Patents Assigned to Sigma Tool & Machine
  • Patent number: 8181712
    Abstract: A nose piece for inserting fixing elements into predefined seats in a work piece includes a drive channel for receiving a lower end of a drive rod. The drive rod is movable from an initial upper position, through a first intermediate position, to a lower position when acted on from above on by a drive force. A lower face of the nose piece is adapted to receive a first fixing element. At least one finger is biased toward a side wall of the nose piece. When the drive rod exerts a force on an actuator, the actuator moves the finger from a closed position, in which a lower portion of the finger is disposed under an outer portion of the flange of the first fixing element, to an open position, in which the lower portion of the finger is disposed away from under the outer portion of the flange of the first fixing element.
    Type: Grant
    Filed: February 20, 2009
    Date of Patent: May 22, 2012
    Assignee: Sigma Tool & Machine
    Inventor: Sung Hsiang Liu
  • Patent number: 7575143
    Abstract: A portable device for inserting fixing elements into predefined seats in a work piece, the portable device including a drive head; a drive rod extending downward from the drive head; a hollow nose piece slidably fit around a lower end of the drive rod, the nose piece being attached to the head and being movable vertically by a predetermined distance with respect to the head and the drive rod; a magazine mounted on the nose piece at a predetermined angle with respect to a lower face of the nose piece for feeding a first fixing element into a horizontal slot on the lower face the nose piece; and a single-blow drive mechanism providing a force produced by a pressurized fluid to an upper end of the drive rod when the drive mechanism is triggered. The force on the drive rod drives the first fixing element into the predefined seat in the work piece.
    Type: Grant
    Filed: September 13, 2007
    Date of Patent: August 18, 2009
    Assignee: Sigma Tool & Machine, A Partnership Between Sigma Tool & Machine Ltd. And Sigma Fasteners, Ltd.
    Inventors: Keith G. Bromley, Sung Hsiang Liu
  • Patent number: 7571844
    Abstract: A portable device for inserting fixing elements into predefined seats in a work piece, the portable device including a drive head; a drive rod extending downward from the drive head; a hollow nose piece slidably fit around a lower end of the drive rod, the nose piece being attached to the head and being movable vertically by a predetermined distance with respect to the head and the drive rod; a magazine mounted on the nose piece at a predetermined angle with respect to a lower face of the nose piece for feeding a first fixing element into a horizontal slot on the lower face the nose piece; and a single-blow drive mechanism providing a force produced by a pressurized fluid to an upper end of the drive rod when the drive mechanism is triggered. The force on the drive rod drives the first fixing element into the predefined seat in the work piece.
    Type: Grant
    Filed: January 26, 2006
    Date of Patent: August 11, 2009
    Assignee: Sigma Tool & Machine, a Partnership between Sigma Tool & Machine Ltd. and Sigma Fasteners, Ltd.
    Inventors: Keith G. Bromley, Sung Hsiang Liu
  • Patent number: 6317970
    Abstract: A clip crimping tool includes a body provided with a hollow air storage area and a drive section provided with piston cylinder and a piston, and having a main valve with a diameter that is larger than the piston cylinder and is arranged with the drive section is in line or at an angle with a contact section in which clips are crimped. The air storage area and the arrangement of the main valve and piston cylinder allow the free flow of compressed air into the piston cylinder to provide a fast and efficient drive action.
    Type: Grant
    Filed: April 28, 2000
    Date of Patent: November 20, 2001
    Assignee: Sigma Tool & Machine
    Inventors: Herbert E. Leistner, Carlo Stagnoli
  • Patent number: 6305888
    Abstract: A T-Nut having a generally tubular barrel with an interior female thread and a flange with prongs bent to embed in a work piece, and in which the flange has planar sides to ride in a feed guide, and has end edges on the flange, at the leading and trailing edges of the flange, which end edges can contact respective end edges on leading and trailing T-Nuts within the feed, a generally median U-shaped depression formed in each of the leading and trailing edges and, generally arcuate recesses formed in each of the edge flange, on either side of the U-shaped depression.
    Type: Grant
    Filed: June 7, 2000
    Date of Patent: October 23, 2001
    Assignee: Sigma Tool & Machine
    Inventor: Herbert E. Leistner
  • Patent number: 6209722
    Abstract: A fastener strip with a grip portion, and flanges formed around the grip portion, and a membrane or membranes formed of flexible material, adhesive bonding a membrane to first sides of the flanges, with the fastener in sequential relation along the membrane and portions of a membrane bonded to second sides of the flanges, so that the membrane portions grip the flanges on both first and second side surfaces simultaneously.
    Type: Grant
    Filed: April 30, 1999
    Date of Patent: April 3, 2001
    Assignees: Sigma Tool & Machine, A Partnership of Sigma Tool & Machine Ltd., Sigma Fasteners Ltd.
    Inventor: Martin Leistner
  • Patent number: 6183181
    Abstract: A Tee-nut fastener device having a tubular threaded sleeve and a flange around one end of the sleeve and a through bore extending from one end of the sleeve to the other, and a closure sealing the flange end of the sleeve while leaving the opposite end of the sleeve open.
