Connection construction

Abstract

A connection construction (10), between a centrifuge rotor (12) and a drive shaft (14) of a laboratory centrifuge (100), allows one-handed operation that does not require any additional tools. The connection construction (10) is designed such that the locking mechanism (16, 48) is constantly guaranteed, preventing the jamming or blocking of the locking elements (16, 48). In addition, the user receives a reliable indication of a locked state (16, 48) by a clearly noticeable click.

Claims

1.-15. (canceled)

16. A connection construction (10) between a centrifuge rotor (12) and a drive shaft (14) of a centrifuge motor, the drive shaft (14) extending along a shaft axis (W), wherein a first locking element (16) is arranged on one of the elements of the centrifuge rotor (12) and the drive shaft (14), and a second locking element (48) is arranged on another of the elements of the centrifuge rotor (12) and the drive shaft (14), wherein the first locking element (16) is engaged with the second locking element (48) in a locked state of the connection and is disengaged in an unlocked state, wherein there is an actuating means (60) on one of the elements of centrifuge rotor (12) and drive shaft, an actuation of which causes the first locking element (16) to disengage from the second locking element (48), whereby the centrifuge rotor (12) is removable from the drive shaft (14).

17. The connection construction (10) according to claim 16, wherein the first locking element (16) is a lever having a lever arm which is movable in a plane parallel to the shaft axis (W).

18. The connection construction (10) according to claim 17, wherein the lever arm is movable in a plane that includes the shaft axis (W).

19. The connection construction (10) according to claim 17, wherein the lever (16), in an undeflected basic state, is arranged at an acute angle with respect to the shaft axis (W), and/or wherein the connection construction (10) is adapted such that the lever (16) is deflectable, due to centrifugal forces, in a first operating state in which the centrifuge rotor (12) is rotating relative to a second operating state in which the centrifuge rotor (12) not rotating, wherein the deflection relative to the second operating state is in the range of 1° to 5°.

20. The connection construction (10) according to claim 17, wherein the lever (16) is arranged at a joint (32), wherein the joint (32) is formed to be spring-loaded, and wherein the joint (32) is effected by an elastic, spring-loaded design of the lever (16) itself.

21. The connection construction (10) according to claim 16, wherein the first locking element (16) has a foot (26) that stands (28) on the second locking element (48).

22. The connection construction (10) according to claim 17, wherein the first locking element (16) has at least one chamfer (30), which serves as a locking aid, wherein the chamfer (30) lies parallel to a longitudinal extension of the lever (16).

23. The connection construction (10) according to claim 16, wherein the first locking element (16) is preloaded in a direction of engagement with the second locking element (48).

24. The connection construction (10) according to claim 16, wherein there are at least four first locking elements (16).

25. The connection construction (10) according to claim 16, wherein the first locking element (16) is arranged on the drive shaft (14).

26. The connection construction (10) according to claim 16, wherein the second locking element (48) is a projection on the centrifuge rotor (12), against which the first locking element (16) is supported in the locked state.

27. The connection construction (10) according to claim 16, wherein the actuating means (60) has a contact surface (72) for a mating contact surface (74) of the first locking element (16), wherein one of the two surfaces of contact surface and mating contact surface (74) has an inclined course in the actuating direction (B) of the actuating means (60), at least in the locked state of the connection construction (10), in such a manner such that actuation of the actuating means (60) causes the first locking element (16) to pivot, wherein the mating contact surface (74) runs in a manner inclined to the direction of the shaft axis (W) in the locked state.

28. The connection construction (10) according to claim 16, wherein the first locking element (16) and the second locking element (48) have contact surfaces (28, 48) that, in the locked state of the connection construction (10), bear against one another and effect the locking, wherein such contact surfaces (28, 48) are inclined with respect to a radial surface about the shaft axis (W).

29. The connection construction (10) according to claim 16, wherein the actuating means (60) is formed as a push button (62) that is preloaded (68) against the actuating direction (B).

30. The connection construction (10) according to claim 16, wherein the actuating means (60) is arranged on the centrifuge rotor (12).

31. The connection construction (10) according to claim 16, wherein the connection construction (10) provides a snap-in connection (16, 48), wherein the locking takes place within a clip connection (16, 48), which is designed to be releasable.

