Patents by Inventor Michael D. Harfst

Michael D. Harfst 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).

  • Publication number: 20140259700
    Abstract: Embodiments herein provide a modified pitch sprocket to provide an orientation of a saw chain link, such as a cutter link or drive link, with respect to the direction of travel of the link, as it traverses the sprocket that is different than the orientation of the link as it traverses a straight portion of the guide bar. In some embodiments, the modified pitch sprocket may orient the cutter link to provide radial extension for a depth gauge of the cutter link relative to a cutting element of the cutter link. This may facilitate shaping of the depth gauge and/or cutting element, such as by a sharpening element, as the cutter link traverses the sprocket.
    Type: Application
    Filed: March 14, 2013
    Publication date: September 18, 2014
    Applicant: BLOUNT, INC.
    Inventors: Mike Goettel, Michael D. Harfst, Christopher D. Seigneur
  • Publication number: 20080011144
    Abstract: Embodiments of the disclosure provide a saw chain having cutter links having a cutting edge on a first end and an opposite second end adapted for riding on or along a rail of a guide bar. First drive links are coupled with the cutter links and are adapted to ride in a groove of a guide bar. The first drive links have a clean out tang sized and shaped to scoop debris from within the groove, and have two first drive link side surfaces on opposite sides thereof adapted to have at least occasional wearing contact with interior side walls of the groove. Second drive links are coupled with the first drive links and the cutter links, and are adapted to ride in the groove of the guide bar. Each second drive link has second drive link side surfaces adapted to have at least occasional wearing contact with the interior side walls of the groove. The second drive link side surfaces have a greater surface area than the first drive link side surfaces, and in some embodiments may be featured rudder links.
    Type: Application
    Filed: July 11, 2007
    Publication date: January 17, 2008
    Applicant: Blount, Inc., a limited liability company of Delaware
    Inventors: Michael D. Harfst, Mark D. Lamey, Mike Goettel, Lewis Scott, Kent Huntington, Mike Patterson, Todd Gerlach
  • Patent number: 6748840
    Abstract: A saw chain for a chain saw including alternating center and side link pairs with certain of said side links being cutting links and certain of said center links preceding said cutting links having guard portions to inhibit kick back. Said guard portions including a forward and rearward guard portion, the rearward guard portion in overlapping relation with a depth guide of the cutting link. A relief spacing between the guard portions facilitates chip carriage and the guard portions cooperatively form a ramp to guide wood being cut over and onto the depth gauge for controlling the depth of cut taken by the cutting link.
    Type: Grant
    Filed: August 7, 2002
    Date of Patent: June 15, 2004
    Assignee: Blount, Inc.
    Inventor: Michael D. Harfst
  • Publication number: 20040025355
    Abstract: A saw chain for a chain saw including alternating center and side link pairs with certain of said side links being cutting links and certain of said center links preceding said cutting links having guard portions to inhibit kick back. Said guard portions including a forward and rearward guard portion, the rearward guard portion in overlapping relation with a depth guide of the cutting link. A relief spacing between the guard portions facilitates chip carriage and the guard portions cooperatively form a ramp to guide wood being cut over and onto the depth gauge for controlling the depth of cut taken by the cutting link.
    Type: Application
    Filed: August 7, 2002
    Publication date: February 12, 2004
    Inventor: Michael D. Harfst
  • Patent number: 6446534
    Abstract: A cutter device has a cutter portion which is led by a depth gauge. The depth gauge is mounted on and extends upwardly from a substantially planar main body section. The depth gauge has a forward, or first section which extends upwardly from the main body, and when viewed from above is disposed at an angle relative to the central plane of the main body diverging therefrom on progressing rearwardly. The rear end of the first section is connected at a juncture section to a second section which progresses rearwardly and is disposed at an angle converging toward the central plane. The second section may extend across the plane of the body and diverge from the opposite side thereof on progressing rearwardly. The upper surface of the depth gauge presents a sweeping curve as viewed from the front of the cutter which is a multiple of the thickness of the body to which it is attached to provide effective cut control for the following cutter.
    Type: Grant
    Filed: April 28, 2000
    Date of Patent: September 10, 2002
    Assignee: Blount, Inc.
    Inventor: Michael D. Harfst
  • Patent number: 6058825
    Abstract: A cutter device has a cutter portion which is led by a depth gauge. The depth gauge is mounted on and extends upwardly from a substantially planar main body section. The depth gauge has a forward, or first section which extends upwardly from the main body, and when viewed from above is disposed at an angle relative to the central plane of the main body diverging therefrom on progressing rearwardly. The rear end of the first section is connected at a juncture section to a second section which progresses rearwardly and is disposed at an angle converging toward the central plane. The second section may extend across the plane of the body and diverge from the opposite side thereof on progressing rearwardly. The upper surface of the depth gauge presents a sweeping curve as viewed from the front of the cutter which is a multiple of the thickness of the body to which it is attached to provide effective cut control for the following cutter.
    Type: Grant
    Filed: March 6, 1997
    Date of Patent: May 9, 2000
    Assignee: Blout, Inc.
    Inventor: Michael D. Harfst
  • Patent number: 5050303
    Abstract: An improved saw bar and a chain sawing assembly includes a frame which houses a drive engine or motor and receives the saw bar, an endless cutting chain, and a sprocket mechanically coupling the drive engine to the cutting chain. The saw bar includes a bar member having a slot formed therein through at least a portion of the thickness of the bar member, with the slot extending from an attachment end to a nose end of the bar member. The saw bar also has a channel assembly, such as a tubular channel assembly, positioned in cooperation with the slot to deliver fluid from the attachment end to a channel outlet. In one embodiment, the saw bar has an idler sprocket pivotally mounted within a sprocket mounting slot formed at the bar member nose end. The channel outlet opens into the sprocket mounting slot to deliver lubrication fluid to the sprocket teeth. In an alternate embodiment, the channel outlet comprises a plurality of apertures along the length of an exposed wall of the channel member.
    Type: Grant
    Filed: December 14, 1990
    Date of Patent: September 24, 1991
    Assignee: Blount, Inc.
    Inventors: James B. Sinclair, Paul W. Pink, Michael D. Harfst, Robin A. Plumbley
  • Patent number: 4873903
    Abstract: Saw chain is assembled with wear links for improving the resistance of saw chain to abrasion from the saw bar. In one embodiment, the wear links are mounted one beside each steel side link in the chain and are constructed to ride along the outer surfaces of the pair of parallel rails upon which the side links also ride as the chain is driven around the bar. The wear links, however, are formed of a material that better resists abrasion than steel but consequently has less tensile strength. To assure that the tensile load on the chain is assumed by the steel side links while the chain is supported on the bar by the wear links, the wear links have oblong pin openings of the same height but of greater length than the circular openings of the side links. In a second embodiment, the wear links are mounted on both sides of each drive link rather than beside each side link.
    Type: Grant
    Filed: July 7, 1988
    Date of Patent: October 17, 1989
    Assignee: Blount, Inc.
    Inventor: Michael D. Harfst
  • Patent number: 4813323
    Abstract: A link for a chain has a first planar portion and a second portion integral with and disposed adjacent the first portion, the second portion being folded over to form a bight having a pair of parallel, laterally-spaced opposed walls defining a space therebetween and adapted to receive a first portion of an adjacent link.
    Type: Grant
    Filed: August 18, 1987
    Date of Patent: March 21, 1989
    Assignee: Blount, Inc.
    Inventor: Michael D. Harfst