DE102023101335A1 - Improved sliding coating and applications of this - Google Patents

Abstract

The invention relates to a sliding coating which is preferably used in planetary gears. The sliding coating is particularly suitable for use in gears of a wind turbine or industrial applications, wherein at least one sliding coating consisting of a sliding layer and an intermediate layer is arranged on a base body, ie a component, within the planetary gear.

Description

Brief description of the invention

The present invention relates to a sliding coating which is preferably used in gears, in particular on planetary shafts and/or planetary gears of planetary gears. The sliding coating is particularly suitable for use in gears of wind turbines or industrial applications, wherein at least one sliding coating consisting of an intermediate layer and a sliding layer is arranged on a base body.

Plain bearings known from the state of the art include in particular plain bearing materials made of white metals with alloy components and bronze alloys. Furthermore, the known plain bearings have a lubricating gap for better application. Examples are plain bearing designs as floating bush bearings in planetary gears, as in the EN 102019218116 A1 Also known are solutions with bushings mounted on the shaft or in the bore of the planetary gear, such as in EP2383480B1 , described.

The disadvantage of the above-mentioned solutions, however, is that another thick-walled component with a sliding layer is required.

Furthermore, the disadvantages described above are to be avoided by other methods and plain bearing solutions described in the prior art, in which a sliding layer is applied directly to the planetary shaft. For example, in the EN 102013220063 A1 a plain bearing with a deposited hard material layer and a hardened surface layer as a sliding coating is described.

In the EP3768983B1 a planetary gear with at least one gear wheel mounted on an axle is described, with a sliding layer, preferably made of bronze, welded directly onto an outer surface of the axle, i.e. the steel base body of the planetary shaft, between the gear wheel and the axle or between the axle and an axle mount. However, it is known that welding bronze directly onto a steel base body often leads to cracks in the steel. These cracks, known as "copper penetration", extend a few 1/10 mm from the bonding zone vertically into the steel body. Such cracks often occur immediately after the welding process and are partially filled with bronze. These defects in highly stressed gear components can lead to component failures in the long term with far-reaching consequences. This tendency to crack is known from laser deposition processes, but also from arc welding processes.

The object of the present invention is to avoid the previously described disadvantages of plain bearings and to provide a plain bearing which offers a high level of wear protection, particularly in highly stressed applications such as planetary gears in wind turbines.

The present invention therefore relates to a sliding coating comprising at least one intermediate layer and at least one main layer, wherein the intermediate layer is arranged directly on a base body and the main layer consisting of the actual sliding layer is arranged on this intermediate layer, whereby the sliding layer is spaced from the base body by the intermediate layer. In a preferred aspect of the invention, the base body is at least one planetary shaft or at least one planetary gear in a planetary gear, wherein the base body is particularly preferably made of steel. In a particularly preferred embodiment, the sliding coating is arranged on at least one planetary shaft and/or in a bore of at least one planetary gear within at least one planetary gear.

In one embodiment, the sliding layer of the present invention comprises metal, metal alloys, plastics, ceramics and/or composite materials. However, the sliding layer is preferably made of bronze or a bronze alloy.

In one embodiment, the intermediate layer comprises a non-ferrous metal or a non-ferrous metal alloy, preferably the intermediate layer is nickel and/or copper or alloys thereof. In addition, the intermediate layer preferably has a layer thickness of 2 µm to 1 mm, preferably 2 µm to 50 µm.

The present invention also relates to a method for producing a sliding coating as described above, wherein an intermediate layer is applied to a base body by a welding process, a physical process, a gas-based process and/or a non-remelting process, preferably a galvanic or other wet-chemical coating process, and a sliding layer is then applied to the intermediate layer. Finally, a sliding surface is preferably formed by final, preferably mechanical, processing of the sliding layer.

The present invention further relates to a component comprising at least one sliding coating as described above. In a preferred aspect, this is at least one component of a planetary gear, particularly preferably at least one planetary shaft or at least one planetary gear.

