Electromagnetic Patents (Class 73/728)
  • Patent number: 10962433
    Abstract: The invention provides a pressure sensor (10) that can be produced at low cost, operates more accurately and resists to high burst pressures. The pressure sensor (10) comprises at least one membrane (12) and a magneto-elastic detection device (14) for magneto-elastically detecting mechanical stress caused by pressurization.
    Type: Grant
    Filed: March 5, 2018
    Date of Patent: March 30, 2021
    Assignee: TRAFAG AG
    Inventor: Christoph Schanz
  • Patent number: 10908033
    Abstract: A pneumatic-based tactile sensor according to an exemplary embodiment of the present invention includes: a tactile sense transmitting pneumatic unit for generating pneumatic pressure by an external load applied to a first side; and a tactile sense receiving sensor unit for measuring the load by transforming a magnitude of pneumatic pressure of the tactile sense transmitting pneumatic unit into a displacement.
    Type: Grant
    Filed: June 30, 2017
    Date of Patent: February 2, 2021
    Assignee: KOREA INSTITUTE OF MACHINERY & MATERIALS
    Inventors: Hyun eui Lim, Sunjong Oh, Young Do Jung
  • Patent number: 9952112
    Abstract: According to an embodiment, a pressure sensor includes a support part, a flexible membrane part, and a magnetoresistive element. The flexible membrane part is supported by the support part, and includes a first region and a second region with rigidity lower than rigidity of the first region. The magnetoresistive element is provided on the membrane part, and includes a first magnetic layer, a second magnetic layer, and a spacer layer provided between the first magnetic layer and the second magnetic layer.
    Type: Grant
    Filed: May 26, 2015
    Date of Patent: April 24, 2018
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kei Masunishi, Hideaki Fukuzawa, Yoshihiko Fuji, Akiko Yuzawa, Kazuaki Okamoto
  • Patent number: 9915573
    Abstract: Pressure sensing systems comprising bulk-solidifying amorphous alloys and pressure-sensitive switches containing bulk-solidifying amorphous alloys. The bulk-solidifying amorphous alloys are capable of repeated deformation upon application of pressure, and change their electrical resistivity upon deformation, thereby enabling measurement of the change in resistivity and consequently, measuring the deformation and amount of pressure applied.
    Type: Grant
    Filed: March 7, 2016
    Date of Patent: March 13, 2018
    Assignee: Apple Inc.
    Inventors: Christopher D. Prest, Matthew S. Scott, Stephen P. Zadesky, Dermot J. Stratton, Joseph C. Poole, Theodore A. Waniuk
  • Patent number: 9759618
    Abstract: According to one embodiment, a pressure sensor includes a base, and a first sensor unit. The first sensor unit includes a first transducer thin film, a first strain sensing device and a second strain sensing device. The first strain sensing device includes a first magnetic layer, a second magnetic layer, and a first intermediate layer provided between the first and the second magnetic layers. The second strain sensing device is provided apart from the first strain sensing device on the first membrane surface and provided at a location different from a location of the barycenter, the second strain sensing device including a third magnetic layer, a fourth magnetic layer, and a second intermediate layer provided between the third and the fourth magnetic layers, the first and the second intermediate layers being nonmagnetic. The first and the second strain sensing devices, and the barycenter are in a straight line.
    Type: Grant
    Filed: October 29, 2014
    Date of Patent: September 12, 2017
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Akihiko Enamito, Osamu Nishimura, Michiko Hara, Hiromi Yuasa, Yoshihiko Fuji, Masayuki Kii, Eizo Fujisawa
  • Patent number: 9654883
    Abstract: According to one embodiment, a strain sensing element provided on a deformable substrate includes: a first magnetic layer; a second magnetic layer; a spacer layer; and a bias layer. Magnetization of the second magnetic layer changes according to deformation of the substrate. The spacer layer is provided between the first magnetic layer and the second magnetic layer. The second magnetic layer is provided between the spacer layer and the bias layer. The bias layer is configured to apply a bias to the second magnetic layer.
    Type: Grant
    Filed: September 3, 2014
    Date of Patent: May 16, 2017
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshihiko Fuji, Hideaki Fukuzawa, Shiori Kaji
  • Patent number: 9607760
    Abstract: An apparatus for solidifying liquid in a magnetic field includes a magnetic circuit applying the magnetic field greater than or equal to about 1 tesla to a solidified part.
    Type: Grant
    Filed: December 9, 2013
    Date of Patent: March 28, 2017
    Assignee: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Tomokazu Fukuzaki, Kazutomo Abe
  • Patent number: 8857277
    Abstract: The present invention provides a pressure detecting circuit, which is electrically connected to a coil to receive an induced electromotive force from the coil, including a movement detecting unit electrically connected to the coil to receive the induced electromotive force from the coil and find a distance of the movement of the magnetic device according to the induced electromotive force; and a converting unit electrically connected to the movement detecting unit to generate the voltage signal to indicate the distance. In addition, the present invention further provides a pressure gauge incorporated with the pressure detecting circuit.
