Patents by Inventor Karl Hofmann

Karl Hofmann 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: 5984201
    Abstract: A fuel injection valve for internal combustion engines, having a valve member that is guided so that it can slide axially in a bore of a valve body. The valve member has a valve sealing face on one end which cooperates with a valve seat face on the valve body and this valve member, on an end remote from the valve sealing face, is acted on in the closing direction toward the valve seat by a valve spring, as well as having another adjusting member that controls a two-stage opening stroke course of the valve member. In order to control the two-stage opening stroke course of the valve member, the adjusting member is embodied as an adjustable stop, in which the valve member comes into at least indirect contact with after passing through a partial stroke and which in a first position, is locked in its initial position and in a second position, can be moved in the opening direction by means of the valve member.
    Type: Grant
    Filed: October 8, 1997
    Date of Patent: November 16, 1999
    Assignee: Robert Bosch GmbH
    Inventors: Karl Hofmann, Wolfram Gerwing
  • Patent number: 5978101
    Abstract: In an image detection device comprising at least one column arrangement consisting of photo detector elements linearly arranged in a row, an image field will be swung alternately across the photo detector elements in both longitudinal directions of the column arrangement. For time-correct summing and output of the detector signals, the photo detector elements of one column arrangement will be connected with a TDI arrangement. The TDI arrangement features a switch arrangement comprising several switches as well as a memory unit containing several memory cells. By appropriate control of the switch arrangement, its switches will be set such that the detector signals generated in the photo detector elements by one and the same image field pixel will be integrated into one and the same memory cell of the memory unit.
    Type: Grant
    Filed: December 7, 1995
    Date of Patent: November 2, 1999
    Assignee: Temic Telefunken microelectronic GmbH
    Inventors: Karl Hofmann, Reinhard Oelmaier
  • Patent number: 5934572
    Abstract: A fuel injection valve for internal combustion engines having, a valve member, which is axially displaceable in a valve body and which on one end has a valve sealing face with which it cooperates with a stationary valve seat in order to control an injection cross section, and having at least one valve spring, which urges the valve member in the direction of the valve seat and is braced on its other end on a stationary stop. To increase the spring force of the valve spring while the outer diameter remains the same, the windings of the valve spring, embodied as a helical spring, have a circular basic cross section (Y), which in a region pointing radially outward from the axis (X) of the valve spring has a ground face oriented parallel to the spring axis (X).
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: August 10, 1999
    Assignee: Robert Bosch GmbH
    Inventors: Karl Hofmann, Peter Kuegel, Ibrahim Oezyesilova
  • Patent number: 5917544
    Abstract: An arrangement and method for processing a signal field of sensor signals which originate from the individual sensor elements, for example photodetectors, of a plurality of sensor elements which are regularly spaced in an area and which are each surrounded by six adjacent sensor elements while forming a hexagonal structure. A differential amplifier compares a quantity representing the potential difference and a reference quantity forms a switching quantity (I.sub.Mo) on the output side. A switching comparator, on the input side, receives the switching quantity and, if this switching quantity exceeds the preselectable switching threshold, on the output side emits a switching pulse which causes the "off" switching condition. Four signal outputs 1, 2, 3, 4 as well as four signal inputs (I.sub.M1 I.sub.M2, I.sub.M3, I.sub.
    Type: Grant
    Filed: July 25, 1996
    Date of Patent: June 29, 1999
    Assignees: Daimler-Benz Aktiengesellschaft, Temic Telefunken Microelectronic GmbH
    Inventors: Gerald Sobotta, Willi Platz, Helmut Riedel, Karl Hofmann
  • Patent number: 5899385
    Abstract: A fuel injection valve for internal combustion engines that has a valve member which is guided axially displaceably in a guide bore of a valve body and which on an end toward the combustion chamber has a valve sealing face that cooperates with a valve seat face, formed on an end of the guide bore toward the combustion chamber, for controlling the communication between a high-pressure conduit in the valve body and at least one injection opening A diversion conduit in the valve member, by way of which diversion conduit the high-pressure conduit can be made to communicate with a relief chamber when the valve member has lifted from the valve seat face. Once the maximum opening stroke of the position of the valve member is reached, the diversion conduit is closed by a sealing face provided on the valve member, so that the entire supplied fuel quantity can attain injection.
