The 4/3 directional control valves are designed as direct operated devices in plate design. Operation is effected by means of control solenoids. The solenoids are controlled via integrated control electronics (OBE).
Set-up:
The valve basically consists of:
- Housing (1) with connection surface
- Control spool (2) with compression springs (3 and 4)
- integrated control electronics (OBE) (8)
- Zero point adjustment accessible via Pg9 cover (9)
Functional description:
- With de-energized solenoids (5 and 6), central position of the control spool (2) by compression springs (3 and 4)
- Direct operation of the control spool (2) by energization of a control solenoid
e.g. control solenoid "b" (6)
- Displacement of the control spool (2) to the left, proportionally to the electric input signal
- Connection from P → A and B → T via orifice-type cross-sections with linear flow characteristics
- Switching off the solenoid (6)
The compression spring (3) brings the control spool (2) back into the central position
In the de-energized condition, the control spool (2) is held in a mechanical central position by the return springs of the solenoids. With control spool symbols “V” and “Q”, this position does not correspond to the hydraulic central position! When the electric valve control loop is closed, the control spool (2) is positioned in the hydraulic central position.
4WRSE 10