TUBE AS 3464439 - Caterpillar

Air Circuit For The Wheel Brakes
The air circuit for the wheel brakes provides air to activate the hydraulic circuit for the wheel brakes. The components of the air circuit for the wheel brakes are: brake control valve (15), air pressure switch (10) for wheel brakes and air/hydraulic cylinders (14).Air pressure switch (10) located at the top of the air reservoir activates a warning light on the dashboard when air pressure in the system is too low.
Cab
(15) Brake control valve.Air from the reservoir goes to brake control valve (15). Brake control valve (15) is located below the brake pedal. The brake control valve sends air pressure to the air/hydraulic cylinders to activate the wheel brakes when the brake pedal is depressed. The pressure of the air from the valve increases the farther the pedal is pushed down. As the air pressure increases, there is also an increase in the braking force.Hydraulic Circuit For The Wheel Brakes
The hydraulic circuit for the wheel brakes engages the wheel brakes when the air circuit causes brake fluid pressure in the hydraulic circuit. The components of the hydraulic circuit are: master cylinder [part of air/hydraulic cylinder (14) and two wheel brakes (13).Air/hydraulic cylinder (14) has two pistons, one for the air cylinder and one for the brake fluid master cylinder. Movement of the air cylinder piston is caused by air pressure. This movement also causes the master cylinder piston to move. This causes the wheel brake caliper pistons to move the brake linings against the disc. The wheel brakes are now applied. The master cylinder is part of the hydraulic circuit for the wheel brakes.
Air/hydraulic Cylinder Location
(14) Air/hydraulic cylinder. (22) Brake pressure switch. (23) Brake fluid reservoir.The brake fluid master cylinder has fluid reservoir (23), to hold extra brake fluid for the brake hydraulic system. Brake pressure switch (22) is closed by pressure in the brake hydraulic circuit and is used to turn on the brake lights at the rear of the machine.Transmission Control Circuit
The transmission control circuit consists of speed control valve (5), speed shift cylinder (2), direction control valve (6) and direction shift cylinder (3).
Operator Console
(5) Speed control valve.
Operator Console
(6) Direction control valve.
Left Side Of Transmission
(2) Transmission speed shift cylinder. (3) Transmission direction shift cylinder.Direction shift cylinder (3) is connected to the direction control valve spool in the transmission control group. The control valve spool has three positions: forward, neutral and reverse. The cylinder is returned to the center or neutral position by a spring.Speed shift cylinder (2) is connected to the speed control valve spool in the transmission control group. The speed control valve spool has three positions: first speed, second speed and third speed. The cylinder is returned to the center or second speed position by a spring.Operation
Speed control valve (5) is a three position valve.