TOKYO (AP) -- Toyota Motor Corp. will boost overtime pay to its assembly line workers for their voluntary efforts to improve production quality, the company said Thursday.

Toyota, Japan's No. 1 automaker, has a sterling reputation for innovative production methods called "kaizen" that rely on ideas from their workers to cut costs and raise on-the-job efficiency.

Japan tends to encourage a workaholic corporate culture because many companies demand extreme loyalty from their workers. Workers' putting in free overtime is so common here a widely recognized phrase describes the practice, "saabisu zangyo," or "service overtime." But public criticism has been rising for free overtime at some companies.

Toyota autoworkers routinely take part in voluntary meetings called "QC Circle," short for "quality control circle," that focus on improving product quality and manufacturing methods.

Staring next month, Toyota will more fully compensate workers for such meetings, which are outside their shift hours, said Toyota spokesman Paul Nolasco.

The Asahi Shimbun, a major Japanese daily, said previous QC overtime pay had been limited to two hours a month.

Nolasco could not confirm the Asahi report. But he did say that Toyota decided that such voluntary meetings were good for "the cultivation of human resources," and the decision to more fully pay overtime followed a review "of the scope of such activities."

Toyota's growth has been so spectacular analysts say it's a matter of time before the manufacturer of the Prius hybrid, Camry sedan and Lexus luxury cars overtakes General Motors Corp. of the U.S. as the world's biggest automaker.

But Toyota's global expansion has also hurt its quality control, resulting in a surge in recalls. Toyota has been revving up efforts in recent years to improve product quality.