JPH06265448A - Liquid supply system - Google Patents

Abstract

(57) [Abstract] [Purpose] To prevent contamination of nozzles by dust in the room and improve analysis accuracy. A liquid supply device in which a nozzle 1 movable to an arbitrary position and an arm 2 holding the nozzle 1 are provided so that a nozzle cover 3 covering the periphery of the nozzle 1 can be moved up and down. [Effect] Contamination due to dust in the room adhering to the nozzle is prevented, and analysis accuracy is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid supply device for an atomic absorption photometer, liquid chromatography and the like.

[0002]

2. Description of the Related Art Generally, physics and chemistry equipment such as an atomic absorption spectrophotometer and liquid chromatography are installed and used in a laboratory or the like. Since these laboratories are often not clean rooms, dust or the like exists in the rooms.

As a device for dispensing a sample liquid to be measured, for example, a device described in Japanese Patent Publication No. 50-9314 is known. This device uses a pipette to prevent the outer surface of the movable nozzle that sucks the target liquid and discharges the target liquid to the addition position from being contaminated with the previously sucked and discharged solution. The liquid for cleaning the movable nozzle can be discharged from the pipette. The pipette is connected to a liquid injecting device for discharging a liquid by a flow path, and during suction and discharge of the target liquid, the pipette does not move up and down, only the movable nozzle moves up and down, The movable nozzle is exposed to the outside air.

[0004]

However, in the conventional device, the contamination of the movable nozzle by the sucked and ejected target liquid is eliminated by flowing the liquid for cleaning through the pipette on the outer periphery, but it is against dust and the like in the room. No consideration was given.
Since the position of the pipette is fixed, the movable nozzle is exposed to the outside air during the suction and discharge of the target liquid and is contaminated with dust and the like, and there is a problem that the analysis accuracy is deteriorated due to the nozzle contamination.

An object of the present invention is to provide a liquid supply apparatus which prevents dust and the like in the outside air from adhering to the movable nozzle in normal times and allows only the movable nozzle to enter the target liquid when necessary.

[0006]

In order to achieve the above object, the present invention has a protective cover attached to the outer periphery of a movable nozzle, and the protective cover serves as a movement limiting member when sucking and discharging a target liquid. It is fixed in contact with the movable nozzle, and by moving only the movable nozzle to a position below the movement restricting member, the movable nozzle can be prevented from being contaminated by dust or the like in the room.

[0007]

A protective cover is provided on the outer periphery of the nozzle of the liquid supply device to constantly protect the nozzle from dust and the like in the outside air, and when sucking and discharging the target liquid, the movement restricting member blocks the nozzle from the outside air. Therefore, dust in the laboratory does not adhere to the nozzle surface and contaminate the target liquid, and as a result,
Improve analysis accuracy.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

The liquid supply apparatus is composed of a nozzle 1, an arm 2 for holding the nozzle 1, and a nozzle cover 3 for the purpose of preventing dust and the like from adhering to the nozzle 1.

The nozzle cover 3 has a spring 4 fixed to the upper portion thereof, and as shown in FIG. 4, has a hollow column 10 having a size in which the nozzle 1 can move. Further, the other side of the spring 4 which is not fixed to the nozzle cover 3 is fixed and attached to the arm 2. In the state of FIG. 1, the nozzle cover 3 has a length that covers the nozzle 1 to the tip and does not contact the sample cover 5 when the nozzle 1 moves in parallel.

As shown in FIG. 2, in the liquid supply device, the nozzle 1 moves up and down to suck or discharge the target liquid 7. In this embodiment, as shown in FIG. 2, when sucking the target liquid 7, first, the nozzle 1 is moved in parallel onto the target liquid 7,
Next, the target liquid 7 is sucked to move downward. At this time, as shown in FIG. 2, since the lower portion of the nozzle cover 3 that moves downward together with the nozzle 1 contacts the sample cover 5,
The downward movement of the nozzle cover 3 is prevented. That is, the sample cover 5 serves as a movement restricting member to prevent the nozzle cover 3 from lowering any further. On the other hand, the nozzle 1 continues to descend to a certain position in the sample cup 6 together with the arm 2 by utilizing the expansion and contraction motion of the spring 4 fixed to the upper portion of the nozzle cover 3, and sucks the target liquid 7. After sucking the target liquid 7, the nozzle 1 moves up to the original position together with the arm 2. At this time, the nozzle cover 3 separates from the sample cover 5, and as shown in FIG.
To the tip, and move in parallel to the addition position where the aspirated sample is discharged.

