Patents by Inventor Karl Nitschmann

Karl Nitschmann 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: 6148524
    Abstract: The invention is directed to a low vibration and low noise cutter arrangement for a motor-driven chain saw. The cutter arrangement includes a guide bar and a saw chain. The guide bar has a guide groove for the saw chain which extends along the peripheral edges of the guide bar. The saw chain includes center links and side connecting links which are pivotally connected to each other. The connecting links on the right-hand and left-hand sides of the saw chain include cutting links and side links which are displaced relative to each other. The center links are provided with respective rakers which engage in the guide groove and can be driven in the longitudinal direction of the guide bar by a drive sprocket. The connecting links are supported with slide surfaces on the peripherally extending guide surfaces which lie at both sides of the guide groove.
    Type: Grant
    Filed: October 9, 1998
    Date of Patent: November 21, 2000
    Assignee: Andreas Stihl AG & Co.
    Inventor: Karl Nitschmann
  • Patent number: 6128997
    Abstract: A cutting assembly for a motor chainsaw has a guide bar with peripheral guide groove and guide surfaces. A saw chain circulates in the guide groove in a longitudinal direction of the guide bar. The saw chain has chain members such as centrally arranged drive members and connectors, laterally connecting the drive members. Some of the connectors and some of the drive members are embodied as cutters arranged alternatingly on opposite sides of the saw chain. Rivets connect the chain members pivotably to one another and extend transversely to the circulating direction. The drive members engage the guide groove and the connectors are slidably supported on the guide surfaces. Each cutter has a base, a support stay connected to the base, and a cutting tooth connected to the support stay. The cutting tooth has a laterally projecting roof portion having a leading end in the circulating direction with a roof cutting edge.
    Type: Grant
    Filed: April 23, 1999
    Date of Patent: October 10, 2000
    Assignee: Andreas Stihl AG & Co.
    Inventor: Karl Nitschmann
  • Patent number: 5666733
    Abstract: A guide bar for a saw chain of a motor chainsaw has two side plates having a longitudinal extension. At least one longitudinal stay for fixedly connecting the side plates to one another is provided such that the side plates are positioned substantially congruent and parallel to one another and define a peripheral guide groove therebetween. The longitudinal stay preferably extends in a direction of the longitudinal extension over most of the longitudinal extension of the side plates. The longitudinal stay has contact surfaces and the side plates have support surfaces extending perpendicular to the center plane of the guide bar extending parallel to the side plates. The contact surfaces rest on the support surfaces.
    Type: Grant
    Filed: August 18, 1995
    Date of Patent: September 16, 1997
    Assignee: Andreas Stihl
    Inventor: Karl Nitschmann
  • Patent number: 5257568
    Abstract: The invention is directed to a saw chain for a motor-driven chain saw equipped with a guide bar and a drive motor for imparting a force to the saw chain for moving the latter around the guide bar in a predetermined running direction. The saw chain includes a plurality of side cutting links, a plurality of center driving links and a plurality of side connecting links. The links are pivotally interconnected by rivets to define the saw chain. Entrainers are formed on at least a portion of the connecting links and/or drive links to reliably hold a chip cut by a forward cutting tooth in the free space between two cutting links one directly behind the other. The chip is therefore prevented from slipping relative to the saw chain and is transported out of the kerf without affecting the cutting capacity of the next-rearward cutting link.
    Type: Grant
    Filed: October 29, 1992
    Date of Patent: November 2, 1993
    Assignee: Andreas Stihl
    Inventor: Karl Nitschmann
  • Patent number: 5042350
    Abstract: The invention is directed to a saw chain for a motor-driven chain saw equipped with a guide bar and a drive motor for imparting a force to the saw chain for moving the latter around the guide bar in a predetermined direction. The saw chain includes: a plurality of cutting links, a plurality of driving links and a plurality of connecting links, the links being pivotally interconnected by rivets or the like to define the saw chain. The cutting links have respective cutting teeth disposed at a pregiven elevation above the guide bar. A plurality of non-cutting riders are mounted on selected ones of the links so as to be at an elevation corresponding approximately to the elevation of the cutting teeth for visibly marking the movement of the saw chain around the guide bar.
