A bolted attachment having opposite threaded sections between which a shank is provided having at least two shank sections with different diameter located at a length from the threaded section of at least three times the difference between a diameter of a threaded section and a minimum diameter of the shank. At least one conical transition is formed between two adjacent shank sections where the ratio of its length to a difference between a diameter at one end of the transition and a diameter at the opposite end of the transition is of at least 0.85.

According to one aspect, an apparatus includes a first member that has a first aperture and a second member adjacent to the first member and having a second aperture extending between opposed first and second faces of the second member and aligned with the first aperture to define a combined aperture that has a longitudinal extent. The second aperture is defined by a surface that has a portion having an extent transverse to the longitudinal extent. The apparatus further includes at least a portion of a fastener disposed in the combined aperture. The fastener has a first end proximal the first member and a second end proximal the second member and includes a first retaining member in contact with the first member, a second retaining member in interfering relationship with the portion, and a third retaining member in contact with the second face.

The present disclosure relates to non-cylindrical fastening systems and related methods, such as methods of installing a non-cylindrical fastening system. Presently disclosed non-cylindrical fastening systems may include a first fastening component and a second fastening component, where the second fastening component includes an elongate shank configured to be inserted through a hole in the first fastening component and through a hole in a structure to which the first fastening component is being secured. The holes in the first fastening component and the structure may be non-circular, and the elongate shank may be non-circular in perpendicular cross-section. Disclosed fastening systems may also include a third fastening component configured to be installed onto the elongate shank, and substantially prevent axial movement of the elongate shank with respect to the structure and/or first fastening component. Such fastening systems may lower the number of parts required in manufacturing an apparatus, such as an aircraft.

An attachment device includes a flange, an upper shaft, and a lower shaft. The flange defines an upper surface and lower surface. The upper shaft projects from the upper surface and is centered about an upper longitudinal axis. The lower shaft projects from the lower surface and is centered about a lower longitudinal axis. The upper longitudinal axis is not collinear with the lower longitudinal axis. So configured, the attachment device allows two objects to be attached to each other with a lateral offset equal to the lateral offset between the upper shaft and the lower shaft.

A bolt and a method for manufacturing the bolt are provided. The bolt includes a screw cap and a bolt bar, the bolt bar includes a positioning bar, a flexible bar and a threaded portion, the positioning bar is connected to one end of the screw cap, and the flexible bar is connected to the positioning bar and the threaded portion respectively. Wherein, an anti-shearing stand is formed on the flexible bar. The threaded portion includes standard threads and transition threads, the transition threads are formed between the flexible bar and the standard threads, and a thread height of the transition threads is smaller than a thread height of the standard threads, wherein the thread height of the standard threads keeps constant. The force distribution of the threads can be optimized, and the threads can effectively cooperate with the threads of the nut.

A fastener for improved electrical contact with a composite structure and improved distribution of electric current to the composite structure. The fastener includes an elongated shaft having a first end with a head portion, a second end with a threaded portion, and a shaft body therebetween. At least one feed channel extends from an opening at the threaded portion, through the shaft body, and terminates proximal to the head portion. The shaft body radially expands upon pressure injection of a resin filler into the feed channel, when the fastener is installed in a corresponding fastener hole formed in the composite structure. Upon radially expanding, the outer surface of the shaft body makes contact with an inner hole surface of the corresponding fastener hole, resulting in the fastener providing electrical contact with the composite structure and providing distribution of electric current.

A flat-formed bolt is divided into an operating portion and a screwing portion, wherein the operating portion and the screwing portion are plat-formed and co-axially correspond to each other. The screwing portion has two opposite sides each formed with a series of teeth, wherein the two series of teeth are staggered relative to each other and each tooth vertically corresponds to an axis of the operating portion and the screwing portion such that the screwing portion can be screwed into a threaded hole previously defined in a work piece.

Modular packaging includes a solid state relay and a function module, wherein the function module comprises a housing containing a printed circuit board and an elevating screw. The elevating screw comprises a first end with an external threading and a second end with an external threading, where the elevating screw may be selectively altered between a first position and a second position within the housing. Related embodiments are disclosed.

The present invention provides a fastener that serves as a replacement for joining a pair of metal sheets or similar materials. The fastener can be used to replace an original fastener that has worm a large hole into the sheets of material. The fastener provides a widened shaft to accommodate the widened hole while retaining a small head size comparable to that of the original fastener. In this way, the fastener of the present invention can be used in the widened hole while retaining the appearance of the original fastener.

A fastener includes an elongated shaft having a first end, a second end, and a shaft body, a head portion, and a threaded portion. At least one inner feed channel extends through the head portion and the shaft body and terminates proximal to the threaded portion. The fastener has a plurality of flutes formed along and circumferentially spaced around an outer surface of the shaft body and an outer surface of the head portion. Each flute has a first end and extends from a first location proximal to the threaded portion, along the outer surface of the shaft body, and radially outward along the outer surface of the head portion. The fastener further has one or more lateral feed channels formed laterally through the shaft body and connecting the inner feed channel to at least two opposing flutes on the outer surface of the shaft body.