Forming Thread Patents (Class 470/10)
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Patent number: 7195438Abstract: A fastening system is provided that includes a fastener having a pin member with a lock groove and crest geometry that is optimized to receive swaged material from collars of materials of different strengths for securing workpieces for different load applications. The lock grooves have the longest width required for collars of lower strength for one application or greater strength for a second application and the crests have the longest width required for collars of greater strength for the second application whereby satisfactory clamp and tensile loads and resistance to failure will result when the lock grooves are filled with collar materials of different strengths. Certain collars of different materials have similar outside diameters for installation by a tool having a swage anvil with a uniform swage cavity that swages the collars into the lock grooves for securing workpieces in shear, shear/tension, shear composite and shear/tension composite applications.Type: GrantFiled: January 5, 2004Date of Patent: March 27, 2007Assignee: Huck International, Inc.Inventors: Thomas E. Harbin, Hai-Tao Wang, Michael U. March
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Patent number: 7189251Abstract: The invention relates to a tissue anchor which is an open helix of biocompatible material having a slope of from 0.5 to 10 turns per centimeter, a length from 3 to 75 millimeters, a diameter of from 1.5 to 11 millimeters, and an aspect ratio of from about 3 to about 5 to 1. The anchor can have a head which is capable of securing or clamping tissue together, such as holding a suture to secure a ligament or tendon to bone. The anchor can also have a head which causes an inward, compressive loading for use in fastening bone to bone, orthopedic plates to bone, or cartilage to bone. The head may be an integral member and may include a self-reinforcing wedge which joins the helix to the head. Further, the elongate member, or filament that forms the helix may have a tapering diameter along its length.Type: GrantFiled: May 28, 2003Date of Patent: March 13, 2007Assignee: Orthohelix Surgical Designs, Inc.Inventor: David B. Kay
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Patent number: 7159429Abstract: A method and apparatus for manufacturing a bolt capable of mass-producing a multiple screw bolt such as a so-called double screw bolt at a low unit price, and a thread rolling die for use therein. The apparatus for manufacturing a bolt comprises a pair of thread rolling dies (1) which are arranged opposite to each other at a predetermined interval, and a bolt supporting unit (2) which supports a cylindrical bolt material (3) in a predetermined position. The thread rolling dies (1) are provided with a transfer pattern (4) having a coarse thread portion (5) which is part of a coarse thread formed by developing a coarse screw, and projections (6) which are part of a fine thread (6a) formed by developing a fine screw as shown by an imaginary line (6a), the fine thread (6a) being formed cyclically on a root portion (5a) of the coarse thread according to a phase shift between the fine thread and the coarse thread.Type: GrantFiled: March 19, 2004Date of Patent: January 9, 2007Assignee: Kyushu TLO Company, LimitedInventors: Teruie Takemasu, Hiroshi Miyahara
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Patent number: 7156600Abstract: A threaded fastener comprises a first, primary thread lead, and a pair of second, auxiliary thread leads alternatively interposed between successive threads of the first, primary thread lead, except within the vicinity of the tip portion of the fastener so as to define space for accommodating debris generated during the self-tapping of the fastener into a workpiece. The fastener also comprises lobe members formed upon the primary thread lead so as to predeterminedly affect torque insertion and pull-out resistance values.Type: GrantFiled: May 13, 2004Date of Patent: January 2, 2007Assignee: Illinois Tool Works Inc.Inventors: Cheryl L. Panasik, Kenneth R. LeVey, Robert B. Fischer
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Patent number: 7051875Abstract: A curved screwstrip comprising in combination a plastic holding strap and a plurality of threaded fasteners. The plastic holding strap has a greater mass in its top half than in its bottom half so that shrinking after extrusion will tend to have the holding strap adopt a preferred curved configuration.Type: GrantFiled: December 17, 2003Date of Patent: May 30, 2006Assignee: Simpson Strong-Tie Company, Inc.Inventors: G. Lyle Habermehl, Troy D. Hale, William S. Kepley
