SUPPORT 1379819 - Caterpillar

Stick In (Fast with Regeneration - Work Tool Suspended)
Illustration 5 g06072157
Hydraulic schematic for STICK IN (fast with regeneration)
(1) Pilot control valve (stick and swing)
(2) Stick cylinder
(3) Line (stick cylinder rod end)
(4) Line (stick cylinder head end)
(7) Passage
(8) Main control valve
(11) Return line
(12) Valve
(13) Stick drift reduction valve
(16) Stick I control valve
(17) Return passage
(18) Check valve
(20) Load check valve
(21) Center bypass passage
(23) Return passage
(24) Parallel feeder passage
(25) Center bypass passage
(26) Check valve
(27) Stick II control valve
(28) Drive pump
(29) Idler pump
(30) Pilot pump
(31) Stick regeneration valve
(34) Pilot line
(36) Pilot line
(38) Pilot line
(39) Passage
(40) Stick unloading valve
(41) Passage
(42) Passage
(43) Passage
(44) Passage
(45) Check valve
(46) Passage
(47) Pilot lineThe 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 head end of stick cylinder (2) is supplied to the rod end of stick cylinder (2). The regeneration circuit makes more effective use of the return oil from stick cylinder (2). This action allows the oil delivery from idler pump (29) and drive pump (28) 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 (1) flows through pilot line (36). The pilot oil flow then divides into several flow paths. Part of the pilot oil flows through pilot line (34) and pilot line (38) to stick I control valve (16). The pilot oil in pilot line (34) also flows through passage (46) in stick drift reduction valve (13). Part of the pilot oil flows through pilot line (47) to stick regeneration valve (31).Since the pilot oil pressure has caused the spool in stick I control valve (16) to shift to the right, the oil delivery from idler pump (29) flows through center bypass passage (21), load check valve (20), stick I control valve (16) and passage (7) to line (3).Part of the oil delivery from drive pump (28) that is in center bypass passage (25) flows through check valve (18) and stick II control valve (27) to passage (7). The remainder of the oil delivery from drive pump (28) flows through parallel feeder passage (24), check valve (26) and stick II control valve (27) to passage (7). All of the oil delivery from drive pump (28) combines in passage (7) with the oil delivery from idler pump (29) and flows to line (3). The combined pump oil flows to the rod end of stick cylinder (2).The return oil from the head end of stick cylinder (2) flows through line (4) to stick drift reduction valve (13). Valve (12) in stick drift reduction valve (13) shifts UP and the return oil enters passage (42). Part of the return oil in passage (42) flows through stick I control valve (16), return passage (17) and return line (11) to the hydraulic tank. The remainder of the return oil flows through the regeneration circuit