Class / Patent application number | Description | Number of patent applications / Date published |
324681000 | With frequency signal response, change or processing circuit | 50 |
20090066346 | DETECTION CIRCUIT DEVICE AND METHOD FOR DETECTING THE PRESENCE OF AN OBJECT IN THE VICINITY OF A MOTOR VEHICLE - The invention relates to a circuit device and a method for detecting the presence of an object in the vicinity of a motor vehicle. The aim of the invention is to provide solutions which allow monitoring the vicinity of a motor vehicle with regard to the presence of an object. In particular, the aim of the invention is to provide solutions which allow detecting the approach of human body parts to danger-relevant structures, such as for example soft top devices, window openings, door openings and trunk lids, and taking the appropriate safety measures. According to the invention, this problem is solved by a motor vehicle that comprises a detection circuit with a first electrode system, a second electrode system and an alternative current generator for generating a potential difference between the two electrode systems, the first electrode system being arranged in the lower region of the vehicle for inputting the shift current events in the region supporting the vehicle. The detection circuit further comprises an evaluation device by means of which a feedback of the shift current events in the second electrode system is determined via the object to be detected. | 03-12-2009 |
20090096468 | HEAD REST DEVICE FOR VEHICLE - When moving a head rest front portion in a full-open position direction, an ECU determines that the head rest front portion comes close to an occupant head portion on the basis of a detection result of an electrostatic capacitance sensor so as to stop the head rest front portion, and determines that the head rest front portion comes close to the occupant head portion on the basis of an absolute capacitance change with respect to a reference electrostatic capacitance value of the electrostatic capacitance sensor. Alternatively, the ECU determines that the head rest front portion comes close to the occupant head portion on the basis of a change amount of the electrostatic capacitance value of the electrostatic capacitance sensor. | 04-16-2009 |
20090153151 | Obstacle Detection System and Obstacle Detection Method Thereof - An obstacle detection system includes a static capacitance detection module including a sensor strip for detecting a static capacitance, an RF oscillator connected to the sensor strip, a phase lock loop section for maintaining the oscillation frequency of the RF oscillator to a selected value and a first MCU for controlling the operation of the phase lock loop section, a control module including a second MCU for remotely controlling the first MCU of the static capacitance detection module and a transmission line for connecting the static capacitance detection module and the control module and transmitting the information acquired by the first MCU so as to be transmitted to the control module, a control signal to be transmitted from the second MCU to the first MCU and drive power of the static capacitance detection module. | 06-18-2009 |
20090243633 | Capacitance Sensor - A capacitance sensor, having at least one electrode is disclosed. A frequency spread signal generation circuit is coupled to the at least one electrode to apply a frequency spread signal based on a spread sequence. A periodic signal with a frequency is coupled to the at least one electrode. A frequency controller is coupled to the frequency spread signal generation circuit to vary the frequency of the periodic signal. A receiver circuit is coupled to the at least one or a further electrode to receive a version of the frequency spread signal which depends on a capacitance applied to the at least one electrode. An evaluation circuit is coupled to the receiver circuit to determine a capacitance value based on the received, dependent version of the frequency spread signal. | 10-01-2009 |
20090295411 | Occupant Detection System and Method for Calibrating - A method includes measuring a first frequency response of an electrode at a first frequency across a range of environmental conditions, measuring a second frequency response of the electrode at a second frequency across the range of environmental conditions, and comparing the first and second frequency responses measured to define a data set representing an effect of the environmental conditions. An occupant detection system includes an electrode and a detector circuit. The detector circuit is configured to measure an actual frequency response of the electrode and compare the actual frequency response to the data set to determine the effect of the current environmental condition. | 12-03-2009 |