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Patent number: 6984235Abstract: A method of fusing a joint between two bones, comprising boring a hole through one of the bones across the joint therebetween and into the other bone, placing the leading end of a screw into the hole, where the screw has a threaded region having a pitch that is larger toward a leading end of the screw and smaller toward a trailing end of the screw, and driving the screw into the bone until the threaded region spans the joint.Type: GrantFiled: June 3, 2002Date of Patent: January 10, 2006Assignee: Acumed LLCInventor: Randall J. Huebner
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Patent number: 6957557Abstract: A new and improved thread rolling die for forming a new and improved threaded fastener, and a new and improved method or technique of manufacturing the new and improved threaded fastener, is disclosed wherein the new and improved threaded fastener comprises a first, primary thread lead, and a pair of second, auxiliary thread leads alternatively interposed between successive threads of the first, primary thread lead. As a result of the provision of the pair of second, auxiliary thread leads being interposed between successive ones of the threads of the first, primary thread lead, not only is additional axial reinforcement provided for the threaded fastener, but more importantly, the lateral or transverse distance through which the material comprising the blank member must be displaced or moved in order to form the successive threads of the first, primary thread lead is substantially reduced.Type: GrantFiled: January 31, 2005Date of Patent: October 25, 2005Assignee: Illinois Tool Works Inc.Inventor: Kenneth R. LeVey
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Patent number: 6886384Abstract: A process for the formation of a thread form in a substantially elongate member (1), wherein the thread form includes at least one rib (3) spaced apart from at least one other rib along the elongate member and wherein the thread form has a relatively coarse rib spacing but a fine thread pitch.Type: GrantFiled: March 15, 2001Date of Patent: May 3, 2005Inventor: Peter Andrew Gray
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Patent number: 6878069Abstract: Helical groove fasteners and methods for producing the same are provided for use in systems requiring fluid passage through the fastener. In one embodiment, the fastener includes a shank, a head, a threaded portion, and at least one groove extending through at least a portion of the threaded portion. The fastener can include a single groove or multiple grooves. In certain preferred embodiments, the helix rotation angle of the groove is selected so that the shank has a continuous diameter to facilitate the thread forming process. In preferred embodiments, the fastener is cold forged and the threads are formed using a thread rolling die.Type: GrantFiled: June 5, 2003Date of Patent: April 12, 2005Assignee: SPS Technologies, Inc.Inventor: Ollie C. Swim, Jr.
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Patent number: 6780115Abstract: The length of a bone fracture fixation screw may be intraoperatively adjusted with the aid of a cutting jig that includes a measuring block which is slidable along a rail adjacent a measuring scale and a holding block to facilitate cutting the distal end of the screw once the desired length has been determined. A tip sharpener may be incorporated into the cutting jig or may be provided separately, for reforming a point at the distal tip of the cut fixation screw.Type: GrantFiled: June 7, 2002Date of Patent: August 24, 2004Assignee: Arthrex, Inc.Inventors: Reinhold Schmieding, Karen L. Gallen
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Publication number: 20040127297Abstract: The novel concept to be patented involves minutely indenting the standard fasteners along the pitch line at various points and utilizing the small material deformations around these indentations to provide substantial engagement to resist loosening of the joint under operational loads. The basic idea is to stamp a typical pattern (two are described below) on the fastener to achieve the advantages of a self-locking mechanism as well as enhance the torque and load carrying capability of the joint. Moreover, the indentations being in the order of few mils would not degrade the strength of the fastener, but would continue to provide sufficient load transfer across the joint without loss of preload. Furthermore, the joint can be disassembled and the fasteners can then be reused for the subsequent operations. These unique indentations on the fasteners can be of varying numbers, depths, geometry (spherical, elliptical etc.) and of various patterns (linear, staggered etc.Type: ApplicationFiled: December 30, 2002Publication date: July 1, 2004Inventors: Barun Majumdar, Arunabh Bhattacharya
