Abstract: A novel quick release fastener system for efficient and reliable attachment, disengagement and reattachment of one or more work pieces secured by the fastener system. The fastener system includes a bolt and a nut. The bolt includes a shank with a head on one end with a leading end on the shank opposite the head. The nut has a wall which generally defines a bore having opposed edges which define a slot at least partially extending through the wall. Displacement structures are provided on the nut which provide a mechanical advantage in translating rotary and axial forces into circumferential and radial forces. Threads are provided on at least the nut for promoting axial displacement for engaging and disengaging the displacement structures. Threaded engagement and disengagement of the displacement structures deform or release the wall of the nut resulting in displacement of the opposed edges of the wall. In one embodiment the nut includes a constricting gripper which is threadedly engaged with a driving body.

Abstract: A hydraulic bolt tensioner having a first chamber and a second chamber, a first hollow piston movable in the first chamber and partially extending into the second chamber, a second piston displaceable inside the first piston and movable in the second chamber, the second piston having connecting means for connecting with an end of a bolt, and a hydraulic fluid supply into the first chamber so that when hydraulic fluid pressure is applied to the first chamber, the first piston moves so that the first piston displaces the hydraulic fluid in the second chamber and moves the second piston to pull the end of the bolt.

Abstract: A retainer has inner and outer subsections that are hingedly connected. An outer portion is hingedly connected to the outer subsections. The outer subsection rotates on its hinge relative to the outer portion, and axially back towards the inner surface of the wall to contact the wall. The inner subsection extends to a connection with the inner head portion. The inner and outer subsections are in abutting contact adjacent to the hinge. The abutting contact creates a holding force at the point of contact between the hinge and the inner wall. This results in a truss-like configuration that securely retains the retainer in the wall.

Abstract: A fastener assembly for attaching a cover to a panel includes a stud assembly mounted on the cover and having a stud extending through an opening formed in the cover. The stud has a shank portion which extends through the opening in the cover, a head portion provided on an upper end of the shank portion, and a cross pin provided on a lower end of the shank portion. A grommet is secured to the cover within the opening of the cover for attaching the stud to the cover. The fastener assembly further includes a receptacle assembly including a receptacle barrel having a cylindrical wall with an interior surface having female threads formed thereon. The receptacle assembly further includes an insert having a cylindrical body with an exterior surface having male threads formed thereon. A helix is disposed between the receptacle barrel and the insert, the helix being fabricated from wire-like material and having alternating large and small diameter loops extending along the length of the helix.

Abstract: A fastener for holding panels together includes a grommet for engaging a first panel, a stud received in the grommet, and a receptacle for securement to a second panel, wherein the receptacle includes a body having an internally threaded bore, an externally threaded barrel member in engagement with the threads of the bore, curved slots in the barrel member for receiving a cross pin of the stud, and a mechanical arrangement for selectively locking the barrel member from movement relative to the body. The grommet can include diametrically opposed slots having open ends extending through an end of the grommet for receiving the cross pin of the stud.

Abstract: A screw assembly is made up of a screw and a screw fixing member. The screw fixing member is inserted into a starting hole formed in a concrete wall and then the screw is driven into the fixing member in a continuous manner. The screw fixing member has a body having a cylindrical section formed with an eccentric bore having an opening at one end thereof. The screw has its tip inserted in the opening of the bore. The screw has a threaded shank and a cylindrical portion provided at one end of the shank. The screw and the screw fixing member are coupled together by inserting the cylindrical portion of the screw into the opening of the bore.

Abstract: A fastening element for fitting into a drilled hole and a method of fixing a fastening element in a drilled hole are proposed. In the method, an expandable sleeve is fixed in the drilled hole upon drawing of an axially movable anchor, in the direction out of the drilled hole, it being possible for all the elements of the fastening element to consist of plastic.

Abstract: A fail-safe anchor bolt assembly installable in a pre-drilled hole in masonry to fasten a fixture or other object thereto, the assembly remaining securely anchored even should the hole later be enlarged as a result of a crack developed in the masonry. The assembly includes a bolt having a head engageable by a torque tool to turn the bolt and a shank extending from the head loosely encircled by an expansible shell whose normal outer diameter is close to that of the drilled hole. Threadably received on the end of the shank adjacent the shell is a wedge nut having a generally conical frustrum shape defining a leading end followed by a leading portion which merges with a compressible trailing portion terminating in a trailing end, the leading portion having a maximum diameter close to the diameter of the drilled hole and the compressible trailing portion having a normal maximum diameter greater than the diameter of the drilled hole.

Abstract: A fastener device is provided for connecting a first component having a first aperture therein to a second component having a second aperture therein. The fastener device includes an axially extending first shaft portion for connection within the first aperture of the first component and an axially extending second shaft portion for connection within the second aperture of the second component. A connector portion extends between and interconnects the first and second shaft portions to each other. The shaft portions are each made of a first material and the connector portion is made of a different second material. The second material forming the connector portion is sufficiently flexible to permit axial and transverse movement of the first and second shaft portions relative each to allow for coaxial misalignment of the first and second apertures and to provide noise and vibration isolation between the first and second components in the assembled condition.

