Compressible and expandable blade for a fluid pump

Abstract

Compressible and expandable blade (2) for the rotor of a fluid pump, characterized by at least two lamellae (3, 4, 5, 12, 13, 14, 15, 16, 17, 20, 21, 22, 23, 24, 25, 28, 29) which are arranged next to one another and are each pivotable relative to a rotational axis (1a) of the rotor and movable relative to one another and, in the expanded state, bear against one another in such a way that together they form a continuous blade surface, wherein the at least two lamellae (43, 44, 45) arranged next to one another belong to different rotor segments (40), wherein a rotor segment (40) contains at least one lamella and a hub segment (46).

Description

[0001] The present invention lies in the field of mechanics or micromechanics and can be used advantageously in particular in medical technology.

[0002] The invention relates to a pump blade and its design. This involves a pump with a rotor, the rotor being compressible and expandable to allow the overall dimensions of the pump to be changed if necessary. This allows the pump to be pushed through difficult-to-access openings or into narrow pipe systems. For this purpose, it is first compressed and then expanded again after being brought to the site of use.

[0003] Such a pump is particularly advantageous in medical technology in the field of heart pumps or other pumps for body fluids that are usually used with catheters.

[0004] Various types of micropumps are known in the medical technology field. These can be introduced into a patient's body in a compressed state using a catheter through a body vessel and expanded on-site. To create the appropriate radial compressibility and expandability, various effects can be used in the design and construction of the pump housing and pump rotor, such as the use of so-called shape-memory alloys, which change their shape depending on the ambient temperature, or the provision of specific transmission mechanisms that allow the pump diameter to be specifically controlled.

[0005] DE 10 2004 054 714 A1 discloses a solution in which both the impeller of a micropump and its housing are manipulated by a mutual axial displacement of the pump drive shaft relative to a catheter. This changes the housing between a compressed and an expanded state.

[0006] From the patent document WO 00 / 2003103745 A2 a system is known in which the pump housing is also radially expanded by an axial relative movement of two components against each other.

[0007] US patent US 7393181 discloses a rotor whose blade can be divided into several sub-blades or rows of sub-blades for improved compressibility / foldability. This subdivision makes the individual sub-blades smaller than a single-piece blade and almost flat, making them easy to roll up. However, the ability to divide them is limited by the inherent stability of the sub-blades that must be ensured.

[0008] Against the background of the prior art, the present invention is based on the object of producing a rotor or a blade for such a rotor that is as simple and cost-effective to manufacture as possible. The primary objective is to achieve high compressibility with the least possible effort, so that the pump rotor can be compressed without significant external resistance when pulling the pump out of the vessel. Furthermore, the corresponding pump should be designed to be powerful and low-consumption.

[0009] The object is achieved according to the invention with the features of patent claim 1.

[0010] The invention provides a blade with a plurality of lamellae which are arranged next to one another, are movable relative to one another and are pivotable relative to a rotational axis of the rotor, wherein the lamellae, in the expanded state of the blade, abut one another in such a way that together they form a continuous blade surface.

[0011] Such lamellae can be easily pivoted individually into a space-saving state due to their pivotability and, in the swung-out, expanded state of the blade or rotor, form a closed blade surface that is designed in such a way that it meets the necessary flow-technical conditions with regard to shape and surface design.

[0012] Compared to a foldable membrane, the blade consisting of individual lamellae has the advantage that its components can assume a defined shape and arrangement in both the compressed and expanded states. The individual lamellae can each be pivotally attached to the rotor shaft, advantageously pivoting in a plane containing the longitudinal axis of the rotor shaft or an axis parallel to such a shaft, whereby the attachment points can run helically around the rotor shaft to create a helical blade when unfolded. However, other attachment methods are also conceivable, in which the lamellae are attached, for example, to one or more webs or cross members, which in turn are connected to the rotor shaft.

[0013] The individual lamellae can be of equal length or of different lengths, depending on the final shape of the blade. The pivoting ability of the individual lamellae is limited so that, when unfolded, they can withstand the flow counterpressure of the fluid being transported. However, the lamellae can also support each other by adjoining one another and, if necessary, interlocking. For example, the lamellae can be designed like the elements of a bird's feather, with the keel of the feather corresponding to the rotor shaft.

