Abstract: A device and method for a trackable suction tool in surgical use. A trackable suction tool involves a tubular handle with a main tube and an entrance tube extending from the main tube, a flattened section of the main tube with a suction-regulating orifice, a tip coupled with the main tube distal end and a tracking mechanism coupled with a handle proximal end. A method of tracking position of a trackable suction device involves attaching a tip to a handle in one of a plurality of fixed positions, attaching a tracking mechanism to the handle in one of a plurality of fixed positions, calibrating the position of the tip with a positional tracking system using the tracking mechanism, positioning the tracking markers in view of the positional tracking system, and tracking a position of the distal end of the tip of the suction device.

Abstract: A nail screw, in particular for connecting facade boards or terrace planks made of wood, especially real wood, has a shaft, a conical tip formed at the front end region of the shaft and a head formed at the rear end region of the shaft. A thread has a forward facing insertion flank and a rearward facing grip flank between the conical tip and the head. The thread is a double thread, wherein a grip flank angle (?) measured between the grip flank and a plane perpendicular to the longitudinal axis of the nail screw is between 25 and 35 degrees, more preferably between 28 and 32 degrees, most preferably 30 degrees. The conical tip has a tip angle (?) between 80 and 120 degrees, more preferably between 90 and 110 degrees, most preferably of 80, 90 or 100 degrees.

Abstract: A panel fastener is provided that has a head having a first surface and a second surface opposite the first surface; an engagement feature on the first surface of the head, the engagement feature being configured to be engaged by a driving tool; a shank extending from the second surface of the head; a threaded portion extending from the shank, the threaded portion having first and second helical threads arranged in an intertwined manner; the first thread extending farther radially from the central axis than does the second thread; and the shank being located between the head and the threaded portion.

Abstract: A screw with an asymmetrical thread for securing wooden members together is disclosed. The screw includes a shaft with a head at one end and a tip at the other end. A continuous asymmetrical thread extends along the shaft. The asymmetrical thread has a front surface facing the tip and a rear surface facing the head, the front and rear surfaces each having an angle relative to a plane normal to the shaft. The asymmetrical thread has a first section and a second section. The portion of asymmetrical thread in the first section has front and rear surfaces of first angles with respect to the plane normal to the shaft. The portion of asymmetrical thread in the second section has front and rear surfaces of second angles different than the first angles. The asymmetrical thread includes a transition portion between the first and second sections.

Abstract: A fastener may include an elongated shank, a head at a distal end of the shank, and a drill point at a terminal end of the shank, which is opposite to the distal end. The fastener may include a primary thread starting at the drill point and extending along the shank towards the head. The fastener may include a secondary thread starting at the drill point, extending along the shank towards the head, and stopping in an axial direction before the primary thread ends. The secondary thread may be radially located 180 degrees from the primary thread. The drill point may include a plurality of radially extending cutting edges and one or more relieved flute portion extending along the surface of the drill point.

Abstract: An interlocking thread with a tooth-cross-section that is wider at its crest than at its root and with “V” angles located both along the crest and the root which tightens into a tapped hole that has a similar thread cross-section.

Abstract: The present disclosure relates to a system for the fixing of bone segments or bone fragments comprising an implant plate or an implant surface plate having a bore or a cut-out and comprising an implant screw which can be guided through the bore or cut-out of the plate, wherein the implant screw has a screw shaft and a screw head and wherein both the screw shaft and the screw head have a thread with identical pitches.

Abstract: An implant can include a core having a head portion and a stem portion extending from the head portion. The stem portion can include an intermediate threaded section, a first porous section located along the stem portion, and a second porous section located along the stem portion, wherein the intermediate threaded section of the stem separates the first porous section from the second porous section.

Abstract: A surgical instrument system that includes a housing and a rotatable drive shaft, a motor operably coupled to the drive shaft, and a plurality of replaceable end effectors that can be connected to the housing. Each replaceable end effector includes a drive screw that is turned a fixed number of revolutions by the motor-driven rotatable drive shaft when the end effector is connected to the housing. Each end effector further comprises a firing member operably coupled with the drive screw of the end effector. The drive screw is configured to displace the firing member over a firing length as a result of the fixed number of revolutions. In certain embodiments, each replaceable end effector can include a drive screw with a thread pitch set to the firing length divided by the fixed number of revolutions.

