BASE 4J1905 - Caterpillar

Illustration 1 g00879867
Suspension cylinder (1) Port (accumulator) (2) Piston rod (3) Holes (4) Piston (5) Spring (6) Holes (7) Sleeve (8) Stem (9) Check ball (10) Seat (11) HoleWhen the suspension cylinder is extending, oil from the accumulator flows into piston rod (2) through port (1). This oil flows through hole (11) to the piston side of the suspension cylinder. Check ball (9) is forced onto seat (10). Oil is displaced from the rod side of the suspension cylinder and flows into the piston rod through hole (3) at a controlled rate. This gives the cylinder an amount of damping when the cylinder is extending.When the suspension cylinder is retracting, oil passes from the piston side through hole (11) into the piston rod. Some of this oil flows through holes (3), and past check ball (9) to the rod side. This prevents voiding. The remainder of the oil flows through port (1) to the accumulator.As piston (4) approaches the fully retracted position, hole (11) is closed by stem (8) and sleeve (7). The flow of oil from the piston side to the piston rod is restricted by holes (6). When the piston contacts sleeve (7), the sleeve moves along stem (8). This progressively covers holes (6). This cushions the piston rod increasingly as the piston rod reaches the fully retracted position.