The invention at hand refers to a wheel disc brake assembly comprising a wheel rim, a coupler ring and an annular brake disc arranged in a concentric manner, wherein an outer surface of the coupler ring is connected to an inner surface of the wheel rim and an inner surface of the coupler ring is connected to an outer surface of the annular brake disc. The wheel disc brake assembly further comprises a caliper with at least two brake pads facing each other, wherein the caliper surrounds at least a part of the inner surface of the annular brake disc and the at least two brake pads are configured to press against opposite side faces of the annular brake disc.

An automobile wheel having a multilayer rim includes a wheel disc and a rim that is composed of at least two layers of metal rings by nesting, and a gap is preset between two adjacent metal rings; an outer side of one end of the wheel disc includes axial rim mounting grooves, and one end of the rim is inserted into the rim mounting grooves to fix the rim to the wheel disc.

A wheel/hub assembly includes an axle shaft, a wheel, and a hub supporting the wheel on the axle shaft. The wheel/hub assembly has a target resonant frequency of vibration. A tuned mass-spring damper is vibrationally coupled to the wheel/hub assembly, and has a counteracting resonant frequency of vibration that is predetermined with reference to the target resonant frequency of vibration.

A rear axle assembly designed to fit within a predefined rear axle envelope of a transportation vehicle. The rear axle assembly comprising first and second double wheel hubs each supporting a pair of tires, a rear axle offset with respect to a central axis of the rear axle assembly, a rear axle input for receiving a drive input, first and second portal housings which facilitate respectively connecting the rear axle with the first and the second double wheel hubs, a four-point control arm for connecting the rear axle to a chassis, first and second spring carriers each carrying smaller and larger diameter air bellows, first and second longitudinal arms which interconnected the rear axle to the chassis, and first and second shock absorbers each located generally at or adjacent to the central axis and radially between the first double wheel hub and the first spring carrier.

A vibration resistant nut is provided for attaching a working surface to a threaded stud, the stud extending through a hole defined through the working surface. The nut includes an annulus for receiving the stud. The annulus includes a cylindrical portion and a tapered terminal end portion for being received in the hole. The tapered terminal end portion extends from the cylindrical portion. The tapered terminal end portion has an outer surface that narrows diametrically from the cylindrical portion. The nut includes a head extending from the cylindrical portion of the annulus opposite the tapered terminal end portion, the head having outer engagement surfaces for engaging a tool for rotation of the nut, the head having a threaded interior for engaging threads of the stud.

A caster may include a shaft, a first elastic ring, a C-shaped ring, and a second elastic ring. The shaft has one end inserted and secured in a wheel, and a first rod is extended from the other end of the shaft, and a second rod protrudes from an end of the first rod. The diameter of the first rod is larger than that of the second rod, and an end of the second rod comprises a flexible portion. The shaft only needs to be processed to form the second rod and the flexible portion, and the first elastic ring and the second elastic ring which are identical are adapted to be formed through the same mold so as to save the manufacturing cost.

A bicycle hub structure has a hub member, a clutch set, a driving base and a sleeve. The thread angle of the outer threaded section of the driving base is greater than the thread angle of the inner threaded section of the driving central shaft, so that the driving central shaft and the external toothed coupling collar have a coupling state instantly which greatly reduces the actuation stroke of the clutch set, improves the smoothness of driving and the sensitivity of the hub member.

A vehicle may include a flutter resistant caster. The vehicle may include a frame, a drive wheel coupled to the frame, a caster housing coupled to the frame, a caster, a locking element, a first bearing, and a biasing element. The caster housing may include an opening. The caster may include a caster wheel and a caster stem extending through the opening in the caster housing. The caster stem may be configured to rotate relative to the caster housing. The locking element may be coupled to the caster stem. The first bearing may be coupled to the caster stem. The biasing element may be coupled to the caster stem. The biasing element may be configured to exert a force on the first bearing.

A wheel/hub assembly includes an axle shaft, a wheel, and a hub supporting the wheel on the axle shaft. The wheel/hub assembly has a target resonant frequency of vibration. A tuned mass-spring damper is vibrationally coupled to the wheel/hub assembly, and has a counteracting resonant frequency of vibration that is predetermined with reference to the target resonant frequency of vibration.

A tire noise reduction apparatus may include a housing mounted on an external circumferential surface of a wheel rim on which a tire is mounted, the housing having an internal space and being open at one side in a circumferential direction of the wheel rim, wherein the housing includes a neck at an opposite side which is opposite to the open one side; and a movable member inserted into the internal space of the housing through the open one side of the housing and having an internal space in fluidical communication with the internal space of the housing, the movable member being mounted to the housing to be movable in a direction in which the movable member is inserted into the internal space of the housing and in a direction in which the movable member is withdrawn out of the housing.