Patents by Inventor Ulfert Drewes

Ulfert Drewes has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20050103109
    Abstract: A pressure sensor for measuring a pressure includes a pressure chamber; and a deformation body, which can be exposed to a medium under pressure, and which, additionally, at least partially bounds the pressure chamber and seals such pressure-tightly from the medium; wherein the walls of the sensor chamber have a hydrophobic coating, which was applied by gas and/or vapor phase deposition. The hydrophobic coating preferably includes a silane. Especially suited are silanes having one or more hydrophobic groups R and one or more anchoring groups X. Especially preferred are: R—Si—X3, R1R2—Si—X2, R1R2R3—Si—X. The hydrophobic group R is preferably an alkyl, perfluoroalkyl, phenyl or perflurorophenyl group. The anchoring group X is preferably an —OH (silanol), —X (halide, e.g. —Cl), —OR (ester, e.g. —OCH3), —NH2 (amine), or —SH (Mercaptosilane). Additionally, aliphatic or cyclic silazanes —Si—NH—Si—, e.g. hexamethyldisilazane, can be used. Likewise suitable are compounds of the type Ry—Me—Xz, with Me=e.g. Zr, Ti.
    Type: Application
    Filed: December 18, 2002
    Publication date: May 19, 2005
    Inventors: Frank Hegner, Ulfert Drewes, Andreas Rossberg, Elke Schmidt
  • Patent number: 6848318
    Abstract: A pressure sensor that is particularly suitable inter alia for the food industry and the measuring accuracy of which is stable over a long time, having a diaphragm seal (3, 45) with a separating diaphragm (7, 53) on which a pressure (P) to be measured acts and having a ceramic measuring cell (9, 57) which is connected to the diaphragm seal (3, 45) exclusively by inorganic materials, is provided, in which sensor the separating diaphragm (7, 53) and all further sensor components coming into contact during measurement with a medium of which the pressure (P) is to be measured are metallic.
    Type: Grant
    Filed: January 23, 2004
    Date of Patent: February 1, 2005
    Assignee: Endress + Hauser GmbH + Co.
    Inventors: Peter Gerst, Karlheinz Banholzer, Karl Flögel, Thomas Uehlin, Frank Hegner, Elke Schmidt, Ulfert Drewes, Rainer Martin
  • Publication number: 20040149042
    Abstract: A pressure sensor that is particularly suitable inter alia for the food industry and the measuring accuracy of which is stable over a long time, having a diaphragm seal (3, 45) with a separating diaphragm (7, 53) on which a pressure (P) to be measured acts and having a ceramic measuring cell (9, 57) which is connected to the diaphragm seal (3, 45) exclusively by inorganic materials, is provided, in which sensor the separating diaphragm (7, 53) and all further sensor components coming into contact during measurement with a medium of which the pressure (P) is to be measured are metallic.
    Type: Application
    Filed: January 23, 2004
    Publication date: August 5, 2004
    Applicant: ENDRESS + HAUSER GMBH + CO.
    Inventors: Peter Gerst, Karlheinz Banholzer, Karl Flogel, Thomas Uehlin, Frank Hegner, Elke Schmidt, Ulfert Drewes, Rainer Martin
  • Publication number: 20040105215
    Abstract: In a differential pressure sensor, the measurement value is corrected with the help of the nominal pressure NP. In this way, influences on the measurement value because of deformations of the body of the differential pressure sensor and change in the material stiffness of the membrane are decreased.
    Type: Application
    Filed: October 6, 2003
    Publication date: June 3, 2004
    Inventors: Frank Hegner, Ulfert Drewes, Andreas Rossberg, Elke Schmidt
  • Patent number: 6715356
    Abstract: A pressure sensor that is particularly suitable for the food industry and the measuring accuracy of which is stable over a long time, having a diaphragm seal with a separating diaphragm on which a pressure to be measured acts and having a ceramic measuring cell which is connected to the diaphragm seal exclusively by inorganic materials, is provided, in which sensor the separating diaphragm and all further sensor components coming into contact during measurement with a medium of which the pressure is to be measured are metallic.
