CN102410868B - Batching controller and ingredient control method thereof - Google Patents

Abstract

The invention discloses a batching controller and a batching control method thereof. The batching controller includes a sensor input terminal, a filter circuit for eliminating interference signals, an amplifying circuit, a built-in temperature measuring module, and can monitor the temperature of the batching controller according to the external temperature. Compensated MCU, display drive circuit, optocoupler and drive circuit, keyboard circuit, etc. Due to the temperature compensation and anti-interference filtering processing, the batching controller reduces its sensitivity to external temperature changes, and its anti-interference ability is also improved, thereby improving the stability and reliability of the entire batching controller as a whole.

Description

Batching controller and batching control method thereof

technical field

The invention relates to a weighing meter, in particular to a batching controller and a batching control method thereof.

Background technique

In industrial production processes such as food processing, tobacco processing, chemical product processing, feed processing, etc., the batching of some bulk materials needs to be weighed and measured for batching control. The current batching system generally includes a material hopper, which is provided with several feeding ports for feeding different materials. The feeding port of each material is provided with a coarse feeding port and a fine nozzle, and a weight sensor is provided under the material hopper. Includes ingredient controller for material release control. When in use, connect the batching controller with the weight sensor and the control valve of the feeding port of each material, and set the total feeding amount of each material (assuming there are three kinds of materials) in the batching and the rough feeding of each material through the batching controller. Threshold value and the feeding order of all materials, and then simultaneously start the coarse feeding port and the fine feeding port of the first material for feeding, and then the batching controller judges whether the instantaneous weight signal returned by the weight sensor reaches the rough feeding of the first material. If it reaches the threshold, close its coarse nozzle, and then judge whether the instantaneous weight signal returned by the weight sensor reaches the total amount of the first material, if it reaches, close its fine nozzle, so as to complete the first material. Putting in, and so on, according to the order of putting in the second material and the third material, after that, the batching controller sends a discharge signal to the material hopper to make it unload the material automatically, thus completing a material batching process. The Chinese patent that the patent No. is 03143256.5 also discloses a kind of continuous automatic batching machine and batching control method thereof, and it is the bulk material automatic control system formed by PLC plus stepper motor. However, the continuous automatic batching machine is sensitive to external temperature and has poor anti-interference ability.

Contents of the invention

The object of the present invention is to provide a batching controller with stable and reliable performance and a batching control method thereof.

To achieve the above object, the present invention provides a batching controller on the one hand, comprising:

The sensor input terminal is used to receive the instantaneous weight signal output by the weight sensor;

A filter circuit, used to filter out the high-frequency interference in the instantaneous weight signal;

an amplification circuit, used to amplify the instantaneous weight signal processed by the filter circuit;

MCU, which pre-stores the total amount of each material in the batching, the rough input threshold of each material, and the input sequence of all materials, and is used to obtain the instantaneous weight signal and the built-in temperature measurement module of the MCU during the input process. For the current external temperature signal output, the instantaneous weight signal and the external temperature signal are converted into corresponding digital signals according to the built-in AD conversion module. After performing sliding average filtering on the digitized instantaneous weight signal, according to the digitized The external temperature signal performs temperature compensation on the instantaneous weight signal after sliding average filtering, accumulates and calculates the instantaneous weight signal after temperature compensation, and based on the current accumulated weight, the rough input threshold of the corresponding material, the total input amount of the corresponding material, and the input sequence carry out delivery control;

A display drive circuit, used to send the accumulated weight calculated by the MCU to the digital tube display in real time;

An optocoupler and a drive circuit, used for anti-interference isolation of the control signal output by the MCU and then driving the output;

The keyboard circuit is used to set the instrument parameters, and the instrument parameters include the total amount of each material in the batching, the rough input threshold of each material, and the input sequence of all materials.

In the batching controller of the present invention, the temperature compensation is carried out on the instantaneous weight signal after sliding average filtering according to the digitized external temperature signal, which specifically includes:

According to the formula y=y-k*Δt, temperature compensation is performed on the instantaneous weight signal after moving average filtering, wherein, y is the instantaneous weight, k is the temperature compensation coefficient, and Δt is the current time.

Batching controller of the present invention also includes:

The RS232 communication module and the RS485 communication module used for the communication between the MCU and the upper computer, and the communication switching circuit used for mode switching between the RS232 communication module and the RS485 communication module, the communication switching circuit is respectively connected to the One end of the RS232 communication module is connected with one end of the RS485 communication module, and is connected with the MCU through a serial port.

