Uncategorized

The History of Brakes

The History of BrakesThe brake is what makes it possible for humans to control a motor vehicle for a safer riding condition. For over a century, braking systems have evolved into a more complex device to adapt to different road conditions. Many forms of brakes have already existed, and we are going to break down their history.

Wooden block brakes1.  Wooden block brakes

The earliest brake system consisted of nothing more than a simple lever that moved a block of wood against the wheels. This method was effective on steel-rimmed wheels, which was used in horse-drawn and steam-powered vehicles. This brake could put to a stop a vehicle that was running on speeds of 10-20 mph in sparse traffic. But when the Michelin brothers introduced rubber tires by the late 1890s, the steel rimmed wheels became obsolete, as well as the wooden block brakes. It became useless because the wood grounded the rubber down.

Mechanical drum brakes2. Mechanical drum brakes

Considered as the foundation of the modern braking system, the mechanical drum brake was developed in 1902 by Louis Renault, a French manufacturer and a pioneer in the automobile industry. However, the first, or among the first, to think that a cable-wrapped drum anchored to the vehicles’ chassis could be used to stop momentum was Gottlieb Daimler. He created this first concept of the drum brake in 1899.

In 1901, Wilhelm Maybach designed the first Mercedes with a simple, mechanical drum brake, wherein steel cables were wrapped around the drums of the rear wheels and is operated by a hand lever. But it was Louis Renault who was credited with inventing the drum brake that has become the standard for cars.

Drum brakes work as brake shoes generate friction by rubbing against the inner surface of a brake drum attached to a wheel. There are brakes contracting externally, in which the brake band surrounds the drum; and there are also brakes expanding internally, in which the shoes are forced outward against the drum.

There are some huge drawbacks with external brakes, though. Sometimes, when drivers would go upward on hills, the braked would come unwrapped and give way, sending the vehicle rolling backward. Also, because these brakes are exposed to external elements, they would experience wear and tear more often. They don’t last long and required frequent replacement. Manufacturers then focused on creating internal-expanding drum brakes, making brakes last for 1,000 miles or more.

Expanding internal shoe brakes3. Expanding internal shoe brakes

Prior to the invention of the expanding internal shoe brake, all braking systems were installed outside of the vehicle. This placed the shoes inside the drum brake so that dust, water and other elements were kept out, making the braking process remain effective. This was a very important innovation in the history of braking systems.

 Hydraulic brakes4. Hydraulic brakes

In 1918, Malcolm Loughead (who later changed his name to Lockheed in 1926) proposed a concept of a four-wheel brake system using hydraulics. Using cylinders and tubes, Lockheed used fluids to transfer force to the brake shoe when a pedal was pressed. It required much less effort for the driver to apply brakes.

The hydraulic brake system was first fitted into all four wheels of a Model A Duesenberg car in 1921. However, it was beset with fluid leakage problems, but engineers from the Maxwell Motor Corporation produced rubber cup seals to help solve it. In 1923, the improved Lougheed brakes were offered as an optional upgrade on the Maxwell-Chalmers car for $75. This new brake design was also used in Chrysler cars from 1924 to 1962.

Other car manufacturers followed Chrysler since 1924. American Chrysler Six Phaeton B-70 and the British Triumph 13/35 models were the next car models to be equipped with the improved, four-wheel hydraulic brakes. Then by 1931, US manufacturers such as Dodge, Chrysler’s DeSoto, REO, Franklin Graham and Plymouth were producing their cars with hydraulic brakes.

But Ford and General Motors still used mechanical brakes. GM, by the mid-30s, went to Bendix hydraulic brakes and got offered four-wheel drive mechanical braking system. Later on as more manufacturers chose hydraulic over mechanical brakes, Bendix eventually purchased Lockheed’s hydraulic brake company, and so, GM switched to using hydraulic brakes to all of their cars. Meanwhile, Ford was the last manufacturer to adopt hydraulics. They had mechanical brakes applied to a drum inside the transmission and used these until 1938.

