SU1124361A1 - Shaft turn angle encoder - Google Patents

Abstract

ANGLE CONVERTOR TURN THE SHAFT INTO THE CODE containing the power source, the output of which is connected to the input of the angle sensor, the first and second outputs of which are connected to the first and second analog inputs of the octant selection unit, the first and second high-speed strokes of which are connected to the analog inputs of the first and the second functional voltage dividers, respectively, the outputs of which are connected to the inputs of the subtraction unit, the reversible counter, the forward and inverse outputs of the lower bits of which are connected to the digital inputs of the first and second functions Functional voltage dividers, characterized in that, in order to improve the accuracy of the converter, a pulse driver, a key, two comparators, two triggers, three AND elements, an IL element, the input of the subtraction unit are connected via a key to the inputs of the comparators whose outputs are connected with the inputs of the first trigger, the outputs of which are connected to the first inputs of the first and second elements AND, respectively, whose outputs are connected to the first and second inputs of the reversible counter and the OR element, the output of which is connected to the first m input of the second trigger, the output of which is connected to the first input of the third element I, (O the output of which is connected to the second inputs of the first and second elements. And, the output of the power source is connected to the input of the pulse former, and the first output of which is connected to the control input of the key and the second input of the second trigger, and the second output is connected to the second input of the third element I, the outputs of the three 41st bits of the reversing counter connected to the central inputs of the vitior octant block.

Description

The invention relates to computing and is intended for use in measuring systems and digital tracking systems. The known converter of the rotation angle of the rosin of the selsyn into a digital code containing the selsyn, a transformer, an adder, two amplifiers — a limiter, a binary counter lj. The disadvantage of this converter is that the binary counter reacts not only to the useful signal, but also to the disturbance signal, whose amplitude is higher than the threshold of the binary counter control circuit. Thus, in order to ensure the noise immunity of the converter, it is necessary to increase the sensitivity threshold of the binary counter control circuit above the maximum amplitude of the interference signal, which entails a decrease in the accuracy of the converter. The closest to the present invention is a shaft rotation angle converter into a code comprising a power source, the output of which is connected to the input of the angle sensor, the first and second outputs of which are connected to the first and second analog inputs of the octant selection unit, the first and second outputs of which are connected to analog the inputs of the first and second functional voltage dividers, respectively, the outputs of which are connected to the inputs of the subtraction unit, the reversible counter, the forward and inverse outputs of the lower bits of which are connected to digital inputs of the first and second functional voltage dividers, amplifier, phase-sensitive rectifier, 2J pulse generator. The disadvantage of the known converter is low accuracy due to the influence of interference on the roar

sive counter.

The aim of the invention is to improve the accuracy of the converter.

The goal is achieved by the fact that in the converter of the angle of rotation of the shaft into a code containing a power source, the output of which is connected to the input of the angle sensor, the first and second outputs of which are connected to the first and second analog inputs of the octant selection unit, the first and second outputs of which are connected to analog inputs of the first and second

element IS 13, triggers 14 and 15 and comparators 16 and 17.

The Converter operates as follows.

Signals from the outputs of sensor 2, proportional to the sine and cosine of its angle of rotation, are received at block 4 of the octant selection, controlled by the octant code from the three highest

the bits of the reversible counter 5. The signals from the outputs of block 4 are fed further to the inputs of functional dividers 6 and 7 of the voltage, controlled by 1 functional voltage dividers, respectively, the outputs of which are connected to the inputs of the subtraction unit, rendering counter, direct and inverse outputs of lower order The poses of which are connected to the digital inputs of the first and second functional voltage dividers, a pulse shaper, a key, two comparators, two triggers, three AND elements, an OR element, and the output of the subtraction unit are connected through a key with inputs of comparators whose outputs are connected to the inputs of the first trigger, the outputs of which are connected to the first inputs of the first and second elements AND, respectively, whose outputs are connected to the nerve and second inputs of the reversible counter and the OR element whose output is connected to the first input of the second trigger, the output of which is connected to the first input of the third element I, the output of which is connected to the second inputs of the first and second elements I, the output of the power source is connected to the input of the pulse former, the first output otorrhea connected to the control input of the key and vtorm input of the second flip-flop and the second vkod connected to the second input of the third AND gate, the outputs of the three MSBs down counter connected to the digital inputs oktalta selecting unit. FIG. 1 shows the block diagram of the proposed converter of the angle of rotation of the shaft into a code; in fig. 2 is a timing diagram of the operation of the pulse former. The shaft rotation angle-to-code converter contains a power source 1, an angle sensor 2, a pulse shaper 3, an octant selection unit 4, a reversible counter 5, voltage dividers 6 and 7, a subtraction unit 8, a key 9, elements 10-12,

