JP2000051715A - Buret - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make easily adjustable the zero point and settable a buret device by inserting the lower end of a liquid supply tube to the inner bottom of a flexible chemical liquid container, inserting the top end of the liquid supply tube through the opening of the buret upper end, making the top end coincide with the zero point in the buret and open downward through a supporting tool. SOLUTION: The one end of a liquid supply tube 6 is passed through a sealing cap 8 and made to open in a chemical liquid 9 in a chemical liquid container 7 which is flexible and made of a transparent or colored synthetic resin. The other end of the tube is inserted through the upper opening 4 of a buret 1 into the buret and made to open on the A-plane as a zero point 10 trough a supporting tool 5. A cock 3 at the lower part of the buret 1 is opened to drop the chemical liquid in the buret 1 for carrying out titration. Thereafter, after the titration reaches the end point, the cock 3 is closed and a scale 2 is read to measure the amt. of the chemical liquid 9 required for the titration work. In order to make the supply amt. of the chemical liquid 9 coincide with the zero point 10 and the initial stage, the container 7 is pressurized, and when the surface level of the chemical liquid exceeds the zero point 10, the pressuring is stopped to stop the supplying of the chemical liquid 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a burette for performing titration of reagents in wet chemical analysis, and more particularly to a burette capable of quickly and accurately replenishing a reagent after titration using a burette. It is about.

[0002]

2. Description of the Related Art A burette is a kind of chemical volume meter which is made to easily drop and discharge an arbitrary liquid or gas. As shown in FIG. It is common to cut a uniform scale, narrow the tip, and have a cock or rubber tube and a glass bulb for adjusting the amount of dropping between them.

[0003] Usually, 25 to 50 ml, the marked lines are all cut to 0.1 ml in the external volume, and are mainly used for titration by filling with a standard solution or rarely a sample solution in volume analysis.

Although there are considerable types of materials and shapes depending on the intended use, the standard structure is generally made of hard transparent glass as shown in FIG. If it is easy to do so, a burette made of colored glass is used.

In the conventional burette, as shown in FIG. 4, after filling a predetermined amount of reagent into the burette, a cock is opened to titrate a required amount of reagent. The amount of reagent required for titration is measured by reading the scale engraved on the burette. When the titration is performed again, it is necessary to replenish the reagent from the upper end of the burette, but in this case, adjusting the zero point on the scale requires considerable skill and time.

Therefore, various improvements have been made and proposed as countermeasures. Japanese Utility Model Laid-Open Publication No. 51-148997 discloses that a solution containing a chemical solution is pressed so that the chemical solution is buretted through a hole provided in the burette. There is disclosed a burette that can automatically adjust the zero point if the position of the hole is adjusted to the zero point because the excess chemical solution is returned to the container while flowing into the container.

Japanese Utility Model Laid-Open Publication No. 53-71490 describes a technique for performing this pressing with a double ball. However, these devices have complicated structures and are extremely troublesome to manufacture. There was a disadvantage that the cost was high.

[0008]

SUMMARY OF THE INVENTION The present invention proposes a burette that can use a conventional existing burette, has a very simple adjustment of zero point and sets the apparatus, and can supply a reagent quickly and accurately. It is.

[0009]

According to the present invention, a lower end of a liquid supply pipe penetrating a closed lid of the liquid medicine container is inserted into a bottom of a flexible liquid medicine container, and a front end of the liquid supply pipe is buretted. The object of the present invention is to provide a burette that is inserted through an opening at an upper end and is opened downward through a support in accordance with a zero point position in the burette.

In the above invention, the chemical solution container is acid-resistant,
It is preferable that the container is made of a flexible material such as a synthetic resin having excellent alkali resistance and chemical resistance, and is formed so that the pressure inside the container can be arbitrarily adjusted by pressing the container.

[0011] Further, the support is formed on the inner wall of the burette so as to be fixed or slidable up and down, and is supported and fixed with the tip of the liquid supply pipe positioned downward in accordance with the zero point of the burette. Is preferred.

[0012]

The burette according to the present invention is constructed as described above, and by pressing the chemical solution container containing the chemical solution from the outside with the fingers, the internal pressure is increased and the chemical solution in the container is viewed through the liquid supply pipe. Even if the supply is stopped at any point when it is equal to or higher than the zero point (reference point), the surplus chemical liquid flows back (returns) into the liquid medicine container via the liquid supply pipe according to the siphon principle. Therefore, if the tip of the liquid supply tube is set at a predetermined position (zero point: reference point), the zero point can be automatically adjusted when supplying the liquid medicine after the titration operation. Hereinafter, embodiments of the present invention will be described.

[0013]

FIG. 1 is an overall explanatory view showing an example of an apparatus according to the present invention, FIG. 2 is an explanatory enlarged side view showing an example of a support, and FIG. 3 is a sectional view taken along line LL of FIG. FIG. 4 is a side view of a conventional burette.