    Type: Grant
    Filed: October 27, 1999
    Date of Patent: February 6, 2001
    Assignee: Sigma Tool & Machine
    Inventors: Herbert E. Leistner, Carlo Stagnoli
  • Patent number: 6129493
    Abstract: A Tee-nut having a flange head, a plurality of prongs extending from the flange head, and a hollow sleeve extending from the flange head. The hollow sleeve has an internally threaded reduced diameter waist portion connecting to the flange head, and an enlarged globular bulbous portion extending from the internally threaded waist portion. The end of the enlarged bulbous portion is radiussed inwardly to facilitate insertion into a hole in a workpiece. Also disclosed is a workpiece fitted with such a Tee-nut.
    Type: Grant
    Filed: October 26, 1999
    Date of Patent: October 10, 2000
    Assignee: Sigma Tool & Machine
    Inventors: Herbert E. Leistner, Paul D. Green, Richard J. Pfeiffer
  • Patent number: 5918738
    Abstract: A Tee-nut strip having Tee-nuts with generally cylindrical internally threaded sleeves, and flanges formed around one end of the sleeves, and a membrane or membranes formed of flexible material, adhesive bonding a membrane to first sides of the flanges, with the Tee-nuts in sequential closely spaced relation along the membrane and, portions of a membrane bonded to second sides of the flanges, so that the membranes portions grip the flanges on both first and second side surfaces simultaneously, and a method of forming a Tee-nut strip with upper and under membranes gripping the flanges on both sides.
    Type: Grant
    Filed: November 12, 1998
    Date of Patent: July 6, 1999
    Assignee: Sigma Tool & Machine
    Inventor: Martin Leistner
  • Patent number: 5909993
    Abstract: A nail having a shank formed with at least one shallow chipped recess, so as to provide nail recesses of a precise predetermined depth, and a strip of such recessed nails, in which wires are welded to the nails in respective chipped recesses. Two or more such recesses may be formed in each nail.The nails may either be arranged in a diagonally staggered fashion with their heads overlapping, or may be spaced further apart so that they are parallel, with their heads aligned, but in which the heads do not overlap.Also disclosed is apparatus for forming a strip of nails having recesses, and having at least two spaced apart rotary chipping tools, operable to form spaced apart recesses in the nails, at least two wire welding stations aligned with the recesses in the nails and strip wire supplies, and welders to weld the strip wires in the recesses forming the nails into a strip, and a method of forming a wire welded strip of recessed nails.
    Type: Grant
    Filed: November 12, 1997
    Date of Patent: June 8, 1999
    Assignee: Sigma Tool & Machine
    Inventor: Walter H. Leistner
  • Patent number: 5863164
    Abstract: A Tee-nut with flareable portion comprises a flange head, a plurality of prongs extending from the flange head, and a hollow barrel extending from the flange head. The hollow barrel has an internally threaded portion provided at one end of the barrel connecting to the flange head, and an enlarged flareable portion extending from the internally threaded portion and provided at a free end of the barrel. The end of the enlarged flareable portion is radiussed inwardly so as to form an end opening having a diameter which reduced in relation to the diameter of the flareable portion to facilitate insertion into a hole in a workpiece. The present invention further discloses a workpiece fitted with such a Tee-nut.
    Type: Grant
    Filed: January 23, 1998
    Date of Patent: January 26, 1999
    Assignee: Sigma Tool & Machine
    Inventor: Volkmar W. Leistner
  • Patent number: 5762190
    Abstract: A tee-nut holder strip of breakable material, and a plurality of tee-nuts having threaded sleeves and flanges, and spikes formed from portions of the flanges and having a strip defining a plurality of precisely spaced apart holes formed axially along the central axis of the strip for receiving the sleeves of the tee-nuts, the holes being undersized relative to the sleeves and displacement of material by the sleeves causing a wedging grip on the sleeves and, strip material located around the holes and the tee-nuts having their spikes penetrating through the material around the holes, thereby holding the tee-nuts in a predetermined precisely spaced apart relationship in the strip of material, the material being breakable between the tee-nuts, to permit punching in of individual tee-nuts one at a time, into a workpiece.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: June 9, 1998
    Assignee: Sigma Tool & Machine
    Inventor: Martin Leistner
  • Patent number: 5722131
    Abstract: A furniture clip of the type used with furniture springs, having wire frames, and in which such furniture clips furniture clips are used for attaching the wire frames to furniture, and having a sheet metal member defining length and width, and formed transversely with a wire receiving recess, and two panels extending at an acute angle relative to one another on either side of the recess, a shield of flexible thermoplastic material extending over the inner surfaces of the two panels, and extending around said wire recess, and edge portions of the thermoplastic defining a width greater than the width of the sheet metal.
