (25), waste oil separator (22), and inlet control valve (28).

[0039] Meanwhile, the vehicle air conditioner flushing method described above is merely an example to aid in understanding the present invention, and therefore, the scope of rights or technical scope of the present invention as defined by the claims set forth below should not be limited as described above. Explanation of the symbols

[0040] 20: Flushing device 21: Low-pressure connecting hose 22: Waste oil separator 23: Filter 24: Compressor 25: Oil separator 26: Recovery container 26a: Refrigerant inlet line 26b: Refrigerant withdrawal line 27: High-pressure connecting hose 28: Inlet control valve 29: Outlet control valve 30: Bypass valve

Claims

Claim 1 A vehicle air conditioner flushing method using a flushing device that repeatedly performs a cycle of recovering refrigerant and oil flowing in from a low-pressure or high-pressure connection of a vehicle air conditioner system through a low-pressure or high-pressure connection hose, a waste oil separator, a filter, a compressor, an oil separator, said waste oil separator, a recovery container, and a high-pressure or low-pressure connection hose to the high-pressure or low-pressure connection of the vehicle air conditioner system, wherein the flushing device further comprises an inlet control valve installed in the refrigerant inlet line of the recovery container, an outlet control valve installed in the refrigerant outlet line of the recovery container, and a bypass valve that causes the refrigerant to bypass from the refrigerant inlet line to the refrigerant outlet line without passing through the recovery container, so as to, the vehicle air conditioner flushing method blocks the low-pressure connection hose and the high-pressure connection hose connected to the low-pressure connection and the high-pressure connection of the vehicle air conditioner system, and with the inlet control valve, the outlet control valve, and the bypass valve all open, the low-pressure or high-pressure connection hose, the waste oil separator, the filter, the compressor, the A vacuuming step in which a vacuum is created using a vacuum pump for all paths leading to the oil separator, the waste oil separator, the recovery container, and the high-pressure or low-pressure connecting hose; and a refrigerant injection step in which all paths leading to the low-pressure or high-pressure connecting hose, the waste oil separator, the filter, the compressor, the oil separator, the waste oil separator, the recovery container, and the high-pressure or low-pressure connecting hose are opened, and the low-pressure connecting hose and the high-pressure connecting hose, which are connected to the low-pressure or high-pressure connecting hose of the vehicle air conditioning system, are filled with refrigerant and oil flowing in from the low-pressure or high-pressure connecting hose of the vehicle air conditioning system.A vehicle air conditioner flushing method characterized by comprising: a refrigerant flushing step of repeatedly performing a cycle to recover refrigerant and oil flowing in from a low-pressure or high-pressure connection of a vehicle air conditioner system through a low-pressure or high-pressure connection hose, a waste oil separator, a filter, a compressor, an oil separator, a waste oil separator, a bypass valve, and a high-pressure or low-pressure connection hose to a high-pressure or low-pressure connection of the vehicle air conditioner system while the inlet control valve and the outlet control valve are closed and the bypass valve is open; and a refrigerant recovery step of recovering flushed refrigerant flowing in from a low-pressure or high-pressure connection of a vehicle air conditioner system to a recovery container through a low-pressure or high-pressure connection hose, a waste oil separator, a filter, a compressor, an oil separator, a waste oil separator, and the inlet control valve while the bypass valve is closed and the inlet control valve is open. Claim 2 delete Claim 3 delete

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