SU1017230A1 - Device for automatic control of watering - Google Patents

Description

The invention relates to agriculture, namely, irrigated agriculture, and can be used to automatically control the irrigation actuators in open and closed ground.

A device for automatic irrigation control is known, comprising a soil moisture meter, a comparison unit with a pre-irrigation value setter, an irrigation unit and program control. In addition, the device is equipped with a block-automatic calibration of a moisture meter connected to the output and input of a moisture meter and to the output of a software control unit.

However, this device is characterized by a low measurement accuracy, since watering is carried out on the basis of measuring the moisture content of the soil, the optimum value of which varies for different types of soil, weathering conditions, etc.

It is also known a device for automatic irrigation control, including irrigation sensors, comparison units, logic control unit, time relay and irrigation unit, as well as a measurement synchronization unit whose outputs are connected to irrigation sensors and comparison and logic control units 2.

A disadvantage of the known device is the inaccuracy of measurements, despite the use of several humidity sensors, due to the neglect of a particular state of development of a plant requiring watering.

The purpose of the invention is to improve the accuracy of irrigation control.

The goal is achieved in that the device for automatic control of irrigation uses sensors for measuring water velocity in the stem and plant stem diameter, equipped with memory nodes whose inputs are connected to the synchronization unit and outputs to the comparison units as sensors of irrigation.

FIG. 1 shows a functional diagram of the device; in FIG. 2 is a schematic diagram of the proposed device.

The automatic irrigation control device of FIG. 1) contains sensor 1 for measuring the speed of water flow in the stem, sensor 2 for measuring the diameter of the stem, comparison unit 3,

the first input of which is connected to the output of the device 1, the comparison block t, the first input of which is connected to the output of the device 2, the storage nodes S and 6, the outputs of which are each connected to the second inputs of the comparison blocks 3 and, accordingly, the logical control unit 7, two inputs connected to the outputs of the comparison units 3 and j, and the outputs to the inputs of the storage nodes 5 and 6 and to the input of the time relay 8, the irrigation unit 9 whose input is connected to the output of the time relay 8, the synchronization unit 10, moreover, the water velocity measuring instruments in the stem and diameter with ebl, memory devices and the control unit is further connected to the outputs of the synchronization unit.

The sensors measuring the water flow rate in the plant stem and measuring the diameter of the stem contain appropriate transducers and provide DC voltage signals, which are proportional to the measured values.

Comparison units (Fig. 2) contain a DC amplifier (UFD) 11 and 12 connected in accordance with a summing amplifier circuit.

The memory devices are built on potentiometers 13 and 1, the rotating engines of which are connected to the shafts of electric motors 15 and 16 through reduction gears.

The control unit is a K1-K7 relay system. The watering time relay 24 is used to hold a certain, predetermined watering time if necessary. In this case, relay K8 25 with its contacts K8.1 turns on the power supply circuit of the watering time relay.

The irrigation unit contains a magnetic valve as a control element.

The synchronization circuit contains the instrument wake-up time switch, which controls the switching on of the memory devices, the control unit and the measuring instruments.

The principle of the device is purely physiological and is based on the simultaneous measurement of the water flow rate in the plant stem and its diameter. In the absence of soil drought, both of these values change in antiphase. In the case of dry conditions, these values change towards a decrease and the detection of water deficiency serves as a signal for watering the plants. . The device automatically analyzes the change in the two plant parameters and, if the result corresponds to the algorithm of packing watering, the command to turn on the watering block is issued. The device works as follows. The test signal from the measurement sensor (instrument) is supplied to one of the UFT inputs, as well as the DC voltage of the opposite polarity, so that if the UTP input signals are equal, the polarization relay K1 16 or K2 16 is balanced (Fig. 2) de-energized. This voltage is removed from the engines of variable resistors 13 and H (R and H2,) connected to the shafts of the motors D1 and 16.1 15 and 16. Suppose that in the initial state the engines of variable resistors are in the middle position, and the signals at the inputs of both from the potentiometers R and R that are removed from the potentiometers, the DFT channels are unbalanced, and the voltages at their outputs have the sign of the difference between the input voltages. The polarization relays K1 and K2 17 and 18, with their contacts, prepare the power circuits of the relay Kz 19 or K1 20, K5 21 or Kb 25. Signal; block - synchronization includes relay k7 23 which supplies 4-20 V through contacts K7.2 to relay KZ 19 KA 20 and K5 21 or Kb 22 and -tS B through contacts K7.1 to contacts short, 1, KJ.1, K5.1, K6.1. Shafts engines D1 and D come. d t in motion, the direction of which is determined by the polarity of the voltage at the inputs of the DFT P and 12 of both channels and, by moving the sliders of the potentiometers (R and 1) 13 and C, change the voltage supplied to the inputs of the DFT until they are not equal to input voltages. At the moment of their equality, the UFDs are x: balanced, relays K1 17 and K2 18 de-energize and break the power supply circuits of the short circuit relays Kk, Kk, K5 and Kb 13-22, which in turn break the power circuits of the motors.

1 - the closure of any of the contacts; 0 - open.

 Thus, the values of the input voltages at the potentiometers (R, AND R2) 13 and I are memorized. At the next measurement cycle (at the signal of the synchronization unit), the device automatically compares the input signals with the ones previously filled, and the device will work similarly.

The logic of the circuit operation is illustrated in the following table. Thus, when the contacts KZ.2 and K5.2 are closed, the relay K8 is activated and with its contacts K8.1 starts the irrigation time relay, which in turn opens the magnetic valve of the irrigation control and watering the plants. With other logical states of elements, watering is not possible. Thus, only with a simultaneous decrease in signals proportional to the relative speed of the water current in the plant's shoot and its diameter, does the algorithm control the irrigation of the plants occur. The use of a device that automatically determines the mode of irrigation of plants in the course of work by changing their physiological parameters improves the accuracy of controlling the irrigation since the device is not connected. It measures soil moisture, which ambiguously determines the need of plants for watering, since its value can be different for different types of soil, geographical zones, crops, and. weather conditions. The device makes it possible to more accurately determine the need for watering, since it automatically monitors the measurement of the state of the plant itself and is not affected by extraneous factors. Improving the accuracy of irrigation control, which is achieved by the proposed device, allows improving the water regime of plants and thereby increasing the yield of agricultural crops. Lg "T Tg

Claims (1)

DEVICE FOR AUTOMATICALLY -? WHOSE IRRIGATION CONTROL, including irrigation sensors, comparison units, logic control unit, time relay and irrigation unit, as well as a measurement synchronization unit, the outputs of which are connected to irrigation sensors and to comparison and logical control units, as a whole I mean that, in order to improve the accuracy of irrigation control, as sensors. Watering sensors used to measure the speed of the water current in the stem and the diameter of the stem of the plants, equipped with memory nodes, the inputs of which are connected to the synchronization unit, and the outputs to the comparison units.