US 2900978 A
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Description (OCR text may contain errors)
Aug. 25, 1.959
D. o. A. JoHANNlssoN 2,900,978
sUcTIoN DEVICE Filed Oct. 15, 1954 j 4 V/ A l INI/W75? BY MRQW ATTORNEY United States Patent SUCTION DEVICE Application October 15, 1954, Serial No. 462,578 Claims priority, application Sweden October 23, 1953 4 Claims. (Cl. 12S-276) The present invention refers to a suction device, which is particularly suited for medical applications and which will therefore be described in an embodiment that lends itself to such applications. However, the device according to the present invention may be used in any connection where it is desired to provide during normal conditions a certain suction effect, which is to be materially enhanced if a predetermined change in the pressure conditions takes place.
In the course of diseases causing respiratory paralysis it is often necessary to suck out mucus from the respiratory organs of a patient. For this purpose a suction bottle is usually connected with the patients breathing organs, subpressure being created in the suction bottle and contributing to cleaning out the breathing organs by suction. Under normal conditions a pressure of approximately 300 mm. Hg may suice for this purpose, but it may be of advantage to create at times a stronger sfuction effect in order to remove mucus clots or the like, for which purpose a higher pressure, such as approximately 600 mm. Hg, may be required.
It is therefore an object of the present invention to provide a device which gives under ordinary conditions a reasonably strong suction effect, butrsupplies, upon a predetermined change in the said conditions, a substantially stronger suction effect.
Particularly, it is an object of the invention to provide a device, in which a certain suction eiect is replaced by a substantially stronger suction when there is a resistance to the admission of the sucked gas into the device.
A further object of the invention is to provide a suction device adapted for connection to the respiratory organs of a patient so as to suck out obstructions` in the organs and in which a higher pressure becomes effective if an obstruction does not yield to the normal subpressure created by the device.
The suction device according to the present invention comprises a rst suction means adapted to create a subpressure, a second `suction means adapted to create a substantially greater subpressure and a switching means responsive to predetermined pressure conditions set up by the iirst suction means to cause the second suction means to become operative.
In a favorable embodiment, the suction means may comprise ejector nozzles adapted to create a subpressure upon the application of gas of increased pressure to the nozzles, the outlet of one nozzle being connected to the inlet of the other. For instance, the outlet of the second nozzle forming the second suction means may be connected to the inlet of the first nozzle.
According to a further feature of the invention, the first and second nozzles are arranged in separate chambers, the chambers being connected to separate suction outlets of the device. In a device of the last mentioned type, the switching means may comprise a non-return valve arranged in the irst outlet.
In a particular embodiment, the suction device may be constructed in the form of a plug for insertion into j 2,900,978v Patented Aug. 25, 1959 ICC an aperture, such as a bottle neck, the suction outlets being then arranged to `communicate with the aperture.
The invention will be described in more detail in a preferredembodiment thereof illustrated on the annexed drawing which dagrammatically discloses the device in cross section. This section is taken through the middle of the substantially cylindrical device in such a manner as to pass through the tubular passages provided therein. The embodiment illustrated is constructed as a plug for insertion into the neck of a suction bottle.
In the ligure, 1 designates the aperture formed by the neck of a suction bottle, into which the suction device 2 is adapted to be inserted.` The suction device is supplied with a gas of higher pressure through an inlet aperture 3 thereof, the gas ilowing through the device and leading it through an outlet'aperture 4. On its way between the apertures 3 and 5' the gas ows through an ejector nozzle 5 forming a second suction means and at which a suction is created, so that a subpressure can be obtained in the chamber 6 adjacent the nozzle 5. The gas then Hows on through a frusto conical passageway 7, which also operates as an ejector nozzle and forms a rst suction means of the device, the suction created by this nozzle or channel being however weaker than that at the nozzle 5. This weaker subpressure is obtained in the chamber 9, which surrounds the outlet of passageway 7. The gas ilows onward through a modied frustoconical passageway 8 and up to the outlet aperture 4. The chamber 9 communicates with the interior of the bottle through valve means connecting the chamber with the bottle neck. This suction outlet is formed by a channel 10, which is provided in an exteriorly threaded tubular piece 11 inserted into a lower, threaded portion of the Vchamber 9. The rupper part of the piece 11 is constructed as a valve seat 12, on which a Valve disk 13 rests. The chamber 6 also communicates with the interior of the bottle through a second suction outlet in the form of a channel or passage 14.
The operation of the device is as follows:
The suction bottle is assumed to be provided with an aperture, by means of which it can be connected, for example, with a patients respiratory organs. Gas under increased pressure is supplied at the aperture 3. This creates a subpressure in the chamber 9, which causes a suction effect in the bottle, provided that it is suilicient to lift the disk 13 off the Valve seat. Under normal conditions this suction effect is suicient to remove mucus and the like. A subpressure is set up in the chamber 6 at the same time, which is no greater than that obtained in the chamber 9. This is true because the ejector 5 is proportioned to have a small capacity yet be able to create a large subpressure, the slot formed between the nozzle aperture and the inlet of the passageway being narrow for this purpose. Under normal operating conditions, when substantially unrestricted gas flow through the slot is possible, the narrowness of the slot gives rise to a substantial pressure drop at the slot, and a large subpressure therefore cannot reach the chamber 6. lf the weaker subpressure of chamber 9 proves insufficient, the ejector 5 continues. to create an increasingly larger subpressure and the valve disc 13 remains seated on its valve seat. Itis thus seen that a larger subpressure can now be obtained in the chamber 6 because the decreased gas ow through the slot about the aperture of the nozzle 5 decreases the pressure drop at the slot and enables the subpressure to reach the chamber 6 and the passage 14. The pressure continues to rise to a substantially higher value, such as of the order of 600 mm. Hg, and the improved suction effect in the respiratory tract is readily obtained. After the larger pressure has been operative, a weaker pressure is again sufficient and the pressure in the suction bottle decreases to such a value that the valve disc 13 can be unseated by the subpressure in the chamgas under pressure' connected with said' second suction means, said rst and second suction means commonly including a frusto-conical passageway providing a flow path such that with normal respirationof said patient said valve means is opened to draw mucus from said tract, and, with restricted respiration due to mucusv blockage and buildup of subapressure in said second suction means, said valve means is closed andsaid passage means is rendered operative to draw mucus from saidv track.
2. A suction device according to claim 1 wherein said first gas suction means further includes a modied frusto- V4 t conical passageway, and said second gas suction means includes an ejection nozzle.
3. A `suction device according to claim 2 wherein said first suction means further includes a rst chamber means intermediate said frusto-conical passageway and said modified frusto-conical passageway, said rst chamber means communicating with said valve means.
4. A suction device accordingtoA claim 2 wherein said second suction means further includes a second chamber means intermediate said ejection nozzle and said frustoconical passageway, said' second chamber means communicating with said passage means.
References Cited in the file of this patent UNITED STATES PATENTS 500,677 Stanley July 4, 1893 2,063,665 Edwards Dec. 8, 1936 FOREIGN PATENTS 690,649 Great Britain Apr. 22, 1953