[0014] The blade design can be such that the blade expands due to fluid counterpressure when rotating in the operating direction, and compresses due to the action of the medium in which the blade moves when rotating in the opposite direction. This makes the compression and expansion movement particularly easy, without the need to overcome significant forces. This allows such a pump to be removed easily and without risk of damaging body vessels in medical applications.

[0015] A particular embodiment of the invention provides that at least two slats, in particular each of the slats, is dimensionally stable, in particular rigid.

[0016] The blade's flexibility is not achieved through the flexibility of a membrane, but rather through the mobility of the individual lamellae relative to one another. To achieve this, the lamellae must not exceed a certain width. For example, the blade can advantageously consist of at least 10 or at least 50 lamellae. Such a blade can have a very small overall size, preferably less than 5 mm, for example, a diameter of 2 mm when compressed.

[0017] A further advantageous embodiment of the invention can provide that adjacent lamellae are in sealing contact with one another along a longitudinal side which extends at least partially radially with respect to the rotor axis.

[0018] While it's conceivable for the fins to leave gaps between them, the efficiency of the fluid pump increases with the tightness of the blade formed by the fins. It's therefore advantageous if the fins abut each other along their long sides and, if possible, leave no gaps between them.

[0019] It can also be provided that directly adjacent lamellae are positioned against each other in such a way that they cannot pivot relative to each other around the rotor axis in at least one direction. This allows the individual lamellae to support each other and, during operation, withstand the counterpressure of the fluid being pumped. Support in the azimuthal direction is provided, particularly when the lamellae are distributed helically around the circumference of the rotor shaft.

[0020] The invention can also be designed such that adjacent slats overlap each other in the region of the long side. Overlapping the slats creates a particularly high level of tightness, and in addition, the slats can mutually support each other in the overlapping area.

[0021] Particularly high stability and tightness between the slats is achieved by interlocking adjacent slats along their long sides. Any type of form-fitting design of adjacent slats can be provided, for example, by providing a fold along the long sides of the slats, for example, in the form of a thin sealing lip.

[0022] To create a positive and tight connection, it can also be provided that at least one slat, in particular all slats, have a convex cross-section on one of its long sides and a concave cross-section on the other. The corresponding convex or concave structure can be round, elliptical, or designed as a groove or notch.

[0023] Advantageously, adjacent lamellae can be connected to each other by a flexible element, in particular a band or membrane. The blade's foldability then results in a fan-like configuration, in which wide, rigid support rods are connected to each other by narrow membranes or bands.

[0024] To stabilize the individual slats, they can each have a stiffening structure in their cross-section, for example, a longitudinal web. However, it can also be provided that the individual slats are hollow with a round or square cross-section.

[0025] The invention can advantageously be implemented by an airfoil in which at least two lamellae are connected to one another by a hook-and-loop connection. Such a hook-and-loop connection consists of small hook-like elements on one side and loop-like elements on the other side, which can advantageously be microscopically small.

[0026] The invention can be further advantageously designed in that the connection can be released by applying a load to the blade in the axial direction of the rotor and / or by relative movement of two adjacent lamellae along their respective longitudinal sides and in the longitudinal direction of the lamellae.

[0027] The longitudinal direction of the lamellae is determined by the direction in which the respective lamella extends away from the rotor shaft.

[0028] Due to the described structure of a blade for the rotor of a fluid pump, the blade can be designed to be particularly stable and compressible in a defined manner, which in particular allows good compressibility and a small final diameter of the rotor in the compressed form to be achieved.

[0029] A further development provides that a compressible and expandable blade is provided for the rotor of a fluid pump, in particular a catheter pump, wherein at least two lamellae, which are arranged next to one another, are each pivotable relative to a rotational axis of the rotor and movable relative to one another and, in the expanded state, abut one another in such a way that together they form a continuous blade surface, wherein the at least two lamellae arranged next to one another belong to different rotor segments, wherein a rotor segment contains at least one lamella and a hub segment.

[0030] This makes it possible to build a rotor "sequentially," with individual rotor segments layered axially. These rotor segments do not need to be welded together (although they could possibly be); it is sufficient that they are securely fixed to one another.