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Patent number: 6712708Abstract: A headed multi-lobed blank, method of manufacturing a self-tapping screw from the blank, and resulting multi-lobed self-tapping screw for joining thin workpieces provides desirable thread-forming characteristics at the conical tip and body portions, and improved resistance to vibrational loosening near the head. The resulting screw, obtained from the blank and method, incorporates a threaded tapered root portion between the screw head and body portion having a cross section that varies from nearly circular in the area adjacent to the underside of the head to a maximum out-of-round (or lobular) cross section at the intersection of the tapered root portion and the screw body.Type: GrantFiled: October 3, 2002Date of Patent: March 30, 2004Assignee: Conti Fasteners AGInventors: Dennis O. Boyer, Alan Pritchard
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Patent number: 6708544Abstract: In a rolling die for forming a ball screw by rolling for example, a biting portion is formed on one end of a straight portion while a relief portion is formed on the other end. Further, the helical protrusion on the biting portion and the helical protrusion on the relief portion each become continuously and gradually smaller as distancing away from the dancette portion on the straight portion. The dancette portion on the various portions are continuously formed using only one grinding wheel with its grinding lead being changed.Type: GrantFiled: February 15, 2002Date of Patent: March 23, 2004Assignee: NSK Ltd.Inventor: Hitoshi Sannomiya
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Patent number: 6702684Abstract: A fastening system is provided that includes a fastener having a pin member with a lock groove and crest geometry that is optimized to receive swaged material from collars of materials of different strengths for securing workpieces for different load applications. The lock grooves have the longest width required for collars of lower strength for one application or greater strength for a second application and the crests have the longest width required for collars of greater strength for the second application whereby satisfactory clamp and tensile loads and resistance to failure will result when the lock grooves are filled with collar materials of different strengths. The lock groove and crest geometry is of a uniform construction for the plurality of applications with pin members of a common diameter.Type: GrantFiled: June 28, 2002Date of Patent: March 9, 2004Assignee: Huck International, Inc.Inventors: Thomas E. Harbin, Hai-Tao Wang, Michael U. March
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Patent number: 6551323Abstract: A screw for use in spinal and other surgical procedures has a tapered core and fixed pitch threads. The threads have a compound curved inferior surface and constant width crest. The screw may be provided with a helical thread in which at least the lead thread adjacent to the screw tip is ledged and the following threads have sharp apices. A method of making the screw requires two tool bits making two different angular cuts to the inferior surface of the threads.Type: GrantFiled: July 26, 2001Date of Patent: April 22, 2003Assignee: Hammill ManufacturingInventors: Robert L. Doubler, John E. Hammill, Sr., Jeffrey Lasner
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Patent number: 6540619Abstract: The object of the present invention is to prevent the encroaching and the seizure between the bolt and the female screw caused by an oblique screwing of the bolt into the female screw when the bolt and the female screw are fastened together. Another object of the present invention is to manufacture the bolt in a low cost, by using said bolt, the encroaching and the seizure between the bolt and the female screw caused by a oblique screwing of the bolt into the female screw are certainly prevented. Said objects may be attained by a bolt consisting of a column part and a polygonal pillar part extending from an end of said column part wherein a complete thread is formed on said column part and a screw blade continuing to said complete thread is formed on said polygonal pillar part.Type: GrantFiled: December 11, 2001Date of Patent: April 1, 2003Assignee: Meidoh Co., Ltd.Inventor: Takashi Kato
