SU756448A1 - Shaft angular travel-to-code converter - Google Patents

Description

The invention relates to automation and measurement technology and can be used in high-precision transducers of angular displacement in a digital code.

о AC voltage converters are known to code U> containing a saw-tooth voltage generator, comparators, inverters, control unit _; and a unit for converting a difference in duration into a digital code, including a trigger, valves, a reversible counter, and a pulse generator.

These converters can be used to convert the movement to an alternating voltage, then to convert a given voltage into a digital code.

Their disadvantages are the necessity of using additional _m Axle assemblies (sawtooth voltage generators, comparators), and the frequency error.

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The closest technical solution to the proposed one is a converter [23, containing an angle scale conversion unit, the outputs of which are connected to one input of a phase detector and a discrete phase shifter, to the other inputs of which a discrete phase shifter and a reversible counter are connected, the output of the phase detector is connected to the input controlled pulse generator and one input elements And, to the other inputs of which is connected to the output of a controlled pulse generator, valve outputs connect us with control inputs of the reversible counter.

The disadvantage of the known Converter is its low noise immunity, caused by the possibility of the appearance of false information in the inaccurate manufacture of its elements and the associated occurrence of phase scattering, changing with the frequency of rotation

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engine block conversion scale angle.

The purpose of the invention is to improve the noise immunity of the converter.

This goal is achieved by introducing decoders, inverters, additional reversible counter and control keys, the outputs of which are connected to the control inputs of the corresponding reversible counters, outputs of the And elements are connected to the corresponding first inputs of the control keys, the outputs of the inverters are connected reversible counter, the outputs of the bits of which through the appropriate decoders are connected to the inputs of the inverters and the second inputs of the control keys reversing account Chick.

The drawing shows a structural diagram of the proposed Converter.

The converter contains an angle scale conversion unit 1, the first output of which is connected to the first input of the phase detector 2, and the second output is connected to the first input of a static discrete phase shifter 3, the second input of which is connected to the output of the reversing counter 4, and the output to the second input of the phase detector 2 whose output is connected to the first inputs of aND gates 5 and 6 and a control input of the pulse generator 7. The output pulses controlled oscillator 7 is connected to the second inputs of aND gates 5 and 6 ^yields: which corresponds They are connected to the first inputs of the control keys 8 and 9 and through the control keys 10 and 11 to the inputs of the reversible counter 4, the second inputs of the control keys 10 And 11, respectively, are connected to the outputs of the decoders of the state “O’ 12 and state Ί ”13 and through inverters 14 and 15 - with the second inputs of the control keys 8 and 9, the outputs of which are connected to the inputs of the additional reversible counter 16. The outputs of the additional reversible counter 16 are connected respectively to the inputs of the decoders 12, 13.

The proposed transformation of the body works as follows. Let the angle of rotation of the input shaft of the angle scale conversion unit 1 be zero, and the number recorded in the reversible counter 4 is O. Then the basic voltage shift of the signal I) _s introduced by the discrete phase shifter 3 is zero and the inputs of the phase detector 2 are received

the reference voltage signal I) θ _η and the signal 6 _s / phase shift between which must be equal to zero. At the expense of na. basic modulation between sig—

₅ nalami at the inputs of the phase detector 2 will be a phase shift varying in close to a sinusoidal law at a frequency determined by the frequency of rotation of the motor shaft 10 January unit angle-scale _conversion? and an amplitude equal to the maximum phase shift. The signal at the output of the phase detector 2, changing according to the same law, will open alternately, depending on the sign, elements AND 5 and 6, allowing the passage of pulses from the controlled pulse generator 7 through normally open control keys 8 and 9 to the reversible counter 16.

The capacity of the reversible counter 16 is chosen such that during one half-period of interference voltage the number recorded in it approaches the extreme value "1 * without reaching it, and during the second half-period - to the extreme value" O ", also not reaching it. With this choice, the signals at the output of the decoder 12 and 13 will be zero, the control keys 10 and 11 will be closed and the state of the counter 4 will remain unchanged, i.e. there will be no fluctuations in the readings of the reversible counter 4.

When the shaft of the angle conversion unit 1 is rotated by an angle between the signals fed to the phase detector 2, a harmonic component of the noise appears, a constant phase shift proportional to the angle of rotation νΑ · The signal at the output of the phase detector 2 also acquires a constant component, due to which from the elements And, for example the element And 5, will be opened longer than the element And 6. As a result, the number recorded in the reversible counter 16 reaches the extreme value "O", and the output of the decoder 12 will appear sig Al, which, acting on the control key 8, through the inverter 14 will disable the recording of pulses in the reversible counter 16 and allow the recording through the control key 10 to the reversible counter 4. The state of the reversible counter 4 will change, and it will affect the discrete phase shifter 3, will reduce the phase mismatch. signals at the input of the phase detector 2 to

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as long as the sign of the signal at the output of phase detector 2 does not change. Then the pulses received from the controlled pulse generator 7 through the element And 6, the control key 9 to the reversing 5 counter 16, will bring the latter out of the "O" state and the circuit will return to the initial state. The number recorded in the reversible counter 4 will correspond to the angle of rotation of the shaft with / block.

If you turn the shaft to the other side, the scheme will work in the same way.

Thus, the introduction of the reference circuit parts listed elements * 1 meter readings can eliminate vibrations and thereby significantly increase the accuracy of measurement of angular displacements, and to reduce the requirements for fabrication and assembly techniques preob- ²⁰ verters angular displacement in the code.

Claims (1)

Claim 25 Angular displacement transducer into a code containing an angle scale conversion unit, the outputs of which are connected to one input of a phase detector and a discrete phase shifter, ³⁰ to the other inputs of which are connected respectively, the output of the discrete phase shifter and the reversible counter, the output of the phase detector is connected to the input of a controlled pulse generator and one input of elements AND, to the other inputs of which the output of a controlled pulse generator is connected, in order to improve noise immunity, decoders, inverters, additional reversible counter and control keys, the outputs of which are connected to the control inputs of the corresponding reversible counters, the outputs of the AND elements are connected to the corresponding In turn, to the first inputs of the control keys, the outputs of the inverters are connected to the second inputs of the control keys by an additional reversible counter, the outputs of which through the appropriate decoders are connected to the inputs of the inverters and the second inputs of the control keys of the reversible counter.