Laboratory pump unit

Abstract

A laboratory pump unit ( 1 ) for pipetting, filtering, and exhausting a gaseous or liquid fluid is provided. The laboratory pump unit ( 1 ) includes a pump ( 3 ), which can be connected on the suction side and/or the pressure side to a pipette ( 4 ) or other fluid receiver, for suctioning or ejecting the fluid. The laboratory pump unit includes, among other elements, a secondary tube ( 9, 10 ) that is connected to the suction tube and/or pressure tube ( 6, 7 ) that is connected to the pipette ( 4 ) or fluid receiver on the one hand and the pump ( 3 ) on the other hand, and is open to the atmosphere, and includes a throttle ( 11, 12 ) for limiting the amount of air drawn in or ejected. The laboratory pump unit ( 1 ) is operated in “open” pump operation on the suction side and pressure side with a precisely adjusted tube pressure in the suction tube or pressure tube ( 6, 7 ), which cannot be exceeded or fallen below by the pump (3).

1 . Laboratory pump unit ( 1 ) comprising a pump ( 3 ) which is connectable on a suction side and/or a pressure side with a pipette ( 4 ) or fluid receiver by a suction tube and a pressure tube, respectively, for drawing in or ejecting a fluid, a secondary tube ( 9 ,  10 ) is connected to at least one of the suction tube and the pressure tube ( 6 ,  7 ), and is connected to atmosphere, and a throttle ( 11 ,  12 ) is provided on the secondary tube for limiting a drawn in or ejected amount of air.  
     
     
         2 . The pump unit according to  claim 1 , wherein a control valve ( 13 ) is arranged in the suction tube ( 6 ) before, in the flow direction, a tube node connected to the secondary tube ( 9 ).  
     
     
         3 . The pump unit according to  claim 1 , wherein a control valve ( 14 ) is arranged in the pressure tube ( 7 ) after, in the flow direction, a tube node connected to the secondary tube ( 10 ).  
     
     
         4 . The pump unit according to  claim 1 , wherein at least one of an air filter and a noise damper is provided in a region of a tube end of the secondary tube ( 9 ,  10 ) open to the atmosphere.  
     
     
         5 . The pump unit according to  claim 1 , wherein the pump ( 3 ) can be selectively connected on the suction side to the pipette ( 4 ) or fluid receiver or to an suction tube ( 8 ), which is connected to at least one of a collecting container ( 16 ) and a filtering device.  
     
     
         6 . The pump unit according to  claim 5 , wherein a two-way or a three-way valve ( 5 ) is interposed in the suction tube ( 6 ) and selectively connects the pump ( 3 ) either to the pipette ( 4 ) or the like fluid receiver or to the suction tube ( 8 ).  
     
     
         7 . The pump unit according to  claim 1 , wherein a suction aperture for the suction tube ( 6 ) and an outlet aperture of the pressure tube ( 7 ) are arranged in an adapter ( 2 ) which is connectable to the pipette ( 4 ) or the fluid receiver, the adapter having a pistol grip form; and wherein the adapter ( 2 ) has at least one valve for selective connection of the pipette ( 4 ) or the fluid receiver to the suction tube or the pressure tube ( 6 ,  7 ).  
     
     
         8 . The pump unit according to  claim 1 , wherein the pump ( 3 ) comprises a diaphragm pump.