Pipetting device, pipette tip coupler, and pipette tip device and method

Abstract

A pipette assembly includes a pipette device, a pipette tip, and a leaf spring coupling device for coupling the tip to the pipette device, the coupling device including a plurality of circumferentially arranged elements or segments in the form of a flexible leaf spring, the flexible leaf spring having a stabilizer platform for retaining the pipette tip to the coupler and preventing the pipette tip from rocking on the coupler and a distal elastomeric element (such as an O-ring), and the pipette tip including dual complementary working surfaces in the pipette tip to provide precise control of an axial coupling position, the axial coupling position being defined as the axial distance from a distally facing axial stop surface of the pipette tip coupler to a liquid-contacting end of the pipette tip when the pipette tip coupler and the disposable pipette tip are in a coupled configuration.

Description

Technical Field

[0001] The present disclosure relates generally to pipetting devices and, more particularly, to pipette tip couplers, disposable pipette tips, pipette tip and coupler combinations, and methods of coupling and decoupling at least one disposable pipette tip to at least one pipette tip coupler operably carried by a pipette device. Background Art

[0002] Pipette devices are used in a variety of industries to transfer liquids for experimental analysis. Therefore, to provide control within the experiments being performed, disposable pipette tips are used and are intended for single-use. Disposable pipette tips are employed with both manual and automated pipette devices, which have a large number of pipette units arranged in rows or matrices for simultaneously aspirating samples from a large number of containers and dispensing them elsewhere.

[0003] Disposable pipette tips have been configured to be connected with conical or stepped coupling posts in history. When using a conical coupling post, the disposable pipette tip is constructed in such a way that it must be prestressed on the coupling post to provide airtight seal. Due to the tolerance of two docking components, the distance to the end in contact with the liquid of the pipette tip is not well controlled. In addition, high squeezing force is needed to prestress the pipette tip, to form airtight seal. As a result, microcracks may be formed in the pipette tip, which is the reason for leakage. In addition, the high squeezing force when placing the pipette tip has such shortcoming, namely, in order to discharge the pipette tip, corresponding high power must be applied.

[0004] Hamilton, the assignee of the present application, in U.S. Patent No. 7,033,543, issued on April 25, 2006, teaches a stepped coupling post in combination with an O-ring that provides a solution for reducing the high extrusion forces required to form an airtight seal and providing a well-defined axial positioning of the end of a pipette tip that contacts the liquid. When the O-ring is compressed, it provides an axially directed force to not only provide an airtight seal but also to engage an axial coupling feature on the coupling post with an anti-axial coupling feature on the pipette tip.

[0005] Nonetheless, current systems utilizing a stepped coupling post and separate O-ring configuration are problematic when the O-ring is damaged, as the result is a compromised hermetic seal and performance of the pipette device.

[0006] In addition, the compression of the O-ring causes the O-ring to deform, which in turn provides an axially directed force and an airtight seal against the working surface of the pipette tip. In contrast to this operation, when the compression of the O-ring is removed, the O-ring must be disengaged from the working surface of the pipette tip to allow the pipette tip to be removed from the coupling post and the pipette device for disposal. If the O-ring is not fully decompressed, some residual force will remain, causing the pipette tip to remain engaged to the coupling post, and therefore requiring an automated external axial reaction force to remove the pipette tip for disposal.

[0007] Furthermore, as the size of the wells to and / or from which liquids are transferred decreases, the need to precisely position all pipette tips in a controlled manner to allow for successful targeting increases.

[0008] Therefore, a need exists to improve upon or overcome one or more of the significant disadvantages outlined above. Summary of the Invention

[0009] Therefore, and in one aspect, embodiments of the present disclosure improve or overcome one or more disadvantages of the known prior art by providing a pipette tip coupler and disposable pipette tip combination, the combination comprising a plurality of circumferentially arranged elements or segments engaging a circumferential inner working surface defining a first working surface formed into an inner surrounding surface of a pipette tip side wall in an area above a proximally facing axial stop surface of the pipette tip for providing a synthetic prestress that axially prestresses the pipette tip, thereby causing a distal elastomeric element of the coupler to be prestressed against a second inner working surface of the pipette tip, thereby forming a sealing configuration that eliminates seal degradation or failure of the known prior art.

[0010] Additionally, and in one aspect, when the distal elastomeric element is pressed against the second internal working surface, it provides an anti-axial force to the multiple elements or segments, wherein at least one benefit of the anti-axial force is that when the multiple individual elements or segments are in radially and axially docked condition, the multiple individual elements or segments apply additional force to the first working surface to provide a stronger distal seal.

[0011] Another benefit of the counter-axial force is that when the multiple individual elements or segments are disengaged to the radially retracted state, the counter-axial force of the distal elastomeric element defines a counter-axially directed disengagement force that helps remove the pipette tip from the pipette tip connector for disposal.

[0012] On the other hand, an embodiment of the present disclosure provides a pipette tip coupler and a disposable pipette tip combination, wherein the coupler includes a plurality of circumferentially arranged elements or segments and a distal elastomeric element in the form of but not limited to an O-ring, and the pipette tip includes a double complementary internal working surface in the pipette tip to provide a synthetic axial force achieved by the engagement of the plurality of elements or segments and the distal elastomeric element with the double complementary working surfaces, for prestressing the disposable pipette tip into an axially coupled position provided by a distally facing axial stop surface of the pipette tip coupler and a proximally facing complementary reverse axial stop surface of the disposable pipette tip, so as to establish a vertical reference to the longitudinal axis of the channel of the pipette device carrying the pipette tip coupler and the disposable pipette tip combination, which provides straightness and controlled concentricity of the pipette tip.

[0013] Thus, one benefit of the resultant axial force coupling position over the known prior art is the establishment of this vertical reference, which provides for straightness and controlled concentricity of the pipette tip. As the angle between the transverse axis and the longitudinal axis perpendicular to the transverse axis (defined herein as ) increases, concentricity becomes worse. Therefore, controlled concentricity becomes particularly important for multi-channel systems and targeting multiple wells. Therefore, the combination of the pipette tip coupler and the disposable pipette tip provides tighter concentricity, thereby allowing tighter precision for all pipette tips in a controlled manner, thereby allowing successful targeting of multiple wells and / or smaller holes to and / or from which liquids are transferred.

[0014] On the other hand, embodiments of the present disclosure provide a pipette tip coupler and disposable pipette tip combination, the coupler comprising a plurality of circumferentially arranged elements or segments and a distal elastomeric element in the form of, but not limited to, O-rings and the pipette tip comprising dual complementary working surfaces in the pipette tip to provide precise control of the axial coupling position, the axial coupling position being defined as the axial distance from the distally facing axial stop surface of the pipette tip coupler to the end of the pipette tip that contacts the liquid when the pipette tip coupler and the disposable pipette tip are in the coupled configuration. This, combined with the straightness of the pipette tip, allows a pipette device carrying the pipette tip coupler and the disposable pipette tip combination to aim at smaller holes. Additionally, smaller volumes of liquid can be transferred because the known fixed distance of the disposable pipette tip allows the pipette tip / liquid to contact the working surface to which or from which the liquid is to be transferred in a controlled manner.

[0015] In another aspect, embodiments of the present disclosure provide a pipette tip coupler and disposable pipette tip combination that includes an angled compression mechanism that guides the movement of multiple individual components into contact with a first working surface of the pipette tip. The result is a greater axial force that prestresses the pipette tip into an axially coupled position.

[0016] On the other hand, an embodiment of the present disclosure provides a pipette tip coupler and a disposable pipette tip combination, the coupler comprising a plurality of circumferentially arranged elements or segments in the form of a flexible leaf spring with a retaining protrusion for retaining the pipette tip to the coupler, a stabilizer platform for preventing the pipette tip from rocking on the coupler, and a distal elastomeric element in the form of but not limited to an O-ring, and the pipette tip comprising dual complementary working surfaces in the pipette tip to provide precise control of an axial coupling position defined as the axial distance from a distally facing axial stop surface of the pipette tip coupler to a liquid-contacting end of the pipette tip when the pipette tip coupler and the disposable pipette tip are in a coupled configuration.

[0017] When combined with the accompanying drawings, according to the detailed illustrations provided below, other aspects of the embodiments of the present disclosure will become apparent. However, it should be understood that various modifications and adjustments can be made without departing from the scope and reasonable meaning of the present invention, and the preferred embodiments of the present disclosure are described in detail below. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The foregoing summary and the following detailed illustrations of the present disclosure will be more fully understood by reference to the following drawings, which are for illustrative purposes only and are not intended to limit the scope of the present disclosure. In addition, it will be understood that the drawings are not necessarily drawn to scale, as some components may be shown exaggerated or disproportionately relative to their actual dimensions in order to more clearly illustrate one or more concepts of the present disclosure. In the drawings:

[0019] Figure 1 A perspective view of an example embodiment of an air bleed pipette device assembly for an automated liquid handling system.

[0020] Figure 2 is a longitudinal cross-sectional side elevation view of an example embodiment of a pipette device assembly.

[0021] Figure 3 A partial longitudinal sectional side elevation view of an example embodiment of a pipette device assembly comprising a pipette device operably coupled to an example embodiment of an expansion spindle collet coupling or pipette tip coupling operably coupled to an example embodiment of a disposable pipette tip.

[0022] Figure 4 is a side elevation view of an example embodiment of a pipette device assembly.

[0023] Figure 5 is a partially exploded perspective view of a pipette device assembly detailing the components of an example embodiment of an expanding mandrel collet coupling.

[0024] Figure 6 is a partially exploded perspective view detailing components of an example embodiment of an expanding mandrel collet coupling device disposed between a disposable pipette tip and a pipette device.

[0025] Figure 7 is a side elevation view of an example embodiment of an expanding mandrel collet coupling.

[0026] Figure 8 Top and side perspective views of a center coupler body of an example embodiment of an expanding mandrel collet coupling.

[0027] Figure 9 Top and side perspective views of an example embodiment of a lower or distal elastomeric member or o-ring of an example embodiment of an expanding mandrel collet coupling.

[0028] Figure 10 1 and 2 are top and side perspective views of a distal elastomeric element surrounding a distal stem portion of a central coupling body, with a cylindrical spacer surrounding and mounted on the central body axially above the distal elastomeric element.

[0029] Figure 11 Top and side perspective views of an example embodiment of an expanding mandrel collet of an expanding mandrel collet coupling assembly.

[0030] Figure 12 A longitudinal cross-sectional side perspective view of an example embodiment of an expanding mandrel collet of an expanding mandrel collet coupling is provided.

[0031] Figure 13 Top and side perspective views of an example embodiment of an annular wedge of an example embodiment of an expanding mandrel collet coupling.

[0032] Figure 14 is a side elevational view of an example embodiment of an expanding mandrel collet in an expanded configuration by application of force from a piston sleeve or a compression sleeve, as shown in fragmentary form.

[0033] Figure 15 A partial longitudinal cross-sectional side elevation view of an example embodiment of an expansion mandrel collet operably coupled to an expansion mandrel collet coupling device of a pipette device.

[0034] Figure 16 is a partial, partially sectional side elevation view of an example embodiment of a disposable pipette tip operably coupled to a pipette device via an embodiment of an expanding mandrel collet coupling.

[0035] Figure 17 is a side elevation view of an example embodiment of a disposable pipette tip in a support position.

[0036] Figure 18 is a partial longitudinal sectional side elevation view of an exemplary embodiment of a disposable pipette tip showing details of its interior.

[0037] Figure 19 is a partial longitudinal sectional side elevation view of an upper coupling portion of an exemplary embodiment of a disposable pipette tip illustrating in detail the interior of the upper coupling thereof.

[0038] Figure 20 is a diagrammatic block diagram of an example embodiment of an automated pipetting workstation or system.

[0039] Figure 21 is a partial longitudinal cross-sectional side elevation view of an example embodiment of a pipette device supporting an example embodiment of an expanding mandrel collet coupling on a disposable pipette tip.

[0040] Figure 22 A partial longitudinal cross-sectional side elevation view of an exemplary embodiment of an expansion mandrel collet coupling device positioned on and into a disposable pipette tip defining a coupling stage wherein a distal elastomeric element initially contacts a sealing seat surface of the pipette tip and a plurality of discrete coupling elements or segments are in an uncompressed or radially outwardly unextended state, the sealing seat surface having an acute sealing seat surface angle relative to a central longitudinal axis of the pipette tip.

[0041] Figure 23 A partial longitudinal sectional side elevation view of an example embodiment of an expansion mandrel chuck coupling device and a pipette tip, wherein the pipette tip is lifted due to the downward push of a piston sleeve on an annular wedge so that the circular portions of multiple expansion mandrel chuck segments abut against the upper corners of a groove formed in the pipette tip and extend radially, thereby generating an axial force that lifts or pulls the pipette tip upward, which begins the process of seating the pipette tip and pressing the distal elastomeric element against the sealing seat surface of the pipette tip.

[0042] Figure 24 A partial longitudinal cross-sectional side elevation detail of a circular surface of one of the plurality of expansion mandrel clamp segment arms of an expansion mandrel clamp for a segmented coupler extending to coincide with the expansion mandrel clamp segment arms of the segmented coupler. Figure 23The corners of the pipette tip grooves are shown making contact.

[0043] Figure 25 is a partial longitudinal sectional side elevation view of the distal elastomeric element in abutment against Figure 23 The pipette tip's sealing seat surface is shown in its initially compressed state.

[0044] Figure 26 A partial longitudinal sectional side elevation view of an example embodiment of an expansion mandrel chuck coupling device further positioned in a pipette tip, wherein the pipette tip is lifted while the piston sleeve further depresses the annular wedge downward to continue radially extending the circular surfaces of the plurality of expansion mandrel chuck segments into the grooves of the pipette tip, thereby further pulling the pipette tip upward and further compressing the distal elastomeric element against the sealing seat surface of the pipette tip.

[0045] Figure 27 is a partial longitudinal sectional side elevation view of a circular surface of one of the plurality of expansion mandrel chuck segments, the expansion mandrel chuck segment further extending to Figure 26 into the groove of the pipette tip shown.

[0046] Figure 28 is a partial longitudinal cross-sectional side elevation detail of a distal elastomeric element, the distal elastomeric element being viewed from abutment against Figure 26 The initially compressed state of the sealing seat surface of the pipette tip is shown further compressed.

