Capacitive sensor for detecting material level of grain dryer

Abstract

The invention discloses a capacitive sensor for detecting the material level of a grain dryer. The capacitive sensor mainly comprises a circuit board, a metal rope, a positive pole for mutual capacitive induction and negative poles located on the two sides of the positive pole; the positive pole and the negative poles are connected through connecting pieces, and the two sides of the negative polesare fixed through a left fixing piece and a right fixing piece correspondingly; the metal rope sequentially penetrates through the left fixing piece, one of the negative poles, one of the connectingpieces, the positive pole, the other connecting piece, the other negative pole and the right fixing piece; and the circuit board is located on the left fixing piece or the right fixing piece, and is connected with the positive pole and the two negative poles through wires. The capacitive sensor is of a cylindrical capacitor structure, the material level is determined by measuring whether grain exists at each sensor position or not, real-time online monitoring can be achieved, and the full-bin state is detected timely; and the multiple sensors are finally connected in series to be subjected toplastic package in a PVC outer skin so as to be made in a flexible cable form, rusting is avoided, the surface is smooth and has no mixed powder, segmented continuous measurement is achieved, measurement accuracy is high, the structure is simple, mounting is convenient, and the influences of the bin structure and the mounting environment are avoided.

Description

technical field [0001] The invention relates to the field of measuring instruments, in particular to a capacitive sensor for detecting the material level of a grain dryer. Background technique [0002] At present, most grain dryers only rely on the anti-rotary material level switch installed on the top of the warehouse to determine whether the warehouse is full. Once there is a problem with the material level switch, it is easy to load too much grain and cause the machine to malfunction. When it is full, it is also difficult to control the grain level in the warehouse. [0003] The capacitive material position sensor (material level sensor) based on the principle of capacitance measurement is one of the sensors widely used in material level measurement. Using the material in the silo as the dielectric, the use of capacitive sensors to detect the material in the tall silo is one of the more convenient and practical means at present. At present, there are many kinds of mater...

AI Technical Summary

Problems solved by technology

At present, there are many kinds of material level sensors at home and abroad, including segmental capacitive sensors composed of electrodes and the silo wall of the measured silo. When the position in the warehouse changes with the movement of the material, the measurement results also change accordingly; the "string candied haws" type segmented capacitive sensor has a complex structure and is easily limited by the height parameters of the material. The measurement accuracy is more difficult to meet the user's requirements; the tube-type material level sensor, based on the principle that the height of the material is proportional to the output capacitance signal, as long as the output value of the capacitance at this terminal is detected, the height of the material can be determined. The gap between the concentrated pole and the polarized pole is limited by the site conditions, which may cause material inclusions and affect the detection results and normal operation of the detector.

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