JPH11271331A - Washing mechanism of sampling nozzle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the washing mechanism of a sampling nozzle for securely eliminating a residue causing carry-over. SOLUTION: In the washing mechanism of a sampling nozzle 1, a washing liquid is supplied into a washing pot 5 for washing a tip part 3 while the tip part 3 of the sampling nozzle 1 for quantitative injection is being inserted into the washing pot 5. In the washing mechanism, a small-diameter part 9 that matches the shape of the tip side of the sampling nozzle 1 is formed in the washing pot 5 and at the same time a washing liquid is supplied to the small- diameter part 9. Also, the washing liquid is sucked and delivered from the thin-diameter part 9 or a position that is lower than it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanism for washing a sampling nozzle for aspirating and sampling a predetermined amount of a liquid such as blood contained in a sample container in an automatic analyzer such as a chemiluminescent enzyme immunoassay. About.

[0002]

2. Description of the Related Art In the above-mentioned chemiluminescent enzyme immunoassay, a sample such as blood (also referred to as a specimen) is suctioned by a sampling nozzle of a liquid suction device in a fixed amount and supplied to a measurement system. (Car
In order to prevent ry over, a residue such as a sample previously sampled from being carried into the next sample), it is necessary to wash the sampling nozzle with an appropriate washing liquid at the end of each sampling. As shown in FIG.

That is, in FIG. 4A, reference numeral 41 denotes a sampling nozzle for quantitative injection, which is held by a holding mechanism (not shown) so as to be movable in the horizontal and vertical directions, via a liquid flow path (not shown). It comprises a nozzle body 42 connected to a dispenser such as a syringe, and a nozzle tip 43 connected to a lower portion of the nozzle body 42 and having a smaller diameter than the nozzle body 42. Reference numeral 44 denotes a cylindrical cleaning pot for cleaning the sampling nozzle 41, which is open at the top and closed at the bottom. An introduction hole 47 for introducing the cleaning liquid 46 is formed in an upper portion of the side wall 45 of the cleaning pot 44, and a discharge hole 48 for discharging the cleaning liquid 46 is formed in a lower portion of the side wall 45. Although not shown, a cleaning liquid introduction pipe is connected to the introduction hole 47, and a cleaning liquid discharge pipe provided with a suction pump and an electromagnetic valve is connected to the discharge hole 48.

In the cleaning mechanism of the sampling nozzle having the above-described structure, the sampling nozzle 41 is immersed in the cleaning liquid 46 while the cleaning liquid 46 is contained in the cleaning pot 44. Then, the lower periphery including the nozzle tip 43 of the sampling nozzle 41 is washed by being inserted into the washing pot 44. After washing the outer periphery, the washing pot 4
In a state where the cleaning liquid 46 is discharged from the cleaning nozzle 4, the cleaning liquid is introduced into the sampling nozzle 41 through the main body 42 via the infusion line to clean the inside of the sampling nozzle 41. In particular, when performing highly accurate measurement, the external cleaning and the internal cleaning are performed using a new cleaning liquid.

[0005]

A diluent (buffer solution) for diluting a specimen is used for cleaning the sampling nozzle 41. However, in the conventional sampling nozzle cleaning mechanism, the following is used. There was such a problem. That is, since the outside of the nozzle is cleaned by immersing a part of the nozzle body 42 of the sampling nozzle 41 in the cleaning liquid 46, the cleaning liquid side wall adhered to the outer periphery of the nozzle body 42 as shown in FIG. At the end of the nozzle tip 43, the water droplets 49 fall into the sample container 50 and contaminate the sample 51 in the sample container 50 in some cases. In this case, the cleaning liquid remaining inside the nozzle may be drawn by the water droplet 49.

As described above, in the conventional cleaning mechanism of the sampling nozzle, even if the sampling nozzle 41 is cleaned with the cleaning liquid, the residue that causes carryover cannot always be completely removed. It was likely that blood and other tests would be adversely affected.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-mentioned circumstances, and an object of the present invention is to provide a cleaning mechanism for a sampling nozzle capable of reliably removing a residue that causes carryover.

[0008]

In order to achieve the above-mentioned object, the present invention provides a cleaning liquid which is supplied to a cleaning pot while a tip of a sampling nozzle for quantitative injection is inserted into the washing pot. In the washing mechanism of the sampling nozzle that is configured to wash the inside of the washing pot, a small-diameter portion that matches the shape of the tip side of the sampling nozzle is formed, and the tip of the sampling nozzle is formed in the small-diameter portion. The cleaning liquid is supplied to the small-diameter portion in the positioned state, and the cleaning liquid is suctioned and discharged from the small-diameter portion or a position lower than the small-diameter portion.

