Plymouth-based Select Comfort is alleging in a federal lawsuit that its patented Sleep Number bed concept is being ripped off by the world's largest bedding provider.

Select Comfort, maker of the bed equipped with adjustable and "uniquely designed air chambers," said in the suit filed this week that Tempur Sealy International has been infringing on its patent since last year when Sealy began selling its Tempur-Choice model.

Sealy's version "also allows users to adjust the firmness of their bed by inflating deflating the air chambers"and is constructed in a way that steps on Select Comfort's patent, the Minnesota company claimed in its suit.

Select Comfort, with 423 stores nationwide, is seeking unspecified damages, with interest, as well as reimbursement for all legal expenses.

Sealy's website lists Select Comfort as one of its top three competitors.

Sealy spokesman Mark Rupe said Thursday that the company does not comment on pending litigation.

Paul Walsh • 612-673-4482