Patents by Inventor Andreas Förster

Andreas Förster 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: 20030008026
    Abstract: A pelletizing die includes a pelletizing die member with a die exit side exposed to cooling fluid and a die entry side for receiving polymer fed thereto. The die member has a plurality of polymer channels and a plurality of extrusion orifices connected to a respective one of the channels to form a extrusion orifice section. A heating medium system has additional heating medium conduits between channels and a supply and intermediate header for heating the channels (radially from each side) and providing once in and once out heating medium flow. The die member may be formed by high temperature brazing of components using coordinated solder (Ni based or gold-nickel) and component heat treatment temperature. A thin hard face coating may be provided on raised extrusion orifice ring faces around each extrusion orifice section.
    Type: Application
    Filed: July 9, 2001
    Publication date: January 9, 2003
    Inventors: Clifton T. Knight, Judeth Brannon Corry, Jurgen Blum, Andreas Grundmann, Dieter Bormann, Andreas Forster
  • Publication number: 20020112931
    Abstract: A telescopic vibration damper, comprising a pressure tube filled with a damping medium, in which a piston rod is arranged such that it can move axially, the pressure tube being axially displaceably guided in an intermediate tube. An annular chamber between the pressure tube and the intermediate tube is likewise filled with the damping medium, there being a flow connection between the pressure tube and the annular chamber, and a compensating chamber accommodates the displaced volume of the components that can be telescoped toward one another. The annular chamber formed by the intermediate tube and the pressure tube, and the pressure tube, are hydraulically separated from the compensating chamber.
    Type: Application
    Filed: January 14, 2002
    Publication date: August 22, 2002
    Applicant: ZFSachs AG
    Inventor: Andreas Forster
  • Patent number: 6428010
    Abstract: A sealing strip is provided for sealing a space between two parts of a machine, for example, a rotary engine. The two parts form a groove for receiving the sealing strip. The sealing strip includes a filler piece, at least one spring element, at least one sealing body and a separating element. The filler piece is divided into two filler piece parts along the longitudinal direction. The filler piece parts are capable of independent longitudinal displacement with respect to one another. A spring element is arranged between the filler piece parts for preloading the filler piece into the groove. Each sealing body is formed in a frame-like shape for surrounding an end of the filler piece. The separating element is arranged between the filler piece parts for separating the filler piece parts and extends longitudinally from an end of the divided filler piece to at least a point where a sealing body surrounds the divided filler piece.
    Type: Grant
    Filed: July 28, 2000
    Date of Patent: August 6, 2002
    Assignee: Mannesmann Sachs AG
    Inventors: Andreas Förster, Stefan Schiffler
  • Patent number: 6182687
    Abstract: A pressure-dependent valve, for use with an adjustable vibration damper comprising a piston rod arranged in an axially movable fashion in a cylindrical tube filled with damping fluid, is controlled by a pressure transducer pressurized via a pressure connection opening. The pressure-dependent valve includes a valve body axially movable relative to a valve surface. The valve body and valve surface together determine a valve passage cross-section. The pressure transducer is float-mounted in a pressure space and supported by at least one spring. One of the valve parts determining the valve passage cross-section is movable relative to the current position of the pressure transducer by an adjustment device.
    Type: Grant
    Filed: February 12, 1999
    Date of Patent: February 6, 2001
    Assignee: Mannesmann Sachs AG
    Inventors: Andreas Förster, Joachim Kühnel
  • Patent number: 6145809
    Abstract: An actuator for an electromagnetically adjustable valve having a drive unit which moves an adjustment element in at least one direction. The adjustment element is divided into at least two assemblies and includes a stroke setting that can be adjusted with respect to a defined operating position, within an adjustment process. The actuator has a reference plane on which a stop can be attached as a setting device. One assembly of the adjustment element enters into operative connection with the stop during the assembly process, and the other assembly of the adjustment element is held in a defined operating position by a positioning device. The two assemblies of the adjustment element can be connected using a securing device which is effective in at least one direction.
