DE102020211758A1 - Bearing device for a turbomachine - Google Patents

Abstract

The invention relates to a bearing device (10) for a turbomachine, in particular for accommodating at least one roller bearing for supporting a rotor, the bearing device (1, 10) having an assembly area (2, 12) and a bearing mount (4, 14) which a transition region (6, 16) are connected to one another. The assembly area (12) has a large number of fastening openings (13) for fastening the bearing device (10).

Description

The invention relates to a bearing device for a turbomachine, in particular for accommodating at least one roller bearing for supporting a rotor, the bearing device having a mounting area and an annular bearing mount which are connected to one another by a transition area.

Bearings of turbomachines are often held by so-called squirrel cages, in which the mounting flange is connected to the bearing mount via spring bars. A ball or roller bearing, for example, is attached directly or indirectly to the bearing mount. The spring rods, which form the transition area between the mounting flange and the bearing mount, are dimensioned and designed according to the load cases that occur. The transition area must in particular prevent an offset between the mounting flange and the bearing mount in the radial direction and a tilting of the bearing mount relative to the axis. In the case of a bearing cage, the stiffness of the transition area is primarily determined by the number, the cross-sections and the length of the spring bars, with the length of the spring bars decisively influencing the stiffness. The radial displacement and tilting depend on each other via the geometry of the rods (round or square). High loads lead to stress peaks at the transitions between the rods and the bearing mount or the mounting flange. Accordingly, such a design also restricts the minimum overall length of the bearing cage and thus also of the bearing device when there is a high load. Since the length of the transition area locally defines the length of the engine, a shortening of the transition area allows the entire turbomachine to be shortened and thus a large weight saving.

Proceeding from this, it is an object of the present invention to propose an improved bearing device for a turbomachine. According to the invention, this is achieved by the teaching of the independent claim. Advantageous developments of the invention are the subject matter of the dependent claims.

In order to solve the problem, a bearing device for a turbomachine is proposed, which serves in particular to accommodate at least one roller bearing for supporting a rotor of the turbomachine. The bearing device has an assembly area and a bearing mount, which are connected to one another by a transition area. In this case, the assembly area has a plurality of assembly sections with at least one fastening opening for fastening the bearing device.

The mounting area of the bearing device has a plurality of mounting sections, by means of which the bearing device is fastened on or in the turbomachine in order to mount the rotor of the turbomachine in the turbomachine. In particular, the assembly sections are not connected in the assembly area and are therefore designed to be flexible compared to an annular assembly flange. In this way, the rigidity of the bearing device in the assembly area can be adjusted by suitably designing the assembly sections, whereas the high rigidity of a conventional design with a particularly one-piece flange ring in the assembly area can hardly or only slightly be influenced. If the assembly area is made up of a plurality of assembly sections, the housing of the turbomachine assumes the fixed positioning of the assembly area and thus of the bearing device in the turbomachine. Because each assembly section has at least one fastening opening for fastening the bearing device, each assembly section can be fastened to the turbomachine by fastening means in order to transfer holding forces resulting from the bearing of the rotor into/onto the housing of the turbomachine. Screw bolts and screw nuts arranged thereon, for example, serve as fastening means.

The proposed solution not only enables the weight of the bearing device to be reduced, it can also be made shorter, since the proposed design of the assembly area leads to improved adjustability of the rigidity of the bearing device. In particular, in connection with the design of the transition area, a defined rigidity and deflectability of the bearing device can be achieved in connection with a low tendency to tilt to optimize the length of the transition area, which in particular also makes it possible to shorten the engine.

The transition area is in particular designed to be rotationally symmetrical. The transition region has essentially the same mechanical properties in all directions radially to the axis of rotation, in particular with regard to the rigidity and the displaceability of the bearing mount.

In one embodiment of the bearing device, the fastening openings are aligned parallel to the axis of rotation of the turbomachine and are arranged on a circle running coaxially around the axis of rotation, and/or distributed uniformly in the circumferential direction of the bearing device arranged. A corresponding arrangement, distribution and orientation of the fastening openings enables a suitable and sufficient, in particular also uniform, force transmission from the bearing device to the turbomachine or its supporting components.

In one embodiment of the bearing device, the assembly sections are formed by rods that run in particular radially. On one axial side, the rods form the contact surface of the bearing device on a supporting component of the turbomachine, to which the bearing device is attached and to which the bearing device transmits the bearing forces from the bearing mount to the turbomachine. In order to produce a suitable contact for transmitting the bearing forces, the contact surfaces of the assembly sections are, for example, planar and lie in a plane arranged perpendicularly to the axis of rotation of the rotor. The fastening openings arranged on the mounting sections are in particular offset radially outwards from the transition region, which is why the mounting sections and in particular the side of the mounting sections opposite the contact surface have a design suitable for arranging fastening means. In the case of an embodiment of the assembly sections in the form of rods which extend radially with essentially the same cross section, these move away from one another along their extension and are in particular also designed to be flexible with respect to one another. Such a design enables the rigidity of the bearing device or its connection to the turbomachine to be adjusted, in particular also as a function of the radial distance between the fastening means and the axis of rotation.

