Patents by Inventor Walter Hefti

Walter Hefti 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: 5020924
    Abstract: The bearing unit comprises a plurality of bearing elements rotatable relative to each other. A shell encircles the plurality of bearing elements. A body of resiliently compressible material is located between the shell and the plurality of bearing elements and possesses a predetermined compressibility. This body of resiliently compressible material retains the plurality of bearing elements relative to the shell and permits free adjustment of the plurality of bearing elements relative to the shell within limits determined by the predetermined compressibility of the resiliently compressible material.
    Type: Grant
    Filed: January 19, 1989
    Date of Patent: June 4, 1991
    Assignee: Rieter Machine Works, Ltd.
    Inventors: Robert Demuth, Walter Hefti, Urs Keller, Daniel Hanselmann
  • Patent number: 4848686
    Abstract: A tube-supporting cradle mechanism for a filament, especially a yarn or thread take-up system is provided with a resiliently deformable body enabling relative adjustment of relatively rigid parts which adjoin the resiliently deformable body in order to permit line contact between a bobbin tube or its package wound thereupon, which is supported by the cradle, and a friction drive roll.
    Type: Grant
    Filed: December 18, 1986
    Date of Patent: July 18, 1989
    Assignee: Rieter Machine Works Ltd.
    Inventors: Robert Demuth, Walter Hefti, Urs Keller, Daniel Hanselmann
  • Patent number: 4781333
    Abstract: A package holder for use in winding yarn packages comprises at least one arm adapted to support a bobbin tube and pivotable about a first axis as a yarn package is formed on the tube. The arm is also pivotable about a second axis extending transversely to the first axis to make it possible to install or remove the bobbin tubes or packages. A first member is provided which is movable with the arm during the pivoting movement thereof about the first axis. A second member is engaged by the first member and is so mounted that relative movement of the first and second members occurs during the pivoting movement of the arm about the first axis.
    Type: Grant
    Filed: July 27, 1987
    Date of Patent: November 1, 1988
    Assignee: Maschinenfabrik Rieter AG
    Inventors: Walter Hefti, Urs Keller, Robert Ammann
  • Patent number: 4718615
    Abstract: A package holder for use in winding yarn packages comprises at least one arm adapted to support a bobbin tube and pivotable about a first axis as a yarn package is formed on the tube. The arm is also pivotable about a second axis extending transversely to the first axis to make it possible to install or remove the bobbin tubes or packages. A first member is provided which is movable with the arm during the pivoting movement thereof about the first axis. A second member is engaged by the first member and is so mounted that relative movement of the first and second members occurs during the pivoting movement of the arm about the first axis.
    Type: Grant
    Filed: March 24, 1986
    Date of Patent: January 12, 1988
    Assignee: Maschinenfabrik Rieter AG
    Inventors: Walter Hefti, Urs Keller, Robert Ammann
  • Patent number: 4695000
    Abstract: A device for winding up a thread or yarn or the like into a yarn package on a rotatable, conical bobbin tube comprises a drive roller which has an intermediate rotational element fixedly coupled to a drive shaft and two lateral rotational elements disposed laterally of the fixedly coupled intermediate rotational element and rotatably supported on the drive shaft. The lateral rotational elements are interconnected by a differential transmission. The differential transmission comprises a friction coupling. This affords the advantage of a strong reduction in the danger of damage to the yarn package in the event of blockage of one of the lateral rotational elements. Furthermore, the results of faulty manipulation of the drive roller during servicing or maintenance thereof is very substantially reduced.
    Type: Grant
    Filed: January 28, 1987
    Date of Patent: September 22, 1987
    Assignee: Maschinenfabrik Rieter AG
    Inventors: Walter Fretz, Walter Hefti
  • Patent number: 4641397
    Abstract: A drafting mechanism for spinning machines for drafting a staple fiber web, a staple fiber sliver or a staple fiber slubbing has at least an input roller pair, two intermediate roller pairs, and an output roller pair each having a lower roller and a pressure roller, a first group of support elements arranged to receive the lower rollers at their both ends and a second group of support elements arranged to receive the pressure rollers at their both ends, and the support elements receiving the lower rollers and/or the support elements receiving the pressure rollers are connectable to each other on both sides of the rollers by respective connecting elements.
    Type: Grant
    Filed: March 26, 1985
    Date of Patent: February 10, 1987
    Assignee: Maschinenfabrik Rieter AG
    Inventors: Giancarlo Mondini, Walter Hefti, Siegfried Kaufmann
  • Patent number: 4399589
    Abstract: In a cutting machine for a synthetic filament tow the filament tow 3 before passing between the cutting rolls 1/2 is traversed laterally to and fro. The present invention teaches, in which manner the traversing movement of the tow guide 5, moved to and fro using a grooved drum 10, is to be effected for obtaining a linear, i.e. optimum, fibre length diagram of the cut fibres. In particular, the mathematic formula for the shape of the guide groove 9, as unrolled in a plane, of the grooved drum 10 is given.
    Type: Grant
    Filed: July 13, 1981
    Date of Patent: August 23, 1983
    Assignee: Rieter Machine Works Ltd.
    Inventor: Walter Hefti