[0031] Because the rotor segments each have at least one lamella and a hub segment, the hub segment can provide the connection to the rotor shaft, or the hub segment can also represent an axial section of the rotor shaft itself. By combining different hub segments, the pitch of the helix can be influenced. This enables the cost-effective construction of a helix with an uneven pitch, with the pitch advantageously increasing in the conveying direction.

[0032] The rotor segments can be made of various materials, such as shape-memory materials, particularly shape-memory metals or shape-memory plastics. In addition to Nitinol, polymers with the desired properties are suitable.

[0033] A further development provides for the slats to be individually coated and / or covered with a membrane, with the coating / membrane between two adjacent slats being connected at most by force and / or form. This preserves the advantage of the “bird’s feather” principle, whereby folding individual slats requires little force (particularly when inserting them into a lock), but on the other hand it can generate a high fluid counter pressure (due to the mutual supporting effect). Because the individual slats (or certain groups of slats combined) are each individually coated or covered with a membrane, the coating / membrane creates an even better sealing effect in the boundary area between several slats / groups of slats, and also improves flow and / orBiocompatible adaptation of the blade to the medium to be pumped (e.g., blood) becomes possible. This can also result in weight and stability advantages, as the blades themselves, for example, require a metal frame, which is then coated or overmolded with a plastic membrane or a polymer matrix. This is a significant improvement over blade arrangements in which the entire blade is overmolded with a single membrane or a single overmold, since such arrangements require higher forces during compression due to the limited deformability of the blade group(s).

[0034] A particularly advantageous development provides that the at least one lamella and the hub segment of the rotor segment are one-piece. This means that they can be manufactured integrally or from a single body, preferably a tube or a flat material (raw material). The thickness of the raw material is preferably 5 µm to 500 µm, particularly preferably 20 µm to 200 µm.

[0035] A further development provides for at least two adjacent rotor segments to be connected to one another in a form-fitting, torsion-proof manner. This can be ensured by appropriate engagement elements (elevations / recesses). This also significantly simplifies assembly. A further development provides for a single rotor segment to have a single hub element and one, two (or possibly more) laminations. For example, the rotor segment can have a single lamination, but a "vane arrangement" is also conceivable, in which two laminations (preferably opposite each other) protrude. Various arrangements are possible here, primarily depending on the amount of lamination area required.If a particularly large lamella area is required, a flat material or a tube material with a large diameter can be selected, for example, whereby a diameter change (not understood) can then later take place in the area of ​​the hub segment to adapt to the rotor shaft.

[0036] A method for producing a rotor segment or a blade with multiple rotor segments provides for structures for hub segments and lamellae to be cut out of a (for example, tubular or flat) base body (for example by laser, wire erosion, or etching), leaving a connecting web between the hub segment and lamellae to ensure the advantages of a one-piece design. The lamellae can then be plastically deformed in their radially projecting normal state using appropriate forming tools, whereby they correspond to the expanded (but still subjected to fluid pressure) state of the subsequent blade. If necessary, a chemical etching treatment or further laser treatment of the lamella can then be carried out, for example to ensure smoother or different surfaces in order to influence the flow properties of the lamella.For example, the profile of the slat can also be adjusted to improve airflow.

[0037] The rotor segments can then be joined axially to form a rotor shaft. These rotor segments are preferably joined together using material-to-material bonding methods, such as gluing or welding, even if a positive fit is previously provided by complementary indentations / elevations.

[0038] Another development provides that rotor segments with connecting webs arranged between the rotor segments can be machined out of a flat material and arranged on a rotor shaft by folding them out of the surface plane of the flat material in such a way that a helical shape of the blade automatically results.

[0039] A further development provides for several slats to be part of a slat body, whereby they are only connected to each other at their base. This, in turn, allows the slats to be easily folded, since they are not connected in their end region, which protrudes radially from the rotor (in the expanded state), and thus the slats can be easily deformed individually.