Abstract: A screw with a head that includes a flat area with a first indented area located centrally within the head and a second indented area located centrally within the first indented area, and all three areas provided with grooves for engagement with tools. A screw driver having mating ridges that insert within the grooves on the first indented area rotates the screw to insert it into a substrate. A rescue driver engages the grooves of the flat head and second indented area to remove the screw from the substrate when the grooves in the first indented area become stripped. The head of an alternate screw is provided centrally with a reverse threaded female channel engagable by a reverse threaded rescue driver to remove the screw from a substrate when the grooves in the alternate screw's head that are used to insert the screw into a substrate become stripped.

Abstract: A screw fastener having a head, threaded shank with compound, divided threads and tip end has an upper thread surface extending at a substantially flat angle from a normal to a longitudinal axis of the screw which diverts upwardly to a first peripheral edge defining a cupped or concave upper thread surface and a lower thread surface extending upwardly to a second peripheral edge, with a radially inward recess between first and second edges. The screw exhibits significantly increased pull-out resistance.

Abstract: A bone screw comprises a threaded portion. The threaded portion has a first thread including a first front surface (11), a first back surface (12) and a crest. A second thread including a second front surface (16) and a second back surface (17) is formed on at least part of the crest of the first thread. Because of the presence of the second thread, a contact area between the screw and a bone and an axial pullout force-bearing area are both significantly increased, without significantly influencing the bending resistance, so that the mechanical property of the screw is entirely improved.

Abstract: A weight screw for a golf club head having one or more weight ports is disclosed herein. A set of weight screws is also disclosed herein, the set comprising at least one low-weight screw comprising multiple materials and at least one weight screw comprising a single material.

Abstract: The present invention pertains to a bimate screw providing with a first section alternating with a second threaded section; wherein, the second threaded section has a smaller outer diameter than the first threaded section, and further a plurality of concavities are disposed on each thread of the second threaded section for defining two flanks therein. In this manner, both the first and the second threaded sections facilitate to sever and shatter cuttings so as to reduce the screwing resistance and prevent the object from being damaged under the accumulation of cuttings; simultaneously, the bimate screw effectively attains to a good resistance of extraction from the object by the concavities receiving the remaining cuttings which are not guided out of the object.

Abstract: A screw includes a shank, at least one end cutting groove, a first thread, and a second thread. The shank includes a lower section disposed near an insertion end thereof and an upper section disposed near a head end thereof. The lower section has triangular transverse cross sections, and the upper section has circular transverse cross sections. The end cutting groove is formed in the lower section of the shank, and an included angle between 3 and 9 degrees is formed between an extending direction of the end cutting groove and a longitudinal axis of the shank. The first thread is disposed on the lower section of the shank and includes a plurality of asymmetrical thread convolutions.

Abstract: A variably threaded screw has a first end and a second end, the first end of the shaft terminating in a tip and the second end having a widened head thereon. A first helical thread portion is located on the shaft adjacent the widened head. A second helical thread portion is located on the shaft adjacent the tip of the shaft. A third helical thread portion is located on the shaft between the first helical thread portion and the second helical thread portion. The first helical thread portion and the second helical thread portion have right hand thread pitches. The third helical thread portion has a left hand thread pitch. A helical ridge having a right hand thread pitch intersects the third helical thread portion.

Abstract: A tie bolt for joining two parts together has a shaft. The shaft in turn has a primary thread for engaging a first part and a secondary thread for engaging a second part, wherein the primary thread and the secondary thread have different pitches. The tie bolt may be used to join together any two parts which are to be locked together to transmit torque.

Abstract: A screw capable of drilling and cutting includes two inclined cutting planes with a cutting edge formed on a convergence of the cutting planes. A tapered positioning member extends from the convergence of the cutting planes, where the cutting edge is divided into dual sub cutting edges by means of the positioning member. Each sub cutting edge has an inclined angle. An included angle included by the sub cutting edges is smaller than 180 degrees. Threads spiral on a shank and extend to the sub cutting edges. Setting the positioning member against on an object permits a steady performance during the first stage of screwing. Subsequently, the sub cutting edges provides a scraping effect on the object during drilling. Torque is reduced and drilling speed is promoted.

Abstract: A weight screw for a golf club head having one or more weight ports is disclosed herein. A set of weight screws is also disclosed herein, the set comprising at least one low-weight screw comprising multiple materials and at least one weight screw comprising a single material.