Batching controller of the present invention also includes:

A protection circuit for performing anti-interference processing on the input or output signal of the RS485 communication module or the RS485 communication module, the protection circuit is connected to the other end of the RS232 communication module and the other end of the RS485 communication module respectively connected.

Batching controller of the present invention also includes:

A terminal block, on which the optocoupler, the drive circuit, and the input or output terminal of the protection circuit are integrated.

In yet another aspect, the present invention also provides a batching control method of the above batching controller comprising the following steps:

Simultaneously open the coarse throw and the fine throw of the first material in the batching to carry out the dropping of the first kind of material;

Obtain the instantaneous weight signal output by the weight sensor and the current external temperature signal output by the built-in temperature measurement module of the MCU during the delivery process;

Convert the instantaneous weight signal and the external temperature signal into corresponding digital signals according to the built-in AD conversion module;

After performing sliding average filtering on the digitized instantaneous weight signal, temperature compensation is performed on the sliding average filtered instantaneous weight signal according to the digitized external temperature signal;

Accumulating the instantaneous weight signal after temperature compensation, and judging whether the current accumulated weight reaches the rough feeding threshold of the first material, and if so, closing the rough feeding port of the first material;

Judging whether the current accumulative weight has reached the total amount of the first material, if so, closing the fine feeding port of the first material;

According to the delivery sequence and in accordance with the above-mentioned method, the delivery of other materials in the ingredients to be prepared is performed.

In the batching control method of the present invention, the temperature compensation is carried out on the instantaneous weight signal after the sliding average filtering according to the digitized external temperature signal, which specifically includes:

According to the formula y=y-k*Δt, temperature compensation is performed on the instantaneous weight signal after moving average filtering, wherein, y is the instantaneous weight, k is the temperature compensation coefficient, and Δt is the current time.

In the batching control method of the present invention, the batching controller also includes:

The RS232 communication module and the RS485 communication module used for the communication between the MCU and the upper computer, and the communication switching circuit used for mode switching between the RS232 communication module and the RS485 communication module, the communication switching circuit is respectively connected to the One end of the RS232 communication module is connected with one end of the RS485 communication module, and is connected with the MCU through a serial port.

In the batching control method of the present invention, the batching controller also includes:

A protection circuit for performing anti-interference processing on the input or output signal of the RS485 communication module or the RS485 communication module, the protection circuit is connected to the other end of the RS232 communication module and the other end of the RS485 communication module respectively connected.

In the batching control method of the present invention, the batching controller also includes:

A terminal block, on which the optocoupler, the drive circuit, and the input or output terminal of the protection circuit are integrated.

The batching controller of the present invention includes a filter circuit for filtering out the high-frequency interference in the instantaneous weight signal output by the weight sensor, and the total dosage of each material in the batching, the rough throwing threshold of each material, and the MCU are pre-stored in the MCU. And the delivery sequence of all materials. During the delivery process, the MCU obtains the instantaneous weight signal and the current external temperature signal output by the built-in temperature measurement module of the MCU, and converts the instantaneous weight signal and the external temperature signal into corresponding digital signals according to the built-in AD conversion module. , after performing sliding average filtering on the digitized instantaneous weight signal, temperature compensation is performed on the instantaneous weight signal after the sliding average filtering according to the digitized external temperature signal, and the instantaneous weight signal after temperature compensation is accumulated and calculated, and according to the current The accumulative weight, the rough input threshold of the corresponding materials, the total input amount of the corresponding materials and the input sequence are used for input control. Therefore, the batching controller of the present invention reduces its sensitivity to external temperature changes, and its anti-interference ability has also been improved. , thereby improving the stability and reliability of the entire batching controller as a whole.

Description of drawings

Fig. 1 is the circuit block diagram of the batching controller of an embodiment of the present invention;

Fig. 2 is the schematic circuit diagram of the MCU part of the batching controller in Fig. 1;

Fig. 3 is the circuit schematic diagram of the sensor connection terminal and filter circuit part of the batching controller in Fig. 1;

Fig. 4 is the schematic circuit diagram of the amplifying circuit part of the batching controller in Fig. 1;

Fig. 5 is the schematic circuit diagram of the keyboard circuit part of the batching controller in Fig. 1;

Fig. 6 is the schematic circuit diagram of the display drive circuit part of the batching controller in Fig. 1;

Fig. 7 is the schematic circuit diagram of the communication switching circuit and the protection circuit part of the batching controller in Fig. 1;

