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43-549: The term was probably first coined by Karl von Drais in French as vélocipède for the French translation of his advertising leaflet for his version of the Laufmaschine , also now called a ' dandy horse ', which he had developed in 1817. It is ultimately derived from the Latin velox , veloc- 'swift' + pes , ped- 'foot'. The term 'velocipede' is today mainly used as a collective term for

86-568: A ring gear is driven by a pinion gear connected to the transmission. The functions of this design are to change the axis of rotation by 90 degrees (from the propshaft to the half-shafts) and provide a reduction in the gear ratio . The components of the ring-and-pinion differential shown in the schematic diagram on the right are: 1. Output shafts ( axles ) 2. Drive gear 3. Output gears 4. Planetary gears 5. Carrier 6. Input gear 7. Input shaft ( driveshaft ) An epicyclic differential uses epicyclic gearing to send certain proportions of torque to

129-655: A break in the track, and flagged down a night freight train, thus preventing a possible accident. The railroad rewarded his efforts by bankrolling his invention. George Sheffield obtained the patent for his device in 1879, calling it a "velocipede hand car." Originally manufactured by G.S. Sheffield & Co. and later manufactured by Fairbanks, Morse & Company , the Sheffield velocipede remained in use up to World War II. Karl von Drais Karl Freiherr von Drais (full name: Karl Friedrich Christian Ludwig Freiherr Drais von Sauerbronn ; 29 April 1785 – 10 December 1851)

172-408: A commemorative postage stamp, a semipostal 50 Pf+25 Pf surcharge, in remembrance of the 200th anniversary of Karl Drais's birthday. On 29 April 2010, Google celebrated 225th Birthday of Karl Drais with a doodle. In 2017, Germany issued a commemorative postage stamp (0.70 Euro) in remembrance of the 200th anniversary of Karl Drais's first run of his "running machine" on 12 June 1817. The stamp shows

215-401: A common shaft. This forces both wheels to turn in unison, regardless of the traction (or lack thereof) available to either wheel individually. When this function is not required, the differential can be "unlocked" to function as a regular open differential. Locking differentials are mostly used on off-road vehicles, to overcome low-grip and variable grip surfaces. An undesirable side-effect of

258-418: A differential, which allows the two wheels to rotate at different speeds. The purpose of a differential is to transfer the engine's power to the wheels while still allowing the wheels to rotate at different speeds when required. An illustration of the operating principle for a ring-and-pinion differential is shown below. A relatively simple design of differential is used in rear-wheel drive vehicles, whereby

301-497: A framework of wrought iron . As the name implies it was extremely uncomfortable, but the discomfort was somewhat ameliorated by a long flat spring that supported the saddle and absorbed some of the shocks from rough road surfaces. The boneshaker also had a brake  – a metal lever that pressed a wooden pad against the rear wheel. The front wheel axle ran in lubricated bronze bearings, and some had small lubrication tanks that would wick oil from soaked lamb's wool into

344-400: A gear ratio between the input and output shafts (called the "axle ratio" or "diff ratio"). For example, many differentials in motor vehicles provide a gearing reduction by having fewer teeth on the pinion than the ring gear . Milestones in the design or use of differentials include: During cornering, the outer wheels of a vehicle must travel further than the inner wheels (since they are on

387-427: A land surveyor on the fazenda of Georg Heinrich von Langsdorff . In 1827, he returned to Mannheim . Three years later in 1830, Drais's father died and the younger Drais was mobbed by jealous rivals. In 1839, after surviving a murderous attack in 1838, he moved to the village of Waldkatzenbach in the hills of Odenwald and remained there until 1845. During this period, he invented the railway handcar (later known as

430-405: A larger radius). This is easily accommodated when the wheels are not connected , however it becomes more difficult for the drive wheels , since both wheels are connected to the engine (usually via a transmission). Some vehicles (for example go-karts and trams ) use axles without a differential, thus relying on wheel slip when cornering. However, for improved cornering abilities, many vehicles use