[0047] Figure 29 A partial longitudinal sectional side elevation view of an exemplary embodiment of an expanding spindle collet coupling device positioned on a disposable pipette tip, wherein the pipette tip is lifted to its final seated condition by moving the annular wedge to its final position, thereby defining a final coupled condition, wherein the distal elastomeric element is in a final compressed seated sealing condition against a sealing seat surface of the pipette tip.

[0048] Figure 30 is a partial longitudinal cross-sectional side elevational view of a circular surface of one of the plurality of expansion mandrel collet segments extending to abut a surface defining a groove, such as Figure 29 shown.

[0049] Figure 31 A detailed side elevation view of a partial longitudinal section of the distal elastomeric element, which abuts against Figure 29 The sealing seating surface of a pipette tip is shown in the final compressed, seated seal state.

[0050] Figure 32is a partial longitudinal cross-sectional side elevation view of the initiation of a coupling between an example embodiment of an expansion mandrel collet coupling device and a disposable pipette tip, with an illustration of the associated forces.

[0051] Figure 33 A partial longitudinal cross-sectional side elevation view of one of the plurality of arcuate or circular segment surfaces of one of the plurality of expansion mandrel collet segments coupling with a groove of an example embodiment of a disposable pipette tip with illustrative illustration of the associated forces.

[0052] Figure 34 A partial longitudinal cross-sectional side elevation detail view of a completed coupling between an example embodiment of an expansion mandrel collet coupling and a disposable pipette tip with an illustration of the associated forces.

[0053] Figure 35 is a partial longitudinal sectional side elevation view illustrating a misalignment coupling between an example embodiment of an expanding mandrel collet coupling device and a disposable pipette tip for defining a misalignment parameter.

[0054] Figure 36 is a partial and cutaway longitudinal cross-sectional side elevation view of one embodiment of a pipette device operably coupled to a misalignment coupling between an example embodiment of an expanding mandrel collet coupling and a disposable pipette tip for defining a misalignment parameter.

[0055] Figure 37 A partial and cutaway longitudinal sectional side elevation view of an example embodiment of an air evacuation pipette device coupled to an expanding spindle collet coupling device coupled to a disposable pipette tip having a small liquid volume clamped between the end of the pipette tip and a working surface, and having dimension lines illustrated and identified.

[0056] Figure 38 is a partial longitudinal sectional side elevation view illustrating in detail the interior of an example embodiment of a disposable pipette tip, with dimension lines illustrated and identified.

[0057] Figure 39 is a partial longitudinal sectional side elevational view of an example embodiment of a pipette device operably coupled to an example embodiment of an expanding mandrel collet coupling device, and illustrating and identifying the Figure 38 Dimension line of the center dimension line.

[0058] Figure 40A longitudinal side elevation view of a pipette device assembly illustrating a circuit board that processes signals from liquid level detection (LLD) circuit contacts, wherein the LLD circuit contacts are connected between the circuit board and a squeeze sleeve that contacts the plurality of segments or elements via an annular wedge, wherein the plurality of segments or elements are coupled to a pipette tip, wherein the distal end of the pipette tip is shown in contact with the liquid.

[0059] Figure 41 A partial longitudinal cross-sectional side elevation view of an example embodiment of an expanding mandrel collet coupling positioned on an example embodiment of a disposable pipette tip including an alternative sealing seat surface at a substantially 90 degree angle relative to a central longitudinal axis of the pipette tip.

[0060] Figure 42 A partial longitudinal sectional side elevation view of an exemplary embodiment of an expansion spindle collet coupling device positioned in a disposable pipette tip, including an alternative sealing seat surface angle of substantially 90 degrees, wherein the pipette tip is raised to its final seated state and the annular wedge is moved to its final position for defining a final coupled state, wherein the distal elastomeric element is in a final compressed and seated sealing state against the alternative sealing seat surface angle of substantially 90 degrees.

[0061] Figure 43 To support Figure 42 A partial longitudinal cross-sectional side elevation detail view of the distal elastomeric element in a final compressed state showing an alternative seal seat surface angle of substantially 90 degrees.

[0062] Figure 44 is a partial longitudinal sectional side elevation view of an example embodiment of a disposable pipette tip illustrating details of the interior of the disposable pipette tip including another alternative seal seat surface in the form of a circumferential radially concave seal seat surface.

[0063] Figure 45 is a partial longitudinal sectional side elevation detail of an example embodiment of a disposable pipette tip illustrating Figure 44 Detail of the circumferential radial concave seal seat surface shown in.

[0064] Figure 46 is a partial longitudinal sectional side elevation view of an example embodiment of a disposable pipette tip illustrating details of another alternative seal seat surface in the form of a circumferential radially convex seal seat surface.

[0065] Figure 47 is a partial longitudinal sectional side elevation view of an exemplary embodiment of a disposable pipette tip illustrating Figure 46 Detail of the circumferential radially convex seal seat surface shown.

[0066] Figure 48is a partial longitudinal sectional side elevation view of an example embodiment of a disposable pipette tip illustrating another alternative seal seat surface in the form of a circumferentially facing toothed edge seal seat surface.

[0067] Figure 49 is a partial longitudinal sectional side elevation view of an exemplary embodiment of a disposable pipette tip illustrating Figure 48 Detail of the tooth edge seal seat surface on the circumferential face shown.

[0068] Figure 50 A partial longitudinal sectional side elevation view of an example embodiment of an expansion mandrel collet coupling device positioned on an example embodiment of a disposable pipette tip, comprising an alternative V-shaped groove defined by a V-shaped circumferential inner surface of the disposable pipette tip, the groove being open toward the longitudinal axis and having a V-shaped cross-section as shown.

[0069] Figure 51 A partial longitudinal sectional side elevation view of an exemplary embodiment of an expansion mandrel collet coupling device positioned in a disposable pipette tip, comprising an alternative V-shaped groove wherein the pipette tip is raised to its final state, wherein the circular surfaces of the plurality of expansion mandrel collet segments extend into the V-shaped groove and extend to abut against the V-shaped circumferential inner surface, wherein the distal elastomeric element abuts against the sealing seat surface of the pipette tip in a final compressed sealing state.

[0070] Figure 52 is a partial longitudinal sectional side elevational view of a circular surface of one of the plurality of expansion mandrel collet segments extending into the V-shaped groove and abutting against a V-shaped circumferential inner surface defining the V-shaped groove, as shown in FIG. Figure 51 shown.

[0071] Figure 53 is a partial longitudinal cross-sectional side elevation view of an example embodiment of an expansion mandrel collet coupling positioned on a second example embodiment of a disposable pipette tip.

[0072] Figure 54 A partial longitudinal sectional side elevation view illustrating in detail the interior of a second exemplary embodiment of a disposable pipette tip.

[0073] Figure 55A partial longitudinal sectional side elevation view of an example embodiment of an expansion spindle chuck coupling device positioned in a second example embodiment of a disposable pipette tip, wherein a stop disk shoulder surface of the coupling device abuts an axial stop surface of the second example embodiment of the disposable pipette tip, and the circular surfaces of the plurality of expansion spindle chuck segments extend against an inner surface of an enclosing side wall of the second example embodiment of the disposable pipette tip, thereby causing deformation of the inner surface, and the distal elastomeric element is in a final compressed and seated sealing state against a sealing seat surface of the second example embodiment of the disposable pipette tip.

[0074] Figure 56 A partial longitudinal sectional side elevation view of a circular surface of one of the plurality of expansion mandrel collet segments of an expansion mandrel collet coupling device abutting against a Figure 55 The second exemplary embodiment of a disposable pipette tip is shown extending and deforming the inner surface of the surrounding side wall.

[0075] Figures 57 to 67 is a partial longitudinal sectional side elevational view of an exemplary embodiment of a disposable pipette tip comprising a Figure 19 An alternative groove shape embodiment of a circumferential annular nozzle groove is shown.

[0076] Figure 68 Top and side perspective views of a second or alternative example embodiment of an expanding mandrel collet of an expanding mandrel collet coupling assembly.

[0077] Figure 69 A longitudinal cross-sectional side perspective view of a second or alternative example embodiment of an expanding mandrel collet of an expanding mandrel collet coupling device.

[0078] Figure 70 A perspective view of an alternative example embodiment of an air bleed pipette device assembly for an automated liquid handling system.

[0079] Figure 71 A longitudinal cross-sectional side elevation view of one side of an alternative example embodiment of a pipette device assembly.

[0080] Figure 72 A partial longitudinal cross-sectional side elevation view of another side of an alternative example embodiment of a pipette device assembly.

[0081] Figure 73 A partially exploded view of the pipette assembly showing the details of Figure 72 Parts of the pipette assembly shown.

[0082] Figure 74 is a partially exploded parts perspective view of a pipette device assembly detailing parts of an example embodiment of a nozzle and leaf spring coupling arrangement.

[0083] Figure 75 is a partially exploded perspective view detailing parts of an example embodiment of a nozzle and leaf spring coupling arrangement sandwiched between a disposable pipette tip and a pipette device.

[0084] Figure 76 is a side elevation view of an example embodiment of a leaf spring coupling.

[0085] Figure 77 are top and side perspective views of an example embodiment of a leaf spring coupling.

[0086] Figure 78 Top and side perspective views of an example embodiment of a lower or distal elastomeric element or o-ring of an example embodiment of a leaf spring coupling device.

[0087] Figure 79 A partial longitudinal cross-sectional side elevation view of an example embodiment of a nozzle and leaf spring coupling operably coupled to a pipette device.

[0088] Figure 80 is a partial, partially sectional side elevation view of an example embodiment of a disposable pipette tip operably coupled to a pipette device via an embodiment of a nozzle and leaf spring coupling.

[0089] Figure 81 is a partial longitudinal sectional side elevation view of an example embodiment of a pipette device supporting an example embodiment of a nozzle and leaf spring coupling assembly on a disposable pipette tip.

[0090] Figure 82 A partial longitudinal sectional side elevation view of an example embodiment of a nozzle and leaf spring coupling device positioned on and into a disposable pipette tip, defining a coupling stage wherein the leaf spring is compressed, the retaining protrusion begins to enter the groove of the pipette tip, and the distal elastomeric element initially contacts a sealing seat surface of the pipette tip having an acute sealing seat surface angle relative to a central longitudinal axis of the pipette tip.

[0091] Figure 83 For Figure 82 A partial longitudinal cross-sectional side elevation detail view of the circular surface of one of the plurality of retaining protrusions of a leaf spring of a leaf spring coupling device shown contacting a corner of a pipette tip recess.

[0092] Figure 84 For Figure 82 A partial longitudinal cross-sectional side elevation view of the distal elastomeric element where the sealing seat surface of the pipette tip initially contacts is shown.

[0093] Figure 85 A partial longitudinal sectional side elevation view of an example embodiment of a nozzle, leaf spring coupling device and pipette tip, wherein the retaining protrusion of the leaf spring snaps into the groove of the pipette tip and the distal elastomeric element is compressed and seated against the sealing seat surface of the pipette tip.

[0094] Figure 86 A partial longitudinal cross-sectional side elevation view of one of a plurality of arcuate or circular segment surfaces of a retaining protrusion of a leaf spring coupling with a groove of an example embodiment of a disposable pipette tip with a graphical representation of the associated forces.

[0095] Figure 87 A partial longitudinal cross-sectional side elevation view of one of a plurality of arcuate or circular segment surfaces of a retaining protrusion of a leaf spring coupling with a groove of an example embodiment of a disposable pipette tip with a graphical representation of the associated forces.

[0096] Figure 88 Partial longitudinal sectional side elevation view of the completed coupling state between an exemplary embodiment of a leaf spring coupling device and a disposable pipette tip with an illustration of the associated forces.

[0097] Figure 89 is a partial longitudinal cross-sectional side elevation view of an example embodiment of a pipette device operably coupled to an example embodiment of a leaf spring coupling device, illustrating the Z-axis.

[0098] Figure 90 A partial longitudinal cross-sectional side elevation view of an exemplary embodiment of a leaf spring coupling device positioned in a disposable pipette tip including a substantially 90 degree alternative sealing seat surface angle, wherein the pipette tip is raised to its final seated state with the distal elastomeric element in a final compressed and seated sealing state against the 90 degree alternative sealing seat surface angle.

[0099] Figure 91 To support Figure 90 A partial longitudinal cross-sectional side elevation view of the distal elastomeric element in a final compressed state showing a 90 degree alternative seal seat surface angle. DETAILED DESCRIPTION

[0100] For the purpose of illustrating the disclosure, there are shown in the drawings embodiments that are presently preferred. These example embodiments will now be described more fully with reference to the accompanying drawings, wherein like reference numerals are used to refer to like parts or portions throughout the several views of the drawings.

[0101] Pipette assembly with expanding spindle collet coupling and tip

[0102] Figure 1 and Figure 2An example embodiment of a pipette device assembly 10 is illustrated, which includes an example embodiment of a pipette device 20, an example embodiment of an expansion spindle collet coupling device 100 or a pipette tip coupling device, and an example embodiment of a disposable pipette tip 220 removably coupled to the pipette device 20 via the expansion spindle collet coupling device 100.

[0103] Pipette device 20

[0104] See also Figure 2 The pipette device 20 includes a body 22 supporting an aspiration and dispense assembly 24 that includes a plunger 26 operatively coupled to and driven by a motor 28. The plunger 26 resides within a plunger barrel 30 extending from a distal or lower end 32 of the body 22 of the pipette device 20.

[0105] The pipette device 20 also includes an aspiration and dispense barrel 34 disposed at least partially within the plunger barrel 30 in axial alignment with and distally below the plunger 26. The aspiration and dispense barrel 34 transitions distally into a distal mounting flange 36 for attachment to an expansion mandrel collet coupling 100, which in turn removably couples with a disposable pipette tip 220.

[0106] See also Figure 1 、 Figure 3 and Figure 15 , the aspiration and dispense cylinder 34 further includes an inner surrounding sidewall 38 defining an open-ended pipette channel 40 extending therethrough. The open-ended pipette channel 40 extends longitudinally along the longitudinal channel axis 80 of the pipette device assembly 10 between the open upper end portion 42 and the open lower end portion 44 of the aspiration and dispense cylinder 34 for providing open communication between the plunger 26 and an outer region of the adjacent distal mounting flange 36, wherein the distal mounting flange 36 is operably coupled to the central body member 102 of the expansion mandrel collet coupling 100, and the central body member 102 includes an open-ended central channel 136 extending therethrough to provide open communication between the pipette tip 220 and the aspiration and dispense cylinder 34 via the expansion mandrel collet coupling 100.

