Patents by Inventor Hagen Mittelstrass

Hagen Mittelstrass 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).

  • Patent number: 8590607
    Abstract: A heat exchanger includes a tube with a heat-exchange passage and an end piece. The heat-exchange passage directs the flow of a first medium and includes a first flow section and a second flow section arranged in parallel. The end piece has a tube plate that includes a base plate, a diverter plate, and a cover plate. An end of the tube connects to the base plate. The diverter plate has a cutout that forms a diverter passage. The cover plate lies adjacent to the diverter plate and covers the diverter passage in a fluid-tight manner. A second medium flows exterior to the heat-exchange passage.
    Type: Grant
    Filed: January 8, 2009
    Date of Patent: November 26, 2013
    Assignee: Behr GmbH & Co. KG
    Inventors: Walter Demuth, Martin Kotsch, Michael Kranich, Hans Joachim Krauss, Hagen Mittelstrass, Karl-Heinz Staffa, Christoph Walter
  • Patent number: 7650935
    Abstract: The invention relates to a heat exchanger comprising tubes (2, 3) that can be flown through along a number of hydraulically parallel flow paths (2c, 2d) that are comprised of sections.
    Type: Grant
    Filed: December 19, 2002
    Date of Patent: January 26, 2010
    Assignee: BEHR GmbH & Co. KG
    Inventors: Walter Demuth, Martin Kotsch, Michael Kranich, Hans Joachim Krauss, Hagen Mittelstrass, Karl-Heinz Staffa, Christoph Walter
  • Publication number: 20090126920
    Abstract: Disclosed herein is a heat exchanger with tubes (1) and at least one end piece, which has a tube bottom that, in turn, has a bottom plate (8), a baffle plate (12) and a covering plate (16).
    Type: Application
    Filed: January 8, 2009
    Publication date: May 21, 2009
    Inventors: Walter Demuth, Martin Kotsch, Michael Kranich, Hans Joachim Krauss, Hagen Mittelstrass, Karl-Heinz Staffa, Christoph Walter
  • Patent number: 7481266
    Abstract: Disclosed herein is a heat exchanger with tubes (1) and at least one end piece, which has a tube bottom that, in turn, has a bottom plate (8), a baffle plate (12) and a covering plate (16).
    Type: Grant
    Filed: December 19, 2002
    Date of Patent: January 27, 2009
    Assignee: Behr GmbH & Co. KG
    Inventors: Walter Demuth, Martin Kotsch, Michael Kranich, Hans Joachim Krauss, Hagen Mittelstrass, Karl-Heinz Staffa, Christoph Walter
  • Patent number: 7146819
    Abstract: The invention relates to a method of refrigerant level monitoring in a refrigerant circuit of an air-conditioning or heat-pump system having a compressor and a refrigerant which may, depending on the operating point, be operated in the supercritical range. The method includes standstill level monitoring with the compressor switched off and/or in-operation level monitoring with the compressor switched on. In the case of in-operation level monitoring, the refrigerant overheat (dTü) at the evaporator is registered and, in the event of excessive overheat, it is concluded that there is underfilling. At a standstill, the pressure and temperature of the refrigerant are registered, and it is concluded that there is an improper refrigerant filling level if the pressure (pKM) lies below a minimum pressure value (pmin) or the temperature (TKM) lies above a maximum saturation temperature value (TS) with the pressure being outside a predefinable intended pressure range ([pu,po]).
    Type: Grant
    Filed: February 10, 2004
    Date of Patent: December 12, 2006
    Assignee: BEHR GmbH & Co.
    Inventors: Walter Demuth, Rainer Heilig, Volker Kirschner, Martin Kotsch, Hans-Joachim Krauss, Hagen Mittelstrass, Harald Raiser, Michael Sickelmann, Karl-Heinz Staffa, Christoph Walter
  • Patent number: 6993838
    Abstract: The invention relates to a collector tube (1) for a heat transfer unit. The tube comprises one or several slits (3d) on the periphery thereof, whereby said slits are formed by a punch press without an inner die or by high-pressure shaping for inserting a respective flat tube. The invention also relates to a method for producing said collector tube (1). According to the invention, a collector tube (1) is provided with an outer radius (D/2) to tube wall thickness (s) ratio of less than 5. The slits (3d) are introduced preferably parallel to, or at an acute 2 angle to the longitudinal axis of the tube. The collection tube can be produced by bending a flat material and subsequently sealing the longitudinal slits arising from the bending process by soldering or welding. Said collector tube can be used, e.g. for gas coolers and evaporators for CO2 air conditioning systems in motor vehicles.