[0040] The lamella body can be inserted into a hub body in such a way that, when the outer tips of the lamellae are unloaded, a helical shape of the blade is formed. For example, the hub body is designed as a sleeve with spiral longitudinal slots into which the lamella body is inserted, so that later, in a finished catheter pump / fluid pump, the hub body represents the outer circumference of the rotor shaft.

[0041] A further development provides for the lamella body to have weakenings in the base area of ​​the lamellae to achieve higher tangential deflections of the lamellae with the same force applied (compared to the state in which no weakenings are present). This not only achieves good stiffness of the lamella with respect to the fluid, but also ensures sufficient flexibility during the initial deformation of the lamella body into the helical shape.

[0042] All of the above-mentioned lamella arrangements make it possible to produce catheter pumps for insertion into human vessels, in particular for intraventricular use, wherein a rotor with an impeller blade is arranged in the distal end region of the catheter pump and the pump has a conveying direction for conveying body fluid from distal to proximal and the impeller blade has a flow pressure side and a flow suction side.

[0043] A further development provides that, on the flow pressure side, the proximal region of a distal lamella overlaps the distal region of an adjacent proximal lamella. This determines the type of "step" of the lamellae. The advantage is that this type of step is very gentle on the blood and is blood-compatible. The erythrocytes do not collide with the step in the pumping / flow direction; instead, they "fall down the step."

[0044] According to one embodiment, it is possible to close, coat and / or extrusion-mold the individual lamellae in such a way that (at least in some areas) a constant / continuous curvature of the blade (the rotor blade, the blade) is provided on the flow pressure side and / or flow vacuum side.

[0045] A further development provides that the slats are applied in a compressed state essentially by deflecting the slats. This is achieved (for example, in an embodiment according to Fig. 13) in such a way that a sheath and / or sheath is arranged proximal to the rotor and the rotor is inserted into the sheath and / or sheath in a proximal direction, the laminations being bent or folded substantially one after the other (first the most proximal, then the one closest distal to the most proximal, etc.) (i.e. the blades or rotor blades are not bent or folded all at once, but instead the laminations are bent or folded substantially one after the other. This has the advantage that lower force requirements are required). The sheath or sheath can have a tubular cross-section. It is also possible to provide a compressible rotor housing, etc. between the sheath or sheath and the rotor, without departing from the principle of bending / folding the individual laminations one after the other described above. Note: In the context of this patent application, “bending or folding” meansBending the laminations substantially one at a time" means that, in particular, the beginning (the first phase) of bending or refolding the laminations occurs in such a way that one lamination is bent at a time. In the case of rotors with multiple rotor blades, several laminations having the same axial position may be bent or refolded simultaneously.

[0046] It should be noted again that the coating of individual slats or groups of slats described above can be carried out with a membrane (plastic or metal foil) or any other coating.

[0047] The invention is shown below using an exemplary embodiment in a drawing and then described.

[0048] It shows: Fig. 1 schematically shows a rotor shaft and a blade in a three-dimensional view, Fig. 2 schematically shows part of a blade with several lamellas, Fig. 3 a rotor shaft in cross-section with a lamella in two positions, Fig. 4 a rotor shaft in cross-section with two lamellas in two positions each, Fig. 5 a view of a rotor shaft with four lamellas, Fig. 6 a view of a rotor shaft with two configurations of lamellas, Fig. 7 a view of a rotor shaft with two configurations of lamellas and Fig. 8 a schematic representation of a cardiac catheter pump with a rotor and blades in a heart chamber, Fig. 9 to 12 schematic 3-dimensional representations of overlapping lamellae, Fig. 13a to 131 an embodiment of the blades according to the invention, wherein these blades consist of lamellae of adjacent rotor segments, Fig. 14a to 14d embodiments of a blade in which a lamella body is inserted into a spiral-shaped notch of a sleeve body, and Fig. 15a and Fig. 15b shows a further embodiment of a blade constructed from rotor segments.

[0049] Fig. Figure 1 shows a rotor shaft 1 with a blade 2 composed of individual, schematically indicated lamellae 3, 4, 5. The individual lamellae are each pivotally mounted on the rotor shaft 1 by their base points 3a, 4a, 5a, with the base points of the lamellae encircling the rotor shaft 1 in a helical configuration.

