DE1498947C

DE1498947C - Device for filling and emptying a liquid cuvette

Info

Publication number: DE1498947C
Authority: DE
Inventors: Derek David Cambridge Shrewsbury (Großbritannien)
Original assignee: Pye Ltd
Current assignee: Pye Electronic Products Ltd
Publication date: 1972-10-05

Description

den drei Rohre 1, 2 und 3 hindurchgehen. Die Rohre 1 und 2 reichen bis zu einem Niveau L der Küvette C, das der normalen Füllhöhe entspricht. Das Rohr 3 geht nahezu bis zum Boden der Küvette und dient zum Entleeren. Die Rohre 1, 2 und 3 sind mit dünnen Schläuchen la, 2ß und 3a verbunden. Am Stopfen A befestigte Schirme S dienen zur Lenkung der Flüssigkeitsbewegung während des Füll- und Entleervorganges. Die Schläuche 2 a und 3 a führen zu einem Ventil D, dessen Betätigungshebel H bei Hl schwenkbar ist und die Absperrorgane D1 und D 2 gegen die Kraft von Federn D 3 und D 4 öffnen kann. Über die Absperrorgane D1 und D 2 läßt sich die Verbindung zwischen den Schläuchen 2 a und 3 a und einer Saugleitung E herstellen. Der Schlauch la ist am Hebel H befestigt, wobei sein Ende nach unten reicht.go through the three tubes 1, 2 and 3. The tubes 1 and 2 extend up to a level L of the cuvette C, which corresponds to the normal filling level. The tube 3 extends almost to the bottom of the cuvette and is used for emptying. The tubes 1, 2 and 3 are connected with thin hoses 1a, 2ß and 3a. Umbrellas S attached to the plug A serve to direct the movement of the liquid during the filling and emptying process. The hoses 2 a and 3 a lead to a valve D, the operation lever H is pivotable at Hl and can open the valves D 1 and D 2 against the force of springs D 3 and D. 4 The connection between the hoses 2 a and 3 a and a suction line E can be established via the shut-off devices D 1 and D 2. The hose la is attached to the lever H with its end extending downwards.

Die Anordnung arbeitet folgendermaßen: Die Küvette C sei zunächst leer. Es wird nun eine Flasche B, die eine Probe der zu untersuchenden Flüssigkeit enthält, unter den Hebel H gehalten, so daß der Schlauch φ Ια in die Flasche hineinreicht. Hebt man die Flasche in dieser Stellung etwas an, so drückt sie den Hebel nach oben, wodurch der Schlauch 2 a mit dem Saugrohr E verbunden wird. Dadurch wird die Flüssigkeit aus der Flasche B durch den Schlauch la in die Küvette C gesaugt, bis das Niveau L erreicht ist. Weitere überschüssige Flüssigkeit, die in die Küvette eintritt, wird durch den Schlauch 2 α abgezogen. Dann wird die Flasche B weggenommen, wodurch der Hebel H seine mittlere Stellung einnimmt, wobei beide AbsperrorganeD1 und Ό2 geschlossen sind, so daß das Saugrohr E von den Schläuchen 2 a und 3 a abgesperrt ist. Nach Durchführung der Messungen (z. B. bei einem Spektrophotometer) kann die Küvette geleert werden, indem der Hebel H etwas nach unten gedrückt wird, wodurch der Schlauch 3 α mit dem Saugrohr E verbunden wird.The arrangement works as follows: The cuvette C is initially empty. A bottle B, which contains a sample of the liquid to be examined, is now held under the lever H so that the tube φ Ια extends into the bottle. If you lift the bottle a little in this position, it pushes the lever upwards, whereby the hose 2a is connected to the suction tube E. As a result, the liquid is sucked from the bottle B through the hose la into the cuvette C until the level L is reached. Further excess liquid that enters the cuvette is drawn off through the tube 2 α. Then the bottle B is removed, whereby the lever H assumes its middle position, both shut-off devices D 1 and Ό2 are closed, so that the suction tube E is shut off from the hoses 2a and 3a. After the measurements have been carried out (e.g. in the case of a spectrophotometer), the cuvette can be emptied by pressing the lever H slightly downwards, whereby the hose 3 α is connected to the suction tube E.

