What is the purpose of dual brake valve?
The Bendix® E-7™ dual brake valve is a suspended, pedal-operated type brake valve with two separate supply and delivery circuits for service and emergency braking, which provides the driver with a graduated control for apply- ing and releasing the vehicle brakes.
What is a dual foot valve?
Dual circuit brake valves utilize two separate supply and delivery circuits for service and secondary braking. The number one or primary circuit portion is mechanically operated through the action of the treadle/pedal and plunger.
What is a brake foot valve?
The foot brake valve is used to actuate and control the brakes on all wheels when the vehicle is in motion. The common reference is to the service brake control valve.
How does a brake valve work?
It is a spring-loaded component that activates when fluid pressure builds when you step on the brake pedal. Then, the valve’s plunger unseats and fluid rushes into the calibrated range. Once this happens, the spring gets compressed and the plunger blocks the fluid from passing through.
What is a dual circuit air brake system?
A dual air brake system has two separate air brake systems, which use a single set of brake controls. Each system has its own air tanks, hoses, lines, etc. One system typically operates the regular brakes on the rear axle or axles.
How do brake chambers work?
A service brake chamber contains a flexible rubber disc called a diaphragm, a metal rod called a pushrod and a return spring. When you press the brake pedal, compressed air fills the service brake chamber, causing the diaphragm to move and push out the pushrod to apply the brakes (Diagram 3-1).
How does a brake combination valve work?
It senses pressure going to the front brakes only. When you press the pedal and pressure rises, the switch is forced closed. This completes the electrical circuit and turns on the Brake Lights. This type of combination valve eliminates the need for a brake light switch on the pedal assembly.
How does a dual brake master cylinder work?
In essence, a master cylinder is a pump, and operation of the dual master cylinder is simple. When the brake pedal is depressed, force is applied through the push-rod to the master cylinder piston. The piston actually has two seals, and pushes in two chambers of the master cylinder, with a line to each circuit.
How does the dual braking system provides an important safety feature?
The concept of the dual-circuit brake system is to eliminate a total brake failure if there is a fault with any part of vehicle’s brake components. This will allow the driver to bring a heavy vehicle to a safe stop even if part of the braking system has a problem.
How are dual braking systems split?
For safety reasons, the hydraulic brake system is divided into two independent brake circuits. Two diagonally opposite wheels form one brake circuit. This means that each brake circuit acts on one front wheel and the diagonally opposite rear wheel. If one of the circuits fails, the second ensures residual braking.
What is function of proportioning valve in hydraulic braking system?
In cars with disc brakes on the front and drum brakes on the back, more pressure is needed for the disc brakes in the front. The proportioning valve prevents the rear brakes from engaging before the front brakes during panic stops.