阅读说明：本技术 自动移液管模块中的吸头移除 (Pipette tip removal in automatic pipette modules ) 是由 V.辛提卡 于 2020-02-07 设计创作，主要内容包括：根据本发明的示例性方面,提供了一种自动移液器系统,包括：静止的接触表面、弹出器组件,该弹出器组件包括用于移液管吸头的支座,以及马达,该马达配置为使弹出器组件沿第一方向移动,使得吸头接触所述接触表面并从支座脱离。(According to an exemplary aspect of the present invention, there is provided an automated pipette system comprising: a stationary contact surface, an ejector assembly comprising a seat for a pipette tip, and a motor configured to move the ejector assembly in a first direction such that the tip contacts the contact surface and disengages from the seat.)

1. An automatic pipetting system comprising:

a stationary contact surface;

an ejector assembly comprising a seat for a pipette tip,

a motor configured to move the ejector assembly in a first direction such that the tip contacts the contact surface and disengages from the seat.

2. The system of claim 1, wherein the motor is coupled to the ejector assembly by a selective linkage.

3. The system of any preceding claim, wherein the motor is configured to dispense liquid by actuating a piston in a cylinder.

4. The system of any one of the preceding claims, wherein the tip holder protrudes through the contact surface.

5. The system of any one of the preceding claims, wherein the selective linkage device comprises a slide assembly comprising a locking hook and the ejector assembly comprises a locking tab, and the pipette tip is disengaged by first actuating the slide assembly in a second direction such that the locking hook engages the locking tab of the ejector assembly, and then actuating the slide assembly in a first direction such that the ejector assembly is actuated in the first direction relative to the body.

6. The system of any of the preceding claims, wherein the system further comprises a guide comprising a sloped surface in a third direction, the guide configured such that the ejector assembly contacts the sloped surface and the locking hook disengages from the locking tab.

7. The system of any one of claims 1 to 3, wherein the selective linkage comprises a lead screw connected to the motor and to a link connected to the ejector assembly.

8. The system of any one of the preceding claims, wherein the ejector assembly comprises a non-conductive material.

9. The system of any one of the preceding claims, wherein an upper surface of the tip contacts a surface of the module body.

10. The system of any one of the preceding claims, wherein the pipette comprises a selective reinforcement system comprising a reinforcement element and a spring.

11. A method for removing a tip attached to a tip mount of a pipette module, the method comprising using a motor configured to actuate an ejector assembly of the pipette module in a first direction relative to a module body such that the tip contacts a surface of the module body and disengages.

12. The method of claim 11, wherein the motor is selectively connected to the ejector assembly.

13. A method according to claim 11 or 12, wherein the motor is used to dispense a liquid.

14. The method of claim 12 or 13, wherein the selective linkage comprises a lead screw connected to a slide assembly and the ejector assembly comprises a locking tab, and actuation of the ejector assembly is achieved by first actuating the lead screw in a second direction such that the slide assembly engages the locking tab of the ejector assembly, and then actuating the lead screw in a first direction such that the ejector assembly is actuated in the first direction relative to the module body.

15. The method of any of claims 11-14, wherein the ejector assembly comprises a non-conductive material.

16. The method of any of claims 11-15, wherein the ejector assembly is disengaged from the motor by contacting an inclined surface.

Technical Field

The present invention relates to automatic pipettes and more particularly to automatic pipette devices, which may be air displacement pipettes.

Background

Pipettes are hand-held or automated media delivery devices for transferring precisely defined amounts of liquid from one container to another. The liquid is sucked into and discharged from a disposable tip attached to the lower end of the pipette.

In cylinder-based air displacement pipettes, air is expelled from the cylinder by dispensing liquid by downward movement of a plunger within the cylinder. The plunger has a range of motion within the cylinder. To aspirate the desired volume of liquid into the tip, the tip of the tip is placed in the sample liquid and the plunger is then retracted to the upper stop to receive the desired volume of liquid. Then, to dispense the desired volume of liquid, the tip of the pipette is moved to a receptacle for receiving the liquid, and the plunger is moved from the upper stop to the lower stop. The amount of liquid sucked and dispensed corresponds to the amount of air discharged.