In the cleaning mechanism of the sampling nozzle having the above-described structure, the thin tip of the sampling nozzle is located at the small-diameter portion of the cleaning pot, and in this state, suction is performed while supplying the cleaning liquid to the small-diameter portion. The aspirator effect acts on the tip of the nozzle, whereby the liquid inside the tip of the nozzle is completely discharged.

[0010]

Embodiments of the present invention will be described with reference to the drawings. 1 to 3 show one embodiment of the present invention. FIG. 1 is a view schematically showing an example of a sampling nozzle cleaning mechanism of the present invention, FIG. 2 is a perspective view showing a main part of the cleaning mechanism, and FIG. FIG. 3B is a schematic cross-sectional view of the cleaning pot.

In FIGS. 1 and 2, reference numeral 1 denotes a fixed-quantity injection sampling nozzle which is held by a holding mechanism (not shown) so as to be movable, for example, in a rotational direction and a vertical direction. As shown in FIG. Diameter nozzle body 2
And a small-diameter nozzle tip 3 connected to the tip (lower end) side thereof
And a material excellent in chemical resistance and heat resistance, such as glass or ethylene tetrafluoride resin, or stainless steel. Reference numeral 4 denotes a flexible connection pipe connected to the nozzle body 2.

Reference numeral 5 denotes a cleaning pot for cleaning the tip of the sampling nozzle 1, which is made of a material having excellent chemical resistance and heat resistance such as tetrafluoroethylene resin or stainless steel. It consists of a cylindrical part 6 and a square block part 7. A hole 8 having a slightly large diameter is formed in the inside of the cylindrical portion 6 over its entire length, and a square block portion 7 connected to the cylindrical portion 6 is connected to the large diameter hole 8 and has a concentric small diameter. Hole 9 is formed. That is, two holes 8 having different diameters are provided inside the cleaning pot 5.
9 is formed.

More specifically, the upper hole (large-diameter portion) 8 of the cleaning unit 10 is formed as a hole having a larger diameter than the nozzle body 2 of the sampling nozzle 1, and the lower hole (small-diameter portion).
Reference numeral 9 denotes a hole that is thinner than the nozzle body 2 of the sampling nozzle 1, slightly larger in diameter than the nozzle tip 3, and has a depth substantially equal to the length of the nozzle tip 3. And
At an appropriate position on the side of the small-diameter portion 9, as shown in FIG. 3A, a liquid introduction hole 11 is opened in the horizontal direction. As shown in (B),
It is slightly eccentric from the small diameter portion 9. In addition, a liquid discharge hole 12 is opened vertically below the small diameter portion 9.

A liquid supply path for supplying a cleaning liquid and a flow path for discharging the liquid after cleaning are connected to the sampling nozzle 1 and the cleaning pot 5 configured as described above. Hereinafter, this will be described with reference to FIG. First, 13 is a liquid introduction hole 11 of the cleaning pot 5 (FIG. 3).
(See FIG. 1A), a first cleaning liquid flow path for supplying a cleaning liquid for cleaning the outer periphery of the tip of the sampling nozzle 1, and a three-way valve 14. Dispenser 15 and alkaline cleaning liquid tank 16
Is connected.

Reference numeral 17 denotes a liquid discharge hole 1 of the washing pot 5.
2 (see FIG. 3A). The liquid discharge path 17 is for discharging the liquid after washing. The liquid discharge path 17 is suctioned through a two-way valve 18. A pump 19 is provided. Note that the downstream side of the suction pump 19 is connected to a liquid disposal section (not shown).

Reference numeral 20 denotes a second cleaning liquid flow path connected to the sampling nozzle 1 via the connection pipe 4. The flow path 20 supplies a cleaning liquid for cleaning the inside of the sampling nozzle 1. , The three-way valve 2
A diluent tank 22 and a dispenser 23 are connected downstream of the three-way valve 21, and another three-way valve 2 is provided.
A distilled water tank 26 and another dispenser 27 are connected to each other via 4 and 25.

In FIG. 2, reference numeral 28 denotes a sample container containing a sample 29 such as blood.

Next, the operation of the cleaning mechanism of the sampling nozzle having the above configuration will be described. Sampling nozzle 1
In order to supply the sample 29 in the sample container 28 to a measurement system (not shown), the sampling nozzle 1 is moved to the sample container position, and then the nozzle tip 3 is moved to the sample container 28.
After a predetermined amount of the sample 29 in the sample container 28 is aspirated by operating, for example, the dispenser 23 or 27, the sampling nozzle 1 is appropriately moved and supplied into the measurement system such as a cell. After this sampling, cleaning of the sampling nozzle 1 performed before the next sampling is performed, for example, as follows.

The dispenser 15 is operated in advance to store a predetermined amount of the alkaline cleaning liquid in the alkaline cleaning liquid tank 16 in the dispenser 15. On the other hand, the three-way valve 21 is operated to make the diluent tank 22 communicate with the second cleaning liquid flow path 20.

