Abstract: Provided is an expansion-type anchor with excellent pull-out strength. The anchor comprises an anchor body 1 that has an expansion section 3 split by an inner slit 2, and a sleeve 9 to enclose and hold the expansion section 3 of the anchor body 1. The sleeve 9 is split into a plurality of follower expansion sections by an outer main slit 10 and an outer auxiliary slit 11. A group of balls 4 is disposed inside the anchor body 1, and the expansion section 3 expands into a tapered shape when the group of balls 4 is pressed by an expansion bolt 6. When a pull-out force is applied to the anchor body 1, the sleeve 9 does not retract and deforms by expanding after the retraction of the anchor body 1. As a result, the anchor body 1 is prevented from retracting by way of the sleeve 9 being sandwiched between a prepared hole 13 and the expansion section 3.

Abstract: A fastener suitable for temporarily or permanently connecting one object to another, for example a form to concrete. The fastener includes a nail having a guide wire bonded thereto, with the guide wire including a segment that extends outwardly past the tip of the nail, which facilitates insertion into a hole predrilled in the objects. The bond between the nail and wire is adapted to be broken in at least one area of connection when the fastener is driven into the predrilled hole.

Abstract: A fastener anchoring system is disclosed. The fastener anchoring system provides for an anchor with first-direction external threading, while a bore through the anchor provides second-direction internal threading. Thus, the anchor is screwed/secured to a substrate in the first direction and unscrewed in the second direction, while the fastener being anchored in the bore is screwed/secured in the second direction and unscrewed in the first direction. As a result, unscrewing the fastener does not urge the unscrewing of the anchor from the substrate.

Abstract: An attachment device for attaching at least one element, in particular lines such as cables, pipes, hoses and the like, to a component section. The attachment device comprises a retaining section for encompassing, at least in some sections, at least one such element, and comprising a flange section for resting against the component section. Spring sections of a hollow engagement body, which spring sections are acting in the radial direction, are blocked as a result of the insertion of a securing pin into the interior of the engagement body, and can thus no longer be moved radially inwards towards each other. A method for installing such an attachment device.

Abstract: Adapter device for ceramic cutting machines (2) that comprises an adapter plug (1) of the hole (8) of the tool holder (7) of a ceramic cutting machine (2), the plug (1) comprising a hollow cylindrical shape with a stop (12) that performs an axial fixation in a direction of the plug (1) in the hole (8) of a tool holder (7) of a ceramic cutting machine (2) and; a longitudinal slot (13) that leaves open the inner hollow space of the plug (1) in its entire length, said longitudinal slot (13) comprising a narrower segment in the part of the plug (1) that is nearest the end (21) comprising the stop (12), and a wider segment in the part of the plug (1) that is near the end (22) of the plug (1) opposite the stop (12).

Abstract: A fastening device for furniture fittings on furniture parts which includes at least one dowel core that can be inserted into a hole of a furniture part. The dowel core can be arranged inside a dowel sleeve, and an actuating device moves the dowel sleeve relative to the dowel core, so that the dowel sleeve spreads on the dowel core. The dowel core and the dowel sleeve have at least two, preferably more, corresponding inclined surfaces that are offset in the axial direction, so that if the dowel sleeve is moved relative to the dowel core, the dowel sleeve spreads substantially evenly at two, preferably more, axially offset locations.

Abstract: An anchor stud includes a stud portion including a body portion having a first end that extends to a second end though an intermediate portion. A wedge member is operatively coupled to the second end of the stud portion. The wedge member includes a body having a generally frustoconical profile and is formed from a material having a Vickers hardness greater than about 220 HV. A sleeve element is positioned on the stud portion at the second end adjacent the wedge member. The sleeve element is formed from a material having a Vickers hardness greater than about 220 HV.

Abstract: A wedge-type anchor assembly, capable of meeting cracked concrete testing standards, comprises an anchor bolt component and a substantially C-shaped expansion sleeve component annularly disposed about the anchor bolt component. A plurality of annular grooves, threads, or teeth are disposed only about the forward end portion of the expansion sleeve component, as opposed to throughout the entire axial length thereof, so that when the anchor bolt component is moved axially through the expansion sleeve component, the maximum interference area (M.I.A.) and maximum interference volume (M.I.V.) can be generated between the anchor bolt component and the expansion sleeve component in a controlled and predictable manner, as well as between the expansion sleeve component and the internal peripheral side wall portions of a concrete substrate or substructure can be generated so as to enhance pull-out resistance and reliability of the anchor assembly within the concrete substructure or substrate.

