RU-2861477-C1 - SENSOR FOR DETECTING PRESENCE OF FLOW OF BULK MATERIAL ON CONVEYOR BELT

Abstract

FIELD: detection means. SUBSTANCE: sensor for detecting the presence of a flow of bulk material on a conveyor belt comprises a microwave generator, a frequency meter, and a transmitter for transmitting a microwave signal, a microwave signal receiver, a microwave signal difference unit, and a tee. The output of the microwave generator is connected to the first arm of the tee. The second arm of the tee is connected to the transmitter for transmitting the microwave signal. The output of the microwave signal receiver is connected to the first input of the microwave signal difference unit. The second input of the microwave signal difference unit is connected to the third arm of the tee. The output of the difference unit is connected to the input of the frequency meter. The microwave generator, tee, transmitter and receiver are located on the outer surface of a first rectangular plate fixed vertically on the side of the conveyor housing opposite a second rectangular plate fixed vertically diametrically on the side of the conveyor housing. The heights of the fixed rectangular plates are not less than the height of the flow of bulk material on the conveyor belt. EFFECT: simplification of the process of detecting the presence of a flow of bulk material on a conveyor belt. 1 cl, 1 dwg

Inventors

• Akhobadze Gurami Nikolaevich

Dates

Publication Date

20260505

Application Date

20250828

Claims (1)

1. A sensor for detecting the presence of a flow of bulk material on a conveyor belt, comprising a microwave generator, a frequency meter and an emitter for transmitting a microwave signal, characterized in that it further comprises a microwave signal receiver, a microwave signal difference unit and a tee, wherein the output of the microwave generator is connected to the first arm of the tee, the second arm of the tee is connected to the emitter for transmitting the microwave signal, the output of the microwave signal receiver is connected to the first input of the microwave signal difference unit, the second input of the microwave signal difference unit is connected to the third arm of the tee, the output of the difference unit is connected to the input of the frequency meter, wherein the microwave generator, tee, emitter and receiver are located on the outer surface of the first rectangular plate, fixed vertically to the side of the conveyor body opposite to the second rectangular plate, fixed diametrically vertically to the side of the conveyor body, wherein the heights of the fixed rectangular plates are not less than the height of the flow of bulk material on the conveyor belt.

Description

The invention relates to the field of conveyor engineering, in particular to devices for monitoring the presence of material on a belt. A device for monitoring the presence of material on a conveyor belt is known (see SU 267446 A1, 01.04.1970), comprising a first blade deflected by the material, secured to a rod pivotally mounted on a frame and interacting with a limit switch, and a second blade, both blades being rotatable on their rods in a plane parallel to the plane of the belt and located on the sides of the belt, overlapping it when there is no material on it and diverging to the sides when there is material on the moving belt. Material moving on the conveyor belt acts on the blades and spreads them apart. The blades, through holders, act on the rods, which activate limit switches. The limit switches close an alarm circuit indicating that there is material on the conveyor belt. The disadvantage of this well-known technical solution is the breakage and wear of the blades due to the abrasiveness of the materials controlled on the belt. A device for monitoring the flow of bulk material on a conveyor belt is known (see SU 1184752 A1, 15.10.1985), comprising a material leveler, followed by a rolling roller capable of rotation in a vertical plane and a platform with a material quality control sensor capable of vertical movement, installed along the conveyor belt. The platform is designed as two rollers arranged parallel to the rolling roller and connected to each other by an axis with a gap relative to each other, in which a material quality control sensor is located with a gap relative to the monitored surface of the bulk material flow. Furthermore, to improve the operating conditions of the sensor and its safety, the gap between the sensor and the monitored surface of the bulk material flow along the perimeter of the rollers is filled with a material that weakly absorbs fluorescent radiation. The disadvantages of this well-known device include the complexity of the processes of leveling, compacting and smoothing the flow of material with a rolling roller, as well as ensuring a constant distance from the quality control sensor to the surface of the controlled layer of material. The closest technical solution to the proposed sensor is the MWS-DP-3 microwave flow sensor (see the website: rusautomation.ru), which the author used as a prototype. It is designed to detect flow on a conveyor belt. This sensor operates using microwave radiation and utilizes the Doppler effect, which emits low-power microwave radiation toward the target material. Part of this radiation is reflected back to the sensor's sensitive element, and the device then analyzes whether the reflected signal originates from a stationary or moving object. If the reflected signal has a Doppler frequency shift, flow on the conveyor belt is detected. A disadvantage of this well-known technical solution is the difficulty of isolating the Doppler frequency when the reflected and reference microwave signals are shifted in the presence of external interference in the form of electromagnetic fields and ambient noise. The technical result of the claimed sensor is to simplify the process of determining the presence of a flow of bulk material on a conveyor belt. The technical result is achieved in that the sensor for detecting the presence of a flow of bulk material on a conveyor belt, comprising a microwave generator, a frequency meter and an emitter for transmitting a microwave signal, additionally comprises a microwave signal receiver, a microwave signal difference unit and a tee, wherein the output of the microwave generator is connected to the first arm of the tee, the second arm of the tee is connected to the emitter for transmitting the microwave signal, the output of the microwave signal receiver is connected to the first input of the microwave signal difference unit, the second input of the microwave signal difference unit is connected to the third arm of the tee, the output of the difference unit is connected to the input of the frequency meter, wherein the microwave generator, tee, emitter and receiver are located on the outer surface of the first rectangular plate, fixed vertically to the side of the conveyor body opposite the second rectangular plate, diametrically fixed vertically to the side of the conveyor body, wherein the heights of the rectangular plates must be equal to the height of the flow of bulk material on the conveyor belt. The essence of the claimed invention, characterized by the combination of the above-mentioned features, is that by measuring the characteristics of a standing wave formed between the first dielectric plate and a layer of controlled flow of bulk material on a conveyor belt, it is possible to ensure the presence of a flow of bulk material on the conveyor belt. The presence of the set of listed existing features in the claimed device allows solving the problem of determining the presence of a flow of bulk material