Magnetic Slip Ring

Magnetic Slip Ring is an innovative slip ring that uses optical fibers as the data transmission medium and achieves energy and signal transmission between rotating and fixed components through non-contact magnetic coupling technology. Its core advantage lies in replacing the physical contact between traditional brushes and conductive rings with optical fibers, solving the pain points of traditional Slip Rings such as wear, signal attenuation, and electromagnetic interference in high-speed rotation scenarios. It is suitable for complex systems that require continuous rotation and transmission of large capacity data, signals, or power.

technology

Non contact optical fiber transmission

Magnetic Slip Rings use optical fibers as data transmission carriers, supporting lossless transmission of gigabit bandwidth (such as 1Gbps Ethernet) and high-frequency signals (above 100MHz). Its non-contact design avoids the wear and tear caused by friction in traditional electric brush Slip Rings (traditional electric brushes have a lifespan of about 30 million revolutions, while magnetic slip ring optical fibers have a lifespan of over 1 billion revolutions), while reducing the signal attenuation rate to<0.1dB/km (traditional copper cables have an attenuation rate of about 3dB)/ km@1GHz ）. In medical CT equipment, magnetic slip rings can achieve high-definition video between rotating and fixed parts of X-ray tubes（ 4K@60fps ）Synchronized with the control signal transmission, and with a high-speed rotation of 15000 revolutions per minute, the signal error rate is less than 10 ⁻¹ ².

Anti electromagnetic interference and safety

Magnetic slip rings achieve electrical insulation through fiber optic isolation, with insulation resistance greater than 10 ¹⁴ Ω and dielectric strength greater than 5kV (DC), effectively shielding external electromagnetic interference (EMI). In military radar systems, magnetic slip rings can withstand an electromagnetic field strength of 100V/m, ensuring the stability of radar signals under high-speed rotation (20000 revolutions per minute). In addition, the inherent safety of fiber optic transmission avoids the risk of electric sparks that may occur with traditional brush slip rings, making it irreplaceable in explosive environments such as oil and gas exploration and coal mine monitoring.

Low maintenance and long lifespan

Magnetic slip rings have no mechanical contact parts and do not require regular replacement of brushes or lubrication. The maintenance cycle can be extended to more than 5 years (traditional brush slip rings have a maintenance cycle of about 6 months). Its modular design supports quick replacement of fiber optic modules, with a single module replacement time of less than 30 minutes. In the wind turbine pitch system, the magnetic slip ring can operate continuously for 15 years (with a lifespan of ≥ 1 billion revolutions), while the traditional electric brush slip ring has a lifespan of only 3-5 years.

Application scenarios and industry value

Medical equipment field

In spiral CT equipment, the magnetic slip ring needs to support continuous rotation of the X-ray tube at a rate of 3-5 revolutions per second, while transmitting high-power (30kW) and high-definition video signals（ 1080P@60Hz ）. Its fiber optic transmission bandwidth can meet the transmission needs of future 8K medical images, and it can maintain stable performance even at extreme temperatures ranging from -40 ℃ to+85 ℃. According to market research, the global market size of medical imaging equipment slip rings is expected to grow from 180 million yuan in 2023 to 280 million yuan in 2030. Magnetic slip rings occupy over 40% of the high-end market share due to their high reliability and low maintenance costs.

Aerospace and Military Industry

In satellite communication antennas, the magnetic slip ring needs to withstand high radiation (total dose>100krad) and extreme temperature differences (-180 ℃ to+120 ℃) in the space environment, and its fiber transmission loss is less than 0.3dB/km in the C-band (4-8GHz). In military radar systems, magnetic slip rings support 360 ° unrestricted rotation of phased array antennas, with a transmission power density of up to 50W/cm ², while controlling signal phase errors to<0.1 °.

Industrial Automation and New Energy

In industrial robot joints, magnetic slip rings can synchronously transmit power (48V/20A) and real-time control signals (EtherCAT bus, speed 100Mbps) with a response delay of less than 1ms. In wind power pitch systems, magnetic slip rings support power transmission (690V/100A) and synchronous transmission of SCADA monitoring data, with an anti vibration capability of 10g (acceleration), meeting the IEC 61400-1 standard.

Maintenance and upkeep guide

Fiber optic cleaning and testing

Use a fiber optic cleaning pen (such as Fiber Optic Cleaning Pen) to clean the fiber optic end face, avoiding the use of organic solvents such as alcohol. Use an optical power meter to detect fiber attenuation every quarter, and the normal value should be less than 0.3dB (single-mode fiber @ 1310nm). If the attenuation is greater than 0.5dB, it is necessary to check whether the fiber optic connector is loose or contaminated.

Lubrication of rotating components

The magnetic coupling components of the magnetic slip ring need to be coated with high-temperature grease (such as Mobil SHC 634) every 2 years, with a coating amount controlled at 0.1-0.2g/bearing. In extreme working conditions (such as high temperature>100 ℃), perfluoropolyether grease (such as Krytox GPL205) should be used instead.

Sealing and waterproofing

The protection level of the magnetic slip ring should reach IP67, and the sealing ring (such as O-ring) should be regularly inspected for aging or damage. In humid environments (relative humidity>80%), it is recommended to replace desiccants (such as silica gel particles) every 6 months.

Fault diagnosis and replacement

If there is a signal interruption or abnormal power transmission, an oscilloscope should be used to detect the waveform of the fiber optic signal (the normal waveform should have no distortion or attenuation). When replacing fiber optic modules, it is necessary to ensure that the model matches (such as single-mode/multi-mode fiber, FC/SC interface), and use a fiber fusion splicer (such as Fujikura 70S) for low loss fusion splicing (fusion loss<0.05dB).