Application of Infrared Body Sensors in microwave oven
The Infrared Body Sensors in our normal life is very widely used, such as indoor air conditioning, refrigerators and microwave ovens and other household appliances, and how to determine the microwave inside the food is hot enough and will not burn it? This requires the use of Infrared Body Sensorss. The probe is equipped with a Infrared Body Sensors at the bottom of the microwave oven. It can identify the initial temperature and have multiple probes in the internal space to detect the internal temperature and communicate to the bottom probe, and precisely control the temperature. And requires a high-performance, stable structure, can be anti-magnetic interference of the Infrared Body Sensors.
Infrared Body Sensors in the microwave oven is the use of thermistor changes with the characteristics of the temperature changes, the power of the electromotive force E = 9.0V, the internal resistance is negligible; G for the sensitive current meter, the internal resistance Rg remain unchanged; R is hot Resistance, closed switch S, when the temperature of R is equal to 20 ℃, the ammeter I1 = 2mA, when the ammeter reading is I2 = 3.6mA, the temperature of the thermistor R.
A Infrared Body Sensors structure of a microwave oven includes a sensor probe, a sensor housing, a probe head hole, and a plurality of inside of the lower cover of the housing are provided with a plurality of support posts for supporting the sensor probe, the top of the part of the support column is provided with a raised position The positioning pin and the positioning hole are matched with each other when the sensor probe is loaded into the sensor housing, and the positioning pin is positioned corresponding to the positioning pin. The bottom of the inner space of the lower cover of the housing is provided with a protruding locating plate; The position of the sensor probe is accurate, so that the position of the probe head and the probe head at the bottom of the shell cover each other accurately, to avoid deviation, but also to simplify the production and installation process, further cost savings and improve production efficiency.
With the rapid development of fiber infrared infrared sensor, microwave ovens have begun to use a large number of fiber infrared sensor, because the fiber body infrared sensor in the microwave environment is very applicable. The advantage of this temperature sensing system is that it eliminates the string light between adjacent sensor heads and reduces measurement errors to achieve higher resolution and accuracy. The inadequacy of the place is more expensive. This greatly limits its application in the microwave. So now generally only relatively high-end microwave oven only use the fiber body infrared sensor.
Said in the microwave which the Infrared Body Sensors is essential, a safe and sensitive instrument can be a good protection of the user's life safety and property safety.
Today we have a simple talk about the Infrared Body Sensors fault detection: the current market, more types of Infrared Body Sensorss, according to its structure and shape can be roughly divided into spherical, rod-shaped, tubular, round, circle Shape and so on. And then we in accordance with the different ways of heating can be divided into direct thermal infrared body sensors and bypass thermal infrared sensor. At the same time in accordance with the working temperature range can be divided into room temperature, high temperature, ultra-low temperature thermistor. According to the temperature coefficient can be divided into positive temperature coefficient thermistor and negative temperature coefficient of Infrared Body Sensors.
(1) First of all, we look at the appearance of the Infrared Body Sensors. Potentiometer or Infrared Body Sensors must be marked clearly, the solder plate or pin without corrosion, rotary shaft rotation flexibility, elastic appropriate, rotating feel is smooth, and no mechanical noise and jitter phenomenon.
(2) the use of hand gently shake the potentiometer or Infrared Body Sensors pin, there should be no loose phenomenon.
(3) the multimeter resistance block to the appropriate range, and then we are in the ohm zero, and finally the use of two test leads (regardless of positive and negative) and resistors are connected at both ends of the pin, so that you can measure the actual Of the resistance value. Finally, the test value and the nominal value of the resistor to check, which can be a good judge whether the potentiometer or Infrared Body Sensors is intact. If the multimeter pointer is immobile, then it means that the internal resistor and disconnected.