Air Brakes Flashcards
What is a foot valve responsible for (3 things) as well as list its other name?
The treadle Valve:
- Foot pedal Feel
- Actuating pressure to relay circuit
- Acts as the relay piston
Another name for a two way check valve
A shuttle valve
What circuit locks out the inversion valve?
The primary Circuit
Two types of automatic slack adjusters
Clearance, Stroke
what are rotochambers used for?
Off road applications
what are two purposed of a slack adjuster?
To spline to s-cam or wedge to adjust slack,
To act as a lever
What is a trailer application valve?
(Known as broker break/ spike) actuates and engages the trailers breaks.
What is a relay valve?
Remote control valve (uses 25 psi to trigger use) used to reduce break application and release times (crack pressure change).
Crack pressure
The required pressure to actuate so it can start to meter air.
Quick release valves
Help speed the exhausting of air from a circuit, tends to have one inlet and two outlets.
Basically used to just release excess air in a circuit instead of having it go back to the source valve.
Ratio Valve
Limits front axle breaking under light and medium applications.
The valve wont crack unless it goes over 10, 10-40 psi is 50% APPLIED, while 60 psi is 100% Applied
Inversion Valves
Improves breaking under emergency conditions,
Informs the foot valve (treadle) to send a signal to ease off the air in the spring breaks to help effect and emergency stop.
Bobtail proportioning valve
Designed to help reduce normal break service application pressure anytime the tractor isn’t connected to a trailer. (During bob tailing mode the front brakes receive full breaking pressure).
Tractor Protection valves
First: acts as a means of routing and switching the trailer air supply and trailer service from the tractor.
Second: Protects tractor air supply in the event of a trailer breakaway or total air loss
What are stop lamp switches?
it is used to illuminate the brake lights on the vehicle. rated by how much air pressure it takes to close the circuit.
Brake chamber are?
They are used to convert air pressure into mechanical force to stop a vehicle
Components: Diaphragm, Retraction spring, and pushrod
What are long stroke chambers?
used to produce longer strokes by increasing the distance between the pressure and non pressure plates of the chamber.
Name all six brake imbalance terms?
- Brake torque imbalance,
- Jackknife,
- trailer swing,
- plow-out,
- pneumatic timing,
- Pneumatic balance
Split-Coefficient stops
helps balance vehicle if the vehicles one side is on ice while the other is on pavement
Helps maintaining maximum road traction
What is the difference between park on air and park on spring trailer brakes?
Park on air: Brake chambers charged with air
Park On spring: Brake chamber mechanically actuated (springs on)
What are the shapes and colours of the System Park Valve, Trailer supply valve and tractor park valve?
- System Park valve: Diamond and Yellow shaped ) (When pulled out bother other brakes are pulled out as well and placed into park)
- Trailer supply valve: Octagonal and red (when pushed in 60 psi is used to hold off spring brakes)
- Tractor Park Valve: Round an blue
Two devices used on foundation brakes:
S-cam and wedge
What is DD3 chambers used for?
In transit and intercity buses
Where are the LED’s located on a bendix ABS modulator controller assembly?
On the Controller assembly
