Patents Assigned to Microdot Inc.
  • Patent number: 4478544
    Abstract: The disclosure relates to a reinforced plastic rivet comprising a plurality of substantially continuous carbon fibres encapsulated in a partially polymerized thermoset resin matrix and enveloped in a high tensile strength low modulus tubular sheath. A portion of the rivet is deformable to form a head and fully polymerizable upon heating thereof.
    Type: Grant
    Filed: June 4, 1982
    Date of Patent: October 23, 1984
    Assignee: Microdot Inc.
    Inventor: Norman S. Strand
  • Patent number: 4478543
    Abstract: The disclosure relates to a blind plastic rivet having a fully polymerized head and shear portion and a partially polymerized head forming portion. The head forming portion is deformed upon heating due to tensioning of a centrally disposed mandrel thereby to form a blind rivet having a fully polymerized blind head.
    Type: Grant
    Filed: January 25, 1982
    Date of Patent: October 23, 1984
    Assignee: Microdot Inc.
    Inventor: Lyman R. Lyon
  • Patent number: 4474090
    Abstract: The disclosure relates to a nut installation tool comprising a magazine for storing a plurality of nuts, a rotatable drive spindle having an internal configuration complementary to the external configuration of the nuts so as to slidably accept said nuts yet effect rotation thereof upon rotation of said drive spindle, power driven means for effecting rotation of said drive spindle, and means that function as a stop for said nuts that effects controlled release thereof from said magazine for movement outwardly thereof into said drive spindle.
    Type: Grant
    Filed: May 3, 1982
    Date of Patent: October 2, 1984
    Assignee: Microdot Inc.
    Inventor: Imre Berecz
  • Patent number: 4473728
    Abstract: An electric switch of the push-push type in which a first pushing actuation of a pushbutton assembly moves a switch rocker to a first switching position and a subsequent pushing actuation of the pushbutton plunger assembly moves the switch to an alternate switching position.
    Type: Grant
    Filed: September 9, 1983
    Date of Patent: September 25, 1984
    Assignee: Microdot Inc.
    Inventor: Harry F. Sketch
  • Patent number: 4450614
    Abstract: The disclosure relates to a method of manufacturing an oil seal element from polytetrafluoroethylene and the like. A tubular billet having concentric inner and outer cylindrical surfaces is faced off at one end. An arcuate slit is cut in the end face of the billet at each of a plurality of angularly spaced positions. Indexing of the billet is synchronized with rotation of the slitting tool. A disk of desired thickness having arcuate slits on one of its faces is then sliced from the billet, thereby also facing the billet for the next slitting sequence.
    Type: Grant
    Filed: February 19, 1982
    Date of Patent: May 29, 1984
    Assignee: Microdot Inc.
    Inventor: James A. Repella
  • Patent number: 4451050
    Abstract: A polytetrafluoroethylene seal with intersecting arcuate slitted grooves to effect bi-directional hydrodynamic pumping of oil due to rotation of a shaft about which the seal is disposed.
    Type: Grant
    Filed: May 16, 1983
    Date of Patent: May 29, 1984
    Assignee: Microdot Inc.
    Inventor: James A. Repella
  • Patent number: 4449283
    Abstract: The disclosure relates to a semi-automatic helical insert tool that supports a pair of coils of feed strip having helical inserts thereon. The feed strip is fed through a strip guide to an indexing dial which advances an insert into drive position upon reciprocation of a manually operable trigger on the tool. Actuation of the trigger of the tool not only advances the helical insert into drive position but actuates an air motor to effect advancement of a drive tool into engagement with the insert and drive of the insert into a complementary aperture in a workpiece.
    Type: Grant
    Filed: June 16, 1982
    Date of Patent: May 22, 1984
    Assignee: Microdot Inc.
    Inventors: Imre Berecz, Dennis Schultz, Leroy O. Daniel
  • Patent number: 4432682
    Abstract: In a fastener assembly of the type in which both the internal and external threads have wedge ramp root and crest sections, one of the thread forms is asymmetric so that its following flank has a different flank angle than its leading flank and different from the corresponding following flank of the other thread.
