Patents by Inventor Edwin Harnischfeger

Edwin Harnischfeger 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: 10808381
    Abstract: A hydraulic lifting mechanism suspension has a main valve in the activation position whereof at least one hydraulic accumulator is connected to a connection line of the lifting mechanism suspension acting in the lifting direction or to working line of the lifting mechanism suspension acting in the lifting direction. The lifting mechanism suspension is deactivated via a deactivation position of the main valve, while at the same time a connection for recharging or filling the hydraulic accumulator is opened.
    Type: Grant
    Filed: May 7, 2019
    Date of Patent: October 20, 2020
    Assignee: Robert Bosch GmbH
    Inventors: Christian Goebel, Edwin Harnischfeger, Florian Herold, Rainer Biener, Wolfgang Hupp
  • Publication number: 20200002919
    Abstract: A hydraulic lifting mechanism suspension has a main valve in the activation position whereof at least one hydraulic accumulator is connected to a connection line of the lifting mechanism suspension acting in the lifting direction or to working line of the lifting mechanism suspension acting in the lifting direction. The lifting mechanism suspension is deactivated via a deactivation position of the main valve, while at the same time a connection for recharging or filling the hydraulic accumulator is opened.
    Type: Application
    Filed: May 7, 2019
    Publication date: January 2, 2020
    Inventors: Christian Goebel, Edwin Harnischfeger, Florian Herold, Rainer Biener, Wolfgang Hupp
  • Patent number: 7637103
    Abstract: Disclosed is a hydraulic control arrangement for damping wagging vibrations, wherein during operation a hydraulic cylinder of a lifting equipment can be connected to a hydraulic accumulator via a damping valve arrangement. The damping valve arrangement comprises a nozzle valve arrangement with two different nozzle cross-sections, the larger of which is active when filling the hydraulic accumulator and the smaller of which is active during adaptation of the hydraulic accumulator to the load pressure of the hydraulic cylinder.
    Type: Grant
    Filed: July 6, 2005
    Date of Patent: December 29, 2009
    Assignee: Bosch Rexroth AG
    Inventors: Erhard Karl, Edwin Harnischfeger
  • Publication number: 20080104866
    Abstract: Disclosed is a hydraulic control arrangement for damping wagging vibrations, wherein during operation a hydraulic cylinder of a lifting equipment can be connected to a hydraulic accumulator via a damping valve arrangement. The damping valve arrangement comprises a nozzle valve arrangement with two different nozzle cross-sections, the larger of which is active when filling the hydraulic accumulator and the smaller of which is active during adaptation of the hydraulic accumulator to the load pressure of the hydraulic cylinder.
    Type: Application
    Filed: July 6, 2005
    Publication date: May 8, 2008
    Inventors: Erhard Karl, Edwin Harnischfeger
  • Patent number: 7306071
    Abstract: A hydraulic steering apparatus with steering amount amplification is provided, wherein a metering device for supplying pressure medium to steering cylinders is actuated in accordance with an amount of rotation of the steering wheel. With the aid of a control block it is possible to deliver an additional pressure medium volume to the steering cylinders, wherein control of the control block is effected through the intermediary of a control circuit containing an effective control pressure that is substantially lower than the load pressure for transmitting the steering moment at the steering cylinder. A spring assembly for the control block is also provided, wherein two springs are arranged in parallel, one of which only takes effect following a predetermined stroke of the control element.
    Type: Grant
    Filed: March 13, 2003
    Date of Patent: December 11, 2007
    Assignee: Bosch Rexroth AG
    Inventors: Edwin Harnischfeger, Erhard Bergmann, Walter Scandella, Vincenzo Domenico Bollero
  • Patent number: 6938413
    Abstract: There is disclosed a hydraulic control arrangement for damping driving vibrations of a mobile machine, comprising a lifting cylinder supporting a working tool whose cylinder chambers can be connected to a fluid source or a tank via a control valve arrangement. The hydraulic control arrangement has a damping valve arrangement including a control valve in which a check valve is integrated through which a bottom-side chamber of the lifting cylinder is connectable to a hydraulic accumulator. In the pressure control function the accumulator can be connected to a tank so that the accumulator pressure is restricted to a maximum value.
