Braking System Operation Flashcards
True or False:
Braking force is 50% in the front and 50% in the rear?
False
Front brakes can apply 60-80% of the braking power depending on the weight distribution (front or rear drive)
What is a brake master cylinder?
The master cylinder converts force into hydraulic pressure. Pressure from the brake pedal forces hydraulic fluid through brake lines to push the pistons.
Review Master Cylinder diagram on LH, “Braking System Operation” page 3
: )
What are the two types of caliper brake designs? (describe)
Fixed: Pistons on BOTH SIDES of the brake caliper (can have 2, 4, 6 or 8 pistons)
Floating: Uses only 1 or 2 pistons on ONE SIDE, caliper body slides in reaction to piston movement.
What are the two types of drum brake designs? (describe)
Dual Servo:
Two brake shoes connected by a link or an adjuster. The front (primary) shoe moves first and transfers force to the rear (secondary) shoe, increasing braking force.
Non-Servo:
One shoe (leading) moves in the direction of the drum rotation, while the other (trailing) moves opposite.
What does ABS stand for?
Anti-Lock Brake System
What does ABS do?
ABS prevents wheel lock-up to reduce stopping distance & help maintain steering control
-by preventing wheel lock-up, tires will maintain traction with road surface
True or False: ABS is only for commuter vehicles
False: ABS is used on Motorcycles, and even trucks & buses with air brakes.
What is a wheel speed sensor?
A magnetic impulse sensor that creates an AC voltage signal as the tone ring rotates the wheel.
What allows the piston to retract in place of a return spring?
The calipers square cut rubber seal flexes when the brakes are applied. The seal relaxes as the piston is released.
In a dual servo brake system, which brake shoe is longer?
The secondary shoe (rear)
In a dual servo brake system, the secondary (rear) shoe provides what percentage of the application force?
~70%
What type of vehicles commonly use dual servo brakes?
Mainly Rear-Wheel Drive
In a non-servo brake system, do the brake shoes rest on a fixed anchor?
Yes.
The shoes are affixed to solid anchor at the bottom of the assembly where the shoes pivot from.
In a non-servo brake system, which brake shoe does more work?
The leading (front) shoe
True or False: In a non-servo brake system, drum rotation does not increase braking force.
False
True or False: Non-Servo Brake shoes are equal length
True
Define servo-action
One shoe “serves” the other to increase application force
* front (primary) shoe helps increase pressure on rear (secondary) shoe
this is referred to as servo action
True or False: Dual Servo Brakes can rotate with the drum
Yes, they can
What type of vehicles commonly use non-servo brakes?
Front wheel drive
Review non-servo and dual servo braking diagrams
LH -> midterm
Dual servo: page 9
Non-servo: page 11
