Windshield Wiper

The windshield wiper is a device used to clear rain and debris from a windshield. Almost every major vehicle is equipped with wipers, and most of the time they are a legal requirement. The wiper usually consists of an arm that pivots at one end with a long rubber blade attached to the other. The blade swings back and forth over the glass clearing water from the surface. Usually the speed can be adjusted with several different speeds. Most autos have two synchronized radial type arms, while many commercial vehicles use one or more pantograph arms.

Mary Anderson is credited with the invention of the wiper when she patented the idea in 1903. By 1916 all American cars had them. James Henry patented an idea in 1903 for two brushes to move up and down clearing the glass. His invention was patented in the UK.
Tri-Continental Corporation introduced the first windshield wiper, Rain Rubber. Trico Products is one of the world’s leading manufacturers of windshield wiping systems with wiper plants on five continents.

William M. Folberth was granted a patent in 1922 for an automatic windscreen wiper apparatus, the world’s first. Trico later purchased Folberth’s company and the vacuum-powered system quickly became standard on all Autos. The first time that operating wipers automatically for two or three passes when the washer button was pressed was in 1950s. Then a vacuum cylinder was used but now and electronic timer is used.

The first intermittent wiper with an adjustable delay between wipes was introduced in 1969. Robert Kearns is recognized as the inventor of this system. Most wipers today are powered by an electric motor through a series of mechanical components. However, early wipers were driven by a vacuum motor. However the vacuum power was nearly non-existent when the throttle was wide-open. This was overcome by using a combined fuel/vacuum booster pump. Some cars avoided the problem all together by using a hydraulic driven wiper.

A lot of commercial vehicles us pantograph-based wipers. The wipers feature two arms for each blade with the blade assembly itself supported on a horizontal bar connecting the two arms. This system allows the wiper to cover more of the windshield although it may have to “park” in the middle of the windshield blocking the drivers view.
Mercedes-Benz created a system called the Monoblade which swept out a W shaped path. Some vehicles have small wipers on the headlights although these have been mostly replaced with a powerful jet spray. Some vehicles have wipers on the back window as well. These rear wipers were first implemented in the 1970s.

Most windshield wipers work with washer fluid (usually containing water and detergent) that is dispensed from a small nozzle mounted on the hood. Many modern vehicles are equipped with driver-programmable intelligent windshield wipers that can detect the presence of rain using a sensor. This sensor automatically changes the speed of the blades according to the amount of rain.