Furthermore, the invention also relates to the use of the above-described sliding coating, of the at least one component in gears, hydraulic pistons, sleeve guides, support bearings, worm racks, screws, guide rails, bearing rings and other components.

The present invention is particularly also directed to a planetary gear comprising at least one planetary shaft on whose outer surface a previously described sliding coating is arranged and/or at least one planetary gear in whose bore a previously described sliding coating is arranged or at least one component is included.

1. a) mindestens einen zuvor beschriebener Gleitbelag innerhalb des Getriebes angeordnet ist;
2. b) mindestens ein zuvor beschriebenes Bauteil; und/oder
3. c) mindestens ein zuvor beschriebenes Planetengetriebe; umfasst ist.

Furthermore, a wind turbine comprising a rotor, a tower and a gearbox is also disclosed, wherein the rotor is connected to the gearbox via a shaft in a torque-transmitting manner and the gearbox is connected to a power generator, wherein

1. a) at least one sliding lining as described above is arranged within the transmission;
2. b) at least one component described above; and/or
3. c) at least one planetary gear as described above;

In a further aspect, the invention also relates to a drive train with at least one previously described component which has a sliding coating, wherein the drive train can transmit the power generated by a power generator to a mechanical unit or vice versa, wherein the drive train comprises a rotor shaft which is connected in a torque-transmitting manner to a transmission which in turn is connected in a torque-transmitting manner to the power generator.

Furthermore, industrial applications with at least one previously described sliding coating, planetary gear, component and/or drive support are also described, which generate power through a power generator which has a torque-transmitting connection to a transmission. In the industrial application, the transmission has a torque-transmitting connection to other mechanical components which can, for example, transmit the power and/or drive other components. The power generator is preferably a generator, a motor or a turbomachine, such as a turbine.

The present invention is characterized by the embodiments in the claims and described in more detail by the embodiments in the following description and the drawings.

Description of the drawings

• 1 Schematic representation of a plain bearing

Detailed description of the invention

The present invention relates to a sliding coating which consists of an intermediate layer and a main layer, wherein the intermediate layer is arranged directly on a base body, preferably a shaft made of steel or the bore of a wheel, and the main layer consisting of the actual sliding layer is arranged on this intermediate layer.

In the following, the articles “a” and all derivatives thereof, as used herein, should generally be understood as “one or more”, unless otherwise specified or evident from the context as the singular form.

Whenever the terms “includes,” “has,” “possesses,” and the like are used in the description or claims, these terms should be understood as the term “having” or “comprising,” i.e., not exhaustive, unless explicitly stated.

In the following, “plain bearing”, “bearing”, “plain bearing”, “plain bearing” and “bearing” are used interchangeably and describe at least one component that makes it possible to guide components that move relative to one another, preferably within a planetary gear, whereby drives can also be realized that have two drive or output branches that can be operated at different speeds.

The term "shaft" describes an elongated, cylindrical machine element that is designed to be movable in order to transmit rotary movements and torques. In a preferred embodiment, this is at least one planetary shaft made of steel of a gearbox in the main drive train of a wind turbine. Although the invention here is described below with reference to planetary shafts of a wind turbine, it is also possible in principle for the sliding coating to be used in other applications. These are, for example, but not limited to the following list, hydraulic pistons, sleeve guides, support bearings, worm gear racks, screws, guide rails, bearing rings and other components. Due to space and efficiency reasons, plain bearings are increasingly being used in planetary stages of gearboxes in wind turbines, which are exposed to strong radial, tangential and axial forces. The present invention is therefore directed in particular at this application in order to reduce wear on the component and the sliding coating as well as the counter-guides, thereby increasing the load-bearing capacity and service life of the plain bearing and thus making it more wear-resistant compared to known bearing arrangements. In addition, the sliding coating made of the two layers should provide effective protection against scoring in the base body, i.e. in the steel bodies, such as in particular steel shafts within gearboxes.

