Controllable expiration valve arrangement for a ventilating apparatus

[54] CONTROLLABLE EXPIRATION VALVE ARRANGEMENT FOR A VENTILATING APPARATUS

[75] Inventors: Helge Frank, Liibeck; Eric Hecker, Stockelsdorf; Reinhard Eifrig, Liibeck; Dieter Weismann, Gross Gronau; Peter Gebhardt, Stockelsdorf, al] of Fed. Rep. of Germany

[73] Assignee: Dragerwerk Aktiengesellschaft, Liibeck

[21] Appl. No.: 374,066

[22] Filed: Jun. 30, 1989

[30] Foreign Application Priority Data

Jul. 7, 1988 [DE] Fed. Rep. of Germany 3822950

[51] Int. CI.5 A62B 9/02; A61M 16/00

[52] U.S. CI 128/205.24; 128/204.26;

128/204.18

[58] Field of Search 128/205.24, 205.19,

128/204.26, 204.18

[56] References Cited

U.S. PATENT DOCUMENTS

3,385,295 5/1968 Beasley 128/205.24

3,486,502 12/1969 Wilson 128/205.24

3,905,362 9/1975 Eyrick et al 128/205.19

4,190,045 2/1980 Bartels 128/205.24

4,227,523 10/1980 Warnow et al 128/205.24

4,454,893 10/1984 Orchard 128/205.24

4,813,409 3/1989 Ismach 128/205.24

FOREIGN PATENT DOCUMENTS

2525359 12/1975 Fed. Rep. of Germany .

2573658 5/1986 France 128/205.24

Primary Examiner—Edgar S. Burr
Assistant Examiner—Kimberly L. Asher
Attorney, Agent, or Firm—Walter Ottesen

[57] ABSTRACT

The invention is directed to a controllable expiration valve having a control valve for generating an end expiratory overpressure with the control valve providing the changeable control pressure. The expiration valve is improved so that it is made controllable for compensating dynamic end expiratory overpressure. For this purpose, the membrane chamber of the expiration valve as well as the outflow chamber of the control valve are connected with a device for generating an underpressure.

5 Claims, 3 Drawing Sheets
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