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Patent number: 6446520Abstract: A ball screw 2 or a sliding screw 2a has a driving force-transmitting shaft 4 or 4a and a bearing member 6 or 6a externally fitted to the driving force-transmitting shaft 4 or 4a. The driving force-transmitting shaft 4 or 4a is made of aluminum or aluminum alloy, and the bearing member 6 or 6a is made of any one of synthetic resin, aluminum, and aluminum alloy. The member, which is formed by using the aluminum or the aluminum alloy, is applied with a surface treatment, and preferably, it is further applied with a surface finish treatment.Type: GrantFiled: July 7, 2000Date of Patent: September 10, 2002Assignee: SMC Kabushiki KaishaInventors: Shigekazu Nagai, Hiroyuki Shiomi
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Patent number: 6440001Abstract: Apparatus and method for forming a pin and nut fastener assembly for temporarily or permanently securing two panels having conventional drilled generally aligned holes into which the assembly is inserted. Weight of the pin and nut is reduced while retaining predetermined industry established strength requirements. The thread section of the pin is reduced along with the mating thread of the nut. The pin may be cold-worked in critical areas.Type: GrantFiled: June 7, 2001Date of Patent: August 27, 2002Assignee: Avibank Mfg., Inc.Inventors: John A. Duran, Edward Avetisian, Todd Diamond
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Patent number: 6371709Abstract: A screw thread having a threadform including a ridge rising from root to crest with the crest having two peaks, separated by a trough the depth of which is less than the height of the ridge from root to crest. It has particular use as a screw for timber, and is especially suited to fixing railway rails to sleepers.Type: GrantFiled: October 27, 2000Date of Patent: April 16, 2002Assignees: Hanstock Fasteners Pty Limited, Reid Construction Systems Pty LimitedInventors: Fotios Papafotiou, David Ian Kershaw
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Patent number: 6328657Abstract: A threaded fastener lighter in weight and easier to produce is made by the moderate temperature-forging, from a raw magnesium material that contains microcrystals whose diameter is about 100 &mgr;m or less. The raw material may be pure magnesium of industrial grade in one case, and alternatively be any magnesium alloy or such a composition as comprising as its matrix the alloy or pure magnesium, in the other cases. The raw material has a superplastic property and a fine-granulated metallographic internal texture, and when making the fastener, will be heated to 250-400° C. at which superplasticity takes place to facilitate the forging to form the fastener. A method proposed in the invention to make the fastener is thus such that the number of necessary processing steps is reduced and manufacture cost is lowered.Type: GrantFiled: March 27, 2000Date of Patent: December 11, 2001Assignees: Kurimoto, Ltd., Kishiwada Stainless Steel Works, Kenji HigashiInventors: Masayoshi Kitagawa, Yoshisada Michiura, Keiichi Maekawa, Mitsuaki Kohara, Kenji Higashi, Takeyuki Asaoka
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Patent number: 6216510Abstract: A self-lock screw which has a deep slit so as to facilitate the elastic deformation of the flanks of a thread and enhance the locking effect and which can be produced without the need for skill of a high level and dexterity. A slit (3) which separates the flanks (21) on both sides of a thread (2) along the crest of the thread is provided, and a broad bottomed concave portion (22, 23) is formed from the vicinity of the root of the thread (2) in a shape given by inwardly scraping the extended surfaces of the flanks. Since the slit at the crest of the thread becomes deep by providing the broad bottomed concave portion in the vicinity of the root of the thread, the flanks are ready to be elastically deformed, so that the spring back effect is enhanced and the effect on preventing the screw from loosening is therefore increased.Type: GrantFiled: March 31, 1999Date of Patent: April 17, 2001Assignee: The Holistic Environment Creators Co., Ltd.Inventor: Hideo Hashimoto
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Patent number: 6213884Abstract: A method for heat treating a metal article such as a fastener comprising the step of case hardening the fastener in a gas carborizing atmosphere at a temperature of about 1700° F. or in a carbonitriding atmosphere at a temperature of about 1550° F., and quenching the fastener in water or oil and tempering the fastener at a minimum temperature of 770° F. for approximately one hour.Type: GrantFiled: October 20, 1999Date of Patent: April 10, 2001Assignee: DaimlerChrysler CorporationInventor: Eric McCarty