    Type: Grant
    Filed: October 8, 1999
    Date of Patent: November 14, 2000
    Assignee: Mannesmann Sachs AG
    Inventor: Andreas Forster
  • Patent number: 6135250
    Abstract: Disclosed is a hydropneumatic vibration damper of variable damping force, with a cylinder which is arranged between a piston rod guide and a bottom valve and in which a piston provided with at least one valve and connected to a piston rod subdivides the cylinder interior filled with damping fluid into a working space located on the piston rod side and a lower working space. A container surrounds the cylinder at a radial distance, thereby forming a compensating space which is filled with damping fluid and gas, while the lower working space can be connected hydraulically to the compensating space via a bottom valve and an electromagnetically actuable valve device is provided between the interior of the cylinder and the compensating space. The entire electromagnetically actuable valve device, taking effect between the interior of the cylinder, preferably the working space located on the piston rod side, and the compensating space, is arranged on that side of the bottom valve which is opposite the cylinder.
    Type: Grant
    Filed: May 27, 1998
    Date of Patent: October 24, 2000
    Assignee: Mannesmann Sachs AG
    Inventors: Andreas Forster, Georg Memmel
  • Patent number: 6082507
    Abstract: A rotary vibration damper having a housing, a stator having stator vanes and a rotor having vanes. The stator and the rotor are arranged in the housing so as to form at least two work chambers fillable with damping medium, which work chambers alternately change their volumes during the vibrational movement. At least one damping device is connected to at least one of the work chambers. At least one radial flow connection is arranged to connect the work chamber to the damping device. The at least one radial flow connection is arranged outside of the rotor vane and the stator vane.
    Type: Grant
    Filed: January 9, 1998
    Date of Patent: July 4, 2000
    Assignee: Mannesmann Sachs AG
    Inventor: Andreas Forster
  • Patent number: 6044939
    Abstract: The cylinder is filled with damping medium. The vibration damper also includes a damping valve which is active as a function of pressure. The damping force of the damping valve can be modified by means of an actuator against a spring force on a shutoff valve body. An admission valve with its own damping action is connected hydraulically in series with the damping valve, so that the action of the admission valve is superimposed on the action of the adjustable damping valve.
    Type: Grant
    Filed: June 19, 1997
    Date of Patent: April 4, 2000
    Assignee: Fichtel & Sachs
    Inventor: Andreas Forster
  • Patent number: 6035979
    Abstract: A damping valve for a vibration damper including a cylinder filled with damping medium. A piston rod with a piston is realized in the cylinder so that the piston rod can move axially and the piston can divide the cylinder into two working chambers. The damping valve is located inside a housing and is realized so that it can be adjusted by a solenoid in connection with an armature, which armature is guided in an insulator. A receptacle functions as part of the housing, which receptacle, by an insulator, separates the hydraulic part of the damping valve from the electrical part. A tube socket together with the housing holds the adjustable damping valve. As the insulator, at least one gasket or seal is used, which provides hydraulic and magnetic insulation between a cover of the housing and the receptacle.
    Type: Grant
    Filed: June 19, 1997
    Date of Patent: March 14, 2000
    Assignee: Fichtel & Sachs AG
    Inventor: Andreas Forster
  • Patent number: 6000508
    Abstract: A damping valve, in particular for a vibration damper, including a cylinder filled with damping medium in which a piston rod with a piston is housed. The piston rod can move axially and the piston divides the cylinder into two working chambers. The damping valve can be adjusted by means of a magnet coil in connection with an armature and has an emergency operating setting. A stop is provided for the valve position for the emergency operating setting. The position of the stop relative to the armature can be used to define a passage cross section for the emergency operating setting.
