Front wheel drive
Front-wheel drive in connection with a front engine in motor vehicles is referred to as front-wheel drive . In contrast to the rear-wheel drive , the front-wheel drive is almost exclusively combined with a front-engine, the only exceptions are in commercial vehicles. Some front-wheel drive car models are offered with all-wheel drive as an alternative .
history
.jpg)
.jpg)
The first vehicle with front-wheel drive was built by the Viennese automobile workshop Gräf & Stift in 1898 . The problem of simultaneous steering and drive was only solved satisfactorily by the French company Tracta , which in the second half of the 1920s granted the license for its "Tracta" constant velocity joints to various manufacturers, including Zschopauer Motorenwerke J. S. Rasmussen ( DKW ), Stoewer and the Adlerwerke sold.
Such vehicles were first mass-produced in the USA from 1929 onwards by Ruxton and Auburn (model Cord L-29), followed in 1931 by Stoewer ( V 5 ) and shortly thereafter DKW ( F1 ) and 1932 Adler ( Trumpf ). From 1934, Citroën was also a pioneer in large-scale production of this drive technology in France with the Traction Avant and subsequent models.
After the war there were front-wheel drive cars in the GDR from Sachsenring and the Eisenach automobile plant (from 1953 when the IFA F9 was taken over ). In the Federal Republic of Germany there were such vehicles from DKW, Lloyd and Gutbrod as well as in Sweden from Saab from 1947. These vehicles had relatively small two- or three-cylinder engines that could still be accommodated cheaply in the engine compartment despite the front-wheel drive.
The final breakthrough for front-wheel drive was made possible in 1959 by the Mini presented by BMC , in which a transverse four-cylinder engine with a gearbox and front-wheel drive was combined for the first time in a production car . The transverse engine allowed a favorable use of space, so that the use of four-cylinder engines was now also rationally possible. The progressive concept was adopted rather hesitantly by other automakers. For example, from 1962 the Ford 12M came with front-wheel drive, but with a V4 engine to solve the space problem as an alternative. Some important manufacturers such as Opel and VW only switched to front-wheel drive in the 1970s.
Rear-wheel drive is still preferred in some of the upper-middle-class and luxury-class cars , including from BMW and Mercedes-Benz . One reason for this is the difficulty of installing large engines with eight or twelve cylinders across. In addition, a space-optimized and cost-effective design is not primarily important for such spacious cars. In addition, rear-wheel drive offers advantages in terms of driving behavior in powerful vehicles due to better traction on the road surface with good grip. As a result, some sports car manufacturers have stuck to rear-wheel drive, but they rarely use a front engine, including Porsche and Ferrari .
The moped of Velosolex was one of the few successfully built bicycles with front wheel drive . Front-wheel drive motorcycles such as the Megola and the Killinger & Freund motorcycle were also built, but could not establish themselves.
Sonderweg USA
In the USA there was a front-wheel drive racing car built by the American John Walter Christie as early as 1904 . The vehicle even held the world speed record over a mile for a short time. There was no commercialization, but in 1912 Christie brought a single-axle tractor onto the market, which was mounted on wagons instead of the front axle, thus replacing the horses. This axle was driven and steerable. The vehicle was mainly used by municipal fire departments, where it helped to extend the service life of ladder and syringe trolleys.
1929 published with the Cord L-29 and the Ruxton two large and luxurious vehicles series with rows - eight-cylinder engines and front wheel drive. Technical problems, a high price and the economic crisis prevented greater success. Cord built the last US front-wheel drive vehicle with the V8 model 810/812 from 1935 to 1937, until General Motors used this type of drive in 1966 with the Oldsmobile Toronado and in 1967 with the Cadillac Eldorado . Today it is also widespread in the USA.
Advantages and disadvantages of front-wheel drive
Vehicle concept
Front-wheel drive is the most common type of drive for vehicles up to the lower middle class. The drive unit can be installed in a comparatively compact manner in the remaining space between the wheel arches in the front end thanks to the transverse installation of the engine and transmission. Fewer components are required than with the standard drive. The production costs can be reduced by up to 15%. In the case of a transverse drive, the crankshaft and drive axle are parallel, which enables simple power transmission without expensive angular gear. The space available in the passenger compartment is more advantageous with this type of construction because there is no cardan tunnel . The front footwell does not need to be restricted by a transmission tunnel.
