Patents by Inventor Manfred Hoffmann

Manfred Hoffmann 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: 4663381
    Abstract: Viscoelastic plastics materials having a dynamic elasticity modulus of 10.sup.7 to 10.sup.10 Nm.sup.-2 and a loss factor of at least 5 are used for the manufacture of motor vehicle parts, such as wheel housing parts, instrument panels, and door panels, in order to reduce interior noise.
    Type: Grant
    Filed: November 27, 1984
    Date of Patent: May 5, 1987
    Assignee: Dr. Alois Stankiewicz GmbH
    Inventors: Ehrenfried Blumel, Heinemann Gahlau, Manfred Hoffmann, Klaus Wittenmayer, Thomas Stankiewicz, Christoph Kittel
  • Patent number: 4633796
    Abstract: A feed device on a sewing machine having a feeder which is firmly connected with a horizontal shaft which is displaceably mounted in a feed rocker mounted fixed in a housing, and having a drive for the longitudinal axial movement of the shaft. For the reduction and simplification of the drive for the longitudinal movement of the shaft, this drive is arranged directly on the feed rocker. In addition, the horizontal shaft has a gear system with which a gear segment cooperates which together with its drive elements is mounted on a flange firmly connected with the feed rocker. The drive occurs via a step motor which is secured on a flange plate of the feed rocker lever.
    Type: Grant
    Filed: August 23, 1985
    Date of Patent: January 6, 1987
    Assignee: Pfaff Haushaltmaschinen
    Inventors: Manfred Hoffmann-Glewe, Dieter Prause
  • Patent number: 4582656
    Abstract: A method of producing molded articles from polyolefin molding compositions crosslinked by irradiation, to which molding composition is added, prior to irradiation, by mixing and/or copolymerizing, from 0.3 to 20 percent by weight of vinylacetate, optionally in a form as pre-copolymerized with a polyolefin. The occurence of undesirable accumulations and discharges of electrical charge concentrations and/or the undesirable foaming of the polyolefin molded articles will thus be suppressed.
    Type: Grant
    Filed: August 6, 1982
    Date of Patent: April 15, 1986
    Assignee: Hewing GmbH & Co.
    Inventor: Manfred Hoffmann
  • Patent number: 4574915
    Abstract: In order to subject sound-emitting surfaces of motor vehicles to localized interference with the sound field, for example, sound obstruction and attenuation, it is already known to insulate the region of the sound sources against noise by cladding the passenger space from within at the relevant point of the wall to be insulated by application of a heavy layer and of a resilient layer which, if necessary, is impregnated with a sound-attenuating material. However, limits are imposed on a sound-insulating cladding of this kind even when further sound-reducing materials are applied, as the transmission of sound energy to the interior space of the motor vehicle then takes place in other ways.In order to remedy this, at least one sound sink is subjected to intensified sound absorption by providing on the wall (2,3) a sound-insulating cladding (6/7). Specifically this cladding comprises a resilient layer (6) preferably made of foam material or fleece which is covered by a heavy layer (7).
    Type: Grant
    Filed: December 11, 1984
    Date of Patent: March 11, 1986
    Assignee: Dr. Alois Stankiewicz GmbH
    Inventors: Heinemann Gahlau, Manfred Hoffmann, Klaus Wittenmayer
  • Patent number: 4536266
    Abstract: Method for the fluorination of a surface layer of articles molded from plastic, vulcanized rubber or other such macromolecular substances by the exposure of at least a part of the article's surface to a fluorine-yielding liquid in a controllable reaction, the liquid consisting of a solvent or solvent mixture containing dissolved elemental fluorine. Suitable solvents are especially halogen hydrocarbons in accordance with DIN 8962, which are liquid within a temperature range from -30.degree. C. to +10.degree. C., but also water and solvents having perfluoroalkyl groups. The liquid, in which a fluorine concentration between 0.5.times.10.sup.-3 and 1.times.10.sup.-2 mol/l is established by the introduction of fluorine diluted with inert gas, is used to treat the articles for about 20 seconds to 30 minutes; the fluorine can be activated if desired. The liquid can additionally contain sulfur dioxide, oxygen, carbon monoxide, chlorine, bromine, or mixtures thereof.