[0107] Piston or squeeze sleeve 46

[0108] See also Figure 3 and Figure 4 , the pipette device 20 also includes a hollow piston or squeeze sleeve 46 having a proximal or upper end 48 and a distal or lower end 50. The squeeze sleeve 46 surrounds both the plunger cylinder 30 and the aspiration and dispense cylinder 34 and is operably coupled to a squeeze motor 52.

[0109] like Figure 4 As shown, the squeeze motor 52 of the pipette device assembly 10 is supported on the body 22 of the pipette device 20 and is operably coupled to and drives the lead screw 54, which in turn is coupled to an axially translating lead nut 56, which is operably coupled to a squeeze link 58. The squeeze link 58 is operably coupled to the proximal or upper end 48 of the squeeze sleeve 46 via a squeeze link arm 60, such that rotation of the squeeze motor 52 in a first direction causes the squeeze sleeve 46 to move along the longitudinal channel axis 80 ( Figure 3 ) in a distal or vertically downward direction and causes subsequent rotation of the extrusion motor 52 in a second or opposite direction to cause the extrusion sleeve 46 to move in a direction parallel to the longitudinal channel axis 80 ( Figure 3 ) in a linear counter-axial translation in the proximal or vertical upward direction opposite to the downward direction of the .

[0110] Ejector sleeve 62

[0111] See also Figure 4 The pipette device 20 further comprises an ejection sleeve 62 for ejecting the disposable pipette tip 220 from the pipette device 20, wherein the ejection sleeve 62 can be positioned relative to the aspiration and dispensing cylinder 34 ( Figure 2 ) moves axially and includes a proximal or upper end 64, a distal or lower end 66 and an ejector sleeve arm 68, which is attached to the ejector sleeve 62 at a first end adjacent the upper end 64 and has an opposite second end attached to the first end of the plunger device 70.

[0112] like Figure 5 As shown, the plunger assembly 70 includes an opposing end surface 72 abutting one end of an ejector sleeve spring 74, the ejector sleeve spring 74 having an opposing spring end abutting against an upper surface portion 76 of the main body 22 of the pipette assembly 20, wherein the ejector sleeve spring 74 is captured between the surfaces 72, 76 to be spring loaded to bias the plunger assembly 70 and the attached ejector sleeve 62 in a normal pipette tip ejection state.

[0113] The normal pipette tip ejection state is configured to require a force, such as one coupled to the pipette tip 220, to overcome the ejection sleeve spring force, thereby pushing the ejection sleeve 62 axially to the desired position. Figure 2 Shown in retracted position. Figure 2 Also shown is the ejector sleeve spring 74 surrounding a central spring guide member 78 for maintaining the shape of the ejector sleeve spring 74 and preventing the ejector sleeve spring 74 from buckling.

[0114] Furthermore, the ejector sleeve spring 74 is sized such that the force exerted by the ejector sleeve 62 on the pipette tip 220 during its relaxation is sufficient to assist in ejecting the tip 220 from the expanding spindle-collet coupling 100 .

[0115] It should be understood that the expanding mandrel collet coupling device 100 and the disposable pipette tip 220 may be implemented in other embodiments of pipette devices, with the embodiment of the pipette device 20 being provided by way of example only and not limitation.

[0116] Expansion mandrel chuck coupling device 100

[0117] See also Figures 5 to 7 , the expansion mandrel chuck coupling device 100 includes a slender center body member 102; a lower or distal elastomeric element 140, which is carried at the distal portion or lower end portion of the slender center body member 102; an expansion chuck 170, which is configured to surround the slender center body member 102 and includes a segmented shaft ring; and an annular wedge 210 or washer.

[0118] The annular wedge 210 is configured to receive an upper portion of the elongated center body member 102 therethrough for axially movable movement over the interior of the expansion collet 170 adjacent the segmented collar for radially outwardly expanding the segmented collar from an unexpanded state having a first circumference to an expanded state having a second circumference greater than the first circumference based on the axial position of the annular wedge 210 relative to the center body member 102 for expansion from, for example, Figure 21 The disengaged state shown is engaged as Figure 29 The interior of a pipette tip 220 is shown.

[0119] Slender central body member 102

[0120] More specifically, and see Figure 7 and Figure 8 The expansion mandrel collet coupling device 100 includes an elongated center body member 102 extending along the longitudinal center axis 90 between a proximal or upper annular end face 104 and a distal or lower annular end face 130 .

[0121] like Figure 8 As shown, the upper annular end surface 104 of the central body member 102 includes an outer chamfered perimeter 106 that transitions into an elongated tubular upper stem member 108 that transitions distally into an annular tapered portion 110. In one embodiment, the upper stem member 108 is threaded for assembly with the correspondingly threaded distal mounting flange 36. The diameter of the annular tapered portion 110 decreases from the upper stem member 108 and transitions distally into a cylindrical neck portion 112. The cylindrical neck portion 112 transitions distally into a cylindrical collar 114 having a larger diameter than the cylindrical neck portion 112.

[0122] Cylindrical collar 114 is followed by a lower cylindrical body member 120 having a diameter greater than the diameter of cylindrical neck portion 112. Body member 120 extends distally from cylindrical collar 114 to an upper annular shoulder end or stop surface 122 of a distal cylindrical shaft surface 124 having a diameter greater than the diameter of lower cylindrical body member 120.

[0123] like Figure 8 As shown, the distal cylindrical shank surface 124 transitions from the upper annular shoulder end 122 to a circular end plate 126 having an upper surface 128 and a lower surface defined by a distal or lower annular end surface 130. As shown, the end plate 126 has a diameter greater than the diameter of the distal cylindrical shank surface 124, wherein the distal cylindrical shank surface 124 defines a distal or lower recess 132 of the expanding mandrel collet coupling 100.

[0124] See also Figure 8 and Figure 15 The elongated central body member 102 includes an interior cylindrical channel surface 134 defining an open-ended cylindrical central channel or passageway 136 extending through the central body member 102 along the longitudinal central axis 90 between the upper annular end surface 104 and the lower annular end surface 130 for providing open channel communication through the elongated central body member 102 and to the open-ended pipette channel 40 extending longitudinally along the longitudinal channel axis 80 of the pipette device assembly 10.

[0125] Distal elastomeric element 140

[0126] like Figure 7 As shown, the expansion mandrel collet coupling 100 also includes a lower or distal elastomeric element 140 coaxially carried at a distal end portion of the elongated central body member 102 .

[0127] In one embodiment, and see Figure 9 , the distal elastomeric element 140 includes an annular body 142. The annular body 142 includes an inner surface 144 defining a central opening 146, a top surface 148, an outer peripheral surface 150, and a bottom surface 152. Figure 7 As shown, the central opening 146 is sized to closely or tightly surround the distal cylindrical shank of the expansion mandrel collet coupling 100 while being shaped to reside within the recess 132 and to extend radially outwardly circumferentially beyond the end plate 126. In a relaxed or uncompressed state, the distal elastomeric element 140 includes a circumferentially continuous, generally circular cross-sectional area 154, as shown. Figure 15 shown.

[0128] Spacer 160

[0129] See also Figure 10 The expansion mandrel collet coupling 100 further includes a spacer 160 configured to surround or be integrally formed with the elongated central body member 102. As shown, the spacer 160 includes a cylindrical body 162 extending between an upper end 164 and a lower end 165. The cylindrical body 162 includes an inner surrounding surface 166 ( Figure 15 ), which defines an open-ended passageway 168 extending through the cylindrical body 162, wherein the passageway 168 is sized to closely or tightly surround the lower cylindrical body member 120 of the elongated central body member 102.

[0130] See also Figure 7 、 10 15, the spacer 160 is further configured to be surrounded by the expansion mandrel collet 170, wherein the upper end 164 of the spacer 160 abuts against the distal end of the distal mounting flange 36, and the lower end 165 abuts against the inner annular shoulder stop surface 177 of the annular base portion 172 of the expansion mandrel collet 170, wherein the annular base portion 172 also includes a distal cylindrical rod portion ( Figure 8 ) on the distal annular shoulder stop surface 122 of the distal or lower annular base portion end 176 for fixing the expansion mandrel clamp 170 coaxially with the central body member 102 along the longitudinal center axis 90.

[0131] See also Figure 15 and 16 , and as described above, the upper handle member 108 of the expansion mandrel collet coupling device 100 is configured to be assembled within the distal mounting flange 36 of the aspiration and dispensing cylinder 34, for operably coupling the expansion mandrel collet coupling device 100 to the pipette device 20, and for removably coupling the disposable pipette tip 220 to the pipette device 20 through the expansion mandrel collet coupling device 100, so that the longitudinal channel axis 80 and the center axis 90 form a coincident or common longitudinal channel axis.

[0132] Expansion mandrel chuck 170

[0133] See also Figure 7 and 11 The expanding mandrel collet 170 includes a plurality of circumferentially spaced, upwardly extending collet arms 180 that transition upwardly from a lower end 184 attached to the lower annular base portion 172 to a free, segmented end defining a segmented collar disposed axially above the lower annular base portion 172. The plurality of circumferentially spaced, upwardly extending collet arms 180 are separated from one another by one of a plurality of circumferentially spaced, upwardly extending slots 182.

[0134] like Figure 11 and12 As shown, each of the plurality of upwardly extending collet arms 180 includes a respective lower arm portion 186 that transitions to a respective upper arm portion 190. In one embodiment, the plurality of circumferentially spaced lower arm portions 186 form a generally cylindrical surrounding lower body portion 181, and the plurality of circumferentially spaced upper arm portions 190 form a frusto-conical surrounding upper body portion 183 that transitions radially outward and upward from the lower body portion 181. The lower body portion 181 can be configured to have a slight upward taper or increased circumference relative to the distal or lower annular base portion 172.

[0135] annular base portion 172

[0136] See also Figure 11 and 12 The distal or lower annular base portion 172 includes a distal or downward facing base surface 171 and a proximally or upward facing base surface 173. The distally facing base surface 171 transitions downwardly into a shortened distal or lower annular stem surface 174 that terminates at a distal or lower annular base portion end 176 of the lower annular base portion 172. Figure 14 As shown, the base surface 171 and the annular base portion 172 define a shortened distal annular groove 178 .

[0137] See also Figure 12 and Figure 15 , the lower annular base portion 172 also includes an inner cylindrical surface 175 that transitions upwardly into an inner annular shoulder stop surface 177, as shown Figure 15 As shown, the spacer 160 is mounted on the inner annular shoulder stop surface 177. In addition, the inner cylindrical surface 175 is sized to have an inner diameter that closely surrounds the lower cylindrical body member 120 of the center body member 102 at a location directly above the annular shoulder stop surface 122 of the center body member 102, wherein the annular shoulder stop surface 122 defines an axial stop for the lower annular base portion end 176 of the expansion mandrel collet 170, so that the expansion mandrel collet 170 is centrally mounted on and around the elongated center body member 102.

[0138] Lower arm portion 186

[0139] like Figure 11 As shown, the lower arm portion 186 includes a distal or lower end portion 184 that is circumferentially spaced and attached to the lower annular base portion 172. Figure 12 As shown, the lower arm portion 186 also includes an upper end portion defining an intermediate arm portion having an inner annular concave segmented surface or groove 191 and an outer radially outwardly extending annular segmented stop disc 194 .

[0140] See also Figure 11 and Figure 12 The segmented stop plate 194 surrounds the exterior of the intermediate arm portions of the plurality of circumferentially spaced, upwardly extending collet arms 180 and extends radially therefrom, thereby defining an annular segmented stop plate.

[0141] like Figure 12 As shown, each segmented stop disk 194 includes a proximally or upwardly facing stop disk surface 198 and a distally or downwardly facing stop disk surface 196. Additionally, the plurality of lower arm portions 186 include inner cylindrical or inner segmented surfaces 188 sized to closely surround the spacer 160 with an inner diameter that surrounds the elongated central body member 102.

[0142] The distal or lower end of the inner segmented surface 188 transitions radially inwardly into the inner annular shoulder stop surface 177 which provides a stop surface for the spacer 160 as described above. The proximal or upper end of the inner segmented surface 188 transitions into the inner annular concave segmented surface or groove 191 .

[0143] Upper arm part 190

[0144] See also Figure 11 and Figure 12 , the plurality of circumferentially spaced upper arm portions 190 transition upwardly and radially outwardly from corresponding lower arm portions 186 and terminate in a plurality of free ends 199, which are disposed above and radially outwardly from the lower arm portions 186, wherein the plurality of free ends 199 include radially outwardly projecting segments defining a segmented shaft ring, wherein each segment includes an outer outwardly facing surface 202, and in one embodiment, the outer outwardly facing surface 202 is shaped as an outward circular or arcuate shape corresponding to the arcuate groove of an example embodiment of a pipette tip.

[0145] Thus, the upper arm portion 190 transitions upwardly and radially outwardly from the segmented stop disk 194 to a plurality of radially outwardly projecting segments that define a segmented collar, wherein the segmented collar is configured to surround the longitudinal center axis 90 of the expansion mandrel collet coupling 100, as shown. Figure 7 shown.

[0146] Additionally, the plurality of circumferentially spaced radially outwardly and upwardly extending upper arm portions 190, comprising segments, each include an inner surface 192 that forms a contact with the annular wedge 210 ( Figure 7 ) and an inclined segmented inner surface complementary to the proximal inclined annular side surface 216 of the upper arm portion 190, each of which includes a circumference that decreases distally relative to the Z axis, and wherein the inner surface 192 of the upper arm portion 190 is relatively inclined relative to the elongated central body member 102 ( Figure 15) forms a tapered gap 204 extending radially outward and upward.

[0147] In particular, and as Figure 15 As shown, the upwardly and radially outwardly inclined inner surfaces 192 of the plurality of circumferentially spaced upper arm portions 190 define a distally tapering conical gap 204 between the inner surfaces 192 of the upper arm portions 190 and a combination of the lower portion of the distal mounting flange 36 and the upper portion of the spacer 160. The tapered conical gap 204 is configured to receive a lower portion of an annular wedge 210 such that an annular wedge-shaped or inclined outer side surface 216 of the annular wedge 210 abuts the inner surfaces 192 of the plurality of free ends 199 that support the protruding segments that define the segmented collar.

