Abstract: A washer has a body having an axis and provided with a first face surface located at one axial side and adapted to cooperate with a nut, a second face surface located at an opposite axial side and adapted to cooperate with an object to be assembled or disassembled, and at least one additional turning resistant surface adapted to cooperate with a bolt, the additional turning resistant surface of the body being formed as a frictional surface providing a friction between the body and the bolt to frictionally impede the bolt from turning and at the same to allow the bolt to be displaced in an axial direction when the nut is turned, the second face surface of the body being formed to provide a friction between the body and the object and therefore to impede the body from turning, and the first face surface of the body being formed with a smaller frictional characteristic than the second face surface of the body to at least reduce dragging of the body into turning by the turning nut; and a fastener is provided with

Abstract: A join structure comprises a box section column and spit T-section joined by a high strength bolt and a method secures a nut to an inside of the box section column. A Torque-Shear type high strength bolt is tightly tightened by a controlled tension and a joining method of a steel member uses that bolt. The join structure is comprised of a box section column, a split T-section attached to its outer surface, and a high strength bolt inserted from the outside of the split T-section and fastened with the nut. The nut is secured to the box section column by joining a sleeve secured to a washer formed integrally with the nut and a sleeve of a nut holding part from the outside of the column. The Torque-Shear type high strength bolt has a pintail for controlling the torque at its top.

Abstract: A retaining device is designed to retain a portion of an assembly device. The portion of the assembly device is released during failure of the assembly device. The retaining device includes a fixed part, a mobile part capable of sliding with respect to the fixed part, a housing, formed with both the fixed part and the mobile part, a return device, which can be compressed during a parts assembly operation. The return device can be relaxed when the assembly device fails, which causes sliding of the mobile part with respect to the fixed part, such that the portion of the assembly device is retained in the housing.

Abstract: A fastener for fastening a component having a mounting hole has an essentially U-shaped clamping region that at least partially grips around the component and has two opposing legs that are connected together as a single piece by a connecting region. The legs are provided with through holes that serve to accommodate a pin or stud that passes through the mounting hole of the component. A nut is attached to a first leg on the side facing away from the second leg such that the connection between the first leg and the nut can be released by a separating force acting on the nut.

Abstract: A washer has a body having an axis and provided with a first bearing face surface located at one axial side and adapted to cooperate with a nut, a second bearing face surface located at an opposite axial side and adapted to cooperate with an object, at least one third turning resistant surface adapted to cooperate with a thread of the bolt, the body having at least one resistive point arranged so that when the nut is turned and turns the bolt the body of the washer stops the bolt from turning and thereby the nut creates a pull on the bolt which elongates the bolt in an axial direction and applies to the body of the washer an axial force which overcomes the at least one resistive point so that a portion of the body of the washer is allowed to be pulled axially when the bolt elongates.

Abstract: A screw having a screw-threaded shank and a circular head, the head being provided with three radially extending screwdriver tip receiving portions defined between three first, off central integrally formed projections designed to become shaved-off the screw head by a pre-set force applied during tightening of the screw, and three second, integrally formed projections designed to withstand a shear force greater than the pre-set force applied during slackening of the screw.

Abstract: A washer which has a body having a first bearing face surface at one axial side and adapted to cooperate with a nut, a second bearing face surface at an opposite axial side and adapted to cooperate with an object, at least one third turning resistant surface adapted to cooperate with a thread of the bolt, and at least one breaking point arranged so that when the nut is turned and turns the bolt the washer stops the bolt from turning and thereby the nut creates a pull on the bolt which elongates the bolt in an axial direction and applies to the washer an axial force which breaks said body of the washer and allows a portion of said body of the washer to be pulled axially when the bolt elongates; and also a fastener, a method of fastening objects, and a tool for fastening objects can be provided with the new washer.

