HOUSING 3T3066 - Caterpillar

Illustration 1 g00822287
Location of Brake Components (1) Lever (2) Brake cylinder (3) Brake discs (4) Flange (5) Annular chamber (6) Piston spring (7) Piston (8) Center housing (9) Screw (10) Shaft (11) Pressure plate (12) Pressure plates (13) Hub (14) Axle shaft (15) Cam (16) Axle housingBrake packs are installed in brake cylinders (2). The brake cylinders are located between center housing (8) and axle housings (16) on the right side and on the left side of the front axle differential. There are three brake discs (3), four thin pressure plates (11) and one thick pressure plate (12) in each brake pack.Grooves on each side of brake discs (3) allow the oil from the differential to flow through the brake disc packs for cooling purposes. Pressure plates (11) and (12) are smooth on both sides. Teeth around the outer circumference of pressure plates (11) and (12) are located in teeth around the inner circumference of brake cylinder (2) in order to prevent the pressure plates from rotating. Splines on the inside diameter of brake disc (3) are located in splines on the outside diameter of hub (13). The hub is splined onto axle shaft (14) in order to allow the hub and the brake discs to rotate with the axle shaft.When pressure is applied to the service brake pedal, hydraulic pressure builds up in annular chamber (5). The pressure of the oil pushes piston (7) against pressure plate (11). Brake discs (3) and pressure plates (12) are squeezed together and the axle shaft is prevented from rotating. When pressure on the service brake pedal is released, the springs in automatic brake adjuster (6) move piston (7) away from pressure plate (11). The pressure plates and the brake discs separate, and the axle shaft is free to rotate.Piston (7) includes automatic brake adjusters (6). The adjusters move the piston closer to the brake pack in order to compensate for wear in the brake discs. This ensures that the movement of the brake pedal will remain constant during the life of the discs.Lever (1) is connected by a cable to the parking brake pedal. The lever is splined to shaft (10). One end of the shaft is located in the bottom of brake cylinder (2), and the other end of the shaft is supported by flange (4) at the top of the brake cylinder. Cam (15) is splined to shaft (10). The cam rotates with shaft (10) when the parking brake pedal is applied. The cam forces pressure plate (11) against the brake pack. Brake discs (3) and pressure plates (12) are forced into contact and the axle shaft is prevented from rotating.