JP2001227895A - Method for cleaning piping of air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for cleaning an air conditioner capable of obtaining a long-term reliability even by utilizing existing piping for the conditioner using an HFC refrigerant by realizing cleaning of the piping in a short time. SOLUTION: The method for cleaning the air conditioner comprises the steps of conveying an article from one end of the piping of the conditioner via a compression gas and removing a foreign matter retained in the piping from another end of the piping. The method further comprises the steps of predicting a time for passing the article through the piping according to each of a length, a diameter of the piping and an atmospheric temperature, measuring the passing time, comparing the predicted time with the time for passing the article, and detecting stopping of the article in the piping.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction method for installing a new air conditioner while leaving the existing piping of the air conditioner.

[0002]

2. Description of the Related Art A refrigeration cycle used in a separate type air conditioner is configured by connecting a refrigerant flow control unit having an expansion mechanism such as a refrigeration compressor, a heat exchanger, a capillary tube or an expansion valve by a pipe such as a copper pipe. And a fluid filled in the refrigeration cycle, such as a refrigerant and a lubricating oil composition.

In a separate type air conditioner, a refrigerating compressor,
An outdoor unit having a heat exchanger is connected to an indoor unit having a heat exchanger installed at a location where refrigeration and air conditioning is performed by piping such as a copper pipe. In such a refrigeration cycle, a part or all of the refrigerant and the lubricating oil composition are filled in the outdoor unit in advance, the valve of the outdoor unit is closed, and the refrigerant is connected to the indoor unit using piping at the time of construction, and then the refrigerant is indoors. It is common to form a refrigeration cycle by circulating it through an external unit.

[0004] In recent years, from the viewpoint of global environmental protection, the refrigerant for air conditioners has been switched from HCFC to HFC. When replacing an air conditioner using HCFC with an air conditioner using HFC refrigerant, the piping is often also new. However, in the case where the pipe is embedded in the wall of the building in advance, it is preferable to use the conventionally used pipe without impairing the appearance of the building. Such existing pipes may be contaminated with oil, sludge, etc. from a conventionally installed air conditioner. When such an existing pipe is used to replace an air conditioner using an HCFC-based refrigerant with an air conditioner using an HFC-based refrigerant, the following problem occurs. In an air conditioner using an HFC-based refrigerant, ester oil or ether oil is used as a refrigerating machine oil. These oils are traditional
Compared to mineral oil, which is often used as a refrigerating machine oil for air conditioners using HCFC-based refrigerants, it has higher hygroscopicity and is more likely to be degraded by moisture. The air conditioner stopped. for that reason
Air conditioning systems using HFC refrigerants require stricter moisture management than ever before.

Conventionally, in order to remove such dirt, it has been necessary to remove sludge by circulating a solvent such as chlorofluorocarbon in the piping by a piping cleaning device having a pump.

[0006]

However, these pipe cleaning apparatuses are large in size and require a long cleaning time, so that there is a problem that the cost is increased and the construction time is increased.

Accordingly, the present invention provides a method for cleaning an air conditioner which realizes cleaning of an existing pipe in a short time and which can obtain long-term reliability even for an air conditioner using an HFC-based refrigerant even when the existing pipe is used. The purpose is to provide.

[0008]

Means for Solving the Problems In order to solve the above problems, the invention according to claim 1 of the present invention is to convey articles by compressed gas from one end of a pipe of an air conditioner. In a pipe cleaning method for an air conditioner for removing foreign matter remaining in a pipe from the other end of the pipe, a time required for an article to pass through the pipe is measured.

The invention described in claim 2 is the first invention.
The pipe cleaning method for an air conditioner described above is characterized in that the article predicts the time that the article will pass through the pipe for each length, diameter, and outside temperature of the pipe, and measures the time that the article passes.

[0010] The invention according to claim 3 is characterized in that a sound of an article passing through a pipe is heard or vibration is measured.

The invention according to claim 4 is characterized in that, when it is detected that the article has stopped in the pipe, the pressure of the compressed gas is increased.

Further, the invention according to claim 5 is characterized in that, when it is detected that the article has stopped in the pipe, the compressed gas is caused to flow from the pipe port opposite to the pipe port in which the article has been inserted.

The invention according to claim 6 is characterized in that, when it is detected that the article has stopped in the pipe, a wire or the like is passed through the pipe.

The invention according to claim 7 is characterized in that, when it is detected that the article has stopped in the pipe, a wire or the like is passed through the pipe from the pipe port opposite to the pipe port into which the article has been inserted. I do.

Further, the invention according to claim 8 is characterized in that a string is attached to the article.

