Japanese consumers are not reaping many benefits from their currency's rapid appreciation against the American dollar and their irritation is beginning to slow.

The usually ineffectual consumers' movement is mounting a major campaign for lower prices as a result of the yen's appreciation and their demands already have provoked a rare public quarrel within the government over economic policy.

Virtually every analysis shows that consumers are due a price breaj because of the falling cost of imported goods and materials - bought more cheaply during the yen's rise against the dollar.

But with a few exceptions, business is hanging on to its windfall profits. The Mitsubishi Bank, a pillar of the big business establishment, recently calculated that during an 18 mont period ending last June consumer prices should have fallen about 2 percent solely because of the yen's higher buying power. Instead, they went up nearly 8 percent.

Almost all of the materials used in Japan's manufactures are imported and paid for in dollars and the yen's appreciation against the dollar has made it a buyer's market for importers and big business.

The consumers' uprising is centered now on the indisputably hefty profits rolled up by electric power and gas companies which are being pressured to reduce their rated to homeowners. The government estimates that the companies realized nearly $600 million last fiscal year simply because the dollar costs of imported crude oil and natural gas were less. Consumer organization and Japan's Socialist Party put the profits at much more. Power rates have remained unchanged.

The disparity in such profits and prices has angered consumer organizations and encouraged them to believe they can force prices down by lobbying the government and corporations. One veteran of the movement, Matsuyo Yamamoto, says that pricing issuesare usually murky, with the pros and cons leaving citizens confused and inactive.

"It's more likely to succeed this time because (the issue) is so obvious," she says. "For the government to deny the movement this time is rather hard. "

In the past, Japan's consumer movement has rarely been effective in national campaigns. In 1971, boycotts brought down the prices of color television sets and four years ago a campaign forced makers of tofu, a food delicacy made of soybeans, to stop using a preservative suspected of causing cancer. But the movement is not taken seriously by most politicians and it lacks a forceful leader.

"We have no Ralph Nader," observed Yamamoto.

One reason is the Japanese traditionaof accepting authority and of not challenging established institutions, said Akika Shoda, professor of social and anti-trust law at Keio University. Japan has no experience in "citizen revolutions" and people are "not as likely to confront the corporation as are people in the United States and Europe," he added. Nevertheless, Shoda thinks the movement is gaining strength gradually through campaigns against overpricing unsafe chemicals, and false labeling.

The campaign against power and gas companies has become a major test of consumers' political clout. The National Liaison committee of consumers, an alliance of 19 organizations claiming 20 million members, has mapped out an ambitious fall offensive that calls fro extensive lobbying in parliament, demonstrations, and a mass rally in Tokyo, all geared to bringing down utility rates.

To Shoji Onno, secretary general of the liaison committee, the utility rate challenge is only a first step. If successful, it will be expanded to newtargets - food prices and other items in the household budget. Chicken and pork prices should come down because farm feed is purchased abroad with cheap dollars, he contended. So should the cost of coffee, which has already depped a bit under buyers' perssures, he added.

Retail prices of some items, such as film, cars and refrigerators, already have come down as the yen's appreciation took effect. But the Mitsubishi Bank report shows there has been an over*all rise in consumer prices and notes that wholesale prices have only dropped about 2 percent when they should have come down 5.4 percent. Mitsubishi found many cases where significant price decreases were not warranted, party because companies did not import goods during the period of the yen's rise and partly because many are suffering from a prolonged recession caused by the oil price shocks.

So far, the government of Prime Minisyer Takeo Fukuda has resisted the utility rate challenge. The powerful Minsitry of International Trade and Industry insists that the utility corporations' profits should be ploughed into capital investments for new power plants and generators as part of the government's promise to stimulate the economy this fall.

"If the profits are returned to consumers it would mean a fragmentation of those profits and so its economic meaning would be very small," says the ministry's top energy official, Naohiro Amaya. "It would not have the effect of stimulating the economy." The ministry says reduced utility rates would mean only a savings of 100 yen (About 50 cents) a month to the average household. Consumer organizations insist th rate cuts should amount to far greater savings.

Despite the Ministry's insistenece, consumer pressure has oppened up unusual fissures in Fukuda's government and the business community. Fukdua's main political rival, Masayoshi Ohira, secretary general of the Liberal Democratic Party, broke ranks two weeks ago the suggest that benefits of the yen's appreciation should be passed on to consumers. So did Telichiro Morinaga, governor of the Bank of Japan, and Justice Minister Mitsuo Setoyama.

Their defections apparently shocked the Fukuda Government. The day after Ohira's statement, chief Cabinet secretary Shntaro Abe said there would be a government study and some of the profits might be passed on the consumers if the yen continues to rise.

The utility companies, other big businesses and the influential Feberation of Economic Organizations have insisted there should be no rate reductions. But the Japan Chamber of Commerce and Industry, which generally represents small business firms demaged by the yen's appreciation, came out forrate cuts, leaving the corporate community divided.