    Type: Grant
    Filed: June 19, 1997
    Date of Patent: December 14, 1999
    Assignee: Fichtel & Sachs AG
    Inventor: Andreas Forster
  • Patent number: 5937975
    Abstract: A vibration damper has a cylinder filled with damping medium. In the cylinder, a piston rod with a piston is realized so that the piston can move axially. The piston divides the cylinder into two working chambers. The vibration damper also has a damping valve. The damping force of the damping valve can be changed by a magnetic force generated by a magnetic coil inside a magnetic return body on an armature against a spring force of at least one spring. At least two regulating or adjustment parameters are provided to set at least two characteristics which differ from one another in terms of different flows to the magnetic coil. The characteristics can be set by a change of the effective spring characteristic with reference to a damping valve stroke position of the damping valve and also by the ability to regulate the magnetic conductivity of the magnetic return body by an actuator. The actuator can have a magnetic constriction, to which constriction a magnetic conductor body can be connected in parallel.
    Type: Grant
    Filed: June 20, 1997
    Date of Patent: August 17, 1999
    Assignee: Fichtel & Sachs AG
    Inventor: Andreas Forster
  • Patent number: 5740890
    Abstract: Intermediate tube for a vibration damper with adjustable damping force, having a tub socket which has an overlap with a valve seat body and forms a hydraulic connection to a switchable bypass valve. Inside the tube socket there is an intermediate ring which is supported by means of a support on at least one opening side of the tube socket and has a greater axial length than the tube socket. This intermediate ring has a region forming a snap fastening to permit the intermediate tube to snap into place with a portion of the tube socket.
    Type: Grant
    Filed: July 10, 1995
    Date of Patent: April 21, 1998
    Assignee: Fichtel & Sachs AG
    Inventor: Andreas Forster
  • Patent number: 5738191
    Abstract: A vibration damper having a pressure tube in which a piston with a piston rod is located so that the piston can move axially. The pressure tube is divided into upper and lower working chambers. The upper working chamber is connected by a hydraulic connection to the oil sump of an equalization chamber. The vibration damper also has at least one damping valve in the piston at least for the direction of flow from the upper working chamber to the lower working chamber, a port valve between a connection opening in the upper working chamber and the oil sump, a non-return valve in a bottom valve body which connects the lower working chamber with the equalization chamber and at least one additional damping valve in addition to the piston valve(s). In the insertion direction, the additional damping valve produces a damping which occurs as a function of the volume flow distribution.
    Type: Grant
    Filed: April 5, 1996
    Date of Patent: April 14, 1998
    Assignee: Fichtel & Sachs AG
    Inventor: Andreas Forster
  • Patent number: 5699885
    Abstract: Vibration damper with adjustable damping force, comprising a pressure tube filled with damping medium, in which a piston on an axially movable piston rod divides a work chamber into a chamber closer to the piston rod and a chamber farther from the piston rod, whereby there is a flow of damping medium between the two work chambers, which flow is divided into a main stream and side stream, a damping valve device consisting of a damping valve body with one main damping valve in each direction of flow, each of which is formed by a main stage valve body and a pilot stage valve which actuates the main stage valves, an adjustable actuator which controls a flow connection between a control chamber and a work chamber, and the main stage valve carries the flow of the main stream and the pilot stage valve carries the flow of the side stream in both directions of flow, characterized by the fact that the side stream in the pilot, stage valve flows through a non-return valve system, that the pilot stage valve has two contr
    Type: Grant
    Filed: July 6, 1995
    Date of Patent: December 23, 1997
    Assignee: Fichtel & Sachs AG
    Inventor: Andreas Forster
  • Patent number: 5651433
    Abstract: A fluid oscillation damper is provided with an electromagnetically controlled valve for varying the damping force of the oscillation damper. The electromagnetically controlled valve is housed within a compartment confined by two housing parts. A first housing part is fastened to a container of the oscillation damper A second housing part is fastened to the first housing part. Both housing parts are nonreleasably interconnected. The electromagnetically controlled valve is actuated by an electromagnetic coil. The electromagnetic coil is provided with a ferromagnetic core. This ferromagnetic core is constituted by a plurality of components. These components are assembled so as to reduce the magnetic resistance for the magnetic flux.
