RU2746391C1 - Device for discrete measurement of the level of bulk products in the bunker - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: invention relates to agriculture, in particular to measuring devices designed to measure the level of bulk products in a bunker, and can be used in agricultural, food, chemical and other industries, where there is a need to measure the volume of bulk products loaded into bins, tanks, storage, etc. In a device for discrete measurement of the level of bulk products in a bunker, containing sequentially located level sensors connected to the signal processing circuit, according to the solution, capacitive sensors with a normally closed output are used as sensors, the device additionally contains a GPS terminal connected to the output of the signal processing circuit, containing a reference voltage source connected to a reference resistor, which is connected to a set of resistive dividers, each of which is connected to the sensor output, while the number of dividers is a multiple of the number of sensors, while some of the sensors are rigidly fixed along one of the walls of the bin, and others along the bottom. Capacitive sensors are fixed to the bunker surface with screws.

EFFECT: possibility of on-line control of the level of bulk product in the bunker due to the formation of an analog signal level.

1 cl, 4 dwg, 1 tbl

Description

The invention relates to agriculture, in particular to measuring devices designed to measure the level of bulk products in a bunker, and can be used in agricultural, food, chemical and other industries, where there is a need to measure the volume of bulk products loaded into bins, tanks, storage etc.

A device for measuring the level of bulk materials is known (copyright certificate SU 750281, IPC G01F 23/18). The device contains a probe suspended on a cable passing through a weight lever roller, an electric drive with two amplifiers and an input inverter connected to a cable tension sensor and through intermediate inverters with control circuits, lowering and lifting the probe with a time element in the lifting circuit. The probe lowering control circuit is made in the form of two series-connected inverters and a time element connected between one amplifier and an intermediate inverter of the probe lowering control circuit, and the probe lifting control circuit is made in the form of two series-connected inverters, a memory cell and an inverter connected between another amplifier and an intermediate inverter of the probe lifting control circuit, which is connected to an inverter of the probe lowering control circuit, connected to an intermediate inverter of the same circuit and an amplifier of the probe lifting control circuit, the memory cell being connected to the time element.

The disadvantage is the presence of moving parts, leading to a low accuracy of control of the amount of material in the hopper.

A device for controlling the amount of material in the hopper is known (copyright certificate SU No. 1781150, IPC B65G 65/30, G01G 11/04). A weighing element is installed in the hopper, containing a weight sensor - a strain gauge (TD), a support bar with plates rigidly fixed to it at different levels. The boom rests on the TD located on the hopper. The TD is enclosed in a protective casing that protects it from external forces. The signal goes directly to the strain gauge on the shield through a strain gauge transducer to any indicating, recording device that receives an analog infected electrical signal. If necessary, this unified electrical signal can be fed to the automated process control system of the computer.

The disadvantage is the complexity of the design and the impossibility of online control.

Closest to the claimed device is a device for discrete level measurement (patent RU No. 2010175, IPC G01F 23/00), containing sequentially located sensors and a signal processing circuit. The signal processing circuit is made in the form of a transmission-reception unit and a series-connected computer interface unit and a control panel, the output of which is connected to the control input of the transmission-reception unit, the information and control outputs of which are connected, respectively, to the second input of the control panel and the input of the computer interface unit , while each sensor, starting with the second, is connected to the previous and next, and the inputs of the first and the outputs of the last sensors are connected, respectively, to the outputs and inputs of the transmission-reception unit.

The disadvantage is the impossibility of online control.

The technical problem is to expand the arsenal of devices that allow you to control the level of bulk products in the bunker.

The technical result consists in the possibility of on-line control of the level of bulk product in the bunker due to the formation of an analog signal level.

To solve the technical problem and achieve the claimed result in a device for discrete measurement of the level of bulk products in a bunker containing sequentially located level sensors connected to a signal processing circuit, according to the solution, capacitive sensors with a normally closed output are used as sensors, the device additionally contains a GPS terminal connected to the output of a signal processing circuit containing a reference voltage source connected to a reference resistor, which is connected to a set of resistive dividers, each of which is connected to the sensor output, while the number of dividers is a multiple of the number of sensors, while some of the sensors are rigidly fixed along one from the walls of the bunker, and others along the bottom.

Capacitive sensors are fixed to the hopper surface with screws.

The device is illustrated by drawings, where:

in fig. 1 - the structure of the claimed device is shown;

in fig. 2 - electrical circuit for signal processing with connected capacitive sensors;

in fig. 3 is a schematic diagram of the device;

in fig. 4 is a graph of the dependence of the change in the grain level in the bunker of the combine during harvesting.

Positions in the drawings indicate:

1. Grain bin,

2. Capacitive sensors with normally closed output,

3. Signal processing circuit,

4. GPS terminal,

5. Harness of wires connecting sensors to the electronic unit,

6. Reference voltage source U _op .,

7. The reference resistor of the voltage divider R _op ,

8. Loose product.

R ₁ - R _N - voltage divider resistors,

R _op. - reference resistor,

R _see - voltage bias resistor,

K ₁ - K _N - normally closed capacitive sensors,

U _out . - output voltage,

X1 - power connection connector,

X2 - output signal connector,

U1 - voltage regulator,

Р1-Р11 - capacitive sensors.

The device contains a grain bin 1 with a conical bottom, inside of which there are capacitive sensors 2 connected in series with each other with a normally closed output. In this case, some of the sensors 2 are rigidly fixed along one of the walls of the bunker, and others along the bottom. The output of the sensors 2 is connected to the input of the signal processing circuit 3, the output of which is connected to the GPS terminal 4.

