TUBE 0011534 - Caterpillar

Illustration 1 g00518187
Hydraulic control mechanism (27) Stop (28) Plunger (29) Spring (30) Spring (31) Chamber (32) Valve (33) Passage (34) Passage (35) Piston (36) Chamber (37) Chamber (38) Passage (39) Passage (40) Plunger (41) Passage (42) LeverPressure oil flows to the hydraulic control mechanisms. The oil flows from the manifold on the steering control valve. The oil flows into the housing of the hydraulic control mechanism and the oil fills chamber (31) .When the brakes are in the OFF position, the oil is held in chamber (31) .When the brake pedal is pushed forward, lever (42) pushes plunger (28) and valve (32) to the right against piston (35). This movement closes passage (33) in the piston. The movement of plunger (28) and valve (32) opens passages (38), (39) and (41). The oil from chamber (31) flows through passage (41) and the oil moves plunger (40). The oil flows through plunger (28) to the center of valve (32). The oil flows through holes in valve (32) and out passage (38). The oil flows through passages (38) and (39) and the oil starts to fill the chamber. When the pressure in chamber (37) increases, piston (35) moves to the right. The piston contacts the bellcrank of the brake linkage. The bellcrank moves the mechanical linkage and the brake band contacts the steering clutch drum.When the brake pedal is released, lever (42) moves against stop (27). The force of springs (29) and (30) moves plunger (28) and valve (32) away from piston (35). The movement of valve (32) and plunger (28) closes passages (38), (39) and (41). The movement opens passage (33). The pressure in chamber (37) decreases. Piston (35) moves away from