31

respectively, direct and inverse codes within the octant, coming from the lower bits of the reversible counter 5. Signals from the outputs of the voltage dividers 6 and 7 are fed to the inputs of the subtraction unit 8, from the output of which the error signal goes through the key 9 to the inputs of the comparators 16 and 17. By the operation of the key 9, gating pulses (UC-JPQC of Fig. 2) trigger 3 pulses coming from one output of the driver. At the other output of the imaging unit of 3 pulses there are counting pulses (D

on

scset of fig. 2), shifted relative to probing pulses by 90 degrees. The pulse sequences are synchronized with the frequency of the power supply of sensor 2, and the gating pulses coincide in time with the instant of the maximum of the error signal, and the counting pulses with the moment of transition of the error signal through zero.

With the arrival of the strobe pulse, the trigger 15 is set to one state and prepares the element 12 for passing the counting pulse through it to the inputs of the elements 10 and 11. At the same time, during the duration of the strobe pulse, the error signal through the key 9 is fed to the inputs of the comparators 16 and 17 Depending on the sign of the error signal, one of the comparators 16 or 17 is triggered, which switches the trigger 14 to the zero or one state, which, in turn, prepares the passage of the counting pulse. and through the element AND 10 or 11 to the input of the addition or the input of the subtraction of the reversible counter 5.

With the arrival of the counting pulse, the reversible counter 5 increases or decreases its code by one unit of the least significant bit (in the direction of decreasing the error signal). Od4361

The counting pulse from the output of the element AND 10 or 11 through the element OR 13 sets the trigger 15 to the zero state, which prevents 5 counts from passing to the reversible counter 5 of the counting pulse before the next gate pulse arrives. Then the cycle repeats.

If the phase of the pulses at the outputs

10, the pulse former 3 and the error signal Lp correspond to the timing diagram shown in FIG. 2, the Up signal will always be supplied to the inputs of the comparators.

15 16 and 17 at the moments of maximum of its amplitude value, which facilitates the recognition of the sign by the comparators 16 and 17, since at this moment the voltage of the disturbance determined by

20 total quadrature component,

close to zero. At the moment of arrival of the counting pulse, the key 9 is closed, and the interference cannot change the state of the comparators 16 and 17, and therefore.

25 and the state of the reversible counter 5. Applying a counting pulse at times when Up 0 reduces the level of switching noise, eliminates voltage spikes and improves the dynamics of the converter, which improves its accuracy. In addition, the probability of coincidence of random interference with the time of arrival of the gating pulse is negligible, and therefore the probability of failures of the reversing counter 5 from random interference is negligible.

The conversion on the alternating current and the supply of the gating pulses at the moments when the quadrature component of the sensor 2 signal is zero, and the countable pulses at the moments of crossing the zero of the error signal improves the accuracy of the angle converter

rotation of the shaft in the code compared to the base is about 2 times when using class 1 SCHMT and 4-5 times when using class 111 SCHT.

V

Faye. I

Claims (1)

SHAFT ANGLE CONVERTER TO CODE, containing a power source, the output of which is connected to the input of the angle sensor, the first and second outputs of which are connected to the first and second analog inputs of the octant selection block, the first and second outputs of which are connected to the analog inputs of the first and second functional voltage dividers, respectively, the outputs of which are connected to the inputs of the subtraction unit, a reversible counter, the direct and inverse outputs of the least significant bits of which are connected to the digital inputs of the first and second functional voltage dividers, characterized in that, in order to increase the accuracy of the converter, a pulse shaper, a key, two comparators, two triggers, three AND elements, an OR element, the input of the subtraction unit are connected via a key to the inputs of the comparators, the outputs of which are connected to the inputs of the first trigger, the outputs of which are connected to the first inputs of the first and second elements AND, respectively, the outputs of which are connected to the first and second inputs of the reverse counter and the OR element, the output of which is connected to the first input of the second a trigger whose output is connected to the first input of the third element And, the output of which is connected to the second inputs of the first and second elements And, the output of the power source is connected to the input of the pulse shaper, the first output of which is connected to the control input of the key and the second input of the second trigger, and the second output connected to the second input of the third element AND, the outputs of the three high-order bits of the reversible counter are connected to the digital inputs of the octant selection block. SU. ,, 1124361 1 11