In one embodiment of the bearing device, at least one section of the transition area is designed as a hollow-cylindrical wall. The structure of the wall can be closed or have one or more recesses. The wall can also have at least two different wall thicknesses. A hollow-cylindrical wall section can be designed with a high structural strength, which counteracts tilting of the bearing mount relative to the mounting area. With a suitable structure of the wall, axial movements between the bearing seat and the assembly area are permitted to a small extent, with the result that the transition area can be designed with a certain elasticity in the axial direction. In the context of the invention, the term "hollow-cylindrical" also includes designs of the wall or wall sections that do not have an exact hollow cylindrical shape, such as designs that are not exactly rotationally symmetrical, or walls with varying wall thicknesses or, for example, walls whose cross-section varies in at least one area are tapered or enlarged and therefore, in particular in sections, are in the form of a hollow cone, bulbous or the like.

In one embodiment of the bearing device, the transition area has connecting rods at least in sections. Such connecting rods are at least partially axially aligned and can be connected directly to the mounting sections and/or be connected to the bearing mount. The rigidity properties for transmitting the bearing forces to the assembly section of the section having connecting rods depend in particular on the arrangement, number and geometry (eg cross section, length and connection to adjoining areas) of the connecting rods.

In one embodiment of the bearing device, the transition area has a plurality of connecting rods connected to the bearing receptacle. In this design, connecting rods are directly connected to the bearing mount. In particular, these connecting rods can be aligned axially or, for example, arranged inclined with respect to the axial alignment. For example, the connecting rods can also have a curvature and, in particular, also run wound around the axis of rotation of the turbomachine, in particular forming a hollow-cylindrical structure.

In one embodiment of the bearing device, at least one mounting section is connected to at least one connecting rod. Accordingly, it is possible for a mounting section to be connected to one side of a connecting rod, which is directly connected to the bearing mount on its opposite side. Correspondingly, it is also possible for two or more assembly sections to be connected with a connecting rod which is connected directly to the bearing mount. Or two or more connecting rods can be connected to an assembly section in order to conduct the bearing forces from the bearing mount via the transition area into the assembly area and finally in particular to load-bearing components of the turbomachine. The arrangement, number and geometry (e.g. cross-section, length and connection to adjoining areas) of the connecting rods are also relevant for the stiffness and force transmission properties of the transition area.

In one embodiment of the bearing device, at least one mounting section and/or at least one connecting rod along it Extension on different cross sections. The rigidity and thus also the power transmission properties of the connecting rods are significantly influenced by their respective cross section and thus the bending moment. Depending on the arrangement of the different cross sections, different rigidity and force transmission properties can be set along a mounting section and/or along a connecting rod and thus along the axial length of the transition area by means of different cross sections along the extension of the bearing rods between the bearing mount and the mounting area.

In one embodiment of the bearing device, at least two connecting rods are connected directly to one another and/or at least two connecting rods are connected to one another via a connecting bridge arranged between the connecting rods. A connection between at least two connecting rods leads to a changed cross section and thus to a bending moment in the area of the connection and correspondingly results in a stiffening of the transition area in the respective section. In this way, the rigidity properties of the transition area can be increased in a defined manner in certain areas/sections by a connection between at least two connecting rods.

In one embodiment of the bearing device, the transition area has at least one closed ring. A closed ring can absorb high forces in the circumferential direction. In the area of a closed ring, the peripheral area therefore has high rigidity, particularly in the peripheral direction. A closed ring interrupts the freedom of movement between connecting rods adjacent to a closed ring.

A certain resilience can be adjusted in the circumferential direction in particular by varying wall thicknesses or recesses in the closed ring.

In one embodiment of the bearing device, at least one assembly section and/or at least one connecting rod has at least one recess and/or at least one constriction and/or at least one thickened area. As already explained, the rigidity and thus also the power transmission properties of the connecting rods are significantly influenced by their respective cross section and bending moment. Depending on the geometry and arrangement of the recess and/or constriction and/or thickening, the weight and rigidity of the transition area can be optimized by at least one recess and/or at least one constriction and/or at least one thickening and the different cross sections connected therewith.

In one embodiment of the bearing device, the bearing seat is designed on the outer peripheral surface to form a squeeze film. Such a squeeze film is usually formed by a film of lubricant that is used to dampen a bearing. In particular, vibrations of the rotor shaft mounted in the bearing mount are damped. Furthermore, the squeeze film also serves to lubricate and cool the bearing point. The at least one section on the outer circumference of the bearing mount has a surface quality that is suitable for forming a squeeze film, in particular circumferentially.

