With Protective Separator Patents (Class 73/706)
  • 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: 5894093
    Abstract: An improved closure for a pressure gauge includes a stem or a sleeve which selectively provides a vent path when set by the end user. The closure device provides an automatic venting if in the normally closed condition by means of an overpressure valve arrangement in the sleeve. Therefore the two functions are incorporated in the single closure device.
    Type: Grant
    Filed: May 12, 1995
    Date of Patent: April 13, 1999
    Assignee: Dresser Industries, Inc.
    Inventors: Walter J. Ferguson, Albert V. Yannella
  • Patent number: 5892156
    Abstract: Pressure or force measurement device for static or dynamic pressure measurement, in particular for high pressures or forces, having a housing including a pressure or force measuring cell, e.g., a piezoresistive or capacitive measuring cell. In such devices, service life and chemical resistance are problematic. The pressure measurement device includes the housing, a seal between the pressure medium and an inner chamber of the housing, a pressure measuring cell having a main face exposed to the pressure medium and which pressure measuring cell having a deflection when pressure loaded, which deflection leads to a relative movement between the pressure measuring cell and the housing in a region of the seal. In a region of the seal, the housing has spring-elastic properties. The pressure measurement device further includes a flange with an elastic sealing rib forming a through opening. The housing may be rotationally symmetrical with respect to the flange.
    Type: Grant
    Filed: January 23, 1998
    Date of Patent: April 6, 1999
    Assignee: IFM Electronic GmbH
    Inventors: Benno Kathan, Jorg Schutze
  • Patent number: 5889211
    Abstract: A media compatible microsensor structure (11) for sensing an environmental condition in a harsh media includes an inorganic protective film (17) covering portions of the structure that will be exposed to the harsh media. In one embodiment, the microsensor structure (11) includes a microsensor package (12), a microsensor device (16) bonded to the microsensor package (12), a leadframe (13), a connective wire (14) connecting the microsensor device (16) to the leadframe (13), and an inorganic protective film (17) formed on all or portion of the exposed surfaces of the structure.
    Type: Grant
    Filed: April 3, 1995
    Date of Patent: March 30, 1999
    Assignee: Motorola, Inc.
    Inventors: Theresa A. Maudie, David J. Monk, Timothy S. Savage
  • Patent number: 5874679
    Abstract: A pressure sensor package and method for producing the same. The package includes a pressure sensor base, a pressure sensor diaphragm positioned over the pressure sensor base, and a pressure sensor cap positioned over the pressure sensor diaphragm and secured relative to the pressure sensor base such that a portion of the pressure sensor diaphragm is deformed between the pressure sensor cap and the pressure sensor base. The deformation can occur along a line of deformation, preferably to form a closed path adjacent a periphery of the pressure sensor diaphragm. In one embodiment, the pressure sensor diaphragm is deformed between an inner surface of the pressure sensor cap and an outer surface of the pressure sensor base along the line of deformation, and the inner surface and the outer surface diverge from each other when moving away from the line of deformation.
    Type: Grant
    Filed: April 4, 1996
    Date of Patent: February 23, 1999
    Assignee: SSI Technologies, Inc.
    Inventor: Erick L. Sokn
  • Patent number: 5869766
    Abstract: A non-contaminating pressure transducer module having an isolation member is disclosed. The isolation member isolates a pressure sensor within the transducer module from exposure to ultra high purity fluids flowing through a conduit in the module without significantly affecting the accuracy of the pressure measurement. The transducer module may be positioned within a fluid flow circuit carrying corrosive materials, wherein the pressure transducer module produces a control signal proportional to either a gauge pressure or an absolute pressure of the fluid flow circuit. The pressure transducer module of the present invention also avoids the introduction of particulate, unwanted ions, or vapors into the flow circuit.
    Type: Grant
    Filed: December 1, 1997
    Date of Patent: February 9, 1999
    Assignee: NT International, Inc.
    Inventors: Gerald R. Cucci, Diane L. Englund
  • Patent number: 5869765
    Abstract: A dual seal coupling fitting enables quick measurement of pressure. The fitting includes primary and secondary valves and has one end shaped like a male portion of a quick coupler and another end screwable into a threaded bore defined in a pressure bearing housing. The fitting defines first and second cylindrical sections in communication with each other. The primary valve situates in the first section, the secondary valve in the second section. The primary valve includes a valve stem with a poppet head. A first mechanism compresses the poppet head against an outer valve seat to close the primary valve thereby preventing leakage of pressure. The secondary valve features a cylindrical seat piece and a retainer. The piece secures within the second section and defines through itself an inner bore. The piece at one end forms an inner valve seat and at an opposite end situates adjacent the first mechanism. The retainer has at one end a post approximate a terminal end of the valve stem within the inner bore.
