Slip rings are electromechanical devices that allow the transmission of power and electrical information from a stationary to a rotating structure (or vice versa), making them a crucial part of many rotating systems. They are also known as rotary electrical joints, collectors, or electric swivels, and have many uses across multiple industries. They are generally used in electromechanical systems, including aerospace, defence, and industrial automation systems, that need some level of rotation while transmitting power.
The slip ring maintains a conductive transmission line between the rotor and the shaft. However, there may be a risk of a heat or fire hazard if the power is high. By the beginning of the 2000s, the slip ring manufacturers added a new component for the slip ring brushes: liquid metal mercury, to avoid any such incident. By using this new material in the brushes, the potential of a heat or fire hazard is greatly reduced.
The mercury-wetted slip rings that conduct massive levels of electricity amounts without posing a serious fire or heat hazard are called pneumatic slip rings.
How the Slip Ring Works
Rings and brushes make up the two primary components of a slip ring. Electrical energy is transferred through contact between the rotating ring and the stationary brushes.
The ring is built using an electrically conductive metal, such as coin silver, brass, or silver. Usually positioned on a centre shaft, this part provides the circuit path.
The brushes provide electrical contact and connect the rotating and stationary components by sitting on arms that are fastened to the side posts that ride on the ring. They are constructed from a variety of conductive materials, including copper graphite and silver graphite.
Depending on the use, slip rings can rotate at a wide variety of speeds. The slip ring is mounted on a base plate and moves along a centre shaft. While the shaft spins in the centre, the base plate is kept still. This completes the circuit by enabling the slip ring to transmit electrical power from a fixed system to a 360-degree rotating component.
Slip rings are frequently found in electric motors, generators, wind turbines, and radar antennas, where they are essential for maintaining continuous rotation.
For electric motors, slip rings allow electrical signals and power to be transmitted to the rotor, which is necessary for the motor to function properly.
Slip rings also permit the rotation of radar antennas without interfering with the electrical signal transmission. For generators and wind turbines, they transfer electricity from the revolving blades to the stationary generator.
Machinery and equipment for industrial automation also use slip rings for various applications. They are also frequently utilised in automated assembly lines and packaging equipment, where the system’s optimal operation necessitates continual rotation.
How Does the Pneumatic Slip Ring Work
A slip ring is constructed from a few electrically conducting materials that are kept concentrically encircling a shaft. It enables the transmission of electricity and signals between a machine’s spinning component and a stationary component using the brushes.
While the functioning is quite similar, one of the key differences is that a pneumatic slip ring is fixed to one of the ends of a rotating shaft, coaxial with that of a rotational axis.
Pneumatic slip rings can also be used to transfer fluid using pressure or vacuum. The use of a pneumatic slip ring preserves and isolates the fluid connection while rotating 360 degrees by transferring the pneumatic pressure or vacuum from a stationary inlet to a spinning outlet.
What Types of Fluids can Be Transmitted Using a Pneumatic Slip Ring?
Pneumatic slip rings can transmit a wide variety of gases and liquids. Air, water, and hydraulic oil, among many other things, are examples of this. The particular fluid depends on the use and system requirements.
Can High-pressure Applications Employ a Pneumatic Slip Ring?
Absolutely. Pneumatic slip rings can be made to resist high-pressure applications and operate well in them. Based on the pressure and temperature requirements of the system, seals and other materials are selected.
What Advantages Can Pneumatic Slip Rings Offer?
The advantages of pneumatic slip rings are numerous. The ability to rotate continually without tangling or breaking, the ability to transport various gases or fluids at once, and the ability to do so without contamination or leakage are a few examples of these.
Which Industries Commonly Use Pneumatic Slip Rings?
Several different industries use pneumatic slip rings frequently. The use of robots and automation, as well as aeronautical and medical technology, are a few of the more notable examples. They are widely employed in systems including robotic end-effectors, rotating medical devices, food processing equipment, and fuel transfer for aeroplanes.
What Distinguishes a Pneumatic Slip Ring from a Hydraulic Slip Ring?
While a hydraulic slip ring moves fluids using hydraulic pressure, a pneumatic slip ring moves gases or fluids using air pressure. To withstand the pressure and temperature requirements of the system, the two different types of slip rings employ multiple seals and materials.
The pneumatic slip ring is superior to the traditional slip ring in a number of ways. It has many qualities that make it preferable to slip rings. Comparatively speaking, pneumatic slip rings require much less maintenance than traditional slip rings. They feature a more compact construction that fits neatly into any system. Also, it offers a smoother and simpler installation than the somewhat complicated standard slip ring. Pneumatic slip rings perform more efficiently than regular slip rings when there is a high current flow and speed.
Moreover, the pneumatic slip ring is ideal than a traditional slip ring for signal transmission and current management because it mercury is both liquid and conductive.
Pneumatic slip rings can be tailored to satisfy special needs for a certain application, including the working speed, temperature and pressure range, and level of needed environmental protection. These are highly adaptable and customizable because they come in a variety of sizes, forms, and materials.
Overall, pneumatic slip rings provide a dependable, effective, and affordable option for power, signal and fluid transmission in rotary applications across several industries.