[0148] Annular wedge 210

[0149] See also Figure 7 、 13 15, the annular wedge 210 includes a resilient wedge-shaped annular body having a circumferentially continuous generally wedge-shaped cross-section 211. The annular wedge 210 includes a central inner annular surface 212 defining a central annular opening 213 extending through the annular wedge 210, the central annular opening 213 being configured to movably surround the body.

[0150] Additionally, annular wedge 210 includes a planar circular top surface 214 configured to form an electrical contact switch with an LLD circuit contact ring end 366 of an LLD circuit and extending radially outward from a central inner annular surface 212 to a surrounding outer edge surface 215 .

[0151] In addition, annular wedge 210 includes a radially outwardly and proximally inclined side surface 216 that extends radially upwardly and outwardly from a bottom annular end 218 to the underside of an annular peripheral lip 219 that extends radially outwardly and terminates at a surrounding outer edge surface 215. Thus, the radially outwardly and proximally inclined side surface 216 defines a distally tapered wedge surface 216.

[0152] like Figure 15 As shown, the size of the central annular opening 213 of the annular wedge 210 is set to allow the distal mounting flange 36 and the slender tubular upper handle member 108 to pass through, so as to allow the radially outward and proximally inclined side surface 216 of the annular wedge 210 to be seated adjacent to the inner surface 192 of the plurality of radially outward protruding segments 200, so that the distal axial translation of the annular wedge 210 causes the radially outward protrusion of the radially outward protruding segments 200 of the expansion mandrel clamp 170 and the subsequent proximal translation of the annular wedge 210 causes the radially outward protrusion of the expansion mandrel clamp 170 to obtain radial retraction of the segments 200.

[0153] like Figure 15 As further shown, the upper handle member 108 of the expansion mandrel collet coupling device 100 is configured to fit within the distal mounting flange 36 of the aspiration and dispensing cylinder 34 for operably coupling the expansion mandrel collet coupling device 100 to the pipette device 20 of the pipette device assembly 10 such that the longitudinal channel axis 80 and the longitudinal center axis 90 form a coincident or common axis.

[0154] The expansion collet 170 is further configured to expand the segmented collar from an unexpanded state having a first circumference (e.g., Figure 7 ) expands radially outward to an expanded state having a second circumference greater than the first circumference (as shown Figure 14 shown).

[0155] Actuation of the extrusion motor

[0156] See also Figure 15 , the expansion mandrel collet coupling 100 is configured to fit within the distal mounting flange 36 with the flat circular top surface 214 of the annular wedge 210 disposed adjacent the distal end 50 of the compression sleeve 46. Thus, see Figure 4 and 15 , actuation of the squeeze motor 52 in a first direction causes linear axial translation of the squeeze sleeve 46 in a distal or vertically downward direction for applying a force axially on the top surface 214 of the annular wedge 210, thereby causing the distal tapered wedge surface 216 to slide further axially downward into the tapered gap 204, for forcing the distal tapered wedge surface 216 against the inner surfaces 192 of the plurality of radially outwardly projecting segments 200, for urging the outer radially outwardly facing surfaces 202 of the segments 200 radially outwardly against the spring tension of the upwardly extending collet arms 180 ( Figure 11 ) and contacts a first working surface of the pipette tip in the form of a surface 244 defining a recess 246 of a disposable pipette tip 220, as described below. Figure 29 Illustrated with examples.

[0157] Subsequent actuation of the extrusion motor 52 in a second direction opposite to the first direction returns the distal end 50 of the extrusion sleeve 46 to the Figure 15 The original position shown causes the annular wedge 210 to slide axially upward, thereby releasing the potential energy stored in the upwardly extending collet arm 180, thereby causing the outer radially outward facing surface 202 of the plurality of radially outwardly projecting segments 200 to retract from the groove 246 of the disposable pipette tip 220.

[0158] Pipette Tips 220

[0159] like Figure 2 and Figure 16 As shown, and as described above, the expanding mandrel collet coupling device 100 provides an open communication coupling between a disposable pipette tip 220 and the pipette device 20 of the pipette device assembly 10 .

[0160] See also Figures 16 to 18 , and in an example embodiment, the disposable pipette tip 220 includes an elongated tubular pipette tip body 222 having a central longitudinal axis 224. The pipette tip body 222 includes an elongated surrounding sidewall 226 that extends longitudinally along the central longitudinal axis 224 between a proximal annular end face 228 or upper annular end face and a distal or lower annular end face, defining an enclosed open proximal annular end 232 and an open distal annular end 234, respectively. The elongated surrounding sidewall 226 includes an inner surface 236 that defines a pipette tip channel opening 238 that extends longitudinally along the central longitudinal axis 224 of the pipette tip body 222 between the open proximal annular end 232 and the open distal annular end 234.

[0161] Thus, when the expanding spindle collet coupling device 100 is coupled between the pipette device 20 and the pipette tip 220, the pipette tip channel opening 238 is opened by the expanding spindle collet coupling device 100 ( Figure 16 )'s central passage 136 provides access from the open distal annular end 234 ( Figure 18 ) through the pipette tip 220 and to the pipette device channel 40 ( Figure 15 ) of the open communication. In this connection configuration, the central longitudinal axis 224 of the pipette tip body 222 is coextensive with the longitudinal channel axis 80 of the pipette device 20.

[0162] In an alternative embodiment, when the nozzle 3102 and the leaf spring coupling 3100 are coupled between the pipette device 3020 and the pipette tip 220, the pipette tip channel opening 238 is opened by the central channel 3136 of the nozzle 3102 and the leaf spring coupling 3100 ( Figure 80 ), providing a distal annular end 234 ( Figure 18 ) through the pipette tip 220 to the pipette device channel 3040 ( Figure 79 ) of the open communication. In this connection configuration, the central longitudinal axis 224 ( Figure 17 ) is coextensive with the longitudinal channel axis 3080 of the pipette device 3020.

[0163] first inner surface segment

[0164] See also Figure 18, and in an exemplary embodiment, the inner surface 236 of the elongated surrounding sidewall 226 includes a highest annular chamfered inner surface 240 that extends radially inward distally from the proximal annular end surface 228 of the pipette tip 220 and terminates by transitioning to a first substantially cylindrical inner surface segment 242 having a first diameter.

[0165] Axially arcuate circumferential surface defining the groove

[0166] like Figure 18 As shown, and in one exemplary embodiment, the first substantially cylindrical inner surface segment 242 includes an axially arcuate circumferential inner surface 244 formed into the elongated surrounding sidewall 226, which defines a circumferential annular groove 246. The annular groove 246 divides the first substantially cylindrical inner surface segment 242 into an upper first substantially cylindrical inner surface portion and a lower first substantially cylindrical inner surface portion of substantially equal diameter. Thus, the annular groove 246 provides an arcuate surface longitudinal cross-section for the circumferential, radially outwardly extending concave inner surface interruption of the first substantially cylindrical inner surface segment 242. The arcuate circumferential inner surface 244 can also be configured with alternative surface cross-sections as discussed below. And in one embodiment, the first substantially cylindrical inner surface segment 242 lacks the arcuate circumferential inner surface 244 defining the circumferential annular groove 246.

[0167] See also Figure 18 and Figure 19 The axially arcuate circumferential inner surface 244 defining the annular groove 246 includes an upper annular transition edge 248 that transitions distally into an upper axially arcuate circumferential surface sector 250 of the axially arcuate circumferential inner surface 244. The upper axially arcuate circumferential surface sector 250 then transitions distally into a lower axially arcuate circumferential surface sector 252 of the axially arcuate circumferential surface 244. The lower axially arcuate circumferential surface sector 252 then terminates at a lower annular transition edge 254.

[0168] The upper axial arcuate circumferential surface sector 250 or the upper partially annular groove 246 provides a central longitudinal axis 224 ( Figure 17 ) an increasing radius from the upper annular transition edge 248 to a maximum radius of the annular groove 246 relative to the central longitudinal axis 224, which defines the circumferential annular center of the annular groove 246. The lower axially arcuate circumferential surface sector 252 or lower portion provides the annular groove 246 with a decreasing radius from a maximum radius defining the circumferential annular center of the annular groove 246 to the lower annular transition edge 254 relative to the central longitudinal axis 224 of the pipette tip 220.

[0169] Second inner surface segment and annular shoulder stop surface

[0170] like Figure 18 As shown, the first basically cylindrical inner surface segment 242 is axially distally followed by a second basically cylindrical inner surface segment 262, and the second basically cylindrical inner surface segment 262 has a second diameter that is smaller than the first diameter of the first basically cylindrical inner surface segment 242, which is used to form a proximally facing, radially inwardly extending annular shoulder seat surface or axial stop surface 260, which is sandwiched between the first and second basically cylindrical inner surface segments 242, 262.

[0171] In one exemplary embodiment, the proximally facing axial stop surface 260 is substantially planar and generally perpendicular to the central longitudinal axis 224 of the pipette tip body 222. Figure 17 shown.

[0172] Third inner surface section and sealing seat

[0173] Also like Figure 18 and Figure 19 As shown, the second substantially cylindrical inner surface segment 262 is axially distally followed by a third substantially cylindrical inner surface segment 272 having a third diameter that is less than the second diameter of segment 262 .

[0174] Interposed between the second segment 262 and the third inner surface segment 272 is a frustoconical annular seal seat surface 270 or stop surface, which defines a distal working surface that is angled circumferentially radially inward and extends distally. The frustoconical annular seal seat surface 270 includes an upper annular seal seat edge 266 that defines an annular boundary between the second substantially cylindrical inner surface segment 262 and the frustoconical annular seal seat surface 270. Additionally, the frustoconical annular seal seat surface 270 includes a lower annular seal seat edge 268 that defines an annular boundary between the frustoconical annular seal seat surface 270 and the third inner surface segment 272, wherein the upper annular seal seat edge 266 has a larger diameter than the lower annular seal seat edge 268.

[0175] Thus, the frustoconical annular seal seat surface 270 defines a circumferential radially inwardly angled and distally extending second working or seal seat surface 270 that is sandwiched between the second substantially cylindrical inner surface segment 262 and the substantially cylindrical third inner surface segment 272 .

[0176] As shown, the seal seat surface 270 is disposed at an acute angle relative to the central longitudinal axis 224, wherein the acute angle defines an acute seal seat surface angle ( Figure 17In one embodiment, the preferred acute angle of the seal seat surface relative to the central longitudinal axis 224 is about 15 degrees to about 35 degrees, with a preferred angle of about 25 degrees. Figure 41 As shown, the alternative seal seat surface 2270 has an acute seal seat surface angle of approximately 90 degrees relative to the central longitudinal axis 224 .

[0177] Lower inner surface

[0178] Figure 18 Further illustrated is a fourth inner surface segment 274 following the substantially cylindrical third inner surface segment 272 , which is distally followed by a fifth inner surface segment 275 .

[0179] In one exemplary embodiment, the diameter of the fourth inner surface segment 274 tapers or decreases from the annular distal end 276 of the substantially cylindrical third inner surface segment 272 to the annular proximal end 278 of the fifth inner surface segment 275. Furthermore, the fifth inner surface segment 275 tapers or decreases in diameter distally from the annular proximal end 278 of the fifth inner surface segment 275 to the open distal annular end 234 of the pipette tip 220, which is intended for immersion. Additionally, and in one exemplary embodiment, the fifth inner surface segment 275 has a greater taper than the fourth inner surface segment 274.

[0180] External longitudinal ribs

[0181] See also Figure 17 , an exemplary embodiment of the pipette tip 220 includes a plurality of circumferentially spaced longitudinally extending external ribs 280 disposed on the tubular pipette tip body 222 adjacent to the periphery of the proximal annular end face 228 and extending longitudinally outwardly from the proximal annular end face 228 to an outer region surrounding the sidewall 226 adjacent to the substantially cylindrical third inner surface segment 272, as shown. Figure 18 shown.

[0182] In one example embodiment, the plurality of circumferentially spaced, longitudinally extending external ribs 280 may be used to provide support for the pipette tip 220 on or in a support surface 282 through which the pipette tip body 222 has passed, for example, via support surface apertures 284. One example embodiment of the support surface 282 may be in the form of, but not limited to, laboratoryware in the form of a tip rack as is known in the art and informed by the present disclosure.

[0183] Automated pipetting workstation or system

[0184] See also Figure 5 and Figure 20, and in one example of use and operation, one or more pipette device assemblies 10 are used in an automated pipetting workstation 300, which generally provides but is not limited to programmed transfer of liquids between containers, and includes one or more disposable pipette tips 220 mounted to an expansion spindle collet coupling device 100 operably carried by a pipette device 20 for performing, for example, programmed transfer of liquids between containers and ejection processes.

[0185] In one exemplary embodiment, the automated pipetting workstation 300 generally includes a robotic gantry 302 that carries at least one pipette device assembly 10 vertically above a horizontally disposed workstation table 304. The pipette device assembly 10 may include a single-channel pipetting head or a multi-channel pipetting head.

[0186] In addition, the robotic gantry 302 typically provides two or three degrees of freedom, wherein the three degrees of freedom include longitudinal translation along an axis defining the X-axis, lateral translation along an axis defining the Y-axis, and vertical (up and down) translation along an axis defining the Z-axis, such that the pipette device assembly 10 can move along the length (X-axis) and width (Y-axis) of the table, and vertically move up and down (Z-axis) relative to it. In the case of two degrees of freedom, the robotic gantry typically has the ability to translate the pipette device assembly 10 vertically and longitudinally or laterally.

[0187] In an example embodiment, the automated pipetting workstation 300 further includes a main controller 306 , a pipette axis controller 308 , and a power supply 310 that provides power to the main controller 306 , the pipette axis controller 308 , and the pipette device assembly 10 .

[0188] Additionally, and in one example embodiment, a computer / controller 320 may also be employed with the automated pipetting workstation 300 and communicate with the main controller 306 and the pipette axis controller 308 for controlling the robotic gantry 302 and the pipette device assembly 10, including associated process protocols for the pipette device assembly 10, such as the disposable pipette tip 220 attachment and ejection (coupling and detaching) process described in detail below.

