Control device for keeping water level height

Abstract

The utility model discloses a control device for keeping the height of a water level, which comprises an MCU (Microprogrammed Control Unit), a power supply circuit connected with the input end of the MCU, a sampling signal processing circuit, an independent key circuit, a relay driving circuit connected with the output end of the MCU, an EEPROM (Electrically Erasable Programmable Read-Only Memory) circuit mutually connected with the MCU, and a relay module connected with the output end of the relay driving circuit, the output end of the relay module is connected with a water injection pump and a water suction pump. The input end of the sampling signal processing circuit is connected with a water level detection circuit. The water level detection circuit adopting the triode design can directly detect high water level and low water level test points, the sampling signal processing circuit enables the device to start pumping action only when the liquid level is higher than the high water level and stop pumping action only when the liquid level is lower than the low water level, and the device has a certain hysteretic characteristic and can be prevented from continuously switching on and off to work. And the method has a certain anti-interference characteristic.

Description

TECHNICAL FIELD

[0001] The utility model relates to water level detection technical field, especially a kind of control device for keeping water level height. BACKGROUND

[0002] Water level data is closely related to human social life and production, and is needed for planning, design, construction and management of water conservancy projects; water level data is also needed for engineering construction such as bridges, ports, waterways, water supply and drainage; in flood prevention and drought resistance, water level data is even more important, as it is the basis for hydrological forecasting and hydrological information, and is important basic data in the study of water level-flow relationship and the analysis of river sediment and ice conditions. Generally, water level is measured by water gauge and water level gauge, and the observation time and frequency should be adapted to the process of water level change within a day, and should meet the requirements of hydrological forecasting and hydrological information. In general, it is measured 1-2 times a day; when there is flood, ice, flowing ice, ice dam or snowmelt water replenishing the river, the observation frequency is increased, so that the measured results can fully reflect the process of water level change. Water level observation is applicable to underground water level monitoring, river water level monitoring, reservoir water level monitoring, water pool water level monitoring, etc., and can monitor water level dynamic information to provide basis for decision-making.

[0003] With the continuous development of intelligence, water level maintaining device is more important than water level monitoring device. Water level maintaining device will drain or fill water when water level is higher or lower than a certain test point, but most existing water level maintaining devices stop filling water as soon as water level is higher than the test point, and start filling water as soon as water level is lower than the test point, so the water pump is frequently turned on and off, which is too sensitive and easy to cause damage to the equipment, and if the above functions are realized by software, the system software is also prone to crash.

[0004] Therefore, it is urgent to provide a new type of control device for keeping water level height to solve the above problems. CONTENT OF THE UTILITY MODEL

[0005] The technical problem to be solved by the utility model is to provide a control device for keeping water level height, which can effectively avoid the problem of frequent turning on and off of the water pump, and automatically keep the water level at the lower limit position.

[0006] To solve the above technical problems, one technical scheme of the utility model is to provide a control device for keeping water level height, which comprises MCU, power circuit connected with the input end of MCU, sampling signal processing circuit, independent button (time setting) circuit, relay driving circuit connected with the output end of MCU, EEPROM circuit connected with MCU, relay module connected with the output end of relay driving circuit, and water filling pump and water pumping pump connected with the output end of relay module, and the input end of sampling signal processing circuit is connected with water level detection circuit.

[0007] In a preferred embodiment of the utility model, the water level detection circuit is composed of high water level detection circuit and low water level detection circuit, and the high water level detection circuit or the low water level detection circuit comprises PNP triode, resistance R30, R31, R57, capacitor C17, one end of capacitor C17 is connected with the base of PNP triode, the other end is connected with the collector of PNP triode, one end of resistance R57 is connected to the base of PNP triode, one end of resistance R31 is connected to voltage VCC, and the other end is connected to the emitter of PNP triode, one end of resistance R30 is connected to voltage VCC, and the other end is connected to the base of PNP triode, the other end of resistance R57 and the collector of PNP triode respectively lead out a wire as high water level detection site or low water level detection site, and the emitter of PNP triode is used as liquid surface sampling signal output end.

