Linear Actuator with Moving Magnet Offers Precise Positioning
HSMAG Magnetics’ new Moving Magnet Voice Coil Actuator series allows for precise positioning to meet high accuracy requirements. When combined with smart drive electronics, this actuator can be controlled for speed and desired output force. HSMAG expertise in design of magnetic field circuits has resulted in a high efficiency design which translates to high performance for precision applications. By keeping the magnet mass low, the system inertia is well controlled resulting in more precise speed and position control.
Moving magnet actuators lend themselves to applications that require moderate speed and controllable, gentle stop points, functions not achievable with solenoids or standard voice coil actuators. Typical applications include remotely controlled circuit breakers, medical hand tools and other delicate instrumentation.
Unlike standard voice coil actuators where the magnet assembly is intended to remain fixed while the coil assembly moves, HSMAG ’s Moving Magnet Voice Coil Actuators are designed to use a stationary coil. In addition, having a stationary coil allows for a simpler design of the electrical connections.
“Not every application is about speed,”said Jim Zhang, HSMAG Senior Applications Engineer. “And in those applications, the Moving Magnet Voice Coil Actuator really shines. It can move at just the speed needed with a controllable, gentle stop.”
Electrometallurgy involves metallurgical processes that take place in some form of electrolytic cell. The most common types of electrometallurgical processes are electrowinning and electro-refining. Electrowinning is an electrolysis process used to recover metals in aqueous solution, usually as the result of an ore having undergone one or more hydrometallurgical processes. The metal of interest is plated onto the cathode, while the anode is an inert electrical conductor. Electro-refining is used to dissolve an impure metallic anode (typically from a smelting process) and produce a high purity cathode. Fused salt electrolysis is another electrometallurgical process whereby the valuable metal has been dissolved into a molten salt which acts as the electrolyte, and the valuable metal collects on the cathode of the cell. The fused salt electrolysis process is conducted at temperatures sufficient to keep both the electrolyte and the metal being produced in the molten state. The scope of electrometallurgy has significant overlap with the areas of hydrometallurgy and (in the case of fused salt electrolysis) pyrometallurgy. Additionally, electrochemical phenomena play a considerable role in many mineral processing and hydrometallurgical processes. Source: en.wikipedia.org/wiki/Extractive_metallurgy
Unfortunately, most of the world’s capacity for turning oxides into metals resides in China. Through years of research, development and production experience, China has become, in many ways, the technology leader for rare earth processing and refining. There are some additional fused salt electrolysis facilities in Laos and Vietnam, but these are also supported by the Chinese. You can produce rare earth metals from oxides via reduction, but this method does not work as well. By maintaining its hold on the fused salt electrolysis process, in addition to its dominance in mining and magnet production, China can manipulate and control the prices for rare earths. Certainly having oxides from non-Chinese sources is helpful, but until the ability to convert these oxides into metals is readily available outside of China, the rest of the world is not independent.
Certainly, the description above won’t allow you to run out and make your own neodymium metal. The process is technically challenging, requires high amounts of energy, and produces environmentally challenging by-products. In sum, it’s not something you really want to try in your garage or back yard.