20090295412 | Occupant Detector with Electronic Interference Compensation - A occupant detection system includes an electronic device in communication with a sensor. The system detects an occupant by way of measuring an impedance of an electric field emitted by the sensor. The electronic device is configured to acquire data values from an output signal of the sensor, and reduce the effect of transient electrical interference on the acquired data values and adapt for sustained electrical interference on the acquired data values. A method includes acquiring a new data value, determining whether the new data value represents transient interference, and capturing the new data value if the new data value is free of transient interference and rejecting the new data value if the new data value represents transient interference. | 12-03-2009 |
20100156441 | Capacitive divider device, voltage sensor, trip device module and electrical protection apparatus provided with such a device - A multilayer capacitive divider comprising a first and second main electrode formed on the same level to apply an input voltage, and a common electrode formed on another level to supply an attenuated voltage, said device comprising at least a first auxiliary electrode formed on yet another level, said electrodes being arranged so as to form capacitive units, said auxiliary electrode extending towards a side of said device towards which the second main electrode is arranged so as to connect said auxiliary electrode to the second main electrode by means of a linear conductor. | 06-24-2010 |
20100156442 | PARAMETER EXTRACTION USING RADIO FREQUENCY SIGNALS - A set of parameters of an evaluation structure are extracted by applying a radio frequency (RF) signal through a first capacitive contact and a second capacitive contact to the evaluation structure. Measurement data corresponding to an impedance of the evaluation structure is acquired while the RF signal is applied, and the set of parameters are extracted from the measurement data. In an embodiment, multiple pairs of capacitive contacts can be utilized to acquire measurement data. Each pair of capacitive contacts can be separated by a channel having a unique spacing. | 06-24-2010 |
20100225336 | Object proximity detector and object position detector - The present invention offers an object proximity detector and object position detector. The variation of frequency of an oscillator is used to detect the proximity of an object to a sensor plate. The dependence of the sensitivity of the detector on the area of the sensor plate is reduced by conducting the sensor plate to two capacitors in series. The conducting wire of the sensor plate can be flexible without causing error detection. In the sensor element of the sensor oscillator, a resistor is connected at one terminal of the sensor plate to form a high pass filter. A resistor and a capacitor are added to the sensor oscillator to form a low pass filter. The high pass filter is used to reduce the low frequency electromagnetic interference. The low pass filter is used to reduce the high frequency electromagnetic interference. | 09-09-2010 |
20100289506 | CAPACITIVE SENSOR AND PROXIMITY DETECTOR USING IT - A capacitive sensor may be used as a proximity detector in an obstruction warning system for road vehicles, e.g. for use when the vehicle is reversing. A digital signal processor | 11-18-2010 |
20100321042 | CONFIGURABLE PSRO STRUCTURE FOR MEASURING FREQUENCY DEPENDENT CAPACITIVE LOADS - A configurable PSRO measurement circuit is used to measure the frequency dependent capacitance of a target through silicon via (TSV) or other conductive structure. Measurements of the target structure are aided by using adjustable resistors and a de-embedding structure to measure the effects of parasitic capacitance, C | 12-23-2010 |
20100327883 | INDUCTIVE DELTA C EVALUATION FOR PRESSURE SENSORS - A measuring device has a sensor unit and an evaluation unit which is electrically isolated from the sensor unit by a partition wall. The sensor unit includes a first capacitive sensor which is electrically connected to a first coil to form a first oscillating circuit, and a reference capacitor which is electrically connected to a second coil to form a second oscillating circuit. The evaluation unit includes a third coil which is inductively coupled to the first coil and the second coil, and the evaluation unit is designed to determine and output a beat frequency of a beat signal which is inductively injected into the third coil by the first oscillating circuit and the second oscillating circuit. | 12-30-2010 |
20110031985 | MECHANISMS FOR DETECTING TAMPERING OF AN ELECTRONIC DEVICE - An electronic device has a chassis, and a printed wiring board (PWB) having a hole. A fastener is installed in the hole thereby securing the PWB to the chassis. A pair of conductive traces is formed in the PWB. A cap, being an amount of conductive glue, covers a part of the fastener and fills an electrically insulating gap between the two traces, to thereby form a conductive path that connects the two traces. A sensing circuit is coupled to the traces, to detect a change in impedance of the path and signal a tamper event alert. Other embodiments are also described and claimed. | 02-10-2011 |