The invention according to claim 9 is characterized in that, when it is detected that the article has stopped in the pipe, the string is pulled and the inserted article is pulled out.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The first and second embodiments of the present invention are intended to predict the time for an article to pass through a pipe for each length and outside temperature of a pipe, and to measure the time to pass. . This makes it possible to determine that the article has stopped in the pipe by comparing the predicted time with the time when the article passes.

In a third embodiment of the present invention, in a pipe connecting an indoor unit and an outdoor unit of an air conditioner, a sound of an article passing through the pipe or a vibration is measured. Thereby, the movement of the article can be detected.

A fourth embodiment of the present invention is directed to a piping for connecting an indoor unit and an outdoor unit of an air conditioner, wherein the article is
When it is detected that the article has stopped in the pipe, the pressure of the compressed gas pushing the article is increased. Thereby, the article can be extruded.

According to a fifth embodiment of the present invention, in a pipe for connecting an indoor unit and an outdoor unit of an air conditioner,
When it is detected that the article has stopped in the pipe, the compressed gas flows from the pipe port opposite to the pipe port into which the article is inserted.
Thereby, an article can be extruded from the piping opening in which the article was inserted.

In a sixth embodiment of the present invention, in a pipe connecting an indoor unit and an outdoor unit of an air conditioner, a wire or the like is passed through the pipe. Thereby, even if an article stops in piping, an article can be pushed out with a wire.

In a seventh embodiment of the present invention, in a pipe connecting an indoor unit and an outdoor unit of an air conditioner, a wire or the like is passed through a pipe port opposite to a pipe port into which articles are inserted. Accordingly, even when the article stops in the pipe, the article can be pushed out from the pipe port into which the article has been inserted.

In the eighth and ninth embodiments of the present invention, a string is attached to an article to be inserted into a pipe connecting an indoor unit and an outdoor unit of an air conditioner. Thereby, the movement of the article can be detected. Further, when the article stops in the pipe, the string attached to the article can be pulled to pull out the article.

[0024]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a model diagram showing an example of an installation state of an air conditioner to which the pipe cleaning method of the present invention is applied. The air conditioner is, for example, three indoor units 2, 3, 4 with respect to the outdoor unit 1.
Are provided via the branching unit 5. The piping 6 is routed in a state of being embedded in the wall of the house in consideration of the appearance of the house. In the case of an indoor unit separated from the outdoor unit, the length of the piping may be as long as 30 m. The pipe cleaning method of the present invention is performed only on the pipe 6 before connecting the outdoor unit 1 and the indoor unit 2.

This cleaning method will be described with reference to FIG. First, the article 7 is inserted into the pipe 6 from one end 10 of the pipe 6. After the article 7 has been inserted, a pressure gauge 9 and a compressed gas cylinder 8 are connected to the insertion port side, and the article 7 is blown out by blowing a compressed gas. The article 7 reaches the other end 11 of the pipe 6 and is discharged together with oil, moisture and the like in the pipe.

At this time, the temperature change of the pipe 6 causes
Oil staying inside changes its viscosity. FIG. 3 shows a change in viscosity of a typical oil with respect to temperature. FIG.
30m long pipe 6 (and oil) temperature and article 7
Indicates the time for which passes through the pipe 6. Therefore, piping 6
As the temperature of the oil decreases, the viscosity of the oil increases, the resistance increases, and the time for the article 7 to pass through the pipe increases.
Conversely, when the temperature of the pipe 6 increases, the viscosity of the oil decreases and the resistance decreases, so that the time required to pass through the pipe decreases. Further, since the passing time varies depending on the pipe length, the passing time is estimated by multiplying the time for the standard pipe length by the ratio of the standard pipe length to the actual pipe length.
Thus, the time for the article 7 to pass through the pipe 6 is
It can be predicted from the length of the pipe 6 and the temperature of the pipe 6. Therefore, if the indication of the pressure gauge 9 does not decrease after the elapse of the predicted time after the article 7 starts to move, it is considered that the article 7 has stopped in the pipe 6 due to bending inside the pipe 6 or the like.
Gradually increase the pressure of the compressed gas. Then, the article 7 starts to move again. When the article 7 passes through the pipe 6,
Since the other end 11 of the pipe 6 is opened, the pressure in the pipe 6 decreases, and the indication of the pressure gauge 9 also decreases. Therefore, piping 6
Can be determined, and the end of the work can be confirmed.

However, if the pipe 6 is largely flat, the article 7 may not pass through the pipe 6 even if the pressure of the compressed gas is increased. In that case, the other end 1 of the pipe 6
A compressed gas cylinder 8 is connected to 1, and compressed gas is blown to blow out the article 7 to remove the article 7 from the pipe 6. By such a method, even when the article 7 is clogged in the pipe 6, the article 7 can be removed.