    Type: Grant
    Filed: June 13, 1997
    Date of Patent: May 4, 1999
    Assignee: Robert Bosch GmbH
    Inventors: Karl Hofmann, Johann Warga, Thomas Kuegler, Peter Kuegel, Gungor Yurtseven
  • Patent number: 5727738
    Abstract: A fuel injection valve for internal combustion engines having a valve element which is axially displaceable in a valve body and a valve retention body, which is configured as a twin-spring retainer and in which are arranged first and second valve springs acting on the valve element in the closing direction. The first valve spring acts continually on the valve element via a pressure pin, whereas the second valve spring acts on the valve element only after a certain opening stroke motion of the valve element, which motion traversed forms a preliminary stroke (h1), and, by this motion, subdivides the opening stroke motion of the valve element into a preliminary stroke against the force of the first valve spring and a residual stroke against the force of the first and second valve springs.
    Type: Grant
    Filed: November 9, 1995
    Date of Patent: March 17, 1998
    Assignee: Robert Bosch GmbH
    Inventors: Karl Hofmann, Manfred Mack
  • Patent number: 5606190
    Abstract: A microelectronic circuit structure has a semiconductor layer and a dielectric layer that are arranged neighboring one another. The dielectric layer comprises a charge distribution localized close to the boundary surface to the semiconductor layer which effects a shift of the local semiconductor surface potential in the semiconductor layer. The charge distribution, in particular, is non-uniform in the plane parallel to the boundary surface to the semiconductor layer so that the shift of the local semiconductor surface potential is effected in a limited region. Structures having dimensions down to 10 nm can thereby be produced by driving charge carriers into the dielectric layer in the electrical field between a pointed metal tip and the semiconductor layer.
    Type: Grant
    Filed: May 19, 1994
    Date of Patent: February 25, 1997
    Assignee: Siemens Aktiengesellschaft
    Inventors: Karl Hofmann, Maximilian Schultz
  • Patent number: 5559353
    Abstract: A first MOS transistor and a second MOS transistor are connected in series with a first complementary MOS transistor and a second complementary MOS transistor that are connected in parallel with one another. The transistors are each realized as a vertical layer sequence that forms the source, channel and drain and that which has a sidewall at which a gate dielectric and a gate electrode are arranged. The complementary MOS transistors connected in parallel with one another are realized in a common layer sequence of the source, channel and drain. The layer sequences that form the series-connected transistors are arranged above one another. The circuit structure is manufactured by epitaxal definition of the layer sequences, such as by molecular beam epitaxy.
    Type: Grant
    Filed: November 1, 1994
    Date of Patent: September 24, 1996
    Assignee: Siemens Aktiengesellschaft
    Inventors: Lothar Risch, Thomas Vogelsang, Franz Hofmann, Karl Hofmann
  • Patent number: 5465907
    Abstract: A fuel injection nozzle for internal combustion engines having a nozzle body with a conical valve seat face and with a valve needle displaceable in the nozzle body, the valve needle having a closing cone cooperating with the seat face in valvelike fashion. To prevent the sealing cone from repeatedly covering the injection ports that begin at the seat face, which can be caused by the natural oscillation of the valve needle during the opening stroke, the valve needle is embodied to have a high natural frequency. To that end, the following segment that adjoins the guide segment guided in the nozzle body and that protrudes freely toward the seat face is embodied as conically tapered toward this seat face. The end segment of the valve needle that carries the closing cone may also be embodied as a thickened head.
    Type: Grant
    Filed: January 3, 1994
    Date of Patent: November 14, 1995
    Assignee: Robert Bosch GmbH
    Inventor: Karl Hofmann
  • Patent number: 5464158
    Abstract: A fuel injection nozzle for internal combustion engines for preinjection and main injection has an inwardly opening valve needle which is loaded by a single closing spring. After a prestroke (h.sub.v), in which the supply pressure in combination with the effective surface area of the valve needle controls the stroke, a stroke switchover to an interposed piston takes place, the effective surface area of the piston is less than that of the valve needle. Because the force of the piston that tenses the closing spring is reduced proportionally compared with the force of the valve needle, a flatter opening of the valve needle takes place after the prestroke (h.sub.v) than during the prestroke.
    Type: Grant
    Filed: May 2, 1994
    Date of Patent: November 7, 1995
    Assignee: Robert Bosch GmbH
    Inventor: Karl Hofmann
  • Patent number: 5443992
    Abstract: An insulating layer is grown on a principal face of a substrate that comprises a source terminal region. A first opening wherein the surface of the source terminal region is partially uncovered is provided in the insulating layer. A vertical layer sequence that comprises at least a channel region and a drain region for the MOS transistor is produced in the first opening by epitaxial growth of semiconductor material within situ doping. A second opening that is at least of a depth corresponding to the sum of the thicknesses of drain region and channel region is produced in the layer structure, a gate dielectric is applied on the surface thereof and a gate-electrode is applied on said gate dielectric.
