Hand-held pipette

Abstract

Hand-held pipettes are provided which have automatic volume setting and either manual or power assisted piston operation. Power assisted piston operation may be achieved with a fly-by-wire operation wherein movement of a plunger button is detected and used to control a drive for the plunger. A data transfer capability in at least one direction may also be provided for the pipette.

What is claimed is:  
     
         1 . A hand-held pipette including a manually-driven piston mechanism for aspirating and dispensing fluid, and an automatic volume setting mechanism which includes a stroke control stop for said piston mechanism and a mechanism for automatically setting said stop.  
     
     
         2 . A hand-held pipette including: 
 a tip receiving nozzle;    a manually controlled piston connected to apply negative aspirating and positive dispensing pressure to said nozzle;    a stroke control stop for said piston; and    an apparatus which automatically controls the position of said stop, and thus the volume of fluid aspirated.    
     
     
         3 . A pipette as in  claim 2  wherein said apparatus includes a stop drive mechanism, and a control for operating said drive mechanism.  
     
     
         4 . A pipette as in  claim 3  wherein said drive mechanism includes a motor driven worm gear.  
     
     
         5 . A pipette as in  claim 3  wherein said control includes a processor, input elements for providing information to said processor, and outputs for indicating at least current volume setting for said stop.  
     
     
         6 . A pipette as in  claim 5  wherein said processor is operative to calibrate said pipette.  
     
     
         7 . A pipette as in  claim 5  wherein said processor includes a memory storing presets for stop position.  
     
     
         8 . A pipette as in  claim 5  wherein said processor stores and utilizes volume compensation algorithms.  
     
     
         9 . A pipette as in  claim 2  including a manually operable button and a linkage between the button and piston for operating said piston.  
     
     
         10 . A pipette as in  claim 9  including a switch positioned to be operated when said button is fully depressed.  
     
     
         11 . A pipette as in  claim 10  wherein said apparatus for automatically controlling is operative only which said switch is operated.  
     
     
         12 . A pipette as in  claim 2  wherein said apparatus for automatically controlling includes a mechanism for facilitating rapid change for large stop position changes.  
     
     
         13 . A pipette as in  claim 2  including a control adapted to store stop settings, and data transfer apparatus which facilitates the transfer of said stop settings in at least one direction.  
     
     
         14 . A pipette as in  claim 2  including a power assist mechanism for said piston.  
     
     
         15 . A pipette as in  claim 14  including a manually operated piston actuator, said power assist mechanism being responsive to at least one of actuator position in its stroke and force on the actuator.  
     
     
         16 . A hand-held pipette including: 
 a tip receiving nozzle;    a piston connected to apply negative aspirating and positive dispensing pressure to said nozzle;    a plunger button having a selected stroke;    a drive for said piston;    a plunger button position detector; and    a mechanism operable in response to said detector for controlling said drive to move said piston at least at a rate and in a direction which are related to that of the plunger button.    
     
     
         17 . A pipette as in  claim 16  wherein said mechanism includes a processor which stores an indication of desired piston stroke, said processor receiving an indication of plunger button position in its stroke from said detector and operating said drive to move said plunger to a corresponding position in its stroke.  
     
     
         18 . A pipette as in  claim 17  including a mechanism which facilitates the transfer of pipette data of said processor in at least one direction.  
     
     
         19 . A pipette as in  claim 16  including an overblow stop detector for said plunger button, said mechanism stopping said drive in response to an output from said stop detector.  
     
     
         20 . A hand-held pipette including: 
 a tip receiving nozzle;    a piston connected to apply negative aspirating and positive dispensing pressure to said nozzle;    a plunger button;    a drive for said piston;    a detector for force applied to said plunger button; and    a mechanism operable in response to said detector for controlling said drive to move said piston at least at a rate and in a direction which are related to a force applied to the plunger button.    
     
     
         21 . A hand-held pipette including: 
 a tip receiving nozzle;    a piston connected to apply negative aspirating and positive dispensing pressure to said nozzle;    a manually operated piston actuator;    a drive for said piston; and    a mechanism operable in response to selected operation of said actuator for controlling said drive to move said piston at least at a rate and in a direction which are related to a selected parameter of the actuator.    
     
     
         22 . A pipette as in  claim 21  wherein said mechanism is responsive to at least one of actuator stroke and force applied to said actuator.