    Type: Grant
    Filed: July 28, 1997
    Date of Patent: February 9, 1999
    Assignee: Westinghouse Air Brake Company
    Inventors: Daniel G. Scott, Gregory L. Johnston, Michael Veltri
  • Patent number: 5852244
    Abstract: A non-contaminating pressure transducer module having an isolation member is disclosed. The isolation member isolates a pressure sensor within the transducer module from exposure to fluids flowing through a conduit in the module. The transducer module may be positioned in-line within a fluid flow circuit carrying corrosive materials, wherein the pressure transducer module produces a control signal proportional to either a gauge pressure or an absolute pressure of the fluid flow circuit. The pressure transducer module of the present invention also avoids the introduction of particulate, unwanted ions, or vapors into the flow circuit.
    Type: Grant
    Filed: December 1, 1997
    Date of Patent: December 22, 1998
    Assignee: NT International, Inc.
    Inventors: Diane L. Englund, Gerald R. Cucci
  • Patent number: 5850778
    Abstract: Cookers working with an increasing internal pressure require a pressure indicator which can also adjust the internal pressure to a certain extent and, especially in the event of excessively high internal pressure, to release it by pressure equalization with the environment. Such pressure indicators consist of many parts and are complicated and not easily handlable for cleaning purposes. The invention proposes a pressure indicator which may consist of only a single component (2) besides the pressure indicator pin (1), being made of an elastic material and is multifunctional.
    Type: Grant
    Filed: July 24, 1997
    Date of Patent: December 22, 1998
    Assignee: Heinrich Baumgarten KG
    Inventor: Wolfgang Fischbach
  • 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: 5847282
    Abstract: An improved piezoresistive pressure sensor or an improved piezoresistive pressure pickup having a pressure measuring cell (13), a transmission diaphragm housing (7), which comprises a jacket housing section, a transmission diaphragm (17) and a backplate (21) and having a fluid pressure chamber (19) situated on the measuring diaphragm side is distinguished by the following featuresthe jacket housing section of the transmission diaphragm housing (7) comprises a pressure chamber sleeve (33),the pressure chamber sleeve (33) and the backplate (21) consists of weldable steel,the transmission diaphragm housing (7) and thus the pressure chamber sleeve (33) are or can be inserted in an annular recess (31) in the connection housing (3) in a sealing manner,the connection housing (3) consists of a material which cannot be welded or cannot easily be welded, andthe pressure chamber sleeve (33) and the backplate (21) are permanently welded in a sealing manner so as to seal off the pressure transmission medium provided in th
    Type: Grant
    Filed: October 16, 1996
    Date of Patent: December 8, 1998
    Assignee: Keller AG Fur Druckmesstechnik
    Inventor: Hans W. Keller
  • Patent number: 5834652
    Abstract: In a pressure sensing device, a sensor housing container is provided with a flange-like mounting portion to be attached to a medium container made of a thin plate by a bolt. The flange-like mounting portion has a mounting plane of said sensor housing container and is formed to have a great thickness enough to provide high rigidity. At the mounting plane, there are provided an opening through which a nipple of said pressure sensor protrudes from the sensor housing container and a concave plane on its periphery. A sealing member of elastic material is caused to intervene between the flange-like mounting portion and the medium container. The sealing member is integrally molded in a first space formed between an inner wall of the opening and an outer wall of the nipple and a second space communicating with the first space and formed by the concave plane when the sensor housing container is mounted on the medium container.
    Type: Grant
    Filed: November 24, 1997
    Date of Patent: November 10, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Akira Koshimizu
  • Patent number: 5831170
    Abstract: A pressure sensor package and a method of producing the same. The package includes a pressure sensor base, a pressure sensor diaphragm positioned over the base, and a sealing ring positioned over the pressure sensor diaphragm and creating an interference fit with the pressure sensor base. The sealing ring forms a mechanical interference with the pressure sensor base by either positioning the ring within an under cut in a sidewall of the base or deforming a portion of the base over the top of the ring. The pressure sensor base includes a recess having a bottom surface and a groove in the bottom surface, and the sealing ring and/or the pressure sensor diaphragm is positioned within the groove. The package further includes external threads for securing the package to a threaded orifice, the external threads being positioned on the output side of the package, as defined by the diaphragm.
    Type: Grant
    Filed: April 4, 1996
    Date of Patent: November 3, 1998
    Assignee: SSI Technologies, Inc.
    Inventor: Erick L. Sokn
  • Patent number: 5824909
    Abstract: The invention relates to pressure measurement apparatuses and pressure or force measurement devices for static or dynamic pressure measurement, in particular for high pressures or forces, whose housing contains among other things, a pressure or force measuring cell, e.g. a piezoresistive or capacitive measuring cell. In devices like this, service life and chemical resistance are problematic. The pressure measurement device according to the invention is essentially comprised of a housing (2), a seal (4) between the pressure medium and the inner chamber (2d) of the housing (2), a pressure measuring cell (3), whose first main face (3e) is exposed to the pressure medium and which has a deflection when pressure loaded, which deflection leads to a relative movement between pressure measuring cell (3) and housing (2) in the region of the seal (4). In the region of the seal (4), the housing (2) is embodied so that it has spring-elastic properties.
