Blood pump

Abstract

The present invention relates to a blood pump 10, in particular an intravascular blood pump, comprising a pump housing 12 having a blood inlet 14 and a blood outlet 16 connected by a passage 18, an impeller 20 disposed within said pump housing 12, a drive unit 26 configured to drive the impeller 20, and a bearing arrangement 40, 42 for rotatably supporting the impeller 20, the bearing arrangement 40, 42 comprising at least one pivot bearing 40.

Description

[Technical field]

[0001] The present invention relates to a blood pump. In particular, the present invention relates to an intravascular blood pump for percutaneous insertion into a patient's blood vessel to support blood flow in the patient's blood vessel. The blood pump may also be an intracardiac blood pump or any other type of ventricular assist device. [Background technology]

[0002] Various blood vessel pumps are known in the prior art, such as, for example, axial blood pumps, centrifugal (i.e. radial flow) blood pumps, or mixed blood pumps, in which blood flow is generated by axial and radial forces. Such blood vessel pumps can be introduced into the patient's heart to support blood flow from the heart into an artery, for example the aorta. The blood pump can be introduced percutaneously during cardiac surgery via the vascular system, such as by catheterization. After the blood pump is placed, blood is pumped by the blood pump from the left ventricle into the aorta to restore an adequate systemic blood flow. Thus, a blood pump typically comprises a pump housing having a blood flow inlet and a blood flow outlet connected by a passage, a pump element in the form of an impeller arranged in said pump housing, and a drive unit configured to drive the impeller. A corresponding blood pump is known, for example, from WO 2021 / 043776 A1.

[0003] The blood pump disclosed in WO 2021 / 043776 A1 comprises a drive unit configured to contactlessly drive the impeller. The impeller is thus magnetically coupled to the stator in that it comprises magnets arranged adjacent to electrically magnetized regions in the stator. Rotation can be transmitted to the impeller based on the attractive forces between the magnets of the impeller and the magnetized regions in the stator. In particular, a rotating magnetic field is provided in the stator that rotates the impeller in that the control unit applies appropriate voltages to the stator in a controlled manner.

[0004] To minimize friction losses during rotation of the impeller and allow safe radial travel, the impeller is supported via bearings at spaced points. Furthermore, the bearings must be constructed to tolerate some deviation from concentricity caused by, for example, clotting or settling of blood particles. The bearings used are therefore constructed to greatly minimize adhesion of blood particles, further taking into account the intended life of the bearings.

[0005] In this regard, it should be further considered that the blood pump may be placed inside the patient's body for weeks or months, while the impeller rotates continuously, typically at peaks of over 10,000 rpm and up to 30,000 rpm. The bearings are therefore exposed to high loads, and blood particles may further impair the correct functioning of the bearings. It is therefore an object of the present invention to provide an improved bearing arrangement. Summary of the Invention [Means for solving the problem]

[0006] The blood pump according to the invention may correspond to the blood pumps described above. The blood pump may therefore be an intravascular or intracardiac blood pump. According to a first aspect, the blood pump comprises a pump housing having a blood inlet and a blood outlet connected by a passage, a pump element, in particular an impeller, and a drive unit configured to drive the impeller. The impeller is arranged in the pump housing. The blood pump further comprises a bearing arrangement for rotatably supporting the impeller. The bearing arrangement comprises at least one pivot bearing. The pivot bearing allows a certain deviation from concentricity during rotation of the impeller relative to the pump housing.

[0007] Preferably, the pivot bearing comprises a first pivot bearing member and a second pivot bearing member. The first pivot bearing member is pivotable relative to the second pivot bearing member, the first pivot bearing member comprising a first abutment portion and the second pivot bearing member comprising a second abutment portion. The first abutment portion of the first pivot bearing member at least partially contacts the second abutment portion of the second pivot bearing member. The first abutment portion of the first pivot bearing member may be a first contact portion. The second abutment portion of the second pivot bearing member may be a second contact portion. The contact between the first abutment portion of the first pivot bearing member and the second abutment portion of the second pivot bearing member is preferably a point contact. The point contact reduces overall wear and mechanical stress during rotation of the impeller. In this context, it should be mentioned that the terms "at least partially" or "partially" as used herein have both the meaning of partial and the meaning of whole or complete, respectively.

[0008] Preferably, the first abutment portion of the first pivot bearing member comprises a spherical portion. The second abutment portion of the second pivot bearing member may comprise a first spherical cap, the spherical portion being able to abut or contact the first spherical cap. The first spherical cap may be a first calotte. The spherical portion may comprise a convex surface and the first spherical cap may comprise a concave surface. The pivot bearing comprising the spherical portion and the first spherical cap runs smoothly during rotation of the impeller and is furthermore self-centering since its center of gravity is on the axis of rotation of the impeller.

[0009] Preferably, the spherical portion has a first radius and the first spherical cap has a second radius. The second radius may be greater than the first radius. This further improves the self-centering ability of the pivot bearing. Furthermore, a point contact between the spherical portion and the first spherical cap is established.

[0010] Preferably, the first pivot bearing member comprises a support element and a ball, the ball being able to abut against the support element. The ball comprises a spherical portion. The ball may be separate from the support element or may be integrally formed with the support element. Thus, the first pivot bearing member is easy to manufacture.

[0011] Preferably, the support element comprises a second spherical cap having a third radius. The ball may be in abutment against the second spherical cap, and the third radius may be greater than the first radius. The second spherical cap may be a second carrot. The second spherical cap may comprise a concave surface. If the ball is free to rotate relative to the second spherical cap, an increased pivoting movement may occur between the first pivot bearing member and the second pivot bearing member.

[0012] The ball can be fixed to the support element. The ball can be fixed by adhesive or by a suitable connecting element, for example a mounting pin. The first pivot bearing member is therefore easy to manufacture. This further facilitates the assembly of the pivot bearing and thus the blood pump.

[0013] Preferably, the first abutment of the first pivot bearing member comprises at least one notch, preferably a plurality of first notches. The plurality of first notches may be evenly distributed along the circumference of the first abutment. Preferably, the second abutment of the second pivot bearing member comprises at least one second notch, preferably a plurality of second notches. The plurality of second notches may be evenly distributed along the circumference of the second abutment. During rotation of the impeller, blood flow is established between the blood flow inlet and the blood flow outlet. A portion of the blood flow is directed through the pivot bearing, the notches acting as a fluid bypass for improving rinsing and cooling of the pivot bearing.

[0014] Preferably, the axial extension of the at least one second cutout is non-parallel to the main axis of the second pivot bearing member, or the axial extension of the at least one second cutout is parallel to the main axis of the second pivot bearing member. If necessary, the at least one second cutout can be inclined with respect to the main axis of the second pivot bearing member in order to optimally rinse and cool the pivot bearing. Generally, the main axis of the second pivot bearing member coincides with the axis of rotation of the impeller.

[0015] In one embodiment, the first pivot bearing member comprises a slot extending from the first abutment portion. Preferably, the slot divides the first abutment portion of the first pivot bearing member into two portions. In this embodiment, the first abutment portion of the first pivot bearing member preferably comprises a first spherical cap and the second abutment portion of the second pivot bearing member preferably comprises a first spherical portion.

[0016] In particular, the slot may be configured such that a rotation of the first pivot bearing member results in a pumping action from one side of the slot to the other side of the slot. The slot is preferably delimited by two parallel side surfaces. Preferably, the two side surfaces are parallel to each other and / or to the mid-plane of the support element. In particular, the slot does not extend over the entire length of the slot and over the entire diameter of the support element. In a first section of the slot facing the first abutment, the slot may extend over the entire diameter of the support element. Thus, in the first section of the slot, the slot preferably extends over both sides of the support element. In a second section of the slot, the slot extends only to one side of the support element. In particular, the slot width of the slot gradually narrows in a direction away from the first abutment.

[0017] Preferably, the impeller comprises a bearing receptacle therein. At least one opening can connect the passage with the bearing receptacle, and the pivot bearing is at least partially arranged in the bearing support. Thus, a part of the blood flow established during rotation of the impeller can be guided through the opening to the bearing receptacle and rinse and cool the pivot bearing accommodated in the bearing receptacle.

[0018] Preferably, the opening has a central axis pointing towards the second abutment of the second pivot bearing member. Thus, when the first abutment is in contact with the second abutment, the central axis also points towards the first abutment of the first pivot bearing member. Thus, a part of the blood flow entering the bearing receptacle through the opening is directed towards the first and second abutments which rotate relative to each other during the rotation of the impeller. Thus, the blood flow entering the bearing receptacle cools and rinses vital parts of the bearing member, where blood may coagulate, where blood particles may precipitate and where heat is generated.