The term "power generator" in the present invention includes any technical device that converts mechanical, chemical, thermal or electromagnetic energy directly into electrical energy and vice versa. Since the present invention is preferably designed for use in wind turbines, the power generator therefore preferably refers to a generator in which energy is transferred from kinetic energy to electrical energy in wind turbines. However, the present invention can also be used in other areas of application, such as in water turbines or gas turbines. Accordingly, a motor, such as an electric motor and/or internal combustion engine, as well as a turbomachine, such as a turbine, are also to be included in the term "power generator" in the present invention, i.e. a technical device that emits mechanical energy, the energy being supplied, for example, by means of electrical, chemical, thermal or electromagnetic energy. In addition, the power generator can also be a generator and motor at the same time.

The term "spaced apart" is used in the present invention to indicate that there is a distance between the base body (1) and the sliding layer (2). This means that the base body (1) and the sliding coating (2) are not in direct contact with each other. The distance between the base body (1) and the sliding layer (2) is generated by an intermediate layer (3) which has direct contact with both, i.e. with the base body (1) and the sliding layer (2), but prevents the sliding layer (2) from coming into contact with the base body (1).

The sliding coating of the present invention consists of at least two layers, wherein an intermediate layer (3) is arranged directly on the base body (1), preferably the steel shaft of a planetary gear and/or a bore in the planetary gear, and a main layer which represents the actual sliding layer (2).

The sliding layer (2) is made of the known sliding bearing materials, such as metal or metal alloys, plastics, such as polytetrafluoroethylene (PTFE), ceramics or composites, such as metal-polymer or fiber-reinforced sliding bearing materials. In the present invention, a sliding layer (2) made of bronze or a bronze alloy is preferably used. The sliding layer (2) is spaced from the base body (1) by the intermediate layer (3), such as the 2 can be seen. In one aspect of the invention, the sliding layer (2) is preferably arranged on at least one planetary shaft or in a bore of at least one planetary gear of at least one planetary gear, with at least one intermediate layer (3) being arranged between the respective component and the sliding layer (2), ie the intermediate layer (3) prevents direct contact between the base body (1) and the sliding layer (2). In a particularly preferred embodiment, such a sliding coating is used in at least one planetary gear of a wind turbine.

The intermediate layer (3) is arranged directly on the base body (1), i.e. it is in direct contact with the base body (1) and prevents contact between the main layer, i.e. the sliding layer (2), and the base body (1). The intermediate layer (3) is applied directly to the base body (1), which is preferably made of steel, in particular the planetary shaft and/or the planetary gear, in relation to a planetary gear. The intermediate layer (3) can be applied by a welding process, a non-melting process, preferably a galvanic or other wet-chemical coating process, a physical process such as sputtering, and/or a gas-based process such as physical vapor deposition (PVD). A non-ferrous metal or a non-ferrous metal alloy is preferably used for the intermediate layer (3).

Tests have surprisingly shown that a sliding coating made of two layers, in which the actual sliding layer (2) made of a plain bearing material, in particular bronze, is separated from the steel base body by an intermediate layer (3), in particular made of nickel or copper, leads to a suppression of crack formation in the base body (1), thereby increasing the load-bearing capacity and wear resistance. activity of the sliding bearing is increased. With a layer thickness of the intermediate layer (3) in the range of 2 µm to 1 mm, preferably from 2 µm to 50 µm, the positive effect on the base body (1) was most pronounced.

After the intermediate layer (3) has been applied, the sliding layer (2) is then applied to it. Depending on the material applied, the intermediate layer (3) can be coated with the sliding layer (2) using application techniques known in the art, such as galvanic coating, welding, bonding, pressing and/or other methods.

A sliding surface (5) is then created by a final processing of the sliding layer (2), preferably mechanical processing. The processing involves known processing methods for producing a specific surface, such as turning, milling, honing, laser processing, electrochemical processes and/or chemical processing.

Due to the intermediate layer (3), which is arranged between the base body (1) and the sliding layer (2) and preferably prevents direct contact between the two layers, the disadvantages described in the prior art are avoided, such as the use of thicker-walled components with a sliding layer or cracking within the base body (1) and the sliding layer (2) due to bimetallic corrosion.