Abstract: A roof bolt comprises a shaft for insertion in a hole drilled in a mine roof and a head whereby the bolt may be rotated, the head being offset with respect to the longitudinal axis of the shaft so that when the bolt is rotated by means of its head the shaft is caused to describe a circle of greater diameter than its own diameter, and where the offset is at least 0.08 inch and not more than 0.25 inch. Preferably the offset is from 0.10 to 0.16 inch. The invention includes a method for the production of roof bolts which comprise a shaft for insertion in a hole drilled in a mine roof and a head whereby the bolt may be rotated, the method being characterised by being controlled so that at least 90% of the bolts produced have their head central axis offset with respect to the longitudinal axis of the shaft by an amount of at least about 0.08 inch and not more than about 0.25 inch.

Abstract: A fastener including a head having a screw driver or wrench engagement feature. The fastener includes a threaded shank extending from the head. A plurality of voids or scores in the shank spaced from but near the head permit rotational torque on the head in one direction significantly greater than rotational torque in an opposite direction so that rotational torque in an opposite direction causes the head to break off from the shank.

Abstract: The invention comprises a roof bolt and nut in screw threaded engagement, said bolt comprising a shaft for insertion in a hole drilled in a mine roof and a threaded portion engaged by the nut whereby the bolt may be rotated. The nut is offset with respect to the longitudinal axis of the shaft of the bolt so that when the bolt is rotated by means of the nut, the bolt is caused to describe a circle of greater diameter than its own diameter, the amount of said offset being from about 0.015 to about 0.50 inches. Preferably the offset is from about 0.02 to about 0.25 inches. The nut may be releasably locked in screw threaded engagement with the bolt so that the bolt can be rotated by means of the nut and above a selected torque the nut will break out.

Abstract: Fastener (1) includes a head (2) and a body (3). The head (2) has a transverse stop (5) able to bear on the first piece (23). The body (3) has a first spacer (10) and a second spacer (11), coaxial and disposed in line with each other in an axial direction. The first spacer (10), adjacent to the head (2), has a diameter greater than that of the second spacer (11) which extends starting from the first spacer (10), on the opposite side from the head (2). Each of the spacers (10, 11) has at least one lug (13; 18).

Abstract: For assembling at least two parts of an object with one another, a bolt having a thread is introduced into the parts, a washer is placed on a free end of the bolt, a nut is threadingly connected to the free end of the bolt so as to abut against the washer, a power tool is placed so as to turn the nut by a rotatable element of the power tool connected to the nut to tighten or loosen the bolt and to apply a non-rotatable element of the power tool to the washer to absorb reaction force and the body of the washer is provided with a breaking point such that when the nut is turned and turns the bolt, the washer stops the bolt from turning and thereby the nut creates a pull on the bolt which elongates the bolt in an axial direction and applies to the body of the washer an axial force which breaks a portion of the body of the washer and allows a portion of the body of the washer to be pulled axially when the bolt elongates.

Abstract: A novel fastener comprises a head having a recess for receiving a rotary driver, a shank having knurls defined by generally helical grooves and intersecting generally annular grooves, wherein a plurality of the knurls include a lateral cutting edge, and a generally pointed tip. Another novel fastener comprises a head having a recess for receiving a rotary driver, a shank having a predetermined diameter small enough so that the head will break away from said shank upon application of a predetermined torque, and said shank having knurls defined by generally helical grooves and intersecting generally annular grooves.

Abstract: A tension control bolt includes a shank, the shank including a threaded section and a breakaway section, and a bolt head, the bolt head constructed with a wrenching section and a flange section intermediate the wrenching section and the shank, the flange section having a generally circular bearing section, the diameter of the bearing section exceeding the distance between opposed flat wrenching surfaces of the wrenching section.

Abstract: A sealing assembly designed to co-operate with a screw provided with a tightening slot by being mounted therein in such a manner that once said assembly is sealed the tightening slot is hidden in a manner that is not reversible except by destroying the seal, and further comprising a breakable drive suitable when the sealing assembly is subjected to a tightening action, for driving the screw in a tightening direction inside a receptacle provided for this purpose and for breaking once the screw becomes blocked, so as to prevent any loosening action being applied via the breakable drive.

