Patents Assigned to Dolmar GmbH
  • Patent number: 9080492
    Abstract: An exhaust system for an internal combustion engine includes an outer housing having a front shell and a rear shell, a prechamber in which exhaust gas from the combustion chamber enters, and an intermediate shell having a front and back as well as a catalytic converter holder. A catalytic converter element is arranged on the catalytic converter holder where an exhaust port directs exhaust gas from the catalytic converter element. To place the center of gravity of the exhaust system near the internal combustion engine or cylinder, the intermediate shell forms the prechamber and the exhaust port.
    Type: Grant
    Filed: August 16, 2011
    Date of Patent: July 14, 2015
    Assignee: DOLMAR GmbH
    Inventor: Christian Kellermann
  • Patent number: 8973721
    Abstract: The invention relates to a braking apparatus, in particular for implements of motor-driven tool units comprising an arm having at least one bearing disposed therein for rotatable mounting of an axle and comprising a flange fastened on the rotatably mounted axle, wherein the axle and/or the flange are drivable by means of a drive motor, wherein a first friction element is firmly connected on the arm and a second friction element is connected to the axle and/or to the flange, wherein the first and the second friction element come into frictional contact with one another or not depending on the action of centrifugal force on at least one flyweight.
    Type: Grant
    Filed: June 3, 2013
    Date of Patent: March 10, 2015
    Assignee: Dolmar GmbH
    Inventors: Mathias Wenckel, Carsten Ziegs
  • Patent number: 8944021
    Abstract: The invention pertains to a device for starting an internal combustion engine for handheld equipment such as chain saws, lawn mowers, lawn trimmers and the like, or for vehicles such as mopeds, boats or miniature aircraft. The starting device features an output element into which a starter torque can be introduced when the starting device is actuated. The output element is functionally connected to a crankshaft of the internal combustion engine in order to introduce a crankshaft torque therein. The functional connection between the output element and the crankshaft introduces variable crankshaft torque into the crankshaft depending on the rotational angle of the crankshaft at a constant starter torque. This advantageously improves force or torque characteristics for largely operating the starter device independently of the compression phase and the expansion phase of the internal combustion engine.
    Type: Grant
    Filed: October 4, 2010
    Date of Patent: February 3, 2015
    Assignee: DOLMAR GmbH
    Inventor: Christian Kellermann
  • Patent number: 8714137
    Abstract: In order to provide a carburettor unit for motorized equipment, in particular hand-operated motorized equipment such as a chain saw, a trimmer, a lawn-cutting appliance, a foliage clearing appliance or suchlike, having a housing , in which a throttle valve and a choke valve are held so as to be movable respectively between a closed position and an open position, which overcomes the disadvantages of the prior art and in which an incorrect position between the throttle valve and the choke valve is avoided, it is proposed that a locking element is provided, which is adjustable through the movement of the throttle valve and cooperates with the choke valve such that a movement of the choke valve into the closed position is locked when the motorized equipment is set in operation.
    Type: Grant
    Filed: November 19, 2009
    Date of Patent: May 6, 2014
    Assignee: DOLMAR GmbH
    Inventors: Manfred Doering, Torsten Haussner
  • Patent number: 8622033
    Abstract: A device is provided for a piece of equipment with an internal combustion engine having a crank case and a combustion space, wherein an air cooling stream is present for cooling the internal combustion engine. The device, on the one hand, is effective for cleaning of the intake air, and on the other hand, a thermal separation between tank and crank case is achieved in a simple manner. The device includes at least one recess, which is constructed open or closed, and is arranged in the crank case, and is separated from an interior of the crank case and forms air cushions.
