Sequential compression device

Claim 1

In a pressure generating device for applying compressive forces against a patient's limb through means of a flexible sleeve connectable therewith and enclosing the limb, said sleeve having a plurality of closed pressure chambers and a ventilation chamber with a plurality of openings facing the limb when enclosed therein, the improvement comprising: a source of pressurizable fluid; a plurality of first valve members connected between the source and the plurality of pressure chambers, respectively; a second valve member connected between the source and the ventilation chamber; and means connected with the valve members for electronically controlling them to periodically apply pressure to said chambers said electronic controlling means including means for successively generating a plurality of first electrical actuation signals for actuating said plurality of first valve members to successively pressurize said plurality of pressure chambers, respectively, means for substantially simultaneously terminating said plurality of first electrical actuation signals to substantially simultaneously deactuate all of said plurality of first valve members, means for generating a second actuation signal for actuating said second valve member to couple said source of pressurizable fluid to the ventilation chamber substantially concurrently with termination of all of said first actuation signals, and means for terminating said second actuation signal for deactuating said second valve member substantially concurrently with the next actuation of the first pressure chamber.