In one embodiment of the bearing device, at least one lubricant channel for supplying the squeeze film with lubricant is arranged in the transition area and in particular in at least one connecting rod. Lubricant from a lubricant supply device is conducted through such a lubricant channel through the transition area for forming the lubricant film. In particular, the lubricant channel opens at at least one position on the outer circumference of the bearing seat. In particular, it is also possible for the lubricant channel to have a number of branches and/or openings, which are distributed around the circumference of the bearing mount. The at least one lubricant channel can also run at least partially through at least one assembly section.

In one embodiment of the bearing device, it is manufactured using an additive manufacturing process. Additive manufacturing processes include, for example, laser sintering, selective laser sintering (SLS), electron beam sintering, electron beam melting (EBM), selective laser melting (SLM) or 3D printing, etc. The material to be added or applied is thereby defined processed in powder form, for example as a metal or metal alloy powder. In this case, the powder is applied in particular in layers to a substrate. Subsequently, the powder layer is solidified in a component area for forming the component using energy radiation, such as a laser beam and/or an electron beam. The next layer of powder is then applied and again selectively solidified by means of energy radiation until the component, in this case the storage facility, is completed. At least one lubricant channel for supplying the squeeze film with lubricant can also be formed by means of the generative manufacturing process.

• 1 eine dreidimensionale Darstellung einer im Stand der Technik bekannten Lagereinrichtung;
• 2 eine schematische Darstellung einer beispielhaften Lagereinrichtung;
• 3 eine beispielhafte erfindungsgemäße Lagereinrichtung in einer Vorderansicht und einer Draufsicht; und
• 4 eine weitere beispielhafte erfindungsgemäße Lagereinrichtung in einer Vorderansicht und einer Draufsicht.

Further features, advantages and possible applications of the invention result from the following description in connection with the figures. It shows

• 1 a three-dimensional representation of a storage device known in the prior art;
• 2 a schematic representation of an exemplary storage facility;
• 3 an exemplary storage device according to the invention in a front view and a plan view; and
• 4 a further exemplary storage device according to the invention in a front view and a top view.

1 shows a three-dimensional representation of a bearing device 1 known in the prior art for a turbomachine. The bearing device 1 has an annular mounting flange 2 and a bearing seat 4 which are connected to one another by a transition area 6 . The transition region 6 has a plurality of spring bars 6a which are spaced evenly apart from one another. The bearing seat 4 has on its inner circumference 4a a bearing seat for receiving at least one roller bearing (not shown) for supporting a rotor of the turbomachine (also not shown). A so-called squeeze film can be formed on the outer circumference 4b of the bearing mount 4 to dampen the bearing.

2 shows a schematic representation of an exemplary bearing device 1 and its bearing points 3. A defined rigidity of this bearing device 1 is mainly set via the transition area 6, which occurs in the in 1 illustrated embodiment is formed by a spring cage. In particular during operation of the turbomachine, radially directed forces F1 act on the transition region 6 and lead to a radial displacement (shown in dashed lines) of the bearing mount 4 relative to the mounting flange 2 . The transition region 6 is designed in such a way that it counteracts a tilting (shown in dotted lines) of the bearing mount 4 relative to the axis of rotation A with the spring rods 6a. When designing the transition area 6, it is therefore necessary to reach a compromise between a defined rigidity and low tilting. The storage device 1 should also have the lowest possible weight.

3 shows an exemplary bearing device 10 according to the invention for bearing a rotor in a turbomachine in a front view and a plan view. The bearing device 10 has an assembly area 12 and a bearing mount 14 which are connected to one another by a transition area 16 . The mounting area 12 has a plurality of mounting sections 15 , ten in the example bearing device, with each mounting section 15 having a fastening opening 13 for fastening the bearing device 10 . The fastening openings 13 are aligned parallel to the axis of rotation A of the turbomachine and are arranged on a circle K running coaxially around the axis of rotation A, with the fastening openings 13 being distributed uniformly in the circumferential direction of the bearing device 10 . In the exemplary bearing device 10, the assembly sections 15, on which the fastening openings 13 are formed, are formed by radially extending rods, on which fastening means can be arranged.

The transition region 12 of the bearing device 10 is formed by connecting rods 17 which are connected on one side to the bearing receptacle 14 and on the other side to a mounting section 15 . The connecting rods run in the axial direction from the bearing mount to the mounting area 12, so that the transition area 16 is in the form of a hollow cylinder. The connecting rods 17 of the exemplary embodiment, like the mounting sections 15, have cross-sections which remain the same along their extension.