    Type: Grant
    Filed: August 2, 1996
    Date of Patent: October 20, 1998
    Assignee: IFM Electronic GmbH
    Inventors: Benno Kathan, Jorg Schutze
  • Patent number: 5811684
    Abstract: A method of securing a pressure sensor diaphragm to a pressure sensor base, including the steps of positioning the pressure sensor diaphragm over the pressure sensor base, placing a pressure sensor cap over the pressure sensor diaphragm, applying a tensile force to at least a portion of the cap, and deforming a portion of the cap around a portion of the base. The applying step can occur before the deforming step by engaging a portion of the cap and advancing the base toward the cap to create tension in a portion of the cap. This creates a tensile preload in the cap. The applying step can instead be performed during the deforming step by engaging a first portion of the cap and advancing a second portion of the cap toward the first portion of the cap and around a portion of the base. This can create tension in a portion of the cap when the deformation operation is being performed.
    Type: Grant
    Filed: October 10, 1996
    Date of Patent: September 22, 1998
    Assignee: SSI Technologies, Inc.
    Inventor: Erick Lee Sokn
  • Patent number: 5804736
    Abstract: A pressure transducer having a redundant fluid pressure sensor can be used to determine if the pressure transducer needs to be recalibrated. The pressure transducer comprises a fluid pressure sensor for measuring differential pressure. The fluid pressure sensor includes a pair of substantially identical pressure sensors for providing a variable electrical output as a function of a differential fluid pressure and a reference sensor for providing an electrical output independent of the differential fluid pressure. A conditioning circuit is provided for generating a frequency-based signal whose frequency is a function of the electrical output for each fluid pressure sensor. The electrical output of the first and second pressure sensors can be compared to determine whether the pressure transducer needs to be calibrated. In one embodiment, the pressure sensors comprise variable capacitors.
    Type: Grant
    Filed: January 27, 1997
    Date of Patent: September 8, 1998
    Assignee: Moore Products Co.
    Inventors: Philip R. Klauder, James O. Moore, Christopher J. O'Brien
  • Patent number: 5804735
    Abstract: A differential pressure transducer unit with an overload protection system to measure slight differential pressure in liquids and gases under high static compression loading, which unit can be connected by flanges to the differential-pressure lines. In order to reduce the number of pressure-tight electrical bushings and largely to dispense with continuously stressed flexible connection lines, the one or more sensors contained in the measuring element are constructed on a single, multi-pole electrical bushing, which form an integral unit with the latter. The measuring element constructed on the bushing is housed in a cutout of the measuring-element housing so that it can oscillate and is free from tension. The cutout is closed by the bushing in the manner of a plug.
    Type: Grant
    Filed: February 7, 1997
    Date of Patent: September 8, 1998
    Assignee: Hartmann & Braun GmbH & Co. KG
    Inventor: Jurgen Biskup
  • Patent number: 5765436
    Abstract: A meter body for use in a pressure transmitter in a continuous pressurized transmission system. The meter body is cylindrical in form with a bottom end (including a flexible diaphragm) adapted to engage a flexible gasket to form a so-called "sanitary-seal" connection. The top end is configured to be connected to a sensor capsule.
    Type: Grant
    Filed: May 23, 1997
    Date of Patent: June 16, 1998
    Inventors: Douglas W. Wilda, James V. Davidson
  • Patent number: 5763784
    Abstract: A differential pressure transducer unit with an overload protection system to measure slight differential pressure in liquids and gases under high static compression loading, which unit can be connected by flanges to the differential-pressure lines. To avoid disturbing influences on the measuring element caused by radial tensions of the means of the overload protection system dependent on the absolute pressure, the measuring element is fasten in a cutout of the measuring-element housing so that it can oscillate and is free from tension. Each insulation plate is fitted with an eccentrically located measuring duct through which pressure-measuring agent flows, and which is connected at least indirectly to the measuring element.
    Type: Grant
    Filed: February 7, 1997
    Date of Patent: June 9, 1998
    Assignee: Hartmann & Braun GmbH & Co. KG
    Inventor: Jurgen Biskup
  • Patent number: 5760310
    Abstract: A pressure transmitter has a pressure sensor coupled to an isolator diaphragm by a fill fluid such as oil. According to the invention, means are provided for measuring the position of the isolator diaphragm and comparing the measured position with an expected position to give an indication of fill fluid leakage. Non-contact arrangements such as capacitive and ultrasonic techniques are disclosed for measuring isolator diaphragm position, as well as contacting arrangements such as switches. The fill fluid loss arrangement can be incorporated into a two-wire transmitter, which transmitter can be made to send a warning signal to a control unit when fill fluid loss is detected.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: June 2, 1998
    Assignee: Rosemount Inc.