[0019] Preferably, the impeller comprises a body and at least one primary blade helically protruding from an outer circumferential surface of the body, and the opening comprises an inlet provided on the outer circumferential surface of the body. At least a portion of the at least one primary blade may be arranged circumferentially of the body and tangential to the inlet. In other words, the inlet is arranged circumferentially within an axial extension of the at least one primary blade. This ensures that a sufficient portion of blood transported by rotation of the impeller passes through the inlet and enters the bearing receptacle.

[0020] The first pivot bearing member can be attached to the impeller and the second pivot bearing member can be attached to the pump housing. The pivot bearing members can be attached by adhesive. Additionally or alternatively, the pivot bearing members can be attached by press fit.

[0021] In one embodiment, the bearing arrangement further comprises at least one radial bearing, the pivot bearing rotatably supporting the impeller relative to the housing at one point of the impeller and the radial bearing rotatably supporting the impeller relative to the housing at another point of the impeller. The drive unit may be a non-contact electromagnetic drive unit configured to rotatably drive the impeller relative to the housing. The drive unit may establish an attractive force on the impeller. Thus, the impeller may comprise a magnet that interacts with the drive unit in that a rotating magnetic field is established within the drive unit for driving the impeller. The attractive force acts on the impeller in a direction away from the blood flow inlet such that no axial force acts on the radial bearing during normal operating conditions. Thus, the load acting on the radial bearing is reduced.

[0022] Preferably, the radial bearing comprises a first radial bearing member and a second radial bearing member, the first radial bearing member being mounted on the impeller and the second radial bearing member being mounted on the pump housing. The first radial bearing member may comprise a collar. The collar may extend at least partially circumferentially from an outer peripheral surface of the first radial bearing member. The collar may be provided adjacent to the second radial bearing member, and a gap may be formed axially between the collar and the second radial bearing member. Thus, the collar does not contact the second radial bearing member during normal operating conditions. However, in the event that the impeller moves axially (e.g. due to a fault), the collar activates an emergency abutment collar that limits axial movement of the impeller relative to the pump housing. Thus, possible damage to the impeller or the pump housing is prevented.

[0023] The radial bearing members may be attached by adhesive. Additionally or alternatively, the radial bearing members may be attached by press fit.

[0024] The foregoing summary and the following detailed description of the preferred embodiments will be better understood when read in conjunction with the appended drawings. For purposes of illustrating the present disclosure, reference is made to the drawings. However, the scope of the present disclosure is not limited to the specific embodiments disclosed in the drawings. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1 is a schematic perspective view of a blood pump. [Diagram 2] FIG. 2 is another schematic perspective view of the blood pump of FIG. 1. [Diagram 3] FIG. 2 is a detailed schematic diagram of the catheter attachment portion of the blood pump of FIG. 1. [Figure 4] FIG. 2 is a schematic side view of the blood pump of FIG. 1. [Diagram 5] FIG. 2 is a partial schematic cross-sectional view of the blood pump of FIG. 1. [Figure 6] FIG. 2 is a schematic side view of the impeller of the blood pump of FIG. 1. [Figure 7] FIG. 7 is a schematic rear view of the impeller of FIG. 6. [Figure 8] FIG. 13 is a schematic rear view of an alternative embodiment of an impeller. [Figure 9] 2 is a schematic cross-sectional view of a drive unit casing and a drive unit of the blood pump of FIG. 1. [Figure 10] FIG. 2 is a schematic exploded view of a stator and insulation assembly of the blood pump of FIG. 1. [Figure 11] 10 is a schematic cross-sectional view of an alternative embodiment of the impeller support of the drive unit casing of FIG. 9. [Figure 12] FIG. 2 is a schematic detailed view of a pivot bearing. [Figure 13] FIG. 13 is a schematic detail view of an alternative embodiment of the pivot bearing. [Figure 14] FIG. 13 is a schematic detail view of a further alternative embodiment of the pivot bearing; [Figure 15] FIG. 13 is a schematic detail view of a further alternative embodiment of the pivot bearing; [Figure 16] FIG. 4 is a schematic detailed view of the second pivot bearing member; [Figure 17] FIG. 11 is a schematic detail view of an alternative embodiment of the second pivot bearing member; [Figure 18] FIG. 11 is a schematic detail view of a further alternative embodiment of the second pivot bearing member; [Figure 19] FIG. 2 is a schematic detail view in cross section of a further alternative embodiment of a pivot bearing; [Figure 20] FIG. 20 is a diagram showing the impeller of FIG. 19 rotated 90°. [Figure 21] FIG. 20 is a schematic detail view of the first pivot bearing member and the second pivot bearing member of FIG. 19; [Figure 22] FIG. 2 is a schematic detailed view of a radial bearing. [Diagram 23] FIG. 2 is a further schematic detail of a radial bearing. [Figure 24] FIG. 4 is a schematic perspective view of a second radial bearing member of the radial bearing. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Blood pumps and pump housings Referring initially to Figures 1, 2 and 4, a schematic perspective view and a schematic side view of a blood pump 10 are shown. In this embodiment, the blood pump 10 is an intravascular pump, also known as a catheter pump. The blood pump 10 comprises a pump housing 12 having a blood inlet 14 and a blood outlet 16 connected by a passageway 18 (see, for example, Figure 5). Here, the blood outlet 16 is composed of a plurality of openings evenly distributed around the circumference of the pump housing 12. The pump housing 12 comprises a drive unit casing 22 and an impeller casing 24, and an impeller 20 disposed within the pump housing 12, i.e., within the impeller casing 24. The drive unit casing 22 and the impeller casing 24 are made of titanium or a titanium alloy, which provides high mechanical strength and thus allows the manufacture of the drive unit casing 22 and the impeller casing 24 with a small thickness. Furthermore, titanium is also highly biocompatible. The drive unit casing 22 and the impeller casing 24 are connected, for example, by adhesive. Both the blood flow inlet 14 and the blood flow outlet 16 are provided on the impeller casing 24. A drive unit 26 (see, for example, FIG. 9) is disposed within the drive unit casing 22. Features of the drive unit 26 are described in more detail below.

[0027] The impeller casing 24 includes a cannula mounting portion 28 at an axial end opposite the drive unit casing 22. The cannula mounting portion 28 is configured to receive a cannula (not shown) in a conventional manner. A catheter 30 is mounted to the catheter mounting portion 32 of the drive unit casing 22. As shown in the detailed view of FIG. 3 with the catheter 30 removed, the catheter mounting portion 32 includes a tubular portion 34 having a threaded structure 36 on its outer circumferential surface that substantially corresponds to a male thread. The threaded structure 36 is configured to threadably engage a helical member in the form of a Nitinol coil 38 of the catheter 30 of the blood pump 10. In particular, the Nitinol coil 38 of the catheter 30 is threaded onto the threaded structure 36 to mount the catheter 30 to the pump housing 12.

[0028] Impeller FIG. 5 shows a partial cross-section along the line AA shown in FIG. 4. Here, only the impeller casing 24 and the impeller 20 are shown in cross-section. The impeller 20 is arranged in the impeller casing 24 and is arranged to transport blood along the passage 18 in that it is rotatable about a rotation axis X (see FIG. 4) by means of a bearing arrangement 40, 42. The rotation axis X coincides with the central axis of the pump housing 12. Here, the bearing arrangement 40, 42 comprises a first bearing 40 in the form of a pivot bearing 40 and a second bearing 42 in the form of a radial bearing 42. The impeller 20 comprises a body 56 having a bearing receptacle 44 therein. The pivot bearing 40 is partially arranged in the bearing receptacle 44 as will be described in more detail below. The pivot bearing 40 allows a certain amount of pivoting movement of the impeller 20 relative to the pump housing 12.

[0029] The radial bearing 42 is supported by a crown 46 of the impeller casing 24. The crown 46 is located adjacent the blood inlet 14 and includes a central tubular portion 48 connected to the inner circumferential surface of the impeller casing 24 by a number of connecting arms 50. In this embodiment, a total of three connecting arms 50 are provided, which are evenly distributed around the circumference of the central tubular portion 48 of the crown 46. Of course, it is also contemplated that only two or more than three connecting arms 50 are provided.

[0030] The impeller 20 is provided at one axial end, i.e. the end facing towards the drive unit casing 22, with a number of magnets 52. Rotation of the impeller 20 is caused by a drive unit 26 which is magnetically coupled to the impeller 20, as will be explained in more detail below.

[0031] When the impeller 20 rotates about the rotation axis X, blood is conveyed from the blood flow inlet 14 through the passageway 18 to the blood flow outlet 16. Accordingly, at least one primary blade 54 helically protrudes from the outer circumferential surface of the body 56 of the impeller 20. In this embodiment, two primary blades 54 are provided. The primary blades 54 generate a primary blood flow along the passageway 18.