Um zu verhindern, daß zurückbleibende Tröpfchen im Rohr 1 über die Innenwände der Küvette verspritzt werden, ist der Schirm S vorgesehen, der alle Tröpfchen zum Boden der Küvette leitet. Von dort können sie durch Sog in das Rohr 3 eintreten. Der Schirm S dient auch zur Verhinderung des Auftretens von Luftblasen in der Flüssigkeit während des Füllvorgangs. Die Luftblasen könnten nämlich so zurückbleiben, daß sie teilweise in den Lichtstrahl geraten und dadurch zu falschen Ergebnissen führen würden.In order to prevent droplets remaining in the tube 1 from being splashed over the inner walls of the cuvette, the screen S is provided, which guides all the droplets to the bottom of the cuvette. From there they can enter the pipe 3 by suction. The screen S also serves to prevent air bubbles from appearing in the liquid during the filling process. The air bubbles could remain in such a way that they would partially get into the light beam and thus lead to incorrect results.

Eine andere Möglichkeit zur Verhinderung der Bildung von Luftblasen besteht darin, daß das Rohr 1 in der Küvette so gebogen wird, daß der eintretende Flüssigkeitsstrom niemals auf die Oberfläche der bereits in der Küvette befindlichen Flüssigkeit auftreffen kann. Beispielsweise kann das Ende des Rohres 1 so gebogen sein, daß es auf eine Seitenwand der Küvette gerichtet ist.Another way of preventing the formation of air bubbles is that the pipe 1 is bent in the cuvette so that the incoming liquid stream never hits the surface of the already liquid in the cuvette can hit. For example, the end of the tube 1 can be so be bent so that it is directed towards a side wall of the cuvette.

Die Küvette C ist breiter als sonst bei derartigen Instrumenten üblich und der Stopfen A mit den Rohren 1, 2 und 3 befindet sich an einer Seite des Behälters, so daß bei der optischen Untersuchung der durchtretende Lichtstrahl von den Rohren nicht behindert wird.The cuvette C is wider than usual with such instruments and the stopper A with the tubes 1, 2 and 3 is on one side of the container so that the tubes do not obstruct the light beam during the optical examination.

Beim normalen Meßvorgang muß die Empfindlichkeit des Instruments so eingestellt werden, daß eine Durchlässigkeit von 100% definiert ist. Diese Einstellung erfordert die Einführung eines Bezugskörpers in den Strahlengang an Stelle des zu prüfenden Gegenstandes. Dies ist bei der erfindungsgemäßen Anordnung leicht möglich, da die Schläuche la, 2a und 3a beispielsweise aus Polyäthylen oder einem ähnlichen biegsamen Werkstoff bestehen, so daß die Küvette C leicht herausgenommen werden kann. Statt dessen könnte man auch die Küvette C mit der Bezugsflüssigkeit füllen und somit ständig im Strahlengang belassen.During the normal measuring process, the sensitivity of the instrument must be set so that a transmission of 100% is defined. This setting requires the introduction of a reference body into the beam path instead of the object to be tested. This is easily possible with the arrangement according to the invention, since the hoses la, 2a and 3a consist, for example, of polyethylene or a similar flexible material, so that the cuvette C can be easily removed. Instead of this, the cuvette C could also be filled with the reference liquid and thus left in the beam path at all times.

Bei richtiger Anbringung des Entleerungsrohres 3 läßt sich erreichen, daß weniger als 1% der benutzten Flüssigkeit nach der Entleerung in der Küvette zurückbleibt. Für die Absorptionsmessung einer Reihe von Flüssigkeiten mit ähnlicher Absorption ist dieser Flüssigkeitsrest vernachlässigbar klein.With the correct attachment of the drain pipe 3 it can be achieved that less than 1% of the used Liquid remains in the cuvette after emptying. For the absorption measurement of a In the series of liquids with similar absorption, this residual liquid is negligibly small.

Bei sehr genauen Messungen mit stark voneinander abweichenden Absorptionswerten genügt ein einfaches Durchspülen der Küvette durch einmaliges Füllen und Leeren mit der zu untersuchenden Flüssigkeit, um jede Verunreinigung vernachlässigbar klein zu machen.For very precise measurements with widely differing absorption values, a simple one is sufficient Rinsing the cuvette by filling and emptying it once with the liquid to be examined, to make any impurity negligibly small.

Hierzu 1 Blatt Zeichnungen1 sheet of drawings

Claims

1 2 located chamber is in connection, which is based on claims: its lower end can be connected to a suction line.

