Piezoresistive Patents (Class 73/721)
  • Publication number: 20020194923
    Abstract: There is disclosed a differential pressure sensor with a first and a second measuring chamber. Each measuring chamber being limited by a rigid carrier plate and a diaphragm plate, which is formed in the region of the measuring chamber as a pressure-sensitive measuring diaphragm. To design the differential pressure sensor to be resistant to overloading, the carrier plate is arranged between a first and a second diaphragm plate and has congruent concave depressions on opposite sides in the plane of the plate. The depressions are connected to one another by a central duct, penetrating the carrier plate perpendicularly to the plane of the plates. In the region of the measuring chambers, the diaphragm plates are formed congruently in relation to the depressions as pressure-sensitive measuring diaphragms. The measuring chambers are coupled to one another by a ram guided axially movably in the duct.
    Type: Application
    Filed: June 14, 2002
    Publication date: December 26, 2002
    Inventors: Wolfgang Scholz, Albrecht Vogel, Peter Krippner
  • Patent number: 6484589
    Abstract: Piezoelectric transducer assemblies that are useful for the monitoring of the gas output from a gas driven pump, wherein the assembly is not an integral part of the input or output flow stream of the material being pumped, but is used to monitor the exhaust gas flow of the gas driven pump.
    Type: Grant
    Filed: May 30, 2001
    Date of Patent: November 26, 2002
    Assignee: Senx Technology
    Inventor: John L. Brock
  • 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
  • Publication number: 20020134164
    Abstract: A pressure sensor device is described that has a diaphragm acted upon by a working medium, on a first side, and a sensor chip, which is disposed on a second side of the diaphragm that is remote from the working medium. There is formed in the sensor chip a measuring bridge having four sensor elements, which form two pairs disposed parallel, and the pairs are disposed at right angles to one another. The sensor elements are disposed such that they are closely spaced apart from one another in the edge region of the sensor chip that faces toward the central point of the diaphragm.
    Type: Application
    Filed: March 26, 2002
    Publication date: September 26, 2002
    Inventors: Johannes Ante, Christian Geiger, Markus Gilch, Hans-Peter Landgraf, Andreas Ott
  • Patent number: 6453748
    Abstract: A piezoresistive pressure sensor that makes use of n-type boron nitride as the piezoresistive material. The boron nitride enables the sensor to provide suitable performance in hostile environments. The sensor includes a titanium substrate covered with a diamond insulator layer. An n-type boron nitride piezoresistive element is deposited on the diamond layer, and is electrically connected to electrical contacts. The electrical contacts are electrically connected to a resistive measurement system for determining the resistance of the piezoresistive element. In an alternate embodiment, the boron nitride piezoresistive material is used in a micobolometer for a focal plane array.
    Type: Grant
    Filed: December 15, 1999
    Date of Patent: September 24, 2002
    Assignee: Wayne State University
    Inventor: Roger W. Pryor
  • Patent number: 6442812
    Abstract: A method of manufacturing a piezoelectric torque transducer is provided, comprising the steps of (a) forming a prepared area on a surface of a torsion member adapted to be strained by an applied torque; (b) providing a piezoelectric element having an axis of maximum strain sensitivity and disposing first and second electrodes on opposite faces of the element, respectively, and attaching an electrical lead to each electrode; (c) connecting electrical leads to the electrodes; and (d) disposing the element on the prepared area and orienting the axis of maximum strain sensitivity on the member and securing the element to the prepared area with a material selected from a group consisting of (i) adhesive material and (ii) potting material.
    Type: Grant
    Filed: March 2, 2000
    Date of Patent: September 3, 2002
    Assignee: Eaton Corporation
    Inventors: John A. Kovacich, Wayne S. Kaboord, Fred J. Begale, Robert R. Brzycki, Birger Pahl, James E. Hansen
  • Patent number: 6401542
    Abstract: A down-sized pressure sensing semiconductor device with improved EMI tolerance as compared with conventional ones is achieved. A metal substrate (11) has a through hole (12), in which a cylinder (9b) of a pressure leading-in tube (9) is inserted, and is fixed to a flange (9a) of the pressure leading-in tube (9). A control circuit component (13) for controlling a semiconductor chip (1) is disposed on the metal substrate (11). On the metal substrate (11), a connector electrode (14) is further provided which establishes electrical connections between the pressure sensing semiconductor device and external circuits. Further, a metal cover (17) in the shape of a connector leading to external circuits is soldered to the metal substrate (11) to cover the semiconductor chip (1) and the control circuit component (13) together with the metal substrate (11). The cover (17) is electrically connected to a conductive wire (e.g., a ground wire) formed on the metal substrate (11).
