SU879278A1

SU879278A1 - Device for measuring dielectric material thickness

Info

Publication number: SU879278A1
Application number: SU792713026A
Authority: SU
Inventors: Валентин Андреевич Синицкий; Юрий Александрович Резников; Лев Моисеевич Гугелев; Валерий Михайлович Федоров
Original assignee: Предприятие П/Я А-1944
Priority date: 1979-01-11
Filing date: 1979-01-11
Publication date: 1981-11-07

Description

Изобретение относится к измерительной технике и может быть использовано в любой отрасли машиностроения для измерения толщины диэлектрических материалов с использованием токопроводящей подложки. ⁵ The invention relates to measuring equipment and can be used in any industry for measuring the thickness of dielectric materials using a conductive substrate. ⁵

Известно устройство для измерения толщины диэлектрических материалов, содержащее электромагнитный преобразователь и подсоединенные к нему генератор й измерительный канал ζΐ J.A device for measuring the thickness of dielectric materials is known, comprising an electromagnetic transducer and a generator and measuring channel ζΐ J. connected to it.

Недостатками известного устройства являются.ограниченный верхний предел измеряемых толщин и малая чув-_J5ствительность к изменению больших толщин .Disadvantages of the known device yavlyayutsya.ogranichenny upper limit of measurable thicknesses and sen- _J5 ity of small to large thickness change.

Цель изобретения - повышение чувствительности и расширение диапазона измерений. _Μ The purpose of the invention is to increase sensitivity and expand the measurement range. _Μ

Поставленная цель достигается тем, что преобразователь выполнен в виде двух соосных, с зазором между витками , цилиндрической ч плоской спиралей из токопроводящего материала, причем наружный виток плоской спирали является продолжением цилиндрической.This goal is achieved in that the transducer is made in the form of two coaxial, with a gap between the turns, cylindrical h flat spirals of conductive material, and the outer turn of the flat spiral is a continuation of the cylindrical.

На чертеже представлена блок-схема устройства.The drawing shows a block diagram of a device.

Устройство для измерения толщины диэлектрических .материалов содержит электромагнитный преобразователь, выполненный в виде двух соосных, с зазором между витками., цилиндрической и плоской спиралей 1 и 2 из токопроводящего материала. Наружный виток плоской спирали 2 является продолжением цилиндрической спиралиA device for measuring the thickness of dielectric materials contains an electromagnetic transducer made in the form of two coaxial, with a gap between the turns., A cylindrical and flat spirals 1 and 2 of conductive material. The outer turn of a flat spiral 2 is a continuation of a cylindrical spiral

1. Обе последовательно соединенные спирали от центра плоской спирали 2 и конца цилиндрической спирали, также выходящего из центра катушки, подсоединены к конденсатору 3 и образуют с ним колебательный контур, который через усилитель 4 и буферный каскад 5 соединены с генератором 6 переменного напряжения высокой частоты. Колебательный контур соеди31. Both serially connected spirals from the center of the flat spiral 2 and the end of the cylindrical spiral, also emerging from the center of the coil, are connected to the capacitor 3 and form an oscillating circuit with it, which through the amplifier 4 and the buffer stage 5 are connected to the high-frequency alternating voltage generator 6. Oscillating circuit of the connection3

879278 нен через конденсатор 7 с измеритель·? ным каналом 8, к выходу которого подключен индикатор 9.879278 nen via capacitor 7 s meter ·? channel 8, the output of which is connected indicator 9.

Работает устройство следующим образом.The device operates as follows.

Преобразователь накладывают плос' кой спиралью 2 на контролируемый материал с токопроводящим основанием или с подложкой из токопроводящего • материала, наприйер, фольги, при этом добротность катушек преобразователя самого колебательного контура, а, следовательноj и выходной сигнал устройства изменяются. По индикатору 9 осуществляется отсчет толщины контролируемого изделия. При увеличении толщины контролируемого диэлектрического материала происходит увеличение добротности электромагнитного преоб10 ния на электромагнитное поле цилиндрической спирали 1.The transducer is imposed with a flat spiral 2 on the controlled material with a conductive base or with a substrate of conductive • material, for example, foil, while the quality factor of the transducer coils of the oscillating circuit itself, and therefore the output signal of the device, are changed. Indicator 9 reads the thickness of the controlled product. With an increase in the thickness of the controlled dielectric material, an increase in the quality factor of the electromagnetic transition to the electromagnetic field of the cylindrical spiral 1 occurs.