Furthermore, in addition to the sliding coating made of two layers, namely the intermediate layer (3) and the sliding layer (2), the present invention also relates to a component on which such a sliding coating is arranged. In a preferred aspect of the present invention, this is at least one component of a planetary gear, particularly preferably a planetary shaft or a planetary gear in the bore of which the sliding coating consisting of at least one sliding layer (2) and at least one intermediate layer (3) is arranged, wherein the intermediate layer (3) is in direct contact with the component and the sliding layer (2) is spaced from it by the intermediate layer (3).

The sliding coating can be used in various applications, such as different types of gears, hydraulic pistons, spindle guides, support bearings, worm gear racks, screws, guide rails, bearing rings and other mechanical machine elements. In a preferred aspect of the invention, the sliding coating is used in one or more planetary stages of gearboxes of wind turbines, since it was surprisingly shown in test runs that a sliding coating made of at least one sliding layer (2) which consists of at least one intermediate layer (3) and spaced the sliding layer (2) from the base body (1), increases the load-bearing capacity of the components of the planetary gear, in particular the planetary shaft or the planetary gear, and thus makes the gear more wear-resistant.

Consequently, the invention also relates to at least one planetary gear with a sun gear, a ring gear and a planet carrier in which several planet gears are mounted, wherein several radial plain bearings are provided for mounting the planet gears, wherein the previously described sliding coating is arranged on at least one planet shaft and/or a bore of at least one planet gear. In a preferred embodiment, the planetary gear comprises several planetary stages. In addition, a combination of one or more planetary stages and spur gear stages can also be provided. Depending on the application, the gear with at least one sliding bearing according to the invention can be connected to a power generator, such as a generator or a component which converts kinetic energy into motion energy, such as a rotor of a wind turbine, so that power is supplied to the gear. The planetary gear with at least one component on which a sliding coating according to the invention is arranged can be used in various applications as described above, such as in particular drive trains, wind turbines or industrial applications.

Depending on the application and the material used, in addition to the sliding coating, at least one lubrication can also be provided within the gear unit in one embodiment.

In this context, the present invention further relates to a wind turbine. The rotor is usually mounted on a tower and can have different shapes and numbers of rotor blades, the task of the rotor is to convert the kinetic energy of the wind into rotational energy. In one aspect, the wind turbine comprises a rotor, a tower and a gear, wherein the rotor is connected to the gear via a shaft in a torque-transmitting manner, which comprises at least one planetary gear, which preferably comprises a sliding coating on a planetary shaft and/or a bore of at least one planetary gear, which consists of a sliding layer (2) and an intermediate layer (3), wherein the intermediate layer (3) separates the sliding layer (2) and thus the sliding surface (5) from the base body (1), i.e. the planetary shaft and/or which is spaced from the planetary gear. The gearbox is in turn connected to a power generator.

Furthermore, the invention also relates to a drive train with at least one component that has a sliding coating according to the invention, at least one previously described transmission comprising at least one sliding coating or a previously described arrangement, wherein the drive train can transmit the power generated by a power generator to a mechanical unit or vice versa, wherein the drive train comprises a rotor shaft that is connected to a transmission in a torque-transmitting manner, which in turn is connected to the power generator in a torque-transmitting manner. The drive train preferably comprises a rotor shaft that is connected to a transmission in a torque-transmitting manner, which in turn is connected to the power generator in a torque-transmitting manner.

In industrial applications, power is generated by a power generator which has a torque-transmitting connection to a gearbox. This gearbox has at least one component, preferably at least one planetary shaft and/or at least one planetary gear, which have a sliding coating according to the invention consisting of a sliding layer (2) and an intermediate layer (3), wherein the intermediate layer spaced the sliding layer (2) and thus the resulting sliding surface (5) from the respective component on which the sliding coating is arranged. In the industrial application, the gearbox has a torque-transmitting connection to other mechanical components which can, for example, transmit the power and/or drive components. The power generator is preferably a generator, a motor or a turbomachine, such as a turbine.

These and other embodiments of the present invention are disclosed in and encompassed by the specification and examples. Additional literature on known materials, methods and applications that can be used in accordance with the present invention can be accessed from public libraries and databases, for example, using electronic devices. A more complete understanding of the invention can be obtained by reference to the figures, which are provided for the purpose of illustration and are not intended to limit the scope of the invention.

List of reference symbols

1

Planetary shaft

2

Sliding layer

3

Intermediate layer

4

Base body

5

Sliding surface

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions.

Cited patent literature

• DE 102019218116 A1 [0002]
• EP 2383480 B1 [0002]
• DE 102013220063 A1 [0004]
• EP 3768983 B1 [0005]

Claims (13)

Sliding coating comprising at least one intermediate layer (3) and at least one main layer, wherein the intermediate layer (3) is arranged directly on a base body (4) and the main layer consisting of the actual sliding layer (2) is arranged on this intermediate layer (3), whereby the sliding layer (2) is spaced from the base body (4) by the intermediate layer (3). Sliding coating according to Claim 1 , wherein the base body (4) is at least one planetary shaft or at least one planetary gear in a planetary gear, wherein the base body (4) is preferably made of steel. Sliding coating according to Claim 1 or 2 , wherein the sliding layer (2) comprises metal, metal alloys, plastics, ceramics and/or composite materials, wherein the sliding layer (2) is preferably made of bronze or a bronze alloy. Sliding coating according to one of the Claims 1 until 3 , wherein the sliding layer (2) is spaced from the base body (1), which is at least one planetary shaft or in a bore of at least one planetary gear of at least one planetary gear, by the intermediate layer (3). Sliding coating according to one of the Claims 1 until 4 , wherein the intermediate layer (3) consists of a non-ferrous metal or a non-ferrous metal alloy, preferably wherein the intermediate layer (3) is nickel, a nickel alloy, copper and/or a copper alloy. Sliding coating according to one of the Claims 1 until 6 , wherein the intermediate layer (3) has a layer thickness of 2 µm to 1 mm, preferably of 2 µm to 50 µm. Method for producing a sliding coating according to one of the Claims 1 until 6 , wherein an intermediate layer (3) is applied to a base body (4) by a welding process, a physical process, a gas-based process and/or a non-remelting process, preferably a galvanic or other wet-chemical coating process, and subsequently a sliding layer (2) is applied to the intermediate layer. Procedure according to Claim 8 wherein a sliding surface (5) is formed by machining the sliding layer (2), preferably mechanical machining. Component comprising at least one sliding coating according to one of the Claims 1 until 6 , preferably wherein it is at least one component of a planetary gear, particularly preferably at least one planetary shaft or at least one planetary gear. Use of the sliding coating according to one of the Claims 1 until 6 , of at least one component according to Claim 9 in gears, hydraulic pistons, quill guides, support bearings, worm racks, screws, guide rails, bearing rings and other components. Planetary gear comprising at least one planetary shaft with a sliding coating according to one of the Claims 1 until 6 , at least one planetary gear in the bore of which a sliding coating according to one of the Claims 1 until 6 is arranged and/or a component according to Claim 9 is included. Wind power plant comprising a rotor, a tower and a gearbox, wherein the rotor is connected to the gearbox via a shaft in a torque-transmitting manner and the gearbox is connected to a power generator, wherein a) at least one sliding coating according to one of the Claims 1 until 6 is arranged within the gearbox; b) at least one component according to Claim 9 ; and/or c) at least one planetary gear according to Claim 11 ; is included in the wind turbine, preferably its gearbox. Drive train with at least one component that has a sliding coating according to one of the Claims 1 until 6 wherein the drive train can transmit the power generated by a power generator to a mechanical unit or vice versa, wherein the drive train comprises a rotor shaft which is connected in a torque-transmitting manner to a gearbox which in turn is connected in a torque-transmitting manner to the power generator.

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