RU2112973C1 - Method for checking - Google Patents

Abstract

FIELD: agricultural manufacturing, in particular, stationary grain processing stations. SUBSTANCE: method involves use of alternating current power supply line for communication, generation of request signals and information signals as pulse bursts which rate is synchronized with voltage of power supply line, shift of information pulse bursts with respect to request pulse bursts by duration which is proportional to number of gauge to be requested. Clock signal is voltage of power supply line. Burst of request signals has greater number of pulses than burst of information signals. Invention specification provides principal circuit of device which implements said method. EFFECT: increased functional capabilities. 2 cl, 2 dwg

Description

 The present invention relates to agricultural engineering, and in particular to methods of controlling the technological process mainly at stationary grain processing points where it is necessary to control several technological parameters, for example, the grain level in the storage bins.

 A known method of monitoring the technological process, based on the formation of a technological sensor pulse signals and transmitting them via power buses to the input of the control unit. The specified method is implemented in a capacitive signaling device for clogging the coulters of the seeder (see AS USSR N 1724054, class A 01 C 7/00, 1992).

 The known control method has limited functionality. This is expressed in the fact that the known control method does not allow the use of an industrial network 220 V, 50 Hz as a communication line. This drawback does not allow the use of the known control method at stationary grain processing points, where an industrial network of 220 V, 50 Hz is used as power bus.

 There is another way to control the process, based on the formation by the control unit of the polling signals of technological sensors and response information signals about the controlled process by these sensors and the transmission of these signals through a common communication line. The specified method is implemented in a device for seeding control (see AS USSR N 1205797, class A 01 C 7/00, 1986).

 The known control method has limited functionality, due to the above.

 The purpose of the invention is the expansion of the functionality of the control method by transmitting information signals through an industrial network of 220 V, 50 Hz. This feature of the proposed control method allows you to control the process without using a special communication line between the sensors and the control unit, which significantly expands the scope of the proposed method.

 To achieve this goal in a known monitoring method, based on the formation by the control unit of the polling signals of technological sensors and response information signals about the process being monitored by these sensors and the transmission of these signals over a common communication line, an industrial AC network is used as communication lines, and the polling signals and information signals are formed in the form of bursts of pulses, the repetition rate of which is synchronized by the voltage of the industrial network, while the information packets of shear pulses m with respect to interrogation burst time proportional to the number interviewee process transmitter, and in use as a clock signal voltage of the commercial network. A packet of a polling signal is formed with a larger number of pulses than a packet of an information signal of any of the interrogated sensors.

 In FIG. 1 and FIG. 2 shows a structural diagram of a device that implements the proposed control method. Figure 1 shows the structural diagram of the control unit for nine control channels, and figure 2 is a structural diagram of the technological sensor of one control channel.

 The control unit (Fig. 1) contains a filter 1, passing only a sinusoidal signal with a frequency of 50 Hz to a pulse shaper 2. Filter 3 passes only high-frequency signals contained in the spectrum of information pulses to the input of a pulse shaper 4 of constant duration, and a sinusoidal signal with a frequency of 50 Hz does not pass through filter 3. The pulse converter 5 contains a switch 6, a capacitor 7, a diode 8, a resistor 9, and an “And” element 10. The output of the former 2 is connected to the clock inputs of the counter 11 and trigger 12, as well as to the input of the “And” 13 element, the output of which is through the element And "14 is connected to the input of the shaper 15 bursts of the polling pulses. The inputs of the filters 1, 3 and the output of the driver 15 are connected to the buses 16, 17 of the industrial network 220 V, 50 Hz. The power supply unit of all functional elements of the device is connected to the same buses (the power supply unit in Fig. 1, 2 is not shown).

