GEAR 9W7765 - Caterpillar

Illustration 1 g00329443
The HOLD Position is Shown. (3) Pivot plate (4) Detent balls (5) Plunger assembly (6) Plunger assembly (7) Plunger (8) Nut (9) Centering springs (10) Washer (11) Spring (12) Plunger (13) Metering springs (14) Passage to tank (15) Springs (16) Metering stem (17) Metering stem (18) Work port (19) Pressure oil port (20) Work port (A) QUICK-DROP position (B) LOWER position (C) HOLD position (D) RAISE positionWhen the pilot valve is in HOLD position (C) , centering springs (9) , (15) and detent balls (4) keep pivot plate (3) in the center position. Springs (15) hold up metering stems (16) and (17) . This allows work ports (18) and (20) to vent to the oil tank. There are orifices in work ports (18) and (20) in order to provide stability in the valve group. When the pilot valve is in RAISE position (D) , pivot plate (3) causes plunger assembly (6) to move down. Plunger assembly (6) will force down plunger (12) , collapsing metering spring (13) and spring (15) . This will allow metering stem (16) to shift. Also, this will allow oil from pressure oil port (19) to flow out of work port (20) .When the pilot valve is in LOWER position (B) , pivot plate (3) causes plunger assembly (5) to move down. Plunger assembly (5) will force down plunger (7) , collapsing metering spring (13) and spring (15) . This will allow metering stem (17) to shift. Also, this will allow oil from pressure oil port (19) to flow out of work port (18) .When the pilot valve is in the QUICK-DROP position (A) , nut (8) pushes down on washer (10) . Washer (10) retracts spring (11) . This pushes down metering stem (17) even further.
Illustration 2 g00389437
(21) Port that receives oil from the quick-drop (22) Spring (23) Plunger (24) Port that returns oil to the hydraulic oil tank (25) Port that receives oil from the pilot valveThis allows pressure to build up in port (25) and this pressure acts against plunger (23) . When plunger (23) pushes spring (22) , a passage will open for the oil to flow from port (21) to port (24) . Then, the oil flows out of port (24) to the hydraulic oil tank.