Patents by Inventor Sixten H. Lejdegard

Sixten H. Lejdegard 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: 4161132
    Abstract: A self-tapping screw, particularly for use in hard materials, such as bricks, concrete and rock, having a screw thread comprising a plurality of circumferentially successive thread portions between which there are voids, wherein at least the front end of each such thread portion is smoothly rounded from the central essentially cylindrical core portion of the screw and rearwardly toward the apex of the screw thread portion.
    Type: Grant
    Filed: December 6, 1977
    Date of Patent: July 17, 1979
    Assignee: Bulten-Kanthal Aktiebolog
    Inventors: Ingvar A. Eklund, Sixten H. Lejdegard
  • Patent number: 4062389
    Abstract: A screw tightening apparatus comprising a motor-driven tool, a screw magazine for screws affixed to a strip-like carrier, and a screw advancing and tightening means for advancing the screws one at a time to a standby position in which a motor-driven bit may engage the screw for applying the same. A bell crank has a spring arm for advancing the screw strip and a drive arm driven by a projection on a plunger against the force of a feed spring to a cocked position, preparatory to advancement of the screw strip, the cocked position being maintained by a pivoted pawl which has a hook that locks the bell crank in such cocked position. A second projection on the plunger member engages the pawl to effect unlocking thereof near the end of a retracting stroke of the plunger member, whereby the feed spring drives the bell crank to advance the strip. A novel means for unlocking a spring-loaded axially slidable lock sleeve is provided.
    Type: Grant
    Filed: February 3, 1976
    Date of Patent: December 13, 1977
    Assignee: Bulten-Kanthal AB
    Inventor: Sixten H. Lejdegard
  • Patent number: 4018334
    Abstract: A fastener package comprising a carrier tape having at equally spaced intervals throughgoing holes in each of which there is received from one side of the tape a screw with a head and a threaded shank, with the under side of the screw head resting against said one side of the tape. The holes are so designed and dimensioned in relation to the dimensions of the screw shanks that, on introduction of the screw shanks into the holes, the tape edges around the holes are deformed into lips which retainingly engage with the screw threads. Radial slots may facilitate the development of the retaining lips, and the slots may be long enough to permit deflection of the lips to let through the screw heads. Adjacent longitudinal slots may be so closely spaced that the tape is split up in two tape portions as the screws are driven home, through the tape.
    Type: Grant
    Filed: March 12, 1976
    Date of Patent: April 19, 1977
    Assignee: Bulten-Kanthal Aktiebolag
    Inventor: Sixten H. Lejdegard
  • Patent number: 4014225
    Abstract: A screw tightening apparatus comprising a motor-driven tool, a screw magazine for screws affixed to a strip-like carrier, and a screw advancing and tightening means for advancing the screws one at a time to a preparatory screw tightening position in which a bit portion of the motor-driven tool may engage with the screw for tightening thereof. The screw advancing and tightening means comprises two axially movable portions, one of which is secured to the tool and the other one of which carries the screw magazine and a spring biased screw advancing mechanism. A push and pull member on the stationary portion is adapted to cooperate with a dog means on the spring biased screw advancing mechanism for advancement of a new screw at the end of the retractive movement of the movable parts into a rest position, subsequent to a completed driving home of a screw.
    Type: Grant
    Filed: March 24, 1975
    Date of Patent: March 29, 1977
    Assignee: Bulten-Kanthal Aktiebolag
    Inventors: Sixten H. Lejdegard, Nils E. Henriksson
  • Patent number: 3969974
    Abstract: The wrenching portion of a nut or a bolt head is provided with a configuration which, when viewed in plan, comprises an outer cylinder having a plurality of grooves defined in part by re-entrant concave surfaces and equiangularly spaced about its periphery, the regions of intersection of the grooves with the outer cylinder being planar. The grooves may be altogether part-cylindrical in cross section, or may they have a part-cylindrical bottom surface which merges with two planar inclined side surfaces.Also disclosed is a matrix or die for use in manufacture of nuts or bolts having a splined wrenching portion, said matrix or die having a die cavity adapted to form the regions of intersection of the grooves with the outer cylinder as planar surfaces.
    Type: Grant
    Filed: February 26, 1974
    Date of Patent: July 20, 1976
    Assignee: Bulten-Kanthal Aktiebolag
    Inventor: Sixten H. Lejdegard