[0008] In a preferred embodiment of the utility model, the sampling signal processing circuit comprises operational amplifier, rear-stage triode, resistance R24~R29 and capacitor C12, resistance R24 and R25 are used as voltage dividing resistance of the same phase input end of operational amplifier, one end of resistance R26 is connected with the same phase input end of operational amplifier, and the other end is connected with the output end of operational amplifier, one end of resistance R27 is connected with the output end of operational amplifier, and the other end is connected with the base of rear-stage triode, resistance R29 is connected between the collector of rear-stage triode and voltage VCC, capacitor C12 and resistance R28 are connected in parallel between the base and the emitter of rear-stage triode, capacitor C12 and resistance R27 form RC filter circuit, and the liquid surface sampling signal collected by the water level detection circuit is input to the inverse phase input end of operational amplifier.

[0009] In a preferred embodiment of the utility model, the EEPROM adopts chip AT24C02, carries out data transmission with MCU through IIC protocol, and is mainly used for storing time data.

[0010] In a preferred embodiment of the utility model, the independent key circuit is provided with three keys of addition, subtraction and confirmation, and is used for setting time data in EEPROM.

[0011] In a preferred embodiment of the utility model, the output end of the MCU is further connected with digital tube driving and display circuit, adopts common anode digital tube of four-in-one, carries out digital tube bit selection through NPN triode, and displays the set time.

[0012] In a preferred embodiment of the utility model, the relay driving circuit comprises level conversion chip IC4, the relay module comprises relays K1-K4 and corresponding LED lamps, the level conversion chip IC4 uses the 5V signal output by MCU to control the relay of 12V, realizes the function of level conversion, and the high and low level output by MCU controls the attraction and disconnection of relays K1-K4.

[0013] Further, the level conversion chip IC4 adopts ULN2003.

[0014] In a preferred embodiment of the utility model, the peripheral circuit of the MCU further includes a working state indicating circuit and a working abnormality alarm circuit for indicating and alarming the working state of the MCU.

[0015] In a preferred embodiment of the utility model, the peripheral circuit of the MCU further includes a working state indicating circuit and a working abnormality alarm circuit for indicating and alarming the working state of the MCU.

[0016] The utility model has the advantages of:

[0017] (1) the water level detection circuit adopting the triode design of the utility model can directly detect high water level and low water level test points, the sampling signal processing circuit makes the device start pumping only when the liquid level is higher than the high water level, and stop pumping only when the liquid level is lower than the low water level, the device has certain hysteresis characteristics, can avoid the device constantly switching on and off, and has certain anti-interference characteristics.

[0018] (2) the utility model has simple circuit structure and low cost, can automatically keep the water level at the lower limit position, and can be widely applied in the field of intelligent agriculture, including pond culture and intelligent irrigation. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 It is the structure block diagram of the preferred embodiment of the water level height maintaining control device;

[0020] Figure 2 It is the structure schematic diagram of the preferred embodiment of the water level height maintaining control device;

[0021] Figure 3 It is the water level detection circuit principle diagram;

[0022] Figure 4 It is the sampling signal processing circuit principle diagram;

[0023] Figure 5 It is the EEPROM circuit principle diagram;

[0024] Figure 6 It is the independent button circuit principle diagram;

[0025] Figure 7 It is the nixie tube drive and display circuit principle diagram;

[0026] Figure 8is the power supply circuit schematic diagram of the application;

[0027] Figure 9 is the relay drive circuit schematic diagram of the application;

[0028] Figure 10 is the MCU circuit schematic diagram of the application;

[0029] Figure 11 is the crystal oscillator circuit schematic diagram of the application;

[0030] Figure 12 is the reset circuit schematic diagram of the application;

[0031] Figure 13 is the serial port burning circuit schematic diagram of the application;

[0032] Figure 14 is the working abnormality alarm circuit schematic diagram of the application;

[0033] Figure 15 is the working state indication circuit schematic diagram of the application.

[0034] The labels of the components in the drawings are as follows: 1, container, 2, liquid level, 3, low water level sensor lead, 4, high water level sensor lead. DETAILED DESCRIPTION

[0035] The preferred embodiments of the present application are described in detail below with reference to the drawings, so that the advantages and features of the present application can be more easily understood by those skilled in the art, and the protection scope of the present application is more clearly defined.