[0032] The impeller 20 further comprises at least one opening 58 connecting the passage 18 with the bearing receptacle 44. Here, two openings 58 are provided, each with an inlet 60 provided on the outer circumferential surface of the body 56 of the impeller 20. As shown in Figures 5 and 6, the inlet 60 is provided circumferentially within the axial extension of the primary blade 54. In other words, at least a portion of the primary blade 54 is provided circumferentially of the body 56 of the impeller 20 adjacent to the inlet 60. Each opening 58 has a central axis CA pointing towards the pivot bearing 40.

[0033] Furthermore, the impeller has a casing end 62 facing towards the drive unit casing 22 (see FIG. 7). A number of secondary blades 64 project from the casing end 62 towards the drive unit casing 22. The secondary blades 64 generate a secondary blood flow. The secondary blades 64 extend in a non-radial direction with respect to the rotation axis X of the impeller 20.

[0034] With respect to the embodiment shown in FIG. 7, each of the secondary blades 64 has a base point BP (BP) located on a base circle BC (BC) and an end point EP (EP) located on an end circle EC (EC) (in FIG. 7, the base point BP and the end point EP are shown for only one of the secondary blades 64). The base point BP is the radially innermost point of the secondary blade 64, and the end point EP is the radially outermost point of the secondary blade 64. The base circle BC and the end circle EC have a common center point CCP through which the rotation axis X extends. A straight line SL (SL) connecting the base point BP and the end point EP of each of the secondary blades 64 does not extend through the common center point CCP. Thus, each of the multiple secondary blades 64 is curved with respect to the straight line SL.

[0035] 8 shows an alternative embodiment with secondary main blades 64 and additional secondary auxiliary blades 65. The secondary auxiliary blades 65 are radially shorter than the secondary main blades 64 and are arranged circumferentially on the radially outer ends of the casing end 62 of the impeller 20.

[0036] Drive unit and drive unit casing 9 and 10, the drive unit 26 will be described in more detail. As mentioned above, the drive unit 26 is disposed within the drive unit casing 22 (see FIG. 9). The drive unit 26 includes a stator 66 and an insulation assembly 68. The drive unit 22 is configured to provide a rotating magnetic field that interacts with the magnets 52 of the impeller 20 to cause the impeller 20 to rotate about the axis of rotation X.

[0037] The stator 66 thus comprises a number of posts 70 and a number of coil windings 72 arranged around the posts 70. The posts 70 are arranged parallel to the axis of rotation X of the impeller 20. The coil windings 72 are in turn controlled by a control element (e.g. a printed circuit board 74) to generate a rotating magnetic field in a known manner. To strengthen the magnetic flux, the stator 66 further comprises a backplate 76 provided on a catheter end 78, i.e. on the side of the stator 66 that faces the catheter mounting portion 32 of the drive unit casing 22 in the assembled state.

[0038] The stator 66 further comprises a backbone 80 having radially extending backbone legs 82. The backbone legs 82 space one of the posts 70 from an adjacent post, and thus the number of backbone legs 82 is equal to the number of posts 70. The backbone legs 82 space the posts 70 from one another in the circumferential direction. Here, the backbone 80 is star-shaped. In the assembled state of the stator 66, the backbone 80 is sandwiched between the backplate 76 and the coil windings 72. The posts 70, the backplate 76 and the backbone 80 are made of a soft magnetic material, such as electromagnetic steel, or a suitable alloy, preferably cobalt steel. Preferably, the posts 70, the backplate 76 and the backbone 80 are made of the same material. In the illustrated embodiment, six posts 70 are provided, but the number of posts 70 is, of course, not limited to this.

[0039] The insulating assembly 68 includes a spacer 84, a front plate 86, and a front seat 88. The spacer 84 and the front plate 86 may be considered to constitute a spacer assembly 90. The spacer 84 has a tubular portion 92 extending in the circumferential and axial directions. In the assembled state of the drive unit 26, the spacer 84 is provided on the catheter end 78 of the stator 66, so that the backplate 76 and the backbone 80 are located radially inside the spacer 84. In particular, the outer peripheral surface of the backplate 76 and the outer peripheral surface of each of the backbone legs 82 contact the inner peripheral surface of the tubular portion 92 of the spacer 84. The outer peripheral surface of the tubular portion 92 abuts the inner surface of the drive unit casing 22, in particular the inner peripheral surface of the drive unit casing 22. The diameter of the spacer 84 is larger than the diameter of the stator 66. Furthermore, the printed circuit board 74 is partially housed by the spacer 84, as shown in FIG. 9.

[0040] The front plate 86 comprises a central portion 94 and a ring-shaped outer portion 96. The central portion 94 and the outer portion 96 are connected by front plate legs 98. The number of the front plate legs 98 is equal to the number of the posts 70. The front plate legs 98 circumferentially space the posts 70 from each other, in that the front plate 86 is provided at the impeller end 100 of the stator 66, i.e. at the end facing the impeller 20 in the assembled state of the drive unit 26. The front plate 86 has the same diameter as the diameter of the spacer 84, so that the outer peripheral surface of the outer portion 96 contacts the inner peripheral surface of the drive unit casing 22. The spacer 84 and the front plate 86 thus radially space the stator 66 from the inner peripheral surface of the drive unit casing 22, so that there is no radial contact between any part or member of the stator 66 and the drive unit casing 22.

[0041] Furthermore, the front sheet 88 covers an impeller-side end 100 of the stator 66 so as to suppress axial contact between the stator 66 and the drive unit casing 22. In particular, the front sheet 88 suppresses contact between the stator 66 and an impeller support portion 102 of the drive unit casing 22. The front sheet 88 is a foil-like member having a thickness of about 3 to 9 μm, preferably about 6 μm.

[0042] The spacer 84, front plate 86 and front sheet 88 are made of a non-conductive material that is also non-magnetic. Preferably, the spacer 84, front plate 86 and front sheet 88 are made of a thermoplastic material such as polyetheretherketone (PEEK).

[0043] Additionally, the insulation assembly 68 includes a plurality of contraction elements 104. In particular, each of the plurality of posts 70 is circumferentially surrounded by one of the contraction elements 104 to inhibit direct contact between the post 70 and the coil winding 72 surrounding the respective post 70. In other words, the contraction element 104 electrically isolates each post 70 from the respective coil winding 72. As shown in FIG. 10, it is not necessary for the contraction element 104 to extend along the entire axial extension of the post 70. Rather, it is sufficient if the contraction element 104 extends along about 50% or more of the axial extension of the respective post 70. In this embodiment, the contraction element 104 is a heat shrink sleeve constructed of polyester.

[0044] Essentially, the insulation assembly 68 significantly reduces leakage current in that contact between the stator 66 and any portion of the drive unit casing 22 is avoided. Additionally, further properties can be tailored in matching the dimensions of the various members of the insulation assembly 68. It is also possible to provide the front plate 86 and front sheet 88 as an integral, single member.

[0045] To further enhance leakage current reduction capabilities, the inner surface of the drive unit casing 22 may be partially or completely coated with a suitable coating, such as diamond-like carbon (DLC). Additionally, an additional constriction element may be provided that circumferentially surrounds the entire stator 66. Additionally or alternatively, the stator 66 may be circumferentially coated with a suitable coating, such as diamond-like carbon (DLC). Additionally, the plurality of posts 70, the backplate 76, and the backbone 80 may be partially or completely coated with a non-conductive material, particularly DLC.

[0046] The impeller support 102 comprises a tubular member 104, a film-like portion 106, and an ejector pin 108. The impeller support is one part of the drive unit casing 22 and is connected to another part, for example by gluing or press-fitting. In particular, the tubular member 104 is connected to a connection portion 110 of another part of the drive unit casing 22.

[0047] The film-like portion 106 can contact the front sheet 88 of the insulating assembly 68. The film-like portion 106 has a thickness of only about 60 to 80 μm, preferably 70 μm. The protruding pin 108 protrudes from the film-like portion 106 in a direction toward the impeller 20. The main axis of the protruding pin 108 is concentric with the axis of rotation X. In this embodiment, the protruding pin 108 is integrally formed with the film-like portion 106 in that a rounded, smooth transition 112 is formed between the film-like portion 106 and the protruding pin 108 to reduce mechanical stress during rotation of the impeller 20. The protruding pin 108 further supports a part of the pivot bearing 40, namely the second pivot bearing member 120, as will be described in more detail below. The second pivot bearing member 120 can be glued or press-fitted onto the protruding pin 108.

[0048] Due to the relatively small thickness of the film-like portion 106, the mechanical stability of the film-like portion 106 is not as high as that of the tubular member 104 of the impeller support 102. Therefore, the drive unit casing 22 is at least partially filled with the potting material 114. In particular, the potting material 114 can cover the stator 66 and the insulating assembly 68, and thus fill the drive unit casing 22 at least between the impeller support 102 and the printed circuit board 74. The potting material 114 reinforces the film-like portion 106 from the inside of the drive unit casing 22 to reduce the risk of stress cracks and the like.