20110043227 | METHODS AND APPARATUS FOR CAPACITIVE SENSING - The present disclosure addresses methods and apparatus facilitating capacitive sensing using a conductive surface, and facilitating the sensing of proximity to the conductive surface. The sensed proximity will often be that of a user, but can be another source of a reference voltage potential. In some examples, the described systems are capable of sensing capacitance (including parasitic capacitance) in a circuit that includes the outer conductive surface, and where that outer conductive surface is at a floating electrical potential. In some systems, the systems can be switched between two operating modes, a first mode in which the system will sense proximity to the conductive surface, and a second mode in which the system will use a capacitance measurement to sense contact with the conductive surface. | 02-24-2011 |
20110050256 | SENSOR SYSTEM FOR MONITORING SURROUNDINGS ON A MECHANICAL COMPONENT AND A METHOD FOR ACTIVATING AND EVALUATING THE SENSOR SYSTEM - A sensor system and an evaluation method for monitoring surroundings on a mechanical component, having at least one capacitive sensor element that is attachable on the surface of machines or machine parts, in which at least one sensor element is made up of a layered structure of flexible, electrically conductive and electrically insulating layers, electrically conductive surfaces of one layer being positioned with lateral spacing above insulating layers lying between them in such a way that electrical field lines form between the conductive surfaces, which change measurably upon approach to and/or contact with a body or object. | 03-03-2011 |
20110068811 | CAPACITANCE METER, METHOD, COMPUTER PROGRAM AND COMPUTER PROGRAM PRODUCT FOR IMPROVED CAPACITANCE MEASUREMENT - A capacitance meter including an AC source providing a measurement voltage with a measurement frequency to a capacitor. A current sensor is arranged to measure a current going to or from the capacitance meter. A voltage sensor is arranged to measure a voltage over the capacitor. A capacitance calculation unit is arranged to calculate, using a controller, a capacitance of the capacitor using a measured current from the current sensor, a measured voltage from the voltage sensor and the measurement frequency. The capacitance meter is arranged to obtain measurements using the current sensor and the voltage sensor during a measurement duration. The measurement frequency and the measurement duration are selected such that the measurement duration equals a multiple of the period of the measurement frequency, and the measurement duration equals a multiple of the period of a mains electricity. | 03-24-2011 |
20110101999 | METHOD, CAPACITANCE METER, COMPUTER PROGRAM AND COMPUTER PROGRAM PRODUCT FOR IMPROVED CAPACITANCE MEASUREMENT - A method for measuring a capacitance using a capacitance meter. The capacitance meter includes an AC power source with a controllable frequency which is fed to a capacitor to measure its capacitance. A first measurement of the capacitance is performed by the capacitance meter using a first frequency. When the first measurement of the capacitance indicates the capacitance is below a threshold capacitance a lower capacitance measurement is performed in the capacitance meter, using a second measurement of the capacitance using a second frequency. When the first measurement of the capacitance indicates the capacitance is above a threshold capacitance, a higher capacitance measurement is performed in the capacitance meter, using a second measurement of the capacitance using a third frequency, the third frequency being lower than the second frequency. | 05-05-2011 |
20110181305 | POSITION DETECTING DEVICE AND METHOD - A position detecting device includes: a transmitting conductor group formed of a plurality of conductors arranged in a first direction; a receiving conductor group formed of a plurality of conductors arranged in a second direction intersecting the first direction; a signal detecting circuit configured to detect a signal occurring in at least one of the transmitting conductor group and the receiving conductor group on a basis of position indication by an indicating object; a transmitting conductor selecting circuit; and a receiving conductor selecting circuit. Each of the transmitting conductor group and the receiving conductor group is sectioned into at least a first conductor group and a second conductor group adjacent to each other. Conductors are selected such that a direction of selecting each of the conductors forming the first conductor group and a direction of selecting each of the conductors forming the second conductor group are different from each other. | 07-28-2011 |
20110193572 | Determining a Dielectric Property of a Capacitor - An apparatus for determining at least one dielectric property of a capacitor arrangement, and especially for capacitive examination of a moving elongated test subject such as yarn. It contains an alternating signal generator for applying an electric alternating signal to the capacitor arrangement. The capacitor arrangement is uncoupled from the alternating signal generator by means of an amplifier in such a way that it does not relevantly influence the basic frequency and the signal shape of the applied alternating signal. Detection means detect an electric measuring variable of an electric signal tapped from the capacitor arrangement. The alternating signal generator is set up in such a way that at least one of the basic frequency and the signal shape of the applied alternating signal can be changed. | 08-11-2011 |
