JPH04898Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a pipetting device, and particularly to a pipetting device suitable for aspirating liquid from a container with a rubber stopper.

[Prior art and its problems]

A conventional pipette device includes a pipette shaped like a syringe needle, an arm that holds the pipette at one end, a shaft that pivots the other end of the arm, and a position where the arm rotates around the shaft to aspirate liquid. a rotational drive device that rotates and transfers the pipette from the pipette to a liquid discharge position and a cleaning position at a predetermined timing; and a vertical drive device that moves the pipette up and down at each of the positions.
It is generally composed of.

In such a conventional pipetting device, if the upper end of the container containing the liquid to be aspirated is open, there will be no problem in the suction operation of the liquid with this pipette, but the upper end of the container If the pipette is blocked by a rubber stopper, the pipette is likely to bend and break due to the frictional resistance when the pipette is inserted into the rubber stopper.For this reason, conventionally, the rubber stopper has to be manually removed one by one. Therefore, it is necessary to set it in an automatic analyzer or the like, which is a very complicated process and poses problems such as the risk of infection during tests for AIDS and the like.

In addition, various conventional pipette devices have been proposed in which the pipette is configured to be able to penetrate the rubber stopper, but all of these require a significant improvement in the material of the pipette. This results in high costs, and there is also the problem that it is difficult to install sensors for detecting the liquid level.

This invention was devised in view of the current situation, and its purpose is to easily aspirate liquid from a container with a rubber stopper in place without bending or damaging the pipette. It is an object of the present invention to provide a pipette device which is simple in construction and which does not require a separate liquid level detection means at a low cost.

[Means for solving problems]

In order to achieve the above object, in this invention, a pipette device that aspirates a required amount of liquid at a predetermined position and discharges this liquid at another position is composed of a fixed outer cylinder and this fixed outer cylinder. It is characterized by comprising an inner cylinder housed in the body and movable up and down, and configured so that cleaning water is supplied to the gap between the inner cylinder body and the fixed outer cylinder body. be.

[Effect]

Therefore, in the pipette device according to this invention, in order to prevent the pipette from being bent by the rubber stopper, the fixed outer cylinder is first lowered and the inner cylinder is passed through the rubber stopper. The hole is opened, and the inner cylindrical body is then lowered to suck up the liquid in the container, and the liquid level is detected when the tips of both cylindrical bodies are immersed in the liquid. This feature is characterized in that it is configured to make a determination based on the following information.

〔Example〕

This invention will be described in detail below based on an embodiment shown in the accompanying drawings.

As shown in FIG. 1, the pipetting device 10 according to this embodiment includes a fixed outer barrel 12 fixed to one end of an arm 11, and a drive device 13 housed within the fixed outer barrel 12 to be described later. Therefore, the inner cylindrical body 1 which is moved up and down in the vertical direction in FIG. 1 and acts as a pipette
4, a rotary drive device 16 for rotating the arm 11 around the shaft 15 from a liquid suction position to a liquid discharge position and a cleaning position (none of which are shown) at a predetermined timing; Vertical drive device 1 for raising and lowering the inner cylindrical body 14
7, means 18 for detecting the contact state between the lower end of the fixed outer cylinder 12 and the liquid, means 19 for detecting the contact state between the lower end of the inner cylinder 14 and the liquid, and each of these liquid levels. Based on the information from the contact detection means 18 and 19, in addition to the drive device 13, the rotation drive device 1
6 and the vertical drive device 17, and the cleaning water 2 is placed in the gap 20 formed between the inner circumferential surface of the fixed outer cylinder 12 and the inner cylinder 14.
1, and a cleaning device 22 that supplies 1.

The fixed outer cylinder 12 is shaped like a large-diameter injection needle, and its lower end is inclined diagonally so that it can be easily inserted into a rubber stopper 24 attached to a container 23. It is configured.

On the other hand, the inner cylindrical body 14 is configured in the shape of a small-diameter injection needle, and is arranged so as to be movable up and down inside the fixed outer cylindrical body 12 along its axial direction x.
Of course, the inner cylindrical body 14 is formed longer than the fixed outer cylindrical body 12.

The drive device 13 that moves the inner cylindrical body 14 configured in this manner up and down along the axial direction x includes a gear 25 attached to the upper end of the inner cylindrical body 14.
a rack and pinion 26 that meshes with the rack and pinion 26, and a motor 27 that rotates the rack and pinion 26.
The motor 27 is controlled by the control device CPU to rotate in accordance with the descending distance of the inner cylindrical body 14. Incidentally, the reference numeral 28 in the figure indicates a pump connected in communication with the inner cylinder body 14.

