Planet carrier with integrally fixed sliding segments

Abstract

The invention relates to an assembly comprising a planet carrier (103), a planetary gear (109) which is rotatably mounted in the planet carrier (103), and a sliding segment (115a, 115b) which is in the form of an axial bearing or part of an axial bearing for the planetary gear (109). The sliding segment (115a, 115b) is integrally fixed in the planet carrier (103).

Description

[0001] ZF Friedrichshafen AG File 301514 Friedrichshafen 2024-09-03

[0002] Planetary carrier with materially bonded sliding segments

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

[0004] Planetary carriers are known in the prior art that incorporate thrust washers as axial bearings for the planet gears. To prevent the thrust washers from rotating, they are positively fixed in the planetary carrier. For example, German patent application DE 10 2016 219 008 A1 discloses thrust washers with flattened outer edges that correspond to similar flattened surfaces in the planetary carrier.

[0005] Such positive-locking fixings of thrust washers in a planetary carrier fundamentally require molds and corresponding negative molds on both the thrust washer and the planetary carrier. Their production involves increased effort. The corresponding molds must be aligned with each other for assembly. This leads to increased assembly effort.

[0006] The invention is based on the objective of improving an arrangement comprising a planet carrier, a planet gear rotatably mounted in the planet carrier, and a sliding segment compared to the prior art. This objective is achieved by a corresponding arrangement according to claim 1. Preferred embodiments are included in the dependent claims and will become apparent from the following description and the figures.

[0007] A planet carrier is a means for holding planet gears, which are rotatably mounted within the planet carrier relative to it. For each planet gear, the planet carrier can have a planet pin that is rigidly fixed within the planet carrier, meaning it cannot move relative to it. This planet pin holds the respective planet gear, and the planet gear is mounted on this pin. The planet carrier can be fixed against rotation relative to a gearbox housing and / or a housing-mounted structure, or it can be rotatably mounted within the gearbox housing and / or the housing-mounted structure. ZF Friedrichshafen AG File 301514 Friedrichshafen 2024-09-03

[0008] The planet gear of the arrangement according to the invention is rotatably mounted in the planet carrier by means of the sliding segment and optionally by means of further means, such as one or more further sliding segments and / or one or more radial bearings. The sliding segment serves as an axial abutment for the planet gear, against which the planet gear can slide during rotation relative to the planet carrier. Accordingly, the sliding segment forms at least one sliding surface that supports the planet carrier at least in the axial direction. The sliding segment is designed as a thrust bearing or as part of a thrust bearing for the planet gear. Thus, the sliding segment, either alone or in conjunction with one or more further means, forms the thrust bearing.

[0009] An axial bearing is characterized by its ability to absorb forces in the axial direction, in this case, in the direction of a rotational axis of the planet gear. A bearing gap of the axial bearing runs between the sliding segment and the planet carrier. Preferably, the bearing gap is at least partially filled with oil.

[0010] According to the invention, the sliding segment is fixed in the planet carrier by a material bond. In particular, the sliding segment can be fixed in the planet carrier in a rotationally fixed manner by a material bond. In this case, a material bond between the sliding segment and the planet carrier forms a rotationally fixed connection between the sliding segment and the planet carrier.

[0011] The invention is advantageous because material-bonded connections are particularly easy to produce compared to form-fit and force-fit connections, thus saving costs and time. Accordingly, the manufacturing of the arrangement according to the invention is accelerated and reduced in price.

[0012] In a preferred further development, the sliding segment is bonded to the planetary carrier. To create a corresponding connection between the sliding segment and the planetary carrier, only adhesive needs to be applied to the sliding segment and / or the planetary carrier. ZF Friedrichshafen AG File 301514 Friedrichshafen 2024-09-03

[0013] Preferably, the planet carrier is further developed with at least one recess in which the sliding segment is fixed by a material bond. In addition to the material bond fixation according to the invention, the recess also provides a form-fit fixation between the sliding segment and the planet carrier. The combination of material bond and form-fit fixation of the sliding segment according to the further development allows for a combination of the advantages and elimination of the disadvantages of both connection types. In particular, it is possible to optimize the recess for the simplest possible manufacturing at the expense of a completely form-fit fixation of the sliding segment. A correspondingly optimized recess may not fix the sliding segment in a form-fit in one or more directions.For example, it is possible that the sliding segment is not positively locked against rotation relative to the planet carrier around the axis of rotation of the planet gear due to the recess. In a further development, however, the fixing of the sliding segment is supplemented by the material bond, so that the sliding segment is completely and rigidly fixed in the planet carrier, i.e., without the possibility of movement relative to the planet carrier.

