Introduction to Non-contact Slip Ring Types

Slip rings are components that enable thetransfer of various energy and signals through 360° rotation. Different types of slip rings have structural differences based on their functionalities. While the majority of slip rings utilize a friction interface, there is also a category known as non-contact slip rings. Among these non-contact slip rings,the most representative product is the fiber optic slip ring. As an international slip ring manufacturer, JINPAT has the capability to mass-producesingle-mode fiber optic slip rings with up to 10 channels and multi-mode fiberoptic slip rings with up to 15 channels. Fiber optic slip rings fall under the category of non-contact slip rings specifically designed for optical coupling.

The transmission principle of fiber optic slip rings involves directing infrared signals of specific wavelengths througha collimator on the rotor end onto various optical lenses or prism systems within the fiber optic slip ring. The signals are then reflected back to thestator end. In this process, there is no need for contact between the statorand rotor. This characteristic allows non-contact slip rings like fiber optic slip rings to have a significantly extended lifespan. The fiber optic slip rings developed by JINPAT typically have a total lifespan of over 50 million revolutions, with certain specially designed structures capable of exceeding100 million revolutions. Since fiber optic slip rings do not transmit electrical or other forms of energy, they can be classified as optical devices from a broader physics perspective.

In addition to fiber optic slip rings,liquid metal slip rings are also an important type of non-contact slip rings.Among them, mercury slip rings are a representative example of liquid metalslip rings. Unlike conductive slip rings that use friction interfaces forelectrical energy transfer, mercury slip rings employ mercury as thetransmission medium, and there is no contact between the rotor and statorduring operation. However, due to the significant pollution caused by mercury,it is expected to be completely phased out in the coming years. JINPAT, as a pioneerin the slip ring industry, has successfully developed a new type of liquidmetal slip ring in 2018, achieving a lifespan exceeding 100 million rotations by implementing innovative design of dynamic sealing structures and avoiding patent infringements.

After multiple rounds of testing and improvement, JINPAT is now introducing these non-contact liquid metal sliprings to the market. The latest product available is a single-channel liquid metal slip ring capable of carrying currents up to 250A. In the future, more models of liquid metal slip rings will be continuously introduced based on market demands. Compared to non-contact transmission of electrical and optical signals, the transmission of electromagnetic signals and electrical energy in non-contact slip rings is much more challenging. The technical principle of non-contact electromagnetic coupling slip rings involves utilizing high-frequency electromagnetic induction and radio frequency transceiver technology to achieve non-contact power and signal transmission between the relative rotating inner and outer ring structures. Due to their niche application, thesenon-contact electromagnetic coupling slip rings are currently found mainly in laboratories or at the small-scale trial production stage.