In addition to drive control of the drive device 13, the control device CPU also controls drive of a rotary drive device 16 that moves the arm 11 from a liquid suction position to a liquid discharge position and a cleaning position (none of which are shown); A vertical drive device 17 that raises and lowers the inner cylindrical body 14 at each of the positions is controlled.

Furthermore, the control device CPU obtains liquid level information detected by the fixed outer cylinder 12 and the inner cylinder 14 from the detection means 18, 19, and based on this information, the control device CPU obtains the liquid level information detected by the fixed outer cylinder 12 and the inner cylinder 14, By controlling the drive, the drive is controlled so that accurate liquid weighing work is performed.

Next, the operation of the pipette device 10 having the above structure will be explained.

When the container 23 with the rubber stopper 24 attached thereto is set at a predetermined position, the control device CPU controls the rotary drive device 16 to rotate the fixed outer cylinder 12.
Then, the inner cylinder 14 housed in the fixed outer cylinder 12 (as shown by the imaginary line in FIG. 1) is transferred to the set position.

Next, the control device CPU controls the vertical drive device 17.
is controlled to move the fixed outer cylindrical body 12 and the inner cylindrical body 14 downward toward the container.

As a result, the fixed outer cylinder 12 is attached to the rubber stopper 24.
When the lower end passes through the rubber stopper 24, the drive device 13 starts driving the inner cylinder 14, and moves the inner cylinder 14 to a position where it protrudes a predetermined distance below the lower end of the fixed outer cylinder 12. (a depth corresponding to the amount of liquid to be sucked by the inner cylinder 14).

In this way, the inner cylindrical body 14 is connected to the fixed outer cylindrical body 1.
2, the vertical drive device 17 further lowers the fixed outer cylinder 12 and the inner cylinder 14, and the control device CPU moves the fixed outer cylinder 12 and the inner cylinder 14 downward. The operation of the vertical drive device 17 is stopped when both lower end portions of the vertical drive device 14 come into contact with the liquid.

After the lower ends of the fixed outer cylindrical body 12 and the inner cylindrical body 14 are immersed in the liquid in this way, the pump 28 starts operating and the liquid in the container 23 is sucked, and the suction operation is performed. When this is completed, the vertical drive device 17 starts operating again to raise the fixed outer cylindrical body 12 and the inner cylindrical body 14, and remove these cylindrical bodies 12 and 14 from the rubber stopper 24.

Thereafter, the fixed outer cylinder 12 and the inner cylinder 14 are transferred to a cleaning position (not shown) by the rotary drive device 16, and in this cleaning position, the cleaning device 22 cleans the inner circumferential surface of the fixed outer cylinder 12. A cleaning operation is performed by supplying cleaning water 21 to the gap 20 between the outer circumferential surface of the inner cylindrical body 14 and the inner cylindrical body 14 . As a result, the inner circumferential surface of the fixed outer cylinder 12 and the outer circumferential surface of the inner cylinder 14 are thoroughly cleaned.
Cross contamination is prevented.

Thereafter, the above operation is repeated.

In the above embodiment, the rack-and-pinion 26 is used as the means for lowering the inner cylinder 14, but the present invention is not limited to this. For example, a worm gear may be used. A mechanism using a mechanism, or a known linear drive means consisting of a pulley and a wire, etc. can be applied.

[Effect of idea]

As explained above, in this design, the fixed outer barrel first descends to open a hole in the rubber stopper through which the inner barrel passes, and then the inner barrel descends to fill the liquid inside the container. Since the structure is configured to aspirate liquid, there is no need to remove the rubber stopper from the container each time when aspirating liquid with a pipette.As a result, it is possible to eliminate concerns about infection during tests for AIDS, etc., and the pipette is There is no problem of bending or damage due to the rubber stopper, and since the liquid level is detected by detecting the point at which the tips of both cylinders are immersed in the liquid, it is possible to manage the accuracy of liquid suction. It has excellent effects such as being extremely easy to use.

[Brief explanation of drawings]

FIG. 1 is an explanatory cross-sectional view showing the structure of a pipette device according to an embodiment of this invention. Explanation of symbols, 10... Pipette device, 12...
Fixed outer cylindrical body, 13... Drive device, 14... Inner cylindrical body, 20... Gap portion, 22... Cleaning device.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A pipette device that aspirates a required amount of liquid at a predetermined position and discharges the liquid at another position is provided with a fixed outer cylinder and a pipette device that is housed within the fixed outer cylinder. 1. A pipette device comprising: an inner cylinder that is movable up and down; washing water is supplied to the gap between the inner cylinder and the fixed outer cylinder. (2) The pipetting device according to claim 1, wherein the inner cylinder and the fixed outer cylinder are electrodes for detecting the liquid level.