servovalves | Pneumatic
servovalves | Servo Electronics
Hydraulic R-DDV servovalves
The HR Textron R-DDV servovalve is a unique,
high performance and rugged servovalve. A revolutionary design approach
incorporates an electronically controlled,
permanent magnet brushless dc motor to drive a single stage spool valve.
This innovation results in superior reliability and outstanding servo
performance at a price comparable to traditional servovalve designs. The
R-DDV servovalve has been proven in thousands of applications and
is available in hydraulic flows to 60 gpm.
How It Works
In simplest terms, a limited angle brushless dc torque motor drives a
valve spool directly through an "eccentric" built into the motor
shaft. Rotary motion of the motor shaft results in motion of the spool,
which in turn modulates fluid flow through the valve control ports.
R-DDV servovalve incorporates an integrated electronic
controller with sophisticated control algorithm, which is packaged into
the motor enclosure. The controller compares the electronically monitored
spool position with the input command signal. The resulting error signal
is amplified to produce a current, which drives the motor to the commanded
position. The signal is electronically enhanced to give optimum valve
performance hysteresis, linearity and internal leakage are minimized
while dynamic performance and stability are optimized.
The R-DDV servovalves are single stage devices. There
are no fluid amplifiers or first
stage pilot valves. Therefore, R-DDV servovalves operate independent
of supply pressure -- and there are no orifice assemblies, nozzles, jets
or filters which are subject to contamination, wear or maintenance. Robust
design features ensure excellent tolerance of pressure spikes as well
as mechanical shock and vibration.
The reliability inherent in the R-DDV servovalve design
is evident from the consistent, trouble-free operation in many critical
and demanding industrial applications.
Four hydraulic models are available. Review the specification information
at this web site, then contact Flow
Products, Inc. at 800-631-2029 to review your specific application.
Model 27A : up to 3.5 gpm @ 1000 psid
Model 27C : up to 10.5 gpm @ 1000 psid
Model 27E : up to 15 gpm @ 1000 psid
Model 27G : up to 60 gpm @ 1000 psid