BACKYARD INVENTORS; How to 'see' what doesn't exist (yet)

Before an invention can be built of steel or plastic, it must first take shape in someone's imagination. Inventors describe how they break free from ''object-centered thinking'' to explore new possibilities.

The story began, apparently, when he crawled under a car in Harbin, China, sometime in the 1920s. Hardly ten, sprawled in the dust, the young Jacob Rabinow peered at the undercarriage and saw what he calls ''a wonderful thing.''

Unlike a wagon, the wheels weren't mounted on solid axles. Each turned separately - a simple arrangement allowing far freer motion.

''The idea fascinated me,'' he says. ''I thought, what a wonderful invention. Imagine not using a single axle for two wheels.''

This is not the sort of thing your average child notices - but then again, how many have a chance to go flopping around under Asian autos? Especially after having moved from Siberia in the first place. That moment, says Mr. Rabinow, was when he realized inventions can be art - elegant, witty solutions of unexpected simplicity; with a fresh tang to them, like sherbet on the tongue.

Inventors love ideas. They always want to know how something works. They adore fixing things and rigging up little gadgets and advising you how to improve the airflow through your attic, even if you didn't ask.

''An inventor is really a critic,'' says Richard Onanian, an inventing consultant. ''He's trying to right a world that's gone wrong.''

Why do they appreciate machines? What is the source of their tinkering ability? Where do their ideas come from?

* * *

Ka-thunk, ka-thunk. Rattle. Ka-thunk, kaching.

Jacob Rabinow, inventor extraordinaire, The Man Who Has Two Hundred and Seventeen Patents, is fiddling with a small machine. It is a box, built in the pre-plastic era, with keys that push downwards, twirling an arm on the side. Hooked to a modern stereo, it reveals itself: an old Zenith pushbutton tuner. Ka-thunk: Rabinow pushes a key, and the stereo plays jazz. Ka-ching: He pushes another, and the dial moves to a classical station.

''Those buttons I like very much,'' he says. ''I bought it for 50 cents in a junk shop in New York. It isn't complicated, just beautiful. It does the thing it's supposed to do with a minimum number of parts, like a good poem.''

Rabinow is a lively man who often stops in mid-sentence, exiting off his main stream of thought to bound away on tangents that interest him. (''Do you know how to take paneling off the wall without splitting it? Drive the nailhead right through.'') He was born in Kharkov, Russia, and passed through China on his way to the United States, where he moved with his family at the age of 11. After becoming a US citizen, he garnered several degrees in electrical engineering (from City College of New York) and moved to Washington, where he became a government scientist. After 16 years of inventing for the National Bureau of Standards (one result: the propellor fuse used on World War II bombs) he quit to market ideas on his own.

Among other things, he invented a magnetic clutch for cars, still used today in Subarus. He designed an automatic letter-sorter for the post office, a pick-proof lock, lane markers, and a device that enables one to read the label on a turning record. He developed the first ''reading machine'' capable of recognizing printed numbers - used, for example, to sort bank checks automatically. His patents on the device were sold to Control Data Corp. for half a million dollars, though most of that money disappeared in developing a straight-armed phonograph.

Like most inventors, Rabinow has filled his house with clever touches. The upstairs workshop has speaker holes so he can talk through the wall to his wife. The living room desk has a typewriter that pops out of a drawer, and Rabinow is currently trying to motorize one of his wife's granite sculptures. Visitors typically react to such ingenious devices with a chuckle, a grin, the statement ''my, that's really something.''

''Invention is a logical solution that's unexpected, like the punchline of a joke,'' says Rabinow. ''(In that way) inventions are very funny sometimes.''

This is one side, he claims, of the emotional reactions that make inventing an art.

''If a pursuit excites people, if sophisticated observers get an emotional kick, then it becomes an art form,'' he says. ''I have trouble explaining this to artists. To ask them to appreciate the beauty of a push-button tuner is very difficult.''

One day, curious to see whether his ideas came in a steady cycle, like the seasons, Rabinow wrote down the dates of his various inventions, and found that relatively few ideas occurred during government service, or when he was scrabbling to commercially develop an existing invention. The invention quotient was highest when he was self-employed.

Now he is back, half-time, at the Bureau of Standards, partly because he enjoys lunching with old friends.

''There's no question you invent depending on the incentive, the climate, the encouragement,'' he says. ''People don't invent just because they're inventors.''

The spark that lights an idea comes most often from a problem. Inventors might just as well be called ''solvers'' - people who refuse to put up with life's little glitches.