Abstract: A screw includes a positioning member defined on inclined cutting planes of a drilling portion of the screw for stably allowing a cutting edge constructed at a convergence of the cutting planes to cut efficiently. A threaded section formed on a shank of the screw is extended toward the cutting edge and connected with one end of the cutting edge. The positioning member helps the screw fixedly stand on an object. The cutting edge and the cutting planes allow cutting debris to be swiftly and smoothly extruded therefrom into the threaded section for avoiding the piling of the considerable cutting debris. Thereby, the screwing torque is reduced and the drilling speed is promoted. Preferably, the fastened screw is sunken in the object, and the fastening operation is completed successfully.

Abstract: An anti-loose screw suitable for fastening various construction work pieces comprises: a screw head; a cylindrical rod, coupled to the screw head; a high thread and a low thread, spiraling around the cylindrical rod, and uniformly distributed on the cylindrical rod, wherein the crests of the low thread on the cylindrical rod are machined by a cutter to form cut slots and irregular burrs. When the screw is driven into a construction work piece, those two uniformly distributed high and low threads can keep the balance of the advancing screw so that the advancing screw can be free from any deviation. Further, the extruded scraps will be concentrated to provide a superior anchoring effect. Furthermore, in cooperation with the wrapping effect of the expanding material of the work piece, the cut slots and burrs formed via the machining of a cutter can raise the anti-loose capability of the screw.

Abstract: A bone screw having a threaded proximal portion, a threaded median portion, and a threaded distal portion. The threaded proximal portion has a proximal thread with a constant diameter and a proximal pitch. The threaded median portion has a median thread with a constant diameter smaller than the diameter of the proximal thread and a median pitch that becomes increasingly smaller from a distal end of the threaded median portion towards a proximal end of the threaded median portion. The threaded distal portion has a distal thread having a constant diameter that is smaller than the diameter of the median thread and a distal pitch that is larger than the median pitch at the distal end of the threaded median portion.

Abstract: An anti cross-thread bolt which prevents the bolt from being cross-threaded without the need for correcting its posture by a pilot portion. The bolt is screwed into a female screw having a nominal diameter D and an inner diameter D1. At the tip of a regular thread part formed on the bolt shank, a small-diameter thread part is formed by one pitch or more, the small-diameter thread part having an outer diameter d which is larger than an inner diameter D of the female screw and smaller than (D+D1)/2. When the bolt is obliquely screwed into the female screw, the small-diameter thread part is brought into contact with the female screw at one point, but the bolt is allowed to rotate around the point. Thus, the occurrence of cross-threading is prevented.

Abstract: Tapping screw (1) has conical portion (4) at the end of cylindrical portion (3) and thread (6) of tapered screw portion (M) disposed at conical portion (4) are formed of single-start threads roughly pitched, wherein the tip angle of conical portion (4) is conically formed at an acute angle of about 30 degrees, and second thread (7) extending in parallel with thread (6) of tapered screw portion (M) is disposed at the end of conical portion (4), forming double-start thread (6, 7) at the end of conical portion (4), and the axial length of tapered screw portion (T) formed of double-start thread (6, 7) is greater than the thickness (upper limit 1.6 mm) of the metal sheet to be fastened.

Abstract: A spoke of a bicycle rim has a spoke body having a connecting end and a threaded segment formed on the connecting end. The threaded segment has multiple first thread sections and at least one second thread section. The first thread sections have a major radius, a minor radius and a pitch. The at least one second thread section is formed between the first thread sections to form at least one loosen-proofing section between the first thread sections and has a major radius, a minor radius and a pitch. The major radius of the second thread section is smaller than the major radius of the first thread sections. The minor radius of the second thread section is larger than the minor radius of the first thread sections. The pitch of the second thread section is the same as that of the first thread sections.

Abstract: A screw for composite or plastic material comprises a head having a socket which is rotatably couplable for application of a torque. An elongated shank extends from the head and terminates a tapered threaded distal tip. The shank has one portion having an enlarged diameter and a second portion having a reduced diameter. The first portion is traversed by a left hand thread having a first pitch. The second portion is traversed by a right hand thread having a second pitch which is less than the first pitch. An unthreaded land portion adjacent the tip extends at least twice the second pitch. For some embodiments, some thread segments have notches. The fastener is particularly adapted for very dense material.

