JPH0371042A - Detector for degree of deterioration in refrigerant of refrigerator - Google Patents

Abstract

PURPOSE:To accurately detect deterioration of refrigerant without sampling and extracting refrigerant in a refrigerant circuit by arranging a metallic body in a refrigerant passage and observing change in color of the metallic body according to deterioration of refrigerant. CONSTITUTION:An observation window 4 for observing the inside is provided to the central part of the main body 3 of sight glass 1. A metallic piece 5a described hereunder is supported by a supporting member 6 in the inside thereof. This metallic piece 5a is oxidized by HCl produced by deterioration of refrigerant and discolored. Discoloration of the metallic piece 5a can be observed by the naked eye through the observation window 4. Further in order to automatically detect discoloration of the metallic piece 5a, e.g. such a method is utilized that the observation window 4 of the sight glass 1 is covered by a cover member 7 to interrupt light projected from the outside. The surface of the metallic piece 5a is irradiated with constant amount of light emitted from a LED 8 arranged to the inside and intensity of reflected light is detected by a phototransistor 9.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a refrigerant deterioration degree detection device for a refrigeration system that detects deterioration of refrigerant in a refrigeration circuit, and particularly relates to measures for improving deterioration degree detection performance. Regarding.

(Prior Art) Conventionally, as disclosed in JP-A No. 56-70082, for example, refrigerants such as R12 and R22 are decomposed due to the catalytic action of the metal paulownia material constituting the refrigerant circuit, especially when the temperature is still high. It is a well-known phenomenon that chlorine radicals are generated, and these chlorine radicals react with lubricated surfaces contained in the refrigerant to generate unsaturated hydrocarbons and HCρ.

This HCI+ may cause corrosion of the constituent materials in the refrigerant circuit, or the viscosity may decrease due to deterioration of the lubricating surface, which may impair the lubricating function.

Therefore, it is possible to accurately detect when the refrigerant deteriorates as described above.
Measures such as replacing the refrigerant must be taken, but generally speaking, to detect deterioration of the refrigerant, a sample of the refrigerant is extracted from the refrigerant circuit, and the refrigerant changes color due to deterioration, so the color of the refrigerant is visually observed. Methods such as determining the chloride ion concentration using chromatography have been adopted.

(Problem to be solved by the invention) However, in this case, in order to reliably detect deterioration of the refrigerant and effectively prevent the deterioration of the lubricating oil's function, it is necessary to sample the refrigerant from the refrigerant circuit many times. However, in this case, the amount of refrigerant decreases, so there is a risk that the operating characteristics will change. Further, as the refrigerant is extracted many times, there is a possibility that the amount of refrigerant may become insufficient and replenishment may be necessary.

The present invention focuses on the fact that HCβ, etc. (and Q ions) are multiplied by deterioration of the refrigerant, and metals are corroded by reactions with CD ions. By taking measures to directly detect the refrigerant in the refrigerant circuit, there is no need to sample the refrigerant in the refrigerant circuit.
The objective is to accurately detect deterioration of refrigerant.

(Means for Solving the Problems) In order to achieve the above-mentioned object 1-1, the decisive means of the present invention is, as shown in FIG. Metal body (5a) placed inside
and an observation window (4) provided in the refrigerant passage corresponding to the arrangement position of the metal body (5a) for observing a change in color of the metal body (5a) due to deterioration of the refrigerant. That is.

As shown in FIG. 5, the second solution is to use a metal body (5a) disposed in the refrigerant passage of the refrigeration equipment as a refrigerant deterioration degree detection device for the refrigeration equipment, and a metal body (5a) arranged in the refrigerant passage of the refrigeration equipment and Change detection means (11) for detecting a change in color of the metal body (5a)
This is the configuration that provides the following.