[0014] In a further preferred embodiment, the material-bonded connection between the sliding segment and the planet carrier consists in detail between the sliding segment and a bottom surface and / or at least one, preferably two, side surfaces of the recess.

[0015] Preferably, the sliding segment is further developed as a thrust washer. A thrust washer is a sliding segment that has the shape of a toroid, that is, a surface of revolution with a central hole. An axis of symmetry, with respect to which the thrust washer is rotationally symmetrical, runs along the axis of rotation of the planetary gear.

[0016] In a preferred further development, the rotationally fixed fastening of the thrust washer in the planet carrier is exclusively material-bonded. This means, firstly, that the material bond between the thrust washer and the planet carrier forms a rotationally fixed connection. Secondly, there is no positive locking or frictional locking between the thrust washer and the planet carrier that would form a rotationally fixed connection. Therefore, according to ZF Friedrichshafen AG file 301514, Friedrichshafen, September 3, 2024, there is no positive locking or frictional locking between the thrust washer and the planet carrier. According to this further development, the rotationally fixed connection is formed solely by the described material bond.

[0017] Contrary to conventional expectations, it has been shown that the arrangement according to the invention, or a preferred embodiment thereof, can also be used in a highly loaded, slow-rotating gearbox. Accordingly, the arrangement is preferably further developed as part of a wind turbine gearbox.

[0018] A preferred embodiment of the invention is shown in Fig. 1. Specifically, it shows:

[0019] Fig. 1 shows a planetary stage.

[0020] The planetary gear stage 101 shown in Fig. 1 comprises a planet carrier 103 rotatably mounted relative to a housing, a sun gear 105 rotatably mounted relative to the housing, a ring gear 107 fixed to the housing, and a planet gear 109 rotatably mounted in the planet carrier 103. The sun gear 105 is non-rotatably connected to a sun shaft 106. A tooth of the planet gear 109 meshes with a tooth of the ring gear 107 and with a tooth of the sun gear 105.

[0021] The planet carrier 103 has a planet bolt 111. The end faces of this bolt are each received in a cheek of the planet carrier 103 and are positively fixed by means of an interference fit. The planet gear 109 is located on the planet bolt 111. The planet bolt 111 passes through a central recess in the planet gear 109.

[0022] The two cheeks of the planet carrier 103 each have a groove 113a, 113b, which runs rotationally symmetrically around an axis of rotation of the planet gear 109. A thrust washer 115a, 115b is inserted into each of the grooves 113a, 113b. Thus, each groove 113a, 113b accommodates one thrust washer 115a, 115b. ZF Friedrichshafen AG File 301514 Friedrichshafen 2024-09-03

[0023] To prevent the thrust washers 115a, 115b from twisting, they are glued in their respective grooves 113a, 113b. There is therefore an adhesive bond between the thrust washers 115a, 115b and their respective grooves 113a, 113b.

[0024] ZF Friedrichshafen AG File 301514 Friedrichshafen 2024-09-03

[0025] Reference mark

[0026] 101 Planetary Stage

[0027] 103 planetary carriers

[0028] 105 Sun wheel

[0029] 107 Ring gear

[0030] 109 Planetary gear

[0031] 111 planetary bolts

[0032] 113a Nut

[0033] 113b Nut

[0034] 115a Thrust washer

[0035] 115b Thrust washer

Claims

ZF Friedrichshafen AG File 301514 Friedrichshafen 2024-09-03 Patent claims 1. Arrangement comprising a planet carrier (103), a planet gear (109) rotatably mounted in the planet carrier (103), and a sliding segment (115a, 115b) designed as an axial bearing or part of an axial bearing for the planet gear (109); characterized in that the sliding segment (115a, 115b) is fixed in the planet carrier (103) by a material bond.

2. Arrangement according to claim 1 ; characterized in that the sliding segment (115a, 115b) is bonded to the planet carrier (103).

3. Arrangement according to one of the preceding claims; characterized in that the planet carrier (103) has at least one recess (113a, 113b); wherein the sliding segment (115a, 115b) is fixed in the recess (113a, 113b) in a materially bonded manner.

4. Arrangement according to the preceding claim; characterized by a material-bonded connection between the sliding segment (115a, 115b) and a bottom surface and / or at least one side surface of the recess (113a, 113b).

5. Arrangement according to one of the preceding claims; characterized in that a thrust washer (115a, 115b) forms the sliding segment.

6. Arrangement according to the preceding claim; characterized by an exclusively material-bonded, rotationally fixed fixing of the thrust washer (115a, 115b) in the planet carrier (103).

7. Wind turbine gearbox; characterized by an arrangement according to one of the preceding claims.

Images