US Patent 10105509 Active exhalation valve

An active exhalation valve for use with a ventilator to control flow of patient exhaled gases. The valve includes a patient circuit connection port, a patient connection port, an exhaled gas port, a pilot pressure port, and a valve seat. The valve further has a movable poppet with inner and outer bellows members and a bellows poppet face. An activation pressure applied to the pilot pressure port extends the bellows members to move the poppet face into engagement with the valve seat and restrict flow of patient exhaled gases to the exhaled gas port, and the reduction of the activation pressure allows the bellows members to move the poppet face away from the valve seat and out of engagement with the valve seat to permit flow of patient exhaled gases to the exhaled gas port, thereby controlling the flow of patient exhaled gases from the valve.