ROD 1143936 - Caterpillar

Illustration 1 g00730151
(1) Vent line for the quick-drop valve (2) Spring (3) Orifice in quick-drop valve (4) Quick-drop valve (5) Opening from the line to the main control valve (6) Carry-check valve (7) Passage to rod end of bowl cylinder (8) Spring (9) Orifice in carry-check valve (10) Passage to head end of bowl cylinder (11) Opening from the line to the main control valve (12) Check valve for venting the oilWhen the main control valve is in QUICK DROP position, oil enters the carry-check and quick-drop valve from opening (11) and flows through passage (10) to the head ends of the bowl cylinders. Oil from the spring cavity of carry-check valve (6) is vented to the tank through check valve (12). Oil from the rod end of the bowl cylinders enters the carry-check and quick-drop valve through passage (7) and this oil compresses spring (8). This allows oil to flow to the main control valve through opening (5). This oil passes through the main control valve and flows to the tank.When the main control valve is in RAISE position, oil enters the carry-check and quick-drop valve from opening (5). Check valve (12) is blocked at the main control valve. When the oil pressure from opening (5) overcomes the spring pressure of check valve (6), a small amount of oil from the spring cavity of check valve (6) passes through orifice (9) to passage (7). This allows carry-check valve (6) to open. Oil flows from opening (5) to the rod ends of the bowl cylinders through passage (7). Oil also flows to the quick-drop valve (4). When the pressure in the rod ends of the bowl cylinders overcomes the spring pressure of spring (2), spring (2) is compressed. Oil flows from opening (5) to passage (10) through the large openings in quick-drop valve (4). This oil flows through opening (11) to the main control valve. This oil flows to the tank.When the main control valve is in the LOWER position, oil enters the carry-check and quick-drop valve from opening (11) and flows through passage (10) to the head ends of the bowl cylinders. Oil from the spring cavity of carry-check valve (6) is vented to the tank through check valve (12) and flows to the main control valve. Oil from the rod ends of the bowl cylinders enters the carry-check and quick-drop valve from passage (7) and this oil opens valve (6). Oil exits the carry-check and quick-drop valve through opening (5) and flows to the main control valve. The oil flows through the main control valve and flows to the tank.