Abstract: A device for manipulating bone fragments includes a bone screw includes a shaft extending along a longitudinal axis. The shaft includes a first end having a first threaded portion with a first core diameter, a first external diameter and a first pitch. The shaft includes a second end having a second threaded portion with a second core diameter, a second external diameter and a second pitch. The second end further has a tool engaging surface, wherein the first external diameter is no greater than the second core diameter, the first and second pitches are substantially equal, and a non-threaded middle segment between the first and second threaded portions, an outer diameter of the middle segment being smaller than the first core diameter, and wherein the shaft includes a cannulation extending therethrough disposed coaxial with the screw longitudinal axis.

Abstract: A screw anchor includes a body having a head end that extends to a tip end through an intermediate portion defining an axis of the screw anchor, and a plurality of threads extending along the intermediate portion. Each of the plurality of threads includes a head side surface having a first angle relative to an axis perpendicular to the axis of the screw, and a tip side surface having a second angle relative to the axis perpendicular to the axis of the screw. The first angle is between about 30° and about 40°, and the second angle is between about 15° and about 25°.

Abstract: The invention relates to a system comprising a composite anchor bolt (10) and glue (12), wherein the bolt (10) can be screwed directly into a bore (14) that is at least partially provided with the glue (12) and is introduced in a fixed anchoring base (16), wherein the bolt (10) has a bolt head (18) having a tool application element, a substantially cylindrical shaft (20), and two or more, however, preferably three thread turns (22, 24, 26), which are disposed parallel to each other and extend helically at least partially across the length of the shaft (20), wherein the respective distance (p1, p2, p3) between the thread turns (22, 24, 26) is selected such that the glue (12) present in the bore (14) is evenly distributed between the wall (32) of the bore (14) and the bolt (10) upon screwing the bolt (10) into the bore (14).

Abstract: Non-dimpling fasteners and methods of installing non-dimpling fasteners are provided herein. Non-dimpling fasteners can include a body including a first end and a second end, a tip at the first end of the body, a head at the second end of the body, a first body portion adjacent to the tip, a second body portion adjacent to the head, and a shoulder adjacent to the first body portion and the second body portion. The first body portion can have a first diameter and can include a first thread. The second body portion can have a second diameter that is larger than the first diameter of the first body portion. The shoulder can have an angle with respect to a longitudinal axis of the fastener.

Abstract: A screw, in particular a self-tapping screw, has a screw thread which covers up to the front end of the screw formed as a drilling tip or cutting tip. In the front area, starting with a distance from the front end of the screw, there is an opposite thread showing the same pitch as the screw thread, however, its thread height is lower than the thread height of the screw thread. This second, opposite single-thread, double-thread or triple-thread/multi-thread forms a cutting edge with its thread edge which is used to cut fibers in order to reduce wedge effect during screwing in the screw. The screw is particularly suitable for wood or wood-like materials in the edge areas of structural elements.

Abstract: A pedicle screw assembly, including: a bone screw having a head portion and a thread portion, wherein the thread portion includes an axial shaft and a triple lead thread disposed about the axial shaft; and a rod retention member selectively coupled to the head portion of the bone screw. Optionally, the triple lead thread includes leads that originate at different points along the axial shaft. Optionally, the triple lead thread includes leads that terminate at different points along the axial shaft. Optionally, the axial shaft includes a first tapering portion proximate a tip of the axial shaft. Optionally, the axial shaft includes a second tapering portion proximate the tip of the axial shaft. Preferably, the second tapering portion tapers more steeply than the first tapering portion. Optionally, the axial shaft includes a reduced diameter portion proximate the head portion. Optionally, the axial shaft includes one or more tapering portions proximate the head portion.

Abstract: A hole-forming and thread-forming screw for screwing into a sheet piece, including a slotted screw head for accommodating a tool, a threaded shank and a tapering hole-forming part having outer sides with a continuous convex-shaped curve along an entire length thereof, ribs running like threads along the hole-forming part being provided. The hole-forming part ends in a rounded, blunt end piece, and the rounded ribs, which chiplessly displace the material of the sheet part, are situated symmetrically opposite one another and have a pitch that is a multiple of the thread pitch.

Abstract: A versatile fastener including at least two flat areas formed on a cutting part, and an accommodating area disposed between any two of the flat areas. At least two cutting faces are convergent to form the accommodating area, and first and second cutting edges are respectively formed at a connection between each cutting face and flat area. In operation, the flat areas facilitate the first and the second cutting edges to promote a stable balance with the object, thereby allowing the debris to be swiftly guided out of the accommodating areas. Consequently, it is difficult to crack the object while imparting forces thereon, so as to lower the screwing resistance and the fastening torque as well as increase the combining efficiency.