In the figure, reference numeral 1 denotes a conventionally used hard glass burette with a cock, 2 denotes a scale graduated to 0.1 ml in an outer volume, and 3 denotes a drop amount adjusted at the time of titration. 4 is an opening which is open at the upper end of the burette, and 5 is a support for supporting and fixing the distal end of the liquid supply pipe 6. Is supported and fixed to the zero point 10 of the burette 1. The support member 5 is made of a hard and transparent synthetic resin made of an acid-resistant, alkali-resistant, or chemical-resistant liquid, and supports a liquid supply pipe 6 at a substantially central portion thereof. A ring-shaped outer peripheral portion 11 shown in FIG. The liquid supply pipe 6 is formed so as to be slidable up and down along the inner wall, and is supported and fixed by opening the front end of the liquid supply pipe 6 in accordance with the position of the zero point (the surface A in FIG. 1).

Reference numeral 7 denotes a chemical solution container for storing a chemical solution 9 used for volume analysis. The container 7 is a transparent or colored flexible material made of synthetic resin having excellent resistance to acids, alkalis and chemicals. (Material similar to that of the liquid supply pipe 6) is formed so that the internal pressure of the container 7 can be arbitrarily adjusted by pressing the container 7 from outside with fingers.

Reference numeral 8 denotes a hermetic lid for hermetically closing the chemical solution container 7,
The liquid supply pipe 6 penetrates a substantially central portion of the closed lid 8, and the tip of the liquid supply pipe 6 is immersed in the chemical solution 9 in the container 7.

That is, one end of the liquid supply pipe 6 is opened through the hermetic lid 8 into the chemical solution 9 in the chemical solution container 7, and the other end is formed from the upper end opening 4 of the burette 1 as described above. It is inserted into the burette 1, and is opened through the support 5 at the above-mentioned A surface at the zero point 10.

The cock 3 at the lower part of the burette 1
Is opened and the liquid medicine in the burette 1 is dropped to perform a titration operation. When the end point is reached, the cock 3 is closed, the scale is read, and the amount of the chemical solution 9 required for the titration operation is measured.

Next, when the chemical solution container 7 is pressed from the outside with fingers or the like to increase the air pressure in the container 7, the chemical solution 9 rises in the liquid supply pipe 6 immersed in the chemical solution 9, The chemical solution 9 is supplied into the burette 1 from the other end installed in the burette 1.

The supply amount of the chemical solution 9 is set to the same zero point 10 (A
In order to match with (surface), the pressing of the container 7 is stopped when the liquid surface of the chemical solution exceeds the zero point 10, and the supply of the chemical solution 9 is stopped.
By doing so, the excess chemical solution 9 flows back through the feed pipe 6 and returns to the chemical solution container 7 according to the siphon principle.

When the liquid level reaches the zero point 10, the liquid level moves away from the tip of the liquid supply pipe 6, so that the principle of the siphon is no longer applied, the backflow of the chemical liquid 9 stops, and the surface of the chemical liquid 9 is placed in the burette 1. Will match the zero point. Thus, the titration operation may be started again.

In order to supply the chemical solution 9 again after the titration operation is completed, the zero point 10 can be automatically adjusted by performing the above-described operation. No need to adjust.

Further, since the position of the tip of the liquid supply pipe 6 in the burette 1 can be freely changed by the support tool 5, the position of the zero point 10 can be adjusted as required.

[0024]

The present invention is constructed as described above, and can use an existing burette. When replenishing a drug solution after titration, the tip of the liquid supply pipe is set at the reference point (zero) in the burette. (Point), even if the chemical solution is supplied beyond the reference point, the excess is returned back to the chemical solution container by the siphon principle, and the reference point is automatically determined.

In addition, since the replenishment of the drug solution after the titration can be carried out quickly and accurately, the analysis operation can be carried out accurately and promptly without requiring much skill.

[Brief description of the drawings]

FIG. 1 is an overall explanatory view showing one embodiment of an apparatus according to the present invention.

FIG. 2 is an explanatory enlarged side view showing an example of a support according to the present invention.

FIG. 3 is a sectional view taken along line LL of FIG. 2;

FIG. 4 is a side view of a conventional burette.

[Explanation of symbols]

 1-buret 2-scale 3-cock 4-opening 5-support member 6 liquid supply pipe 7-chemical liquid container 8-sealed lid 9-chemical liquid 10-zero point (base point) A-base plane

Claims (3)

[Claims] 1. A lower end of a liquid supply pipe penetrating a sealed lid of the container is inserted into an inner bottom of a flexible liquid medicine container, and a leading end of the liquid supply pipe is inserted from an opening at an upper end of a burette. A burette characterized by being opened downward through a support in accordance with a zero point position in the burette. 2. The chemical solution container is made of a synthetic resin or the like having excellent resistance to acids, alkalis and chemicals, and is formed so that the pressure inside the container can be arbitrarily adjusted by pressing the container. The viewlet according to claim 1. 3. The supporter is formed on the inner wall of the burette so as to be fixed or slidable up and down, and the supporter is supported and fixed with the distal end of the liquid supply pipe positioned downward in accordance with the zero point of the burette. The viewlet according to 1.