    Inventors: Stanley E. Rud, Jr., William E. Petrich, Bennett L. Louwagie, Terrance F. Krouth
  • Patent number: 5752674
    Abstract: A system is provided for reducing ice mass on an aircraft engine. A compressor inlet temperature and pressure sensor measures total temperature and total pressure at the inlet to the engine compressor. An ice shield is provided, wherein a plurality of wedge portions has multiple protrusions for promoting ice formation in multiple locations. The ice shield is separable from the sensor with which it interfaces. The ice shield comprises straight angle wedge shapes and curved surfaces to separate and minimize ice accretion in desired locations. The mass of each resultant ice formation is reduced to a size that the compressor inlet blades can withstand without deformation.
    Type: Grant
    Filed: August 21, 1996
    Date of Patent: May 19, 1998
    Assignee: General Electric Company
    Inventors: John S. Mears, Ronald A. Bulow, David L. Joyce, Kevin H. Kast
  • Patent number: 5753819
    Abstract: A pressure sensor including a housing having an interior surface forming a cavity, and a fill passageway communicating with the cavity. The fill passageway has opposite ends defining an axis extending between the ends, and one of ends defines a fill port spaced from the cavity. A pressure transducer is mounted on said interior surface. The pressure sensor also includes a sealing member moveable across the fill port in a direction transverse to the axis between a first position allowing fluid flow through the fill passageway and a second position closing the fill passageway such that the fluid is sheared off at the fill port to seal said cavity. Preferably, the fluid pressure within the cavity before sealing is substantially equal to the fluid pressure within the cavity after sealing.
    Type: Grant
    Filed: September 18, 1996
    Date of Patent: May 19, 1998
    Assignee: SSI Technologies, Inc.
    Inventors: Paul B. Rozgo, Robert C. Cooney, Michael F. Mattes, Jeffrey A. Kuberka, William J. Day, James D. Seefeldt
  • Patent number: 5753820
    Abstract: A sensing unit includes a re-usable portion which is isolated from system fluids and a disposable portion. The disposable portion includes an enclosure that defines an internal cavity with one wall of the enclosure being constituted by a flexible diaphragm that is exposed to operating pressure of the system. The re-usable portion has mounted therein a sensing array at a position adjacent to a non-system pressure side surface of the diaphragm. The sensing array includes a plurality of sensing elements which are arranged as radial inner and outer sets with each set being adapted to preferentially sense a deflection of a central portion of the diaphragm. An output signal representative of the fluid pressure in the fluid system is established based on a ratio of deflection signals from the sets of sensing elements. Preferably, the sensing elements constitute capacitive plates that have equally exposed surface areas.
    Type: Grant
    Filed: October 25, 1996
    Date of Patent: May 19, 1998
    Assignee: Arthur D. Little, Inc.
    Inventors: Michael A. Reed, Paul Franzosa
  • 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: 5750899
    Abstract: To provide a flush-mounted and corrosion-resistant pressure sensor for measuring the pressure of a medium which, on the one hand, is very rugged and, on the other hand, has a casing (2) mechanically isolated from the sensing element (1) as perfectly as possible, and whose measured values exhibit little temperature dependence and little hysteresis, the casing (2) has an internal space (21) and is preferably pot-shaped for receiving the sensing element (1). An annular, particularly annular-disk-shaped, flexible connecting element (3), disposed between the casing (2) and the sensing element (1), and the sensing element close the interior space (21) toward the medium to be measured, and a liquid (4) fills the enclosed interior space (21).
    Type: Grant
    Filed: September 15, 1997
    Date of Patent: May 12, 1998
    Assignee: ENVEC Mess- und Regeltechnik GmbH + Co.
    Inventors: Frank Hegner, Elke Maria Schmidt, Ulfert Drewes, Rainer Martin
  • 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: 5741975
    Abstract: A pressure sensor (10) includes a base (12) supporting a lead frame (28) having a pressure sensing element (14) electrically coupled to the lead frame (28). The molded base (12) interlocks with first and second diaphragm mounting frames (18, 20) and together with first and second diaphragms (22, 24) forms first and second chambers (36, 40). An incompressible fluid resides in the first and second chambers (36, 40) and transfers the pressure of a sensed media impinging on either of the first or second diaphragms (22, 24) to the pressure sensing element (14). The incompressible fluid filling the first and second chambers (36, 40), together with the flexible and impermeable membrane material of the first and second diaphragms (22, 24) effectively isolates the pressure sensing element (14) from the sensed media.