As shown in FIG. 9, the third solution is to use a metal body (5b or 6c) placed in the refrigerant passage of the refrigeration equipment as a refrigerant deterioration degree detection device for the refrigeration equipment and The present invention is further provided with a change detection means (11) for detecting a change in electrical resistance of the metal body (5b or 5c).

As shown in FIG. 1, in addition to the second or third solving means, the fourth solving means receives the output of the change detection means (11), and when the change value is equal to or greater than a predetermined value, the refrigerant Signal output means (51) for outputting a refrigerant deterioration signal to notify deterioration
The configuration is such that the

The fifth solution is the first solution mentioned above. Second. In the third or fourth solution, the metal body (5) is placed on the liquid pipe side of the condenser of the refrigeration system.

The sixth solution is the above-mentioned first solution. Second. In the third or fourth solution, the metal body (5) is placed in the liquid line on the high pressure side of the refrigeration system.

The seventh solution is the above-mentioned first solution. Second. In the third or fourth solution, the refrigeration apparatus is provided with an oil separator for separating oil in discharge gas discharged from the compressor and returning the oil to the compressor. The metal body (5) is arranged in a reflux path from the oil separator.

(Function) As explained above, in the invention of claim (1), the metal body (5a) disposed in the refrigerant passage of the refrigeration system decomposes into unsaturated carbon and HCρ by reaction with oil molecules. When a change in the envelope of the metal body (5a) occurs, the change in color can be observed from the outside through the observation window (4), so it is easy to check the degree of deterioration of the refrigerant without sampling the refrigerant from the refrigeration equipment. It will be detected.

In the invention of claim (2), the deterioration of the color of the metal body (5a) is detected by the change detection means (51), which is a more objective judgment than in the invention of claim (1). It becomes possible.

In the invention of claim (3), CD ions generated due to deterioration of the refrigerant cause the metal body (5b or 5
When c) corrodes and the metal wire becomes thinner and its electrical resistance increases, the change detection means (11) detects whether the change value is equal to or greater than a predetermined value, and objectively detects the degree of deterioration of the refrigerant. That will happen.

In the invention of claim (4), the above claim (2) or (3)
In addition to the above invention, when the electrical resistance of the metal body (5) deteriorates due to deterioration of the refrigerant due to /l'-U, CD ions, etc., the change is detected by the change detection means (]]), and the change is detected as a predetermined change. When the set value is exceeded, the signal output means (5
]) outputs the refrigerant deterioration fS number that indicates the time to replace the refrigerant, so it is possible to automatically know the time to replace the refrigerant. Therefore, if the refrigerant is operated with deteriorated refrigerant, the refrigeration capacity of the refrigeration system will be impaired. Therefore, the refrigerant replacement period can be determined without causing a decrease in the amount of refrigerant due to sampling to detect refrigerant deterioration. can be known.

In the invention of claim (5), the above claim fl], (21
, [3) or (4), the metal body (5) is disposed on the liquid pipe side of the condenser where the refrigerant is subject to thermal decomposition under conditions of high temperature and pressure. Changes in the color and electrical resistance of the metal body due to the deterioration of the cold tofu can be detected without causing false detections due to accumulation of water.

In the invention of claim (6), "2 claim (1), f2
), f3) or (4), the metal body (5) is placed in the high-pressure side where CD ions such as HCg generated by thermal decomposition of the refrigerant exist, so the above claim is met. The same effect as the invention of item (5) can be obtained.

In the invention of claim (7), the above claim fl), (2)
(3) Also, in the invention of (4), since the metal body (5) is placed in the reflux path from the Ura separator, which has many oil molecules and is likely to react with the refrigerant, the metal body due to deterioration of the refrigerant Deterioration in body color and electrical resistance values can be detected more quickly.

(Example) Hereinafter, an example of the present invention will be described based on the drawings from FIG. 2 onwards.

