Moog's New pQ-Servo-Proportional Valves With Fieldbus Communication (D941 Series)

East Aurora, N.Y. - Moog Inc. has introduced a new Digital Interface Valve, with microprocessor based electronics and a CANopen field bus that is ideal for pressure control and pressure limiting applications. This new valve replaces analog technology and offers configurable functions that enable customers to define the dynamic behavior of the valve and adapt its characteristics to particular application requirements, while providing high-precision digital flow and pressure control. This valve is the latest in Moog's ongoing initiative to extend digital intelligence to its most advanced hydraulic and electric motion control products.

This D941 Series Servo-Proportional Valve has integrated electronics and optional analog/digital inputs and outputs. The product is available in 8 lpm [2.1 gpm], 30 lpm [ 7.9 gpm], 60 lpm [15.8 gpm] and 80 lpm [21.1 gpm] flow versions at Äp = 5 bar [75 psi] per land. Some of its key features are the ability to parameterize the valve characteristics, (i.e. electrical null calibration, dead band compensation, flow gain, flow limits, etc.) and tune the pressure loop via a user friendly Windows® based interface. This valve is also operational with only 25 bar pilot pressure, which makes it an ideal design for robust proportional control for low-pressure systems.

Key benefits of the new Digital pQ Servo-Proportional Valves for customers are:

• CANbus Communication: Diagnostic capabilities, integrated monitoring of key environmental and internal characteristics, and valve parameter modifications can be accessed on-site or remotely.

• Flexiblity: The ability to download parameters via the field bus connection or directly from the upper PLC program enables optimum tuning of valve parameters during the machine cycle, even while the machine is operating.

• Superior Control: The improved frequency response of this design allow highs spool position loop gain, providing excellent static and dynamic response and superior control system performance. The improved valve dynamic performance is due to the extremely high natural frequency of the ServoJet® pilot stage (500 Hz) and the implementation of advanced current control algorithms, which is only possible via digital electronics.

• Energy Savings: Considerably improved flow recovery (more than 90% of the pilot stage internal leakage flow) contributes to energy savings, especially for machines with mulitiple valves.

• Reliability: The high pressure recovery of the ServoJet pilot stage (more than 80% delta p at 100% command signal) provides higher spool driving forces and ensures enhanced spool position repeatability.

• Safety: Fail-safe versions with defined safe spool position using a spring, a poppet valve or by external supply cut off ensure operator safety.

• Cost Savings: Since the pressure control loop is tunable via software, rather than passive electronic components, it is now possible to stock a single valve for multiple applications reducing the need to stock several valve models.

"The digital PQ valve is truly a game changer in the hydraulics industry," commented David Fijas, Deputy General Manager of Moog Inc.'s Industrial Controls Division. "This product continues Moog's technological leadership by extending the implementation of digital intelligence across our product lines that results in improved performance, cost, and ease of use for our customers."

Moog is a worldwide designer and manufacturer of performance-based customized motion control solutions utilizing both hydraulic and electric technologies. Our components and systems are used in a variety of machinery applications such as plastics, metal forming, and power generation. Moog Industrial, with sales in 2004 of 282 million USD and 21 locations worldwide, is part of Moog, Inc. (NYSE:MOG.A and MOG.B). For more information visit www.moog.com/industrial.

Source: Moog