Manual, that is, manual liquid dispensing pipettes typically have a mechanism for removing the tip so that the user does not need to remove the tip by manually grasping the tip. The tip is fixed to the lower end of a pipette tip mandrel or tip cone by friction. To detach the tip, the user presses a tip removal button, operable by the user's thumb, which is typically located in the upper portion of the pipette, near the control knob for aspiration and dispensing. The mechanism includes a removal sleeve that slides over the cylindrical portion of the pipette and an arm that is fixed to the cylindrical portion of the pipette and slides in or on the side of the handle of the pipette. The mechanism is connected to a spring which pushes the arm into an upper position. When the arm is pressed down, the sleeve disengages the tip (i.e., the end of the barrel) that is attached to the tip cone. To reiterate, when the user actuates the tip removal button, the removal sleeve is actuated downwardly and forces the tip out of the tip mandrel.

In electronic automatic pipettes, the removal of the tip is typically accomplished by using a separate tip removal motor. These solutions also typically utilize a return spring. There are also solutions in which the automatic pipette itself does not comprise a tip removal mechanism. In this type of solution, the suction head can be removed by: for example, by actuating a tip cone (connected tip) into a tip handling cartridge having a removal feature (e.g., a hook or notch) such that the tip is removed from the tip cone when the pipette is actuated or moved upward.

The above prior art solutions have inherent problems. For example, a separate tip removal feature requires excessive pipette movement. In addition, the process cartridge must be of a specific type to facilitate removal of the suction head. In solutions where the pipette head is removed by a separate motor, the pipette mechanism must be more elaborate and heavy, which results in higher requirements for actuating the pipette. A solution for removing the suction head by moving the whole assembly.

Us patent publication 2003/0147781 discloses a pipette comprising a body; an arm movable relative to the body parallel to the longitudinal direction of the pipette, so as to eject the cone fixed on the body; and a button for controlling the movement of the arm. The pipettes are arranged in the following manner: the button exerts a sliding thrust on the arm when the arm moves relative to the body.

In the alternative, as described in european publication EP3112026, the hand-held pipette may comprise a tip removal mechanism adapted to lift the internal mechanism of the pipette relative to the body of the pipette when a user presses a tip removal button. The disclosure also relates to a method for detaching a disposable tip attached to the tip cone of the pipette of the invention, and to a method of pipetting with a pipette according to the invention. However, in contrast to the present disclosure, this document discloses a system in which a first mechanism is used to transfer a first motive force to the cylinder to dispense the liquid, and a second mechanism is used for a second motive force.

Disclosure of Invention

The invention is defined by the features of the independent claims. Some embodiments are defined in the dependent claims.

According to a first aspect of the present invention there is provided an automated pipette system comprising: a stationary contact surface, an ejector assembly comprising a seat for a pipette tip, and a motor configured to move the ejector assembly in a first direction such that the tip contacts the contact surface and disengages from the seat.

According to a second aspect of the invention, there is provided a method for removing a tip attached to a tip holder of a pipette module, the method comprising using a motor configured to actuate an ejector assembly of the pipette module in a first direction relative to a module body such that the tip contacts a surface of the module body and disengages.

Drawings

FIG. 1 shows a schematic of an automated pipette module, in accordance with at least some embodiments of the present invention, an

Fig. 2 shows a schematic of an automated pipette module utilizing a detachment feature and detachment groove in accordance with at least some embodiments of the present invention, an

FIG. 3 shows a schematic of an automatic pipette module utilizing a detachment guide, in accordance with at least some embodiments of the present invention, an

FIG. 4 shows a schematic of a pipette tip removal sequence in accordance with at least some embodiments of the present invention;

FIG. 5 shows a schematic diagram of decoupling an ejector assembly from a slide assembly, in accordance with at least some embodiments of the present invention, an

Fig. 6 shows a schematic of an automated pipette module utilizing a detachment feature and detachment groove in accordance with at least some embodiments of the present invention, an

FIG. 7 illustrates a flow chart of a method that can support at least some embodiments of the present invention.

