RU1781673C - Positioning device - Google Patents

Abstract

The invention relates to a technique for controlling the mechanisms of a production vehicle. The purpose of the invention is to increase accuracy by increasing noise immunity. The device comprises serially connected reference unit, adder, digital-to-analog converter, non-linear converter, analog dual-circuit drive speed control system, movable object, serially connected pulse displacement sensor and driver, as well as a reversing counter and two indicators. What is new in the system is that it additionally incorporates a track sensor, a control element, two comparators, an I element, a trigger, a key and a single vibrator, which allow changing the structure of the control system during the movement of a moving object. 2 ill. next to

Description

The invention relates to the field of controlling the mechanisms of industrial transport, namely: cranes, bogies, carriages, live rolls, etc.

A device is known for automatically stopping a vehicle at a predetermined location, comprising a movable object (vehicle), track sensors, a control system comprising an engine, a thyristor converter, a tacho generator, a speed controller (a mode adjusting unit) and a reference unit (a command command controller). The positioning accuracy of this device is limited for a variety of reasons. Firstly, low positioning accuracy is caused by the use of strain gauge elements having a wide range of parameters as track sensors, and secondly, positioning accuracy depends on the symmetry of the load on the vehicle, because a shift in the center of gravity of the load directly causes a positioning error.

Devices for positional stops of carts are also known, comprising a movable object (cart), a pulse sensor, counters, a reference unit (signal source), and indication devices. The positioning accuracy of these devices is insufficient: firstly, it is limited by the insufficient sensitivity of magnetic shunts; secondly, these devices are not controlled by

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trolley burning when a sensor interacts with magnetic shunts; thirdly, there is not a smooth, optimal decrease in speed in the braking section, but a stepwise reduction in speed with uncontrolled coasting occurring in the last technological section.

A digital automatic control system is also known, comprising a reference unit (master), an adder, a digital-to-analog converter (code-voltage converter), a thyristor converter (amplifier), a motor, a pulse displacement sensor (feedback sensor) and logic elements, positioning accuracy in such a system is limited for the following reasons: firstly, due to the lack of a speed control system for a moving object, it is difficult to ensure clear positioning when changing the load of the engine (varying weight of the load) during the process; secondly, often with a reasonably selected number of bits of the reference block and the adder, the weight of each bit is forced to limit due to large movements of the moving object, which reduces the accuracy of positioning.

Closest to the technical nature of the proposed system is a positional system with a pulse displacement sensor, comprising a reference unit, an adder, a digital-to-analog converter, a non-linear converter, an analog dual-circuit drive speed control system, a moving object (mechanism), a pulse displacement sensor, a shaper, a reversible counter and two indicators. The positioning accuracy in such a system is reduced due to insufficient noise immunity associated with the use of a skid when the moving object is moving and slipping, on the shaft of which a pulse displacement sensor is installed. With skidding and wheel slipping, the correspondence between the number of pulses generated by the pulse displacement sensor and the true movement of the moving object is violated. This drawback of the system affects the accuracy of positioning, especially with large movements of a moving object.

The aim of the invention is to improve positioning accuracy by increasing the noise immunity of the system.

This goal is achieved in that a positioning device comprising a series-connected digital reference unit and an adder, a digital-to-analog converter, a non-linear converter, an analog dual-circuit drive speed control system

(ADSUSP), a moving object, a pulse displacement sensor, a pulse shaper, as well as a reversible counter, the output of which is connected to the second input of the digital adder, and two indicators, additionally equipped with a direction sensor, control, two comparators, a logical element And, trigger, key and one-shot, and the track sensor is installed in front of the positioning axis on

5 minimum distance (this distance is hereinafter referred to as the positioning zone), sufficient to stop the movable object on which the control is mounted, the input of the first comparator is the key to the output of the digital adder, the input of the second comparator is connected to the ADSUS output, the outputs of the comparators are connected to the inputs logical element And, the trigger inputs are connected to the outputs of the logical 5th element And and the path sensor, the output of the trigger is connected to the control input of the key connected between the output of the driver number of inputs and the input of a reversible counter, the input of a single-shot is connected to

0 to the output of the logic element AND, and the output of the single-shot is connected to the inputs of the reset of the reversible counter and the digital reference unit.

The presence in the inventive device of a path sensor and a control element, allowing to determine the moment of entry of a moving object into the positioning zone, two comparators and a logical element And, allowing to determine the moment

0 achievement by the moving object of the positioning axis, in the absence of a mismatch between the task to move and the true movement of the moving object, as well as the moment of speed reduction

5 movable objects to zero, a trigger and a key, allowing you to connect or disconnect feedback by position, also a one-shot, allowing you to set zero reverse values

0 counter and the reference unit, we consider significant differences for the claimed device.