    Type: Grant
    Filed: September 13, 2011
    Date of Patent: October 14, 2014
    Assignee: Grand Mate Co., Ltd.
    Inventors: Chung-Chin Huang, Chin-Ying Huang, Hsin-Ming Huang, Hsing-Hsiung Huang, Kuan-Chou Lin, Yen-Jen Yen, Chiang-Wen Lai
  • Patent number: 8813572
    Abstract: A pressure transmitter for measuring a pressure of a process fluid comprises a transmitter housing, a pressure sensor, a hydraulic relay system, a ferrofluid and transmitter electronics. The capacitance-based pressure sensor senses the pressure of the process fluid and is disposed within the housing. The hydraulic relay system comprises an isolation diaphragm positioned on an exterior of the transmitter housing, and an isolation tube extending from the pressure sensor to the isolation diaphragm. The ferrofluid is located in the isolation tube to transmit a change in the pressure of the process fluid at the isolation diaphragm to the sensor. The transmitter electronics are positioned within the housing and are configured to receive and condition a pressure signal from the pressure sensor.
    Type: Grant
    Filed: December 6, 2011
    Date of Patent: August 26, 2014
    Assignee: Rosemount Inc.
    Inventor: Robert Carl Hedtke
  • Publication number: 20140224028
    Abstract: A pressure sensor system for acquiring a pressure of a fluid medium in a measurement chamber, and a method for the production thereof, are provided, having a sensor housing, at least one sensor element that is situated on a bearer such that it can be exposed to the medium in order to measure a pressure of the medium, and an evaluation circuit for outputting a signal that indicates the pressure acting on the sensor element. The evaluation circuit is situated outside the medium and is energetically connected to the sensor element in contactless fashion. The bearer is connected to the sensor housing such that the evaluation circuit is situated inside the sensor housing.
    Type: Application
    Filed: April 27, 2012
    Publication date: August 14, 2014
    Inventors: Alexander Lux, Martin Mast
  • Publication number: 20140150560
    Abstract: A pressure sensor assembly includes a pressure sensor die and a circuit die. The pressure sensor die includes a MEMS pressure sensor and an electromagnetic shield layer. The circuit die includes an ASIC configured to generate an electrical output corresponding to a pressure sensed by the MEMS pressure sensor. The ASIC is electrically connected to the pressure sensor die. The electromagnetic shield is configured to shield the MEMS pressure sensor and the ASIC from electromagnetic radiation.
    Type: Application
    Filed: November 27, 2013
    Publication date: June 5, 2014
    Applicant: Robert Bosch GmbH
    Inventors: Gary O'Brien, Ando Feyh, Andrew Graham
  • Patent number: 8707793
    Abstract: A sensor system includes: an at least partially magnetoelastic deformation element for measuring pressures, caused by a fluid, that are able to be applied to the magnetoelastic deformation element; and a magnetic circuit formed via a magnetic flux feedback and having a sensor unit and an evaluation unit. The sensor unit is positioned at the deformation element and the evaluation unit having an evaluation coil is structurally separated from, yet inductively coupled to, the sensor unit. The sensor unit has a sensor coil positioned on the deformation element and the evaluation unit has the evaluation coil that is inductively coupled to the sensor coil, the sensor coil forms a resonant circuit, using its own parasitic capacitance or using an additional capacitance, which is able to be energized by the evaluation coil in free resonance with strong or weak inductive coupling by a magnetic circuit enclosing the two coils.
    Type: Grant
    Filed: November 24, 2009
    Date of Patent: April 29, 2014
    Assignee: Robert Bosch GmbH
    Inventors: Reinhard Nopper, Denis Gugel, Andreas Arlt, Klaus Walter, Frank Schatz, Janpeter Wolff
  • Patent number: 8631710
    Abstract: The invention relates to a measuring apparatus for measuring a measurement variable of a fluid, in particular a sensor, such as a pressure sensor or a travel sensor. The measuring apparatus has a housing, a diaphragm which is arranged in and/or on the housing and an elastic element, which is designed in the manner of a leaf spring, for restoring the diaphragm. A signal transmitter is operatively connected to the diaphragm and/or to the elastic element, and a signal receiver interacts with the signal transmitter. Structures for providing reinforcement are arranged in the edge region and/or in the center of the elastic element.
    Type: Grant
    Filed: December 1, 2011
    Date of Patent: January 21, 2014
    Assignee: Marquardt Mechatronik GmbH
    Inventors: Dietmar Weisser, Benjamin Schullcke, Heinrich Müller, Markus Scheiter
  • Patent number: 8590386
    Abstract: A pressure detection device includes a buffer member and a sensor assembly. The buffer member is deformable by a pressure change, and includes a plurality of magnets in an evenly dispersed arrangement. The sensor assembly includes at least one magnetic sensor to detect a variation of a magnetic field accompanied by deformation of the buffer member.
