A magnetic MEMS actuator using a permanent magnet and magnetic fluid enclosed in a cavity sandwiched by polymer diaphragms

作者：Imai Satomitsu^*; Tsukioka Tatsuki

来源：Precision Engineering-journal of the International Societies for Precision Engineering and Nanotechnology, 2014, 38(3): 548-554.

DOI：10.1016/j.precisioneng.2014.02.003

• Actuator
• Magnetic force drive
• Permanent magnet
• Magnetic fluid
• Diaphragm
• Polymer
• MEMS

A magnetic microelectromechanical systems (MEMS) actuator using a small permanent neodymiummagnet surrounded by magnetic fluid (MF) was developed and characterized. The magnet is enclosed in a cavity sandwiched by two identical thin PET-sheet diaphragms and is able to move smoothly due to the MF. The diaphragms deflect when an external magnetic force is applied to the magnet. This structure was adopted to prevent the diaphragms from being stiffened by attaching or fabricating a magnetic layer on the diaphragm surface and to secure the necessary volume of magnetic material. The magnets are 2-4 mm in diameter and the cavity is 5 mm in diameter and 1 mm in depth. The diaphragms are 20 mu m in thickness. Experiments showed the displacement amplitude generated at the diaphragm center was in the range of 10-50 mu m for attractive and repulsive magnetic force when magnetic flux density of 4-30 mT was applied. The response was within about 1 s. The deflection profile of the diaphragms can also be varied by changing the magnet position.

• 出版日期2014-7