473-507: A patent in January 1818. This was the world's first balance bicycle and quickly became popular in both the United Kingdom and France, where it was sometimes called a draisine (German and English), draisienne (French), a vélocipède (French), a swiftwalker , a dandy horse (as it was very popular among dandies ) or a Hobby horse . It was made entirely of wood and metal and despite

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516-412: A pointer which constantly pointed to the south, no matter how the chariot turned as it travelled. It could therefore be used as a type of compass . It is widely thought that a differential mechanism responded to any difference between the speeds of rotation of the two wheels of the chariot, and turned the pointer appropriately. However, the mechanism was not precise enough, and, after a few miles of travel,

559-494: A regular ("open") differential is that it can send most of the power to the wheel with the lesser traction (grip). In situation when one wheel has reduced grip (e.g. due to cornering forces or a low-grip surface under one wheel), an open differential can cause wheelspin in the tyre with less grip, while the tyre with more grip receives very little power to propel the vehicle forward. In order to avoid this situation, various designs of limited-slip differentials are used to limit

602-547: A result, on 12 January 1818, Drais was awarded a grand-ducal privilege ( Großherzogliches Privileg ) to protect his inventions for 10 years in Baden by the younger Grand Duke Karl . Grand Duke Karl also appointed Drais professor of mechanics . This was merely an honorary title, not related to any university or other institution. Drais retired from the civil service and was awarded a pension for his appointment to professor of mechanical science. In 1820, trouble overtook Drais when

645-456: A single person, which came to be known as a "railway velocipede" or "railroad velocipede". The three-wheel hand-pump rail car's invention is credited to George S. Sheffield of Three Rivers, Michigan. Legend has it that because of inadequate train service to his home, Sheffield built a simple three-wheel car, allowing him to commute 11 kilometres (7 mi) between home and work without having to walk. While so traveling one evening, he discovered

688-454: A type of mechanical analogue computer, were used from approximately 1900 to 1950. These devices used differential gear trains to perform addition and subtraction. The Mars rovers Spirit and Opportunity (both launched in 2004) used differential gears in their rocker-bogie suspensions to keep the rover body balanced as the wheels on the left and right move up and down over uneven terrain. The Curiosity and Perseverance rovers used

731-408: The draisine ). Finally, he moved back to his place of birth, Karlsruhe . In 1849, and still a fervent radical, Drais gave up his title of Baron and dropped the "von" from his name. Subsequently, after the revolution collapsed, he was in a very bad position. The royalists tried to have him certified as mad and locked up. His pension was confiscated to help to pay for the "costs of revolution" after it

774-449: The "correct" time, so an ordinary clock would frequently have to be readjusted, even if it worked perfectly, because of seasonal variations in the equation of time. Williamson's and other equation clocks showed sundial time without needing readjustment. Nowadays, we consider clocks to be "correct" and sundials usually incorrect, so many sundials carry instructions about how to use their readings to obtain clock time. Differential analysers ,

817-467: The 'Diploma of honour' at the Exposition Universelle (1878) (World's Fair). During the 1870s advances in metallurgy led to the development of the first all-metal velocipedes. The pedals were still attached directly to the front wheel, which became larger and larger as makers realised that the larger the wheel, the farther you could travel with one rotation of the pedals. Solid rubber tires and

860-426: The 1880s favoured the less risky tricycle. Many innovations for tricycles eventually found their way into the automobile , such as rack and pinion steering , the differential , and band brakes , the forerunners to drum brakes . Boneshaker (or bone-shaker) is a name dating from the 1860s for the first type of true bicycle with pedals , which were called velocipedes by their manufacturers. "Boneshaker" referred to

903-614: The Sun and Moon position pointers. The ball was painted black and white in hemispheres, and graphically showed the phase of the Moon at a particular point in time. An equation clock that used a differential for addition was made in 1720. In the 20th century, large assemblies of many differentials were used as analogue computers , calculating, for example, the direction in which a gun should be aimed. Chinese south-pointing chariots may also have been very early applications of differentials. The chariot had