    Type: Grant
    Filed: September 5, 1989
    Date of Patent: August 27, 1991
    Assignee: Andreas Stihl
    Inventor: Karl Nitschmann
  • Patent number: 4979416
    Abstract: The invention is directed to a cutting link for a saw chain of a motor-driven chain saw. Since the cutting links of the saw chain wear differently at the forward and rearward running surfaces, the cutting link tilts in a direction opposite to the direction of movement of the saw chain whereby a free angle conjointly defined by the roof of the cutting tooth and the cutting plane becomes larger. However, a larger free angle changes the cutting performance of the saw chain. In order to obtain an approximately uniform cutting performance over a longer period of operational use, the tooth roof can be configured over its length to define free angles which become smaller whereby the enlargement of the free angle occurring during the tilting of the cutting link caused by wear is compensated.
    Type: Grant
    Filed: May 16, 1989
    Date of Patent: December 25, 1990
    Assignee: Andreas Stihl
    Inventor: Karl Nitschmann
  • Patent number: 4934052
    Abstract: The invention is directed to a saw chain for a motor-driven chain saw equipped with a guide bar and for which lubricating oil is continuously supplied during operation. The oil reaches the guide groove of the guide bar and is directed to the pivotal joints of the saw chain. The oil is taken up by the foot portions of the center links of the saw chain which engage the guide groove. Groove-like channels are provided in a side face of these foot portions via which the lubricating oil is conducted to the pivotal joints. Lubricant pockets are provided in the foot portions of the center links of the saw chain which are supplementary to the channels so that the center links can take along a greater quantity of lubricant. This lubricant then reaches the pivotal joints through the channels especially at the forward end of the guide bar where the saw chain changes direction.
    Type: Grant
    Filed: December 19, 1988
    Date of Patent: June 19, 1990
    Assignee: Andreas Stihl
    Inventors: Karl Nitschmann, Werner Hartmann
  • Patent number: 4911050
    Abstract: The invention is directed to a saw chain for a motor-driven saw such as a handheld, portable motor-driven chain saw. The motor-driven saw has a guide bar defining a track for accommodating and guiding the saw chain in a predetermined direction of movement. The saw chain includes a plurality of cutting links, a plurality of connecting links and a plurality of driving links, the links being pivotally interconnected by rivets or the like to define the saw chain. Each of the cutting links includes a plate-like body having a base web for defining rearward and forward openings for receiving respective ones of two of the rivets therein. The plate-like body has a rearward portion extending upwardly from the rearward region of the base web to define a cutting tooth. The plate-like body has a forward portion extending upwardly from the forward region of the base web so as to be spaced from the cutting tooth.
    Type: Grant
    Filed: August 12, 1988
    Date of Patent: March 27, 1990
    Assignee: Andreas Stihl
    Inventor: Karl Nitschmann
  • Patent number: 4756221
    Abstract: A saw chain has pivotally interconnected chain links which includes cutting links and safety links and these links are effective as working links. The cutting links are each provided with a cutting tooth for cutting into wood and the safety links are each provided with a projection which limits the depth of the cut of the cutting tooth which follows the safety link. The pivot axes of the chain links lie in an action plane above the guide bar in the stretched portion of the saw chain when the latter is subjected to the pulling force exerted by the drive of the chain saw. The cutting links are pivotable with respect to this plane. In addition, the safety links can also be pivotable in this manner. When the cutting links are in their pivoted-out position under this pulling force, no clearance angle is available at the roof of the cutting tooth so that the cutting edge has no cutting effect. For this reason, there is no kickback when the saw chain is placed against the wood.
    Type: Grant
    Filed: January 28, 1987
    Date of Patent: July 12, 1988
    Assignee: Andreas Stihl
    Inventors: Karl Nitschmann, Hans Dolata, Werner Hartmann
  • Patent number: 4636147
    Abstract: A lubricating-oil pump is disclosed for a motor-driven apparatus such as a chain saw. The lubricating-oil pump delivers lubricating oil to a tool. The supply of lubricating oil from the oil pump to the tool can be interrupted. For example, in this way the flow of oil can be stopped when an accessory tool or the like is mounted on the motor-driven apparatus which requires no lubricating oil during operating.
    Type: Grant
    Filed: August 2, 1985
    Date of Patent: January 13, 1987
    Assignee: Andreas Stihl
    Inventors: Karl Schweitzer, Karl Nitschmann, Hans Dolata
  • Patent number: 4558621
    Abstract: The invention is directed to a saw chain for a motor-driven chain saw which includes cutting links, side connecting links, driving links and safety links. Each safety link has an upper edge defining a wave-like contour that prevents chips from accumulating during the cutting action. The cutting links and safety links of the saw chain are arranged with respect to each other so that overlap is avoided between the tail end of the rearward projection of the safety link and the forward projection of the depth limiter of the cutting tooth. This affords the advantage that cutting chips do not become jammed therebetween.
