Abstract: A friction clutch wherein the leaf springs which confine the pressure plate to axial movement relative to the housing are secured to the pressure plate by fastening devices having solid or tubular connecting elements a first portion of each of which is anchored in a discrete blind bore of the pressure plate and each of which extends outwardly through and beyond an opening in the respective leaf spring. Those portions of the connecting elements which extend outwardly beyond the openings of the respective leaf springs are deformed to constitute rivet heads which overlie the leaf springs and hold them against movement away from the respective surface of the pressure plate. Such mode of fastening the leaf springs to the pressure plate allows for a reduction of the radial dimensions and weight and enhances the safety of the clutch, especially as concerns the bursting strength of the pressure plate.

Abstract: The axially movable pressure plate of a friction clutch for motor vehicles is non-rotatably secured to the housing by a set of leaf springs each of which has an end portion overlying that surface of the pressure plate which faces away from the clutch plate. The end portion of each leaf spring has an opening in register with the open end of a blind bore in the surface of the pressure plate. Such end portions of the leaf springs are permanently fastened to the pressure plate by tubular connecting elements having (a) enlarged end portions overlying those sides of the leaf springs which face away from the pressure plate and (b) main portions which extend through the respective openings and into the registering blind bores and are radially expanded into pronounced frictional engagement with the pressure plate.

Abstract: A reusable two-piece fastener for releasably securing together a plurality of panels which have aligned apertures therethrough comprises a body member and an associated externally threaded screw member. The body member, which is molded of resiliently flexible compressible plastic, comprises a head at one end radially expandable/retractable legs at the other end. A cylindrical bore extends inwardly from the head end of the body member. Screw-engaging internal female threads are integrally formed on the bore wall and are arranged in axially spaced apart sets therealong, each set including a plurality of thread sections, each of which sections extends around only a part of the circumference of the bore. These female threads are resiliently movable radially outwardly either because they are inherently compressible and flexible (one embodiment) or because they are formed on outwardly swingable bore wall portions (another embodiment).

Abstract: A device for fastening an object against a wall as a plug-in mounting is described, which is provided with an externally threaded bolt, onto one end of which a nut can be threaded and on the other end of which, which is at least partially conical and the maximum diameter of which is equal at most to the diameter of the bolt, an expander element composed of two half-shell-like parts is displaceably held. The two half-shell-like expander parts are provided, on their two longitudianl edges which in the mounted state are located opposite one another, with at least two lobes each, which for mutually securing one another axially engage one another adjacently and are held on the conical end by positive adjacent engagement in the radial direction and are disposed on the expander element in such a manner that the expander element parts are transversely symmetrical or in the developed state are point-symmetrical.

Abstract: An expansion dowel assembly includes an axially elongated expansion sleeve with an axially extending expansion region, a spreader positioned within the sleeves in the expansion region, and a bolt in threaded engagement within a tapped bore in the spreader so that the spreader can be displaced axially through the expansion region for widening it in the radial direction. The surface of the spreader in surface contact with the interior of the sleeve is spherically shaped. In the assembled state, before expansion, the spreader is held in the expansion sleeve against axial displacement. Accordingly, the parts of the assembly can be preassembled as a unit.

Abstract: An expansion dowel assembly includes an axially elongated sleeve having a leading end and a trailing end, an axially extending spreading member located within the sleeve adjacent its leading end, and a threaded bolt extending into the trailing end and toward the leading end of the sleeve. The threaded bolt is axially movable within the sleeve between a first position where the dowel assembly can be inserted into the borehole and a second position where the bolt is driven further into the sleeve into expanding contact with the spreading member for radially expanding the spreading member and the sleeve. An abutment is provided for the leading end of the dowel assembly to prevent displacement of the spreading member out of the sleeve when the bolt is driven from the first position toward the second position.

Abstract: An expansion dowel assembly includes an anchor bolt and an expansion element made up of at least two expansion element parts offset from one another in the axial and circumferential direction when mounted on the anchor bolt. A web interconnects the adjacent expansion element parts. Recesses are formed in the circumferential surface of the anchor bolt for receiving the expansion element parts. Another recess connects the recesses for the expansion elements parts and is arranged to receive the web interconnecting these parts. The expansion element parts encircle the anchor bolt by more than half of its circumference so that holders are not needed for securing the expansion element on the anchor bolt.

