Patents by Inventor Markus Lettmann

Markus Lettmann 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: 9828889
    Abstract: A camshaft for an internal combustion engine may include a shaft and at least one component that is joined to said shaft. The component may be connected via a joint surface of the component to a joint surface of the shaft. At least one of the joint surface of the component and the joint surface of the shaft may have a predefined roughness only partially on load-critical regions.
    Type: Grant
    Filed: July 18, 2012
    Date of Patent: November 28, 2017
    Assignee: Mahle International GmbH
    Inventors: Markus Lettmann, Ralf Rieger, Falk Schneider, Lutz Grunwald, Antonio Menonna, Stefan Steichele
  • Patent number: 9388713
    Abstract: A camshaft for an internal combustion engine may include a shaft and at least one component thermally joined thereto. The at least one component may be connected via a component-side joining face to a shaft-side joining face of the shaft. At least one of the component-side joining face and the shaft-side joining face may include a predefined roughness introduced and hardened via a laser. The predefined roughness may define at least one track composed of a plurality of individual laser spots. Each of the plurality of individual laser spots may include a center point arranged offset to each other. The plurality of individual laser spots may respectively be arranged to overlapping each other.
    Type: Grant
    Filed: July 18, 2013
    Date of Patent: July 12, 2016
    Assignee: Mahle International GmbH
    Inventors: Markus Lettmann, Ralf Rieger, Falk Schneider
  • Publication number: 20150184555
    Abstract: A camshaft for an internal combustion engine may include a shaft and at least one component thermally joined thereto. The at least one component may be connected via a component-side joining face to a shaft-side joining face of the shaft. At least one of the component-side joining face and the shaft-side joining face may include a predefined roughness introduced and hardened via a laser. The predefined roughness may define at least one track composed of a plurality of individual laser spots. Each of the plurality of individual laser spots may include a centre point arranged offset to each other. The plurality of individual laser spots may respectively be arranged to overlapping each other.
    Type: Application
    Filed: July 18, 2013
    Publication date: July 2, 2015
    Applicant: Mahle International GmbH
    Inventors: Markus Lettmann, Ralf Rieger, Falk Schneider
  • Publication number: 20140238321
    Abstract: A camshaft for an internal combustion engine may include a shaft and at least one component that is joined to said shaft. The component may be connected via a joint surface of the component to a joint surface of the shaft. At least one of the joint surface of the component and the joint surface of the shaft may have a predefined roughness only partially on load-critical regions.
    Type: Application
    Filed: July 18, 2012
    Publication date: August 28, 2014
    Applicant: Mahle International GmbH
    Inventors: Markus Lettmann, Ralf Rieger, Falk Schneider, Lutz Grunwald, Antonio Menonna, Stefan Steichele
  • Patent number: 8453615
    Abstract: The present invention relates to an adjustable camshaft (1), wherein inner and outer shafts (4, 2) connected securely with cams (5, 6) can be rotated relative to each other. In order to obtain this relative movement, at least one hydraulic adjusting device (3) is provided at one end of the camshaft (1), wherein a rotor (2) is rotatable in relation to a stator (19), and the rotor (20) and the stator (19) are each connected securely with one of the two shafts (2, 4). It is essential to the invention that the camshaft (1) is part of a prefabricated camshaft assembly, comprising at least the following components oriented relative to each other: camshaft (1) comprising inner shaft (4), outer shaft (2), cams (5, 6) and adjusting device (3) and a chain wheel (10).
    Type: Grant
    Filed: September 4, 2007
    Date of Patent: June 4, 2013
    Assignee: Mahle International GmbH
    Inventors: Markus Lettmann, Falk Schneider
  • Publication number: 20100108004
    Abstract: The present invention relates to an adjustable camshaft (1), wherein inner and outer shafts (4, 2) connected securely with cams (5, 6) can be rotated relative to each other. In order to obtain this relative movement, at least one hydraulic adjusting device (3) is provided at one end of the camshaft (1), wherein a rotor (2) is rotatable in relation to a stator (19), and the rotor (20) and the stator (19) are each connected securely with one of the two shafts (2, 4). It is essential to the invention that the camshaft (1) is part of a prefabricated camshaft assembly, comprising at least the following components oriented relative to each other: camshaft (1) comprising inner shaft (4), outer shaft (2), cams (5, 6) and adjusting device (3) and a chain wheel (10).
    Type: Application
    Filed: September 4, 2007
    Publication date: May 6, 2010
    Inventors: Markus Lettmann, Falk Schneider
  • Patent number: 7610890
    Abstract: The aim of the invention is to provide a reliable and inexpensive camshaft wherein the inner shaft and the outer shaft can be adjusted in a low-friction manner. For this purpose, a camshaft with cams that can be rotated in relation to each other, wherein at least one first cam (3) is rotatably received on the outer shaft (1), is permanently connected to the inner shaft (2) via at least one radial opening in the outer shaft (1). Means (10) for connecting a camshaft rotational drive are provided at the axial ends of the camshaft. The camshaft is also provided with a rotational drive (9) exerting radial supporting forces onto the camshaft.