    Type: Grant
    Filed: April 7, 2011
    Date of Patent: November 26, 2013
    Assignee: Seiko Epson Corporation
    Inventors: Kesatoshi Takeuchi, Yojiro Okakura
  • Patent number: 8516893
    Abstract: A modified inductive pressure sensor for detecting operating parameters of an electric household appliance such as a washing or drying machine, provided with a relatively movable component with respect to the carcass (tank or basket), of the type including a rigid casing accommodating a deformable membrane sensitive to hydraulic pressure, a core made of ferromagnetic material and operatively associated to the membrane, and a winding fixed to the casing and operatively coupled to the core to form a variable inductance inductor; wherein a mass is accommodated within the casing and in immediate proximity of said membrane, free to move with respect to the casing in at least one direction corresponding to the axis of the winding.
    Type: Grant
    Filed: December 4, 2009
    Date of Patent: August 27, 2013
    Assignee: Illinois Tool Works Inc.
    Inventors: Sergio Giordano, Igor Kranjc
  • Publication number: 20130139565
    Abstract: A pressure transmitter for measuring a pressure of a process fluid comprises a transmitter housing, a pressure sensor, a hydraulic relay system, a ferrofluid and transmitter electronics. The capacitance-based pressure sensor senses the pressure of the process fluid and is disposed within the housing. The hydraulic relay system comprises an isolation diaphragm positioned on an exterior of the transmitter housing, and an isolation tube extending from the pressure sensor to the isolation diaphragm. The ferrofluid is located in the isolation tube to transmit a change in the pressure of the process fluid at the isolation diaphragm to the sensor. The transmitter electronics are positioned within the housing and are configured to receive and condition a pressure signal from the pressure sensor.
    Type: Application
    Filed: December 6, 2011
    Publication date: June 6, 2013
    Applicant: ROSEMOUNT INC.
    Inventor: Robert Carl Hedtke
  • Publication number: 20130073225
    Abstract: The present invention provides a pressure gauge for measuring a pressure of a source. The pressure gauge includes a case, a flexible film, a magnetic device, a coil, a processor, and a screen. The case has a bore connecting the source. The coil is provided in the case. The flexible film is provided on an inner side of the case to cover the bore that the flexible film is expandable by the pressure of the source. The magnetic device is received in the case to be moved relative to the coil by the flexible film. The movement of the magnetic device causes the coil to generate an induced electromotive force, and the processor may find the gas pressure according to the induced electromotive force, and show it on the screen.
    Type: Application
    Filed: September 15, 2011
    Publication date: March 21, 2013
    Applicant: GRAND MATE CO., LTD.
    Inventors: Chung-Chin Huang, Chin-Ying Huang, Hsin-Ming Huang, Hsing-Hsiung Huang, Kuan-Chou Lin, Yen-Jen Yen, Chiang-Wen Lai
  • Publication number: 20130071797
    Abstract: The present invention provides a water heater, including a combustor, a gas pipe, a combustion controller, a pressure gauge, and a controller. The gas pipe supplies the combustor gas. The combustion controller controls combustion of the combustor. The pressure gauge detects a gas pressure in the gas pipe and generates an electrical signal in association with the gas pressure. The controller is electrically connected to the gas gauge and the combustion controller to receive the electrical signal from the gas gauge and controls the combustion controller according to the electrical signal to adjust the combustion of the combustor. In addition, the present invention further provides a method of controlling the water heater.
    Type: Application
    Filed: September 16, 2011
    Publication date: March 21, 2013
    Applicant: GRAND MATE CO., LTD.
    Inventors: CHUNG-CHIN HUANG, Chin-Ying Huang, Hsin-Ming Huang, Hsing-Hsiung Huang, Kuan-Chou Lin, Yen-Jen Yen
  • Patent number: 8327713
    Abstract: A pressure sensor includes a sensor body which is arranged to couple to a process pressure. The sensor body has a magnetic property which changes as a function of pressure applied by a process fluid. A sensor is coupled to the sensor body and is configured to measure pressure of fluid in the sensor body as a function of a change of magnetic property of the sensor body.
    Type: Grant
    Filed: December 3, 2008
    Date of Patent: December 11, 2012
    Assignee: Rosemount Inc.
    Inventor: Charles R. Willcox
  • Publication number: 20120125116
    Abstract: The invention relates to a measuring apparatus for measuring a measurement variable of a fluid, in particular a sensor, such as a pressure sensor or a travel sensor. The measuring apparatus has a housing, a diaphragm which is arranged in and/or on the housing and an elastic element, which is designed in the manner of a leaf spring, for restoring the diaphragm. A signal transmitter is operatively connected to the diaphragm and/or to the elastic element, and a signal receiver interacts with the signal transmitter. Structures for providing reinforcement are arranged in the edge region and/or in the center of the elastic element.
