SU1226086A1 - Measuring device for balancing machine - Google Patents

Abstract

The invention relates to a balancing technique, can be used in balancing machines and automatic lines, and provides an increase in the accuracy of determining the parameters of the imbalance excluding harmonics in the spectrum of the imbalance signal below the 11th. The imbalance signal from the output of the vibration sensor to the inputs of two channels of orthogonal imbalance components is converted into two orthogonal sequences of alternating pulses with an amplitude equal to the imbalance projections, after which the outputs, which are the part of the unit, are in a way that the unit has configured, which are read by means of the unbalance-controlled unbalance projections. that the spectrum of the signal at the output of the adder, in addition to the main harmonic, contains components that are suppressed by the low-pass filter. 3 il. ate tc th od od 00 05

Description

The invention relates to balancing technology and can be used in balancing machines, automatic machines and automatic lines.

The purpose of the invention is to improve the accuracy of measurement of unbalance parameters by eliminating harmonics in the spectrum of an unbalance signal near the fundamental frequency.

FIG. 1 shows a functional diagram of the device; in fig. 2 - timing diagrams explaining the operation of the blocks that form the orthogonal components of the imbalance signal at the carrier frequency; . 3 - timing diagrams explaining the operation of units of the device that generate analog control pulses; keys for measuring orthogonal components of the imbalance and switches.

The numbers at the origin of each of the diagrams in FIG. 2 and 3 indicate the element number of the functional circuit whose output is shown. The number after the slash indicates the sequence number of the corresponding output. Time diagrams 14 (1) and 14 (2) (Fig. 2) show the orthogonal components of the output signal separately, and diagram 14 (3) shows their vector sum.

The measuring device to the balancing machine contains a vibration sensor 1, two channels -2 and 3 measurements of orthogonal imbalance components, each of which is designed as a series-connected phase detector 4 (5) connected to the output of the vibration sensor 1, inverter 6 (7) and the first analog switch 8 (9), as well as the second analog switch 10 (11) connected to it by its outputs, the input of which is connected to the output of the phase detector 4 (5), successively connected to the sensor 12 of the reference signal and the driver 13 orthogonal reference signal , the first and second outputs of which are connected respectively to the second inputs of phase detectors 4 and 5, series-connected adder 14, low pass filter 15 and meter 16 unbalance values, two switches 17 and 18, each of which is made in the form of three analog switches 19 (20 ), 21 (22) and 23 (24), whose inputs connect

50

5 o

5 5 5

0

0

between each other and with the outputs of the analog keys 8 (9) and 10 (11), and the output of each of the keys 19-24 with one of the six inputs of the adder 14, the pulse generator 25, two counters 26 and Johnson 27, the inputs of which are connected respectively with direct and inverse outputs of pulse generator 25, first outputs with control inputs of analog switches 8, 10 and 9, 11 and third output of the first with synchronization output of the second, and decoder 28, made in the form of three logic elements 29-31 EXCLUSIVE OR , the outputs of which are connected respectively with the pairwise connected controls the analog inputs 19 and 20, 21 and 22, 23 and 24, the inputs of the first with the second and third inputs of Johnson’s counter 26, the inputs of the second with the second and third outputs of Johnson’s counter 27, and the inputs of the third with the first and second logic elements 29 and 30 EXCLUSIVE OR.

The device works as follows.

From the output of the vibration sensor 1, the imbalance signal is supplied to the information inputs of the phase detectors 4 and 5, to the control inputs of which two orthogonal reference signals with a rotating frequency of the balanced rotor (not shown) are supplied. The reference signals are generated by the unit 13 of forming the reference signals from the signal taken from the sensor 12. At the outputs of the phase detectors 4 and 5 there are constant voltages U and U proportional to the orthogonal components of the unbalance vector

U, KDcosy and U, KDsin, where K - coefficient of proportionality;

D is the imbalance value; - phase shift between vector

unbalance and reference signal. The outputs of the inverters 6 and 7, connected to phase detectors 4 and 5, generate constant voltages - and - and, and. The inputs of the switches 17 and 18 using analog switches 8 and 9, 10 and 11 are connected either to the outputs of the inverters 6 and 7, or to their inputs. To do this, square keys (Fig. 3) of the frequency uJ with a mutual phase shift of 90 ° are supplied to the control inputs of the keys 8.9 and 10, 11. As a result, the outputs of the switches 17 and 18 pos

The orthogonal sequences of two-pole rectangular pulses, the amplitude of which is equal to the voltage U, and U,. Each of the three keys 19, 21 and 23 of the switch 17 performs alternately in accordance with the outputs of the decoder 28 (FIG. 3) connecting the input signal to the first three inputs of the adder 14 and during the frequency period, the transmission coefficients for each of which relate as sin 15 sin 45, sin 75 °. The switch 18 works similarly, but the signals controlling its keys are shifted by 90 ° relative to the signals controlling the keys of the switch 17. The outputs of the switch 17 are connected to the second three inputs of the adder, the transmission coefficients for each of which are treated as sin 75 ° : sin 45 °: sin 15 °.

