Expiration valve control arrangement for a ventilating apparatus

• US 5,065,746 A
• Filed: 06/30/1989
• Issued: 11/19/1991
• Est. Priority Date: 07/07/1988
• Status: Expired due to Fees

• Current Assignee: Dragerwerk AG Moislinger Allee 53/55 Federal Republic of Germany
• Original Assignee: Dragerwerk AG
• Inventors: Steen, Hans-Wilhelm
• Primary Examiner(s): Burr, Edgar S.
• Assistant Examiner(s): Asher, Kimberly L.
• Application Number:
  US07/374,065
• Time in Patent Office: 872 Days
• Field of Search: 128/205.19, 128/205.24, 128/204.26, 128/204.18
• US Class Current: 128/205.24
• CPC Class Codes: A61M 16/20 Valves specially adapted to medical respiratory devices
• CPC Class Codes: A61M 16/205 used for exhalation control
• CPC Class Codes: A61M 16/206 Capsule valves, e.g. mushroom, membrane valves
• CPC Class Codes: A61M 16/207 Membrane valves with pneumatic amplification stage, i.e. having master and slave membranes

Abstract

The invention is directed to an expiration valve control arrangement for a ventilating apparatus. The control arrangement includes a control valve for generating a control pressure in the control chamber of an expiration valve. The control valve includes a connecting passage supplied from a control gas source via a control gas line. The connecting passage opens into an outflow chamber of the control valve and the outflow chamber has an outlet to the ambient. The control valve is configured so that the dynamic end expiratory overpressure can be compensated. For this purpose, the connection passage of the control valve includes a throttle generating an underpressure and a pressure line extends from this throttle and opens into the control chamber of the expiration valve. A closure force is applied to a closure element at the outlet of the connection passage. The closure element coacts with the throttle with the underpressure being adjusted by adjusting the closure force on the closure element. The valve chamber of the expiration valve is connected to a device generating an underpressure.

Claims

1. An expiration valve control arrangement for a ventilating apparatus having an expiration branch line, said expiration branch line producing dynamic flow resistance as the exhaled breathing gas flows therethrough, said dynamic flow resistance producing dynamic positive end expiratory pressure in the expiration branch line, the arrangement comprising:

an expiration valve having an expiration valve housing and membrane valve means for partitioning said housing into a control chamber and a valve chamber;

an inlet for admitting exhaled breathing gas into said valve chamber;

said membrane valve means being movable so as to close said inlet during inspiration and open said inlet during expiration so as to cause said inlet to communicate with said valve chamber;

means for compensating for said dynamic positive end expiratory pressure comprising;

control valve for generating a control pressure for maintaining a desired end expiratory pressure during expiration in said control chamber of said expiration valve, said control valve including a control valve housing and a plate membrane for partitioning said control valve housing into first and second chambers;

control gas supply means for supplying a control gas under pressure;

feed means for conducting said control gas into said control valve;

said control valve including valve seat means disposed in said first chamber and communicating with said feed means;

said plate membrane being mounted in said control valve housing for coacting with said valve seat means for opening and closing said valve seat means to said first chamber;

said feed means including throttle means disposed between said supply means and said valve seat means for throttling the flow of said control gas

a conduit connecting said throttle means to said control chamber of said expiration valve for transmitting said control gas to said control chamber;

underpressure means for generating an underpressure in said valve chamber of said expiration valve corresponding to said dynamic positive end expiratory pressure; and

,

said control valve further including force applying means for applying a first force to said plate membrane during said inspiration for closing said valve seat means to said first chamber thereby causing the control gas flowing from said throttle means to produce an overpressure in said control chamber causing said membrane valve means of said expiration valve to close and for applying a second force to said control membrane during said expiration for opening said valve seat means to said first chamber, and said force applying means coating with said throttle means to adjust said desired end expiratory pressure in said control chamber causing said membrane valve means to open and permit exhalation, said second force being less than said first force and being adjustable to set said desired end expiratory pressure in said control chamber to compensate for said dynamic positive end expiratory pressure in the expiration branch line.

2. The expiration valve control arrangement of claim 1, said underpressure means comprising a suction pump connected to said first and second chambers and said valve chamber.

3. The expiration valve control arrangement of claim 1, said feed means defining a passage and said throttle means being a constriction formed in said passage.

4. The expiration valve control arrangement of claim 3, said passage having a first cross section and said constriction being formed by causing the cross section of said passage to be reduced to a preselected second cross section.

5. An expiration valve control arrangement for a ventilating apparatus, the arrangement comprising:

an expiration valve having an expiration valve housing and membrane valve means for partitioning said housing into a control chamber and a valve chamber;

said membrane valve means being movable so as to close during inspiration and open during expiration;

a control valve for generating a control pressure in said control chamber of said expiration valve, said control valve including a control valve housing and closure means for partitioning said control valve housing into first and second chambers;

control gas supply means for supplying a control gas under pressure;

feed means for conducting said control gas into said control valve;

said closure means including valve seat means disposed in said first chamber and communicating with said feed means; and

, a closure member for coacting with said valve seat means for opening and closing said valve seat means to said first chamber;

said feed means including throttle means disposed between said supply means and said valve seat means for throttling the flow of said control gas;

a conduit for connecting said throttle means to said control chamber of said expiration valve;

underpressure means for generating an underpressure in said valve chamber of said expiration valve;

said closure means including force applying means for applying a first force to said closure member during said inspiration for closing said valve seat means to said first chamber thereby causing the control gas flowing from said throttle means to produce an overpressure in said control chamber causing said membrane valve means to close and for applying a second force to said closure member during said expiration for opening said valve seat means to said first chamber and to coact with said throttle means to produce an underpressure in said control chamber causing said membrane valve means to open, said second force being less than said first force and being adjustable to set said underpressure to a predetermined value;

said closure member being a plate membrane partitioning said first chamber from said second chamber;

said force applying means being an actuator for actuating said plate membrane; and

,

said first chamber being an outflow chamber having an outlet communicating with the ambient and said second chamber being a control chamber likewise having an outlet communicating with the ambient.

