PIPETTE TIP FAMILY COMPRISING PIPETTE TIPS FOR USE WITH PIPETTES OF A PIPETTE FAMILY AND PIPETTE FAMILY COMPRISING PIPETTES FOR USE WITH PIPETTE TIPS OF A PIPETTE TIP FAMILY
20220401945 · 2022-12-22
Assignee
Inventors
Cpc classification
B01L3/0275
PERFORMING OPERATIONS; TRANSPORTING
B01L2200/023
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
A pipette tip family includes a plurality of pipette tips each including a tip cylinder, each of the plurality of pipette tips further includes a hollow body including a bottom end and a top end such that the bottom end defines a tip opening and the top end defines a mounting opening, a seating region is configured to clamp to the spigot and a cylindrical plunger travel path is defined between the tip opening and the seating region, a tip plunger includes a plunger guided along the plunger travel path and a plunger rod comprising a top end, the plurality of pipette tips of each subfamily are configured to be used for pipetting with pipettes of a pipette type matched thereto and are not configured to be used with pipettes of a pipette type not matched thereto.
Claims
1-15. (canceled)
16. A pipette tip family comprising; a plurality of pipette tips configured to be used with different pipettes of a pipette family, wherein each of the pipettes comprise a spigot, wherein each of the plurality of pipette tips comprises, a tip cylinder comprising, a hollow body including a bottom end and a top end, wherein the bottom end defines a tip opening and the top end defines a mounting opening, a seating region configured to clamp to the spigot, and a cylindrical plunger travel path defined between the tip opening and the seating region, a tip plunger comprising, a plunger sealingly guided in the plunger travel path, and a plunger rod comprising a top end and projecting upward, wherein the plunger rod is configured to clamp to one of the pipettes, wherein the plurality of pipette tips are of a same subfamily when the top end of each plunger rod is in a deepest position of the tip plunger at a same position relative to the seating region, wherein the plurality of pipette tips are of different subfamilies when the top end of each plunger rod is in the deepest position of the tip plunger at different positions relative to the seating region, and wherein the plurality of pipette tips of each subfamily are configured to be used for pipetting with pipettes of a pipette type matched thereto and are not configured to be used with pipettes of a pipette type not matched thereto.
17. The pipette tip family according to claim 16, wherein the plurality of pipette tips of different tip types differ from one another by a nominal volume.
18. The pipette tip family according to claim 16, wherein each of the plurality of pipette tips comprises a collar with the mounting opening in the top end and the seating region on an inner circumference of the collar.
19. The pipette tip family according to claim 18, comprising at least one subfamily comprising a plurality of pipette tips of different tip types, wherein each of the plurality of pipette tips comprises a collar defining a characteristic height for a corresponding different tip type, wherein the plurality of pipette tips are configured to be clamped with at a seating region onto the inner circumference of the collar on the same clamping region of a spigot of a pipette of a same pipette type, wherein the collars of each of the plurality of pipette tips stand at different heights on the spigot.
20. The pipette tip family according to claim 17, wherein the nominal volumes of each of the plurality of pipette tips of different tip types of at least one subfamily differ from one another by one or more decimal powers.
21. The pipette tip family according to claim 16, wherein the seating region of the plurality of pipette tips comprises one of a circumferential bead on an inner circumference of the tip cylinder and a circumferential annular groove on the inner circumference of the tip cylinder configured for snap-fit connection with the spigot of a pipette.
22. The pipette tip family according to claim 21, wherein the plurality of pipette tips comprise at least one pipette tip of at least a first pipette tip type of a first subfamily, wherein when the tip plunger is in a deepest position, the top end of the plunger rod is positioned in a first position above a circumferential bead on the inner circumference of the tip cylinder for use with pipettes matched to a first pipette type, wherein the plurality of pipette tips comprise at least one pipette tip of at least a second tip type of a second subfamily, wherein when in a deepest position of the tip plunger, the top end of the plunger rod is positioned in a second position below the circumferential bead arranged on the inner circumference of the tip cylinder for use with pipettes matched to a second pipette type, wherein the plurality of pipette tips comprise and at least one pipette tip of a third tip type of a third subfamily, wherein when the tip plunger is in a deepest position of the tip plunger, the top end of the plunger rod is arranged in a third position between the first and second positions for use with pipettes matched to a third pipette type.