 Button 18, "setting the initial state" through the standby multivibrator 19, is connected to the D-input of trigger 12. Elements "And" 20 - 1 ... 20 - 9 form a logical switch controlled from the outputs of the decimal decoder 21 connected to outputs 5. .. 8 bits of the counter 11. A nine-channel memory device 22 (memory), made, for example, on RS-flip-flops, is connected by information inputs to the outputs of the elements 20-1 ... 20-9, and the outputs to the inputs of the signaling unit 23, made , for example, in the form of an LED matrix and a shaper of a sound signal.

 Elements 24.. .38, which are part of the technological sensor (figure 2), have the same functionality as similar elements that are part of the control unit. The input bus 39 is designed to connect a primary Converter (not shown in Fig. 2) to the input of the standby multivibrator 40, loaded on the first input of the element "OR" 41.

 All technological sensors have the same circuit with the only difference being that the jumper 42, depending on the sensor number, is sealed during its manufacture to the corresponding input of the decoder 38 (Fig. 2 shows the sensor scheme with number 3).

 Consider the operation of the device using the proposed method, for example, when controlling the grain level in storage bins at a stationary grain processing station equipped with an industrial power supply network with a voltage of 220 V 50 Hz. In this case, the input bus 39 of each of the nine sensors is connected to the primary Converter, forming a high level logic signal (hereinafter “1”) when the controlled level passes through the set value.

 The device operates as follows. After turning on the power, press and release the button 18 (figure 1). When this starts the waiting multivibrator 19, which forms the impulse to set the system to its original state. The duration of this pulse is selected to be longer than the duration of one duty cycle, which is determined by the capacity of counter 11. With the arrival of the first clock pulse at input “C” of trigger 12, “1” is set at its output, by which counter 11 is kept in zero state, and all cells of memory 22 are reset . In addition, the operation of element 14 is blocked by the signal “0” from the inverted output of trigger 12 for the duration of the installation pulse. After the end of the installation pulse, the output of trigger 12 is set to “0”, which allows counting pulses by counter 11, and element 14 is unlocked. At zero the output of the decoder 21 during the time 16 TT is the signal "1", where TT is the period of repetition of clock pulses. Therefore, sixteen clock pulses pass through the elements 13, 14 to the input of the shaper 15, which generates a packet of request pulses synchronized by the voltage of the supply network. The formed packet, consisting of sixteen pulses, is transmitted by the output cascade of the formers 15 to the tires 16, 17.

 After passing to the input of the counter 11 sixteen clock pulses at the first output of the decoder 21, "1" is set, which prepares the element 20-1 for receiving pulses from the output of the converter 5. At the remaining outputs of the decoder 21, "0" blocking elements 13, 20-2 are stored. ..20-9. Due to this, the inputs of the device 22 are alternately connected to the output of the transducer 5 for a time Tp = 16 TT, thereby providing a temporary selection of information signals from the output of the transducer 5.

 In the absence of irregularities in the controlled technological process, at each time interval Tp, an information signal is generated and transmitted to buses 35, 36 in the form of a packet of eight pulses by the corresponding technological sensor. The sensor circuit (Fig. 2) is constructed so that the temporary position of the packet of information pulses from the sensor with the number K corresponds to the moment of connecting the output of the converter 5 to the input of the storage device 22 having the number K.

 Converter 5 operates as follows. With the arrival of a pulse information packet from each sensor at the input of filter 3, a burst is formed at the output of shaper 4, which consists of eight pulses normalized by the duration, which periodically close key 6. As a result, “0” is stored on the capacitor 7 and at the output of element 10. In this case, “0” is also stored at the outputs of the memory device 22, and the signaling device 23 informs the operator about the correct course of the controlled process. The specified monitoring process proceeds cyclically and during one cycle, each sensor generates one packet of information pulses shifted relative to the survey packet. The duration of the polling cycle is determined by the capacity of the counter 11 and the frequency of the supply voltage. At the beginning of each cycle, when "1" is set at the zero output of the decoder 21, a request signal is generated in the form of a packet of sixteen pulses.