32. A connection (10) between a centrifuge rotor (12) and a drive shaft (14), comprising: a lever (16) arranged on the drive shaft (14), the lever having a lever arm which is movable in a plane that includes a shaft axis (W) of the drive shaft (14); a projection (48) formed on the centrifuge rotor (12), against which the lever (16) is supported in a locked state of the connection; a push button (62) arranged on the centrifuge rotor (12) that is preloaded (68) against an actuating direction (B), wherein the push button (62) has a contact surface (72) for a mating contact surface (74) of the lever, and wherein an actuation of the push button (62) causes the lever (16) to disengage from the projection on the centrifuge rotor (12), so that the centrifuge rotor (12) can be removed from the drive shaft (14).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] FIG. 1 shows the connection construction in a first preferred embodiment in the unlocked and separated state in section.

[0031] FIG. 2 shows the connection construction according to FIG. 1 in the locked state in section.

[0032] FIG. 3 shows the connection construction according to FIG. 1 in the unlocked state in section.

[0033] FIG. 4 shows the hub of the centrifuge rotor of the connection construction according to FIG. 1 in a perspective view in section.

[0034] FIG. 5 shows the drive shaft of the centrifuge rotor of the connection construction according to FIG. 1 in a perspective view.

[0035] FIG. 6 shows the connection construction according to FIG. 1 in a detail view in section.

[0036] FIG. 7 shows a laboratory centrifuge with the connection construction according to FIG. 1.

DETAILED DESCRIPTION

[0037] In FIGS. 1 to 6, the connection construction 10 is shown in various views in a preferred embodiment.

[0038] It can be seen that the connection construction 10 between a centrifuge rotor 12, which is only partially shown, and a drive shaft 14, which is only partially shown, of a centrifuge motor, which is not shown further, has eight spring elements 16 as first locking elements, which are arranged on a common spring crown 18.

[0039] This spring crown 18 is concentrically bolted to the drive shaft 14 by a bolt 20, such that the spring elements 16 extend equidistantly from a cylindrical section 22 of the drive shaft 14. Thereby, the spring elements 16 have projections 24 that form feet 26, the base 28 of which, in the relaxed state of the spring elements 16 shown in FIG. 6, is inclined relative to a radial plane with respect to shaft axis W. Further, the projections 24 have chamfers 30, which are inclined to the longitudinal extension of the respective spring element 16.

[0040] The spring elements 16 are connected to the spring crown 18 by joints 32, which allow an elastically reversible displacement of the feet 26 toward the shaft axis W. To provide elasticity, the spring elements 16 are integral with the spring crown 18 and made, for example, of a thermoplastic or a spring steel.

[0041] The spring elements 16 thus form lever arms acting as first locking elements, which are formed to pivot relative to the spring crown 18 via the respective joints 32.

[0042] A radially extending step 36 is located at the transition between the cylindrical section 22 and the conical section 34 of the drive shaft 14, the radial depth of which corresponds at least to the radial width of the feet 26, such that the feet 26 can be displaced completely onto or behind the course of the conical profile of the conical section 34.

[0043] The hub 38 of the centrifuge rotor 12 has a receiving space 39 for the drive shaft 14 with an incorporated internal hexagon 40, which corresponds to a corresponding external hexagon 42 of the drive shaft 14 and serves to transmit torque. Preferentially, such internal hexagon 40 is made of a harder material than the hub 38 and is fixed in this hub 38, for example screwed in or shrunk in.

[0044] The transmission of the torque from drive shaft 14 to centrifuge rotor 12 thus takes place via a positive-locking connection 40, 42. As an alternative to the hexagonal design shown, there could also be another polygonal design, for example an octagonal design, or the positive-locking connection could be made by a tongue-and-groove connection or also a drive pin-and-groove connection or other positive-locking connections that permit torque transmission.

[0045] The hub 38 further includes an inner cone 44, which corresponds to the conical section 34 of the drive shaft 14 and serves to provide a perfectly aligned fit of the centrifuge rotor 12 on the drive shaft 14 and a frictional fit. Such inner cone 44 merges into an inner cylinder 46, the diameter of which is at least equal to the outer diameter of the step 36, but preferably larger, wherein it is smaller than the outer diameter of the feet 26 in the relaxed state of the spring elements 16.

[0046] Further, above the inner cylinder 46, there is an annular step 48, which is bounded radially outwardly by a vertical edge 50, which belongs to a circumferential elevation 52 surrounding the step 48. This step 48 forms the second locking element. The edge 50 surrounds an inner diameter that is only slightly larger than the outer diameter of the feet 26 in the relaxed state. This ensures a secure locking while still allowing the projections 24 to strike the edge 50 during the sudden relaxation of the spring elements 16.

