Erythrocyte sedimentation automatic measuring appts. - has blood samples in parallel tubes each enclosed by movable photoelectric fork

• Main Author: PIERRE BRUN ET YVES PAWLOTSKY
• Format: Patent
• Language: English; French
• Published: 16.12.1983
• Subjects: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; TESTING

The appts. has a support comprised of a base, an upright and a bracket which hold, in parallel, a number of calibrated capillary tubes. EAch tube contains a sample of blood under a porous cap. Each tube is surrounded by a photoelectric fork which is mounted on a single bar translationally displaceable along the tubes by means of an endless screw, the position of the bar being measured by an angular pick-up. One part of each fork is an electroluminescent diode which emits a narrow beam of electromagnetic radiation at wavelength in the region of 9,500 angstrom. Pref. the radiation is modulated at a frequency of Kilohertz order, the diameter of the beam being of millimeter order. The other part of the fork is a photodetector, such as a silicon photodiode or phototransistor sensitive to radiation of this wavelength. The height of the blood-plasma separation surface is measured in each tube relative to the porous cap as a function of the signal received by each photodetector. The signal presents a sharp maximum in the presence of plasma between the two elements of each fork. The height measurement may be repeated at chosen time intervals following the sedimentation level curve in order to obtain information on the speed of sedimentation. DES ECHANTILLONS SANGUINS DONT L'HEMATOCRITE A ETE NORMALISEE SONT PLACES DANS DES TUBES CAPILLAIRES (TA A TL). UNE BARRE21 PORTE UNE PLURALITE DE FOURCHES PHOTOELECTRIQUES (101, 102: 111, 112,ETC.) DONT CHACUNE ENCADRE L'UN DES TUBES. TRAVAILLANT DANS L'INFRAROUGE MODULE A 5KHZ, CES FOURCHES PHOTOELECTRIQUES PERMETTENT LA DETECTION DE LA HAUTEUR DE PLASMA, ET PAR LA LA MESURE DE LA VITESSE DE SEDIMENTATION. A CET EFFET, LA BARRE21 EST DEPLACEE EN TRANSLATION VERTICALE, PAR EXEMPLE SOUS L'EFFET D'UNE VIS SANS FIN25 MUE PAR UN MOTEUR28 ET ASSOCIEE A UN CODEUR ANGULAIRE29.