Поскольку индуктивность преобразователя увеличена по сравнению с известными устройствами за счет цилиндрической спирали 1, то рабочая частота контура может быть понижена, что уменьшает влияние диэлектрических потерь разных материалов, а также разных участков одного и того же материала на выходной сигнал преобразователя. Это способствует повышению точности измерений, так как уменьшается влияние одного из мешающих факторов. Предлагаемое устройство позволяет измерять толщины диэлектрических материалов до 90-100 мм.Since the inductance of the converter is increased compared to the known devices due to the cylindrical spiral 1, the working frequency of the circuit can be reduced, which reduces the effect of the dielectric loss of different materials, as well as different sections of the same material on the output signal of the converter. This helps to improve the accuracy of measurements, since the influence of one of the interfering factors is reduced. The proposed device allows you to measure the thickness of dielectric materials up to 90-100 mm

Таким образом, указанное выполнение преобразователя позволяет резко разователя и, соответственно, увеличение сигнала, снимаемого с колебательного контура.Thus, the specified implementation of the Converter allows you to sharply develop and, accordingly, an increase in the signal taken from the oscillatory circuit.

Поскольку максимальная величина измеряемой толщины диэлектрического материала зависит от расстояния, на которое распространяется электромагнитное поле преобразователя с заданной величиной напряженности, вызывающей реакцию токопроводящей подложки, устройство позволяет расширить диапазон измеряемых толщин путем создания электромагнитного поля большей мощности без увеличения диаметра преобразования. Необходимую добавочную мощность электромагнитного поля преобразователя₍ добавляемую к мощности плоской спирали 2, получают за счет мощности цилиндрической спирали 1. Поскольку оси спиралей совпадают, а витки направлены в одну сторону, электромагнитные поля, создаваемые ими, суммируются.Since the maximum value of the measured thickness of the dielectric material depends on the distance over which the electromagnetic field of the transducer extends with a given value of the tension causing the reaction of the conductive substrate, the device allows you to expand the range of measured thicknesses by creating an electromagnetic field of greater power without increasing the diameter of the conversion. The necessary additional power of the electromagnetic field of the converter ₍ added to the power of a flat spiral 2, is obtained due to the power of the cylindrical spiral 1. Since the axes of the spirals coincide, and the turns are directed in one direction, the electromagnetic fields created by them are summed up.

Токопроводящее сечение цилиндрической спирали 1 чрезвычайно мало, поэтому уменьшение электромагнитного поля плоской спирали 2 за счет экранирующего действия нижнего витка цилиндрической спирали 1 не сказывается на чувствительности преобразователя. В свою очередь небольшая токопроводящая площадь плоской спирали 2 не оказывает существенного влияThe conductive cross section of the cylindrical spiral 1 is extremely small, therefore, the decrease in the electromagnetic field of the flat spiral 2 due to the shielding effect of the lower turn of the cylindrical spiral 1 does not affect the sensitivity of the transducer. In turn, the small conductive area of the flat spiral 2 does not have a significant effect

2Q увеличить мощность получаемого электромагнитного поля без увеличения диаметра преобразователя, что увеличивает диапазон измеряемых толщин.2Q increase the power of the resulting electromagnetic field without increasing the diameter of the transducer, which increases the range of measured thicknesses.

Сопутствующее этому увеличение ин25 дуктивности преобразователя позволяет понизить его рабочую частоту, что увеличивает чувствительность преобразователя к изменению больших толщин диэлектрического материала вследствие ₃₀ уменьшения влияния на добротность пре· образователя диэлектрических потерь при более низкой рабочей частоте.The concomitant increase in the inductance of the converter makes it possible to lower its operating frequency, which increases the sensitivity of the converter to changes in large thicknesses of the dielectric material due to a ₃₀ decrease in the effect of the dielectric loss factor on the Q factor at a lower working frequency.