    Type: Grant
    Filed: December 13, 2000
    Date of Patent: April 6, 2004
    Inventors: Peter Gerst, Karlheinz Banholzer, Karl Flögel, Thomas Uehlin, Frank Hegner, Elke Schmidt, Ulfert Drewes, Rainer Martin
  • Patent number: 6675654
    Abstract: A chamber in the interior of a housing communicates with the environment of the housing by means of a gas esxchange path, wherein a filter element with a hydrophobic and/or hydrophobicized, nanoporous material is placed in the gas exchange path. The chamber serves, e.g. to accomodate electronic circuitry, or it is chamed as a reference pressure chamber of a relative pressure sensor. The relative pressure sensor according to the present invention for capturing a measured pressure with respect to a reference pressure comprises a reference pressure path 23 which extends between a surface which can be exposed to the reference pressure and an opening in a reference pressure chamber 22, a filter element 30 which is arranged in the reference pressure path comprising a hydrophobic or hydrophobicized, nanoporous material. The filter element allows pressure compensation on account of its permeability to N2 and O2, while water molecules are selectively blocked.
    Type: Grant
    Filed: May 6, 2002
    Date of Patent: January 13, 2004
    Assignee: Endress + Hauser GmbH + Co. KG
    Inventors: Frank Hegner, Andreas Rossberg, Elke Schmidt, Ulfert Drewes, Michael Kirst, Bernhard Walter
  • Patent number: 6595064
    Abstract: A diaphragm 30 and basic body 20 of a pressure sensor 10 are interconnected via a joint F. A groove 26 is provided in the basic body 20 in order to reduce the stress concentration in the region of the joint F.
    Type: Grant
    Filed: May 24, 2001
    Date of Patent: July 22, 2003
    Assignee: Endress + Hauser GmbH + Co.
    Inventors: Ulfert Drewes, Andreas Rossberg, Frank Hegner, Elke Maria Schmidt, Jürgen Breme, Thomas Velten
  • Publication number: 20030005772
    Abstract: A chamber in the interior of a housing communicates with the environment of the housing by means of a gas esxchange path, wherein a filter element with a hydrophobic and/or hydrophobicized, nanoporous material is placed in the gas exchange path. The chamber serves, e.g. to accomodate electronic circuitry, or it is chamed as a reference pressure chamber of a relative pressure sensor. The relative pressure sensor according to the present invention for capturing a measured pressure with respect to a reference pressure comprises a reference pressure path 23 which extends between a surface which can be exposed to the reference pressure and an opening in a reference pressure chamber 22, a filter element 30 which is arranged in the reference pressure path comprising a hydrophobic or hydrophobicized, nanoporous material. The filter element allows pressure compensation on account of its permeability to N2 and O2, while water molecules are selectively blocked.
    Type: Application
    Filed: May 6, 2002
    Publication date: January 9, 2003
    Inventors: Frank Hegner, Andreas Rossberg, Elke Schmidt, Ulfert Drewes, Michael Kirst, Bernhard Walter
  • Patent number: 6422085
    Abstract: In this flush-diaphragm relative pressure sensor (1), the reference air reaches its current dew point before getting into the interior of the housing. The sensor has a capacitive, resistive, or piezoelectric sensing element (2) with a diaphragm (21) an external surface of which comes into direct contact with a medium under pressure. A housing (7) has an interior space (71) and a front portion (72) open across the interior space in the vicinity of which the diaphragm closes the interior space such that the front portion projects beyond the diaphragm. Further, the housing has a bore (721) extending through the front portion from an outer side thereof to the interior space for guiding the reference air. The bore is closed from the outer side with an open-pore, highly heat-conducting and hydrophobic filter (8), so that the filter and the diaphragm are at the same or nearly the same temperature. The filter can be made of a sintered metal, e.g. high-grade steel or bronze, or of a metallic sponge, e.g.
    Type: Grant
    Filed: July 16, 1999
    Date of Patent: July 23, 2002
    Assignee: Endress + Hauser GmbH + Co.
    Inventors: Frank Hegner, Andreas Rossberg, Ulfert Drewes, Elke Schmidt
  • Patent number: 6374680
    Abstract: The electrodes of these pressure or differential pressure sensors are formed using a technique other than silk-screen printing or sputtering: The pressure sensor (10) has a substrate (1) and a first major surface (11), a second major surface (12) and a circumferential surface (13. A plate-shaped electrode (14) of electrically conductive material is secured in a recess (15) in the major surface (11) in a high-pressure-resistant and high-vacuum-tight manner by a joining material (16). A through connection (17) is provided from the electrode (14) through the substrate (1) to the major surface (12) or the circumferential surface (13). A diaphragm (2) of ceramic, glass, or single-crystal material is attached to the substrate (1) outside the recess (15) along a joint (18) by a joining material (26), and forms itself a further electrode or is covered, on a surface facing the electrode (14), with a further electrode (24) which is contacted through the joint (18).