    Type: Grant
    Filed: July 31, 1996
    Date of Patent: April 21, 1998
    Assignee: Motorola, Inc.
    Inventors: John Howard Vaughn, II, Donald Ora Myers, Jeffrey Alan Bykowski
  • Patent number: 5741974
    Abstract: A pressure sensor comprising a hollow main body (1) defining a bore (3) extending therethrough. A pressure sensing assembly (12) is disposed within the bore (3) to divide it into a detection cavity (3a) for transmitting therethrough the pressure to be detected at a pressure receiving end (3c) thereof and an output cavity (3b) through which an output signal from the pressure sensing assembly (12) is to be supplied. A flexible metal diaphragm (40) is attached to the main body (1) at the pressure receiving end (3c) to seal the detection cavity (3a) in which a pressure transmitting medium (11) is filled. The flexible metal diaphragm ( 40) has a resonance frequency above an oscillation frequency range of the pressure to be detected. Preferably, the effective diameter of the diaphragm (40) may be from 7.5 mm to 8.5 mm and the thickness dimension thereof may be from 35 .mu.m to 45 .mu.m.
    Type: Grant
    Filed: February 2, 1993
    Date of Patent: April 21, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Fumito Uemura
  • Patent number: 5731522
    Abstract: A process control transmitter includes a transmitter housing and transmitter circuitry adapted for providing a transmitter output related to a sensed pressure. A sensor coupling in the housing defines a pressure sensor cavity which is filled with isolation fluid. An isolation diaphragm separates the sensor cavity from a process fluid and is adapted to transmit pressure therebetween. The pressure sensor is mounted in the sensor cavity and provides an output related to pressure to the transmitter circuitry. A thermal compensation member is coupled to the sensor cavity and has a thermal expansion coefficient which is different than a thermal expansion coefficient for the sensor coupling. The compensation member is adapted to compensate for pressure changes due to thermal expansion of the components or isolation fluid.
    Type: Grant
    Filed: March 14, 1997
    Date of Patent: March 24, 1998
    Assignee: Rosemount Inc.
    Inventor: Fred C. Sittler
  • Patent number: 5722399
    Abstract: A liquid treatment apparatus includes a sensor which is sensitive to a variation in gas pressure and which generates signals indicative of sensed pressures. The apparatus also included a casing divided into a first compartment and a second compartment by a flexible membrane, the first compartment having at least one orifice for the introduction of the liquid, and the second compartment being connectable in a leaktight manner to the pressure sensor. A pump is provided to vary a quantity of gas in the second compartment, and a controller is provided to regulate the pump as a function of variations in pressure generated in the second compartment. The controller is configured to receive signals from the sensor and to cause, through the pump, at least two successive pressure variations, having opposite directions, in the second compartment so as to adjust said position of the membrane between a wall of the casing bounding the first compartment and a wall of the casing bounding the second compartment.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: March 3, 1998
    Assignee: Hospal Industrie
    Inventors: Jacques Chevallet, Alain Frugier, Eric Louvet
  • Patent number: 5721382
    Abstract: An apparatus for visually indicating fluid flow through a fluid system or apparatus such as a medical infusion device. The apparatus comprises a pair of thin, indicia bearing films disposed in an overlaying relationship. These films are shifted relative to each other by movement of mechanical actuators which are deflected solely by the pressure of the fluid within the fluid conduits of the system of the apparatus. The two films are stacked in closed proximity and are preferably constructed from a substantially transparent flexible material such as mylar. One surface of the inferior film is printed with a plurality of integrated symbols depicting various fluid flow conditions. The superior film functions as a mask over the inferior film and is printed with a pattern of diagonally extending, alternating clear and opaque stripes. The print ratio of the superior film permits viewing at any one time of only one of the symbols printed on the inferior film.
    Type: Grant
    Filed: September 24, 1996
    Date of Patent: February 24, 1998
    Inventors: Marshall S. Kriesel, James M. Garrison, Steven Arnold, Farhad Kazemzadeh
  • Patent number: 5693887
    Abstract: A non-contaminating pressure sensor module having an isolation member is disclosed. The isolation member isolates a pressure sensor within the transducer module from exposure to fluids flowing through a conduit in the module. The transducer module may be positioned in-line within a fluid flow circuit carrying corrosive materials, wherein the pressure transducer module produces a control signal proportional to either a gauge pressure or an absolute pressure of the fluid flow circuit. The pressure transducer module of the present invention also avoids the introduction of particulate, unwanted ions, or vapors into the flow circuit.
    Type: Grant
    Filed: October 3, 1995
    Date of Patent: December 2, 1997
    Assignee: NT International, Inc.
