A connecting structure for a drill collar of a logging while drilling instrument and drill collar sub male and female joints are provided. The connecting structure for a drill collar of a logging while drilling instrument includes a male connecting joint and a female connecting joint matched with each other. The male connecting joint and the female connecting joint are rotatable relative to each other. Electrical passages are respectively arranged in the male and female connecting joints. One of the male and female connecting joints is provided with a multi-core coaxial electrical male connector connected with the electrical passage, and the other is correspondingly provided with a multi-core coaxial electrical female connector connected with the electrical passage. The male connecting joint is coaxially nested in the female connecting joint. The multi-core coaxial electrical male connector is inserted into and fitted to the multi-core coaxial electrical female connector.

A slip ring assembly includes a housing having a stator that rotatably supports a rotor. The rotor includes conductive disks that are electrically connected to respective conductors extending through a rotor shaft. The stator includes brushes that slidably and electrically engage the conductive disks. The one or more brushes are electrically connected to stator conductors extending at least partially through the stator. Electrical pathways are defined and extend from the stator conductors, the brushes, the conductive disks, and the respective conductors in the shaft. A smart board is connected to the stator and includes electronic components configured to monitor operation of the slip ring assembly and provide signals to an external source. The smart board is electrically connected to, and powered by, electrical power that is present and available on the stator conductors.

An overhead lift apparatus includes a mounting structure and a rotatable assembly configured to attach a lift unit to the mounting structure. The rotatable assembly is rotatable with respect to the mounting structure about an axis of rotation. The apparatus also includes a rotatable electrical interface disposed in the rotatable assembly, the rotatable electrical interface comprises a static portion and a rotatable portion attached to the rotatable assembly such that the rotatable portion rotates in conjunction with the rotatable assembly. The apparatus also includes a first electrical connector extending from the static portion to a power source connector configured to be connected to an external power source for the lift unit. A second electrical connector extends from the rotatable portion such that the rotatable electrical interface is configured to provide power from the power source to an end of the second electrical connector via the first electrical connector.

An overhead lift apparatus includes a mounting structure and a rotatable assembly configured to attach a lift unit to the mounting structure. The rotatable assembly is rotatable with respect to the mounting structure about an axis of rotation. The apparatus also includes a rotatable electrical interface disposed in the rotatable assembly, the rotatable electrical interface comprises a static portion and a rotatable portion attached to the rotatable assembly such that the rotatable portion rotates in conjunction with the rotatable assembly. The apparatus also includes a first electrical connector extending from the static portion to a power source connector configured to be connected to an external power source for the lift unit. A second electrical connector extends from the rotatable portion such that the rotatable electrical interface is configured to provide power from the power source to an end of the second electrical connector via the first electrical connector.

A rotor including a rotor shaft, a rotor body formed of a stack of laminations, a field coil wound around the rotor body, and at least one slip ring mounted on the rotor shaft and configured to exchange electric power with an external power supply. Each of the at least one slip ring is configured to be electrically connected to an end of the field coil through an electrical connector. The electrical connector is pre-bended such that to comprise an axial portion and a radial portion respectively located on both sides of a bend, the axial portion being configured to pass through an axial bore of the rotor shaft, the radial portion being configured to pass through a through bore of the rotor shaft.

A rotor including a rotor shaft, a rotor body formed of a stack of laminations, a field coil wound around the rotor body, and at least one slip ring mounted on the rotor shaft and configured to exchange electric power with an external power supply. Each of the at least one slip ring is configured to be electrically connected to an end of the field coil through an electrical connector. The electrical connector is pre-bended such that to comprise an axial portion and a radial portion respectively located on both sides of a bend, the axial portion being configured to pass through an axial bore of the rotor shaft, the radial portion being configured to pass through a through bore of the rotor shaft.

A dual spring contact assembly having an intermediate component between at least two canted coil springs with opposite canting angle directions for fitment between a first component and a second component. When there is relative displacement between the first and second components, the direction of movement of one of the components relative to one of the canted coil spring can always occur along the canting angle, reducing the friction between coils and component and increasing the life of the slip ring.

A dual spring contact assembly having an intermediate component between at least two canted coil springs with opposite canting angle directions for fitment between a first component and a second component. When there is relative displacement between the first and second components, the direction of movement of one of the components relative to one of the canted coil spring can always occur along the canting angle, reducing the friction between coils and component and increasing the life of the slip ring.

The present invention is an electrical slip ring device comprised of a stator, a rotor and an independent rotationally free brush ring. The brush ring may include a multitude of slipping fingers, chevrons or other current carrying structures that extend between the rotor and the stator. These current carrying structures have a directional bias or “lay”. The rotational freedom of the brush ring enables bi-directional movement of the rotor with reduced torque and wear at the sliding interfaces because sliding always occurs in the direction of the lay.

The present invention is an electrical slip ring device comprised of a stator, a rotor and an independent rotationally free brush ring. The brush ring may include a multitude of slipping fingers, chevrons or other current carrying structures that extend between the rotor and the stator. These current carrying structures have a directional bias or “lay”. The rotational freedom of the brush ring enables bi-directional movement of the rotor with reduced torque and wear at the sliding interfaces because sliding always occurs in the direction of the lay.