JPS58143269A - Method and device for controlling descending of pipette in automatic biochemical analysis device - Google Patents

Abstract

PURPOSE:To eliminate the corrosion of a liquid level detecting means and the contamination of specimen liquid, etc. owing to the corrosion and to suck the liquid accurately by disposing optical fibers for emission and incidence of light near a pipette and controlling the descending of the pipette until the light from a light source reflects on the surface of the liquid and enters the fiber. CONSTITUTION:An optical fiber F1 for emission of light and an optical fiber F2 for incidence of light are provided in such a way that light source light 2 irradiates a liquid surface Ka at a prescribed angle theta1 and that the light irradiated to the liquid surface and reflected from the liquid surface is made incident to the fiber F2 at theta2=theta1 in the reflection angle theta2 by a reflection surface 3 and a semipermeable membrane 4 in the stage of sucking a reagent or test liquid automatically with a pipette P in an automatic biochemical analysis device. A detecting means is provided to a pipette holder 1 in such a way that the descending motion of the pipette P is controlled by a driving means. Since the contact of the detecting means with the liquid surface is obviated in such a way, the liquid is sucked accurately without corrosion and without contamination of the liquid, etc. owing to the corrosion.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for controlling pipette descent in an automatic biochemical analyzer.

As is well known, in biochemical analysis, it is essential to accurately weigh the amount of specimen and reagent in order to maintain and improve data reliability. Detecting the liquid level of the reagent is extremely important in ensuring the sufficient amount of sample to be sucked into the pipette.

Conventionally, as a device for detecting the liquid level in a container and lowering a pipette, an electrode bar is placed adjacent to a metal pipette (P), as shown in Fig. 1. A pipette lowering control device configured to lower the pipette P until a conductive liquid K such as a sample is interposed between the electrode rod and the pipette P and detect the liquid level h in the container B is preferable. Are known.

However, in the conventional pipette lowering control device, electric current flows between the electrode rod and the metal pipette (P), which tends to cause electrolytic corrosion, resulting in deterioration and deterioration of the sample and reagent. This method has problems such as making it easy to make mistakes in controlling the descent of P (pipette or pipette), and also requires cleaning the electrode rod when aspirating other reagents, making the cleaning device complicated. There were also problems.

This invention was made in view of the current situation, and
The objective is to create a pipette that is easy to handle, which can be made of a material that does not cause electrolytic corrosion, and which can detect the liquid level without bringing the liquid level detection means into contact with the liquid, and can always accurately control the pipette downward. The present invention aims to provide a method and apparatus for controlling pipette descent in an automatic chemical analyzer.

In order to achieve such an object, the present invention provides a pipette lowering mechanism in the biochemical automatic analyzer W that sucks the liquid contained in a container and sends the sucked liquid to another container. In the control method, a light output fiber and a light input fiber are arranged near the pipette, and the light source light output from the output fiber is reflected on the liquid surface and enters the light input fiber. The pipette was controlled to descend until the

In addition, in this invention, in order to implement the above method,
A pipette lowering control device M in an automatic biochemical analyzer configured to aspirate liquid contained in a container and send the liquid to another container is connected to a light output fiber disposed near the pipette. When the light source light emitted by this light output fiber is reflected on the surface of the liquid in the container and enters the light input fiber, this is detected by an appropriate detection means and the pipette is activated. The pipette descending device is driven and controlled to stop the descending movement.

Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.

As shown in FIG. 2, the pipette lowering control device according to this embodiment drives a pipette P for sucking up a reagent or sample made of a non-metallic material such as glass using a pulse motor, a servo motor, etc. It is composed of a light output fiber F1 and a light input fiber F, which are fixedly held in a pipette holder 1 that is guided up and down by a person.The light output fiber F1 transmits the light source light 2 from the tip of the light output fiber F. The light is irradiated onto the surface of the reagent or sample in the container B, and the reflected light reflected from this part surface Ka is collected through the light input fiber F2, and sent to the detection means S that detects the liquid surface height h. and sends the data, and the detection means S detects and pipets the data)P
The driving means A of the pipette P is controlled to stop the descent φ of the pipette P.

The light output fiber F1 and the light input fiber F2 have the same structure as known optical communication fibers, but the light output fibers are designed at a predetermined angle with respect to the light source light 2, as shown in FIG. A reflective surface 3 is formed at the tip so as to irradiate the part surface Ka at θ1, and the light source light 2 reflected by the reflective surface 3 is transferred to a semi-transparent membrane tilted inside the tip of the light output fiber F1. 4 and the angle is corrected to a predetermined angle θ1.
The light is irradiated from the tip of the light output fiber F.

