A Brief History of Air Brakes in Our World
Depending on hydraulic fluid to operate, a braking system can be dangerous. A simple leak could lead to the death of many people. That’s one reason why trains, buses and tractor-trailers rely on air brakes to stop their vehicles. Air brakes have proven themselves an effective and safe braking system.
Before Air Brakes
To stop a train before air brakes were developed, an engineer blew a signal with the train whistle. This alerted the train’s brakemen to apply a hand brake in each rail car. The brakeman would set the brake in one car and then have to jump to the next car and set that brake. Not only was it an inefficient way to stop a train, it was dangerous for the brakemen, who could fall between the rail cars and be injured or killed.
George Westinghouse started a new business in 1869 that made the first triple-valve air-brake system. The new system worked in three steps to efficiently and safely stop a locomotive. 1) The system charged so the brakes could be released. 2) When the brakes were applied, the air pressure decreased and the valve allowed air into the reservoir tanks. 3) The air escaped once the brakes were applied and the increased pressure released the brakes. By working in this manner, even if the brake system failed (lost air) the brakes would be applied and the train would stop. This is the opposite of how other braking systems work: the brakes fail and the vehicle can’t stop. And so began a history of air brakes.
While air brakes were a vast improvement over hand brakes, it could still take time for the air to be pumped throughout the train so the brakes would work. So the first major improvement to the braking system was to add a compressor to the train that pumped air through a brake pipe into an air cylinder in each car.
Automobiles began using air brakes as early as 1903. The first car to have them was called a Tincher. As improvements continued to be made to car air brakes, a vacuum power booster braking system was developed that is similar to modern air brakes. It used a vacuum to reduce the physical strength need to apply the brakes. This system was first used on the 1928 Pierce-Arrow.
Besides Westinghouse, other companies began to develop air brake systems. One of these, Bendix, eventually merged with Westinghouse Automotive Air Brake Company in 1930. By 1934, the company had taken the air braking system worldwide and opened plants in France, Germany, Italy and England.
The outbreak of World War II accelerated improvements and refinements of the air braking system. By 1949, air brakes were standard on heavy trucks, tractor-trailers and buses. Other companies also continued to enter into the market and not only develop air brakes, but newer versions of braking systems.
Air Brakes Today
While a history of Air brakes started in trains and then to cars the most common place we see them now is in heavy trucks, tractor trailers and busses. That being said we are now seeing them return full circle to pick up trucks and recreational vehicles. The environmentally friendly and more powerful braking using air makes them a environmentally friendly choice for vehicles.
So there’s a history of air brakes, for training on how these systems work and about getting an endorsement on your license – give us a call