    Type: Grant
    Filed: February 21, 2000
    Date of Patent: April 23, 2002
    Assignee: Endress + Hauser GmbH + Co.
    Inventors: Ulfert Drewes, Andreas Rossberg, Elke Schmidt, Frank Hegner, Thomas Velten
  • Publication number: 20020026836
    Abstract: A pressure measurement cell is provided whose measurement accuracy is stable over a long time, having a first and a second base body (1, 3), and arranged between the first and the second base body (1, 3), at a distance from them, a measurement membrane (5) which has a low-pressure side on which it is connected to the first base body (1), at a first outer edge, to form a first chamber (7), and which has a high-pressure side on which it is connected to the second base body (3), at a second outer edge, to form a second chamber (9), the first edge being wider than the second edge.
    Type: Application
    Filed: May 25, 2001
    Publication date: March 7, 2002
    Applicant: Endress + Hauser GmbH+ Co.
    Inventors: Frank Hegner, Ulfert Drewes
  • Publication number: 20020014124
    Abstract: A diaphragm 30 and basic body 20 of a pressure sensor 10 are interconnected via a joint F. A groove 26 is provided in the basic body 20 in order to reduce the stress concentration in the region of the joint F FIG. 2).
    Type: Application
    Filed: May 24, 2001
    Publication date: February 7, 2002
    Applicant: Endress + Hauser GmbH + Co.
    Inventors: Ulfert Drewes, Andreas Rossberg, Frank Hegner, Elke Maria Schmidt, Jurgen Breme, Thomas Velten
  • Publication number: 20010015105
    Abstract: A pressure sensor that is particularly suitable inter alia for the food industry and the measuring accuracy of which is stable over a long time, having a diaphragm seal (3, 45) with a separating diaphragm (7, 53) on which a pressure (P) to be measured acts and having a ceramic measuring cell (9, 57) which is connected to the diaphragm seal (3, 45) exclusively by inorganic materials, is provided, in which sensor the separating diaphragm (7, 53) and all further sensor components coming into contact during measurement with a medium of which the pressure (P) is to be measured are metallic.
    Type: Application
    Filed: December 13, 2000
    Publication date: August 23, 2001
    Applicant: Endress + Hauser GmbH + Co.
    Inventors: Peter Gerst, Karlheinz Banholzer, Karl Flogel, Thomas Uehlin, Frank Hegner, Elke Schmidt, Ulfert Drewes, Rainer Martin
  • Patent number: 6267009
    Abstract: These capacitive pressure sensor cells have joints between substrates and diaphragms being both pressure and/or tension-proof and high-vacuum-tight and long-term-stable. The sensor cell comprises a ceramic substrate (1) having a cylindrical surface (11), a major surfaces (12, 13). The major surface (12) includes a concave central area (121) merging, in the direction of and up to said cylindrical surface (11), into a convex surface (124) having a vertex line (125) and forming a planar ring surface (126) in its area. An electrode (122) is located in the concave area (121). An electrical connection (123) extends from electrode (122) through the substrate (1) to surface (13). A ceramic diaphragm (5) has a planar inner surface (51) on which an electrode (52) is located and which rests on the ring surface (126) of the substrate (1).
    Type: Grant
    Filed: February 16, 2000
    Date of Patent: July 31, 2001
    Assignee: Endress + Hauser GmbH + Co.
    Inventors: Ulfert Drewes, Elke Schmidt, Andreas Rossberg, Frank Hegner, Thomas Velten
  • 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: 5400489
    Abstract: To avoid any deterioration of the surface properties of objects of ceramic, glass, or a single-crystal insulating material which are subjected to a vacuum temperature process, a thin layer of a spin-on glass solution with a silicon-dioxide equivalent of not more than 10% is applied to the objects by spinning or spraying prior to the vacuum temperature process. This is particularly important to avoid the strong moisture dependence of capacitive or resistive pressure sensors having a substrate and a diaphragm to be joined together, forming a chamber sealed at least at the edge.
    Type: Grant
    Filed: October 30, 1992
    Date of Patent: March 28, 1995
    Inventors: Frank Hegner, Ulfert Drewes