    Type: Grant
    Filed: July 11, 2000
    Date of Patent: June 11, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Hajime Kato
  • Patent number: 6393920
    Abstract: A sound pressure sensing device comprises a piezoelectric substrate, an input interdigital transducer, a first output interdigital transducer, a second output interdigital transducer, a diaphragm, a liquid tank, and a signal analyzer. All the input-, the first output-, and the second output interdigital transducers are formed on one end surface of the piezoelectric substrate. The liquid tank has a liquid in contact with the other end surface of the piezoelectric substrate and an inner surface of the diaphragm. If an input electric signal is applied to the input interdigital transducer, an elastic wave is excited in the piezoelectric substrate. A leaky component of the elastic wave is radiated effectively in the form of a longitudinal wave into the liquid. The longitudinal wave is reflected in the liquid by the diaphragm. A reflected longitudinal wave is detected at the first output interdigital transducer as a first delayed electric signal.
    Type: Grant
    Filed: April 21, 2000
    Date of Patent: May 28, 2002
    Inventor: Kohji Toda
  • Patent number: 6329825
    Abstract: A pressure detecting bridge circuit produces a sensor signal Sd. A temperature detecting bridge circuit produces a temperature signal St. A reference voltage generating circuit produces a reference signal Sa. An analog multiplexer processes these signals Sd, St and Sa in a time-divisional manner. A differential amplification circuit and an A/D conversion circuit are commonly used to obtain the digital data corresponding to the sensor signal Sd, the temperature signal St and the reference signal Sa. The temperature detecting bridge circuit includes reference resistance elements. By adjusting the design resistance values of the reference resistance elements, the variation width of the sensor signal Sd in a pressure measuring range of the pressure detecting bridge circuit is substantially equalized in advance with the variation width of the temperature signal St in a temperature measuring range of the temperature detecting bridge circuit.
    Type: Grant
    Filed: November 16, 1999
    Date of Patent: December 11, 2001
    Assignee: Denso Corporation
    Inventors: Hiroaki Tanaka, Inao Toyoda
  • Patent number: 6313514
    Abstract: The pressure sensor component has a chip carrier carrying a semiconductor chip with an integrated pressure sensor having a pressure-detecting surface exposed to the pressure to be measured. A device encapsulation made from an electrically insulating material surrounds the entire assembly except for protruding electrode terminals. Bond wires connect the electrode terminals with the pressure sensor and/or the electronic circuit of the semiconductor chip. The device encapsulation consists entirely of a homogeneous pressure-transmitting medium comprising an enveloping compound, which transmits the pressure to be measured as free from delay and attenuation as possible but is mechanically resistant and dimensionally stable. The pressure to be measured is transmitted directly by the enveloping compound onto the pressure-detecting surface of the semiconductor chip, and the pressure sensor and/or the pressure sensor component is covered tightly on all sides against mechanical and/or chemical influences.
    Type: Grant
    Filed: June 8, 1998
    Date of Patent: November 6, 2001
    Assignee: Infineon Technologies AG
    Inventors: Jürgen Winterer, Eric Bootz, Bernd Stadler, Achim Neu, Thies Janczek
  • Patent number: 6272928
    Abstract: A single chip dielectrically isolated leadless pressure sensor adapted to substantially simultaneously measure a first pressure and a differential between the first pressure and a second pressure including: a wafer including first and second recessed portions respectively defining first and second deflectable diaphragms and at least one rim portion formed between the first and second recessed portions for isolating the first deflectable diaphragm from the second deflectable diaphragm; a first circuit mounted on the first deflectable diaphragm and being responsive to the first pressure; and a second circuit mounted on the second deflectable diaphragm and being responsive to the second pressure; wherein, the first and second circuits are adapted to be electrically coupled to one another so as to cooperatively provide a common output indicative of a differential pressure associated with the first and second pressures, while simultaneously partially providing an output indicative of the first or second pressures.
    Type: Grant
    Filed: January 24, 2000
    Date of Patent: August 14, 2001
    Assignee: Kulite Semiconductor Products
    Inventor: Anthony D. Kurtz
  • Patent number: 6240785
    Abstract: A pressure sensor is provided for cryogenic, high pressure applications. A highly doped silicon piezoresistive pressure sensor is bonded to a silicon substrate in an absolute pressure sensing configuration. The absolute pressure sensor is bonded to an aluminum nitride substrate. Aluminum nitride has appropriate coefficient of thermal expansion for use with highly doped silicon at cryogenic temperatures. A group of sensors, either two sensors on two substrates or four sensors on a single substrate are packaged in a pressure vessel.