23. The pipette tip family according to claim 22, wherein the one or more pipette tips of the first subfamily comprise nominal volumes of 10 μl and 100 μl, wherein the one or more pipette tips of the second subfamily comprise nominal volumes of 25 μl and 250 μl and are configured for use with the second pipette type, and wherein the one or more pipette tips of the third subfamily comprise a nominal volume of 1000 μl and are configured for use with pipettes of a third pipette type.
24. The pipette tip family according to claim 16, wherein at least one of, (1) the plunger rods comprise a circumferential clamping groove below the top end configured to securely clamping at least one clamping element disposed on a stroke rod, (2) the plunger rods comprise a lower rod part comprising a larger outer diameter configured to securely clamp a clamping element positioned on the stroke rod and an upper rod part comprising a smaller diameter than the lower rod part so that the upper rod part cannot be securely clamped by the clamping element of the stroke rod, and (3) below one of the clamping groove and the lower rod part, the tip plungers comprise a hard stop configured to prevents the plunger rod from being pressed so deeply into the seat of the stroke rod.
25. A pipette family comprising pipettes of different pipette types for use with pipette tips of different tip types of a pipette tip family, each pipette comprising: a pipette housing including a top end and a bottom end; a spigot extending in a longitudinal direction and positioned at the bottom end of the pipette housing, the spigot comprising, an outer circumference, a clamping region on the outer circumference configured for clamping a pipette tip having a mounting opening, and a through-bore configured to receive a plunger rod of a tip plunger of the pipette tip; a drive apparatus comprising, a stroke rod oriented to the through-bore and configured to be displaceably guided in the longitudinal direction of the spigot, wherein the drive apparatus further defines an axial bore and a hole configured to at least partially receive the tip plunger, a clamping apparatus configured to securely clamp the tip plunger in the axial bore, and an operating element configured to protrude from the pipette housing and be displaceable relative to the pipette housing, wherein the operating element is coupled to the stroke rod and configured to displace a plunger of the tip plunger in a tip cylinder such that he plunger is sealingly guided along a plunger travel path between a tip opening in the bottom end and a seating region of the tip cylinder; and an elongated first sensing element configured to be upwardly displaced inside the axial bore of the stroke rod in the longitudinal direction of the spigot when the operating element is unloaded, wherein the elongated first sensing element Is configured for sensing the top end of a tip plunger inserted into the axial bore of the pipette tip and pushed onto the spigot at a mounting opening, and a control unit coupled to the elongated first sensing element, the control unit configured to place the pipette into a state enabling pipetting upon sensing a plunger rod of a pipette tip of a subfamily of the pipette tip family that is matched to a pipette type of the pipette, wherein when the top ends of the plunger rods are in a deepest position, the top ends of the plunger rods have a same position relative to the seating region, and wherein to place the pipette into a state that inhibits pipetting upon sensing a plunger rod of a pipette tip of a subfamily not matched to the pipette type, wherein when the top ends of the plunger rods are in the deepest position, the top ends of the plunger rods have different positions relative to the seating region than the pipette tips of the subfamily matched to the pipette tip.
26. The pipette family according to claim 25, wherein the control unit of each pipette is configured to at least one of; (i) place the drive apparatus into a state enabling pipetting and to permit the secure clamping of the pipette tip to the spigot and stroke rod upon sensing the plunger rod comprising a length that matches a length of a plunger rod of a pipette tip of a subfamily matched to the pipette; and (ii) place the drive apparatus into a state that inhibits pipetting upon sensing a plunger rod comprising a length that is shorter than the plunger rod of a pipette tip of a subfamily matched to the pipette; and (iii) prevent the secure clamping of the pipette tip to at least one of the spigot and stroke rod upon sensing a plunger rod that is longer than the plunger rod of the pipette tip of the subfamily matched to the pipette.