As a result, a vector sum of orthogonal components is formed at the output of the adder 14, each of which is a quasi-sinusoidal signal of the carrier frequency cJ, obtained by a stepwise approximation of the sinusoidal function with uniform time quantization.

The spectrum of the signal produced at the output of the adder 14, in addition to the main harmonic, contains the components

and

one

(, t1) u) t,

where t.- 1, 2, 3,

which are suppressed by the low pass filter 15. Thus, at the output of the low-pass filter 15, a sinusoidal signal is formed with a frequency cJ whose amplitude and phase correspond to the value and angle of imbalance. An unbalance value meter 16 connected to the output of the low-pass filter 15 records the amplitude of this signal.

The control signals of the analog keys 19-24 (Fig. 2) are generated by the decoder 28 and the signals taken from the second and third outputs of the Johnson counters 26 and 27. Each of the counters is a three-bit cross-feedback shift register. When pulses from a pulse generator 25 arrive at their counting input, square wave of the square wave type will appear at each of the three meter outputs.

5 y 260864

nominal phase shift of 120 °. The frequency oj: of these pulses is 6 times less than the frequency of the signal of the generator 25. Clocking the counter with antiphase signals and synchronizing the counter with 27 negative signal drops, detected at the third output of counter 26, ensures the orthogonality of the output signals of the counters 26 and 27.

The spectrum of the signal coming from the output of the adder 14 to the low-pass filter 15 contains only some of the odd harmonics: 11th, 13th, 23rd or 25th of the 25th, etc. since then.

To enable digital measurement of the unbalance angle, position angle and other angular

The values represented by the signal carrier frequency uJ between the output of the pulse generator 25 and the counting inputs of counters 26 and 27 Johnson can be connected in series with a divider by 30 and a counting trigger, and the frequency of the pulse generator 25 should be increased 60 times, respectively. The output pulses of the generator 25 are used as countable with a discreteness of G (or less with a corresponding increase in the division ratio

division)

The absence of harmonics near the fundamental frequency significantly reduces the distortion of the waveform at the output 35 of the low-pass filter and, accordingly, increases the measurement accuracy of the unbalance value and angle.

Claims (1)

Invention Formula 40 Measuring device to a balancing machine, containing a vibro-sensor, two channels for measuring gonal components, each 45 of which are made in the form of a series-connected phase detector connected to the output of a vibration sensor, an inverter and the first analog switch, and connected to the output 50 last by the output of the second analog key, the input of which is connected to the input of the inverter, successively connected an adder, a low-pass filter and a meter for the unbalance value, a sensor of the reference signal, an associated driver of orthogonal reference signals, the outputs of which are connected to the second inputs of the phase de- 5.1226086 Tactors, pulse generator and decoder, characterized in that, in order to improve measurement accuracy, it is equipped with two switches, each of which is made up of the first, second and third additional analog switches, whose inputs are interconnected and with the main analog outputs. the keys of the corresponding measurement channel of the orthogonal components, and the output of each additional key, with one of the six inputs of the adder, the redirecting inputs of the main first and second analog switches orthogonal component measurement channel, and the third output 5 of the first - with the synchronization input of the second Johnson counter, the decoder is made in the form of the first, second and third logical elements EXCLUDING - SIPPING OR, the outputs of which are connected 10 with the pairwise connected control inputs of the corresponding additional analog switches of both switches, the inputs of the first and second switches with the second and third outputs of the corresponding and second Johnson counters, the inputs of which are connected to the corresponding Johnson counters, and the inputs but with direct and inverse output of the third - with the outputs of the first and second pulse generator, the first logical output elements EXCLUDED each with interconnected OR. the control inputs of the main first and second analog keys of the corresponding measurement channel orthogonal components, and the third output the first - with the synchronization input of the second Johnson counter, the decoder is made in the form of the first, second and third logical elements EXCLUSIVE - THE SIPPINGOR OR, the outputs of which are connected with the pairwise connected control inputs of the corresponding additional analog switches of both switches, the inputs of the first and second switches with the second and third outputs of the respective  t FIG g 25h 26li hell hell 25/2 27 // 27/2 27 / j Compiled by J. Round Editor A. Kozorie Tehred V. Kadar Proofreader A. Ferenc Order 2112/30 Circulation: 778. Subsidy. VNIIPRT USSR State Committee for inventions and discoveries 113035, Moscow Zh-35, Raushsk nab., d. 4/5 Produced by -professional enterprise, Uzhgorod, Projecto st., 4