[0189] In an exemplary embodiment, the computer / controller 320 generally includes a processor device or central processing unit (CPU) 322, a hardware read-only memory device (ROM) 324, a hardware main memory device (RAM) 326, a hardware storage memory 328 (the hardware storage memory 328 includes a non-transitory computer-readable medium or memory 330 having an operating system 332 and software 334, such as a user-defined program 336 for the pipette device assembly 10 stored thereby), a user display 338, a user input device 340, an input interface 342, an output interface 344, a communication interface device 346, and a system bus 348, which includes one or more conductors or communication paths that allow communication between devices of the computer / controller 320. The computer / controller 320 can also be operably connected to a LAN and / or a server 350. A power supply 352 provides power to the computer / controller 320.

[0190] Examples of the automated pipetting station 300 described above, including software, are currently manufactured and sold by Hamilton Corporation, 4970 Energy Road, Reno, Nevada 89502, USA, the assignee of the present patent application.

[0191] Pipette tip picking process with expanding mandrel collet coupling

[0192] Figures 21 to 31 Details of an example embodiment of successive stages of a pipette tip pickup process are illustrated, and in particular, a method of securely attaching a pipette tip 220 to an expanding mandrel collet coupling device 100 operably carried by a pipette device 20. As described above, and in an example embodiment, the pipette tip 220 can be supported by a support surface 282.

[0193] like Figure 21 As shown, the expansion mandrel collet coupling device 100 is connected to the pipette device 20 and, upon command, is positioned over the open proximal annular end 232 of the pipette tip 220 with their respective central longitudinal axes aligned along the Z-axis. The ejector sleeve 62 is in the ejected position, the compression sleeve 46 is in the uncompressed position, the expansion mandrel collet 170 is in a relaxed state, and the distal O-ring is in an uncompressed state.

[0194] Next, Figure 22The diagram illustrates moving the expansion spindle chuck coupling device 100 downwardly along the Z-axis into the pipette tip 220 to lower the distal elastomeric load-bearing portion of the expansion spindle chuck coupling device 100 to penetrate the inner cylindrical proximal portion of the pipette tip 220 so that the distal O-ring contacts the annular sealing seat surface 270 or stop surface of the tip 220 while maintaining the distal O-ring in an uncompressed state, and then engaging the upward-facing annular shoulder seat or axial stop surface 260 of the pipette tip 220 with the downward-facing axial stop disk surface 196 of the segmented stop disk 194.

[0195] Next, Figure 23 The expansion mandrel collet coupling 100 is shown further downwardly along the Z axis. Figures 23 to 25 , the compression sleeve 46 moves downwardly along the Z axis and pushes against the LLD circuit contact ring end 366, which contacts and pushes against the top surface 214 of the annular wedge 210, which is located above the expansion mandrel collet 170, while maintaining the plurality of radially outwardly projecting segments 200 in an unexpanded state, as shown. Figure 24 As shown in detail, the distal O-ring is maintained in an uncompressed state, as shown in FIG. Figure 25 As shown in detail, and before the axial stop surface 260 of the pipette tip 220 and the axial stop shoulder surface 196 of the segmented stop disk 194 are engaged, a gap 298 is maintained between the axial stop surface 260 of the pipette tip 220 and the axial stop shoulder surface 196 of the segmented stop disk 194 of the expansion mandrel collet 170, as shown in FIG. Figure 23 As shown in detail.

[0196] then, Figure 26 The illustration shows that the pressing sleeve 46 is further moved downward along the Z axis to push the annular wedge 210 against the inner surface 192 of the plurality of radially outwardly protruding segments 200, thereby pushing them radially outward and abutting the outer radially outwardly facing circular surfaces 202 of the plurality of radially outwardly protruding segments 200 against the upper axially arcuate circumferential surface sector 250 of the groove 246 of the disposable pipette tip 220, as shown. Figure 27 As shown in detail, the process for starting the process of squeezing or pushing the plurality of radially outwardly projecting segments 200 into the groove 246 and initially abutting the upper axially arcuate circumferential surface sector 250 of the axially arcuate circumferential inner surface 244 defining the groove 246 is as shown. Figure 26 As shown in Figure 27As shown in detail in FIG, the action of the plurality of radially outwardly projecting segments 200 extending or projecting into the recess 246 causes an axially upward force that begins the process of pulling the pipette tip 220 upward, thereby beginning the process of seating the annular shoulder seating surface of the pipette tip 220 with the axial stop shoulder surface 196 of the segmented stop disk 194 to close the gap 298 ( Figure 23 ) and compress the distal O-ring using the sealing seat surface 270 or the stop surface of the suction head 220, such as Figure 28 Shown in detail.

[0197] Figure 29 The squeeze sleeve 46 is shown moving downwardly along the Z-axis a configured predetermined length until it locks into position, thereby causing the annular wedge 210 to be stopped and locked into position by the squeeze sleeve 46 .

[0198] Thus, the plurality of radially outwardly projecting segments 200 radially extend to a desired distance or value, such as Figure 30 As illustrated, the axial stop shoulder surface 196 for seating the expansion mandrel collet coupling 100 fully against the annular shoulder seating surface of the pipette tip 220, with the two surfaces 196, 260 seated along an X-axis substantially perpendicular to the Z-axis to form a normal reference between the two axes.

[0199] At the same time, compress the distal O-ring to the desired distance or value, such as Figure 31 As illustrated, the annular sealing seat surface 270 for seating the distal O-ring with the tip 220 so that its cross-section is in its final compressed non-circular shape completes the attachment of the fixed pipette tip 220 to the expansion spindle collet coupling device 100 operably carried by the pipette device 20.

[0200] Upon completion of the secure attachment process detailed above, the plurality of radially outwardly projecting segments 200 and the distal elastomeric element 140 work in combination to create a segmented and sealed coupling that provides a fluid-tight seal, wherein the plurality of radially outwardly projecting segments 200 are at least partially received within the circumferential groove 246 and at least partially seated on the circumferential arcuate inner surface 244 defining the circumferential groove 246 ( Figure 18 ), and wherein the distal elastomeric element 140 seals against a sealing seat surface 270 of the pipette tip 220, wherein, in one embodiment, the sealing seat surface 270 provides a surface that is angled radially inward and extends distally or downwardly.

[0201] Thus, the plurality of radially outwardly projecting segments 200 move radially outwardly to engage the circumferential grooves 246 ( Figure 18), thereby coupling with the suction head 220, and moving radially inward to release the suction head 220 in accordance with the movement of the annular wedge 210. Applying a force for axially moving the annular wedge 210 downward causes the plurality of radially outwardly projecting segments 200 to be pushed to a radially outward position, and releasing the force on the annular wedge 210 causes energy to be released from the cantilever 180 ( Figure 11 ) is released, causing the segment to rebound from a radially outward position to a radially inward position.

[0202] Disposable pipette tip ejection process

[0203] Figures 21 to 31 The details of the successive stages of an example method or process for ejecting a pipette tip 220 from an expansion mandrel collet coupling device 100 operably carried by a pipette device 20 are illustrated in reverse. The tip ejection process sequence is similar to the attachment or tip pick-up securing process sequence, except in reverse, and Figure 34 The distal o-ring axial force component of the compressed distal o-ring is illustrated, which provides the force to assist in removing the tip 220 during the ejection process.

[0204] In one exemplary embodiment, the ejection process includes the following steps: (1) positioning the tip in a location where it is to be discarded, such as a waste container; (2) moving the squeeze sleeve 46 upward, wherein the force is released from the annular wedge 210, and as a result, the force is also released from the plurality of radially outwardly projecting segments 200 to allow retraction from the groove 246 in the tip 220, the distal O-ring begins to release stored elastic potential energy or spring energy as a force against the tip 220, and wherein the spring-loaded ejection sleeve 62 also pushes against the tip 220 to push it away, causing the tip to begin to be released from the plurality of radially outwardly projecting segments 200; (3) continuing to move the squeeze sleeve 46 upward, wherein the plurality of radially outwardly projecting segments 200 continue to be released from the groove 246 in the tip 220. and (4) further continuing to move the compression sleeve 46 to its uppermost position, wherein the plurality of radially outwardly projecting segments 200 return to their original, retracted free state and fully disengage the groove 246 in the tip 220, and wherein the distal O-ring returns to its original shape and the spring-loaded ejector sleeve 62 pushes against the tip 220 until the tip is pushed away from the expansion mandrel collet coupling by the spring-loaded ejector sleeve 62 and the spring-loaded ejector sleeve 62 becomes fully extended.

[0205] In view of the foregoing, those skilled in the art will appreciate that these tip installation and ejection processes are applicable to a wide variety of mechanically and / or automatically driven pipette types and designs.

[0206] Connection force and ejection force

[0207] Figure 32 A diagrammatic vector diagram of the plurality of radially outwardly projecting segments 200 of the expanding mandrel collet coupling 100 is illustrated, the segments 200 initially extending into the groove 246, wherein the radially rounded surfaces 202 of the plurality of radially outwardly projecting segments 200 contact the upper corner of the tip groove above the center of the segment radius, thereby generating an axially upward force that pulls the pipette tip 220 upward. Figure 32 As shown, the segment force (Fsegment_total force) of each of the plurality of radially outwardly protruding segments 200 is composed of two components: an axial force (Fsegment_axial) component and a radial force (Fsegment_radial) component.

[0208] As long as the plurality of radially outwardly protruding segments 200 are contacting the upper corner of the suction head groove above the center of the segment radius ( Figure 33 Dimension Z in the figure), Fsegment_axial will increase as the distance between the segment radius center and the groove corner increases. Therefore, at the beginning of the pickup process, the segment axial force (Fsegment_axial) is initially low, such as Figure 32 shown, and in Figure 33 and increases to its maximum value at the end of the tip picking process, as Figure 34 shown.

[0209] See also Figure 33 , the ratio of Z / R is equal to SIN(ω), and SIN(co) is equal to (Fsegment_Axial) / (Fsegment_Resultant). Therefore, (Fsegment_Axial) is equal to (Fsegment_Resultant) multiplied by the ratio of Z / R. Therefore, the result is that (Fsegment_Axial) increases as Z increases.

[0210] See also Figure 34 The segment axial force (Fsegment_axial) forces the segmented stop disc 194 against the seat of the nozzle 220 and provides the force required to overcome the O-ring axial force (Fdistal_ring_axial) and compress the distal O-ring. The O-ring has an O-ring force (Fdistal_ring_resultant) generated by compression, and this O-ring force includes two components: an axial component (Fdistal_ring_axial) and a radial component (Fdistal_ring_radial). In addition, the segment radial force (Fsegment_radial) provides the groove 246 ( Figure 18), and the distal O-ring radial force component (Fdistal_ring_radial) provides the radial force required to maintain the seal against the tip. Furthermore, the segment-to-tip groove geometry, which results in an increase in Fsegment_axial as the segment enters the groove (increasing dimension Z), helps overcome the O-ring axial force (Fdistal_ring_axial), allowing the distal O-ring to be fully compressed to the desired degree. Furthermore, the distal O-ring axial force component (Fdistal_ring_axial) provides a force to aid in removing the tip 220 during the ejection process.

[0211] Alignment / Misalignment

[0212] The axial shoulder surface 196 of the expanding mandrel collet coupling 100 and the axial shoulder seat of the nozzle 220 are important for proper nozzle alignment. Therefore, the expanding mandrel collet coupling 100 and nozzle 220 are configured such that the plurality of radially outwardly projecting segments 200 urge the axial shoulder surface 196 and the axial shoulder seat together to prevent misalignment, as positional error (E) can be significant if the shoulders do not mate correctly, especially if they are tilted.

[0213] For example, and as Figure 35 and 36 As shown, the misalignment angle The relationship between the tip axial distance (D) and position error (E) is: For example, for a misalignment angle of two degrees With a tip axial distance of 90 mm, the position error (E) is 3.14 mm, which is considered very high considering that typical position error tolerances are usually plus or minus 0.5 mm.

[0214] Figure 37 The axial shoulder surface 196 and the axial shoulder seat are shown in flush contact with each other to provide correct alignment and maintain a constant axial distance D of the tip from the tip seat to the distal end 230 to establish proper tip alignment when the pipette tip end is at a known and controlled distance along the vertical or axial axis Z and the perpendicular axis X. This is important for allowing the pipette device to target small holes and small volumes of liquid. In addition, smaller volumes of liquid can be transferred because the known fixed distance of the pipette tip allows controlled contact of the pipette tip / liquid with the working surface 290 (to or from which the liquid 292 is to be transferred).

[0215] Dimensions and Relationships

[0216] Therefore, for proper use and operation, the dimensions between the expansion mandrel collet coupling 100 and the suction head 220 are correspondingly correlated.

[0217] See also Figure 15 、 3839, the tip recess diameter A must be large enough to allow the segment 200 to pull the tip 220 upward and adequately lock the tip 220 in place. Conversely, if it is too large, the segment 200 may not be pushed in sufficiently to achieve a good lock. In addition, the inner diameters B and C must be larger than the outer diameter K of the segmented stop disk 194 and the outer diameter L of the annular base portion 172, respectively. However, they cannot be too large, as this may result in a poor fit and / or misalignment.

[0218] See also Figure 38 and 39 , the tip seat to groove dimension S must match the stop disc seat surface 196 to the center dimension M of the segment 200. This relationship is critical to the connection between the tip 220 and the segmented stop disc 194.

[0219] See also Figure 19 、 38 and 39, Figure 19 Dimensions from the tip holder surface to the O-ring sealing area ( Figure 38 Dimension F) must be aligned with the stop disc surface 196 to Figure 39 The tip surface and the retaining plate seating / coupling surface 196 must mate perfectly to provide proper alignment and maintain the tip axial distance D.

[0220] See also Figures 37 to 39 The dimension D (or axial distance) between the tip holder and distal end 230 and the coupling seat establish a known and controlled distance between the end of the pipette tip. This is important for allowing the pipette device to aim at small holes and small volumes of liquid. In addition, since the known fixed distance of the pipette tip allows controlled contact of the pipette tip / liquid with the working surface (to or from which the liquid is to be transferred), smaller volumes of liquid can be transferred.

[0221] See also Figure 15 、 38 39, the tip inner diameter G must be smaller than the diameter L of the annular base portion 172 to provide a seat or area for the distal O-ring to seal against. If the diameter G is too large, the distal O-ring may not seal properly. If the diameter is too small, the distal O-ring may not fully compress and may prevent the segmented stop disk 194 from seating, or may cause damage to the distal O-ring. Additionally, the ramp length H, together with the diameter G, controls the seat or area that mates with the O-ring. These dimensions are critical to providing a good O-ring seal. If the ramp length H is too long, the O-ring may not seal properly. If H is too short, the O-ring may not fully compress and may prevent the segmented stop disk 194 from seating, or may cause damage to the O-ring.

[0222] Liquid Level Detection (LLD) circuit contacts

[0223] See also Figure 40 , and in an example embodiment, the pipette device assembly 10 also includes a liquid level detection circuit assembly. The liquid level detection circuit assembly includes a liquid level detection or LLD circuit board 360, which includes processing circuitry 362 electrically coupled to LLD circuit contacts 364, the LLD circuit contacts 364 being operably coupled to a squeeze sleeve 46, the squeeze sleeve 46 being made of a non-conductive material so that it is insulated from the rest of the assembly, and wherein the contacts 364 terminate in circuit contact ring ends 366 recessed in a bottom region of the squeeze sleeve 46, the circuit contact ring ends 366 being configured for selectively Figure 22 The non-contact state shown and Figure 29 Between the illustrated contact states, the circuit contact ring end 366 is brought into contact with the annular wedge 210 and, therefore, the plurality of conductive segments or elements coupled to the interior first working surface of the conductive tip 220 .

[0224] like Figure 29 As shown, the LLD circuit contact 364 includes a circuit contact ring end 366 captured between the compression sleeve 46 and the annular wedge 210, wherein the LLD circuit board 360 ( Figure 40 ) forms an electrical closure or electrical contact between the processing circuit 362 of the RFID reader and the annular wedge 210 made of a conductive material. The annular wedge 210 pushes and electrically contacts the plurality of radially outwardly protruding segments 200, which are made of a conductive, non-brittle material.

[0225] Thus, with the nozzle attached and the plurality of radially outwardly protruding segments 200 pressed or pushed and locked into the nozzle groove 246 of the nozzle 220, the plurality of radially outwardly protruding segments 200 make electrical contact with the nozzle 220, which is also made of a conductive material. Figure 40 , which completes the circuit between the processing circuit 362 of the LLD circuit board 360 and the suction head 220.

[0226] Additionally, the retaining disc mounting post or distal mounting flange 36 is made of a non-conductive material. Thus, the body member 102 and the plurality of radially outwardly projecting segments 200 are insulated from the rest of the assembly.

[0227] Furthermore, when the tip 220 contacts liquid, the processing circuitry 362 of the LLD circuit board 360 detects a signal change, thereby enabling detection of the surface of liquid being transferred, or the surface onto or from which liquid is being transferred. Again, actuation occurs when the expanding mandrel collet coupling 100 is attached to the tip 220 and the plurality of radially outwardly projecting segments 200 are radially circumferentially pushed and locked into the tip recesses of the tip 220.

[0228] Alternative Example Embodiments

[0229] Figure 41 An example embodiment of an expansion mandrel collet coupling device 100 is illustrated positioned above an example embodiment of a disposable pipette tip 220, the device including an alternative sealing seat surface 2270 having an angle of substantially 90 degrees relative to a central longitudinal Z-axis of the pipette tip 220.

[0230] Figure 42 An example embodiment of an expanding spindle collet coupling device 100 positioned in a disposable pipette tip is illustrated, the device including an alternative sealing seat surface 2270, wherein the tip 220 is lifted to its final seated state and the annular wedge 210 is moved to its final position to define a final coupled state, wherein the distal elastomeric element 140 abuts the alternative sealing seat surface 2270 in a final compressed and seated sealing state.

[0231] Figure 43 The final compressed state of the distal elastomeric element 140 against the alternative seal seat surface 2270 is shown in detail.

[0232] Figure 44 The upper interior portion of the disposable pipette tip 220 is illustrated including another alternative seal seat surface in the form of a circumferential radially concave seal seat surface 3270 . Figure 45 Shown in detail Figure 44 Circumferential radial concave seal seat surface 3270 is shown.

[0233] Figure 46 An example embodiment of a disposable pipette tip 220 is illustrated, which illustrates details of another alternative seal seat surface in the form of a circumferential radially convex seal seat surface 4270. Figure 47 Shown in detail Figure 46 Circumferential radially raised seal seat surface 4270 is shown.

[0234] Figure 48 An example embodiment of a disposable pipette tip 220 is illustrated that illustrates yet another alternative seal seat surface in the form of a circumferentially upwardly facing toothed edge seal seat surface 5270 . Figure 49 Shown in detail Figure 48The circumferential upwardly facing tooth edge seal seat surface is shown in FIG.

[0235] Figure 50 is a partial longitudinal sectional side elevational view of an example embodiment of an expansion mandrel collet coupling device 100 positioned on an example embodiment of a disposable pipette tip 220, wherein the disposable pipette tip includes an alternative V-shaped groove 2246 defined by a V-shaped circumferential inner surface 2244 of the disposable pipette tip 220, the V-shaped groove 2246 being open toward the longitudinal Z axis and having a V-shaped cross-section as shown.

[0236] Figure 51 The expansion spindle collet coupling device 100 is shown positioned in a disposable pipette tip 220 that includes an alternative V-shaped groove 2246 ( Figure 50 ), wherein the suction head 220 is raised to its final state, the rounded surfaces 202 of the plurality of expansion mandrel collet segments 200 extend into the V-shaped grooves 2246 and abut against the V-shaped circumferential inner surface, and the distal elastomeric element 140 abuts against the sealing seat surface 270 of the suction head in a final compressed and seated sealing state.

[0237] Figure 52 The rounded surface 202 of one of the plurality of expanding mandrel collet segments 200 is illustrated extending into the V-shaped groove 2246 and abutting against the V-shaped circumferential inner surface 2244 defining the V-shaped groove 2246 .

[0238] Figure 53 An example embodiment of an expanding mandrel collet coupling is illustrated positioned on a second example embodiment of a disposable pipette tip 1220 that lacks the arcuate circumferential inner surface 244 defining the circumferential annular groove 246 .

[0239] Figure 54 The interior of a second exemplary embodiment of a disposable pipette tip 1220 is shown in detail, with all parts being similar except Figure 18 The interrupted inner surface segment 242 of the first substantially cylindrical inner surface segment 242 is shown without interruption, thereby defining an interrupted inner surface portion 1242 of the disposable pipette tip 1220 , wherein the inner surface portion 1242 defines a first working surface.

[0240] Figure 55An example embodiment of an expansion spindle clamp coupling device 100 is illustrated positioned in a second example embodiment of a disposable pipette tip 1220, wherein the stop disk shoulder surface 196 of the expansion spindle clamp coupling device 100 abuts against the axial stop surface 260 of the second example embodiment of the disposable pipette tip 1220, and the circular surfaces 202 of the multiple expansion spindle clamp segments 200 extend against the inner surface 1242 of the surrounding side wall of the second example embodiment of the disposable pipette tip 1220, thereby causing deformation 1244 of the inner surface 1242, and the distal elastomeric element 140 is in a final compressed and seated sealing state against the sealing seat surface 270 of the second example embodiment of the disposable pipette tip 1220.

[0241] Figure 56 Detailed view of a rounded surface 202 of one of the plurality of expansion mandrel collet segments 200 of the expansion mandrel collet coupling device 100 that abuts against Figure 55 The inner surface 1242 of the surrounding side wall of the second example embodiment of the disposable pipette tip is shown extending and deforming 1244 thereof.

[0242] Figures 57 to 67 is a partial longitudinal sectional side elevational view of an example embodiment of a disposable pipette tip comprising relative to at least Figure 19 The circumferential annular suction head groove of the segment 200 shown and at least Figure 50 An alternative groove shape embodiment of a segment 200 of a V-grooved portion is shown.

[0243] In particular, Figures 57 to 67 Alternative groove configurations 2251 to 2261 for receiving the segment 200 are illustrated respectively.

[0244] Alternative Example Embodiment Collet 2170

[0245] Figure 68 A second or alternative embodiment of an expansion mandrel collet 2170 is illustrated that is configured to expand the mandrel collet coupling 100 ( Figure 5 ) expansion mandrel chuck 170 ( Figure 5 ). The expanding mandrel collet 2170 is similar in function to the collet 170, but is configured for improved performance and life.

[0246] See also Figure 68 and Figure 69The expanding mandrel collet 2170 includes a plurality of circumferentially spaced, upwardly extending collet arms 2180 extending radially outward from a lower annular base portion 2172 and transitioning upwardly in an arcuate manner to terminate in a free segmented end 2200 defining a segmented collar disposed axially above the lower annular base portion 2172. The plurality of circumferentially spaced, upwardly extending collet arms 2180 are separated from one another by one of a plurality of circumferentially spaced, upwardly extending notches or slots 2182.

[0247] See also Figure 68 and 69 , each of the plurality of upwardly extending collet arms 2180 includes a respective lower arm portion 2186 that transitions to a respective upper arm portion 2190. In one embodiment, the plurality of circumferentially spaced lower arm portions 2186 form a surrounding lower body portion 2181, and the plurality of circumferentially spaced upper arm portions 2190 form a frusto-conical surrounding upper body portion 2183 that transitions radially outward and upward from the lower body portion 2181.

[0248] See also Figure 68 and 69 , the distal or lower annular base portion 2172 includes a distally or downwardly facing base surface 2171. The distally facing base surface 2171 transitions downwardly into a shortened distal or lower annular stem surface 2174, which terminates at a distal or lower annular base portion end 2176 of the lower annular base portion 2172. The base surface 2171 and the lower annular stem surface 2174 define a shortened distal annular groove.

[0249] like Figure 69 As shown, the lower annular base portion 2172 also includes an inner cylindrical surface 2175 that transitions upwardly to an inner annular shoulder stop surface 2177.

[0250] like Figure 69 As further shown, the lower arm portion 2186 includes circumferentially spaced lower end portions 2184 that are attached to the lower annular base portion 2172. The lower arm portion 2186 also includes an upper end portion defining an intermediate arm portion having an inner annular concave segmented surface or groove 2191 and an outer radially outwardly extending annular segmented stop disk 2194. The segmented stop disks 2194 surround and extend radially from the exterior of the intermediate arm portion of the plurality of circumferentially spaced upwardly extending chuck arms 2180 defining the annular segmented stop disks. Each segmented stop disk 2194 includes a proximally or upwardly facing stop disk surface 2198 and a distally or downwardly facing stop disk surface 2196. Additionally, the plurality of lower arm portions 2186 include an inner cylindrical or inner segmented surface 2188 that is sized to closely surround the spacer 160 ( Figure 10), the spacer 160 surrounds the elongated central body member 102 ( Figure 10 ).

[0251] See also Figure 68 and Figure 69 , the plurality of circumferentially spaced upper arm portions 2190 transition upwardly and radially outwardly from the corresponding lower arm portions 2186 and terminate at a plurality of free ends 2199, the free ends 2199 being disposed above and radially outwardly from the lower arm portions 2186, wherein the plurality of free ends 2199 include radially outwardly projecting segments that define a segmented collar, wherein each segment includes an outer outwardly facing surface 2202 that, in one embodiment, is shaped as an outwardly circular or arcuate surface. Thus, the upper arm portion 2190 transitions upwardly and radially outwardly from the segmented stop disk 2194 to the plurality of radially outwardly projecting segments that define the segmented collar. Additionally, the plurality of circumferentially spaced radially outwardly and upwardly extending upper arm portions 2190 comprising the segments each include an inner surface 2192 that forms a contact with the annular wedge 210 ( Figure 13 ) of the proximally inclined annular side surface 216 ( Figure 13 ) complementary inclined segmented inner surfaces.

[0252] Compare Figure 12 and Figure 69 The expanding mandrel collet 2170 widens the base of each lower end 2184 of each corresponding collet arm 2180 relative to the expanding mandrel collet 170 and radially extends the lower ends 2184 of the arms outward to increase the radius of each collet arm 2180 relative to the expanding mandrel collet 170. Pushing the lower ends outward and increasing their diameter allows for a larger chord or width at the lower end 2184 of each extension arm, wherein the increased width of each extension arm improves the strength of each extension arm. Additionally, the increased radial extension at the lower ends 2184 of the collet arms 2180 provides increased strength. The coupling function remains unchanged.

[0253] From an engineering perspective, the extension arm can also be modeled as a bent cantilever beam. Classic material strength techniques can be used to assess material stresses when the beam is subjected to bending, such as occurs when a coupler is engaged and disengaged. Additionally, when bending is repeated or cyclical, material stresses can be analyzed based on fatigue strength to provide adequate product life. Increasing the width at the beam base and the associated radius are geometric modifications used to reduce stress and improve strength.

[0254] Device

[0255] In one aspect, the pipette tip coupling or expansion mandrel collet coupling 100 may provide increased service life.

[0256] On the other hand, the radially outwardly protruding segments 200 of the expansion mandrel collet 170 provide a more rigid coupling for providing a more rigid connection between the pipette tip 220 and the expansion mandrel collet coupling device 100 .

[0257] On the other hand, the radially outwardly protruding segments 200 of the expanding mandrel collet 170 pull the suction head 220 upward and seat it efficiently.

[0258] On the other hand, the expanding mandrel collet coupling 100 will not be affected by ejecting the nozzle in free air. When the nozzle is ejected in free air, the life of the O-ring coupling is adversely affected because the O-ring is scratched and worn by the groove in the nozzle as the nozzle is pushed out by the spring-loaded ejection sleeve. The hardness of the radially outwardly projecting segments 200 resists the deleterious effects of this scratching and wear.

[0259] On the other hand, the material of the expansion mandrel collet 170 can be easily made of a conductive material to provide an electrical circuit to the nozzle for liquid level detection or other uses described in detail above.

[0260] On the other hand, the radially outwardly projecting segments 200 of the expansion mandrel collet 170 are made of a hard and durable material, such as, but not limited to, metal or hard plastic, to provide improved life, and because the discrete elements or segments are much harder than plastic tips, they work more efficiently into the tip grooves than soft elastomeric materials such as O-rings.

[0261] On the other hand, due to the efficient mechanical design, the radially outward-projecting segments 200 can be activated with low extrusion / axial forces. The lower extrusion / axial force requirement increases the life of the associated parts that provide the axial force. Due to this lower extrusion / axial force requirement, the radially outward-projecting segments 200 allow the lower or distal seal to have an increased life because the elastomeric material is not compressed as much.

[0262] On the other hand, the expanding mandrel collet coupling 100 allows for easy access to the lower or distal seal if replacement is necessary. Additionally, the lower or distal seal can be made from a wider variety of materials since it does not need to be electrically conductive for the LLD circuit.

