Pipetting device, pipette tip coupler, and pipette tip: devices and methods

Inventors

Guzman, Jose Eduardo • Barresi, Thomas • Cummins, Trevor

Assignees

Hamilton Co Inc

Abstract

Pipette assembly that includes a pipette device, a pipette tip, and a leaf spring coupling device coupling the tip to the pipette device, the coupling device includes a plurality of circumferentially disposed elements or segments in the form of flexible leaf springs with stabilizer plateaus used to retain a pipette tip to the coupler and prevent the pipette tip from rocking on the coupler and a distal elastomeric element, such as an O-ring, and the pipette tip includes dual complemental working surfaces in the pipette tip to provide precise control of an axial coupled position defined as an axial distance from a distally facing axial stop surface of the pipette tip coupler to the end of the pipette tip that contacts liquid when the pipette tip coupler and disposable pipette tip are in a coupled configuration.

Core Innovation

A pipette tip coupling device and pipette tip assembly are disclosed in which a pipette tip includes an interior surface extending along a central longitudinal axis between an open proximal end and an open distal end. The pipette tip is secured and sealed using a nozzle and a leaf spring coupling device that connect through a nozzle stem portion inserted into the leaf spring coupling device to form a seal.

The leaf spring coupling device includes a coupling cylinder, a leaf spring cylinder, a distal stem base, and a distal elastomeric element disposed around the distal stem base. The leaf spring coupling device includes a plurality of leaf springs, each including an exterior surface, a stabilizer plateau, and a retention bump with a rounded surface, plus an upper annular stop shoulder end.

The retention bumps abut an inner surface of the circumscribing sidewall of the pipette tip for securing the pipette tip to the pipette tip coupling device. The distal elastomeric element abuts a second inner surface of the circumscribing sidewall of the pipette tip to form a seal between the pipette tip coupling device and the pipette tip, and the nozzle elastomeric element circumscribes the nozzle stem portion.

A second disclosed aspect defines the pipette tip interior with sections including an annular groove, a stop shoulder surface, and a sealing seat interposed between an upper annular sealing seat surface edge and a lower annular sealing seat surface edge, with a frustoconical section adjacent to the third section and between the third section and the open distal end. In this configuration, the retention bumps abut an annular groove of the pipette tip for securing, and the distal elastomeric element abuts the sealing seat for sealing. The disclosure further includes electrical liquid level detection using electrically conductive components and an annular wedge contact ring to close a circuit when the tip contacts liquid.

Claims Coverage

The provided independent claims cover 2 inventive features: a leaf-spring nozzle coupling with dual sealing interfaces, and a pipette tip interior geometry with annular groove, stop shoulder, sealing seat, and frustoconical section cooperatively engaging the leaf spring retention bump and the distal elastomeric element.

Across the independent claims, the core claim coverage is the cooperative leaf-spring retention and nozzle/distal elastomeric sealing arrangement with specific pipette interior structures that define the securing and sealing interfaces.

Stated Advantages

Documented Applications