CENTRIFUGAL PUMP

Description

Technical field

[0001] The invention relates to a centrifugal pump with a motor comprising a housing and a rotor shaft arranged therein, with a drive side and an opposite non-drive side, and a drive bearing assigned to the drive side for rotatably supporting the rotor shaft, a drive side bearing receptacle provided between the drive bearing and the housing, and a non-drive bearing assigned to the non-drive side for rotatably supporting the rotor shaft, a non-drive side bearing receptacle provided between the non-drive bearing and the housing. Background of the invention

[0002] Centrifugal pumps are known from the prior art and are used to pump a fluid by means of the rotary motion of an impeller located within the pump. The impeller is driven by a motor of the centrifugal pump via a rotor shaft. Highly rotating rotor shafts, in particular, require a high degree of balancing to ensure minimal vibration of the motor, including the rotor shaft and impeller. However, achieving such a high degree of balancing is only possible with considerable effort and expense in manufacturing.

[0003] For this reason, a frequently chosen option is the 'soft' mounting of the rotor shaft, which compensates for any potential imbalance of the rotor shaft at high speeds. The rotor shaft mounting must be able to absorb and dampen radial and axial vibrations. However, due to clearance dimensions, axial and radial deflection of the rotor shaft must be limited despite such a soft mounting. Furthermore, the soft mounting should occupy as little installation space as possible.

[0004] US 2004 / 134708 A1 describes an electro-hydraulic power steering device comprising a motor having a rotating shaft and provided with a bearing for rotatably supporting the rotating shaft, a hydraulic pump arranged at one end of the rotating shaft of the motor and driven by the motor, a first elastic body for supporting the bearing, and a second elastic body for pressing the bearing in an axial direction.

[0005] EP 0 520 303 A2 describes a plain bearing with an elastic shell for the motor shaft of a wet-running motor of a centrifugal pump, wherein the shell of the plain bearing is provided at least at one end with a radial additional wall having a through-hole for the motor shaft and the additional wall is designed in the edge region of its through-hole as a contact seal for the motor shaft.

[0006] The solutions known from the prior art, using two O-rings for radial bearing and two square rings for axial bearing, are not only complex and therefore expensive to manufacture, but have also proven to be unreliable in the long term and require a great deal of maintenance. Description of the invention

[0007] Starting from this situation, it is an object of the present invention to provide a centrifugal pump whose motor shaft is mounted in a manufacturing-technically simple manner with reduced vibration, wherein the reduced vibration mounting can be manufactured cost-effectively.

[0008] The object of the invention is achieved by the features of the independent claim. Advantageous embodiments are specified in the dependent claims.

[0009] Accordingly, the task is solved by a centrifugal pump with a motor comprising a housing and a rotor shaft arranged therein, the latter having a drive side and an opposite non-drive side, and a drive bearing assigned to the drive side for rotatably supporting the rotor shaft, a drive side bearing receptacle provided radially between the drive bearing and the housing for thermally decoupling the rotor shaft and the housing, and a retaining ring arranged between the drive bearing and the housing, and a non-drive bearing assigned to the non-drive side for rotatably supporting the rotor shaft in the same manner, a non-drive side bearing receptacle provided radially between the non-drive bearing and the housing for thermally decoupling the rotor shaft and the housing, and a spring ring arranged between the non-drive bearing and the housing, the spring force of which acts on the rotor shaft in the direction of the drive side,wherein the drive side bearing receptacle and the non-drive side bearing receptacle have a component extending at least axially, made of a flexible, non-conductive material, and a plurality of damping elements are provided on the inside of the axially extending component, bearing against the drive bearing and the non-drive bearing, and counteracting radial movement of the rotor shaft.

[0010] A key aspect of the invention is that the damping elements counteract at least one radial movement of the rotor shaft, thereby cushioning vibrations and increasing smoothness of operation. Furthermore, vibrations in the axial direction can be reduced by means of a possible radial component of the drive-side bearing mount and / or the non-drive-side bearing mount, as described below. Simultaneously, the retaining ring and the spring ring provide axial fixation of the rotor shaft relative to the housing. Finally, thermal decoupling achieves insulation, thus reducing or even completely preventing bearing currents that typically lead to erosion and damage to the bearing raceways. The proposed solution thus enables a 'soft' mounting of the rotor shaft, which compensates for any potential imbalance of the rotor shaft, particularly at high speeds.

