Metering pump

Abstract

The invention relates to a pump ( 10 ) with a proportional-volumetrical dosing unit for conveying a predetermined volume of a liquid in a range of less than about 1 ml in a precisely dosed manner. The pump is provided with a cavity ( 22 ) for receiving the liquid and is limited on one side by a membrane ( 20 ) that can be displaced by means of a lifting device ( 18 ) to change the cavity's volume. The pump ( 10 ) further comprises a lockable inlet valve ( 30 ) between a liquid reservoir and the cavity ( 22 ), a lockable outlet valve ( 34 ) between the cavity ( 22 ) and a liquid dispenser and a lockable air vent valve ( 32 ) between the cavity ( 22 ) and the ambient atmosphere. The pump is especially useful for applying a precise, defined and reproducible volume of a lacquer or an adhesive on the surface of a disk-shaped data carrier for generating a thin lacquer or adhesive film.

1 . Pump with a proportional volumetric dosing unit for the precisely dosable delivery of a predetermined volume of a liquid in a range of less than approximately 1 ml, characterized in that the pump ( 10 ) comprises a cavity ( 22 ) for receiving the liquid and the cavity ( 22 ) is delimited on one side by a face ( 20 ), which for varying the cavity volume is movable by means of a lifting device ( 18 ), and that the pump ( 10 ) comprises an inlet check valve ( 30 ) between a liquid storage and the cavity ( 22 ), an outlet check valve ( 34 ) between the cavity ( 22 ) and a liquid dispenser and a venting check valve ( 32 ) between the cavity ( 22 ) and the ambient atmosphere.  
     
     
         2 . Pump as claimed in  claim 1 , characterized in that the cavity-side access to the venting valve ( 32 ) is connected with the highest position ( 40 ) of the cavity ( 22 ).  
     
     
         3 . Pump as claimed in  claim 1  or  2 , characterized in that it comprises a proportional magnet ( 12 ), whose coil core is formed at one end as a plunger ( 14 ) with the plunger ( 14 ) being in contact on an actuation piston ( 18 ) with which the face ( 20 ) is movable.  
     
     
         4 . Pump as claimed in  claim 3 , characterized in that the face delimiting the cavity ( 22 ) on one side, is a diaphragm ( 20 ) which is clamped in fluid-tight at the margin side.  
     
     
         5 . Pump as claimed in one of claims  3  or  4 , characterized in that the actuation piston ( 18 ) is automatically resettable via a reset spring ( 42 ).  
     
     
         6 . Pump as claimed in one of  claims 1  to  5 , characterized in that it comprises a store-programmable control (SPS).  
     
     
         7 . Use of a pump ( 10 ) as claimed in one of  claims 1  to  6  for the precise, defined and reproducible application of a predetermined volume of a lacquer or an adhesive agent onto a surface of a disk-shaped data carrier for generating a thin lacquer or adhesive agent film.