27. The pipette family according to claim 26, wherein the control unit of each pipette further comprises: an ejection apparatus comprising a curved support including a circumference and rotatably mounted within the pipette housing; and a second sensing element positioned on the elongated first sensing element, where in the second sensing element is displaceably guided in the longitudinal direction of the spigot within the pipette housing, and wherein the second sensing element is configured to be guided along a first curve on the circumference of the curved support, wherein the operating element is connected to the curved support and configured to project from the pipette housing and rotate relative to the pipette housing, wherein when the operating element is rotated from a pipetting position to and ejection position, the ejection apparatus is configured to rotate the curved support, wherein the first curve displaces the second sensing element downward such that the elongated first sensing element pushes off a pipette tip held on the spigot, and wherein when a plunger rod that is shorter than the plunger rod length of a pipette tip of a subfamily matched to the pipette is sensed by the elongated first sensing element, rotation of the operating element from an ejection position to a pipetting position is inhibited such that pipetting is inhibited.
28. The pipette family according to claim 27, wherein the control unit of each pipette further comprises a form-fitting connection between the spigot and a pipette tip such that the pipette tip is configured to at least one of, be installed onto the spigot while elastically constricting the spigot, and be installed onto the spigot while elastically expanding the pipette tip before the form-fitting connection to the spigot.
29. The pipette family according to claim 28, wherein the control unit of each pipette further comprises: a locking apparatus comprising a locking sleeve arranged concentric to at least one of the spigot and the stroke rod; a control rod configured to project upward from the locking sleeve, wherein the locking sleeve is configured to be displaceably guided along the longitudinal direction of the spigot in the pipette housing; a third sensing element configured to be guided along a second curve on the circumference of the curved support and further configured to project from the control rod, wherein the third sensing element is configured such that at least one of, the locking sleeve is in a locked position and limits the spigot on an inside when an arrangement of the operating element in the pipetting position is sensed, the pipette tip is limited on an outside, the stoke rod is limited on the outside such that the locking sleeve inhibits the pipette tip from form-fittingly connecting to the spigot, and the stroke rod detaches from the spigot.
30. The pipette family according to claim 29, wherein rotation of the operating element from the pipetting position to the ejection position results in at least one of, (1) the locking sleeve can be displaced upward so that the spigot, and (2) the pipette tip is at least partially exposed and the elongated first sensing element pushes the pipette tip off of the spigot, and wherein when the elongated first sensing element senses that the plunger rod is longer than the plunger rod of a pipette tip of a subfamily matched to the pipette, the locking sleeve is inhibited from being displaced to the locked position such that secure clamping of the pipette tip to the pipette is inhibited.
31. The pipette family according to claim 25, wherein the control unit of each pipette further comprises a hard stop, and wherein when a collar of a pipette tip is longer than collars of the pipette tips of a subfamily matched to the pipette, the hard stop is configured to inhibit secure clamping of the pipette tip to the pipette.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] The invention is explained below based on the accompanying drawings of an exemplary embodiment. In the drawings:
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DETAILED DESCRIPTION OF THE INVENTION
[0080] In the present application, the expressions “upper” and “lower” as well as “vertical” and “horizontal” and terms derived therefrom such as “above” and “below”, “standing upright” and “upside down” as well as “over each other” refer to an arrangement of the pipette wherein the spigot is oriented vertically, and is located on the downwardly facing end of the pipette housing. With regard to the pipette tip, these expressions refer to a vertical orientation of the middle axis of the pipette tip, wherein the tip opening is arranged at the bottom, and the mounting opening is arranged at the top.
[0081] According to
[0082] The upper spigot section 6 has a smaller cone angle than the lower spigot section 7. An annular groove 8 runs around the outer circumference of the spigot 4 between the upper spigot section 6 and the lower spigot section 7. The upper spigot section 6, the annular groove 8 and the lower spigot section 7 form a first means for the form-fit connection of the pipette to a pipette tip. The annular groove 8 forms a clamping region 9 for a corresponding bead of a pipette tip. Furthermore, the spigot 4 has slots 10, 11, preferably three, running in its longitudinal direction that are distributed at equal distances on the circumference of the spigot 4. The slots 10, 11 extend from the bottom end over the entire length of the spigot 4.
[0083] According to
[0084] According to
[0085] According to
[0086] According to
[0087] Turning back to
[0088] According to
[0089] The rotating sleeve 33 has parallel cutouts 34, 35 on two diametrically opposite sides to its rotational axis which extend from the upper edge of the rotating sleeve 33 and terminate at a distance from its lower edge. Below the cutouts, the rotating sleeve 33 accordingly consists of an annular base 36, and it also consists of two diametrically opposite sectors 37, 38 of an annulus that border the two cutouts 34, 35 on the side.
