Programmable pipette

A programmable pipette comprising:

• a pipette assembly including piston means movable between a home position wherein it is ready to intake a volume of liquid and a discharge position wherein it is ready to dispense a volume of liquid previously aspirated into said assembly;
• a motor drive assembly connectable to said pipette assembly and including motor means for controlling movement of said piston means between the home and the discharge positions, and switch means for connecting said motor means to an electrical control unit;
• and a control unit means including microprocessor means for controlling said motor means to move said piston means between said home and discharge positions to perform pre-programmed modes of pipette operation, keyboard means for selecting one of said pre-programmed modes of pipette operation and for keying into said microprocessor means numeric data for liquid volumes to be aspirated and dispensed, and display means for displaying information stored in said microprocessor means requesting the input of data from said keyboard means and displaying said input data, said microprocessor means being programmed to display information requesting a data input concerning the rate at which a liquid is to be aspirated.

A programmable pipette according to clam 12 wherein said microprocessor means is programmed to display information requesting a data input concerning the rate at which a liquid is to be dispensed.

A pipette comprising:

• a pipette assembly including piston means movable between a home position wherein it is ready to intake a volume of liquid and a discharge position wherein it is ready to dispense a volume of liquid previously aspirated into said piston assembly;
• a motor drive assembly including a motor means for controlling movement of said piston means between its home and discharge positions;
• a control means including microprocessor means for controlling said motor means, wherein said motor means is a pulse actuated motor means that includes a longitudinally movable shaft means for engaging said piston means to drive it in a liquid dispensing direction, said shaft means being provided with magnet means and said motor drive means being provided with Hall Effect switch means so that when said magnet means activates said Hall Effect switch means said microprocessor means is signaled that said piston means is in its home position, and all subsequent movements of said piston means are controlled by the number of pulses fed to said motor means after said microprocessor means is signaled that said piston means is in its home position.

A pipette comprising:

• a pipette assembly including piston means movable between a home position wherein it is ready to intake a volume of liquid and a discharge position wherein it is ready to dispense a volume of liquid previously aspirated into said assembly;
• a motor drive assembly including motor means for controlling movement of said piston means between its home and discharge positions;
• and a control unit including microprocessor means for controlling said motor means, keyboard means for keying information into said microprocessor means, and display means for displaying information stored in said microprocessor means requiring the input of information from said keyboard means as to the nominal volume of liquid to be aspirated and dispensed and the actual volume of liquid dispensed, said microprocessor means including calibrating means for determining a calibration factor substantially equal to the ratio of the nominal volume of a liquid to be aspirated to the actual volume of the liquid dispensed so that thereafter the pipette will aspirate an actual volume of liquid equal to the nominal volume to be aspirated multiplied by the calibration factor.