WO2023213356A1

WO2023213356A1 - Annular thrust plate, planetary transmission with a thrust plate of this type, and lubricating device for a planetary transmission

Info

Publication number: WO2023213356A1
Application number: PCT/DE2023/100317
Authority: WO
Inventors: Andreas Kirschner; Wolfgang Fugel; Frank Schoenstein
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2022-05-05
Filing date: 2023-05-03
Publication date: 2023-11-09
Also published as: CN118871695A; DE102022111082B3

Abstract

An annular thrust plate for a planetary gear (8), mounted via an anti-friction bearing (5), of a planetary transmission (1), wherein a plurality of axial depressions (102, 202) which are offset around the circumference and extend to the outer circumference are provided on one plate side (101, 201) in an outer plate portion which is spaced apart radially from the inner circumference, and flat elevations (103, 203) which correspond with the depressions (102, 202) are provided on an opposite plate side (104, 204), wherein the plurality of flat elevations (103, 203) form a segmented first thrust surface (107, 207) which is adjoined radially on the inside by a circular ring-shaped second thrust surface (108, 208) which is formed via a non-deformed inner plate portion (105, 205) and is recessed axially with respect to the first thrust surface (107, 27).

Description

Annular thrust washer, planetary gear with such a thrust washer and lubricating device for a planetary gear

The invention relates to an annular thrust washer for a planetary gear of a planetary gear mounted via a rolling bearing.

Such an annular thrust washer is designed and designed for use in a planetary gear, for example a motor vehicle. Such a planetary gear usually has a planet carrier with at least one, usually several, off-center and offset from one another in the circumferential direction, which are mounted on bearing pins provided on the carrier side via respective roller bearings. Such an annular thrust washer, which has a central receiving hole, is arranged on the bearing pin and, viewed axially, is located between the planet gear and the planet carrier, so that the planet gear, which is slightly axially displaceable on the bearing pin, can run axially against the thrust washer and via this axially on the planet carrier is supported. Since the planetary gear rotates during operation, the bearing area must be lubricated with a lubricant. For this purpose, it is known to supply the lubricant, usually oil, via the bearing pin, which is designed as a hollow pin and has an axial bore and at least one radial bore, so that the lubricant can be supplied axially to the bolt and exit radially into the bearing area.

In order to be able to distribute the lubricant in the area of the axial support of the planet gear, in a thrust washer known from DE 10 2012 016 823 A1, several radially extending recesses are provided on the inner circumference, which open into lubricant grooves running radially to the outer circumference of the disk. The lubricant collecting on the bearing pin or flowing along it can reach the lubricant grooves via the recesses and into the axial support area via these, so that lubrication is also possible there. The thrust washer itself is designed as a simple flat disk on which, on the one hand, the planetary gear is axially supported, but also the rolling elements. The implementation of a lubricant supply via the bearing pin(s) is complex because special, drilled pins must be used in conjunction with a corresponding supply structure for supplying the lubricant to the pin(s).

The invention is based on the problem of providing a thrust washer that enables improved lubricant supply to the bearing area and at the same time axial support of both the planetary gear and the rolling bearing.

To solve this problem, according to the invention, an annular thrust washer is characterized in that on one side of the disk in an outer disk section that is radially spaced from the inner circumference, a plurality of axial depressions offset around the circumference and extending towards the outer circumference are provided, and on an opposite side of the disk there are flat elevations corresponding to the depressions, whereby the plurality of flat elevations form a segmented first contact surface, which is adjoined radially on the inside by an annular second contact surface formed via an undeformed inner disk section and which is axially set back from the first contact surface.

The thrust washer according to the invention is characterized by a specific disk profile, via which, on the one hand, two separate contact surfaces lying on different radial planes, which are axially offset from one another, are realized, as well as channels or channel or lubricant guide structures that are open radially towards the outer circumference, via which from radial Lubricant can be supplied outside, which reaches the rolling bearing area via these channels. This lubricant supply can take place from the sun gear side of the planetary gear.

