Abstract: This invention relates to a method and an equipment for portioning of liquid consignments of specific amounts and to the packaging of these small liquid consignments in mass production. The portioning is executed with a bellows, which defines an air space of varying volume, that the air stream caused by the bellows establishes the injection and suction of a liquid. According to the invention the air space is connected to the suction tip (4), which holds a liquid space confined by a filter permeable to air stream but impermeable to liquid. When in the suction phase the liquid is sucked into the suction tip (4) by the motion of the liquid, and in the injection phase the reverse motion of the bellows is used in injecting the liquid consignment from the suction tip, and the injection of the liquid consignment of certain volume is based on a corresponding volume change in the air space of the bellows established by an equipment controlling the bellows.

Abstract: The invention relates to a method and equipment for quantitatively dosing small amounts of liquid, especially in clinical or other similar wet-chemical analyzers. The dosing employs a liquid space, the volume of which can be changed and which is connected to a dosing channel so that, by increasing or decreasing the volume of the liquid space, a suction or an injection through the dosing channel is achieved. The liquid space is formed by flexible bellows which are freely movable back and forth to provide the reversible deformations which change the volume of the liquid space. The movements are effected using an actuator which is connected to the bellows without transmissions containing sliding surfaces. The actuator comprises precisely repeatable positions and is calibrated according to the invention by measuring the sizes of the dosages produced by the movements between the positions. The dosing is effected after that by selectively repealing the calibrated movements.

Abstract: The invention concerns a filtering unit comprising a filter diaphragm (11), a backing surface (12) disposed against the diaphragm, and passages through which the liquid to be filtered can be supplied on one side of the diaphragm and the liquid that has drained through the diaphragm can be removed from the opposite side of the diaphragm. As taught by the invention, the backing surface (12) is provided with ridges (13) lying side by side and with grooves (14), moving liquid in the direction parallel to the diaphragm (11), between them and which start in the central part of the surface in different directions and lead to the periphery of the surface, curving in such manner that the spacing of mutually adjacent ridges is substantially constant on the entire area of the backing surface. The backing surface (12) will then to the filter diaphragm (11) lend throughout uniform support.

Abstract: The invention concerns a procedure for forming cocks closable by freezing, belonging to a liquid batch handling unit, and a liquid handling unit set up in accordance with the procedure. The unit consists of two bodies (1,2) placed against each other, the cocks being located between their faces and one of them (2) comprising the flow passages leading to the cock points and the other body (1), which is connected to a refrigerator, being provided with electric heaters located at the cock points and with the aid of which the cocks can be opened and closed.

Abstract: The invention concerns a centrifuge intended for use in mainpulating liquid batches on an analytical scale. The centrifuge consists of a body (2) rotatable about its axis (1) provided with input and output conduits (8,9,11) and presenting the essential feature that therein are contained two parallel, circular arc-shaped volumes (3,4) located at different distances from the axis (1) of the body (2) constituting the center of curvature, and communicating with each other through a narrow gap (7) so that when the body is rotating, the heavier components of the liquid accumulate in the volume (4) further away from the axis, and the lighter components accumulate in the volume (3) closer to the axis, whereafter one of these two volumes can be emptied through a conduit (12), while the surface tension acting in the gap between the volumes keeps the liquid in the other volume in its place. The centrifuge of this invention is particularly appropriate for separating blood plasma from the red and white cells in the blood.

Abstract: The invention concerns a procedure for keeping and taking into use an analytic reagent or another substance used in analyses, and a reagent package to be used in the procedure. The package consists of a gas-tight sachet or of a combination consisting of several sachets, where the sachets comprises at least one flexible wall and a blank for forming a discharge aperture. The blank may consist of a hermetically sealed flexible tube extending into the interior of the sachet or a bar-like member with openings defined therein that extend into the sachets. The taking into use of the substance packed in the sachet is then accomplished by opening the flexible tube or the openings in the bar-like member and connecting the tube or the openings to the analyzer with an outward gas-tight connection. The substance is thereafter drawn from the sachet into said apparatus in one or several steps so that the sachet will collapse in connection with the discharge.

Abstract: The invention concerns an ion-selective electrode comprising a polymer membrane, and its manufacturing procedure. Selectivity of the electrode to a given ion has been achieved in that the membrane is of material polymerized from a substance or mixture of substances containing the ion in question and from which after the polymerizing step a quantity of ions of this kind has been removed so that gaps of equivalent size have been produced in the material. An example of said polymerizable substances is a mixture formed by allyloxy-substituted propyleneglycol phosphate and calciumbisdiallyl phosphate, which is used in making a calcium-selective electrode. If in the example mixture calcium is replaced by another ion, an electrode which is sensitive to this particular ion is similarly obtained. It is to advantage in view of the electrode's mechanical properties to make the electrode without internal solution by affixing the polymer membrane directly on the surface of a semiconductor body consisting e.g.