Changing the structure of the positioning device, which consists in connecting 5 position feedback at the moment a moving object enters the positioning zone and disabling position feedback while restoring the zero values of the reversing counter and the reference unit at the moment of reaching

moving object of the positioning axis in the absence of a mismatch between the moving task and the true movement of the moving object, improves positioning accuracy by increasing the noise immunity of the device.Increasing the noise immunity of the device is achieved by eliminating the influence on the quality of steering control and wheel slippage on the shaft which is installed a pulsed motion sensor when moving a moving object outside the positioning zone.

In FIG. 1 shows a block diagram of the proposed device; in FIG. 2 is a layout diagram of some elements of the device.

The positioning device comprises a series-connected digital task unit 1, a digital adder 2, a digital-to-analog converter 3, a non-linear converter 4, an analog dual-circuit drive speed control system 5 (ADSUSP), a moving object b, a pulse displacement sensor 7, a pulse shaper 8, a key 9 and a reverse a counter 10, the output of which is connected to the second input of the digital adder 2, as well as to the indicator 11, and the indicator 12 connected to the output of the task unit 1. In addition, the device includes a track sensor 13, which determines the beginning of the positioning zone of the movable object 6, on which the control element 14 is installed, a comparator 15, the input of which is connected to the output of the digital adder 2, a comparator 16, the input of which is connected to the output of the ADSUS 5, a logical element And 17, the inputs of which are connected to the outputs of the comparators 15 and 16, a trigger 18, whose inputs are connected to the outputs of the logical element And 17 and the path sensor 13, and the output to the control input of the key 9, and a one-shot 19, the input of which is connected to exit logical element And 17, and the output to the inputs Reset of the reversing counter 10 and the digital unit 1 of the job.

The device operates as follows,

In the initial state, at the output of the digital task unit 1, the signal is zero. Accordingly, the output signals of the digital adder 2, the digital-to-analog converter 3 of the nonlinear converter 4, ADSUSP 5 are equal to zero; the movable object 6 is at rest, the output signals of the pulse displacement sensor 7 and the pulse shaper 8 are not generated, the key 9 is locked, the output signal of the counter 10 is equal to zero, the indicators 11 and 12 are indicated, the zeros are indicated on the track sensor 13, the control body 14 It has no effect, at the outputs of the comparators 15, 16 and the logic element And 17 - the signal is logical 1, the trigger 18 is in a state that provides the closed state of the key 9, at the output of the one-shot 19 the signal is zero.

The move and position stop signal of the movable object 6 is a number in the forward parallel code equal to the sum of the output pulses generated by the pulse displacement sensor 7 when the movable object moves from the beginning of the positioning zone to the positioning axis. This signal is generated by the digital reference unit 1 and supplied to the first input of the digital adder 2. Since the output of the reverse counter 10 equal to zero is supplied to the second input of the digital adder 2, a signal equal to the reference signal is generated at the output of the digital adder 2. This signal is supplied to a digital-to-analog converter 3, where it is converted to analog form, then to a non-linear converter 4, where it is converted in accordance with the selected control law, and to the ADSUS 5, which drives the movable object 6 and ensures its movement at a given speed. In this case, the pulse displacement sensor 7 generates pulses of variable length (depending on the speed of movement of the moving object 6). the number of which is proportional to the movement of the moving object 6. In the pulse shaper 8, where the output pulses of the pulse displacement sensor 7 are received, the direction of rotation of the pulse displacement sensor 7 is determined, i.e. the direction of movement of the movable object 6, and these pulses are converted into pulses of constant duration, and the duration of the output pulses of the pulse shaper 8 does not exceed the duration of the output pulses of the pulse motion sensor 7 at the maximum speed of the movable object 6. However, the output pulses of the shaper 8 pulses through the key 9 do not pass, since it is still locked, at the output of the reversible counter 10, the signal no is still zero, at the output of the adder 2, the signal becomes equal to the reference signal, which ensures the constant setting of the moving speed of the movable object 6, the readings of the indicator 11 are zero, the readings of the indicator 12 are equal to the move and positional stop of the movable object 6. At the moment the digital adder 2 outputs a signal that is different from zero by the output of the comparator 15 produces a logical O signal, when a signal other than zero appears at the output of the ADSUSP 5, a signal of a logical O is generated at the output of the comparator 16. At the output of the logic element And 17 a logical O signal is also generated. In this case, the state of the trigger 18 does not change, which ensures the closed state of the key 9; at the output of the single-shot 19, the signal is still zero. In this way, the device operates in a drive speed control mode.

