u.s. patent and trademark office2007_1_7

Mary anderson, of Birmingham, Alabama, is usually credited with inventing the windshield wiper. In 1903, during a visit to New York City, she took a streetcar during a snowstorm and saw the driver repeatedly stop his car to go outside and clean its front glass. Anderson went home and designed a wiper mounted on a spindle that ran through a hole in the windshield frame and connected to a handle inside the vehicle. A counterweight and spring mechanism kept the rubber blade pressed against the glass.

Anderson’s device was meant for streetcars, not automobiles, very few of which had windshields in 1903. Even after windshields became common, toward the end of the decade, wipers were not considered necessary, since most cars were still open to the air and stayed in the garage when it rained. But as driving became a routine activity for the masses instead of a recreation for the wealthy, automobiles had to be usable in all kinds of weather.

In 1917 a Buffalo, New York, company called Tri-Continental, or Tri-Co for short (the predecessor of today’s Trico, the world’s largest manufacturer of windshield wipers), began marketing its Rain Rubber. This hand-operated device was a rubber blade attached to a handle that a driver could stick through the gap between the upper and lower parts of a windshield. After World War I, car manufacturers began sealing this gap with a rubber gasket, so in the early 1920s Tri-Co marketed its Crescent Cleaner, which was mounted on the upper windshield. It was still hand-operated.

Around the same time, Tri-Co introduced the first automatic wiper, which was powered by the partial vacuum created by the engine’s intake manifold. Cadillac adopted it as standard equipment in 1922. Unfortunately, the speed of the wipers depended on how hard the engine was working; they might stop altogether when the car climbed a steep grade. Electric wiper drive would appear on luxury cars in 1926, though vacuum motors, which were sturdy and simple, persisted through the 1960s on workhorse vehicles such as jeeps. Meanwhile, Tri-Co remained a leader in the field, introducing, among other innovations, a five-ply blade to channel water efficiently in 1928, the first dual-wiper system in 1929, washer fluid in 1936 (with a dispensing system called “Two Little Squirts”), and rear wipers in 1959.

These and other advances made driving in the rain much safer, but a problem remained: The wipers kept going monotonously back and forth without any pause. You could vary the speed, but even so, there was always a wiper in your field of vision, and the blades often scraped across a windshield that was nearly dry. The resultant friction made an annoying sound and tore up the blades’ edges.

A solution that occurred to a number of inventors was an intermittent system —one that would wipe, pause for a few seconds, then wipe again. In the late 1950s an engineer at Ford built one whose motor was turned on and off by the thermal expansion of a bimetallic coil. It didn’t work very well, and in cold weather it didn’t work at all. In the early 1960s Trico engineers developed a system in which vacuum suction compressed a spring, which closed a switch. It was much more complicated than the old constant-wipe vacuum systems and had similar problems functioning when the engine was at full throttle.

The true solution came from Robert Kearns, an engineering professor at Wayne State University, in Detroit. The road to intermittent wipers began on his wedding night in 1953, when an errant champagne cork shot into his left eye, which eventually went almost completely blind. Nearly a decade later Kearns was driving his Ford Galaxie through a light rain, and the constant movement of the wiper blades irritated his already troubled vision. He got to thinking about the human eye, which has its own kind of wiper, the eyelid, that automatically closes and opens every few seconds. Why couldn’t windshield wipers work the same way?

In 1963 he built an intermittent wiper system using off-the-shelf electronic components and offered it to Ford. The interval between wipes was determined by the rate of current flow into a capacitor. When the charge in the capacitor reached a certain voltage, the capacitor discharged, activating the wiper motor for one cycle. After extensive testing, Ford executives decided to offer Kearns’s intermittent wipers as an option on the company’s Mercury line beginning with the 1969 models. Kearns assigned his patent rights to the Tann Corporation, a Detroit tool-and-die company, which planned to sell the wipers to Ford and other carmakers. Tann paid Kearns $1,000 a month to continue improving his design.

Kearns had refused to tell Ford how his system worked; the prototype was sealed in a red box labeled do not open. Then one executive told him that since windshield wipers are a safety feature, he was legally required to explain their functioning. Kearns did so. A few months later he was told that Ford had changed its mind and chosen a different electronic intermittent-wiper system that it had developed in-house. Kearns wanted Tann to sue, but the company depended on Ford for a big chunk of its business, so it was not about to make waves.

Kearns moved on, taking a job with the National Bureau of Standards and moving his family to Maryland. Then, in 1976, he took apart a wiper control that one of his sons had bought. He found that it was basically the same system he had invented. Kearns promptly had a nervous breakdown, fled his home, and spent several weeks in a psychiatric ward. When he emerged, his hair had turned white.

He sued Ford for patent infringement in 1978, later suing Chrysler as well and making plans to sue General Motors and foreign manufacturers. It took 12 years for the Ford suit to reach trial, as Kearns spurned repeated offers to settle. His wife left him in 1980, and a bitter divorce suit ensued; he spent five weeks in jail in 1990 for nonpayment of alimony.

Ford’s legal team argued that Kearns’s patents were overly broad and therefore invalid. As Ted Daykin, a former Ford engineer, told The New Yorker in a 1993 article, “An electronic timing device was an obvious thing to try next. How can you patent something that is in the natural evolution of technology?” The intermittent wiper, according to Daykin, was really the work of dozens of anonymous engineers at Ford, Trico, and other firms.

In the end, Kearns achieved the vindication he craved—and wrecked his life. He won $10.2 million from Ford in 1990 and $18.7 million from Chrysler in 1995, though both juries determined that the companies had not intentionally infringed on his patents. Along the way he had run up huge legal bills, so he needed lots more money to continue his fight against GM, Mercedes, and more than two dozen other companies. Near the end of the Chrysler litigation, he fired his fifth law firm and decided to represent himself. The work overwhelmed him, and when he began missing deadlines, the remaining suits were dismissed. He retired, but his patent rights remained an obsession until Alzheimer’s disease overtook him. In 2005 Robert Kearns died in a Maryland nursing home.