[0090] A first curve 39 and a second curve 40 are arranged on the outer circumference of the annular base 36 of the rotating sleeve 33. The first curve 39 is configured as a first groove 41 in the form of an inverted (upside down) Y. The vertical part 42 of the Y extends far upward to a sector 37 just short of the upper edge of the sector 37. The second curve 40 is a second groove 43 in the outer circumference of the base 36 of the rotating sleeve 33 in the form of an upright V. The first curve 39 and the second curve 40 are arranged offset 90 degrees relative to each other on the circumference of the rotating sleeve. The first curve 39 and the second curve 40 each extend over an angular range of less than 90 degrees over the circumference of the rotating sleeve 33.
[0091] According to
[0092] According to
[0093] According to
[0094] According to
[0095] The operating element 18 with the first curved slot 22 is pushed onto the sector 37 of the rotating sleeve 33 in which sector the first groove 41 extends. According to
[0096] The rotating sleeve 33 and the locking sleeve 51 as well as the operating element 18 are for example made of one or more rigid plastics and/or of metal. The rotating sleeve 33, the support ring 56, the operating element 18 and/or the locking sleeve 51 are preferably each configured as a single part. An operating button of the operating element 18 can also be produced from an elastic or soft-elastic plastic or rubber.
[0097] According to
[0098] Opposite the effect of a spring apparatus, the operating lever 19 can be displaced downward, starting from the support ring 56, along the second housing slot 612, wherein it slides with the first curved slot 22 on the sector 37 of the rotating sleeve 33. After being relieved, the spring apparatus independently displaces the operating lever 19 back upward.
[0099] A sleeve-shaped fourth sensing element 62 is guided on the outside of the shaft 3. A spring apparatus in the form of a helical spring 63 guided on the shaft abuts the bottom of the pipette housing 2 and the top of the fourth sensing element 62. By means of the helical spring 63, the fourth sensing element 62 is pressed from above against a hard stop element on the shaft 3 or the spigot 4.
[0100] An adjusting knob 64 for adjusting a dosing volume is arranged on the top of the pipette housing 2. The dosing volume can be adjusted by turning the adjusting knob 64. A counter 65 arranged thereunder in the pipette housing 2 indicates the adjusted dosing volume in each case. The adjusting knob 64 and/or the counter 65 is coupled to the transmission mechanism 15. The transmission mechanism 15 is configured to change the stroke of the stroke rod 17 corresponding to the particular adjusted dosing volume, which stroke is executed by the downward displacement of the operating element 18.
[0101] According to
[0102] Below the connection region 73, the tubular body 69 has a cylindrical plunger travel path 77. Thereunder, the tubular body 69 has a downwardly tapering tip section 78 with the shape of a conical frustum. The tip section 78 is shown in
[0103] A tip plunger 68 is inserted into the tubular body 69. This comprises a plunger 79 that is guided in the plunger travel path 77. A plunger rod 80 projects upward from the plunger 79 and has a smaller diameter than the plunger 79. The plunger rod 80 has a lower rod section 81 with a larger diameter and above this, an upper rod section 82 with a diameter that is smaller relative to the lower rod section 81. On the lower rod section 81, the plunger rod 80 has a circumferential clamping groove 83 on the outside.
[0104] According to
[0105] Shoving the tip plunger 68.1 to 68.3 into the tip cylinder 67.1 to 67.3 is limited in the smaller pipette tips 66.1 to 66.3 having a nominal volume of 10, 25 and 100 μl by a disc 84.1 to 84.3 arranged on the tip plunger 68.1 to 68.3 between the plunger rod 80.1 to 80.3 and the plunger 79.1 to 79.3 sitting on a ledge 85.1 to 85.3 in the tip cylinder 67.1 to 67.3. The two larger pipette tips 66.4, 66.5 having a nominal volume of 250 μl and 1000 μl also have a disc 84.4, 84.5 that serves to center the tip plunger 68.4, 68.5 in the tip cylinder 67.4, 67.5. In the pipette tips 66.4 to 66.5, the deepest position of the tip plunger 68.4 to 68.5 is (additionally) defined by the placing of a conical plunger 79.4 to 79.5 on a conical tip section 78.4 to 78.5 on the bottom end of the tip cylinder 67.3 to 67.5.
