JPH03213972A - Refrigerator - Google Patents

Abstract

PURPOSE:To protect an incombustible refrigerant including fluorine excellent in a freezing figure of merit from firing or explosion by providing refrigerant leakage detector means and a refrigerant leakage control device or alarming said detector means. CONSTITUTION:There are provided a catalyst heater 12 for thermally decomposing an incombustible refrigerant including a fluorine element at a low temperature and an electrically conductive compound 8 including monovalent or divalent metal which reacts with a fluorine element produced by thermal decomposition. Further, there are provided detector means 10 for detecting that the conductive compound 8 changes to non-conductive one by reaction, and a refrigerant leakage control device 5 provided on the bottom of a refrigerator 1 in the same which device 5 comprises alarm control means for supplying power to an alarming buzzer 11 connected to the detector means 10. Hereby, even if refrigerant including fluorine leaks from a freezing cycle piping part or an evaporator in the refrigerator 1, refrigerant with large specific gravity naturally flows into the refrigerant leakage control device 5, and makes contact with a heater 12 for thermal decomposition. Fluorine element with small specific gravity so thermally decomposed reacts with the conductive compound 8 and is passivated to issue alarm.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a refrigerator using a flammable refrigerant.

Prior Art The refrigerant used in conventional refrigerators is trichlorofluoromethane (R-12), which is non-toxic, safe, nonflammable, and has excellent refrigerating capacity and coefficient of performance.
Due to CFC regulations, this refrigerant cannot be used in the future.

Therefore, in recent years, R-152a, R-152a /
R-22, R-152a/R-134a.

R-162a/R-22/R-124 and the like have been proposed. In particular, R-152a has an evaporation temperature of -3oC.

It has been confirmed that the amount of consumed energy under the conditions of an actual refrigerator, such as a condensing temperature of 30° C., is superior to R-12 by 10% or more.

Problems to be Solved by the Invention However, since R-152a is a flammable refrigerant, in the actual use of a refrigerator, if the refrigerant leaks from a part of the refrigeration cycle, especially from a part of the evaporator, R-152a may be present inside the refrigerator. 1
It is not used as a refrigerant for refrigerators because R-162a gas accumulates and easily reaches the flammable range of 14 mO1% to 46 mO1%, which is the flammable range of R-162a, and there is a high risk of explosion or fire. Ta.

On the other hand, sensors that detect hydrocarbons such as propane gas, which are commonly used as a means of detecting flammable gases and taking some countermeasures before the concentration reaches outside the flammable range (VO1%) However, since this sensor is a semiconductor sensor with NTC characteristics that utilizes the heat of combustion of hydrocarbons, it uses compounds containing fluorine (R-
162a), it was not possible to detect a trace amount of R-152a gas because the amount of heat for thermally decomposing R-152a was very high and the amount of combustion heat was small.

In view of the above points, the present invention provides a refrigerator configured with a refrigeration cycle using a flammable refrigerant or a mixed refrigerant containing a flammable refrigerant that has an excellent refrigeration coefficient of performance.

Means for Solving the Problem As a means for detecting a flammable refrigerant containing fluorine, a catalyst that thermally decomposes the flammable refrigerant containing fluorine at low temperature and a conductive compound containing a monovalent or divalent metal that reacts with the decomposed fluorine are used. Fluorine detection means consisting of.

A refrigerator consisting of a refrigerant leak alarm control device that notifies you of a leak after detecting fluorine.

During actual use of the refrigerator, S-162 is removed from the evaporator that makes up the refrigeration cycle or from a part of the refrigerant piping installed inside the refrigerator.
If a refrigerant for refrigeration using a refrigerant or a mixed refrigerant containing R-152a leaks, the flammable refrigerant containing fluorine will be thermally decomposed at low temperature using a thermal decomposition catalyst to generate fluorine gas, and the fluorine component and 1 Conductive compounds containing valent or divalent metals react to produce metal fluoride compounds. The initial resistivity value of a compound containing a monovalent or divalent metal is 1
The value is very low because valent or divalent metals are good conductors. When it becomes a metal fluoride compound, the specific resistance value increases significantly because metal fluoride is a non-conductor, and this electrical property is used to issue an alarm, alerting people that flammable refrigerant has leaked and preventing a fire or explosion. This eliminates the danger of

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a refrigerator in an embodiment of the present invention. 1 is a refrigerator, 2 is a compressor, and 3. This is an evaporator connected to a condenser 4 and piping.

Reference numeral 6 denotes a detection device and an alarm buzzer for detecting the refrigerant leaking from the evaporator 2 using a flammable refrigerant such as R-152a in the refrigeration cycle of the refrigerator 1 or from the refrigerant piping installed inside the refrigerator 1. This is an integrated refrigerant leak alarm control device. The refrigerant leak alarm control device 6 is provided in the lower part of the refrigerator 1 because the specific gravity of refrigerant such as R-152a is heavier than air.

FIG. 2 is an example of a specific electric circuit. 6 is a DC power supply circuit connected to the primary power outlet, and 7 is a refrigerant leak alarm control electric circuit.

Ga-A s containing sodium or potassium element
A relay 9 connected in series to a conductive compound 8 containing Na or zeolite made of a semiconductor or zeolite is connected, a contact switch 1o and an alarm buzzer 11 are connected in series, and a heater 12 made of a platinum catalyst is connected to the DC power supply circuit. 6
connected via.