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Patent number: 6206620Abstract: A pivoting split thread chasing die for rethreading and cleaning damaged or inhibited studs or bolts; and a method of manufacturing the die. The identical main body halves of the pivoting split die, when assembled together with an assembly pin form a pivoting split die with opposing front and rear faces and a hexagonal outside periphery. Threads are formed on the inside periphery of the pivoting split die allowing for engagement with the threads of a stud or bolt. One or more material reliefs are formed on the inside periphery of the pivoting split die to enhance the cleaning and rethreading ability of the pivoting split die threads. These reliefs also serve as points for which debris can escape while performing a rethreading procedure. To rethread or clean a damaged or inhibited bolt or stud, apply an appropriate lubricant to the area to be rethreaded or cleaned.Type: GrantFiled: April 22, 1999Date of Patent: March 27, 2001Inventor: Brian D. Burns
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Patent number: 6149363Abstract: The present invention is to a lightweight threaded bolt type fastener having a shank with a large diameter portion and small diameter portion connected by a transition portion; a thread is roll formed on the small diameter portion and terminates in a run-out section where the thread gradually decreases in root depth and width and with the run-out section being of minimal axial length and being located closely adjacent the transition portion to produce a run-out zone of minimal axial length. A rolling die for forming the thread with minimal thread run-out having ridge segments with tapered end surfaces for providing the run-out thread with an end wall parallel to the transition portion and a method of making the bolt type fastener.Type: GrantFiled: October 29, 1998Date of Patent: November 21, 2000Assignee: Huck International, Inc.Inventor: Michael U. March
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Patent number: 6135892Abstract: The present invention provides a novel fastener member, stud, or other threaded member, for engagement with a female member, and the method of assembly thereof. The fastener member has a novel point which facilitates engagement of the fastener member in the threaded bore, greatly reduces the possibility of cross-threading and is especially suited for use in applications involving blind holes or the use of very thin threaded holes. The fastener member has a threaded shank portion. A point is provided at the end of the shank portion and includes an unthreaded radiused portion and a threaded transition portion between the shank portion and the radiused portion. The major diameters of the threads of the transition portion gradually lessen between the opposite ends thereof. The radiused portion can be provided with a truncated end surface.Type: GrantFiled: November 1, 1999Date of Patent: October 24, 2000Assignee: Textron Inc.Inventor: Steven P. Donovan
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Patent number: 6033313Abstract: A male screw which has a protrusion protruding from a thread thereof at least with regard to the normal direction to a flank of the thread. To obtain such male screw, a blank is introduced between rolling dies which are moved relative to one another and is rolled between the rolling dies to be formed with a thread. In this thread rolling process, the rolling pressure on an area of a die face of at least one of the rolling dies is determined to be higher than that in an ordinary thread rolling process and the rear end portion of the area of the die face is made to bite into the blank, causing the corresponding portion of the blank to be forced out to form the protrusion.Type: GrantFiled: November 13, 1998Date of Patent: March 7, 2000Inventor: Terufumi Nojikawa
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Patent number: 6024646Abstract: A swaged male element of a pipe connection of the type having a frusto-conical sealing surface adjacent to but separate from the load threads. The swaging is effected prior to final machining of the end of the pin and is followed by a cutting operation to remove surplus material from the interior surface of the pin. The swaging extends from the distal end of the pin proximally to include at least the distal end of the effective sealing surface, and preferably extends proximally to a point coinciding generally with the terminating proximal portion of the effective sealing area of the pin.Type: GrantFiled: October 2, 1997Date of Patent: February 15, 2000Assignee: IPSCO Enterprises Inc.Inventors: John F. Reed, Trent M. V. Kaiser