[0050] In this way, a helical structure of a blade is created which, when rotating around the rotor shaft 1, causes an axial transport of a liquid in the direction of arrow 6.

[0051] The special design of the blade according to the invention is described in more detail in the Fig. 2. There, the lamellae 3, 4, 5 are shown in a first position in the expanded form of the blade, with the adjacent lamellae lying closely against one another with their longitudinal sides, thus forming a smooth and dense surface for the flowing fluid.

[0052] In the position shown in dashed lines and designated 7, the individual lamellae are folded slightly toward the rotor shaft 1. It is important for the deformability of the blade as a whole that the individual lamellae 3, 4, and 5 are movable relative to one another, particularly in the longitudinal direction. This eliminates the need to fold the corresponding surface; instead, the individual lamellae can be folded close to the rotor shaft, as shown in the further position 8 of the lamellae.

[0053] This allows the impeller to be compressed to a large extent, ie reduced in terms of radius relative to the rotor shaft 1 or its longitudinal axis 1a.

[0054] No significant elastic counterforces are generated, so that the rotor can be compressed practically force-free, for example when this is necessary to insert or remove a corresponding fluid pump from a body vessel.

[0055] Is in the Fig. 2 indicates a pivotability of the individual lamellae in the longitudinal direction of the rotor shaft 1 in the plane of the rotor shaft axis, but the invention is not limited to this. Fig. 3 shows a pivotability of a slat 3 in the azimuthal direction, as indicated by the arrow 9.

[0056] Fig. Figure 4 shows a further variant of such a design, wherein webs 10, 11 are provided on the rotor shaft 1 and the lamellae 3, 4 are pivotally mounted on the webs 10, 11 helically encircling the rotor shaft 1. The pivoted positions are shown in the Fig. 4 are shown in dashed lines.

[0057] It is clear that pivoting the vanes in the position shown by the dashed lines results in a compression of the rotor. For example, compression of the rotor can be caused by rotating the rotor in a direction opposite to the operating direction. Accordingly, the rotor is clamped by rotating it in the operating direction.

[0058] In principle, the individual lamellae can also be attached to the cross members of the rotor shaft 1 and, when clamped, run parallel to the longitudinal axis of the rotor shaft. It is important that they can be folded individually to reduce the rotor diameter.

[0059] In the Fig. Figure 5 shows a schematic plan view of four fins 12, 13, 14, and 15, each of which has a rectangular and hollow cross-section to create greater longitudinal rigidity for the individual fins. This is advantageous because, despite the rigidity of the individual fins, the entire blade can be easily folded.

[0060] The Fig. Figure 6 shows two blade configurations. On the left side, blades 16, 17 are shown, each with an overlap lip 18, 19. Adjacent blades are sealed on the one hand and supported on the other hand by the overlap lip 18, 19 of the adjacent blade. This stiffens the entire blade, allowing the blade to withstand increased fluid backpressure during operation.

[0061] On the right side of the Fig. 6 shows three lamellae 20, 21, 22, each of the lamellae having a web 20a, 21a, 22a running in the radial direction of the rotor shaft 1.

[0062] Fig. 7 shows on the left side of the plan view of the rotor shaft 1 three lamellae 23, 24, 25, each of which has a convex protrusion on one side 26 and a concave indentation on the other side 27 on its longitudinal side surface, so that adjacent lamellae can interlock and thus support each other against an azimuthal pivoting movement.

[0063] On the right side of the Fig. 7 shows slats 28, 29, each of which has a concave and a convex bulge with a round cross-section on its longitudinal sides. This design has the advantage that adjacent slats can rotate relative to each other about their longitudinal axes to a limited extent.

[0064] In principle, the individual slats can either be attached to the rotor shaft 1 by means of a pivot joint or be designed to be flexible or pliable in their base area so that they can pivot relative to the rotor shaft as a whole. The individual slats can also be glued to a flexible band at their base ends or attached to it in some other way, whereby the band can be attached to the rotor as a whole with the slats. The flexibility of the band can then ensure the pivotability of the individual slats.