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946-514: The United States, and even Calcutta banned its use, which ended its vogue for decades. Drais also invented the earliest typewriter with a keyboard (1821). He later developed an early stenograph machine which used 16 characters (1827), a device to record piano music on paper (1812), the first meat grinder (1840s), and a wood-saving cooker including the earliest hay chest . He also invented two four-wheeled human powered vehicles (1813/1814),

989-516: The bearings to help them run smoothly. Like the High Wheel bicycles that became popular later in the 19th century, boneshakers were front-wheel drive, but in comparison they had smaller wheels (only about 1 m), and were heavy, with a lightweight model weighing 14 kilograms (30 lb) or more. Railroads in North America often made use of a three-wheeled handcar designed to be operated by

1032-539: The carrier is rotated (by the input torque), the relationship between the speeds of the input (i.e. the carrier) and that of the output shafts is the same as other types of open differentials. Uses of spur-gear differentials include the Oldsmobile Toronado American front-wheel drive car. Locking differentials have the ability to overcome the chief limitation of a standard open differential by essentially "locking" both wheels on an axle together as if on

1075-470: The condition of the roads at the time was sometimes ridden for long distances. It was almost 40 years until "velocipede" came into common usage as a generic term, with the launch of the first pedal -equipped bicycle , developed by Pierre Michaux , Pierre Lallement and the Olivier brothers in the 1860s. The Michaux company was the first to mass-produce the velocipede, from 1857 to 1871. That French design

1118-408: The dial could be pointing in the wrong direction. The earliest verified use of a differential was in a clock made by Joseph Williamson in 1720. It employed a differential to add the equation of time to local mean time , as determined by the clock mechanism, to produce solar time , which would have been the same as the reading of a sundial . During the 18th century, sundials were considered to show

1161-480: The difference in power sent to each of the wheels. Torque vectoring is a technology employed in automobile differentials that has the ability to vary the torque to each half-shaft with an electronic system; or in rail vehicles which achieve the same using individually motored wheels. In the case of automobiles, it is used to augment the stability or cornering ability of the vehicle. Non-automotive uses of differentials include performing analogue arithmetic . Two of

1204-406: The different forerunners of the monowheel , the unicycle , the bicycle , the dicycle , the tricycle and the quadracycle developed between 1817 and 1880. Velocipede refers especially to the forerunner of the modern bicycle that was propelled, like a modern tricycle, by cranks, i.e. pedals , attached to the front axle before the invention of geared chains and belt and shaft drives powering

1247-474: The differential's three shafts are made to rotate through angles that represent (are proportional to) two numbers, and the angle of the third shaft's rotation represents the sum or difference of the two input numbers. The earliest known use of a differential gear is in the Antikythera mechanism, c. 80 BCE, which used a differential gear to control a small sphere representing the Moon from the difference between

1290-503: The extremely uncomfortable ride, which was caused by the stiff wrought-iron frame and wooden wheels surrounded by tires made of iron . The so-called "boneshaker" was invented in the 1860s in France and first manufactured by the Michaux company from 1867 to 1869 , the time of the first bicycle craze . The boneshaker was copied by many others during that time. It fell out of favor after

1333-401: The front axle and the rear axle in an all-wheel drive vehicle. An advantage of the epicyclic design is that it is relatively compact width (when viewed along the axis of its input shaft). A spur-gear differential has an equal-sized spur gears at each end, each of which is connected to an output shaft. The input torque (i.e. from the engine or transmission) is applied to the differential via

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1376-458: The long spokes of the large front wheel provided a much smoother ride than its predecessor. This type of velocipede was the first one to be called a bicycle ("two wheel"), and its shape led to the nickname penny-farthing in the United Kingdom. They enjoyed a great popularity among young men in the 1880s who could afford them. While young men were risking their necks on the high wheels, ladies and dignified gentlemen such as doctors and clergymen of

1419-492: The machine plus as its shadow, a bicycle. Differential (mechanical device) A differential is a gear train with three drive shafts that has the property that the rotational speed of one shaft is the average of the speeds of the others. A common use of differentials is in motor vehicles , to allow the wheels at each end of a drive axle to rotate at different speeds while cornering. Other uses include clocks and analogue computers . Differentials can also provide