    Type: Grant
    Filed: July 25, 1995
    Date of Patent: March 3, 1998
    Assignee: Sigma Tool & Machine
    Inventors: Volkmar W. Leistner, Garry Randall Olson
  • Patent number: 5618144
    Abstract: A tee-nut comprises a flange head, a plurality of prongs extending from the flange head, and a hollow barrel extending from the flange head. The hollow barrel has an internally threaded portion provided at one end of the barrel connecting to the flange head, and an enlarged flarable portion extending from the internally threaded portion and provided at a free end of the barrel. The present invention further discloses a method of forming a tee-nut with an enlarged barrel end, by first swaging out and expanding the free end of the barrel and thereafter threading the unexpanded portion of the barrel.
    Type: Grant
    Filed: September 11, 1995
    Date of Patent: April 8, 1997
    Assignee: Sigma Tool & Machine
    Inventor: Volkmar W. Leistner
  • Patent number: 5606794
    Abstract: A machine for inserting a Tee-nut into a workpiece of the type having a Tee-nut supplying source and a power cylinder assembly, the power cylinder assembly comprising a cylinder having an upper end headplate and a lower end headplate, openings provided on the cylinder for admitting and venting compressed air, a piston moveable within the cylinder, a piston rod secured to the piston, the lower end of the piston rod extending through the lower end headplate and adapted to engage and drive a Tee-nut into a workpiece, the upper end of the piston rod extending through the upper end headplate, and a kinetic energy storage unit removably mounted to the upper end of the piston rod, thereby providing a mass on the piston which is accelerated by gravity and air pressure during a downward stroke and is sufficient to drive a Tee-nut into a workpiece with a very low shock effect and to a precise depth.
    Type: Grant
    Filed: July 6, 1995
    Date of Patent: March 4, 1997
    Assignee: Sigma Tool & Machine
    Inventor: Volkmar W. Leistner
  • Patent number: 5560099
    Abstract: A machine for setting and forming a Tee-nut, of the type having a threaded sleeve and an open lower end on the sleeve, in a workpiece, and having a cylindrical body having an upper opening and a stop, a pin member slidably received within the body and having a top end die portion defining a forming surface, a first resilient device for urging the pin member in an upper normal position, and a second resilient device disposed concentrically around the pin member.
    Type: Grant
    Filed: July 20, 1994
    Date of Patent: October 1, 1996
    Assignee: Sigma Tool & Machine
    Inventors: Walter H. Leistner, Volkmar W. Leistner
  • Patent number: 5501558
    Abstract: An anti-friction Tee-nut for use in Tee-nut setting machines having a feed mechanism, and the Tee-nut having a threaded sleeve portion, a flange portion substantially normal to the threaded sleeve portion around one end thereof, the flange portion defining upper and lower surface planes, and the flange portion being adapted to be received in the feed mechanism of a setting machine, and, deflected portions deflected out of the upper surface plane of the flange portion along the leading and trailing end edges of the flange.
    Type: Grant
    Filed: August 25, 1994
    Date of Patent: March 26, 1996
    Assignee: Sigma Tool & Machine
    Inventors: Siegfried Figge, Martin K. Leistner
  • Patent number: 5478002
    Abstract: A magnetic Tee-nut holder for use in a Tee-nut setting machine having a f guide channel for feeding and guiding Tee-nuts towards the end of the channel in registration with a rod for driving the endmost Tee-nut into a workpiece. The magnetic Tee-nut holder is positioned at the end of the channel for magnetically holding the endmost Tee-nut in a position in registration with the driving rod. Also disclosed is a method of magnetically holding a Tee-nut at the end of a feed guide channel of a Tee-nut setting machine, for driving by a driving rod.
    Type: Grant
    Filed: June 17, 1994
    Date of Patent: December 26, 1995
    Assignees: Sigma Tool & Machine, Partnership of Sigma Tool & Machine Ltd., Sigma Fasteners Ltd.
    Inventors: Ole Clement, Ivan J. Leko
  • Patent number: 4711980
    Abstract: Apparatus for forming nails into a nailing strip, in which nails are welded to wire strips, and having a nail feed, a nail indexing wheel indexing nails into predetermined nail spacings, a nail rotator to bring their heads in a predetermined orientation, a nail handling slide for receiving nails, a wire feed for feeding wire to one side of the nails, electrical welding contacts for pressing the wire against nail and passing a welding current to weld the wire to the nail, a moving device for moving the welding contacts towards and away from the nails, and a movement device for moving the nails along the nail slide.
    Type: Grant
    Filed: February 18, 1986
    Date of Patent: December 8, 1987
    Assignee: Sigma Tool & Machine Limited
    Inventor: Walter H. Leistner
  • Patent number: 4508478
    Abstract: A fastener member having a base flange, a central perpendicular sleeve with internal threads for reception of a threaded fastening, fastening teeth struckout of such base flange for reception in a wooden work piece, the base flange having a forward feed edge and a rearward feed edge, and side feed edges, and abutment means in the base flange adjacent the feed edges and spaced apart from the fastening teeth, adapted to inter-engage with one another to prevent such feed edges from overriding one another in a feed track.
    Type: Grant
    Filed: July 11, 1983
    Date of Patent: April 2, 1985
    Assignee: Sigma Tool & Machine Limited
    Inventor: Herbert E. Leistner