SUPPORT AS 1866437 - Caterpillar

Illustration 1 g03853983The accumulator charging valve is located on the left side of the front frame, in the transmission compartment.
Illustration 2 g03075237
Accumulator charging valve
(1) Inlet from the brake and pilot pump
(2) Outlet to the transmission oil cooler hydraulic fan motor
(3) Plug
(4) Accumulator port for the front brakes
(5) Outlet to the hydraulic tank
(6) Port for the brake accumulator oil pressure sensor
(7) Accumulator port for the rear brakes
(8) Pressure relief valve
(9) Adjustment screw for cut-in and cut-out pressures
(10) Flow control valve
(11) Standby pressure spring The brake and pilot section of the gear pump supplies hydraulic oil to the braking system. The oil first flows to the brake accumulator charging valve. The accumulator charging valve maintains the pressure in the brake accumulators at a constant range while the engine is running.The inverse shuttle section of the accumulator charging valve senses the lower pressure of the two accumulator pressures. The oil then flows from the inverse shuttle section of the accumulator charging valve to the brake accumulator oil pressure sensor.A spool in the accumulator charging valve then moves in order to allow the hydraulic oil to flow to one accumulator or to both accumulators. In addition, the brake and pilot section of the gear pump supplies oil to the parking brake circuit, the hoist pilot circuit and the steering pilot circuit. The excess oil which is not required for these systems flows to the hydraulic fan motor for the transmission oil cooler.
Illustration 3 g03077278
Schematic for the accumulator charging valve
(1) Inlet from the brake and pilot pump
(2) Outlet to the transmission oil cooler hydraulic fan motor
(4) Accumulator port for the front brakes
(5) Outlet to the hydraulic tank
(6) Port for the brake accumulator oil pressure sensor
(7) Accumulator port for the rear brakes
(8) Pressure relief valve
(10) Flow control valve
(11) Standby pressure spring
(12) Orifice for controlling the rate of oil charge to the brake accumulators
(13) Check valve
(14) Spool for cut-in and cut-out pressure
(15) Inverse shuttle valve The accumulator charging valve contains the following internal components: a pressure relief valve, a flow control valve, a flow control orifice, a spool for cut-in and cut-out pressure and an inverse shuttle valve.The accumulator charging valve controls the flow of oil from the brake and pilot section of the gear pump to the brake accumulators. Pressure relief valve (8) limits the oil pressure that flows from the brake and pilot section of the gear pump to the braking circuit.Flow control valve (10) regulates the flow of oil to the braking circuit. The excess oil not required by the pilot circuit or the braking circuit is diverted to the hydraulic fan motor for the transmission oil cooler.Note: Flow control valve (10) contains shims that set the stand-by pressure of the brake and pilot pump. When the pump is at stand-by pressure, the brake accumulators do not require charging.Check valve (13) prevents oil from flowing through the accumulator charging valve, and back to the brake and pilot pump.Spool (14) is for controlling the cut-in and the cut-out pressures for the accumulator charging valve. When the