6. The expiration valve control arrangement of claim 5, said actuator comprising a plunger-coil arrangement having a movable push rod connected to said plate membrane;

and, resilient biasing means for biasing said plate membrane against said valve seat means.

7. The expiration valve control arrangement of claim 6, said resilient biasing means being a pressure spring interposed between said push rod and said control valve housing.

8. An expiration valve control arrangement for a ventilating apparatus, the arrangement comprising:

an expiration valve having an expiration valve housing and membrane valve means for partitioning said housing into a control chamber and a valve chamber;

said membrane valve means being movable so as to close during inspiration and open during expiration;

a control valve for generating a control pressure in said control chamber of said expiration valve, said control valve including a control valve housing and closure means for partitioning said control valve housing into first and second chambers;

first control gas supply means for supplying a first control gas at a first control pressure;

second control gas supply means for supplying a second control gas at a second control pressure;

feed means for conducting said second control gas into said control valve;

said closure means including valve seat means disposed in said first chamber and communicating with said feed means; and

, a closure member for coacting with said valve seat means for opening and closing said valve seat means to said first chamber;

said feed means including throttle means disposed between said supply means and said valve seat means for throttling the flow of said second control gas;

a conduit for conducting said second control gas away from said throttle means;

switchover means movable into a first switching position for connecting said first control gas supply means to said control chamber of said expiration valve means and then movable out of said first switching position and into a second switching position for connecting said conduit to said control chamber of said expiration valve during expiration;

underpressure means for generating an underpressure in said valve chamber of said expiration valve;

said closure means including force applying means for applying a force to said closure member acting in the closure direction during said expiration for coacting with said throttle means to produce an underpressure in said control chamber causing said membrane valve means to open; and

,

means for adjusting said force to set said underpressure to a predetermined value.

9. An expiration valve control arrangement for a ventilating apparatus, the arrangement comprising:

an expiration valve having an expiration valve housing and membrane valve means for partitioning said housing into a control chamber and a valve chamber;

an inlet for admitting breathing gas into said valve chamber;

said membrane valve means being movable so as to close said inlet during inspiration and open said inlet during expiration so as to cause said inlet to communicate with said valve chamber;

a control valve for generating a control pressure for maintaining a desired end expiratory pressure during expiration in said control chamber of said expiration valve, said control valve including a control valve housing and closure means for partitioning said control valve housing into first and second chambers;

control gas supply means for supplying a control gas under pressure;

feed means for conducting said control gas into said control valve;

said closure means including valve seat means disposed in said first chamber and communicating with said feed means; and

, a closure member for coacting with said valve seat means for opening and closing said valve seat means to said first chamber;

said feed means including throttle means disposed between said supply means and said valve seat means for throttling the flow of said control gas;

a conduit for connecting said throttle means to said control chamber of said expiration valve;

underpressure means for generating an underpressure in said valve chamber of said expiration valve;

said closure means including force applying means for applying a first force to said closure member during said inspiration for closing said valve seat means to said first chamber thereby causing the control gas flowing from said throttle means to produce an overpressure in said control chamber causing said membrane valve means to close and for applying a second force to said closure member during said expiration for opening said valve seat means to said first chamber and to coact with said throttle means to produce an underpressure in said control chamber causing said membrane valve means to open, said second force being less than said first force and being adjustable to set said underpressure to a predetermined value; and

,

said first chamber being an outflow chamber having an outlet communicating with the ambient and said second chamber being a control chamber likewise having an outlet communicating with the ambient.

10. An expiration valve control arrangement for a ventilating apparatus, the arrangement comprising:

an expiration valve having an expiration valve housing and membrane valve means for partitioning said housing into a control chamber and a valve chamber;

said membrane valve means being movable so as to close during inspiration and open during expiration;

a control valve for generating a control pressure in said control chamber of said expiration valve, said control valve including a control valve housing and closure means for partitioning said control valve housing into first and second chambers;

control gas supply means for supplying a control gas under pressure;

feed means for conducting said control gas into said control valve;

said closure means including valve seat means disposed in said first chamber and communicating with said feed means; and

, a closure member separate from said throttle means for coacting with said valve seat means for opening and closing said valve seat means to said first chamber;

said feed means including throttle means disposed between said supply means and said valve seat means for throttling he flow of said control gas;

a conduit for connecting said throttle means to said control chamber of said expiration valve;

underpressure means for generating an underpressure in said valve chamber of said expiration valve;

said closure means including force applying means for applying a first force to said closure member during said inspiration for closing said valve seat means to said first chamber thereby causing the control gas flowing from said throttle means to produce an overpressure in said control chamber causing said membrane valve means to close and for applying a second force to said closure member during said expiration for opening said valve seat means to said first chamber and to coact with said throttle means to produce an underpressure in said control chamber causing said membrane valve means to open, said second force being less than said first force and being adjustable to set said underpressure to a predetermined value;

said closure member being a plate membrane partitioning said first chamber from said second chamber; and

,

said force applying means being an actuator for actuating said plate membrane.

11. The expiration valve control arrangement of claim 10, said first chamber being an outflow chamber having an outlet communicating with the ambient and said second chamber being a control chamber likewise having an outlet communicating with the ambient.