1462-578: The political murder of the author August von Kotzebue was followed by the beheading of the perpetrator, Karl Ludwig Sand . In 1822, Drais was a fervent liberal who supported revolution in Baden . Drais's conservative father, as the highest Judge of Baden , had not entered a plea for pardon in the beheading of Karl Ludwig Sand , and the younger Drais was mobbed by the student partisans everywhere in Germany due to his family ties. Therefore, Drais emigrated to Brazil where he lived from 1822 to 1827, and worked as

1505-535: The rear. Among the early velocipedes there were designs with one, two, three, four, and even five wheels. Some two-wheeled designs had pedals mounted on the front wheel, while three- and four-wheeled designs sometimes used treadles and levers to drive the rear wheels. The earliest usable and much-copied velocipede was created by the German Karl Drais and called a Laufmaschine (German for "running machine"), which he first rode on June 12, 1817. He obtained

1548-418: The rotating carrier. Pinion pairs are located within the carrier and rotate freely on pins supported by the carrier. The pinion pairs only mesh for the part of their length between the two spur gears, and rotate in opposite directions. The remaining length of a given pinion meshes with the nearer spur gear on its axle. Each pinion connects the associated spur gear to the other spur gear (via the other pinion). As

1591-457: The second of which he presented in Vienna to the congress carving up Europe after Napoleon 's defeat. In 1842, he developed a foot-driven human powered railway vehicle whose name " draisine " is used even today for railway handcars. Drais was unable to market his inventions for profit because he was still a civil servant of Baden , even though he was being paid without providing active service. As

1634-427: The summer of 1869 and was replaced in 1870 with the type of bicycle called "ordinary", "high-wheel", or " penny-farthing ". Few original boneshakers exist today, most having been melted for scrap metal during World War I. Those that do surface from time to time command high prices, typically up to about $ 5,000 US. The construction of the boneshaker was similar to the dandy horse : wooden wheels with iron tires and

1677-523: Was a distance of about 7 kilometres (4.3 mi). The round trip took him a little more than an hour but may be seen as the big bang for horseless transport. However, after marketing the velocipede, it became apparent that roads were so rutted by carriages that it was hard to balance on the machine for long, so velocipede riders took to the pavements (sidewalks) and moved far too quickly, endangering pedestrians. Consequently, authorities in Germany, Great Britain,

1720-505: Was a noble German forest official and significant inventor in the Biedermeier period . He was born and died in Karlsruhe . He is seen as "the father of the bicycle". Drais was a prolific inventor , who invented the Laufmaschine ("running machine"), also later called the velocipede , draisine ( English ) or draisienne ( French ), also nicknamed the hobby horse or dandy horse . This

1763-480: Was his most popular and widely recognized invention. It incorporated the two-wheeler principle that is basic to the bicycle and motorcycle and was the beginning of mechanized personal transport. This was the earliest form of a bicycle, without pedals. His first reported ride from Mannheim to the "Schwetzinger Relaishaus" (a coaching inn , located in "Rheinau", today a district of Mannheim) took place on 12 June 1817 using Baden's best road. Karl rode his bike; it

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1806-563: Was sometimes called the boneshaker, since it was also made entirely of wood, then later with metal tires. That in combination with the cobblestone roads of the day made for an extremely uncomfortable ride. These velocipedes also became a fad, and indoor riding academies, similar to roller rinks, could be found in large cities. In 1891 L'Industrie Vélocipédique (Cycling Industry) magazine described 'La Société Parisienne de constructions Velo' as 'the oldest velocipede manufacturer in France', having been founded in 1876 by M. Reynard, and awarded

1849-533: Was suppressed by the Prussians . Drais's undoing had been the fact that he had publicly renounced his noble title in 1848, and adopted the name "Citizen Karl Drais" as a tribute to the French Revolution . Karl Drais died penniless on 10 December 1851 in Karlsruhe . The house in which he lived last is just two blocks away from where at that time a young Carl Benz was raised. In 1985, West Germany issued

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