[0065] In the Fig. Figure 8 schematically illustrates the use of a fluid pump with an impeller blade according to the invention. The pump 30 is positioned in a heart chamber 31 and, as indicated by arrows 32, sucks blood, which is conveyed into a vessel 33, as shown by arrows 34. The pump 30 is attached to a catheter 35, through which a shaft 1 extends centrally. This shaft is shown only in the area of ​​the pump 30 and is driven in rotation by a motor 36. The shaft moves a rotor 37, which has an impeller blade shown only schematically.

[0066] In its expanded state, the pump 30 has a diameter that, in extreme cases, may even be larger than the inner diameter of the vessel 33. For this purpose, the impeller is fully expanded. However, it can also be compressed to insert or remove the pump 30. As shown above, the individual vanes can be folded onto the rotor shaft 1, and the housing of the pump 30 collapses accordingly. For this purpose, this housing can consist, for example, of a membrane that is tensioned by a frame or by the fluid pressure generated in the pump 30.

[0067] Fig. 9 shows three flat slats overlapping on their long sides, which may, for example, have a Velcro connection in their overlapping area.

[0068] Fig. 10 shows slats which have edges angled at 90 degrees along their long sides, with which they hook into each other, while in Fig. 11 shows a variant with an angle of less than 90 degrees, which also allows the slats to be fixed relative to each other.

[0069] Fig. Finally, 12 represents a variant with a curved edge, which serves the same purpose of mutual fixation.

[0070] Fig. Figure 13a shows a rotor segment 40, which consists of a hub segment 46 and a lamella 43 connected to it in one piece. The rotor segment is made of a tubular material, whereby the hub segment 46 essentially still has the tube diameter (it is also a partially closed ring) and the lamella is bent out. For this purpose, the lamella was first cut out in its original shape using a laser beam and then plastic deformation was achieved on a molded body, in which the Fig. 13a. Subsequently, the lamellae were subjected to etching and / or surface treatment. To produce a final blade (see Fig. 13c) several rotor segments are then arranged axially to each other.

[0071] A single slat can also be covered with a plastic or metal foil / membrane or even overmolded to achieve a larger surface area.

[0072] Fig. Figure 13b shows another view of the rotor segment 40, where stress relief slots 54 are shown in the base area of ​​the lamella 43. It can be seen that the Fig. The rotor segment shown in Figures 13a / 13b has a closed ring shape in the lower area of ​​the hub segment. It can also be seen that the rotor segment connects the hub segment and the lamella in one piece.

[0073] Fig. Figure 13d shows another embodiment of a rotor segment cut from tubular material and not yet fully finished, in which the fins 43, 43a are not yet unfolded. Here, too, stress relief slots 54 are already visible, and in particular, positive-locking elements 47 in the form of protrusions can be seen, which can engage in corresponding recesses of axially adjacent rotor segments, thus fixing the position of the fins (which will later be unfolded radially).

[0074] A rotor with a blade 42 according to the invention is shown in Fig. 13d is shown in more detail. The preferred conveying direction of the rotor is indicated by the right-hand arrow, which indicates that the flow pressure side 51 and the (opposite side of the lamellae) is the flow suction side 52. Several rotor segments 40 are arranged axially next to one another with their respective hub segments 46. This also results in a staggered arrangement of adjacent lamellae 43, 44, 45, which are arranged on a rotor shaft 41. This Fig. The rotor shown in Figure 13d may be part of a Fig. 8, in particular an intraventricular catheter pump. This is a catheter pump for insertion into human vessels, wherein the rotor with a blade is arranged in the distal end region of the catheter pump, and the pump has a conveying direction for conveying body fluid from distal to proximal, and the blade has a flow pressure side 51 (see above) and a flow suction side 52.

[0075] It is in Fig. 13d clearly shows that on the flow pressure side 51, the proximal region of the distal lamella 44 covers the distal region of the proximal lamella 43. This results in the formation of a closed blade, at least in the radially outer region of the lamellae. The lamellae are designed in a "hockey stick" shape. This results in very good overlap in the flow-relevant area, as well as good foldability. Finally, even at high fluid backpressure, only a minimal flow loss occurs due to the aforementioned orientation of the lamella staggering.

