LAMP GP-STOP & TAIL 2433257 - Caterpillar

Illustration 1 g00862474
Brake Accumulator The brake accumulator is mounted in this position on the machine. (1) Outlet Port (2) Pressure oil chamber (3) Piston (4) Nitrogen gas charge (5) Nitrogen charging valveThe 824G Wheel Tractor is equipped with two brake accumulators. One accumulator is for the service brakes on the front axle and one accumulator is for the service brakes on the rear axle.The 825G Soil Compactor and the 826G Landfill Compactor are equipped with one brake accumulator for the front service brakes.Accumulators provide a way to store the pressure oil in the hydraulic circuit. The accumulator will supply the pressure oil to the circuit on demand. In the brake system, the accumulators provide hydraulic pressure for the service brakes and the parking brake.Piston (3) moves up and down inside the bore of each accumulator. Dry nitrogen gas (4) has a charge of approximately 5520 kPa (800 psi). The accumulator is charged with dry nitrogen gas through charging valve (5) . Oil from the accumulator charging valve enters pressure oil chamber (2). The oil reaches the pressure oil chamber through outlet port (1). The oil forces piston (3) against the dry nitrogen gas charge. The compressed nitrogen gas provides the resistance that maintains the pressure of the oil. When the pressure in the accumulator reaches approximately 14500 kPa (2100 psi), the supply of oil is stopped by the accumulator charging valve. When either the service brakes or the parking brake is applied, oil from pressure oil chamber (2) flows out of pressure port (1) to the brake control valves. When the brakes are applied, the oil pressure in the accumulator is decreased. When the oil pressure in the accumulator decreases to approximately 11700 kPa (1700 psi), the accumulator charging valve will allow pump flow into the accumulator to repeat the cycle.