Abstract: An anchor stud includes a stud portion including a body portion having a first end that extends to a second end though an intermediate portion. A wedge member is operatively coupled to the second end of the stud portion. The wedge member includes a body having a generally frustoconical profile and is formed from a material having a Vickers hardness of between about 218 HV and about 290 HV. A sleeve element is positioned on the stud portion at the second end adjacent the wedge member. The sleeve element is formed from a material having a Vickers hardness of between about 218 HV and about 290 HV.

Abstract: An expansible anchor assembly includes an expansion sleeve and an anchor bolt plugging and expanding the expansion sleeve. The expansion sleeve includes a first end, a second end, an expansible member adjacent to the second end that is divided into expansible segments by slits, and a bore defined in the expansion sleeve for communicating the first end with the second end. A groove is annularly formed on the expansion sleeve, and a distance from the groove to the second end equals to ¼˜? times a length of the expansion sleeve for preventing an over length of the slits, which is beneficial to the manufacture. During expansion, the expansible segments are completely expanded when the expansible member is subjected to a thrust from the anchor bolt to promote the anchoring force and avoid damaging a working wall.

Abstract: The present invention relates to an anchor bolt and more specifically pertains to a post-installed anchor that is securely anchored to, for example, an existing concrete floor. The post-installed anchor has a sleeve fit on a bolt body and a fixation member arranged on an edge of the bolt body and screwed to a threaded end of the bolt body. The fixation member has an internal threaded end and an expansion end. The expansion end is divided into four expansion pieces by slits. The expansion pieces are arranged to face a head of the bolt body and are slightly widened toward the head of the bolt body. One end of the sleeve forms a tapered face. After insertion of the post-installed anchor into a pilot hole (installation hole) bored in the concrete floor, as the bolt body rotates, the fixation member screwed to the bolt body moves toward the sleeve. This movement causes the expansion end of the fixation member to ride on the tapered face of the sleeve and to be pressed open and extended outward.

Abstract: An expansion anchor comprising a tubular body, which extends along a longitudinal axis and displays a deformable end portion on which there are obtained longitudinal slots which divide the end portion itself into a series of anchoring fins, and an expansion nut, which is partially engaged onto said end portion and is adapted to be displaced by a screw so as to radially expand said anchoring fins outwards; each anchoring fin being shaped so as to display an annular ridge on its end and two protruding side teeth, which are arranged on the side edge of said anchoring fin at the two ends of the ridge; each anchoring fin further displaying an external friction surface provided with a plurality of annular notches or cavities coaxial to the longitudinal axis.

Abstract: A wedge-type anchor assembly, capable of meeting cracked concrete testing standards, comprises an anchor bolt component and a substantially C-shaped expansion sleeve component annularly disposed about the anchor bolt component. A plurality of annular grooves, threads, or teeth are disposed only about the forward end portion of the expansion sleeve component, as opposed to throughout the entire axial length thereof, so that when the anchor bolt component is moved axially through the expansion sleeve component, the maximum interference area (M.I.A.) and maximum interference volume (M.I.V.) can be generated between the anchor bolt component and the expansion sleeve component in a controlled and predictable manner, as well as between the expansion sleeve component and the internal peripheral side wall portions of a concrete substrate or substructure can be generated so as to enhance pull-out resistance and reliability of the anchor assembly within the concrete substructure or substrate.

Abstract: A wedge-type anchor assembly, capable of meeting cracked concrete testing standards, comprises an anchor bolt component and a substantially C-shaped expansion sleeve component annularly disposed about the anchor bolt component. A plurality of annular grooves, threads, or teeth are disposed only about the forward end portion of the expansion sleeve component, as opposed to throughout the entire axial length thereof, so that when the anchor bolt component is moved axially through the expansion sleeve component, the maximum interference area (M.I.A.) and maximum interference volume (M.I.V.) can be generated between the anchor bolt component and the expansion sleeve component in a controlled and predictable manner, as well as between the expansion sleeve component and the internal peripheral side wall portions of a concrete substrate or substructure can be generated so as to enhance pull-out resistance and reliability of the anchor assembly within the concrete substructure or substrate.