The thrust washer is correspondingly profiled by mechanical forming, in particular embossing, of a metal sheet. It has a plurality of axial recesses offset around the circumference, which are provided in a first outer disk section and extend to the outer circumference. On the opposite side of the disk, corresponding elevations arise due to the forming process, which alternate with axially set back, non-formed disk areas. Not this one deformed disc areas, i.e. the areas between two adjacent elevations, form, viewed radially, a channel that is open towards the outer circumference, through which lubricant can flow radially from the outside.

The several depressions or the elevations provided on the other side of the disk are adjoined radially on the inside by an inner disk section which is undeformed and annular. Two contact surfaces are now formed or defined via these elevations and the inner, undeformed annular disk section. A segmented first contact surface is formed over the individual flat elevations. This first contact surface is located radially further out and serves to contact the end face of the planetary gear. The inner, undeformed disk section forms an annular second contact surface on which the rolling bearing or the cage of the rolling bearing is axially supported, this second contact surface being set back axially with respect to the first, segmented contact surface. The cage therefore protrudes slightly axially over the planet gear or its starting face. This results in a quasi-stepped design or profiling of the thrust washer, forming two separate, axially offset thrust surfaces in conjunction with a channel structure that is open radially outwards. A radial lubricant inlet is possible via this channel structure, via which on the one hand the first and the second contact surfaces are supplied with lubricant, but in particular also the rolling bearing, i.e. the bearing area on the bearing pin, since the lubricant can flow directly via the channel structure to the cage and thus to the rolling bearing .

The thrust washer according to the invention therefore ensures, on the one hand, the best possible axial support of the planetary gear as well as the roller bearing or the cage via the two contact surfaces, and a very good supply of lubricant can also be achieved via the channel structure realized by the profiling. This in turn means that the use of specific, hollow-drilled bearing pins can be dispensed with, since lubricant can only be supplied via a supply on the sun gear side, i.e. from the radial inside in relation to the planet gear, and via the radially open channel structure of the thrust washer. As described, the deformations or elevations are formed by corresponding deformation of the metal strip from which the disc is made. In this case, each elevation can expediently connect with its inner end to the inner disk section via a cranked transition zone, the disk thickness in the area of the transition zone being less than the disk thickness in the area of the inner disk section. This means that there is a relatively sharp, i.e. immediately stepped, transition from the inner disk section to the depression or elevation, with a significant thinning of material resulting from forming in this area. The wall thickness in this transition zone is consequently reduced to a smaller extent than the wall thickness in the inner pane section, over which an immediate step can be formed, which in turn leads to the surface of the elevation adjoining the surface of the inner pane section almost immediately, hence the outer first contact surface directly adjoins the inner second contact surface. This in turn enables a correspondingly large-area design of the first contact surface, combined with a correspondingly large-area support for the planetary gear. The disk thickness is expediently the same in the area of the elevation and in the area of the inner disk section, which means that there is no change in the metal strip thickness due to the forming, except in the immediate forming area, where the formed sections or elevations merge into the inner disk section or, viewed in the circumferential direction , connect radially to the undeformed disk sections that define the channel structure.