    Type: Grant
    Filed: December 4, 1978
    Date of Patent: February 21, 1984
    Assignee: Microdot Inc.
    Inventor: Arthur J. McKewan
  • Patent number: 4430033
    Abstract: A one-piece sheet metal insert for use in anchorage and fastening applications. The insert is designed to provide sufficient resistance to axial pull-out loading when utilized in relatively soft material workpieces such as structural foam plastic. The insert is also configured to take the clamp load between its collar and internal thread ribs thereby preventing tensile and compressive forces from being applied to the workpiece material surrounding the insert which commonly cause creep to occur.
    Type: Grant
    Filed: April 22, 1981
    Date of Patent: February 7, 1984
    Assignee: Microdot Inc.
    Inventor: Arthur J. McKewan
  • Patent number: 4401469
    Abstract: Cast iron having more regular and uniform free graphite particle shape and distribution is more reliably produced by using pre-reduced iron pellets as a major component of the melting stock. Cast iron made in this way may be advantageously used to form ingot molds, brake discs, and other products.
    Type: Grant
    Filed: March 9, 1981
    Date of Patent: August 30, 1983
    Assignee: Microdot Inc.
    Inventor: John E. Rehder
  • Patent number: 4384181
    Abstract: A small electrical switch assembly for low voltage applications which has an insulating housing and cover, an insulating spring-biased plunger of relatively long travel, two terminals and a grounding terminal, and internal self-wiping contacts; and which is adapted for quick installation and fastening to a grounded structure via an electrically conductive fastening means that automatically grounds the switch assembly if grounding is required; and which is adapted for fully automatic assembly.
    Type: Grant
    Filed: June 25, 1981
    Date of Patent: May 17, 1983
    Assignee: Microdot Inc.
    Inventor: Wayne R. Booden
  • Patent number: 4381163
    Abstract: A prevailing torque type self-locking nut has an internal aperture provided with wedge ramp type threads, the aperture being tapered in cross section adjacent the top of the nut.
    Type: Grant
    Filed: October 6, 1980
    Date of Patent: April 26, 1983
    Assignee: Microdot Inc.
    Inventors: Erwin C. Witte, William D. Myers
  • Patent number: 4375933
    Abstract: A clip nut assembly for use with thin sheet material which includes a generally D-shaped resilient clip having first and second generally parallel clamping portions biased together by an arcuate biasing strip for clampingly engaging opposite faces of a sheet inserted therebetween. A threaded nut is assembled with the second clamping portion for movement therewith. The biasing strip interconnects one end of the first clamping portion with the opposite end of the second clamping portion. This configuration allows the second clamping portion to pivot about two parallel axes and into parallel alignment with the first clamping portion during insertion of the sheet between the clamping portions to automatically align the nut for receivingly engaging a threaded bolt inserted through the sheet. The biasing strip includes an elongated generally diamond shaped aperture which gives the strip a constant strain geometry.
    Type: Grant
    Filed: August 18, 1980
    Date of Patent: March 8, 1983
    Assignee: Microdot Inc.
    Inventors: Donald H. Hassler, Paul V. Pagel
  • Patent number: 4367060
    Abstract: An improved method of manufacturing a sealing nut having a sealing ring insert is disclosed. The process eliminates the costly step of machining an undercut into the counterbore of the nut blank to provide a means for retaining the sealing ring in place. This is accomplished by leaving a predetermined amount of excess material protruding around the periphery of the counterbore when the counterbore is initially cold formed. When the bearing surface is subsequently flattened by an additional cold forming step, the excess material is forced radially inwardly thereby reducing slightly the diameter of the counterbore at the bearing surface of the nut. The elimination of the undercutting operation also results in a nut having improved torque and load bearing characteristics.
    Type: Grant
    Filed: June 2, 1980
    Date of Patent: January 4, 1983
    Assignee: Microdot Inc.