[0011] Compared to the complex and therefore expensive solutions known from the prior art, which use two O-rings for radial bearings and two square rings for axial bearings, the proposed solution is characterized by a significantly simpler design requiring very little installation space. It can absorb and dampen both radial and axial vibrations and is both permanently reliable and requires minimal maintenance. Compared to two O-rings and two square rings, the contact area between the bearing and the housing can be increased by a factor of 1.5 or more using the proposed damping elements. This reduces surface pressure, improves the centering of the rotor shaft, and ultimately also improves damping. A centrifugal pump is generally defined as a turbomachine that uses rotary motion and dynamic forces to pump predominantly liquids.In addition to the tangential acceleration of the fluid, also called the medium, centrifugal force occurring in radial flow is used for pumping, which is why centrifugal pumps are also referred to as centrifugal pumps. In regular operation of the centrifugal pump, the motor housing is preferably arranged above a pump housing in which an impeller, driven by the motor via the rotor shaft, is provided for pumping the fluid. The motor housing can be fixedly connected to the pump housing and / or be a single unit. Preferably, the motor shaft projects into the pump housing on the drive side of the motor housing and / or the impeller is fixedly connected to the motor shaft on the drive side. On the non-drive side, the motor shaft preferably does not extend from the housing. The fluid preferably comprises water or another liquid medium such as wastewater.The fluid can contain solids such as impurities of any kind, in particular feces, sediments, dirt, sand, or even small pieces of wood, brush, textiles, rags, or the like. Preferably, the motor housing is made of metal, in particular stainless steel, and / or the pump housing is made of plastic.

[0012] According to the invention, the drive bearing and the non-drive bearing are designed as rolling bearings in which rolling elements between an inner ring and an outer ring reduce frictional resistance and effectively fix the rotor shaft in relation to the housing. The inner ring, against which the rotor shaft preferably rests in contact, and / or the outer ring, which is preferably oriented away from the rotor shaft towards the housing, preferably have hardened steel surfaces to minimize the rolling friction of the rolling elements, for example, balls. The rolling bearing can be designed as a ball bearing, cylindrical roller bearing, needle roller bearing, tapered roller bearing, spherical roller bearing, or the like. Thermally decoupled means that, due to the drive-side bearing mount and / or the non-drive-side bearing mount, current, heat, and / or cold transfer between the motor shaft and the non-drive-side bearing is prevented.Drive bearings and / or non-drive bearings as well as the housing are reduced or prevented, in particular a creepage current.

[0013] The drive bearing receptacle and / or the non-drive bearing receptacle encompass, in particular radially, the drive bearing and / or the non-drive bearing, especially its outer ring. The drive bearing receptacle and / or the non-drive bearing receptacle is, in particular, positioned in contact between the housing and the drive bearing and / or the non-drive bearing. Preferably, the drive bearing receptacle and / or the non-drive bearing receptacle has a smaller inner diameter compared to the outer diameter of the drive bearing and / or the non-drive bearing, which is, in particular, 0.5%, 1%, 2%, or 5% smaller to achieve a so-called 'press-fit' fit. The terms axial and radial refer in particular to the rotor shaft.

[0014] The axially extending component is preferably positioned radially between the drive bearing and / or the non-drive bearing and the housing, and / or extends axially over the same or approximately the same axial extent as the drive bearing and / or the non-drive bearing. The damping elements preferably bear in contact with the outer ring and / or an outer surface of the drive bearing and / or the non-drive bearing. Furthermore, the damping elements preferably extend axially or perpendicular to the axial extent of the rotor shaft. More preferably, if the damping elements extend axially, they extend over the same, approximately the same, or at least half or half of the axial extent of the drive bearing and / or the non-drive bearing.

