DOOR AS-ACCESS 4640294 - Caterpillar

Stick Out
Illustration 1 g00637896
Stick drift reduction valve (STICK OUT) (1) Passage (vent for spring chamber) (2) Spring chamber (3) Spring (4) Solenoid valve (5) Passage (6) Spool (7) Port (oil flow to stick cylinder rod end) (8) Valve (9) Passage (oil flow from stick control valve) (10) Stick drift reduction valve
Illustration 2 g00984040
Main control valve (10) Stick drift reduction valveDuring a stick out operation, oil flows from the stick control valve into passage (9). The oil enters stick drift reduction valve (10) and pushes against spool (6). Since solenoid valve (4) is not energized, valve (8) is pushed downward by spring force. This allows oil to flow from passage (5) and through valve (8) to passage (1). When the oil pressure in passage (9) increases, spool (6) attempts to move to the left. As a result, spool (6) moves to the left against the force of spring (3). The oil delivery now flows from passage (9) to port (7). The oil then flows to the rod end of the stick cylinder.Stick In
Illustration 3 g00637900
Stick drift reduction valve (STICK IN) (1) Passage (vent for spring chamber) (2) Spring chamber (3) Spring (4) Solenoid valve (5) Passage (6) Spool (7) Port (oil flow from stick cylinder rod end) (8) Valve (9) Passage (oil flow to stick control valve) (10) Stick drift reduction valve (11) Drain portWhen the stick control lever is moved for a STICK IN operation, solenoid valve (4) is energized. Valve (8) moves up and passage (1) is open to drain port (11). The oil in spring chamber (2) flows through drain port (11). The oil then flows to the pump suction line.Return oil flows from the stick cylinder rod end to port (7). Since the oil pressure in spring chamber (2) is low, the oil flow from port (7) causes spool (6) to open. The oil now flows from passage (9) to the stick control valve.