Note that the tip of the light input fiber F2 is connected to the light output fiber F,
The light source light 2 irradiated at a predetermined angle θ is reflected by the surface Ka at a predetermined angle θ2, and the reflected light can enter at a right angle (θ1-02).

Therefore, according to the pipette lowering control device according to the above embodiment, the pipette P is slowly lowered by the drive device A when a sample or reagent is aspirated. At this time, the light source light 2 continues to be irradiated from the light output fiber F, but the part surface Ka
If the distance to the point P is large, the light source light 2 is reflected by the surface Ka of the part, but does not enter the light input fiber F2, so it continues to descend by P. and Bipetsu)
When P descends to a predetermined position, that is, the optimal position,
Surface Ka of the 2nd part of the light source irradiated from the fiber island for light emission
The light is reflected at a predetermined angle θ and enters the light input fiber F2. In this state, the detection means S operates to stop the driving means A, so that the pipette P stops descending, and the suction and transfer of the sample, reagent, etc. is started.

Note that the line DL shown by the imaginary line in Fig. 2 is the lowest limit position of the pipette P, and when the pipette P has descended to this position, the pipette P can aspirate the sample K. It rises without any warning and is recorded as an error in the data program.

Therefore, in the pipette lowering control device according to this embodiment, the light output and light input fibers F, which are the liquid level detection means, are
, l The liquid level height h without bringing F2 into contact with the liquid.
Since the downward movement of the pipette can be stopped by detecting this, the above-mentioned fibers F, F2 will not be electrolytically corroded, and when aspirating other reagents or specimens K, only the pipette P needs to be cleaned. Therefore, the cleaning equipment can be simplified, and since the pipette P itself can be made of non-electrolytic corrosion material such as non-metal, the quality of the sample, reagent, etc. K does not deteriorate, and the reliability of data can be maintained and improved. In addition, the pipette P and the sample or reagent can be continuously lowered to a predetermined depth regardless of the increase or decrease in the amount of the sample or reagent.

In the above embodiment, the light output fiber F is configured as described above, but the present invention is not necessarily limited to this, and may be used as a prism, etc. In short, any means may be used as long as the source light 2 is irradiated onto the liquid surface Ka at a predetermined angle θ from the light output fiber F1.

Since this invention includes the above-described configuration, the pipette and the liquid level detection means are not electrolytically corroded by the specimen, etc., thereby preventing deterioration of the specimen, etc., and maintaining and improving the reliability of data.
Cleaning is easy, and since the pipette can always be controlled to descend to a predetermined depth of the sample, the pipette can accurately aspirate the sample.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram schematically showing the configuration of a conventional pipette descent control device, FIG. 2 is an explanatory diagram schematically showing the configuration of a pipette descent control device according to an embodiment of the present invention, and FIG. FIG. 3 is a cross-sectional view of the tip of the light-emitting fiber. A...Driver 1!9 B...Container F...
...Fiber for light output F2...Fiber for light entry K
...Liquid P...Pipette S...
Detection means 2... Light source light patent applicant Nippon Techtron Co., Ltd. No. f I'XI %2) Power procedure amendment (voluntary) 1. Display of the case 1982 Patent Application No. 027198 2, Title of the invention Method for controlling pipette descent in an automatic biochemical analyzer and its device 3, Person making the amendment Relationship to the case Patent applicant address 4-chome Nakamachi, Koganei City, Tokyo No. 13, No. 14, No. 4, Date of amendment order (voluntary) 5, Drawing subject to amendment 6, Contents of amendment -1 H-1 →

Claims (1)

[Scope of Claims] 1) A method for controlling the descent of a pipette in an automatic biochemical analyzer that aspirates a liquid contained in a container and sends the aspirated liquid to another container, in which: The pipette is provided with a light output fiber and a light input fiber, and the light source light emitted from the light output fiber is reflected on the liquid surface, and the pipette is operated until the reflected light enters the light input fiber. A pipette descending control method in an automatic biochemical analyzer, characterized in that the pipette is controlled to descend. 2) In a pipette lowering control device in an automatic biochemical analyzer that aspirates liquid contained in a container and sends it to another container, there is a light output fiber and a light input fiber in the vicinity of the pipette. When the light source light emitted from this light output fiber is reflected on the surface of the liquid in the container and enters the light input fiber, this is detected by an appropriate detection means and the downward movement of the pipette is stopped. A pipette lowering control device for a biochemical automatic analyzer, comprising a pipette lowering device.