摘要 |
A normally closed, electrical solenoid actuated, pressure compensated, proportional, hydraulic flow control valve (4) includes a fluid flow control poppet valve (5), a pilot operator (6), a solenoid operator (7) and a pressure compensator (8). The poppet valve (5) includes a poppet (31) and a seat (32). The pilot operator (6) includes a pilot (36) and a pilot seat (37). The solenoid operator (7) includes a solenoid tube (42) and an armature (44). The pressure compensator (8) Includes a pressure balanced pressure compensator spool (58), a smaller diameter differential pressure compensator control piston (64), and springs (61) that balance the forces on the compensator control piston (64). The compensator control piston (64) moves the compensator spool (58) to maintain a substantially constant pressure differential across the poppet valve (5). The valve (4) may be used in a variety of hydraulic systems. A similar normally opened valve (104) is also disclosed. |