Abstract: A self-coining fastener which may be used to join at least two sheets of metal together without leaving a coining mark on one side thereof. The present self-coining fastener therefore produces an entirely flush surface on one side of the joined layers. The fastener comprises a top surface and a bottom surface, the top surface having a larger diameter than the bottom surface. A groove is formed around a perimeter of the fastener in order to transition between the two diameter surfaces. Because the top surface of the fastener has a larger diameter, no coining ring is required in the upper die which installs the fastener. The larger diameter head acts as a self-coining manner to push the metal in the joined layers into the central groove. The result is an installed fastener in which the larger diameter top surface is entirely flush with the top surface of the joined metals, without the presence of a coining mark.

Abstract: An anchor plate (1A) has threaded sleeves (2) for mounting equipment to a sheet metal structure (5). The plate and metal structure (5) are configured to conform to one another on assembly for structure reinforcement. An elastic tongue (10, 16) integral with the plate (1A) carries a rivet (9) which contacts the structure (5) during assembly and the two in predetermined orientation during welding of the rivet (9) to the structure.

Abstract: A screw includes a head and a shank which extends from one side of the head, a substantially cubic recess defined by four sides in the other side of the head, each of the four sides having a short slot perpendicularly outwardly extending therefrom and each of the four short slots communicating with the cubic recess.

Abstract: A thread forming screw for concrete, masonry, rock, or similar material. The size ratios of various portions of the screw are defined to reduce thread engagement which, in turn, reduces screw-in torque. A burr in the screw's thread includes bow-shaped cutting teeth to facilitate screw-in.

Abstract: The present invention relates to a male and female screw set wherein the male screw comprises at least a projecting part pressing against the flank plane of the female screw when the male and female screws are engaged. A dimensional difference is formed between the pitches of the female and male screw threads. When the female and male screws are engaged, the advancing side flank plane of the female screw thread is contacted by the advancing side flank plane of the male screw thread, while the other receding side flank plane of the female screw thread is contacted by other receding side flank plane of the male screw thread, and these respective flank planes are pressed together with tightening.

Abstract: A bolt and nut formed from a plastic material are provided with the bolt having proximate and distal ends and the nut having an interior surface defining a bore. Raised projection members are formed integrally extending from the nut interior surface into the bore and together define a diameter slightly smaller than the shank diameter. In this manner, an interference fit is provided between the shank and projection members. With the bolt shank inserted through aligned holes in parts to be fastened, the nut can be mounted on the distal end of the bolt shank, as by a force fit, and slid thereon by exerting an axial force on the nut until the parts are clamped between the bolt head and nut.

Abstract: A detachable panel or grill for covering an opening in panelling of a wall or ceiling or in an appliance. The panel can be installed quickly and rigidly without the need for any special framing. The panel or grill can be installed or removed by the rotation of a single screw which passes through a threaded opening in an elongate fastening arm. The arm extends generally parallel to an inner surface of the panel during use thereof. The arm is pivotable relative to the panel between a first position usable for insertion of the arm into the opening and a second position used for clamping the panel to edge structure defining the opening. A slideway is connected to an inner surface of the panel and limits the extent of pivotal movement of the arm. The screw extends through a hole in the panel and connects the arm to the panel. A spring biases the arm so that it pivots towards the second position.

Abstract: An improved fastener comprising a head portion, a flange portion, a shank portion which extends through two aligned apertures formed in adjacent panels and a collar swaged on the shank portion. The shank portion includes a gripping portion having a plurality of gripping surfaces formed between a plurality of cone shaped grooves, the configuration of the gripping portion being spiral shaped. The collar is installed by first positioning it over the fastener shank portion, an installation tool then swaging the collar thereto, the collar being tightly held by the multiple gripping surfaces to prevent movement in the direction of the longitudinal axis of the fastener. A mating spiral shaped configuration is formed along the interior surface of the collar during the swaging process.

Abstract: A pre-load indicating washer for properly tensioning a joint held together by an externally threaded member and an internally threaded member. The pre-load indicating washer has a plurality of protuberances, struck and partially sheared from the annular body of the washer, which are pushed under load back into a corresponding number of indentations in the annular body which are formed when the protuberances are formed. The protuberances of the pre-load indicating washer are curved in outline with no portion of the protuberances extending radially outward beyond the outer periphery of the bearing surface of an externally threaded member when the pre-load indicating washer is positioned adjacent the externally threaded member, or radially outward beyond the outer periphery of the bearing surface of an internally threaded member when the pre-load indicating washer is positioned adjacent the internally threaded member.

Abstract: The shank portion of a screw, which is free of a drill bit portion and which is adapted for use with a fibrous board, has a surface that is formed with a screw thread throughout the length of the shank portion, and a lower section that is formed with a flute at the surface thereof. The flute extends from a tip of the shank portion and has a longitudinal length which is inclined with respect to a longitudinal axis of the shank portion.

Abstract: A construction anchor for mounting an object on a structure of masonry, concrete, metal or the like includes a metal anchoring portion and a plastic cap. The anchor is adapted to be inserted, metal end first, into a pre-drilled adhesive-filled hole. The cap has a flange that is larger than the hole diameter, so that the anchor may be inserted and seated in the hole at a consistent depth. When the adhesive has set, a screw or bolt is inserted through the plastic cap to engage the threads in an internal bore in the anchoring portion. The plastic cap serves not only to determine the depth of the anchor in the hole, but also to prevent adhesive and other material from entering the threaded interior of the anchor prior to use.