Abstract: A wedge-type fastener which is economical to manufacture and can be installed using known installation tools, such as those used in Europe. The fastener comprises a main body portion having an exterior adapted to be grasped by a tool to hold the same and an insert mounted in its interior keyed to the interior of the main body portion for rotation therewith. A threaded stud having a head keyed to the interior of the insert is also mounted within the body portion having a threaded portion extending out of one end of the body portion. The body portion is closed off at one end by a snap-in cap which also aligns the threaded stud in the body portion and abuts against the insert. The threaded portion of the stud extends through the cap and terminates in a snap-on cap that keeps a threaded nut threaded on the threaded portion of the stud between the first cap and the second cap from running off the stud. The stud, at its other end, includes a pair of wire elements fixedly secured therein.

Abstract: A wedge-type low profile fastener is disclosed which is adapted to be inserted into aligned apertures in a pair of abutting surfaces. A hex head is provided on the fastener which is engageable by a tool to rotate the same. Such rotation moves a screw having a pair of spaced wires coupled thereto with a spreader between the wires. As the screw is moved, the wires move along the spreader wedging the spreader between the wires. This moves the wires outwardly against the non-accessible surfaces of the apertures thereby holding the fastener secure in the apertures until the wedging action is removed. The fastener presents a low profile so that the hex head does not stick out too far while retaining a predetermined grip range for the wires.

Abstract: A combination expansion shell and resin secured anchor assembly for installation in a mine roof opening including an elongated bolt having rebar attached to the upper end thereof and an expansion shell below the rebar. The assembly is inserted into a mine roof opening in the back end of which is positioned a resin and catalyst cartridge, the cartridge being ruptured by the rebar, allowing the resin and catalyst to gravitate downwardly between the opening wall and rebar, where they are mixed upon rotation of the bolt and rebar. The bolt is rotated a predetermined number of revolutions to obtain optimum mixing of the resin and catalyst, after which continued rotation of the bolt in the same direction causes outward movement of the expansion shell into gripping engagement with the mine roof.

Abstract: A method and apparatus for forming a hollow sleeve for a blind fastener including the steps of forming a sleeve blank to have an enlarged sleeve head and a through bore having a radially inwardly extending shoulder forming portion, deforming the material on the shoulder forming portion to move axially toward the sleeve head and radially inwardly from the reduced diameter bore portion and substantially deforming the material away from the sleeve head and back towards the contour of the reduced diameter bore portion to form a sleeve stop shoulder.

Abstract: A blind rivet is disposed to be inserted through openings in a pair of structures. The rivet includes a main stem having a pliable sleeve disposed therearound. The rivet includes a head portion on one end and an enlarged portion or bulb on the other. The rivet is held in place as the head portion is drawn outwardly causing the bulb portion to expand the sleeve so as to provide clinching of the two structures. After the expansion of the sleeve, the stem is driven back into the openings in the structure.

Abstract: A fixing plug contains a metallic expanding sleeve having a slotted end portion or section. Engaging with this slotted end portion is an expanding element which contains a body formed of an oscillation damping material and in which there are embedded a conical sleeve and in axial spacing therefrom a connection element or part. The conical sleeve coacts with the slotted end portion. The connection part serves for the attachment of an attachment screw of the like and for drawing the expanding element into the slotted end portion of the expanding sleeve. At the end portion located opposite the slotted end portion there is arranged an internal lining formed of an oscillation damping material. This internal lining or covering is constructed as an insert body member and possesses a part which protrudes past the expanding sleeve. The fixing plug affords both good attachment properties and good oscillation damping properties.

Abstract: A binder for panels comprises a main binder part and a wedge member so constructed that the forced insertion of the wedge member into the main binder part causes the split portions formed in the main binder part to spread out and the expansion of the split portions serves to fasten two panels to each other. Into the main binder part set in the perforations formed in advance in the panels, the wedge member can be inserted from either of the outer surfaces of the two panels.

Abstract: The fastener of the invention has a sleeve-like body with a laterally enlarged head at a rear end thereof, a fixed diameter rear portion forwardly adjacent to the head, and at least three forwardly opening longitudinal slots defining as many forwardly projecting legs. A plunger insertable into the body to a forward operative position holds the front ends of the legs flexingly diverged to confine the fastener in a blind hole. At its front end each leg has a radial protuberance with a flat rear surface, the rear surfaces of the protuberances being coplanar and normal to the body axis when the legs are diverged. A rearwardly facing circumferential shoulder on the plunger is engaged by detent lugs in the body, near the rear ends of the slots, to define a preliminarily assembled position of the plunger and is detentingly engaged by forwardly facing surfaces on the legs, near their front ends, in the operative position of the plunger.