[0047] Furthermore, the hub 38 has a cylindrical cavity 54 above the elevation 52, which is bounded at the top by a lid-shaped closure element 56. In such closure element 56, which can be screwed into the hub 38, for example, there is an aperture 58, in which the actuating element 60 is received in a slidingly displaceable manner.

[0048] The actuating element 60 has a body 62 in the form of a push button 62, which has a collar 64 in its lower section that projects radially outwards and rests against the closure element 56 in the non-impressed state of the actuating element 60.

[0049] The elevation 52 merges radially outwardly into a recess 66. A coil spring 68 is arranged in such recess 66 on the one hand and between the section 69 of the body 62 projecting with respect to the collar 64 and the outer periphery of the cavity 54 on the other hand, and preloads the actuating element 60 in the upward direction, that is, against the actuating direction B of the actuating element 60. The coil spring 68 thereby provides the automatic return of the actuating element 60 from the actuated to the unactuated state.

[0050] This connection construction 10 now functions as follows:

[0051] In the state shown in FIG. 1, the centrifuge rotor 12 is placed with its hub 38 on the drive shaft 14 of the centrifuge motor. Thereby, the projections 24 of the spring elements 16 come into contact with the conical section 44 of the hub 38 by means of the chamfers 30, wherein the chamfers 30 and the conical section 44 thus provide a locking aid in that they prevent the projections 24 from tilting or catching on the hub 38.

[0052] At the same time, by steadily displacing the hub 38 further onto the drive shaft 14, the spring elements 16 are displaced inwardly to the extent that they can enter the inner cylinder 46, wherein, in extreme cases, the spring elements 16 can be swung in as far as the cylindrical section 22, such that the feet 26 can be displaced completely onto or behind the course of the conical profile of the conical section 34 and the step 36.

[0053] After the hub 38 has been pushed onto the drive shaft 14 to the extent that the projections 24 are no longer in contact with the inner cylinder 46, the spring elements 16 can relax, wherein the projections 24 are displaced outward on their own due to their preloading, until they are in contact with the edge 50. Thereby, the feet 26 rest against the step 48, such that the drive shaft 14 can no longer be pulled out of the hub 38. Due to the acting centrifugal forces, the spring elements 16 with the feet 26 are driven radially outwards relative to the shaft axis W during operation, such that such locking mechanism is self-locking during operation.

[0054] FIG. 6 shows that the projection 48 has a slope corresponding to the slope of the base 28 of the feet 26. This allows the feet 26 to shift early in the process of pushing the centrifuge rotor 12 onto the drive shaft 14, such that excessive vertical play between the feet 26 and the projection 48, and thus vertical “rattling” of hub 38 on drive shaft 14, is prevented.

[0055] When the spring elements 16 are suddenly released, the projections 24 strike the edge 50, causing a clearly audible clicking, which clearly signals to the user that the locking between the hub 38 and the drive shaft 14 has occurred securely (see FIGS. 2 and 6).

[0056] More specifically, each of the lever arms 16 is arranged at an acute angle with respect to the shaft axis (W) in the undeflected basic state shown in FIG. 1, wherein such angle is α=5°. In the locked state shown in FIG. 2, the angle is also α=5°, wherein such angle increases to 7° due to the centrifugal forces acting during operation, as a result of which the locking mechanism is self-locking during operation. In the unlocked state shown in FIG. 3, the angle is α=1°. This makes the locking mechanism particularly secure and easy to operate, and the click sound reliably indicates locking.

[0057] To release the locking mechanism, the push button 62 must be displaced in the actuating direction B, that is, downward. As a result, the contact surface 72 on the section 69 of the body 62 projecting with respect to the collar 64, which runs in the direction of the shaft axis W, is brought into contact with the mating contact surface 74, which is arranged on the spring element 16 and therefore runs at an angle with respect to the shaft axis W (see FIG. 3, the pivoting of the spring elements 16 inwards towards the cylindrical section 22 of the drive shaft 14 is not shown here for drawing-related reasons, but actually takes place).

[0058] As the push button 62 is depressed further in the actuating direction B, the mating contact surface 74 slides against the contact surface 72, by which a force is exerted on the spring elements 16, by which the feet 26 are displaced radially inward until they can be fully displaced onto or behind the course of the conical profile of the conical section 34. As a result, the feet 26 no longer rest against the step 48 and the hub 38 can be pulled off the drive shaft 14. The push button 62, after its release, slides upward driven by the coil spring 68 until the collar 64 rests against the closure element 56 (see FIG. 1).

