DE2442647B1

DE2442647B1 - Float valve for infusion and transfusion devices

Info

Publication number: DE2442647B1
Application number: DE19742442647
Authority: DE
Inventors: Heinz Fuchs; Ulrich Dr. Med. Kirsch
Original assignee: B Braun Melsungen AG
Current assignee: B Braun Melsungen AG
Priority date: 1974-09-06
Filing date: 1974-09-06
Publication date: 1976-03-04

Description

In den Zeichnungen sind Ausführungsbeispiele gemäß der Erfindung dargestellt, und zwar zeigt F i g. 1 in starker Vergrößerung den Aufbau des Schwimmerventils im Schnitt, F i g. 2 das geschlossene Ventil mit dem geschlossenen Nadelventil im Tropfdorn, F i g. 3 das wieder geöffnete Ventil, F i g. 4 das erneut geschlossene Ventil. In the drawings are exemplary embodiments according to the invention shown, namely shows F i g. 1 shows the structure of the float valve in a large enlargement in section, F i g. 2 the closed valve with the closed needle valve in the Drip pin, F i g. 3 the reopened valve, FIG. 4 that again closed valve.

Eine Ausführungsform des Schwimmerventils besteht aus einem unten offenen kuppelartigen Schwimmkörper 1, der sich wie ein Hut um den nach oben gezogenen offenen Rand des den Flüssigkeitsauslaß bildenden Tropfdorns 2 herum erstreckt, ohne diesen Rand zu berühren, und einem Nadelventil 3, welches mit seinem oberen Teil in der Mitte des Schwimmkörpers 1 befestigt ist und mit der Ventilspitze den konischen Tropfdorn 2 an einer vorbestimmten Stelle verschließt. One embodiment of the float valve consists of a bottom open dome-like floating body 1, which is like a hat around the pulled up extends around the open edge of the drip mandrel 2 forming the liquid outlet, without touching this edge, and a needle valve 3, which with its upper Part is fixed in the middle of the float 1 and the valve tip conical drip mandrel 2 closes at a predetermined point.

Die Verschlußstelle für das Nadelventil 3 im unteren Teil des Tropfdorns 2 ist so ausgewählt, daß der kuppelartige Schwimmkörper 1 den oberen Rand des Tropfdorns 2 nicht berührt.The closure point for the needle valve 3 in the lower part of the drip mandrel 2 is selected so that the dome-like floating body 1 the upper edge of the drip mandrel 2 not touched.

Der Schwimmkörper 1 und das damit verbundene Nadelventil 3 werden durch den Auftrieb in der Flüssigkeit angehoben, und damit wird der Durchgang des Nadelventils im Tropfdorn 2 freigegeben. Der Auftrieb wird dadurch verstärkt, daß sich Luft unter der Höhlung des Schwimmkörpers 1 befindet. Mit Entleerung der Flüssigkeit sinkt das so gebildete Schwimmerventil tiefer, und das im Tropfdorn 2 befindliche Nadelventil 3 schließt den Flüssigkeitsstrom (F i g. 2). The floating body 1 and the needle valve 3 connected to it are is raised by the buoyancy in the liquid, and with it the passage of the The needle valve in the drip mandrel 2 is released. The buoyancy is increased by the fact that there is air under the cavity of the float 1. With emptying of the liquid the float valve formed in this way sinks lower, and that located in the drip mandrel 2 Needle valve 3 closes the flow of liquid (FIG. 2).

