Patents by Inventor Damir Cehajic

Damir Cehajic 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: 10493611
    Abstract: The hand-held power tool has a tool holder (2) for holding a tool (4) along a working axis (12). A hammer mechanism (6) has a striker (15) that is moved periodically along the working axis at an impact rate. A drive control (18) of the hammer mechanism (6) sets the impact rate to a set point value. A vibration absorber (19) has an oscillator (21) that moves along the working axis (12) about a resting position and one or multiple springs (20) that drive the oscillator (21) back into the resting position. A calibration phase comprises the following steps: detection of an acceleration using the acceleration sensor (24); determination of a minimum of the acceleration by varying the impact rate in a range of between 90% and 110% of the set point value; and adjusting the set point to the impact rate associated with the ascertained minimum.
    Type: Grant
    Filed: December 1, 2015
    Date of Patent: December 3, 2019
    Assignee: Hilti Aktiengesellschaft
    Inventors: Rainer Ontl, Damir Cehajic, Christoph Dieing
  • Patent number: 9969073
    Abstract: A hand-held power tool is disclosed. The tool has a tool receptacle for holding a chiseling tool. A pneumatic percussion mechanism of the hand-held power tool includes a striker, an exciter and a guide tube. The striker is designed to apply impacts in the impact direction to the tool. The exciter is motor-driven. The striker is coupled by an air spring to the reciprocating movement of the exciter. The striker abutting the guide tube is guided along a working axis. During a movement between an impact position and the exciter, the striker is guided with a constant guide length on the guide tube and if the impact position is exceeded in the impact direction, the guide length is reduced. The hand-held power tool is equipped with an inclined guide, which inclines the striker relative to the working axis when the impact position is exceeded.
    Type: Grant
    Filed: November 12, 2013
    Date of Patent: May 15, 2018
    Assignee: Hilti Aktiengesellschaft
    Inventors: Rainer Ontl, Damir Cehajic, Christoph Dieing, Christian Rehekampff
  • Publication number: 20170361447
    Abstract: The hand-held power tool has a tool holder (2) for holding a tool (4) along a working axis (12). A hammer mechanism (6) has a striker (15) that is moved periodically along the working axis at an impact rate. A drive control (18) of the hammer mechanism (6) sets the impact rate to a set point value. A vibration absorber (19) has an oscillator (21) that moves along the working axis (12) about a resting position and one or multiple springs (20) that drive the oscillator (21) back into the resting position. A calibration phase comprises the following steps: detection of an acceleration using the acceleration sensor (24); determination of a minimum of the acceleration by varying the impact rate in a range of between 90% and 110% of the set point value; and adjusting the set point to the impact rate associated with the ascertained minimum.
    Type: Application
    Filed: December 1, 2015
    Publication date: December 21, 2017
    Inventors: Rainer ONTL, Damir CEHAJIC, Christoph DIEING
  • Patent number: 9789598
    Abstract: A handheld power tool is disclosed. The tool has a housing, a hammer mechanism and a torque coupling. The hammer mechanism includes a beater which is movably guided along the working axis in the guide tube. The guide tube is mounted in a suspension attached to the housing so that it is movable along the working axis. The torque coupling is mounted on the guide tube and is supported on the suspension in the impact direction. The guide tube is supported on the torque coupling in the impact direction. The guide tube may be shifted with respect to the housing in the impact direction such that the torque coupling is shifted relative to the housing through the guide tube in a positively guided manner.
    Type: Grant
    Filed: August 24, 2012
    Date of Patent: October 17, 2017
    Assignee: Hilti Aktiengesellschaft
    Inventors: Rainer Ontl, Christoph Dieing, Christian Rehekampff, Damir Cehajic
  • Publication number: 20150290789
    Abstract: A hand-held power tool is disclosed. The tool has a tool receptacle for holding a chiseling tool. A pneumatic percussion mechanism of the hand-held power tool includes a striker, an exciter and a guide tube. The striker is designed to apply impacts in the impact direction to the tool. The exciter is motor-driven. The striker is coupled by an air spring to the reciprocating movement of the exciter. The striker abutting the guide tube is guided along a working axis. During a movement between an impact position and the exciter, the striker is guided with a constant guide length on the guide tube and if the impact position is exceeded in the impact direction, the guide length is reduced. The hand-held power tool is equipped with an inclined guide, which inclines the striker relative to the working axis when the impact position is exceeded.