20130057302 | CAPACITIVE MEASURING CIRCUIT INSENSITIVE TO HIGH-FREQUENCY INTERFERENCE - The invention relates to a measuring circuit for measuring the capacitance of a measuring capacitor which has a first and a second measuring electrode and which is coupled to a charging capacitor, wherein the frequency of the output signal of the measuring circuit is a measure of the capacitance of the capacitor, and the measuring circuit comprises a buffer amplifier with which the point between the charging resistor and the measuring capacitor is connected to the other components of the measuring circuit. The buffer amplifier changes the high impedance level of the combination of the measuring capacitor and the charging resistor to a level at which low-pass filters can usefully be applied. Buffer amplifiers are also available with an input capacitance and input resistance such that the buffer amplifier already functions in itself as a low-pass filter. An external filter is then not necessary because the filter is already present in the buffer amplifier. | 03-07-2013 |
20130093439 | Capacitive Differential Quadrature Rotary Position Sensor - A rotary position sensor is provided that includes a sensing disc having an N-fold rotation symmetry and capacitive sensing pads arranged in an array pattern, where the array pattern has at least 4N-fold rotation symmetry, where N≧2, a scale disc disposed opposite the sensing disc, where the scale disc includes a pattern of conductive pads that have a sinusoidal-shape, where the pattern of sinusoidal-shaped conductive pads produce four sinusoidal capacitance waveforms in quadrature phase with the capacitive sensing pads as the sensing disc and the scale disc are rotated relative to one another to provide angular position information. to provide angular position information. This is achieved by making the overlapping area of the of the capacitive sensing pads change in a sinusoidal fashion with rotation. | 04-18-2013 |
20130141121 | "Robust Capacitive Measurement System", - A capacitive sensing circuit is disclosed, wherein the mixer is directly connected to the sense electrode. The AC transimpedance amplifier in front of the mixer in prior art is removed and replaced by a differential DC transimpedance amplifier respectively integrator. The mixer DC offset voltage or current together with the large amplification factor required after the mixer now would result in an inacceptable DC offset at the output of the signal chain. In order to eliminate the effect of the mixer offset, the amplifying stages after the mixer are AC coupled to the mixer output and one of the signals entering the mixer is phase modulated or amplitude modu | 06-06-2013 |
20130221993 | FREQUENCY HOPPING ALGORITHM FOR CAPACITANCE SENSING DEVICES - Apparatuses and methods of frequency hopping algorithms are described. One method listens to a noise level on multiple electrodes of a sense network at multiple operating frequencies. The method then selects one of the frequencies with a lowest noise level for scanning the electrodes to detect a conductive object proximate to the electrodes. | 08-29-2013 |
20130328576 | MEASUREMENT OF TRANSISTOR GATE SOURCE CAPACITANCE ON A DISPLAY SYSTEM SUBSTRATE USING A REPLICA TRANSISTOR - Better performance can be provided for a display system that has semiconductor microelectronic components such as demultiplexors, gate line and data line drivers, and pixel switches formed on the display substrate, e.g., a glass substrate that constitutes part of an active matrix display panel. A gate source capacitance of a constituent transistor of one of these microelectronic components, e.g., a pixel thin film transistor (TFT) that is part of a particular display element, may be measured using a replica component that emulates the behavior of the component. | 12-12-2013 |
20140002116 | CAPACITIVE SENSOR FOR AN ANTI-COLLISION APPARATUS | 01-02-2014 |
20140009176 | CAPACITANCE MEASUREMENT CIRCUIT - A resistor having a known resistance is coupled in series with a device under test (DUT) having an unknown capacitance. An ac signal source having a known fundamental frequency is coupled to drive the resistor to thereby produce a first ac signal. A phase controllable signal generator produces a second ac signal. The first and second ac signals are fed to a mixer. An output of the mixer is low pass filtered. A peak detector monitors the low pass filtered output while sweeping the phase controllable signal generator, until a peak is detected. The set phase corresponding to the detected peak is then used to obtain an estimate of the unknown DUT capacitance. Other embodiments are also described and claimed. | 01-09-2014 |