    Inventors: Diane L. Englund, Gerald R. Cucci
  • Patent number: 5684253
    Abstract: The present invention relates generally to a pressure sensor and, more specifically, to a pressure equalization structure that balances the forces on the pressure sensitive component in order to reduce the stress that could otherwise be imposed on its piezoresistors. The pressure sensor provides a housing in which a cavity is formed. Within the cavity, a pressure sensitive component is disposed between a first seal and a second seal in order to expose a first surface of the pressure sensitive component to a first conduit and a second surface of the pressure sensitive component to a second conduit. The pressure surrounding the pressure sensitive structure is generally equalized to one of the first and second conduits by providing a bypass conduit connected therebetween.
    Type: Grant
    Filed: January 8, 1997
    Date of Patent: November 4, 1997
    Assignee: Honeywell Inc.
    Inventors: Ulrich Bonne, D. Joseph Maurer
  • Patent number: 5672832
    Abstract: A non-contaminating flow meter having an isolation member is disclosed. The flow meter includes two pressure sensor transducers, located on opposite sides of a restriction in a conduit. Each of pressure transducers is isolated by an isolation member from exposure to fluids flowing through the conduit. The flow meter may be positioned in-line within a fluid flow circuit carrying corrosive materials, wherein the square root of the difference in pressure between the two pressure sensors is calculated to thereby determine the rate of flow within the fluid flow conduit. The flow meter compensates for changes in temperature within the fluid flow circuit and further activates an alarm if the pressure or flow rate within the fluid flow conduit exceeds or falls below a threshold level. The flow meter of the present invention also avoids the introduction of particulate, unwanted ions, or vapors into the flow circuit.
    Type: Grant
    Filed: February 15, 1996
    Date of Patent: September 30, 1997
    Assignee: NT International, Inc.
    Inventors: Gerald R. Cucci, Diane L. Englund
  • Patent number: 5661244
    Abstract: In a pressure sensor, a metallic pressure introducing pipe is fit into the pressure receiving inlet formed in a metallic housing and fixed there by welding. The housing has a flange portion in its upper portion, and the flange portion is fixed to the outer wall of a tank which is an object to be measured so that the pressure sensor body is located inside the tank. A porous filter made of fluoroplastics is arranged adjacently to the atmospheric pressure introducing inlet. An adhesive tape which is removable is attached to the atmospheric pressure introducing inlet. The pressure sensor can realize stabilized maintenance and highly reliable airtightness for a sensor element, less limitation to sensor layout design in a small space and also can surely introduce air with no drop of water and dust into the sensor.
    Type: Grant
    Filed: March 22, 1995
    Date of Patent: August 26, 1997
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Etsuo Nishimura, Tateki Mitani
  • Patent number: 5652391
    Abstract: A double-diaphragm gauge protector constructed according to principles of this invention comprises a diaphragm housing formed from a upper housing body, a lower housing body, and a central housing body interconnected between the upper and lower housing bodies. A first diaphragm is disposed within the upper housing body forming an upper chamber therebetween and a liquid pressure-transfer medium is disposed within the upper chamber. The first diaphragm includes a transfer pad that projects outwardly away from a frontside or downwardly facing bottom surface of the first diaphragm toward the lower housing body. A second diaphragm is disposed within the lower housing body forming a lower chamber therebetween. The second diaphragm also includes a transfer pad that projects outwardly away from a frontside or upwardly facing top surface of the second diaphragm toward the first diaphragm. The transfer pads of the first and second diaphragms are positioned one on top of the other.
    Type: Grant
    Filed: May 12, 1995
    Date of Patent: July 29, 1997
    Assignee: Furon Company
    Inventors: Kenji A. Kingsford, Anthony K. Chan
  • Patent number: 5648614
    Abstract: A seal comprising two rings is disclosed. A sensor or signal generator is immovably affixed to the polymeric member of one of the rings. In one embodiment, the other of the rings includes a corresponding sensor or signal generator, depending on which of these types of elements is affixed to the first ring, that is immovably affixed to the second ring.
    Type: Grant
    Filed: August 17, 1995
    Date of Patent: July 15, 1997
    Assignee: Firma Carl Freudenberg
    Inventors: Rainer Martsfeld, Rolf Vogt, Thomas Kuhlmann, Hanno Wentzler
  • Patent number: 5623102
    Abstract: A pressure difference sensor having a semiconductor measuring diaphragm clamped between two bearing parts of insulating material thereby forming two inner chambers is described. Each of the bearing parts holds a flat electrode on its inside. An internal, pressurized, equalization chamber is provided in the clamping region of the pressure difference sensor and extends into both bearing parts around the inner chambers. The equalization chamber compensates for static pressure influences on the accuracy of the measurement of the sensor. A method for producing the sensor is also described.