    Type: Application
    Filed: December 1, 2011
    Publication date: May 24, 2012
    Applicant: Marquardt Mechatronik GmbH
    Inventors: Dietmar WEISSER, Benjamin SCHULLCKE, Heinrich MÜLLER, Markus SCHEITER
  • Patent number: 8156817
    Abstract: Provided is a pressure detection device capable of easy installation and removal of a sensor in/from a diaphragm, measurement of a pressure in a wide rage, and manufacture at a low cost while reducing a size. A sensor part (A) has: a magnet (12) being applied with a load produced by pressing of a diaphragm (8); and a magnet cap (11) covering the magnet (12). The diaphragm (8) has an intra-diaphragm magnetic body (9) buried therein. The intra-diaphragm magnetic body (9) has a protrusion part protruding from the diaphragm (8) so as to be in contact with the magnet (12). The magnet cap (11) has an opening part enabling the protrusion part of the intra-diaphragm magnetic body (9) and the magnet (12) to be joined together.
    Type: Grant
    Filed: March 29, 2006
    Date of Patent: April 17, 2012
    Assignee: JMS Co., Ltd
    Inventors: Mitsuru Kaneko, Aki Kitani
  • Publication number: 20110320142
    Abstract: A temperature independent pressure sensor for selectively determining pressure is provided. The sensor comprises a resonance sensor circuit, a pressure sensitive component disposed on the sensor circuit, and an electromagnetic field modulator. A temperature independent pressure sensor system comprises a resonance sensor circuit, a pressure sensitive component disposed on the sensor circuit, an electromagnetic field modulator, and a processor that generates a multivariate analysis of sensor response pattern that is based on a change in an environmental pressure of the sensor system. A method of detecting a pressure response pattern in a temperature independent manner is also provided.
    Type: Application
    Filed: June 28, 2010
    Publication date: December 29, 2011
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Cheryl Margaret Surman, Radislav Alexandrovich Potyrailo, William Guy Morris
  • Publication number: 20110232390
    Abstract: An elastic material for pressure measurement, containing an elastic resin composition having at least either a urethane bond or a urea bond and being obtained by reacting an isocyanate with (A) a linear polyol and then curing the obtained prepolymer with use of a curing agent having two —NH2 groups in one molecule.
    Type: Application
    Filed: March 29, 2011
    Publication date: September 29, 2011
    Applicant: FUJIFILM Corporation
    Inventors: Yoshikazu MATSUMOTO, Mitsuru SAWANO
  • Patent number: 7992444
    Abstract: The pressure detection device includes a buffer member deformable by a pressure change, including one or more magnets, and a sensor assembly including one or more magnetic sensors to detect a variation of a magnetic field accompanied by deformation of the buffer member.
    Type: Grant
    Filed: February 26, 2009
    Date of Patent: August 9, 2011
    Assignee: Seiko Epson Corporation
    Inventors: Kesatoshi Takeuchi, Yojiro Okakura
  • Publication number: 20100099008
    Abstract: A pressure sensor adapted to provide a high resolution at a low pressure and a high pressure of an operating range is provided. The pressure sensor includes a body having an interface sur ace, a membrane sealingly disposed in the cavity adjacent the interface surface, and a sensing element in communication with the membrane. A fuel cell system including the pressure sensor is also provided.
    Type: Application
    Filed: October 21, 2008
    Publication date: April 22, 2010
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventor: Harald Schlag
  • Patent number: 7677108
    Abstract: The invention relates to a pressure sensor capable of measuring pressure accurately, and more particularly, to a pressure sensor comprising a box-shaped magnet, optionally having an inclined upper surface with a right side portion protruding higher than a left side portion, wherein the magnet is configured to radiate linear magnetic flux density in response to a change in distance along a straight line spaced uniformly apart from an N or S pole surface, whereby the pressure sensor can accurately detect a displacement in distance (position) and thus a pressure difference based on the displacement. The pressure sensor further includes a pipe connecting negative and positive pressures, a diaphragm movable in response to a difference between negative and positive pressures, a diaphragm support attached to a side of the diaphragm, a magnet attached to the diaphragm support to radiate linear magnetic flux density, a spring supporting the magnet, and the diaphragm and upper and lower cases housing these components.
    Type: Grant
    Filed: January 9, 2007
    Date of Patent: March 16, 2010
    Assignee: Kyungdong Network Co., Ltd.
