JPH0441321Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to an improved structure of a sampling valve that functions to quantify and transfer a liquid sample in an automatic analyzer.

[Conventional technology]

In automatic analyzers, a valve called a sampling valve has conventionally been used to quantify and transfer a liquid sample.

This sampling valve is composed of fixed valves 1, 1 and a rotary valve 2, as shown in FIG. 2, and operates as described below.

First, in the state shown in FIG. 2a, the through hole 31 provided in the rotary valve 2 is connected to the through holes 32a, 32a provided in the fixed valves 1,1. At this time, when the piston of the suction cylinder 26 is lowered, the sample 24 in the container 23 is
The liquid is sucked into the suction cylinder 26 through the through holes 32a, 31, 32a and the flow path 25. At this time, the through hole 31 in the rotary valve 2 is filled with a certain amount of sample.

Next, when rotating the rotary valve 2 by a certain angle,
The through hole 31 in the rotary valve 2 is connected to the fixed valves 1, 1.
It connects to other through holes 32b, 32b provided therein.

Thereafter, when the piston of the fixing cylinder 30 is lowered as shown in FIG.
It is pushed out into the container 29 through the through holes 32b, 31, 32b and the flow path 28. At the same time, a certain amount of the sample filled in the through hole 31 is also pushed out into the container 29. As a result, container 2
9, a diluted sample with a predetermined concentration is prepared.

In this way, the sampling valve is used to quantify a certain amount of sample and dilute it with a certain amount of diluent to create a diluted sample.

[Problem that the invention attempts to solve]

As mentioned above, in the sampling valve,
Since the rotary valve 2 is rotated with a certain amount of sample filled in the through hole 31, the surface where the fixed valve 1 and the rotary valve 2 are in contact and rub together (hereinafter referred to as the sliding surface) is , ideally should have a very smooth mirror finish. This is because if there are scratches or irregularities on the sliding surface, liquid will leak from the outer periphery of the sliding surface, and the quantitative measurement of the sample filled in the through hole 31 will be disrupted.

However, if the sliding surface is too well finished, the fixed valve 1 and the rotary valve 2 will come into close contact with each other, and there will be no moisture on the sliding surface, and the rotary valve 2 may not rotate. (Hereinafter, this phenomenon will be referred to as fixation).

Therefore, in practice, the finish of the sliding surface is made rough to some extent so that moisture can be present on the sliding surface.
This allows the rotary valve to rotate easily.

On the other hand, although moisture is constantly evaporating from the outer periphery of the sliding surface, a very small amount of liquid is supplied to the sliding surface when the rotary valve moves, so the sliding surface does not stick. Of course, the amount of liquid that wets the sliding surface is extremely small and does not affect the accuracy of quantitative determination of the liquid filled in the through hole 31.

However, if the above-mentioned sampling valve is not operated for a long period of time, no liquid is supplied to the sliding surfaces and the moisture evaporates, causing the remaining components in the liquid to harden and remain, resulting in the problem of the sliding surfaces sticking.

This invention was made in order to solve the above-mentioned problems, and provides a sampling valve that does not stick even if it is not operated for a long period of time.

〔Example〕

The structure and operation of this invention will be explained based on an embodiment shown in FIG.

The sampling valve of this invention consists of fixed valves 1, 1, a rotary valve 2 sandwiched between them, a flange 4 fitted with a key (not shown) for fixing the fixed valves 1, 1, and a fixed valve 1. ，
1 and the rotary valve 2 between them and the flange 4, and a drive shaft 12 that passes through the fixed valves 1, 1, the rotary valve 2, and the flange 4 on a concentric axis. The conventional sampling valve is characterized by being equipped with a liquid chamber 10 that covers the outer periphery of the sliding surfaces 14 of the fixed valves 1, 1 and the rotary valve 2.

Note that the rotary valve 2 is fixed to the drive shaft 12 by a key (not shown) provided on the drive shaft 12, and rotates together with the drive shaft 12. The drive shaft 12 is an external drive source (not shown) for the sampling valve.
connected to and driven by. Further, the entire sampling valve is fixed to the main body of the automatic analyzer via the flange 4.

In this embodiment, a step is provided on the side of the fixed valves 1, 1 that contact the rotary valve, and the small diameter portions 1a,
1a is provided. The diameter of the small diameter portions 1a, 1a is made smaller than the outer diameter of the fixed valves 1, 1.
The outer diameter of the rotary valve 2 is made smaller than the diameter of the small diameter portions 1a, 1a.

The cylinder 3 is sandwiched between the fixed valves 1, 1, and is assembled so that its cut surface is in contact with the stepped portion of the fixed valves 1, 1. Nipple joints 8 and 9 are attached to the cylinder 3 by screw connection. Further, in order to seal liquid inside the cylinder 3, the nipple joints 8, 9 are covered with caps 5, 5.

The liquid chamber 10 is formed by the cylinder 3, the fixed valves 1, 1, and the rotary valve 2, and is arranged between the fixed valves 1, 1 and the cylinder 3 to prevent the liquid sealed in the liquid chamber 10 from leaking. O-rings 7, 7 are fitted into the. The inner peripheral surface of the cylinder 13 is provided with a semicircular groove for holding an O-ring.

In this way, the sliding surface 1 of the sampling valve
If the outer circumferential portions of sampling valves 4 and 14 are always covered with liquid, the moisture on sampling valve sliding surfaces 14 and 14 will evaporate and the sliding surfaces 14 and 14 will not dry and become stuck.

In addition, the nipple joints 8 and 9 are made of transparent material,
It is also possible to make it possible to check the amount of the sealed liquid from the outside.

In this embodiment, a cap 5 is attached to seal the liquid in the liquid chamber 10, but instead of this cap 5, a drain pipe of an automatic analyzer is connected to the nipple joints 8, 9, for example, a nipple Fitting 8
may be used as an inlet, and the nipple joint 9 may be used as an outlet. In this way, the liquid chamber 10
Liquid is automatically supplied into the chamber when the automatic analyzer operates.

[Effect of idea]

By implementing this idea, it has become possible to keep the outer periphery of the sliding surface of the sampling valve always covered with liquid. Therefore, even if the sampling valve is not operated for a long period of time, there is no possibility that moisture evaporates, the sliding surface dries, and the sampling valve becomes stuck, which is a remarkable effect in practical use.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional assembly view of essential parts showing an embodiment of this invention, and FIG. 2 is an explanatory diagram showing the operation of a conventional example. 1, 1... Fixed valve, 2... Rotating valve, 3
...Cylinder, 4...Liquid chamber.

Claims (1)

[Claims for Utility Model Registration] (1) A fixed valve having a plurality of through holes, and one or more fixed volume valves that are in surface contact with one end surface of the fixed valve, are arranged on a concentric axis with the fixed valve, and have a fixed volume. In a sampling valve for an automatic analyzer consisting of a rotary valve with a through hole,
A structure for preventing sticking of a sampling valve, characterized by providing a liquid chamber that covers the outer periphery of a sliding surface where a fixed valve and a rotary valve come into contact. (2) Sampling characterized in that the liquid chamber described in paragraph (1) of the utility model registration request is provided with an inlet and an outlet, and a drain pipe through which the discharged liquid of the automatic analyzer flows is connected to the inlet. Valve sticking prevention structure.