    Type: Grant
    Filed: February 29, 2000
    Date of Patent: February 7, 2006
    Assignee: Behr GmbH & Co.
    Inventors: Karl-Heinz Staffa, Hans-Joachim Krauss, Hagen Mittelstrass, Christoph Walter, Bernd Dienhart
  • Publication number: 20050103486
    Abstract: The invention relates to a heat exchange comprising tubes (2,3) that can be flown through along a number of hydraulically parallel flow paths (2c, 2d) that are comprised of sections.
    Type: Application
    Filed: December 19, 2002
    Publication date: May 19, 2005
    Inventors: Walter Demuth, Martin Kotsch, Michael Kranich, Hans Krauss, Hagen Mittelstrass, Karl-Heinz Staffa, Christoph Walter
  • Publication number: 20050039901
    Abstract: The invention relates to a heat exchanger comprising tubes (1) and at least one end piece, which has a tube bottom that, in turn, has a bottom plate (8), a baffle plate (12) and a covering plate (16).
    Type: Application
    Filed: December 19, 2002
    Publication date: February 24, 2005
    Inventors: Walter Demuth, Martin Kotsch, Michael Kranich, Hans Krauss, Hagen Mittelstrass, Martin Kotsch, Michael Kranich, Hans Krauss, Hagen Mittelstrass, Karl-Heinz Staffa, Christoph Walter
  • Patent number: 6843312
    Abstract: An air conditioning system has a refrigerant cycle, a coolant cycle, a refrigerant/coolant heat exchanger, coupling these cycles so as to transfer heat, and a valve for operating mode-dependent control of the refrigerant flow, whereby the air conditioning system can be operated not only in air conditioning mode but also in a heat pump or reheat mode. An internal combustion engine exhaust gas/coolant heat exchanger is connected upstream in series to the refrigerant/coolant heat exchanger in the coolant cycle in the heat pump mode; and/or in the reheat operating mode the refrigerant/coolant heat exchanger functions as a condenser/gas cooler, connected upstream in series on the coolant side to the supply air/coolant heat exchanger. In addition or as an alternative, a drying operating mode can be provided for drying the supply air/refrigerant heat exchanger with reversed air conveying direction.
    Type: Grant
    Filed: February 15, 2001
    Date of Patent: January 18, 2005
    Assignee: Behr GmbH & Co.
    Inventors: Roland Burk, Hans-Joachim Krauss, Hagen Mittelstrass, Karl-Heinz Staffa, Christoph Walter
  • Patent number: 6810949
    Abstract: A multiblock heat-transfer system including a first heat-transfer unit and at least a second heat transfer unit mounted onto the first heat-transfer unit. The first heat transfer unit contains a first heat-transfer tubular block with at least a first collecting chamber at the side. The second heat-transfer unit contains a second heat-transfer tubular block with at least a second collecting chamber at the side. The first and second collecting chamber each consist of their own collecting pipe, and both collecting pipes are inserted into each other at their front faces and are connected in a fluid-tight manner. In the pipe connection area, the external diameter of one of the collecting pipes approximately matches the internal diameter of the other collecting pipe, and a transverse partition is provided for separating the two collecting chambers.
    Type: Grant
    Filed: January 7, 2002
    Date of Patent: November 2, 2004
    Assignee: BEHR GmbH & Co.
    Inventors: Karl-Heinz Staffa, Hans-Joachim Krauss, Hagen Mittelstrass, Christoph Walter, Bernd Dienhart, Jochen Schumm
  • Publication number: 20040159114
    Abstract: The invention relates to a method of refrigerant level monitoring in a refrigerant circuit of an air-conditioning or heat-pump system having a compressor and a refrigerant which may, depending on the operating point, be operated in the supercritical range. The method includes standstill level monitoring with the compressor switched off and/or in-operation level monitoring with the compressor switched on. In the case of in-operation level monitoring, the refrigerant overheat (dTü) at the evaporator is registered and, in the event of excessive overheat, it is concluded that there is underfilling. At a standstill, the pressure and temperature of the refrigerant are registered, and it is concluded that there is an improper refrigerant filling level if the pressure (pKM) lies below a minimum pressure value (pmin) or the temperature (TKM) lies above a maximum saturation temperature value (Ts) with the pressure being outside a predefinable intended pressure range ([pu,po]).