When the movable object b enters the positioning zone, the control body 14, approaching the track sensor 13, causes its operation. At the output of the track sensor 13, a signal is generated that switches the trigger 18 to the state in which the key 9 is opened. From this moment, the output pulses of the pulse shaper 8 through the public key 9 begin to arrive at the input of the reversing counter 10. The output signal of the reversing counter 10, generated in the additional code, is fed to the second input of the digital adder 2, thereby changing the structure of the positioning device by connecting position feedback loop consisting of a pulse displacement sensor 7, a pulse shaper 8, a reverse counter 10 and an indicator 11, the device starts to work in the reg lation position of the mobile unit 6 in the positioning area. Since the output signal of the digital task unit 1 is supplied to the first digital adder 2 in the direct code, and the output signal of the reversing counter 10 is supplied to the second input of the digital adder 2 in the additional code, an output signal from the building moving signal and the signal is generated at the output of the digital adder 2 corresponding to the true movement of the moving object b in the positioning zone. With further movement of the movable object 6, the signal at the output of the track sensor 13 disappears, because the control element 14, when removed, ceases to act on it, however, the trigger 18 remains in a state that ensures the open state of the key 9 In the process of moving the movable object (5 in the positioning zone, the error signal at the output of digital adder 2 decreases, ADCS 5

performs braking of the moving object 6 in accordance with the selected control law. When the moving object 6 reaches the positioning axis, the output signal of the reversing counter 10 becomes equivalent to the reference signal for moving and positionally stopping the moving object b, which was due to the choice of the value of this signal, at the output of the digital adder 2 produces a signal equal to zero, ADSUS 5 provides a stop of the movable object 6. When a digital signal adder 2 appears, the output is equal to 5 Well, the comparator 15 is triggered, and a logic 1 signal is generated at its output. When a signal equal to zero appears at the output of the ADSUSP 5, the comparator 16 is triggered, and a signal is generated at its output

0 is a logical 1 signal. At the same time, a logical 1 signal is also generated at the output of a logical element And 17, which causes, firstly, the switching of the trigger 18 to a state in which

5, the locked state of the key 9, and secondly, the operation of the single-shot 19. The output signal of the one-shot 19, acting on the inputs. Resetting the digital reference unit 1 and the counter 10, resets their output signals. Thus, the device is restored to its initial state and is ready for the next movement and positioning of the movable object 6 on the next positioning axis.

5 As an example of hardware implementation of the input elements of the positioning device, we can name the following list of functional control cells for production according to KHEMZ: comparators-YaFU0 0029 and YaFU-0271, logic element I-YaFU-0162, trigger-YaFU-0278, key-YaFU-0151 , single vibrator-YaFU-0333. The functions of the pulse shaper are performed by the control cell YaFU-1248. Functions performed by these

5 elements can also be implemented on programmable computer technology. The limit switch contactless type KVD-25 and

0 metal plate.

Thus, the positioning device when moving a moving object outside the positioning zone is a drive speed control system, and

5 when moving a movable object in a positioning zone by a system for adjusting the position of a moving object.

Changes in the structure of the positioning device are carried out using a track sensor, a control, two

comparators, logical element AND, trigger, key and one-shot. When the wheel is skidded and slipping, on the shaft of which a pulse displacement sensor is mounted, the correspondence between the number of pulses generated by the pulse displacement sensor and the true movement of the moving object is violated. When used, fewer pulses are generated; when skidding, more. A pulse displacement sensor as one of the links in the feedback loop is part of the position control system and is not part of the speed control system. Therefore, the use and skidding of the wheel, on the shaft of which a pulse displacement sensor is installed, when moving a moving object outside the positioning zone, does not affect the quality of regulation, i.e. do not reduce positioning accuracy.

Changing the structure of the positioning device during the movement of a moving object, in which the position feedback loop is closed in the positioning zone and open outside the positioning zone, eliminates the influence on the quality of positioning of the skid and skidding of the wheel, on the shaft of which a pulse displacement sensor is installed when moving a movable object outside the positioning zone, i.e. the noise immunity of the positioning device is increased in proportion to the ratio of the total path of the moving object to the positioning zone.

Claims (1)

The claims A positioning device containing a series-connected digital reference unit and an adder, a digital-to-analog converter, a non-linear converter, an analog two-loop drive speed control system and a moving object, a pulse transducer and a pulse shaper, as well as a reversible counter, the output of which is connected to the second the input of the digital adder, and two indicators, one of which is connected to the output of the reversing counter, and the other to the output of the reference unit, different moreover, in order to increase accuracy by increasing the noise immunity of the device, it is equipped with a track sensor with a control located on a moving object, two comparators, an And element, a trigger, a key and a single-vibrator, the input of the first comparator is connected to the output of the adder, the input the second comparator - to the output of the analog two-circuit drive speed control system, the comparator outputs are connected to the inputs of the And element, the inputs of the trigger are connected respectively to the outputs of the And element and the track sensor, in The trigger output is to the control input of the key connected between the output of the pulse shaper and the inputs of the reversible counter, the input of the single-vibrator is connected to the output of the And element, and the output of the single-vibrator to the inputs Reset of the reverse counter and the reference unit. Movement direction Positioning zone FIG. 2.