Braking Systems : Past, Present & Future
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Braking Systems : Past, Present & Future Akshat Sharma*,Amit Kumar Marwah** *Student, Department of Mechanical Engineering, MIT Ujjain(M.P.) **Associate professor, Department of Mechanical Engineering, MIT, Ujjain (M.P.) Email: [email protected] A major test of brake systems took place in 1902 on an Abstract:- Humans have always been fascinated by the unpaved road in New York City called Riverside Drive. idea of going faster than before . With advancements in the Ransom E. Olds had arranged to test a new brake system IC engine technologies and then Jet Propulsion Engine the against the tire brake of a four-horse coach and the internal highest speed that vehicles can reach has multiplied drum brake of a Victoria horseless carriage. His manifold. However as the speeds of vehicles go up the Oldsmobile sported a single flexible stainless-steel band, technology required to safely stop these vehicles must wrapped around a drum on the rear axle. When the brake evolve. Braking systems have had tremendous pedal was applied, the band contracted to grip the drum. A transformations from lever type brakes on horse carriages vast improvement on brakes was born, one that would pave to multi layered carbon ceramic disc type brakes to air the way for the systems afterwards. The repercussions of brakes used on land speed record braking cars. While the which spread to every facet of the industry, even something technology used to power vehicles to higher than ever like being able to compare car insurance without the speeds is what catches popular imagination the same has advancements in brakes that have taken place. Olds had not been the case with evolution of braking systems. entered his car in the Blue Ribbon Contest, a 100-mile race This paper aims to sketch a history of braking systems scheduled for August and wanted to be sure his external brake over the years and make a study of the present and future was a match for the Victoria's expanding-shoe internal drum of the same design and the coach's tire brake -- a pad that was applied to the tire by a long lever. Keywords:- Braking systems, history of braking systems Although it ground down solid rubber tires pretty quickly, the I. INTRODUCTION tire brake was popular on carriages and many early autos. As vehicles have developed over the years the technology From a thunderous speed of 14 mph, the Oldsmobile stopped required to stop these vehicles has also undergone a massive in 21.5 ft., the Victoria in 37 ft. and the horses (which may not evolution. The first type of brakes were external type brakes have been going 14 mph, but had no engine braking to aid used on horse carriages which were actuated by means of a them) in 77.5 ft. The Oldsmobile went on to win two of nine lever which brought a rubber pads in contact to axle . These blue ribbons awarded in the race. The car's braking system were followed by internal brakes using drums or disks made such a big impression on other manufacturers that by attached to each wheel. This paper sketches a history of these 1903 most had adopted it. By 1904, practically all car makers braking systems. It also discusses about the present trends and were building cars with an external brake on each rear wheel. future prospects in the world of brakes. Almost at once, the external brake demonstrated some serious flaws in everyday use. On hills, for example, the brake unwrapped and gave way after several seconds. A driver II. HISTORY OF BRAKING SYSTEMS unlucky enough to stall on a grade soon found himself rolling backward. For this reason, chocks were an important piece of was interrupted. Meanwhile in Great Britain, a patent was on-board equipment. It was a common sight to see a passenger issued in 1902 to F. W. Lanchester for a nonelectric spot disc scurrying from inside the car with wood in his hands to block braking system that's similar in principle to what we have the wheels. There was another drawback to the external brake. today. The biggest problem that Lanchester encountered was It had no protection from dirt so its bands and drums quickly noise. Metal-to-metal contact between his copper linings and wore. A brake job every 200 to 300 miles was considered the metal disc caused an intense screech that sent chills normal. through anyone within earshot. The problem was solved in 1907 when Herbert Frood, another Englishman, came up with The problems associated with the external brake were the idea of lining pads with asbestos. The new material was overcome by the internal brake. As long as the brake shoes quickly adopted by car manufacturers on both drum and disc were under pressure, they stayed against the drums to