20140009177 | Device and Method for Determining Capacitance as a Function of Voltage - A device and method of determining a capacitance of a device is provided, which in one embodiment includes connecting a first terminal of a capacitor having a known capacitance to the first terminal of the device, applying an AC voltage to the first terminal of the device and the first terminal of the capacitor, measuring a current through the capacitor, measuring a current through the device, determining a first voltage across the device as a function of time, computing a capacitance of the device as a function of time by multiplying the capacitance of the capacitor by the ratio of the current through the device to the current through the capacitor, determining a capacitance of the device as a function of voltage based on the capacitance as a function of time and the first voltage across the device as a function of time, and outputting data of the first capacitance of the device as a function of voltage. | 01-09-2014 |
20140049274 | SYSTEM FOR MEASURING MATERIAL LEVELS USING CAPACITANCE AND TIME DOMAIN REFLECTOMETRY SENSORS - An apparatus and system for measuring levels of two or more materials maintained within a storage tank using a combination of both a capacitance sensor and a time domain reflectometry (“TDR”) waveguide sensor is disclosed. The apparatus includes a combined circuit for the capacitance sensor and TDR sensor that creates a separation between the return signal from the capacitance sensor and the TDR sensor. The need for the return signal separation is due to the generation of false reflection signals from the capacitance circuitry. In a preferred embodiment, the separation in time is created by moving the capacitance false reflections further in time than the true signal returns. An alternative preferred embodiment would delay the true TDR signals passed the capacitance false reflections. Another alternative preferred embodiment would provide a substantially matched impedance of the capacitance circuit to the TDR circuit, to substantially eliminate the false reflections. | 02-20-2014 |
20140191770 | CAPACITIVE SENSING DEVICE - A capacitive sensing device including logic components and a capacitive sensor having at least one electrode, said logic components and capacitive sensor being arranged to form an oscillator, where the capacitive sensor includes a plurality of capacitive sensing electrodes, as well as a selector arranged to form an oscillator selectively from a plurality of possible oscillators, by connecting the logic components with respectively, in the case of each oscillator formed, a given combination from the plurality of electrodes of the capacitive sensor including at least an emission electrode and a reception electrode forming a capacitor formed by means of mutual electrostatic coupling. | 07-10-2014 |
20140312922 | DEVICE AND METHOD FOR DETERMINING CAPACITANCE - A device and method of determining a capacitance of a device is provided, which in one embodiment includes connecting a first terminal of a capacitor having a known capacitance to the first terminal of the device, applying an AC voltage to the first terminal of the device and the first terminal of the capacitor, measuring a current through the capacitor, measuring a current through the device, determining a first voltage across the device as a function of time, computing a capacitance of the device as a function of time by multiplying the capacitance of the capacitor by the ratio of the current through the device to the current through the capacitor, determining a capacitance of the device as a function of voltage based on the capacitance as a function of time and the first voltage across the device as a function of time, and outputting data of the first capacitance of the device as a function of voltage. | 10-23-2014 |
20150042365 | DETECTION CIRCUIT - A detection circuit is provided. A detection signal corresponding to an equivalent capacitance value of a micro-electro-mechanical system is generated by an oscillator, and the equivalent capacitance value of the micro-electro-mechanical system varies with a location of the micro-electro-mechanical system. | 02-12-2015 |
20150145536 | Methods and Systems for Production Testing of Capacitors - Systems and methods provide for testing a capacitor. The method includes: selecting a capacitor to be tested; generating an frequency signal from a source voltage which passes through a resistor, while connecting and disconnecting the capacitor, which results in an output signal; and measuring a relative level of a sideband associated with the output signal to estimate a size of the selected capacitor. | 05-28-2015 |
20150316372 | SYSTEM FOR OUTPUTTING DEGREE OF INCLINATION OF ELECTRONIC DEVICE - A system includes a frequency signal generator, a capacitor sensor, a frequency-voltage converter, and a degree of inclination displaying device. The capacitor sensor can be attached to an electronic device and includes a variable capacitor having a capacitance which varies in dependence upon a degree of inclination of the electronic device. The frequency signal generator outputs a frequency signal to the frequency-voltage converter. The capacitor sensor outputs a capacitor signal to the frequency-voltage converter. The frequency-voltage converter outputs a voltage signal to the degree of inclination displaying device according to the frequency signal and the capacitor signal. The degree of inclination displaying device obtains the degree of inclination of the electronic device according to the voltage signal and displays the degree of inclination. | 11-05-2015 |
