JPS6032135B2 - Measurement room unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a measuring chamber unit, more particularly to a measuring chamber unit in the form of a block, especially for use in electrochemical measuring instruments, forming one or more interconnected measuring chambers.

Electrochemical measuring instruments or devices are known which are suitable for carrying out a large number of different measurements simultaneously or successively in a corresponding number of measuring chambers, defined as a measuring chamber unit.

If a measuring device or instrument is to perform very precise measurements on very small volumes or liquids, very demanding demands must be made on the measuring chamber and the mutual access passages. Whether the fluid sample to be measured is a gas or a liquid (which can contain dissolved gases),
The internal surfaces forming the measurement chamber and the lotus passage must be of such a nature that they do not change the composition or properties of the fluid sample to any essential degree when the sample is passed through the measurement chamber unit. Changes in the composition of the fluid sample can be caused by contamination by substances left in the measuring chamber under previous measuring steps, by absorption of gas into the fluid sample from the measuring chamber walls, or by gases escaping from the fluid sample by the measuring wall. It may also be caused by absorption. For the reasons mentioned above, it is desirable for the measuring chamber unit in question to be made of a material with a high surface density and inert towards the fluid sample, for example stainless steel or glass. However, when these materials are used, it is necessary to grind or polish the surfaces of the measuring chamber and connecting channels.
Since the measurement chamber as well as the internal communication passages are usually of very small dimensions and relatively complex shapes, it is relatively expensive to manufacture the measurement chamber unit from materials such as glass or stainless steel. Introducing the fluid sample into the measuring chamber unit may change the composition of the sample (to the extent that the resulting measurement errors must be compensated for if possible), but in order to reduce costs it is It has been found that it is necessary to form the measuring chamber unit from plastic. British Patent No. 134
No. 6533 discloses a measurement chamber unit having a measurement chamber formed by a number of recesses or depressions having a common space formed on one side of a block shape,
Adjacent recesses are communicated by V-shaped connections. The present invention provides a measurement chamber unit of the above type that is simple to manufacture and easy to finish to obtain the desired surface characteristics of the lotus channel surface as well as the measurement chamber surface.

The invention also relates to a block-shaped measuring chamber unit, particularly for use in electrochemical measurements, having two opposing surfaces, in which an outwardly closing recess or recess is formed. , wherein said unit has a plurality of straight passages or holes extending therethrough, each straight passage or hole communicating with a recess or depression on one side of the opposing surface and a recess or depression on the pond side; provide.

Measuring chamber units of this type can be manufactured relatively easily from a block-shaped body of a material with suitable properties, such as glass or stainless steel. Thus, the recesses or depressions in the opposite surfaces may also be produced by milling, grinding or other suitable machines, and a straight line extending through the block-shaped body between the recesses or depressions in the two opposite surfaces. Each of the shaped connecting passages or holes can also be produced by a simple drilling operation. Since the measurement chamber unit according to the present invention has a simple shape, the surfaces of its recesses and lotus holes can be relatively easily ground, polished, or otherwise given a desired finish. Furthermore,
By arranging the measurement chamber recesses on the opposite side of the flock shape, it is possible to obtain a measuring device with a more compact structure than when all the measurement chambers are arranged on the same side. And because the channels or holes extending between the measuring chambers are straight, their cleaning is easier, so it is essential to avoid contaminating the sample to be measured with substances originating from the previous sample. It is possible.
The recesses in the flock-shaped body are interconnected, for example, with recesses in the opposite surface of the block, with a corresponding number of three or more channels extending from the centrally located recess.

However, according to the invention, "the recesses in the opposite surfaces of the block-shaped body are preferably connected in series by straight holes or passages, in which case the recesses and the lotus passages or holes together extend over the entire length." According to the invention, each pair of successively running recesses is formed and arranged in alternating opposite surfaces, and the peripheral area of the recesses is According to such an embodiment, it is also possible to obtain a measurement channel without sudden changes in course, and the circumference of the recess, i.e., the rim portion Because the intercommunication path is open in the measurement path, it is possible to obtain an effective flow pattern without forming "pockets" as the fluid sample passes through the measurement path. By arranging the recesses or measuring chambers as described above, good mutual positioning of the measuring instruments installed in the measuring chambers is possible. Of course, the recess or depression serving as the measuring chamber must be closed in one way or another.

Conveniently, this is done by a measuring device installed in each single measuring chamber. This measuring device can be, for example, an electrochemical measuring electrode of the type with a semipermeable membrane at one end. The measuring electrode is mounted continuously on the block-shaped body, if possible using a sealing ring or other suitable sealing element, so that the measuring electrode end with the membrane faces the recess and seals it from the outside. may be done. In order to make accurate measurements, it is necessary to ensure that the fluid sample being measured is maintained at a predetermined temperature. It is therefore necessary to heat or remove heat from the fluid sample in the measurement chamber unit, and for this reason it is desirable to manufacture the block-shaped body from a material with good heat conduction properties. This requirement is met by stainless steel and other metals, but some measurements can introduce errors if the measuring chamber is made of conductive material, so in practice glass or plastics are increasingly being used. There is. The first of these materials has a number of good properties, but is relatively difficult to machine and finish, while the last material is easy to shape but has an undesirable finish as described above. have characteristics. Plastics also have relatively poor thermal conductivity. According to the invention, the block-shaped body is therefore advantageously manufactured from glass-ceramic. This material, which is effective in block shapes and has very good machinability, was shown to have other properties necessary to produce measuring chamber units of the type in question, at least comparable to glass. . According to another aspect, the invention therefore provides a method for manufacturing a measurement chamber unit of the above type.