Detailed Description

In this context, the term "pipette" refers to a media delivery and handling device used in chemical, biological and medical applications, such as micropipettes. Such pipettes may utilize air displacement, positive displacement or, for example, volumetric techniques. Furthermore, the term "assembly" refers to a mechanism comprising at least one mechanical member and a support component, such as gears, screws, hooks, magnets, electrical and electromechanical components. Finally, the term "disposable tip" refers to a disposable tool typically made of plastic (e.g., polypropylene), or in some cases other materials such as plastic, which may be filled with carbon fibers or other additives. The volumes of the tips vary, for example, from 10 microliters to 10 milliliters, although larger or smaller volumes are used in the context of the present invention.

Typically, the reusable tip is removed from the pipette by having a "socket" that quickly lowers and pushes the tip off the tip holder. With the above method it is possible to remove the tips at a great number of speeds, resulting in too high a speed of travel of the separated tips. The disclosed invention allows for gentle nudging of the tip of the pipette, thus removing the tip at a minimum speed. This reduces splashing, reduces the risk of contamination and the need for cleaning.

FIG. 1 shows a schematic view of a pipette system in accordance with at least some embodiments of the invention. The automatic pipette of the present disclosure includes a module 10, the module 10 including at least one motor 101, an optional transmission102. At least one lead screw 103, at least one linear guide 104, at least one slide assembly 110 and locking hook 111, at least one cylinder 140 and piston 141, an ejector assembly 120, the ejector assembly 120 comprising a locking tab 121, an ejector spring 122 and control electronics. Ejector assembly 120 may also be referred to as an ejector slide or ejector assembly. In addition, the pipette includes a spindle 123, a spindle guide 130, a cavity extending lengthwise through the body, and a tip cone 124 (also referred to as a nose cone), which is typically slightly angled to accommodate the disposable tip 150. In the alternative, the tip cone may include an upper annular projection and a lower annular projection, the lower annular projection having a diameter smaller than a diameter of the upper annular projection. Furthermore, the pipette may comprise a spring-loaded pipette tip cone, i.e. an adjustable reinforcing element comprising a spring 115 and a mechanism 116 adapted to be stationary, e.g. Optiload^TMProvided is a system. Such a system provides a simple way to limit the maximum amount of force that can be used when performing tasks such as picking up pipette tips.

In some embodiments, the pipette component may include a rack and pinion mechanical linkage. The assembly may also include linear guides, shafts, linkages, springs, magnets, gears, mounts for components, and fluid handling components such as pipes or hoses. Additionally, the modules may include one or more of the following: a processor, a printed circuit board, a sensor such as a camera or an imaging device, a connector for wireless and wired communication, a connector for wireless and wired power transfer, a passive or active cooling element.

In a first exemplary embodiment of the invention, the electric motor 101 actuates the linear motion mechanism through a transmission 102, the transmission 102 comprising at least one of: gears, planetary gears, clutches, belts, timing belts, toothed belts, notched belts. The linear movement mechanism may for example comprise a lead screw 103 and/or a linear guide 104. The linear motion mechanism is coupled to the slide assembly 110, and thus to the piston 141. Thus, in the exemplary embodiment, actuating motor 101 in a first direction (i.e., clockwise or counterclockwise) causes slide assembly 110 to also move in the first direction. The same is true for the reversal of the motor, i.e., a reversal of the drive of the motor will cause the slide assembly to reverse. This causes the piston 141 to move within the cylinder 140. The pressure generated in the cylinder is used to dispense the liquid through the tip mandrel 123 and tip 150. The amount of liquid drawn and dispensed corresponds to the volume of air displaced.

Also in the first exemplary embodiment, the slide assembly 110 is linked to the ejector assembly 120 through a linkage or transmission. Thus, the ejector assembly is not always actuated when the slide assembly is actuated, which allows normal operation of the liquid dispensing without moving the ejector assembly. It is to be reiterated that the ejector assembly may be stationary in the normal (lowermost) position during liquid dispensing. In the exemplary embodiment shown in fig. 4, the ejector assembly is actuated as follows:

1. the motor 101 actuates the slide assembly 110 in a first direction (downward).

2. Slide assembly locking hook 111 passes over ejector assembly locking tab 121.

3. The motor 101 actuates the slide assembly 110 in a second direction (upward).

4. Slide assembly locking hook 111 contacts locking tab 121 of ejector assembly 120.

5. The slider assembly, which is connected to ejector assembly 120 via hook 111 and tab 121, pulls ejector assembly 120 in the second direction.