20160025786 | METHOD AND APPARATUS FOR SENSING CAPACITANCE VALUE AND CONVERTING IT INTO DIGITAL FORMAT - A capacitive sensing system are configured to sense a capacitance value and convert the sensed capacitance value to a digital format. The capacitive sensing system provides good selectivity and immunity to noise and interference, which can be further enhanced by enabling spread spectrum excitation. In some embodiments, the capacitive sensing system utilizes a sinusoidal excitation signal that results in low electromagnetic emissions, limited to narrow frequency band. In some embodiments, the capacitive sensing system is configured to operate in a spread spectrum mode, in which the majority of the excitation signal power is carried in the assigned bandwidth. The excitation frequency and the bandwidth of the spread spectrum excitation signal are programmable in a wide range, which allows for avoiding frequency conflicts in the operating environment. | 01-28-2016 |
20160161436 | Electrical Capacitance Volume Tomography Sensor for Inspection of Post-Tensioned Tendons - The present invention provides a system and apparatus for inspecting tendons and cable stays in bridges and structures using multi-frequency excitation of an ECVT sensor. | 06-09-2016 |
324682000 | Including a tuned or resonant circuit | 15 |
20080204050 | Method of Measuring Electronic Device and Measuring Apparatus - In a method for measuring an electronic device which is an object to be measured, a passive element is connected to the electronic device in parallel, and electric parameters of the electronic device are extracted by measuring an impedance of the entire circuit. | 08-28-2008 |
20080204051 | CAPACITIVE SENSOR - A capacitive sensor with at least one reference impedance and at least one measuring condenser ( | 08-28-2008 |
20080278179 | Method and measurement apparatus for determining the transition impedance between two parts of a subdivided neutral electrode - A method and a measurement apparatus are provided for determining the transition impedance between two electrode parts of a subdivided neutral electrode used in high-frequency surgery. These makes it possible for the purely capacitive component of the transition impedance to be measured. For this purpose a resonant-frequency shift is measured, which occurs when a basic resonant circuit is expanded to an expanded resonant circuit by incorporating the two electrode parts into it in parallel. In particular, in order to determine the basic resonant frequency of the basic resonant circuit and/or the sample resonant frequency of the expanded resonant circuit, the phase shift between current and voltage is measured and the frequency is adjusted until current and voltage are in phase. | 11-13-2008 |
20090189619 | SYSTEMS AND METHODS FOR DETECTING CAPACITOR PROCESS VARIATION - A method for detecting capacitor variation in a device comprises operating an oscillator in the device, the oscillator being an Inductive-Capacitive (LC) oscillator and including an inductor of known value and a capacitor under test, comparing an output of the oscillator to a reference output, and evaluating variation for a plurality of capacitors in the device based on the comparing. | 07-30-2009 |
20090219039 | METHOD AND CIRCUIT FOR DETECTING THE PRESENCE, POSITION AND/OR APPROACH OF AN OBJECT IN RELATIVE TO AT LEAST ONE ELECTRODE - A circuit for detecting the presence, position or the approach of an object in an observation area, the circuit has a sensor electrode assembly with an electrode that forms part of a capacitor system whose capacitance relative to a reference potential (e.g. ground) is dependent on the presence, position or approach of objects in the observation area. An evaluation circuit coupled to the sensor electrode detects a phase shift of the capacitance of the condenser system. An LC network is coupled to the capacitor system, and an oscillator connected to the electrode applies a frequency to the system formed by including the electrode and the LC network at a frequency within the range of a parallel resonance frequency of the LC network. | 09-03-2009 |
20090267621 | Method and device for rapid non-destructive quality control of powdered materials - Method and related device intended for rapid non-destructive testing of powdered materials with low electric conductivity such as cement and cement-based compositions through determination of their electrical properties. The invention involves an electromagnetic method, including an electronic circuit for generating an electric field in a capacitance probe that is inserted into the powder to be tested. Electrical properties of powdered materials are determined on the basis of a set of the values for a set of parameters including quality factor (Q-factor), capacitance, dissipation factor, and dielectric permeability of the material. These parameter values can be related to such characteristics as moisture content, particle size, and material composition. The method and device can indicate the differences between the samples with various quantities of unwanted components or reaction products, and the extent of sample ageing. | 10-29-2009 |
