Method and system for dosing and applying liquid reagent

Abstract

The invention relates to a method and a device for dosing and applying reagent fluid from a dosing head onto a surface in which the reagent fluid ( 30 a ) is continuously pumped in a circuit in the dosing head ( 2 ) that includes all fluid-carrying components, and, in the circuit, the reagent fluid is pumped from a supply container ( 30 b ) into a nozzle chamber ( 5 ) having at least one nozzle ( 6 ), with fluctuations in pressure being producible in the nozzle chamber ( 5 ) by means of a modulation element ( 7 ) such that the reagent fluid flows out of a nozzle ( 6 ) as a modulated continuous stream ( 9 ), breaks into individual drops ( 11 ) and is thus applied to the surface as individual drops ( 11 ) over a distance between the dosing head ( 2 ) and the surface.

1 . A dosing apparatus for dosing and applying reagent fluid from a dosing head onto a surface of a sample, the dosing head having a nozzle chamber that has at least one nozzle and fluctuations of pressure being creatable in the nozzle chamber by at least one modulation element such that the reagent fluid flows out of the nozzle as a modulated continuous stream that breaks into individual drops and thus may be applied to the surface as individual drops at a spacing from the dosing head and the surface wherein the dosing head includes all fluid-carrying components of the dosing apparatus, the reagent fluid being pumped in a continuous circuit in the dosing head, the reagent fluid being pumped in the circuit from a supply container into the nozzle chamber, and a base unit separate from the dosing head having only an electrical control unit that is connected to the dosing head exclusively by electrical lines. 
     
     
         2 . The dosing apparatus according to  claim 1 , further comprising a first electrode arrangement for giving the individual drops of reagent fluid an electrical charge and a capacitor for diverting the charged drops in an electrical field such that the drops contribute or do not contribute to a dosing, depending on their diversion. 
     
     
         3 . The dosing apparatus according to  claim 1 , further comprising a collection device by means of which drops of reagent fluid not contributing to a dosing may be collected and channeled back into the fluid circuit via at least one return line. 
     
     
         4 . The dosing apparatus according to  claim 1  wherein a total amount of reagent fluid of between 5 ml and 50 ml is in the fluid system. 
     
     
         5 . The dosing apparatus according to  claim 1  wherein the dosing head has a device for holding at least one supply container for reagent fluid. 
     
     
         6 . The dosing apparatus according to  claim 1  wherein the supply container may be exchanged using a quick-change mount. 
     
     
         7 . The dosing apparatus according to  claim 1  wherein the supply container has a penetrable rubber seal and the holding device has at least one needle for piercing the rubber seal. 
     
     
         8 . The dosing apparatus according to  claim 1  wherein the supply container is a commercial medication bottle. 
     
     
         9 . The dosing apparatus according to  claim 1  wherein the dosing head has a mount for holding a collection container. 
     
     
         10 . The dosing apparatus according to  claim 1  wherein the fluid system has at least one filter in the intake or return line of the fluid circuit. 
     
     
         11 . The dosing apparatus according to  claim 1  wherein at least one return line is optionally connected to the supply container or to the collection container. 
     
     
         12 . The dosing apparatus according to  claim 1  wherein the filters may be exchangeable. 
     
     
         13 . The dosing apparatus according to  claim 1  wherein the filters are combined into one common filter subassembly and the filter subassembly may be exchanged as a single unit. 
     
     
         14 . The dosing apparatus according to  claim 1  wherein it may be used to continuously produce drops of essentially the same size and the application volume may be determined by the number of drops applied. 
     
     
         15 . The dosing apparatus according to  claim 1  wherein it is divided into a supply subassembly and a production subassembly, in particular with these subassemblies connected to one another in a rotatable and/or tiltable fashion by a rotatable and/or tiltable connection element. 
     
     
         16 . The dosing apparatus according to  claim 15  wherein the devices for holding the at least one supply container and/or the collection container and/or the supply container and the collection container are combined into one mechanical supply subassembly. 
     
     
         17 . The dosing apparatus according to  claim 15  above wherein the devices for producing the drops are combined into one mechanical production subassembly. 
     
     
         18 . A dosing apparatus comprising:
 a dosing head;   a supply of reagent fluid in the dosing head;   a nozzle in the dosing head;   a supply line extending between the supply and the nozzle;   a return line separate from the supply and extending between the nozzle and the supply;   pump means for drawing reagent fluid out of the supply via the supply line and projecting the drawn-out fluid from the nozzle as a continuous stream so constituted as to form, at a distance from the nozzle, a succession of discrete drops applicable to a sample;   a base unit separate from the dosing head;   an electrical controller in the base unit; and   electrical lines connecting the controller in the base unit to the pump means in the dosing head, there being no other connection between the base unit and dosing head.   
     
     
         19 . The dosing apparatus defined in  claim 18 , further comprising
 electrode means in the dosing head juxtaposed with the nozzle for imparting an electrical charge to at least some of the drops and for deflecting a portion of the drops;   a collector in the dosing head positioned to intercept and catch the deflected drops; and   further pump means for recirculating the intercepted and caught drops from the collector to the supply.   
     
     
         20 . The dosing apparatus defined in  claim 19 , further comprising
 a filter between the further pump means and the supply for removing impurities from and adjusting the composition of the recirculated drops.