The peripheral surface 14a of the bearing seat 14 is designed in such a way that a squeeze film can be formed thereon. The peripheral surface 14a has a surface quality that is particularly suitable for forming a squeeze film. At least one lubricant channel 18 is arranged in the transition region 16 to supply the squeeze film with lubricant. The lubricant channel 18 runs approximately from the end face of a mounting section 15 through a connecting rod 17 and opens into the peripheral surface 14a of the bearing mount 14. A lubricant guided through the lubricant channel 18 serves to form a squeeze film on the outer peripheral surface 14a of the bearing mount 14. The Bearing device 10 can be produced, for example, using an additive manufacturing process. With this method, a bearing device 10 with axially arranged connecting rods 17 can be produced, which requires complex processing, for example by means of a machining process, due to the large volumes of material to be removed. In addition, a lubricant channel 18 can be formed directly during the production of a connecting rod 17 using a generative method.

4 shows a further exemplary storage device 10 according to the invention in a front view and a plan view. The storage facility 10 largely corresponds to that in 3 Bearing device 10 shown match, which is why the same elements are denoted by the same reference numerals. At the in 4 Bearing device 10 shown is a section of the transition region 16 is formed as a hollow-cylindrical wall. In this case, a closed ring 16a in the form of a wall is formed on the transition region 16 . Furthermore, the two connecting rods 17 shown in the center of the view have different cross sections along their extension and are directly connected to one another at a thickened area 16b. A recess 19 is formed in each of the two connecting rods 17 next to the thickening 16b. At a position closer to the bearing seat 14, these two connecting rods 17 are connected to each other via a connecting bridge 16c arranged between them. A constriction 16d reducing the flexural strength of the connecting rod 17 is shown as an example on each of the two connecting rods 17 arranged further to the outside. Both the closed ring 16a and the thickenings 16b, the connection point produced with it, the recesses 19, the constrictions 16d and the connecting bridge 16c serve to set a defined rigidity and deflectability of the transition region 16 and thus of the bearing device 10.

Reference List

1

storage facility

2

mounting flange

4

stock pick-up

4a

inner circumference of the bearing mount

4b

outer circumference of the bearing mount

6

transition area

6a

spring bar

10

storage facility

12

assembly area

13

mounting hole

14

stock pick-up

14a

outer peripheral surface

15

assembly section

16

transition area

16a

closed ring

16b

thickening

16c

connecting bridge

16d

constriction

17

connecting rod

18

lubricant channel

19

recess

A

axis of rotation

F1

power

K

circle

Claims (15)

Bearing device for a turbomachine, in particular for accommodating at least one roller bearing for supporting a rotor, the bearing device (1, 10) having an assembly area (2, 12) and a bearing mount (4, 14) which, through a transition area (6, 16) are connected to one another, characterized in that the assembly area (12) has a plurality of assembly sections (15), each assembly section (15) having at least one fastening opening (13) for fastening the bearing device (10). storage facility claim 1 , characterized in that the fastening openings (13) are aligned parallel to the axis of rotation (A) of the turbomachine and are arranged on a circle (K) running coaxially around the axis of rotation (A). Bearing device according to at least one of the preceding claims, characterized in that the fastening openings (13) are distributed uniformly in the circumferential direction of the bearing device (10). Bearing device according to at least one of the preceding claims, characterized in that the assembly sections (15) are formed by rods which in particular run radially. Storage device according to at least one of the preceding claims, characterized in that at least one section of the transition region (16) is designed as a hollow-cylindrical wall (16a). Storage device according to at least one of the preceding claims, characterized in that the transition region (16) has connecting rods (17) at least in sections. Storage device according to at least one of the preceding claims, characterized in that the transition region (16) has a Having a plurality of connecting rods (17) connected to the bearing mount (14). Storage device according to at least one of the preceding claims, characterized in that at least one mounting section (15) is connected to at least one connecting rod (17). Storage device according to at least one of the preceding claims, characterized in that at least one mounting section (15) and/or at least one connecting rod (17) has different cross sections along its extent. Storage facility according to at least one of the preceding claims, characterized in that at least two connecting rods (17) are connected directly to one another and/or that at least two connecting rods (17) are connected to one another via a connecting bridge (16c) arranged between the connecting rods (17). Bearing device according to at least one of the preceding claims, characterized in that the transition region (16) has at least one closed ring (16a). Storage device according to at least one of the preceding claims, characterized in that at least one mounting section (15) and/or at least one connecting rod (17) has at least one recess (19) and/or at least one constriction (16d) and/or at least one thickening (16b ) having. Bearing device according to at least one of the preceding claims, characterized in that the bearing receptacle (14) is designed on the outer peripheral surface (14a) to form a squeeze film. storage facility Claim 13 , characterized in that at least one lubricant channel (18) for supplying the squeeze film with lubricant is arranged in the transition region (16). Storage device according to at least one of the preceding claims, characterized in that it is produced using an additive manufacturing process.

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