Abstract: An expanding sleeve device for fastening a rail to a crosstie comprising a headed bolt threaded into a tapered nut. Positioned between the head and nut is a sleeve having radially expandable pronged portions and a deformable collar. The tapered nut causes the pronged portions and sleeve to expand and fit securely in a hole in the crosstie.

Abstract: A plastic fastener comprises a female member provided with a flange, a leg extended from the flange and an insertion hole bored longitudinally along the axis of the leg, and a male member provided with a head portion and a shaft portion extended from the head portion and adapted to be inserted into the insertion hole of the female member, whereby panels are brought into tight union. The female member and the male member are provided on the upper surface of the flange and on the lower surface of the head portion respectively with cam faces which are inclined in the circumferential direction around the common axis of the two members and matched so that these are brought into intimate contact at the time of the forced driving of the male member into the female member and, at the time of release of the tight union of the panels, caused to slide on each other by a rotation given to the male member to thereby cause the head portion to be lifted from the upper surface of the flange.

Abstract: A two-piece plastic fastener has a sleeve-like body comprising forwardly projecting flexible legs and having a concentric radially enlarged head at its rear end. Longitudinal slots in the body define the legs and space them apart laterally. A cylindrical plunger, forwardly insertable in the body to an operative position at which it holds the legs forwardly diverged, has two radially outwardly opening circumferential grooves, one near its front end, the other near its rear end. At the rear end of each slot in the body is a detent lug that has its rear end integrally connected with the body to have its front end flexible radially outwardly. These lugs detent-wise engage in the front groove to define a projecting position of the plunger and in the rear groove to define its operative position. Lugs and grooves are so configured as to offer more resistance to rearward than to forward plunger displacement.

Abstract: A blind rivet of plastic material, comprising a shank and a rivet body disposed round the shank and separated into an upper portion and a lower portion such that, when the shank is lifted up relative to the rivet body for the purpose of binding given panels, one of the upper and lower portions of the rivet body is caused to ride over the other of the aforementioned two portions and consequently the rivet body as a whole is expanded outwardly in the radial direction, enabling the panels to be pressed tightly against each other and secured fast in position.

Abstract: A system for reinforcing a rock formation, such as in mining or tunneling operations, wherein an elongated bolt is anchored in a blind drill hole in the rock formation by both a mechanical expansion anchor and a resin grouting mix. The invention is particularly directed to novel means which prevent relative rotation of the bolt and anchor in one direction and allow relative rotation in the opposite direction, whereby a conventional, two-compartment resin cartridge can be broken and its contents mixed while rotating the bolt and anchor in the first direction, and the anchor expanded to tension the bolt by reversing the direction of rotation before the resin mix hardens. The novel means comprise a collar element which is affixed to the end of the bolt above the expansion anchor and cooperatively engages a stop means on the anchor in only one direction of bolt rotation. A number of alternative means are disclosed for affixing the collar to the bolt.

Abstract: A blind fastener having a rivet sleeve, a core bolt, an expansible sleeve integral with the rivet sleeve, and a locking ring. The core bolt extends through the rivet sleeve and includes a sleeve expanding portion abutting against the sleeve with an enlarged stop ring at the end of the expanding portion. The ring encircles the core bolt and is disposed in a throughbore in the head of the rivet sleeve. The ring is split and has an internal chamfer for facilitating assembly regardless of irregularities on the core bolt. The core bolt has a stop thereon for preventing movement of the ring away from the head of the rivet sleeve toward a threaded portion of the core bolt.

Abstract: A mine roof bolt and expansion anchor are provided with means preventing relative rotation of the two in a direction tending to withdraw the bolt from the tapered nut of the anchor while allowing relative rotation in the opposite direction, whereby the bolt may be rotationally advanced into the nut as the anchor remains rotationally stationary to effect expansion of the anchor shell within a drill hole. A conventional, two-compartment resin cartridge is inserted into the drill hole ahead of the end of the bolt carrying the anchor. The cartridge is ruptured and the contents thereof mixed by advance of the bolt and anchor while rotating in the direction preventing relative rotation. Immediately thereafter the bolt is rotated in the opposite direction, thereby expanding the anchor and firmly securing it in the hole. The bolt may then be immediately loaded without regard to the setting time of the resin. Three embodiments are disclosed of the means providing the aforementioned relative rotational action.