2 and 3 show the 1IVj arrangement of the refrigerant deterioration degree detection device of the first embodiment according to the invention of claim (1),
) is a sight glass as a refrigerant deterioration degree detection device to be placed in the refrigerant passage of a refrigeration system, and the sight glass (1) is equipped with a sight glass on the left and right sides of the main body (3) to connect with the refrigerant pipe. Equipped with joints t□ (2a) and (2b), the main body (
3) is provided with an observation window (4) for observing the inside. Then, 1-1 in the center of the main body (3)
A metal piece (5a), which is a metal body that is oxidized and discolored by HCl7 produced by deterioration of the refrigerant, is attached to the support part (6).
), and its color change can be observed from the outside with the naked eye. In this embodiment, the metal piece (5a) is made of an iron-based material with t+Vi, or is not necessarily limited to an iron-based material, as long as it changes color upon reaction with HCg.

That is, in the invention of claim (1), the metal piece (5a) is placed in the refrigerant passage of the refrigeration equipment, and the change in color can be observed from the outside through the observation window (4). , R12, R22, etc. decompose into unsaturated hydrocarbons, HC, and Q under high temperature conditions, etc., and are oxidized by the products of the reaction, HC and Q, resulting in discoloration.

For example, in the case of R-12, R-21, R, and -22, after reacting with oil molecules as shown in formulas (1) to (3) below, iron chloride and aluminum chloride are finally produced. It is considered to be a sign.

In the case of R-12, CCI・Fsu+R-C1l・-C111 → R-Cll
-C113+ elf CI P2(1)1] 0 In case of R-21, CII CI -P +R-C1lko-CI13→ R
-C1l-C1h +C112CIF [2]
In the case of CI R-22, CII CI P 2 +R-C112-C113→
R-C1l-0113+ClI2P
(3) Then, the chlorinated hydrocarbon formed as described above is decomposed as shown in equation (4).

R-Ctl-CH3→R-C11=CIlko-1-11
cI (4)1 Here, the unsaturated hydrocarbons generated above polymerize as shown in the following formula (5) and promote the darkening and carbonization of the oil. ) is thought to corrode metals.

n R-CH=CH2→(R-Cll-C1l: )
n (5)2HC1+Fe −= FeCl2
+Il: (6)2HCI+[O]
+2Cu→2CuCl+ 0 to 1 (7) 611Cl
+2Al→2AICI3 +311 (8
) 1 In other words, due to the above corrosion, the color of the metal piece (5a) changes, and when observed from the outside through the observation window (4), the degree of deterioration of the refrigerant can be determined by the color change of the metal piece (5a). can be detected depending on the Therefore, unlike conventional methods, there is no need to sample the refrigerant from the refrigeration system, so the degree of deterioration of the refrigerant can be detected without affecting the interior of the four refrigerant channels, such as the amount of refrigerant. The detection performance can be improved.

Next, a second embodiment of the invention according to claim (2) will be explained with reference to FIGS. 4 to 6. Figure 4 is the same as above.
This shows an example in which the sight glass (1) in the embodiment is equipped with an automatic detection device, and (7) is for covering the observation window (4) of the sight glass (1) to block the incidence of light from the outside. The cover moon (8) is placed inside the cover moon (7), and the LED emitting a constant amount of light (
Q ) is the metal piece (
The phototransistor serves as a change detection means for detecting a change in color of the metal piece (5a) due to deterioration of the refrigerant by measuring the intensity of the light reflected by the refrigerant (5a).

Further, FIG. 5 shows an electric circuit for detecting the refrigerant replacement 11:f period according to the output level Vin of the phototransistor (9), (11) is connected to the phototransistor (9), A comparator (12) for comparing the voltage V11 with the output Vin of the phototransistor (9) is connected to the comparator (11), and a user failure notification for notifying the user of a failure of the refrigeration system. The circuit (13) is also a comparator (]1
) is a fault diagnosis circuit for service personnel that notifies service personnel of refrigeration equipment failures. The comparator (11) is biased with a predetermined normal voltage Vn via an electric resistor (10) having a constant resistivity R.

