SU1037179A2 - Angular speed measuring converter - Google Patents

Abstract

MEASURING CONVERTER ANGULAR VELOCITY auth. 964540, characterized in that, in order to expand the range, increase accuracy and linearity at the lower limit of the operating range, the period-voltage converter is designed as a frequency-code converter with a variable conversion factor, one-voltage / voltage-voltage-voltage converter, a controlled voltage divider control circuit, the comparator output is connected to the control circuit input with the signal input of the frequency-code converter, the control input of which is connected to the control input of the code-voltage converter, controlling the controlled entry emogo voltage divider and to the output control circuit, and an output - to a data input of the code converter-voltage one of j outputs which G) connected to the control input of the comparator, and the other - the signal input of the controllable voltage divider.

Description

The invention relates to a measurement technique and can be used to convert the speed of rotation of shafts and other rotating elements into an analog electrical signal.

According to the main author. St. 964540 | is known for measuring transform; an angular velocity tel comprising successively connected-inductive {pick-up sensor and shaper named | Pulses, which is made in the form of a comparator with an adjustable response threshold and a period-voltage converter, with the output of the induction sensor connected to the signal input a comparator, the control input of which is connected to the output of the period-voltage converter, and the output to the input of the period-voltage converter fl.

The signal from the induction sensor. arrives at the signal input of the comparator, and from its output - at the input. the period-voltage converter 7 whose output signal is fed to the control input of the comparator and changes its threshold. The magnitude of the threshold change is determined by the noise immunity conditions; with increasing angular velocity, the threshold value increases from the minimum allowable to the working one. The output signal of the comparator has a pulsed form, and the signal from the output of the converter period-voltage depends nonlinearly on the angular velocity and cannot be used in systems of automatic rotation speed control, i.e. the control voltage of the comparator does not fully match optimal value.

The purpose of the invention is to expand the range, increase accuracy, and lee. linearity at the lower limit of the range of work. ,

The goal is achieved by the fact that in the angular velocity transmitter the period-voltage converter is made in the form of a frequency-code converter with a variable conversion factor, a code-voltage converter, a controlled voltage divider and a control circuit, the comparator output being connected to the circuit input control With the signal input of the frequency-code converter, the control input of which is connected to the control input of the code-voltage converter, to the control input of the controllable voltage divider and voltage control circuit to the input and output - data input of a code-converter voltage kotbrogo one output coupled to the control input of the comparator and another input signal with a controlled dolitel voltage.

FIG. 1 is a schematic diagram of a rotational angular velocity transducer. in FIG. 2 - amplitude-frequency characteristics.

The device includes an induction sensor 1, a comparator with an adjustable response threshold 2, and a period-voltage converter 3, which contains a frequency-code converter with a variable conversion factor 4, a code-voltage converter. 5, a controlled voltage divider b and a control circuit 7, the signal input 8 of the comparator 2 is connected to the sensor 1, and the output of the commutator 2 is connected to the input of the control circuit 7 and the signal input 9 of the frequency-code converter whose output is connected to the information input 10 of the converter voltage code.5, and its output 11 is connected to the signal input of voltage divider b, the output of the control circuit is connected to the control inputs of converters 4.5 and divider b, the control input 12 of comparator 2 is connected to output 13 of code-converter 5 .

The measuring transducer of angular velocity works as follows.

When the shaft or other object is rotated, the angular velocity of which is to be measured, the magnetic field of the induction sensor 1 is modulated, for example, by changing the magnetic flux passing through the gear disk of the sensor associated with the object of rotation. At the output of induction sensor 1, a signal appears, whose shape is close to sinusoidal, the frequency is directly proportional, and the amplitude depends nonlinearly on the angular velocity of rotation of the object. The signal from the induction sensor 1 is fed to the signal input 8 of the comparator 2, for example, an operational amplifier covered by positive feedback. The rectangular-shaped output signal from the comparator 2 is fed to the input of the control circuit 7 and to the signal input .3 of the frequency-code 4 converter with a variable conversion factor, for example, with a switchable reference generator. The output signal of converter 4 is digitally fed to information input 10 of code-converter 5, the voltage at output 11 of which depends linearly on the digital information recorded in converter 5, and the voltage at output 13 controlling the threshold of the comparator 2, is determined by uyol. TIES of the optimum noise immunity of the device. Converter 5 generally contains two code-voltage transformation matrices. The voltage from the output 11 of the converter 5 is fed to the signal input of the controlled divider 6, the output of which is the analog output of the device Output 1. The control circuit 7 when the signal frequency exceeds a certain level, for example 20% of the working range of the device, switches the conversion factor of the converter 4, disconnecting the output 13 of the converter 5, switching the transmission coefficient of the controlled voltage divider 6. The outputs of the frequency-code converter 4 and the control circuit 7 are digital m output y of the output. Output 2. With an increase in the angular velocity of rotation, the signal from the output of the induction sensor 1 increases and then decreases and stabilizes at a certain level, as the electromotive force and induction resistance of the sensor coil increase with increasing angular velocity. The elements of the matrix at the output 13 of the converter code-voltage 5 are chosen so that when the frequency changes, the signal at the output of the induction sensor from zero to the level corresponding to the switching level of the control circuit 7, the threshold of operation of the comparator 2 is determined by the conditions of optimum noise immunity.

When increasing the frequency of the output signal of the comparator 2 from zero to

The selected triggering level of the control circuit 7 of the output of the frequency converter code 4 varies within the limits corresponding to the voltage change at the output of the code voltage converter 5 from zero to the maximum value of the conversion range. When the frequency of the output signal of the comparator 2 is exceeded, the operation level of circuit 7, for example, compares the input frequency with setpoint. Noah, the control circuit produces; switching the conversion factor of converter 4, for example. by switching the frequency of the reference oscillator generator, the voltage at the output of converter 5 changes accordingly. At the same time, the transfer ratio of the controlled voltage divider b changes, for example, on a precision op amp that provides accurate matching of the ranges of converter operation.

The amplitude-frequency characteristics of the induction sensor, the operation threshold of the comparator, the control circuit, the coding voltage converter, the controllable divider, and the output voltage dependence on the Output 1 versus frequency are shown in FIG. 2

The proposed converter is noise-resistant, has high linearity and accuracy, including in the lower part of the conversion range, and provides operation over a wide range of measurement and speed control.

Claims (1)

MEASURING CONVERTER OF ANGULAR SPEED »964540, characterized in that, in order to expand the range, increase accuracy and linearity at the lower limit of the operating range, the period-voltage converter is made in the form of a frequency-code converter with a variable conversion coefficient, a pre-converter / code-voltage controlled voltage divider and control circuits, the output of the comparator connected to the input of the control circuit with the signal input of the frequency-to-code converter, the control input of which is connected to the control input of the code-voltage converter, to the input to control the controlled voltage divider · and to the output of the control circuit, and the output to the information input of the code-voltage converter § one of the outputs of which is connected to the control input of the comparator, and the other to the signal input of the controlled voltage divider. 44 "./ SU ,,., 1037179>