PLATE 1475519 - Caterpillar

Illustration 1 g03599537
(5) Accumulator
(16) Line (pilot oil from pilot oil manifold)
(17) Mounting block The accumulator stores pilot pressure oil for use at the main control valves. During some operations, the pilot system needs more oil because there is insufficient flow from the pilot pump. Accumulator (5) will provide pilot pressure oil to the pilot system when the pilot pump flow is inadequate. Insufficient supply of pilot oil flow to the pilot system may be caused by the following two reasons:
Implements are lowered while the engine is stopped and oil supply to the main control valves is stopped.
Combined operations
Illustration 2 g03664927
Accumulator
(5) Accumulator
(16) Line (pilot oil flow from pilot oil manifold to the mounting block for the accumulator)
(17) Mounting block
(18) Passage
(19) Inlet port
(20) Pressure oil chamber
(21) Vessel
(22) Bladder
(23) Gas chamber The pilot oil also flows through line (16) to the mounting block for the accumulator. The pilot oil now flows through passage (18) and inlet port (19) into pressure oil chamber (20). The pilot oil acts against bladder (22) and the nitrogen gas in gas chamber (23) is compressed. Check valve (29) prevents a backflow of the stored oil in the accumulator. The stored oil is used for solely operating the stems of the main control valve.