AXIAL BEARING AND RETAINER

Abstract

A thrust bearing configured to support axial loads that act on a rotating body includes a thrust shaft rotatably supportable in a bearing housing, a thrust collar, and a retainer connected to the thrust shaft and configured to support a plurality of thrust pieces. The thrust pieces each have a front sliding surface in sliding contact with the thrust collar, and the retainer includes a disk having a central opening and an outer circumference and a plurality of radial incisions extending radially inwardly from the outer circumference which incisions have inner ends radially spaced from the central opening. The radial incisions define circumferentially adjacent spring sections each of the which is individually axially flexible against and away from the bearing housing to open and close a spring gap between each of the spring sections and the bearing housing.

Claims

1. A thrust bearing configured to support axial loads that act on a rotating body, includes a thrust shaft rotatably supported in a bearing housing, the thrust shaft being couplable with the rotating body and having at least one thrust collar including a plurality of thrust pieces that each have a front sliding surface for sliding contact with the at least one thrust collar the plurality of thrust pieces forming two thrust-piece ring assemblies disposed on both sides of the thrust collar the thrust bearing including two retainers for retaining the respective thrust-piece ring assemblies wherein the two retainers each have a positioning section for stationary positioning and a spring-ring section configured to axially elastically deform in the event of exceeding a load limit acting on at least one of the thrust pieces, wherein a spring gap is formed between the spring-ring sections and respectively a rear-side housing section and wherein with respect to a longitudinal axis of the thrust shaft the spring-ring sections are radially outwardly disposed and the positioning sections are radially inwardly disposed and/or the spring-ring sections include a plurality of spring-ring segments lying adjacent to one another in the circumferential direction, wherein radial incisions in the spring ring sections form the spring-ring segments.

2. (canceled)

3. The thrust bearing according to claim 1, wherein the plurality of spring-ring segments have different thicknesses and/or the incisions have different lengths.

4. The thrust bearing according to claim 1, wherein each spring-ring segment is configured to retain a thrust piece.

5. The thrust bearing according to claim 1, wherein the rear-side housing segments each form an axial limit for the spring-ring sections.

6. The thrust bearing according to claim 1, wherein the thrust pieces are inserted rear-side in a spring-ring side end groove via pins and are secured in the spring-ring side end groove against self-rotating.

7. The thrust bearing according to claim 1, wherein at least one thrust piece has a fixing element for locking with the thrust collar.

8. The thrust bearing according to claim 6, wherein the end groove has a radial opening for receiving the thrust piece.

9. The thrust bearing according to claim 1, wherein the positioning sections are each a rear-side hub-type projection that extends into an axial recess of the bearing housing.

10. The thrust bearing according to claim 1, wherein the retainers are divided at least in two ring arcs.

11. A retainer for retaining a plurality of thrust pieces (8) in a thrust bearing, the retainer including a positioning section for stationary positioning in the thrust bearing and a spring-ring section for axial-elastic deforming in the event of exceeding a load limit acting on at least some of the plurality of the thrust pieces, wherein with respect to a longitudinal axis of the thrust shaft the spring-ring sections are radially outwardly disposed and the positioning sections are radially inwardly disposed and/or the spring-ring sections include a plurality of spring-ring segments lying adjacent to one another in the circumferential direction, wherein radial incisions in the spring ring sections form the spring-ring segments.

12. The thrust bearing according to claim 1, wherein the plurality of spring-ring segments have different thicknesses and/or the incisions have different lengths, wherein each spring-ring segment is configured to retain a thrust piece, wherein the rear-side housing segments each form an axial limit for the spring-ring sections, wherein the thrust pieces are configured to be inserted in a spring-ring side end groove via pins and are secured in the spring-ring side end groove against self-rotating, wherein at least one thrust piece has a fixing element for locking with the thrust collar, wherein the end groove has a radial opening for receiving the thrust piece, wherein the positioning sections are each a rear-side hub-type projection that extends into an axial recess of the bearing housing, and wherein the retainers are divided at least in two ring arcs.

13. A thrust bearing configured to support axial loads that act on a rotating body and comprising: a thrust shaft rotatably supportable in a bearing housing, the thrust shaft being couplable with the rotating body; a thrust collar; a retainer connected to the thrust shaft and configured to support a plurality of thrust pieces; the plurality of thrust pieces each having a front sliding surface in sliding contact with the thrust collar; and the retainer comprising a disk having a central opening and an outer circumference and a plurality of radial incisions extending radially inwardly from the outer circumference and having inner ends radially spaced from the central opening, the radial incisions defining circumferentially adjacent spring sections, each of the spring sections being individually axially flexible against and away from the bearing housing to individually open and close a spring gap between each of the spring sections and the bearing housing.

14. The thrust bearing according to claim 13, wherein each of the spring sections supports a single one of the plurality of thrust pieces.

15. The thrust bearing according to claim 14, wherein a length of a first one of the radial incisions is different than a length of a second one of the radial incisions.

16. The thrust bearing according to claim 15, wherein the retainer includes an axially facing circumferential groove, wherein each of the thrust pieces includes an axial projection, and wherein the axial projections are slidably mounted in the circumferential groove.