Fig. 8 is the schematic circuit diagram of the RS485 communication module and the RS232 communication module part of the batching controller in Fig. 1;

Fig. 9 is a circuit schematic diagram of the optocoupler and the drive circuit part of the batching controller in Fig. 1;

Fig. 10 is a schematic diagram of the interface structure of the terminal block of the batching controller in Fig. 1;

Fig. 11 is a schematic circuit diagram of the power circuit part of the batching controller in Fig. 1 .

detailed description

The specific embodiment of the present invention is described in detail below in conjunction with accompanying drawing:

Referring to Fig. 1, the batching controller of this embodiment includes sensor input terminals, filter circuit, amplifier circuit, MCU, display drive circuit, optocoupler and drive circuit, keyboard circuit, RS232 communication module, RS485 communication module, communication switching circuit , protection circuit, terminal block and power circuit, etc. Wherein, the sensor input terminal is used to receive the instantaneous weight signal output by the weight sensor. The filter circuit is used to filter out the high-frequency interference in the instantaneous weight signal. The amplifying circuit is used to amplify the instantaneous weight signal processed by the filter circuit. The MCU pre-stores the total delivery amount of each material in the batching, the rough input threshold of each material, and the delivery sequence of all materials, which are used to obtain the instantaneous weight signal and the current external temperature output by the built-in temperature measurement module of the MCU during the delivery process. Signal, according to the built-in AD conversion module, the instantaneous weight signal and the external temperature signal are converted into corresponding digital signals. The instantaneous weight signal is temperature compensated, and the instantaneous weight signal after temperature compensation is accumulated and calculated, and the feeding control is performed according to the current accumulated weight, the rough feeding threshold of the corresponding material, the total feeding amount of the corresponding material, and the feeding sequence. The display driving circuit is used to send the accumulated weight calculated by the MCU to the digital tube display in real time. The optocoupler and the drive circuit are used to isolate the control signal output by the MCU for anti-interference and then drive the output. The keyboard circuit is used to set the parameters of the instrument, such as the total input amount of each material in the batching, the rough input threshold of each material, and the input sequence of all materials, etc. And the power circuit is used to supply power to the device.

As shown in Figure 2, the MCU can choose the single-chip microcomputer model AduC847 and its peripheral circuit, and its peripheral circuit includes a driver chip model 74HC245D connected to it.

As shown in FIG. 3 , the second and third terminals of the sensor input terminal are connected to the input end of the filter circuit. The sixth terminal of the sensor input terminal is connected to the ST terminal of the filter circuit. The SN- terminal and SN+ terminal of the filter circuit are respectively connected to the 7th and 8th pins of the above-mentioned single-chip microcomputer.

As shown in Figure 4, the amplifier circuit can choose the AD8552 amplifier chip and its peripheral circuits, wherein the third and fifth pins of the amplifier chip are respectively connected to the +INA and +INB output terminals of the filter circuit. The SIG+ and SIG- terminals of the amplifying circuit are respectively connected to the 9th and 10th pins of the above-mentioned single chip microcomputer.

As shown in FIG. 5 , the four keys SW1 , SW2 , SW3 and SW4 of the keyboard circuit are respectively connected to the 52nd to 49th pins of the above-mentioned single-chip microcomputer.

As shown in Figure 6, the display drive circuit can choose two integrated serial input/output common-cathode display drivers U2 and U3 whose model is Max7219, and the 1st, 13th and 12th pins of the display driver U2 correspond to the The 22nd, 23rd and 24th pins of the above-mentioned single-chip microcomputer are connected. The 1st, 13th and 12th pins of the display driver U3 are respectively connected to the 22nd, 23rd and 25th pins of the single-chip microcomputer.

As shown in Figure 8, the RS232 communication module includes a MAX232 chip and its peripheral circuits, and the RS485 communication module includes a MAX485 chip and its peripheral circuits, wherein the 11th pin of the MAX232 chip and the 4th pin of the MAX485 chip are respectively Correspondingly connected to the two selection terminals of the selection switch SW7, the common terminal of the selection switch SW7 is connected to the 17th pin of the above-mentioned single chip microcomputer. The 12th pin of the MAX232 chip and the 1st pin of the MAX485 chip are respectively connected to the two selection terminals of the selection switch SW8 correspondingly, and the common terminal of the selection switch SW8 is connected to the 16th pin of the above-mentioned single-chip microcomputer.