A planetary carrier of a planetary gear usually has two cheeks, between which the bearing pins, the planetary gears and the rolling bearings are arranged. A thrust washer is arranged between each cheek of the planet carrier and the end face of the planet gear, which means that two thrust washers are ultimately provided per planet gear in such a carrier design. Only one of the thrust washers can be designed according to the invention, while the other thrust washer is a simple, flat thrust washer. Alternatively, both thrust washers can of course also be profiled according to the invention. In the assembly position, the thrust washer according to the invention lies with the side from which the depressions are introduced adjacent to the cheek of the planet carrier, while the side on which the elevations protrude lies adjacent to the planet gear. The thrust washer is of course accommodated with play, so that depending on the operating situation, i.e. if there is no starting, there are radial gaps between the carrier cheek and the thrust washer on the one hand or between the thrust washer and the planetary gear or the rolling bearing cage on the other hand, while in the case of starting The thrust washer rests on the cheek and the planet gear rests on the first contact zone and the cage rests on the second contact zone. In this case, the undeformed disc areas lying between the elevations and defining the channel structure are encroached upon by the planetary gear, so that an almost closed channel ultimately results. The lubricant supplied from the sun gear side from the radial inside can now enter these channels and be distributed accordingly from there. However, an inflow of lubricant is also possible into the depressions, which are of course also radially open and which, in the event of a start, are encroached upon by the carrier trough, so that corresponding pockets are formed over them. If these are closed, a kind of lubricant reservoir is formed, via which the contact area between the thrust washer and the carrier trough is lubricated, especially when the thrust washer rotates relative to the carrier.

Instead of a correspondingly closed design of these pockets, it is conceivable according to an expedient development of the invention that each elevation connects with its inner end to the inner disk section via one or the cranked transition zone, with at least some of the transition zones, preferably each transition zone, in each case at least an axial opening is provided. One side of the pane essentially communicates with the other via this axial opening. Lubricant that flows into the recesses, i.e. into the area between the carrier cheek and the thrust washer, can flow through these openings provided at the base of the recesses to the other, inner side of the disk facing the planetary gear, so that the volume of lubricant that can be supplied can be increased even further. The pockets formed via the depressions are therefore opened radially via these openings, so that a Flow is possible and the lubricant can therefore flow in both via the channels located between the elevations and via the volumes provided by the depressions.

The respective opening can be designed as an arcuate elongated hole which extends in the circumferential direction over at least half the circumferential length of the elevation, in particular over the entire circumferential length of the elevation. The longer the slot, the larger the flow cross section and the larger the amount of lubricant that can be supplied. Such a depression is preferably formed in the forming step.

The corresponding disk profiling not only provides a lubricant supply structure, be it only via the channels or channel structure, or also via the recess volumes in connection with the openings, but also takes part in the lubricant outflow. The lubricant can, not least because it is driven outwards via the rotating parts due to centrifugal force, also flow radially outwards again via the channels or openings. This means that just as the inlet takes place via the corresponding profile structures between the planetary gear and the disk on the one hand or the thrust washer and the carrier cheek on the other hand, the lubricant is also discharged via the corresponding structures.

The profiling is preferably circumferentially symmetrical, which means that the depressions or elevations are offset equidistantly around the circumference. For example, four recesses or elevations are provided on the thrust washer, so that four channels open radially outwards are formed between the elevations, as well as four pockets defined over the recesses, possibly together with corresponding openings. Such an equidistant profile design is particularly useful if the thrust washer is rotatably seated on the bearing pin. However, it is also conceivable to secure the thrust washer in its position on the bearing pin using an anti-twist device. In addition to the thrust washer itself, the invention also relates to a planetary gear, which is particularly suitable for a vehicle, in particular a vehicle gear. The planetary gear is preferably part of a drive train of an electric drive, in particular an electric axle, or a hybrid drive train. In addition to a sun gear unit, it has a planet carrier on which at least one bearing pin is arranged, and a planet gear which is mounted on the bearing pin via a rolling bearing comprising several rolling elements guided in a cage. The arrangement is framed by a ring gear with which the planet gears also mesh. For axial support of the planet gear and the rolling bearing or cage, a thrust washer according to the invention is now provided on at least one side between a cheek of the planet carrier and the planet gear or cage. If the planet carrier has two cheeks, a thrust washer is also provided on the other side, which is either a simple, flat, i.e. unprofiled thrust washer, or also a thrust washer that is profiled according to the invention. Depending on how the lubricant supply coming from the sun gear is designed, a thrust washer according to the invention can only be provided on one side if the lubricant is only supplied from the inside on this side. If lubricant supply is provided on both sides, two thrust washers according to the invention are expediently integrated.