[0106] The different nominal volumes are identified by the different height of the collar 72.1 to 72.5 of the tip cylinder 67.1 to 67.5. The height of the collar 72.1 to 72.5 is given as the distance from the bead 75.1 to 75.5 to the upper edge of the collar.
[0107] The pipette tips 66.1, 66.3 having a nominal volume of 10 μl and 100 μl form a first subfamily 86.1. In these, when the tip plunger 68.1, 68.3 is at its deepest position, the top ends of the plunger rods 80.1, 80.3 occupy the same positions above the seating region 87.1, 87.3 that are defined by the circumferential bead 75.1, 75.3.
[0108] The pipette tips 66.2, 66.4 having a nominal volume of 25 μl and 250 μl form a second subfamily 86.2. In these, when the tip plunger 68.2, 68.4 is at its deepest position, the top ends of the plunger rods 80.2, 80.4 have the same position below the seating region 87.2, 87.4 that are defined by the beads 75.2, 75.4.
[0109] The pipette tip 66.5 having a nominal volume of 1000 μl forms a third subfamily 86.3. This only consists of the single family member. In this subfamily 86.3, when the tip plunger 68.5 is at its deepest position, the top end of the plunger rod 80.5 is arranged at approximately the level of the upper edge of the seating region 87.5 that is defined by the bead 75.5.
[0110] According to
[0111] In
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[0113] According to
[0114] According to
[0115] According to
[0116] According to
[0117] According to
[0118] According to
[0119] In
[0120] According to
[0121] According to
[0122] According to
[0123] Furthermore, the plunger rods 80.1, 80.3 and 80.5 of the pipette tips 66.1, 66.3 and 66.5 are each too long so that pipetting is not possible for the reasons stated with regard to
[0124] The ejection apparatus 31 and the locking apparatus 50 are components of a mechanical control apparatus 88 coupled to the first sensing element 44, which control apparatus 88 places the pipette 1 into a state that enables pipetting or does not enable pipetting depending on the sensed plunger rod 80.
[0125] The pipette 1 can be used as follows:
[0126] According to
[0127] According to
[0128] The fourth sensing element 62 is pressed against the upper edge of the pipette tip 66 by the pretensioned helical spring 63. The position of the fourth sensing element 62 depends on the height of the collar 72 of the mounted pipette tip 66 or on the length by which the collar 72 projects relative to the bead 75. The height of the collar 72 is characteristic for the nominal volume of the pipette tip 66 used. The fourth sensing element 62 is coupled to a panel or another range adjusting apparatus on the counter 65 by a slider omitted in the drawing or another transmission apparatus. Consequently, the counter 65 displays the volume that can be pipetted with the respective mounted pipette tip 66 considering the stroke adjusted by means of the operating element 18. Embodiments of the pipette that have a sensing apparatus for sensing the height of the collar of the pipette tip and embodiments of a pipette tip family wherein the pipette tips of different types (e.g., having different nominal volumes) have collars of different heights are described in the European Patent Application EP 18 168 763.3.
[0129] To draw liquid, the pipette 1 is immersed in a liquid with the bottom end of the pipette tip 66 held thereon. Then the operating element 18 is again pressed downward. This movement is converted by the transmission apparatus 15 into a stroke movement of the stroke rod 17. As a result, the tip plunger 68 is displaced upward. In so doing, the rod part 82 entrains the first sensing element 44 so that the first guide pin 49 slides upward in the vertical part 42 of the Y-shaped first groove 41. During this, the locking sleeve 45 retains its position. This is shown in
[0130] Once the operating element 18 has executed the set stroke, the pipette tip 66 is filled with a certain quantity of liquid. Then the operating element 18 is relieved and is displaced back upward by the spring apparatus up to the support ring 56. To discharge this quantity of liquid, the pipette 1 with the pipette tip 66 can be oriented to another vessel. By again pressing the operating element 18 downward, the stroke rod 17 is displaced downward, and the quantity of liquid is discharged. In so doing, the first guide pin 49 slides downward to the node point of the first groove 41.
