Invacare Corp., Elyria, Ohio, acquired Perry Oxygen Systems, Port St. Lucie, Fla., for an undisclosed amount of cash. Perry manufactures liquid oxygen systems and oxygen delivery systems.

The liquid oxygen segment of the $400 million-plus respiratory market is estimated at $50 million.

The new liquid oxygen products will be introduced under the Mobilaire name later this year, following design enhancements. Liquid oxygen is the standard of care for ambulatory patients because portable units can be filled from a home base unit, giving the individual more freedom of movement, according to the company.

The acquisition rounds out Invacare's oxygen system line, according to Kathleen Obert, director of advertising and public relations. Invacare already supplies two of the three oxygen delivery modalities--oxygen concentrators and compressed gas systems.

Invacare has been expanding its Mobilaire respiratory line since last November, when it introduced nebulizer compressors, pediatric flowmeters and other products at the National Home Health Care Exposition.

The Perry acquisition also gives Invacare patent rights to a new pulse dose oxygen delivery technology. Used with liquid oxygen or compressed gas systems, the technology conserves oxygen, reduces costs and extends the length of time between refills, according to Invacare.

The liquid oxygen systems will be sold through Invacare's 80-rep direct sales force, the largest sales force in the home health care industry.