20100327884 | Liquid level and quality sensing apparatus, systems and methods using EMF wave propagation - A liquid level, composition and contamination sensor generates an RF signal across a resonant circuit that includes a variable inductor and capacitor. The resulting electromagnetic radiation is propagated into the liquid and changes in impedance and resonance of the resonant circuit that result from changes in the conductivity and dielectric properties of the liquid, which are proportional to liquid content and volume, are detected. The conductivity and dielectric properties of the liquid are measured, based on the changed impedance and resonance of the resonant circuit, and are compared to determine aging and contamination of the urea solution by other liquids. Also, an optical sensor may be submerged in the liquid to determine the refractive index of the liquid. The refractive index of the liquid may be used to determine: if the liquid is water or a urea solution; the concentration of a urea solution. | 12-30-2010 |
20110133759 | Quick connect sensor apparatus - An electronic sensor for determining if a metal hose connector is fully snapped into its mating plastic connector. This sensor detects the metal hose in position by having a coil in position over the plastic connector and at the end of the metal hose when it is in correct position. The metal of the hose interacts with the magnetic field of the coil to both increase the inductance and greatly reduce the ‘Q’ because of the “shorted turn” effect of the round metal hose. The sensor inherently detects faults in its own circuit because of the comparator voltage window. Faults such as an open coil, oscillator or rectifier failure will appear at the output as “hose disconnected” which is the desirable failure mode. The invention also detects external faults because of the two non-zero, non-line voltages seen during normal operation. | 06-09-2011 |
20120001647 | TOUCH AND APPROACH DETECTION WITH CAPACITATIVE SENSORS - Provided by the invention is a sensor device for the detection of touch or approach of an object. A server circuit of the sensor device according to the invention is formed in such a manner, that the server circuit alone (i.e. without co-operation with a client circuit) may be used as approaching sensor, at the same time however also together with one or several client circuits may be implemented a sensor network, in which the client circuits preferably are fed with energy with the electric field of the server electrode. | 01-05-2012 |
20120235692 | METHOD AND DEVICE FOR RAPID NON-DESTRUCTIVE QUALITY CONTROL OF POWDERED MATERIALS - A method of non-destructive testing for quality control of powdered materials having dielectric properties based on the use of electromagnetic capacitance techniques. | 09-20-2012 |
20130063166 | LOW POWER HIGH RESOLUTION SENSOR INTERFACE - A sensor interface circuit is provided for resolving sensor signals from a plurality of sensors into a digital sensor signal, the sensor interface circuit comprising: a relaxation oscillator for receiving and pre-processing the sensor signals to generate an analog sensor signal, the relaxation oscillator comprising one or more dynamic circuits; and a monitoring module for receiving the analog sensor signal and generating the digital sensor signal in response thereto. There is also provided a sensor system front-end and a relaxation oscillator. | 03-14-2013 |
20130106445 | POWDER SENSOR | 05-02-2013 |
20130162272 | INCREMENTAL CAPACITIVE ANGULAR DISPLACEMENT TRANSDUCER - Incremental angular capacitive displacement transducer comprising movable ( | 06-27-2013 |
20150109004 | NON-INVASIVE MEASUREMENT OF DIELECTRIC PROPERTIES OF A SUBSTANCE - The invention pertains to an apparatus and a method for determining a dielectric property of a first substance in a composition in a non-invasive manner. The composition includes at least the first substance to be measured and a second substance. The method uses and apparatus includes a capacitor for creating a field into which the composition can be introduced at least in part, where the capacitor is part of an oscillator circuit, and the oscillator circuit is coupled to a device for determining the resonance frequency of the oscillator circuit. The capacitor includes a layer of a non-conducting material such that the composition, when introduced at least in part into the field of the capacitor, does not come into an electrical contact with the electrodes of the capacitor. | 04-23-2015 |
20150130482 | CAPACITIVE SENSING SYSTEM AND METHOD - The invention provides a capacitive sensor circuit in which a capacitance to be sensed is selectively coupled into a ring oscillator circuit. The ring oscillator frequency is measured with the capacitance coupled and not coupled, and a capacitance is derived from the change in ring oscillator frequency. | 05-14-2015 |