    Inventor: Si-Hwan Kim
  • Publication number: 20090007683
    Abstract: Provided is a pressure detection device capable of easy installation and removal of a sensor in/from a diaphragm, measurement of a pressure in a wide rage, and manufacture at a low cost while reducing a size. A sensor part (A) has: a magnet (12) being applied with a load produced by pressing of a diaphragm (8); and a magnet cap (11) covering the magnet (12). The diaphragm (8) has an intra-diaphragm magnetic body (9) buried therein. The intra-diaphragm magnetic body (9) has a protrusion part protruding from the diaphragm (8) so as to be in contact with the magnet (12). The magnet cap (11) has an opening part enabling the protrusion part of the intra-diaphragm magnetic body (9) and the magnet (12) to be joined together.
    Type: Application
    Filed: March 29, 2006
    Publication date: January 8, 2009
    Applicant: JMS CO., LTD
    Inventors: Mitsuru Kaneko, Aki Kitani
  • Patent number: 7444878
    Abstract: A pressure sensor (S) includes an antenna member (10) that is adapted to be resonantly responsive to a desired frequency of electromagnetic radiation (12). An inductance changing body formed from a compressible dielectric material (14) is positioned in proximity to the antenna member (10). A housing member (16) houses the antenna member (10) in a desired proximity to the compressible dielectric material (14). The compression of the dielectric material (14) changes the effective dielectric constant of the antenna (10).
    Type: Grant
    Filed: October 30, 2006
    Date of Patent: November 4, 2008
    Assignee: Northrop Grumman Systems Corporation
    Inventor: David R. Pepples
  • Patent number: 7395717
    Abstract: The invention relates to a flexible, resilient capacitive sensor suitable for large-scale manufacturing. The sensor comprises a dielectric, an electrically conductive layer on the first side of the dielectric layer, an electrically conductive layer on a second side of the dielectric layer, and a capacitance meter electrically connected to the two conductive layers to detect changes in capacitance upon application of a force to the detector. The conductive layers are configured to determine the position of the applied force. The sensor may be shielded to reduce the effects of outside interference.
    Type: Grant
    Filed: February 10, 2006
    Date of Patent: July 8, 2008
    Assignee: Milliken & Company
    Inventors: Alfred R. DeAngelis, D. Bruce Wilson, Brian A. Mazzeo
  • Patent number: 7343809
    Abstract: In a method for determining the absolute pressure in pipes through which there is a fluid flow, in particular injection lines in diesel-operated internal combustion engine, a first signal from a first pressure sensor is detected. This first signal is integrated. The integrated signal is multiplied by a factor. This multiplied factor is then added to an operating pressure. This method advantageously allows detection of the absolute pressure within the injection line that connects the rail of an internal combustion engine to the corresponding injector.
    Type: Grant
    Filed: September 27, 2005
    Date of Patent: March 18, 2008
    Assignee: Siemens Aktiengesellschaft
    Inventors: Julian Baumann, Dirk Göger, Thomas Schlegl
  • Patent number: 7261005
    Abstract: A magneto-elastic torque sensor and system include a substrate and a magneto-elastic sensing component formed from or on the substrate. The magneto-elastic sensing component and the substrate together form a magneto-elastic torque sensor, which when subject to a stress associated with a torque, shifts a characteristic frequency thereof linearly in response to the torque, thereby inducing a pathway by which magneto-elastic energy is coupled to excite vibrations in a basal plane of the magneto-elastic sensor, thereby generating torque-based information based on a resonant frequency thereof.
    Type: Grant
    Filed: August 11, 2005
    Date of Patent: August 28, 2007
    Assignee: Honeywell International Inc.
    Inventors: Scott L. Bunyer, Richard M. Andrews, Fred W. Hintz, James ZT Liu, Steven J. Magee
  • Patent number: 7219552
    Abstract: A pressure sensor 10 includes a casing 12 configured to be able to be filled with a fluid 16 such as a liquid or a gas, in which at least part of a surface contacting this fluid 16 is formed of a giant magnetostrictive member 18 made of a giant magnetostrictive element, and detecting means for detecting a change in magnetic permeability or an amount of remanent magnetization attributable to expansion and contraction of the giant magnetostrictive member 18 based on a pressure change of the fluid 16 filled in this casing 12. The pressure sensor 10 can detect pressure at high sensitivity and high accuracy in a short time while achieving miniaturization of a device at the same time.
    Type: Grant
    Filed: March 11, 2004
    Date of Patent: May 22, 2007
    Assignee: TDK Corporation
    Inventor: Teruo Mori
  • Patent number: 7180285
    Abstract: The transducer (1) comprises: a rigid casing (2–4) in which a membrane (5) is clamped which, together with a portion of the casing (2–4), defines at least one chamber (6, 7) of variable volume; at least one winding (14); an interaction element (13), able to interact magnetically with the winding (14) under the effect of a displacement of the membrane (5), in such a way that the inductance of the winding (14) is variable in dependence on the relative position of the interaction element with respect to the winding (14), and circuit devices (17) connected to the winding (14) and operable to supply electrical signals of which one parameter, frequency for example, is variable in dependence on the inductance of the winding (14); the said circuit devices (17) including a memory (22) operable to store data representative of corrective values which, when applied in operation to the effective instantaneous values of the said parameter, make it possible to obtain correct values of the parameter corresponding to a predet
    Type: Grant
    Filed: March 18, 2003
    Date of Patent: February 20, 2007
    Assignee: Elbi International S.p.A.