[0036] Please refer to Figure 1 and Figure 2 The embodiments of the present application include:

[0037] A control device for maintaining water level height, comprising an MCU, a power supply circuit connected to the input end of the MCU, a sampling signal processing circuit, an independent button (time setting) circuit, a relay drive circuit connected to the output end of the MCU, an EEPROM circuit connected to the MCU, a relay module connected to the output end of the relay drive circuit, a water injection pump and a water pump connected to the output end of the relay module, and a water level detection circuit connected to the input end of the sampling signal processing circuit.

[0038] In combination with Figure 3The water level detection circuit is composed of high water level detection circuit and low water level detection circuit, and each circuit component and its connection relationship are shown in the figure. The high water level detection circuit and the low water level detection circuit have the same circuit. The high water level detection circuit or the low water level detection circuit comprises a PNP triode, resistors R30, R31 and R57, and a capacitor C17. One end of the capacitor C17 is connected to the base of the PNP triode, and the other end is connected to the collector of the PNP triode. One end of the resistor R57 is connected to the base of the PNP triode. One end of the resistor R31 is connected to the voltage VCC, and the other end is connected to the emitter of the PNP triode. One end of the resistor R30 is connected to the voltage VCC, and the other end is connected to the base of the PNP triode. The other end of the resistor R57 and the collector of the PNP triode are respectively led out with a wire, and the two wires form a group as a high water level detection site or a low water level detection site. The emitter of the PNP triode serves as a liquid surface sampling signal output end. When the liquid surface submerges the two wires at the same time, the PNP triode is turned on due to the conductive property of the liquid, so that the emitter potential (AD1) is lowered. The extent of the lowering of the emitter potential (AD1) needs to be further processed by the sampling signal processing circuit. Figure 2 The low water level sensor lead 3 is arranged at the low position of the container 1, and the high water level sensor lead 4 is arranged at the high position of the container 1. They can also be sequentially fixed on a wooden stick, and the wooden stick is placed in the liquid surface 2. The distance between the high and low water level detection points can be adjusted according to the needs. When the low point contacts the liquid surface 2, the MCU detects the low water level signal through external interruption. Preferably, the model of the PNP triode is 2SA1037AK.

[0039] In combination with Figure 4, the sampling signal processing circuit comprises an operational amplifier, a later-stage transistor N2, resistors R24-R29, and a capacitor C12, the resistors R24 and R25 are voltage dividing resistors of the non-inverting input terminal of the operational amplifier, one end of the resistor R26 is connected to the non-inverting input terminal of the operational amplifier, the other end is connected to the output terminal of the operational amplifier, one end of the resistor R27 is connected to the output terminal of the operational amplifier, the other end is connected to the base of the later-stage transistor, the resistor R29 is connected between the collector of the later-stage transistor and the voltage VCC, the capacitor C12 is connected in parallel with the resistor R28 between the base and the emitter of the later-stage transistor, the capacitor C12 and the resistor R27 form an RC filter circuit, and the circuit components and the connection relationship thereof are shown in the figure. The liquid level sampling signal AD1 collected by the water level detection circuit is input to the inverting input terminal of the operational amplifier, and the potential set by the voltage dividing resistors R24 and R25 at the non-inverting input terminal is compared through the operational amplifier. When the potential at the inverting terminal is lower than that at the non-inverting terminal, the operational amplifier outputs a high level, turns on the later-stage transistor N2, and the later-stage transistor N2 is turned on, the collector potential is pulled low and triggers the external low-level interrupt of the MCU. The operational amplifier is used as a comparator, and the hysteresis comparator connection method has a certain anti-interference property, reduces the sensitivity of the device, and prevents multiple false triggers near the threshold. Preferably, the model of the operational amplifier is TLV2772Q, and the model of the later-stage transistor N2 is 2SC2412K.

