Windscreen wiper
A windshield wiper is a device for cleaning the front or rear window of a motor vehicle, aircraft, ship or rail car. Wipers consist of wiper arm, wiper blade and drive. The wiper blade is fitted with a rubber profile, which pushes interfering moisture or dirt on the disc, and the vehicle occupants provides better visibility to the outside.
Construction
Conventional wipers are made of a wiper made of metal, which is attached to the wiper shaft. A hinge allows it to fold the windshield wiper from the glass. The flat plates of the automobiles of earlier generations sufficient as a rigid metal bar wiper blade in which a rubber profile was clamped. For on the today usual curved automotive glass manufacturers have divided the blade into multiple segments of joints, the press the rubber profile on the glass. For the uniform distribution of the contact pressure two thin elastic metal inserts provide rubber profile. In addition, non-segmented flat wiper blades (also called Aero wipers ) on the market.
Drive
General windscreen wipers are powered by one or more electric motors, between the classical rotary motors ( ie rotating electric motors) and reversing motors must be distinguished. The former need a rod or lever mechanism, so that a wiping motion arises in the other corresponds to the wiping motion of the motor direction. Reversing motors need in addition to the wiper lever a complex control unit. Advantage of these systems are numerous comfort functions (eg wiping after washing, tear- free release of the wiper blades with frost, etc. ), do not provide the conventional systems.
Commercial Vehicles in part wiper systems with pneumatic actuator. For example, the wiper on the S-Bahn line are 420 operated with compressed air. They can each be controlled individually and have to part no fixed parking position. Rather, it depends on the "ability" of the operator where the wiper comes to stand. If he should be in the field of view, again a small amount of air pressure must be readjusted so that it continues to slip a piece.
Load distribution
The Ortscheit mechanism (English Whippletree ) ensures through a tree-like structure for a more even distribution of pressure on the windshield.
Arrangement
Co-rotating wiper, mirrored, for example: Mercedes -Benz W 140
Opposing wiper, eg: Mercedes -Benz W 115, VW Sharan
Opposing wiper, resting above the Seat Altea
Einhebelwischer, Sportwiper eg: Renault Twingo I, Citroën CX
Einhebelwischer with stroke control, such as: Mercedes -Benz W 124
Parallelogrammwischer, Pantographenwischer eg standard bus, MAN gl, Porsche 904 (single wiper )
Triple wipers, truck, eg: MAN, Morgan Aero 8
Two independent wiper on shared disks ( out of date), eg: Magirus -Deutz Rundhauber
Two independent wiper on shared disks, hanging (out of date ), eg Hummer H1
In addition to the conventional arrangement of two equal-sized, usually standing wipers (axis below the disk ), there are solutions with hanging arrangement and with three wipers for thick slices or even a single arm wiper covering large flat washers. For such windshield wiper, two different sizes are used. Technically -consuming are parallelogram or Doppelarmscheibenwischer with an always upright wiper blade which barely disturbs the air flow on the one hand and on the other, for example, cleans the large front windows of buses in almost constant height almost to the frame.
To improve the aerodynamics and the aerodynamic drag coefficient of vehicle bodies wiper arms on many vehicles are fitted with a deep -drawn front window since the beginning of the 1980s that they completely or at least partially located in the original position below the rear edge of the bonnet and little or no cause air turbulence. Such recessed windscreen wipers had Opel Kapitän, Admiral and Diplomat in 1969. Since the late 1990s are mainly in small cars such as the Smart, the back to find Twingo or the mini does not hide mounted wiper arms.
Another type are opposite wiper. In Seat Altea about the wiper blades are at rest under the cover of the A-pillar.
Parallelogrammwischer on bus
And ... on Porsche 904
Slinger and linear wipers on a ship
Wiper of the ICE 3
One particular method to free slices of rain, the slinger used in ships. Another type for ships are linear wipers. The windshield wipers running in a track above the wheels back and forth and then wipe the entire surface.
Operation
In most modern car models in the engine of a screen wiper with a lever on the steering column, a so-called steering column switch, or via a satellite operation is switched.
In order for the wipers rain - or does not begin to rub against the wheel snowfall in low, can the drive in today's vehicles be interrupted by an interval switch. There are also rain sensors that detect how much the disc is wetted by rain or snow, and automatically regulate the use of windshield wipers.
History
In November 1903, the American Mary Anderson was granted a patent on the first functioning windshield wiper system in the world. The patent (U.S. 743.801 ) was handed to her on November 10, 1903 by the " U.S. Patent Office ". Anderson's device consisted of a steering wheel mounted in close lever, with which the driver has put on the windshield if necessary, a swing arm suspension with a rubber sheet in movement, then returned again to the starting position.
1905 reported Henry of Prussia, brother of Emperor Wilhelm II, the first German to such a system for a patent. On 24 March 1908 he was granted a patent for it. He was driving at the time an Opel. The windshield wiper was also hand-operated.
In 1926 the company introduced its first Bosch appliance before, in which an electric motor could commute a wiper arm with rubber lip on the car window to push away the rainwater. Until then, possessed cars, if at all, through a manually operated " Abstreiflineal ", or wiper with mechanical or "vacuum" drive with the great disadvantage that at slow speed or even while waiting at a traffic light the wiper slowly or not at all stopped moving and thus the driver had to manually boost.
1964 invented Robert Kearns, professor of engineering at Wayne State University, the intermittent wiper. Kearns followed with his invention of the human eyelid that automatically short-circuits in an interval of a few seconds and opens again. After he received the first of more than 30 patents in 1967, he proposed the model before the automaker Ford Motor Company. This built in 1969 but its own interval windshield wiper systems without Kearns to participate in the profits. Other automakers followed within a few years. Kearns struggled to a patent infringement lawsuit against Ford and 26 other automakers. In 1990, he rejected a comparison with Ford and complained on. In July 1990, a federal court closed the case and ordered Ford to make a payment of 10.2 million U.S. $ for unintentional patent infringement. In December of the same year a condemnation of Chrysler followed to a payment of 20 million U.S. $.
In 1999, Robert Bosch GmbH is unveiling the hingeless flat bar wipers ( aero twin) on the market, which is now provided on almost all new vehicles.
Others
The German artist Herbert Zang (1924-2003) used, among other things wiper to apply color.