[0076] In addition, Fig. Figure 13d shows that the lamellae 43, 44, 45 are compressed essentially by deflecting the lamellae in the direction of the flow pressure (see arrow 53). This arrow is shown once in the distal and once in the proximal region of the rotor. The "hockey stick" design of the lamellae also offers the advantage that the rotor can be retracted with little force and without snagging when retracted into a sheath located proximal to the rotor.

[0077] Fig. Figure 13e shows a further embodiment of a rotor according to the invention, in which two blades 42 and 42a are provided. Fig. The rotor shown in Figure 13e is a combination of several rotor segments according to Fig. 13c.

[0078] Fig. 13f shows a combination of three rotor segments 40, which form parts of a rotor shaft 41, in which three hub segments 46 are also arranged one behind the other, resulting in a common blade 42.

[0079] Fig. 13g shows a simple embodiment of a rotor segment 40 with two radially projecting lamellae. Fig. 13h shows further embodiments of rotors according to the invention. Fig. 13i and Fig. 13j show again that in Fig. 13c shows the rotor segment, where the stress relief slots 54 as well as the form-fitting ends 47 (elevation) and 48 (indentation) serving for the form-fitting are shown even better.

[0080] Fig. 13k shows a blade 42 on a rotor shaft 41, Fig. Figure 13l shows two photographs. In the left image, a blade 42 consisting of several lamellae is drawn into an insertion sheath 55. On the right, the rotor shaft 41 is visible. In the right-hand image, the blade 42 is completely retracted into the insertion sheath 55.

[0081] Fig. Figure 14a shows another embodiment of a rotor in which a hub body 50 has two spiral slots (see Fig. 14b), into which a lamellar body 49 (see Fig. 14c). The view of a flat material from which the slat body 49 is cut by laser is shown in Fig. 14d. For illustration purposes, the Fig. 14d and / or 15a also show a possible overmolding / encasing of a lamella (with cross-hatching). In another embodiment, the cross-hatching can be understood to mean that the entire cross-hatched area is made of flat material.

[0082] In the Fig. 15a and Fig. Figure 15b shows another embodiment of a blade. Here, a blade base body 49 is cut from a flat material, with connecting struts between individual rotor segments. By tilting individual rotor segments out of the surface plane and recombining them with each other, a helical structure is automatically created. This works, for example, in such a way that, according to Fig.15a, the rotor segment arranged on the left is rotated out of the plane and placed on the next element from the left (and so on for the other rotor elements) such that the openings of the hub segment are aligned. If these hub segments are then arranged on a common rotor shaft, a helical arrangement of the laminations 42, 43, 44 automatically results. The laminations can be rotated relative to their longitudinal axis in a subsequent forming process to achieve overlapping of the laminations.

