SU1619155A2 - Apparatus for electromagnetic inspection of objects - Google Patents

Abstract

The invention relates to a measuring and control technique and is an improvement of the invention according to the author. St. No. 1427283. The purpose of the invention is to increase speed. The device for electromagnetic control of objects contains a power source made of frequency controlled, two inductive converters connected to it, a ring diode switch, the outputs of the inductive converters are connected to two points of the same diagonal, and an integrator connected to the other diagonal is connected to the input a time limit block, a measurement block connected to the output of the time limit block, connected in series to the frequency recorder and an element of an object in the control zone and a voltage source frequency control unit, the outputs of which are connected respectively to the control input of the power source and the first input of the pulse counter, the second input of which is connected via a level limiting unit to the output of the integrator 3 or amp & & WITH

Description

The invention relates to a measuring and control technique and is an improvement of the invention according to the author. St. No. 1427283.

The purpose of the invention is to increase the speed of the device by limiting the residence time of the object in the converter.

FIG. 1 shows a functional diagram of a device for electromagnetic control of objects; in fig. 2 - time diagram of the process of forming the output voltage and its time limit; in fig. 3 is a time chart of the process of forming the output voltage and limiting its level.

The device contains two identical inductive converters 1 and 2. connected to two nodes of the same diagonal of the ring switch 3, to the other diagonal of which the integrator 4 is connected, which contains two storage (integrating) capacitances. A time limit unit 5 is connected to the output of the integrator 4, which is a time interval generator and logic AND, which limits the time required to form the output voltage, to the output of which the output voltage converter 6 is connected to a code. The output of the controlled power supply 7 is connected to the converters 1 and 2, as well as to the operating input of the pulse counter 8, the control input of which is connected to the output of the level limiting unit 9 representing coO

ABOUT

ate

to

the battle is a source of reference voltage and a comparator and a limiting output voltage level. The input of the level 2 level is connected to the output of the integrator 4. The input of the controlled power supply 7 is connected to the output of the voltage frequency control unit 10 of the power supply, the information input of which is connected to the output of the frequency element appearance recorder 11 trol

The device works as follows.

One of the transducers 1 is installed in the zone of occurrence of the protruding magnet of the conductive element 12 of the construction of the object 13 of the control. With the passage of this element in the area of the sensor 1, the parameters of this sensor change and take the values: by active resistance n 0 and Dg, by inductance Li LO + D1. The second transform 2 is set in the same temperature and vibration zone so that the element of the control object 13 does not change its parameters, i.e. rg r0 and L.2 LO, where r0 is the active resistance of the sensor coils; Dg - introduced imbalance of resistance; LO- inductance of sensor coils; inductance imbalance.

A triggering pulse is supplied from the power frequency control unit 10, which is a voltage-to-frequency converter. The voltage on the unit 10 is supplied from the recorder 11 of the frequency of occurrence of the object, which is built for the rotating objects on the generator. The joint operation of a controlled power supply 7, a power voltage frequency control unit 10, and a recorder 11 of the frequency of occurrence of an element of an object 13 in the sensor zone ensures the ratio of time intervals

tu toe,

where tu is the pulse duration of the supply voltage;

toe is the time the object is in the sensor zone;

TI period of supply voltage pulses.

With such a ratio of time intervals, the current I flowing through the circuit-inductive converter 1, defined by the inductance LO + AL and resistance Go + Lg, during the positive supply voltage pulse across the circuit through the ring switch 3 charges the first and discharges the second storage capacitor of the integrator 4, and the current la through the winding of the inductive converter 2, defined by the inductance and resistance r0, discharges the first and charges the second capacitor of the integrator 4. When the supply voltage is negative, dithe reverse process. The charging mode of the first storage capacitor of the integrator 4 is due to the currents I and g, as well as the voltage UK-L where K is the pulse number generated on this capacitor by the beginning of the period in question, and the charge of the second capacitor of the integrator 4 is caused by the currents 12 and I, as well as the voltage 11k-1 generated on this capacitor by the beginning of the period in question. The supply voltage pulses corresponding to the absence of the element 12 of the object 13 of the control in the zone of the converter 1 do not introduce an imbalance of parameters, so

AS WITH THIS, M G2 Go, currents C & I

ia are the same; they do not change the voltage at the storage capacitors of the integrator 4. The transient mode lasts until the integral values of the charge and discharge currents of the storage capacitors of the integrator 4 become equal. After a transient period, the voltage U U +1) is set at the output of integrator 4 where U is the steady-state voltage on the first storage capacitor of the integrator, I) is the steady-state voltage on the second accumulator capacitor of the integrator. The duration of the transient determines the measurement time and limits the speed of the device.

The voltage at the output of the integrator 4 at any time is unambiguously determined by the introduced unbalance of inductance D L and practically does not depend on D g. The number of pulses N corresponding to the transient mode is determined by the unbalance of active resistance D g. Practically does not depend on D L

Time limit unit 5 is a time interval driver and logic circuit AND whose input is connected to the output of integrator 4, the output to the output voltage to code converter. Level limit unit 9 is a voltage source and a comparator, the input of which is connected to the output of the integrator 4, and the output to the control input of the pulse counter 8. Their action is illustrated in FIG. 2, which show the graphs of the formation of output parameters (output voltage and pulse numbers) for two different cases of measuring A and B, corresponding to different imbalances of the parameters of the inductive converter 1. For these cases, rh Gy, where r is the time constant of the circuit. When limiting the formation time of the output voltage by time limit unit 5 to T0gr, the output voltage of the device is for the first example UA, and for the second UB. When the voltage level is limited by block 9 to the UOPT level, the time determined by the number of supply voltage pulses is shortened for the first example to TA, and for the second example to TV.

The numbers of pulses NA - and NB t - character and

0

five

Claims (1)

The change in active resistance of converter 1 is measured, respectively, for the first and second examples (Fig. 3). From FIG. 3, it is clear that TA Tper. A, and Tv Tper in, which corresponds to an increase in speed. Claims of the invention A device for electromagnetic control of objects, according to the author. St. Mg 1427283. characterized in that, in order to increase speed, it is equipped with a time limit unit connected between the integrator output and the measuring unit and a level limit unit by means of which the integrator is connected to the control input of the pulse counter. 72 one V3 1 FIG. 2 Fig.Z