Das Lösen des angesaugten Nadelventils erfolgt durch Druckerhöhung im Übertragungsgerät, z. B. durch Zusammendrücken der flexiblen Tropfkammer 6. Die hierbei nach oben unter den Hohlraum 5 des Schwimmkörpers 1 gedrängte Luft füllt den Hohlraum stärker an als zuvor. Sie verdrängt Wasser unter dem Schwimmkörper, was den erwünschten Nebeneffekt einer Auftriebsvermehrung hat (F i g. 3). Nach erneutem Absinken des Flüssigkeitsspiegels wird die vorher unter der Kuppel des Schwimmkörpers 1 vermehrt angesammelte Luft durch die nachdrängende Flüssigkeit aus dem Raum außerhalb des wallartigen Randes des Tropfdorns 2 und noch innerhalb der Höhlung des Schwimmkörpers 1 über den wallartigen Rand 2 hinweg und durch das Nadelventil 3 hindurch von der nachdrängenden Flüssigkeit wieder in die Tropfkammer 6 zurückgeführt (Fig.4). Es ergibt sich also eine Pendelbewegung eines kleinen Quantums an Luft, welches beim Lösen des Nadelventils 3 aus der Tropfkammer 6 verdrängt und durch Flüssigkeit ersetzt und beim erneuten Schließen des Nadelventils kurz vor dem Schließen wieder in die Tropfkammer 6 zurückbefördert wird.The sucked-in needle valve is released by increasing the pressure in the transmission device, e.g. B. by compressing the flexible drip chamber 6. The in this case, air pushed upwards under the cavity 5 of the floating body 1 fills the cavity more than before. It displaces water under the float, which has the desired side effect of an increase in lift (Fig. 3). After again The drop in the liquid level will previously be under the dome of the float 1 Increased accumulated air due to the liquid pushing in from the room outside of the wall-like edge of the drip mandrel 2 and still within the cavity of the Float 1 over the wall-like edge 2 and through the needle valve 3 from the subsequent liquid is fed back into the drip chamber 6 (Fig. 4). It there is thus a pendulum movement of a small amount of air, which is produced by the Releasing the needle valve 3 is displaced from the drip chamber 6 and replaced by liquid and when the needle valve closes again shortly before it closes, back into the Drip chamber 6 is returned.

Dadurch, daß die zwangläufig beim Lösen des Ventils durch den Tropfdorn 2 zurückgetriebene Luft in einer Zwischenkammer aufgefangen wird, aus der sie wieder in die Tropfkammer zurückgelangen kann, und da dieser Vorgang beliebig oft wiederholbar ist, wird der obenerwähnte Nachteil vermieden, daß die Tropfstrekke in der Tropfkammer von Luft völlig entleert und damit zum Erkennen der Geschwindigkeit der Tropfenfolge unbrauchbar wird. The fact that the inevitable when loosening the valve by the drip pin 2 driven back air is collected in an intermediate chamber, from which it is recovered can get back into the drip chamber, and since this process can be repeated as often as required is, the above-mentioned disadvantage that the drip path in the drip chamber is avoided completely emptied of air and thus to recognize the speed of the series of drops becomes unusable.

Schwimmkörper 1 und Nadelventil 3 können in einem Stück gefertigt sein. Float 1 and needle valve 3 can be manufactured in one piece be.

Bei einer anderen Ausführungsform des Schwimmerventils wird auf die Anordnung eines Nadelventils verzichtet. Hierbei ist der Rand des unten offenen Schwimmkörpers 1 rundum als Dichtungslippe gegenüber der oberen Begrenzung 4 der Tropfkammer 6 ausgebildet. Auf dieser Begrenzung 4 liegt der Schwimmkörper 1 mit seinem Rand dicht auf, wenn das Ventil geschlossen ist, ohne daß der Rand des Tropfdorns 2 vom Schwimmkörper berührt wird. In another embodiment of the float valve, the Arrangement of a needle valve dispensed with. Here is the edge of the open at the bottom Floating body 1 all around as a sealing lip against the upper limit 4 of the Drip chamber 6 formed. On this boundary 4, the floating body 1 lies with its edge tightly when the valve is closed, without the edge of the drip mandrel 2 is touched by the float.

In den Zeichnungen sind etwaige zweckmäßige Vorrichtungen zur Begrenzung der Bewegung des Schwimmkörpers nach oben fortgelassen. Der Schwimmkörper wird zweckmäßigerweise aus einem gegenüber der Flüssigkeit inerten Material, z. B. aus einem thermoplatischen Kunststoff, hergestellt, dessen spezifisches Gewicht kleiner als list. In the drawings are any suitable devices for limiting the movement of the float upward is omitted. The float is expedient made of a material inert to the liquid, e.g. B. from a thermoplastic Plastic manufactured with a specific weight less than list.

