Patents by Inventor Carl Hoffmann

Carl Hoffmann 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: 11364611
    Abstract: A chiseling hand-held power tool having a tool holder for holding a tool on a working axis, an electric motor, and a striking mechanism. The striking mechanism has an excitation piston coupled to the motor, a striker guided on the working axis and a pneumatic chamber closed by the excitation piston and the striker for coupling a movement of the striker to the excitation piston. The rotational speed of the electric motor corresponds to at least 20 times the striking rate of the striking mechanism.
    Type: Grant
    Filed: December 20, 2019
    Date of Patent: June 21, 2022
    Assignee: Hilti Aktiengesellschaft
    Inventors: Christian Schallert, Jürgen Pritz, Marcel Wondra, Carl Hoffmann, Walter Vallaster
  • Publication number: 20210402583
    Abstract: A chiselling hand-held power tool having a tool holder for holding a tool on a working axis, an electric motor, and a striking mechanism. The striking mechanism has an excitation piston coupled to the motor, a striker guided on the working axis and a pneumatic chamber closed by the excitation piston and the striker for coupling a movement of the striker to the excitation piston. The rotational speed of the electric motor corresponds to at least 20 times the striking rate of the striking mechanism.
    Type: Application
    Filed: December 20, 2019
    Publication date: December 30, 2021
    Inventors: Christian SCHALLERT, Jürgen PRITZ, Marcel WONDRA, Carl HOFFMANN, Walter VALLASTER
  • Patent number: 8696477
    Abstract: A method for manufacturing a thread-forming screw having a shank and a thread formed in one piece with the shank and region-wise circumferentially arranged on the shank, is disclosed. After the formation of the thread on the shank, a plurality of recesses is subsequently stamped into the thread. Then, a plurality of compact cutting elements is welded into the recesses in the thread, where the cutting elements are made of a hard material and have a hardness greater than the hardness of the thread. Additionally, a stamping device for carrying out the method is also disclosed.
    Type: Grant
    Filed: December 16, 2009
    Date of Patent: April 15, 2014
    Assignee: Hilti Aktiengesellschaft
    Inventors: Franz Huber, Martin Pleil, Carl Hoffmann, Andreas Vorhauer, Simon Oppeneiger, Berthold Aumueller, Georg Oberndorfer, Juergen Gahn, Corinna Achleitner
  • Publication number: 20100216560
    Abstract: A method for manufacturing a thread-forming screw having a shank and a thread formed in one piece with the shank and region-wise circumferentially arranged on the shank, is disclosed. After the formation of the thread on the shank, a plurality of recesses is subsequently stamped into the thread. Then, a plurality of compact cutting elements is welded into the recesses in the thread, where the cutting elements are made of a hard material and have a hardness greater than the hardness of the thread. Additionally, a stamping device for carrying out the method is also disclosed.
    Type: Application
    Filed: December 16, 2009
    Publication date: August 26, 2010
    Applicant: Hilti Aktiengesellschaft
    Inventors: Franz Huber, Martin Pleil, Carl Hoffmann, Andreas Vorhauer, Simon Oppeneiger, Berthold Aumueller, Georg Oberndorfer, Juergen Gahn, Corinna Achleitner
  • Patent number: 7703644
    Abstract: A process for manufacturing a sliding plate for a valve closure on metallurgical melt containers may include forming the sliding plate by: integrating in a pressing procedure with a press, a pre-pressed annular insert made of a refractory ceramic material in a base body made of a refractory ceramic material; and removing the sliding plate from the press, resulting in an annular gap between a circumferential surface of the insert and a corresponding surface of the base body. The process may also include impregnating a transition area including the annular gap between the insert and the base body with an impregnation agent, and tempering the plate at temperatures between 200° C. and 700° C. to cause the impregnation agent to create a non-positive direct connection between the base body and the insert.
    Type: Grant
    Filed: September 16, 2005
    Date of Patent: April 27, 2010
    Assignee: Refractory Intellectual Property GmbH & Co. KG
    Inventors: Reinhard Ehrengruber, Carl Hoffmann, Robert Sherriff
  • Publication number: 20070241486
    Abstract: The invention relates to a sliding plate for a valve closure on metallurgical melt containers.
    Type: Application
    Filed: September 16, 2005
    Publication date: October 18, 2007
    Applicant: REFRACTORY INTELLECTUAL PROPERTY GMBH & CO. KG
    Inventors: Reinhard Ehrengruber, Carl Hoffmann, Robert Sherriff
  • Patent number: 5089194
    Abstract: To produce Al.sub.2 O.sub.3 -containing ceramic film casting mixtures for thin-film circuits, unground, calcined alumina with low primary particle size and high reactivity is ground, optionally together with a solvent mixture, then the binder or a mixture of a plurality of different binders and the plasticizer or a mixture of a plurality of different plasticizers are added and the mixture is ground again until the alumina reaches a particle size of 2-10 .mu.m. The alumina, optionally together with a sintering aid, may first be ground alone in the solvent or the solvent mixture for 24 to 72 hours. The sintering aid or sintering aids may also be first ground in the solvent or the solvent mixture and the alumina added to the suspension obtained.
    Type: Grant
    Filed: May 25, 1990
    Date of Patent: February 18, 1992
    Assignee: Hoechst CeramTec Aktiengesellschaft
    Inventors: Carl Hoffmann, Dieter Grote