Some trucks have disc brakes instead of S-Cam brakes. Air pressure works on the brake chamber and the slack adjuster in the same way that it does in S-Cam brakes. However, a power screw replaces the S-Cam. The power screw is turned by the pressure on the brake chamber and the slack adjuster. Then the power screw grasps the disc or rotor between a caliper's brake lining pads.
The many benefits of air disc brakes include the following:
Compared to drum brakes, air disc brakes reduce stopping distances by almost 40 percent. Because pressure is continually applied, it's easier for the vehicle to come to a complete stop.
Air disc brakes almost completely stop brake fade.Air disc brakes don't increase the wear of brake linings on a trailer or disc pads on a tractor.
Still, despite all of the advantages, change isn't always embraced by the masses. In the United States, no regulation demands the use of air disc brakes, which are viewed as a high-end item because they're about twice the cost of drum brakes. Currently, about 95 percent of the U.S. heavy-duty truck market relies on drum brakes. In Europe, more than 80 percent of commercial trucks already use air disc brakes. The complete shift to air disc brakes may require 10 to 15 years.
They say that a picture is worth a thousand words.
Truck Brake Diagram
Now let's put the parts together to see how truck brakes work as a whole. This diagram provides both a closeup view and an example of where the brakes are located in your vehicle.
Truck Brake Types
Service brakes are used during normal driving. A sequence of events occurs when a driver pushes the brake pedal.
Air moves into a brake chamber through airlines.
The air forces out a pushrod.
The pushrod pushes the slack adjuster.
The camshaft turns.
The turning of the camshaft twists the S-Cam. (You guessed it -- it's called an S-Cam because it's in the shape of an S.)
The brake linings are forced to contact the brake drum.
The driver activates the parking brakes by pulling out one or both of the valves on the dash. (Tractor brakes have a yellow button; trailer brakes have a red button.) The dash button releases the spring inside the brake chamber, thus beginning steps 3-6 listed above.
The emergency brake system uses parts of the other two systems to stop the truck if brake failure takes place
Inside the brake chamber is a powerful spring with about 2,500 pounds of pressure behind it. That spring is held back by a steady and constant airflow in the chamber. The emergency brakes deploy automatically if there's not enough air in the system to hold the spring back. If air pressure drops below 60 pounds per square inch, the low-pressure light comes on. A buzzer may also sound.
Not everyone is happy with the way that S-Cam brakes work. A recent innovation is the use of disc brakes. Let's head down the highway to see how disc brakes work on trucks.
Big Disc Brakes for Trucks
Source
İnternational Sales and Customer Relations
Mob=+ 90 530 320 60 22
E-Mail : export@continual.com.tr
Continual Brake Caliper Systems
www.continual.com.tr
HMF Plastik. Tesktil. İnş. Gıda San. Tic. Ltd. Şti.
Phone :+90-212 671 68 23
Fax :+90-212 671 68 30
skype: continualsales
Showroom Address =
İkitelli Organize Sanayi Bölgesi Dolapdere Sanayi Sitesi 2.ada No: 2 İKİTELLİ-BAŞAKŞEHİR / İSTANBUL / TURKEY
Factory Address =
Fevzi Çakmak Mahallesi Büsan Ozel Organize Sanayi Sitesi 10664 Sokak No:31/D Karatay/KONYA/TURKEY
İnternational Sales and Customer Relations
Mob=+ 90 530 320 60 22
E-Mail : export@continual.com.tr
Continual Brake Caliper Systems
www.continual.com.tr
HMF Plastik. Tesktil. İnş. Gıda San. Tic. Ltd. Şti.
Phone :+90-212 671 68 23
Fax :+90-212 671 68 30
skype: continualsales
Showroom Address =
İkitelli Organize Sanayi Bölgesi Dolapdere Sanayi Sitesi 2.ada No: 2 İKİTELLİ-BAŞAKŞEHİR / İSTANBUL / TURKEY
Factory Address =
Fevzi Çakmak Mahallesi Büsan Ozel Organize Sanayi Sitesi 10664 Sokak No:31/D Karatay/KONYA/TURKEY