[0049] To further reinforce the impeller support 102, a reinforcing member 116, which is an alternative embodiment of the impeller support 102, may be provided as shown in FIG. 11. The reinforcing member 116 protrudes from the film-like portion 106 of the impeller support 102 in a direction toward the stator 66. In this embodiment, the reinforcing member 116 is a pin-like member formed integrally with the film-like portion 106. In the assembled state of the blood pump 10, the reinforcing member 116 protrudes into the stator 66 and is surrounded by the potting material 114. Thus, the potting material 114 further stiffens and reinforces the film-like portion 106.

[0050] In this embodiment, the potting material 114 is preferably a material with FDA approval. Preferably, the potting material is a mixture of epoxy resin and metal oxide, such as aluminum oxide. For example, a mixture of EpoTek® 301 and Al2O3 powder can be used. Preferably, a ratio of 1:1.5 of EpoTek® 301 and Al2O3 powder is used.

[0051] Bearing device The bearing assemblies 40, 42 will now be described in more detail.

[0052] 12, a first bearing 40 in the form of a pivot bearing 40 is described. The pivot bearing 40 comprises a first bearing member, which is a first pivot bearing member 118, and a second bearing member, which is a second pivot bearing member 120. The first pivot bearing member 118 is attached to the impeller 20. In particular, the first pivot bearing member 118 is disposed in the bearing housing 44 of the impeller 20. The second pivot bearing member 120 is received in the axial end of the protruding pin 108. The first pivot bearing member 118 can be glued or press-fitted into the bearing housing 44. The second pivot bearing member 120 can be glued or press-fitted into the protruding pin 108.

[0053] The first pivot bearing member 118 comprises a first abutment portion 122 having a spherical portion with a convex surface. In the embodiment shown in Fig. 12, the spherical portion 124 is part of a ball 126 connected to a pin-like support element 128 of the first pivot bearing member 118. In this embodiment, the ball 126 is fixed to the support element 128 by a mounting pin 130, although the spherical portion 124 could also be formed integrally with the support element 128, as shown for example in Fig. 13 or 14.

[0054] The second pivot bearing member 120 comprises a second abutment portion 132 having a first spherical cap 134 with a concave surface. The first spherical cap 134 may be a first carrot. The first abutment portion 122 abuts the second abutment portion 132 in that the spherical portion 124 contacts the first spherical cap 134. The contact between the spherical portion 124 and the first spherical cap 134 may be a point contact, since the spherical portion 124 may have a first radius that is smaller than the second radius of the first spherical cap 134. The point contact may reduce the overall wear and mechanical stress during the rotation of the impeller 20.

[0055] In an alternative embodiment shown in Fig. 15, the ball 126 is not fixed to the support element 128 but is supported in a second spherical cap 136 provided at the axial end of the support element 128. The second spherical cap 136 also comprises a concave surface having a third radius larger than the first radius of the spherical portion 124 or the ball 126, respectively. The contact between the ball 126 and the second spherical cap 136 may therefore also be a point contact, which again makes it possible to reduce mechanical stresses during rotation of the impeller 20.

[0056] As shown in the alternative embodiment according to Fig. 13, the first abutment portion 122 may comprise a plurality of first notches 138 evenly distributed along the circumference of the first abutment portion 122. As shown, the first notches 138 have an axial extension parallel to the axial extension of the support element 128. Furthermore, each of the first notches 138 tapers from the first abutment portion 122 towards another axial end of the support element 128. In particular, the first notches 138 are inclined towards the central axis of the support element 128, which is concentric with the rotation axis X of the impeller 20.

[0057] In figures 16 to 18 an alternative embodiment of the second pivot bearing member 120 is shown. The second abutment part 132 of the embodiment shown in figures 17 and 18 can be provided with second cutouts 140, whereas the abutment part 132 of the embodiment shown in figure 16 does not have any cutouts. In the embodiment according to figure 17, the second cutouts 140 are evenly distributed along the circumference of the second abutment part 132. The axial extension of the second cutouts 140 is non-parallel to the central axis of the second pivot bearing member 120, whereas the latter is concentric with the axis of rotation X of the impeller 20.

[0058] In an alternative embodiment shown in Figure 18, the second notch 140 has an axial extension that is parallel to the central axis of the second pivot bearing member 120. Additionally, the second notch 140 in the embodiment shown in Figure 18 may be tapered along the axial extension and angled relative to the central axis of the second pivot bearing member 120.

[0059] In the illustrated embodiment, a total of three first cutouts 138 and three second cutouts 140 are provided. However, the number of cutouts may be different between the first abutment portion 122 and the second abutment portion 132. Furthermore, more or less than three first cutouts 138 and second cutouts 140 may be provided. Furthermore, it is also possible that only one of the first abutment portion 122 and the second abutment portion 132 has a cutout.

[0060] The first notch 138 and the second notch 140 are intended to promote blood flow as the impeller 20 rotates, so that the pivot bearing 40 may be cooled. Additionally, the first notch 138 and the second notch 140 improve the rinsing ability of the pivot bearing 40, thus preventing the accumulation of blood particles, i.e., blood clotting.

[0061] As mentioned above, the impeller 20 includes an opening 60 having a central axis CA facing the pivot bearing 40. In particular, the central axis CA of the opening 60 faces the first abutment portion 122 or the second abutment portion 132, respectively. Thus, the blood after passing through the opening 60 is directed toward the contact area between the first abutment portion 122 and the second abutment portion 132, so as to cool and rinse the contact area between the first abutment portion 122 and the second abutment portion 132.

[0062] To further enhance the cooling, a first hollow portion 142 in the first pivot bearing member 118 may be provided (see FIG. 14). The first hollow portion 142 is filled with a material having a higher thermal conductivity than the material of the first pivot bearing member 118. In the illustrated embodiment, a pin-shaped first cooling member 144 is disposed in the first hollow portion 142. The first cooling member 144 absorbs a portion of the heat generated in the first abutment portion 122 as the impeller 20 rotates and distributes the heat along the axial extension of the impeller 20.

[0063] The second pivot bearing member 120 may include a second hollow portion 146. The second hollow portion 146 is filled with a material having a higher thermal conductivity than the material of the second pivot bearing member 120. In the illustrated embodiment, a pin-shaped second cooling member 148 is disposed in the second hollow portion 146. The second cooling member 148 absorbs a portion of the heat generated in the second abutment portion 132 when the impeller 20 rotates and distributes the heat along the axial extension of the protruding pin 108.

[0064] The first pivot bearing member 118 may be entirely or partially composed of a first ceramic material selected from silicon carbide (SIC), alumina-toughened zirconia (ATZ), zirconia-toughened alumina (ZTA) or aluminium oxide (Al2O3). Alternatively, the first pivot bearing member 118 may be entirely or partially composed of a metallic material such as a cemented carbide. The metallic material may be further coated with a first ceramic material. The metallic material or the first ceramic material may be further coated with DLC. The DLC coating may include a boron-doped DLC film. The boron-doped DLC film may be disposed on a non-boron-doped DLC interlayer to improve adhesion. Alternatively, the first pivot bearing member 118 may be entirely or partially composed of diamond.

[0065] The second pivot bearing member 120 may be entirely or partially composed of a second ceramic material selected from SIC, ATZ, ZTA, or Al2O3. Additionally, the second pivot bearing member 120 may be entirely or partially composed of a metallic material, such as a cemented carbide. The metallic material may be further coated with a second ceramic material. The metallic material or the second ceramic material may be further coated with DLC. The DLC coating may include a boron-doped DLC film. The boron-doped DLC film may be disposed on a non-boron-doped DLC interlayer to improve adhesion. Alternatively, the second pivot bearing member 120 may be entirely or partially composed of diamond.

[0066] If a ball 126 is provided, the ball may be constructed entirely or partially of a third ceramic material selected from SIC, ATZ, ZTA, or Al2O3. Additionally, the ball 126 may be constructed entirely or partially of a metallic material, such as a cemented carbide. The metallic material may be further coated with a third ceramic material. The metallic material or the third ceramic material may be further coated with DLC. The DLC coating may include a boron doped DLC film. The boron doped DLC film may be disposed on a non-boron doped DLC interlayer to improve adhesion. Alternatively, the ball 126 may be constructed entirely or partially of diamond.

[0067] The first ceramic material, the second ceramic material, and the third ceramic material may be different or the same. The following material combinations shown in Table 1 have proven to be particularly suitable with respect to heat transfer, wear, friction, rinsability, and prevention of blood particle adhesion: [Table 1]

[0068] Preferably, the first ceramic material of the first pivot bearing member 118 is ZTA and the second ceramic material of the second pivot bearing member 120 is ATZ.