The heater 12 is always energized and has a temperature of 260 to 30
It is maintained at 0°C. Flammable cold containing fluorine [R-1
When 52a comes into contact with the heater 12, it is thermally decomposed due to the platinum catalytic effect and elemental fluorine is generated. When elemental fluorine comes into contact with the conductive compound 8 containing Na or K, which is highly reactive with elemental fluorine, it reacts quickly and changes to NaF or KF, thereby increasing the specific resistance of the conductive compound containing Na or K. The specific resistance of K-containing zeolite is 1~2x10'-60-cm, 10"Q after reaction.
- Changes by more than cwr. Contact switch 1o is relay 9
It is kept open at all times by NaF or KF.
When the current changes to , the current to the relay 9 is stopped, and the connected switch 10 is turned on and energized. Alarm buzzer 1 when energized
A current is input to 1, and the alarm buzzer issues an alarm. The conductive compound 8 containing Na or fluorine may be a semiconductor or zeolite containing a divalent metal such as Ca, although the reaction with fluorine is rather slow.

FIG. 3 is a cross section of a main part of the refrigerant leak alarm control device installed at the bottom of the refrigerator 1. A conductive compound 8 containing Na or ions is formed as a thin film on an insulator 13 such as ceramic on the heater 12 side. Terminals 14 and 15 of the conductive compound 8 containing oxygen, Na or the like are connected to the relay 9 and the DC power supply circuit 6. Reference numeral 12 denotes a heater such as the platinum catalyst, which is connected in series to the DC power supply circuit 6.

16 is the DC power supply circuit 6 and the alarm buzzer 11. This is a control device with a built-in contact switch 1o. 17 is R-15
When the refrigerant 2a etc. leaks from a part of the piping of the evaporator 2 etc. of the refrigerator 1, it is a flow passage hole that is introduced into the heater 12, and is arranged so that the opening surface is upward. Reference numeral 18 denotes an outflow hole through which hydrocarbon gas generated after the refrigerant is thermally decomposed or partially undecomposed refrigerant flows out. Similarly, reference numeral 19 designates an opening hole through which the leaked refrigerant is guided to the heater 12 in the ceramic insulating material 13 in which a thin film of a conductive compound containing Na or a conductive compound is formed.

As described above, according to this embodiment, when refrigerant leaks from a part of the piping and evaporator that form the refrigeration cycle in one refrigerator, R-152a or a mixed refrigerant containing R-152a is released from air. Since the specific gravity is approximately 10% larger, the passage hole 1 provided in the refrigerant leak alarm control device installed at the bottom of the refrigerator 1 is moved to the bottom of the refrigerator 1.
7, the refrigerant flows into the heater 1 through the opening hole 19.
2, where it is thermally decomposed. Because the thermally decomposed fluorine element has a lower specific gravity than air, it rises to the upper surface of the inside of the refrigerator. The elevated fluorine element is removed from the Na or conductive compound 8 formed on the insulator 13 such as ceramic.
immediately reacts with Na or K to form NaF
Alternatively, KF is generated and becomes a nonconductor. The conductive compound 8 containing Na or R-152a has a concentration of 100
Since the amount of Na or K is set to such an amount that all reactions are completed below 0 ppm (/vo 1%), the relay 9 is connected to the energized state and conduction is stopped, and when the relay 9 is closed, the contact switch 1o turns on the alarm buzzer. 11 is turned ON and an alarm is issued.

Effects of the Invention As described above, the present invention provides a catalytic heater that thermally decomposes a flammable refrigerant containing fluorine element at a low temperature, a conductive compound containing a monovalent or divalent metal that reacts with the fluorine element generated by the thermal decomposition, A refrigerant leakage control device consisting of a detection means in which the conductive compound becomes a non-conductor by reaction, and an alarm control means for energizing an alarm buzzer connected to the detection means is provided at the bottom of the refrigerator. When refrigerant leaks from the refrigeration cycle piping inside the refrigerator or the evaporator, the refrigerant with a higher specific gravity naturally flows into the refrigerant leakage control device and is catalytically pyrolyzed by the heater, whereupon the refrigerant with a lighter specific gravity is pyrolyzed. Fluorine element reacts with the conductive compound to become a nonconductor and can issue an alarm.Flammable refrigerants containing fluorine, which have an excellent coefficient of refrigeration performance, can be prevented from fire or explosion, and platinum etc. can be used as heater sources. Because it has a structure that allows thermal decomposition at low temperatures with a catalytic action, it consumes less electricity and less heat flows into the refrigerator, which has great practical effects.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a refrigerator equipped with a refrigerant leakage control device showing one embodiment of the present invention, and FIG. 2 is an electric circuit diagram of the device.
FIG. 3 is a block diagram of the main parts of the device. 1... Refrigerator, 5... Refrigerant leakage control device, 6... DC power supply circuit, 8... Conductive compound, 11... Alarm Buzzer, 12...
·heater

Claims (2)

[Claims] (1) A refrigerator, in a refrigeration cycle using a combustible refrigerant containing fluorine, including a refrigerant leak detection means and a refrigerant leak control device that alarms the detection means. (2) a catalytic heater that thermally decomposes a flammable refrigerant containing elemental fluorine at low temperatures; a conductive compound containing a monovalent or divalent metal that reacts with the elemental fluorine generated by the thermal decomposition; a detection means that is a nonconductor;
A refrigerator provided with a refrigerant leakage control device comprising an alarm control means that energizes an alarm buzzer connected to the detection means.