On June 2004, the total number of shipments of YASKAWA’s AC servomotor shipments reached
4 million units since August 1984 of its release to the market as the leading servo drive company.

Sigma-III series

1.Background
The number of shipments on the AC servomotor increases dramatically.
For example, it took 9 years for the achievement of 1,000,000 by 1993, 5 years for the achievement of 2,000,000 by 1998, 3 years for the achievement of 3,000,000 by 2002, and finally 2 years for the achievement of 4,000,000 by 2004.　

2.Market Extend
The servomotor was introduced for textiles, machine tools, robotics, food, packaging, and printing since its release in 1984. However servomotors generally began to be recognized for their efficiency for semiconductor processing and electronic parts mounting. Today the machine loaded AC servo drive is showing an increase in requests for pressing, which requires a great deal of power, and the injection molding machine with a high degree of accuracy and energy savings.
In the AC servo drives, the demand is increasing for network capable devices for reducing wiring and management of device information.
Thus the market will show a significant increase in scale in the future.　

3.Development
YASKAWA has produced progressive items for the market and pulled the true value out of the machine, and supplied products that satisfy customer needs in the AC servo drive market.
On September 1992, YASKAWA released Sigma series for the first time in the world; small size, high frequency, high accuracy positioning, and simple operation with the concept of small, quick, and easy.
On September 1997, Sigma-II series was released to broaden the series, to elevate the basic efficiency of the machine by embarking on new technology such as the serial encoder, and to meet customer needs.
On March 2002, Sigma-III series was released to demonstrate the extreme efficiency with every use, and in order to provide the solutions for the customer with the new point of view.　

In 2000, as the application of the AC servo drive, Linear Sigma series; linear drive AC servo drive was released. In 2001, Direct drive Sigma series; direct drive AC servo drive, and then in 2003, Sigma-Trac-µ; high accuracy and thin-type linear slider. There are other types of servo drives that differ from the general type of rotating machine.　

We always keep abreast of the market which allows us to offer a wide range of motor specifications, setting up production in the most suitable places in Asia, China, America, and Europe with a global and substantial service network to meet customer needs. Another highly evaluated aspect of our servo drive product line is that they conform to CE, UL and cUL standards. We also practice lead-free manufacturing in consideration of the environment.
We continue to produce new and high-value products to meet the ever expanding demands of the growing marketplace.　

[Reference]
Specification of the Sigma-III series

*One-parameter tuning
One-parameter tuning enables some servo gains to be set best and short by manipulating one auto-tuning level.