    Type: Grant
    Filed: January 13, 2006
    Date of Patent: November 3, 2009
    Assignee: Mahle International GmbH
    Inventors: Markus Lettmann, Roland Schacherer, Falk Schneider
  • Patent number: 7597078
    Abstract: The present invention relates to a camshaft (1) having cams (3 and 4) rotatable with respect to one another about the camshaft axis (2) over limited circumferential angles, whereby an inside shaft (5) and an outside shaft (6) are arranged coaxially one inside the other. The cams (3 and 4) that are rotatable with respect to one another each consist of first cams (3) and second cams (4), whereby the first cams (3) are fixedly connected to the inside shaft (5) and the second cams (4) are fixedly connected to the outside shaft (6), each by means of a fixation device (8). It is essential to this invention that the first cams (3) each have a first through-bore (11) which is aligned with a respective second through-bore (12) in the inside shaft (5) when the first cam (3) is installed. In addition, the fixation device (8) is formed by two essentially identical fixation pins (10 and 10?) with respect to their axial longitudinal extent.
    Type: Grant
    Filed: December 21, 2006
    Date of Patent: October 6, 2009
    Assignee: Mahle International GmbH
    Inventors: Peter Kroos, Markus Lettmann, Falk Schneider
  • Patent number: 7503293
    Abstract: The present invention relates to an adjustable camshaft in which an inside shaft and an outside shaft, each being fixedly connected to cams, are mounted so they are rotatable in relation to one another. To produce the relative movement, a hydraulic adjusting mechanism is provided on one of the ends thereof; in the adjusting mechanism, first and second rotatable adjusting elements are each fixedly connected to one of the two shafts opposite one another. Adjacent to the adjusting mechanism, the outside shaft is fixedly connected to a first bearing ring supporting at least the outside shaft in a stationary first abutment.
    Type: Grant
    Filed: June 19, 2007
    Date of Patent: March 17, 2009
    Assignee: MAHLE International GmbH
    Inventors: Markus Lettmann, Falk Schneider
  • Publication number: 20080257290
    Abstract: The aim of the invention is to provide a reliable and inexpensive camshaft wherein the inner shaft and the outer shaft can be adjusted in a low-friction manner. For this purpose, a camshaft with cams that can be rotated in relation to each other, wherein at least one first cam (3) is rotatably received on the outer shaft (1), is permanently connected to the inner shaft (2) via at least one radial opening in the outer shaft (1). Means (10) for connecting a camshaft rotational drive are provided at the axial ends of the camshaft. The camshaft is also provided with a rotational drive (9) exerting radial supporting forces onto the camshaft.
    Type: Application
    Filed: January 13, 2006
    Publication date: October 23, 2008
    Applicant: MAHLE INTERNATIONAL GMBH
    Inventors: Markus Lettmann, Roland Schacherer, Falk Schneider
  • Publication number: 20070295296
    Abstract: The present invention relates to an adjustable camshaft in which an inside shaft and an outside shaft, each being fixedly connected to cams, are mounted so they are rotatable in relation to one another. To produce the relative movement, a hydraulic adjusting mechanism is provided on one of the ends thereof; in the adjusting mechanism, first and second rotatable adjusting elements are each fixedly connected to one of the two shafts opposite one another. Adjacent to the adjusting mechanism, the outside shaft is fixedly connected to a first bearing ring supporting at least the outside shaft in a stationary first abutment.
    Type: Application
    Filed: June 19, 2007
    Publication date: December 27, 2007
    Applicant: MAHLE International GmbH
    Inventors: Markus Lettmann, Falk Schneider
  • Publication number: 20070144469
    Abstract: The present invention relates to a camshaft (1) having cams (3 and 4) rotatable with respect to one another about the camshaft axis (2) over limited circumferential angles, whereby an inside shaft (5) and an outside shaft (6) are arranged coaxially one inside the other. The cams (3 and 4) that are rotatable with respect to one another each consist of first cams (3) and second cams (4), whereby the first cams (3) are fixedly connected to the inside shaft (5) and the second cams (4) are fixedly connected to the outside shaft (6), each by means of a fixation device (8). It is essential to this invention that the first cams (3) each have a first through-bore (11) which is aligned with a respective second through-bore (12) in the inside shaft (5) when the first cam (3) is installed. In addition, the fixation device (8) is formed by two essentially identical fixation pins (10 and 10?) with respect to their axial longitudinal extent.
    Type: Application
    Filed: December 21, 2006
    Publication date: June 28, 2007
    Inventors: Peter Kroos, Markus Lettmann, Falk Schneider
  • Publication number: 20050241796
    Abstract: For the production of piston pins having a hard peripheral area, a relatively inexpensive chill casting method is used. A chill form having a mold cavity for a piston pin is embedded in a casting mold, cast iron is poured into the mold cavity of the chill form, and then the peripheral area of the piston pin that results from this process is cooled by means of the chill form, is white-solidified, and thereby forms a hard wear-resistant surface.
    Type: Application
    Filed: April 29, 2004
    Publication date: November 3, 2005
    Inventors: Markus Lettmann, David Roth, Thomas Glas, Norbert Schneider, Giang Nguyen, Rodrigo Consentino