Moog D633-A Series, User Manual

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3 Product Description Function and mode of operation
© Moog GmbH User Manual "D633-A Series" (CA80942-001; Version 1.0, 12/08) 12
3.1.2 Permanent magnet linear force motor
Representative depiction
of a permanent magnet
linear force motor
Figure 2: Representative depiction of a permanent magnet linear force motor
Permanent magnet linear
force motor
A permanent magnet linear force motor ( figure 2 or item 10 in figure 1 ) is used
to drive the valve spool (item 8 in figure 1 ).
In contrast to proportional-solenoid drives, the permanent magnet linear force
motor can move the spool from the spring-centered center position in both
working directions. This results in high actuating power for the spool simulta-
neously with very good static and dynamic properties.
The permanent magnet linear force motor is a differential motor excited by per-
manent magnets. Some of the magnetic force is already provided by the per-
manent magnets. The linear force motor’s power demand is thus significantly
lower than is the case with comparable proportional solenoids.
The linear force motor (
figure 2 or item 10 in figure 1 ) drives the valve spool
(item 8 in figure 1 ). The spool starting position is determined in the de-ener-
gized state by the centering springs (item 5 in figure 2 ). The linear force motor
enables the spool to be displaced from the starting position in both directions.
Here, the actuating power of the linear force motor is proportional to the coil
current.
The high forces of the linear force motor and centering springs effect precise
spool movement even against flow and frictional forces.
3.1.3 Signal interfaces
The valves are provided with a valve connector X1 for the command signal.
Pin assignment of valve connector X1:
Ö
Chapter "8.2 Valve connector X1", page 43
Item Designation
1 Coil
2 Bearing
3 Armature
4 Permanent magnets
5 Centering springs
6 Screw plug