Abstract: A torque-limiting bolt-and-nut assembly is provided for actuating a pipe-pressing member in order to secure two pipe ends together. The bolt includes a threaded shank, a secondary drive head, and a shearable drive head designed to be sheared-off by a torque exceeding a predetermined value. A recess is formed between the shearable drive head and the second drive head. The nut is mounted on the shearable drive head and is configured for transmitting torque to the shearable drive head from a manual tool. A nut includes a connection structure extending into the recess for resisting dislodgement of the nut from the bolt. The shearable drive head has at least four sides, all of the sides being of equal length, and the number of the sides being an even number.

Abstract: A concrete embedding anchor includes. An anchor including an anchor body having a head at one end of the shank and a stopper at the other end, a fitment concentrically mounted to said head and having an external thread and easy breaking portion formed on the round bar portion thereof, and a hemispherical shell-shaped former fitted with the middle portion of said anchor shank. A retainer is secured to the concrete form in advance, said anchor fitment is inserted into and screwed up to said retainer, said anchor is combined with the concrete form, then concrete is poured, and said concrete form is taken away after the concrete has hardened.

Abstract: A security seal assembly is designed to provide detection of tampering with or the removal of a wheel lug nut, particularly on a truck tire. The Security Seal is designed as an indicative seal rather than theft seal. When the seal is fitted onto the wheel lug nut, it prohibits access to the nut unless the cover is broken.

Abstract: A fastening position adjustable bolt is provided which includes a bolt body and a cylindrically shaped collar bolt. The bolt body has a head, a shank, and first male threads formed on a lower outer peripheral surface of the shank, and the collar bolt has second male threads formed on an upper outer peripheral surface thereof. An engaging portion engages the shank of the bolt body with the collar bolt. The engaging portion is disposed between the head of the bolt body and a position on the shank at which the first male threads are formed, and the engaging portion is adapted to release engagement between the collar bolt and the shank of the bolt body upon application of a torque having at least a predetermined value.

Abstract: The preferred embodiment of a double ended fastening system includes a first segment for engaging a component and a second threaded segment for engaging a nut. In another aspect of the present invention, the component has a stud receiving portion made of a polymer or soft metal. A further aspect of the present invention provides a self-drilling and self-tapping feature on the stud.

Abstract: The invention comprises a roof bolt and nut in screw threaded engagement, said bolt comprising a shaft for insertion in a hole drilled in a mine roof and a threaded portion engaged by the nut whereby the bolt may be rotated. The nut is offset with respect to the longitudinal axis of the shaft of the bolt so that when the bolt is rotated by means of the nut, the bolt is caused to describe a circle of greater diameter than its own diameter, the amount of said offset being from about 0.015 to about 0.50 inches. Preferably the offset is from about 0.02 to about 0.25 inches.

Abstract: Breakaway web stops are provided which are employed in seat belt systems for restraining an occupant. In one such seat belt system, the seat belt webbing passes diagonally across the torso of the occupant, through a latch plate, and then across the lap of the occupant. To ensure that the latch plate stays in the correct position, web stops are placed on the seat belt webbing both above and below the correct position of the latch plate, allowing the latch plate to freely move between the two web stops, but not permitting it to move outside this range. In an accident, the breakaway web stop below the latch plate is configured to separate from the seat belt webbing, permitting the tension from the torso portion of the seat belt webbing to transfer to the lap portion of the seat belt webbing, providing additional and safety-enhancing restraint to the occupant, and, in particular, to the occupant's legs and lower body.

Abstract: A fastener having a tamper-evident sleeve thereon. The fastener has a shank and a double-headed driving portion that is integrally formed with the shank. The double-headed portion includes an outer head for driving the fastener into a work piece or nut and an inner head for removing the fastener from an assembly. The sleeve is on the inner head and prevents a tool from being engaged with the sleeve for removal of the fastener without there resulting some indication that someone has removed or tried to remove the fastener.