Abstract: A fastener configured to couple a first substrate to a second substrate may include a head, a shank, and a tip. The shank may have a generally constant diameter between the head and tip, and the shank may include an unthreaded portion proximate the head, a threaded portion proximate the tip, and a reverse threaded portion therebetween. The threaded portion may include a plurality of right handed threads that continue onto the tip, and the reverse threaded portion includes a plurality of left handed threads. The unthreaded portion may have an axial length greater than an axial length of the reverse threaded portion. In addition, the fastener may include one or both of a cut extending radially inward toward the fastener axis proximate the tip and serrations on at least one of the plurality of right handed threads.

Abstract: A bone screw (1) having a threaded proximal portion (2), a threaded median portion (3), and a threaded distal portion (4). Threaded proximal portion (2) has a core (11) with a constant diameter and a proximal thread (12) with a constant diameter and a proximal pitch (P2). The threaded median portion (3) has a core (15), which is conical, with a diameter becoming increasingly larger from the distal end of the threaded median portion (3) to the proximal end thereof, and thread (16), which has a constant diameter smaller than the diameter of the thread (12) of the proximal threaded portion (2). The pitch of thread (16) of the threaded median portion (3) becomes increasingly smaller from the distal end of the threaded median portion (3) towards its proximal end. At the proximal end of the threaded median portion (3), the pitch of thread (16) is larger than the pitch (P2) of the thread (12) of the threaded proximal portion (2).

Abstract: A bone screw is provided having first and second threaded portions of different diameter separated by a middle portion that is unthreaded so that the bone screw may be inserted into a pair of adjacent bone fragments and used to compress the fragments together by driving the screw into a hole drilled in the fragments. An installation tool is also disclosed for threadably engaging one end of the bone screw and is used to initially drive the screw into the bone hole. Thereafter, a screwdriver may be inserted through the tool and into engagement with a recess in the bone screw and may be used to drive the screw fully into the bone and to separate the bone screw from the installation tool. A method of installation is further provided.

Abstract: Fasteners are provided that include a head and having a head, a tip end having a tip, a first body portion having first threads having a pitch angle, and a second body portion having second threads, the second threads having a different pitch than the first threads. The first body portion is adjacent to the tip end of the fastener and extends a first distance along a length of the fastener towards the head end. The second body portion is adjacent to the first body portion, and extends the head end of the fastener and extending a second distance along the length of the fastener towards the head end.

Abstract: A fastener adapted for anchoring engineered lumber panels has a threaded portion with a double included securement thread having an included angle between 15° and 25°. The ratio of the major thread diameter to the minor diameter exceeds 2.0 to provide a large thread surface to resist pull out. The fastener also includes a drill tip having an effective diameter substantially equal to the minor diameter of the thread. The fastener is configured to resist cocking upon being driven into the engineered lumber panel and to resist marring of the panel fascia.

Abstract: An improved screw includes a head and a shank. The head has a wrench cavity on the top to be driven by a screwdriver. The shank is connected to the bottom of the head. The shank has a round shank at an upper end close to the head to form a left-hand thread section, and a triangular shank at a lower end to form a right-hand thread section. The left-hand and right-hand thread sections have thread points formed in an asymmetrical manner. The right-hand thread section further has an upper thread section and a lower thread section at the bottom to form the tip. The lower thread section has saw-toothed threads. Thus tapping efficiency improves when the screw is fastened to a workpiece, and faster and firmer fastening can be achieved.

Abstract: An anti-cross threading screw (1) includes a first threaded portion (4) including a first thread (5) having a first outer diameter (6) and a first pitch (9) and a second threaded portion (12) having a second thread (13) having second outer diameter (18) and a second pitch (21). The second threaded portion (12) is designed as an anti-cross threading portion. The second thread (13) has enlarged an thread crest (15). The second outer diameter (18) of the second thread (13) is smaller than the first diameter (6) of the first thread (5). The first pitch (9) of the first thread (5) is different than the second pitch (21) of the second thread (13).

Abstract: A compression pin for urging two bone regions together includes a pin body having a distal end, an opposed proximal end, a first threaded region, and a second threaded region. The first threaded region is positioned near the distal end, and the second threaded region is positioned near the first threaded region. The first threaded region includes a first thread having a FT leading surface that is at a FT leading angle, and the second threaded region includes a second thread having a ST leading surface that is at a ST leading angle that is different than the FT leading angle. During insertion of the compression pin, the first threaded region and the second threaded region cooperate to aggressively compress the bone regions together.

