How does the slip ring work?
There is a common physical puzzle for all the equipment, namely, when one part of the equipment is continuous rotating, how do the power and the signal transmit from the static part to the rotating part? If the wire directly is connected, that wire will be twisted into a rope.
The solution is the slip ring which is designed as a mechanic and electric precision component. Its another name is called the rotating joint or electrical interface with its core mission for building an "everlasting bridge" between the static and rotating components. And, you can understand the principle of the slip ring that just likes an invisible joint for the rotating equipment. Moreover, in spite of its unimpressive, the slip ring indeed decides whether the equipment can be run with a stable and a long period of operation.
And, the structure of the most advanced slip ring is not complex.
- Ring Body: fixed on the rotating axle with a synchronous rotating conductive ring for the purpose that its each and every channel can respectively corresponding to one circuit.
- The brush: fixed on the static end pressed on conductive contact on the surface of ring body with common materials of graphite carbon brush and precious metal wire.
Once rotating, the brush always remains its sliding contact with the circuit for the purpose of transmitting the current and the signal, which has the story of the origin of the name of the slip ring.
Obviously, there are three regular problems about the sliding contact itself, namely the wear, the contact noise and the life time. Owing to a long period of the operation, the loss will be generated through the friction between the ring and the brush. What's worse, owing to a slight vibration of the contacts, the noise of the transmitted signal will be generated. Since more than half a century, the history of the slip ring has represented the story with its friction.