Then, the tip of the sampling nozzle 1 after the sampling is accommodated in the washing pot 5. In this case, the nozzle tip 3 of the sampling nozzle 1
Is preferably held at the small diameter portion 9 of the washing pot 5.

Next, the three-way valve 14 is operated, and
5 is communicated with the first cleaning liquid channel 13. In this state, the two-way valve 18 is operated to open it, and the suction pump 19 is operated. By the suction operation of the suction pump 19, the alkaline cleaning liquid in the infusion device 15 is vigorously introduced into the small-diameter portion 9 of the cleaning pot 5 through the first cleaning liquid flow path 13 and the liquid introduction hole 11. After cleaning the outer periphery of the nozzle tip 3 including the portion that has come into contact with the sample at the time of sampling, the liquid reaches the liquid discharge passage 17 through the liquid outlet hole 12 below the small-diameter portion 9, and further passes through the suction pump 19 to the liquid disposal unit. Leads to.

On the other hand, by the suction operation of the suction pump 19, the diluent in the diluent tank 22 is introduced into the sampling nozzle 1 through the second cleaning liquid flow path 20, and this diluent cleans the inner surface of the sampling nozzle 1. As a result, the liquid reaches the liquid disposal section in the same manner as the alkaline cleaning liquid.

As described above, when the sampling nozzle 1 is washed, the sampling nozzle 1
Is located in the small-diameter portion 9 of the cleaning pot 5, and in this state, while supplying the cleaning liquid to the small-diameter portion 9 and performing suction, the cleaning liquid is supplied to the nozzle tip 3 with vigor. After the cleaning, the liquid reaches the liquid discharge passage 17 through the liquid outlet hole 12.
When the cleaning liquid is supplied to the nozzle tip 3 vigorously, an aspirator effect works at the nozzle tip 3, and a negative pressure is generated at the nozzle tip 3. Even if it remains, it can be reliably discharged.

In the above embodiment, the introduction hole 11 for the liquid for cleaning the outer periphery of the nozzle tip 3 is formed in the small-diameter portion 9.
3B, the liquid flows around the nozzle tip 3 in the small-diameter portion 9 as shown by an arrow in FIG. The effect of cleaning the outer periphery of the nozzle tip 3 is enhanced.

The present invention is not limited to the above embodiment, but can be implemented in various modifications. For example, the shape of the washing pot 5 may be cylindrical in appearance, or may be a rectangular parallelepiped shape, and a small-diameter portion 9 that fits the shape of the nozzle tip 3 therein.
What is necessary is just to form. The inner diameter of the small-diameter portion 9 may be set slightly larger than that of the nozzle tip 3.

The position where the liquid introduction hole 11 formed in the small-diameter portion 9 is opened is set such that the nozzle tip 3 inserted into the small-diameter portion 9 can be washed over substantially the entire length thereof. I just need. Further, the liquid discharge port 12 formed in the small-diameter portion 9 may be a side surface of the cleaning pot 5 as long as the liquid after cleaning can be completely discharged.

[0027]

According to the cleaning mechanism for a sampling nozzle of the present invention, the tip of the sampling nozzle can be surely cleaned and the residue causing carryover can be surely removed. It can be suitably used for various automatic analyzers such as an apparatus, and can contribute to improvement of the measurement accuracy.

[Brief description of the drawings]

FIG. 1 is a view schematically showing an example of a sampling nozzle cleaning mechanism of the present invention.

FIG. 2 is a perspective view showing a main part of a cleaning mechanism of the sampling nozzle.

3A and 3B are diagrams illustrating an example of a cleaning pot, wherein FIG. 3A is a schematic longitudinal sectional view, and FIG. 3B is a schematic longitudinal sectional view.

4A and 4B are diagrams for explaining a conventional technique, in which FIG. 4A is a diagram showing a conventional cleaning pot, and FIG. 4B is a diagram for explaining a problem.

[Explanation of symbols]

1 ... sampling nozzle, 3 ... nozzle tip, 5 ... washing pot, 9 ... small diameter part.

Claims (1)

[Claims] 1. A cleaning mechanism for a sampling nozzle, wherein a cleaning liquid is supplied into a cleaning pot while the tip of the sampling nozzle for quantitative injection is inserted into the cleaning pot to clean the tip. Inside the pot, a small-diameter portion is formed to match the shape of the tip of the sampling nozzle, and the cleaning liquid is supplied to the small-diameter portion with the tip of the sampling nozzle positioned at the small-diameter portion. And a cleaning mechanism for the sampling nozzle, wherein the cleaning liquid is sucked and discharged from a small diameter portion or a position lower than the small diameter portion.