    Type: Grant
    Filed: December 10, 1996
    Date of Patent: June 5, 2001
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: John J. Chapman, Qamar A. Shams, William T. Powers
  • Patent number: 6229427
    Abstract: A method for sealing a transducer of a type having a diaphragm with an active region and an inactive region, a stress sensing network associated with the active region of the diaphragm, contacts associated with the inactive region of the diaphragm, and lead-outs for coupling the stress sensing network to the contacts. The method comprises oxidizing the transducer to provide a first oxide layer which covers the diaphragm, the stress sensing network, the lead-outs and the contacts. Next, a layer of semiconductive material is deposited over the first oxide layer and is then planarized to provide a planar surface having a substantially flat and bondable surface. Finally, a cover member is bonded to the planar surface of the layer which covers the inactive region of the diaphragm to hermetically seal the stress sensing network and thereby provide a sealed transducer.
    Type: Grant
    Filed: July 21, 1997
    Date of Patent: May 8, 2001
    Assignee: Kulite Semiconductor Products Inc.
    Inventors: Anthony D. Kurtz, Alexander A. Ned
  • Patent number: 6210989
    Abstract: There is disclosed a semiconductor sensor device comprising a semiconductor diaphragm member having a top surface coated with an oxide layer; P+ sensor elements fusion bonded to the oxide layer at a relatively central area of the diaphragm; P+ finger elements fusion bonded to the oxide layer extending from the sensors to an outer contact location of the diaphragm for each finger; and an external rim of P+ material fusion bonded to the oxide layer and surrounding the sensors and fingers. A first glass wafer member is electrostatically bonded at a bottom surface to the fingers and rim to hermetically seal the sensors and fingers of the diaphragm member.
    Type: Grant
    Filed: September 17, 1999
    Date of Patent: April 3, 2001
    Assignee: Kulite Semiconductor Products Inc.
    Inventors: Anthony D. Kurtz, Alexander Ned, Scott J. Goodman
  • Patent number: 6211772
    Abstract: A semiconductor composite sensor using a plurality of semiconductor piezoresistive gauge elements connected in series. The piezoresistive elements are separated so that a high potential terminal of one of the resistive elements having the same resistance values and the substrate of the other of the resistive elements will be connected with equal potential values. Potential difference values between semiconductor regions serving as respective resistive elements and the substrates are made equal.
    Type: Grant
    Filed: September 5, 1997
    Date of Patent: April 3, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Susumu Murakami, Satoshi Shimada, Seiichi Ugai, Yukio Takahashi, Shuichi Shimizu
  • Patent number: 6204086
    Abstract: A method for manufacturing semiconductor components having micromechanical structures, micromechanical structures being patterned in a wafer for detecting a physical quantity acting on micromechanical structures, and semiconductor components for converting the physical quantity into an electrical signal proportional to the physical quantity being produced. The semiconductor components and the micromechanical structures are defined in a self-aligning manner by process steps acting on one side of the wafer to produce semiconductor components.
    Type: Grant
    Filed: March 11, 1998
    Date of Patent: March 20, 2001
    Assignee: Robert Bosch GmbH
    Inventors: Joerg Muchow, Helmut Baumann
  • Patent number: 6201467
    Abstract: The pressure sensor component has a chip carrier with an approximately planar chip carrier surface. A semiconductor chip with an integrated pressure sensor is placed on the chip carrier surface. A pressure-detecting surface area of the pressure sensor is exposed to a pressure to be measured. The component is encapsulated with electrically insulating material that encloses the semiconductor chip and/or the chip carrier at least in regions. A chimney-shaped connection piece that projects up relative to the pressure-detecting area of the pressure sensor penetrates through the encapsulation and is connected to the pressure sensor. The connection piece, which is a separate structural element is incorporated in the component encapsulation and it encloses at least the pressure-detecting surface area in a pressure-tight manner with its end bearing on the semiconductor chip. The connection piece is open toward the outside at its opposite end so as to expose the pressure sensor to the pressure to be measured.
    Type: Grant
    Filed: August 25, 1999
    Date of Patent: March 13, 2001
    Assignee: Infineon Technologies AG
    Inventors: Jürgen Winterer, Eric Bootz, Bernd Stadler, Achim Neu, Thies Janczek
  • Patent number: 6198379
    Abstract: A circuit arrangement implemented as an integrated semiconductor component has a measured value acquisition circuit that can be connected to an analysis circuit, in particular a piezoresistive measuring bridge containing piezoresistive measuring shunts diffused on a semiconductor substrate. The piezoresistive measuring shunts are connected to metallic terminal contacts by diffused terminal resistors having a negligible piezoresistive resistance. To avoid terminal-related offset errors on the measuring shunts in particular, the terminal resistors are designed as identical, elongated, generally curved area structures that taper toward the front end and are connected to a measuring shunt on the front end and to a metallic terminal contact on the opposite end.
    Type: Grant
    Filed: June 11, 1998
    Date of Patent: March 6, 2001
    Assignee: Robert Bosch GmbH
    Inventor: Oliver Schatz
  • Patent number: 6177727
    Abstract: A semiconductor component (31) and a method for coupling a semiconductor device (36) to a substrate (81). The semiconductor component (31) includes a saddle (34) and the semiconductor device (36). The saddle (34) has a plurality of sides (51, 52, 53, 54, 55) that form a semiconductor device receiving area (58). The semiconductor device (36) is inserted into the semiconductor device receiving area (58) and secured in the semiconductor device receiving area (58) using tabs (66, 67). The saddle (34) is coupled to the substrate (81) by fasteners (82,83).