FIG. 3 illustrates the liquid discharge state of this apparatus.
After moving the nozzle 1 to the addition position such as the cuvette 8,
The sucked target liquid 7 is discharged. The target liquid 7 operates in the same manner as during suction, but in this case, the atomization part lid 9 serves as a movement limiting member of the nozzle cover 3.

The nozzle cover 3 is, as shown in FIG.
Make sure that the nozzle 1 has a length that covers the target liquid 7 to the tip,
In addition, as shown in FIG. 2, when the nozzle 1 moves downward, the length is shorter than the distance a between the arm 2 and the movement restricting member such as the atomization part lid 9. Also, the spring 4 is
As shown in FIG. 2, in a contracted state, the size is set so that the arm 2 and the nozzle cover 3 can comfortably fit within the distance b.

The liquid supply apparatus first moves the nozzle 1 downward to suck the sample, then moves upward to return to the state of FIG. 1 and then moves in parallel, and again moves downward to discharge the sample. During the parallel movement and the downward movement, if the nozzle cover 3 is attached, it is possible to prevent dust and the like from adhering to the nozzle 1. As a result, it is possible to prevent a decrease in analysis accuracy when it is considered that the nozzle 1 is contaminated.

[0015]

The present invention is designed to prevent dust and the like in the air from adhering to the nozzle when the target liquid is sucked and discharged, so that it is possible to prevent deterioration of analysis accuracy due to contamination.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a configuration of the present invention.

FIG. 2 is a diagram illustrating an operation during liquid suction.

FIG. 3 is a diagram illustrating an example of a liquid ejection state.

FIG. 4 is a view showing a plane and a cross section of a nozzle cover.

[Explanation of symbols]

1 ... Nozzle, 2 ... Arm, 3 ... Nozzle cover, 4 ... Spring, 5 ... Sample cover, 6 ... Sample cup, 7
... object liquid, 8 ... cuvette, 9 ... atomization part lid, 10 ... hollow pillar above nozzle cover, a ... distance between arm and movement limiting member, b ... distance between arm and nozzle cover.

Claims (7)

[Claims] 1. Inhaling a target liquid from a container at an inhalation position,
In a liquid supply device including a movable nozzle that discharges the sucked target liquid at the addition position and a holding member that holds the movable nozzle, a protective cover that covers the periphery of the movable nozzle can be moved up and down. Provided on the holding member,
A movement restricting member is arranged above the container at the suction or discharge position, and when the holding member descends at the suction or discharge position, the protective cover prevents the descending movement by the movement restricting member. However, the liquid supply device is characterized in that the movable nozzle is configured to advance below the movement restricting member. 2. The liquid supply apparatus according to claim 1, wherein the protective cover is arranged on the holding member by an expandable and contractible installation member such as a spring and can move up and down. 3. The protective cover and the movement restricting member according to claim 1, wherein when the sample is sucked in and discharged, the protective cover comes into contact with the movement restricting member to shield the movable nozzle from the outside air. Liquid supply device. 4. The protective cover and the movement restricting member according to claim 1, wherein the movable nozzle is housed in the protective cover during normal operation. The liquid supply device is characterized in that it has an effect of preventing the movable nozzle from being contaminated because it is shut off from the liquid supply device. 5. A liquid supply device characterized in that a flame-retardant plastic or the like is adopted for the protective cover according to claim 1. 6. The movement restricting member according to claim 1 or 3, wherein a new member is disposed above a position where liquid is sucked in or discharged, or a part of a liquid supply device main body such as a sample cover is used. A liquid supply device characterized by: 7. The protective cover according to claim 1 is of such a length that it fits between a holding member and a movement restricting member when sucking or discharging a liquid, and does not interfere with sucking or discharging the liquid of a movable nozzle. A liquid supply device characterized by the above.