[0069] As mentioned above, the first cooling member 144 and the second cooling member 148 are made of a material having a higher thermal conductivity than the respective materials of the first pivot bearing member 118 and the second pivot bearing member 120. In particular, the first cooling member 144 and the second cooling member 148 are made of either silver, a silver alloy, copper, or a copper alloy.

[0070] Of course, although the above describes the first pivot bearing member 118 comprising the spherical portion 124 and the second pivot bearing member 120 comprising the first spherical cap 134, the arrangement may be twisted in that the first pivot bearing member 118 comprises the first spherical cap and the second pivot bearing member 120 comprises the spherical portion. A corresponding embodiment is shown in Figures 19-21 and described below.

[0071] 19 and 20, the first pivot bearing member 118 may comprise a first abutment portion 122 having a concave surface, i.e., a first spherical cap 134 or a first carrot, respectively. Accordingly, the second pivot bearing member 120 may comprise a second abutment portion 132 having a convex surface, i.e., a spherical portion 124.

[0072] The support element 128 comprises a slot 149 extending from the first abutment 122. At the end of the support element 128 facing the first abutment 122, the slot 149 extends across the entire diameter of the support element 128, thus dividing the first spherical cap 134 into two parts (see FIG. 21).

[0073] The slot 149 is configured such that a rotation of the first pivot bearing member 118 and / or the support element 128 results in a pumping action from one side of the slot 149 to the other side of the slot. The slot 149 is bounded by two parallel sides. Preferably, the two sides are parallel to each other and / or to the mid-plane of the support element 128. The slot 149 does not extend over the entire diameter of the support element 128 over its entire length. In a first section of the slot 149 facing the first abutment 122, the slot 149 extends over the entire diameter of the support element 128 (see Figures 19 and 21). Thus, in the first section of the slot 149, the slot 149 extends on both sides of the support element 128. In a second section of the slot 149, the slot extends only to one side of the support element 128. In particular, the slot width of the slot gradually narrows in a direction away from the first abutment portion 122.

[0074] The support element 128 tapers axially from the first abutment portion 122 towards the radial bearing 42. In particular, the diameter of the support element 128 is larger along the axial extension of the slot 149. Of course, the support element 128 may also have a cylindrical shape.

[0075] Furthermore, the central axis CA of the opening 60 points towards the slot 149. During rotation of the impeller 20, blood enters the bearing housing 44 through the opening 60 and is directed in the slot 149 towards the second pivot bearing member 120. The contact area is cooled and rinsed as it exits the slot 149 on the side of the support element 128 in the contact area of ​​the first abutment portion 122 and the second abutment portion 132.

[0076] Preferably, in the embodiment shown in Figures 19-21, the first ceramic material of the first pivot bearing member 118 is ATZ and the second ceramic material of the second pivot bearing member 120 is ZTA.

[0077] Furthermore, the first abutment portion 122 may be coated with a diamond coating. In this regard, the second abutment portion 132 may also be coated with a diamond coating. The diamond coating may be a chemical vapor deposition (CVD) diamond coating. The diamond coating may be applied directly onto a ceramic material as described above. Of course, the diamond coating may also be applied onto the first abutment portion 122 or the second abutment portion 132, respectively, made of another material, for example titanium, a titanium alloy or stainless steel.

[0078] Next, the radial bearing 42 will be described in more detail.

[0079] 22 shows the radial bearing 42 in more detail in a perspective view and in a partially cutaway view. The radial bearing 42 comprises a first radial bearing member 150 and a second radial bearing member 152. The first radial bearing member 150 is arranged at the axial end of the impeller 20 facing towards the crown 46. The first radial bearing member 150 can be glued or pressed into the impeller 20. The first radial bearing member 150 is approximately cylindrical and comprises a collar 154 in the form of a circumferential projection. Furthermore, the first radial bearing member 150 comprises third notches 156 evenly distributed in the circumferential direction along the outer peripheral surface of the first radial bearing member 150.

[0080] 22, the third notch 156 has an axial extension that is not parallel to the central axis of the first radial bearing member 150, which is concentric with the axis of rotation X of the impeller 20. In the illustrated embodiment, a total of two third notches 156 are provided.

[0081] The outer circumferential surface of the body 56 of the impeller 20 also includes a corresponding impeller notch 158 that smoothly extends the third notch 156. The collar 154 abuts the body 56 of the impeller 20 to limit axial movement of the first radial bearing member 150 in the axial direction toward the stator 66.

[0082] The second radial bearing member 152 is a ring-shaped member disposed in the central tubular portion 48 of the crown 46 (see FIGS. 22 and 23). The second radial bearing member 152 may be glued or press-fitted into the central tubular portion 48 of the crown 46. As shown in FIG. 24, the second radial bearing member 152 includes a plurality of fourth notches 160 evenly spaced circumferentially around the second radial bearing member 152. As shown, the fourth notches 160 extend radially through the second radial bearing member 152, with the open ends of the fourth notches 160 facing towards the impeller 20. In this embodiment, three fourth notches 160 are provided. The circumferential extension of each of the fourth notches 160 is smaller than the circumferential distance between the third notches 156 of the first bearing member 150, ensuring that the first bearing member 150 is safely supported by the second bearing member 152 in the assembled state of the radial bearing 42.

[0083] The third notch 156, the impeller notch 158, and the fourth notch 160 are provided to cool the radial bearing by directing a portion of the blood flow along the respective notches as the impeller 20 rotates, thereby further preventing the accumulation of blood particles in the area of ​​the radial bearing 42.

[0084] Moreover, the collar 154 does not contact the second radial bearing member 152 in the assembled state of the radial bearing 42. Rather, a gap G is formed axially between the collar 154 and the second radial bearing member 152 during normal operating conditions of the blood pump 10 (see FIG. 23). Even when the impeller 20 rotates to convey blood from the blood inlet 14 to the blood outlet 16, there is no contact between the collar 154 and the second radial bearing member 152 due to the attractive force between the stator 66 and the magnet 52 of the impeller 20. In other words, the attractive force acts in the direction of the stator 66 so that the impeller 20 does not move axially when rotating. However, the collar 154 forms an emergency stop to limit the axial movement of the impeller 20 away from the stator 66 in case of a fault.

[0085] The first radial bearing member 150 and the second radial bearing member 152 may be made of a ceramic material, a metallic material or diamond. The ceramic material may be SIC, ATZ, ZTA or Al2O3. The ceramic materials of the first radial bearing member 150 and the second radial bearing member 152 may be the same or different. Furthermore, the ceramic material may be provided as a coating when the first radial bearing member 150 and / or the second radial bearing member 152 are made of a metallic material, in particular a cemented carbide. Furthermore, the metallic or ceramic material may be coated with DLC. The DLC coating may include a boron-doped DLC film. The boron-doped DLC film may be disposed on a non-boron-doped DLC intermediate layer to improve adhesion. The following combinations of materials have been found to be particularly preferred: SIC and SIC, ATZ and Al2O3, ATZ and ZTA, and ATZ and ZTA coated with DLC.

[0086] Preferably, the ceramic material of the first radial bearing member 150 is ZTA and the ceramic material of the second radial bearing member 152 is ATZ.

[0087] Furthermore, the first radial bearing member 150 may be coated with a diamond coating. In this regard, the second radial bearing member 152 may also be coated with a diamond coating. The diamond coating may be a chemical vapor deposition (CVD) diamond coating. The diamond coating may be applied directly onto a ceramic material as described above. Of course, the diamond coating may also be applied onto the first radial bearing member 150 or the second radial bearing member 152, each made of another material, for example, titanium, a titanium alloy, or stainless steel.

[0088] Coating a ceramic material with DLC generally has the advantage that, for example, even if the DLC coating is damaged or removed by wear, the bearing arrangement 40, 42 has relatively high emergency running characteristics. Diamond coatings generally have the advantage of being highly wear resistant and biocompatible.

[0089] Function of the blood pump A controller including a printed circuit board 74 generates a rotating magnetic field in the stator 66 in a known manner that cooperates with the magnets 52 of the impeller 20 to rotate the impeller 20 about the axis of rotation X. This causes the primary blades 54 of the impeller 20 to generate a primary blood flow from the blood flow inlet 14 through the passages 18 to the blood flow outlet 16. A portion of the primary blood flow is directed along the radial bearing 42 along the third notch 156, the impeller notch 158 and the fourth notch 160 to cool and rinse the radial bearing 42 and prevent blood particle buildup in the area of ​​the radial bearing 42.

[0090] The secondary blades 64 of the impeller 20 create a secondary blood flow, and blood is drawn from the passage 18 through the opening 60 and into the bearing housing 44. There, the secondary blood flow is directed along either the first notch 138 and the second notch 140 (if provided) or along the slot 149 to cool and rinse the pivot bearing 40 and prevent blood particle build-up in the area of ​​the pivot bearing 40. The secondary blood flow then exits the bearing housing 44 through the space formed between the impeller 20 and the impeller support 102 and exits the blood pump 10 through the blood flow outlet 16.

