JPS58178171A - Detecting sensor for clogging of frost for refrigerator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to detecting frost clogging in a refrigerator evaporator by utilizing the wind speed difference and temperature system that change depending on the amount of frost. It is an object of the present invention to provide a frost clogging detection sensor that solves malfunctions and improves the reliability of frost formation detection.

Conventional refrigerator box clogging detection involves defrosting by measuring the accumulated time of actual operation of the compressor placed in the refrigerator with a timer and outputting an input signal to the defrosting heater. The amount of frost on the refrigerator evaporator varies depending on the setting environment and historical behavior, and with a fixed integration timer method, the defrost heater is activated regardless of the amount of frost, heating and recooling the evaporator. This has been a flaw in terms of efficiency and power conservation as it increases the frequency of

The present invention has been made to improve the above-mentioned defects. In other words, it increases the amount of frost that has formed on the evaporator to a range that does not reduce the cooling effect, and detects the actual amount of frost, thereby reducing the frequency of defrosting and reducing the power consumption of the refrigerator. .

This invention focuses on the fact that a single detection method such as a temperature difference detection method or a wind speed difference detection method has many causes of malfunction, and has developed a method to replace the general frosting phenomenon of evaporators that occurs in practical operation. It is set to detect temperature differences and wind speed differences to detect frost clogging, and is configured so that even if one of them malfunctions temporarily, a frost clogging signal will not be generated. To improve reliability and perform proper defrosting operation.

An embodiment of the present invention will be described below with reference to FIGS. 1, 2, and 3. In a refrigerator in which the air cooled by the evaporator 1 is forcedly circulated from the refrigerator compartment 11 through the return duct 8 to the freezer compartment 3 and the refrigerator compartment 11 by the fan 2, the downward direction of the refrigerant vibrator 4 of the evaporator 1 is 2 to 10wn. A temperature detection element 9 is disposed opposite the return duct 5 of the refrigerator compartment, and a temperature detection element 8 is disposed inside the return duct 5.In addition, the wind speed detection elements R-6 and 7 are disposed opposite the return duct 5 of the refrigerator compartment. and one at the discharge port. When the output difference of each detection element changes to the set value shown in FIG. 2, the signals ', 4i11 shown in FIG.
A frost blockage signal is generated by three comparators 12,13. The temperature difference signal and the wind speed difference signal are simultaneously input to the AND circuit 14 to output a defrosting operation signal. According to this embodiment, the detection of the amount of frost can be optimized by overcoming the malfunction of the independent detection method of wind speed difference and temperature difference in the case of disturbances such as door opening or large amounts of food being thrown in.

According to the present invention, since the structure is configured to generate a frost clogging signal by detecting the difference in wind speed and temperature, a predetermined amount of 1'V of frost is generated regardless of temperature changes due to opening/closing of the door or food being put in. As for the temperature sensing element r-, it was decided to use a small chip thermistor due to its mounting position and detection speed.

In addition, if water droplets accumulate on the surface of the wind speed sensor, a detection error will occur, so when detecting the evaporator suction wind speed, we installed it inside the refrigerator compartment return duct, avoiding directly beneath the evaporator, to prevent water droplets and stabilize operation.

[Brief explanation of the drawing]

Figure 1 is a side view of the installation position of the wind speed detection element and temperature detection element according to the present invention installed near the evaporator, and Figure 2 is a plot of changes in the measured difference between wind speed and temperature as frost builds up. The explanatory diagram shown in FIG. 3 is an electric circuit diagram. 1... Evaporator, 2... Fan, 3... Freezer, 4
... Refrigerant pipe, 5... Refrigerator compartment return duct, 6.7
...Wind speed detection element, 8.9...Temperature detection element, 10
... Door, 11... Refrigerator room, 12.13... Signal voltage comparator, 14... AND circuit. Representative Patent Attorney Susuki [Jl Profit%”' No./Fig. Frost □ Fig. 3 12 Snow clogged signal

Claims (1)

[Claims] 1. In a sensor for detecting frost clogging in a refrigerator evaporator that uses a fan to forcefully circulate indoor air, wind speed detection elements are provided on the air suction side and the discharge side of the evaporator, and Temperature detection elements are installed in the space near the container and in the return air suction duct in the refrigerator compartment, and when the signal level difference between the two wind speed detection elements in O1I reaches the set value, the wind speed difference signal output and the temperature difference signal output are output. Assuming that the AND circuit is manually operated, the corresponding A
A refrigerator box clogging detection sensor that uses the output of the ND circuit as a frost clogging signal for the evaporator. 2. A wind speed detection element (6) is provided in the lower part of the evaporator facing the return duct on the refrigerator compartment side among the return air ducts of each of the freezer compartment and the refrigerator compartment provided at the lower part of the evaporator (1). A box jam detection sensor for a refrigerator according to claim 1. 3. Among the return air ducts for each of the freezing and refrigeration compartments provided below iη[9 of the evaporator (1), a temperature detection element (9) is installed at the bottom of the evaporator facing the return duct on the refrigeration Y side.
A box jam detection sensor for a refrigerator according to claim 1, characterized in that the sensor is provided with: