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

Inventors

Guzman, Jose Eduardo • Barresi, Thomas • Belton, Dana A.

Assignees

Hamilton Co Inc

Abstract

Pipette tip couplers, pipette tips, coupler and tip combinations, and methods for coupling and decoupling a pipette tip to or from, respectively, a pipette tip coupler mounted on a pipette device. The pipette tip couplers include an elastomeric element, a discrete segment assembly, and a coupler stop shoulder surface. The pipette tips include a groove in a first cylindrical section, a second cylindrical section, a tip stop shoulder surface at the interface of the first and second cylindrical sections, a third cylindrical section, a sealing seat surface at the interface of the second and third cylindrical sections, and a fourth section adjacent to the third cylindrical section. When the pipette tip is mounted on the pipette tip coupler, the discrete segment assembly abuts the tip groove, the coupler stop shoulder surface abuts the tip stop shoulder surface, and the elastomeric element abuts the sealing seat surface.

Core Innovation

The disclosed invention provides a pipette tip coupling device and a disposable pipette tip coupling system that secure a pipette tip by engaging a circumferential tip groove with a discrete segment assembly. The coupler body includes a distal stem portion and a distal end plate that surround an elastomeric element disposed around the distal stem portion adjacent to the distal end plate. The discrete segment assembly circumscribes the shank and forms a segmented ring with radially inward and radially outward surfaces, with a spring retainer radially circumscribing the radially outward surface of each discrete segment.

The coupling is configured to compress a distal elastomeric element, described as an O-ring, against a complementary sealing seat on the pipette tip to form a seal between the pipette tip coupling device and the pipette tip. The sealing seat is described using complementary frustoconical/seated geometry, including embodiments with alternative sealing-seat angles and radially concave or convex sealing-seat surfaces. The segmented ring, together with an annular wedge (squeeze ring), transfers force to seat and seal while maintaining alignment during coupling using mating axial stop shoulder surfaces.

In addition to sealing, the invention emphasizes mechanical alignment for improved concentricity/straightness for small-hole targeting and reduced seal deterioration. The use of circumferentially spaced rigid segments/balls actuated by an annular wedge supports rolling and wear-life benefits. The disclosure also includes embodiments with optional internal seal pipette tip assembly and alternative groove and sealing-seat geometries, and embodiments integrating liquid level detection by making selected segments and the tip electrically conductive.

Claims Coverage

Independent claim coverage centers on a segmented-ring coupler with spring-retained discrete segments, an elastomeric sealing element adjacent a distal end plate, and a coupler-to-shank diameter relationship. The claim set also includes an annular wedge that abuts the radially inward surfaces of the discrete segments, and an embodiment in which the discrete segments, pipette tip, and annular wedge are electrically conductive.

The claimed inventive features focus on a segmented-ring coupler with spring-retained discrete segments, an elastomeric sealing element adjacent a distal end plate, a coupler-to-shank diameter relationship, an annular wedge that abuts the discrete segments, and an electrically conductive embodiment for liquid level detection.

Stated Advantages

Documented Applications