Robert Boschgmbh

Markus Hahl

Andrej Albrecht

Tobias Zibold

Oliver Grossmann

Christoph Wieland

Juergen Winterhalter

A sensor for locating metallic or magnetizable objects comprises two emission coils and a receiving coil which are inductively interconnected. A method for determining the influence of temperature on the sensor includes supplying a first pair of predetermined alternating currents to the emitter coils, and simultaneously sampling current flows which pass through the emitter coils and a first current of the receiver coil. Subsequently, the method includes supplying a second pair of predetermined alternating currents to the emitter coils, and simultaneously sampling current flows which pass through the emitter coils and a second current of the receiver coil. The method further includes determining coupling factors between the emitter coils and the receiver coils based on the determined current flows and voltages, and determining the object based on the coupling factors.

Object locater and method for locating a metallic and/or magnetizable object

A metal sensor includes a primary coil, a compensation coil, a first additional coil, and a magnetic field sensor. The first additional coil is configured to be excited without the primary coil and the compensation coil being excited.

Metal sensor

A measuring device for detecting a conductor that carries alternating voltage, includes a voltage source configured to produce two phase-shifted alternating voltages, two complex impedance elements having first connections, which are connected to the alternating voltages, and second connections, which are connected to each other and to which a differential voltage is applied, and a control device configured to control the alternating voltages in such a way that a component of the differential voltage synchronous with the alternating voltages is minimized in magnitude. The control device is configured to detect the conductor if a ratio of the alternating voltages does not correspond to a ratio of the complex impedance elements in the absence of the conductor. The second complex impedance element is changeable with a control voltage. A probe is configured to provide the control voltage as a function of an alternating electromagnetic field induced by the conductor.

Cable detector

A device for detecting a dielectric object includes a first electrode and a second electrode. A first unit is configured to determine a first capacitance that exists between the first electrode and a common reference point and that is influenced by the object. A second unit is configured to determine a second capacitance that exists between the second electrode and the reference point and that is influenced by the object. The device further includes a control unit for actuating the first and second units and an evaluating unit that is configured to detect the object when the determined capacitances differ by more than a predetermined amount. The control unit is configured to actuate the units in such a manner that the capacitance determinations are carried out in succession. A switching unit is provided so as to electrically connect the electrode of the respective non-actuated unit to the common reference point.

Detecting a dielectric article

A measuring apparatus for sensing metal articles, comprises a transmission coil for producing a magnetic field, two reception coils, which are oriented relative to one another, and electrically connected to one another, in the region of the magnetic field such that a resulting received voltage on the reception coils is zero when the magnetic field acts on both reception coils in the same way, a control device configured to supply the transmission coil with an alternating transmission voltage, and a determination device configured to determine the metal article on the basis of the received voltage. In this arrangement, the control device is further configured to control RMS value for the transmission voltage such that the received voltage remains below a predetermined threshold value.

Growing community of inventors

Korntal-Muenchingen, Germany

Markus Hahl