SU676957A1 - Automatic device for measuring maximum specific power of magnetic materials - Google Patents

Description

the resident is connected to the outputs of both sensors, the third input is connected to the first output of the combined magnetization unit, and the first output is connected to the input of a digital reading device, as well as an incompletely closed magnetic system and linear generators of decreasing and increasing current connected to the inputs of the combined magnetization unit, the second output which is connected with the first input of the control trigger, and the second input of the last - with the second output of the digital tracking system, a block for fixing the incompleteness of the measurement process is introduced, connected in a form of successively connected matching logic element, control unit and polarity switch, as well as generator switch and current presence indicator, the input of which is connected to the third output of the combined magnetization unit, and outputs to the second input of the polarity switch and the first input of the logic element a match, the second input of which is connected with the second output of the digital tracking system, its third input connected with the third input of the matching logic element, and the output block The control is connected to the first input of the generator switch, the second input of which is connected to the control trigger output, the outputs of the generator switch are connected to the inputs of the linear rise and fall generators, and the output of the polarity switch is connected to the input of an incompletely closed magnetic system.

The drawing shows a block diagram of the device.

The device contains a controlled power supply 1, a key 2, a zero voltage sensor 3, a multiplying device 4, an induction sensor 5, a digital tracking system 6, a digital reading device 7, a matching logic element 8, a control unit 9, a control trigger 10, a switch 11 generators, a current presence indicator 12, a polarity switch 13, a linear current generator 14, a linear current decrease generator 15, a combined magnetization unit 16, an incompletely closed magnetic system 17.

The device works as follows.

At the beginning of the measurement process, a start signal is applied to the combined magnetization unit 16, which creates in the gap of an incompletely closed magnetic system 17 a magnetizing field formed by a constant current impulse current applied to it. At the same time, the signal is applied to the logical, coincidence element 8, the driving generator switch 11 and the polarity switch 13 to the initial state, and to the digital tracking system, which also returns to the initial state. At the moment of termination of the magnetizing pulse, the combined magnetization unit 16 receives a signal at the input of the control trigger 10, which is transferred to another stable state, starts the current decreasing linear generator 15 and opens the key 2. In this case, the linearly varying

the voltage from the output of the linear generator to the input of the combined magnetization unit 16, resulting in a smooth reduction of the constant magnetizing field in the gap of the magnetic system 17.

When the key 2 is unlocked, the voltage of the controlled power supply 1 is supplied to the sensors 3 and 5 of the field and induction voltage and the digital tracking system 6. To obtain a signal proportional to the magnetic energy, the output attributes of the sensors 3 and 5 are multiplied using the multiplying device 4. Received after multiplying the signal is fed to the input of the digital tracking system

6, which measures it and represents the result of the measurement in digital form on a digital reading device 7. Moreover, the digital tracking system starts counting the measured value of the linch since

equal to the intensity of the field zero H 0, i.e. when moving to the second quadrant in the rectangular coordinate system. As the magnetizing field decreases, there is a continuous measurement of magnetic energy.

The growth of the readings of the digital reading device 7 continues until the magnitude of the magnetic energy reaches its maximum value. After that, the voltage at the output of the multiplying

device 4 begins to decrease, the digital tracking system 6 stops counting and outputs a zero signal to the input of the logic element 8 coincidence and the control trigger W, and on the digital readout

The device 7 is fixed a value corresponding to the maximum magnetic energy. The trigger trigger returns to its original state, which locks key 2 and removes the power supply.

the voltage from sensors 3 and 5 and digital tracking system 6, as well as the control potential is removed from the input of the linear oscillator 15 of descending order. The latter leads to the fact that the current in the coils of the magnetic

system 17 is turned off and reduced to zero. The matching circuit 8 does not work in this case, since the process of measuring magnetic energy ends in the presence of a magnetizing constant

the field in the magnetic system 17, as a result of which at the second input of the logic element coincidence 8 there is a signal different from zero.

When testing samples, the operating point

which lies on the demagnetization curve

above the point of maximum energy, its value in the process of decreasing the magnetisation, its sex is not reached. In this case, after reducing the magnetizing field to zero in the magnetic system, it is necessary to create a smoothly increasing magnetizing field. For this, a measurement incomplete fixation unit is used, circled by a dotted line in the drawing, which is triggered if the measurement process does not end. At the same time, both inputs of the matching element 8 receive zero signals, as a result of which the latter operates and sends a signal to the control unit 9, which switches the polarity of the current in the coils of the magnetic system, connects to the output of the control trigger 10 a linear increase current generator 14 and restarts digital trace system.

The use of the proposed scheme for measuring the maximum specific magnetic energy makes it possible in devices with an incompletely closed magnetic system to significantly expand the range of measured permanent magnets. Thus, in devices, it will be possible to measure permanent magnets with both small and large relative lengths. In addition, the use of the proposed invention will improve the accuracy of the above devices.

Claims (2)

1. Technical description of the installation U-5022. 2. USSR author's certificate number 386356, cl. G OIR 33/12, 1973.