PISTON 6E5875 - Caterpillar

Illustration 1 g00363478
The Service Brake Control for the All Wheel Steer (1) Brake pedal. (2) Plate. (3) Rollers. (4) Pistons.The brake control valve consists of two identical valves. The valves are mounted in the same casting. Two rollers (3) are connected to the brake pedal (1). The rollers (3) contact the plate (2). The plate (2) is attached to both pistons (4). When the operator depresses the brake pedal (1), both pistons (4) move at the same time.There are two modes of operation for the service brake control valve. The two modes are power mode and manual mode. In the power mode, the valve operates as a pressure reducing valve. The force of the brake pedal causes a specific pressure at the service brakes. In the manual mode, the valve operates as a two-stage pump. The manual mode occurs when the pressure at the inlet port (7) is within 0 to 415 kPa (0 to 60 psi) or below the pressure at the load sensing port (6).
Illustration 2 g00362373
Top View of the Service Brake Control Valve (4) Pistons. (5) Crosshole for equalization. (6) Load sensing port. (7) Inlet port. (8) Tank port. (9) Orifice. (10) Outlet port to the brake piston.
Illustration 3 g00360478
View A-A (4) Piston. (6) Load sensing port. (7) Inlet port. (8) Tank port. (11) Shutoff valve. (12) Check valve. (13) Orifice.
Illustration 4 g00362358
(4) Piston. (6) Load sensing port. (7) Inlet port. (8) Tank port. (14) Spool chamber. (15) Piston chamber. (16) Spring. (17) Spool. (18) Metering notches. (19) Makeup check valve. (20) Pin. (21) Relief valve.In the power mode, the valve is supplied with pressurized hydraulic oil at the inlet port (7). When the operator depresses the brake pedal (1), the brake pedal (1) moves the piston (4). The piston