RU63143U1 - RAST TRANSFORMER TRANSFORMER TO MOVE TO CODE - Google Patents

Abstract

A raster transformer transducer moving to code relates to the field of automation and information technology. Designed to measure linear and angular displacement. EFFECT: increased metrological reliability is achieved due to the fact that a device containing a position code decoder 7, the output of which is connected to the input of the reversing counter 8, and a current source 1 connected to the input of the pulse generator of interrogation 3 and the excitation winding of the raster transformer displacement sensor 2 the read windings of which are connected to the amplitude-logic device 5, the synchronization input of which is connected to the output of the pulse shaper polling 3, a voltage control circuit is introduced 4, connected at the input to the sensor read windings, and at the output with the control input of the polling pulse shaper 3, and pulse counters 6, connected at the zeroing inputs to the output of the polling pulse shaper 3 and connected between the outputs of the amplitude-logic device 5 and the inputs of the positional decoder code 7. 1 s.p. f-ly, 5 ill.

Description

The proposed utility model relates to the field of automation and information-measuring equipment and can be used to measure linear and angular displacements.

Known raster transformer displacement sensors and converters displacement in the code based on them, which implements the amplitude-logical method of processing the output signals of the sensor [1]. Their common drawback is the low information reliability due to the lack of self-diagnosis and the strong influence of interference.

Of the known closest in technical essence is a displacement-code converter used in a four-channel universal electronic unit (Konyukhov N.E., Mednikov F.M., Nechaevsky M.L. Electromagnetic sensors of mechanical quantities - M .: Mashinostroenie, 1987, p. .228-231). Its circuit is shown in figure 1. Figure 2 shows the General case of pairing two parallel raster grids to explain the principle of operation of the raster transformer displacement sensor. Figure 3 shows a diagram of changes in voltage amplitudes on the read windings of a raster transformer sensor when moving the movable element relative to the base.

The electronic unit (figure 1) contains a device for monitoring the integrity of the communication line 1, four raster transformer sensors 2, 3, 4 and 5 of the read winding of which are connected, respectively, to the four measuring channels 6, 7, 8 and 9, a diagnostic device 10, output which is connected to the inputs of the measuring channels, and the device 11 power sensors. The composition of each of the measuring channels 6, 7, 8, and 9 includes sequentially connected amplitude-logic device 12, a position code decoder 13, count pulse generator 14, a reverse counter 15, and a digital-to-analog converter 16.

Diagnostic device 10 includes a generator of such a frequency 17 and a key 18 connected through a circuit And 19, a counter 20 and a decoder 21 with a control input of an analog key 22, switching the output signals of the transformer 23. The primary winding of the transformer 23 is connected to the output of the device 11 for supplying sensors 2, 3 , 4 and 5. The sensor supply device 11, in turn, consists of a linearly varying voltage generator 24, a voltage-current converter 25, an amplifier-corrector 26 loaded on a resistor 27, and a polling pulse shaper 28.

The operation of raster transformer sensors is based on the coupling of two raster gratings. The strokes of the first lattice (Fig. 2) are plotted at an angle φ ₁ to the abscissa axis with a step equal to λ ₁ , and the strokes of the second are plotted at an angle φ ₂ and have a pitch of λ ₂ . The intersection points of the gratings form combination bands, which are a family of parallel lines with a step of t. Thus, a scale with a division price of τ is formed. In the sensor, one of the gratings is formed by a fixed gear ferromagnetic base (stator), and the second by a movable gear ferromagnetic element (rotor). In the grooves of the base are laid sections of the reading and field windings.

The magnetic flux developed by the sections of the field windings closes between the stator and the rotor through the tooth gap, crosses the read windings and induces an EMF in them, the value of which is proportional to the magnetic conductivity of the sections of the magnetic circuit formed by the base, the movable element and the air gap between their teeth. Magnetic conductivity depends on the area of mutual overlapping of the teeth. When the relative position of the teeth of the base and the movable element of the sensor changes, a combination raster conjugation is formed, which leads to a change in the output signals on the read windings. The law of change in the amplitudes of the output signals on the read windings when moving the movable element relative to

base on the value of x - sinusoidal. Figure 3 shows the case for a sensor with four read windings and, accordingly, four voltages on them - U1, U2, U3 and U4. The period T of the voltage amplitude changes corresponds to one step of the tooth pairing. The period T is divided into a number of zones (in FIG. 3 there are eight of them Z1, ..., Z8) with a pitch of raster conjugation. The zones differ from each other by the ratio of the amplitudes of the voltages on the read windings. For example, in zone 3 (shaded in FIG. 3), U2> U3> U1> U4.

