SU957044A1 - Device for feeding liquid samples - Google Patents

Abstract

Apparatus for moving a liquid sample through a measuring chamber (2) having an inlet duct thereto and an outlet duct therefrom, means (1) operable to close off said inlet and outlet ducts and a pair of pistons (5) operable on being moved to displace liquid in the inlet duct and outlet duct, said pistons (5) being connected together eg by rod 6 to operate in synchronism whereby a constant volume of liquid is maintained in the apparatus between the duct closing means on movement of the pistons which results in a corresponding movement of liquid through the measuring chamber (2) without turbulence. The apparatus preferably contains two electrode cells 3 for electrophoretic measuring. <IMAGE>

Description

(54) DEVICE FOR FEEDING LIQUID TESTS

one

The invention relates to devices for supplying liquid samples with little consumption and exclusion of turbulence in the measuring chamber with supply and discharge lines used for microscopic observation of dispersed particles in the measuring cell, for example, for electrophoresis measurements.

In the case of these measurements, many particles dispersed in the sample must be examined under the same measurement conditions for obtaining information. Due to the characteristic features of the measuring device, only a few particles are available in one sample location. In order to cover several particles, it is necessary to shift the sample to small values.

Devices are known in which the supply of samples is made by simultaneously opening or closing valves or taps.

The energy to move the sample is given by hydrostatic head. Other devices set the particles in motion by pumping fresh samples with pumps 1.

A disadvantage of the known devices is that the elements that cover

the system from the environment and to which the maximum requirements regarding tightness are imposed, are subject to maximum wear and thereby reduce the reliability that a fresh sample, which may have slightly different physical properties (temperature, pH value, conductivity), is fed into the measurement space and That reproducible offset by several .mikron impossible.

The invention makes it possible to carry out accurate measurements of a particular sample substance.

The purpose of the invention is to displace the sample material in the measuring chamber by a certain, very small distance in order to prevent the new sample material from entering the chamber and not to set in motion the means (valves, taps) to separate the measured from the rest of the trial material.

At the same time, in a measuring chamber, if possible, it is necessary to provide laminar flow conditions.

Claims (2)

This goal is achieved by the fact that in the device for supplying liquid samples to small values while avoiding turbulence in the measuring chamber with supply and discharge lines, which has means for a mechanical shutter of supply and discharge lines, from the side of the chamber from these means The supply and discharge lines are connected in one cylinder, these cylinders are parallel to each other, have the same internal diameter, contain one piston with the same diameter, which is rigidly connected to another piston, and the ends of the pistons in the opposite direction act on the test material. The movement of the pistons is realized if the piston is rigidly connected by a spindle in the direction of motion, which is in contact with the rotating nut. FIG. 1 shows a schematic of the first device; in fig. 2 is a schematic representation of a second device. The device comprises means 1 for shutting the supply and discharge lines, from the meridular chamber 2 (cuvette), two electrode chambers 3 for applying electrical voltage to the sample material, parallel cylinders 4, pistons 5 electrically insulated from each other, and a rigid connecting element 6 between these pistons, as well as elements 7 for sealing as compared with the wall of the cylinder. In the first device (Fig.), Each cylinder 4 is connected to the cuvette 2 through separate piping 8. At the rigid connecting element 6 between the pistons 5 on the support there is a handle 9 for actuating the pistons. In the second device (Fig. 2), the pistons 5 act on the sample material in extensions 0 of the supply and return lines. A rigid connection between the pistons 5 is realized through the spindle b as a connecting element which is in contact with the nut 11. By pressing the nut bearing 12 on the ball bearing 12, the test material is set in motion. Often, there are particularly high demands on the density of the vascular system. For this, the piston actuator can be completely sealed and set in motion with nut 11 provided with special cores using an external magnet 13. When the device is operated, the inlet and outlet pipelines are locked and the sample is moved in the system of vessels connected to the input and output of the measuring chamber by means of an oppositely directed, rigidly connected pair of pistons. Claim 1. Device for supplying liquid samples to the measuring chamber with inlet and outlet lines, characterized in that means are provided for mechanical shutter of the inlet and outlet lines, which from the chamber side from these means to the inlet and outlet the lines are connected in a single cylinder, that these cylinders are parallel to each other, have the same internal diameter, contain one piston each with the same diameter, which is rigidly connected to another piston, and that the ends of the pistons act on trial in the opposite direction. 2. A device according to claim 1, characterized in that the piston is rigidly connected to the spindle in the direction of motion, which is in contact with the rotating nut. It is recognized as an invention according to the results of the examination carried out by the Office for the Invention of the German Democratic Republic. ABOUT Fe / g. .  0t / g.2