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.

An intraoperative monitoring module (IMM) for assessing strength of screw attachments to bone and detecting breaches includes a torque sensor on a rotatable tool receptacle and a variable-output current source. The IMM provides concurrent monitoring of rotational torque applied to a screw and stimulus current passing through the screw into bone for evoked electromyography. A motor housing configured to drive in rotation a tool receptacle on the IMM, a screw driver modified for carrying the stimulus current, and a screw attached to the screw driver are optionally included. Cooperative anti-rotation features on the motor housing and IMM support accurate torque measurements and prevent the outer housing of the IMM from rotating with the tool receptacle while a screw is being driven. The motor housing optionally provides electrical power to the IMM.

A surgical instrument includes a slip-ring contact assembly. The slip-ring contact assembly includes an insulative housing defining a plurality of slots. A plurality of slip-ring contacts is operably supported in the insulative housing. Each slip-ring contact is configured to engage one or more electrical contacts formed circumferentially around a rotatable shaft of the surgical instrument. Each slip-ring contact includes a tang extending through a corresponding slot defined in the insulative housing and configured to be operably connected to an external wire connection. The plurality of slip-ring contacts is configured to allow unlimited rotation of the rotatable shaft while maintaining continuous electrical contact between each slip-ring contact and the corresponding electrical contact of the rotatable shaft.

A surgical instrument includes a slip-ring contact assembly. The slip-ring contact assembly includes an insulative housing defining a plurality of slots. A plurality of slip-ring contacts is operably supported in the insulative housing. Each slip-ring contact is configured to engage one or more electrical contacts formed circumferentially around a rotatable shaft of the surgical instrument. Each slip-ring contact includes a tang extending through a corresponding slot defined in the insulative housing and configured to be operably connected to an external wire connection. The plurality of slip-ring contacts is configured to allow unlimited rotation of the rotatable shaft while maintaining continuous electrical contact between each slip-ring contact and the corresponding electrical contact of the rotatable shaft.

A brush wear indicating arrangement is provided. The brush wear indicating arrangement includes an insert, a first electrically conductive brush, and a wear indicator. The insert is disposed within a brush block housing and defines a first aperture. The first electrically conductive brush is movably engaged within the first aperture. The electrically conductive brush is configured to move outward from the first aperture as a wear surface of the first electrically conductive brush wears. The wear indicator is coupled to the first electrically conductive brush. The wear indicator is configured to extend beyond a first insert face of the insert as wear condition of the wear surface of the first electrically conductive brush exceeds a wear threshold.

A brush wear indicating arrangement is provided. The brush wear indicating arrangement includes an insert, a first electrically conductive brush, and a wear indicator. The insert is disposed within a brush block housing and defines a first aperture. The first electrically conductive brush is movably engaged within the first aperture. The electrically conductive brush is configured to move outward from the first aperture as a wear surface of the first electrically conductive brush wears. The wear indicator is coupled to the first electrically conductive brush. The wear indicator is configured to extend beyond a first insert face of the insert as wear condition of the wear surface of the first electrically conductive brush exceeds a wear threshold.

A slip ring system for a wind turbine for electrically connecting a first electrical device and a second electrical device, wherein the first electrical device is mounted to a rotor of the wind turbine, and the second electrical device is mounted to a nacelle of the wind turbine, is provided. The slip ring system comprises a slip ring apparatus and a rotational damping apparatus, with which an electrical connection between the first electrical device and the second electrical device can be established. The slip ring apparatus has a rotatable component with a rotatable electrode and a non-rotatable support electrode, wherein the rotatable electrode is electrically connected to the first electrical device, and the support electrode is electrically connected to the second electrical device. The non-rotatable support electrode and the rotatable electrode are arranged with respect to each other's position and configured such that an electrical connection can be established between the non-rotatable support electrode and the rotatable electrode. The rotational damping apparatus connects the turbine rotor and the slip ring apparatus. The rotational damping apparatus prevents vibrations at least partially from migrating into the rotatable component. The rotational damping apparatus comprises a slip ring portion, a shaft portion and a damping portion. The slip ring portion is mounted to the rotatable component and the shaft portion is adapted for being mechanically connected to the turbine rotor for rotating with the turbine rotor.

The disclosed invention is a slip ring assembly that provides electrical power transfer to centrifugal turbomachinery while minimizing or eliminating the presence of wires in the flow path. The device transfers electrical power through a set of wires connected to a plurality of brushes that are held rotationally stationary, but allowed to displace axially or radially through a set of springs. The brushes make contact with conductive busbar rings, transferring electricity to the busbar rings. The busbar rings rotate with the centrifugal turbomachine with a set of wires that connect the busbar rings to the blades or other aerodynamic surfaces of the centrifugal turbomachine.

The disclosed invention is a slip ring assembly that provides electrical power transfer to centrifugal turbomachinery while minimizing or eliminating the presence of wires in the flow path. The device transfers electrical power through a set of wires connected to a plurality of brushes that are held rotationally stationary, but allowed to displace axially or radially through a set of springs. The brushes make contact with conductive busbar rings, transferring electricity to the busbar rings. The busbar rings rotate with the centrifugal turbomachine with a set of wires that connect the busbar rings to the blades or other aerodynamic surfaces of the centrifugal turbomachine.