Axial sliding bearing having rigid sliding segments

Abstract

The invention relates to an arrangement for a wind turbine gear mechanism, comprising a planetary carrier (101), an axial sliding bearing and a planetary gear (109) which is rotatably mounted in the planetary carrier by means of the axial sliding bearing. The axial sliding bearing has one or more sliding segments (111) which are each rigidly fixed by a cylindrical portion in a cylindrical recess (113) of the planetary carrier.

Description

[0001] ZF Friedrichshafen AG Friedrichshafen

[0002] Axial guide bearings with rigid sliding segments

[0003] The invention relates to an arrangement according to the preamble of claim 1.

[0004] Wind turbine gearboxes with planetary stages are known from the state of the art, in which the planetary gears are supported by plain bearings. Thrust washers are used as axial plain bearings.

[0005] The invention is based on the object of improving a wind turbine gearbox over the prior art. This object is achieved by an arrangement according to claim 1. Preferred developments are contained in the subclaims and will become apparent from the following description and the figures.

[0006] The arrangement according to the invention is designed for use in a wind turbine gearbox. It comprises a planetary carrier, an axial plain bearing, and a planetary gear. The planetary carrier is mounted fixedly to the housing or rotatably in the housing or a structure fixed to the housing. The planetary gear is rotatably mounted in the planetary carrier. In particular, it can be rotatably mounted on a planetary pin that is rigidly fixed, i.e., without the possibility of relative movement, in the planetary carrier. Preferably, the planetary gear is mounted by means of a radial plain bearing, i.e., a plain bearing that supports the planetary gear in the radial direction with respect to a rotational axis of the planetary gear.

[0007] An axial plain bearing is a plain bearing that supports the component to be supported axially, i.e., in the direction of the rotational axis, relative to the component's axis of rotation. In this case, the component to be supported is the planetary gear. Accordingly, the planetary gear is rotatably mounted in the planet carrier by means of the axial plain bearing and, if necessary, additional axial and / or radial bearings, which are also preferably designed as plain bearings.

[0008] According to the invention, the axial plain bearing has one or more sliding segments. In particular, the axial plain bearing can consist of one or more sliding segments. The sliding segments are preferably made of a plain bearing material, for example, an alloy containing copper, tin, zinc, aluminum, and / or lead.

[0009] A sliding segment is a means having a sliding surface. In this case, a sliding surface of the planetary gear forms a sliding surface pair with the sliding surfaces of one or more sliding segments. The sliding surfaces of each sliding surface pair are designed to transmit a force via a lubricating gap extending between the sliding surfaces or via direct contact. In this case, the force is axial. The planetary gear can form the aforementioned sliding surface in one piece or, for example, have a thrust washer that forms the sliding surface.

[0010] The one or more sliding segments each form a cylindrical section. This section can extend over the entire sliding segment or only part of the sliding segment. The one or more sliding segments are rigidly fixed to the respective cylindrical section, i.e., without any possibility of relative movement, in a cylindrical recess in the planet carrier. For each of the one or more sliding segments, the planet carrier therefore forms a cylindrical recess in which the sliding segment is rigidly fixed with its cylindrical section. Accordingly, the planet carrier has one or more such recesses. These are preferably arranged in at least one cheek of the planet carrier. The planet carrier and / or the at least one cheek preferably form the recesses in one piece.

[0011] "Cylindrical" refers to the shape of a cylinder. The cylindrical sections of the one or more sliding segments are therefore shaped like a cylinder. This can be a circular cylinder or a cylinder whose base deviates from the shape of a circle. The recesses of the planet carrier are shaped like a corresponding hollow cylinder.

[0012] The invention is advantageous because the one or more sliding segments can be used regardless of the diameter of the planetary gear and the planetary pin. This allows for the reuse of identical segments in different transmissions. Since the sliding segments only need to protrude minimally from the flange of the planetary carrier, the installation space required in the axial direction is also reduced.

[0013] The one or more sliding segments are preferably fixed in the respective recess of the planet carrier by force-locking. In a preferred embodiment, this force-locking is achieved by an interference fit. An interference fit is advantageous because it can be produced easily and reliably. For example, it is possible to drive the one or more sliding segments into the respective recess of the planet carrier using a hammer.

