RU1824601C - Simulator of magnetic field gradient for calibration testing of equipment for magnetic testing of ferromagnetic sheet materials - Google Patents

Abstract

The invention relates to magnetic measurements and can be used to verify means of magnetic control of sheet ferromagnetic materials. The simulator contains controlled pulse generators, a reversible pulse counter, a memory unit, a current transducer, a measure of the magnetic field gradient, a sheet speed input block, a pulse counter, a control unit, a magnetized section length input block, an adder, a division block, a duration input block magnetizing pulses, the multiplication unit, The simulator has enhanced functionality by simulating the change in time of the gradient of the magnetic field, affecting my tool, taking into account the size of the magnetized portion of the sheet, the speed of movement of the sheet and the duration of the magnetizing pulses 4 silt. (L

Description

The invention relates to the field of magnetic measurements and can be used to metrologically provide means for magnetic control.

The purpose of the invention is to expand the functionality of the device.

Figure 1 presents the functional diagram of the device.

Figure 2 shows an embodiment of a functional block diagram of a memory unit.

Fig. 3 shows an embodiment of a functional diagram of a control unit.

Figure 4 presents the shape of the pulses of the magnetic field generated by the device.

The device consists of a series-connected first controlled pulse generator 1, a reverse counter

(PC) 2 pulses, memory unit 3, including memory 15. digital-to-tax converter 16 and low-pass filter 17, current converter 4 and magnetic field gradient measure 5, series-connected sheet speed input unit 6, second controlled generator 7 pulses, a counter 8 pulses and a control unit 9, the output of which is connected to the control input of a reversible counter 2 pulses, and the second input is connected to the output of a reverse counter 2 pulses, connected in series to the length input unit 10 lag portion, adder 11 and division block 12, the output of which is connected to the control input of the first controlled pulse generator 1, follower00

Yu

Oh Oh

but connected to the magnetization pulse duration input unit 13 and the multiplication unit 14, the output of which is connected to the second input of the adder 11, the output of the sheet speed setting unit 6 being connected to the second inputs of the division unit 12 and the multiplication unit 14.

As the unit 6 for inputting the speed of movement of the sheet, the unit 10 for inputting the length of the magnetized section and the unit 13 for inputting the duration of the magnetizing pulses, potentiometers can be used, for example, from which signals are proportional to the speed of the sheet, the length of the magnetization and the duration magnetizing pulses.

When moving, the magnetized portion of the ferromagnetic sheet passes by the magnetically sensitive elements of the verified means of magnetic control over time

g - + t (1) where I is the length of the magnetized section of the sheet, measured during magnetization in static; v is the speed of the sheet; t is the duration of the magnetizing pulses.

Since the gradient of the magnetic field created by the measure is proportional to the current flowing through it, and its distribution in space is determined by the construction of the measure, to simulate the pulses of the magnetic field affecting the magnetically sensitive elements of the verified means of the magnetic field, it is necessary to form current calibrated in amplitude through the measure windings, the frequency of which is determined by the frequency of the magnetizing pulses (or the distance between the magnetized sections), the duration is determined by with respect to (1), and the shape is determined by the shape of the distribution of the stress gradient of the floor of the magnetized portion measured on the resting sheet (see Fig. 4).

The device operates as follows.

A voltage proportional to the speed v of the sheet moves is supplied from the input unit b of the input speed of the sheet to the input of the second control unit 7 of the pulse generator and to the second inputs of the dividing unit 12 and the multiplying unit 14, and the adder 11 is supplied from the output of the input unit 10 of the length of the magnetized section stress proportional to the length I of the magnetized portion of the sheet, measured in statics. From the block 13 input the duration of the magnetizing pulses to the input of the block multiplication 14 receives the voltage

proportional to the duration t of magnetizing pulses of the verified means of magnetic control. As a result, a signal proportional to v, t appears at the output of multiplication block 14, a signal proportional to (I + v t) at the output of adder 11, and a proportional signal at the output of division block 12

v ±

(I + v -t) t

The first controlled pulse generator 1 generates pulses Ui with a frequency

2N fl -, where N is the capacity of the reverse

counter 2, corresponding to the number of values of the voltage gradient of the field of the magnetized portion recorded in the memory unit 3. The output pulses of the first controlled pulse generator 1 are input to the input of the reversible counter 2 pulses. The output code of the counter, which varies in time with the frequency fi, is supplied to the address inputs of the memory unit 3, which stores information on the distribution of the voltage gradient of the field of the magnetized section, measured on a resting sheet. The output information taken from the memory unit 3 is converted by a current converter 4 into a current value that passes through the windings of measure 5 of the magnetic field gradient and creates a magnetic field in its working areas with a corresponding gradient. In view of the fact that the distribution of the stress gradient of the field of the magnetized section of the sheet is symmetrical about its center, only half of the magnetized section is stored in the memory unit 3; from the edge to the center (see figure 4). The complete pulse is generated by sequentially sorting the addresses of the memory block 3, first in the forward and then in the opposite direction. This mode is achieved as follows. When during the direct counting of the reversible counter 2 pulses it is completely filled (i.e., all addresses of the memory block 3 have been enumerated), the control unit 9 is activated (trigger 18 from the signals of the EXCLUSIVE OR 20, AND 21 circuits). switching the reverse counter 2 to the position of the countdown. Enumeration of the addresses of the memory unit 3 begins in the reverse direction. When the contents of the reverse counter 2 reach a zero value, it is blocked by the signal from the control unit 9 (from the output of the trigger 19 in Fig. 3). Impulse formation is complete. The next pulse shaping cycle starts after

counter overflow 8 pulses. By the overflow signal of the pulse counter 8, the control unit 9 unlocks the reversible pulse counter 2 and the formation process is repeated. The amplitude of the current pulse in the measure 5 of the magnetic field gradient is determined by the conversion coefficient of the current transducer 4.

 Thus, by sequentially sorting the addresses of the memory unit 3 with a frequency f 1 and converting its output information into the amount of current passing through measure 5 of the magnetic field gradient, a magnetic field pulse is generated, the magnitude and shape of which in time is similar to the shape of the magnetic gradient the floor (acting on the magnetically sensitive elements of the verifiable control means) from the locally moving magnetized sheet on both sides, taking into account the size of the magnetized area in static (take into account the magnetization parameters ayuschego device), the traveling speed of the sheet (transit time is taken into account by the magnetized portion and void magnitochuv- elements) and the duration of pulse magnetizing (smearing magnetized portion is taken into account during magnetization in motion). The repetition rate (for a given distance L between the control points) is determined by the speed of the sheet.

Claims (1)

SUMMARY OF THE INVENTION A magnetic field gradient simulator for verifying magnetic control means for sheet ferromagnetic materials, comprising a first controllable pulse generator, a pulse counter, a measure of the magnetic field gradient and a control unit, characterized in that in order to expand the functionality, a reversible pulse counter, a memory unit and a current converter connected between the first controlled pulse generator and the measure of the magnetic field gradient, connected in series to the sheet speed input unit and the second controlled pulse generator connected through a pulse counter with the first input of the control unit, the output and second input of which are connected respectively to the control input and the output of the reverse counter serially connected magnetization section extension input unit, an adder and a division unit, the output of which is connected to the control input of the first controlled pulse generator, serially connected magnetization pulse duration input unit and a multiplication unit, the output of which is connected to the second adder input, and the output of the unit the input speed of the sheet is connected to the second inputs of the division unit and the multiplication unit. FIG. I PC alarm signal J  /, 2 / v Editor FIG. 4 Compiled by V. Matyuk Tehred M. Morgenthal PLANE fox Corrector N, King