Claims

Claims: 1. Float valve to shut off in the drip chamber air flowing in from infusion or transfusion devices, g e k e n n z e i c h n e t d u r c h a dome-like floating body (1) open at the bottom, which is with its cavity around the upwardly drawn, wall-like, open edge of the den Liquid outlet forming drip mandrel (2) sets without touching this edge.

2. float valve according to claim 1, characterized in that a Needle valve (3) attached with its upper part in the middle of the float (1) and that the valve tip is close to the drip mandrel (2) at a predetermined point whose narrowing outlet opening closes.

3. float valve according to claim 1, characterized in that the Edge of the floating body (1), which is open at the bottom, is designed as a sealing lip all around is, by means of which it is tight on an upper boundary (4) of the drip chamber (6) rests.

The invention is based on a float valve for shutting off Air flowing into the drip chamber of infusion or transfusion devices.

There is a need for a device that prevents air ingress to prevent in a fluid transfer system, e.g. B. in blood transfer devices, in which the blood to be transferred is accelerated by compressed air is, but also generally when supplying infusion solutions into a transmission device.

The ingress of air into a transmission device would occur initially do not mean any immediate danger to the patient, but it would mean an increased risk Personnel workload because the transmission system is new would have to be filled. The transmitter must be free of air during the infusion otherwise this would get into the patient's circulatory system due to forcing fluid causing an air embolism with dangerous and potentially harmful Consequences is caused. Another need for a device that prevents penetration of air during infusions is prevented by dosing tanks, which are used as feed tanks turned into a common fluid transfer device to a small Subset of the infusion liquid to be determined beforehand during a given Infusion period should not be exceeded.

The essential parts of an infusion system for parenteral Fluid therapy are 1. a drop former in the form of a hollow spike, 2. a Fall section for observing the drops, which contains air, 3. a collecting chamber (Drip chamber) at the bottom of the drop section of the drop, where liquid is entrained by it Can separate air and 4. a fluid-filled hose connected to it with one suitable for connection to a hollow needle or a venous catheter Approach.

As these parts of the transmission device in the order described are necessary for the proper transfer of infusion fluids th, will shut-off devices in the form of a float valve mounted above the same.

If the liquid in the infusion bottle runs out, the will decrease The float of the float valve and closes the liquid inlet to the drip mandrel, whereby the device is locked in a functional state and not through the ingress of air can be rendered inoperable. After bringing one The float valve should open the float valve by floating the float to create a new supply of liquid clear the path of the infusion fluid through the transmission device again. That is usually not the case, however, because the drip chamber and float valve are above of the patient level are attached and one opposite in the area of the float valve the atmosphere negative pressure due to the dependent liquid column in the transmission device is produced. The float valve is thus sucked in. As a rule, the float valve must then be released mechanically, either by lowering the drip chamber briefly below patient level and the resulting return flow of blood into the transmission device or by manual compression of the drip chamber, which is flexibly designed for this purpose is effected.

This backflow of liquid or manual compression the drip chamber have major disadvantages because the drip spike causes a small amount Air from the drip line enters the area of the float valve and hits the float of the valve passes into the space above the liquid to be transferred. The volume of the drip path is reduced by this volume of air. After several times Repeating this process, the drip path is completely emptied of air and thus can no longer be used to detect the speed of the droplets.

In DT-PS 9 58 655 a cylinder valve for gas cylinders, in particular Bottles for liquid gases, described, which is characterized by that in the gas path a device which leaves the gas path free for displaying the through a dip tube defined emptying state of the bottle is switched on. One Embodiment of the display body is plate-shaped, but can not serve as a float of a float valve, as in the plate-shaped display body two openings x are provided for the main gas flow.

The present invention is based on the object of a float valve for infusion or transfusion devices for parenteral fluid therapy to create, through which the disadvantages described above are avoided, especially as regards the escape of air from the drip chamber.

According to the invention, this object was achieved by means of a float valve to shut off any inflowing into the drip chamber of infusion or transfusion devices Air, characterized by a dome-like float open at the bottom, the with its cavity around the wall-like, open edge of the the liquid outlet forming the drip mandrel lays without touching this edge.