Patents by Inventor Kurt Seifert

Kurt Seifert 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: 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: 4730785
    Abstract: Fuel injection nozzle for internal combustion engines, which includes a valve needle connected with a piston which limits a dampening chamber filled with fuel and connected with only one throttle passage with the flow path of the fuel. The dampening chamber is formed in a cap which is mounted on the piston. A pressure piece which is loaded by the fuel is guided in the bottom of the cap. The pressure piece pushes immediately against the piston during a prestroke and then comes into engagement with the cap. The pressure piece has a smaller diameter than that of the piston, so that the prestroke of the valve needle is more or less dampened at least at its lower speed and load range.
    Type: Grant
    Filed: December 5, 1986
    Date of Patent: March 15, 1988
    Assignee: Robert Bosch GmbH
    Inventor: Kurt Seifert
  • Patent number: 4572434
    Abstract: A fuel injection nozzle for internal combustion engines having a valve needle opening outward and connected with a piston which defines a damping chamber filled with fuel. Upon the opening stroke of the valve needle, the damping chamber communicates with the flow path of the fuel only via a throttling conduit. The damping chamber is formed in a cap, which is mounted upon the piston and centers itself on the piston. The cap is supported on the nozzle housing toward the side of the injection opening via a pre-stressed support spring, and the cap and the support spring are confined between stops attached to the housing. Therefore, the damping can be limited in a manner dependent on pressure or speed.
    Type: Grant
    Filed: December 9, 1983
    Date of Patent: February 25, 1986
    Assignee: Robert Bosch GmbH
    Inventor: Kurt Seifert
  • Patent number: 4531676
    Abstract: A fuel injection nozzle for internal combustion engines, having a valve needle arranged to open toward the outside and said valve needle further connected with a piston which defines a fuel-filled damping chamber, which communicates with the flow path of the fuel only via a throttle conduit during the opening stroke of the valve needle. The damping chamber is formed in a cap which is placed onto the piston. As a result, jamming of the elements in the radial direction is avoided. Furthermore, the piston may be embodied by the valve needle per se, resulting in a simple and space-saving construction. By means of the appropriate embodiment and supporting of the cap, the damping effect can be limited dependent on the stroke and/or the travel speed of the valve needle.
    Type: Grant
    Filed: September 22, 1982
    Date of Patent: July 30, 1985
    Assignee: Robert Bosch GmbH
    Inventors: Kurt Seifert, Karl Hofmann
  • Patent number: 4526323
    Abstract: A fuel injection nozzle for internal combustion engines having a hollow needle in which a valve needle is displaceably supported, which cooperates with an internal valve seat of the hollow needle. Associated with the valve needle are a valve spring and a stop attached to the housing, which restrain the valve needle with respect to the hollow needle as it moves in the opening direction, thus opening the valve. The closing movement of the hollow needle is limited by a stop on the nozzle body, which with a counterpart shoulder on the hollow needle efficaciously forms a shield with respect to the combustion chamber for the bearing gap between the hollow needle and the nozzle body. The hollow needle may advantageously be embodied as a closing member opening outward and cooperating with the nozzle body in order to control further injection openings.
    Type: Grant
    Filed: May 20, 1982
    Date of Patent: July 2, 1985
    Assignee: Robert Bosch GmbH
    Inventor: Kurt Seifert
  • Patent number: 4516729
    Abstract: A fuel injection nozzle for internal combustion engines having a valve needle which enters an intermediate position in a retarded fashion and subsequently reaches its final position quickly. The valve needle is coupled in a positively-engaged manner with a supplementary body which as a result of its mass and/or hydraulically damps the movement of the valve needle over the course of a first stroke portion. At the end of this stroke portion, the supplementary body strikes a shoulder attached to the housing, whereupon the valve needle after the attainment of a notably higher fuel pressure, is separated from the supplementary body and translated quickly into its open position. In special cases, it is also possible for two supplementary bodies to be provided, which are uncoupled one after another from the valve needle and then again recoupled to the valve upon the closure of the valve.
    Type: Grant
    Filed: September 22, 1982
    Date of Patent: May 14, 1985
    Assignee: Robert Bosch GmbH
    Inventors: Paul Fussner, Karl Hofmann, Iwan Komaroff, Katsuoki Itoh, Kurt Seifert, Dietrich Trachte, Wilhelm Vogel, Hans-Jorg Vogtmann
  • Patent number: 4442978
    Abstract: A fuel injection nozzle is proposed having a valve needle which opens in the direction of fuel flow and a throttle point controlled in accordance with the stroke of the valve needle which is loaded by at least two closing springs, in order to obtain a distinct pressure jump with respect to the required opening pressure when the throttle point is rendered ineffective. As a result, the throttle point is fully effective during idling and at relatively low partial loads and is only rendered ineffective when the supply of fuel is relatively great.