    Type: Grant
    Filed: May 1, 1998
    Date of Patent: January 23, 2001
    Assignee: Motorola, Inc.
    Inventors: John W. Hart, Jr., William G. McDonald, Daniel John Wallace, Jr.
  • Patent number: 6150681
    Abstract: A monolithic, integrated circuit sensor combining both a differential pressure sensor and a flow sensor on the same silicon chip. The integrated circuit has a diaphragm with a number of piezo-resistive elements placed on it in the normal manner for a pressure sensor. In addition, a channel is provided between the spaces on the two sides of the diaphragm. The channel has a cross-section which is a fraction of the size of the diaphragm. In one embodiment, the channel is a hole in the diaphragm. In another embodiment, the channel is an etched groove in the frame supporting the diaphragm.
    Type: Grant
    Filed: July 24, 1998
    Date of Patent: November 21, 2000
    Assignee: Silicon Microstructures, Inc.
    Inventor: Henry V. Allen
  • Patent number: 6148673
    Abstract: A differential pressure sensor (10) has a sensor die (30) eutectically attached to a mounting flag (14). The mounting flag has a similar coefficient of thermal expansion to the sensor die. The eutectic attachment provides a hermetic seal between the mounting flag and the sensor die. Pressure is applied to sensor die port (20). A molded housing (12) is molded around the sensor die-mounting flag assembly. Port (22) in the molded housing is filled with a silicone gel (52). A second pressure source is transferred by way of the silicone gel to the sensor die. Any media entering port (20) contacts the first surface of the sensor die to assert pressure against a piezoresistive transducer circuit (32) to generate the electrical signals representative of the applied pressure but are isolated from the sensitive interconnects by the hermetic seal.
    Type: Grant
    Filed: October 7, 1994
    Date of Patent: November 21, 2000
    Assignee: Motorola, Inc.
    Inventor: Clem H. Brown
  • Patent number: 6131466
    Abstract: The pressure sensor is integrated in an SOI (Silicon-on-Insulator) substrate using the insulating layer as a sacrificial layer, which is partly removed by chemical etching to form the diaphragm. To fabricate the sensor, after forming the piezoresistive elements and the electronic components integrated in the same chip, trenches are formed in the upper wafer of the substrate and extending from the surface to the layer of insulating material; the layer of insulating material is chemically etched through the trenches to form an opening beneath the diaphragm; and a dielectric layer is deposited to outwardly close the trenches and the opening. Thus, the process is greatly simplified, and numerous packaging problems eliminated.
    Type: Grant
    Filed: July 30, 1997
    Date of Patent: October 17, 2000
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Benedetto Vigna, Paolo Ferrari, Flavio Villa
  • Patent number: 6117086
    Abstract: A physiological pressure transducer is disclosed which can be adapted for multiple uses and which employs a low cost semiconductor strain gauge sensor. The transducer is connected to a fluid-filled catheter/manometer system for measuring pressures inside a living body in areas of medical interest such as the heart, brain, uterus, or the vascular system. The catheter is coupled to the pressure transducer through a unique, disposable dome containing a shaped, compliant isolation media which is in intimate contact with the transducer diaphragm. The complete assembly is adapted for use with standard catheter flushing solutions and flush devices. An improved method of drawing blood samples by using the features of the assembly is also described.
    Type: Grant
    Filed: April 18, 1997
    Date of Patent: September 12, 2000
    Assignee: Sunscope International, Inc.
    Inventor: John E. Shulze
  • Patent number: 6076408
    Abstract: A pressure in a pressurizing chamber of a micromachine apparatus for transferring a fluid is measured inexpensively under an actual-use or a similar condition. A piezoelectric element used as an actuator for applying a pressure to the fluid in the pressurizing chamber is also used as a pressure sensor. A charge amplifier is used to measure the amount of charge Q.sub.1 applied to an electrode of the piezoelectric element when the piezoelectric element is driven while the pressurizing chamber filled with the fluid, and the amount of charges Q.sub.2 when the piezoelectric element is driven while the chamber contains no fluid. The obtained signals are inputted to a storage and operation processing device to determine (Q.sub.1 -Q.sub.2) to determine the pressure of the fluid in the pressurizing chamber. The piezoelectric element or capacitor for the purposes of comparison can be used to simultaneously measure Q.sub.1 and Q.sub.2.