The electronic unit operates as follows. In the sensor supply device 11, a generator 24 generates a ramp voltage. Using a converter 25 and an amplifier-corrector 26, it is converted into a triangular current to power the primary windings of the sensors 2, 3, 4, and 5. Rectangular voltages appear in the sensor read windings by integrating a triangular supply current in the sensor. The amplitudes of these voltages depend on the relative position in the sensors of the fixed gear ferromagnetic base and the movable gear ferromagnetic element, namely, the area of the mutual overlapping of the teeth. The pulse generator polling 28 generates a pulse at the time of the expected maximum voltage in the read windings of the sensors. On this pulse, the comparison device in the composition of the amplitude-logical device 12 produce a pairwise comparison of the amplitudes of the voltages in the read windings of each of the sensors. As a result of the comparison, the outputs of the comparison devices of the amplitude-logical device 12 appear logical zero or one signals. The encoder of the position code 13 converts the output code combination of the amplitude-logic device 12 into a three-digit binary code corresponding to the relative position of the fixed gear ferromagnetic base and the movable gear ferromagnetic element. The pulse shaper counts 14 generates pulses on

reversible counter 15 when moving from one zone to another, that is, when the code in the decoder 13 changes. The reversible counter 15 converts the pulses of the shaper 14. The digital-to-analog converter 16 converts the output code of the counter 15 into a DC voltage to enable operation with analog recording systems.

The integrity control device of the communication line 1 checks the communication lines of the windings of the sensors 2, 3, 4, and 5 with measuring channels 6, 7, 8, and 9. In the event of a break in one of the lines, the signal “Break” is issued. The diagnostic device 10 is periodically connected to check the operability of the measuring channels 6-9 when the sensors are turned off or in the case when there is no possibility to set the movement (sensors are installed on the product). Using the key 18 at the output of the diagnostic device 10, it is possible to obtain various combinations of voltage amplitudes corresponding to the output voltages of the sensors in different positions.

A disadvantage of the known raster transformer transducer-code is the low metrological reliability, since the least reliable element of the system is a transformer sensor, which must be installed directly at the measurement site and works in the most severe conditions of temperature and vibration, is not subjected to diagnostics during operation and, in addition, the inverter diagnostics cannot be carried out continuously during operation. Interferences have a strong influence on comparing the input voltages of the sensor windings and, consequently, on the conversion result, which also reduces metrological reliability.

The inventive utility model is aimed at eliminating these shortcomings. This is achieved by the fact that in the raster transformer transformer (transformer) a movement-code containing a position code decoder, the output of which is connected to the input

a reversible counter, and a current source connected to the input of the interrogation pulse shaper and the primary winding of the raster transformer displacement sensor, the secondary windings of which are connected to an amplitude-logic device, the synchronization input of which is connected to the output of the interrogation pulse shaper, a voltage control circuit connected at the input to secondary windings of the sensor, and at the output with the control input of the pulse shaper polling, and pulse counters connected to the zeroing inputs with the output ph tors, the interrogation pulses and an amplitude included between the outputs of logic unit and the inputs of the decoder the position code.