Abstract: An anchoring element for being mounted on a shaft (52; 62; 72; 92) of a fastening element (51; 61; 71; 91) has a through-opening for the shaft (52; 62; 72; 92) and a strip extending around the through-opening (12; 32; 82) over an angular region of more than 360°.

Abstract: A rock bolt anchor includes a top portion permanently fixed to a bottom portion. The top portion carries a package of resin. A spring-loaded mechanism pressurizes the package and forces the resin out when the package is lanced. The bottom portion main body carries a pair of opposed outer shells in a dovetail joint on opposed tapers. The annulus adjacent to the rock bolt anchor is sealed by top and bottom bulkheads. The bottom portion is threaded onto a rock bolt. A hollow and ported lance is threaded onto the exposed end of the rock bolt. The combination is inserted into a drilled hole and the rock bolt rotated. The lance rises and pierces the package releasing into the sealed annulus. Continued rotation of the rock bolt, forces the main body down and the outer shells up the tapers compressing them against the wall of the drilled hole.

Abstract: An anchor is provided that is inserted into a bore in a cementious member, the bore having a side wall. A tensioning head is connected to the leading end of the stem and when the stem is moved the tensioning head moves with the stem. The outer surface of the tensioning head flares generally outwardly from the trailing end to the leading end of the tensioning head. The anchor also has an expansion sleeve, and the stem can move longitudinally through the expansion sleeve when the expansion sleeve is held in a fixed position, and the tensioning head pushes upon the expansion sleeve, causing it to flare outwardly. The expansion sleeve is provided with first and second grooves that assist the expansion sleeve in expanding without splitting.

Abstract: An undercut anchor element comprising a shank of an anchor bolt. The shank passes through a base part, which is provided for effecting an anchoring, passes through a spacer sleeve, and at the end thereof is provided with a tightening head. The tightening head can be pulled inside the base part, which is subdivided into anchoring segments by slots provided over a portion of the length of the base part. The slots lead from the front free end of the base part up and into the area of an encircling groove. The anchoring segments have the outer shape of two truncated cones which coincide with their ends that have a smaller diameter. The truncated cone that is located in front in a direction of mounting has an obtuse cone angle of greater than 150° and the adjoining truncated cone has an acute cone angle of less than 30°.

Abstract: A joining assembly for joining a pair of structural members, comprises a bolt having a thread and a nut-like blind rivet adapted to be inserted into mounting holes of the structural members and to be threadingly engaged to each other. One of the mounting holes is made of resiliently deformable material and comprises a base member including a bore for receiving the thread of the bolt and having an outside provided with a plurality of threads which are similar in number to the corners of the polygonal mounting hole, such that when the bolt is threadingly engaged into the bore of the blind rivet the base member is folded whereby the threads have parts of their flanks pressed against one of the structural members.

Abstract: An adjusting element for fastening a headlight arrangement on a vehicle. The adjusting element has a nut element and a screw element, the screw element being screwed into the nut element. An opening is formed at a vehicle-body-side supporting plate for the nut element. The nut element is formed by an expansion nut which can be inserted into the opening, can be adjusted and has an eccentrically constructed receiving groove, so that, in the insertion direction and transversely thereto, the opening has a larger measurement than the inside diameter of the receiving groove and that, as a result of the screwing of the screw element into the positioned expansion nut, the latter is fixed on the supporting plate.

Abstract: A releasable fastening device that includes a rivet (3) that can be inserted in through openings (5, 6) of components (1, 2) that are to be mounted. The rivet (3) is provided with a projection at one end and with spreadable expansion elements (4) at its other end. A threaded bolt (8) is axially pushed into an internal counter-thread of the rivet (3) to spread the expansion elements (4). When the fastening device is assembled, the walls of the components (1, 2) or of an intermediate element (7) engage radial recesses on the circumference of the rivet (3) to hold the components securely. Bolt (8) can be unscrewed from the rivet (3) to facilitate disassembly.