Disc brakes5. Disc brakes

The disc brake was invented decades before it became popular. In 1898, Elmer Ambrose Sperry designed an electric car with front-wheel disc brakes built by the Cleveland Machine Screw Co. Disc brakes work like bicycle brakes, wherein a caliper with brake pads pinches a disc or rotor. However, it was William Lanchester, an English engineer, who patented the idea in 1902. The biggest downside to his invention though, was the horrible screeching noise it makes made by copper brake linings moving against a metal disc. After five years, another British named Herbert Frood solved the noise problem by lining the pads with long-lasting asbestos, which continued to be used in car brakes until the 1980s.

Still, the disc brakes were not yet popular. It only began to be widely used in Europe during the 1950s when vehicles’ weight and speed capabilities were increasing, causing hydraulic brakes to become less efficient in distributing heat. The disc brakes were first integrated in Chrysler Imperial since 1949 and 1953, and was first used with hydraulic functions.

In the US, Crosley Motors became the first American manufacturer to fit disc brakes. In 1949, it was fitted to Crosley’s Hotshot model, but discontinued in 1950. These brakes, built by Auto Specialists Manufacturing Company (Ausco), used twin discs that spread apart and rub against the interior of a cast-iron drum. Less pedal pressure than caliper discs were required, and more friction surface than the drum brakes were provided.

In 1962, Bendix impressed the industry when it supplied four-wheel disc brakes as standard fit for the high-performance Studebaker Advant and as optional extras for Hawk and V8 Lark models. It took only a few years for other cars to adopt disc brakes, since the increasing speed and size of cars could no longer match the capabilities of drum brakes.

During the 1960s, many auto manufacturers worldwide started to replace drum brakes with disc brakes. Some of the companies that were the first to do so in their countries were Italy’s Lancia in 1960, Germany’s Mercedes-Benz in 1961, France’s Renault in 1962, Japan’s Nissan in 1965 and Sweden’s Volvo in 1966.

Anti-lock brakes6. Anti-lock brakes

The anti-lock (anti-skid) brake system, or the ABS, was created to help previous braking systems to prevent the brakes from locking up while in use. It’s a safety feature that uses speed sensors that detect when a lock is about to occur. It then ignites a system of hydraulic valves to reduce the pressure of a brake on a single wheel, preventing the car from going into a spin. This system changed the way brakes function and is useful in providing more control for the driver.

Anti-lock brakes were first introduced by French engineer and aeronautical pioneer Gabriel Voisin in 1929 for use in airplanes. It was improved by Bosch and Mercedes-Benz in 1936 by making it an electronic brake system for the Mercedes.

In 1958, the Road Research Laboratory (RRL) and Dunlop developed a practical, mechanical ABS for a car and tested it on Jaguar Mark VII fitted with disc brakes. It was only in 1966 when the ABS was fitted in a production car, the Jensen FF sports sedan, from Great Britain.

Meanwhile in the US, Ford offered an anti-skid system as an option for the 1954 Lincoln Continental Mark II. However, it was very expensive to produce, so it costed too much and was soon withdrawn. In 1968, For introduced the “Sure-Track” analogue anti-lock brake system which operated only on rear wheels. This system used wheel sensors that transmitted data to a transistorized computer set behind the glove box. Production costs was still too high, so it was initially offered as an option for the Thunderbird, until it became a standard fit on the 1970 Mark III.

Bosch and Mercedes updated their 1936 anti-lock brake system and installed it in the 1978 Mercedes S-Class. It was a completely electronic, four-wheel and multi-channel system, which other companies soon built on most cars. In 2006, Mercedes released a further update with the Brake Distronic Plus system, which used long- and short-range radar that can bring a car to a stop even if the driver does not touch the brake pedal to prevent rear-end collisions. Nowadays, most cars – regardless of price class – are fitted with this type of brake system.