    Inventors: Sabrina Bindocci, Paolo Da Pont, Paolo Senor, Giorgio Carrer, Sergio Giordano, Angelo Muneretto
  • Patent number: 7074191
    Abstract: A method for the non-intrusive measurement of blood pressure in a circuit of a dialysis machine, using a device provided with a sleeve forming a portion of the blood circuit and having at least one part which moves according to the pressure difference between the inside and the outside of the sleeve, and with an emitter and a receiver of electromagnetic waves. The method comprising the emission of a beam of electromagnetic waves and the receiving of a beam of electromagnetic waves reflected from the moving part, in order to measure the displacement of the moving part in such a way as to establish a relationship between the position of the moving part and the pressure of the blood circulating in the sleeve.
    Type: Grant
    Filed: May 16, 2002
    Date of Patent: July 11, 2006
    Assignee: Gambro Lundia AB
    Inventors: Antonio Bosetto, Annalisa Delnevo
  • Patent number: 7059194
    Abstract: The invention involves a pressure fault device for indicating a threshold pressure or a threshold differential pressure. The present invention provides a cost effective way to determine where a pressure problem has occurred. The device includes a housing having at least one inlet aperture and an indicator aperture and having first and second bores in fluid communication respectively with one inlet aperture and the indicator aperture. The device further includes a magnetic piston which is biased in the first bore toward one inlet aperture and moveable a predetermined distance in another direction in the first bore in response to inlet threshold pressure. The device further includes a magnetic responder which is moveable toward the indicator aperture in the second bore in response to movement of the magnetic piston. The device further includes a latching plate in magnetic relationship to the magnetic responder when the piston moves the predetermined distance.
    Type: Grant
    Filed: March 15, 2000
    Date of Patent: June 13, 2006
    Assignee: Mid-West Instruments
    Inventors: Michael A. Lueck, Michael P. Johnson, Randall R. Perkins
  • Patent number: 6910382
    Abstract: Ferromagnetic semiconductor-based sensor devices, including sensors for detecting pressure changes and sensors for detecting magnetic fields, such as switching events in a magnetic recording medium. The pressure sensors of the present invention detect pressure changes using magnetoresistive measurement techniques, and in particular GPHE techniques. Magnetic field detection sensors such as magnetic switching detection sensors include ferromagnetic semiconductor-based materials that provide enhanced sensitivity relative to known materials and techniques. Such magnetic switching detection sensors according to the present invention are particularly useful as a read head sensor for HDD and other magnetic storage technologies.
    Type: Grant
    Filed: June 23, 2003
    Date of Patent: June 28, 2005
    Assignee: California Institute of Technology
    Inventors: Hongxing Tang, Michael L. Roukes
  • Patent number: 6889555
    Abstract: An alternate method of designing and manufacturing a semiconductor pressure sensor inherently allows for significantly improved sensitivity, thereby allowing miniaturization of the sensor. As a result, the design lends itself to arranging the pressure sensors using this method in a two dimensional array, and measuring pressure distributions with very high lateral resolution. Furthermore, the design eliminates some of the processing complexities associated with the designs taught in the prior art, specifically those related to processes for manufacturing the plates of the parallel plate capacitor, or the piezoresistive strain elements. The invention allows the manufacture a two dimensional array of pressure sensors with very fine lateral resolution, which provides a much improved means over the prior art of recording fingerprints and the like.
    Type: Grant
    Filed: February 9, 2000
    Date of Patent: May 10, 2005
    Assignee: Fidelica Microsystems, Inc.
    Inventor: Srinivasan K. Ganapathi
  • Patent number: 6854335
    Abstract: A tire pressure reporting and warning system employs low-cost passive magnetically coupled pressure senders within the tires. These senders employ permanent magnets that rotate in response to pressure and may conveniently be mounted on the valve stem. A sender comprises a high-permeability helical ribbon that translates in response to pressure and penetrates a magnetic circuit. The magnetic circuit rotates into alignment with the helical ribbon. A novel feature of this invention is the dual-purpose use of the magnet both as a means for producing rotation in response to pressure and simultaneously for producing the remotely sensed external magnetic field. The direction and strength of the external field depends both on the rotation of the magnet with respect to the tire and on the overall orbital motion as the tire rotates.
    Type: Grant
    Filed: January 26, 2004
    Date of Patent: February 15, 2005
    Assignee: MLHO, Inc.