Abstract: A mounting element used in furniture building which is inserted into a bore of a furniture element and fixed in place therein. The mounting element includes a fastening sleeve and a connecting pin wherein the fastening sleeve is divided into deflectable holding springs and is inserted into the bore of the furniture element. The holding springs have tooth elements on an exterior and enclose a centered receptacle for the connecting pin. The connecting pin has a fastening receptacle or threaded receptacle and is connected in one piece with the fastening sleeve by gates which act as predetermined breaking points. The connecting pin is secured by the gates in a prepared position, ready to be driven. A connecting pin produced separately from the fastening sleeve is secured by partially inserting the connecting pin into the receptacle of the fastening sleeve in a prepared position, ready to be driven.

Abstract: A fastener includes an upper retaining portion, a body and a pin. The upper retaining portion has an aperture. The body has first and second side portions. The first and second side portions have first and second ends. The first ends of the first and second side portions are coupled to a surface of the upper retaining portion on opposite sides of the aperture and extending in a direction away from the surface of the upper retaining portion. The first and second side portions having a plurality of branch portions coupled to an outer surface of the respective first and second side portions. The pin has a top and an insertion portion. The insertion portion is adapted to be inserted through the aperture of the upper retaining portion, thereby expanding the body in outward directions.

Abstract: An anchoring device (10) comprises a resilient sleeve (16) for receiving an elongate member, such as a bolt (18), and first and second stoppers (20,21) for location on the bolt at respective ends of the sleeve. Movement of the stoppers (20,21) towards one another causes the sleeve (16) to expand radially. The inner first stopper (20) may engage one of the bolt head (22) and nut (24) to resist relative rotation thereof. Alternatively, the inner first stopper may be threaded.

Abstract: A dowel for securing objects to construction elements, in particular gypsum plaster boards, has an expanding dowel body with an inner bore into which a fastening crew can be screwed. In an insertion front area, the dowel body is subdivided into at least two head segments buy a slot that starts at its front end. The dowel body also has a continuous necking in the front area of its outer surface. The dowel body further has at its rear end opposite its front end a stopping plate that extends transversely to the dowel longitudinal axis.

Abstract: An expandable anchor assembly is provided for anchoring the threaded end portion of an elongated roof bolt in a borehole. The anchoring assembly includes a hollow outer sleeve in the form of a plurality of symmetrically arranged, longitudinal segmented wall portions with exterior gripping teeth and an inner expander sleeve in the form of a corresponding plurality of longitudinal wall portions symmetrically arranged about a central axis to define an inner threaded cylindrical section. The inner sleeve is captured within and moveable axially relative to the outer sleeve. As the threaded end portion of the elongated bolt is inserted into the inner threaded cylindrical section of the inner sleeve from the trailing end to the leading end thereof, the inner sleeve expands over and clamps around the threaded end portion of the elongated bolt.

Abstract: An expansion dowel including an expansion sleeve one end portion (4) of which receives a load and an opposite portion of which has an expansion region divided into expansion tabs by a plurality of longitudinal slots (7) extending toward a leading end of the expansion sleeve (2), with the expansion tabs (6) being connected with the expansion sleeve (2) by a first ductile joint (5) and having an annular collar (8) interrupted by the longitudinal slots (7), and an expansion member (13) displaceable in an axial through-bore (3) of the expansion sleeve (2) from an initial position to an end position upon expansion of the expansion region of the expansion sleeve (2), with the expansion tabs (6) projecting beyond the annular collar (8) and integrally connected with a distance segment (10) of the expansion sleeve (2), which distance segment collapses radially inward upon expansion of the expansion tabs.

Abstract: A rock bolt shell and cone. An expansible shell having a cylindrical outer surface and raised ridges in relief on the exterior of the shell. One or more ridges are located along a curve non-congruent with a circumferential circle of the cylinder. In a disclosed embodiment, each ridge lies along a helix of the cylinder and ridges are paired such that the helix of a first extends in one rotational direction while the curve of a second of the pair extends in the other rotational direction. Each helix forms an angle of forty-five degrees with a center line of the cylinder. Ridges intersect such that "V"-shaped projections extend along the outside of the shell. The vertices of certain of the projections project a radially maximum amount while each of the legs of the "V" taper radially inwardly toward the cylindrical surface as the leg extends away from the vertex. The cone, threaded for installation on a bolt rod has one or more axial indentations to improve grout flow about an installed bolt.