    Type: Grant
    Filed: April 7, 1998
    Date of Patent: June 20, 2000
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Takeshi Matsubara, Yujiro Kitaide
  • Patent number: 6070469
    Abstract: A pressure sensor includes a body, a pressure inlet tube housed in the body and having a pressure inlet opening defined therein for introducing oil pressure, and a pressure sensor unit affixed to a proximal end surface of the pressure inlet tube covering the pressure inlet opening to convert the oil pressure to an electrical signal. An oil flow decelerating structure is disposed to a distal end side of the pressure inlet tube for reducing the flow rate of oil.
    Type: Grant
    Filed: September 9, 1998
    Date of Patent: June 6, 2000
    Assignee: Matsushita Electric Works, Ltd.
    Inventors: Naohiro Taniguchi, Shuichi Katayama, Masami Hori
  • Patent number: 6062088
    Abstract: A pressure sensor includes a metallic membrane and a frame. For detecting the deflection of the membrane, a silicon bridge element having piezoresistive resistor elements is arranged on the membrane and the frame.
    Type: Grant
    Filed: March 3, 1999
    Date of Patent: May 16, 2000
    Assignee: Robert Bosch GmbH
    Inventors: Kurt Ingrisch, Kurt Weiblen, Hubert Benzel, Botho Ziegenbein, Hans-Peter Trah, Andreas Duell, Karl Bender, Jochen Franz
  • Patent number: 6044711
    Abstract: A sensing apparatus having a body member with a portion engageable with a work object having a medium to be sensed; and a system for registering at predetermined criterion, relative to the body member, during engagement of the portion of the body member with the work object, as an index of the medium. A method for manufacturing a resultant work piece having at least one projection thereon, the method including the steps of cutting a first work material to form the projection on a portion of the first work material, mounting the projection on a second work material and removing the remainder of the first work material from the projection to form the resultant work piece.
    Type: Grant
    Filed: January 10, 1997
    Date of Patent: April 4, 2000
    Assignee: PSI-Tronix, Inc.
    Inventor: William L. Bubel
  • Patent number: 6023978
    Abstract: A pressure transducer that includes at least two sensors having substantially similar or substantially identical error characteristics, wherein each sensor is arranged to be subjected to an applied pressure and the outputs of the sensors are electrically coupled so that errors associated with one sensor are compensated by errors associated with the other sensor. The sensors may be substantially identical silicon sensors formed in close proximity on the same wafer.
    Type: Grant
    Filed: July 10, 1997
    Date of Patent: February 15, 2000
    Assignee: Honeywell Data Instruments, Inc.
    Inventors: Dennis Dauenhauer, Dale Dauenhauer, Alexander Breitenbach, Herman Erichsen
  • Patent number: 6021675
    Abstract: A force transducer having a semiconductor substrate including a surface defining a recess, such that the recess has a peripheral boundary and a flexible diaphragm connected to the surface along the peripheral boundary to enclose the recess so that the diaphragm moves in response to changes in a force applied thereto. The force transducer also includes a resonant beam connected to the surface adjacent the peripheral boundary. The resonant beam has a frequency of resonation. Movement of the diaphragm in response to changes in the force applied to the diaphragm changes the frequency of resonation of the resonant beam.
    Type: Grant
    Filed: February 28, 1997
    Date of Patent: February 8, 2000
    Assignee: SSI Technologies, Inc.
    Inventors: James D. Seefeldt, Michael F. Mattes
  • Patent number: 6003381
    Abstract: A pressure sensor including a pressure sensor element, a pedestal having a through-hole defined therein for guiding an external pressure to the pressure sensor element and a header, all of which are successively tightly bonded together. The pressure sensor also includes a cap for covering the pressure sensor element and the pedestal and mounted tightly on the header. A region of the header ranging from a joint between the cap and the header to a joint between the pedestal and the header is stepped.
    Type: Grant
    Filed: March 29, 1999
    Date of Patent: December 21, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Hajime Kato
  • Patent number: 5969591
    Abstract: A single-sided differential pressure sensing chip having a cavity formed in the top surface of a substrate, a deformable diaphragm spanning the cavity, and a pressure passage connecting the top surface of the substrate with the cavity, and a method of making the same are described. A first fluid pressure applied to the top surface of the substrate in the vicinity of the diaphragm exerts a force on the top surface of the diaphragm, and a second fluid pressure applied to the top surface of the substrate near the pressure passage exerts a force on the bottom surface of the diaphragm. The diaphragm deflects in response to the forces exerted upon it, and a sensing element detects the flexing of the diaphragm. The pressure sensing chip can be contained within a housing structure formed of a carrier and a cap.