That is, as shown in Fig. 6, when the metal piece (5a) discolors due to deterioration of the refrigerant and the reversal ratio decreases, the output level Vin of the phototransistor (9) gradually decreases and the above-mentioned over-standard voltage decreases. By comparing the level of the over-standard voltage Vn with the output Vin of the above-mentioned F1-1-range 3 star (9) and determining the point in time when the output level Vin becomes less than the reference voltage Vn, , the first period of refrigerant replacement is detected.

Therefore, in the invention of claim (2), when the refrigerant decomposes due to deterioration, the metal piece (5a) is oxidized by products such as HCp generated by the decomposition of the refrigerant, and the converter (change detection means) (51) oxidizes the metal piece (5a). A color change is detected. That is, it is possible to make a more objective judgment than in the invention of claim (1), and therefore, the performance of detecting the degree of deterioration of the refrigerant can be further improved as compared to the invention of claim (1).

Next, regarding the third embodiment according to the invention of claim (3),
This will be explained based on FIGS. 7 to 10. FIG. 7 shows a schematic structure of a detection device installed in a refrigerant passage, where (15) is a cylindrical case of the device, and (5b) is a metal wire as a metal body disposed inside the case (15). and the metal wire (
Both ends of 5b) are connected to predetermined measurement terminals (18a) (1
8b). In addition, as a metal body, instead of the metal wire (5b) 4, a metal piece (5C) having a constricted central part as shown in FIGS. 8A and 8B is used as a resin-covered plate ( 16) You may use the one taken from A/J.

Figure 9 shows l″J when using a metal piece (5c).
The outline of the motion detection device is shown in which one terminal (1, 8a) of the upper metal bending piece (5b) receives a constant pressure VO through a resistor (19) having a predetermined electric resistance. What power supply (2
0), and the other terminal (18b) is connected to a comparator (11) which determines the drawing of the stud (see FIG. 5) in the second embodiment. That is, the first
As shown in Figure 0, with CD ion centrality, the metal wire (5b)
Alternatively, when the electrical resistance R of the metal piece (5c) increases, the voltage applied to the metal wire (5b) or the metal piece (5C) increases, and as a result, the output level Vin to the comparator (11) decreases. Therefore, the output level Vin is equal to the standard voltage V
When the refrigerant becomes less than n, a refrigerant deterioration signal is output to the user's failure notification circuit (12) and the serviceman's failure diagnosis circuit (13) to notify that it is time to replace the refrigerant.

Therefore, in the invention of claim (3), the metal body (5b or 5c) disposed in the refrigerant passage is corroded by the CD ions generated due to deterioration of the refrigerant.
(see formula). When the metal wire becomes thinner due to corrosion (
For example, in the case of iron wire, 0. (It has been confirmed that corrosion of about 1 mm has progressed), and its electrical resistance increases, so the comparator (1) detects when the output level Vin, which has decreased due to this change, becomes less than the predetermined reference voltage Vn. Therefore, the degree of deterioration of the refrigerant can be objectively detected.

Next, the control contents according to the invention of claim (4) will be explained based on FIG. FIG. 11 is a flowchart showing a control procedure for notifying one period of refrigerant replacement that can be applied to both the second and third embodiments, in which a timer (not shown) is set in step S1. Wait until f4J has elapsed, sample the output level V 6 in at step S2, and then sample the output level V 6 in at step S4. From the comparison between the level Vin and the above-mentioned standard pressure Vn, it is determined whether the refrigerant has deteriorated or not.

Then, repeat the above steps until the refrigerant deteriorates,
When deterioration of the refrigerant is confirmed, the following signal is output as refrigerant deterioration f, . That is, in step S5, a user failure lamp (not shown) is lit, and in step S6, a serviceman failure lamp (not shown) is turned on. In the above flow, in step S5 or S6, a signal output means (51) is configured to receive the output of the change detection means (11) and output a refrigerant deterioration signal to notify deterioration of the refrigerant when the change value is greater than or equal to a predetermined value. has been done.

