Electrical slip rings play a crucial role in automation systems. This is because they allow for transmission of both data and current from stationary devices to rotating devices. Slip rings can be found in almost all pieces of machinery that are equipped with rotating devices, which in turn requires data connectivity and power. It is for this reason that electrical slip rings greatly influence the performance, operation and reliability of equipment. These amazing electromechanical devices can be used in an array of applications i.e. robotics, directional drilling machines, industrial automation equipment, wind turbines and semiconductor production equipment.
The function of electrical slip rings is to provide an electrical connection thus enabling transmission of both data or current (electrical power) from stationary machines to rotating ones. This means that it is a physical contacting technique that has replaced cables, it is beneficial because cables would twist and break inside rotating devices.
The 5 major components that make up electrical slip rings are ball bearings, housing, sliding contact (brush), rotor and conductor. The work of the brushes is to facilitate a sliding contact with a conductor ring thus establishing a rotating electrical connection. It is on the rotor that the conductor ring is mounted. Electrical connections to both sides of the slip rings are provided by lead wires that are internally attached to the conductor ring and the brush. Some options of external electrical connections are connectors, lead wires as well as terminal blocks.
The type of brush or the sliding contact ranks highly when it comes to the selection of a slip ring. There are a number of design parameters that have to be considered when selecting a transmission technology based on signal and power requirements. Some of them include impedance, bandwidth, resistance variation, operating temperature, rotational speed, voltage and current.
Generally, there are 3 kinds of brushes or sliding contacts that are available for those who are interested to buy slip ring brush, they are as follows:
- Composite graphite.
It should be noted that not all manufacturers of slip rings will offer all these 3 brush technologies when you buy a slip ring brush.
Composite brushes are constructed using carbon graphite material. However, it can be mixed with other kinds of metals to enhance the current density. The main use of this type of brush technology is to power motors of higher current applications.
Wire brushes made of monofilament precious metal are mainly utilized in applications of lower current. These are usually characterized by low contact resistance as well as clean signal transmission.
Polyfilament brushes made of precious metal are utilized in applications which demand for multiple contacts for every channel. This in addition to low brush noise and low contact resistance. The target applications in this case are real-time control, high data rates and highly sensitive analog signals.
The above insightful information clearly shows what slip rings are, what they are made of and how they work. These are fundamental electromechanical devices that are widely applied in most modern industries and by extension to various applications.
If you are looking for Industrial slip ring, the author of this article suggests Moflon Technology.