6. The ejector assembly 120 is connected to the tip spindle 123 and thus to the tip 150. The tip spindle 150 moves within the spindle guide 130 and thus, due to the upward movement of the slide assembly 110 and the ejector assembly 120, the tip spindle and the tip move in a second direction. Thus, the tip mandrel retracts into the module body 100.

7. The top surface of the tip 150 contacts the module body 100 and the resultant force removes the tip from the tip cone 124 (lower end of the spindle 123).

8. After removing the tip from the tip cone and optionally with a predetermined delay, the ejector assembly moves upward and into contact with a guide ramp that separates the hook 111 and tab 121 from each other.

9. The ejector assembly is returned to its lower position by at least one of gravity, magnetic force, or spring force.

The steps of the method are shown in fig. 7.

In some embodiments of the invention, including the first exemplary embodiment, tip removal is achieved by retracting the tip spindle 123 (connected to the ejector assembly 120) into the modular body 100 so that the upper edge or surface of the tip 150 contacts the modular body, and as the spindle 123 continues to be retracted, the tip is caught by the body 100 and removed from the spindle. In some embodiments, the suction head may contact a component that is fixedly or movably attached to the body. The suction head may contact a stationary contact surface, which refers to a feature fixedly attached to or part of the module body, such as at least one of: protrusion, recess, bearing, pin. In certain embodiments, the contact surface may be flexible, such as at least one of: a spring and a damper. Furthermore, the tip may be removed by: the spindle is first retracted until the tip is in contact with the body, as determined by calculations, force measurements, electrical conductivity measurements, distance measurements, etc., and then actuated further upwards. In some embodiments, tip removal may be performed by retracting the spindle at a first speed until the tip surface contacts the module body, and performing a jogging action by retracting the spindle at a second speed or speed profile, where the initial speed is lower and grows exponentially, or vice versa.

The body 100 of the pipette may remain stationary during removal of the tip. The tip spindle 123 is attached to the body via a spindle guide 130, which spindle guide 130 secures the spindle in the lateral direction, but allows up and down movement.

The movement of the ejector assembly may be caught by a spring, a magnet, a stationary assembly, or a combination thereof, e.g. the ejector assembly spring, or additionally or alternatively, a sliding assembly, before, during and after the tip is flicked off the tip spindle. In some embodiments, the ejector assembly in the upper position is captured by the slide assembly and the ejector spring. The upward movement of the tip may be arrested prior to nudging the tip. This allows the pipette tip to be retracted to an upper limit whilst retaining the pipette tip. This may be done for any reason, for example when a second parallel module is picking up a new tip, or when the module is not in use for some reason. The position of the ejector assembly when jammed may include an upper (retracted) position of the ejector assembly, or for example, 90% -99% of the range of motion of the ejector assembly. In another exemplary embodiment, the ejector assembly is positioned at 95% of the range of motion when jammed.

Figure 4 depicts a tip removal process. In the left-most image of fig. 3, the automatic pipette module is operated with the Optiload mechanism engaged. The slide assembly is not coupled to the ejector mechanism. In the middle image, the slide assembly is actuated to a lower position so that the locking hook passes around the locking tab. In the rightmost image, the slider assembly has been actuated upward, pulling the ejector assembly. The Optiload mechanism has disengaged. In the rightmost image, the tip spindle moves within the spindle guide due to the upward movement of the ejector assembly, and the disposable tip contacts the tip spindle guide and is removed.

In fig. 5, the process of decoupling the ejector assembly from the slide assembly is shown. Continuing with the process shown in FIG. 4, in the left-most image of FIG. 5, the pop-up assembly has been lifted by the slide assembly via the lock hook and lock tab. The Optiload system has been disengaged and is visible behind the ejector assembly. However, as shown, the locking assembly has been decoupled. The decoupling means is not shown in fig. 5, but according to embodiments described herein, for example, the decoupling element 129 has contacted the locking hook and locking tab. In the rightmost image of fig. 5, it can be seen that the ejector assembly has returned to the lower position and the Optiload system has engaged. The slide assembly is held in the upper position and the pipette module is ready for operation. In the exemplary embodiment, the ejector module is augmented with an Optiload system to facilitate picking up new tips. This process is described in further detail in the following paragraphs.