    Type: Grant
    Filed: July 21, 1982
    Date of Patent: April 17, 1984
    Assignee: Robert Bosch GmbH
    Inventor: Kurt Seifert
  • Patent number: 4417693
    Abstract: To provide for coupling the injection needle of a Diesel injection valve with an inertia mass, and thereby provide for speed damping of the movement of the valve, the pressurized Diesel fuel is applied to a chamber (20,68) in the valve body (10,12,14), which slidably retains the needle valve element (18) at a location downstream of the inertia mass, the inertia mass subdividing the chamber into a spring or pressure chamber (20) and a damping chamber (68) forming a dead, or storage chamber for fuel, the inertia mass being slidable in the second chamber and the clearance between the inertia mass and the walls of the chamber forming a throttled connection duct so that, upon command to opening movement, the needle valve element will engage, after a short dead distance (v), the inertia mass (62) which must move against the flow resistance through the throttled connection upon shifting of fuel between the first and second chamber and thus damping the speed of operation of the valve element.
    Type: Grant
    Filed: April 29, 1982
    Date of Patent: November 29, 1983
    Assignee: Robert Bosch GmbH
    Inventors: Paul Fussner, Karl Hofmann, Iwan Komaroff, Kurt Seifert, Dietrich Trachte, Wilhelm Vogel, Hans-Jorg Vogtmann
  • Patent number: 4410141
    Abstract: A fuel injection nozzle is proposed which opens toward the outside and functions with a valve needle and two springs, and further wherein a throttle restriction is effective after a first portion of the opening stroke, acting as a pre-stroke, and can be subsequently rendered ineffective. The two springs having a predetermined certain relationship to one another enable an abrupt increase in closing force after the pre-stroke. The first spring, embodied as a compression spring, acts in the closing direction; the second spring, having a smaller force than the first spring and acting counter to the closing direction, is rendered ineffective after the pre-stroke has been performed.
    Type: Grant
    Filed: November 21, 1980
    Date of Patent: October 18, 1983
    Assignee: Robert Bosch GmbH
    Inventor: Kurt Seifert
  • Patent number: 4407457
    Abstract: A fuel injection nozzle for internal combustion engines is proposed in which a valve needle receives an auxiliary needle in a blind bore opening toward the side on which injection occurs, and in which two injection locations each having at least one injection opening are controllable in accordance with the stroke, and in which the valve needle controls the passage of fuel from a pressure chamber of the injection nozzle selectively to the injection areas. The auxiliary needle is urged in the opening direction of the valve needle by a spring and is displaced in the flow direction at a first, lower fuel pressure, whereby it hydraulically separates the two injection areas. At a second, higher pressure the auxiliary needle is carried along as a drag member by the valve needle so as to reestablish communication between the two injection areas.
    Type: Grant
    Filed: November 30, 1981
    Date of Patent: October 4, 1983
    Assignee: Robert Bosch GmbH
    Inventor: Kurt Seifert
  • Patent number: 4394970
    Abstract: A fuel injection pump provided with an outwardly opening valve needle, on the valve needle head of which there is disposed an injection cone, tapered in the direction of the fuel flow in extension of a cylindrical section of the needle head, for the purpose of shaping the injection jet.
    Type: Grant
    Filed: February 6, 1981
    Date of Patent: July 26, 1983
    Assignee: Robert Bosch GmbH
    Inventors: Karl Hofmann, Kurt Seifert, Josef Jungbauer
  • Patent number: 4361286
    Abstract: A fuel injection nozzle having a valve needle opening outward is proposed in which the valve needle is suspended in place in the base of a spring plate embodied in the form of a cup.
    Type: Grant
    Filed: December 11, 1980
    Date of Patent: November 30, 1982
    Assignee: Robert Bosch GmbH
    Inventors: Karl Hofmann, Kurt Seifert
  • Patent number: 4344575
    Abstract: A fuel injection nozzle is proposed having a valve needle which opens in the direction of fuel flow and a throttle point controlled in accordance with the stroke of the valve needle which is loaded by at least two closing springs, in order to obtain a distinct pressure jump with respect to the required opening pressure when the throttle point is rendered ineffective. As a result, the throttle point is fully effective during idling and at relatively low partial loads and is only rendered ineffective when the supply of fuel is relatively great.
    Type: Grant
    Filed: November 26, 1980
    Date of Patent: August 17, 1982
    Assignee: Robert Bosch GmbH
    Inventor: Kurt Seifert
  • Patent number: 4096999
    Abstract: A fuel injection valve assembly for supplying a preliminary injection of fuel of a constant amount regardless of engine speed before the main injection of fuel begins comprising a spring biased, fuel supply pressure responsive, preliminary injection piston for the preliminary injection, a fuel supply pressure responsive loading piston for controlling the main injection fuel flow and a needle valve, both of the latter being biased oppositely by a common spring. Separate supply ducts for the preliminary and main fuel injections and the arrangement of the valve surfaces on the loading piston and needle valve enable the loading piston to be held closed and the needle valve to be opened by the pressure imposed on the preliminary injection piston and remain open long enough for the preliminary injection piston to travel its full stroke before closing and before the needle valve is opened for the main injection.
    Type: Grant
    Filed: November 29, 1976
    Date of Patent: June 27, 1978
    Assignee: Robert Bosch GmbH
    Inventors: Konrad Eckert, Karl Hofmann, Kurt Seifert