[0015] In a preferred embodiment, the damping elements are provided circumferentially and / or at regular intervals on the inside of the axially extending component. According to another preferred embodiment, an axially extending groove is provided between two adjacent damping elements and / or the damping elements are rib-shaped. Preferably, the groove and the damping element each have the same or approximately the same width and / or the groove has the same or approximately the same depth as the width of the damping element. The damping element can be made of a harder material than the drive-side bearing receptacle and / or the non-drive-side bearing receptacle, in particular a higher Shore hardness as described below. The side walls of the grooves can be flattened with respect to the groove valleys, for example at an angle of 15° or 20°, in particular ≤ 30° per side.The grooves can have a width of 3.1 mm, a depth of 1.5 mm, and / or an angle of between 4° and 15°, and in particular over 7.5°, per groove. The width of the grooves can also be determined by the circumference of the drive-side bearing receptacle and / or the non-drive-side bearing receptacle and the number of damping elements, which can vary, for example, between 24 and 90 depending on the bearing size. The depth of the grooves can depend on the width of the damping elements, the hardness of the material of the damping elements, and the resulting compression set resistance and damping behavior. Furthermore, the depth can be 30 to 60% of the width. The drive-side bearing receptacle and / or non-drive-side bearing receptacle can have an outer diameter of 70 mm, 84 mm, or 90 mm and an inner diameter of 60 mm, 71 mm, or 80 mm, and / or a width of 20 mm, 25 mm, or 30 mm.In principle, the dimensions of the drive-side bearing housing and / or the non-drive-side bearing housing, in particular the inner and outer diameters and width, can vary depending on the specific bearing selected. The width can vary between the bearing width and the axial thickness of the drive-side bearing housing and / or the non-drive-side bearing housing plus the thickness of the retaining ring and, if applicable, the spring washer, especially taking into account the required electrical clearances and creepage distances; for example, bearing width B multiplied by a factor of 1.15 to 2.0. The damping elements and / or grooves can extend over 15 mm, 21 mm, or 25 mm.

[0016] If a damping element-free area means that no grooves are provided in this area and / or the drive bearing and / or the non-drive bearing does not abut the drive side bearing receptacle and / or the non-drive side bearing receptacle, then, according to a further preferred embodiment, the drive bearing and / or the non-drive bearing can partially rest on such a damping element-free area. The damping element-free area can extend over 2 mm, 3 mm, 4 mm, or 5 mm, or over the width of the drive bearing and / or the non-drive bearing multiplied by a factor of 0.15 to 0.3. The drive side bearing receptacle and / or the non-drive side bearing receptacle is preferably flat on the outside, and in particular, completely flat. The damping element-free area can be formed integrally with a radially extending component described below.

[0017] According to another preferred embodiment, the damping elements are designed as ramps at the end of the drive-side bearing receptacle opposite the drive side and / or at the end of the non-drive-side bearing receptacle opposite the non-drive side. This ramp design facilitates the insertion of the drive-side bearing and / or the non-drive-side bearing into the drive-side bearing receptacle and / or the non-drive-side bearing receptacle. The ramp, particularly designed as a chamfer, preferably extends axially over 4 mm, 5 mm, or 6 mm, or over a factor of 0.1 to 0.4 times the width of the damping element, and / or is flattened by 10° to 30° with respect to the axial plane.

[0018] In a further preferred embodiment, the drive side bearing receptacle and / or the non-drive side bearing receptacle has a radial component extending radially inward from the axially extending component and counteracting axial movement of the rotor shaft. This radial component is formed integrally with the axially extending component from the flexible material. The radially inward-extending component is preferably located between the drive side bearing receptacle and / or the non-drive side bearing receptacle and the housing. The radially inward-extending component preferably extends over 3 mm, 3.5 mm, 4 mm, or 5 mm and / or is disk-shaped in axial side view, and / or is oriented according to the outer and inner diameters of the respective drive side bearing receptacle and / or non-drive side bearing receptacle.

[0019] According to another preferred embodiment, the radially extending component is arranged at the drive-side end of the drive-side bearing receptacle and / or at the non-drive-side end of the non-drive-side bearing receptacle and / or rests axially against the housing. The radially extending component allows the rotor shaft to be axially fixed to the housing and / or damped in the axial direction.

[0020] According to the invention, the centrifugal pump has a retaining ring, wherein the retaining ring is preferably made of metal and / or is annular in shape and / or is provided at the end of the drive bearing receptacle opposite the drive side. The retaining ring preferably has a material thickness of 1 mm, 2 mm or 3 mm and / or is in the form of a disc and / or disc-like, or designed according to DIN 472. Preferably, the retaining ring is provided axially between the drive bearing and the housing at the end of the drive bearing receptacle opposite the drive side, wherein the drive bearing is preferably fixed axially, and in particular contacting, on the drive side via the drive bearing receptacle on one side to the housing and on the end of the drive bearing receptacle opposite the drive side to the housing via the retaining ring on the other side, in particular clamped.Accordingly, the retaining ring allows for simple axial fixation of the drive bearing and thus of the motor shaft in relation to the housing.