In at least some embodiments of the present disclosure, disengagement can be performed by utilizing the guide ramp 129. In the first embodiment, to restore the pipette to normal operation, the slide assembly 110 is actuated upward (attached to the ejector assembly 120 via the locking hook 111 and locking tab 121). At one point of upward movement, the ejector assembly, the slide assembly, or a combination of both, contact the guide 129, and the guide 129 separates the lock tab from the hook. The guide 129 may include at least one ramped surface, wherein the ejector assembly contacts the surface during movement and the ramping of the surface causes the locking tab to disengage from the hook.

In certain embodiments, the inclined surface is constituted by the ejector assembly or the sliding assembly or both assemblies, i.e. the guide is integrated into at least one assembly. Separation may be achieved by contacting a tab or hook, wherein the contact affects the path of movement of the tab or hook (as the slide assembly and ejector assembly are actuated upward even during guide contact). Restated, upward movement is used to actuate the components, and a stationary guide forces one of the locking tabs or hooks apart from one another. It will be appreciated that in an exemplary embodiment, the path of the tab or hook will not be linear after contacting the angled or curved guide. Instead, the path of the component will form a curve, while the corresponding component will continue in a different direction (e.g., a linear path). In some embodiments, the material of the tab or hook will deform or bend when the guide is in contact with the tab or hook. The space formed between the corresponding parts will allow the ejector assembly to bypass the hook and return to the lower normal position. Alternatively, in a configuration involving two guides, two locking members may contact the guide surface. The guide surface may comprise a grooved path, wherein the path may be linear or any type of curve in three dimensions.

In embodiments of the present disclosure, the guide ramp may be in any plane relative to the component. In an exemplary modification of the first embodiment, the locking hook is laterally moved (offset) with respect to the moving direction. This is a result of the combination of the upward movement and the guide surface. For clarity, referring to fig. 3, in the depth direction of the schematic, guide ramp 129 pushes or lifts lock hook 111 or lock tab 121. In an alternative variant, the guide ramp may be in either of the two remaining planes, i.e. the component may undergo rolling or pitching with respect to the direction of motion. To reiterate, the ramp of the guide may be oriented parallel to the ejector assembly, perpendicular to the ejector assembly, or parallel to or perpendicular to any relative rotation in a clockwise or counterclockwise direction. In another exemplary embodiment, the guide ramp is parallel to the ejector assembly and is rotated 60 ° clockwise on the longer axis.

In at least some embodiments of the present disclosure, disengagement can be performed by utilizing the guide features 126, 226 and at least one of the guide slots or guide slots 125, 225. The guide feature may be present on the ejector assembly, the slide assembly, or both assemblies. The guide features may be oriented at 90 ° relative to the direction of movement. The guidance feature may include at least one of: pin, spring, bearing. The guide features may be in contact with guide slots formed in the module body or in some other part. When the assembly is actuated upward, the guide feature travels within the guide slot. At some point of actuation, the guide slot will flex away from the direction of actuation, causing the components to separate. Then, according to embodiments described in the present disclosure, the assembly will return to the desired position.

The ejector assembly may additionally function as at least one of: a sensor mount, a conduit or connector for a sensor. In some embodiments, it may be beneficial for the ejector assembly to be constructed of a non-conductive material or to incorporate a path for signal transmission. This allows for conductive sensing of the condition of the tip (e.g. presence of the tip) as the tip mandrel is typically metal. In addition, this allows the use of electrically conductive pipette tips, such as carbon-filled pipette tips, for detecting the liquid level using, for example, capacitive measurement principles and detection of changes in, for example, the position of the pipette.

The locking tab of the ejector assembly may include a mechanical slot, leg, or the like, designed to allow controlled deformation of the tab. This controlled deformation, i.e., bending or twisting, can be utilized to allow the tab to allow passage of the locking hook. After this passage is completed, the resilience of the tab material returns the tab to its original shape, or the structure may be provided with a spring element to enhance the return action. For example, the upper surface of the tab may be sloped such that the hook is guided past the tab when moving downward. The tab will then bend to the side to allow the hook to pass. After the head of the hook passes the tab, the tab will return to its original shape. When the hook is reversed, the upper surface of the hook contacts the lower surface of the tab, forming a mechanical connection. As described above, this connection is used to move the ejector assembly to nudge the tip from the tip spindle.