Figure 4 presents the structural diagram of the proposed transducer displacement in the code, and figure 5 is a timing diagram of its operation. The converter contains a power supply source 1 of a raster transformer displacement sensor 2, a pulse generator 3, a voltage monitoring circuit 4, an amplitude-logic device 5, pulse counters 6, the number of which is equal to the number of outputs of the amplitude-logic device 5 and depends on the number of secondary windings of the sensor 2 , position code decoder 7 and a reverse counter 8. The output of the power supply current 1 is connected to the primary winding of the raster transformer displacement sensor 2 and the input of the pulse generator interrogation 3. The output of the interrogation pulse generator 3 is connected to the synchronization input of the amplitude-logic device 5 and the zeroing inputs of the pulse counters 6. Voltage sensing circuit 4 is connected to the read windings of the sensor 2, and the amplitude-logic device is connected at the output to the control input of the interrogation pulse generator 5. The outputs of the amplitude-logic device 5 are connected via pulse counters 6 with a position code decoder 7, and the output of the latter is connected to a reverse counter 8. All devices included in the converter Only moving to the code can be implemented

as well as in the prototype in the form of separate functional blocks. It is also possible to implement some nodes, for example, a polling pulse generator 3, a voltage control circuit 4, an amplitude-logic device 5, pulse counters 6, a position code decoder 7 and a reversible counter 8 as part of a microprocessor equipped with comparators or analog-to-digital converters, software.

The translate to code converter works as follows. The AC signal U1 (Fig. 5 shows a sinusoidal waveform, although it is possible, for example, in the form of sawtooth or rectangular pulses), the power supply 1 enters the primary winding of the raster transformer displacement sensor 2. Voltages U2 appear on the read windings of the sensor 2 the amplitudes of which depend on the position of the sensor rod at a given time. When moving the rod of the sensor 2, the voltage amplitudes on the read windings change. In the case of a rod moving at a constant speed, the law of amplitude variation is sinusoidal, and the amplitude envelope changes in adjacent windings differ in phase by the same angle (Fig. 5 shows output voltage diagrams U2.1, U2.2, U2.3, U2.4 for a sensor with four secondary output windings when the phase difference is ¼ period). The voltage control circuit 4 during the operation of the converter evaluates the values of the voltage amplitudes on the read windings of the sensor 2. If these values exceed a predetermined minimum level, the control circuit 4 generates a signal that enables the inclusion of the polling pulse generator 3. Otherwise, the sensor has a malfunction, for example , open circuit or short circuit of one of the windings, the polling pulse generator 3 does not turn on, and the control circuit 4 indicates a malfunction. Voltage monitoring can be carried out both once at the moment of switching on the sensor, and continuously throughout the entire operation time.

After switching on, the generator 3 generates a packet of pulses U3 for polling comparators 5-8. The time pulses U3 are located symmetrically relative to the moments with the maximum voltage on the read windings of the sensor 2. The first pulse U3 is reset to pulse counters 6. For each pulse U3, the amplitude-logic device 5 compares the amplitudes of the voltage U2 on the read windings of the sensor 2. As a result of the comparison to the counting input the corresponding pulse counter 6 serves "0" or "1" depending on the ratio of the input compared voltages. If the number of units is greater than or equal to half the number of pulses U3, then an overflow signal appears on the output of counter 6, which goes to logic 7. Using logic 7, which analyzes the output signals of pulse counters 6, zones Z1, Z2, Z3, Z4 are recognized , Z5, Z6, Z7, Z8 inside the pitch of the tooth pairing. For example, in zone 33, U2.1> U2.2> U2.4> U2.3. Logic 7 generates a zone number code. Counter 8 captures this code and then incrementally increases or decreases it by one each time the zone number code is changed.

The introduction of a voltage monitoring circuit 4 allows for continuous monitoring of the sensor and determining the moment of occurrence of a malfunction, thereby increasing the metrological reliability of the displacement-code converter. Repeatedly performing the voltage comparison operation can significantly reduce the effect of interference on the comparison result.

Claims (1)

A raster transformer transducer for moving to a code containing a position code decoder whose output is connected to the input of a reversible counter, and a current source connected to the input of the polling pulse shaper and the primary winding of the raster transformer displacement sensor, the secondary windings of which are connected to an amplitude-logic device, synchronization input which is connected to the output of the interrogation pulse shaper, characterized in that a voltage control circuit connected in input is introduced into it with the secondary windings of the sensor, and at the output with the control input of the polling pulse shaper, and pulse counters connected to the zeroing inputs with the output of the polling pulse shaper and connected between the outputs of the amplitude-logic device and the inputs of the position code decoder.