SEAT GP 1471117 - Caterpillar

STICK OUT Operation
Illustration 1 g00918393
Simplified hydraulic schematic (stick lowering control valves) (1) Stick cylinders (2) Line (3) Line (4) Check valve (5) Passage (6) Port (7) Check valve (8) Passage (9) Valve (10) Check and relief valve (11) Passage (12) Port (13) Passage (14) Pressure inlet (15) Pilot line (16) Pilot control valve (17) Return line (18) Drain line (19) Line (20) Line (21) Main control valveWhen the operator moves the joystick to the STICK OUT position, the pump oil flows from main control valve (21) through line (20) to ports (14) of the stick lowering control valves. The pump oil flows through check valves (7), passages (5), and ports (6) to the head end of stick cylinders (1). Line (3) connects the stick cylinders. This maintains equal pressure in the head end of the stick cylinders.When the joystick is returned to the NEUTRAL position, the stick cylinder is held in the raised position. Check valves (4), check valves (7), and check valves (10) prevent the oil in the head end of the stick cylinder from flowing out of the stick cylinder.STICK IN Operation
Illustration 2 g00918395
Simplified hydraulic schematic (stick lowering control valves) (1) Stick cylinders (2) Line (3) Line (4) Check valve (5) Passage (6) Port (7) Check valve (8) Passage (9) Valve (10) Check and relief valve (11) Passage (12) Port (13) Passage (14) Pressure inlet (15) Pilot line (16) Pilot control valve (17) Return line (18) Drain line (19) Line (20) Line (21) Main control valveWhen the operator moves the joystick to the STICK IN position, pilot oil is sent through line (15) to ports (12) of the stick lowering control valves. Pilot oil flows through passages (11) to valves (9) and check valves (4). Check valves (4) are opened and valves (9) shift to the right.Pump pump oil flows from main control valve (21) through line (19) and lines (2) to the rod end of the stick cylinders.Oil from the head end of the stick cylinders flows through ports (6), check valves (4), passages (8), valves (9), passages (13), and line (17) to the hydraulic tank.When the joystick is returned to the NEUTRAL position, check valves (4) close and valves (9) shift to the left. The stick cylinder is held in position.