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Patent number: 6015351Abstract: A new machine for and method of manufacturing fluted pin fasteners and the pins produced thereby are disclosed which utilize a circular grinding arrangement of a plurality of grinders which grind flutes into a threaded pin. An internally threaded collar threads onto the pin. When the collar engages a surface of a work piece, resistance to further threading increases. When sufficient resistance to threading occurs, the driver deforms the lobes of the collar radially inward toward the axis of the collar. Material of the collar positioned internally from the lobes responds to deformation of the lobes and flows radially inward into the flutes of the pin to lock the collar, pin, and work piece together. The driver then rotates freely, and a joint has been made with a predetermined axial load thereby locking the component parts together.Type: GrantFiled: August 19, 1998Date of Patent: January 18, 2000Assignee: Fairchild Holding Corp.Inventors: Robin William Elcock, Albert K. Yamamoto, John A. Louw
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Patent number: 5979216Abstract: A wear-resistant tool insert for machines used in the manufacture of nails, screws, rivets and similar items from a wire starting material. The tool insert is of divided design in the axial direction of the supplied wire. Thus, during application of the tool insert it can "flex" in a controlled manner thereby reducing tensile stress in the tool insert, and reducing the possibility of fracture or breakage of the tool insert, when employed in an overload condition with unacceptably large tensile loads.Type: GrantFiled: March 27, 1998Date of Patent: November 9, 1999Assignee: Schwartzkopf Technologies, Corp.Inventors: Michael Schretter, Markus De Monte, Thomas Ginther, Reinhard Posch
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Patent number: 5947827Abstract: A method for reducing sliding friction of threaded fasteners according to the present invention includes the steps of providing a threadless austenitic stainless steel blank, coating the surface of the blank with a lamellar solid material, such as molybdenum disulfide, by introducing the threadless blank into a solution of molybdenum disulfide suspended within a carrying agent such as isopropanol or n-Butyl alcohol, heating the coated fastener to accelerate evaporation of the carrying agent, and forming threads into the coated surface using a thread rolling technique characterized by moving the blank through a series of traversing serrated dies moving in opposite directions parallel to one another to exert pressure on the coated surface, thereby both forming threads without removing metal from the surface, and impregnating the surface and near surface structure with the low friction species. Fasteners manufactured according to the present method exhibit reduced sliding friction and increased clamping force.Type: GrantFiled: January 14, 1998Date of Patent: September 7, 1999Assignee: A.P.L., LLCInventors: Philip O. Badger, Leon Wadsworth
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Patent number: 5871403Abstract: Method and apparatus are disclosed for forming dual synchronized threads on the interior and exterior cylindrical portions of a tube or pipe, and in the inner and outer cylindrical surfaces of an annular channel formed in an object. The method for producing dual synchronized threads includes initially defining a rotational zero point on the object where the first set of threads is to begin, cutting or forming the first set of threads, determining a rotational zero point on the object where the second set of threads is to begin, the second rotational zero point being relative to the first rotational zero point, and cutting or forming the second set of threads with the same lead as the first so that the two sets of threads will be synchronized and their starting points will be in some specified relationship to each other. An apparatus is also disclosed for cutting dual synchronized threads, the apparatus comprising a combination tap and die for simultaneously cutting dual threads on and in an object.Type: GrantFiled: January 7, 1994Date of Patent: February 16, 1999Inventors: John M. Simmons, Tom M. Simmons
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Patent number: 5842923Abstract: The screw comprises a circular thread portion 2a formed in a base portion of the screw, in which a helical thread is formed at the same depth and at the same crest angle; a special non-circular thread portion 2b which follows the portion 2a and has its thread depth gradually vary so as to assume a polygonal shape in cross section and permit the crest portion of thread to reach its highest points A-J in a turn of the thread, the highest points A-J being equal in thread depth and crest angle to the thread of the portion 2a; the portion 2b has its crest angle gradually increase as the thread moves from the highest points A-J to its lowest points along the length of the thread; and, lines connecting axially adjacent ones of the highest points A-J are tilted from the axis of the screw at a predetermined angle so that the portion 2b assumes a twisted polygonal prism-like shape as a whole.Type: GrantFiled: November 28, 1997Date of Patent: December 1, 1998Assignees: Minebea Kabushiki-Kaisha, Nissan Jidosha Kabushiki-KaishaInventors: Masaharu Umemura, Takashi Yamamoto, Ryoichi Nakayama