This method involves machining a plurality of recesses or indentations in oppositely facing surfaces of a block-shaped body, each drilling a straight passageway into the body extending between two recesses formed in the surface. It is. Furthermore, the present invention relates to measuring chamber units of all shapes for use in electrochemical measuring instruments,
An instrument, in particular for the measurement of very small quantities of blood or other body fluids, consisting of a measuring chamber unit made at least partially of glass-ceramic.

In this specification, the term "block-shaped body" includes not only parallelepipeds, but also bodies having two oppositely facing flat or curved sections with sufficient space to form the recesses or depressions mentioned above. .

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail below with reference to a sectional view of a measurement chamber unit that is an embodiment thereof.

In the drawing, the measuring chamber unit is constructed from a block 10 of a suitable metal such as glass-stainless steel or other preferred material, but may be made of glass-ceramic, such as MACOR (trade name: Corning Glass Works). , New York, USA
Corning Co., Ltd.) is preferred. The flock 1 has two opposite sides 11, 12 in which a plurality (three in the drawing) of depressions or depressions 13 are formed. These recesses 13 are provided alternately in the longitudinal direction of the block 10, and obliquely extending passages or holes 14 (
The holes 15 extend from the recesses adjacent the end faces 16 and open into these end faces. A number of measuring instruments or measuring electrodes 17, 18 and 19 are located in a close sealing manner from the outside in corresponding parts of the recess 13, thereby forming a measuring chamber therein.

As clearly shown in the drawing, the measurement chamber formed by the recess 13 is continuous with the holes 14 and 15 and forms a slightly zigzag-shaped measurement path. Measuring electrodes 17-19
is secured against the block 0' by suitable means (not shown), and the necessary sealing between the electrode and the adjacent surface of the block 10 can be obtained by means of a sealing ring 20, such as an 0-ring. These two seal rings are simultaneously used to hold the semipermeable membrane 21 covering the electrode tip. The disclosed measurement chamber unit can also be used in automated measurement equipment of the semi-automatic type, such as that disclosed in US Pat. No. 3,874,850.

When the measuring chamber unit is included in a blood sample measuring device, the measuring electrodes 17, 18 and 19 are for example C02
It may be used to measure each of partial pressure and 02 partial pressure.

Such measuring electrodes are known in the art, and therefore the measuring electrodes are not shown in detail in the drawings. It should be understood that various changes and modifications may be made to the embodiments illustrated in the drawings without departing from the scope of the invention.

Therefore, it is not necessary for each block to have a parallelepiped shape, and for example, it can also have a cylindrical shape. The recesses can also be formed in essentially opposite portions of the cylindrical surface.
It should also be appreciated that not all of the recesses 13 need to be formed along one or the same plane. Therefore, these recesses can not only be provided longitudinally at different angles, but also be arranged laterally to each other. Although, as shown in the drawings, the measuring chamber is advantageously formed in the recess 13 by means of measuring devices or measuring electrodes, the measuring chamber may be formed in other ways, e.g. by plates or devices mounted on the sides 11 and 12 of the block 10. or by attaching a measuring device. As mentioned above, glass-ceramics are of surprising value in the context of measuring chambers of the above type, especially for use in measuring blood and other body fluids. The invention is therefore also constructed by using glass-ceramic materials for such measuring chambers, irrespective of their structure and shape.

[Brief explanation of the drawing]

The drawing is a sectional view showing one embodiment of a measurement chamber unit according to the present invention. 10...Flock, 13...Concavity, 1
4, 15... Passage 17, 18, 19...
...Measurement electrode.

Claims (1)

Claims: 1. at least one outwardly opening recess forming a measuring chamber in each of the oppositely facing surfaces, and one or more straight passages extending obliquely inward with respect to the surface; A measurement chamber unit characterized in that it is a block-shaped electrochemical measurement chamber unit in which a recess on one side and at least one recess on the other side communicate with each other. 2. A unit according to claim 1, wherein the unit at least partially consists of glass-ceramic. 3. The unit according to 2 above, wherein the recesses are continuously connected by a passage. 4. The unit according to item 3, wherein the recesses on one side of the surface portion are arranged in a staggered manner with the recesses on the other side, and each connecting passage opens into the peripheral area of the recessed portion that forms an acute angle with each surface portion and communicates therewith. 5. The unit according to claim 1, wherein the unit is made of glass-ceramic and has two or more outwardly opening recesses in its surface, which recesses are communicated by one or more passages in the block.