    Type: Grant
    Filed: November 1, 1994
    Date of Patent: August 22, 1995
    Assignee: Siemens Aktiengesellschaft
    Inventors: Lothar Risch, Thomas Vogelsang, Franz Hofmann, Karl Hofmann
  • Patent number: 5413281
    Abstract: A fuel injection nozzle for internal combustion engines having a nozzle body, firmly fastened to a nozzle holder with an interposition of a shim, and a valve needle that is axially displaceable in the nozzle body and that is lifted by the fuel pressure, counter to a closing spring assembly for the injection of fuel. To lend the injection nozzle a slender form, the chamber receiving the closing spring assembly is disposed eccentrically to the nozzle axle and the fuel inlet conduit in the nozzle holder, specifically in the portion of the nozzle holder wall that is thicker as a result of the eccentricity. In order, moreover to transmit the closing force of the closing spring assembly to the valve needle without shear forces as much as possible, a pressure protrusion that transmits the closing force is guided in an aperture extending eccentrically to the nozzle axle (b). The protrusion is integrally joined with an adapter or with the valve needle.
    Type: Grant
    Filed: June 23, 1994
    Date of Patent: May 9, 1995
    Assignee: Robert Bosch GmbH
    Inventors: Karl Hofmann, Johann Warga
  • Patent number: 5271270
    Abstract: An injection nozzle for internal combustion engines has an electrical needle motion sensor, having a cable leading to an evaluation device. To dispose the terminals of the contact lugs of the needle motion sensor and the contact ends of the individual wires of the cable in such a way that they are shake-proof, relieved of tensile strain and protected against splashing water, they are encapsulated in a two-piece insulating shaped part, which is fixed in a recess of the holder body of the injection nozzle. The soldered terminals rest on support bases of pockets in the inner insulating shaped part, and the adjoining parts of the individual wires are bent back and guided in a U around retaining protrusions. The insulating shaped parts and the sheathed cable are fixed by a cover strip or by pins. The preferred field of application is injection nozzles for Diesel engines.
    Type: Grant
    Filed: February 21, 1992
    Date of Patent: December 21, 1993
    Assignee: Robert Bosch GmbH
    Inventors: Alfred Knauer, Ulli Lessing, Karl Hofmann, Kurt Seifert
  • Patent number: 5244152
    Abstract: A fuel injection nozzle for internal combustion engines has a nozzle body, a valve needle displaceably supported by the nozzle body, and a nozzle holder connected with the nozzle body and containing a spring chamber having a base. In the spring chamber are first and second closing springs arranged one after the other and acting on the valve needle one after the other. A first thrust pin penetrates the second closing spring. The first closing spring, which is farther away from the nozzle body, is supported at the base of the spring chamber and acts on the valve needle via the first thrust pin. The second closing spring is closer to the nozzle body and supported on a housing side and acts on the valve needle via discs and an intermediate bush. A second thrust pin penetrates the first closing spring and is arranged coaxially to the first thrust pin. The second closing spring is supported at the base of the spring chamber via the second thrust pin.
    Type: Grant
    Filed: July 27, 1992
    Date of Patent: September 14, 1993
    Assignee: Robert Bosch GmbH
    Inventor: Karl Hofmann
  • Patent number: 5161742
    Abstract: An injection nozzle provided with an inductive needle movement sensor is constructed in such a way that a coil winding of the sensor is faultlessly sealed against overflow oil without more space being required for the needle movement sensor than is required in a construction without a sealing of the coil winding against overflow oil. For this purpose, a coil core of the induction coil is lengthened into a lengthened portion of the chamber in a short-circuit body of the sensor, which chamber receives an induction coil, and a sealing ring seals the coil winding against a guide gap of the magneto armature in the short-circuit body. An annular gap between the short-circuit body and a bore hole wall in a nozzle holder receiving is sealed by means of a sealing ring. A clamping flange connected with the coil core directly contacts an adjacent annular flange of the coil body and the coil winding contacts connection wires on the other side of a clamping flange.
    Type: Grant
    Filed: May 6, 1991
    Date of Patent: November 10, 1992
    Assignee: Robert Bosch GmbH
    Inventors: Karl Hofmann, Roland Zucker, Bernhard Kaczynski, Ursula Schoedel, Alfred Knauer, Ulrich Lessing
  • Patent number: 5072706
    Abstract: A fuel injection arrangement for internal combustion engines, particularly for diesel engines, is indicated, in which the fuel injection is divided into an advance injection and a main injection for the purpose of noise reduction. An advance injection unit (27) is provided for the purpose of proportioning the advance injection quantity and a fuel injection pump of a conventional construction is provided for proportioning the main injection quantity. For an optimal design of the advance injection quantity with respect to noise reduction without influencing the main injection quantity, the advance injection unit (27) comprises a high-pressure storage (28), which is compressed to injection pressure, and at least one solenoid valve (30), which is controlled with respect to time. The advance and main injections are preferably effected via separate nozzle cross sections (21, 22).