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Patent number: 5788441Abstract: The present invention provides an improved, lightweight, compact threaded fastener that has a relatively shortened transition thread rollout zone between the grip of the fastener and the threaded shank of the fastener. This transition zone is shortened due to the fact that the runout (or inner end) of the rolled thread on the fastener extends no more than one-third the circumference of the rolled thread at its pitch diameter. The short runout of the rolled thread does not compromise the strength of the fastener, because the runout does not have a relatively abrupt transition. Instead, the depth of the runout of the rolled thread of the fastener gradually decreases along its length from a depth equal to the uniform depth of the rolled thread throughout the length of the threaded shaft of the fastener to no depth at the very end of the runout. The invention further provides a pair of thread rolling dies for producing such an improved, lightweight, compact threaded fastener.Type: GrantFiled: January 3, 1997Date of Patent: August 4, 1998Assignee: West Coast Aerospace, Inc.Inventors: Nicholas C. Karabestos, Gary L. Stewart
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Patent number: 5782697Abstract: A method of making a shaft abutment screw, especially for axial engagement with an armature shaft of an electric motor, includes the following steps:(a) pressing out a flat mild steel blank,(b) subjecting the blank to a drawing operation so as to form a hollow component comprising a generally flat radial base wall and a generally cylindrical skirt portion extending from the base wall and describing a screw driving socket within it,(c) machining a screw thread on the outside of the skirt portion, and then(d) nitriding the component.A shaft abutment screw having a flat base portion joined to an externally threaded cylindrical skirt portion, within which a hexagonal screw driving socket is formed, is also described per se. The invention is applicable especially to motorised reduction gear units for driving motor vehicle screen wipers for windshields and rear windows.Type: GrantFiled: April 9, 1996Date of Patent: July 21, 1998Assignee: Valeo Systemes D'EssuyageInventors: Stephane Hommelet, Xavier Savy
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Patent number: 5743123Abstract: In a method of thread rolling a screw shaft, an inclining portion 1c is provided between a machining portion 1a of a screw shaft 1 and a non-machining portion 1b thereof as well as a taper portion 2b is formed to screw groove forming dies 2, by which a machining load concentrating at the thread rolling portion on the end of the dies adjacent a chuck can be reduced. With this method, the screw shaft can be thread rolled to have straightness of high quality.Type: GrantFiled: January 31, 1997Date of Patent: April 28, 1998Assignee: Mitsuba CorporationInventors: Masatoshi Yamamoto, Hiromasa Hosono
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Patent number: 5660594Abstract: A process for forming a screw thread on a corrugated bar used in concrete reinforcement joints such as anchor bolt joints. The ribs and flank fillets are removed from the end portion of the corrugated bar to be threaded. The end portion is then heated in a controlled manner such that the temperature of the end portion is highest at the end and falls smoothly toward the beginning of the ribless portion of the bar. The bar is immovably locked in place and the end portion is pressed by a movable cylindrical mold. Due to the temperature difference along the end portion, hot upsetting sets in at the end and advances toward the beginning of the ribless portion and the cross-sectional area of the end portion expands to become equal to an inner diameter of the mold. A screw thread is then formed on the end portion of the bar, the cross-sectional area of the screw thread being at least equal to the cross-sectional area of a remainder of the bar and the thread being longer than a diameter of the bar.Type: GrantFiled: February 22, 1995Date of Patent: August 26, 1997Assignee: Tartuntamarkkinointi OyInventor: Kari Viljakainen