    Inventor: Alan Alexander Burns
  • Patent number: 6782753
    Abstract: A device and procedure for checking the health of a pressure transducer in situ is provided. The procedure includes measuring a fixed change in pressure above ambient pressure and a fixed change in pressure below ambient pressure. This is done by first sealing an enclosed volume around the transducer with a valve. A piston inside the sealed volume is then driven forward, compressing the enclosed gas, thereby increasing the pressure. A fixed pressure below ambient pressure is obtained by opening the valve, driving the piston forward, sealing the valve, and then retracting the piston. The output of the pressure transducer is recorded for both the overpressuring and the underpressuring. By comparing this data with data taken during a preoperative calibration, the health of the transducer is determined from the linearity, the hysteresis, and the repeatability of its output. The further addition of a thermometer allows constant offset error in the transducer output to be determined.
    Type: Grant
    Filed: November 9, 2001
    Date of Patent: August 31, 2004
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Christopher D. Immer, Anthony Eckhoff, Pedro J. Medelius, Richard T. Deyoe, Stanley O. Starr
  • Publication number: 20040093951
    Abstract: A magnetoelastic pressure sensor has an axially sensitive canister responsive to pressure induced tension. The sensor may have axially or circumferentially sensitive sensing structure. The pressure of a sense medium may be indirectly coupled to the interior of the chamber through an isolating member or medium. A reference structure may be provided for comparison with the sensing structure.
    Type: Application
    Filed: November 20, 2002
    Publication date: May 20, 2004
    Inventors: Jeffrey L. Viola, William T. Moore
  • Patent number: 6694822
    Abstract: The present invention provides a pressure sensing device that includes at least one GMR sensor, and preferably an array of GMR sensors, with each GMR sensor having a conducting spacer layer interposed between two ferromagnetic layers. In an unbiased state, the magnetization vector of each of the ferromagnetic layers is preferably parallel to each other. Upon application of a current, however, the magnetization vector of each ferromagnetic layer is changed, preferably to an antiparallel position, in which state the sensor is used to then sense stress applied thereto. Upon application of stress, the magnetization vectors of both free magnetic layers will rotate, thus causing a corresponding and proportionally related change in the resistance of the sensor. This change in resistance can be sensed and used to calculate the stress applied thereto.
    Type: Grant
    Filed: February 10, 2000
    Date of Patent: February 24, 2004
    Assignee: Fidelica Microsystems, Inc.
    Inventors: Srinivasan K. Ganapathi, Shiva Prakash
  • Patent number: 6626045
    Abstract: A pressure measurement device comprising a housing enclosing an elastic pressure measurement element and a magnet attached to the measurement element. First and second Hall sensors operatively positioned near the magnet are connected to an electrical circuit which processes the sensor outputs to provide first and second output signals. The positions of the Hall sensors can preferably each be adjusted from outside the housing.
    Type: Grant
    Filed: April 13, 2001
    Date of Patent: September 30, 2003
    Assignee: WIKA Alexander Wiegand GmbH & Co.
    Inventors: Josef Krumpolz, Bernhard Friebe
  • Patent number: 6591688
    Abstract: A load applied to a load cell's load-bearing member (21) causes that member to move against the force applied by springs (28 and 30) and thereby bring a magnet (24) into closer proximity to the ferromagnetic core (12) of a coil (10). Acting across a small gap, the magnet partially saturates a magnetic circuit that encloses the coil. This force-caused magnet motion changes the coil inductance and the magnetic circuit's degree of saturation. By applying to the coil (10) a brief voltage pulse without thereby heating it significantly, and by observing the coil current's resultant steady-state value and the rate at which the coil current approaches that value, an inductance-to-load converter (FIG. 4) calculates the applied load and the coil's temperature and generates outputs that represent them.
    Type: Grant
    Filed: July 24, 2001
    Date of Patent: July 15, 2003
    Assignee: Starr-Johnson
    Inventor: Hubert A. Wright
  • Patent number: 6581470
    Abstract: The transducer (1) includes a support structure (2, 3) in which a metal body (8) is mounted, having a flat surface (8a) and on the opposite side a cavity (8b) for exposure to a pressure to be transduced. A thin wall (8c), resiliently deformable like a membrane under the effect of the pressure, is defined between the bottom of the cavity (8b) and the flat surface (8a). An inductor (10) a body of ferromagnetic material (11)is securely fixed to the metal body (8) and has a flat surface (11a) facing the flat surface (8a) of the metal body (8) and an annular recess (12) which defines a central core (13) with a winding (16) arranged therein and a surrounding sleeve (14). A spacer wing (9) of paramagnetic or diamagnetic material, and a calibrated thickness, is interposed between the metal body (8) and the ferromagnetic body (11).
    Type: Grant
    Filed: October 9, 2001
    Date of Patent: June 24, 2003
    Assignee: Bitron S.p.A.
