Active exhalation valve

1. An active exhalation valve for use with a ventilator to control flow of patient exhaled gases, comprising:

a patient circuit connection port;

a patient connection port;

an exhaled gas port;

a pilot pressure port;

a valve seat; and

a movable poppet including an inner bellows member, an outer bellows member and a bellows poppet face, the pilot pressure port being configured such that an activation pressure applied to the pilot pressure port extends the inner and outer bellows members to move the bellows 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 to the pilot pressure port allows the inner and outer bellows members to move the bellows 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.

2. The exhalation valve of claim 1 , wherein the inner and outer bellows members define an interior bellows chamber therebetween and the pilot pressure port is in fluid communication with the interior bellows chamber.

3. The exhalation valve of claim 2 , wherein the inner bellows member has an inner bellows fluid passageway extending therethrough in fluid communication with the patient circuit connection port and the patient connection port.

4. The exhalation valve of claim 3 , wherein the inner bellows fluid passageway is in continuous fluid communication with the patient circuit connection port and the patient connection port during operation of the exhalation valve, and out of fluid communication with the interior bellows chamber between the inner and outer bellows members.

5. The exhalation valve of claim 1 , wherein the inner bellows member has an inner bellows fluid passageway extending therethrough in continuous fluid communication with the patient circuit connection port and the patient connection port.

6. An active exhalation valve for use with a patient connection and a ventilator having a pressure source usable to control operation of the valve to control flow of patient exhaled gases, comprising:

a patient circuit connection port for fluid communication with the ventilator;

a patient connection port for fluid communication with the patient connection;

an exhaled gas port for fluid communication with air exterior to the valve to remove patient exhaled gases from the valve;

a pilot pressure port for fluid communication with the pressure source;

a valve seat; and

a movable poppet including an inner bellows member, an outer bellows member and a bellows poppet face, the pilot pressure port being configured such that an activation pressure applied by the pressure source to the pilot pressure port extends the inner and outer bellows members to move the bellows poppet face into sealing engagement with the valve seat and restrict flow of patient exhaled gases to the exhaled gas port, and the reduction of the activation pressure applied by the pressure source to the pilot pressure port allows the inner and outer bellows members to move the bellows poppet face away from the valve seat and out of sealing 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.

7. The exhalation valve of claim 6 , wherein the inner and outer bellows members define an interior bellows chamber therebetween and the pilot pressure port is in fluid communication with the interior bellows chamber.

8. The exhalation valve of claim 7 , wherein the inner bellows member has an inner bellows fluid passageway extending therethrough in fluid communication with the patient circuit connection port and the patient connection port.

9. The exhalation valve of claim 8 , wherein the inner bellows fluid passageway is in continuous fluid communication with the patient circuit connection port and the patient connection port during operation of the exhalation valve, and out of fluid communication with the interior bellows chamber between the inner and outer bellows members.

10. The exhalation valve of claim 6 , wherein the inner bellows member has an inner bellows fluid passageway extending therethrough in continuous fluid communication with the patient circuit connection port and the patient connection port.

11. An active exhalation valve for use with a ventilator to control operation of the valve to control flow of patient exhaled gases, comprising:

a patient circuit connection port;

a patient connection port;

an exhaled gas port;

a pilot pressure port;

a valve seat; and

a movable poppet including an inner member, an outer member and

a poppet face, the pilot pressure port being configured such that an activation pressure applied to the pilot pressure port moves the inner and outer members toward the valve seat 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 to the pilot pressure port allows the inner and outer members to move away from the valve seat to move the poppet face 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.

12. The exhalation valve of claim 11 , wherein the inner and outer members define an interior chamber therebetween and the pilot pressure port is in fluid communication with the interior chamber.

13. The exhalation valve of claim 12 , wherein the inner member has an inner member fluid passageway extending therethrough in fluid communication with the patient circuit connection port and the patient connection port.

14. The exhalation valve of claim 13 , wherein the inner member fluid passageway is in continuous fluid communication with the patient circuit connection port and the patient connection port during operation of the exhalation valve, and out of fluid communication with the interior bellows chamber between the inner and outer bellows members.

15. The exhalation valve of claim 11 , wherein the inner member has an inner member fluid passageway extending therethrough in continuous fluid communication with the patient circuit connection port and the patient connection port.