    Type: Application
    Filed: February 10, 2004
    Publication date: August 19, 2004
    Applicant: BEHR GmbH & CO.
    Inventors: Walter Demuth, Rainer Heilig, Volker Kirschner, Martin Kotsch, Hans-Joachim Krauss, Hagen Mittelstrass, Harald Raiser, Michael Sickelmann, Karl-Heinz Staffa, Christoph Walter
  • Patent number: 6772518
    Abstract: The invention relates to a method for forming at least one flat-tube insertion slot in a header tube. A sawcut is introduced into the header tube during a sawing step, and the slot is configured, during a subsequent punching step, by means of a slot punch, which punches into the region of the sawcut. A rimmed opening can be configured during the punching step by using a slot punch with a larger width and/or length relative to the sawcut. The sawcut is preferably introduced to a depth less that the wall thickness of the header tube. The respective web region(s) between chamber of a multi-chamber header tube can be compressed during the punching operation to a level lower than that of a header-tube wall region functioning as a flat-tube insertion stop, in order to form a chamber-connecting duct.
    Type: Grant
    Filed: January 22, 2002
    Date of Patent: August 10, 2004
    Assignee: Behr GmbH & Co.
    Inventors: Walter Demuth, Wolfgang Geiger, Martin Kotsch, Hans-Joachim Krauss, Hagen Mittelstrass, Harald Raiser, Michael Sickelmann, Karl-Heinz Staffa, Christoph Walter
  • Patent number: 6751983
    Abstract: The invention relates to an air conditioning unit with a coolant circuit which consists of a compressor, an evaporator, a collector located at the low pressure side between the evaporator and the compressor and an inner heat transfer unit with a beat transfer channel located at the high pressure side and a low pressure side beat transfer channel. According to the invention, the inner heat transfer unit has an at least segmentally spiraling and/or spiral-shaped steps between the outer and inner pipe of a coaxial pipe system.
    Type: Grant
    Filed: October 1, 2002
    Date of Patent: June 22, 2004
    Assignee: Behr GmbH & Co.
    Inventors: Bernd Dienhart, Hans-Joachim Krauss, Hagen Mittelstrass, Karl-Heinz Staffa, Christoph Walter, Bernd Kallfass
  • Publication number: 20040103535
    Abstract: The invention relates to a method for forming at least one flat-tube insertion slot in a header tube. A sawcut is introduced into the header tube during a sawing step, and the slot is configured, during a subsequent punching step, by means of a slot punch, which punches into the region of the sawcut. A rimmed opening can be configured during the punching step by using a slot punch with a larger width and/or length relative to the sawcut. The sawcut is preferably introduced to a depth less that the wall thickness of the header tube. The respective web region(s) between chamber of a multi-chamber header tube can be compressed during the punching operation to a level lower than that of a header-tube wall region functioning as a flat-tube insertion stop, in order to form a chamber-connecting duct.
    Type: Application
    Filed: November 21, 2003
    Publication date: June 3, 2004
    Applicant: BEHR GmbH & Co.
    Inventors: Walter Demuth, Wolfgang Geiger, Martin Kotsch, Hans-Joachim Krauss, Hagen Mittelstrass, Harald Raiser, Michael Sickelmann, Karl-Heinz Staffa, Christoph Walter
  • Patent number: 6708508
    Abstract: The invention relates to a method of refrigerant level monitoring in a refrigerant circuit of an air-conditioning or heat-pump system having a compressor and a refrigerant which may, depending on the operating point, be operated in the supercritical range. The method includes standstill level monitoring with the compressor switched off and/or in-operation level monitoring with the compressor switched on. In the case of in-operation level monitoring, the refrigerant overheat (dTü) at the evaporator is registered and, in the event of excessive overheat, it is concluded that there is underfilling. At a standstill, the pressure and temperature of the refrigerant are registered, and it is concluded that there is an improper refrigerant filling level if the pressure (pKM) lies below a minimum pressure value (pmin) or the temperature (TKM) lies above a maximum saturation temperature value (TS) with the pressure being outside a predefinable intended pressure range ([pu,po]).
    Type: Grant
    Filed: December 11, 2001
    Date of Patent: March 23, 2004
    Assignee: Behr GmbH & Co.
