In a screw-coupling structure between an internally-threaded body and an externally-threaded body, for connecting reinforcing bars: the internally-threaded body includes, on the inner diameter thereof, a parallel-tapered-integrated internal thread section formed by integrating a parallel internal thread section formed as a parallel screw thread, with a tapered internal thread section formed on one end of the parallel internal thread section so that the minor diameter thereof gradually narrows; and the externally-threaded body comprises, on the outer diameter thereof, a parallel-tapered-integrated external thread section formed by integrating a parallel external thread section formed as a parallel screw thread, with a tapered external thread section formed on one end of the parallel external thread section so that the major diameter thereof gradually narrows.

A locking nut system includes a threaded member with a first threaded area having a first thread direction and a second threaded area having a second thread direction opposite the first thread direction in which a plurality of crests extend across the first and second threaded areas with a constant pitch between the crests such that minimal material is removed, structural integrity is maintained, and a first nut secures the threaded member to a workpiece and a second opposing nut renders the first nut stationary.

The present invention relates to a unit (10) for a locking device, including: a nut (12) comprising first (18) and second (20) coaxial taps in opposite directions; and a ring (13); said ring including a third tap (38); the first (18) and third (38) taps being capable of engaging with a single first thread (22); said ring including a second thread (40) capable of engaging with the second tap (20) of the nut. A portion (33) of the ring, projecting relative to the second thread (40), includes a through-hole (60); and a surface (16) of the nut includes a visual marking, configured to be opposite the hole (60) when the nut and the ring are in an installation position, and separated from said hole when the nut and the ring are outside said installation position.

The present invention relates to a unit (10) for a locking device, including: a nut (12) comprising first (18) and second (20) coaxial taps in opposite directions; and a ring (13); said ring including a third tap (38); the first (18) and third (38) taps being capable of engaging with a single first thread (22); said ring including a second thread (40) capable of engaging with the second tap (20) of the nut. A portion (33) of the ring, projecting relative to the second thread (40), includes a through-hole (60); and a surface (16) of the nut includes a visual marking, configured to be opposite the hole (60) when the nut and the ring are in an installation position, and separated from said hole when the nut and the ring are outside said installation position.

A wheel nut assembly for fixing a wheel to a vehicle hub which includes a wheel nut with an internal thread and an axial body extension on said nut including a first section with an internal set of axial grooves or ribs and a second section containing a second internal screw thread. There is also a wheel stud having an external thread to co-operate with the internal thread of said wheel nut and having an end portion adapted to project beyond the wheel nut which end portion includes axial grooves or ribs on its external surface. An axial retaining cap consists of an upper externally screw threaded first portion which is adapted to engage the second internal screw thread of said body extension of said nut and attached to said first portion a second cap portion having internal grooves or ribs complementary to the external ribs or grooves on said wheel stud adapted to fit over said wheel stud and having external ribs or grooves adapted to engage the internal set of axial grooves or ribs on the first section of said body extension of said wheel nut. The first portion of said retaining cap is able to be rotated so that it moves axially down the internal screw thread of the second section of said body extension of said wheel nut so that the second portion of said cap is pushed down the end of said wheel stud and is held between the external ribs and grooves of the end of said wheel stud and the internal ribs and grooves of the first section of said body extension of said wheel nut.

A wheel nut assembly for fixing a wheel to a vehicle hub which includes a wheel nut with an internal thread and an axial body extension on said nut including a first section with an internal set of axial grooves or ribs and a second section containing a second internal screw thread. There is also a wheel stud having an external thread to co-operate with the internal thread of said wheel nut and having an end portion adapted to project beyond the wheel nut which end portion includes axial grooves or ribs on its external surface. An axial retaining cap consists of an upper externally screw threaded first portion which is adapted to engage the second internal screw thread of said body extension of said nut and attached to said first portion a second cap portion having internal grooves or ribs complementary to the external ribs or grooves on said wheel stud adapted to fit over said wheel stud and having external ribs or grooves adapted to engage the internal set of axial grooves or ribs on the first section of said body extension of said wheel nut. The first portion of said retaining cap is able to be rotated so that it moves axially down the internal screw thread of the second section of said body extension of said wheel nut so that the second portion of said cap is pushed down the end of said wheel stud and is held between the external ribs and grooves of the end of said wheel stud and the internal ribs and grooves of the first section of said body extension of said wheel nut.

An arrangement is for securing a nut on a threaded bolt comprising a bolt shaft projecting from a bolt head and being provided, in an opposite end portion, with a first threaded portion arranged to engage with an internal threaded portion of the nut. The nut and the bolt head are arranged to abut against adjacent elements. A nut-locking element is provided with a threaded portion arranged to engage with a second threaded portion of the threaded bolt. The second threaded portion is arranged externally on a stepped end portion of the threaded bolt and is concentric with and having a smaller pitch than the first threaded portion. The nut-locking element is provided with a friction portion arranged to rest supportingly against a corresponding friction portion on the nut.

A locking nut system includes a threaded member with a first threaded area having a first thread direction and a second threaded area having a second thread direction opposite the first thread direction in which a plurality of crests extend across the first and second threaded areas with a constant pitch between the crests such that minimal material is removed, structural integrity is maintained, and a first nut secures the threaded member to a workpiece and a second opposing nut renders the first nut stationary.

A lock nut includes: a first nut having a tapered cavity; and a second nut including a base portion and a tapered lug boss arranged the base portion. The tapered lug boss can be coupled inside the tapered cavity. The first and second nuts are used in pair by self-locking. A straight slot is formed in the lug boss. Under the locking action of the first nut, the straight slot is deformed to further lock a bolt, or is discontinuously engaged with teeth of the bolt to increase an effective stress surface and locking performance of the second nut for locking the bolt. A convex reinforcing rib extends on a first surface of the first nut. An annular groove is formed in a second surface of the second nut. The convex reinforcing rib is coupled with the annular groove to enhance the strength and reliability of locking.

A lock nut includes: a first nut having a tapered cavity; and a second nut including a base portion and a tapered lug boss arranged the base portion. The tapered lug boss can be coupled inside the tapered cavity. The first and second nuts are used in pair by self-locking. A straight slot is formed in the lug boss. Under the locking action of the first nut, the straight slot is deformed to further lock a bolt, or is discontinuously engaged with teeth of the bolt to increase an effective stress surface and locking performance of the second nut for locking the bolt. A convex reinforcing rib extends on a first surface of the first nut. An annular groove is formed in a second surface of the second nut. The convex reinforcing rib is coupled with the annular groove to enhance the strength and reliability of locking.