Apr.27, 2007
Minebea Co., Ltd.

Development of the World’s Smallest Diameter*1 Stepping Motor

Minebea Co., Ltd. (hereinafter called “Minebea”) has successfully developed and is set to begin accepting orders for sample shipment of a PM stepping motor with the world’s smallest diameter at a mere 3 mm.

This is followed by the development and sample shipment of a 6mm diameter PM stepping motor with an output power twice as large as our conventional models in high frequency range.

Recent years have seen a rapid increase in the demand for PM stepping motors aimed at small lens actuators for such as digital still cameras. Anticipating such market trend, Minebea has developed a stepping motor with the world’s smallest diameter to aggressively establish a product line that is set to become the industry leader.

The 3mm diameter PM stepping motor is not only the world ‘ s smallest in diameter but achieves superior performance by combining output power sufficient as a lens drive actuator with the successful development of a high precision step drive system.

These models make it possible to design ultra-small camera lens units for rapidly expanding camera cell phone markets and thus enable to design thinner and smaller camera cell phones. They also make it possible to incorporate AF and ZOOM functions easily to achieve high resolution camera units. By introducing these models, we are expecting huge demand for actuator motors in the high-end camera cell phone markets.

Development of these products have been achieved through the development of elemental technologies beyond conventional ones, such as ultra-small diameter magnets with superior performance, precision stator yokes with high saturation magnetic flux density, high-density windings for confined spaces and designs utilizing magnetic and structural analysis.

Minebea is renowned for the development and production of small-diameter PM stepping motors in optical pickup and digital still camera applications, and under a policy bolstering research and development throughout the Minebea Group, development of new products with the potential to become industry leaders is accelerated, for continuous release into the market.

Gradual sample shipment of the world’s smallest (3mm) diameter stepping motor is scheduled to start in June. Sample Price: 30,000 yen.

Sample shipment of the high performance 6mm diameter stepping motor is already underway, with a 500,000 unit per month production setups to be established by the end of the year, and production capacity scheduled to reach 2 million units per month in the next fiscal year.

*1: Minebea estimate as of April 26, 2007

[3mm Diameter Development Model]
External View & Reference Performance

Features & Applications

• World’s smallest diameter/lightest stepping motor
• High output & high performance
• Lens drive for cell phone cameras (A/F)
• Microactuator for various devices

[6mm Diameter Development Model]
External View & Reference Performance

Features & Applications

• Realization of high-performance

1 Twofold increase in pull-in speed compared to conventional Minebea models

2 Minimum starting voltage 50% less than conventional Minebea models

3 step angle error 50% less than conventional Minebea models

• Digital camera lens drive (A/F & Zoom)
• Actuator for various devices

6 mm. diameter stepping motor (left) and 3 mm. diameter stepping motor

For inquiries, please contact:
Minebea Co., Ltd.
Masaki Ishikawa
Corporate Communications Office
Corporate Planning Department
ARCO Tower, 19th Floor,
1-8-1, Shimo-Meguro, Meguro-ku, Tokyo 153-8662
Tel : 81-3-5434-8637 / Fax : 81-3-5434-8607
E-Mail : mishikaw@minebea.co.jp
URL : http://www.minebea.co.jp