[0131] The stroke executed by the operating element 18 while drawing and discharging liquid depends on the set quantity of liquid. Drawing and discharging liquid can be performed multiple times.
[0132] To eject the pipette tip 66, the operating element 18 in the starting position is swung to the right or to the left to an ejection position. In this way, the rotating sleeve 33 is rotated so that the second groove 43 displaces the second guide pin 55, and therefore the locking sleeve 51, upward until the locking sleeve 51 has released the spigot 4 to such an extent that it can be deformed radially inward. To accomplish this, preferably the locking sleeve 51 is pulled out of the through-bore 5. Furthermore, by the rotation of the rotating sleeve 33, the first guide pin 49 is displaced downward in one of the two lateral sections of the lower part of the first groove 41 so that the first sensing element 44 presses against the tip plunger 68 that is supported at the bottom at the tip section 78. In so doing, the bead 75 exerts a radial force on the spigot 4 so to constrict it, and the form-fit connection between pipette tip 66 and spigot 4 is released. In this way, the pipette tip 66 is released from the spigot 4. This is shown in
[0133] Once the used pipette tip 66 is released from the spigot 4, a new pipette tip 66 can be connected to the spigot 4. To accomplish this, the pipette 1 can be inserted with the spigot 4 into the mounting opening 71 of a pipette tip 66 provided in a support. In so doing, the fourth sensing element 62 is displaced upward and pretensions the helical spring 63. In this way, the display of the counter 65 is set to the mounted pipette tip 66. Furthermore, the upper rod part 82 presses against the bottom of the first sensing element 44 so that the first guide pin 49 slides up to the first branching point of the first groove 41. In so doing, the rotating sleeve 33 is rotated in the pipette housing 2 until the operating element 18 is located in the pipetting position. At the same time, the second guide pin 55 slides in the second groove 43 to the low point. This displaces the locking sleeve 51 into the locked position in
[0134] Connecting the tip plunger 68 to the stroke rod 17 and pipetting can be carried out in the above-described manner.
[0135]
[0136] The hard stop 89.1 is positioned so that the plunger rod 80.6 can be shoved far enough into the seat 27 that the clamping spring 30 engages in the clamping groove 83.6. By arranging the hard stop 89.1 on the edge of the hole 25, the plunger rod 80.6 is prevented from being shoved farther into the seat 27. It is only possible to pull the tip plunger 68.6 out of the seat 27 by overcoming the clamping force of the clamping spring 30. Consequently, the tip plunger 68.6 is held by the stroke rod 17 so that it cannot be shifted upwards or downwards. This prevents pipetting errors while drawing and discharging the liquid.
[0137] According to
[0138] The pipette tips 66.7 to 66.11 substantially differ from the pipette tips 66.1 to 66.5 in that the plunger rods 80.7 to 80.11 have wide annular grooves 83.7 to 83.11 instead of the narrow clamping grooves 83.1 to 83.5. Furthermore, the plunger rods 80.7 to 80.11 have clamping grooves 83.7 to 83.11 at the bottom end of the lower rod part 81.7 to 81.11, each of which has a hard stop 89.2 to 89.6. Each hard stop 89.2 to 89.6 simultaneously forms a lower delimitation of the annular groove 83.7 to 83.11 arranged above it. The hard stops 89.2 to 89.6 are each formed by the top of a conical section 90.2 to 90.6 expanding upward. Alternatively, the hard stops 89.2 to 89.6 are formed by the top of a disc or by a plurality of outwardly projecting projections distributed at the same height over the circumference of the plunger rod 80.7 to 80.11.
[0139] The tip plungers 68.7 to 68.11 are configured so that they can be form-fittingly connected to a stroke rod 17 that has a plurality of slots on the bottom end, wherein the segments of the stroke rod 17 remaining between the slots form inwardly projecting hooks that are formed and dimensioned to snap into the clamping grooves 83.7 to 83.11 on the plunger rods 80.7 to 80.11. A stroke rod 17 and its interaction with a tip plunger is described in particular in
[0140] The plunger rods 80.7 to 80.11 can be inserted into the axial bore 24 of the stroke rod 17 until the hard stop 89.2 to 89.6 abuts the bottom end of the stroke rod. The hooks then engage in the annular groove 83.7 to 83.11. This prevents the plunger rod 80.7 to 80.11 from being inserted further into the stroke rod. It is only possible to pull the tip plunger 68.7 to 68.11 out of the seat by overcoming the spring force of the bottom end of the stroke rod 17. If the pipette is equipped with a locking sleeve according to DE 10 2020 118 587.1, the plunger can only be released from the stroke rod 17 if the locking sleeve is displaced upward from the locked position to a released position. This holds the tip plunger 68.7 to 68.11 immovably on the stroke rod 17 and prevents pipetting errors while drawing and discharging the fluid.