[0021] According to the invention, the centrifugal pump includes a spring ring, wherein the spring ring is preferably made of spring metal and / or is ring-shaped and / or is provided at the end of the non-drive side bearing receptacle facing the non-drive side. The spring ring preferably has a material thickness of 1 mm, 2 mm, 3 mm or 5 mm and / or is in the form of a disc and / or disc-like, and / or is designed as a spring washer for the axial adjustment of ball bearings according to DIN 42013.Preferably, the spring ring is positioned axially between the non-drive bearing and the non-drive side bearing receptacle, wherein the non-drive bearing is preferably fixed axially, and in particular contacting, on one side at the end of the non-drive side bearing receptacle opposite the non-drive side to the housing, and on the other side by means of a spring ring on the non-drive side to the housing, in particular clamped, so that the spring force acts on the non-drive bearing away from the non-drive side. Accordingly, the spring ring allows for simple axial fixation of the non-drive bearing and thus of the motor shaft with respect to the housing.

[0022] According to a further preferred embodiment, the flexible material comprises ethylene propylene diene monomer rubber and / or rubber and / or has a hardness of ≥ 60 Shore and ≤ 100 Shore or 80 Shore. Ethylene propylene diene monomer rubbers, abbreviated EPDM, ethylene propylene diene; M group, are terpolymers of ethylene, propylene, and an unspecified diene. EPDM is classified as a saturated-chain synthetic rubber, specifically as an M group according to DIN ISO 1629. Commercially available EPDM rubbers have an ethylene content of 45–75% by weight. EPDM is resistant to long-term aging, UV radiation, and ozone, weathering, robust, walkable, thermally resistant, and frost-proof. Alternatively, the flexible material can include an elastomer, for example an elastomeric plastic, a thermoplastic plastic or a thermosetting plastic, or NBR, HNBR, XNBR, VMQ, PTFE, AU, FKM, FFPM (FFKM) - perfluoroelastomers.Shore hardness generally represents a material property for elastomers and plastics and is determined in particular as specified in the standards DIN EN ISO 868, DIN ISO 7619-1 and ASTM D2240-00. Brief description of the drawings

[0023] The invention is explained in more detail below with reference to the accompanying drawings and by way of preferred embodiments.

[0024] The drawings show Fig. 1 shows a motor of a centrifugal pump in a schematic sectional view according to a preferred embodiment of the invention, Fig. 2 shows a drive side bearing mount of the motor made of Fig. 1in three detailed views, top left perspective towards a drive-side end of a rotor shaft of the motor, top right perspective from the drive-side end of the rotor shaft towards a housing of the motor and bottom in partial section with left towards the drive-side end of the rotor shaft according to the preferred embodiment of the invention, Fig. 3 a non-drive side bearing mount of the motor made of Fig. 1 in three detailed views, top left perspective view towards the non-drive end of the rotor shaft, top right perspective view from the non-drive end of the rotor shaft towards the housing and bottom partial section view with left towards the non-drive end of the rotor shaft according to the preferred embodiment of the invention, and Fig. 4 in the Fig. 4a a drive bearing of the engine made of Fig. 1 in a detailed view and in the Fig. 4b . a non-drive side bearing of the engine made of Fig. 1in a detailed view according to the preferred embodiment of the invention. Detailed description of the implementation examples

[0025] Fig. 1 Figure 1 shows a motor 1 of a centrifugal pump 2 in a schematic sectional view according to a preferred embodiment of the invention. The motor 1 has a housing 3 and a rotor shaft 4 arranged in the housing 3 for driving an impeller (not shown) of the centrifugal pump 2 at a drive side 5 of the rotor shaft 4. Opposite the drive side 5, the rotor shaft 4 has a non-drive side 6.

[0026] Furthermore, the motor 1 has a drive bearing 7 arranged on the drive side 5, by means of which the rotor shaft 4 is rotatably mounted on the housing 3 on the drive side 5. Similarly, a non-drive bearing 8 is provided on the non-drive side 6, by means of which the rotor shaft 4 is rotatably mounted on the housing 3 on the non-drive side 6. The drive bearing 7 and the non-drive bearing 8 are designed as rolling bearings, namely as deep groove ball bearings.

[0027] Radially and axially between the drive bearing 7 and the housing 3, a drive side bearing receptacle 9 is provided facing the drive-side end of the rotor shaft 4, through which the rotor shaft 4 and the housing 3 are thermally decoupled. The drive side bearing receptacle 9 is shown in detail in Fig. 2The upper left view is in perspective towards the drive-side end of the rotor shaft 4, the upper right view is in perspective from the drive-side end of the rotor shaft 4 towards the housing 3, and the lower view is in partial section looking left towards the drive-side end of the rotor shaft 4. Furthermore, an annular retaining ring 10 made of metal is provided between the drive bearing 7 on the side of the drive bearing 7 facing away from the drive-side end of the rotor shaft 4 and the housing 3. This retaining ring extends only radially, but not axially, with respect to the rotor shaft 4.

