PROCEDE ET INSTALLATION DE DILUTION AUTOMATIQUE

Process and device for the automatic dilution of solutions using a peristaltic pump. Successive dilution processes can be carried out with a relative precision that remains high for a long time and without manual interference, with the advantage that the device is easily adjustable to any desired degrees of dilution. The peristaltic pump rotates continuously at a constant rate in one direction and the suction line immerses alternately, in each case during a certain number of pump strokes, in the solution to be diluted and in a diluent. A dilution operation is comprised of three stages, in which the suction tube is immersed in the diluent in the first and last stages and in the solutions to be diluted in the middle stage. The pump is comprised of a sensor for monitoring the temporal sequence of the contact of the pump cylinders with the feed tube in order to emit an appropriate output signal, a device for moving the suction line into the two immersion positions in separate locations, and a control unit for controlling the moving device synchronously with the sensor signals.