Abstract: A break-away apparatus for electrical and optical connectors (12) includes front and rear fittings (30, 32) with peripheries that have pairs of aligned fastener-receiving holes, and a plurality of fasteners (100) that each lies in a pair of holes and holds the peripheries of the fittings together. Each fastener is a screw with a shank having a threaded front end that engages threads in the hole of the front fitting, and includes a screw head (214) at the rear of the shank which lies against a rearwardly-facing shoulder (172) on the rear fitting, to thereby prevent fitting separation. A bore (142) extends along the axis of the shank, and a rear end portion of the shank has a groove (182), resulting in a break-away portion of the fastener that has a ring-shaped cross-section. The ring-shaped coss-section permits tightening of the screw but results in the screw breaking when a predetermined force is applied to allow separation of the fittings.

Abstract: A robust rigid block forming a fastener and tamper evident seal attaches a cover to a tote bin. The seal is formed partially into a C-shaped locking device for insertion into aligned bores in the tote bin cover and bin. The C-shaped device is inserted to an insertion position and then displaced to a locking position with the legs of the device overlying the cover and bin members at the bores fastening the cover to the bin and capable of withstanding high shock loads. A locking element connected to the device by a frangible web has a camming surface that engages an edge of the cover for camming the device during insertion of the element in the bores to the insertion position at which time the web is fractured. The element has a flange plate attached to the element body by a weak web for selective removal of the plate. A resilient tang is attached to the element for engaging a mating locking recess in the body for locking the element to the device and to the bin and cover in the insertion position.

Abstract: A coupling assembly for use in connecting fluid lines having a unitary female body and a male coupling portion. The female body includes at least two passageways having frangible diaphragms. The male coupling portion includes at least two male coupling halves having frangible diaphragms. Cutting devices are positioned in the passageways of the female body. As the male coupling portion is moved toward the female body by a bracket and fastening device, the diaphragms are ruptured to allow fluid flow between the lines.

Abstract: The plug (1) comprises two coaxial parts (2, 3) separated by a fracture initiating line (4). A respective print (6, 7) is provided on each part and is coaxial with the other print. The first part (1) permits the screwing of the second part (3) which is provided with a screw thread (5) in an implant to which it must remain fixed after fracture of the two parts on the line (4), when a predetermined fracture torque is exceeded. The print (7) of the second part (3) permits a subsequent unscrewing, if necessary, for disassembling the instrumentation, which constitutes an essential advantage of this plug. Further, the clamping can be achieved with high precision in conformity with the wishes of the manufacturer, since the fracture torque can be adjusted to the intended value by machining the fracture intiating line (4) in a precise manner.

Abstract: A medical implant set screw having a base joined to a head by a breakaway region. The set screw has a longitudinally and axially extending bore that passes through the head and into the base. The bore has a stepdown within the base so as to produce a first circumferential edge. The base breaks away from the head at a predetermined torque during installation so as to expose an upper surface. The portion of the bore in the base intersecting with the upper surface forms a second edge that is spaced above the edge formed by the step and which has a somewhat greater diameter than the edge formed by the step. The two edges of the bore are sized, positioned and spaced so as to allow an easy-out to simultaneously engage both to improve gripping by the easy-out of the base during removal thereof.

Abstract: A locking device is disclosed for interlocking two members having aligned openings extending therethrough. The device includes a hollow cap and a pin with an enlarged head at one end and a nose at the opposite end. The pin is insertable through the aligned openings of the members, with its nose received in interlocked engagement within the cap, and with the two members captured between the cap and the enlarged head of the pin. A frangible portion of the pin is severable in response to relative rotation between its nose and enlarged head to thereby destructively disassemble the locking device.