1. Device for filling and emptying a Also with these cuvette arrangements, however, it is necessary to fill the cuvette by pouring the cuvette into the cuvette vacuum-tight or using a pipette or a 3-way tube one (1) up to the injection syringe before the cuvette is inserted into the top of the cuvette or further up to the optical instrument at the most. This pre-insertion height is sufficient and with a container (B) aisle is tricky and time-consuming, especially since it is pre-connected, which the analysis liquid must be avoided in order to ensure a second; (2) up to the filling level is enough to ensure that the outer surfaces of the cuvette, through which and is connected to a valve (D) and a light should pass through, remain completely clean, third (3) extends to the bottom and is also an object of the invention is to provide a device with the valve (D), and that the valve (D) for filling and emptying a liquid cuvette in a middle position to provide both last 15, in which not only the aforementioned tubes (2, 3 ) closes and empties in two, but also the filling of the cuvette through external positions each one of the tubes (2, 3) with suction via a vacuum line connects a suction line (E). can be.

2. Apparatus according to claim 1, characterized in that the invention is characterized to solve this problem, that the valve (D) automatically in 20 according to the device characterized in that in the center position returns. the cuvette guide three tubes vacuum-tight from above

3. Device according to claim 1, characterized ge Ren, one of which up to the top of the cuvette or indicates that the other end of the supply line extends further up to the filling level and with (la) is connected to the first pipe (1) by a downwardly a container which the analysis device Tube is formed and the connection 25 contains liquid, a second up to the filling level to the analysis liquid in the container (B) by means of a range and connected to a valve and a lifting of the same is effected. third goes to the ground and also with the

4. Apparatus according to claim 3, characterized in that the valve is connected, and that the valve indicates that the supply line (la) closes both last-mentioned tubes at a central position actuating lever (H) of the valve (D) flexibly loaded 30 and in two external positions each one of the pipes is fixed and that the actuating lever (H) connects the one suction line.

Art is arranged that when the container is lifted, the other end of the supply line is preferably used

ters (B) the valve comes in the position in to the first pipe through a downward directed pipe

which forms the pipe (2) reaching up to the filling level and the connection to the analysis liquid is connected to the suction line (E). 35 in the container is effected by lifting the same.

5. Device according to one of the preceding according to a particularly advantageous embodiment claims, characterized in that, in the form of the invention, the supply line is connected to a surrounding area of the pipes (1 to 3) screens flexibly attached to the control lever of the valve and the th of the liquid flow are provided. The operating lever is arranged in such a way that when

6. Apparatus according to claim 1, characterized in that the container lifts the valve into that position indicates that the pipes (1 to 3) come through one in which the pipe reaching up to the filling level Stopper (Λ) are inserted in the cuvette. is connected to the suction line.

7. Apparatus according to claim 5 and 6, that in this way not only the emptying, sondurch characterized in that the screens (S) and the filling of the cuvette are attached to the stopper (A) in a very simple way. 45 ways possible. Filling, emptying and cleaning

the cuvette can be carried out by operating a single lever, whereby according to the mentioned

th embodiment of this operating lever when

Lifting the container by itself is taken 50.

The invention relates to a device for filling the tubes are preferably in a closure

len and emptying a liquid cuvette that is used for stopping. Around the cuvette up to a beoptic Examination of liquids, e.g. being able to fill and empty them at a certain level, an absorption spectrometer is used. two suction pipes are provided, one of which

Crucial to the practical use of one 55 up to the desired level and the other up Liquid cuvette is your filling and cleaning range reaching to the bottom of the vessel. About a barrier option. It is known that the two suction pipes can optionally be used with the complete entorgan emptying of the cuvette with the help of suction tubes through a suction line. A third respectively. In a known arrangement of this type of pipe is to be underneath the reservoir the bottom of the cuvette is connected to a hole 60 searching liquid. The actuation oversight, with the interposition of a lever for the shut-off element, is preferably so on-hand to be operated valve arranged with a suction line that it is operated by means of the storage vessel can be connected. So let the too under- can be.

searching liquid and the cleaning liquid become the essential features of the invention

remove with little effort. 65 below on the basis of a schematic drawing

Another construct, as described, fulfills the same purpose.

tion, in which the lower end of the cuvette is located in an optical instrument using the

an overflow pipe with a cuvette next to the cuvette C has a plug A through