    Type: Grant
    Filed: December 13, 1994
    Date of Patent: April 22, 1997
    Assignee: Siemens Aktiengesellschaft
    Inventors: Frank Arndt, Detlef Houdeau, Moritz von Rauch, Helmut Schlaak
  • Patent number: 5621175
    Abstract: A differential pressure transmitter for detecting a difference between a pressure of a first detection fluid in a first pressure-receiving chamber and a pressure of a second detection fluid in a second pressure-receiving chamber, including a first diaphragm for sealing the first detection fluid, a second diaphragm for sealing the second detection fluid which is installed almost in parallel to the first diaphragm, a first isolation chamber communicated to the first pressure-receiving chamber, a second isolation chamber communicated to the second pressure-receiving chamber, a third diaphragm installed between the first and the second chambers and in a direction different from those of the first and second diaphragms, and a differential pressure detection sensor installed on and connected to at least one of the first and the second isolation chambers.
    Type: Grant
    Filed: February 14, 1996
    Date of Patent: April 15, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Akira Nagasu, Yoshimi Yamamoto, Tomoyuki Tobita
  • Patent number: 5614659
    Abstract: A device for measuring soil pore-air pressure in a high shock environment characterized by a shock resistant housing containing a plurality of pressure sensing ports with sintered metal filters mounted therein which filter fine soil particles, withstand high pressure shock, and permit high air flow. When the device is installed in the ground and an explosive is detonated nearby, soil particles are filtered from the air blast by the sintered metal filters, thereby enabling the device to provide accurate pore-air pressure measurements.
    Type: Grant
    Filed: May 16, 1995
    Date of Patent: March 25, 1997
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Denis D. Rickman
  • Patent number: 5596149
    Abstract: A pressure measurement tap for use in a pressurized fluidized bed for preventing a flow of particulate matter into the measurement tap opening. The pressure measurement tap has an inner pipe for providing purge air through the pressure measurement tap which carries the purge air past a pressure gauge conduit and provides for greater accuracy in measurements. A second embodiment has a constant source of purge air provided to the inner pipe.
    Type: Grant
    Filed: October 23, 1995
    Date of Patent: January 21, 1997
    Assignee: The Babcock & Wilcox Company
    Inventor: Douglas J. DeVault
  • Patent number: 5589638
    Abstract: In a pressure sensor with a housing containing a measuring device which is separated from the housing by a radial gap and comprises a pressure transmitting element, a measuring element, and, if required, a tubular spring for axially preloading the measuring element, and with a sealing membrane tightly and flexibly connecting housing and pressure transmitting element on the side of the medium, the proposal is put forward that at least one heat conducting element be provided between the pressure transmitting element and the housing, which element should be made from material of good thermal conductivity and have a large cross-section for heat conduction, such that most of the heat arising in the region of the pressure transmitting element is carried off to the housing via the heat conducting element, the latter acting as bending or rolling element in the instance of axial shifts between the pressure transmitting element and the housing, and being flexible in axial direction to minimize the transmission of force
    Type: Grant
    Filed: May 30, 1996
    Date of Patent: December 31, 1996
    Assignee: AVL Gesellschaft Fur Verbrennungskraftmaschinen und Messtechnik m.b.H. Prof.Dr.Dr.h.c. Hans List
    Inventors: Josef Glaser, Pierre Fornet
  • Patent number: 5583294
    Abstract: A pressure transmitter apparatus having a Unitary body portion, separate diaphragms and flange elements and disposed within the body, a first and second normally vertical pressure passage. The first and second pressure passageways communicate respectively between first and second pressure openings extending-normally horizontally through the body portion, and a transducer mounting element. The mounting element, coupled to the body portion and located above the pressure passageways, mounts a transducer that generates a differential pressure signal. One or a pair of diaphragm elements are configured to form first and second process diaphragms, closing first and second pressure openings. The flange element overlies the diaphragm element and is removably and replaceably secured to the body portion.
    Type: Grant
    Filed: August 22, 1994
    Date of Patent: December 10, 1996
    Assignee: The Foxboro Company
    Inventor: Edwin L. Karas
  • Patent number: 5578760
    Abstract: A seal diaphragm structure for a pressure measuring device includes a seal diaphragm, an insulating film, and an p-type semiconductor film. The seal diaphragm has a first surface opposing a target fluid and a second surface contacting a pressure transfer sealed liquid sealed in the pressure measuring device. The insulating film is formed on the first surface of the seal diaphragm. The p-type semiconductor film is formed on the insulating film.
    Type: Grant
    Filed: March 6, 1995
    Date of Patent: November 26, 1996
    Assignee: Yamatake-Honeywell Co., Ltd.