Abstract: A fastener having a tamper-evident sleeve thereon. The fastener has a shank and a double-headed driving portion that is integrally formed with the shank. The double-headed portion includes an outer head for driving the fastener into a work piece or nut and an inner head for removing the fastener from an assembly. The sleeve is on the inner head and prevents a tool from being engaged with the sleeve for removal of the fastener without there resulting some indication that someone has removed or tried to remove the fastener.

Abstract: The preferred embodiment of a double ended stud fastening system includes a first segment for engaging a plastic component, a second threaded segment for engaging a nut and a lateral projection disposed between the segments. In another aspect of the present invention, the first segment is threaded and the lateral projection is a flange.

Abstract: The present invention provides a novel fastener having a tamper indicating tool engaging drive head. The fastener has a shank including a threaded shank portion. The fastener also has a double-headed driving portion that is integrally formed with the shank. The double-headed portion includes an outer head for driving the fastener into a work piece or nut and an inner head for removing the fastener from an assembly. The inner head is joined to the outer head such that the inner head is positioned between the outer head and the shank. Extending portions extend from tool engaging surfaces of the inner head. In use, the fastener is driven into an assembly via a proper tool that engages with the outer head. The outer head shears off the fastener when the desired torque is achieved, leaving only the shank within the assembly and the inner head exposed.

Abstract: A spinal implant assembly is provided which has a stabilizer rod clamped into position within an anchor by means of a sliding closure member including a mating set screw or hook. The exterior faces of the anchor are contoured to optimize interface in the surgical setting. The anchor includes a U-shaped channel having multiple undercut surfaces such as grooves, which mate with flange like projections or “dovetails” of a closure member which is slid in a direction corresponding to the longitudinal axis of the rod. The closure member has on either side a flange mating with opposing recesses formed at the top of the U-shaped channel so as to lock the closure member in place. The set screw has an external hex head for tightening, and a plurality of radically extending prongs which are undercut and which mate with the recesses in the top of the U-shaped channel of the anchor. The hex head sheers at a necked area above the radial collar to provide for a flush surface relative to the closure member.

Abstract: A nut for use with an elongated rod having one end anchored by a hardened resin grouting mix in a drill hole in a mine roof or other such rock formation. The nut has a body portion with a threaded bore through which the rod is advanced and a dome-shaped wall surrounding one end of the bore in radially outwardly spaced relation and an annular lip defining an opening in coaxial, axially spaced relation to the one end of the bore. A metal disc, either solid or with a central opening of smaller diameter than the bore, is positioned in covering relation to the bore and surrounded by the dome-shaped wall. As the rod is advanced through the nut, the disc is moved into contact about its entire periphery with the inside of the dome-shaped wall and rotation of the nut is transmitted to the rod to mix the resin components within the drill hole.

Abstract: Bioresorbable pin systems useful for the reduction of bone fragments and for fixing bioresorbable membranes to a bone are provided, particularly pins having a detachable handle and a pre-fabricated hole in the handle through which a tether may be threaded to facilitate removal of the handle once it has been detached from the pin.

Abstract: An insert for thread repair having an interior thread and a specially formed exterior thread which both precludes upheaval between sides of the cracked material on opposite sides of the crack and draws the crack together, radially inward towards the center of the insert. The insert may include a driving head, either solid or having a central hollow and may include a frangible neck to dissociate the head from the insert.

Abstract: A flexible joint comprises: first cylindrical bodies comprising a pair of spherical ring members; a second cylindrical body comprising a sleeve relatively movably inserted in the first cylindrical bodies from an axial direction X of the second cylindrical body; third cylindrical bodies comprising a pair of casing tubes which are fitted around outer peripheral surfaces of the first cylindrical bodies and are provided with mutually slidable spherical inner peripheral surfaces, the casings being formed at their opposite ends with connecting portions, and being provided at their outer peripheral surfaces of large diameter portions with projections having through holes; and rods capable of being inserted into the through holes formed in the outer peripheral surfaces of the large diameter portions, each of the rods being provided and fixed between the projections of the pair of third cylindrical bodies for restricting the telescopic movement of the tube joint, wherein the rods comprise a pair of rods connected to e

