Design of a Rectangular-Type Voice Coil Actuator for Frame Vibration Compensation

Abstract

Precision motion stages used in the manufacturing process of flat-panel displays have inevitably low settling performance due to their huge mass and bulky structures. In order to improve the settling performance, several methods of frame vibration compensation have been developed so far. These methods are used to cancel the vibration by imposing a counter force or modifying the resonance mode of the frame of the stage. To compensate the frame vibration, high force actuators are required. In this paper, a mighty voice coil actuator is proposed to generate the counter force against the frame vibration. The proposed voice coil actuator has an axis-symmetric rectangular structure to achieve a large force with simple and low cost fabrication. Also, the voice coil actuator allows radial clearance up to ± 4 mm. Using an optimized design process and a magnetic circuit model, the power consumption is minimized while the required force is obtained. With a power of 322 W, the VCA has been designed to have a maximum force of 574 N with a force constant of 164 N/A. Experimental results verified the force constant of the fabricated voice coil actuator is well matched with the designed value.

Analysis of High Force Voice Coil Motors for Magnetic Levitation

“…Here, a yoke is attached to the upper and lower sides to concentrate the magnetic flux in the air gap. Figure 1b shows the rectangular type axis-symmetric VCM developed by Choi et al [17], in which four pairs of magnets are arranged in an external yoke, while an internal yoke that is sufficiently thick to prevent magnetic saturation is positioned in the center. Two upper and lower coils are wrapped around the internal yoke.…”

“…Zhang and Meng studied a VCM composed of a double-sided magnet pair for a maglev device [11]. Choi et al [17] and Ahn et al [12] proposed a VCM with an axial symmetric rectangular structure that can produce considerable force, studied the optimal design method, and tested its mechanical and electrical characteristics. Lee et al [18] optimized the shape of the permanent magnet and yoke by considering the magnetic saturation effect in order to maximize the force of a VCM with a steel and permanent magnet.…”