Claims

The invention relates to a measurement technique and can be used in any industry of mechanical engineering for measuring the thickness of dielectric materials using a conductive substrate. A device for measuring the thickness of dielectric materials is known, comprising an electromagnetic transducer and a generator and measuring channel 1 | connected to it. The disadvantages of the known device are the limited upper limit of the measured thicknesses and the low sensitivity to changes in large areas. The purpose of the invention is to increase the sensitivity and the expansion of the measurement range. The goal is achieved by the fact that the transducer is made in the form of two coaxially, with a gap between the turns of a cylindrical flat spiral OZ conductive material, and the outer turn of the flat spiral is a continuation of the cylindrical. The drawing shows the block diagram of the device. The device for measuring the thickness of dielectric materials contains an electromagnetic transducer, made in the form of two coaxially, with a gap between the turns, a cylindrical and flat coils 1 and 2 of conductive material. The outer turn of the flat helix 2 is a continuation of the cylindrical helix 1. Both series-connected helixes from the center of the flat helix 2 and the end of the cylindrical helix also extending from the center of the coil are connected to the capacitor 3 and form an oscillating circuit with it, through the amplifier 4 and the buffer cascade 5 is connected to a high frequency alternating voltage generator 6. The oscillatory circuit is connected through a capacitor 7 to measuring channel 8, to the output of which indicator 9 is connected. The device operates as follows. The transducer is applied with a flat coil 2 on the material under test with a conductive base or with a substrate made of conductive material, such as foils, while the quality factor of the transducer coils of the oscillating circuit itself and, consequently, the output signal of the device change. Indicator 9 is used to measure the thickness of the test item. With an increase in the thickness of the controlled dielectric material, an increase in the quality factor of the electromagnetic converter and, accordingly, an increase in the signal removed from the oscillatory circuit. Since the maximum measured thickness of the dielectric material depends on the distance over which the electromagnetic field of the transducer extends with a predetermined amount of tension that induces the reaction of the conductive substrate, the device allows the range of measured thicknesses to be expanded by creating an electromagnetic field of greater power without increasing diameter conversion. Required additional power of the electromagnetic field converter | added to the power of the flat helix 2, is obtained due to the power of the cylindrical helix 1. Since the axes of the helixes coincide, and the coils are directed along one direction, Y, are summed, the l, created by the conductive section of the cylindrical helix 1, are extremely small. Therefore, the reduction of the electromagnetic field of the flat helix 2 due to the shielding effect of the lower coil of the cylindrical helix 1 does not affect the sensitivity of the transforming body. In turn, the small conductive surface of the flat helix 2 does not significantly affect the electromagnetic field of the cylindrical helix 1. As the inductance of the converter is increased compared to known devices due to the cylindrical helix, the operating frequency of the circuit can be reduced, which reduces the effect dielectric losses of different materials, as well as different sections of the same material on the output signal of the converter. This contributes to an increase in measurement accuracy, since the influence of one of the interfering factors is reduced. The proposed device allows measuring the thickness of dielectric materials up to 90-100 mm. Thus, the above implementation of the converter allows a sharp increase in the power of the resulting electromagnetic field without increasing the diameter of the converter, which increases the range of measured thicknesses. The concomitant increase in the inductance of the converter reduces its operating frequency, which increases the sensitivity of the converter to changes in large thicknesses of the dielectric material due to a decrease in the effect on the quality factor of the dielectric converter at a lower operating frequency. An apparatus for measuring the thickness of dielectric materials, comprising an electromagnetic transducer and a generator and a measuring channel connected to it, characterized in that, in order to increase sensitivity and extend the measurement range, the transducer is completed in the form of two coaxially, with a gap between the coils, cylindrical and flat spirals of conductive material, and the outer turn of the flat spiral is pro-. due-cylindrical. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 151034, cl. G 01 B 7/06, 1962 (prototype).

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