    Type: Grant
    Filed: March 16, 2009
    Date of Patent: January 7, 2014
    Assignee: DOLMAR GmbH
    Inventor: Carsten Ziegs
  • Patent number: 8534254
    Abstract: In order to create a starter device (100) for an internal combustion engine of a manually guided engine unit, wherein the device comprises a housing (10) and a cable drum (11) which can be rotated relative to the housing (10) about a rotational axis with a starter pull for starting the engine, and has a recoil spring space (14), which is arranged between the housing (10) and the cable drum (11), for a recoil spring (13), in order to move the cable drum (11) into its original position after a rotational movement of the starter, wherein sealing of the recoil spring space (14) is provided, which starter device on the one hand prevents dirt from penetrating into the recoil spring space and on the other hand has a simple design, it is proposed that the seal (15) is spaced apart radially from the rotational axis (X) to such an extent that the recoil spring space (14) is formed by a wall (16) of the cable drum (11) and an approximately opposite wall (17) of the housing (10).
    Type: Grant
    Filed: October 23, 2009
    Date of Patent: September 17, 2013
    Assignee: Dolmar GmbH
    Inventors: Carsten Ziegs, Boris Kaun
  • Patent number: 8499902
    Abstract: The invention relates to a braking apparatus, in particular for implements of motor-driven tool units comprising an arm having at least one bearing disposed therein for rotatable mounting of an axle and comprising a flange fastened on the rotatably mounted axle, wherein the axle and/or the flange are drivable by means of a drive motor, wherein a first friction element is firmly connected on the arm and a second friction element is connected to the axle and/or to the flange, wherein the first and the second friction element come into frictional contact with one another or not depending on the action of centrifugal force on at least one flyweight.
    Type: Grant
    Filed: April 22, 2010
    Date of Patent: August 6, 2013
    Assignee: DOLMAR GmbH
    Inventors: Mathias Wenckel, Carsten Ziegs
  • Patent number: 8424853
    Abstract: In order to provide an actuating device for a choke valve of a carburetor for motorized equipment, in particular a cut-off grinder, wherein the choke valve is movable between at least a closed position and an open position by an operating element via a mechanical coupling from the operating element to the choke valve, which overcomes the disadvantages of the prior art, it is proposed that the mechanical coupling has a separating arrangement which is in operative connection with the motorized equipment such that the mechanical coupling between the operating element and the choke valve can be interrupted or respectively closed as a function of different operating states of the motorized equipment.
    Type: Grant
    Filed: November 19, 2009
    Date of Patent: April 23, 2013
    Assignee: Dolmar GmbH
    Inventors: Mathias Wenckel, Carsten Ziegs
  • Patent number: 8394165
    Abstract: A diaphragm carburettor is connected via a suction port with the clean air side of an air filter. A regulating chamber with a fuel chamber is connected with the suction port, in which the fuel chamber is acted upon with underpressure from the suction port and is separated from a compensation chamber by a regulating diaphragm formed to control the fuel supply to the fuel chamber. The compensation chamber is connected via a compensation path with the clean air side of the air filter and/or with the suction port so that pressure vibrations are reduced in the compensation chamber. A control and/or regulating element associated with the compensation path alters the length and/or the diameter of the compensation path.
    Type: Grant
    Filed: June 30, 2008
    Date of Patent: March 12, 2013
    Assignee: DOLMAR GmbH
    Inventors: Torsten Haussner, Harald Krause
  • Patent number: 8371421
    Abstract: A braking device is provided for braking or immobilizing a shaft in a work tool, particularly a saw chain, hedge shears or the like. The braking device has a brake band that at surrounds at least part of an area of the shaft, in which the brake band forms an effective plane, and two brake band holders with which the brake band may be placed under tension and released, in which at least one brake band holder is constructed movably, and in which a movable brake band holder is arranged with little space requirement in the braking device. At least one brake band holder is mounted outside the effective plane of the brake band so that it is rotatable about the axis of rotation or about an approximately parallel axis or shaft and/or so that it is able to be moved in a linear direction on a plane that is approximately orthogonal with the shaft.