According to the invention, the first contact surface formed over the elevations forms a first contact zone for the planetary gear, while the circular, axially recessed second contact surface forms a contact zone for the cage of the rolling bearing which protrudes axially over the planetary gear.

In a further development of the invention, a lubricant structure is formed via the thrust washer, with the lubricant guided from the radial outside of the thrust washer either being guided to the first and second contact zones via guide channels formed between two adjacent elevations and open radially towards the outer circumference. In this embodiment, the transition zones are not provided with openings, which means that the pockets formed via the depressions are closed. Alternatively, it is also conceivable that the lubricant is formed between two adjacent elevations and is open radially towards the outer circumference Guide channels as well as the depressions provided on the other side of the disk, which are open radially towards the outer circumference, and the subsequent openings are guided to the first and second contact zones. In this second variant, an inflow of lubricant via the recess-side volumes is therefore also possible. Regardless of the type of lubricant guiding structure that is formed via the thrust washer, the lubricant flows into the area of the first and second thrust surfaces, so that the contact and friction zones there are lubricated, as of course also towards the rolling bearing after an inflow of lubricant directly to the rolling bearing cage, which is openly accessible via the channel structure and, if applicable, the openings, and thus the rolling elements.

Finally, the invention also relates to a lubricating device for a planetary gear with a lubricant supply structure, which is preferably implemented via a supply structure on the sun gear side. The lubricating device comprises a thrust washer of the type described above, wherein the lubricant supplied via the lubricant supply structure is guided from the radial outside to the first and second thrust zones either via guide channels formed between two adjacent elevations and open radially towards the outer circumference, or wherein the lubricant is both via guide channels formed between two adjacent elevations and open radially towards the outer circumference as well as via the recesses provided on the other side of the disk and open radially towards the outer circumference and the subsequent openings from the radial outside to the first and second contact zones.

The invention is explained below using exemplary embodiments with reference to the drawings. The drawings are schematic representations and show:

Figure 1 is a partial view of a planetary gear according to the invention,

Figure 2 is a perspective view of a thrust washer according to the invention of a first embodiment, Figure 3 is a top view of the thrust washer from Figure 2,

Figure 4 is a sectional view along line IV - IV from Figure 3,

Figure 5 is an enlarged partial view of area V from Figure 4,

6 shows a perspective view of a start-up note according to the invention of a second embodiment,

Figure 7 is a top view of the thrust washer from Figure 6,

Figure 8 is a sectional view through the thrust washer from Figure 7 along the line VIII - VIII, and

Figure 9 is an enlarged partial view of area IX from Figure 8.

Figure 1 shows a schematic representation of a planetary gear 1 according to the invention in a partial view. Such a planetary gear 1 has a sun gear unit, not shown here, whose axis of rotation defines the main axis of rotation of the gear. The sun gear unit has a sun gear and a sun shaft, wherein the sun gear is arranged on the sun shaft and is either a separate, attached component or in one piece with the sun shaft. A plurality of planet gears rotatably mounted on a planet carrier usually mesh with the sun gear, the sun gear being arranged concentrically within the planet gear arrangement. The planet gears also mesh with a ring gear surrounding them. The basic structure of such a planetary gear is known.

The detail of the planetary gear 1 shown in Figure 1 shows the planet carrier 2 consisting of two cheeks 3, to which a bearing bolt 4, which is a simple, solid material bolt, is attached. The bolt 4 extends from one cheek 3 to the other. A planetary gear 8 is rotatably mounted via a rolling bearing 5 comprising a cage 6 and rolling elements 7 guided or held therein in the form of needles. The planet gear 8 has external teeth 9 with which it meshes with the sun gear 10 indicated here on the one hand, and with the ring gear on the other hand, as described.

