Patents by Inventor Josef Riedhammer

Josef Riedhammer 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: 6736048
    Abstract: A hydrostatic axial piston machine has a drum-like cylinder block which is supported in a manner fixed against rotation on a driving or output shaft and is provided concentrically and parallel to its center line with cylinder boreholes in which axially displaccable pistons are arranged which are supported via spherical heads on a slanting disk which is fixed to the housing and preferably adjustable in its slanting angle. The cylinder openings opposite the slanting disk sweep over roughly kidney-shaped low pressure and high pressure control openings of a control body, between which reversing regions with additional boreholes are located. To control the additional boreholes, which influence the pressure increase or the pressure drop on the passing of the cylinder openings over the reversing regions, in dependence on the operating states, a borehole opens at least in a reversing region of the control body which is connected to the high pressure side or the high pressure control opening by a line.
    Type: Grant
    Filed: July 18, 2001
    Date of Patent: May 18, 2004
    Assignee: Liebherr Machines Bulle SA
    Inventors: Josef Riedhammer, Erich Eckhardt, Franz-Josef Schwede
  • Publication number: 20020108489
    Abstract: A hydrostatic axial piston machine has a drum-like cylinder block which is supported in a manner fixed against rotation on a driving or output shaft and is provided concentrically and parallel to its center line with cylinder boreholes in which axially displaccable pistons are arranged which are supported via spherical heads on a slanting disk which is fixed to the housing and preferably adjustable in its slanting angle. The cylinder openings opposite the slanting disk sweep over roughly kidney-shaped low pressure and high pressure control openings of a control body, between which reversing regions with additional boreholes are located. To control the additional boreholes, which influence the pressure increase or the pressure drop on the passing of the cylinder openings over the reversing regions, in dependence on the operating states, a borehole opens at least in a reversing region of the control body which is connected to the high pressure side or the high pressure control opening by a line.
    Type: Application
    Filed: July 18, 2001
    Publication date: August 15, 2002
    Inventors: Josef Riedhammer, Erich Eckhardt, Franz-Josef Schwede
  • Patent number: 5046403
    Abstract: An axial piston machine has a housing with a cover, a swash plate located within the housing and an elongated rotary shaft extending through the swash plate and the housing with an end in the housing cover. A cylindrical drum is connected to the shaft for rotation therewith and one end of the cylindrical drum abuts against a surface of a control member located in the housing adjacent to the housing cover. A number of concentrically arranged cylindrical passages are formed in the cylindrical drum and a longitudinally moveable hollow piston is located in each cylindrical passage. A slide shoe is located at one end of each piston and each slide shoe is in working connection with the swash plate. Each slide shoe has a slide shoe plate, a slide shoe neck and a slide shoe head connected to one of the pistons. The face of each slide shoe plate which is opposed to the swash plate is in contact with an annular, spring-loaded retaining plate which is provided with a number of concentrically arranged recesses.
    Type: Grant
    Filed: August 28, 1990
    Date of Patent: September 10, 1991
    Assignee: Linde Aktiengesellschaft
    Inventor: Josef Riedhammer
  • Patent number: 4520712
    Abstract: A rotating drum-shaped cylinder block with pistons longitudinally displaceable in the cylinder bores is mounted in the housing of a reciprocating-piston pump of inclined-disc construction. The cylinder block is fitted on the free end of a rotating driving shaft which, in a median zone along its length, is mounted on two roller bearings in a bearing box which is completely sealed off from the machine housing. The pistons are supported in piston shoes on a stationary inclined disc the inclined position of which can be adjusted in the machine housing. For the purpose of sealing off the machine housing from the bearing box, there are slide-ring sealing means composed of a rotating ring secured to the driving shaft and of a stationary ring in the machine housing.
    Type: Grant
    Filed: November 1, 1983
    Date of Patent: June 4, 1985
    Assignee: Hermann Hemscheidt Maschinenfabrik GmbH & Co.
    Inventors: Reiner Hovorka, Josef Riedhammer
  • Patent number: 4388941
    Abstract: The invention relates to a device for producing a control pressure which corresponds to a rotary speed imparted to a shaft of a pump which is a part of the device. The device includes a measuring orifice formed by a fixed throttle and a control orifice formed by piston arrangement operating as a controlled throttle. The controlled throttle is responsive to oppositely acting pressures from opposite sides of the fixed throttle. The controlled throttle is in series with a fixed discharge throttle and the control pressure is tapped from between the controlled throttle and the discharge throttle.
    Type: Grant
    Filed: November 5, 1981
    Date of Patent: June 21, 1983
    Assignee: Danfoss A/S
    Inventor: Josef Riedhammer
  • Patent number: 3946561
    Abstract: A control device for connection between a hydropump and a hydromotor of a hydraulic system, to provide a control pressure for regulating operation of the system, has a valve housing accommodating a displaceable valve member formed to provide a throttling passageway between an inlet and a main outlet of the housing. Fluid flow through the throttle tends to move the valve member to open a connection between the inlet and a control pressure outlet of the housing, against the action of a resilient biasing arrangement and a force produced on the member in dependence upon the control pressure itself. The action of the biasing arrangement, however, is variable, enabling the device to be designed in accordance with a desired fluid-pressure/flow rate relationship.
    Type: Grant
    Filed: December 23, 1974
    Date of Patent: March 30, 1976
    Assignee: Hydromatik GmbH
    Inventor: Josef Riedhammer
  • Patent number: 3932993
    Abstract: Apparatus for adjusting a hydraulic machine driven by an adjustable driving motor comprises an adjustment motor which adjusts the machine in one sense under one fluid control input dependent upon actual driving motor speed and in an opposite sense under an opposing such input supplied at a control outlet of a pressure control valve device in dependence upon the position of a valve slide thereof urged by the first input against a biasing force selectively adjustable in dependence upon desired driving motor speed. When the actual speed falls sufficiently relative to the desired speed, the slide travels from one position, blocking flow from a fluid inlet of the valve device to its control outlet, to another position allowing such flow and also allowing the second input thus produced to act on the slide, in the same direction as the first does, until the slide returns to its initial position.
    Type: Grant
    Filed: December 11, 1974
    Date of Patent: January 20, 1976
    Assignee: Hydromatik GmbH
    Inventor: Josef Riedhammer