Abstract: A fixing element of metal, in particular for fixing facing panels, has a slotted expansible sleeve arranged to be expanded into an undercut of a drilled hole and having an inner bore with a slotted part, and an expander element effecting an expansion of the expansible sleeve and arranged to clamp an article to a facing panel. The expansible sleeve has a plurality of inwardly bent expansible segments having a leading end face and an outer surface and provided with a circumfernetial enlargement arranged on the outer surface of the expansible segment in the region of the leading end face. The expander element is formed as a blind rivet with a rivet shank and a clench head which is drawn with the rivet shank into the slotted part of the inner bore of the expansible sleeve and riveted.

Abstract: An impact-type expansible plug for anchoring in a cylindrical drilled hole of a concrete part and the like has an expansion sleeve provided with at least one longitudinal slot and expandable in a drilled hole, and also has an expansion sleeve with a conically narrowing internal bore, and an expansion mandrel drivable into the conically narrowing internal bore of the expansion sleeve. The expansion sleeve has a forward end provided with an annular collar having a radially directed circumferential cutting edge, and also has a portion tapering toward the annular collar.

Abstract: The retention value of a screw previously inserted into a wooden railroad tie is increased by an axially extending sleeve ( 20 ) having an external thread ( 24 ) and an internal thread (25). The thread revolutions of the internal thread (25) are offset axially by half (h) the thread pitch (H) of the external thread (24). Due to this offset of the threads, the screw is positioned in the sleeve so that its threads are located between the external thread revolutions affording a new retention, while the external thread (24) seats within the thread previously formed in the wooden railroad tie by the screw.

Abstract: An axially extending sleeve (1), for use as an anchor secured by grout or a hardenable mass in a blind bore (2a) in a structural component (2), has an outside surface with a radially outwardly projection extending in the axial direction of the sleeve. The sleeve has a closed first end leading in the insertion direction and a trailing second end. The projection extends from the second end in the axial direction toward the first end. An elastic layer (3) is placed over the surface of the structural component containing the bore and a hole (3a) in the elastic layer is aligned with the bore in the component. When the sleeve (1) is inserted into the bore (2a), the projection (1d) forms a passageway through the elastic layer, so that air and excess grout can escape from the bore through the elastic layer.

Abstract: An expansion sealing plug having a frusto-conical plug body with peripheral U-shaped grooves, an expansion member comprising either an inner wedge pin or a spherical member, and a tapered coaxial bore for receiving the expansion member. The inner wedge pin has a greater average outside diameter and the spherical member has a greater maximum outside diameter than the tapered coaxial bore. The plug body and expansion member are proportioned to be readily preassembled such that the expansion member is frictionally retained after partial insertion into the plug body. The unexpanded plug is inserted into a counterbore that is reamed or formed with the same taper angle as the plug body and the expansion member is driven axially into the plug such that the plug body is radially expanded to forcibly engage the counterbore.

Abstract: The nail sustainer of this invention is used to be inserted into a hole formed with a board such as a plaster board, a veneer or a plywood which has poor sustaining force against a nail. The nail sustainer comprises tube means for nail insertion, at least one flow opening for an adhesive agent formed with said tube means, splitting portions formed with said tube means along substantially whole the length of the tube means, and at least one ring-like projection formed to project from a peripheral portion of said tube means.

Abstract: Screw fixing device for a concrete construction element comprising a screw (1) and a sheath (4) of synthetic material intended to be fixed in the concrete. The sheath and the screw possess a trapezoidal thread. Externally, the sheath possesses peripheral anchoring ribs (7) of triangular section, except in its upper part (6). The slope of the flanks (8) of the ribs facing the entry to the sheath is about 30.degree.. The sheath of synthetic material is surrounded by a metal sheath (12) bearing on these flanks (8) but having a play relative to the other flanks (9) of the ribs.

Abstract: A mechanical plug device for sealing pipeline access ports having a small threaded inner surface. The mechanical plug device has opposing inner and outer circular plate members. The rigid plate members each have interiorly tapered circumferential shoulders of generally the same predetermined slope. The inner plate member has an inner surface, an outer surface, a central aperture and a central cavity extending inward from the tapered circumferential shoulder. The outer circular plate member has an inner surface, an outer surface, a central aperture and an outwardly extending structure from the tapered circumferential shoulder for movement into the central cavity of the inner plate member. The device further has an elastomeric radially expandable pre-threaded O-ring structure which has an outer circumferential threaded surface configuration. The O-ring structure has a V-shaped bottom cross-section defining inclined surfaces of a predetermined slope.