The signal processing circuit 3 includes a reference voltage source U _op. 6. connected to the reference resistor R _op. 7 voltage dividers. Each output of the capacitive sensor 2 is connected to the input of the voltage divider resistor R ₁ - R _N , the number of which is selected corresponding to the number of sensors. The outputs of the resistors R ₁ - R _{N of} the voltage divider and the bias voltage resistor R _cm - are connected to the reference resistor 6 R _op 7. The bias voltage resistor R _{cm is} designed to set a voltage different from the reference voltage when all sensors are triggered.

In the claimed device, two types of attachment of capacitive sensors 2 are used, depending on their designs. Cylindrical sensors are mounted on individual brackets on the inner surface of the hopper 1 using screws. Strap-on sensors 2 are attached directly to the inner surface of the hopper 1 with screws. The sensitive surfaces of the sensors face the inner volume of the hopper.

The number of sensors 2 is selected based on the value of the minimum level measurement interval. The lower sensor is installed at the height of the minimum level measurement, the upper sensor is installed at the height of the maximum level measurement.

The device works as follows.

When the grain bunker 1 of the combine is filled with bulk product 8, the capacitive sensors 2 are alternately filled in. At the same time, the contacts in the sensors K ₁ - K _N connected through the resistors R ₁ - R _N to the common "-" alternately open, the voltage across the reference resistor R _op. increases in proportion to the number of sensors filled in with the product in the hopper. Since the circuit is powered from a reference voltage source U _op. , output voltage U _out. does not depend on the supply voltage. Further, an analog signal in the form of an output voltage U _out. transmitted to the GPS terminal 4 and then to the monitoring server (not shown in the drawings). With a decrease in the level of bulk product in the hopper, the reverse process takes place. Contacts in sensors K ₁ - K _N connected through resistors R ₁ - R _N to a common "-" are alternately closed, the voltage across the reference resistor R _op. decreases in proportion to the number of sensors not covered with product in the hopper.

An example of a specific implementation.

11 capacitive sensors (P1-P11) with a normally closed output are attached to the grain bin in series with each other. In this case, some of the sensors are rigidly fixed along one of the walls of the bunker, and others along the bottom. The sensor outputs are connected to the inputs of the signal processing circuit, the output of which is connected to the Locarus-702x GPS terminal.

When filling the grain bunker of the combine with a bulk product, the capacitive sensors are poured alternately. In this case, the contacts in the sensors K ₁ - K ₁₁ connected through the resistors R ₁ - R ₁₁ to the common "-" alternately open, the voltage across the reference resistor R _op. increases in proportion to the number of sensors filled in with the product in the hopper. When all sensors in the bunker fall asleep, the output voltage depends only on the bias resistor R, _see . Since the circuit is powered from a reference voltage source U _op. , output voltage U _out. does not depend on the supply voltage. Further, the analog signal in the form of the output voltage U _out is transmitted to the GPS terminal and then to the monitoring server (not shown in the drawings). With a decrease in the level of bulk product in the hopper, the reverse process takes place. Contacts in sensors K ₁ - K ₁₁ connected through resistors R ₁ - R ₁₁ to a common "-" are alternately closed, the voltage across the reference resistor R _op. decreases in proportion to the number of sensors not covered with product in the hopper.

In the claimed device (Fig. 3) use a voltage stabilizer (U1) brand L7809CV, resistor (R1) MLT-0.25, 1 kOhm, 5%, resistor (R2) MLT-0.25, 1.8 kOhm, 5%, resistor (R3) MLT -0.25, 3.9 kOhm, 5%, resistors (R4 and R12) MLT-0.25, 5.6 kOhm, 5%, resistors (R5 and R6) MLT-0.25, 8.2 kOhm, 5%, resistor (R7) MLT-0.25, 10 kOhm, 5%, resistor (R8) MLT-0.25, 12 kOhm, 5%, resistors (R9, R10, R11) MLT-0.25, 15 kOhm, 5%, resistor (R13) MLT-0.25, 2.7 kOhm, 5% , capacitive sensors (P1-P11) brand CSN E41A5-32N-10-LZ or VBE-Ts18-82V-2123-ZA.

FIG. 3 R13 is R _op. - reference resistor, R12 is R _see - voltage bias resistor.

Locarus-702x connection to analog input A_IN1 is used as GLONASS - GPS terminal.

Table 1 shows the dependence of the voltage level on the level of bulk material in the bin.

The curve shown in FIG. 4 shows the dependence of the change in the grain level in the combine hopper during harvesting. The graph was made using the AgroSignal system, which allows real-time processing of data streams from capacitive sensors installed in the bunker.

A capacitive sensor with a discrete output is a ready-made serial device that responds to changes in electrical capacitance when immersed in bulk material. When triggered, the discrete output of the open collector sensor opens.

Thus, the claimed invention allows on-line measurement of the level of bulk product in the grain bin of the combine with an interval proportional to the number of sensors, the analog signal obtained at the output in the form of voltage is proportional to the level of bulk product in the grain bin of the combine.

Claims (2)

1. A device for discrete measurement of the level of bulk products in a bunker, containing sequentially located level sensors connected to a signal processing circuit, characterized in that capacitive sensors with a normally closed output are used as sensors, the device additionally contains a GPS terminal connected to the output of the processing circuit signal containing a reference voltage source connected to a reference resistor, which is connected to a set of resistive dividers, each of which is connected to the sensor output, while the number of dividers is a multiple of the number of sensors, while some of the sensors are rigidly fixed along one of the walls of the bin, while others along the bottom. 2. The device according to claim 1, characterized in that the capacitive sensors are fixed to the hopper surface by means of screws.

Images