Therefore, in the invention of claim (4), when the electrical resistance of the metal body (5) is tabulated due to CD ions generated due to deterioration of the refrigerant, the change detection means (11) detects the change, and the change is detected and tabulated. When the temperature exceeds a predetermined set value, the signal output means (51) outputs a refrigerant deterioration signal indicating the time to replace the refrigerant, so that it is possible to automatically know when it is time to replace the refrigerant. Therefore, without reducing the amount of refrigerant due to sampling to detect refrigerant deterioration, it is possible to reliably know when to replace the refrigerant, and by operating the refrigerant with deteriorated refrigerant, the refrigerating capacity of the refrigeration system can be improved. It is possible to effectively prevent damage to the

Next, examples will be omitted or the inventions of claims (5) to (7) will be described.

In the invention of claim (5), the metal body (5) is arranged on the liquid pipe side of the condenser of the refrigeration system. Here, since the refrigerant is most susceptible to thermal decomposition under conditions of high temperature and high pressure, 0g ions are likely to be generated between the Hatake pressure line and the condenser. In addition, when detecting a change in the color of the metal object (5) by observation, etc., a similar change in color tone occurs due to the pores mixed in the refrigerant, so the refrigerant may be deteriorated. There is a risk of false detection that the refrigerant has deteriorated even though it is not present. On the other hand, if the refrigerant is placed on the liquid pipe side of the condenser, the refrigerant tends to have a thermal angle of 4" and is washed away by the liquid refrigerant, resulting in the above-mentioned false detection and separation. stomach.

Therefore, it is possible to invalidate the inventions of claims (1) to (4) above.

In the invention of claim (6), the metal body (5) is arranged in the liquid line on the high pressure side of the refrigeration system. Therefore, by the same effect as the invention of claim (5) above, it is possible to achieve the effectiveness of each of the above inventions.

In the invention of claim (7), the metal body (5) is arranged in the reflux path from the ura separator. Therefore, deterioration of the refrigerant is reliably detected in a place where there are many oil molecules and reactions with the refrigerant are likely to occur, and the above-mentioned inventions can be made more effective.

Note that the location of the metal body (5) is not limited to one location, but if the metal body (5) is disposed at several locations, deterioration of the refrigerant can be reliably detected.

(Effects of the Invention) As explained above, according to the invention of claim (1), a metal body is installed inside the refrigerant passage of a refrigeration system, an observation window is provided in the refrigerant passage, and the metal body is viewed from the outside. Since the change in color of the refrigerant can be observed, the degree of deterioration of the refrigerant can be determined without sampling and extracting the refrigerant from the refrigeration equipment, thereby improving the detection performance of the degree of deterioration of the refrigerant. I can do it.

According to the invention of claim (2), since a metal is disposed within the refrigerant passage of the refrigeration system and means for detecting a change in the color thereof is provided, the degree of deterioration of the refrigerant can be objectively determined. Therefore, it is possible to improve the detection performance of the degree of deterioration of the refrigerant.

According to the invention of claim (3), a predetermined 71 in the refrigerant passage.
A metal object is placed to determine the air resistance, and the degree of deterioration of the refrigerant is detected from the change in the air resistance. Therefore, the degree of deterioration of the refrigerant can be objectively determined. It is possible to improve the detection performance of the degree of deterioration.

According to the invention of claim (4), the above claim (2) or (
In the invention of 3), when the change in the characteristics of the metal body due to deterioration of the refrigerant exceeds a predetermined value, a signal is output to notify the deterioration of the a-medium, so that it is possible to automatically know when to replace the refrigerant. Therefore, it is possible to improve the performance of detecting the degree of deterioration of the refrigerant.