Abstract: An expandable mine bolt assembly having a shell and wedge unit threaded upon the shank of an elongated bolt. The shell contains at least one or more leaf sections. The arms of a U-shaped metal strap are joined to the shell and the strap is arranged to pass over the wedge and the distal end of the bolt. At least one arm of the strap is provided with a wrapped section containing folded legs. The distal end of the bolt applies pressure against the strap as the bolt is threaded through the wedge which, in turn, causes the legs of the wrapped section to unfold into holding contact against the wall of a receiving hole thereby preventing the assembly from spinning in the hole as the shell is being expanded by the wedge.

Abstract: A one-piece, malleable iron, expansion shell, and a leaf of such shell, for use in an expansion to be installed in a relatively small (about 1") diameter bore hole with a conventional size (5/8") bolt. The expansion shell, and individual shell leaves have unique features contributing to the effectiveness of the anchor when used either with or without a resin grouting mixture. The slots or spaces between adjacent shell leaves include upper and lower portions, each of constant width, the lower portion being wider than the upper portion, whereby the leaves are narrower in the area where they are bent outwardly from the closed ring at the base than in the area where they are compressionally engaged between the plug and the hole wall. Upper portions of the inner leaf surfaces taper toward the shell axis and the side edges of such surfaces taper toward one another from the upper, free ends of the leaves toward the lower ends.

Abstract: An expansible plug assembly that comprises a fixing bolt, and an expansible sleeve having an expansible portion and an internal thread formed in the expansible portion and engaged with the external thread of the fixing bolt, so that a reliable connection between the fixing bolt and the expansible sleeve is formed.

Abstract: A locking apparatus intended to be anchored in the bore of an element and to receive rotatably by snap-in closure a mating element provided with an undercut head. The locking apparatus according to the invention includes a substantially cylindrical body having first and second ends. Outwardly directed gripping means are arranged in the peripheral surface of the body at its first end. The body has a coaxially arranged cavity which narrows toward an opening in the first end. The cavity extends to the second end of the body and the body is provided there with an inwardly directed flange. The body is expansible or flexible at the first end.

Abstract: An expansible plug made of a plastic material located in a drilled hole in masonry for receiving a fastening screw and comprising expansible legs having at the expansible end thereof outer notches of a reduced depth.

Abstract: An arrangement for mounting a device on a wall in which the device includes a wall mounting pad having at least two fastener receiving openings. A plastic base plate is provided with at least two integral screw anchors that extend transverse to the rear side of the base plate at locations corresponding to the spaced locations of the fastener receiving openings in the mounting pad. Screw fasteners are adapted to be screwed into the wall anchor to expand the wall anchors into firm engagement with the opening in the wall and to provide mounting fasteners for attaching the mounting pad to the base plate.

Abstract: A two-piece, malleable iron, expansion anchor for installation in a relatively small (about 1") diameter bore hole with a conventional size (5/8") bolt. The four-prong expansion shell, camming plug, and individual shell leaves each have unique features contributing to the effectiveness of the anchor when used either with or without a resin grouting mixture. The slots or spaces between adjacent shell leaves include upper and lower portions, each of constant width, the lower portion being wider than the upper portion, whereby the leaves are narrower in the area where they are bent outwardly from the closed ring at the base than in the area where they are compressionally engaged between the plug and the hole wall. Upper portions of the inner leaf surfaces taper toward the shell axis and the side edges of such surfaces taper toward one another from the upper, free ends of the leaves toward the lower ends. An axial rib extends outwardly from the surface of the camming plug over its entire length.

Abstract: An expansion dowel assembly includes an axially extending anchor bolt and an expansion sleeve laterally enclosing the bolt. At its leading end, the anchor bolt has an expansion cone displaceable opposite to the insertion direction of the dowel assembly relative to a conically shaped expansion region at the leading end of the sleeve. Initially, the cone angle of the expansion cone is larger than the cone angle of the expansion section of the sleeve. A circumferentially extending annular bead is located on the outer circumferential periphery of the expansion region. The expansion region is slotted in the axial direction and its wall thickness decreases in the circumferential direction toward the slots. At the outset of the sleeve expansion, it is greatly widened and the annular bead is pressed into the surface of the borehole in which the dowel assembly is inserted.