[0141] As in the pipette tips in
[0142] As in the pipette tips in
[0143] Furthermore, the pipette tips 66.8, 66.10 having a nominal volume of 25 μl and 250 μl form a second subfamily 86.5 wherein the top ends of the plunger rods 80.8, 80.10 in the deepest position of the tip plunger 68.8, 68.10 occupy the same position at the same height as the bead 75.8, 75.10.
[0144] Finally, the pipette tip 66.11 having a nominal volume of 1,000 μl forms a third subfamily 86.6 that only consists of a single family member. In this subfamily 86.6, the top end of the plunger rod 80.11 in the deepest position of the tip plunger 68.11 is located above the bead 75.11, specifically only about half as far above the bead as the pipette tips 66.7, 66.9 of the subfamily 86.4.
LIST OF REFERENCE SIGNS
[0145] 1 Pipette [0146] 2 Pipette housing [0147] 3 Shaft [0148] 4 Spigot [0149] 5 Through-bore [0150] 6 Upper spigot section [0151] 7 Lower spigot section [0152] 8 Annular groove [0153] 9 Clamping region [0154] 10 Slot [0155] 11 Slot [0156] 12 Drive direction [0157] 13 Transmission element [0158] 14 Transmission rod [0159] 15 Transmission mechanism [0160] 16 Drive element [0161] 17 Stroke rod [0162] 18 Operating element [0163] 19 Operating lever [0164] 20 Bar [0165] 21 Support plate [0166] 22 First curved slot [0167] 23 First edge cutout [0168] 24 Axial bore [0169] 25 Hole [0170] 26 Longitudinal slot [0171] 27 Seat [0172] 28 Clamping spring groove [0173] 29.1 Clamping slot [0174] 29.2 Clamping slot [0175] 30 Clamping spring [0176] 31 Ejection apparatus [0177] 32 Curved support [0178] 33 Rotating sleeve [0179] 34 Cutout [0180] 35 Cutout [0181] 36 Base [0182] 37 Sector [0183] 38 Sector [0184] 39 First curve [0185] 40 Second curve [0186] 41 First groove [0187] 42 Vertical part [0188] 43 Second groove [0189] 44 First sensing element [0190] 45 Upper ejection rod section [0191] 46 Lower ejection rod section [0192] 47 Connecting rod section [0193] 48 Second sensing element [0194] 49 First guide pin [0195] 50 Locking apparatus [0196] 51 Locking sleeve [0197] 52 Control rod [0198] 53 Second connecting rod section [0199] 54 Third sensing element [0200] 55 Second guide pin [0201] 56 Support ring [0202] 57 Jacket [0203] 58 Second curved slot [0204] 59 Second edge cutout [0205] 60 First housing slot [0206] 61 Second housing slot [0207] 62 Fourth sensing element [0208] 63 Helical spring [0209] 64 Adjustment knob [0210] 65 Counter [0211] 66 Pipette tip [0212] 67 Tip cylinder [0213] 68 Tip plunger [0214] 69 Body [0215] 70 Tip opening [0216] 71 Mounting opening [0217] 72 Collar [0218] 73 Connection region [0219] 74 Lower connection section [0220] 75 Bead [0221] 76 Upper connection section [0222] 77 Plunger travel path [0223] 78 Tip section [0224] 79 Plunger [0225] 80 Plunger rod [0226] 81 Lower rod part [0227] 82 Upper rod part [0228] 83 Clamping groove [0229] 84 Disc [0230] 85 Ledge [0231] 86 Subfamily [0232] 87 Seating region [0233] 88 Control apparatus [0234] 89 Hard stop [0235] 90 Conical section