keep the brakes. Asbestos linings also outlasted other friction materials car from rolling backward on hills. And, since brake parts by a wide margin. The 10,000-mile brake job had arrived. As were inside drums and protected from dirt, drivers could go roads improved and cars began to be driven at high speeds, over 1,000 miles between brake overhauls. The drum brake, as manufacturers recognized the need for even greater braking it is now known, became all-dominant in the United States. In power. Europe, particularly in Great Britain, it had to share the stage with disc brakes. Disc brakes became more or less standard on One solution to the problem became apparent during the Elgin European cars during the '50s, about 20 years before they were road Race of 1915. A Duesenberg took the flats at 80 mph, adopted by American manufacturers in 1973. This is ironic, then screeched to a virtual crawl to negotiate the hairpin because the spot-type disc brake is an American invention. In curves. Duesenberg's secret for such magnificent braking 1898, Elmer Ambrose Sperry of Cleveland designed an power was to simply use an internal brake on each front wheel electric car having front-wheel disc brakes. as well as each rear wheel. In 1918, a young inventor named Malcolm Lougheed (who later changed the spelling of his name to Lockheed) applied hydraulics to braking. He used cylinders and tubes to transmit fluid pressure against brake shoes, pushing the shoes against the drums. In 1921, the first passenger car to be equipped with four-wheel hydraulic brakes appeared -- the Model A Duesenberg. Carmakers as a group were not quick to adopt hydraulics. Ten years after the Model A Duesie, in 1931, only Chrysler, Dodge, Desoto, Plymouth, Auburn, Franklin, Reo, and Graham had hydraulic brakes. All the others still had cable-operated mechanical brakes. In fact, it was not until 1939 that Ford finally gave in, becoming the last major manufacturer to switch to hydraulic brakes. Fig. 1. An Oldsmobile horse carriage using lever type The basic braking system we have today was pretty much in external brakes[1] place by 1921, including a refinement some regard as contemporary -- power assist. Power assist, technically, dates He made a large disc integral with the hub on each wheel. back to 1903 when a car called the Tincher used air brakes. Electromagnets were used to press smaller discs, lined with a But the first car to be equipped with a vacuum-operated power friction material, against spots on the rotating disc to bring the booster similar to those we have today was the 1928 Pierce- wheel to a stop. Springs retracted the spot discs when current Arrow. It used vacuum from the inlet manifold to reduce the two , they tend to wear more and have a high cost of physical effort needed to apply brakes. Vacuum boosters from maintenance . thus they have a lower economic as well as then to now have similar designs. The first widespread overall efficiency. Disc brakes on the other hand have become deviation from vacuum power assist came about in 1985. synonyms for exceptional braking power , vehicles with disc Some '85 GM cars use an electrically driven brake booster, brakes are considered high end since they are costlier and are which is smaller and lighter than the conventional vacuum much more effective than drum brakes the mechanism used booster, giving an all-hydraulic system. Some cars with for driving the disc or drum brakes is what mainly antilock brakes also use all-hydraulic systems. differentiates the vehicles today. Let us first discuss the drum and disc brakes in detail first :- The first car to have self-adjusting brakes was the 1925 Cole. The prototype for today's systems appeared on the 1946 1). Drum Brakes:- Studebaker. The mechanism by Wagner Electric Co., A drum brake is a brake that uses friction caused by a set consisted of an adjusting wedge under the influence of a of shoes or pads that press against a rotating drum-shaped part tension spring. As linings wore, a plug receded to move a pin called a brake drum. The term drum brake usually means a and lever against the spring. This forced the adjusting wedge brake in which shoes press on the inner surface of the drum. against brake shoes, which expanded to keep linings at a When shoes press on the outside of the drum, it is usually preset distance from the drums. As for the antilock (antiskid) called a clasp brake. Where the drum is pinched between two units now available in the U.S., they are hardly new. The first shoes, similar to a conventional disc brake, it is sometimes practical antiskid braking system, named Maxaret, was called a pinch drum brake, though such brakes are relatively developed in 1958 by the Road Research Laboratories in Great rare.