In some embodiments according to the invention, the ejector assembly is flexibly locked in the lower (down) position at least by an ejector return spring. In embodiments according to the invention, the ejector return spring and Optiload mechanism allow for a desired degree of travel of the ejector assembly, and thus the tip spindle, as detailed elsewhere in this disclosure. There is also a shock absorber or shock damper at the lower limit of the ejector assembly because the ejector return spring allows for rapid movement.

In a variation of the first embodiment, the ejector assembly is coupled to the slide assembly by an electromagnet rather than a purely mechanical linkage. When actuated downward, the slide assembly approaches the upper portion of the ejector assembly and the coupling and subsequent decoupling is made by sending a signal to the magnet.

In other variations of the first exemplary embodiment, the automatic pipette module includes a spring 115 and a reinforcing element system 116, such as an Optiload mechanism. The purpose of this mechanism is to provide an arrangement in which the pipette tip spindle is flexibly locked in place. The Optiload mechanism functions as follows: when the ejector assembly is actuated to a relatively low position, the Optiload mechanism is moved to a position between the ejector mechanism and the upper portion of the module body so that the mechanism contacts the ejector assembly and the upper portion of the module body, as shown in fig. 3. This results in the stiffening element acting as a tip pick-up force limiter or damper, i.e. a significant portion of the force acting on the tip spindle is transferred to the stiffening element. Furthermore, the upper end of the reinforcing element is connected to the spring. This allows the ejector assembly and hence the tip spindle to reach the desired amount of vertical movement. The amount of vertical movement corresponds to the force exerted on the tip mandrel and so the user can pre-configure or configure these two values. In other exemplary embodiments, the adjustment of the Optiload travel distance (i.e., vertical travel distance) or required force may be facilitated by at least one of: a screw parallel to the direction of motion, a screw perpendicular to the direction of motion, a cylinder, an adjustable spring, a selectively deformable material.

It should be appreciated that the engagement of the Optiload mechanism may include vertical, horizontal or lateral movement, deformation, linear path, non-linear path of at least one component including the ejector assembly and the Optiload stiffening element. The Optiload system may be separated from the reinforcement location by various methods described later in this disclosure.

The use of an Optiload system may provide benefits to an automated pipette module. For example, when a tip is picked up (i.e., attached) to a tip spindle by a force fit, the forces exerted on the tip must also affect the internal mechanisms of the pipette module, such as the slide assembly and the actuators. Such effects may be detrimental to the component. However, when using an Optiload mechanism, the forces are absorbed and attenuated by the Optiload mechanism, thereby reducing wear on the components. The Optiload system provides consistent tip pick-up force regardless of the speed of the module during pick-up. Consistent pick-up forces will achieve optimal sealing of the tips, while the force required to separate pipette tips will be within reasonable limits. Another option for controlling the tip pick-up force is to control the Z-axis motion of the module during pick-up based on current data from, for example, a motor, or to provide a similar stiff spring system for the entire module. These methods are complex and require a high degree of accuracy and space to implement the system, as compared to the Optiload system described herein. Furthermore, in multi-channel modular solutions, single-channel springs are very complex to implement. Finally, a separate Optiload system for each module allows different sized tips to be used on the module and different spring constants to be used in each module.

In different embodiments, the Optiload system may be disengaged in different ways. For example, detachment can be accomplished by at least one of: guide ramps, magnets, electromagnets, motors, springs, electromagnets, and spring combinations. With respect to disengagement of the Optiload system, in embodiments of the present disclosure, similar to the guide ramps of the ejector assembly described above, the guide ramps may be in any plane relative to the components. In an alternative variant, the guide ramp may be in either of the two remaining planes, i.e. the component may undergo rolling or pitching with respect to the direction of motion. To reiterate, the ramp of the guide may be oriented parallel to the ejector assembly, perpendicular to the ejector assembly, or parallel to or perpendicular to any relative rotation in a clockwise or counterclockwise direction. In another exemplary embodiment, the guide ramp is parallel to the ejector assembly and is rotated 60 ° clockwise on the longer axis.