[0040] In combination Figure 5 , the circuit components of the EEPROM circuit and the connection relationship thereof are shown in the figure, and the EEPROM circuit comprises a chip IC5, resistors R36-R41, and a capacitor C13. The EEPROM adopts a chip AT24C02, performs data transmission with the MCU through an IIC protocol, and is mainly used for storing time data. The time data is an upper limit of the time during which the low water level detection circuit does not detect the liquid level signal. If the time exceeds the upper limit, the MCU will start the water injection function, and the water injection will be stopped until the low water level signal is detected, so as to ensure that the water level is maintained at the low water level.

[0041] In combination Figure 6 , the independent button circuit is provided with three buttons of add, subtract, and confirm, which are used for setting the time data in the EEPROM. The MCU pin is in a default high level, and is pulled low after the button is pressed. The software detects the button pressing, sets the time through the add and subtract buttons, and stores the data in the EEPROM after the confirm button is pressed.

[0042] Further, the output end of the MCU is further connected to a digital tube driving and display circuit, which is shown in Figure 7The circuit elements of the digital tube driving and display circuit and the connection relationship thereof are shown in the figure. A common anode digital tube with four units in one is adopted, the digital tube bit selection is performed through an NPN transistor, and the MCU outputs display data; independent buttons are used to set time and the time is directly displayed through the digital tube, and the digital tube displays the set time after the time data is set. Preferably, the model of the NPN transistor is 2SC2412K.

[0043] In combination Figure 8 The circuit elements of the power supply circuit and the connection relationship thereof are shown in the figure. Since the control system uses a 12V relay to control the water pump and the water injection pump to access the circuit, and the MCU needs a 5V power supply, a LM2596 chip is used to perform buck voltage reduction to realize 12V input and 5V output, and the output 5V voltage is given to the single-chip microcomputer system.

[0044] In combination Figure 9 The relay driving circuit includes a level conversion chip IC4, and the relay module includes relays K1-K4 and corresponding LED lamps, and the circuit elements and the connection relationship thereof are shown in the figure. The level conversion chip IC4 uses the 5V voltage signal output by the MCU to control the 12V relay to realize the level conversion function, and the high and low level output by the MCU controls the attraction and disconnection of the relays K1-K4. Specifically, when the MCU outputs 5V high level, the ULN2003 outputs low level 0V, and the upper end of the relay is 12V voltage, so the voltage between the two ends of the relay is 12V, the relay is powered to attract, at this time, the relay connects the external household electricity 220V and the water pump to the electric appliance. When the MCU outputs 0V low level, the ULN2003 outputs high level 12V, the voltage between the two ends of the relay is 0V, the relay cannot be attracted and is in a disconnected state, the water pump and the 220V power supply are disconnected and stop working. Preferably, the level conversion chip IC4 adopts ULN2003.

[0045] The peripheral circuit of the MCU includes a crystal oscillator circuit, a reset circuit, a serial port burning circuit, a working state indication circuit and a working abnormality alarm circuit, which ensures that the MCU can normally run the program. In the example, the model of the MCU used is STC89C52RC, as shown in Figure 10 In combination Figure 11 The crystal oscillator circuit generates a working clock for the MCU. In combination Figure 12 The reset circuit ensures that the MCU program can be reset and start running again when the program runs away; the MCU used in the device is a high-level reset, when S2 is pressed, RST is directly pulled high by the 5V power supply, and the MCU receives the RST pull-up signal to start running the program again. In combination Figure 13The serial programming circuit is connected with the MCU and the PC through the USB-to-serial CH340T chip, and the MCU and the PC transmit data through the chip to program the program file compiled by the user into the MCU. Figure 14 The working state indicating circuit and the working abnormality alarm circuit are used for indicating and alarming the working state of the MCU. Figure 15 When the MCU works normally, the light-emitting diode LED3 flashes at a frequency set by the timer, and when the state of LED3 is abnormal, the abnormal program running can be found.

[0046] The working principle of the device is as follows: the MCU confirms whether the liquid level reaches the specified position through the sampling signal of the high / low water level detection circuit, controls the relay to be attracted to control the water injection pump and the water pumping pump to work. The time length that the low water level detection circuit cannot detect the water level can be set through the independent button, stored in the EEPROM chip through the IIC, and displayed through the numeral tube. When the water level in the container rises due to rain and the like, the water pumping pump does not work when the MCU detects the water level signal of the low water level detection circuit, and the water pumping pump starts to work only when the high water level detection circuit detects the water level signal.

