A.1.2 Directly-Controlled Servo Solenoid Valves, Sizes 6 And 10 - Siemens Sinumerik 840D Series Function Manual

10.03
A.1.2 Directly-controlled servo solenoid valves, sizes 6 and 10
Mechanical
structure
Size 6
7-pin connector
Reset spring Valve spool
Steel sleeve
Fig. A-13 Directly-controlled servo solenoid valves, sizes 6 and 10 (Rexroth)
 Siemens AG, 2003. All rights reserved
SINUMERIK 840D/SIMODRIVE 611 digital, HLA Module (FBHLA) - 10.03 Edition
The standard series of Bosch Rexroth size 6 and 10 servo solenoid valves
shown in the following diagram are based on the same principle.
The valve spool in its steel sleeve is pushed against the reset spring directly by
the actuating solenoid. The armature axis of the solenoid is mechanically
coupled to the ferrite core of the position sensor integrated in the solenoid.
This sensor is a proximity-type, wear-resistant differential transformer ( LVDT).
The housing of the integrated valve amplifier (On Board Electronic OBE) is
bolted directly onto the solenoid/position sensor module.
Electrical power is supplied and the setpoint injected via a 7-pin connector.
If the valve is operating around the mid-position, the solenoid is energized by
about 50%. When the power supply is switched off, it assumes a 4th position,
known as the fail-safe position. On connection and disconnection of the supply,
it slides through the crossed position.
The valves are available with a variety of nominal flow rates and two different
fail-safe positions.
Valve amplifier
Actuating
solenoid
Actuating
armature
solenoid coil
A.1 Servo solenoid valves
Size 10
O
P
O
P
LVDT coils
LVDT ferrite core
A Hydraulics
Fail-safe open
B
T
Fail-safe closed
B
T
A-247