    Type: Grant
    Filed: May 30, 2007
    Date of Patent: February 12, 2013
    Assignee: DOLMAR GmbH
    Inventors: Mark Jesse, Carsten Ziegs
  • Patent number: 8172038
    Abstract: A silencer for a two-stroke engine includes a first chamber and a second chamber, wherein a flow channel is provided between an outlet of a combustion chamber and the first chamber. A high charge degree of the combustion chamber has a pressure ratio in the region of the outlet which reduces or prevents an escape of fresh gas from the combustion chamber. The flow channel between the outlet and the first chamber is flow-favorably shaped in such a manner that the exhaust gas that flows out of the outlet because of its mass inertia predominantly flows into the first chamber and following charging of the first chamber flows back again and as a result a back pressure is formed in the direction of the combustion chamber.
    Type: Grant
    Filed: April 13, 2009
    Date of Patent: May 8, 2012
    Assignee: DOLMAR GmbH
    Inventor: Christian Kellermann
  • Patent number: 8127455
    Abstract: A portable implement is provided that includes a guide rod having a tool element arranged on one end and a motor for driving the tool element arranged on the other end. A holding element for holding the portable implement is arranged between the tool element and the motor. A connecting element is arranged on the guide rod or on the holding element, for connecting the holding element with the guide rod. The connecting element, in a first position of an operating element, is connected with the guide rod displaceably in a longitudinal direction on the guide rod. The connecting element, in a second position of the operating element, is releasably fixed on the guide rod.
    Type: Grant
    Filed: May 7, 2009
    Date of Patent: March 6, 2012
    Assignee: DOLMAR GmbH
    Inventors: Matthias Wenckel, Carsten Ziegs
  • Patent number: 8127743
    Abstract: A work implement in the nature of a drive for a tool includes a starting and/or switching-off braking device for the tool. A brake button is provided which can be externally actuated by a user, with which a starting and/or switching-off brake can be released. A device is also provided which can change the rotational speed of the drive, the device having a throttle button capable of being actuated by the user from outside. The brake button and the throttle button are arranged on a handle so that they can be contacted simultaneously by the hand of a user, where the throttle button can be actuated when the starting and/or switching-off brake is applied.
    Type: Grant
    Filed: November 28, 2005
    Date of Patent: March 6, 2012
    Assignee: DOLMAR GmbH
    Inventors: Christian Vick, Mark Jesse
  • Patent number: 8080075
    Abstract: In order to provide an intake system for sucking in combustion air of an internal combustion engine of a piece of equipment, in particular a portable, manually guided piece of equipment, having more than one centrifugal separator comprising a centrifugal separator housing, and having an air filter device comprising an air filter housing, which bounds an air filter receiving space for an air filter, in which the combustion air can be separated by means of the centrifugal separator into a core volume stream and an outer volume stream, wherein the core volume stream is fed to the internal combustion engine through the air filter receiving space, which intake system is as compact as possible and correspondingly designed to be not very component-intensive, it is proposed for the centrifugal separator housing to be arranged on the air filter housing such that it ends directly at the air filter receiving space or projects directly into the air filter receiving space.
    Type: Grant
    Filed: November 5, 2009
    Date of Patent: December 20, 2011
    Assignee: DOLMAR GmbH
    Inventors: Manfred Doering, Carsten Ziegs, Torsten Luethje, Jan Janzen, Florian Soldat
  • Publication number: 20110296819
    Abstract: An exhaust system for an internal combustion engine includes an outer housing having a front shell and a rear shell, a prechamber in which exhaust gas from the combustion chamber enters, and an intermediate shell having a front and back as well as a catalytic converter holder. A catalytic converter element is arranged on the catalytic converter holder where an exhaust port directs exhaust gas from the catalytic converter element. To place the center of gravity of the exhaust system near the internal combustion engine or cylinder, the intermediate shell forms the prechamber and the exhaust port.
