For challenging applications like semiconductor fabrication, pick-and-place machines and biomedical equipment, you may have to move loads short distances with a high degree of accuracy. In these situations, it can be easy to simply specify traditional ball screw- or lead screw-type bearings. However, an often overlooked option — voice coil motors (VCMs) — typically can deliver small displacements with precision and repeatability at an attractive cost — often in special environments. This blog post will describe the advantages of VCMs, using Akribis Systems products as examples.

Consisting of only a magnetic housing and coil, VCMs have a simple, single-pole design that does not require commutation. VCMs are also easily controllable by adjusting their voltage polarity and current flow. They also feature low inductance and a low moving mass to deliver high speeds and accelerations. Additional benefits include low hysteresis and compact size. Here’s how VCMs are used in semiconductor, biomedical and automated equipment:

  • Semiconductor fabrication. VCMs are very adaptive for short-distance travel. Applications include enabling small, yet fast movements in lithography, vibration control and cancellation, and adjusting the focal length of optical components in wafer inspection equipment, to name a few. And, their high speeds are especially desirable for board and wire bonding and pick-and-place equipment. In fact, some Akribis VCMs can accelerate to as much as 200 g-forces. And, unlike ball or lead screws, many voice coil motors can operate in vacuums and clean environments without outgassing or contamination.
  • Biomedical equipment. VCMs offer biomedical equipment designers greater accuracy than a traditional direct drive motor, but at a lower price point. They can also fit crucially small size requirements of ever-shrinking devices. In addition, their low hysteresis makes them ideal for dispensing light materials. When combined with an encoder, a VCM can provide extremely accurate force and placement down to micrometer levels.
  • Automated manufacturing. The same high-speed capability that makes VCMs attractive for semiconductor fabrication also makes them desirable for automated processes like pick and place, feeding as well as inspection applications that require precise lens autofocusing.

Permanent Magnet Direct-Drive Motor Technology Benefits
At Akribis Systems, our high-performance VCMs cover a broad range of sizes and force densities. These devices leverage permanent magnet direct-drive motor technology to provide a high power to mass ratio, high acceleration and response, low to no hysteresis and zero cogging. And, they prevent wear and tear because the coil does not make contact with the moving core. Customers can choose our AVM Series standard VCM or the AVA Series with a planar design for tight spaces.

For applications requiring high continuous peak force capability, we also offer voice coil stages featuring our brushless AUM linear motors that provide exceptional stiffness, fast accelerations and fast settling times in a compact unit. Our VCMs can be customized to meet your size and force requirements or include integrated sensors for highly accurate force feedback. Voice coil stages may be outfitted with crossed roller bearings (CRBs) to ensure sub-micron resolution. Akribis Systems technical experts can help you determine the best VCM, voice coil stage or custom unit for your application.

For more information, please visit our product pages for VCMs and stages.