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Patent number: 5636549Abstract: Producing novel threaded members such as lead screws (10, 20) by winding and anchoring a hardened tempered spring wire (14, 16) around a support body such as a screw shaft (11, 15) to form a hard, smooth thread comprising a wear-resistant running surface for engagement with a bearing nut member (43) in an adjustment assembly (30), such as for a zoom lens. The shaft (11) may be shallow-grooved (13) to determine the pitch of the threads. Alternatively the shaft (15) may be wound with contacting thread wire (16) and spacer wire (17) to determine the pitch of the thread.Type: GrantFiled: December 22, 1993Date of Patent: June 10, 1997Assignee: Hughes ElectronicsInventor: Gabor Devenyi
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Patent number: 5547424Abstract: In a method of making an elongate object (49) with a head at one end and a point at the other end, a blank (49) is placed in a die (50) having a through-going channel, following which the head end is subjected to axial pressure by a tool (52), while a stop member (55) is kept engaged with the die (50) at its other end. A pre-formed head is initially provided on the blank (49) so that the head has an excess of material with respect to the size of the final head. A cavity (56) is formed in the stop member and is in extension of the through channel. When blank (49) is subjected to axial pressure the tool (52) causes flow of material in the shank of the blank (49) so that blank material flows into the cavity (56) of the stop member.Type: GrantFiled: October 14, 1994Date of Patent: August 20, 1996Assignee: Enkotec A/SInventor: Ove Nielsen
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Patent number: 5250007Abstract: Apparatus and methods for forming a thread of varying pitch by utilizing a threading assembly which includes a plurality of threading elements having thread cutting or forming portions on the different elements for engaging the work piece at different locations, with the assembly and work piece being driven both rotatively and at the same time axially relative to one another to form the thread. The rate of axial advancement per revolution between the work piece and each of the threading elements is varied, and the elements of the assembly are also shifted axially relative to one another during the rotary and axial movement, to give the thread its varying pitch.Type: GrantFiled: September 9, 1992Date of Patent: October 5, 1993Inventor: William P. Green
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Patent number: 5234291Abstract: The roof bolt tendon comprises a length of square twist steel with a partial thread formed directly thereon over at least part of its length. The partial thread, which may extend for the full length of the tendon and which is preferably formed by rolling, is composed of thread portions formed at the corners of the square cross-section of the square twist steel. A roof bolt in which the tendon is employed is also disclosed.Type: GrantFiled: April 7, 1992Date of Patent: August 10, 1993Assignee: Hugo TrusteesInventor: Theodore D. Swemmer
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Patent number: 5221234Abstract: A cutting device and method for its operation are utilized to apply variably canted threads to a screw blank. A conventional cutting lathe is provided with a conventional hydraulically operated adjustable cutting support attached thereto. A guide plate is generally mounted upon the lathe adjacent the armature, which is guided therealong to produce a particular pattern in the workpiece. The armature is pivotable to permit cutting at particular angles into the surface of a workpiece. A secondary guide is utilized in producing a controlled variable pivot of the cutting armature during its progression along the body of the workpiece. The secondary guide is rigidly mounted to the adjustable cutting armature and precisely controls its movement during the cutting operation, producing a cutting operation having dual movement characteristics.Type: GrantFiled: January 23, 1992Date of Patent: June 22, 1993Inventor: Andrew Pakos
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Patent number: 5127783Abstract: A carbon and/or ceramic fiber reinforced carbon and/or ceramic matrix composite threaded member including a core, a fiber containing thread-defining element bonded to the exterior of the core and a reinforcing fabric layer securing the thread-defining element to the core. The thread-defining element may be an integral part of a tubular braided reinforcing fabric or applied to the core prior to application of a reinforcing fabric layer. Externally and internally threaded members and methods for their manufacture are described.Type: GrantFiled: May 25, 1989Date of Patent: July 7, 1992Assignee: The B.F. Goodrich CompanyInventors: Sharad R. Moghe, Mark J. Purdy, Wei-Teh Shih, James A. Tallon