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Car brakes are based on the conversion of kinetic (motion) energy into other forms of energy, usually heat.
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Other, more recent methods include converting the kinetic energy into electrical and potential energy. See Part 2, Section 6.1.7 (Brakes) for further information.
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There are reports of one early car braking system dropping a spike to dig into to the road when a lever was operated.
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Prior to the introduction of pneumatic rubber tires in 1895 the rims of car wheels were initially made of iron and, from the mid 1800s, either steel rimmed or lined with solid rubber.
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The first solid rubber tires were manufactured in 1846 and were initially fitted to carriages and steam powered vehicles.
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On iron or steel rimmed vehicles the driver typically pulled a lever to apply a block of wood to the wheel’s rim. What material was the brake block made of when solid rubber tires were first used? Steel?
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This type of brake is called a “Shoe Brake”. It was reasonably effective up to 10-20 mph.
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The 1885 Benz Patent-Motorwagen (featured on this site’s home page) was fitted with solid rubber tires. The upgraded 1887 chassis included a manual leather shoe brake on the rear wheels.
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In 1895 the Michelin Brothers, Andre and Edouard (French), produced the first pneumatic car tire, fitting them to a Peugeot “L'Eclair” motor car in the same year. What type of braking system was used?
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The pneumatic tire however that could not be used with wooden shoe block brakes and a new method of braking was required.
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The first “external contracting brake” devices attempted to apply force by means of a steel strap or cable directly to the axle, to a drum fitted onto the axle or to the transmission shaft.
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A method that became known as a contracting “Band Brake” (sometimes referred to as an external drum brake) was employed during the late 1890s and early 1900s.
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A typically band brake consisted of a flexible metal band that was lined with friction material and wrapped around a drum attached around the car’s rear axle or, in some circumstances to a wheel’s hub.
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The band tightened around the drum to slow or stop the car when the driver depressed a foot pedal or operated a lever.
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An early method included the use of a wooden block inside a flexible contracting metal band.
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Metal bands lined with lead, cotton and camel hair were also tried.
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Another early device used strips of leather wrapped around one of the wheel hubs, which would, when a lever was pulled, tighten around the hub to slow the vehicle down.
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This “wrap-around brake” performed poorly, if at all, when wet.
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The disadvantages of these early band brake systems were:
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No protection from the elements and they suffered from a build up of dirt.
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Excessive wear to both the drum and the band. Maintenance every 200-250 miles (320-400 klm) was not uncommon.
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The band brake did not operate when the car was in reverse. Why not?
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Herbert Frood (British) is credited with inventing the first brake lining material in 1897; founding the Ferodo Company in the same year.
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Frood’s original brake lining material was made from laminated hair and bitumen.
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On an 1897 Roberts electric car (USA) leather-lined brakes were installed inside the housings of the two 2hp motors.
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In 1898, Elmer Ambrose Sperry (American) designed an electric car that had electromagnet front-wheel disc brakes.
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He fitted a large disc onto the hub of each of the two front wheels and electromagnets pressed smaller discs lined with a friction material against spots on the large rotating discs to stop the car.
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Springs retracted the spot discs when current was interrupted. How were the brakes applied? A switch connected to a foot or hand brake?
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In 1899 Gottlieb Daimler (German) wrapped a cable around a drum and anchored it to the chassis.
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The forward motion of the car tightened the cable, making it easier for the driver to pull the brake lever. It was the first, if basic application, of servo assisted braking.
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In 1901 Wilhelm Maybach (German) designed the first internal drum brake.
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Maybach’s brake drum used rollers to press a ring of friction material against the inside of a drum fitted on the rear axle.
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It was used on the Mercedes Simplex 40hp model (1902-09); the main hand brake acting on the drum brake with a secondary foot brake acting on the chain drive’s intermediate drive shaft. Was it used on other Mercedes models?
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A water sprinkling system cooled the hot zones of both brake systems when the brakes were applied.
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In 1902 Louis Renault (French) designed an internal drum brake that the modern version is based upon.
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Renault’s drum brake used two curved shoes (pads) fixed to a back plate with each pivoted at one end. The other ends rested on a cam.
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When the brake pedal was pressed, the cam forced the shoes apart and against the inside of the drum.
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In 1902 Ransom E. Olds (American) produced an external drum brake by wrapping a stainless steel band around a drum fitted on a car’s rear axle.
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On 1 December 1902 Frederick Lanchester (British) submitted an application for a patent for non-electric caliper-type automobile spot disc brake system.
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“This invention relates to an improved form of brake mechanism for power propelled vehicles and refers more particularly to an improved construction of road wheel brake”.
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Fredrick Lanchester was granted patent GB 190226407 on 15 October 1903.
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The brake pads were made of copper and the intense noise created by the metal-to-metal contact when the brakes were applied was a major problem.
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The copper brake pads also wore out much too quickly.
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In 1907 Herbert Frood (British) solved the noise problem when he lined the brake pads with asbestos that was woven into a loose fabric and impregnated with high melting point resin and varnish.
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The new asbestos pads were also more durable and had a much longer life than the copper ones, achieving up to 9,000 miles (15,000 klm).
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At the turn of the 2oth century roads were very crude and dirty and “internal” drum brakes kept out water and materials that could damage disc brakes.
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More importantly “internal” drum brakes required drivers to apply less pressure on the pedal compared to the early disc brakes.
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This was especially relevant prior to the introduction of hydraulic and power brake systems.
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For a combination of reasons it wasn’t until the late 1940s/early 1950s that car manufacturers started to fit disc brakes.
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Note 1: When brake pads (“shoes”) press on the outside of the drum the method is sometimes referred to as a “clasp brake”.
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Note 2: When a drum is pinched between two brake pads it is sometimes referred to as a "pinch drum brake".
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Power assisted brakes were first employed in 1903 when air brakes were fitted to a car called the Tincher that was developed by Thomas L Tincher (American).
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In 1903 four-wheel brakes were fitted to the Dutch Spiker 60/80 HP model.
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For further information on the history of brakes see Part 2, The Last 100 Years, Section 6.1 (Brakes).
