JPS5839411Y2 - How do you know what to do? - Google Patents

Description

[Detailed description of the invention] The present invention relates to a sample nozzle cleaning device for an automatic chemical analyzer used for colorimetrically measuring components such as protein, albumin, calcium, urea, nitrogen, and cholesterol in serum samples. be.

Since automatic chemical analyzers can keep the reaction time constant, that is, the reaction time can be made the same for each test solution, it is possible to shorten the reaction time when the relationship between time and reactivity is constant. It has the advantage of being predictable and maintaining high measurement accuracy, and since all operations are mechanized, the measurement values are not affected even if the person operating the device changes. .

However, in automatic chemical analyzers, it is difficult to automate the cleaning of the sample nozzle that aspirates the sample and dispenses it into the reaction tube after dispensing. It was normal.

That is, the syringe 2 causes the nozzle 1 to suck and eject the sample.
A compressible tube 3 is connected to the tube, and a valve 4 that can be shut off by crushing the tube is provided in the middle of the tube as shown.

Then, an air nozzle 5 is provided so as to be directed toward the outer periphery of the tip of the sample nozzle 1, and this air nozzle and the tube 3 are connected to a common air pressure source.

When cleaning the nozzle after dispensing a sample by such means, open the valve 4, which was closed during the sample dispensing operation, to allow compressed air to flow through the tube 3 into the sample nozzle 1 as shown by the arrow, and also to clean the air nozzle. 5, compressed air is blown onto the outer periphery of the tip of the sample nozzle 1.

As a result, the sample nozzle has a tendency to blow off the sample adhering to the inside and outside thereof, and is cleaned, but the sample adhering to the outer periphery of the tip of the nozzle 1 is difficult to completely remove.

As shown in 6, a small amount (approximately 1 μm) remains.

This causes the previous sample to be mixed into the next sample when it is dispensed, which seriously affects measurement accuracy.

The present invention has developed a sample nozzle cleaning device that does not cause such inconvenience, that is, can clean the sample nozzle almost completely.

Hereinafter, the present invention will be explained in detail with reference to the illustrated embodiments.
3 and 3 show an example of the configuration of the device of the present invention.

The sample nozzle 1 and the air nozzle 5 are fixed to the tip of a rotating arm 8, and this arm is pivotally connected to a rotating shaft 10 by a pin 9.

The arm 8 is supported by a fixed cam 11, so that when the arm 8 rotates together with the shaft 10, the tip of the arm can be lowered directly above the sample container 12 and reaction tube 13 as the arm 8 rotates.

The sample container 12 is intermittently conveyed sequentially through the transfer passage 14, and the reaction tubes 13 are disposed concentrically on a turret 15 and are sequentially conveyed by the intermittent rotation of this turret.

The operation of dispensing the sample in the sample container 12 into the reaction tube 13 using the nozzle 1 is performed as follows.

That is, the valve 4 is closed as shown in the second figure, and the arm 8 is rotated about the shaft 10 to bring the nozzle 1 directly above the sample container 12.

At this time, the nozzle 1 is lowered below the level of the sample in the sample container 12 under the action of the cam 11.

In this state, the syringe 2 is operated to suck a predetermined amount of sample to the tip of the nozzle 1, and then the arm 8 is moved by the shaft 10.
is rotated so that its tip is positioned above the reaction tube 13.

At the beginning of this rotation, the tip of the arm 8 is lifted together with the nozzle 1 under the action of the cam 11, and the reaction tube 1 remains at this raised level.
3, and the cam 11 is again positioned above the reaction tube 13.
Due to this action, the nozzle 1 descends to a position where it enters the reaction tube 13.

In this state, when syringe 2 is discharged, nozzle 1
The sample that has been sucked into the tip of the tube is discharged into the reaction tube 13, and mixes with the reagent in the reaction tube to become a measurement test liquid.

After the sample dispensing action described above, by rotating the arm 8 in the opposite direction using the shaft 10, the tip of the nozzle 1 reversely follows the above-mentioned path (indicated by the dashed line 16 in FIG. 2) and returns to the source. Return to position.

