METHOD AND APPARATUS FOR MEASURING MOISTURE IN BULK MATERIAL USING ELECTRICITY

PURPOSE:To make it possible to perform highly reliable measurement, in which transmission of information between a sensor part and a main body is ensured, by detecting the electric characteristics of a bulk material with a moisture measuring sensor part, and transmitting the values to the main body through a radio system. CONSTITUTION:A moisture measuring device is composed of a main body 4 and a moisture measuring sensor part 5, which can be separated from the main body 4. In the sensor part 5, the electric characteristics of a material to be measured such as electrostatic capacitance and other data, which are measured by a measuring part 12, are inputted to a multiplexer 23. The multiplexer 23 sequentially outputs these data to a voltage-frequency converter 13 as a voltage level. The converter 13 changes the output frequency in accordance with the value of the input voltage. The output V1 from the converter 13 is modulated by an intermittent carrier wave V2 from a carrier wave generator 16, in a modulator 14. The modulated signal is transmitted from a transmitting antenna 10. The signal is received by a receiving antenna 11' in the main body 4 and amplified by a high frequency amplifier with bandpass filter 21 and detected by a detector 20. The result is inputted to a microcomputer 19. Based on temperature correction, load correction and the electrostatic capacitance of the material to be measured, computation and the like for moisture percentage are carried out. The result is outputted to an external printer or displayed on an LCD display 18.