Brake Systems Flashcards
Which 3 factors define braking?
- The amount of pressure applied to the 2 surfaces
- The amount of surface area that is in contact with each other
- The type of material that is used to cause friction between the surfaces
How do drum brakes function?
When the brake pedal is applied, hydraulic pressure presses the brake shoes or shoe pad against the drum, slowing down the wheels
How to disc brakes function?
When the brake pedal is applied, the hydraulic pressure pushes the pistons in the calliper outwards, which squeeze the pads against the rotor to stop wheel motion
Compare and contrast drum and disc brakes
Disc brakes generally have a better performance and heat dissipation which helps prevent brake fade
Drum brakes are cheaper to manufacture and maintain due to simpler design
What is the ABS system?
A safety feature in a car which prevents wheel from locking up during braking
How does the ABS system work?
- Sensors on all wheels monitor wheel speed
- ABS automatically applies and releases brakes on the wheel to prevent lockup
- The pumping action allows wheels to maintain traction with the road surface
How is pressure regulated in the ABS System?
- Speed sensors: monitors the speed of the wheel by sensors that generates a signal
- Valve: each brake has a valve controlled by the ABS, valves are used to apply and cut pressure to the brakes
- Pump: used to restore pressure to brakes when valves released it. Controller detects wheel slip and release the valve taking the pressure off the brake
- ECU: senses wheel traction and limits the brakes by actuating the brake valve
What is regenerative braking?
- A system where kinetic energy stored during deceleration is transferred into another energy store for other uses
- When the brakes are applied, the motor acts as a generator. Kinetic energy is transferred to electrical energy to recharge the battery