    Type: Application
    Filed: November 12, 2013
    Publication date: October 15, 2015
    Applicant: Hilti Aktiengesellschaft
    Inventors: Rainer Ontl, Damir Cehajic, Christoph Dieing, Christian Rehekampff
  • Publication number: 20130220658
    Abstract: A handheld power tool is disclosed. The tool has a housing, a hammer mechanism and a torque coupling. The hammer mechanism includes a beater which is movably guided along the working axis in the guide tube. The guide tube is mounted in a suspension attached to the housing so that it is movable along the working axis. The torque coupling is mounted on the guide tube and is supported on the suspension in the impact direction. The guide tube is supported on the torque coupling in the impact direction. The guide tube may be shifted with respect to the housing in the impact direction such that the torque coupling is shifted relative to the housing through the guide tube in a positively guided manner.
    Type: Application
    Filed: August 24, 2012
    Publication date: August 29, 2013
    Applicant: Hilti Aktiengesellschaft
    Inventors: Rainer Ontl, Christoph Dieing, Christian Rehekampff, Damir Cehajic
  • Publication number: 20110298187
    Abstract: A dust-repelling tool brake is provided for a friction-fitting holding of a tool in the tool brake. The tool brake is provided in the form of an annular cap for deterring dust with an insert opening for an axial mount for the tool. It is provided that an insert ring arranged in the annular cap surrounds an annular section of the annular cap initially limiting the insert opening.
    Type: Application
    Filed: June 2, 2011
    Publication date: December 8, 2011
    Inventors: Rainer Ontl, Christoph Dieing, Christian Rehekampff, Damir Cehajic
  • Patent number: 8051922
    Abstract: A hand-held power tool (1;101) includes a drive (6;110) located in the power tool housing (2;102) for driving a working tool (111), and a torsional pendulum (4; 120; 220; 320; 420; 520) at least partially mounted on the housing (2; 102) for compensating vibrations generated by the drive (6; 110).
    Type: Grant
    Filed: December 16, 2008
    Date of Patent: November 8, 2011
    Assignee: Hilti Aktiengesellschaft
    Inventors: Oliver Ohlendorf, Christoph Dieing, Frank Kohlschmied, Axel Fischer, Damir Cehajic, Rainer Ontl
  • Publication number: 20090218114
    Abstract: A hand-held power tool (1;101) includes a drive (6;110) located in the power tool housing (2;102) for driving a working tool (111), and a torsional pendulum (4; 120; 220; 320; 420; 520) at least partially mounted on the housing (2; 102) for compensating vibrations generated by the drive (6; 110).
    Type: Application
    Filed: December 16, 2008
    Publication date: September 3, 2009
    Inventors: Oliver Ohlendorf, Christoph Dieing, Frank Kohlschmied, Axel Fischer, Damir Cehajic, Rainer Ontl
  • Publication number: 20080047720
    Abstract: A hand-held power tool has a air spring percussion mechanism which is suitable to provide for generating axial impacts by an impact piston reciprocating along an impact axis and which is driven by a crank pin (4) of a rotatably supported eccentric (5) whose mass distribution with respect to an eccentric axis (E) has an unbalance (U) which is offset in the eccentric plane extending perpendicular to the eccentric axis (E) by an angle of unbalance (?) in the range of 70° to 90° relative to the crank pin (4) which is spaced from the eccentric axis (A) by a distance equal to the crank radius (K).
    Type: Application
    Filed: June 7, 2007
    Publication date: February 28, 2008
    Inventors: Reinhard Schulz, Stefan Hammerstingl, Damir Cehajic