    Type: Grant
    Filed: June 3, 1996
    Date of Patent: October 19, 1999
    Assignee: The Foxboro Company
    Inventor: Clifford D. Fung
  • Patent number: 5946642
    Abstract: An air data measurement system includes a device for sensing air pressure outside an aircraft, a pressure transducer in fluid communication with the air pressure sensing device and having a piezoresistive bridge attached on a flexible diaphragm. The piezoresistive bridge has an electrical resistance which varies in response to the sensed air pressure applied to the diaphragm and whose sensitivity varies with the magnitude of the excitation current passing therethrough. The system also includes a current supply operatively connected to the pressure transducer for supplying and varying the magnitude of the excitation current to the piezoresistive bridge. Further included is an output device connected to the pressure transducer for sensing a change in the electrical resistance of the piezoresistive bridge and outputting a signal from the piezoresistive bridge corresponding to the sensed air pressure.
    Type: Grant
    Filed: March 20, 1998
    Date of Patent: August 31, 1999
    Assignee: Innovative Solutions & Support Inc.
    Inventor: Geoffrey S.M. Hedrick
  • Patent number: 5902248
    Abstract: A device that contemplates a unique and advantageous reduced size catheter tip measurement device. By using a bottom support member and a thin outer insulating layer, rather than a tubular metal casing, to support and isolate the electrical measurement sensor, the present invention drastically reduces feature size possible with current structures for catheter tip measurement devices. More specifically, the device contemplates a reduced size catheter tip pressure transducer device. The device includes a catheter body that has a support member attached to its distal tip. The support member has a support surface for a semiconductor pressures sensor that provides mechanical stability to the pressure sensor. The exposed electrical and metal areas of the device are insulated from surrounding tissues and fluids by an outer insulating layer, which is preferably a polyimide sleeve.
    Type: Grant
    Filed: November 6, 1996
    Date of Patent: May 11, 1999
    Assignee: Millar Instruments, Inc.
    Inventors: Huntly D. Millar, Richard Alan Smith
  • Patent number: 5895859
    Abstract: A pressure sensor comprises two sensor, a casing and a filter. A first sensor is a suction air pressure sensor for measuring the pressure of the air sucked in an internal combustion engine and the like. A second sensor is an atmospheric pressure sensor for measuring the atmospheric pressure. The casing accommodates the suction air pressure sensor and the atmospheric pressure sensor. The filter prevents the infiltration of solid matter and liquid form outside of the puressure sensor, and is mounted on the air introducing part of the atmospheric pressure sensor in the casing.
    Type: Grant
    Filed: July 30, 1997
    Date of Patent: April 20, 1999
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Kenichi Sawada, Tateki Mitani
  • Patent number: 5889212
    Abstract: A single, disposable differential transducer having a molded plastic body in which there is a pair of chambers separated by a strain gage electronic chip that flexes in accordance with the difference in the pressures between the two chambers. The plastic housing has inlets to allow communication with the chambers and the overall unit is readily manufactured of inexpensive components that allow disposability of the unit when it has been used on a patient. The pressure transducer chambers are isolated from each other such that differing locations of the patient may be sensed for pressure at the same time without the risk of inadvertant cross-contamination.
    Type: Grant
    Filed: October 31, 1997
    Date of Patent: March 30, 1999
    Assignee: Becton Dickinson and Company
    Inventors: Robert Guthrie, John Yan, Rene Luigies
  • Patent number: 5880373
    Abstract: An arrangement for measuring high pressure differences. The arrangement has a differential pressure sensor made using thin film technology. The arrangement has a metallic layer in which measuring resistors are arranged. The sensitive structures of the measuring resistors are kept away from aggressive measuring media by encapsulation.
    Type: Grant
    Filed: July 22, 1998
    Date of Patent: March 9, 1999
    Assignee: Hartmann & Braun GmbH & Co. KG
    Inventor: Klaus-Dieter Barton
  • Patent number: 5861558
    Abstract: A pressure sensor has resistive elements for measuring strain on the surface of a diaphragm. Each resistive element has first and second metallic pads with at least two lines of piezoresistive material formed between the pads, each exhibiting a high length to width aspect ratio. The pressure gauge may be of a one piece, cup-shaped construction having a diaphragm forming the floor of the cup. The internal diameter of the cup is less than 10 mm, and piezoresistive, thick film elements are formed on the inside surface of the diaphragm. The piezoresistive elements may be formed using a pen to trace a pattern of resistive ink on the substrate surface, using a stencil or using electrostatic spraying of the resistive ink onto the substrate surface.
    Type: Grant
    Filed: February 27, 1997
    Date of Patent: January 19, 1999
    Assignee: Sigma-Netics, Inc.
    Inventors: Timothy R. Buhl, Steve Soos
  • Patent number: 5859759
    Abstract: The semiconductor pressure sensor has a pressure sensor unit with a pressure sensor chip for detecting pressure, peripheral circuitry for converting the pressure detected by the pressure sensor unit to an electrical signal and processing the electrical signal, a lead frame for fastening and electrically connecting peripheral circuitry, a package in which the peripheral circuitry and lead frame are integrated in a resin molding including a cavity in which the pressure sensor unit is housed, a cover for closing the opening of the cavity in which the pressure sensor unit is housed, and a pressure opening for conveying a pressure-conveying medium to the pressure sensor chip. The pressure sensor unit is fastened to the inside bottom of the cavity and is electrically connected to a particular part of the lead frame exposed inside the cavity.
