Federal Reserve Chairman Ben Bernanke. (Jeffrey MacMillan/Capital Business)

In what might be his final years as chairman of the Federal Reserve, Ben S. Bernanke is transforming the U.S. central bank, seeking to shed its reclusive habits and make it a constant presence in bolstering the economy.

The new approach would make the Fed’s policies more responsive to the needs of the economy — and likely more forceful, because what the Fed is planning to do would be much clearer. A key feature of the strategy could be producing a set of scenarios for when and how the Fed would intervene, which would mark a dramatic shift for an organization that throughout its history has been famously opaque.

Bernanke has already pushed the Fed far along this path. The central bank this month pledged to stimulate the economy until it no longer needs the help, an unprecedented promise to intervene for years. That’s a big change from the Fed’s usual role as a curb on inflation and buffer against financial crises.

“It’s a re-imagining of Fed policy,” said John E. Silvia, chief economist at Wells Fargo. “It’s a much more explicit commitment than people had thought about in the past. It’s a much stronger commitment to focus on unemployment.”

As the Fed becomes more forceful and interventionist, it creates new risks for itself. Bernanke’s actions have provoked tough criticism from conservatives in Congress, who have proposed more closely regulating what the Fed can do. The Fed takes pride in its independence, but becoming more interventionist may plunge it deeper into the political maelstrom.

With his new approach, Bernanke is searching for an elixir for a problem that has plagued the Fed’s efforts to help the economy. Each time Fed officials have acted during the recent downturn, the effort has been limited in scope. When the Fed’s program has ended, invariably it has not accomplished enough.

Now, the Fed is saying that it plans to continue stimulating the economy well after the recovery gets strong. The virtually unlimited nature of the pledge means that financial markets will know that the Fed will probably step in whenever growth weakens — and that may have powerful calming effects on the economy.

“Stating that we expect to keep a highly [stimulative] stance for policy for a considerable time after the recovery strengthens is an important reassurance to households and businesses,” Charles Evans, president of the Federal Reserve Bank of Chicago, said in a speech last week.

Bernanke is also studying the idea of declaring that the Fed will boost the economy until unemployment reaches a specific target or until inflation takes off. Some Fed officials have suggested that the central bank keep on stimulating until unemployment reaches 7 percent or inflation rises to 3 percent; others have proposed Fed action until unemployment reaches 5.5 percent or inflation rises to 2.25 percent.

The Fed’s legal mandate is to minimize unemployment and keep prices stable; the Fed has set a long-term inflation target of 2 percent per year.

While many top Fed officials agree with a far more detailed approach, the Fed has not reached final agreement on which new steps to take. But any measures would build on the Fed’s announcement this month that it will launch a series of open-ended policies to spur job creation. The stimulus comes in the form of a plan to hold interest rates near zero at least through mid-2015 and to buy $143 billion in mortgage bonds through the end of the year, and then continue the purchases as long as necessary.

“They’ve basically signaled that this time is going to be different,” said Michelle Girard, senior U.S. economist at RBS. “They’re going to keep the foot on the gas until the economy responds.”

The new strategy still carries a number of risks. The most significant is that the Fed’s efforts heat up economic growth in a way that unleashes inflation, which would eat away at middle-class incomes.

“A commitment to provide stimulus beyond the point at which the recovery strengthens and growth increases implies too great a willingness to tolerate higher inflation,” Jeffrey M. Lacker, the president of the Federal Reserve Bank of Richmond, said in a speech last week.

Lacker was the only one of the 12 voting members of the Fed’s governing committee to dissent from this month’s decision.

Despite that dissent, Bernanke’s efforts to remake the Fed dovetails with his efforts to forge a greater consensus among members of the Federal Open Markets Committee.

Bernanke believes that the consensus is especially critical now because the Fed’s promises extend beyond the chairman’s term, which ends in early 2014. Many economists expect Bernanke to step down then after eight grueling years.

Together, the push for the Fed to take a more aggressive stance against unemployment and make decisions by consensus fulfills two longtime goals of Bernanke, one of the preeminent Fed scholars before becoming chairman.

As a college professor, he strongly advocated that central banks not stand idly by during times of high unemployment and argued that more deliberation at central banks can increase the legitimacy and impact of their actions.

But the search for consensus may have also delayed the Fed’s actions.

By late July, for instance, Bernanke thought the jobs market was weak, and he was ready to launch a major intervention. At the Fed’s meeting July 31 and Aug. 1, Bernanke circulated open-ended language the Fed would later release.

But some of Bernanke’s colleagues were not convinced that any new measures would be particularly effective and wondered whether it would be better to save those weapons for a crisis, such as what might happen if Greece leaves the euro zone.

Since the Fed had announced a stimulus in June, Bernanke was willing to wait to do another major stimulus. Instead, the Fed issued statements suggesting that action would be on its way if the economy did not improve.

Over six weeks of lobbying, Bernanke convinced the other committee members that the labor market was extremely weak and that additional action could help. He told them he expected new stimulus to help create 500,000 jobs.

In a bit of cunning, he argued that the open-ended nature of the commitment — which most economists view as highly stimulative — would allow the Fed to pull back if the economy takes off.

The chairman’s pursuit of consensus has had costs, according to many economists. These economists, some of whom are close to Bernanke, have excoriated his record as failing to respond vigorously enough to a national crisis of 12.5 million people without jobs.

While left-leaning economists have pressed Bernanke to do more, he has also felt heat from the right to stop intervening in the markets.

Republicans have accused Bernanke of subsidizing the nation’s borrowing binge by buying more than a trillion dollars in U.S. government debt since 2008 — a position he has rejected.