Between the planet gear 8 and the rolling bearing 5 and each of the cheeks 3 there is a thrust washer 11, 12 arranged, against which the planet gear 8 with its respective axial end face as well as the cage 6, which protrudes slightly axially over the planet gear 8 on both sides, can run , so it is axially supported there, while each of the thrust washers 11, 12 is supported axially on the respective cheek 3. In the unloaded state, i.e. when there is no starting case, there is always a small gap between the thrust washer 11, 12 and the cheeks 3 on the one hand and the planet gear 8 and the cage 6 on the other hand, while in the case of starting there is a corresponding one on one of the thrust washers 11, 12 facility is given.

As Figure 1 shows, the thrust washer 11 is a simple, flat disk, which is designed as an annular disk and has a central receiving hole with which it sits on the bearing pin 4 in a known manner.

In contrast, the thrust washer 12, which is a thrust washer according to the invention, is designed to be stepped, i.e. not flat. It also has a receiving hole through which the bearing pin 4 reaches. The stepped design of the thrust washer 12 results in an improved supply of the lubricant, i.e. the oil, which is supplied from the radial inside, as shown by the arrow P, i.e. from the sun gear side, on the one hand to the contact or friction surfaces between the planet gear 8 and the cage 6 as well as the cheek 3 with the thrust washer 12 possible, as well as an improved supply of lubricant in the actual rolling bearing area, which makes it possible to use a bearing pin 4 that is not hollow-drilled, i.e. not integrated into an oiling structure.

Figures 2 - 5 show a first exemplary embodiment of a thrust washer 100, which can be integrated as a thrust washer 12 in the planetary gear 1 from Figure 1. The thrust washer 100 is circular and profiled in a special way. She points out Depressions 102 made on one side of the pane 101, which lead as passages to corresponding flat elevations 103 on the opposite side of the pane 104. In the example shown, four such depressions 102 or elevations 103 are provided, which are distributed equidistantly around the circumference of the thrust washer 100. The depressions 102 extend by a certain angular increment in the circumferential direction and merge back into the undeformed area of the disk via a gentle bend. Seen radially, the depressions 102 only extend a little way to an inner disk section 105, which remains undeformed. In the transition from the respective recess 102 to the disk section 105 there is a relatively sharp, cranked transition zone 106 in which, see the enlarged detailed view according to FIG. 5, the wall thickness is greatly reduced, which makes it possible to form a sharp step, as is clear in FIG shown.

Through this stepped design, two axially offset first and second contact surfaces can be realized, on which, on the one hand, the planetary gear 8 is supported with its end face, and on the other hand, the cage 6.

The first contact surface 107 is formed over the surfaces of the elevations 103. This means that the first contact surface 107 is segmented; it is composed of the four surface segments of the elevations 103. Compared to the inner disk section 102, this first contact surface 107, on which the planetary gear 8 contacts, is axially offset, as Figures 4 and 5 clearly show.

A second contact surface 108 in the shape of a circular ring is formed over the undeformed inner disk section 105, the two contact surfaces 107, 108 being provided on the same side of the disk. It is clearly set back axially relative to the first contact surface 107. The cage 6 is guided on it or runs against it, whereby, as already described in FIG. 1, the cage 6 projects axially beyond the planet gear 8.

In the assembly position, the axial disk 100 rests with the disk surface 101 on the cheek 3, as shown with the axial disk 12 in FIG. The first and second contact surfaces 107, 108 are adjacent to the end face of the planet gear 8 and to Rolling bearings 5 or the cage 6 are arranged. In this arrangement, corresponding guide channels 109 are formed between the elevations 103, resulting from the undeformed sections of the thrust washer 100 located between them. These channels 109 are radially open and run in a quasi V-shape to the central axis of the thrust washer 100. They can be used in the assembly position According to arrow P in Figure 1, the lubricant supplied flows radially into the area of the first and second contact surfaces 107, 108 and into the area of the rolling bearing 5, so a channel structure that is open towards the rolling bearing 5 is formed. The oil consequently wets the contact or friction areas between the individual friction partners as it also supplies the rolling bearing 5. The oil migrates through the bearing and friction area and can also exit radially outwards via this channel structure.

