What Is the Function of a Slip Ring? Using sliding electrical contacts, a slip ring transmits electrical signals and power over a revolving interface. These contacts are generally made up of a revolving ring and a stationary brush, or wiper, that glides down the surface of the ring as it rotates. When the brush makes contact with one of the rings, an electrical circuit is formed.
Why Do We Need Slip Ring Connectors? A slip ring connector is used in situations where a rigid cable cannot be used because it would get in the way or block an opening. For example, a slip ring connector is needed when using a mouse on a plane because a normal cable would get in the way as it would dangle behind the mouse. Also, a connector is needed when using a mouse in a tunnel because a cable could not be inserted into the controller. Finally, a slip ring connector is required when using a remote control car because there is no way to connect the car to a cable.
There are two types of slip ring connectors: magnetic and solid-core. The type used depends on what kind of signal must be transmitted. If a simple "on"/"off" signal is needed, a magnetic switch can be used. This type of connector uses a magnet to make or break contact between the rotating and static parts. A more complex signal such as those found in modem communications requires a solid-core connector.
A slip ring is an electromechanical device that permits power and electrical signals to be transmitted from a fixed structure to a revolving structure. A slip ring can be utilized in any electromechanical system where rotation is required while delivering power or signals. Slip rings were originally used on aircraft to transmit electricity from a stationary source (such as a generator) to rotating components (such as engine magnets). Modern versions are used, for example, in satellite communication systems and particle accelerators.
The slip ring assembly consists of two rings, called the inner and outer rings. These rings are usually made of copper or aluminum and have short sections where they overlap each other. They are fitted together so that they cannot come apart. The space between the rings is called the air gap. Power is transmitted into the motor by means of brushes which touch the inner and outer rings. The brushes may be mounted on pivoting arms which allow them to move away from and back towards the shaft when required. An electromagnetic mechanism may be used instead. When current is passed through the coil the magnetic field produced by this current causes the arm to become magnetized and hold its position even when the current is off. This allows the brush to stay in contact with the ring while the motor is running but not when it is not moving, thus preventing energy loss due to friction.
Slip rings are made up of a stationary graphite or metal contact brush rubbing on the outer diameter of a spinning metal ring. The electrical current flows through the stationary brush to the metal ring while the metal ring spins, forming the connection. Slip rings can transmit signals at high speeds because there is no physical contact between the brush and the ring.
This type of transmission system was first used in radar sets where continuous rotation of the set's antenna would be required to scan the radio frequency spectrum. A second use for a slip ring is as part of an active connector on a suspension line of a helicopter. When the connector is mated with another connector on the vehicle or aircraft body, power is transmitted to the rotor blades through the slip rings.
A third use for a slip ring is as part of an external atmospheric pressure sensor on an airplane. When a change in altitude occurs, the ambient air pressure changes which causes the rubber seal inside the sensor to expand or contract. This in turn moves a metal plate which in turn presses against the stationary brush inside the sensor's casing. The electrical signal being detected is sent to a display panel through wires attached to the casing.
The fourth use for a slip ring is as part of an ignition key for an automobile.
A slip ring is a type of electrical connector that connects a fixed item to a revolving assembly. These are employed in a variety of industrial automation applications and for equipment such as tower and jib cranes, as well as cable and hose winders, where a section can spin freely while the base remains stationary. The slip ring allows electricity to be transmitted from the stationary part to the rotating part.
Electric power transmission lines use various methods to transmit electric power from one location to another. For long-distance transmissions into or out of regions served by a single utility company, direct current (DC) is usually used because it requires only one conductor per line instead of an alternating-current (AC) system which uses two conductors: one for positive voltage and one for negative voltage. DC current is also more efficient than AC current at lower voltages because there is no need to convert energy into magnetic fields or back again. For shorter distances or when dealing with small amounts of power, however, AC transmission is often used because it is more practical given the limitations of electrical wiring infrastructure. In fact, most large-scale power transmission systems use AC because it is much easier to manage safely across great distances than would be possible with DC.
The term "slip ring" comes from the fact that these connectors function by having an electrically conductive ring rotate with the body to which it is attached while an insulated plug or jack screws into or out of the ring.