    Type: Grant
    Filed: March 18, 1997
    Date of Patent: January 12, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kyoichi Moriyama, Katsumi Sakabe, Motomi Ichihashi
  • Patent number: 5854421
    Abstract: A semiconductor sensor having a semiconductor sensor chip with a diaphragm on which a bridge circuit is formed with piezoresistances has a resistor for adjusting an offset of the bridge circuit wherein an adjustment is done to equalize an output voltage of the sensor at the upper operating limit temperature to that at the lower operating limit temperature by trimming the resistor.
    Type: Grant
    Filed: October 11, 1996
    Date of Patent: December 29, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Masahiro Yamamoto
  • Patent number: 5848971
    Abstract: A medical pressure transducer includes a reusable component with channels to either side of a reusable diaphragm, and a disposable dome with mounting wings to either side of a disposable diaphragm and slidably receivable in the channels to mount the dome with the diaphragms in confronting relationship. Camming ramps are provided in the channels and on the wings by which to drive the dome diaphragm into the reusable diaphragm. Where the channels are defined behind outer front walls, the outer surface of one is provided with a tab-receiving slot to receive a locking tab associated with dome to lock diaphragms into confronting relationship. The dome includes second wings spaced from the mounting wings to receive the outer front walls. The second wings have finger gripping portions one of which is a locking paddle supporting the lock tab. In alternative embodiments, the dome wings are edges, fixed or resilient, receivable through slots formed in the reusable component.
    Type: Grant
    Filed: April 11, 1997
    Date of Patent: December 15, 1998
    Assignee: Medex, Inc.
    Inventors: James H. Fowler, Charles R. Patzer, Warren B. Nicholson, Wendell Thompson, Glenn D. Brunner, Theodore R. Adams, Nilesh M. Shah
  • Patent number: 5783750
    Abstract: A semiconductor sensor includes a circuit board; a pedestal including stacked board-composing materials arranged sequentially on the circuit board and describing a mesh shape on the circuit board, the mesh shape including at least one central opening in which the circuit board is exposed; and a sensing element fixed to and supported on the pedestal as a cantilever.
    Type: Grant
    Filed: October 10, 1996
    Date of Patent: July 21, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Hiroshi Otani
  • Patent number: 5774056
    Abstract: An indicating device includes a housing that is separated into two sub-chambers by a flexible diaphragm. A indicating member is carried by the diaphragm so that the diaphragm and the indicating member move, within the housing, responsively to changes in the pressure of the air flowing through an air intake system caused by restrictions in or clogging of the air intake filter. The indicating device incorporates an electromechanical sensor for monitoring the position of the diaphragm and producing an output signal responsive thereto. In one embodiment, the sensor is a potentiometer which produces an output signal which varies continuously between a first value when the diaphragm is at its unrestricted position and a second value when the diaphragm is at its restricted position. In a second embodiment, the sensor includes a switching circuit which produces a switched output signal which varies between at least three states corresponding to three different diaphragm positions.
    Type: Grant
    Filed: May 30, 1996
    Date of Patent: June 30, 1998
    Assignee: Engineered Products Co.
    Inventors: Charles Henry Berry, III, Jerry Lee Manross, Thomas Alan Stoll, Gregory Matthew Ferris, James Nathan Forry
  • Patent number: 5756904
    Abstract: A circuit and various sensor arrays are provided which facilitate the scanning of an array of pressure responsive points at higher speed than is possible with currently available circuits and sensor arrays and also provides greater flexibility in selecting scanning speed and in making a tradeoff between scanning speed and resolution. These objectives are achieved by providing a sensor array having T sets of drive electrodes, with pressure points in a predetermined pattern intersected by drive electrodes of each set and a sense electrode for each pressure point of a set.
    Type: Grant
    Filed: August 30, 1996
    Date of Patent: May 26, 1998
    Assignee: Tekscan, Inc.
    Inventors: Boris Oreper, Paul Howard
  • Patent number: 5752918
    Abstract: A medical pressure transducer includes a reusable component with channels to either side of a reusable diaphragm, and a disposable dome with mounting wings to either side of a disposable diaphragm and slidably receivable in the channels to mount the dome with the diaphragms in confronting relationship. Camming ramps are provided in the channels and on the wings by which to drive the dome diaphragm into the reusable diaphragm. Where the channels are defined behind outer front walls, the outer surface of one is provided with a tab-receiving slot to receive a locking tab associated with dome to lock diaphragms into confronting relationship. The dome includes second wings spaced from the mounting wings to receive the outer front walls. The second wings have finger gripping portions one of which is a locking paddle supporting the lock tab. In alternative embodiments, the dome wings are edges, fixed or resilient, receivable through slots formed in the reusable component.