In a second exemplary embodiment, the lead screw is connected to the slide assembly by a link, wherein the link has at least two members and at least one joint. In this embodiment, the slide assembly is fixedly coupled to the ejector assembly. This connection allows for liquid dispensing using the normal range of motion of the lead screw. When the lead screw is actuated to the lowermost position, the link angle causes the ejector assembly to be actuated upwardly relative to the module body. This movement is highly controllable so that accurate removal of the cleaner head can be achieved, as in the other embodiments detailed herein. This embodiment may also be considered as a type of selective linkage because the motor may actuate the slide assembly without actuating the ejector assembly. One benefit of this embodiment is that the connecting rod allows for a shorter length of the lead screw than if the slide assembly were fixedly connected to the lead screw. Other benefits include the possibility to adjust the force ratio in order to obtain a maximum torque at the tip removal point, i.e. the torque is not constant over the entire range of motion, but increases at the tip removal point, which of course is the point where the extra force is most needed. In addition, friction losses are minimal in this type of structure. The second exemplary embodiment may also utilize the Optiload system previously described herein.

In some embodiments of the present disclosure, the clearance, play, or gap of the mechanism may be adjusted or controlled to improve the accuracy of the mechanical movement, liquid handling components, tip removal function, and ultimately the liquid dispensing function. These adjustments may be performed using at least one of: magnets, springs, control schemes including, but not limited to, feedback control and feed-forward control.

In some embodiments according to the present disclosure, sensor fusion is additionally or alternatively used to accurately detect linear motion of a mechanism comprising a pipette. This may also be compensated, adjusted and calibrated, which may be done based on variables such as temperature, humidity, etc. In some embodiments, the pipette module includes a liquid level detection function.

The invention detailed in this disclosure provides several technical benefits. The selective connection between the slide assembly and the ejector assembly allows the liquid discharge function to be operated without actuating the ejector assembly. Moreover, since only a part of the entire pipetting mechanism is actuated, a more precise operation of the cylinder is allowed, since the mass and inertia of the parts to be moved are reduced. The main advantage of the present invention is the compact size of the entire module, since no separate tip removal motor or electromechanical actuator is required. In addition, the use of the present invention means that no separate mechanism incorporated into the tip removal magazine is required, and therefore less force is exerted on the device.

Another advantage of the invention, which is described in detail in this disclosure, is that the control and gentle removal of the pipette tip is facilitated by a rigid and highly controllable mechanism, reducing the possibility of contamination as described below: with the present invention, the tip does not leave the tip holder or hit the vessel at high speed, which may scatter spray into the air, which may contaminate the sample or surface. Another advantage of the present invention is that the mechanism allows for the collection and storage of data such as force distribution and accurate tip removal position for the tip removal process. This data is stored during tip removal. This data is useful for analyzing the operation of the system, for example in reliability analysis. For example, if the tip removal always requires less and less force, this may indicate that the tip cone is problematic, as the tip may not be connected to the tip cone in future operations. Alternatively, in some cases, slippery substances (e.g., oil) may cover the tip cone, making it difficult to attach the tip to the tip cone. Predictive maintenance may be utilized to alert these types of problems in accordance with the present invention. The analysis may include comparing force profiles of the removal process, and the analysis may be offline or performed during operation.

The retractable mandrel in the embodiments disclosed herein also allows for selectively allowing the pipette to yield to an external force-i.e., if the pipette tip contacts a non-yielding surface, the ejector assembly will retract into the pipette body. This feature may help to avoid damaging or excessively wearing the pipette mechanism. The combination of the pop-up spring with the Optiload system, and more specifically the Optiload spring, helps to achieve this function. First, the ejector spring is compressed, and then, for example, after 0.2-1 mm, the Optiload spring is compressed. When the pipette mechanism engages the ejector assembly, it disengages the Optiload system to reduce the force opposing the actuation. The Optiload system can also detect when the pipette tip contacts a surface. More specifically, when the position of the ejector assembly is detected, the ejector assembly will move slightly when the pipette tip contacts the surface and this movement is sensed by the device. The Optiload spring prevents damage to the module during this operation.