0 According to the invention of claim (5), the above claim (1), (
2).

In the invention of (3) or (4), since the metal body is placed on the liquid pipe side of the condenser, the metal body is placed in a place where deterioration of the refrigerant is likely to progress and therefore, metal change is likely to occur.
It is possible to achieve the effectiveness of each of the above inventions.

According to the invention of claim (6), the above-mentioned claim (1), (
In the invention of 2+(3) or (4), since the metal body is placed in the liquid line on the high pressure side, changes in the metal body due to deterioration of the refrigerant can be reliably detected, and therefore, the invention of claim (5) above is achieved. As with inventions, each invention can be made effective.

According to the invention of claim (7), the above claims (1) and (2)
), (3) or (4), since the metal body is placed in the reflux path of the oil separator, deterioration of the refrigerant can be quickly detected in locations where deterioration of the refrigerant is likely to occur due to reaction with oil molecules. Therefore, the effectiveness of each of the above inventions can be achieved.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention. 2 and 3 show a first embodiment of the present invention, 1. FIG. 2 is a partially cutaway front view of the sight glass, FIG. 3 is a plan view of the sight glass, and 4. ~Figure 6 is the second
4 is a partial cross-sectional view of a deterioration degree detection device in which a color change is detected by a phototransistor, and FIG.
The figure shows a schematic electrical circuit diagram of the detection circuit, and Figure 6 shows C.
Characteristic diagrams showing changes in phototransistor output level with respect to changes in D ion concentration, FIGS. 7 to 10 show the third embodiment, and FIG. 7 shows refrigerant deterioration degree detection based on changes in electrical resistance. A partial sectional view of the device, FIGS. 8A and 8B are a side view and a front view, respectively, of a metal piece module that can be placed in place of the metal wire in FIG. Circuit diagram, Figure 10 is Cβ
FIG. 11 is a characteristic diagram showing the change characteristics of the electrical resistance value with respect to the change in ion concentration, and a flowchart showing the control contents for detecting the refrigerant replacement timing in the second embodiment and the third embodiment. 4 observation windows 5a, 5c metal pieces 2 5b] 1 metal wire comparator (change detection means) 1 signal output means

Claims (7)

[Claims] (1) A metal body (5a
), and an observation window (4) provided in the refrigerant passage corresponding to the arrangement position of the metal body (5a) for observing a change in color of the metal body (5a) due to deterioration of the refrigerant. A refrigerant deterioration degree detection device for a refrigeration system, characterized in that: (2) A metal body (5a
); and change detection means (11) for detecting a change in color of the metal body (5a) due to deterioration of the refrigerant. (3) A metal body (5b
or 6c), and change detection means (1) for detecting a change in electrical resistance of the metal body (5b or 5c) due to deterioration of the refrigerant.
1) A refrigerant deterioration degree detection device for a refrigeration system, characterized by comprising: (4) A claim characterized by comprising a signal output means (51) that receives the output of the change detection means (11) and outputs a refrigerant deterioration signal to notify deterioration of the refrigerant when the change value is equal to or greater than a predetermined value. A refrigerant deterioration degree detection device for a refrigeration system according to item (2) or (3). (5) Claims (1), (2), (1) characterized in that the metal body (5) is disposed on the liquid pipe side of the condenser of the refrigeration system.
3) or (4) refrigerant deterioration degree detection device for a refrigeration system. (6) Claims (1) and (2), characterized in that the metal body (5) is disposed in a liquid line on the high pressure side of the refrigeration system.
A refrigerant deterioration degree detection device for a refrigeration system according to (3) or (4). (7) The refrigeration equipment is equipped with an oil separator for separating oil in the gas discharged from the compressor and returning it to the compressor, and the metal body (5) is connected to the return path from the oil separator. A refrigerant deterioration degree detecting device for a refrigeration system according to claim 1, wherein the refrigerant deterioration degree detecting device is arranged in a refrigeration system.