For in-line engines with more than four cylinders or engines with a large displacement, the front-wheel drive with a longitudinally installed engine is suitable. The front end or the front overhang must be designed to be relatively long. The arrangement with the engine at the front and the gearbox behind it ensures a comparatively high axle load and higher steering forces, but is suitable for all-wheel drive. The reverse arrangement (gearbox in front, engine behind) has not been used since the 1980s. It was widespread in the years before and after World War II . The front axle load and the front overhang is lower and the bonnet can be designed to be slippery and flat.
Engines were rarely installed lengthways above the axis with the gearbox below or next to it ( Oldsmobile Toronado , Saab 99 , VW K 70 ). This design is compact, but complex. The engine is usually steeply inclined so that the hood does not have to get too high.
Driving dynamics
Front-wheel drive vehicles with their high front axle load are generally good-natured and understeer . They are characterized by good traction on slippery roads and comparatively low sensitivity to cross winds. Payload or trailer operation worsen the traction on non-slip roads. With strong acceleration, the drive wheels are also relieved, which is why all-wheel drive is often used from the upper middle class.
So that no drive influences are noticeable in the steering, wheel suspensions with a small disruptive force lever arm are required. The slightly lower wheel angle increases the turning circle compared to the rear-wheel drive.
Because of the low rear axle load, the cornering force of the rear tires can be overwhelmed when the accelerator is released ( load change ) and the rear can break out. These and other differences between front-wheel drive and rear-wheel drive have become significantly smaller today (2019) thanks to tires, chassis settings and control systems. So are z. For example, in the test maneuver 18-meter slalom by auto motor und sport , front-wheel drive vehicles can also be found in the front field.
Examples of front-wheel drive cars
.JPG)
- The Stoewer V 5 was the first series front-wheel drive car in Germany. It was designed, built and tested in 1930. It went into series production in January 1931 and was exhibited together with the DKW F1 at the IFA in February . The DKW went into series production in May 1931.
- The first large-scale front-wheel drive vehicle was the Citroën Traction Avant , which was manufactured from 1934 to 1957. Since then, front-wheel drive has been common at Citroën, and from the 1960s also at Renault and the Italian large-scale manufacturers.
- almost all Volkswagen since the discontinuation of the VW T3 in 1992 (except Crafter, Amarok and syncro or 4motion models)
- almost all competing models in the compact class such as the Opel Astra , Ford Focus etc., the only exception being the BMW 1 Series until the end of June 2019
- almost all current small cars (except Smart Fortwo , Renault Twingo and a few small all-wheel drive cars)
- almost all vehicles from Audi (except Quattro models)
- almost all Opel vehicles since 1982 (except Manta , Rekord , Omega , Commodore , Senator , Monza , Speedster , the GT from 2007 , Campo and all-wheel drive models)
- almost all compact vehicles from General Motors USA since the X-Bodies from 1979
Trivia
- The largest engine that has ever been installed in a front-wheel drive passenger car was a four-cylinder V-engine with an enormous 19,881 cm³ displacement. John Walter Christie used it unsuccessfully in the 1907 French Grand Prix. This is also the largest engine ever used in a Grand Prix.
- The Cadillac Fleetwood Eldorado from model years 1971 to 1978 is considered to be the largest mass-produced front-wheel drive passenger car .
Other drive variants
|
Differentiation according to motor position: |
Differentiation according to drive axes:
|
Differentiation according to drive unit:
|
See also
literature
- Single or double joint in front-wheel drive. In: Motor vehicle technology 2/1959, pp. 60–66.
- Hand-Roland Zitka: Long live the front-wheel drive. Article in the FAZ from November 25, 2006.
- Hans Jörg Leyhausen: The master's examination in the automotive trade part 1. 12th edition. Vogel Buchverlag, Würzburg 1991, ISBN 3-8023-0857-3 .
- Hans-Hermann Braess, Ulrich Seiffert: Vieweg manual automotive technology. 2nd Edition. Friedrich Vieweg & Sohn, Braunschweig / Wiesbaden 2001, ISBN 3-528-13114-4 .
- Beverly Rae Kimes: The Standard Catalog of American Cars. 2nd Edition. Krause Publications, Iola WI 54990 (USA) 1989, ISBN 0-87341-111-0 .
Individual evidence
- ↑ Bernhard Heissing, Metin Ersoy, Stefan Gies (eds.): Chassis manual : Basics, driving dynamics, components, systems, mechatronics, perspectives . 3. Edition. Vieweg + Teubner, 2011, p. 11 ( limited preview in Google Book search).
- ↑ BMW Group Plant Leipzig starts production of the new BMW 1 Series. In: press.bmwgroup.com. July 2, 2019, accessed September 18, 2019 .
- ^ Auto Catalog No. 20 (1976/77), p. 36.