Abstract:
A measuring device for detecting a metal object includes two emission coils configured to produce superimposed magnetic fields, a receiving coil in the region of both magnetic fields, and a control device configured to control the emission coils such that a value of a voltage, which is clock synchronized with alternating voltages and which is induced in the emission coils, is minimized. The control device is configured to detect the metal object when a ratio of the alternating voltages does not correspond to a ratio of distances between the receiving coils and the emission coils.
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 measuring apparatus for detecting a metal object includes two emission coils, a magnetoresistive measuring device, and a control device. The emission coils are configured to produce superimposed magnetic fields. The magnetoresistive measuring device is in the region of both magnetic fields, and is configured to emit an output signal which is dependent on the magnetic field. The control device is configured to supply the emission coils with alternating voltages such that the value of the alternating voltage component of the output signal, which is time synchronized with the alternating voltages, is minimized. The control device is further configured to detect the object when the ratio of the alternating voltages does not correspond to the distances between the magnetoresistive measuring device and the emission coils.
Abstract:
A measuring device for detecting a metal object includes two emission coils configured to produce superimposed magnetic fields, a receiving coil in the region of both magnetic fields, and a control device configured to control the emission coils such that a value of a voltage, which is clock synchronized with alternating voltages and which is induced in the emission coils, is minimized. The control device is configured to detect the metal object when a ratio of the alternating voltages does not correspond to a ratio of distances between the receiving coils and the emission coils.
Abstract:
A locator for detecting an article includes a push-pull measurement bridge configured to actuate a first and a second electromagnetic device in a variable ratio. Depending on the actuation the first electromagnetic device generates an alternating electromagnetic field in the region of the article. The locator further includes a comparator for detecting the article, should the variable ratio differ by more than a predetermined amount from a predetermined ratio.
Abstract:
An ear thermometer with an infrared sensor, a control unit and a power supply unit in a housing has a wireless communication interface. The wireless communication interface is a WLAN or Bluetooth interface for communication with a base station, in which temperature measurement values are displayed and stored.
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 device for detecting a metal object includes an emission coil configured to produce a magnetic field and a compensation network which is connected to the emission coil. A differential voltage is applied between the emission coil and the compensation network. The measuring device also includes a control device configured to supply the emission coil and the compensation network with alternating voltages such that the value of an alternating 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 a ratio of the alternating voltages does not correspond to a ratio of the flows flowing through the emission coils and the compensation network.
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.