[0059] It can also be seen that the aperture 58 includes a section 76 having a conical slope, which corresponds to a conical mating section 78 of the actuating element 60. As a result, the tilting of the actuating element 60 is effectively prevented when it is displaced by the coil spring 68 against the actuating direction B.

[0060] Although the first locking elements 16 have been described as lever arms 16 having projections 24 and feet 26 formed thereby, this comprises only one possible exemplary design. The spring elements 16 could also be formed without projections 24 and feet 26. This is advantageous if the spring elements 16 are made of spring steel, because, at that point, the design of the projections 24 and feet 26 is more complicated in terms of manufacturing than a design without such elements. Locking with the second locking element 48 would then be accomplished quite simply via straight extending ends (not shown) of the lever arms 16.

[0061] FIG. 7 shows a laboratory centrifuge 100 equipped with the connection construction 10.

[0062] It can be seen that such laboratory centrifuge 100 is formed in the usual manner, and thereby has a housing 102 with a control panel 106 arranged at its front side 104 and a lid 108, which is provided for closing the centrifuge container 110. A swing-out rotor 12 is arranged in the centrifuge container 110 as a centrifuge rotor, which can be driven by the drive shaft of a centrifuge motor (both not shown).

[0063] Although an example was shown above, with which spring elements 16 were used on the drive shaft 14, spring elements arranged in the hub can also be used.

[0064] Furthermore, the actuating element 60 also does not necessarily have to be arranged on the hub 38 of the centrifuge rotor 12; it can also be arranged on the drive shaft 14.

[0065] From the foregoing illustration, it has become clear that the present disclosure provides a connection construction 10 between the centrifuge rotor 12 and the drive shaft 14 of a laboratory centrifuge 100, which allows one-handed operation that does not require any additional tools. The connection construction 10 is constructed in such a manner that the locked state 16, 48 is always ensured, wherein the jamming or blocking of locking elements 16, 48 cannot take place. In addition, the user receives a reliable indication of a locked state 16, 48 by a clearly noticeable click.

[0066] Unless otherwise indicated, all features of the present disclosure can be freely combined. Also, unless otherwise indicated, the features described in the description of the figures can be freely combined with the other features. A limitation of individual features of the exemplary embodiments to the combination with other features of the exemplary embodiments is expressly not intended. In addition, the features of the subject matter can also be reformulated and used as method features, and the method features can be reformulated and used as features of the subject matter. Such a reformulation is thus automatically disclosed.

LIST OF REFERENCE SIGNS

[0067] 10 Connection construction according to a first preferred embodiment [0068] 12 Centrifuge rotor [0069] 14 Drive shaft [0070] 16 First locking elements, spring elements, lever arms [0071] 18 Spring crown [0072] 20 Screw [0073] 22 Cylindrical section of the drive shaft [0074] 24 Projections [0075] 26 Feet [0076] 28 Base, contact surface of the first connecting element 16 [0077] 30 Chamfer [0078] 32 Joints [0079] 34 Conical section of the drive shaft 14 [0080] 36 Radially running step [0081] 38 Hub of the centrifuge rotor 12 [0082] 39 Receiving space for the drive shaft 14 [0083] 40 Internal hexagon of the hub 38 [0084] 42 External hexagon of the drive shaft 14 [0085] 44 Inner cone of the hub 38 [0086] 46 Inner cylinder of the hub 38 [0087] 48 Annular step, second locking element, contact surface of the second connecting element 48 [0088] 50 Vertical edge [0089] 52 Circumferential elevation [0090] 54 Cylindrical cavity of hub 38 [0091] 56 Lid-shaped closure element [0092] 58 Aperture [0093] 60 Actuating element [0094] 62 Push button, body of the actuating element 60 [0095] 64 Collar [0096] 66 Recess [0097] 68 Coil spring [0098] 69 Section of the body 62 protruding with respect to the collar 64 [0099] 72 Contact surface [0100] 74 Mating contact surface [0101] 76 Section with conical slope of the aperture 58 [0102] 78 Conical counter section of the actuating element 60 [0103] 100 Laboratory centrifuge [0104] 102 Housing [0105] 104 Front side of the housing 102 [0106] 106 Control panel [0107] 108 Lid [0108] 110 Centrifuge container [0109] a Angle between lever 16 and shaft axis W [0110] B Actuating direction of the actuating element 60 [0111] W Shaft axis