Once upon a time there was a Japanese woman who invented a really good doughnut-making machine.
She obtained a patent, but almost immediately afterward someone copied the idea. Lacking legal experience, the woman did not know how to stop the emergence of a rival product and ended up making no money at all from her invention.
''She became depressed and at times seemed on the verge of suicide,'' recalls Reiko Matsutoya, in telling this particular story. The woman did not commit suicide. But her example spurred others to self-protection, and provided part of the original impetus for the vigorous and wide-ranging activities of the Japan Women Inventors Association.
The association's vice-president, Mrs. Matsutoya, a sprightly, acid-tongued lady in her 70s, says women had to band together to discount the idea that only men were good inventors.
''Before World War II, you know, there were a number of good women inventors. But they didn't know a thing about applying for patents and so applications were made for them by men. The inventions, therefore, were registered in men's names.
''According to official records, for example, corsets and weaving machines were invented in Japan by men. Not a bit of it. . . . The actual creative work was done by women.''
Before the war, women were part of the official male-dominated inventors group. After the war, when it became obvious they would continue to play a second-class role, 30 women struck out on their own, with no money and very little knowledge of what to do with their good ideas.
The experience of the doughnut machine inventor, however, confirmed the belief of the founding group that there was no substitute for knowledge and numbers.
One of the few with any experience of turning ideas into cash was Mrs. Matsutoya. One of her best inventions -- still going strong today -- sprang from the bundles of used clothes that the United States sent to a destitute Japan in the immediate postwar years. Her idea was to dye threadbare old socks and transform them into beautiful artificial flowers and corsages.
The early years were a struggle for the female pioneers -- although a sympathetic government did help them polish up their patent application skills.
Most members are housewives, whose inventing activities are necessarily sporadic. In any one year, probably about 1,000 women are active. All told, some 10,000 have been involved in the past 30 years.
Sometimes, a woman approaches the association with a product already developed. It offers her help in applying for a patent, possibly suggestions for making improvements, and the tricks of the trade learned by veteran members who have become rich from a string of successful inventions.
On other occasions, a woman may merely have a good idea for a new product or improvement of an existing one. What she wants to know is whether someone else already has had the same idea, and if it's worth proceeding with.
Some successful women let large companies take over their ideas, merely relying on royalty payments. Others prefer to go it alone, setting up their own companies.
''Most housewives don't have a business background,'' says Mrs. Matsutoya, ''so we normally try and deter them from forming their own companies, which can often lead to heartbreak. But if they decide to go this route, other women rally around, often acting as sales agents.''
One purpose of the association, she says, is to ''prevent these women from becoming inventing maniacs. We try to instill a sense of proportion that while it's good a woman uses her brain, she shouldn't neglect home and family.''
Many women become so successful that their husbands give up careers to join the new business.
At present, the association's members rarely come up with new concepts. Rather, they improve existing products, especially those within their own practical household experience.
From the grumbling stage of ''why doesn't someone invent a better floor mop, '' they move toward producing the necessary improvement themselves.
The government has designated April 18 as Inventor's Day and each year the women's association holds an exhibition of its members' latest creations. Mrs. Matsutoya believes this may be her group's most important contribution to improving women's lives.
''Many women come to see the exhibition,'' she says. ''When they see the products on display, they often say in a surprised tone: 'Why, I had exactly the same idea, but did nothing about it. So that means I can invent things too.' So these women gain self-confidence.''
Inventing, she says, can give a woman a new sense of worth. It is intellectually stimulating -- and ''it can really keeps you young.''