    Type: Grant
    Filed: May 23, 2002
    Date of Patent: September 6, 2005
    Assignee: Bosch Rexroth AG
    Inventor: Edwin Harnischfeger
  • Publication number: 20050161278
    Abstract: What is disclosed is a hydraulic steering apparatus with steering amount amplification, wherein a metering device for supplying pressure medium to steering cylinders is actuated in accordance with an amount of rotation of the steering wheel. With the aid of a control block it is possible to deliver an additional pressure medium volume to the steering cylinders, wherein control of the control block in accordance with the invention is effected through the intermediary of a control circuit containing an effective control pressure that is substantially lower than the load pressure for transmitting the steering moment at the steering cylinder. There is moreover disclosed a spring assembly for the control block, wherein two springs are arranged in parallel, one of which only takes effect following a predetermined stroke of the control element.
    Type: Application
    Filed: March 13, 2003
    Publication date: July 28, 2005
    Applicant: BOSCH REXROTH AG
    Inventors: Edwin Harnischfeger, Erhard Bergmann, Walter Scandella, Vincenzo Bollero
  • Publication number: 20040216455
    Abstract: There is disclosed a hydraulic control arrangement for damping driving vibrations of a mobile machine, comprising a lifting cylinder supporting a working tool whose cylinder chambers can be connected to a fluid source or a tank via a control valve arrangement. The hydraulic control arrangement has a damping valve arrangement including a control valve in which a check valve is integrated through which a bottom-side chamber of the lifting cylinder is connectable to a hydraulic accumulator. In the pressure control function the accumulator can be connected to a tank so that the accumulator pressure is restricted to a maximum value.
    Type: Application
    Filed: January 20, 2004
    Publication date: November 4, 2004
    Inventor: Edwin Harnischfeger
  • Publication number: 20040088972
    Abstract: What is disclosed is a hydraulic control arrangement for attenuating travel vibrations of a mobile working tool, comprising a lift cylinder supporting a working tool, the cylinder chambers of which may be connected to a pressure medium source or to a tank via a control valve arrangement. The hydraulic control arrangement moreover includes an attenuation valve arrangement for connection of one cylinder chamber with an hydraulic accumulator and of the other cylinder chambers with a tank. In accordance with the invention, the attenuation valve arrangement includes a valve having a pressure limiting function and arranged between a check valve and the hydraulic accumulator, so that the pressure in the hydraulic accumulator may reliably be limited to a maximum value.
    Type: Application
    Filed: June 5, 2003
    Publication date: May 13, 2004
    Inventors: Edwin Harnischfeger, Manfred Mager
  • Patent number: 5802847
    Abstract: A hydraulic system for a mobile machine, in particular a wheel loader, has a longitudinal oscillation damping function. The hydraulic system has at least one hydraulic cylinder (13) with which a tool can be operated and whose inner space is divided by a piston (15) into two pressure chambers (17, 18); a stop valve (12) which connects one of the two pressure chambers (17, 18) to a hydraulic reservoir (42) which can be filled via a filling pipe; and a distributing or directional control valve (11) with a spool or slide valve (40) for the separate pressurization of the two pressure chambers (17, 18) in the hydraulic cylinder (13) and/or for connecting them to a tank (29). To facilitate low-cost and space-saving construction of a system of this type, the stop valve is incorporated in the distributing valve (11) in such a way that the hydraulic reservoir (42) and the first pressure chamber (17) of the hydraulic cylinder (13) can be connected to each other via the spool valve (40) of the distributing valve (11).
    Type: Grant
    Filed: November 1, 1996
    Date of Patent: September 8, 1998
    Assignee: Mannesmann Rexroth AG
    Inventor: Edwin Harnischfeger
  • Patent number: 5720168
    Abstract: A control system for a variable-displacement hydraulic pump having an adjustment device and being electrical current-adjustable as required for supplying pressure to a first hydraulic apparatus (13), and pressure-adjustable for supplying pressure to a second hydraulic apparatus (14), in which case the pressure rating and the setting of the pilot valve controlled by the second hydraulic apparatus (14) may be programmed by a control signal. The control system includes a first control valve (18) that can be actuated by the weight of the load of the first apparatus (13) and by a spring (23) when switching to a higher displacement, or by the pump pressure when switching to a lower displacement. The system further includes a second control valve (19) which can be exposed to a force corresponding to the control signal (25) when switching to a higher displacement, or to the pump pressure when switching to a lower displacement.
    Type: Grant
    Filed: August 9, 1996
    Date of Patent: February 24, 1998
    Assignee: Mannesmann Rexroth GmbH
    Inventor: Edwin Harnischfeger