Patent DE-19749557-A1 (DE)
Title: Appts for parallel chemical reactions
Inventor: WIESMUELLER KARL-HEINZ
IPC: B01J19/00
Filed: 1997-11-10
Abstract: The appts. for a number of chemical reactions has at least one program-controlled robot (2) with a number of different function units (6,10,11,12,15,16,18,50,55) within its working range (4).  The robot has at least one moving arm (3) with at least one grip tool (17) and at least one dosing needle coupled to a dosing system to deliver dosed vols. of fluids.  The dosing needle is linked to the fluid supplies through at least one fluid feed line. A grip change system (16) has at least one and pref. several different grip tools (17) which can be fitted to the arm pref. without tools and automatically coupled in place. In use there is a single dosing needle, linked to a pump operated by suction and pressure.  A single flexible fluid feed line is between the pump and the needle, with pref. a magnetic switch valve near the dosing needle, and especially in the last one-tenth of the fluid feed line length. A solvent supply, under fluid or gas pressure, is linked to the fluid feed line, or through a second feed line also with a switch valve near the dosing needle.  The fluid feed lines are gathered together in a bundle of flexible lines. The valves are multiple valves, free of dead vols.  The valves are pref. mounted to a carrier which can be coupled to the arm (3) of the robot (2), automatically and without tools, in release fittings. A cleaning unit (55) is within the working range (4) of the robot, to wash the dosing needle, and a drying unit for the needle pref. especially using an inert gas and pref. nitrogen.  The pump and/or the pressurized solvent supply are part of the cleaning unit.  The dosing needle is inserted from above into the cleaning vessel (56), and the cleaning fluid is pumped through the needle into the vessel, to rise within the vessel and clean the exterior of the dosing needle. At least one of the functional units and especially a supply unit (6) and/or a resupply unit (18) is at or on a rotating table (5,18) which at least partially overlaps the working range (4) of the robot (2). At least one pref. optical immersion sensor detects the immersion of the dosing needle from an initial medium such as a gas into a liquid, at the end of the dosing needle with a light conductor at the free end. Light is carried from a lamp to the end of the conductor, with total reflection, to be coupled to a further light conductor to a light sensor.  The light is in the visible and/or infra red spectrum. A control system, using a perforated plate, registers the position and/or orientation and/or shape of the dosing needle.  The plate has a horizontal movement, on the movement of a sensor or switch, and has a hole matching the dosing needle size. A shut-off system to prevent damage and especially to the dosing needle and particularly by longitudinal pressure on it, is a pressure sensor or microswitch to monitor the longitudinal pressures on the needle. The appts. has at least one reactor unit (10), pref. more and especially10 reactor units (10) for a number of parallel chemical reactions.  Each reactor unit (10) has a number of pref. identical reaction vessels and especially 20 vessels, which can be filled from above by the dosing needle. At least one catch unit (50) takes the reaction products, linked to the reactor unit for them to flow out and be caught.  The catch unit (50) has a holder (9) for groups of pref. 10 catch vessels, each for a reaction vessel at the reactor unit. At least one weighing scales (11) weighs especially the reaction products and/or at least one vibrator (12) homogenizes the reaction products and/or at least one concentrator (15) clears the reaction products of volatile substances which can evaporate, and particularly liquid solvents.  The concentrator (15) is a rotary vacuum unit to handle several samples, and pref. 100 samples with a sample size of up to 10 ml. The vibrator (12) gives a simultaneous action on several samples, at least 10 samples and pref. 100 samples, especially with a sample size up to 10 ml.  A moving vibrator unit (13) brings the vibrator to rest in a defined setting, especially magnetically.