In the present invention, an overflow device 18 is provided in the path 16 at the tip of the sample nozzle 1 to generate an overflow 17 of washing water.

This overflow device has a double wall structure with an opening at the top end, and has an inner chamber 18a and an outer chamber 18b.
A water supply hose 19 and a drainage hose 2 are installed on the bottom wall of , 18b, respectively.
Connect 0.

Therefore, the overflow device 18 generates an overflow 17 of the wash water in the process of supplying the wash water to the inner chamber 18a from the water supply hose 19, passing through the overflow sharp outer chamber 18b, and removing it from the drain hose 20.

The sample nozzle 1 is transferred along the liquid surface of the overflow 17 of the cleaning water.

That is, the tip of the sample nozzle 1 is transferred while being slightly above the opening upper end surface of the inner chamber 18a of the overflow device 18 and immersed below the liquid level of the overflow 17 during return movement.

Thus, the outer periphery of the sample nozzle 1 is washed with washing water while its tip passes through the overflow 17 of washing water after sample dispensing, and is then squeezed into and out of the sample nozzle as described above with reference to FIG. Complete the specified cleaning of the sample nozzle by blowing air.

Note that the tip of the sample nozzle is connected from the sample container 12 to the reaction tube 13.
Since the sample passes through the same route 16 on the way to the sample, it passes through the wash water overflow 17 while the sample is being aspirated.However, since the inner diameter of the nozzle is extremely small, there is no inconvenience that the wash water may enter the nozzle tip. It will never occur.

If this is a concern, route 16 should be designated as a dedicated route after sample dispensing, and nozzle 1 directed from sample container 12 to reaction tube 13 should be used.
The cam 11 may be constructed in such a shape that a path 21 that bypasses the overflow 17 can be separately set as a movement path as shown by the dotted line in FIG.

Although not shown, if the overflow device 18 has an oval cross section that is long in the direction of the path 16, instead of having a circular cross section,
It takes a long time for the tip of the nozzle 1 to pass through the overflow 17, and during this time, the cleaning water can be sucked into the nozzle tip and discharged, and not only the outer periphery of the nozzle but also the inside of the nozzle can be cleaned with the cleaning water. , the cleaning effect is further improved.

Since the device of the present invention is constructed as described above, there is no problem of the sample remaining on the outer periphery of the tip of the sample nozzle and the shoe after cleaning, which greatly contributes to improving the measurement accuracy of the analyzer.

Moreover, this purpose can be achieved by simply providing the overflow device 18 in the return path of the nozzle tip, so the device is simple, and since it is automatically cleaned during the return movement of the nozzle tip, the cleaning path can be There is no need for separate settings, almost no time is required for cleaning, and at the same time there is no need for a device for moving the nozzle tip along a separate path for cleaning.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a conventional sample nozzle cleaning device, FIG. 2 is an explanatory diagram of the sample nozzle cleaning device of the present invention, and FIG. 3 is a plan view thereof. 1...Sample nozzle, 2...Syringe,
3... Flexible tube, 4... Valve, 5...
... Air nozzle, 8 ... Rotating arm, 9
...Pivot pin, 10...Axis, 11...
...Cam, 12...Sample container, 13...
... Reaction tube, 14 ... Sample container transfer passage, 1
5...Reaction tube turret, 16...Sample nozzle tip movement path, 17...Washing water overflow 18...Overflow device, 1
9...Water supply hose, 20...Drainage hose.

Claims (1)

[Scope of utility model registration request] In an automatic chemical analyzer equipped with a sample nozzle that aspirates a sample in a sample container, discharges it into a reaction tube, and then transfers it onto the next sample container, the tip of the sample nozzle that points from the reaction tube onto the sample container of the method. A sample nozzle cleaning device for an automatic chemical analyzer, comprising an overflow device that generates an overflow of cleaning water in the return movement trajectory of the sample nozzle, and cleaning the tip of the sample nozzle while passing through the overflow of the cleaning water.