Four-wheel brakes7. Four-wheel brakes

As speeds of vehicles increase, manufacturers began to look for improvements in brakes. One of the earliest innovation happened in 1903, when four-wheel brakes were fitted to the Dutch Spyker 60/80 hp model.

Italian automaker Isotta Fraschini Company was also one of the first makers of cars with four-wheel brakes, after their invention of a 15.9 hp car model by Arrol-Johnston of Scotland which used the same brake system. A patent for the brake was granted in 1910 to Giustino Cattaneo of Isotta Fraschini.

Another development arose in the US in 1915 when Duesenberg created cars that applied internal brakes to both front and rear wheels. The cars, which could reach 80 mph on a straightaway, entered in the Elgin Road race. In 1919, a Spanish automobile company Hispano-Suiza used a single foot pedal to operate four-wheel brakes in its H6B model. Before that, it was a common requirement to operate a separate hand and foot brake simultaneously.

At the New York Auto Show in 1923, only Duesenberg and Rickenbacker had cars with four-wheel brakes. The next year, the number of manufacturers participating in the event, who offered four-wheel brakes had increased to 26. By the 1980s, most cars were equipped with four-wheel drive disc brakes

Power-assisted brakes8. Power-assisted brakes

The power brake is a standard feature of most cars nowadays that we don’t even think of its origins. It was actually one of the earliest innovations with brakes – Chicago-based automobile maker Tincher first made brake assist available in 1903. It used a small pump to compress the air and stop the car, and you may also use the same pump to inflate the tires or signal the whistle.

The Pierce-Arrow’s 1928 production car had vacuum-operated power booster for brakes – the Bragg-Kliesrath brakes invented by Bendix’s Victor Kliesrath and racecar driver Caleb Bragg. This vacuum-assisted brake booster was originally intended for aeronautics. The intake manifold supplied the vacuum needed to reduce the amount of effort needed to apply the brakes.

The vacuum booster brake system we know today has its origins in 1927, when a Belgian engineer Albert Dewandre invented the servo-brake or brake booster system he called “Dewandre.” In the same year, Chandler cars came with a Westinghouse Vacuum Booster. By the 1930s, vacuum-assisted drum brakes were fitted into Cadillac, Lincoln, Mercedes, Duesenberg and Stutz cars. But drum brakes remained as the standard that time, because they worked well and were cheaper to produce than disc brakes.

While the vacuum boost power brakes are the most popular type of power-assisted brakes, there were other power brake systems that began to appear. The Hydrovac system started to be available in the 1940s. As the driver applies pressure to the brake pedal, the fluid pressure was increased to a slave cylinder and the wheel cylinders.

Meanwhile, there’s also the Hydroboost system which relied on power-generated steering pump. The Bendix power booster – the Treadle Vac – was mounted on the floorboard right under the brake pedal and was available on all GM cars during the 50s, and also on Lincoln, Mercedes, Hudson, Nash, Mercury and Edsel models. The Treadle-Vac was a single line system, meaning, a failure on any hose or joint could impair the entire system.

Self-adjusting brakes9. Self-adjusting brakes

In 1925, Cole Motor had the earliest (or probably one of the earliest) self-adjusting brakes. They fitted it on the Series 890 Cole, during their last year of production. Around those years, Jowett Cars also installed their self-adjusting brakes to all four wheels of their Sedan, Brougham and Touring models at extra cost.

The self-adjusting brakes did not appear again until 1946, when Studebaker used a Wagner Electric mechanism. In its self-adjusting feature, the linings wore down and the pin and lever moved against a tension spring, which engages the adjusting wedge which moved the linings slightly and kept them at the same distance from the drums. This type of brakes were included in the 1957 Mercury in the 1958 Edsel and in the mid-1960s AMC cars. It was recommended to buyers who want to avoid frequent and expensive brake adjustments.