    Inventors: Walter Demuth, Rainer Heilig, Volker Kirschner, Martin Kotsch, Hans-Joachim Krauss, Hagen Mittelstrass, Harald Raiser, Michael Sickelmann, Karl-Heinz Staffa, Christoph Walter
  • Patent number: 6601640
    Abstract: The invention relates to a heat transmission unit for a motor vehicle, comprising a fan cowling (12) and at least one heat exchanger (14) connected thereto. In order to provide an improved heat transmission unit which can be especially produced in an economical manner an which enables easy connection to the heat exchanger to the fan cowling especially during pre-assembly of the cooling module, the heat exchanger (14) is maintained on the fan cowling (12) by means of its manifolds (18, 20).
    Type: Grant
    Filed: January 11, 2002
    Date of Patent: August 5, 2003
    Assignee: Behr GmbH & Co.
    Inventors: Karl-Heinz Staffa, Hans-Joachim Krauss, Hagen Mittelstrass, Christoph Walter, Bernd Dienhart
  • Patent number: 6588223
    Abstract: An optimized CO2 air-conditioning system for a vehicle has individual components designed and/or matched to one another in such a way that if the high pressures in the high-pressure section deviate by up to ±30% from the optimum high pressures, the associated optimum performance figures are reduced by no more than 20%. The individual components include a controllable compressor, a gas cooler, an internal heat exchanger, an evaporator and an accumulator. As a result, a fixed throttle expansion member can be used between the high-pressure and low-pressure sections of the system.
    Type: Grant
    Filed: August 13, 2002
    Date of Patent: July 8, 2003
    Assignee: Visteon Global Technologies, Inc.
    Inventors: Bernd Dienhart, Hans-Joachim Krauss, Hagen Mittelstrass, Karl-Heinz Staffa, Christoph Walter, Jürgen Fischer, Michael Katzenberger, Karl Lochmahr
  • Patent number: 6546999
    Abstract: A flat tube for use in a heat exchanger includes a reversal bend section connected between parallel extending tube sections. The reversal bend section extends from a plane of the tube sections by a distance less than a width of the tube sections. The tube sections can be straight or serpentine. A plurality of the flat tubes can be stacked and connected to collector tubes to form a heat exchanger for use as an evaporator in a vehicle air conditioning system. Corrugated ribs are positioned between adjacent flat tubes for increased heat conduction.
    Type: Grant
    Filed: March 10, 2000
    Date of Patent: April 15, 2003
    Assignee: Visteon Global Technologies, Inc.
    Inventors: Bernd Dienhart, Hans-Joachim Krauss, Hagen Mittelstrass, Karl-Heinz Staffa, Christoph Walter, Jochen Schumm
  • Patent number: 6543239
    Abstract: An air-conditioning system operated with CO2 for a vehicle has a high-pressure section that is connected to the output of a compressor and includes a gas cooler, a low-pressure section that is connected to the suction side of the compressor and includes an evaporator, and an expansion member connecting the high-pressure section and the low-pressure section. The expansion member has a fixed restrictor with a throttle opening of predetermined length and diameter connected between an inlet from the high-pressure section and an outlet to the low-pressure section whereby under all operating conditions of the system, a pressure of refrigerant in the high-pressure section of the system is limited to values of less than 14 MPa. The restrictor can be connected in parallel with a pressure limiting valve and can include two or more different throttle openings that can be selectively connected for refrigerant flow.
    Type: Grant
    Filed: August 5, 2002
    Date of Patent: April 8, 2003
    Assignee: Visteon Global Technologies, Inc.
    Inventors: Bernd Dienhart, Hans-Joachim Krauss, Hagen Mittelstrass, Karl-Heinz Staffa, Christoph Walter, Michael Katzenberger, Karl Lochmahr, Werner Strauss
  • Patent number: 6523606
    Abstract: A heat exchanger block includes a plurality of block units, located one behind the other, each having a plurality of stacked tube units with tube ducts extending transverse to the block depth and height. The tube ducts are connected at ends to associated collector ducts extending in the block height direction. The tube units can be formed from a multichamber flat tube. At least one collector-duct connection is provided between adjacent block units to form a meandering flow path through the heat exchanger block. The heat exchanger block can be used as an evaporator in a motor vehicle air-conditioning system.
    Type: Grant
    Filed: March 24, 2000
    Date of Patent: February 25, 2003
    Assignee: Visteon Global Technologies, Inc.
    Inventors: Bernd Dienhart, Hans-Joachim Krauss, Hagen Mittelstrass, Karl-Heinz Staffa, Christoph Walter, Jochen Schumm