[0028] The drive side bearing receptacle 9 shows, as detailed below Fig. 2 It can be seen that an axially extending component 11 and a radially extending component 12 are present, arranged at right angles to each other and receiving the drive bearing 7 in contact on their inner sides. As can be seen from Figs. 1 and Fig. 4aAs can be seen, the axial component 11 extends essentially over the entire axial extent of the drive bearing 7, while the radial component 12 extends only over a portion of the radial extent of the drive bearing 7 from the outer edge of the drive bearing 7 towards the motor shaft 4. In this way, the drive bearing 7 is held in radial and axial contact with the housing 3 on the drive side 5, as also shown in Fig. 4a shown.

[0029] Furthermore, a non-drive side bearing receptacle 13 is provided radially and axially between the non-drive bearing 8 and the housing 3, facing the non-drive end of the rotor shaft 4, through which the rotor shaft 4 and the housing 3 are thermally decoupled. The non-drive side bearing receptacle 13 is shown in detail in Fig. 3, top left perspective towards the non-drive end of the rotor shaft 4, top right perspective towards the non-drive end of the rotor shaft 4 towards the housing 3 and bottom in partial section with left towards the non-drive end of the rotor shaft 4.

[0030] Furthermore, an annular spring ring 14 made of spring metal is provided between the non-drive bearing 8 on the side of the drive bearing 7 facing the non-drive end of the rotor shaft 4 and the housing 3. This spring ring extends only radially, but not axially, with respect to the rotor shaft 4. The spring force of the spring ring 14 acts on the rotor shaft 4 in the direction of the drive side 5. Since the rotor shaft 4 bears axially against both the drive bearing 7 and the non-drive bearing 8 on both the drive side 5 and the non-drive side 6, the rotor shaft 4 is axially fixed in the housing 3 by the spring ring 14.

[0031] The non-drive side bearing receptacle 13 shows, as detailed below Fig. 3 As can be seen, the drive side bearing receptacle 9 has an axially extending component 15 and a radially extending component 16, which are arranged at right angles to each other and whose inner surfaces contact the non-drive bearing 8. Figs. 1 and 4bAs can be seen, the axial component 15 extends substantially over the entire axial extent of the non-drive bearing 8, while the radial component 16 extends only over a portion of the radial extent of the non-drive bearing 8 from the outer edge of the non-drive bearing 8 towards the motor shaft 4. In this way, the non-drive bearing 8 is held in radial and axial contact with the housing 3 on the outside of the non-drive side 6. The spring ring 14 is positioned between the non-drive bearing 8 and the housing 3, between the radial component 16 of the non-drive side bearing receptacle 13 and the side of the non-drive bearing 8 facing the non-drive side 6.

[0032] The axially extending components 11, 15 of the drive side bearing receptacle 9 and the non-drive side bearing receptacle 13 have on their inner surfaces a plurality of damping elements 17 which are in contact with the drive bearing 7 and the non-drive bearing 8, respectively, and which counteract radial movement of the rotor shaft 4. The damping elements 17 are provided circumferentially at regular intervals on the inner surface of the axially extending component 11, 15, with a groove 18 provided between each pair of adjacent damping elements 17, so that the damping elements 17 have a rib-like design. While in Fig. 2 where the damping elements 17 and thus also the grooves 18 of the drive side bearing receptacle 9 extend in a radial direction, are in Fig. 3 Damping elements 17 and grooves 18 of the non-drive side bearing receptacle 13 are shown, extending in the axial direction.

[0033] The drive-side bearing receptacle 9 is designed without damping elements on the drive side 5, and the non-drive-side bearing receptacle 13 is designed without damping elements on the non-drive side 6, i.e., without grooves 18 or the like. Furthermore, the drive-side bearing receptacle 9 and the non-drive-side bearing receptacle 13 are circular and hollow cylindrical with a flat, axially extending outer surface, without any recesses or the like on the radial outer surface.

