COVER AS 4Z9023 - Caterpillar

Stick In (Fast with Regeneration - Work Tool Suspended)
Illustration 5 g03872237
Hydraulic schematic for STICK IN (fast with regeneration)
(1) Stick cylinder
(2) Line (oil flow from stick cylinder rod end)
(3) Line (oil flow to stick cylinder head end)
(4) Pilot control valve (stick and swing)
(6) Main control valve
(7) Return line
(8) Stick drift reduction valve
(9) Stick II control valve
(10) Check valve
(11) Passage
(14) Valve
(15) Check valve
(16) Stick I control valve
(17) Return passage
(19) Center bypass passage
(21) Load check valve
(23) Center bypass passage
(25) Parallel feeder passage
(26) Return passage
(27) Idler pump
(28) Drive pump
(29) Pilot pump
(31) Stick regeneration valve
(33) Stick unloading valve
(34) Passage
(35) Passage
(36) Passage
(37) Passage
(38) Passage
(39) Passage
(40) Pilot line
(41) Pilot line
(42) Pilot line
(43) Check valve
(44) Pilot line
(45) Pilot line
(46) Pressure reducing valve for boom priority The STICK IN operation contains a regeneration circuit. When the work tool is suspended above the ground during a STICK IN function, stick regeneration valve (31) is operational in the stick hydraulic circuit. The return oil from the rod end of stick cylinder (1) is supplied to the head end of the stick cylinder. The regeneration circuit makes more effective use of the return oil from the stick cylinder. This action allows the oil delivery from the idler pump and the drive pump to perform other implement functions during a STICK IN function.When the joystick for the stick is moved to the STICK IN function, pilot oil from pilot control valve (4) flows through pilot line (40). The pilot oil flow then divides into several flow paths. Part of the pilot oil flows through pilot line (41), pilot line (45), and pilot line (42) to stick I control valve (16). The pilot oil in pilot line (41) also flows through passage (35) in stick drift reduction valve (8). Part of the pilot oil flows through pilot line (44) to stick regeneration valve (31). The remainder of the pilot oil flows through pressure reducing valve for boom priority (46) and pilot line (45) to stick II control valve (9).Since the pilot oil pressure has caused the spool in stick I control valve (16) to shift to the right, the oil delivery from the idler pump flows through center bypass passage (23), load check valve (21), stick I control valve (16) and passage (11) to line (3).The pilot oil pressure in pilot line (45) has caused the spool in stick II control valve (9) to shift to the right. Part of the oil delivery from the drive pump that is in center bypass passage (19) flows through check valve (15) and stick II control valve (9) to passage (11). The remainder of the oil delivery from the drive pump flows through parallel feeder passage (25), check valve (10) and stick II control valve (9) to passage (11). All of the oil delivery from the drive pump combines in passage (11) with the oil delivery from the idler pump and flows to line (3). The combined pump oil flows to the head end of stick cylinder (1).The return oil from the rod end of the