Patents by Inventor Martin Doernhoefer

Martin Doernhoefer 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: 10975920
    Abstract: A synchronizer ring is made of steel and has a main body with a conical friction surface. A toothing and at least one blocking body project radially outward from the main body. The blocking body has an engagement section extending in the axial direction. The engagement section has a first edge, which runs approximately parallel to a first end face of the main body and has a first width extending in the circumferential direction, and two mutually opposite second edges extending from the first edge. To improve the durability of the synchronizer ring, the second edges have a convex curvature in a plan view of the engagement section. A second width extending in the circumferential direction between the second edges is greater than the first width at a depth spaced apart from the first edge.
    Type: Grant
    Filed: April 17, 2019
    Date of Patent: April 13, 2021
    Assignee: Diehl Metall Stiftung & Co. KG
    Inventors: Knut Erdmann, Murat Arbak, Martin Doernhoefer
  • Publication number: 20190242441
    Abstract: A synchronizer ring is made of steel and has a main body with a conical friction surface. A toothing and at least one blocking body project radially outward from the main body. The blocking body has an engagement section extending in the axial direction. The engagement section has a first edge, which runs approximately parallel to a first end face of the main body and has a first width extending in the circumferential direction, and two mutually opposite second edges extending from the first edge. To improve the durability of the synchronizer ring, the second edges have a convex curvature in a plan view of the engagement section. A second width extending in the circumferential direction between the second edges is greater than the first width at a depth spaced apart from the first edge.
    Type: Application
    Filed: April 17, 2019
    Publication date: August 8, 2019
    Inventors: KNUT ERDMANN, MURAT ARBAK, MARTIN DOERNHOEFER
  • Patent number: 10081171
    Abstract: A method for producing a synchronizer ring includes providing a ring body made of metal and having a conical connecting surface, providing a friction ring, corresponding to the connecting surface, made of a composite material of carbon fiber bound with a resin, adhesively bonding the friction ring to the connecting surface, and pyrolyzing exclusively an outer layer of the friction ring which is remote from the connecting surface.
    Type: Grant
    Filed: July 29, 2016
    Date of Patent: September 25, 2018
    Assignee: Diehl Metall Stiftung & Co. KG
    Inventors: Sabine Rahm, Knut Erdmann, Martin Doernhoefer
  • Publication number: 20170028699
    Abstract: A method for producing a synchronizer ring includes providing a ring body made of metal and having a conical connecting surface, providing a friction ring, corresponding to the connecting surface, made of a composite material of carbon fiber bound with a resin, adhesively bonding the friction ring to the connecting surface, and pyrolysing exclusively an outer layer of the friction ring which is remote from the connecting surface.
    Type: Application
    Filed: July 29, 2016
    Publication date: February 2, 2017
    Inventors: SABINE RAHM, KNUT ERDMANN, MARTIN DOERNHOEFER
  • Patent number: 8286776
    Abstract: A sheet-metal synchronizer ring for a synchronizing device has a conical ring body, an outer toothing for blocking the axial movement of a sliding sleeve, and at least one indexing tab which is bent in the axial direction and limits the rotation of the synchronizer ring in a synchronizer hub. The indexing tab has a tab widened portion on at least one side.
    Type: Grant
    Filed: November 9, 2010
    Date of Patent: October 16, 2012
    Assignee: Diehl Metall Stiftung & Co. KG
    Inventors: Martin Doernhoefer, Knut Erdmann, Meinrad Holderied
  • Publication number: 20120030929
    Abstract: The invention relates to a method for producing a component of a synchronization device for manual transmissions, in particular a synchronizer ring (1, 2, 3), wherein a round blank produced from metal is formed in a plurality of forming steps. In order to simplify the production process, it is proposed according to the invention that at least one of the forming steps is a hot forming step in which the round blank is partially heated to a temperature of more than 600° C. and is then formed in the partially heated forming portion.
    Type: Application
    Filed: May 6, 2010
    Publication date: February 9, 2012
    Applicant: Diehl Metall Stiftung & Co. KG
    Inventors: Marion Merklein, Martin Doernhoefer, Meinrad Holderied
  • Publication number: 20110056793
    Abstract: A sheet-metal synchronizer ring for a synchronizing device has a conical ring body, an outer toothing for blocking the axial movement of a sliding sleeve, and at least one indexing tab which is bent in the axial direction and limits the rotation of the synchronizer ring in a synchronizer hub. The indexing tab has a tab widened portion on at least one side.
    Type: Application
    Filed: November 9, 2010
    Publication date: March 10, 2011
    Applicant: DIEHL METALL STIFTUNG & CO. KG
    Inventors: Martin Dörnhöfer, Knut Erdmann, Meinrad Holderied