The depressions 102, which are covered axially by the cheek 3, are also open radially outwards. The depressions 102 define corresponding pockets that serve as reservoirs and into which the lubricant can also flow from the radially inside via the arrow P. This virtually ensures a rear lubricant supply, since the lubricant can wet the contact area between the disk side 101 and the cheek 3, where friction can also occur when the axial disk 100 is rotatably mounted on the bearing pin 4.

As a result of the profiling of the thrust washer 100 according to the invention, on the one hand, a corresponding support of the planetary gear 8 and the cage 6 is ensured, the support being provided here in two separate axial planes due to the axial offset of the contact surfaces 107, 108. On the other hand, the structure with the depressions 102 or elevations 103 offers the possibility of the best possible lubricant supply, since a corresponding guide channel structure is formed here, in conjunction with any lubricant reservoirs via the depressions 102, so that on the one hand the actual rolling bearing area is very well supplied with lubricant is, but on the other hand also the corresponding friction or contact areas on the thrust washer 100. This makes it possible to dispense with a lubricant supply to the rolling area via the bearing pin 4, but only The lubricant is supplied via the sun gear side from the radial inside via the thrust washer arrangement.

A second embodiment of a thrust washer 200 according to the invention, which can be used as a thrust washer 12 in the planetary gear 1 according to FIG. 1, is shown in FIGS. 6 - 9. The thrust washer 200 also has several depressions 202 introduced from the disk side 201, in the example shown also four depressions, as well as corresponding flat elevations 203 projecting on the disk side 204. The depressions 202, of which four are also provided here, for example, are again offset equidistantly around the circumference and merge into the neighboring, undeformed pane area via gentle bends. However, similar to the previous exemplary embodiment, they only extend radially to an inner disk section 205, which remains undeformed. This results in a corresponding stepped structure, with a first contact surface 207, which is segmented and is formed over the surfaces of the individual elevations 203, like a second contact surface 208, which is provided via the undeformed disk section 205.

Unlike the embodiment according to FIGS. 2 - 5, no offset transition zone 206 is implemented here. Rather, the transition zone 206 is provided with an opening 209 which is like an elongated hole and extends essentially over the length of the depression 202. The two disk sides 201 and 204 communicate with each other via these openings.

In the assembly position, the thrust washer 200 lies with its disk side 201 against the cheek 3, while the disk side 204 with the two contact surfaces 207, 208 are adjacent to the planet gear 8 and the rolling bearing 5, respectively. Again, the planet gear 8 runs on the first segmented contact surface 207, while the cage 6 runs on the annular contact surface 208.

The profiling also results in a corresponding formation of guide channels 210 between two adjacent elevations 203, as already described for the above embodiment. Here too, the guide channels 210 are essentially V- shaped and open directly onto the cage 6 supported radially on the inside on the contact surface 208. This means that via these guide channels 210 or the guide channel structure in the same way as in the embodiment according to Figures 2 - 5, the lubricant supplied via the arrow P is delivered to the two contact surfaces on the one hand 207, 208 is fed, but on the other hand also directly to the rolling bearing 5.

As described, the recesses 202 of the cheek 3 are arranged opposite each other here, so they are so to speak encroached upon by the cheek 3, so that corresponding pockets are also formed here. However, these are radially open here through the openings 209, so that the lubricant flowing into the recesses 202 can also reach directly into the rolling bearing area through the openings 209. Here, the rolling bearing supply takes place not only via the guide channels 210, but also via the depressions 202 and the openings 209.