Charles Purtle, a Worcester, Mass., inventor, is an extreme example. Once, while he was taking a flying lesson, a wayward plane burst through the clouds and barely missed his trainer.

''I thought, there must be a better way of doing things,'' he says. So he is now developing an aircraft-to-aircraft collision avoidance system.

Rabinow, himself, was offended by his wrist watch. To regulate a watch's speed, you have to unscrew the back (which takes special tools) and fiddle with a part the size of a freckle.

''I thought that was stupid,'' says Rabinow. Instead, he decided the watch should speed up when the hands were moved forward, and slow down when set back.

So he whipped up an invention, discovering along the way that a watch's speed depends on its case, the band, the weather, and the weight of your wrist, among other things. (''When the spring swings one way, the whole earth has to go the other direction. A little.'') He also found out that most watches are set fast at the factory, ''because a fast watch feels OK, but a slow watch feels defective.''

Though he had a hard time selling it, the regulator eventually earned him upwards of $25,000 a year. Ironically, it was used in automobile clocks renowned for their shoddiness. ''At one time, I owned three cars with those clocks,'' says Rabinow. ''None of them worked.''

Not being a fan of modern management techniques, Rabinow is not surprised. He wanders down his living room, towards a bust by sculptor Bob Berks that glances out at the suburban Maryland forest.

''The best in most skills is not (even) two to one over the average,'' he says. ''But when it comes to creativity, the best is infinitely better than the average.''

The best inventors not only solve problems - they recognize needs no one else can see. The office copier may be a shrine now, but Chester Carlson had to knock on hundreds of doors before Batelle Labs advanced the money that started Xerox. Everyone else thought the idea was cute, but not necessary - isn't that what carbon paper is for, after all?

Carlson was able to knock off the blinders of what one invention expert calls ''object-centered thinking,'' - the inability to see anything but what already exists. The act of invention, like all creative endeavor, then becomes a trip down a sort of mental cafeteria line, taking a piece of one idea, two slices of another, and ending up with a brand-new concept. Inventors must thus be able to fit together many seemingly disparate pieces of information.

''You got to have a lot of things stored in your mind,'' says Californian inventor Ray W. Hoeppel. ''Not tightly stored. Loose, so they can rattle around.''

So things rattle around a bit, and an idea strikes. Typically, inventors say their inventions come on them suddenly, like a summer storm.

''One of the main places I invent is driving a car,'' says Charlie Purtle. ''You wake up many times with an invention. It wakes you out of a sound sleep.''

Inventors must be curious and persistent. They must be patient, hard-working, and able to think in both abstract and concrete terms. They must be a bit impractical: a friend once asked Benjamin Franklin what good was one of his minor inventions. Franklin, miffed, replied ''What good is a newborn baby?''

But they must also possess the shrewd practicality of the English inventor who produced 50,000 totally silent records. They were snapped up by jukebox owners, who found many customers eager to pay a few pence for guaranteed quiet dining.In short, they must be like every other successful person, only more so. Whether these traits are innate or acquired is debated. S. Pal Asija, a Connecticut patent attorney, travels cross-country exhorting audiences that inventiveness can be taught, claiming ''federal waste is a drop in the bucket compared to our waste of creative talent.''

On the other hand Lawrence Kamm, President of MOBOT Corp., says ''courses in inventing are like courses in growing tall.''

Teachable or not, inventing, like writing, is a solitary occupation that breeds emotional attachment to the product. Franklin's analogy seems apt: many inventors refer to their ideas as ''children.'' They show off patent drawings as if they were baby pictures, and believe their inventions will grow up to be worth a million dollars.

''When you're talking with an inventor,'' says one patent attorney, ''you have to remember he's got more than a biased viewpoint.''

They are proud of their independence, and suspicious of those who meddle in their affairs. One day the 19th century English inventor Michael Faraday was visited by Sir Robert Peel, then Prime Minister. Peel, spying a prototype of Faraday's famous magnetoelectric generator, asked ''of what use is it?'' (A question inventors are always answering.)

Faraday fixed his Prime Minister with a cynical stare and said ''I know not. But I wager some day your government will tax it.''

Invention may be an art. A good idea may be like a poem, and the act of invention may be a thoroughly satisfying thing. But behind Faraday's reply is a common lament: once the inventing is over, things begin to go awry.

Between taxes, timid management, and cracks in the patent system, many inventions never get far from the workshop.

''For every one that makes it,'' says Gerald Udell, former director of the University of Wisconsin Innovation Center, ''there are ten with good technology going down the drain.''

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