Abstract:
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.
Abstract:
A measuring apparatus for detecting a dielectric object comprises a potential probe for determining an electric potential in an electric field, a first capacitance device, a second capacitance device, and a control device configured to supply alternating voltages to the first and the second capacitance devices. The control device is configured to amplify the alternating voltages in opposite directions to one another in order to minimize the magnitude of an AC voltage component, which is clock-synchronous with the alternating voltages, of a voltage which is recorded by means of the potential probe. The dielectric object is detected when a ratio of the alternating voltages does not correspond to a ratio of (i) a first distance of the potential probe from the first capacitance device to (ii) a second distance of the potential probe from the second capacitance device.
Abstract:
A device for detecting an object includes a coil for generating a magnetic field in the region of the coil, a first electrode for generating an electrical field in the region of the electrode, and an evaluating device for detecting the object on the basis of an influence of the magnetic field or the electrical field. The device also includes a separating device configured to suppress a current flow through the coil so as to use the coil as an electrode.
Abstract:
The disclosure relates to a method for localizing objects enclosed in a medium in which a measurement signal correlated to the enclosed object is generated and is used to produce a signal for transmission to a user. The signal allows at least a distinction between a first state “Object detected” and at least one second state “no object detected.” The disclosure proposes that a third state “Object close by” be provided. Furthermore, the disclosure relates to a measuring device, particularly a hand-held locating device, for carrying out the method according to the disclosure.
Abstract:
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.
Abstract:
A locator for capacitively sensing an object includes a transmission electrode to which an excitation signal can be applied, a reception electrode, a sensing region in the region of the transmission electrode and the reception electrode, and a measuring device for sensing a capacitance between the transmission electrode and the reception electrode. The locator further includes a processing device for determining the presence of the object in the sensing region if the sensed capacitance differs from a reference capacitance, and a screening electrode that is arranged in the region of the transmission electrode and the reception electrode. The screening electrode is connected to a potential so as to reduce the base capacitance between the transmission electrode and the reception electrode.
Abstract:
A locator for capacitively sensing an object includes a transmission electrode to which an excitation signal can be applied, a reception electrode, a sensing region in the region of the transmission electrode and the reception electrode, and a measuring device for sensing a capacitance between the transmission electrode and the reception electrode. The locator further includes a processing device for determining the presence of the object in the sensing region if the sensed capacitance differs from a reference capacitance, and a screening electrode that is arranged in the region of the transmission electrode and the reception electrode. The screening electrode is connected to a potential so as to reduce the base capacitance between the transmission electrode and the reception electrode.
Abstract:
A sensor apparatus, in particular a metal sensor, has at least two coils and a magnetic field sensor. The arrangement of coils and magnetic sensor with respect to one another and/or the number of coil turns and/or the winding sense of the coils and/or the coil current is/are selected such that the magnetic field generated by the coils approximately disappears at the location of the magnetic field sensor. A method for detecting objects, in particular a method for finding metal objects, uses at least two coils and a magnetic field sensor, particularly an AMR, GMR or Hall sensor. The arrangement of the coils and the magnetic sensor with respect to one another and/or the number of coil turns and/or the winding sense of the coils and/or the coil current is/are selected such that the magnetic field generated by the coils approximately disappears at the location of the magnetic field sensor.
Abstract:
A measuring apparatus for detecting a dielectric object comprises a potential probe for determining an electric potential in an electric field, a first capacitance device, a second capacitance device, and a control device configured to supply alternating voltages to the first and the second capacitance devices. The control device is configured to amplify the alternating voltages in opposite directions to one another in order to minimize the magnitude of an AC voltage component, which is clock-synchronous with the alternating voltages, of a voltage which is recorded by means of the potential probe. The dielectric object is detected when a ratio of the alternating voltages does not correspond to a ratio of (i) a first distance of the potential probe from the first capacitance device to (ii) a second distance of the potential probe from the second capacitance device.
Abstract:
A measuring device configured to detect a metal object includes two emission coils configured to produce superimposed magnetic fields. The measuring device also includes a device configured to determine a differential voltage between the emission coils. The measuring device further includes a control device configured to supply the emission coils with alternating voltages such that the value of an AC voltage component of the differential voltage, which is time synchronized with the alternating voltage, is minimized. The control device is configured to detect the metal object when the ratio of the alternating voltages does not correspond to the ratio of the impedances of the emission coils when the metal object is not there.