[0034] To facilitate the insertion of the drive bearing 7 into the drive side bearing receptacle 9 and the non-drive bearing 8 into the non-drive side bearing receptacle 13, the damping elements 17 at the end of the drive side bearing receptacle 9 opposite the drive side 5 (not shown) and at the end of the non-drive side bearing receptacle 13 opposite the non-drive side 6 are provided with ramps 19. The drive side bearing receptacle 9 and the non-drive side bearing receptacle 13, as well as their axial and radial components 11, 12, 15, 16, are made of a flexible, non-conductive material, namely ethylene propylene diene monomer rubber with a hardness of 80 Shore A.

[0035] The described embodiments are merely examples that can be modified and / or supplemented in various ways within the scope of the claims. As long as it falls within the scope of the claims, any feature described for a particular embodiment can be used independently or in combination with other features in any other embodiment. As long as it falls within the scope of the claims, any feature described for an embodiment of a particular category can also be used accordingly in an embodiment of a different category. Reference symbol list

[0036] Motor 1 centrifugal pump 2 Housing 3 Rotor shaft 4 drive side 5 Non-drive side 6 drive bearing 7 Non-drive bearing 8 Drive side bearing mount 9 retaining ring 10 Axial component 11 Radial component 12 Non-drive side bearing mount 13 spring washer 14 Axial component 15 Radial component 16 Damping element 17 Nut 18 ramp 19

Claims

1. A centrifugal pump (2) comprising a motor (1) having a housing (3) and a rotor shaft (4) arranged therein with a drive side (5) and an opposite non-drive side (6), a drive bearing (7), which is associated with the drive side (5) and configured as a rolling bearing, for rotatably supporting the rotor shaft (4), a drive-side bearing mount (9), which is provided radially between the drive bearing (7) and the housing (3), for thermally decoupling the rotor shaft (4) and the housing (3), and a securing ring (10), which is disposed between the drive bearing (7) and the housing (3), and a non-drive bearing (8), which is associated with the non-drive side (6) and is configured as a rolling bearing, likewise for rotatably supporting the rotor shaft (4), a non-drive-side bearing receptacle (13), which is provided radially between the non-drive bearing (8) and the housing (3), for thermally decoupling the rotor shaft (4) and the housing (3), and a spring ring (14), which is disposed between the non-drive bearing (8) and the housing (3) and the spring force of which acts on the rotor shaft (4) in the direction of the drive side (5), wherein the drive-side bearing mount (9) and the non-drive-side bearing mount (13) has an at least axially extending component (11, 15) made of a flexible, non-conductive material, and a plurality of damping elements (17) bearing against the drive bearing (7) and against the non-drive bearing (8) and counteracting a radial movement of the rotor shaft (4) are provided internally on the axially extending component (11, 15).

2. The centrifugal pump (2) according to the preceding claim, wherein the damping elements (17) are provided circumferentially and / or at regular distances internally on the axially extending component (11, 15).

3. The centrifugal pump (2) according to any one of the preceding claims, wherein an axially extending groove (18) is provided between two adjacent damping elements (17) and / or the damping elements (17) are rib-like.

4. The centrifugal pump (2) according to any one of the preceding claims, wherein the damping elements (17) are formed in a ramp-like fashion at the end of the drive-side bearing mount (9) opposite the drive side (5) and / or at the end of the non-drive-side bearing mount (13) opposite the non-drive side (6).

5. The centrifugal pump (2) according to any one of the preceding claims, wherein the drive-side bearing mount (9) and / or the non-drive-side bearing mount (13) has a radial component (12, 16), which extends radially inwardly from the axially extending component (11, 15), counteracts an axial movement of the rotor shaft (4), and is formed in one piece with the axially extending component (11, 15) made of the flexible material.

6. The centrifugal pump (2) according to the preceding claim, wherein the radially extending component (12, 16) is disposed at the end of the drive-side bearing mount (9) facing the drive side (5) and / or at the end of the non-drive-side bearing mount (13) facing the non-drive side (6) and / or bears axially against the housing (3).

7. The centrifugal pump (2) according to any one of the preceding claims, wherein the securing ring (10) is made of metal and / or is annular and / or the securing ring (10) is provided at the end of the drive-side bearing mount (9) opposite the drive side (5).

8. The centrifugal pump (2) according to any one of the preceding claims, wherein the spring ring (14) is made of spring metal and / or is annular and / or the spring ring (14) is provided at the end of the non-drive-side bearing mount (13) facing the non-drive side (6).

9. The centrifugal pump (2) according to any one of the preceding claims, wherein the flexible material comprises ethylene-propylene-diene rubber and / or has a hardness of ≥ 60 Shore and ≤ 100 Shore or 80 Shore.