[0047] The above-mentioned embodiments are merely examples of the present application, and do not limit the patent range of the present application, and any equivalent structure or equivalent process conversion, or direct or indirect application in other related technical fields, are also included in the patent protection range of the present application.

Claims

1. A control device for maintaining water level, characterized in that, It includes an MCU, a power supply circuit connected to the input terminal of the MCU, a sampling signal processing circuit, an independent button circuit, a relay drive circuit connected to the output terminal of the MCU, an EEPROM circuit interconnected with the MCU, a relay module connected to the output terminal of the relay drive circuit, the output terminal of the relay module is connected to a water injection pump and a water pump, and the input terminal of the sampling signal processing circuit is connected to a water level detection circuit.

2. The control device for maintaining water level height according to claim 1, characterized in that, The water level detection circuit consists of a high water level detection circuit and a low water level detection circuit. The high water level detection circuit or the low water level detection circuit includes a PNP transistor, resistors R30, R31, R57, and capacitor C17. One end of capacitor C17 is connected to the base of the PNP transistor and the other end is connected to the collector of the PNP transistor. One end of resistor R57 is connected to the base of the PNP transistor. One end of resistor R31 is connected to voltage VCC and the other end is connected to the emitter of the PNP transistor. One end of resistor R30 is connected to voltage VCC and the other end is connected to the base of the PNP transistor. The other end of resistor R57 and the collector of the PNP transistor are each connected to a wire as a high water level detection point or a low water level detection point. The emitter of the PNP transistor serves as the output terminal for the liquid level sampling signal.

3. The control device for maintaining water level height according to claim 1, characterized in that, The sampling signal processing circuit includes an operational amplifier, a subsequent transistor, resistors R24 to R29, and capacitor C12. Resistors R24 and R25 serve as voltage divider resistors for the non-inverting input of the operational amplifier. One end of resistor R26 is connected to the non-inverting input of the operational amplifier, and the other end is connected to the output of the operational amplifier. One end of resistor R27 is connected to the output of the operational amplifier, and the other end is connected to the base of the subsequent transistor. Resistor R29 is connected between the collector of the subsequent transistor and the voltage VCC. Capacitor C12 and resistor R28 are connected in parallel between the base and emitter of the subsequent transistor. Capacitor C12 and resistor R27 form an RC filter circuit. The liquid level sampling signal collected by the water level detection circuit is input to the inverting input of the operational amplifier.

4. The control device for maintaining water level height according to claim 1, characterized in that, The EEPROM uses the AT24C02 chip and transmits data with the MCU via the IIC protocol. It is mainly used to store time data.

5. The control device for maintaining water level height according to claim 1, characterized in that, The independent button circuit has three buttons: plus, minus, and confirm, which are used to set the time data in the EEPROM.

6. The control device for maintaining water level height according to claim 1, characterized in that, The output of the MCU is also connected to a digital tube driver and display circuit, which uses a four-in-one common anode digital tube and selects the digital tube digits through an NPN transistor to display the set time.

7. The control device for maintaining water level height according to claim 1, characterized in that, The relay driving circuit includes a level conversion chip IC4, and the relay module includes relays K1-K4 and corresponding LEDs. The level conversion chip IC4 uses the 5V signal output by the MCU to control the 12V relays, realizing the level conversion function. The high and low levels output by the MCU control the activation and deactivation of relays K1-K4.

8. The control device for maintaining water level height according to claim 7, characterized in that, The level conversion chip IC4 is ULN2003.

9. The control device for maintaining water level height according to claim 1, characterized in that, The peripheral circuits of the MCU include a crystal oscillator circuit, a reset circuit, and a serial port programming circuit. The crystal oscillator circuit generates the working clock for the MCU; the reset circuit is used to reset the MCU and restart the program; and the serial port programming circuit programs the user-compiled program file into the MCU.

10. The control device for maintaining water level height according to claim 1, characterized in that, The peripheral circuits of the MCU also include a working status indication circuit and a working abnormality alarm circuit, which are used to indicate and alarm the working status of the MCU.

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