Next, another embodiment will be described with reference to FIG. First, the article 7 is inserted into the pipe 6 from one end 10 of the pipe 6. After the article 7 is inserted, the pipe 13 with the stethoscope 12 and the compressed gas cylinder 8 are connected to the insertion port side, and the article 7 is blown out by blowing compressed gas. The article 7 is the other end 11 of the pipe 6
And is discharged together with the oil and water in the pipe.

When the article 7 is pressure-fed with compressed gas, the pressure is gradually increased. However, when the article 7 inserted into the pipe 6 starts to move, a sound of the compressed gas flowing and a sound of the article 7 moving are generated. By listening to this sound 12, it can be confirmed that the article 7 inserted into the pipe 6 starts to move. Furthermore, when the article 7 stops in the pipe 6 due to bending inside the pipe 6, the sound stops, and it can be confirmed that the article 7 has stopped. In this case, when the pressure of the compressed gas is gradually increased, the article 7 starts to move and a sound is generated. When the article 7 passes through the pipe 6, the other end 11 of the pipe 6 is opened.
The flow velocity of the compressed gas flowing through the inside changes, the frequency of the generated sound changes, and it can be determined that the sound has passed through the pipe 6, and the end of the work can be confirmed.

Next, another embodiment will be described with reference to FIGS. When the article 7 stops in the pipe 6 due to bending inside the pipe 6 or the like, the pipe 6
The article 14 is pushed through the wire 14 and pushed out from the pipe 6. Further, even if the wire 14 is inserted from the other end 11 of the pipe 6 and the article 7 is pushed, the article 7 can be removed from the pipe 6.

Next, another embodiment will be described with reference to FIG. First, the article 7 with the string 15 is inserted into the pipe 6 from one end 10 of the pipe 6. After the article 7 is inserted, the transparent pipe 16 and the compressed gas cylinder 8 are connected to one end 10 of the pipe 6, and the article 7 is pressure-fed by blowing compressed gas. The article 7 reaches the other end 11 of the pipe 6 and is discharged together with oil, moisture and the like in the pipe.

When the article 7 is pressure-fed with compressed gas, the pressure is gradually increased. When the article 7 inserted into the pipe 6 starts to move, it is confirmed that the cord 15 starts to move and the article 7 inserted into the pipe 6 starts to move. it can. Furthermore, when the article 7 passes through the pipe 6, the string 15 extends, but when the article 7 stops in the pipe 6 due to bending inside the pipe 6, the extension of the string 15 stops. Therefore, it can be confirmed that the article 7 has stopped. In this case, when the pressure of the compressed gas is gradually increased, the article 7 starts to move again, and the string 15 starts to expand. When the article 7 passes through the pipe 6, the extension of the string 15 stops. Therefore, it can be determined that the vehicle has passed through the pipe 6, and the end of the operation can be confirmed.

However, when the pipe 6 is largely flat, the article 7 may not pass through the pipe 6 even if the pressure of the compressed gas is increased. In that case, the string 15 attached to the article 7 is pulled from one end 10 of the pipe 6, and the article 7 is removed from the pipe 6. By such a method, even when the article 7 is clogged in the pipe 6, the article 7 can be removed.

[0035]

As is apparent from the above embodiment, according to the first and second aspects of the present invention, the length, diameter,
It is possible to predict the time that the article passes through the pipe for each outside temperature, measure the time that the article passes, and compare the predicted time with the time that the article passes to detect that the article has stopped in the pipe.

According to the third aspect of the invention, the movement of the article can be detected by listening to the sound of the article passing through the pipe or measuring the vibration.

According to the fourth aspect of the present invention, when it is detected that the article has stopped in the pipe, the pressure of the compressed gas for pushing the article can be increased to push the article.

According to the fifth aspect of the present invention, when it is detected that the article has stopped in the pipe, the compressed gas flows from the pipe port opposite to the pipe port into which the article is inserted, and the article is inserted into the pipe port. From the product.

According to the sixth and seventh aspects of the present invention, when it is detected that the article has stopped in the pipe, the article can be pushed through the pipe by passing a wire or the like through the pipe.

According to the eighth and ninth aspects of the present invention,
A string is attached to an article to be inserted into the pipe, and the movement of the article can be detected. Further, when it is detected that the article has stopped in the pipe, the string attached to the article can be pulled and the article can be pulled out.

[Brief description of the drawings]

FIG. 1 is a model diagram showing an example of an installation state of an air conditioner to which a pipe cleaning method of the present invention is applied.