[0263] On the other hand, maintenance costs are lower due to the increased lifespan and easier access to the lower or distal seal.

[0264] On the other hand, due to the improved seating, the alignment of the tip with the pipette device 20 is improved.

[0265] Methods

[0266] In view of the foregoing, and on the other hand, an exemplary embodiment of a method is provided for fixedly attaching at least one pipette tip to at least one pipette tip coupler, the at least one pipette tip coupler being in the form of an expansion mandrel collet coupling device carried by a pipette device, the method comprising: (1) providing a pipette tip including a side wall having an inner surrounding surface defining a channel opening extending between an open distal end intended for immersion in a medium to be pipetted and an open proximal end axially opposite the open distal end; (2) providing a pipette tip coupler including a side wall having an outer surrounding surface of the pipette tip coupler; and (4) providing a distally facing axial stop shoulder surface formed by an axially stepped connector shoulder of the surrounding surface, the distally facing axial stop shoulder surface being complementary to a proximally facing axial stop surface formed by an axially stepped shoulder surface of the inner surrounding surface of the pipette tip side wall; (3) providing a plurality of discrete coupling elements or segments that are circumferentially spaced and disposed on the upper seating surface of the pipette tip connector body; (4) providing a distal elastomeric element supported by the pipette tip connector at a position below the axially stepped connector shoulder; and (5) positioning the distal end of the pipette tip connector on the open proximal end of the pipette tip, wherein the pipette tip and (7) axially squeezing or pushing the plurality of discrete coupling elements or segments into a radially extended state adjacent to an upper axially arcuate circumferential surface sector of an axially arcuate circumferential inner surface defined on an axial stop surface of the pipette tip. A groove is formed into the inner surrounding surface of the side wall of the pipette tip at a square position for providing a proximally directed radial and axial composite prestress to the pipette tip for stimulating the distal elastomeric element to a compressed state, which is configured to provide an axial and radial sealing abutment between the outer circumferential portion of the distal elastomeric element and the inner working surface of the inner surrounding surface of the side wall of the pipette tip, which is angled radially inwardly and extends distally, and for abutting the proximally facing axial stop surface of the pipette tip with the distally facing axial stop surface of the pipette tip connector body to define the axial connection position of the pipette tip on the pipette tip connector device.

[0267] Based on the present disclosure described above, further structural modifications and adjustments may be made without departing from the scope and reasonable meaning of the embodiments of the present disclosure described above. For example, Figures 57 to 67 is a partial longitudinal sectional side elevation view showing in detail at least Figure 19 The groove 246 of the circumferential annular suction head shown in FIG. Figure 50 Different alternative example embodiments of the V-grooved segments 200 are shown in FIG. In particular, Figures 57 to 67 The diagram shows corresponding alternative groove configurations 2251 to 2261 for receiving the segment 200. In addition, the segments of the coupling may include radially outward faces that complement the corresponding different alternative example embodiments of the corresponding groove configurations 2251 to 2261. Thus, the first working surface is (but not limited to) Figures 53 to 56 , wherein the first substantially cylindrical inner surface segment 242 has no interruption, thereby defining an uninterrupted inner surface segment 1242 of the disposable pipette tip 1220. Furthermore, the distal O-ring seal seat of the tip may have different geometric shapes in the form of, but not limited to, a flat cone, a concave radius, a convex radius, a step, etc. Furthermore, the distal O-ring may have an alternative shape to the O-ring and may be in the form of, but not limited to, a configuration that is complementary to the distal O-ring seal seat of the tip.

[0268] Industrial Applicability

[0269] The above description of systems, assemblies, apparatus, and methods (including uses and operations) demonstrates the industrial applicability of the disclosed embodiments.

[0270] Therefore, it should be apparent that more structural modifications and adjustments may be made without departing from the scope and reasonable meaning of the embodiments of the present disclosure described above and below. Therefore, the spirit and scope of the present invention should not be limited to the above description of the embodiments of the present disclosure. Furthermore, unless expressly stated, reference to a singular element does not mean "one and only one", but rather "one or more". Furthermore, a device or method does not have to solve every problem that the present disclosure seeks to solve for it to be encompassed by the present invention.

[0271] Replacement Pipette Assembly 3010

[0272] Figures 70 to 75 An alternative example embodiment of a pipette device assembly 3010 is illustrated, including an example embodiment of a pipette device 3020, an example embodiment of a nozzle 3102, and an example embodiment of a leaf spring coupling device 3100 or a pipette tip coupler for use with a disposable pipette tip 220, wherein the disposable pipette tip 220 is removably coupled to the pipette device 3020 via the nozzle 3102 and the leaf spring coupling device 3100.

[0273] Pipette device 3020

[0274] See also Figure 71 and72 , the pipette device 3020 includes a body 3022 supporting an aspiration and dispense mechanism 3024 that includes a plunger 3026 operably coupled to and driven by a motor 3028. The plunger 3026 resides within a plunger barrel 3030 extending from a distal or lower end 3032 of the body 3022 of the pipette device 3020.

[0275] The pipette device 3020 also includes an aspiration and dispense cylinder 3034 that is at least partially disposed within the plunger cylinder 3030, in axial alignment with and distally below the plunger 3026. The plunger cylinder 3030 transitions distally into a distal mounting flange 3036 for attachment of the nozzle 3102. The leaf spring coupling 3100 is coupled to the nozzle 3102 at one end, and the leaf spring coupling 3100 is removably coupled to the disposable pipette tip 220 at the other end.

[0276] See also Figure 70 、 71 , 72, 77, and 79, the nozzle 3102 includes an aspiration and dispense cylinder 3034. The aspiration and dispense cylinder 3034 also includes an inner surrounding sidewall 3038 that defines an open-ended pipette channel 3040 extending therethrough. The open-ended pipette channel 3040 extends longitudinally along the longitudinal channel axis 3080 of the pipette device assembly 3010 between an open upper end portion 3042 and an open lower end portion 3044 of the aspiration and dispense cylinder 3034, providing open communication between the plunger 3026 and an exterior region adjacent to the distal mounting flange 3036. The distal mounting flange 3036 is operably connected to the nozzle 3102, which in turn is connected to the leaf spring coupling 3100. An open-ended central channel 3136 extends through the nozzle 3102 and the leaf spring coupling 3100 to provide open communication between the pipette tip 220 and the aspiration and dispense cylinder 3034.

[0277] Plunger bracket 3063 and ejector sleeve 3062

[0278] See also Figures 70 to 74 , the aspiration and dispense device 3024 includes a lead screw 3067 driven by a motor 3028. A lead nut 3054 is operably coupled to the lead screw 3067. In one embodiment, the lead nut 3054 is threaded and screwed onto the lead screw 3067. A plunger carriage 3063 surrounds and is operably coupled to the lead nut 3054 such that movement of the motor 3028 drives the lead nut 3054, which in turn drives the plunger carriage 3063 parallel to the longitudinal channel axis 3080.

[0279] The ejector block 3065 surrounds the lead screw 3067 and is located below the plunger carriage 3063. An ejector rod 3069 is operably connected to the end of the ejector block 3065. The ejector rod 3069 extends from the ejector block 3065 through the distal end or lower end 3032 of the main body 3022 of the pipette device 3020 via the passage 3021. An ejector spring 3074 surrounds the ejector rod 3069. The ejector spring 3074 is located between the distal end of the ejector block 3065 and the distal end or lower end 3032 of the main body 3022 of the pipette device 3020, so that the spring force acts in a direction that pushes the ejector block 3065 away from the plunger carriage 3063.

[0280] The pipette device also includes an ejection sleeve 3062 that surrounds the plunger cylinder 3030 and the nozzle 3102 and contains the aspiration and dispense cylinder 3034. The ejection sleeve 3062 is used to eject the disposable pipette tip 220 from the pipette device 3020, wherein the ejection sleeve 3062 is axially movable relative to the aspiration and dispense cylinder 3034 and the plunger cylinder 3030 and includes a proximal or upper end 3064, a distal or lower end 3066, and an ejection sleeve arm 3068 that is attached to the ejection sleeve 3062 at a first end adjacent to the upper end 3064 and has an opposing second end that is removably attached to a distal end 3071 of an ejection rod 3069.

[0281] When the pipette tip 220 is not installed, such as after the pipette tip 220 has been ejected, the ejector sleeve 3062 is in a free state. In order to install the pipette tip 220, the ejector sleeve spring force must be overcome to axially push the ejector sleeve 3062 to the retracted state, such as Figures 71 to 73 In addition, the ejection spring 3074 is sized to be long enough so that it provides a force to help eject the pipette tip 220 until the pipette tip 220 is completely separated from the leaf spring coupling 3100.

[0282] Nozzle 3102 and leaf spring coupling 3100

[0283] Figures 74 to 75 Illustrated are a nozzle 3102 and a leaf spring coupling 3100 for mounting a pipette tip 220 to a pipette device 3020 .

[0284] Nozzle 3102

[0285] More specifically, the nozzle 3102 includes a nozzle mounting portion 3103 located at the top end of the nozzle 3102, a nozzle stem 3107 located at the bottom end of the nozzle 3102 relative to the nozzle mounting portion, a nozzle body portion 3105 located between the nozzle mounting portion 3103 and the nozzle stem 3107, and a nozzle elastomeric member 3135. The nozzle mounting portion 3103 connects the nozzle 3102 to the distal mounting flange 3036 ( Figure 71 and 79 ).

[0286] like Figure 75 and 79 As further shown, the nozzle 3102 also includes a nozzle elastomeric member 3135 coaxially carried about the nozzle stem 3107 of the nozzle 3102. The nozzle stem 3107 is located at an opposite end of the nozzle mounting portion 3103 relative to the longitudinal center axis 3090 of the nozzle 3102. In the exemplary embodiment, the nozzle stem 3107 also includes a nozzle groove 3109, and the nozzle elastomeric member is carried within the nozzle groove 3109. In the exemplary embodiment, the nozzle elastomeric member 3135 is an O-ring.

[0287] Leaf spring connection device 3100

[0288] like Figures 74 to 77 As shown, the leaf spring coupling device 3100 includes a coupling cylinder 3173, a leaf spring cylinder 3175, a distal stem base 3121, and a distal or lower elastomeric element 3140 carried at the distal stem base 3121.

[0289] like Figure 76 and 77 As shown, the lower end 3171 of the coupling cylinder 3173 is connected to the leaf spring cylinder 3175. The leaf spring assembly 3170 is formed in the leaf spring cylinder 3175. The upper annular stop shoulder end 3177 of the leaf spring cylinder 3175 is located at the lower end of the leaf spring assembly 3170. The lower portion 3122 of the leaf spring cylinder 3175 is connected to the distal rod base 3121.

[0290] Also like Figure 76 and 77As shown, the distal stem base 3121 includes a cylindrical distal stem surface 3124 that transitions from an upper annular stop shoulder end to a circular end plate 3126 having an upper surface 3128 and a lower surface defined by a distal or lower annular end surface 3130. As shown, the diameter of the end plate 3126 is larger than the diameter of the narrowest portion of the cylindrical distal stem surface 3124, wherein the distal stem surface 3124 defines a recess 3132 at the distal end of the leaf spring coupling 3100. When the pipette tip 220 is coupled to the leaf spring coupling 3100, the upper annular stop shoulder end 3177 will abut the proximally facing axial stop surface 260 of the pipette tip 220 to prevent the leaf spring coupling 3100 from being inserted too far into the pipette tip 220.

[0291] Distal elastomeric element 3140

[0292] like Figure 76 and 77 As further shown, the leaf spring coupling 3100 also includes a distal elastomeric element 3140 coaxially carried at the distal stem. When the pipette tip 220 is coupled to the leaf spring coupling 3100, the distal elastomeric element 3140 acts as a seal.

[0293] In one embodiment, and see Figure 77 and Figure 78 , the distal elastomeric element 3140 includes an annular body 3142. The annular body 3142 includes an inner surface 3144 defining a central opening 3146, a top surface 3148, a peripheral outer surface 3150, and a bottom surface 3152. Figure 76 As shown, the central opening 3146 is sized to closely or tightly surround the distal stem portion of the leaf spring coupling 3100 while being shaped to reside within the recess 3132 and extend radially outwardly beyond the end plate 3126. In a relaxed or uncompressed state, the distal elastomeric element 3140 includes a circumferentially continuous, generally circular cross-sectional area 3154, as shown. Figure 79 shown.

[0294] Leaf spring assembly 3170

[0295] See also Figure 76 、 77 82, the leaf spring assembly 3170 includes a plurality of circumferentially spaced leaf springs 3180 formed in the leaf spring cylinder 3175 and arranged parallel to the longitudinal center axis 3090 and separated by open vertical slots 3182. The leaf springs 3180 are flexible. Each pair of adjacent leaf springs 3180 is separated by an open vertical slot 3182. The leaf springs 3180 are flexible and are used to retain the pipette tip on the leaf spring coupling device 3100.

[0296] Each leaf spring 3180 includes a retaining protrusion 3202 that protrudes from an outer surface 3185 of the leaf spring 3180. In one embodiment, each of the plurality of retaining protrusions 3202 has a rounded surface that protrudes from the outer surface 3185. When a pipette tip is coupled to the leaf spring coupling 3100, the plurality of retaining protrusions 3202 on the leaf spring assembly 3170 expand into the recess 246 of the pipette tip 220 to hold or retain the pipette tip 220 on the leaf spring coupling 3100.

[0297] Each leaf spring 3180 also includes a stabilizer platform 3183 protruding from an outer surface 3185 of the leaf spring 3180. When a pipette tip is coupled to the leaf spring coupling 3100, the multiple stabilizer platforms 3183 on the leaf spring assembly 3170 prevent the pipette tip from rocking. These stabilizer platforms 3183 prevent the tip from rotating on the leaf spring coupling 3100 around the retaining protrusion 3202 positioned within the groove 246 of the pipette tip 220. This rocking or rotation is one cause of misalignment between the end of the pipette tip 220 and the longitudinal center axis 3090. Furthermore, if a side load is applied, this type of rocking could cause the pipette tip seal to disengage. To prevent this problem, in one embodiment, the multiple stabilizer platforms 3183 are positioned above each leaf spring 3180, above or closer to the coupling cylinder 3173 relative to the retaining protrusion 3202. When the retaining protrusions 3202 have expanded into the grooves 246 of the pipette tip 220, the plurality of stabilizer platforms 3183 have an interference fit with the pipette tip 220. The plurality of stabilizer platforms 3183 add another point of contact between the pipette tip 220 and the leaf spring coupling 3100 to prevent the tip from rocking.