    Inventor: Ugo Sortilli
  • Patent number: 6539806
    Abstract: Magnetic force from a momentarily excited coil (34) results in oscillatory flexure of a flexible diaphragm (30) loaded on one side by a liquid (10) whose level is to be measured. A permanent magnet (42) mounted on the diaphragm (30) so moves with diaphragm flexure as to vary the magnetic saturation of a saturable circuit in which the coil (34) generates flux. By determining the coil's inductance under quiescent-diaphragm conditions, a computer (56) can infer the ambient pressure that bears upon the liquid (10). By compensating for the static pressure thus inferred, it can then determine liquid level by observing diaphragm oscillations reflected in coil electromotive force generated by the magnet (42) as the diaphram (30) undergoes oscillatory flexure in response to the coil's momentary excitation.
    Type: Grant
    Filed: March 7, 2001
    Date of Patent: April 1, 2003
    Assignee: Starr-Johnson
    Inventor: Hubert A. Wright
  • Patent number: 6532822
    Abstract: A pressure responsive mechanically resonant sensor device is provided that comprises a torsion pendulum driven at resonance. The pressure sensor includes a rigid frame to which is affixed a torsion pendulum comprising a hollow tube and a resonant mass as well as optimal means for applying energy to drive the torsion pendulum at resonance. The interior of the hollow tube portion of the torsion pendulum communicates through a pressure port in the rigid frame with the fluid whose pressure is to be sensed. The input pressure affects the torsion constant of the hollow tube and therefor changes the resonant frequency of the torsion pendulum, which frequency is converted into an indication of the sensed pressure.
    Type: Grant
    Filed: September 26, 2000
    Date of Patent: March 18, 2003
    Inventor: Clark Davis Boyd
  • Patent number: 6496019
    Abstract: A temperature compensated pressure sensor network for providing an output sensing signal representative of an applied pressure includes a reference oscillator circuit for providing a reference signal having an associated reference frequency. The oscillator circuit includes a first inductor pair electrically coupled in series, wherein the reference frequency is a predetermined function of a first inductance associated with the first inductor pair. The sensor network further includes a sensor circuit for providing a sensing signal having an associated sensing frequency. The sensor circuit includes a second inductor pair and a sensing capacitor electrically coupled in series, wherein the sensing frequency is a predetermined function of a second inductance associated with the second inductor pair and the applied pressure. The sensor network also includes a processor for receiving the reference signal and the sensing signal, and producing the output sensing signal.
    Type: Grant
    Filed: August 18, 2000
    Date of Patent: December 17, 2002
    Assignee: Setra Systems, Inc.
    Inventor: Dennis K. Briefer
  • Patent number: 6484586
    Abstract: A differential pressure transducer has a measurement chamber which is divided by a membrane into first and second measurement spaces which can be exposed to first and second pressures whereby differential pressure causes deflection of the membrane from its neutral position. A deflection sensor measures the deflection of the membrane and produces a deflection signal. An electromagnet arrangement produces a magnetic force which compensates for the deflection force which is caused by the differential pressure. The coil current for producing the magnetic compensation force represents a measure of the differential pressure.
    Type: Grant
    Filed: February 14, 2000
    Date of Patent: November 26, 2002
    Assignee: Haenni Instruments AG
    Inventors: Bertrand Dutoit, Andreas Friedrich, Kurt Hug, Radivojc Popovic
  • Patent number: 6473711
    Abstract: A pressure transmitter with first and second absolute pressure sensors receives process pressures from corresponding first and second process inlets. A transmitter circuit coupled to the first and second absolute pressure sensors generates a differential pressure type output. A third absolute pressure sensor coupled to the transmitter circuit receives atmospheric pressure from a third inlet. The transmitter circuit generates a second type of transmitter output that can be a gage or absolute pressure type. Single crystal. sapphire pressure sensors are preferred to provide enough accuracy for measuring accurately over 200:1 pressure range.
    Type: Grant
    Filed: August 13, 1999
    Date of Patent: October 29, 2002
    Assignee: Rosemount Inc.
    Inventors: Fred C. Sittler, Stanley E. Rud, Jr., Carl R. Gansen
  • Patent number: 6393921
    Abstract: A pressure sensing apparatus for operative arrangement within an environment, having: a sensor comprising a hermetically-sealed receptacle, at least one side of which has an flexible membrane to which a magnetically hard element is attached. Enclosed within the receptacle is a magnetostrictive element that vibrates in response to a time-varying magnetic field. Also included is a receiver to measure a plurality of successive values for magneto-elastic emission intensity of the sensor taken over an operating range of successive interrogation frequencies to identify a resonant frequency value for the sensor.
    Type: Grant
    Filed: February 11, 2000
    Date of Patent: May 28, 2002
    Assignee: University of Kentucky Research Foundation
    Inventors: Craig A. Grimes, Plamen G. Stoyanov, Dimitris Kouzoudis