Reference character list

Planetary gear planet carrier cheek bearing pin rolling bearing

Cage

Rolling element planetary gear

External teeth Sun gear Thrust washer Thrust washer Thrust washer Disc side Recess Raise Disc side

Disk section Transition zone Contact surface Contact surface Guide channel Thrust disk Disk side Recess Elevation

Disc side disc section

Transition zone contact surface contact surface 09 Breakthrough

210 guide channel

P arrow

Claims

Claims Annular thrust washer for a planetary gear (8) of a planetary gear (1) mounted via a rolling bearing (5), characterized in that on one side of the disk (101, 201) in an outer disk section radially spaced from the inner circumference, there are several offset around the circumference to the outer circumference extended axial recesses (102, 202) and flat elevations (103, 203) corresponding to the recesses (102, 202) are provided on an opposite side of the disk (104, 204), the plurality of flat elevations (103, 203) forming a segmented first Form a contact surface (107, 207), which is adjoined radially on the inside by an annular second contact surface (108, 208) formed via an undeformed inner disk section (105, 205), which is axially set back to the first contact surface (107, 207). Thrust washer according to claim 1, characterized in that each elevation (103, 203) connects with its inner end to the inner disk section (105, 205) via a cranked transition zone (106, 206), the disk thickness in the area of the transition zone (106, 206) is less than the disk thickness in the area of the inner disk section (105). Thrust washer according to claim 2, characterized in that the disk thickness is the same in the area of the elevations (103, 203) and in the area of the inner disk section (105, 205). Thrust washer according to one of the preceding claims, characterized in that each elevation (203) adjoins the inner disk section (205) with its inner end via one or the transition zone (206), with at least one in at least part of the transition zones (206). axial opening (209) is provided. Thrust washer according to claim 4, characterized in that the respective opening (209) is designed as an arcuate elongated hole which is in Circumferential direction extends over at least half the circumferential length of the elevation (203), in particular over the entire circumferential length of the elevation (203).

6. Thrust washer according to one of the preceding claims, characterized in that the elevations (103, 203) are offset equidistantly around the circumference.

7. Planetary gear with a planet carrier (2), on which at least one bearing pin (4) is arranged, a planetary gear (8), which has a roller bearing (5) comprising several rolling elements (7) guided in a cage (6) on the bearing pin (4) is mounted, and at least one thrust washer (12, 100, 200) according to one of the preceding claims.

8. Planetary gear according to claim 7, characterized in that the first contact surface (107, 207) formed via the elevations (103, 203) forms a first contact zone for the planet gear (3), while the annular, axially recessed second contact surface (108, 208) forms a contact zone for the cage (6) which projects axially over the planet gear (8).

9. Planetary gear according to claim 8, characterized in that a lubricant guiding structure is formed via the thrust washer (12, 100, 200), with the lubricant guided from the radial outside to the thrust washer (12, 100, 200) either via between two adjacent elevations (103, 203), which are open radially towards the outer circumference, guide channels (109, 210) are guided to the first and second contact zones (107, 108, 207, 208), or the lubricant is passed over between two adjacent elevations (103 , 203) formed by guide channels (109, 210) which are open radially towards the outer circumference, as well as through the recesses (102, 202) which are provided on the other side of the disk and are open radially towards the outer circumference and the subsequent openings (209) on the first and second Start-up zone (207, 208) is guided.

10. Lubrication device for a planetary gear with a lubricant supply structure, comprising a thrust washer (12, 100, 200) according to one of Claims 1 to 6, wherein the lubricant supplied via the lubricant supply structure either via guide channels (109, 210) formed between two adjacent elevations (103, 203) and open radially towards the outer circumference from the radial outside to the first and second contact zones (107, 108, 207, 208), or wherein the lubricant is guided both via guide channels (210) formed between two adjacent elevations (203) and open radially towards the outer circumference, as well as via the recesses provided on the other side of the disk and open radially towards the outer circumference (202) and the subsequent openings (209) are guided from the radial outside to the first and second contact zones (207, 208).