Claims

[1] Compressible and expandable blade (2) for the rotor of a fluid pump, characterized by at least two lamellae (3, 4, 5, 12, 13, 14, 15, 16, 17, 20, 21, 22, 23, 24, 25, 28, 29) which are arranged next to one another and are each pivotable relative to a rotational axis (1a) of the rotor and movable relative to one another and, in the expanded state, bear against one another in such a way that together they form a continuous blade surface, wherein the at least two lamellae (43, 44, 45) arranged next to one another belong to different rotor segments (40), wherein a rotor segment (40) contains at least one lamella and a hub segment (46). [2] Blade according to claim 1, characterized by that at least two lamellae (3,4, 5,12,13,14,15,16,17,20,21,22,23,24,25,28,29) are dimensionally stable, in particular rigid. [3] Blade according to claim 1 or 2, characterized bythat adjacent lamellae (3,4,5,12,13,14,15,16,17,20,21,22,23,24, 25,28,29) lie sealingly against one another along a longitudinal side which extends at least partially radially with respect to the rotor axis (1a). [4] Blade according to claim 2 or 3, characterized by that directly adjacent lamellae (16, 17, 20, 21, 22, 23, 24, 25, 28, 29) lie against one another in such a way that they cannot be pivoted relative to one another about the rotor axis (1a) in at least one direction. [5] Blade according to claim 3 or 4, characterized by that adjacent slats (16,17) overlap each other in the area of ​​the long side. [6] Airfoil according to claim 3 or 4, characterized by that adjacent slats (23,24,25,28,29) interlock in the area of ​​the long side. [7] Airfoil according to claim 1 or one of the following, characterized bythat adjacent slats (3,4,5,12,13,14,15,16,17, 20,21,22,23,24,25,28,29) are connected to one another by a flexible element, in particular a band or a membrane. [8] Airfoil according to claim 1 or one of the following, characterized by that at least one of the slats (20,21,22) has a stiffening structure (20a,21a,22a) in cross-section. [9] Blade according to claim 8, characterized by that at least one lamella (20, 21, 22) has on its outer side at least one stiffening web (20a, 21a, 22a) extending in its longitudinal direction. [10] Blade according to claim 8, characterized by that at least one lamella (12,13, 14,15) is hollow in cross-section. [11] Airfoil according to claim 8, 9 or 10, characterized by that at least one lamella (28,29) has a convex shape in cross-section on one of its longitudinal sides and a concave shape on the other longitudinal side. [12] Airfoil according to claim 1 or one of the following, characterized by that at least two slats (3,4,5,12,13,14,15,16,17, 20,21,22,23,24,25,28,29) are connected to each other by a Velcro-like connection. [13] Blade according to claim 12, characterized by that the connection can be released by applying a load to the blade in the axial direction of the rotor. [14] Airfoil according to claim 12, characterized by that the connection can be released by relative movement of two adjacent slats (3,4,5,12,13, 14,15,16,17,20,21,22,23,24,25,28,29) along their respective longitudinal sides and in the longitudinal direction of the slats. [15] Blade according to one of claims 1 to 14, characterized by that the at least one lamella (43, 44, 45) and the hub segment (46) of the rotor segment (40) are one-piece. [16] Airfoil according to one of claims 1 to 15, characterized bythat two adjacent rotor segments (40) are connected to each other in a form-fitting manner and are secured against rotation. [17] Blade according to one of claims 1 to 16, characterized by that each rotor segment has one, two or more lamellae (43, 44, 45). [18] Airfoil according to one of claims 1 to 17, characterized by that several slats (43, 44, 45) are part of a slat body (49), which are only connected to one another in their base region. [19] Airfoil according to claim 18, characterized by that the lamella base body (49) can be inserted into a hub body (50) in such a way that in the unloaded state of the radially outer tips of the lamellae a helical shape of the blade is formed. [20] Airfoil according to one of the preceding claims, characterized bythat the slats (3, 4, 5; 43, 44, 45) are each individually coated and / or covered with a membrane, wherein a connection of the coating / membrane of two adjacent slats is at most force-fitting and / or form-fitting. [21] Airfoil according to one of the preceding claims, characterized by that on the flow pressure side (51) the proximal region of the distal lamella covers the distal region of the proximal lamella. [22] Airfoil according to one of the preceding claims, characterized by that the application of the lamellae (43, 44, 45) in a compressed state is possible essentially in a sequence, starting with the most proximal lamella. [23] A method for producing an airfoil according to any one of claims 1 to 22, characterized byin that structures for hub segments (46) and lamellae (43, 44, 45) are cut out of a preferably tubular base body, preferably by means of a laser or by wire erosion, a connecting web remaining between the hub segment (46) and lamellae (43, 44, 45), then at least the lamellae are plastically deformed in a radially projecting state and / or by heat treatment, furthermore, if necessary, a surface treatment of the lamellae is then carried out, then the rotor segments (40) are axially joined to form a rotor shaft (41) and, if necessary, the rotor segments (40) are fixed, preferably by welding, particularly preferably by laser welding. [24] Method according to claim 23, characterized bythat rotor segments with connecting webs arranged between the hub segments can be machined from a flat material and arranged on a rotor shaft by folding them out of the surface plane of the flat material in such a way that a helical shape of the blade is obtained. [25] Catheter pump for insertion into human vessels, in particular for intraventricular use, wherein a rotor with a blade (2; 42) can be arranged in a vessel of a mammal (vessel of a mammal or human vessel), characterized by that the pump has a conveying direction for conveying body fluid and the blade has a flow pressure side (51) and a flow suction side (52) and contains a blade according to one of claims 1 to 22.

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