FIG. 2 is a schematic view of a pipe cleaning method according to an embodiment of the present invention.

FIG. 3 is a diagram showing a change in viscosity of a typical oil with respect to temperature.

FIG. 4 is a diagram showing the temperature of a pipe (and oil) having a length of 30 m and the time required for an article to pass through the pipe.

FIG. 5 is a schematic view of another embodiment of the pipe cleaning method of the present invention.

FIG. 6 is a schematic view of another embodiment of the pipe cleaning method of the present invention.

FIG. 7 is a schematic diagram of another embodiment of the pipe cleaning method of the present invention.

FIG. 8 is a schematic view according to another embodiment of the pipe cleaning method of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 outdoor unit 2 indoor unit 3 indoor unit 4 indoor unit 5 branch unit 6 pipe 7 article 8 compressed gas cylinder 9 pressure gauge 10 one end of pipe 6 11 other end of pipe 6 12 stethoscope 13 pipe 14 wire 15 string 16 transparent pipe

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Yuichi Yakumaru 1006 Kadoma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Inventor Hironao Numamoto 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) The inventor Shigehiro Sato 1006 Odaka Kadoma, Kadoma City, Osaka Pref. Eiji Kado 1006 Kadoma, Kazuma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Yasuaki Matsumoto 1006 Kazuma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. 1006 Matsushita Electric Industrial Co., Ltd. F term (reference) 3B116 AA13 AB51 BA08 BA24 BA37 CD42 CD43

Claims (9)

[Claims] 1. A conveyed article with compressed gas from one end of a pipe through which a working medium flows between an indoor unit and an outdoor unit of an air conditioner, thereby removing foreign matter remaining inside the pipe from the other end of the pipe. In the method of cleaning piping of air conditioners,
A method of cleaning a pipe of an air conditioner, comprising measuring a time required for the article to pass through the pipe from one end to another, and detecting that the article has stopped in the pipe. 2. Predicting a time required for the article to pass from end to end of the pipe for each length, diameter, and outside air temperature of the pipe, measuring a time required for the article to pass, and comparing the estimated time with the estimated time. The method for cleaning a pipe of an air conditioner according to claim 1, wherein it is detected that the pipe has stopped in the pipe. 3. A conveyed article with compressed gas from one end of a pipe for circulating a working medium between an indoor unit and an outdoor unit of an air conditioner, thereby removing foreign matter remaining inside the pipe from the other end of the pipe. In the method of cleaning piping of air conditioners,
A method of cleaning an existing pipe of an air conditioner, wherein the movement of the article is detected by listening to the sound of the article passing through the pipe or measuring the vibration. 4. A foreign matter remaining in the piping is removed from the other end of the piping by conveying the article with compressed gas from one end of the piping for circulating the working medium between the indoor unit and the outdoor unit of the air conditioner. In the method of cleaning piping of air conditioners,
A method for cleaning a pipe of an air conditioner, comprising increasing the pressure of the compressed gas when detecting that the article has stopped in the pipe. 5. A foreign matter remaining in the piping is removed from the other end of the piping by conveying the article with compressed gas from one end of the piping for flowing the working medium between the indoor unit and the outdoor unit of the air conditioner. In the method of cleaning piping of air conditioners,
A method for cleaning a pipe of an air conditioner, characterized in that when detecting that the article has stopped in a pipe, a compressed gas is caused to flow from a pipe port opposite to a pipe port into which the article has been inserted to extrude the article. 6. A conveyed article with compressed gas from one end of a pipe through which a working medium flows between an indoor unit and an outdoor unit of an air conditioner, thereby removing foreign matter remaining in the pipe from the other end of the pipe. In the method of cleaning piping of air conditioners,
A method of cleaning a pipe of an air conditioner, comprising, when detecting that the article has stopped in a pipe, passing a wire or the like through the pipe and extruding the article with the wire. 7. The pipe cleaning method for an air conditioner according to claim 6, wherein a wire or the like is passed through the pipe from the pipe port opposite to the pipe port into which the article is inserted, and the article is extruded with the wire. 8. A conveyed article with compressed gas from one end of a pipe through which a working medium flows between an indoor unit and an outdoor unit of an air conditioner, thereby removing foreign matter remaining inside the pipe from the other end of the pipe. In the method of cleaning piping of air conditioners,
A method of cleaning a pipe of an air conditioner, comprising: attaching a string to the article; and detecting a movement of the article based on a movement of the string. 9. The pipe cleaning method for an air conditioner according to claim 8, wherein when it is detected that the article has stopped in the pipe, the string is pulled to pull out the article.