As shown in Figure 7, between the selection switch SW5 and the resistor L1, and between the selection switch SW6 and the resistor L2, there is a protection circuit composed of a TVS diode and a capacitor connected in parallel to protect the communication chip and MCU from external bursts. Interference damage. Among them, the two selection terminals of the selection switch SW5 are respectively connected to the JL+ terminal of the RS485 communication module and the 14th pin of the MAX232 chip, and the two selection terminals of the selection switch SW6 are respectively corresponding to the JL- terminal of the RS485 communication module and the MAX232 chip The 13th pin is connected.

As shown in Figure 9, the optocoupler and its drive circuit include two optocoupler chips U7a and U7b of the model TLP521-4 and their peripheral circuits, as well as two Darlington tubes U12a and Darlington tubes of the model ULN2003 U12b and its peripheral circuits. Among them, the 2nd, 4th, 6th, and 8th pins of the optocoupler chip U7a are respectively connected to the 11th, 18th, 17th, and 16th pins of the driver chip whose model is 74HC245D. The 13th, 11th, 9th and 15th pins of U7a are respectively connected to the first to third pins of the Darlington tube U12a and the first pin of the Darlington tube U12b. The 2nd, 4th, 6th and 8th pins of the optocoupler chip U7b are respectively connected to the 15th, 14th, 13th and 12th pins of the driver chip whose model is 74HC245D. The 15th, 13th, 11th and 9th pins are respectively connected to the 4th to 7th pins of the Darlington tube U12a.

As shown in Figure 10, POW, OUT1, OUT2, OUT3, OUT4, OUT5, OUT6, OUT7, OUT8, and COM1 of the terminal block are reserved ports for the output interface to connect to the external 24V power supply and the function control relay coil. TXD, RXD and SG are 485 and 232 communication interfaces. EA, SIG-, SIG+, E-, E+ are sensor line interfaces. ST and COM2 are 1-way I/O input signal interface, used to start the batching controller. L, PE and L are AC220V power ports.

As shown in Figure 11, the power circuit is mainly composed of filters, transformers, bridge rectifier circuits, filter circuits and several voltage regulator circuits, so as to provide +12V, +5V and other required power for the batching controller.

The working process of the above batching controller is as follows:

1) Start the batching process after setting the parameters.

2) Simultaneously open the coarse and fine inlets of the first material in the batching to put in the first material.

3) Obtain the instantaneous weight signal output by the weight sensor and the current external temperature signal output by the built-in temperature measurement module of the MCU during the delivery process.

4) Convert the instantaneous weight signal and external temperature signal into corresponding digital signals according to the built-in AD conversion module.

5) After performing sliding average filtering on the digitized instantaneous weight signal, temperature compensation is performed on the sliding average filtered instantaneous weight signal according to the digitized external temperature signal. Specifically, temperature compensation can be performed on the instantaneous weight signal after sliding average filtering according to the formula y=y-k*Δt, wherein y is the instantaneous weight, k is the temperature compensation coefficient (obtainable according to a large number of experiments), and Δt is the current time.

6) Accumulate the instantaneous weight signal after temperature compensation, and judge whether the current accumulated weight reaches the rough feeding threshold of the first material, and if so, close the rough feeding port of the first material.

7) Judging whether the current cumulative weight reaches the total feeding amount of the first material, if so, close the fine feeding port of the first material.

8) According to the order of delivery and in accordance with the above method, the delivery of other materials in the ingredients to be prepared is carried out.

9) Output the unloading signal to the material hopper to make it unload and complete a batching process.

The batching controller of the present invention is especially suitable for the batching control process of concrete mixing and asphalt mixing equipment, and is also suitable for occasions requiring batching control such as converters, chemical industry, and feed.

The above embodiment is only a description of the preferred implementation of the present invention, and is not intended to limit the scope of the present invention. On the premise of not departing from the design spirit of the present invention, ordinary engineers and technicians in the field can make various modifications to the technical solution of the present invention. and improvements, all should fall within the scope of protection determined by the claims of the present invention.