[0014] In a preferred embodiment, the one or more sliding segments are each designed as a single piece and / or as separate pieces. A design as separate pieces means that the one or more sliding segments are not in direct contact with each other and, in particular, are not connected to each other as a single piece.

[0015] In a preferred embodiment, the one or more sliding segments have a cylindrical basic shape. This is advantageous because cylindrical bodies can be easily manufactured from cost-effective bar stock.

[0016] The basic shape of a body refers to the shape of an original body from which the first-mentioned body was created by eliminating individual regions, for example by inserting recesses, and / or by adding individual regions, or whose shape corresponds to the shape of the first-mentioned body. The shape of the one or more sliding segments therefore corresponds to a cylinder or was created from a cylinder by adding recesses and / or by adding individual regions. In particular, the shape of the one or more sliding segments can each have been created from a cylinder by rounding or chamfering one or more edges. Preferably, one edge running at a transition from a lateral surface of the cylinder or of the respective sliding segment to the sliding surface of the respective sliding segment is rounded. Preferred exemplary embodiments of the invention are illustrated in the figures.

[0017] Corresponding reference numbers indicate identical or functionally equivalent features. Specifically, the following shows:

[0018] Fig. 1 a planetary stage; and

[0019] Fig. 2 different variants of sliding segments.

[0020] A planetary carrier 101 shown in Fig. 1 has a first flange 103 and a second flange 105. A planetary pin 107 extends between the flanges 103, 105 and is fixed in both flanges 103, 105. A planetary gear 109 is rotatably mounted on the planetary pin 103 by means of a radial plain bearing.

[0021] Circular cylindrical sliding segments 111 serve as axial plain bearings for the planetary gear 109. The first cheek 103 and the second cheek 105 each have several such sliding segments 111.

[0022] The sliding segments 111 are each recessed 113 in the first cheek 103 or the second cheek 105 and are frictionally fixed in the respective recess 113 by means of an interference fit. Under axial load, the planetary gear 109 is supported by the sliding segments 111 in the respective cheek 103, 105. The planetary gear 109 comes into contact with the sliding segments 111.

[0023] The sliding segments 111 can be designed in various ways. Corresponding embodiments are shown in Fig. 2. In a first embodiment 111a, the sliding segments 111 have a cylindrical basic shape with rounded edges.

[0024] In a second embodiment 111b and a third embodiment 111c, the sliding segments consist of a first section 201 and a second section 203. The first section 201 and the second section 203 each have a circular-cylindrical basic shape with rounded edges. What the second embodiment 111b and the third embodiment 111c have in common is that the respective sliding segment 111 is non-positively fixed to the first section 201 by means of an interference fit in a corresponding recess in the first cheek 103 or the second cheek 105. The second section 203 is larger in diameter than the first section 201.

[0025] The second embodiment 111b is characterized in that the second section 203 is recessed into a corresponding recess in the first cheek 103 or the second cheek 105. This benefits the installation space requirement in the axial direction. However, the recess for the second section 203 must be drilled in an additional manufacturing step.

[0026] According to the third embodiment 111c, the second section 203 is therefore located completely outside the cheeks 103, 105. The second section 203 rests on a side surface of the first cheek 103 or the second cheek 105. Only the first section 101 is recessed in the respective cheek 103, 105. In order to minimize the axial space requirement, the second section 203 is designed to be correspondingly flat.

[0027] Reference symbol

[0028] planet carrier

[0029] cheek

[0030] cheek

[0031] Planetary bolt

[0032] planetary gear

[0033] Sliding segment a embodiment b embodiment c embodiment recess section

[0034] Section

Claims

Patent claims 1. An arrangement for a wind turbine gearbox, comprising a planetary carrier (101), an axial plain bearing, and a planetary gear (109) rotatably mounted in the planetary carrier (101) by means of the axial plain bearing; characterized in that the axial plain bearing has one or more sliding segments (111), each of which is rigidly fixed by a cylindrical section in a respective cylindrical recess (113) of the planetary carrier (101).

2. Arrangement according to claim 1; characterized in that the one or more sliding segments (111) are each fixed in the respective recess (113) by means of an interference fit.

3. Arrangement according to one of the preceding claims; characterized in that the one or more sliding segments (111) are each designed as one piece and / or as separate pieces.

4. Arrangement according to one of the preceding claims; characterized in that the one or more sliding segments (111) have a cylindrical basic shape.

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