    Type: Grant
    Filed: December 7, 1983
    Date of Patent: August 20, 1985
    Assignee: Hewing GmbH & Co.
    Inventors: Claus Bliefert, Hans-Michael Boldhaus, Manfred Hoffmann
  • Patent number: 4001157
    Abstract: Aqueous suspensions of polyolefin fibrids are prepared. To avoid foam formation and improve fiber-bonding, small amounts of anionic agents are added to the suspensions. The suspensions are suitable for the manufacture of paper-like or textile-like web structures distinguished by very good fiber bonding and good initial wet strength.
    Type: Grant
    Filed: November 19, 1975
    Date of Patent: January 4, 1977
    Assignee: BASF Aktiengesellschaft
    Inventors: Bruno Sander, Eckhard Bonitz, Heinz Berbner, Manfred Hoffmann
  • Patent number: 3992344
    Abstract: Aqueous suspensions of polyolefin fibrids are prepared. To avoid foam formation and improve fiberbonding, small amounts of anionic agents are added to the suspensions. The suspensions are suitable for the manufacture of paper-like or textile-like web structures distinguished by very good fiber bonding and good initial wet strength.
    Type: Grant
    Filed: November 19, 1975
    Date of Patent: November 16, 1976
    Assignee: BASF Aktiengesellschaft
    Inventors: Bruno Sander, Eckhard Bonitz, Heinz Berbner, Manfred Hoffmann
  • Patent number: 3985488
    Abstract: A material guide jaw, for two co-operating rolls of a rolling mill or calender, particularly for processing rubber or synthetic plastics material, comprising a jaw plate which forms a guide for the material and is so mounted on an intermediate plate which is mounted on a base plate that the jaw plate can be adjusted in three different ways while remaining in the same plane.
    Type: Grant
    Filed: November 10, 1975
    Date of Patent: October 12, 1976
    Assignee: Hermann Berstorff Maschinenbau GmbH
    Inventor: Manfred Hoffmann
  • Patent number: 3960794
    Abstract: A process for the manufacture of nonfoaming aqueous suspensions of polyolefin fibrids using suitable dispersing agents. These are obtained by polycondensation of 1 mole of melamine, from 1.8 to 3 moles of formaldehyde and from 0.1 to 0.5 molar portions of amino carboxylic acids or alkali metal salts thereof. Very small quantities of said dispersing agents are sufficient to finely disperse the hydrophobic polyolefin fibrids in water and to prevent the formation of foam in the manufacture of web structures of a paper-like and textile-like nature. The aqueous suspensions of polyolefin fibrids may also contain cellulose fibers.
    Type: Grant
    Filed: September 3, 1974
    Date of Patent: June 1, 1976
    Assignee: BASF Aktiengesellschaft
    Inventors: Bruno Sander, Heinz Berbner, Manfred Hoffmann
  • Patent number: 3950293
    Abstract: Aqueous suspensions of polyolefin fibrids are prepared. To avoid foam formation and improve fiberbonding, small amounts of anionic agents are added to the suspensions. The suspensions are suitable for the manufacture of paper-like or textile-like web structures distinguished by very good fiber bonding and good initial wet strength.
    Type: Grant
    Filed: October 17, 1974
    Date of Patent: April 13, 1976
    Assignee: BASF Aktiengesellschaft
    Inventors: Bruno Sander, Eckhard Bonitz, Heinz Berbner, Manfred Hoffmann
  • Patent number: 3938026
    Abstract: The invention relates to a circuit arrangement for the simultaneous ignition of a plurality of thyristors. Control paths of the thyristors are each connected to a secondary winding of a pulse transformer by way of a separate full-wave rectifier, an alternating current of higher frequency being supplied to the primary winding of the pulse transformer by a control current amplifier. In order to obtain a continuous flow of control current when a control signal is given, it is provided, according to the invention, that there is connected to the control path of each thyristor the series arrangement of a storage reactance coil and an uncontrolled diode poled in the direction of the gate current, and that the output of the full-wave rectifier is connected to this uncontrolled diode.
    Type: Grant
    Filed: November 4, 1974
    Date of Patent: February 10, 1976
    Assignee: Siemens Aktiengesellschaft
    Inventors: Manfred Hoffmann, Jakob Schenk, Karl-Friedrich Leowald