 If there is a violation of the technological process in any control channel, the corresponding sensor does not form an information packet of pulses, and at the output of element 10, a “1” is formed in the time interval corresponding to the number of this sensor, which is recorded in the memory cell 22 with the corresponding number. In this case, the indicator light turns on in the signaling device, corresponding to the sensor number, which recorded a violation of the process. The light signal is duplicated by an audio signal. These signals notify the operator of violations.

 After eliminating the violation, the operator again presses the button 18 on the control unit and the cyclic operation of the device resumes.

 The process of generating information signals, consider the example of the sensor with number 3, a diagram of which is shown in figure 2.

 When the power is turned on, the counter 37 is set and then kept in the zero state by the signal "1" from the zero output of the decoder 38, which, through the resistor 32, the element 41 is fed to the input of the counter 37. In this state, the circuit is in the standby mode of the polling signal.

 When a polling signal in the form of a packet of sixteen pulses arrives along the power circuit (bus 35, 36), a packet of sixteen pulses of normalized duration is formed at the output of the former 27. As a result of this, the capacitor 30 is discharged through a key 29, a “0” is set at the input R of the counter 37 and the counting of clock pulses from the former 25 to the input C of the counter 37 begins.

 After sixteen clock pulses are received in counter 37, “1” is set at the first output of decoder 38, and “0” at its other outputs. Due to this, after the completion of the survey burst, “0” is stored at the input of the counter 37, and it continues to operate in the clock pulse counting mode. In this mode of operation, the pulses of a duration of 16 Tt, shifted in time relative to the polling packet, alternately appear at the outputs of the decoder 38.

 When “1” appears at the third output of the decoder 38, it prepares the element 33 for transmission of clock signals. The second input of the element 33 receives pulses from the output of the fourth discharge of the counter 37. Therefore, eight clock pulses pass through the element 33, and the driver 34 generates an information signal in the form of a packet of eight pulses, which is fed to the buses 35, 36. As can be seen from figure 2 , the temporary position of the information packet of pulses relative to the polling packet is determined by the output number of the decoder 38, to which the jumper 42 is soldered.

 After the counter 37 is overflowed, at the zero output of the decoder 38, “1” is set again, which stops the pulse count and the circuit goes into standby mode of the interrogation packet from the control unit. With the arrival of the next packet of polls, a new sensor cycle begins in a similar way.

 If there is a violation of the process, then the signal from the primary Converter, which enters the bus 39, starts the waiting multivibrator 40. The duration of its pulse is selected so that it is longer than the duration of one cycle. The output pulse of the multivibrator 40 through the element 41 keeps the counter 37 in the zero state for one full cycle. Due to this, in this cycle, the sensor information signal is not formed, which is recorded by the control unit.

 After the end of the pulse of the multivibrator 40, the circuit again enters the cyclic mode of operation, and the beginning of each cycle begins with the arrival of the polling signal in the form of a packet of sixteen pulses.

 Using the distinctive features of the proposed control method, it can significantly expand its field of application due to the transmission of information signals from control sensors via industrial power supply buses 220 V, 50 Hz. Due to this, no special communication circuits between the control unit and process sensors are required.

 It should be noted that the proposed control method is advisable to use in other areas of the national economy. In particular, when building alarm systems, as well as fire alarm systems, as these systems are installed, as a rule, in rooms equipped with an industrial power supply network of 220 V, 50 Hz.

Claims (2)

 1. The control method, based on the formation by the control unit of the polling signals of technological sensors and response information signals about the process controlled by these sensors and the transmission of these signals on a common communication line, characterized in that the industrial AC network is used as the communication line, and the polling signals and information signals are formed in the form of bursts of pulses, the repetition rate of which is synchronized by the voltage of the industrial network, while the information bursts of pulses shift relative packs poll for a time proportional to number interviewee process transmitter, and in use as a clock signal voltage of the commercial network.  2. The method according to claim 1, characterized in that the packet of the polling signal is formed with a larger number of pulses than the packet of the signal informing about the process in progress in each controlled channel.

Images