Method and apparatus for simultaneous dilution and dispensation

A diluting dispenser for mixing a specimen with a diluent and substantially simultaneously dispensing the mixture, comprising

• syringe means including a diluent chamber, and means for drawing a predetermined volume of the diluent into said diluent chamber and for expelling the diluent from said diluent chamber, and
• pipette means including a dispensing tip, a specimen chamber and means for drawing a predetermined volume of the specimen into said specimen chamber,
• said diluent expelling means including nozzle means directed toward said dispensing tip and arranged for interaction with said specimen chamber in order to draw said specimen into intimately mixed relation with a jet of diluent as it passes toward said dispensing tip so that the mixture of diluent and specimen is dispensed substantially simultaneously as it is mixed, said means for drawing specimen into said specimen chamber comprising spring-loaded means forming an aspiration chamber in communication with said specimen chamber, wherein said spring-loaded means is shifted in a direction to contract said aspirating chamber by said means for expelling diluent from said diluent chamber.

A diluting dispenser for mising a specimen with a diluent and substantially simultaneously dispensing the mixture, comprising

• syringe means including a diluent chamber, and means for drawing a predetermined volume of the diluent from said diluent chamber, and
• pipette means including a dispensing tip, a specimen chamber and means for drawing a predetermined volume of the specimen into said specimen chamber,
• said diluent expelling means including nozzle means directed toward said dispensing tip and arranged for interaction with said specimen chamber in order to draw said specimen into intimately mixed relation with jet of diluent as it passes toward said dispensing tip so that the mixture of diluent and specimen is dispensed substantially simultaneously as it is mixed, said syringe means further comprising a reservoir from which diluent is drawn into said diluent chamber, wherein said diluent reservoir is formed by an element which is replaceably arranged within the diluting dispenser for communication with said means for drawing diluent into said diluent chamber.

A diluting dispenser for substantially simultaneously mixing a specimen with a diluent and dispensing the mixture, comprising a dispensing tip forming a restrictive opening for dispensing the mixture, means forming a specimen chamber in communication with said opening and means for directing a jet of the diluent into the specimen and toward said restrictive opening of the dispensing tip in order to draw the specimen into intermixed relation with the diluent jet for dispensation through said restrictive opening, the specimen being a liquid and said restrictive opening being sized to permit the specimen to be drawn into the specimen chamber and to permit passage of the jet of diluent and intermixed specimen, surface tension of the specimen normally preventing its passage through said restrictive opening, wherein an interior surface of said replaceable element tapers outwardly and longitudinally away from said restrictive opening to form said specimen chamber, said jet directing means comprising tubular means extending into the interior of said replaceable element in facing relation with said restrictive opening.

In a method for substantially simultaneously mixing a specimen with a diluent and dispensing the mixture, the steps comprising

• arranging a predetermined volume of the specimen in a specimen chamber in communication with a restrictive dispensing opening, and
• directing a jet of the diluent into the specimen and toward said restrictive opening in order to draw the specimen into intermixed relation with the diluent jet for simultaneous dispensation through said restrictive dispensing opening, further comprising the step of introducing fluid into the specimen chamber along with the diluent jet to assist in expelling the specimen and diluent from the specimen chamber.