[0091] Exemplary Implementations As previously discussed, the techniques described herein can be implemented in a variety of ways. In that regard, the foregoing disclosure is intended to include, but is not limited to, the systems, methods, and combinations and subcombinations thereof described in the following exemplary implementations. Preferred embodiments are described in the following paragraphs. A1 A blood pump, in particular an intravascular blood pump, characterized in that it comprises a pump housing having a blood flow inlet and a blood flow outlet connected by a passage, an impeller arranged within the pump housing, and a drive unit configured to drive the impeller. A2. A blood pump as described in paragraph A1, wherein the pump housing comprises a drive unit casing, the drive unit is disposed within the drive unit casing, the drive unit comprises a stator and an insulating assembly, and the insulating assembly is configured to prevent electrical leakage. A3. The blood pump of paragraph A2, wherein the insulation assembly comprises a spacer assembly configured to space the stator from the drive unit casing to inhibit contact between the stator and the drive unit casing. A4. A blood pump as described in paragraph A3, characterized in that the spacer assembly comprises a spacer configured to radially space the stator from an inner surface of the drive unit casing, in particular an inner circumferential surface of the drive unit casing. A5. A blood pump according to paragraph A4, characterized in that the stator has a catheter end facing away from the impeller, the spacer is ring-shaped and has a tubular portion, the tubular portion extending at least partially in a circumferential direction, and the spacer is arranged at the catheter end of the stator such that the stator is arranged partially radially inside the tubular portion of the spacer. A6. A blood pump as claimed in paragraph A5, characterized in that the tubular portion of the spacer abuts the inner surface of the drive unit casing. A7. A blood pump as described in paragraph A5 or A6, wherein the stator comprises a backplate contacting the catheter end of the stator, the backplate being disposed radially inward of the tubular portion of the spacer. A8. A blood pump according to any one of paragraphs A3 to A7, wherein the drive unit further comprises a printed circuit board, the printed circuit board being at least partially disposed radially within the spacer assembly. A9. The blood pump of any one of paragraphs A2-A8, wherein the insulation assembly comprises a front plate configured to space the stator from the drive unit casing to inhibit contact between the stator and the drive unit casing. A10. The blood pump of paragraph A9, wherein the stator comprises a plurality of posts and coil windings disposed about the posts, the front plate having a central portion and an outer portion, and a plurality of front plate legs extending between the central portion and the ring-shaped outer portion. A11. A blood pump as described in paragraph A10, characterized in that the front plate legs are configured to circumferentially space each of the plurality of posts from adjacent posts, and the plurality of posts are disposed partially radially inward of a ring-shaped outer portion, the outer portion preferably being ring-shaped. A12. A blood pump according to any one of paragraphs A1 to A11, wherein the stator comprises a plurality of posts and a coil winding disposed around the posts. A13. A blood pump according to any one of paragraphs A10 to A12, wherein the stator comprises a backbone having radially extending backbone legs, the backbone legs preferably configured to circumferentially space each of the plurality of posts from an adjacent post. A14. A blood pump according to any one of paragraphs A10 to A13, wherein the insulating assembly comprises a plurality of contraction elements, and each of the plurality of posts is at least partially surrounded by one of the contraction elements. A15. A blood pump according to any one of paragraphs A2 to A14, characterized in that the stator has an impeller-side end facing the impeller, and the insulation assembly further comprises a front sheet, the front sheet covering the impeller-side end of the stator so as to inhibit contact between the stator and the drive unit casing. A16. A blood pump according to any one of paragraphs A2 to A15, characterized in that the insulating assembly is at least partially constructed of a non-conductive material, and the insulating assembly is preferably entirely constructed of a non-conductive material. A17. A blood pump according to paragraph A16, characterized in that the non-conductive material is a thermoplastic material, preferably a polyaryletherketone, and the non-conductive material is preferably a polyetheretherketone. A18. A blood pump according to any one of paragraphs A1 to A17, characterized in that the drive unit casing is made of titanium or a titanium alloy. A19. A blood pump according to any one of paragraphs A1 to A18, characterized in that the inner surface of the drive unit casing is at least partially coated with a non-conductive coating, in particular diamond-like carbon (DLC). A20. A blood pump according to any one of paragraphs A1 to A19, characterized in that the stator is at least partially surrounded in the circumferential direction by the contractile element and / or the stator is at least partially coated with a non-conductive coating. A21. A blood pump according to any one of paragraphs A1 to A20, characterized in that the blood pump further comprises a bearing device for rotatably supporting the impeller, the bearing device comprising at least one bearing comprising a first bearing member and a second bearing member, the first bearing member comprising a first abutment portion, the second bearing member comprising a second abutment portion, the first abutment portion comprising or made of a first ceramic material, and / or the second abutment portion comprising or made of a second ceramic material. A22. A blood pump according to paragraph A21, wherein the first ceramic material is different from the second ceramic material or the first ceramic material is the same as the second ceramic material. A23. A blood pump as described in paragraph A21 or A22, wherein the first bearing member is constructed entirely of a first ceramic material and / or the second bearing member is constructed entirely of a second ceramic material. A24. A blood pump according to paragraph A21 or A22, characterized in that the first abutment part is made of a metallic material, in particular a hard metal, coated with a first ceramic material and / or the second abutment part is made of a metallic material, in particular a hard metal, coated with a second ceramic material. A25. A blood pump according to any one of paragraphs A21 to A24, characterized in that the first contact portion is coated with diamond-like carbon (DLC) and / or the second contact portion is coated with diamond-like carbon (DLC). A26. A blood pump according to any one of paragraphs A21 to A25, wherein the first ceramic material is selected from SIC, ATZ, ZTA or Al2O3. A27. A blood pump according to any one of paragraphs A21 to A26, wherein the second ceramic material is selected from SIC, ATZ, ZTA or Al2O3. A28. A blood pump according to any one of paragraphs A21 to A27, characterized in that the first bearing member is at least partially constructed from diamond or the second bearing member is at least partially constructed from diamond. A29. The blood pump according to any one of paragraphs A1 to A19, further comprising a bearing device for rotatably supporting the impeller, the bearing device comprising at least a first bearing comprising a first bearing member and a second bearing member, the first bearing member comprising a first abutment portion, the second bearing member comprising a second abutment portion, the first abutment portion being coated with DLC and / or the second abutment portion being coated with DLC. A30. A blood pump according to any one of paragraphs A25 to A29, wherein the DLC coating comprises or consists of a boron doped DLC film. A31. A blood pump according to any one of paragraphs A30, wherein the DLC coating comprises a DLC intermediate layer, and the boron-doped DLC film is disposed on the DLC intermediate layer. A32. A blood pump according to paragraph A30 or A31, characterized in that the boron doped DLC membrane comprises a boron to carbon ratio of 0.01 to 0.4, preferably 0.03 to 0.1, most preferably 0.03. A33. A blood pump according to any one of paragraphs A1 to A19, further comprising a bearing device for rotatably supporting the impeller, the bearing device comprising at least a first bearing comprising a first bearing member and a second bearing member, the first bearing member comprising a first abutment portion, the second bearing member comprising a second abutment portion, the first abutment portion being coated with a diamond coating and / or the second abutment portion being coated with a diamond coating. A34. A blood pump according to paragraph A33, characterised in that the diamond coating is a chemical vapor deposition (CVD) diamond coating or a high pressure, high temperature (HPHT) diamond coating. A35. A blood pump according to any one of the preceding paragraphs A21 to A34, characterized in that the first contact portion at least partially contacts the second contact portion. A36. A blood pump according to paragraph A35, characterized in that the contact between the first abutment part and the second abutment part is a point contact. A37. A blood pump according to any one of paragraphs A21 to A36, characterized in that the first bearing member comprises a support element and a ball, the support element comprises a first abutment portion, and the ball abuts against the first abutment portion and the second abutment portion. A38. A blood pump according to paragraph A37, characterized in that the ball comprises or is made of a third ceramic material, the third ceramic material being selected from SIC, ATZ, ZTA or Al2O3. A39. A blood pump according to paragraph A37, characterised in that the balls comprise or consist of a metallic material, in particular a hard metal. A40. A blood pump according to any one of paragraphs A37 to A39, wherein the ball is coated with diamond-like carbon (DLC). A41. A blood pump according to paragraph A37, characterised in that the ball comprises or consists of diamond. A42. A blood pump according to any one of paragraphs A21 to A41, characterized in that the first bearing member comprises a first hollow portion filled with a material having a higher thermal conductivity than a material of the first bearing member and / or the second bearing member comprises a second hollow portion filled with a material having a higher thermal conductivity than a material of the second bearing member, the material having high thermal conductivity being preferably one of silver, a silver alloy, copper, a copper alloy and diamond. A43. A blood pump according to any one of paragraphs A21 to A42, characterized in that the bearing device comprises a first bearing and a second bearing. A44. A blood pump according to paragraph A43, characterized in that the first bearing is a pivot bearing and the second bearing is a radial bearing. A45. A blood pump according to any one of paragraphs A1 to A44, characterized in that the blood pump further comprises a bearing device for rotatably supporting the impeller, the bearing device comprising at least one pivot bearing. A46. A blood pump according to paragraph A45, characterized