Disclosed is a fastener assembly comprising: a bolt member, comprising a bolt head and a shank, at least a part of which is screw threaded; a nut member for threaded engagement with the shank; a first drive element allocated to the bolt member and a second drive element allocated to the nut member, each drive element comprising a body and adapted for engagement by a corresponding tool. The body of the first drive element is joined to the bolt member by a first interposed interlayer structure. The body of the second drive element is joined to the nut member by a second interposed interlayer structure. The first interlayer structure is adapted to fracture in response to relative rotational and/or tensile force applied to the first drive element. The second interlayer structure is adapted to fracture in response to relative rotational and/or tensile force applied to the second drive element.

Disclosed is a fastener assembly comprising: a bolt member, comprising a bolt head and a shank, at least a part of which is screw threaded; a nut member for threaded engagement with the shank; a first drive element allocated to the bolt member and a second drive element allocated to the nut member, each drive element comprising a body and adapted for engagement by a corresponding tool. The body of the first drive element is joined to the bolt member by a first interposed interlayer structure. The body of the second drive element is joined to the nut member by a second interposed interlayer structure. The first interlayer structure is adapted to fracture in response to relative rotational and/or tensile force applied to the first drive element. The second interlayer structure is adapted to fracture in response to relative rotational and/or tensile force applied to the second drive element.

An aluminum alloy according to the present invention includes 1.2% by mass to 4.0% by mass of copper, 4.0% by mass to 14.0% by mass of zinc, 0.5% by mass to 4.0% by mass of magnesium, 0.01% or less of silicon, and 0.01% or less of iron, with the balance containing aluminum and inevitable impurities, and has an average equivalent circle crystal grain size of 500 nm or less.

A fastener system incorporated in a structural member, the system including a dual threaded member and an anti-rotational member. The dual threaded member is inserted through a hole in the structural member. The dual threaded member has an engaging feature. The anti-rotational member is coupled to the dual threaded member, and the anti-rotational member is coupled with the engaging feature of the dual threaded member and with the structural member to thereby limit rotation of the dual threaded member relative to the structural member.

A fastener system incorporated in a structural member, the system including a dual threaded member and an anti-rotational member. The dual threaded member is inserted through a hole in the structural member. The dual threaded member has an engaging feature. The anti-rotational member is coupled to the dual threaded member, and the anti-rotational member is coupled with the engaging feature of the dual threaded member and with the structural member to thereby limit rotation of the dual threaded member relative to the structural member.

Disclosed is a connection device for piezoceramics of an ultrasonic transducer, comprising a nut (1), an ultrasonic transducer (5) having a screw structure and to be used with the nut (1), and a plurality of piezoceramics (3) and a plurality of metal sheets (4) fitted on an outer circumference of the screw of the ultrasonic transducer (5) and arranged at intervals. The connection device for the piezoceramics of the ultrasonic transducer further comprises a washer (2) located between the nut (1) and the piezoceramics (3), and the washer (2) is provided with a through hole through which the screw passes. The connection device has high connecting precision, strong working stability, and high working reliability.

Disclosed is a connection device for piezoceramics of an ultrasonic transducer, comprising a nut (1), an ultrasonic transducer (5) having a screw structure and to be used with the nut (1), and a plurality of piezoceramics (3) and a plurality of metal sheets (4) fitted on an outer circumference of the screw of the ultrasonic transducer (5) and arranged at intervals. The connection device for the piezoceramics of the ultrasonic transducer further comprises a washer (2) located between the nut (1) and the piezoceramics (3), and the washer (2) is provided with a through hole through which the screw passes. The connection device has high connecting precision, strong working stability, and high working reliability.

A nut-and-bolt fastener is provided. The nut and bolt are configured with a plurality of interlocking teeth that provide unidirectional travel of the nut with respect to the bolt. In particular, the configuration of the teeth arrest separation of the nut from the bolt while permitting the nut to move toward the head of the bolt into a fastened engagement. The teeth are non-helical and arranged concentrically around the longitudinal axis in evenly-spaced steps or segments along the longitudinal axis and around the shaft of the bolt and bore of the nut. Integral winged washers are provided on the bolt head as well as on the nut. Variations with different rake angles of the teeth as well as an expandable nut are also provided.

A screw nut includes a through hole defined by the screw nut, an internal thread that projects into the through hole, and a face that surrounds the through hole. At least three barcode patterns are disposed on the face where the at least three barcode patterns have an identical content.

A fastening structure with two different threads includes: a rod body provided with a first thread and a second thread arranged at an outward protrusion of the first thread, wherein a pitch and a thread width of the first thread are larger than those of the second thread; and an outer member engaged on an outer side of the rod body and provided with a third thread and a fourth thread arranged at an outward protrusion of the third thread, wherein a pitch and a thread width of the third thread are larger than those of the fourth thread, and correspond to those of the first thread, and the pitch and the thread width of the fourth thread correspond to those of the second thread. When the rod body and the outer member are engaged to rotate in an unhindered manner, the first thread is engaged with the third thread, and the rod body and the outer member can be rapidly moved relative to each other. When the rod body and the outer member rotate relative to each other in a hindered manner, the first thread is disengaged from the third thread, the second thread is engaged with the fourth thread, the second thread and the fourth thread are locked with each other, and the rod body and the outer member are fixed with each other.