Claims (10)

1. a batching controller, it is characterised in that include:

Sensor input, for receiving the instantaneous weight signal of weight sensor output；

Filter circuit, for filtering the High-frequency Interference in described instantaneous weight signal；

Amplifying circuit, is amplified for the instantaneous weight signal after processing described filter circuit；

MCU, prestoring needs total injected volume of every kind of material in dispensing, the thick of every kind of material and throws threshold value, Yi Jisuo There is the release sequence of material, be used in launch process, obtain described instantaneous weight signal and described MCU is built-in Temperature measurement module output current outside temperature signal, according to built-in AD conversion module by described instantaneous weight Signal and described ambient temperature signal are transformed into corresponding data signal, the instantaneous weight letter after to digitlization After number carrying out moving average filter, according to the ambient temperature signal after digitlization to the wink after moving average filter When weight signal carry out temperature-compensating, accumulation calculating, and root are carried out to the instantaneous weight signal after temperature-compensating Carry out according to thick threshold value, total injected volume of corresponding material and the release sequence of throwing of current accumulator weight, corresponding material Throw in control；

Display driver circuit, shows to charactron for the accumulator weight transmission calculating described MCU in real time Show；

Optocoupler and drive circuit, for carrying out anti-interference isolation rear drive by the control signal of described MCU output Output；

Keyboard circuit, is used for arranging meter parameter, and described meter parameter includes treating the total of every kind of material in dispensing Injected volume, the thick release sequence throwing threshold value and all materials of every kind of material.

2. batching controller according to claim 1, it is characterised in that described according to digitlization after Ambient temperature signal carries out temperature-compensating to the instantaneous weight signal after moving average filter, specifically includes:

According to formula y=y-k* Δ t, temperature-compensating is carried out to the instantaneous weight signal after moving average filter, its In, y is instantaneous weight, and k is temperature compensation coefficient, Δ t current time.

3. batching controller according to claim 2, it is characterised in that also include:

It for RS232 communication module and the RS485 communication module of described MCU and upper machine communication, and is used for The communication switching circuit of the inter mode switching of described RS232 communication module and described RS485 communication module, described The communication switching circuit one end phase with one end of described RS232 communication module and described RS485 communication module respectively Even, it and is connected with described MCU by serial ports.

4. batching controller according to claim 3, it is characterised in that also include:

Protection circuit, for carrying out anti-interference place to the signal inputting or exporting described RS485 communication module Reason, described protection circuit respectively with the other end of described RS232 communication module and described RS485 communication module The other end is connected.

5. batching controller according to claim 4, it is characterised in that also include:

Terminal block, it is integrated with described optocoupler and drive circuit, the input of described protection circuit or output Son.

6. the ingredient control method of batching controller described in a claim 1, it is characterised in that include with Lower step:

Open simultaneously and treat that in dispensing, the thick of the first material is thrown mouth and carefully throw the throwing that mouth carries out the first material described Put；

The instantaneous weight signal of weight sensor output and the thermometric that described MCU is built-in is obtained in launch process The current outside temperature signal of module output；

It is right to be transformed into described instantaneous weight signal and described ambient temperature signal according to built-in AD conversion module The data signal answered；

After instantaneous weight signal after to digitlization carries out moving average filter, according to the external world after digitlization Temperature signal carries out temperature-compensating to the instantaneous weight signal after moving average filter；

Accumulation calculating is carried out to the instantaneous weight signal after temperature-compensating, and judges whether current accumulator weight reaches Thick to the first material described throws threshold value, if reached, then closes the thick of the first material described and throws mouth；

Judging whether current accumulator weight reaches total injected volume of the first material described, if reached, then closing Close the thin of the first material described and throw mouth；

According to release sequence and according to aforesaid way carry out described in treat the input of unclassified stores in dispensing.

7. ingredient control method according to claim 6, it is characterised in that described according to digitlization after Ambient temperature signal temperature-compensating is carried out to the instantaneous weight signal after moving average filter, specifically include:

According to formula y=y-k* Δ t, temperature-compensating is carried out to the instantaneous weight signal after moving average filter, its In, y is instantaneous weight, and k is temperature compensation coefficient, Δ t current time.

8. ingredient control method according to claim 6, it is characterised in that described batching controller is also Including:

RS232 communication module and RS485 communication module, Yi Jiyong for described MCU and upper machine communication In the communication switching circuit of the inter mode switching of described RS232 communication module and described RS485 communication module, institute State communication switching circuit one end with one end of described RS232 communication module and described RS485 communication module respectively It is connected, and be connected with described MCU by serial ports.

9. ingredient control method according to claim 8, it is characterised in that described batching controller is also Including:

Protection circuit, for carrying out anti-interference place to the signal inputting or exporting described RS485 communication module Reason, described protection circuit respectively with the other end of described RS232 communication module and described RS485 communication module The other end is connected.

10. ingredient control method according to claim 9, it is characterised in that described batching controller is also Including:

Terminal block, it is integrated with described optocoupler and drive circuit, the input of described protection circuit or output Son.