Kubota WSM STa-30, Workshop Manual

Page: 203 / 359

5-M1
ST
α
-30 · ST
α
-35, WSM BRAKES
1. FEATURES
W1013188
Independent mechanical wet disc brakes are used for the right and left travelling brakes. They are operated by the
brake pedals through the mechanical linkages and provide stable braking and require little adjustment.
The parking brake is mechanical type which is connected to the brake lever by the rod linkages.
■
Features of Wet Disc Brakes
1. Reduced disc wear
Although wet discs are worn by approx. several tens of microns depending on the accuracy of parts during the initial
contact in initial period of 50 hours or so, almost no wear occurs afterward. This means that very little brake
adjustments are required.
2. Stable braking
Since the brake discs are immersed in transmission oil, Fade* is rarely caused even after repeated braking and a
stable braking force is obtained.
3. Pedal stroke does not change under influence of heat
Unlike internal expanding type brakes, the drum-to-shoe clearance of the wet disc brake does not increase due to
thermal expansion and the increased pedal stroke does not result. Thus, the wet disc brake provides a constant pedal
stroke.
* Fade
Fade is a phenomenon of braking force loss caused
by the heat generated in repeated braking. Generally,
the friction coefficient of brake disc tends to lower and the
braking force reduces with the rise of the temperature of
the brake disc.
(Reference)
• Relationship between temperature and friction
coefficient of brake disc.
W1012831
(1) Rear Axle Case
(2) Parkiing Brake Rod Linkage
(3) Parking Brake Lever
(4) Brake Rod
(5) Brake Pedal
(6) Brake Cam Lever
A : Friction Coefficient (
μ
) B : Temperature
KiSC issued 11, 2006 A