Abstract: An improved expansion assembly for a mine roof bolt has a tapered plug, two expansion leaves that bear against the tapered plug, a bail that connects the expansion leaves and extends over the end of the mine roof bolt, and a breakable holding ring to keep the expansion assembly assembled until after it is placed into the bore hole. The tapered plug has a threaded bore therethrough for threading onto the mine roof bolt. The tapered plug also has tapered surfaces that have an angle of taper of 80.degree. to the axis of the mine roof bolt. The expansion leaves each have nine serrations formed on the surface such that the serrations are formed by the intersection of a planar surface perpendicular to the axis of the mine roof bolt and a frusto-conical surface. The frusto-conical surface is at an angle of 69.degree. to the planar surface. The serrations are equally spaced from each other and have a peak to peak distance of 0.25". The expansion leaves each have a maximum length of 3".

Abstract: A re-usable plastic drive rivet is of the type comprising an axially extending shank in association with an axially extending drive pin which is axially drivable into a bore extending axially through the shank. In order to permit release of the entire drive rivet by means of an unscrewing operation, without damaging the workpieces to which the drive rivet is secured, the outer surface of the shank has a thread formation thereon with the outer surface of the drive pin having a non-cylindrical outline complementary to a similar non-cylindrical peripheral outline of the interior wall of the bore. The non-cylindrical outlines can be substantially cylindrical apart from inter-engagable axial ribs and grooves. The shank can be integrally formed with the drive pin through means of frangible connections, but alternatively the shank can be preassembled with the drive pin by inserting the drive pin into the bore through the shank.

Abstract: A securing device includes an outer cylinder having a hollow cylindrical portion with a flange provided at one end, and an insertion member having a rod-like portion to be inserted into the outer cylinder. The hollow cylindrical portion of the outer cylinder has a plurality of slits open at the other end, an inwardly projecting portion provided at the other end, and a plurality of engagement ribs projecting outwardly from the outer periphery of the cylindrical portion. A rod-like portion of the insertion member has a head portion provided at one end, an intermediate large diameter portion having an outer diameter which is greater than the inner diameter of the inwardly projecting portion of the outer cylinder, and a small diameter portion having an outer diameter smaller than the inner diameter of the inwardly projecting portion of the outer cylinder. The small diameter portion is provided upon the side of the large diameter portion which is located nearer the head portion of the insertion member.

Abstract: An expansion shell is formed from a single piece of sheet metal consisting of two spade-shaped leaves connected by a narrow portion which becomes the bail. The leaves are corrugated along their transverse axes so as to form a series of undulations of increasing amplitude and the leaves are formed into semi-cylinders. The corrugated semi-cylindrical leaves are centrally slotted along their longitudinal axes so as to form four leaf segments. The corrugated leaf segments are then compressed along their longitudinal axes so as to cause the undulations to form a tapered pleated metal fold, wherein the crests of the undulations become semi-cylindrical ridges capable of gripping the rock formation.

Abstract: A u-shaped climbing rung to be anchored in a bore hole in a wall, the climbing rung having two parallel legs each leg having two ends, one end of each leg being connected to a transverse central element or tread spaced a predetermined distance below the parallel legs and having the other end for anchoring in a wall, the legs and tread being completely encapsulated in a synthetic protective coat having an outer configuration adapted to present each end of the legs remote the tread for anchoring the climbing rung in the wall. Behind said anchoring means each encapsulated end receives a soft elastic and tightly fitting and slidable sealing collar. At least one surface of either the encapsulated end behind the anchoring means or the inside surface of the sealing collar presents alternating raised rings and annular grooves to frictionally engage and seal the interface between the encapsulated end and the inside surface of the sealing collar.

Abstract: A reusable anchor is disclosed for securing a supporting base plate in place along the surface of a substrate to be drilled. The anchor comprises an anchor body having a first body portion engageable to the base plate and a second body portion extendable into the substrate to be drilled. The second body portion comprises first and second cylindrical sections. The first cylindrical section is disposed in axial alignment with the first body portion and the second cylindrical section is formed to vary between a first postion in axial alignment with respect to the first body portion and a second position eccentric with respect to said first body portion. The first and second cylindrical sections are adapted to cooperatiely engage the substrate when the second cylindrical section is disposed in the second position to maintain the anchor body in place with respect to the substrate.