Fig. 6 shows a third exemplary embodiment according to the present invention. For clarity, some components, such as the motor, transmission, etc., are omitted from the figures. This embodiment operates in a similar manner to the embodiments described above. It can be seen that these components interact in different positions than the other embodiments, for example, locking hook 211 is located near linear screw 203, and Optiload mechanism 216 is configured to interact in a slightly different position with ejector component 220 than the previous embodiments. Separation of ejector assembly 220 and slide assembly 210 is accomplished by groove 225 and disengagement feature 226. A recess 225 is formed in the housing or support portion of the automatic pipette. The breakaway feature is part of the ejector assembly and may include: pin, bearing, cylindrical feature. It can also be seen that ejector assembly 220 has a structure that allows for deformation, i.e., the arm with locking tab 221 can be deformed to the left of the image due to the design of the assembly, more specifically the gap between the arm and the body of the assembly is deformable. This embodiment, as well as the other embodiments mentioned previously, operate according to the method explained previously in this disclosure and in fig. 7.

Fig. 7 depicts steps of a method according to an embodiment of the present disclosure. The method comprises the following steps:

in step 501, the slide assembly is actuated such that at least a portion of the slide assembly moves past at least a portion of the ejector assembly,

in step 502, the slide assembly is retracted, such that the locking hook of the slide assembly is attached to the ejector assembly,

in step 503, the slide assembly is further retracted and the ejector assembly is retracted via the locking hook, such that the disposable tip attached to the ejector assembly by the tip cartridge is in contact with the at least one detachment or contact surface,

in step 504, the slide assembly is further retracted so that the movement of the disposable tip is arrested by the disengaging surface, as a result of which the tip is removed from the tip cartridge, and

in step 505, the slide assembly is retracted such that the ejector assembly is disengaged from the slide assembly by a disengagement mechanism comprising at least one of: the grooves, the surfaces, the features,

in step 506, the ejector assembly is returned to its starting position using at least one of a spring force, gravity or a magnetic force.

Additional benefits of the present invention include the ability to accurately measure spindle movement when picking up (attaching) pipette tips. During the pick-up process, the spring compression may be measured by incorporating sensors to monitor the movement of the ejector slide, which may calculate the force for attaching the pipette tip, as the relationship between displacement and force is known. The sensor may comprise at least one of: a linear hall element sensor, other magnetic technology sensor, optical sensor, or a mechanical switch for detecting the initial movement. Furthermore, this allows monitoring of the presence of the suction head during the suction of the suction head, since the cylinder will not move in the same way without the suction head.

It is to be understood that the disclosed embodiments of the invention are not limited to the particular structures, process steps, or materials disclosed herein, but extend to equivalents thereof as would be recognized by those ordinarily skilled in the relevant arts. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting.

Reference throughout this specification to one embodiment or variations means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Where a numerical value is referred to using a term such as about or substantially, the exact numerical value is also disclosed.

As used herein, a plurality of items, structural elements, compositional elements, and/or materials may be presented in a common list for convenience. However, these lists should be construed as though each member of the list is individually identified as a separate and unique member. Thus, no single member of such list should be construed as a de facto equivalent of any other member of the same list solely based on their presentation in a common group without indications to the contrary. In addition, reference may be made herein to various embodiments and examples of the invention and alternatives for various components thereof. It should be understood that such embodiments, examples, and alternatives are not to be construed as actual equivalents of each other, but are to be considered as independent and autonomous representations of the present invention.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In this description, numerous specific details are provided, such as examples of lengths, widths, shapes, etc., to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention can be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention.

While the above examples illustrate the principles of the invention in one or more particular applications, it will be apparent to those of ordinary skill in the art that numerous modifications in form, usage and implementation details may be made without the exercise of inventive faculty, and without departing from the principles and concepts of the invention. Accordingly, it is not intended that the invention be limited, except as by the claims set forth below.

The verbs "comprise" and "comprise" are used in this document as open-ended limitations that neither exclude nor require the presence of unrecited features. The features recited in the dependent claims may be freely combined with each other, unless explicitly stated otherwise. Furthermore, it should be understood that the use of "a" or "an" throughout this document, i.e., singular forms, does not exclude a plurality.

INDUSTRIAL APPLICABILITY

At least some embodiments of the invention find industrial application in liquid treatment systems.

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