[0298] Pipette tip picking process using leaf spring coupling device 3100

[0299] Figures 81-85 Details of an example embodiment of successive stages of a pipette tip pickup process are shown, and in particular, a method of securely attaching a pipette tip 220 to a leaf spring coupling device 3100 operably carried by a pipette device 3020. As described above, in example embodiments, the pipette tip 220 may be supported by a support surface 282.

[0300] like Figure 73 、 77As shown in Figure 81, the leaf spring coupling device 3100 is connected to the pipette device 3020 via the nozzle 3102, and according to the instructions, the leaf spring coupling device 3100 is positioned on the open proximal annular end 232 of the pipette tip 220, wherein its respective central longitudinal axes are all aligned along the Z axis. The leaf spring 3180 is in a relaxed state. The ejection spring 3074 has pushed the ejection block 3065 and the ejection sleeve 3062 to the lowest position. The plunger bracket 3063 is positioned upward to allow the ejection block 3065 to move upward during the pipette tip picking process. The distal elastomeric element 3140 is in an uncompressed state.

[0301] Next, Figure 73 、 76 , 82, 83 and 84 illustrate the leaf spring coupling device 3100 along the Z axis ( Figure 81 ) moves downward into the pipette tip 220 for lowering the distal elastomeric load-bearing portion of the leaf spring coupling device 3100 into the inner cylindrical proximal portion of the pipette tip 220, thereby causing the distal elastomeric element 3140 to contact the annular sealing seat of the pipette tip 220 while maintaining the distal elastomeric element 3140 in an uncompressed state. The leaf spring 3180 has entered the pipette tip 220 and is in a compressed state. The pipette tip pushes the ejection sleeve 3062 and the ejection block 3065 upward. At this point, there is a gap 3298 between the axial stop surface 260 of the pipette tip 220 and the upper annular stop shoulder end 3177 of the leaf spring coupling device 3100, as shown Figure 82 In addition, see Figure 81 and 82 , showing the retaining protrusion 3202 beginning to move into the groove 246 of the pipette tip 220.

[0302] Next, Figure 77 and Figure 85 The leaf spring coupling 3100 is shown being moved further down the Z-axis into the pipette tip 220 until the leaf spring coupling 3100 is securely seated against the sealing seat of the pipette tip 220. The retaining projections 3202 on the leaf spring 3180 have reached and snapped into the grooves 246 on the pipette tip 220, locking the pipette tip in place on the leaf spring coupling 3100. The distal elastomeric element 3140 has pressed against the sealing seat in the pipette tip 220. The stabilizer platform engages the tip to prevent the pipette tip from rotating on the leaf spring coupling 3100.

[0303] After completing the fixed attachment process detailed above, the plurality of leaf springs 3180 and distal elastomeric element 3140 work in combination to create a segmented and sealed connection that provides a fluid-tight seal, wherein the plurality of retaining projections 3202 are at least partially received within the groove 246 of the pipette tip 220 and at least partially seated on the circumferential arcuate inner surface 244 ( Figure 18 ) and wherein the distal elastomeric element 3140 seals against a seal seat that provides a surface that is angled radially inward and extends distally or downwardly.

[0304] Disposable pipette tip ejection process using leaf spring coupling device 3100

[0305] Figures 81-85 Reversely illustrated are details of successive stages of an example method or process for ejecting a pipette tip 220 from a leaf spring coupling device 3100 operably carried by a pipette device 3020. This tip ejection process sequence is similar to the attachment or tip pick-up securing process sequence, except reversed.

[0306] like Figure 72 、 73 As shown in Figures 81-85, in one example embodiment, the ejection process includes rotating the lead screw 3067 so that the plunger carriage 3063 is driven downward into the ejection block 3065. The ejection block 3065 pushes the ejection sleeve 3062 downward via its attachment to the ejection rod 3069. The ejection sleeve 3062 begins to push the pipette tip 220 away from the leaf spring coupling 3100. The pipette tip 220 does not begin to move until the force is great enough to cause the leaf spring 3180 ( Figure 77 ) is compressed to allow the retaining protrusion 3202 to move out of the groove 246 in the pipette tip 220.

[0307] Next, the leaf spring 3180 has been fully compressed within the pipette tip 220. The pipette tip 220 is no longer vertically held to the leaf spring coupling 3100. At this point in the ejection process, the distal elastomeric element 3140 has lost contact with the seal seat, and the seal has therefore been broken. The plunger carriage 3063 continues to drive the ejection sleeve 3062 downward, pushing the pipette tip 220 away from the leaf spring coupling 3100.

[0308] Next, the pipette tip 220 continues to be driven out of the leaf spring coupling device 3100. The retaining protrusion 3202 reaches the opening of the pipette tip 220, and the leaf spring 3180 begins to expand toward the relaxed state.

[0309] When the ejection process is complete, the pipette tip 220 has lost contact with the leaf spring coupling 3100. The leaf spring 3180 is in a relaxed state. The ejection spring 3074 has pushed the ejection block 3065, and the ejection sleeve 3062 is in its lowest position. After the pipette tip 220 has been ejected, the plunger bracket 3063 is positioned upward to allow the ejection block 3065 space to move upward during the next pipette tip pickup process.

[0310] Connection force and ejection force of leaf spring connection device 3100

[0311] Figure 86 A diagrammatic vector diagram of the plurality of retaining projections 3202 of the leaf spring coupling 3100 is shown, initially extending into the groove 246, wherein the retaining projections 3202 on the leaf spring 3180 contact the upper corner of the groove 246 of the tip above the center of the retaining projection radius, thereby generating an axially upward force that pulls the pipette tip 220 upward. Figure 86 As shown, the retaining protrusion force or segment force (Fsegment_total force) of each of the plurality of retaining protrusions 3202 is composed of two components: an axial force (Fsegment_axial) component and a radial force (Fsegment_radial) component.

[0312] As long as the plurality of retaining protrusions 3202 are contacting the upper corner of the groove 246 of the nozzle above the center of the retaining protrusion radius ( Figure 87 Dimension Z in FIG), as the distance between the center of the retaining protrusion radius and the corner of the groove 246 increases, F segment_axial increases. Therefore, at the beginning of the pipette tip picking process, the segment axial force (F segment_axial) is initially low, such as Figure 86 shown, and in Figure 87 , and increases to its maximum value at the end of the pipette tip picking process, as shown in Figure 88 shown.

[0313] See also Figure 87 , the ratio of Z / R is equal to SIN(ω), and SIN(ω) is equal to (Fsegment_Axial) / (Fsegment_Resultant). Therefore, (Fsegment_Axial) is equal to (Fsegment_Resultant) multiplied by the ratio of Z / R. As a result, (Fsegment_Axial) increases as Z increases.

[0314] See also Figure 88, the segment axial force (Fsegment_axial) seats the upper annular stop shoulder end 3177 against the axial stop surface 260 of the pipette tip 220 and provides the force required to overcome the O-ring or distal elastomeric axial force (Fsegment_axial) and compress the distal elastomeric element 3140 or O-ring. The O-ring has an O-ring force (Fdistal_ring_resultant) generated by compression, and the O-ring force includes two components: an axial component (Fdistal_ring_axial) and a radial component (Fdistal_ring_radial). In addition, the segment radial force (Fsegment_radial) provides a force that locks the retaining protrusion 3202 to the groove 246 ( Figure 18 ), and the distal O-ring radial force component (Fdistal_ring_radial) provides the radial force required to maintain the seal against the pipette tip 220. In addition, as the retaining protrusion 3202 enters the groove 246 (increasing dimension Z), the retaining protrusion to the tip groove geometry causes Fsegment_Axial to increase, which helps to overcome the O-ring axial force (Fdistal_ring_axial), allowing the distal O-ring to be fully compressed to the desired degree. In addition, the distal O-ring axial force component (Fdistal_ring_axial) provides a force to assist in removing the tip 220 during the ejection process.

[0315] Alignment / Misalignment of Leaf Spring Coupling 3100

[0316] The upper annular stop shoulder end 3177 of the leaf spring coupling 3100 and the axial stop surface 260 of the pipette tip 220 are important for the correct alignment of the pipette tip. Therefore, the leaf spring coupling 3100 and the pipette tip 220 are configured so that the plurality of retaining protrusions 3202 push the upper annular stop shoulder end 3177 and the axial stop surface 260 together to prevent misalignment, because if the upper annular stop shoulder end 3177 and the axial stop surface 260 do not mate correctly, especially if they are tilted, the pipette tip 220 may align with the upper annular stop shoulder end 3177 and the axial stop surface 260. Figure 36 For the embodiment shown in FIG. 1 , the position error (E) may be significant.

[0317] Dimensions and Relationships of Leaf Spring Coupling 3100

[0318] Therefore, for proper use and operation, the dimensions between the leaf spring coupling 3100 and the nozzle 220 are relevant.

[0319] See also Figure 38 、 Figure 79 and Figure 85, the tip recess diameter A must be large enough to allow the retaining protrusion 3202 to pull the tip 220 upward and adequately lock the tip 220 in place. Conversely, if the tip recess diameter A is too large, the retaining protrusion 3202 may not be pushed in sufficiently to achieve a good lock. Additionally, the inner diameters B and C must be larger than the outer diameters K and L, respectively, of the upper annular stop shoulder end 3177. However, they cannot be too large, as this may result in an improper fit and / or misalignment.

[0320] See also Figure 38 and 85 , the tip seat to groove dimension S must match the upper annular stop shoulder end 3177 to the center dimension M of the segment 200. This relationship is critical to the connection between the tip 220 and the upper annular stop shoulder end 3177.

[0321] See also Figure 19 、 38 and 85, Figure 19 The dimensions of the axial stop surface 260 to the O-ring sealing area, Figure 38 Dimension F in the figure must correspond to the dimension from the upper annular stop shoulder end 3177 to the distally facing vertical lip surface 3179. Figure 85 These dimensions control the amount the distal O-ring is compressed and, therefore, the degree to which it seals. The axial stop surface 260 and the upper annular stop shoulder end 3177 must mate perfectly in order to provide proper alignment and maintain the tip axial distance D.

[0322] See also Figure 38 and 85 , the dimension D (or axial distance) between the axial stop surface 260 and the distal end 230 establishes a known and controlled distance of the pipette tip end. This is important for allowing the pipette device to aim at small holes and small amounts of liquid. In addition, since the known fixed distance of the pipette tip allows controlled contact of the pipette tip / liquid with the work surface (to or from which the liquid is to be transferred), smaller volumes of liquid can be transferred.

[0323] See also Figure 38 、 79As with 85, the tip inner diameter G must be smaller than the diameter L of the leaf spring coupling to provide a sealing seat or area for the distal O-ring. If diameter G is too large, the distal O-ring may not seal properly. If diameter G is too small, the distal O-ring may not fully compress, potentially preventing the upper annular stop shoulder end 3177 from seating, or potentially causing damage to the distal O-ring. Furthermore, the ramp length H, together with diameter G, controls the seat or area that mates with the O-ring. These dimensions are crucial to providing a good O-ring seal. If ramp length H is too long, the O-ring may not seal properly. If H is too short, the O-ring may not fully compress, potentially preventing the upper annular stop shoulder end 3177 from seating, or potentially causing damage to the O-ring.

[0324] Liquid level detection

[0325] The pipette device assembly 3010 also includes a liquid level detection circuit assembly, as described for the pipette device assembly 10 ( Figure 40 In an example embodiment, the nozzle 3102 and the leaf spring coupling 3100 material can be easily made of a conductive material to provide an electrical circuit to the pipette tip 220 for liquid level detection or other uses, as described in detail above with respect to the pipette device assembly 10.

[0326] Alternative Example Embodiments

[0327] Figure 90 An example embodiment of a leaf spring coupling device 3100 is illustrated positioned in a disposable pipette tip including an alternative sealing seat surface 2270, wherein the tip 220 is raised to its final seated state and the distal elastomeric element 3140 is in a final compressed and seated sealing state against the alternative sealing seat surface 2270.

[0328] Figure 91 The final compressed state of the distal resilient element 3140 against the alternative seal seat surface 2270 is shown in detail.

Claims

1. A pipette tip coupling device for coupling a pipette tip to a pipette device, the pipette tip coupling device comprising: A nozzle comprising: a nozzle mounting portion located at the top end of the nozzle; a nozzle stem located at the bottom end of the nozzle; a nozzle body portion located between the nozzle mounting portion and the nozzle stem; and a nozzle elastomeric member surrounding the nozzle stem; A leaf spring coupling connected to the bottom end of the nozzle, the leaf spring coupling comprising: a coupling cylinder for receiving the nozzle; A leaf spring cylinder comprising: A leaf spring assembly comprising: A plurality of leaf springs, each leaf spring comprising: External surface; a stabilizer platform protruding from said outer surface; a retaining protrusion having a rounded surface protruding from the outer surface; and an upper annular stop shoulder end at the lower end of the leaf spring cylinder; and lower part; a distal rod base connected to a lower portion of the leaf spring cylinder, the distal rod base comprising: distal cylindrical shaft surface; End Plate: a distal recessed portion; and wherein the distal cylindrical shank surface transitions from the upper annular stop shoulder end into a circular end plate forming the distal recessed portion; a distal elastomeric member disposed about the distal stem base; an open-ended central passageway forming an open pathway extending longitudinally from a top of the nozzle through a distal stem base of the leaf spring coupling; and wherein the nozzle stem is inserted into the leaf spring coupling device and abuts against an inner surface of the leaf spring coupling device to form a seal between the nozzle and the leaf spring coupling device.

2. The pipette tip coupling device according to claim 1, wherein The nozzle stem of the nozzle further comprises a nozzle groove, and wherein the nozzle elastomeric element is carried within the nozzle groove.

3. The pipette tip coupling device according to claim 1, wherein The nozzle elastomeric element comprises an O-ring and the distal elastomeric element comprises an O-ring.

4. The pipette tip coupling device according to claim 1, wherein The nozzle and the leaf spring coupling each further include an electrically conductive material.

5. The pipette tip coupling device according to claim 1, wherein: The plurality of leaf springs are configured to radially contract relative to a relaxed state when pressure is applied and to radially expand when pressure is released.

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