    Type: Grant
    Filed: July 11, 1995
    Date of Patent: July 29, 1997
    Assignee: Fichtel & Sachs AG
    Inventors: Alfred Wirth, Andreas Forster, Gunther Handke, Andreas Zietsch
  • Patent number: 5477949
    Abstract: A piston rod guide is provided for a shock absorber assembly, wherein the piston rod guide has a reflux passage for returning damping fluid back to the annular space formed between the cylinder walls of the shock absorber. The reflux passage is configured in a manner such that the returning damping fluid is returned to the annular space in a manner which substantially reduces foaming of the damping fluid within the cylinders.
    Type: Grant
    Filed: March 31, 1994
    Date of Patent: December 26, 1995
    Assignee: Fichtel & Sachs AG
    Inventors: Andreas Forster, Hubert Beck
  • Patent number: 5413196
    Abstract: According to an illustrative example of the present invention an oscillation damper is provided with a bypass interconnecting two fluid chambers. A main valve is provided within this bypass for allowing variation of the damping behavior of the oscillation damper. An electro-magnetic valve is used for controlling the hydraulic pressure acting onto the main valve. The electro-magnetic valve is biased toward an emergency position. The biasing force is obtained by two parallel acting springs. A first one of these springs is relatively weak, so that the valve can be transferred by low electric current in a magnetic coil against the action of the weak spring to a first operational position to be used during a major part of the operational time of the oscillation damper. By considerable increase of the electric current the valve can be further transferred into a further operational position which is desired only in exceptional situations.
    Type: Grant
    Filed: March 17, 1993
    Date of Patent: May 9, 1995
    Assignee: Fichtel & Sachs AG
    Inventor: Andreas Forster
  • Patent number: 5307710
    Abstract: The invention proposes a two-mass flywheel for the drive line of a motor vehicle. The two-mass flywheel comprises a torsional vibration damper with, distributed over the periphery, a plurality of coil springs (31, 31') which are braced on one another via sliding shoes (43). The sliding shoes (43) guide the springs (31) in a passage (29). End shoes (41) bearing on the end springs (31') and the sliding shoes (43) have extension pieces which prevent the springs (31, 31') bearing on the outer contours of the passage (23) at relatively high rotary speeds. The passage contains viscous lubrication so that in conjunction with slip-promoting coating on the end shoes (41) and sliding shoes (43) a very low basic friction is achieved.
    Type: Grant
    Filed: August 18, 1992
    Date of Patent: May 3, 1994
    Assignee: Fichtel & Sachs AG
    Inventors: Reinhard Feldhaus, Bernhard Schierling, Andreas Forster, Hilmar Goebel
  • Patent number: 5279183
    Abstract: According to an illustrative example of the invention, a flywheel is screwed to a crankshaft by a central bolt. The flywheel and the crankshaft are further provided with radially extending teeth in opposite annular contact faces. These teeth are engaged such as to center the flywheel with respect to the crankshaft and to permit torque transmission between the crankshaft and the flywheel. An angular positioning pin of the flywheel engages into a pin receiving bore of the crankshaft.
    Type: Grant
    Filed: April 19, 1991
    Date of Patent: January 18, 1994
    Assignee: Fichtel & Sachs AG
    Inventors: Andreas Forster, Peter Weber, Bernhard Schierling, Dieter Kolb, Harald Jeppe, Hilmar Goebel
  • Patent number: 5083981
    Abstract: The two-mass fly-wheel for a motor vehicle includes a first fly-wheel (3) rotatable about a rotation axis (1) and containing, axially on one side, a chamber (13) limited by a substantially cylindrical inner circumferential wall (11). A second fly-wheel (7) is coaxially mounted on the first fly-wheel (3). A lid (15) secured on the first fly-wheel (3) seals off the chamber (13) fluid-tightly from the second fly-wheel (7). In the chamber (13) a torsional vibration damper (9) is arranged of which the side disc (23) axially adjacent to the lid (15) is axially clamped in, outside the circumferential wall (11) of the chamber (13), between the lid (15) and an end wall (37) of the first fly-wheel (3).
    Type: Grant
    Filed: December 6, 1989
    Date of Patent: January 28, 1992
    Assignee: Fichtel & Sachs AG
    Inventor: Andreas Forster