Abstract: A casing slip joint has been invented that has a first tubular casing member disposed around and releasably connected to a second casing member, the second casing member within and surrounded by the first casing member. Self-destructive shear screws according to the present invention releasably hold the first casing member to the second casing member. In one aspect, a shear screw according to this invention has an outer shear screw with a central recess and an inner member therein. In one aspect the outer shear screw is made of one metal and the inner screw is made of another so that contact by a well fluid sets up a galvanic cell that produces stress corrosion cracking in the outer shear screw that weakens it and/or destroys it. The propagation of such cracks is facilitated by placing one or more notches or recesses in the body of the components.

Abstract: An improved set screw, for use in an osteosynthesis apparatus to secure and fix a spinal rod in the bore of the head of a bone screw, hook, connector or the like from translational or rotational motion, which comprises a head of hexagonal external cross-section and a lower portion having a threaded outer surface. The lower threaded portion includes a feature which facilitates subsequent removal of the lower threaded portion from the threaded bore in which it is secured. In a first embodiment, the feature facilitating removal, comprises a bore which extends completely through the screw, from top to bottom. The bore may be cylindrical and adapted to receive an easy out tool for removal of the lower threaded portion, or of a geometry which corresponds to the shape of an allen type wrench which may be inserted in the section of the bore extending into the lower threaded portion of the screw for use in removal of the lower threaded portion.

Abstract: A gauge for measuring bone thickness includes an elongated pin for insertion into a bore through a bone section. The pin has a length sufficient to span the entire bone section with a distal tip protruding therefrom. The pin further has a length measurement indicator disposed along an outer surface, such as a series of colored bands or indicia, the visualization of which communicates bone thickness. In a particular embodiment a protrusion extending away from the pin's outer surface is provided to retain the pin within the bore. A cannula may be provided for facilitating the introduction of the pin into the bone section. Methods are also described for measuring bone thickness and for contouring bone.

Abstract: The plug (1) comprises two coaxial parts (2, 3) separated by a fracture initiating line (4). A respective print (6, 7) is provided on each part and is coaxial with the other print. The first part (1) permits the screwing of the second part (3) which is provided with a screw thread (5) in an implant to which it must remain fixed after fracture of the two parts on the line (4), when a predetermined fracture torque is exceeded. The print (7) of the second part (3) permits a subsequent unscrewing, if necessary, for disassembling the instrumentation, which constitutes an essential advantage of this plug. Further, the clamping can be achieved with high precision in conformity with the wishes of the manufacturer, since the fracture torque can be adjusted to the intended value by machining the fracture intiating line (4) in a precise manner.

Abstract: The present invention relates to a tear-off cap or shearable screw (1) comprising a plurality of thread portions (3) and a cap portion (5) connected with the thread portions (3) via a first predetermined breaking point (7), wherein further predetermined breaking points (9) in the form of cross-section tapering are provided between the thread portions (3). The present invention distinguishes itself by the fact that the tear-off torques both increase and decrease from the most remote thread portion towards the cap portion (5), this forming at least one stepped predetermined breaking point (13).

Abstract: After a bolt (3) and a double-structured nut (6) are fastened to each other, it is not possible to unfasten the bolt (3) and nut (6), because a predetermined part of the nut (6) is designed to break when subjected to a predetermined torque necessary for fastening the nut (6), and thereby permitting the remaining part of the nut (6) to remain fastened securely to the bolt (3) after the fastening operation of the bolt (3) and nut (6) is performed. The nut (6) double-structure including a cylindrical cover member (7) may alternatively be utilized for a similar double-structured bolt head (42) having a protective cover (43).

