AUTOMATIC INSTRUMENT OF BLOOD SEDIMENTATION RATE

摘要

PURPOSE:To examine and record automatically blood sedimentation rate, and thereby largely to reduce the working load of the examiner, by starting the examination with use of a timer, and detecting the boundary face between the plasma layer and the red cell layer or the cell layer with use of a photosensor moving along the side of a blood sedimentation rod. CONSTITUTION:Both an LED 16 which radiates an infrared ray, and a phototransistor 17 which receives the above ray and converts it into an electrical potential are attached to the edge of a round plate 10. A blood sedimentation rod 15 is put between the LED 16 and the phototransistor 17. Blood as a sample to be examined is put in the blood sedimentation rod 15. When a motor 1 rotates, a revolving rod 4 revolves in the positive direction, and the round plate 10 moves downward accordingly. This moving amount is proportional to the number of revolutions of the revolving rod 4, and the said number of revolutions is determined with the number of pulses which generate in direct proportion to the said number of revolutions, by means of a round plate 5 and a photosensor 6. Since the permeating amount of the infrared ray largely changes at the level where the LED 16 and the phototransistor 17 move from the plasma layer to the red cell layer, the boundary face between both layers is identified by watching the electric output of the phototransistor 17.