Patents by Inventor Manfred Schildmann

Manfred Schildmann 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: 10960923
    Abstract: The invention relates to a hydraulic steering facility for mobile systems, with a steering circuit for a steering facility and a working circuit for a working hydraulic system, whereby the steering circuit and the working hydraulic system are connected to a supply pump via a shared flow dividing valve and the flow dividing valve is connected to a load signal connection of the steering device. It is provided that the steering facility has an adjustable input choke that is connected via an inflow connection of the steering facility to the flow dividing valve, between the load signal connection and downstream of the input choke, a parallel circuit consisting of a choke and an adjustable second load signal choke is arranged, and the load signal connection is further connected via an adjustable first load signal choke to a return flow connection of the steering facility.
    Type: Grant
    Filed: July 10, 2018
    Date of Patent: March 30, 2021
    Assignee: Danfoss Power Solutions Parchim GmbH
    Inventors: Erhard Bergmann, Manfred Schildmann, Hartmut Vossberg
  • Publication number: 20190031233
    Abstract: The invention relates to a hydraulic steering facility for mobile systems, with a steering circuit for a steering facility and a working circuit for a working hydraulic system, whereby the steering circuit and the working hydraulic system are connected to a supply pump via a shared flow dividing valve and the flow dividing valve is connected to a load signal connection of the steering device. It is provided that the steering facility has an adjustable input choke that is connected via an inflow connection of the steering facility to the flow dividing valve, between the load signal connection and downstream of the input choke, a parallel circuit consisting of a choke and an adjustable second load signal choke is arranged, and the load signal connection is further connected via an adjustable first load signal choke to a return flow connection of the steering facility.
    Type: Application
    Filed: July 10, 2018
    Publication date: January 31, 2019
    Applicant: Hydraulik Nord Fluidtechnik GmbH & Co. KG
    Inventors: Erhard Bergmann, Manfred Schildmann, Hartmut Vossberg
  • Patent number: 5970708
    Abstract: In order to continuously change the transmission ratio between power-assisted steering mode and emergency steering mode and to maximize the flow of hydraulic oil in the power-assisted steering mode when the steering wheel is rapidly turned, a steering assembly is proposed which uses a common line which bypasses the metering pump, as a supply line for flow amplification during power-assisted operation and as a return line for changing the transmission ratio during emergency operation. This common line is connected to selected supply lines by way of throttles and with corresponding cylinder lines or with all cylinder lines by way of throttles. Steering devices of this type are employed in mobile equipment, in particular in slowly moving vehicles.
    Type: Grant
    Filed: October 30, 1997
    Date of Patent: October 26, 1999
    Assignee: Hydraulik Nord GmbH
    Inventors: Erhard Bergmann, Gerhard Voss, Manfred Schildmann
  • Patent number: 5887429
    Abstract: Conventional steering systems of this type have the disadvantage that the dynamic load signal flow is lossy which has a negative effect on the energy efficiency. Another disadvantage arises in steering systems with a closed-center design. When the steering cylinder is pulled by an external force, the steering cylinder moves in advance of the apportioned steering flow. In the present novel steering system, the adjusting angles of the primary adjustable throttles (12, 13, 14, 15, 16, 17) are matched in a novel way, so that in a steering range where the steering rotational speed is limited, the load signal flow is used for actuating the steering system. In this phase, the steering system then operates according to the open-center principle.
    Type: Grant
    Filed: August 1, 1997
    Date of Patent: March 30, 1999
    Assignee: Hydraulik Nord GmbH
    Inventors: Erhard Bergmann, Manfred Schildmann, Gerhard Voss
  • Patent number: 5850888
    Abstract: The invention changes over to another steering ratio automatically and very safely on the transition from servo to emergency operation. In the steering system, only a few of the lines (13) link the metering pump (10) to one of the cylinder connections (7, 8) and in each of the other lines (13') there is a changeover unit (16) which also links the lines (13) to the cylinder connections (7, 8) or the delivery connection (6) depending on the method of operation. These steering systems are used in mobile systems, especially slow-moving vehicles.
    Type: Grant
    Filed: September 3, 1996
    Date of Patent: December 22, 1998
    Assignee: Hydraulik Nord GMBG
    Inventors: Erhard Bergmann, Manfred Schildmann, Gerhard Voss
  • Patent number: 5771692
    Abstract: A steering system having a first auxiliary branch line (23, 24) connecting a main line (6) to a return port (12); with a load line (22) connecting the first auxiliary branch line to a load port (13) and dividing the first auxiliary branch line into first (24) and second (23) flow paths. The main line includes an adjustable input throttle (20). The first flow path (24) includes an adjustable load throttle (27) and a second throttle (26) in series. The adjustable input throttle and the adjustable load throttle act in a same direction. The purpose of this control circuit is to raise the load port pressure level, so as to prevent relatively high power losses.
    Type: Grant
    Filed: September 27, 1996
    Date of Patent: June 30, 1998
    Inventors: Erhard Bergmann, Manfred Schildmann, Gerhard Voss