    Type: Grant
    Filed: June 28, 1995
    Date of Patent: May 19, 1998
    Assignee: Medex, Inc.
    Inventors: James H. Fowler, Charles R. Patzer, Warren B. Nicholson, Wendell Thompson, Glenn D. Brunner, Theodore R. Adams, Nilesh M. Shah
  • Patent number: 5750898
    Abstract: A method for passivating diamond films to substantially prevent them from oxidizing at temperatures up to 800.degree. C. in an oxygen atmosphere. The method involves depositing one or more passivating layers over the diamond film wherein one of the layers is nitride and the other layer is quartz. The passivation technique is directly applicable to diamond sensor pressure transducers and enable them to operate at temperatures above 800.degree. C. in oxygen environments. The passivation technique also provides an economical and simple method for patterning diamond films.
    Type: Grant
    Filed: October 9, 1996
    Date of Patent: May 12, 1998
    Assignee: Kulite Semiconductor Products, Inc.
    Inventors: Anthony D. Kurtz, Alexander A. Ned, Timoteo I. Vergel de Dios
  • Patent number: 5744719
    Abstract: The integrated micromechanical sensor device contains a body with a substrate (1) on which an insulating layer (2) and thereon a monocrystalline silicon layer (3), are arranged, in which the silicon layer has trenches as far as the surface of the insulating layer, and the side walls of the trenches as well as the side of the silicon layer adjacent to the insulating layer have a first doping type (n.sup.+) and the silicon layer has a second doping type (n.sup.-) at least in a partial region of its remaining surface, in which the silicon layer has a transistor arrangement in a first region (TB) and a sensor arrangement in a second region (SB), for which the insulating layer (2) is partly removed under the second region. Such a sensor device has considerable advantages over known devices with regard to its properties and its production process.
    Type: Grant
    Filed: June 12, 1996
    Date of Patent: April 28, 1998
    Assignee: Siemens Aktiengesellschaft
    Inventor: Wolfgang Werner
  • Patent number: 5742222
    Abstract: An economical non-metallic strain gage insensitive to ambient temperature variations, and without a diode junction, which is suitable for general use and particularly for use in touch screens, wherein the gage is adapted to be directly adhered to the screen. The gage is metallized with a thin layer of a solderable metal for electrical soldering connection to strain measurement devices and for reliable mechanical support. The gage includes an etched polysilicon material on a substrate base, such as a silicon wafer, wherein the polysilicon is doped with a dopant material such that output measurements are independent of temperature changes.
    Type: Grant
    Filed: May 26, 1995
    Date of Patent: April 21, 1998
    Assignee: AVI Systems, Inc.
    Inventors: Thomas M. Young, Pierre R. Irissou
  • Patent number: 5714690
    Abstract: A form pressure sensor diaphragm and method of making that allows for formation of long rectangular plate structures in semiconducting materials, especially silicon. A plurality or multiplicity of sensors may be constructed on a single chip, thus providing for absolute and relative sensing of pressure on a single device.
    Type: Grant
    Filed: August 9, 1996
    Date of Patent: February 3, 1998
    Assignee: Honeywell Inc.
    Inventors: David W. Burns, Max C. Glenn
  • Patent number: 5691478
    Abstract: A device and method for remotely zeroing a hydrostatic pressure compensation device are described which permit a fluid transducer, such as is used in conjunction with an intravenous catheter for the measurement of blood pressure, to be zeroed regardless of its elevation. A hydrostatic pressure compensation tube is placed in closed fluid communication with both faces of the transducer so as to provide the same pressure to each side. As an example, the transducer may measure the deflection with a piezoresistive or piezoelectric crystal or may alternatively utilize a semiconductor membrane with implanted resistive elements. The transducer may be coupled or formed integral to a manifold. In such a device, the transducer may be zeroed at any vertical position.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: November 25, 1997
    Assignee: Schneider/Namic
    Inventors: Robert L. Barry, Robert F. Alexander
  • Patent number: 5683594
    Abstract: This patent relates to the fabrication of diaphragm-based microstructures used primarily for sensing physical phenomena by detecting a change in deflection, resonance, or curvature of the diaphragm. The methods of fabrication described and claimed herein relate primarily to diaphragm-based diaphragms made of silicon, either single crystal or polycrystalline in form, although other materials may be used.
    Type: Grant
    Filed: March 24, 1994
    Date of Patent: November 4, 1997
    Assignee: Honeywell, Inc.
    Inventors: G. Benjamin Hocker, David W. Burns, Akintunde I. Akinwande, Robert D. Horning, Amir R. Mirza, Thomas G. Stratton, Deidrich J. Saathoff, James K. Carney, Scott A. McPherson