SU378848A1 - DEVICE FORMATION OF THE CONTROL SIGNAL - Google Patents

Description

one

When controlling drives that move a load from one point to another, it is necessary to withstand a certain law of motion — a speed diagram. Usually, for the majority of mechanisms (elevators, pitch lifts, wrenches, caval roads, and the like), acceleration and deceleration are carried out with constant acceleration, i.e., according to a linear law. The most significant is the accuracy of execution, the retardation section, which affects the accuracy of the mechanism stop and the time of approval. The formation of the control signal applied to the input of the automatic speed control of the drive is performed as a function of the V / 2cSp path during acceleration and deceleration, where V is the current speed value;

MIND - maximum speed; a is the magnitude of the acceleration (retardation);

SP is the path counted from the start of acceleration;

5h is the path counted from the beginning of the slowdown.

Nowadays, in industrial automation systems, switching mechanisms, the formation of a control signal is carried out by means of analog

methods and electromechanical devices that implement these methods. Therefore, speed control systems have low accuracy and reliability. The low accuracy of setting the reference signal with the help of profiling disks (especially in the slowdown section) leads to an increase in the time of completion and a decrease in the productivity of the mechanism. The accuracy of the permutation cycle is determined by the quality of the profiling disk, which implements the law V U2a8, its dimensions, the quality of kinematic connections. The use of profiling disks in systems operating at several points and at different speeds is difficult.

A device for generating a control signal for automatic speed control systems of permutation mechanisms is known, comprising summing and reversing counters, a comparison circuit and a threshold element, a gate and a trigger.

The purpose of the invention is to improve the accuracy and reliability of the device.

This is achieved by the fact that the input of the device through the valve, opened with the help of a trigger by the signals "Start and" Start of deceleration and closed by the signal "Stop and" Maximum speed, is connected to the input of the summing counter, the output of which is connected to one input of the comparison circuit, and A reversible counter output is connected to its other input. The output of the comparison circuit is connected to the input of the reversible counter and the reset bus of the summing counter, the signals for the reverse of the reversible counter receive the signals "Start and Start for | Slow", and the output of this counter is connected to the input of the threshold element that forms the maximum speed signal and the device output . The drawing shows a block diagram of the proposed device. The device contains an input 1, a valve 2, a summing counter 5, a comparison circuit 4 GiggeG7 GHz and / or Input 1 of a control signal generating device through a valve 2 connected to the input of a summing counter 3. The valve is also connected to trigger 7, which receives signals "Start," Start of deceleration., Maximally fast ". C ™" .. Signals from the outputs of summing counter 3 and reversible counter 5 are fed to comparison circuit 4, the output of which is connected to the input of the reversible counter 5 and the reset bus, to zero sushchy summing about. / 1 ./ counter 3. The output code of the reversible counter is a digital control signal for the automatic speed control systems and arrives at the output 5 of the device. G-cho The same code arrives at the threshold element 6, into which a code of a given, maximum speed is previously entered. The device works as follows. The counters are preliminarily set to the zero state, and the input 1 is connected to the sensor, the path pulses, which can be photoelectronic, inductive, matODmodulation, etc. The sensor is designed to form the path name of the switching mechanism by the value of the selected path quantum . The quantum size is determined by the chosen precision of the variable, nor by the speed and stop of the mechanism. When the start trigger 7 command is given, the position at which the valve 2 opens and the input path pulses enter the input of the summing counter 3. The comparison circuit 4 and the reset circuit of this counter form a feedback setting the counter to the zero state,. when the code of the summing counter 3 reaches the code that was at that moment B. time in the reversible counter 5. The comparison circuit works according to the logic "more: -. less. The occurrence of a signal at the output of the comparison circuit causes the summing counter 5 to zero and an increase in the code of the reversible counter 5 by one. The “Start” command sets the direction of the work, the reversive counter 5 is for addition. If we denote the current frequency, the path quanta by fji, and the frequency of occurrence, of the signal at the output of the comparison circuit through fi, then we can write down that fi is where Ut is the current code of the reversible counter 5. In turn, U., i.e. fi. Excluding fi from our equation, we obtain the dependence Utmt M or after integrating both parts: f. where 5p is the path from the moment of launch. This suggests that the code is reversible. counter U. 25 is the control signal for the speed control system as a function of the path. The acceleration acceleration intensity,) can be set by maximizing the magnitude. In discrete systems, the speed control code is used directly, and in analogue transducer systems, JfS p e7i7pTz ™ G Ge. RosG ™ „,.„ „, L, .., L„. . ::. reversible counter 5, occurs until, until the UT code reaches a predetermined value of the MIND. In this case, the threshold element 5 is triggered and the UM signal appears at its output, which by means of Trigs 1, LK Ml I UIUUDIH closes gate 2. The mechanism to the point is set, and the command “Start of fertility opens the century .jmanAci Matrix (ocivicA «yic; nnn // ji) UDiDCi i Dcn and set, and iv. The direction of work J, 5 on the subtraction. This 1, t2. may be generated by any path control device, for example, a counter counting path pulses. With signals that occur at the output of the circuit, cause a decrease in the code j ..f of the version counter 5. The UT code changes according to the law. v, where 5s is the path counted from the start of the slowdown. | Upon reaching the destination. The command "Stop locks valve 2." Subject of the invention. A control signal generating device for the automatic speed control systems of the permutation mechanisms, comprising a summing counter, the first input connected to a venpigil, and an output to the comparison circuit, a reversible counter, a threshold element and a trigger, characterized in that , in order to increase the accuracy and reliability of the device, the output of the reversible counter is connected to the output of the device and through a threshold element to one arm

the trigger, the other arm of which is connected to the inputs of the reversible counter connected to the input buses, the second input of the comparison circuit is connected to the reversible counter, and the output to the summing and reversing counters.

Start Start

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