in that the pivot bearing comprises a first pivot bearing member and a second pivot bearing member, the first pivot bearing member being pivotable relative to the second pivot bearing member, the first pivot bearing member comprising a first abutment portion and the second pivot bearing member comprising a second abutment portion, the first abutment portion of the first pivot bearing member at least partially contacting the second abutment portion of the second pivot bearing member. A47. A blood pump according to paragraph A46, characterized in that the contact between the first abutment portion of the first pivot bearing member and the second abutment portion of the second pivot bearing member is a point contact. A48. A blood pump according to paragraph A46 or A47, characterized in that the first abutment portion of the first pivot bearing member comprises a spherical portion and the second abutment portion of the second pivot bearing member comprises a first spherical cap, the spherical portion abutting against the spherical cap. A49. A blood pump according to paragraph A48, characterized in that the first spherical cap is a first carrot. A50. A blood pump according to paragraph A48 or A49, characterized in that the first spherical cap has a concave surface and / or the bulb has a convex surface. A51. A blood pump according to any one of paragraphs A48 to A50, characterized in that the spherical portion has a first radius, the first spherical cap has a second radius, and the second radius is greater than the first radius. A52 A blood pump according to any one of paragraphs A48 to A50, characterized in that the first pivot bearing member comprises a support element and a ball, the ball abutting the support element and comprising a spherical portion. A53. A blood pump according to paragraph A52, characterized in that the support element comprises a second spherical cap having a third radius, the ball abutting the second spherical cap, the third radius being greater than the first radius. A54. A blood pump according to paragraph A53, characterized in that the second spherical cap is a second carrot. A55. A blood pump according to paragraph A53 or A54, characterized in that the second spherical cap has a concave surface. A56. A blood pump according to any one of paragraphs A52 to A55, characterized in that the ball is fixed to a support element. A57. A blood pump according to any one of paragraphs A46 to A56, characterized in that the first abutment portion of the first pivot bearing member comprises at least one first notch, preferably a plurality of first notches evenly distributed along the circumference of the first abutment portion. A58. A blood pump according to any one of paragraphs A46 to A57, characterized in that the second abutment portion of the second pivot bearing member comprises at least one second notch, preferably a plurality of second notches evenly distributed along the circumference of the second abutment portion. A59. A blood pump according to paragraph A58, characterized in that the axial extension of the at least one second notch is non-parallel to a main axis of the second pivot-bearing member, and the axial extension of the at least one second notch is parallel to a main axis of the second pivot-bearing member. A60. A blood pump as described in paragraph A46, wherein the first pivot bearing member includes a slot extending from the first abutment portion. A61. A blood pump according to paragraph A60, characterized in that a slot divides the first abutment portion of the first pivot bearing member into two portions. A62. A blood pump according to paragraph A60 or A61, wherein the slot is configured such that rotation of the first pivot bearing member causes pumping action from one side of the slot to the other side of the slot. A63. A blood pump according to any one of paragraphs A60 to A62, characterized in that: a) the slot is bounded by two parallel sides, the two sides being preferably parallel to each other and / or parallel to the mid-plane of the support element; and / or b) A blood pump characterized in that the slot does not extend over the entire diameter of the support element over its entire length. A64. A blood pump according to any one of paragraphs A46 to A63, characterized in that the impeller has a bearing receiving part on its inner side and at least one opening connecting the passage with the bearing receiving part, and the pivot bearing is at least partially arranged in the bearing receiving part. A65. A blood pump according to paragraph A64, characterized in that the blood pump has a central axis with an opening facing towards the second abutment portion of the second pivot bearing member. A66. A blood pump according to paragraph A64 or A65, characterized in that the impeller comprises a body and at least one primary blade helically projecting from an outer circumferential surface of the body, and the opening comprises an inlet provided on the outer circumferential surface of the body, and at least a portion of the at least one primary blade is disposed circumferentially of the body tangent to the inlet. A67. A blood pump according to paragraph A66, characterized in that the inlet is arranged circumferentially within the axial extension of at least one primary blade. A68. A blood pump according to any one of paragraphs A46 to A67, characterized in that the first pivot bearing member is mounted on the impeller and the second pivot bearing member is mounted on the pump housing. A69. The blood pump of any one of paragraphs A45 to A68, wherein the bearing arrangement further comprises at least one radial bearing, the pivot bearing rotatably supports the impeller relative to the housing at one point on the impeller and the radial bearing rotatably supports the impeller relative to the housing at another point on the impeller, and the drive unit is a non-contact electromagnetic drive unit configured to rotatably drive the impeller relative to the housing, and the drive unit further establishes an attractive force on the impeller. A70. A blood pump according to paragraph A69, characterized in that a gravitational force is established in a direction away from the blood inlet, so that no axial force acts on the radial bearing. A71. A blood pump according to paragraph A59 or A70, characterized in that the radial bearing comprises a first radial bearing member and a second radial bearing member, the first radial bearing member being attached to the impeller and the second radial bearing member being attached to the pump housing, the first radial bearing member comprising a collar, the collar extending at least partially circumferentially from an outer circumferential surface of the first radial bearing member, the collar being disposed adjacent the second radial bearing member, and a gap being formed axially between the collar and the second radial bearing member. A72. A blood pump according to paragraph A71, characterised in that no axial forces act on the collar. A73. A blood pump according to paragraph A71 or A72, characterized in that the collar is an emergency abutment collar limiting axial movement of the impeller relative to the housing. A74. A blood pump according to any one of paragraphs A45 to A73, characterized in that the pivot bearing members are attached by gluing and / or press-fitting and / or the radial bearing members are attached by gluing and / or press-fitting. A75. A blood pump according to any one of paragraphs A1 to A74, characterized in that the blood pump further comprises a stator, and the pump housing comprises a drive unit casing having a catheter mounting portion at one axial end and an impeller support portion at another axial end, the stator being disposed within the drive unit casing, and the drive unit casing being at least partially filled with potting material. A76. A blood pump according to paragraph A75, wherein the potting material contacts the impeller support. A77. A blood pump according to paragraph A76, characterized in that the potting material comprises an epoxy resin, preferably a mixture of epoxy resin and aluminium oxide, preferably a mixture of EpoTek® 301 and Al2O3 powder, preferably in a ratio of 1:1.5. A78. A blood pump according to any one of paragraphs A75 to A77, characterized in that the impeller support portion comprises a film-like portion and a protruding pin, and the protruding pin is configured to rotatably support the impeller. A79. A blood pump according to paragraph A78, characterized in that the film-like portion has a thickness of 60 μm to 80 μm, preferably 70 μm. A80. A blood pump according to paragraph A78 or A79, characterized in that the protruding pin is integrally formed with the film-like portion. A81. The blood pump according to any one of paragraphs A78 to A80, wherein the central axis of the ejector pin is concentric with the rotation axis of the impeller. A82. A blood pump according to any one of paragraphs A78 to A81, characterized in that a rounded transition is provided between the film-like portion and the protruding pin. A83. A blood pump according to any one of paragraphs A75 to A82, characterized in that at least one reinforcing member protrudes from the impeller support in the direction of the catheter attachment, the reinforcing member preferably protruding into the interior of the drive unit casing. A84. A blood pump according to paragraph A83, characterized in that the reinforcing member protrudes in the axial direction, and the potting material hardens the film-like portion. A85. The blood pump of paragraph A83 or A84, wherein the potting material surrounds at least one reinforcing member. A86. A blood pump according to any one of paragraphs A83 to A85, wherein at least one reinforcing member is concentric with the axis of rotation of the impeller. A87. A blood pump according to any one of paragraphs A1 to A86, characterized in that the pump housing comprises a drive unit casing, the impeller has at least one primary blade configured to establish a primary blood flow, the impeller has a casing end, the casing end facing towards the drive unit casing, and a plurality of secondary blades are provided on the casing end configured to establish a secondary blood flow. A88. A blood pump according to paragraph A87, wherein the impeller has an axis of rotation, and each of the secondary blades extends non-radially relative to the axis of rotation. A89. A blood pump according to paragraph A87 or A88, wherein each of the secondary blades has a base point and an end point, the base point being located on a base circle and the end point being located on an end circle, the base circle and the end circle being concentric about a common centre point, and no straight line connecting the base circle and the end circle of any one of the secondary blades extends through the centre point. A90. The blood pump of paragraph A89, wherein each of the plurality of secondary blades is curved relative to a respective straight line. A91. A blood pump according to any one of paragraphs A1 to A90, characterized in that the pump housing comprises a catheter mounting portion, the catheter mounting portion comprising a threaded structure on an outer circumferential surface configured for threaded engagement with a helical member of a catheter of the blood pump. A92. A blood pump as described in paragraph A91, characterized in that the blood pump comprises a catheter having a helical member, the catheter being attached to the catheter attachment portion in that the helical member is in threaded engagement with the threaded structure, the helical member being preferably a Nitinol coil.