17. The thrust bearing according to claim 16, wherein each of the thrust pieces is fixed against rotation relative to the retainer.

Description

[0021] In the following a preferred exemplary embodiment of the invention is explained in more detail with reference to schematic depictions.

[0022] FIG. 1 shows a perspective depiction of a region of a thrust-piece ring assembly of an inventive thrust bearing,

[0023] FIG. 2 shows a longitudinal section through the inventive thrust bearing in the region of the thrust-piece ring assembly, and

[0024] FIG. 3 shows a detail view of a thrust-piece ring assembly shown in FIGS. 1 and 2.

[0025] According to FIG. 1, for supporting an axial load acing on a rotating body an inventive thrust bearing 1 has a thrust shaft 2 for coupling with the rotating body. The rotating body is not shown here. Likewise a bearing housing is not shown wherein the thrust shaft 2 is rotatably supported about its longitudinal axis 3.

[0026] The thrust bearing 1 is, for example, a propeller shaft of a ship and supports thrust forces of a propeller. The thrust shaft 2 is coupled end-side and aligned with the propeller shaft and a drive shaft. Turbines, blowers, cutter dredgers, and, for example, centrifugal pumps are other applications. The thrust shaft 2 has a thrust collar 4 connected such that it rotates together with the thrust shaft 2 or is formed one-piece therewith and two thrust-piece ring assemblies 6 disposed on both sides of the thrust collar 4, of which thrust-piece ring assemblies 6 for reasons of clarity only the left thrust-piece ring assembly 6 according to the depictions in FIG. 1 is depicted.

[0027] The left thrust-piece ring assembly 6 shown here will be explained below. The right thrust-piece ring assembly not shown is identically configured, with the result that what is stated below also describes the right thrust-piece ring assembly.

[0028] The thrust-piece ring assembly 6 has a plurality of thrust pieces 8 and a ring-type retainer 10 for retaining the thrust pieces 8. The retainer 10 itself has a spring-ring section or a spring ring 12 radially external with respect to the longitudinal axis 3 of the thrust shaft 2 and a radially internal positioning section or a hub 14. The thrust pieces 8 are disposed adjacent to one another in the circumferential direction of the retainer 12 and, in the region of the spring ring 12, disposed between the retainer 10 and the thrust collar 4.

[0029] According to the depiction in FIG. 2, the thrust pieces 8 each have a plate-shaped body 16 that includes a front sliding surface 18 sliding along the thrust collar 4. In addition, the thrust pieces 8 each have pins 20 for positioning on the retainer 10, which pins 20 extend rear-side and centrally therefrom.

[0030] For retaining the thrust pieces 8 or for receiving the pins 20 the retainer 10 has an end groove 22 in its spring rings 12, the axial extension or depth of which end groove 22 is set such that the pins 20 abut end-side on the end-groove base 24 and the plate-shaped bodies 16 are spaced here with their rear side 26 from a front surface 28 of the retainer 10, which front surface 28 receives the end groove 22. The end groove 22 of the retainer forms a ring and has a rectangular cross-section (see also FIG. 3). It is open via a not-shown radial opening to the outer circumference 30 of the spring ring 12 or of the retainer 10. The radial opening is such that the thrust pieces 8 can be threaded into it with their pins 20 and fed to the end groove 22.

[0031] Preferably the plate-shaped bodies 16 and the pins have a circular cross-section, wherein a plate-body diameter is selected such that in the inserted state the thrust pieces 8 contact laterally (see also FIG. 3). A pin diameter is preferably such that the thrust pieces can perform slight movements in the radial direction as they are guided in a clearance-restricted manner in the end groove 22. The clearance facilitates, among other things, the introducing of the thrust pieces 8 into the end groove 22.

[0032] The thrust pieces 8 have not-shown rotation locks, for example, parallel pins disposed with respect to the pins 20, using which a self-rotation about its axial axis 29 is prevented. The thrust piece 8 last installed or last introduced into the end groove 22 also has a not-shown fixing element for fixing the thrust pieces 8 in the end groove 22 in order to prevent a displacing of the thrust pieces 8 inside the end groove 22. This rotation lock can also consist of a pin or pin-type element that engages in a corresponding securing groove of the respective retainer 10 or locks therewith in an interference-fit manner.

[0033] The positioning section 14 is configured as a rear-side hub that immerses into a radially inner axial recess 31 of a section 32 of the bearing housing. An axial extension or depth of the recess 31 is such that the positioning section or the hub 14 abuts end-side on the recess base 33 and an axial spring gap 38 is thereby formed between a rear side 34 of the spring ring 12 and an opposing housing-ring surface 36. Preferably as indicated by the dashed line the retainer 10 is screwed to the housing section 32 in the region of the positioning section 14. In order to prevent that a lubricating oil located in the bearing housing penetrates to the recess base 33, a seal ring 40 is inserted in the outer circumferential groove of the hub 14, which seal ring 40 sealingly abuts on an opposing inner circumferential surface 42 of the housing section 32.

[0034] The spring gap 38 is an axial ring gap and expanded in this exemplary embodiment radially from inward to outward in a wedge-shaped manner or open radially from inward to outward.