    Inventor: Motoo Suzuki
  • Patent number: 5565629
    Abstract: The present invention aims to provide a semiconductor type pressure sensor capable of preventing an occurrence of a thermal output value, thereby improving a linearity of the output with respect to a change in the temperature. The sensor includes housing 8 provided with a pressure detecting chamber 3, a pressure receiving diaphragm 2 arranged to be adjacent the liquid confined in the pressure detecting chamber 3, and a pressure detecting element 4 arranged in the pressure detecting chamber 3 so as to receive the pressure of the liquid. The diaphragm 2 includes at a location adjacent its fixed end a corrugation 2c, which is made of a pair of convex and concave portions 2a and 2b, and a flat portion 2d. A ratio of the distance between the convex and concave portions 2a and 2b, and the radius R of the diaphragm 2, and a ratio of the flat portion 2d and the radius R of the diaphragm 2 are set to respective desired ranges.
    Type: Grant
    Filed: August 10, 1994
    Date of Patent: October 15, 1996
    Assignee: Nippondenso Co., Ltd.
    Inventor: Yasuhiro Yamashita
  • Patent number: 5563347
    Abstract: A pumping segment for incorporation into a fluid delivery system, the segment having a dome-shaped pressure vessel with an optimal shape for interfacing with a pressure sensing element, and which is capable of uniformly distributing pressure across its interfacing structure and being optimally pre-loaded against the pressure sensing element. The pumping segment including a lateral restraint to inhibit rupture of the unloaded pressure vessel when experiencing high internal pressures.
    Type: Grant
    Filed: September 12, 1994
    Date of Patent: October 8, 1996
    Inventors: Stephen A. Martin, Robert D. Butterfield, Charles E. Clemens
  • Patent number: 5551300
    Abstract: A pressure monitoring apparatus for use in monitoring a physiological fluid pressure in successive patients. Three embodiments of the pressure monitoring apparatus (10, 100, 200) are disclosed, each of which include a disposable portion ( 12, 12', 12") and a reusable portion ( 14, 14', 14"). Fluid flows through the disposable portion and into a cavity (48) that is covered with an elastomeric membrane (46, 46'). When the disposable portion is engaged with the reusable portion, the elastomeric membrane is in contact with a corresponding elastomeric membrane (50, 50'), which covers a pressure sensing cavity (52). A pressure transducer (56) is mounted in the pressure sensing cavity, and the pressure sensing cavity is filled with a fluid and is in fluid communication with a reservoir(38) when not engaged with the disposable portion.
    Type: Grant
    Filed: December 18, 1995
    Date of Patent: September 3, 1996
    Assignee: Abbott Laboratories
    Inventors: Gerald G. Vurek, Harlow B. Christianson
  • Patent number: 5551303
    Abstract: To ensure insensitivity to electromagnetic interference and to charge influences from the oil fill and achieve good long-term stability, this pressure-measuring arrangement comprises: a pressure sensor having a base and an associated diaphragm with strain gages deposited thereon; a header of insulating material with leads and with an oil filler neck, said header of insulating material having the base mounted thereon, and said leads making electrical contacts to the strain gages; a metal body having a first central recess in a first cross-sectional surface, a second central recess in a second cross-sectional surface facing away from the first cross-sectional surface, and a hole connecting the first recess with the second recess, said first cross-sectional surface being tightly joined at its edge to the header of insulating material, and said first recess accommodating the substrate and diaphragm without touching them; an electrically conductive foil having an opening, said foil being disposed in the first rece
    Type: Grant
    Filed: December 5, 1994
    Date of Patent: September 3, 1996
    Assignee: ENVEC Mess-und Regeltechnik GmbH + Co.
    Inventors: Arno Donner, Norbert Gill, Jurgen Lange, Volker Schrobel, Rolf Schade
  • Patent number: 5552015
    Abstract: The invention relates to a process for making an oblique-sided recess in a substrate in which areas of the surface of the substrate corresponding to the recess to be made are covered with an etching mask which is not attacked by an isotropic etching liquid, whereupon an isotropic etching is effected. In order to be able to make oblique sides of very slight slope with such a process, a layer (4) which is removable by the isotropic etching liquid is applied to the surface areas (3) of the substrate (2) before the application of the etching mask (5).
    Type: Grant
    Filed: September 28, 1994
    Date of Patent: September 3, 1996
    Assignee: Siemens Aktiengesellschaft
    Inventors: Frank Arndt, Helmut Schlaak
  • Patent number: 5551299
    Abstract: A pressure measuring apparatus comprising a seal diaphragm that separates a fluid to be measured from a pressure transmitting medium that transmits a pressure variation of the fluid to be measured to a pressure detecting section. In such an apparatus, a non-electrically conductive film is coated on a surface of the seal diaphragm which is on the side of the fluid to be measured. As a result of the above construction, the pressure can be measured accurately over a long period of time while preventing hydrogen from passing through the seal diaphragm surely and protecting the seal diaphragm.
    Type: Grant
    Filed: August 25, 1994
    Date of Patent: September 3, 1996
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Mitsuru Tamai, Hironobu Yao, Masao Saitoh