    Inventor: Imre Berecz
  • Patent number: 4352614
    Abstract: A device for effecting a generally tamper resistant threaded connection. The device includes a threaded fastener and a tool for driving and setting the fastener. The fastener has an internally threaded body portion, and a hollow cylindrical axially extending tool engaging portion spaced radially outward from the body portion and interconnected therewith. The tool engaging portion has a generally serrated driving surface defined by a plurality of circumferentially spaced recesses for receiving a like number of complementary shaped projections on the tool. The recesses and the projections cooperate to establish a driving connection between the fastener and the tool when the tool is turned in a direction for driving and setting the fastener. When the tool is turned in a direction for backing-off the fastener once it has been set, the recesses and the projections cooperate to slidingly eject the projections from the recesses to break the driving connection between the tool and the fastener.
    Type: Grant
    Filed: July 23, 1980
    Date of Patent: October 5, 1982
    Assignee: Microdot Inc.
    Inventor: Herbert L. Hirsch
  • Patent number: 4341497
    Abstract: A threaded fastener, such as a bolt, has an externally threaded shank with a standard thread portion along its end portion and a modified thread portion adjacent to it, the modified thread portion having a substantially inclined root section enlarged to interfere with and swage the crest of an internal thread in contact with it and having the leading flank adjacent the inclined root backset to provide space for the swaged crest.
    Type: Grant
    Filed: April 2, 1980
    Date of Patent: July 27, 1982
    Assignee: Microdot Inc.
    Inventors: Gerald P. Downey, Arthur J. McKewan
  • Patent number: 4334814
    Abstract: A threaded fastener particularly suited for use with plastics having spaced apart threads and a negative rake or "hook" formed at the crest of certain of the threads so that axial force applied by the fastener in the direction of the head is translated in part towards the axis of the fastener, thus increasing the failure load of the screw assembly and eliminating premature stripping of the screw threads. Also disclosed is the preferred manner of making the threaded fastener of the present invention.
    Type: Grant
    Filed: July 21, 1980
    Date of Patent: June 15, 1982
    Assignee: Microdot Inc.
    Inventor: Arthur J. McKewan
  • Patent number: 4293258
    Abstract: A self drilling, closed end, blind rivet has a hexagonally shaped flange, or other suitably shaped means of driving, at one end and a hardened drill bit at the other end, with the two being joined by an integral sleeve wall with a rolled groove in it that forms an internal chamber to retain the head of a mandrel. Withdrawal load on the mandrel, after the rivet has been inserted through a hole drilled by it in a plurality of layers to be joined, will upset the sleeve wall into a folded flange that coacts with the hex head, or other driving means, to tightly grip the outside face and the blind face of the layers being joined.
    Type: Grant
    Filed: July 10, 1979
    Date of Patent: October 6, 1981
    Assignee: Microdot Inc.
    Inventor: Arthur J. McKewan
  • Patent number: 4266590
    Abstract: A threaded fastener assembly comprises a bolt with standard 30.degree. flank V-threads and a nut with 30.degree. flank V-threads modified to have wedge ramps between adjacent top and bottom flanks and characterized by the uniform pitch of the nut threads being a predetermined amount less than the uniform pitch of the bolt threads so that there is flank to flank contact between the engaging nut and bolt threads a the top of the nut and the bottom of the nut.
    Type: Grant
    Filed: April 9, 1979
    Date of Patent: May 12, 1981
    Assignee: Microdot Inc.
    Inventor: Arthur J. McKewan
  • Patent number: 4258607
    Abstract: The shank of a self tapping screw has a thread forming section, a threaded section, and a reduced diameter section interconnecting the forming and threaded sections. The thread forming section forms internal threads into a known thread form that has a wedge ramp at its root. The threaded section comprises threads of standard form having the same pitch as the thread forming section. The reduced diameter section is slightly longer than an integer multiple of the pitch so that the threaded section is backset slightly from the forming section.
    Type: Grant
    Filed: September 28, 1979
    Date of Patent: March 31, 1981
    Assignee: Microdot Inc.
    Inventor: Arthur J. McKewan