Design, Fabrication, and Application of High-Current Rotary Slip Rings

An electrical rotary slip ring is an electrical connector capable of transmitting signals and power while in a rotating state; during rotation, the cables used for transmitting these signals and power do not suffer from twisting damage. The primary components of an electrical rotary slip ring are the slip rings themselves and the brushes, which utilize relative rotational sliding contact between the two to facilitate the transmission of signals and power. The structural design of an electrical rotary slip ring varies significantly depending on its intended application and the magnitude of the current it is required to transmit. One existing type of electrical rotary slip ring designed for transmitting high currents comprises a hollow slip ring shaft containing internal cable connectors. Support frames are fitted over both ends of the slip ring shaft, with bearings assembled between the shaft and the frames to provide support. The section of the slip ring shaft situated between the two bearing supports is fitted with alternating layers of insulators and electrical slip rings, ensuring an insulated fit between the slip rings and the shaft. Corresponding brushes are positioned around the outer circumference of each electrical slip ring; these brushes are of a blade-like configuration, insulated and fixed to a brush mounting plate, with their working ends elastically pressed against the surfaces of the electrical slip rings.

Since this connector is designed to transmit high currents, both the electrical slip rings and the brushes are required to possess a specific current-carrying capacity; consequently, a certain contact width between the two is essential. In this particular connector design, the contact surfaces of each slip ring and brush constitute a single, continuous, and relatively broad contact area. To ensure full contact across this entire width, not only is a high degree of geometric precision required during the machining of both components, but the positional accuracy of the brushes during assembly must also meet stringent standards. This places significant demands on both machining and assembly processes, inevitably impacting manufacturing costs and efficiency. Furthermore, while the brushes must be pressed against the slip ring surfaces with considerable pressure, it remains impossible—even under such conditions—to guarantee reliable, full-width contact between the brushes and the slip rings. Inevitably, instances of localized poor contact or complete lack of contact will occur, leading to the generation of excessive heat during operation, which in turn compromises the connector's transmission capabilities and overall performance. Additionally, this structural design—characterized by a continuous, full-surface contact fit—results in uneven wear of the brushes, thereby shortening their operational lifespan. Yading Electric offers a high-current electrical slip ring designed to address the issue of excessive heat generation between the brushes and the slip ring during operation—a common problem in existing high-current slip ring designs. To achieve this objective, the following technical solution is employed: the assembly comprises a slip ring shaft upon which insulators and electrical slip rings are alternately mounted. Each electrical slip ring is electrically insulated from the slip ring shaft. Corresponding brush assemblies are positioned along the outer circumference of each electrical slip ring. Each brush assembly consists of a busbar and a brush group; the brush group is composed of individual brush units arranged axially along the slip ring relative to the busbar. Each individual brush unit is electrically connected to the busbar, and the working end of each brush unit is resiliently pressed against the surface of the corresponding electrical slip ring—specifically, the slip ring associated with that particular brush assembly—thereby establishing a rotating sliding contact interface.