Abstract: A device used to indicate whether a predetermined compressive load has been applied to the device. The device is formed to receive an anchor member upon which a tensioning force is to be applied in conjunction with loading the device. The device itself has an upper press that has an aperture formed to receive the anchor member and also has means for manipulating a washer. The device also has a lower die with an aperture formed to receive the anchor member. The lower die is formed so as to be able to work in conjunction with the upper press when the upper press and lower die are aligned and moved towards each other. The lower die also has means for manipulating the washer. The means for manipulating the washer are also formed to cooperate with the means for manipulating the washer on the upper press. The device also has a washer that lies between the upper press and the lower die.

Abstract: The invention relates to a plastic fastening element for fitting onto a stud with a base body (1) having a socket (2) with at least one orifice (3) for the stud, with a collar (4) which at least partially surrounds the orifice (3) and is formed integrally with the base body (1), with a perforated disc (5) which has a hole (6) orientated substantially coaxially to the orifice (3) and is molded on the collar via at least one set breaking point connection (7) at a distance from the base body (1) prior to fitting of the fastening element. A secure and reliable seal is achieved.

Abstract: A method and apparatus for repairing a casting in a cold metal repair process includes a plurality of drilling fixtures which facilitate the creation of one or more lock receiving recesses positioned generally transverse to the casting crack. The lock receiving recesses are formed of a single sized circular bore combination having alternating double and single circular portions to maximize strength. A plurality of correspondingly configured metal locks are inserted into the lock receiving recesses to provide transverse metal locks drawing the casting portions on each side of the crack together. A plurality of threaded bores are formed along the remainder of the casting crack in overlapping spacing which receive a corresponding plurality of stitching pins. The stitching pins each define threaded shaft portions having pointed ends and undersized major pitch diameter threads adjacent the pointed ends.

Abstract: A tapered shear stop has rigid tapered shear stud and tapered polyurethane overing that both have rounded outer surfaces. The tapered shear stop is mounted in a bracket to withstand steady state and impacting loads from a boom and to shear through a reduced section in the stud that is located next to the bracket to prevent bending or transmitting other damage to the bracket when excessive loads are encountered. Differently sized shear stops, or more than one shear stop can be used to protect associated mechanical structure from damage.

Abstract: A nail having a nail head with a top surface having a plurality of protuberances formed thereon, a nail body extending from a bottom surface of the nail head, a nail tip formed at an end of the nail body opposite the nail head, and a ring portion formed between the nail head and the nail body. The ring portion has a plurality of indentations formed thereon so as to allow separation of the nail head from the nail body upon a twisting force applied to the plurality of protuberances. The nail tip has a plurality of sliced sections formed thereon. The sliced sections have differing surface areas. The sliced sections have a generally diamond-shaped configuration. A plurality of slanting ribs extend along a length of the nail body at an acute angle relative to a longitudinal axis of the nail body.

Abstract: In a break-away coupling for a highway and road side appurtenance, a controlled breaking region is provided which has at least two axial spaced necked-down portions co-axially arranged between the axial ends of the coupling which are configured to be attached both to the appurtenance, at one end, and to the support base, at the other end. Each necked-down portion essentially consists of two axially aligned conical portions inverted one in relation to the other and generally joined at their apices to form a generally hour-glass configuration having a region of minimal cross section at an inflection point having a gradually curved annular concave surface defining a radius of curvature. Each of the two necked-down portion has different radii of curvature that at respective inflection points to provide preferred failure modes as a function of the position and direction of impact of a force on the appurtenance.

Abstract: An improved set screw with a break off head for use in an osteosynthesis apparatus. The set screw comprising a head or stem preferably having a hexagonal external cross-section, a lower portion having a thread extending around an outer surface thereof and a shank connecting the head to the threaded lower portion. An outer diameter of the shank is equal to a minor diameter of the threaded lower portion, i.e. the outer diameter of the threaded lower portion at the base of the thread. A bore extends into the set screw from an upper surface thereof. The bore has a first bore section and a second bore section wherein the second bore section has a reduced diameter relative to the first bore section and is separated from the first bore section by an internal shoulder. The internal shoulder extends into the bore below an upper end of the thread.