    Type: Grant
    Filed: July 23, 1984
    Date of Patent: December 17, 1985
    Assignee: Andreas Stihl
    Inventors: Karl Nitschmann, Wilfried Linke, Gunter Dietzsch, Werner Hartmann, Hans-Georg Kaiser, Werner Meyle, Hans Dolata
  • Patent number: 4554853
    Abstract: The invention is directed to a safety arrangement for a saw chain which includes cutting links. A first safety mark is formed in the outside surface of the upwardly-extending portion of the rearmost wall of the cutting link. This first safety mark is disposed at a predetermined distance from the trailing edge of the cutting link and extends in a direction substantially parallel thereto. A second safety mark is formed in the wall of the depth limiter and extends from the leading edge of the cutting link to a notch between the depth limiter and the cutting tooth. The second safety mark is disposed at a predetermined distance below the engaging edge of the limiter.
    Type: Grant
    Filed: October 12, 1983
    Date of Patent: November 26, 1985
    Assignee: Andreas Stihl
    Inventors: Karl Nitschmann, Hans Dolata, Gunter Dietzsch
  • Patent number: 4459890
    Abstract: A saw chain, for power saws, having cutting links alternately on the right-hand and left-hand sides, central driving links, and lateral connecting links. The individual links are pivotally interconnected by means of pins. At least some driving links are provided with a safety projection, which extends in the opposite direction to the direction of rotation. The outer edge of the safety projection is radially farther than the outer edges of the connecting links of the following driving link. As the chain rotates around the free end of the guide rail, in the direction of travel, the rearmost section of the outer edge of the safety projection describes a trajectory which is greater by predetermined amount than the trajectory described by the tip of the cutting tooth.
    Type: Grant
    Filed: November 4, 1982
    Date of Patent: July 17, 1984
    Assignee: Andreas Stihl
    Inventors: Hans Dolata, Werner Meyle, Adam Kelbert, Karl Nitschmann
  • Patent number: 4434556
    Abstract: An arrangement for lubricating saw chains of power saws. The chains include chip removing members, cutting tooth members, connecting links, and other chain members joined by rivet connections. The extensions of the chip removing members run in a guide bar provided with an oil supply. The chip removing members are provided on at least one of their side surfaces with at least one oil guide in the form of a groove in the side surface, which guide extends counter to the running direction of the saw chain and at an incline upwardly toward the rivet connections. The oil guide merges into an oil channel which with at least one of its ends is located in the vicinity or close range of a rivet hole.
    Type: Grant
    Filed: April 16, 1981
    Date of Patent: March 6, 1984
    Assignee: Andreas Stihl
    Inventors: Karl Nitschmann, Gunther Weyda, Bodo Emmrich, Karl O. Stimpfig
  • Patent number: 4409874
    Abstract: A saw chain for chain saws, particularly portable power chain saws, comprising chain members which are pivotally connected with each other. At least some of the chain members are provided with a safety marking to show the extent of wear.
    Type: Grant
    Filed: January 21, 1981
    Date of Patent: October 18, 1983
    Assignee: Andreas Stihl
    Inventors: Karl Nitschmann, Hans Dolata, Gunter Dietzsch
  • Patent number: 4385442
    Abstract: A portable power chain saw with a safety device to protect against kick-back or recoil movements of the saw. The power chain saw has a handle, a finger guard which is arranged between the handle and the saw chain and acts as an inertial mass, as well as a blocking device which actuates the safety device at the beginning of a kick-back movement. The chain saw also includes a monitoring device, which responds to an operating condition of the chain saw impairing the safety of use thereof by an operator, and which is in effective connection with an indicating device. An auxiliary device may additionally be provided for actuating the safety device, and this auxiliary device is releasable by the monitoring device and ultimately brings the saw to a standstill.
    Type: Grant
    Filed: January 28, 1981
    Date of Patent: May 31, 1983
    Assignee: Andreas Stihl
    Inventors: Karl Nitschmann, Gunter Weidmann
  • Patent number: 4296553
    Abstract: A portable power chain saw with at least one grip for carrying the saw which grip is attached by interpositioning of at least one vibration attenuating member and attachment parts to the motor housing of the saw. The grip and the housing are connected to one another with at least one support part associated with said journal being provided.
    Type: Grant
    Filed: November 16, 1979
    Date of Patent: October 27, 1981
    Assignee: Adreas Stihl
    Inventors: Rudolf Dirks, Karl Nitschmann