Robert Boschgmbh

Hansjoerg Hachtel

Klaus Dobler

Josef Weber

Reinhard Dimke

Stefan Meyer

Richard Blattert

Thomas Moser

Jens Stefan Schneider

Armin Witzig

Franz Auf Der Heide

With a method for the contactless determination of a thickness of a layer () made of electrically-conductive material of a component (), a sensor composed of a coil form () and a coil () is positioned in the vicinity of the component () to be measured. The method is based on a combination of the principles of induction and eddy current. The thickness of the layer () is determined using a plurality of measuring and evaluation steps in which the coil () is acted upon with a first alternating current frequency f and its inductance and resistance values are evaluated. The distance between the coil form () and, therefore, the coil (), and the component () is derived from the resistance value R of the coil () acted upon with alternating current frequency f.

Method for the contactless determination of a layer thickness via resistance and inductance measurement of a sensor oil

With a method for the contactless determination of a thickness of a layer () made of electrically-conductive material of a component (), a sensor composed of a coil form () and a coil () is positioned in the vicinity of the component () to be measured. The method is based on a combination of the principles of induction and eddy current. The thickness of the layer () is determined using a plurality of measuring and evaluation steps in which the coil () is acted upon with a first alternating current frequency fand a second alternating current frequency f, and its change in inductance is evaluated. The distance between the coil form () and, therefore, the coil (), and the component () is derived from the inductance value of the coil () acted upon with the second alternating current frequency f

Method for the contactless determination of a thickness of a layer made of electrically-conductive material

A method for defining the characteristics of metal electrodes of ceramic sensor elements, where the metal electrodes are deposited as layers and subjected to a subsequent annealing process. The aim is to provide a non-destructive, simple and economical method, capable of being automated, for performing an acceptance test in a specimen-specific manner on the sensor element. In the case of the test procedure proposed here, the quantity and distribution of gold deposited so as to be inaccessible in the protective layer, are indirectly determined. This is done by measuring the layer thickness during manufacturing of an electrode, in a before/after comparison, with the aid of an eddy-current measuring process where the electrode is placed in the magnetic circuit of a coil that is traversed by the flow of a high-frequency a.c. current, and the resulting ostensible inductance of the coil is measured using an LCR measuring unit. The coil can be wired as a resonant circuit with the aid of a capacitor.

Method for defining the characteristics of metal electrodes of ceramic sensor elements

In a method for determining a thickness of a layer of electromagnetically conductive material, the measurement errors resulting from different quality of the basic material are eliminated. For each basic material, one dimensionless characteristic value (K) is ascertained. With the aid of a characteristic calibration curve, each characteristic value (K) can be assigned a correction factor (F), with which the measured value of the layer thickness (D ) can be converted into a real value of the layer thickness (D). Different electrical and magnetic properties, dictated by the different quality of the basic material, can thus be largely eliminated.

Method for determining the thickness of a layer of electrically conductive material

A process for determining a thickness of a layer of electrically conductive material, any measurement errors are converted into dimensionless norm values with the aid of a normalization process. In this conversion, measurement errors, for example due to temperature drift and different electrical and magnetic properties of the base material of the carrying body can be largely eliminated. These norm values are converted into layer thickness values with the aid of a calibration curve.

Process for determining the thickness of a layer of electroconductive material deposited on a body

A measuring arrangement for contactless determination of rotation angle has two bodies arranged movably relative to one another, sensor coils with inductive and alternating current resistance values variable by a relative change of size of portions of the bodies associated with the coils. The bodies include a first body divided into a plurality of regions corresponding to the coils and disassociated with a respective one of the coils. The regions are offset relative to one another in an axial direction and also offset in a radial direction in correspondence with the number of the regions by a certain angle. The coils are formed as wire coils.

Measuring arrangement having axially and radially offset sensor coils

A measuring device for contactless control of a design of structural elements composed of an electrically conductive material comprises at least one coil through which an alternating current flows and whose measuring voltage is influenced by a structural element, and electronic evaluating unit arranged to compare the measuring voltage of the coil influenced by the structural element with a nominal value, the coil being formed as a cylindrical coil.

Device for determining geometric parameters of a structural element

A measuring device for contactless determination of condition of screw shaped structural elements comprises two oppositely located coils supplied with an alternating current spaced from one another so that an electrically conductive structural element passes therebetween, and transporting elements formed so that the structural element is guided on an edge so that a distance between the structural element and at least one of the coils remains constant during a measuring process.

Device having oppositely spaced coils for determining a shape of screw

A device for contactless measurement of a rotational angle of a rotating part that is rotatable via a rotating shaft. The device includes a cylindrical coil carrier with sensor coils and a tubular body of electrically conductive material that is firmly attached to the rotating shaft and which surrounds the coil carrier with radial play and has an electrically non-conductive zone extending circumferentially in the vicinity of the sensor coils. For the sake of an easy-to-assemble structure, the tubular body is slipped onto a face end of the rotating shaft in a form-fitting manner and the tubular body is surrounded with radial play by a housing cup, from the bottom of which the coil carrier, which is integral with it, coaxially protrudes. The housing cup is joined in a floating manner to a housing that receives the rotating part.

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Weissach, Germany

Hansjoerg Hachtel