Knuckle (Front Brake) - Kubota RTV1140CPX Workshop Manual

RTV1140CPX, WSM

2. KNUCKLE (FRONT BRAKE)

 Automatic Brake Adjustment
With a mechanical brake system, when the brake pedal is released, seal returns to its original position by spring
tension and cam mechanism.
With a hydraulic brake system, the seal (3) serves to return the brake piston (2) to the original position (no braking
force).
When the brake pedal is pressed, pressure in the knuckle case rises and the brake piston moves in the direction
of arrow and causing the brake discs to press against the knuckle case. At this time, the brake seals are deformed in
the knuckle case (1), and are subjected to elastic deformation as shown in the figure above.
When the brake pedal is released, pressure in the knuckle case reduces due to the brake seals reverting back to
its original form. Together, a clearance is formed between the brake disc and brake piston to prevent the brake
dragging.
Worn brake discs require longer brake piston movement. When the brake piston movement exceeds the elastic
limit of brake seal, sliding occurs between the seals and the brake piston. With the brake seals deformed a clearance
is automatically kept constant.
Basically, the brake body is similar to that of the
mechanical wet disc brake. It is designed to brake when
the brake disc (10) rotating together with the front axle
(1) is pressed.
The knuckle (4) of the hydraulic brake serves as a
master cylinder.
When brake oil pressure increases, the brake piston
(5) is forced out and presses the brake discs against the
knuckle cover (2), thereby causing braking. This brake
uses three brake discs to obtain big braking force.
(1) Front Axle
(2) Knuckle Cover
(3) Plate
(4) Knuckle
(5) Brake Piston
(6) Brake Seal 3
4-M2
BRAKES
(7) Brake Seal 4
(8) Brake Seal 2
(9) Brake Seal 1
(10) Brake Disc
(11) Constant Velocity (CV) Joint
9Y1210293BRM0002US0
(1) Knuckle Case
(2) Brake Piston
(3) Brake Seal
(4) Piston Return Stroke
(A) When brake pedal is
pressed
(B) When brake pedal is
released
9Y1210293BRM0003US0
KiSC issued 05, 2014 A