[0035] As shown in FIG. 3 the spring ring has a plurality of radial incisions 44 that extend radially from inward to outward. For reasons of clarity only one incision 44 is quantified representatively for all incisions in the retainer 10.

[0036] The incisions 44 are radially inwardly closed, and open to the outer circumference 30 of the spring ring 12. Each incision 44 has a radially inwardly lying base 48 that is located with the remaining incision bases 48 on a virtual circle that is located in the transition region from the positioning sections 14 onto the spring rings 12 (see also FIG. 2). To avoid notch effects the incision bases 48 are rounded. In this exemplary embodiment a plurality of identically large spring ring segments 50 are formed by the incisions 44, which spring-ring segments 50 each preferably receive a thrust piece 8. For reasons of clarity only one spring ring segment 50 is quantified representatively for all spring ring segments of the retainer 10. In the event of exceeding a load limit acting on at least a plurality of the thrust pieces 8 the respective spring-ring segment 50 performs an axial-elastic deformation, whereby an equalizing is effected of an axial load distribution acting on the thrust shaft 2.

[0037] For simplification of assembly the retainer shown here is divided in at least two ring arcs 52, 54. The ring arcs 52, 54 here are two ring halves that each span 180°. To align the ring halves in the assembled state they can include not-shown corresponding circumferential-side centering elements in the region of their separation plane 56 or their separation surfaces.

[0038] In operation the thrust shaft 2 is set into rotation, whereas the thrust-piece ring assemblies 6 is supported in the bearing housing in a stationary manner. The thrust collar 4 slides along the sliding surfaces 18 of the thrust pieces 8, wherein with its rotational movement it respectively at least sectionally immerses in an oil bath located in the bearing housing 32. A lubricant film thereby respectively forms on the sliding surfaces 18, with the result that a friction between the thrust collar 4 and the thrust pieces 8 is minimized and the sliding surfaces 18 are also cooled. In the normally loaded state or with coaxial orientation of the longitudinal axis 3 of the thrust shaft 2 with respect to the bearing housing axis the spring ring segments 50 are in the same or in essentially the same orientation.

[0039] However, as soon as an axial load is unequally distributed on the thrust pieces 8 due to an angular difference between the axes, in the event of the exceeding of a load limit an axial-elastic deforming of the spring rings 12 or their spring-ring segments 50 is established. The highly loaded thrust pieces 8 transmit larger axial forces, which thrust pieces 8 thereupon realize a greater spring travel in the axial direction corresponding to their spring characteristic curve. Correspondingly smaller spring travels are realized by lightly loaded thrust pieces 8. These different load-dependent deformations of the spring-ring segments 50 effect a more even load distribution of the axial load on a plurality of thrust pieces 8. A spring characteristic curve of the spring ring segments 50 is also configured such that the forming of the lubricant film is ensured.

[0040] A maximum axial-elastic deforming of the spring-ring segments 50 is limited here by a rear-side running-into the respective opposing housing-ring surface 36 by its rear side 34, so that plastic deformations of the spring-ring segments 50 and thus damage to the retainers 10 is prevented. Due to different configuration of the individual spring-ring segments 50, for example, due to different thicknesses or lengths of the incisions 44, each spring-ring segment 50 can be given an individual spring characteristic value, and the load distribution can thus be adapted to, for example, shaft bend lines and the like. Alternatively and/or additionally the resilience of the spring-ring segments 50 can be adapted to, for example, the shaft bend lines by different spring gap widths between the spring ring segments 50 and the housing ring surface 36.

[0041] Disclosed is a thrust bearing for the supporting of axial loads that act on a rotating body, wherein the thrust bearing includes ring receptacles for the receiving of thrust pieces that each have a positioning section for stationary positioning and a spring-ring section for axial-elastic deforming in the event of exceeding of a load limit acting on at least a plurality of the thrust pieces, wherein a spring gap is formed between the spring-ring sections and respectively one rear-side housing section, as well as a retainer for such a thrust bearing.

REFERENCE NUMBER LIST

[0042] 1 Thrust bearing

[0043] 2 Thrust shaft

[0044] 3 Longitudinal axis

[0045] 4 Thrust collar

[0046] 6 Thrust-piece ring assembly

[0047] 8 Thrust piece

[0048] 10 Retainer

[0049] 12 Spring-ring section/spring ring

[0050] 16 Plate-shaped body

[0051] 18 Sliding surface

[0052] 20 Pin

[0053] 22 End groove

[0054] 24 End-groove base

[0055] 26 Rear side

[0056] 28 Front surface

[0057] 29 Axial axis

[0058] 30 Outer circumference

[0059] 31 Axial recess

[0060] 32 Section/Housing section

[0061] 33 Recess base

[0062] 34 Rear side

[0063] 36 Housing-ring surface

[0064] 38 Spring gap/Axial gap

[0065] 39 Line

[0066] 40 Seal ring

[0067] 42 Inner circumferential surface

[0068] 44 Incision

[0069] 48 Base

[0070] 50 Spring-ring segment

[0071] 52 Ring arc

[0072] 54 Ring arc

[0073] 56 Separation plane