    Type: Grant
    Filed: June 22, 1990
    Date of Patent: December 17, 1991
    Assignee: Robert Bosch GmbH
    Inventors: Ewald Eblen, Karl Hofmann, Alfred Schmitt, Max Straubel, Hung Truong-Canh
  • Patent number: 4909446
    Abstract: Fuel injection nozzle for internal combustion engines comprising an inwardly opening valve needle (14) and a nozzle bore hole (20) into which a throttle pivot (18) of the valve needle (14) dips during an initial lift. The throttle pivot (18) is provided with at least two flattened portions (30, 32 and 30, 32, 40, respectively) for forming preferred pass-through cross sections in the nozzle bore hole (20), wherein at least two flattened portions (30, 32 and 32, 40, respectively) end in different cross-sectional planes of the throttle pivot (18). Accordingly, a stepwise enlargement of the total cross section in the nozzle bore hole (20) can be achieved during the initial lift of the valve needle (14) with manufacturing methods which can be controlled in a favorable manner.
    Type: Grant
    Filed: August 17, 1988
    Date of Patent: March 20, 1990
    Assignee: Robert Bosch GmbH
    Inventors: Ewald Eblen, Rolf J. Giersch, Karl Hofmann
  • Patent number: 4801095
    Abstract: Fuel injection nozzle for internal combustion engines includes a nozzle element having a front cusp formed with a conical valve seat face. At least one injection hole is provided in the front cusp. The outer wall area of the front cusp which is disposed opposite to the valve seat face has a lower hardness than that of the inner wall area forming the valve seat face. When the injection hole extends from a pocket hole, preferably the outer wall area of the front cusp encompassing the picket hole has a lower hardness than that of the opposite disposed inner wall area. The intermediary center wall area preferably has a still lower hardness than the outer wall area. Thus, it is achieved that the front cusp of the nozzle element has a higher rigidity than in a known embodiment, without the valve seat face losing any hardness or that the protection of the outer wall area of the front cusp being unduly severly reduced against abrasive wear.
    Type: Grant
    Filed: December 15, 1986
    Date of Patent: January 31, 1989
    Assignee: Robert Bosch GmbH
    Inventors: Werner Banzhaf, Ewald Eblen, Heinrich Faber, Rolf J. Giersch, Karl Hofmann, Dieter Liedtke, Helmut Norberg
  • Patent number: 4784975
    Abstract: The insulating and stabiity characteristics of silicon dioxide gate oxide insulator for field effect transistors are enhanced by subjecting the silicon dioxide to an annealing in an ambient that contains a gaseous oxygen-containing species in an amount sufficient to provide a partial pressure from the oxygen-containing material of about 10.sup.-6 torr to about 10 torr during annealing temperatures of about 500.degree. C. to about 1200.degree. C. Such is carried out for a time sufficient to enhance the insulating and stability characteristics of the silicon dioxide insulator.
    Type: Grant
    Filed: October 23, 1986
    Date of Patent: November 15, 1988
    Assignee: International Business Machines Corporation
    Inventors: Karl Hofmann, Gary W. Rubloff, Donald R. Young
  • Patent number: 4768719
    Abstract: Fuel injection nozzle for internal combustion engines includes a first closing spring which acts continuously on the valve needle by means of a central pressure pin and, in addition, a second closing spring which acts continuously on the valve needle by means of a pressure piece after covering the distance of an initial stroke. The pressure piece is supported at the nozzle body by means of an intermediate bush during the initial stroke. The initial stroke is limited by means of the shoulders at the valve needle and the intermediate bush, whereas the total stroke is limited by means of the shoulders at the intermediate bush and the intermediate disk. Accordingly, the initial stroke can be adjusted very accurately to a desired magnitude merely by means of grinding the valve needle and does not change during the assembly of the injection nozzle.
    Type: Grant
    Filed: July 17, 1987
    Date of Patent: September 6, 1988
    Assignee: Robert Bosch GmbH
    Inventors: Max Straubel, Ewald Eblen, Paul Fussner, Gunter Kapolke, Edgar Schneider, Klaus Wolf, Werner Wagner, Karl Hofmann