Abstract: An object of the present invention is to provide a duplex threaded body having a right-handed thread and a left-handed thread on the circumferential surface of a single solid member. In addition, an object of the present invention is to provide a single-nut or double-nut type internally-threaded body that demonstrates a locking effect even at an intermediate position without substantially loosening by using a combination of a duplex externally-threaded body and one or more internally-threaded bodies. Moreover, an object of the present invention is to provide a screw structure in which a pair of internally-threaded bodies can only be removed by destruction once they are mutually coupled when screwed onto a duplex externally-threaded body, thereby making it possible to impart tamper-proof characteristics in addition to a locking effect.

Abstract: Fasteners are provided that include a head and having a head, a tip end having a tip, a first body portion having right-hand threads, and a second body portion having left-hand threads. The first body portion is adjacent to the tip end of the fastener and extends a first distance along a length of the fastener towards the head end. The second body portion is adjacent to the first body portion, and extends the head end of the fastener and extending a second distance along the length of the fastener towards the head end. The right-hand threads, and the left-hand threads, can have a pitch angle ? of less than about 60°.

Abstract: To provide an anti cross-thread bolt which prevents itself from being cross-threaded without the need for correcting its posture by a pilot portion. The bolt is screwed into a female screw having a nominal diameter D and an inner diameter D1. At the tip of a regular thread part 11 formed on a bolt shank, a small-diameter thread part 12 is formed by one pitch or more, the small-diameter thread part having an outer diameter d which is larger than an inner diameter D of the female screw and smaller than (D+D1)/2. When the bolt is obliquely screwed into the female screw, the small-diameter thread part 12 is brought into contact with the female screw at one point, but the bolt is allowed to rotate around the point. Thus, the occurrence of cross-threading is prevented.

Abstract: A fastening screw bolt includes a head connected to a screw rod. The screw rod includes a helical thread having a plurality of helical turns each of which turns one revolution around the screw rod. Each helical turn has a helical cutting edge formed with at least two angularly spaced apart notches. With the notches, the screw bolt can achieve an improved engagement with a hole into which the screw bolt is inserted.

Abstract: A screw includes a shaft, a trumpet-shaped head provided to a base end of the shaft, and a narrow-tip portion formed at a tip end of the shaft. The shaft has different diameters at a small-diameter portion contiguous to the narrow-tip portion and at a large-diameter portion contiguous to the head. Two screw threads are formed on the small-diameter portion and one screw thread is formed on the large-diameter portion. Therefore, a thread portion can be divided into a double-thread portion and a single-thread portion. It is preferable that the screw threads forming the double-thread portion have different heights. The screw is mainly used for fastening a plasterboard to a frame member.

Abstract: An expanding screw for an expandable dowel sleeve (31) has a shaft (12) having a rotation-transmitting element (15) provided at its first end (13), at least one first screw thread (19) extending from its second end (17), and a thread section (21) provided in a region of the at least one first thread (19), spaced from the second end (17), and having at least one further screw thread (23).

Abstract: A concrete bolt includes a hexagonal head part and a bolt body extended from the head part. A bottom end of the bolt body is a bevel, a surface of the bolt body has high-tooth and low-tooth threads helically extended and arranged alternately. A tooth end of the high-tooth thread is tilted outward, an end surface facing toward the head part is concaved, the low-tooth thread is roughly in a trapezoidal shape and a high-tooth thread adjacent to the bottom end has petal-shaped teeth arranged alternately. When locking into concrete, the bolt is operated more easily to save labor work by cutting with the high-tooth threads and guiding and balancing functions with the low-tooth threads. Additionally, the concrete cut is coagulated after locking, thus the bolt is more robust by having a high tensile strength and easily dismantled for repetitive use, thereby improving a practical value of the concrete bolt.

Abstract: An improved anchor device or fastening member which is particularly suited for use in the attachment of various fixtures and equipment to masonry, concrete, and other hard and/or friable substrates includes a head and a shank depending therefrom. The shank has a first threaded portion having a predetermined thread angle and a predetermined hardness, and a second threaded portion having a predetermined thread angle and a predetermined hardness. The first threaded portion is proximate to the head and the second threaded portion extends from the first threaded portion. The thread angle of the first threaded portion is different than the thread angle of the second threaded portion. In addition, the hardness of the first threaded portion is softer than the hardness of the second threaded portion. This provides for a more ductile anchorage when the fastening member is engaged with the substrate.