[0092] As used herein, the terms "approximately," "about," "substantially," and similar terms are intended to have broad meanings consistent with common usage accepted by those skilled in the art to which the subject matter of this disclosure belongs. It should be understood by those skilled in the art who review this disclosure that these terms are intended to enable the description of the particular features being described without limiting the scope of those features to the precise numerical ranges provided. Thus, these terms should be interpreted as indicating that insubstantial or insignificant modifications or alterations of the subject matter being described are considered to fall within the scope of this disclosure. As used herein, the terms "at least partially" or "partially" have both a partial meaning and a whole or complete meaning, respectively. [Explanation of symbols]

[0093] 10 blood pump, 12 pump housing, 14 blood flow inlet, 16 blood flow outlet, 18 passageway, 20 impeller, 22 drive unit casing, 24 impeller casing, 26 drive unit, 28 cannula attachment, 30 catheter, 32 catheter attachment, 34 tubular portion of catheter attachment, 36 threaded structure, 38 helical member / nitinol coil, 40 first bearing / pivot bearing, 42 second bearing / radial bearing, 44 bearing housing, 46 crown, 48 central tubular portion of crown, 50 connecting arm, 52 magnet, 54 primary blade, 56 body of impeller, 58 opening, 60 inlet, 62 casing end of impeller, 64 secondary blade, 65 secondary auxiliary blade, 66 Stator, 68, insulation assembly, 70, post, 72, coil winding, 74, controller / printed circuit board, 76, backplate, 78, catheter end of stator, 80, backbone, 82, backbone legs, 84, spacer, 86, front plate, 88, front sheet, 90, spacer assembly, 92, spacer tubular section, 94, front plate central section, 96, front plate outer section, 98, front plate legs, 100, impeller end of stator, 102, impeller support, 104, impeller support tubular section, 106, film section, 108, protruding pin, 110, connection section, 112, transition section, 114, potting material, 116, reinforcing member, 118, first bearing member / first pivot bearing member, 120 second bearing member / second pivot bearing member, 122 first abutment portion, 124 spherical portion, 126 ball, 128 support element, 130 mounting pin, 132 second abutment portion, 134 first spherical cap / first carrot, 136 second spherical cap / second carrot, 138 first notch, 140 second notch, 142 first hollow portion, 144 first cooling member, 146 second hollow portion, 148 second cooling member, 149 slot, 150 first radial bearing member, 152 second radial bearing member, 154 collar, 156 third notch, 158impeller notch, 160 fourth notch, X axis of rotation, CA central axis of opening, CCP common centre point, BP base point, BC base circle, EP end point, EC end circle, G clearance, SL line.

Claims

1. A blood pump (10), in particular an intravascular blood pump, comprising: a pump housing (12) having a blood flow inlet (14) and a blood flow outlet (16) connected by a passageway (18); an impeller (20) disposed within the pump housing (12); a drive unit (26) configured to drive the impeller (20); a bearing device (40, 42) for rotatably supporting the impeller (20); Equipped with The blood pump (10) is characterized in that the bearing arrangement (40, 42) comprises at least one pivot bearing (40).

2. 2. A blood pump (10) according to claim 1, The pivot bearing (40) comprises a first pivot bearing member (118) and a second pivot bearing member (120), the first pivot bearing member (118) being pivotable relative to the second pivot bearing member (120); The first pivot bearing member (118) comprises a first abutment portion (122), and the second pivot bearing member (120) comprises a second abutment portion (132); A blood pump (10), characterized in that the first abutment portion (122) of the first pivot bearing member (118) at least partially contacts the second abutment portion (132) of the second pivot bearing member (120).

3. A blood pump (10) according to claim 2, the first abutment portion (122) of the first pivot bearing member (118) comprises a spherical portion (124), and the second abutment portion (132) of the second pivot bearing member (120) comprises a first spherical cap (134); The spherical portion (124) abuts against the first spherical cap (134); The spherical portion (124) preferably has a first radius and the first spherical cap (134) preferably has a second radius; The blood pump (10) is characterized in that the second radius is preferably greater than the first radius.

4. A blood pump (10) according to claim 3, comprising: the first pivot bearing member (118) comprises a support element (128) and a ball (126), the ball (126) abutting the support element (128) and comprising the spherical portion (124); The blood pump (10) is characterized in that the support element (128) preferably comprises a second spherical cap (136) having a third radius, the ball (126) preferably abuts the second spherical cap (136), and the third radius is preferably greater than the first radius.

5. A blood pump (10) according to claim 4, The blood pump (10) is characterized in that the ball (126) is fixed to the support element (128).

6. A blood pump (10) according to any one of claims 2 to 5, The blood pump (10) is characterized in that the first abutment portion (122) of the first pivot bearing member (118) has at least one first notch (138), preferably a plurality of first notches (138) evenly distributed along the circumference of the first abutment portion (122).

7. A blood pump (10) according to any one of claims 2 to 6, The blood pump (10) is characterized in that the second abutment portion (132) of the second pivot bearing member (120) has at least one second notch (140), preferably a plurality of second notches (140) evenly distributed along the circumference of the second abutment portion (132).

8. A blood pump (10) according to claim 7, A blood pump (10) characterized in that an axial extension of the at least one second notch (140) is non-parallel to a main axis of the second pivot bearing member (120) or the axial extension of the at least one second notch (140) is parallel to the main axis of the second pivot bearing member (120).

9. A blood pump (10) according to claim 1 or 2, the first pivot bearing member (118) comprises a slot (149) extending from the first abutment portion (122); and / or said slot (149) divides said first abutment portion (122) of said first pivot bearing member (118) into two portions; and / or The slot (149) is configured such that rotation of the first pivot bearing member (118) produces a pumping action from one side of the slot to the other side of the slot.

10. A blood pump (10) according to any one of claims 1, 2 or 9, comprising: the first abutment portion (122) of the first pivot bearing member (118) comprises a first spherical cap (134); The blood pump (10) is characterized in that the second abutment portion (132) of the second pivot bearing member (120) comprises a first spherical portion (124).

11. A blood pump (10) according to any one of claims 2 to 10, the impeller (20) has a bearing receptacle (44) therein and at least one opening (58) connecting the passage (18) with the bearing receptacle (44), the pivot bearing (40) being at least partially disposed within the bearing support (44), and / or The blood pump (10) is characterized in that the opening (58) has a central axis (CA) facing toward the second abutment portion (132) of the second pivot bearing member (120) or toward the slot (149) of the first pivot bearing member (118).

12. A blood pump (10) according to claim 11, The blood pump (10) is characterized in that the impeller (20) comprises a body (56) and at least one primary blade (54) helically protruding from an outer circumferential surface of the body (56), the opening (58) comprises an inlet (60) provided on the outer circumferential surface of the body (56), and at least a portion of the at least one primary blade (54) is disposed in contact with the inlet (60) in the circumferential direction of the body (56).

13. A blood pump (10) according to any one of claims 2 to 12, A blood pump (10), characterized in that the first pivot bearing member (118) is attached to the impeller (20) and the second pivot bearing member (120) is attached to the pump housing (12).

14. A blood pump (10) according to any one of claims 1 to 13, The bearing arrangement (40, 42) further comprises at least one radial bearing (42), the pivot bearing (40) rotatably supporting the impeller (20) relative to the pump housing (12) at one point on the impeller (20) and the radial bearing (42) rotatably supporting the impeller (20) relative to the pump housing (12) at another point on the impeller (20); the drive unit (26) being a non-contact electromagnetic drive unit configured to rotatably drive the impeller (20) relative to the pump housing (12); The blood pump (10) wherein the drive unit (26) further establishes a gravitational force on the impeller (20).

15. A blood pump (10) according to claim 14, comprising: The radial bearing (42) comprises a first radial bearing member (150) and a second radial bearing member (152); The first radial bearing member (150) is attached to the impeller (20), and the second radial bearing member (152) is attached to the pump housing (12); The first radial bearing member (150) includes a collar (154); the collar (154) extends at least partially circumferentially from an outer circumferential surface of the first radial bearing member (150); The blood pump (10) is characterized in that the collar (154) is disposed adjacent to the second radial bearing member (152), and a gap (G) is formed in the axial direction between the collar (154) and the second radial bearing member (152).

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