    Type: Application
    Filed: August 16, 2011
    Publication date: December 8, 2011
    Applicant: DOLMAR GmbH
    Inventor: Christian Kellermann
  • Patent number: 8069659
    Abstract: An exhaust system for an internal combustion engine includes an outer housing having a front shell and a rear shell, a prechamber in which exhaust gas from the combustion chamber enters, and an intermediate shell having a front and back as well as a catalytic converter holder. A catalytic converter element is arranged on the catalytic converter holder where an exhaust port directs exhaust gas from the catalytic converter element. To place the center of gravity of the exhaust system near the internal combustion engine or cylinder, the intermediate shell forms the prechamber and the exhaust port.
    Type: Grant
    Filed: August 29, 2007
    Date of Patent: December 6, 2011
    Assignee: Dolmar GmbH
    Inventor: Christian Kellermann
  • Publication number: 20110094468
    Abstract: The invention pertains to a device for starting an internal combustion engine for handheld equipment such as chain saws, lawn mowers, lawn trimmers and the like, or for vehicles such as mopeds, boats or miniature aircraft. The starting device features an output element into which a starter torque can be introduced when the starting device is actuated. The output element is functionally connected to a crankshaft of the internal combustion engine in order to introduce a crankshaft torque therein. The functional connection between the output element and the crankshaft introduces variable crankshaft torque into the crankshaft depending on the rotational angle of the crankshaft at a constant starter torque. This advantageously improves force or torque characteristics for largely operating the starter device independently of the compression phase and the expansion phase of the internal combustion engine.
    Type: Application
    Filed: October 4, 2010
    Publication date: April 28, 2011
    Applicant: DOLMAR GMBH
    Inventor: Christian Kellermann
  • Patent number: 7891099
    Abstract: A damped guiding unit for a portable implement includes a connection element arranged at one end of a guide rod element, for connection of a tool element for the sawing, cutting and/or scything of undergrowth or of grass. A damping element is arranged on the connection element for the damping of oscillations or vibrations caused by the tool element. A holding element is arranged on the guide rod element for holding the portable implement. The holding element and the connection element are structural elements which are respectively separated from each other in that the holding element is associated with a first assembly and the connection element is associated with a further assembly separated from the first assembly. The holding element is further arranged at a distance from the connection element between the one end and the other end of the guide rod element, so that both a direct guiding of the portable implement and also an intensive vibration damping of the holding element is achieved.
    Type: Grant
    Filed: May 7, 2009
    Date of Patent: February 22, 2011
    Assignee: Dolmar GmbH
    Inventor: Matthias Wenckel
  • Publication number: 20100270112
    Abstract: The invention relates to a braking apparatus, in particular for implements of motor-driven tool units comprising an arm having at least one bearing disposed therein for rotatable mounting of an axle and comprising a flange fastened on the rotatably mounted axle, wherein the axle and/or the flange are drivable by means of a drive motor, wherein a first friction element is firmly connected on the arm and a second friction element is connected to the axle and/or to the flange, wherein the first and the second friction element come into frictional contact with one another or not depending on the action of centrifugal force on at least one flyweight.
    Type: Application
    Filed: April 22, 2010
    Publication date: October 28, 2010
    Applicant: DOLMAR GMBH
    Inventors: Mathias Wenckel, Carsten Ziegs
  • Patent number: 7806097
    Abstract: The invention pertains to a device for starting an internal combustion engine for handheld equipment such as chain saws, lawn mowers, lawn trimmers and the like, or for vehicles such as mopeds, boats or miniature aircraft. The starting device features an output element into which a starter torque can be introduced when the starting device is actuated. The output element is functionally connected to a crankshaft of the internal combustion engine in order to introduce a crankshaft torque therein. The functional connection between the output element and the crankshaft introduces variable crankshaft torque into the crankshaft depending on the rotational angle of the crankshaft at a constant starter torque. This advantageously improves force or torque characteristics for largely operating the starter device independently of the compression phase and the expansion phase of the internal combustion engine.
    Type: Grant
    Filed: May 5, 2008
    Date of Patent: October 5, 2010
    Assignee: DOLMAR GmbH
    Inventor: Christian Kellermann